4.1 One of the factors affecting the performance provided by a cementitious treatment is how readily water vapor passes through it. Hence, the water vapor transmission characteristics of treatments are important in assessing their performance in practical use.4.2 The purpose of this test method is to obtain values of water vapor transfer through treatments that range in permeability from high to low. These values are for use in design, manufacture, and marketing.4.3 Water vapor transmission is not a linear function of film thickness, temperature or relative humidity.4.4 Values of water vapor transmission rate (WVT) and water vapor permeance (WVP) can be used in the relative rating of treatments only if the treatments are tested under the same closely controlled conditions of temperature and relative humidity.1.1 This test method covers the determination of the rate at which water vapor passes through non film forming treatments, such as silanes, siloxanes and blends of silanes/siloxanes applied to cementitious substrates.1.2 This test method covers the use of the wet cup technique, which most closely approaches the exterior conditions for use for these materials. Other conditions can be used if agreed upon between purchaser and supplier. Agreement should not be expected between results obtained by different methods or test conditions.1.3 The values stated in SI units of measurement are designated as the standard. Factors for conversion to inch-pound units are given in 9.2.1.1 and 9.2.2.1.1.4 This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility of the user of this standard to establish appropriate safety, health, and environmental practices and determine the applicability of regulatory limitations prior to use.1.5 This international standard was developed in accordance with internationally recognized principles on standardization established in the Decision on Principles for the Development of International Standards, Guides and Recommendations issued by the World Trade Organization Technical Barriers to Trade (TBT) Committee.

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Limiting the concentration of deposit-forming impurities in steam is of significance to protect both steam generators and steam turbines from damage or degradation of performance, or both. Steam entering superheaters and reheaters of steam generators always contains some impurities. If the concentration of impurities is sufficiently low, the impurities are dissolved in superheated steam and are carried out of the steam generator. However, if the steam contains a sufficient amount of any substance to exceed its solubility limit in steam, the substance is likely to form a deposit on the heat-transfer surface. Because heat transfer in superheaters and reheaters in fossil-fueled steam generators is controlled principally by the low heat-transfer coefficient on the gas side, the formation of steam-side deposits will have little effect on the overall heat-transfer rate. However, steam-side deposits will increase the operating temperature of the heat-transfer surface. Such temperature increases can lead to swelling and ultimately to rupture of the tubing. Also, aggressive materials can concentrate under solid deposits of porous materials, such as magnetite (Fe3O4), and can cause serious corrosion of the tubing. As steam flows through turbines, its temperature and pressure decrease rapidly. Because the ability of steam to dissolve impurities decreases with decreasing temperature and pressure, impurities in steam may exceed their solubility limit and form deposits on the turbine. Such deposits reduce steam flow area, particularly in the high-pressure portion of the turbine where flow passages are small, and the roughness of deposits and their effect on blade contours result in losses of turbine efficiency. All of these effects lead to reduction of the plant maximum capacity, which appreciably reduces the financial return on the capital investment in the power plant. Furthermore, aggressive materials, such as sodium hydroxide (NaOH) and sodium chloride (NaCl), may condense and deposit on turbine surfaces. Such deposits occasionally contribute to failure due to cracking of highly stressed turbine blades and rotors. Repairs and outages are extremely costly. By monitoring the concentration of deposit-forming impurities in steam, a power plant operator can take steps necessary to limit the impurities to tolerable concentrations and thus minimize or eliminate losses due to excessive deposits.1.1 These test methods cover the determination of the amount of deposit-forming impurities in steam. Determinations are made on condensed steam samples in all test methods. Test Methods A, B, and C give a measure of the amount of total deposit-forming material present; Test Method D deals with special constituents that may be present. Special precautions and equipment, calculation procedures, and ranges of applicability are described. The following test methods are included: Sections Test Method A (Gravimetric or Evaporative) 6 to 12 Test Method B (Electrical Conductivity)13 to 19 Test Method C (Sodium Tracer)20 to 26 Test Method D (Silica and Metals)27 to 30 1.2 Test Method A is applicable for determining total dissolved and suspended solids in concentrations normally not less than 0.4 mg/L (ppm). It is applicable only to long-time steady-state conditions and is not applicable for transients. 1.3 Test Method B will measure minimum impurity concentrations varying from 3 mg/L (ppm) down to at least 0.005 mg/L (ppm), depending on the means for removing dissolved gases from the steam condensate. The means for removing dissolved gases also affects the storage capacity of steam condensate in the system and, thus, affects the response of the system to transients. 1.4 Because of the high sensitivity of methods for measuring sodium in steam condensate, Test Method C provides the most sensitive measure of impurity content for samples in which sodium is an appreciable percentage of the impurities present. Concentrations as low as 4.0 μg/L (ppb) can be detected by inductively coupled plasma atomic emission spectroscopy, 0.2 μg/L (ppb) by atomic absorption spectrophotometry, 0.1 μg/L (ppb) by graphite furnace atomic absorption spectroscopy, and as low as 0.5 μg/L (ppb) by sodium ion electrode. The apparatus can be designed with low volume, and, therefore, Test Method C is the most responsive to transient conditions. 1.5 Test Method D covers the determination of silica and metals in steam, which are not included in Test Methods B and C and are not individually determined using Test Method A. 1.6 This standard does not purport to address the safety concerns, if any, associated with its use. It is the responsibility of the user of this standard to establish appropriate safety and health practices and determine the applicability of regulatory limitations prior to use. 6.1 The gravimetric test method is recommended for applications for which an average value of impurities over a period of several days or weeks is desired. It is particularly useful for samples in which a large percentage of the impurities are insoluble, do not contain sodium, or do not contribute appreciably to the electrical conductivity of the samples, because the other methods are not satisfactory for these conditions. Examples of such impurities are metals and metal oxides. It is not applicable when short-time trends are of interest or when immediate results are desired. The test method is useful for the determination of concentrations of impurities of 0.25 mg/L (ppm) or greater when a previously collected sample is used and for impurities concentrations of 0.1 mg/L (ppm) or greater when continuous sampling is used. Concentrations less than 0.1 mg/L (ppm) can be determined if a continuously flowing sample is evaporated for an extremely long period of time. 13.1 Ion-Exchange Degasser—An ion-exchange degasser consists of an ion-exchange resin that exchanges hydrogen ions for all cations in the sample, thereby eliminating all basic dissolved gases, including volatile amines. By converting mineral salts to their acid forms, it also increases the specific conductance of the impurities. As a result, the linear relationship between conductivity and impurity content is extended to a much lower level, depending on the carbon dioxide content. The test method is very useful for measuring low concentrations of impurities, such as condenser cooling water leakage, in steam condensate, and it is especially useful, for indicating small or intermittent changes in impurity content from some normal value. The test method is not satisfactory for the determination of impurities in steam condensate samples that contain acidic gases, such as carbon dioxide, large percentages of insoluble matter, or substances that ionize weakly. The sensitivity and accuracy of the method are decreased for samples in which hydroxides represent an appreciable percentage of the impurities, because hydroxides, which contribute to the formation of deposits, are converted to water by the ion-exchange resin. This characteristic is particularly significant when steam is generated at sufficiently high pressure to cause appreciable vaporization of sodium hydroxide from the boiler water. 13.2 Mechanical and Ion-Exchange Degasser—By combining mechanical and ion-exchange degassing of steam or condensed steam, or both, effective elimination of both acidic and basic dissolved gases is attained. This arrangement has the same advantages and limitations as the ion-exchange degasser alone, except that it will remove acidic gases, and the greater sensitivity afforded by measuring the conductance at atmospheric boiling water temperature extends the linear relationship between conductivity and the ionized impurity content down to about at least 0.005 mg/L (ppm). Although the relationship becomes somewhat nonlinear, the conductance is sensitive to concentration changes down to at least 0.005 mg/L (ppm). 20.1 The principal advantages of the sodium tracer test method are the freedom from interferences, the ability to measure extremely small concentrations of impurities, and the rapid response to transient conditions because of the absence of large stagnant sample volumes, such as reboil chambers. Either of two procedures may be employed for the sodium determination, as follows: Precise control of sample temperature is not required for the flame photometry test method. If the impurities are principally sodium compounds, impurity concentrations as low as 0.6 μg/L (ppb) may be detected by the flame photometry method and as low as 0.5 μg/L (ppb) by the sodium ion electrode test method. The sodium tracer test method is not recommended for samples having large percentages of impurities that do not contain sodium. 27.1 Silica and various metals are impurities that are occasionally found in steam and have definite tendencies to form deposits. Since these substances are not isolated when using Test Method A and are not detected when using Test Methods B and C, it is advisable to determine their concentrations separately when they are present in significant quantities.

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This specification covers liquid membrane-forming compounds suitable for application to concrete surfaces to reduce the loss of water during the early-hardening period. White-pigmented membrane-forming compounds serve the additional purpose of reducing the temperature rise in concrete exposed to radiation from the sun. The membrane-forming compounds covered by this specification are suitable for use as curing media for fresh concrete, and may also be used for further curing of concrete after removal of forms or after initial moist curing. Liquid membrane-forming compound types 1 and 1-D shall be clear or translucent. Type 2 liquid membrane-forming compounds shall consist of finely-divided white pigment and vehicle, ready-mixed for immediate use as is. Liquid membrane-forming compounds, when tested, shall restrict the loss of water not more than the requirements prescribed. Type 2 liquid membrane-forming compounds, when tested, shall exhibit a daylight reflectance of not less than 60 %. Liquid membrane-forming compounds, when tested, shall dry to touch in not more than 4 h.1.1 This specification covers liquid membrane-forming compounds suitable for application to concrete surfaces to reduce the loss of water during the early-hardening period. White-pigmented membrane-forming compounds serve the additional purpose of reducing the temperature rise in concrete exposed to radiation from the sun. The membrane-forming compounds covered by this specification are suitable for use as curing media for fresh concrete, and may also be used for further curing of concrete after removal of forms or after initial moist curing.NOTE 1: This specification addresses only those properties listed in Sections 6 through 9. Membrane-forming compounds with special properties including better water retention, minimum solids content, resistance to ultraviolet radiation, acid and alkali resistance and non-interference with adhesives are described in Specification C1315.NOTE 2: Solutions of silicate salts are chemically reactive in concrete rather than membrane-forming; therefore, they do not meet the intent of this specification.1.2 This is a performance specification. The allowable composition of products covered by this specification is limited by various local, regional, and national regulations. Issues related to air quality (solvent emission), worker exposure, and other hazards are not addressed here. It is the responsibility of the producers and users of these materials to comply with pertinent regulations.1.3 Warning—Some VOC exempt solvents used to meet the regulations are extremely flammable with low auto ignition temperatures and rapid evaporation rates. Consult the manufacturer's product information sheet for important application and safety information.1.4 The text of this standard references notes and footnotes which provide explanatory material. These notes and footnotes shall not be considered as requirements of the standard.1.5 The values stated in SI units are to be regarded as the standard. The values given in parentheses are provided for informational purposes only.1.6 The following precautionary caveat pertains only to the test methods portion, Section 11, of this specification: This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility of the user of this standard to establish appropriate safety, health, and environmental practices and determine the applicability of regulatory limitations prior to use.1.7 This international standard was developed in accordance with internationally recognized principles on standardization established in the Decision on Principles for the Development of International Standards, Guides and Recommendations issued by the World Trade Organization Technical Barriers to Trade (TBT) Committee.

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4.1 The Manual Observer-Dependent Assay—The manual quantification of cell and CFU cultures based on observer-dependent criteria or judgment is an extremely tedious and time-consuming task and is significantly impacted by user bias. In order to maintain consistency in data acquisition, pharmacological and drug discovery and development studies utilizing cell- and colony-based assays often require that a single observer count cells and colonies in hundreds, and potentially thousands of cultures. Due to observer fatigue, both accuracy and reproducibility of quantification suffer severely (5). When multiple observers are employed, observer fatigue is reduced, but the accuracy and reproducibility of cell and colony enumeration is still significantly compromised due to observer bias and significant intra- and inter-observer variability (2, 4) . Use of quantitative automated image analysis provides data for both the number of colonies as well as the number of cells in each colony. These data can also be used to calculate mean cells per colony. Traditional methods for quantification of colonies by hand-counting coupled with an assay for cell number (for example, DNA or mitochondrial) remains a viable method that can be used to calculate the mean number of cells per colony. These traditional methods have the advantage that they are currently less labor intensive and less technically demanding (8, 9). However, the traditional assays do not, provide colony level information (for example, variation and skew), nor do they provide a means for excluding cells that are not part of a colony from the calculation of mean colony size. As a result, the measurement of the mean number of cells per colony that is obtained from these alternative methods may differ when substantial numbers of cells in a sample are not associated with colony formation. By employing state-of-the-art image acquisition, processing and analysis hardware and software, an accurate, precise, robust and automated analysis system is realized.4.1.1 Areas of Application—Cell and colony enumeration (CFU assay) is becoming particularly important in the manufacture, quality assurance/control (QA/QC), and development of product safety and potency release criteria for cell-based regenerative medicine and cellular therapy. The U.S. Food and Drug Administration (FDA) has a guidance document that indicates that the CFU assay may be appropriate for testing stability of placental and umbilical cord blood-derived stem cells (7). Since cell source validation and QA/QC comprise approximately 50 % of the manufacturing cost of cellular therapies (10), developing a precise, robust, and cost-effective means for enumerating cells and colonies is vital to sustainability and growth in this industry. The broad areas of use for automated analysis of colony forming unit assays include:4.1.1.1 Characterization of a cell source by correlating biological potential and functional potency with CFU formation.4.1.1.2 Characterization of the effect of processing steps or biological or physical manipulation (for example, stimuli) on cells or colony formation.4.1.1.3 Cell and colony characterization using specific fluorescent and non-fluorescent (differentiation) markers.4.1.1.4 Extrapolation of the biological potency (for example, differentiation, proliferative, and so forth) of a larger sample from application of colony forming assay to sub-samples.4.1.1.5 Provision of criteria for sub-colony selection of preferred colonies (specific tissue type, proliferation rate, and so forth) for use and/or further expansion.4.2 The Technology (image acquisition, processing, and analysis)—Current standards utilize user input for defining the presence and location of colonies based on visualization of an entire culture surface at low magnification through the eyepieces of a microscope. In this case, the sample may be viewed in transmission light mode (unstained or with a histochemical marker) or fluorescently with a dye or antibody. For this practice, the colony count is the only measurable output parameter. Utilizing a microscope-based imaging system to stitch together high resolution image tiles into a single mosaic image of the entire culture surface and subsequently “clustering” segmented cells using image processing algorithms to delineate colonies, provides a fully automated, accurate, and precise method for characterizing the biological potential and functional potency of the cultured cells. Furthermore, extracted parameters in addition to colony number provide means of further characterization and sub-classification of colony level statistics. These parameters include, but are not limited to, cell/nuclear count, cell/nuclear density, colony morphology (shape and size parameters), secondary marker coverage, effective proliferation rates, and so forth (Fig. A1.2). In addition to human connective tissue progenitors (CTPs) derived from bone, bone marrow, cartilage, adipose tissue, muscle, periosteum, and synovium, this practice and technology has been implemented in the cell and colony identification and characterization of several cell and tissue types including: umbilical cord blood hematopoietic stem cells (Fig. X1.2); adipose-derived stem cells (Fig. X1.3); and human epidermal (Fig. X1.4) and dermal (Fig. X1.5) stem cells.4.3 Benefits of Automated Analysis of CFU Assays—Automated analysis is expected to provide more rapid, reproducible, and precise results in comparison to the manual enumeration of cells and colonies utilizing a microscope and hemocytometer. In addition to being time consuming, labor intensive, and subjective, manual enumeration has been shown to have a significant degree of intra- and inter-observer variability, with coefficients of variation (CV) ranging from 8.1 % to 40.0 % and 22.7 % to 80 %, respectively. Standard CVs for cell viability assessment and progenitor (colony) type enumeration have been shown to range from 19.4 % to 42.9 % and 46.6 % to 100 %, respectively (4, 11, 12). In contrast, studies focusing on bacteria, bone marrow-derived stem cells and osteogenic progenitor cells have collectively concluded that automated enumeration provides significantly greater accuracy, precision, and/or speed for counting and sizing cells and colonies, relative to conventional manual methodologies (4-6). Automated methods for enumerating cells and colonies are less biased, less time consuming, less laborious, and provide greater qualitative and quantitative data for intrinsic characteristics of cell and colony type and morphology.4.4 Selection of Cell Culture Surface Area and Optimal Cell Seeding Density—When performing a CFU assay, optimizing the cell culture surface area and cell seeding density is critical to developing methods for generating reliable and reproducible colony- and cell-level data. If seeding density is too low, then the frequency of observed colonies is decreased. This can result in a sampling size that is inadequate to characterize the population of CFUs in the sample. If seeding density is too high, the colonies that are formed may be too closely spaced. Overlapping colony footprints compromise colony counting and characterization. Because the intrinsic range of CFU prevalence in a given cell source may vary widely, in many cases, a trial and error approach to optimizing cell seeding density (or range of densities) that are needed for a given cell source will be necessary. It is important to note that the more heterogeneous the cell source (for example, bone marrow), the more colonies that are needed to accurately represent the stem and progenitor cell constituents. Further, the cell type, effective proliferation rate (EPR) and specific cell culture conditions (for example, media, serum, factors, oxygen tension, and so forth) can impact colony formation. For example, the automated CFU assay depicted in Fig. A1.2 employs a six-day culture period, two media changes, 20 % oxygen tension, alpha-MEM media (with 25 % fetal bovine serum, ascorbate, dexamethasone and streptomycin), an optimized cell seeding density of 250 000 nucleated cells per cm2 (250 000 cells per 1 mL of cell culture medium) and a cell culture surface area of 22 mm by 22 mm (dual-chamber Lab-Tek culture slides) (12, 13).4.5 Useful Documents—A number of useful documents are available that address best practices for conducting quantitative measurements of cells using imaging approaches: Guide F2998, Guide F3294, ISO 20391-1, ISO 20391-2, and “FDA Guidance on Technical Performance Assessment of Digital Pathology Whole Slide Imaging Devices,” (14).1.1 This practice, provided its limitations are understood, describes a procedure for quantitative measurement of the number and biological characteristics of colonies derived from a stem cell or progenitor population using image analysis.1.2 This practice is applied in an in vitro laboratory setting.1.3 This practice utilizes: (a) standardized protocols for image capture of cells and colonies derived from in vitro processing of a defined population of starting cells in a defined field of view (FOV), and (b) standardized protocols for image processing and analysis.1.4 The relevant FOV may be two-dimensional or three-dimensional, depending on the CFU assay system being interrogated.1.5 The primary unit to be used in the outcome of analysis is the number of colonies present in the FOV. In addition, the characteristics and sub-classification of individual colonies and cells within the FOV may also be evaluated, based on extant morphological features, distributional properties, or properties elicited using secondary markers (for example, staining or labeling methods).1.6 Imaging methods require that images of the relevant FOV be captured at sufficient resolution to enable detection and characterization of individual cells and over a FOV that is sufficient to detect, discriminate between, and characterize colonies as complete objects for assessment.1.7 Image processing procedures applicable to two- and three-dimensional data sets are used to identify cells or colonies as discreet objects within the FOV. Imaging methods may be optimized for multiple cell types and cell features using analytical tools for segmentation and clustering to define groups of cells related to each other by proximity or morphology in a manner that is indicative of a shared lineage relationship (that is, clonal expansion of a single founding stem cell or progenitor).1.8 The characteristics of individual colony objects (cells per colony, cell density, cell size, cell distribution, cell heterogeneity, cell genotype or phenotype, and the pattern, distribution and intensity of expression of secondary markers) are informative of differences in underlying biological properties of the clonal progeny.1.9 Under appropriately controlled experimental conditions, differences between colonies can be informative of the biological properties and underlying heterogeneity of colony founding cells (CFUs) within a starting population.1.10 Cell and colony area/volume, number, and so forth may be expressed as a function of cell culture area (square millimeters), or initial cell suspension volume (milliliters).1.11 Sequential imaging of the FOV using two or more optical methods may be valuable in accumulating quantitative information regarding individual cells or colony objects in the sample. In addition, repeated imaging of the same sample will be necessary in the setting of process tracking and validation. Therefore, this practice requires a means of reproducible identification of the location of cells and colonies (centroids) within the FOV area/volume using a defined coordinate system.1.12 To achieve a sufficiently large field-of-view (FOV), images of sufficient resolution may be captured as multiple image fields/tiles at high magnification and then combined together to form a mosaic representing the entire cell culture area.1.13 Cells and tissues commonly used in tissue engineering, regenerative medicine, and cellular therapy are routinely assayed and analyzed to define the number, prevalence, biological features, and biological potential of the original stem cell and progenitor population(s).1.13.1 Common applicable cell types and cell sources include, but are not limited to: mammalian stem and progenitor cells; adult-derived cells (for example, blood, bone marrow, skin, fat, muscle, mucosa) cells, fetal-derived cells (for example, cord blood, placental/cord, amniotic fluid); embryonic stem cells (ESC) (that is, derived from inner cell mass of blastocysts); induced pluripotent cells (iPC) (for example, reprogrammed adult cells); culture expanded cells; and terminally differentiated cells of a specific type of tissue.1.13.2 Common applicable examples of mature differentiated phenotypes which are relevant to detection of differentiation within and among clonal colonies include: hematopoietic phenotypes (erythrocytes, lymphocytes, neutrophiles, eosinophiles, basophiles, monocytes, macrophages, and so forth), adult tissue-specific progenitor cell phenotypes (oteoblasts, chondrocytes, adipocytes, and so forth), and other tissues (hepatocytes, neurons, endothelial cells, keratinocyte, pancreatic islets, and so forth).1.14 The number of stem cells and progenitor cells in various tissues can be assayed in vitro by liberating the cells from the tissues using methods that preserve the viability and biological potential of the underlying stem cell and/or progenitor population, and placing the tissue-derived cells in an in vitro environment that results in efficient activation and proliferation of stem and progenitor cells as clonal colonies. The true number of stem cells and progenitors (true colony forming units (tCFU)) can thereby be estimated on the basis of the number of colony-forming units observed (observed colony forming units (oCFU)) to have formed (1-3)2 (Fig. A1.1). The prevalence of stem cells and/or progenitors can be estimated on the basis of the number of observed colony-forming units (oCFU) detected, divided by the number of total cells assayed.1.15 The automated image acquisition and analysis approach (described herein) to cell and colony enumeration has been validated and found to provide superior accuracy and precision when compared to the current “gold standard” of manual observer defined visual cell and colony counting under a brightfield or fluorescent microscope with or without a hemocytometer (4), reducing both intra- and inter-observer variation. Several groups have attempted to automate this and/or similar processes in the past (5, 6) . Recent reports further demonstrate the capability of extracting qualitative and quantitative data for colonies of various cell types at the cellular and even nuclear level (4, 7).1.16 Advances in software and hardware now broadly enable systematic automated analytical approaches. This evolving technology creates the need for general agreement on units of measurement, nomenclature, process definitions, and analytical interpretation as presented in this practice.1.17 Standardized methods for automated CFU analysis open opportunities to enhance the value and utility of CFU assays in several scientific and commercial domains:1.17.1 Standardized methods for automated CFU analysis open opportunities to advance the specificity of CFU analysis methods though optimization of generalizable protocols and quantitative metrics for specific cell types and CFU assay systems which can be applied uniformly between disparate laboratories.1.17.2 Standardized methods for automated CFU analysis open opportunities to reduce the cost of colony analysis in all aspects of biological sciences by increasing throughput and reducing work flow demands.1.17.3 Standardized methods for automated CFU analysis open opportunities to improve the sensitivity and specificity of experimental systems seeking to detect the effects of in vitro conditions, biological stimuli, biomaterials and in vitro processing steps on the attachment, migration, proliferation, differentiation, and survival of stem cells and progenitors.1.18 Limitations are described as follows:1.18.1 Colony Identification—Cell Source/Colony Type/Marker Variability—Stem cells and progenitors from various tissue sources and in different in vitro environments will manifest different biological features. Therefore, the specific means to detect cells or nuclei and secondary markers utilized and the implementation of their respective staining protocols will differ depending on the CFU assay system, cell type(s) and markers being interrogated. Optimized protocols for image capture and image analysis to detect cells and colonies, to define colony objects and to characterize colony objects will vary depending on the cell source being utilized and CFU system being used. These protocols will require independent optimization, characterization and validation in each application. However, once defined, these can be generalized between labs and across clinical and research domains.1.18.2 Instrumentation-Induced Variability in Image Capture—Choice of image acquisition components described above may adversely affect segmentation of cells and subsequent colony identification if not properly addressed. For example, use of a mercury bulb rather than a fiber-optic fluorescent light source or the general misalignment of optics could produce uneven illumination or vignetting of tiled images comprising the primary large FOV image. This may be corrected by applying background subtraction routines to each tile in a large FOV image prior to tile stitching.1.18.3 CFU Assay System Associated Variation in Imaging Artifacts—In addition to the presentation of colony objects with unique features that must be utilized to define colony identification, each image from each CFU system may present non-cell and non-colony artifacts (for example, cell debris, lint, glass aberrations, reflections, autofluorescence, and so forth) that may confound the detection of cells and colonies if not identified and managed.1.18.4 Image Capture Methods and Quality Control Variation—Variation in image quality will significantly affect the precision and reproducibility of image analysis methods. Variation in focus, illumination, tile registration, exposure time, quenching, and emission spectral bleeding, are all important potential limitations or threats to image quality and reproducibility.1.19 The values stated in SI units are to be regarded as standard. No other units of measurement are included in this standard.1.20 This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility of the user of this standard to establish appropriate safety and health practices and determine the applicability of regulatory limitations prior to use.1.21 This international standard was developed in accordance with internationally recognized principles on standardization established in the Decision on Principles for the Development of International Standards, Guides and Recommendations issued by the World Trade Organization Technical Barriers to Trade (TBT) Committee.

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5.1 When a superplastic material is regularly being used in industrial production, it is often convenient to use the bulge test to qualify a batch or heat lot to an acceptance criterion. Comparing these test methods with Test Method E2448, the bulge test does not require a machined test specimen, it is more convenient to perform, and it most closely simulates the multiaxial stresses and strains present in forming parts. These test methods do not measure the intrinsic superplastic properties of a material. Test Method E2448 should be used in that instance.1.1 These test methods describe procedures for determining the biaxial formability of a test specimen of superplastic metallic sheet in a circular die.1.2 The intent of these test methods are primarily to be used as tests of superplasticity as measured by the ability to form to a prescribed depth in a die cavity without rupturing. These test methods can also be used to generate material for the measurement of cavitation in the formed part. These can be used as go/no go criteria for qualification to a specification.1.3 These test methods have been used successfully with aluminum alloys. The use of these test methods on other metals should be verified.1.4 The values stated in SI units are to be regarded as standard. No other units of measurement are included in this standard.1.5 This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility of the user of this standard to establish appropriate safety, health, and environmental practices and determine the applicability of regulatory limitations prior to use.1.6 This international standard was developed in accordance with internationally recognized principles on standardization established in the Decision on Principles for the Development of International Standards, Guides and Recommendations issued by the World Trade Organization Technical Barriers to Trade (TBT) Committee.

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4.1 Moisture permeating from concrete substrates can detrimentally affect the performance of resilient floor covering systems. All resilient flooring and adhesive manufacturers have a maximum acceptable level of moisture in which their products can perform satisfactorily. If pre-installation moisture tests indicate that the moisture level is unacceptable for the specified floor covering to be installed, one option is to apply a topical treatment to the concrete substrate surface to mitigate the moisture condition. Experience has shown that certain types of membrane-forming moisture mitigation systems have more desirable properties and successful performance than others. Requirements for membrane-forming moisture mitigation systems to be used, and other related details, are generally included as part of the project plans, or specification details, and may vary from the minimum recommendations set forth in this practice.4.2 This practice is intended for use after it has been determined that a floor moisture condition exceeds the resilient floor covering or adhesive manufacturer’s requirements, or both, as tested according to Test Methods F1869, F2170, and F2420.4.3 Membrane-forming moisture mitigation systems are not intended for use over gypsum-based substrates or other moisture sensitive substrates.1.1 This practice covers the properties, application, and performance of a two-component resin based membrane-forming moisture mitigation system to high moisture concrete substrates prior to the installation of resilient flooring.1.2 This practice includes recommendations for the preparation of the concrete surface to receive a two-component resin based membrane-forming moisture mitigation system.1.3 This practice does not supersede written instructions of the two-component resin based membrane-forming moisture mitigation system manufacturer, the resilient flooring manufacturer, underlayment manufacturer, the adhesive manufacturer, or other components of the finish flooring system, or combinations thereof. Users of this practice shall review manufacturer’s technical data sheets and installation instructions for compatibility of system components.1.4 The following membrane-forming or non membrane-forming moisture mitigation systems are not included in the scope of this practice:1.4.1 Moisture mitigation systems that chemically react with any constituent of the concrete to form a gel or crystalline substance within the concrete.1.4.2 Penetrating, water- or solvent-based compounds that do not form a continuous membrane on the concrete surface.1.4.3 Water-based membrane-forming moisture mitigation systems are not included in the scope of this document.1.5 The values stated in inch-pound units are to be regarded as standard. The values given in parentheses are mathematical conversions to SI units that are provided for information only and are not considered standard.1.6 This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility of the user of this standard to establish appropriate safety, health, and environmental practices and determine the applicability of regulatory limitations prior to use.1.7 This international standard was developed in accordance with internationally recognized principles on standardization established in the Decision on Principles for the Development of International Standards, Guides and Recommendations issued by the World Trade Organization Technical Barriers to Trade (TBT) Committee.

定价： 515元 / 折扣价： 438 元 加购物车

This specification deals with molds for forming concrete test cylinders vertically. Molds shall be constructed in the form of right circular cylinders and have a nominal inside height equal to twice the nominal inside diameter. The following are types of molds covered: reusable molds and single-use molds. Reusable molds shall be made of nonabsorptive materials and shall be tested for water leakage. Single-use molds may be made of sheet metal, plastic, suitably treated paper products, or other materials. These materials shall conform to the following requirements: water leakage, absorptivity, and elongation. The following are additional requirements for the types of single-use molds: plastic mold—wall thickness, bottom design, and material; paper molds—side walls, bottom caps, and waterproofing; and sheet metal molds—metal thickness, bottom design, top edge, and coating. Test for elongation, absorption, and water leakage shall also be performed.1.1 This specification covers molds for use in forming cylindrical concrete specimens. The provisions of this specification include the requirements for both reusable and single-use molds.NOTE 1: Sizes included are molds having diameters from 50 mm [2 in.] to 900 mm [36 in.].1.2 The text of this standard refers to notes and footnotes that which provide explanatory material. These notes and footnotes (excluding those in tables and figures) shall not be considered as requirements of the standard.1.3 The values stated in either SI units or inch-pound units are to be regarded separately as standard. The values stated in each system are not necessarily exact equivalents; therefore, to ensure conformance with the standard, each system shall be used independently of the other, and the values from the two systems shall not be combined.1.4 The following safety hazards caveat pertains only to the test method described in this specification: This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility of the user of this standard to establish appropriate safety and health practices and determine the applicability of regulatory limitations prior to use.1.5 This international standard was developed in accordance with internationally recognized principles on standardization established in the Decision on Principles for the Development of International Standards, Guides and Recommendations issued by the World Trade Organization Technical Barriers to Trade (TBT) Committee.

定价： 590元 / 折扣价： 502 元 加购物车

4.1 The moisture retaining ability of a product as determined by this test method is used to assess the suitability of materials for contributing to an appropriate curing environment for concrete. The laboratory test method is used both in formulating and in specifying or qualifying curing products. This test method gives the user a measure of the ability of tested curing materials to impede the escape of water from a hydraulic cement mortar. Since it is desirable to retain water in fresh concrete to promote the hydration process, failure of the product to minimize the escape of water may lead to loss of strength, cracking, shrinkage, or low abrasion resistance of the hardened concrete, or a combination thereof.4.2 Many factors affect the laboratory test results. Test results obtained may be highly variable as indicated by the precision statement. Critical factors include the precision of the control of the temperature, humidity and air circulation in the curing cabinet, preparation and sealing of the mortar specimens, the age and surface condition of the mortar specimen when the curing product is applied, and the uniformity and quantity of application of the curing membrane.1.1 This test method covers laboratory determination of the ability of liquid membrane-forming compounds for curing concrete to reduce moisture loss from mortar specimens during the early hardening period as a measure of their applicability for curing concrete.1.2 The values stated in SI units are to be regarded as standard. No other units of measurement are included in this standard.1.3 This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility of the user of this standard to establish appropriate safety, health, and environmental practices and determine the applicability of regulatory limitations prior to use. (Warning—Fresh hydraulic cementitious mixtures are caustic and may cause chemical burns to skin and tissue upon prolonged exposure.)21.4 This international standard was developed in accordance with internationally recognized principles on standardization established in the Decision on Principles for the Development of International Standards, Guides and Recommendations issued by the World Trade Organization Technical Barriers to Trade (TBT) Committee.

定价： 590元 / 折扣价： 502 元 加购物车

This specification covers the standard requirements for commercial zinc casting alloys in ingot form for use in the manufacture of sheet metal forming dies, sand cast or plaster cast forming dies, and plastic injection molds. Kirksite A alloy (UNS Z35543) is intended for use in the fabrication of dies for sheet metal stamping under drop hammer and hydraulic pressure while Kirksite B alloy (UNS Z35542) is a special purpose alloy of closely controlled composition and is primarily used in the manufacture of plastic injection molds. The alloys may be made by any approved process and shall be of uniform quality and free from dross, slag, or other harmful contamination. Jumbo or block ingots shall conform to the configuration, or to a shape and size previously agreed upon. Conformance with the composition requirements for aluminum, cadmium, copper, iron, lead, magnesium, tin and zinc shall be determined by spectrographic or chemical analysis. The samples for chemical analysis shall be taken from the material by drilling, sawing, milling, turning, or clipping a representative piece or pieces of the ingot.1.1 This specification covers commercial zinc alloys in ingot form for remelting for the manufacture of dies and molds from the alloys as shown in Table 1.1.2 This specification presents requirements for zinc alloys suitable for the production of sand cast or plaster cast forming dies for sheet metal stamping operations and plastic injection molding. Alloy A is intended for use in the fabrication of dies for sheet metal stamping under drop hammer and hydraulic pressure. Alloy B is a special purpose alloy of closely controlled composition and is primarily used in the manufacture of plastic injection molds.1.3 This specification covers two zinc alloys which are specified and designated as follows:UNS ASTM TraditionalZ35543 Alloy A Kirksite AZ35542 Alloy B Kirksite B1.4 The values stated in inch-pound units are to be regarded as standard. The values given in parentheses are mathematical conversions to SI units that are provided for information only and are not considered standard.1.5 This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility of the user of this standard to become familiar with all hazards including those identified in the appropriate Safety Data Sheet (SDS) for this product/material as provided by the manufacturer, to establish appropriate safety, health, and environmental practices, and determine the applicability of regulatory limitations prior to use.1.6 This international standard was developed in accordance with internationally recognized principles on standardization established in the Decision on Principles for the Development of International Standards, Guides and Recommendations issued by the World Trade Organization Technical Barriers to Trade (TBT) Committee.

定价： 515元 / 折扣价： 438 元 加购物车

This specification covers the performance requirements for membrane-forming liquids suitable for use as curing compounds and sealers for fresh and hardened concrete. Each membrane should have good alkali resistance, acid resistance, adhesion-promoting qualities, and resistance to degradation by UV light. The materials are limited to clear or translucent and white pigmented materials, all of which are classified into non-yellowing, moderately yellowing, or yellows or darkens unrestrictedly.1.1 This specification provides requirements for membrane-forming liquids suitable for use as curing compounds and sealers on freshly placed concrete and as sealers on hardened concrete. These membranes have special properties, such as, alkali resistance, acid resistance, adhesion-promoting qualities, and resistance to degradation by UV light.NOTE 1: For liquid membrane-forming curing compounds specified primarily by their ability to retain water in newly placed concrete (and by drying time, and for white pigmented products, reflectance), see Specification C309.1.2 This is a performance specification. The allowable composition of products covered by this specification is limited by various local, regional, and national regulations. Issues related to air quality (solvent emission), worker exposure, and other hazards are not addressed here. It is the responsibility of the producers and users of these materials to comply with pertinent regulations.Warning—Some VOC exempt solvents used to meet the regulations are extremely flammable with low auto ignition temperatures and rapid evaporation rates. Consult the manufacturer's product information sheet for important application and safety information.1.3 The values stated in SI units are to be regarded as the standard. (Inch pound units are shown in parentheses).1.4 The following precautionary caveat pertains only to the test methods portion, Section 9, of this specification. This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility of the user of this standard to establish appropriate safety, health, and environmental practices and determine the applicability of regulatory limitations prior to use.1.5 This international standard was developed in accordance with internationally recognized principles on standardization established in the Decision on Principles for the Development of International Standards, Guides and Recommendations issued by the World Trade Organization Technical Barriers to Trade (TBT) Committee.

定价： 590元 / 折扣价： 502 元 加购物车

5.1 The forming limit curve (FLC) is specific to the material sampled. It can change if the material is subjected to cold work or any annealing process. Thus, two samples from a given lot of material can produce different curves if their processing is varied.5.2 The processing history of the material must be known if the test is to be considered representative of a grade of a product.5.3 A forming limit curve (FLC) defines the maximum (limiting) strain that a given sample of a sheet metal can undergo for a range of forming conditions, such as deep drawing, plane strain, biaxial stretching, and bending over a radius in a press and die drawing operation, without developing a localized zone of thinning (localized necking) that would indicate incipient failure.5.3.1 FLCs may be obtained empirically by using a laboratory hemispherical punch biaxial stretch test and also a tension test to strain metal sheet test specimens, from a material sample, from beyond their elastic limit to just prior to localized necking and fracture.5.3.1.1 Since the location of localized necking and fracture cannot be predetermined, one or both surfaces of test specimens are covered with a pattern of gauge length measurement units, usually as squares or small diameter circles, by a suitable method such as scribing, photo-grid, or electro-etching, and then each test specimen is formed to the point of localized necking, or fracture.5.3.2 Strains in the major (e1) and minor (e2) directions are measured using individual gauge length measurement units on the pattern in the area of the localized necking or fracture.5.3.2.1 Test specimens of varied widths are used to produce a wide range of strain states in the minor (e2) direction.5.3.2.2 The major strain (e1) is determined by the capacity of the material to be stretched in one direction as simultaneous surface forces either stretch, do not change, or compress, the metal in the minor strain (e2) direction.5.3.2.3 In the tension test deformation process, the minor strains (e2) are negative, and the test specimen is narrowed both through the thickness and across its width.5.3.3 These strains are plotted on a forming limit diagram (FLD), and the forming limit curve (FLC) is drawn to connect the highest measured e1 and e2 strain combinations that include good data points.5.3.3.1 When there is intermixing and no clear distinction between good and marginal data points, a best fit curve is established to follow the maximum good data points as the FLC.5.3.4 The forming limit is established at the maximum major strain (e1) attained prior to necking.5.3.5 The FLC defines the limit of useful deformation in forming metallic sheet products.5.3.6 FLCs are known to change with material (specifically with the mechanical or formability properties developed during the processing operations used in making the material) and the thickness of the sheet metal.5.3.6.1 The strain hardening exponent (n value), defined in Test Method E646, affects the forming limit. A high n value will raise the limiting major strain (e1), allowing more stretch under positive minor strain conditions (e2 > 0).5.3.6.2 The plastic strain ratio (r value), defined in Test Method E517, affects the capacity of a material to be deep drawn. A high r value will move the minor strain (e2) into a less severe area to the left of the FLDo (e2 < 0), thus permitting deeper draws for a given major strain (e1).5.3.6.3 The thickness of the material will affect the FLC since a thicker test specimen has more volume to respond to the forming process.5.3.6.4 The properties of the steel sheet product used in determining the FLC of Fig. 3 included the n value and the r value.5.3.7 FLCs serve as a diagnostic tool for material strain analysis and have been used for evaluations of stamping operations and material selection.5.3.8 The FLC provides a graphical basis for comparison with strain distributions on parts formed by sequential press operations.5.3.9 The FLC obtained by this method follows a constant proportional strain path where there is a nominally fixed ratio of major (e1) to minor (e2) strain.5.3.9.1 There is no interrupted loading, or reversal of straining, but the rate of straining may be slowed as the test specimen approaches necking or fracture.5.3.9.2 The FLC can be used for conservatively predicting the performance of an entire class of materials provided the n value, r value, and thickness of the material used are representative of that class.5.3.10 Complex forming operations, in which the strain path changes, or the strain is not homogeneous through the metal sheet thickness, can produce limiting strains that do not agree with the forming limit obtained by this method.5.3.11 Characterization of a material's response to plastic deformation can involve strain to fracture as well as to the onset of necking. These strains are above the FLC.5.3.12 The FLC is not suitable for lot-to-lot quality assurance testing because it is specific to that sample of a material which is tested to establish the forming limit.1.1 This test method gives the procedure for constructing a forming limit curve (FLC) for a metallic sheet material by using a hemispherical deformation punch test and a uniaxial tension test to quantitatively simulate biaxial stretching and deep drawing processes.1.1.1 Fig. 1 shows an example of a forming limit curve on a schematic forming limit diagram (FLD).FIG. 1 Schematic Forming Limit DiagramNOTE 1: The upper curve represents the forming limit curve. Strains below the lower curve do not occur during forming metallic sheet products in the most stamping press operations. Curves to the left of % e2 = 0 are for constant area of the test specimen surface.1.2 FLCs are useful in evaluating press performance by metal fabrication strain analysis.1.3 The method applies to metallic sheet from 0.5 mm (0.020 in.) to 3.3 mm (0.130 in.).1.4 The values stated in SI units are to be regarded as the standard. The values given in parentheses after SI units are provided for information only and are not considered standard.1.5 This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility of the user of this standard to establish appropriate safety, health, and environmental practices and determine the applicability of regulatory limitations prior to use.1.6 This international standard was developed in accordance with internationally recognized principles on standardization established in the Decision on Principles for the Development of International Standards, Guides and Recommendations issued by the World Trade Organization Technical Barriers to Trade (TBT) Committee.

定价： 646元 / 折扣价： 550 元 加购物车