定价： 345元 / 折扣价： 294 元 加购物车

3.1 Standard reference materials are used for calibration and verification of many carbon black tests under the jurisdiction of D24. This practice defines a systematic means of naming these reference materials and does so in a manner to clearly differentiate between the various reference materials as well as their version.1.1 This classification covers instructions for naming the reference materials used by Committee D24.1.2 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.1.3 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

定价： 819元 / 折扣价： 697 元 加购物车

1.1 This descriptive nomenclature is intended to give accurate descriptions of some common or important naturally occurring and synthetic constituents of aggregates for radiation-shielding concrete, that, at the same time, are not common or important constituents of concrete aggregates in general use. While most of the minerals and rocks discussed below may occur in small quantities in aggregates in general use, they are not major constituents of such aggregates. Common constituents of aggregates in general use are described in Descriptive Nomenclature C294. Radiation-shielding concrete often contains such aggregates, but other special aggregates are used in some circumstances.1.2 The synthetic aggregates included are ferrophosphorus and boron frit.1.3 The descriptions are not adequate to permit the identification of materials, since accurate identification of natural and synthetic aggregate constituents in many cases can only be made by a qualified geologist, mineralogist, or petrographer, using the apparatus and procedures of those sciences.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 The text of this standard refers to notes and footnotes that provide explanatory material. These notes and footnotes (excluding those in tables and figures) shall not be considered as requirements of this standard.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

4.1 This descriptive nomenclature provides information on terms commonly applied to concrete aggregates. This standard is intended to assist in understanding the meaning and significance of the terms.4.2 Many of the materials described frequently occur in particles that do not display all the characteristics given in the descriptions, and most of the described rocks grade from varieties meeting one description to varieties meeting another with all intermediate stages being found.4.3 The accurate identification of rocks and minerals can, in many cases, be made only by a qualified geologist, mineralogist, or petrographer using the apparatus and procedures of these sciences. Reference to these descriptions may, however, serve to indicate or prevent gross errors in identification. Identification of the constituent materials in an aggregate may assist in characterizing its engineering properties, but identification alone cannot provide the sole basis for predicting behavior of aggregates in service. Aggregates of any type or combination of types may perform well or poorly in service depending upon the exposure to which the concrete is subjected, the physical and chemical properties of the matrix in which they are embedded, their physical condition at the time they are used, and other factors. Constituents that may occur only in minor amounts in the aggregate may or may not decisively influence its performance. Information about concrete aggregate performance in concrete has been published by ASTM.41.1 This descriptive nomenclature provides brief descriptions of some of the more commonly occurring, or more important, natural and artificial materials of which mineral aggregates are composed. The descriptions provide a basis for understanding these terms as applied to concrete aggregates. When appropriate, brief observations regarding the potential effects of using the natural and artificial materials in concrete are discussed.NOTE 1: These descriptions characterize minerals and rocks as they occur in nature and blast-furnace slag or lightweight aggregates that are prepared by the alteration of the structure and composition of natural material. Information about lightweight aggregates is given in Specifications C330, C331, and C332.1.2 This standard does not include descriptions of constituents of aggregates used in radiation shielding concrete. See Descriptive Nomenclature C638.1.3 The values stated in SI units are to be regarded as standard. No other units of measurement are included in this standard.1.4 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： 646元 / 折扣价： 550 元 加购物车

1. Scope This International Standard establishes the classification of the major types of winches and rope anchors and the nomenclature for major components and parts peculiar to these machines. Examples used here are not intended to include all exis

定价： 319元 / 折扣价： 272 元

An essential requirement of hydrogeologists in evaluating the hydraulic properties of a segment of earth materials is to define and map hydrogeologic units, aquifers, and confining units, which are determined on the basis of relative permeability. Discussion of the hydrogeologic units is facilitated by individual designations (see Practices D5409, D5434, and D5474).Determinations of hydrogeologic units are based on indirect methods, knowledge of the geologic materials (geologic mapping, surface geophysical surveys, borehole geophysical logs, drill-cuttings and core descriptions, and so forth), and hydraulic testing (aquifer tests, laboratory permeability tests on core samples, and so forth).The physical properties of all rock units will change if traced laterally and vertically. The rock units are broken by unconformities and faults, which may or may not affect the flow of groundwater. The process of designating and naming aquifers and confining units, therefore, is a somewhat subjective undertaking, and, if not thoroughly documented, can lead to confusion.Guidelines for naming aquifers can help avoid some of the confusion and problems associated with hydrogeologic studies if the guidelines are straight forward to apply, flexible, and applicable to studies of a variety of scales from site-specific to regional.The guidelines that follow include discussions of the terminology of aquifer nomenclature, the definition of the hydrogeologic framework, the suggested procedures for naming aquifers, and examples of naming aquifers.These guidelines have resulted from numerous discussions on the subject of aquifer nomenclature among hydrogeologists. Although unanimous agreement on these proposals has not been achieved, the exercises provided an extremely useful purpose in creating additional thought and discussion.1.1 This guide covers a series of options but does not specify a course of action. It should not be used as the sole criterion or basis of comparison and does not replace or relieve professional judgement.1.2 This guide contains instructions and suggestions for authors of groundwater (hydrogeologic) reports in assigning appropriately derived and formatted aquifer nomenclature. Discussed are the water-bearing units that may require name identification, which are, ranked from largest to smallest, aquifer system, aquifer, and zone. Guidance is given on choosing the source of aquifer names, those are from lithologic terms, rock-stratigraphic units, and geographic names.1.3 Included are examples of comparison charts and tables that can be used to define the hydrogeologic framework. Illustrations of eleven different hypothetical aquifer settings are presented to demonstrate the naming process.1.4 Categories of items not suggested as a source of aquifer names are reviewed because, although they should be avoided, they occur in published documents. These categories are the following: time-stratigraphic names, relative position, alphanumeric designations, depositional environment, depth of occurrence, acronyms, and hydrologic conditions.1.5 Confining units are discussed with the suggestion that these units should not be named unless doing so clearly promotes an understanding of a particular aquifer system. Suggested sources of names for confining units correspond to those for aquifer names, which are lithologic terms, rock-stratigraphic units, and geographic names.1.6 It is suggested that in reports that involve hydrogeology, the author should consider first not naming aquifers (see 6.2).1.7 Format and expression styles are assessed along with the general cautions related to name selection of aquifers and confining units.1.8 This guide is a modification of a previously published report (1).1.9 This guide offers an organized collection of information or a series of options and does not recommend a specific course of action. This guide cannot replace education or experience and should be used in conjunction with professional judgment. Not all aspects of this guide may be applicable in all circumstances. This guide is not intended to represent or replace the standard of care by which the adequacy of a given professional service must be judged, nor should this guide be applied without consideration of a project's many unique aspects. The word “Standard” in the title of this document means only that the document has been approved through the ASTM consensus process.

定价： 0元 / 折扣价： 0 元

This practice covers the rules for naming one, two, or three-piece round wire leads used as conductors through glass seals in electron tubes, excluding stranded leads and leads for semiconductors. Each portion of designation should be separated by a dash (-). Materials for a component lead are generally designated using the chemical symbols. Claddings or platings are represented by numerical suffixes at the end of the material designation preceded by "C" (coating). For alloys that are unspecified, a numerical value between chemical symbols indicates the percent content of the material preceding the value. Descriptive suffixes are used to specify annealing conditions.1.1 This practice covers rules for designating one, two, or three-piece round wire leads used as conductors through glass seals in electron tubes. Stranded leads and leads for semiconductors are excluded.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.1.4 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： 0元 / 折扣价： 0 元

4.1 The purpose of this standard is to provide common tree names and botanical names for commercial species and species groups but is not intended to be all inclusive of commercial practice. The decision about which commercial species are included in this practice is made by the D07 committee on wood.4.2 Individual species are frequently mixed in commercial species groups for marketing or harvesting convenience, or for similar appearance or performance properties, or both.4.3 Consumers of lumber, plywood, and other wood-based products may use different mixes of species for the same species group name. This practice should provide clarity for nomenclature used throughout wood-consuming industries.1.1 Commercial species group names are listed with common tree and botanical names. Commercial names are representative of commercial practice in the United States and Canada. Some foreign species that are used in the United States and Canada are listed in Appendix X1 with their commercial and botanical names.1.2 The official common names conform to USFS AH 541. In addition to the official common name for a species, the checklist also lists other names by which the species and the lumber produced from it are sometimes designated. Names unique to Canada are shown with an *. The names recognized under the American Lumber Standard are shown with a dagger (†).1.3 The designations in parentheses, (North) and (South), a convention used by the American Lumber Standard Committee (ALSC) accredited lumber rules writing agencies listed in PS 20, identify a commercial name applied only when the included species are harvested from Canada as (North) or the United States as (South).1.4 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： 646元 / 折扣价： 550 元 加购物车

定价： 689元 / 折扣价： 586 元 加购物车