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Field Solutions to Common Valve Assembly Problems and Pressure Inspection and Test Standards
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作者 JINXiaofeng WANGXinhua 《外文科技期刊数据库(文摘版)工程技术》 2022年第6期140-145,共6页
This paper introduces the common technical problems in the assembly process of gate valve, globe valve and swing check valve, analyzes the causes, and according to different reasons, gives the solutions and measures f... This paper introduces the common technical problems in the assembly process of gate valve, globe valve and swing check valve, analyzes the causes, and according to different reasons, gives the solutions and measures for the field assembly of valves. This paper introduces the pressure test inspection requirements of gate valves, globe valves and swing check valves and the determination of leakage methods. Introduce the common domestic and foreign standards for valve pressure test and leakage inspection. 展开更多
关键词 VALVE assembly technology SOLUTIONS pressure check pressure test standard
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Test Standards for Direct Steam Generating Solar Concentrators
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作者 Mahesh M. Rathore Ravi M. Warkhedkar 《Journal of Power and Energy Engineering》 2015年第12期1-10,共10页
There are a few standards reported in the literature for testing and evaluation of thermal performance of solar concentrators based on sensible heating of working fluid. The preceding standard measures only the cookin... There are a few standards reported in the literature for testing and evaluation of thermal performance of solar concentrators based on sensible heating of working fluid. The preceding standard measures only the cooking efficiency and cooking capacity. Apart from thermal efficiency, there is an imperative need for other important parameters of the solar concentrators such as its stagnation temperature, cooking capacity, cost per watts delivered, weight of the cooker, ease of handling and aesthetics. The characterization of a concentrator at its operating temperature settles appropriate size and type of concentrator for any thermal application. The performance test is conducted at Chandwad (20.3292°N, 74.2444°E), Maharashtra and the proposed protocol aims for evaluation of thermal performance of solar cooking system and standardization of reporting the test results so that anyone can easily recognize and use it. 展开更多
关键词 Solar CONCENTRATOR testS Efficiency COOKING Power standardIZATION in testS and REPORTING
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Innovative Application of Automatic Test Equipment in the Control Board Testing of Household Appliances
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作者 Wei Huang 《Journal of Electronic Research and Application》 2025年第5期249-255,共7页
This article introduces the composition and working principle of home appliance control board automation testing equipment,elaborates on the importance of key technical indicators,explains the integrated design of fun... This article introduces the composition and working principle of home appliance control board automation testing equipment,elaborates on the importance of key technical indicators,explains the integrated design of functional modules,signal processing modules,and data analysis modules,and covers aspects such as the application of machine learning algorithms and the establishment of fault waveform databases.Finally,it looks forward to the development of intelligent testing systems and emphasizes the importance of building a standardized testing system. 展开更多
关键词 Home appliance control board Automated test test standard
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Quality and Testing Standards on Rice Production in China and Development Strategies
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作者 XIE LiHong CHEN Neng DUAN BinWu 《China Standardization》 2006年第3期16-20,共5页
China is the biggest country of rice production and consumption in the world;more than 50% of the population feeds chiefly on rice. The quality of rice and its role as a staplefood carry much weight. The rice qualitie... China is the biggest country of rice production and consumption in the world;more than 50% of the population feeds chiefly on rice. The quality of rice and its role as a staplefood carry much weight. The rice qualities are those aspects concerning processing, appearance,cooking, nutrition and safety of the product. The study, formulation and implementation of standardson rice qualities and testing bear heavily on the improving of rice qualities, human health,substitution of rice varieties, promoting quality rice production and regulating rice market. 展开更多
关键词 RATE Quality and testing standards on Rice Production in China and Development Strategies
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Overview of Standardized Testing System for ESL Students in U.S. Kindergarten Thru Grade 12 Public Schools
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作者 Volkan Cicek 《Sino-US English Teaching》 2011年第12期773-786,共14页
A comprehensive overview of standardized testing system for ESL (English as a Second Language) students in U.S kindergarten thru grade 12 public school system is reviewed within the context of basis on federal and s... A comprehensive overview of standardized testing system for ESL (English as a Second Language) students in U.S kindergarten thru grade 12 public school system is reviewed within the context of basis on federal and state laws, as well as instructional basis. Identification process of LEP (Limited English Proficient) students via nomination, testing and testing criteria to be identified as LEP, hence ESL if placed in the program is defined in detail Standardized testing process of these students based on the federal AYP (Adequate Yearly Progress) measures through regular state standardized tests depending on three types of instructional program that LEP student is placed in the school that are Bilingual Education Program, ESL Program, and Two-Way Immersion Dual Language Programs are described. Standardized testing process of these students based on the federal AYP measures through other means if exempted from regular state standardized tests such as LAT (Linguistically Accommodated Testing) and the conditions to be exempted are discussed in detail. Holistically rated English Language Proficiency Assessments that are implemented to fulfill federal AMAOs (Annual Measurable Achievement Objectives) measures are defined briefly. Physical features of LAT test as well as direct and indirect accommodations for LAT reading, mathematics and science tests are defined via the accommodation needed and the type of assistance provided. Lastly, testing criteria to exit LEP status and other issues concerning exiting LEP status are reviewed 展开更多
关键词 ESL (English as a Second Language) bilingual education LEP (Limited English Proficient) LanguageProficiency Assessment linguistics accommodations direct and indirect accommodations standardized testing
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Discussion on the Integration and Innovation of Food Testing Standards
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作者 LYUDongming ZOUFeng 《外文科技期刊数据库(文摘版)自然科学》 2022年第5期054-058,共5页
Based on the analysis of food testing standards (according to parameters, categories and methods), this paper puts forward an integrated reference method for food testing standards. At the same time, the innovation of... Based on the analysis of food testing standards (according to parameters, categories and methods), this paper puts forward an integrated reference method for food testing standards. At the same time, the innovation of food testing methods puts forward some "normal" requirements from aspects of coverage, recovery rate and consistency with determination standards. 展开更多
关键词 food testing standards parameters CATEGORIES COVERAGE recovery rate
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Obtaining 2D Soil Resistance Profiles from the Integration of Electrical Resistivity Data and Standard Penetration Test (SPT) and Light Dynamic Penetrometer (DPL) Resistance Tests—Applications in Mass Movements Studies
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作者 Cassiano Antonio Bortolozo Tatiana Sussel Gonçalves Mendes +10 位作者 Mariana Ferreira Benessiuti Motta Silvio Jorge Coelho Simões Tristan Pryer Daniel Metodiev Marcio Roberto Magalhães de Andrade Maiconn Vinicius de Moraes Danielle Silva de Paula Nélio José Bastos Luana Albertani Pampuch Rodolfo Moreda Mendes Marcio Augusto Ernesto de Moraes 《International Journal of Geosciences》 2023年第9期840-854,共15页
In Brazil and various regions globally, the initiation of landslides is frequently associated with rainfall;yet the spatial arrangement of geological structures and stratification considerably influences landslide occ... In Brazil and various regions globally, the initiation of landslides is frequently associated with rainfall;yet the spatial arrangement of geological structures and stratification considerably influences landslide occurrences. The multifaceted nature of these influences makes the surveillance of mass movements a highly intricate task, requiring an understanding of numerous interdependent variables. Recent years have seen an emergence in scholarly research aimed at integrating geophysical and geotechnical methodologies. The conjoint examination of geophysical and geotechnical data offers an enhanced perspective into subsurface structures. Within this work, a methodology is proposed for the synchronous analysis of electrical resistivity geophysical data and geotechnical data, specifically those extracted from the Light Dynamic Penetrometer (DPL) and Standard Penetration Test (SPT). This study involved a linear fitting process to correlate resistivity with N10/SPT N-values from DPL/SPT soundings, culminating in a 2D profile of N10/SPT N-values predicated on electrical profiles. The findings of this research furnish invaluable insights into slope stability by allowing for a two-dimensional representation of penetration resistance properties. Through the synthesis of geophysical and geotechnical data, this project aims to augment the comprehension of subsurface conditions, with potential implications for refining landslide risk evaluations. This endeavor offers insight into the formulation of more effective and precise slope management protocols and disaster prevention strategies. 展开更多
关键词 GEOPHYSICS Geotechnical Data Electrical Resistivity Method standard Penetration test (SPT) Light Dynamic Penetrometer (DPL) Mass Movements
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Application ofStandard Penetration Test(SPT) in Hydro- power Projects in Sudan
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作者 Zhang xiaoqiang Wanglei 《商情》 2010年第3期73-75,共3页
关键词 苏丹 数据定址存贮器 信息传达 差别
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A Usable Selection Range Standard Based on Test Suite Reduction Algorithms
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作者 MA Yanjun ZHAO Zhigang +1 位作者 LIANG Yuchen YUN Maojin 《Wuhan University Journal of Natural Sciences》 CAS 2010年第3期261-266,共6页
In this paper, we analyze the features and distinctions of 6 classical algorithms: greedy algorithm (G), greedy evolution algorithm (GE), heuristics algorithm (H), greedy heuristic G (GRE), integer linear pro... In this paper, we analyze the features and distinctions of 6 classical algorithms: greedy algorithm (G), greedy evolution algorithm (GE), heuristics algorithm (H), greedy heuristic G (GRE), integer linear programming algorithm (ILP) and genetic algorithm (GA) to ensure the main influencing factors-the performance of algorithms and the running time of algorithms. What's more, we would not only present a research design that aims at gaining deeper understanding about the algorithm classification and its function as well as their distinction, but also make an empirical study in order to obtain a practical range standard that can guide the selection of reduction algorithms. When the size of a test object (product of test requirements and test cases) is smaller than 2000×2000, G algorithm is the commonly recommended algorithm. With the growth of test size, the usage of GE and GRE becomes more general. 展开更多
关键词 test suite reduction algorithms influencing factor selection standard
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化浊散结除痹颗粒的制备工艺优化研究
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作者 王美玲 彭斯伟 +7 位作者 张英杰 肖艳 杨瑞芳 陈冰燕 杨帆 陈鹏 苏友新 郭洁梅 《中药新药与临床药理》 北大核心 2026年第2期332-342,共11页
目的优化化浊散结除痹颗粒的制备工艺。方法采用超高效液相色谱(UPLC)建立化浊散结除痹颗粒复方多成分含量测定方法,以新异落新妇苷、异落新妇苷、新落新妇苷、落新妇苷、盐酸小檗碱的转移率、出膏率为评价指标,通过单因素试验结合正交... 目的优化化浊散结除痹颗粒的制备工艺。方法采用超高效液相色谱(UPLC)建立化浊散结除痹颗粒复方多成分含量测定方法,以新异落新妇苷、异落新妇苷、新落新妇苷、落新妇苷、盐酸小檗碱的转移率、出膏率为评价指标,通过单因素试验结合正交试验考察提取时间、加水量、提取次数对化浊散结除痹颗粒提取工艺的影响;采用休止角测定、辅料筛选及工艺验证优选化浊散结除痹颗粒的成型工艺,并通过中试试验验证化浊散结除痹颗粒的工艺。结果化浊散结除痹颗粒优选的制备工艺为:化浊散结除痹方各饮片加热回流提取2次,第一次加12倍水,提取1.5 h;第二次加12倍水,提取1.0 h;合并药液,减压浓缩至相对密度1.07~1.08 g·cm^(3)的浓缩液(65~75℃);加入5%麦芽糊精,喷雾干燥(进风温度175~185℃、出风温度90~100℃);加入干膏粉质量的0.3%二氧化硅、0.1%硬脂酸镁及麦芽糊精适量,混合均匀后干法制粒,整粒分装。中试试验制备的3批化浊散结除痹颗粒各项评价指标良好,且批次间差异小。结论优选的化浊散结除痹颗粒制备工艺稳定、可靠,可为该颗粒剂的工艺标准化奠定研究基础。 展开更多
关键词 化浊散结除痹颗粒 超高效液相色谱 正交试验 制备工艺优化 单因素试验 工艺标准化
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GB/T 5453-1997《纺织品 织物透气性的测定》的实验室能力验证
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作者 穆莲娟 狄宏静 吴倩 《上海纺织科技》 2026年第2期54-57,共4页
通过验证纺织品透气性检测的能力,了解实验室对GB/T 5453—1997《纺织品织物透气性的测定》标准的理解和掌握程度。拟订作业指导书并评价样品的均匀性及稳定性,采用经典统计方法分析并确定指定值和能力评定标准差。结果显示:能力验证样... 通过验证纺织品透气性检测的能力,了解实验室对GB/T 5453—1997《纺织品织物透气性的测定》标准的理解和掌握程度。拟订作业指导书并评价样品的均匀性及稳定性,采用经典统计方法分析并确定指定值和能力评定标准差。结果显示:能力验证样品可满足均匀性和稳定性要求,参加实验室共33家,结果满意30家,不满意3家。不满意实验室对于标准理解和设备操作的掌握不足,须做好分析及整改,提升能力水平。 展开更多
关键词 透气性 纺织品检测 能力验证 标准
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2016版OEKO-TEX Standard 100标准的变化 被引量:2
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作者 潘文丽 《染整技术》 CAS 北大核心 2016年第8期43-48,共6页
纺织品的生态测试已经成为化学安全控制的必然趋势,为了了解纺织品最新的环保测试要求,必须不断跟进并掌握国际生态纺织品的发展动态。Okeo-Tex 100在2016年1月发布了最新版本,与2015年版本相比,有了多处修改,对其做了全面的分析。
关键词 测试标准 生态纺织品
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国内外充气救援艇标准对比研究
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作者 邢瑞泽 姜楠 +2 位作者 李国辉 任常兴 田文杰 《消防科学与技术》 北大核心 2026年第2期93-97,105,共6页
本文聚焦于充气救援艇,对国际海事组织、国际标准化组织、欧盟以及日本等主要国际组织及代表性国家的标准与我国标准进行了比较分析。从国内外充气艇的标准化工作及主要性能指标的检测标准入手,发现我国的充气艇标准大多引用或借鉴了国... 本文聚焦于充气救援艇,对国际海事组织、国际标准化组织、欧盟以及日本等主要国际组织及代表性国家的标准与我国标准进行了比较分析。从国内外充气艇的标准化工作及主要性能指标的检测标准入手,发现我国的充气艇标准大多引用或借鉴了国际海事组织和国际标准化组织标准,并在检测内容上做了相应的调整,使其更贴合中国需求,但缺乏针对救援性能的特定检测指标和方法,这限制了充气艇在水域救援领域的应用和发展。结合水域救援的特点,总结了充气艇在救援过程中的一系列性能需求,并提出了充气艇在快速性、安全抛落性能、自扶正等方面的性能指标及检测方法。 展开更多
关键词 充气式救援艇 标准对比 检测方法
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文献A Successful Strategy for Satellite Development and Testing点评 被引量:1
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作者 冯振兴 《航天器环境工程》 2009年第3期278-286,200,共9页
文章对美国在1998-2002年执行"快,好,省"采购改革方案期间航天器故障率上升146%的3个原因进行了分析与点评。这3个原因包括:对标准、规范严格遵循的意识下降;航天元器件复合度激增;系统工程管理失控。文章对抑制故障率上升的... 文章对美国在1998-2002年执行"快,好,省"采购改革方案期间航天器故障率上升146%的3个原因进行了分析与点评。这3个原因包括:对标准、规范严格遵循的意识下降;航天元器件复合度激增;系统工程管理失控。文章对抑制故障率上升的对策进行归纳,其中最重要的一条是:卫星研制工作必须严谨,一丝不苟地按照相关标准进行(环境)试验。 展开更多
关键词 卫星 环境试验 规范 标准 可靠性
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探究中医体质辨析和体质健康测试在儿童青少年近视防控中的作用
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作者 陈楠 杨迎新 +2 位作者 亢泽峰 王健全 杨潮 《中国中医眼科杂志》 2026年第1期56-60,93,共6页
中医体质学说认为,偏颇体质会对儿童青少年体质健康产生负面影响,同时会综合影响其近视的发生发展。体质健康测试成绩较低的儿童青少年与近视儿童青少年的中医偏颇体质分布大体一致,主要集中在气虚质、阳虚质、痰湿质,这可能与不健康的... 中医体质学说认为,偏颇体质会对儿童青少年体质健康产生负面影响,同时会综合影响其近视的发生发展。体质健康测试成绩较低的儿童青少年与近视儿童青少年的中医偏颇体质分布大体一致,主要集中在气虚质、阳虚质、痰湿质,这可能与不健康的生活方式有关,如长期不良的读写姿势、频繁的近距离用眼、低体力活动水平等。中医体质学“未病先防,既病防变”的理念在近视防控中尤为重要,偏颇体质和较低的体质健康测试成绩与儿童青少年近视发生发展存在相关性。基于此,本文总结分析儿童青少年近视与中医体质辨析和体质健康测试的关系,提出“体质内存、体测外显”,两者结合的新思路,为中医药以及中医适宜技术防控儿童青少年近视提供理论基础。 展开更多
关键词 近视 中医体质 国家学生体质健康标准测试 儿童 青少年
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燃料电池发动机性能测试标准现状综述
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作者 朱刚 陈洲 《标准科学》 2026年第2期84-93,144,共11页
[目的]分析当前燃料电池发动机性能测试领域存在的主要问题,以明确研究重点并推动我国燃料电池产业化发展。[方法]通过系统调研国内外燃料电池发动机性能测试方法与评估体系,对比分析了现有技术方案的差异性与适用性,梳理了燃料电池发... [目的]分析当前燃料电池发动机性能测试领域存在的主要问题,以明确研究重点并推动我国燃料电池产业化发展。[方法]通过系统调研国内外燃料电池发动机性能测试方法与评估体系,对比分析了现有技术方案的差异性与适用性,梳理了燃料电池发动机性能检测技术的发展现状与关键挑战。[结果]揭示了当前性能测试方法分散、评价标准不统一等问题,总结了国内外测试体系的异同,提出了建立统一性能测评标准的必要性与可行性。[结论]统一且规范的性能测试方法与评价体系对燃料电池技术发展至关重要,为推动行业标准制定、加速燃料电池产业化进程提供理论支撑与实践参考。 展开更多
关键词 燃料电池发动机 测试标准 耐久性 性能指标
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全程曲线拟合法和Aquifertest水文地质求参 被引量:8
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作者 杜川 梁秀娟 +2 位作者 张茜 陈章 李文娟 《人民黄河》 CAS 北大核心 2014年第4期19-21,25,共4页
抽水试验是获取含水层水文地质参数的主要方法,求参结果直接影响对调查区水文地质条件的认识和地下水开发利用。传统求参方法存在主观影响大、求参时间长、易受外界影响和抽水阶段数据的不足等问题。通过全程曲线拟合法和Aquifertest软... 抽水试验是获取含水层水文地质参数的主要方法,求参结果直接影响对调查区水文地质条件的认识和地下水开发利用。传统求参方法存在主观影响大、求参时间长、易受外界影响和抽水阶段数据的不足等问题。通过全程曲线拟合法和Aquifertest软件分别从配线法和水位恢复法两个角度进行求参,并结合全程曲线拟合法确定最终取值。结果表明,采用Aquifertest软件求参便捷、准确,与水位恢复法求参结果的差异相对较小,全程曲线拟合法求参值具有唯一性和可靠性,多种方法结合求参能更真实反映水文地质情况。 展开更多
关键词 抽水试验 水文地质参数 Aquifertest软件 配线法 水位恢复法 全程曲线拟合法
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建筑通风与空调工程现场检测技术分析
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作者 徐转运 《中国厨卫》 2026年第2期194-196,共3页
文章针对建筑通风与空调系统的现场检测方法展开相关研究,系统阐述了风量、温湿度、漏风量、机组性能系数(COP)、水系统回水温度一致性及供、回水温差以及水泵效率等关键参数的测试原理与方法;同时讨论了当前现场检测的难点,并提出了具... 文章针对建筑通风与空调系统的现场检测方法展开相关研究,系统阐述了风量、温湿度、漏风量、机组性能系数(COP)、水系统回水温度一致性及供、回水温差以及水泵效率等关键参数的测试原理与方法;同时讨论了当前现场检测的难点,并提出了具体的应对措施。此外,进一步引进了不确定度概念,结合风量检测实例阐明了不确定度在建筑通风与空调系统现场检测中的应用,以期为提升现场检测技术手段、优化建筑通风与空调系统的设计施工与验收流程提供参考价值。 展开更多
关键词 建筑通风与空调 现场检测 检测标准 技术参数 不确定度
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国内外海洋降解塑料检测与评价标准
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作者 朱佳欢 石鎏杰 孙梦捷 《上海包装》 2026年第1期27-29,49,共4页
海洋塑料污染是全球性环境问题,海洋降解塑料作为治理手段之一受到广泛关注。系统梳理了国内外海洋降解塑料的检测与评价标准体系。对比分析了中国《生物降解塑料与制品降解性能及标识要求》(GB/T 41010—2021)、国际标准化组织ISO 2240... 海洋塑料污染是全球性环境问题,海洋降解塑料作为治理手段之一受到广泛关注。系统梳理了国内外海洋降解塑料的检测与评价标准体系。对比分析了中国《生物降解塑料与制品降解性能及标识要求》(GB/T 41010—2021)、国际标准化组织ISO 22403:2020和美国材料与试验协会ASTM D7081-05标准中对海洋降解塑料的定义,指出其核心要求均为材料在海洋环境中可完全降解为二氧化碳等小分子。综述了主要检测标准,按模拟环境(海水、沉积物、沉积物/海水界面及实际海洋环境)和检测指标(降解程度与崩解程度)进行分类比较,并指出国内标准多等同采用ISO标准。对比分析了上述三大评价标准在检测方法、指标要求等方面的异同,强调ASTM D6691是共同的方法依据。介绍了国内外认证标识体系,包括中国GB/T 41010—2021标识、TUV奥地利和德国DINCERTCO的认证标识。总结指出海洋降解塑料发展受限于海洋环境低温低微生物活性,材料选择有限,且中国尚缺专门评价标准和检测能力,未来须进一步完善体系以推动其应用。 展开更多
关键词 海洋降解塑料 检测标准 评价标准 认证标识 生物降解
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