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橡胶硫化工艺条件的优化选择 Ⅱ.最佳硫化程度范围的确定
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作者 刘慧 陆永中 +2 位作者 史东建 徐新华 黄太仁 《常州大学学报(自然科学版)》 CAS 1993年第Z1期11-19,共9页
本文提出了确定橡胶最佳硫化程度范围的一整套简单可行的实验和计算方法。它包括用平板硫化机测定胶料导热系数和制备测试试样的实验,以及用有限差分的方法计算试样的温度场和硫化程度场。后者的计算借助于发展了Coran模式和由此测定的... 本文提出了确定橡胶最佳硫化程度范围的一整套简单可行的实验和计算方法。它包括用平板硫化机测定胶料导热系数和制备测试试样的实验,以及用有限差分的方法计算试样的温度场和硫化程度场。后者的计算借助于发展了Coran模式和由此测定的动力学参数,用计算确定了硫化程度的试样测定其力学性能,从而选择了最佳硫化温度和该温度下的最佳硫化程度范围,这为预测不同工艺方式,不同形状、尺寸制品的最佳硫化时间范围找到依据。 展开更多
关键词 一维传热 有限差分 最佳硫化程度范围 最佳硫化时间范围
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糖尿病足严重程度连续分级创面菌群组成
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作者 蔡玉兰 阳琰 +5 位作者 岳瑜 牟芝群 姚杨 胡皓铭 吴旻 邓嘉杰 《中国老年学杂志》 CAS 北大核心 2024年第5期1079-1083,共5页
目的 分析糖尿病足(DF)严重程度连续分级创面菌群组成差异。方法 随机纳入80例DF患者分为足部血流、受影响范围、严重程度、感染、感觉能力(PEDIS)1~4级组各20例。清创后采集创面深部感染组织标本,利用16S rRNA高通量测序技术分析创面... 目的 分析糖尿病足(DF)严重程度连续分级创面菌群组成差异。方法 随机纳入80例DF患者分为足部血流、受影响范围、严重程度、感染、感觉能力(PEDIS)1~4级组各20例。清创后采集创面深部感染组织标本,利用16S rRNA高通量测序技术分析创面菌群组成,探索各组菌群差异及Marker菌群。结果 随着DF创面PEDIS分级的增加,创面菌群中厚壁菌门及放线菌门的丰度逐渐降低,而拟杆菌门的丰度逐渐增加,在PEDIS 4级创面中丰度最高。随着PEDIS分级的增加,创面中普氏菌属、厌氧球菌属、拟杆菌属、戈尔德菌属的丰度逐渐增加,链球菌属、葡萄球菌属的丰度逐渐降低。PEDIS 1~4级组的Marker菌门分别是厚壁菌门、厚壁菌门、变形菌门及拟杆菌门,Marker菌属分别是链球菌属、厌氧球菌属/葡萄球菌属、克雷伯菌属及普氏菌属。结论 随着DF创面PEDIS分级的增加,G-厌氧菌丰度逐渐增加,G+需氧菌丰度逐渐降低。 展开更多
关键词 糖尿病足 足部血流、受影响范围、严重程度、感染、感觉能力(PEDIS)分级 16S rRNA测序 菌群
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我国财务会计目标实现程度与实现范围的探讨
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作者 梁志杰 《科技创新与应用》 2011年第19期194-194,共1页
运用主观与客观,可论性与现实性的基本原理论证了财务会计目标作为开展财务会计活动的前提条件和评价财务会计活动成败优劣的基本标准。
关键词 财务会计 内涵 实现 范围程度
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撕拉性离断血管损伤范围的实验观测 被引量:7
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作者 尚剑 张信英 +2 位作者 毕郑刚 杨群 曹杨 《中国修复重建外科杂志》 CAS CSCD 2000年第3期135-138,共4页
目的 测定撕拉性离断血管损伤的程度和范围。方法 大白兔 2 0只 ,随机分为切割性离断组 (A组 )和撕拉性离断组 (B组 )。以肉眼、手术显微镜、光镜和电镜测定每组动物血管损伤的程度和范围。分别于再植后3及 10天探查 ,统计通畅率并比... 目的 测定撕拉性离断血管损伤的程度和范围。方法 大白兔 2 0只 ,随机分为切割性离断组 (A组 )和撕拉性离断组 (B组 )。以肉眼、手术显微镜、光镜和电镜测定每组动物血管损伤的程度和范围。分别于再植后3及 10天探查 ,统计通畅率并比较两组的愈合过程。结果  A组血管断端平齐 ,三层壁损伤范围一致 ,于断端 1mm范围以上管壁基本正常。 B组损伤重 ,内皮细胞缺失 ,内弹力层呈“跳跃样”破坏。在手术显微镜下观察正常部位以外 2~ 3mm仍有损伤。结论 撕拉性离断的血管损伤不规则 ,范围广。清创时应在显微镜下观察正常的部位外再切除 2~ 3mm,以保证管壁的完整。 展开更多
关键词 撕拉性离断 血管损伤 程度范围 断指血管损伤
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基于QPSO的多因素影响下系统故障概率变化程度研究 被引量:4
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作者 崔铁军 李莎莎 《安全与环境学报》 CAS CSCD 北大核心 2021年第5期1905-1910,共6页
为适应快速系统故障分析,在多因素影响下了解系统故障变化程度范围,预先判断故障变化速度趋势,在空间故障树(Space Fault Tree,SFT)理论框架下提出了一种基于量子粒子群优化算法(Quantum Particle Swarm Optimization,QPSO)的分析方法... 为适应快速系统故障分析,在多因素影响下了解系统故障变化程度范围,预先判断故障变化速度趋势,在空间故障树(Space Fault Tree,SFT)理论框架下提出了一种基于量子粒子群优化算法(Quantum Particle Swarm Optimization,QPSO)的分析方法。论述了QPSO的基本模型和步骤,在SFT中给出了描述系统故障概率变化的表达式,进而提出了多因素影响下系统故障概率变化程度范围的确定方法。方法适合于连续因素组成的连续空间中系统故障概率分布的优化,可实现单因素和多因素联合影响下的故障变化程度范围确定。使用经典算例进行分析,结果表明,算法得到的结果虽精度降低,但与传统解析结果相似,同时提高了分析速度。因此方法有利于系统故障的应急分析、预测和判断。 展开更多
关键词 安全系统工程 SFT QPSO 多因素影响 系统故障概率 变化程度范围
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血府逐瘀颗粒对犬心肌氧代谢及急性心肌梗死心外膜电图的影响
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作者 王秋静 刘洁 +1 位作者 刘芬 路航 《中国实验方剂学杂志》 CAS 2007年第11期24-26,共3页
目的:观察血府逐瘀颗粒(XFZHYG)对正常犬心肌氧代谢的影响,及对急性心肌梗死犬心外膜电图的影响。方法:将24只犬随机分为4组,每组各6只,第1组为生理盐水对照组,第2组为阳性对照药血府逐瘀口服液(XFZHYO)5.0 g.kg-1组,第3、4组分别为XFZH... 目的:观察血府逐瘀颗粒(XFZHYG)对正常犬心肌氧代谢的影响,及对急性心肌梗死犬心外膜电图的影响。方法:将24只犬随机分为4组,每组各6只,第1组为生理盐水对照组,第2组为阳性对照药血府逐瘀口服液(XFZHYO)5.0 g.kg-1组,第3、4组分别为XFZHYG(2.5,5.0 g.kg-1)小、大剂量组。采用麻醉开胸犬,测定心肌氧代谢参数,并结扎犬左冠状动脉前降支(LAD)复制急性心肌梗死模型,测定心肌缺血程度(∑-ST)和缺血范围(N-ST)。结果:2.5,5.0 g.kg-1XFZHYG与生理盐水对照组比较,心肌耗氧量和心肌氧摄取率减少(P<0.05,P<0.01)心肌缺血程度和范围明显下降(P<0.05,P<0.01)。结论:XFZHYG能降低心肌耗氧量和心肌氧摄取率,对缺血心肌具有保护作用。 展开更多
关键词 血府逐瘀颗粒 氧代谢 心肌梗死 心肌缺血程度范围
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浅析‘だけ’与‘はかり’的异同
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作者 谷宝祥 姜淼 《吉林化工学院学报》 CAS 2008年第5期87-89,共3页
‘ばかり’和‘だけ’均是日语副助词,在表示限定范围、程度方面,用法极其相近,意义也大体相同,一般情况下,‘ばかり’和‘だけ’是可以互换的。但语义和语感略有不同。本文拟就它们的异同点进行分析、探讨。
关键词 'ばかり’和'だけ’ 范围程度 语义和语感 异同点分析
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我国法律服务市场准入问题探析
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作者 柯秀丽 《河南司法警官职业学院学报》 2004年第2期42-44,共3页
市场准入原则是GATS中一个关键性条件 ,也是成员方履行WTO所规范的实现世界贸易自由化的首要义务。法律服务业属于专业服务 ,中国加入WTO后 ,应采取谈判方式逐步开放法律服务市场 ,因此研究法律服务业如何贯彻市场准入原则 ,以及市场准... 市场准入原则是GATS中一个关键性条件 ,也是成员方履行WTO所规范的实现世界贸易自由化的首要义务。法律服务业属于专业服务 ,中国加入WTO后 ,应采取谈判方式逐步开放法律服务市场 ,因此研究法律服务业如何贯彻市场准入原则 ,以及市场准入的现状、限度和范围 ,具有重要的现实意义。 展开更多
关键词 法律服务业 市场准入 程度范围
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Solubilities of Isophthalic Acid in Acetic Acid + Water Solvent Mixtures 被引量:3
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作者 成有为 霍磊 李希 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2013年第7期754-758,共5页
The solubilities of isophthalic acid (1) in binary acetic acid (2) + water (3) solvent mixtures were determined in a pressurized vessel. The temperature range was from 373.2 to 473.2K and the range of the mole ... The solubilities of isophthalic acid (1) in binary acetic acid (2) + water (3) solvent mixtures were determined in a pressurized vessel. The temperature range was from 373.2 to 473.2K and the range of the mole fraction of acetic acid in the solvent mixtures was from x2 = 0 to 1. A new method to measure the solubility was developed, which solved the problem of sampling at high temperature. The experimental results indicated that within the temperature range studied, the solubilities of isophthalic acid in all mixtures showed an increasing trend with increasing tem- perature. The expe^mental solubilities were co .rrelated by the Buchowski equation, and the calculate results showed good agreement with the experimental solubilities. Furthermore, the mixed solvent systems were found to exhibit a maximum solubility effect on the solubility, which may be attributed to the intermolecular association between the solute and the solvent mixture: The maximum solubility effect was well modeled by the modified Wilson equation. 展开更多
关键词 SOLUBILITY isophthalic acid acetic acid WATER solid-liquid equilibrium
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A natural language user interface for fuzzy scope queries 被引量:1
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作者 黄艳 俞宏峰 +1 位作者 耿卫东 潘支鹤 《Journal of Zhejiang University Science》 CSCD 2003年第2期152-161,共10页
This paper presents a two-agent framework to build a natural langua g e query interface for IC information system, focusing more on scope queries in a single English sentence. The first agent, parsing agent, syntact... This paper presents a two-agent framework to build a natural langua g e query interface for IC information system, focusing more on scope queries in a single English sentence. The first agent, parsing agent, syntactically p rocesses and semantically interprets natural language sentence to construct a fu zzy structured query language (SQL) statement. The second agent, defuzzif ying agent, defuzzifies the imprecise part of the fuzzy SQL statement into its e quivalent executable precise SQL statement based on fuzzy rules. The first agent can also actively ask the user some necessary questions when it manages to disa mbiguate the vague retrieval requirements. The adaptive defuzzification approach employed in the defuzzifying agent is discussed in detail. A prototype interface has been implemented to demonstrate the effectiveness. 展开更多
关键词 Integrated circuit information system Natural langua ge user interface GRAMMAR Fuzzy rule Matching degree
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Analysis of penetration acceleration signal based on wavelet transformation
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作者 王春常 顾强 安晓红 《Journal of Measurement Science and Instrumentation》 CAS CSCD 2015年第3期223-228,共6页
In order to analyze the composition and frequency distribution of acceleration signal in the process of projectile penetrating,this paper uses wavelet transform to decompose penetration acceleration signal to get the ... In order to analyze the composition and frequency distribution of acceleration signal in the process of projectile penetrating,this paper uses wavelet transform to decompose penetration acceleration signal to get the distribution of penetration acceleration signal in different frequency bands.Compared with the ideal acceleration signal curve and its characteristics,it can be concluded that the frequency range of the acceleration signal in the axis of the projectile and the vibration frequency range of the projectile are 31.25-62.5kHz and 62.5-125 kHz,respectively.Finally,the penetration acceleration signal curve is obtained by Simulink. 展开更多
关键词 penetration process wavelet transform ACCELERATION frequency distribution
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Hot compression deformation characteristics of Mg-Mn alloys
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作者 方超 张静 +3 位作者 廖爱林 薛绍展 袁付庆 潘复生 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2010年第10期1841-1845,共5页
The hot deformation behaviors of solution treated Mg-1.8Mn-0.4Er-0.2Al alloys were investigated by means of compression tests on Gleeble-1500 in strain rate range of 0.01-10s-1,deformation temperature range of 250-450... The hot deformation behaviors of solution treated Mg-1.8Mn-0.4Er-0.2Al alloys were investigated by means of compression tests on Gleeble-1500 in strain rate range of 0.01-10s-1,deformation temperature range of 250-450℃ and a true strain of 0.6.The constitutive relationships among flow stress,strain rate and deformation temperature were described by Arrhenius-type equations,based on the fact that the material constants could be calculated under a wide range of strains.The results show that the flow stress of the experimental alloy decreases with temperature increasing and strain rate decreasing.Under the experimental conditions,the products of constant α and n in the constitutive equation are stable within certain strains,and the deformation activation energy ranges from 160 to 220 kJ/mol.It is proved that the values of calculated flow stress are close to the experimental results with average error of 2.01%. 展开更多
关键词 magnesium alloy thermal deformation flow stress constitutive equation
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Hot-compression behavior of Al alloy 5182
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作者 唐建国 黄星星 张新明 《Journal of Central South University》 SCIE EI CAS 2012年第8期2073-2080,共8页
Hot-compression of aluminum alloy 5182 was carried out on a Gleeble- 1500 thermo-simulator at deformation temperature ranging from 350 ℃ to 500 ℃ and at strain rate from 0.01 s^-1 to 10 s^-1 with strain range from 0... Hot-compression of aluminum alloy 5182 was carried out on a Gleeble- 1500 thermo-simulator at deformation temperature ranging from 350 ℃ to 500 ℃ and at strain rate from 0.01 s^-1 to 10 s^-1 with strain range from 0.7 to 1.9. The microstructures and macro-textures evolution under different conditions were investigated by polarized optical microscopy and X-ray diffraction analysis, respectively. The basic trend is that the hot-compression stress increases with the decrease of temperature and increase of strain rate, which is revealed and elucidated in terms of Zener-Hollomon parameter in the hyperbolic sine equation with the hot-deformation activation energy of 143.5 kJ/mol. An empirical constitutive equation is proposed to predict the hot-deformation behavior under different conditions. As deformation temperature increases up to 400 ℃, at strain rate over 1 s^-1, dynamic recrystallization (DRX) occurs. Cube orientation { 100} (001) is detected in the recrystallized sample after hot-compression. 展开更多
关键词 aluminum alloy 5182 hot-compression TEXTURE MICROSTRUCTURE
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Analysis and evaluation of band-limited ray tracing method
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作者 WANG Rui SUN Jianguo 《Global Geology》 2018年第3期203-208,共6页
From the analysis and the contrast of band-limited ray tracing method based on Kirchhoff integral, it was found that the method performs many approximations in the derivation process and omits the derivative term of t... From the analysis and the contrast of band-limited ray tracing method based on Kirchhoff integral, it was found that the method performs many approximations in the derivation process and omits the derivative term of the phase factor in the Kirchhoff integral. Numerical calculations and analysis show that the omission of cor-relation terms in Kirchhoff integrals has a non-negligible effect on the calculation results, and the different terms in the Kirchhoff integral have different effects on different frequency ranges. The method can be applied to ve-locity models containing complex interfaces without changing waves and continuous media. the velocity model and can be extended to elastic waves and continuous media. 展开更多
关键词 ray tracing limited band ray path
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Deformation of ductile cuttings from sandstone in compaction process and experimental study of influence on porosity
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作者 GAO Bo MA Rui +2 位作者 LIU Li LIU Na WANG Yang 《Global Geology》 2015年第1期10-15,共6页
Deformation of ductile cuttings from sandstone in the mechanical compaction process was designed through the "experimental system of triaxial rock deformation",and the influence on porosity was studied by lo... Deformation of ductile cuttings from sandstone in the mechanical compaction process was designed through the "experimental system of triaxial rock deformation",and the influence on porosity was studied by looking into the deformation characteristics of ductile cuttings. The design indexes are as follows: simulated depth 0- 4 000 m,interval depth 500 m,and pressure range 0- 120 MPa at interval of 1. 5 MPa. The experimental results show that the porosity decreases as buried depth increases,indicating a negative relationship between them. The amount of compression was mainly obtained by porosity reduction and cutting deformation. Deformation of ductile cuttings is mainly ductile deformation; and deformation of crystal fragments is mainly expressed as brittle fracture,resulting in decrease of particle size. The research is of certain value for the exploration and development of oil and gas. 展开更多
关键词 ductile cuttings SANDSTONE compaction process POROSITY deformation characteristics
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The temperature dependence of optical properties of InGaN alloys 被引量:1
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作者 ZHAO ChuanZhen ZHANG Rong +7 位作者 LIU Bin FU DeYi CHEN Hui LI Ming XIE ZiLi XIU XiangQian GU ShuLin ZHENG YouDou 《Science China(Physics,Mechanics & Astronomy)》 SCIE EI CAS 2012年第3期396-399,共4页
In our experiments,the PL spectra of several In x Ga 1 x N alloy samples with In contents x=0.1,0.15 and 0.25 were measured as a function of temperature ranging from 10 K to 300 K.S-shaped temperature dependencies wer... In our experiments,the PL spectra of several In x Ga 1 x N alloy samples with In contents x=0.1,0.15 and 0.25 were measured as a function of temperature ranging from 10 K to 300 K.S-shaped temperature dependencies were observed in all InGaN samples and a sharp decrease in the full width at half maximum occurred with decreasing temperature in the moderate temperature region.It was found that both phenomena are relative to localization effects.In addition,the degree of localization effects in three samples was investigated using the band-tail model.Our findings are presented in this paper. 展开更多
关键词 INGAN PHOTOLUMINESCENCE full width at half maximum
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Boron nitride nanotube growth via boron oxide assisted chemical vapor transport-deposition process using LiNO3 as a promoter 被引量:2
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作者 Andrei T. Matveev Konstantin L. Firestein +4 位作者 Alexander E. Steinman Andrey M. Kovalskii Oleg I. Lebedev Dmitry V. Shtansky Dmitri Golberg 《Nano Research》 SCIE EI CAS CSCD 2015年第6期2063-2072,共10页
High-purity straight and discrete multiwalled boron nitride nanotubes (BNNTs) were grown via a boron oxide vapor reaction with ammonia using LiNO3 as a promoter. Only a trace amount of boron oxide was detected as an... High-purity straight and discrete multiwalled boron nitride nanotubes (BNNTs) were grown via a boron oxide vapor reaction with ammonia using LiNO3 as a promoter. Only a trace amount of boron oxide was detected as an impurity in the BNNTs by energy-dispersive X-ray (EDX) and Raman spectroscopies. Boron oxide vapor was generated from a mixture of B, FeO, and MgO powders heated to 1,150 ℃, and it was transported to the reaction zone by flowing ammonia. Lithium nitrate was applied to the upper side of a BN bar from a water solution. The bar was placed along a temperature gradient zone in a horizontal tubular furnace. BNNTs with average diameters of 30-50 nm were mostly observed in a temperature range of 1,280-1,320 ℃. At higher temperatures, curled polycrystalline BN fibers appeared. Above 1,320 ℃, the number of BNNTs drastically decreased, whereas the quantity and diameter of the fibers increased. The mechanism of BNNT and fiber growth is proposed and discussed. 展开更多
关键词 boron nit-ride nanotubes CVD lithium nitrate lithium borate BNNT growth mechanism
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锚定议论文写作的压舱石——略谈议论文核心概念的界定策略
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作者 林明 《高考》 2019年第1期153-154,共2页
议论文写作的第一步,应该是学会抓住作文材料中关键性词语,在真实语境下进行概念界定。如此方能锚定自己的写作方向,为主体论述的展开做好铺垫,保证逻辑的自洽性。
关键词 概念界定 范围程度 实用价值与精神价值 私域价值与公域价值
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Quality-control method for the determination of biological activity of engineered calcineurin subunit B
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作者 Xinchang Shi Huan Yang +5 位作者 Li Xu Xiang Li Zongwen Huang Yudong Han Qun Wei Chunming Rao 《Science China(Life Sciences)》 SCIE CAS CSCD 2016年第6期584-588,共5页
The aim of this study was to establish a quality-control method for calcineurin subunit B(CNB) biological activity determinations. CNB enhances the p-nitrophenylphosphate(p NPP) dephosphorylating activity of calcineur... The aim of this study was to establish a quality-control method for calcineurin subunit B(CNB) biological activity determinations. CNB enhances the p-nitrophenylphosphate(p NPP) dephosphorylating activity of calcineurin subunit A Δ316 mutant(CNAΔ316). A series of CNB concentrations were fitted to a four-parameter equation to calculate the corresponding p NPP maximum dephosphorylation rates. Values were calculated based on biological activity references using a parallel line method. The method was then validated for accuracy, precision, linearity, linear range, sensitivity, specificity, and robustness. The recovery results were greater than 98%. Intra-plate precision was 6.7%, with inter-plate precision of 10.8%. The coefficient of determination was greater than 0.98. The linear range was 0.05–50 μg m L?1, with sensitivity of 50 μg m L?1. Tested cytokines did not induce CNAΔ316 dephosphorylation of p NPP. The chosen CNAΔ316 concentration range did not affect activity determinations. 展开更多
关键词 calcineurin subunit B biological activity method establishment method validation quality control
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