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宇航计测技术 1989年第4期8卷 66-68页

作者： b.n.taylor 张元照

随着量子化霍尔效应的发现,只要用等值的实验室电单位装置来测定四个基本常数,就可得到具有高准确度的安培、伏特和欧姆的国际单位值。通过同样的测量,也可得到其它大多数基本常数的国际单位的准确值,其中包括阿伏伽德罗常数和精细结构... 详细信息

随着量子化霍尔效应的发现,只要用等值的实验室电单位装置来测定四个基本常数,就可得到具有高准确度的安培、伏特和欧姆的国际单位值。通过同样的测量,也可得到其它大多数基本常数的国际单位的准确值,其中包括阿伏伽德罗常数和精细结构常数等。

关键词：量子化霍尔电阻国际电单位常数

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基本物理常数

物理 1990年第7期 442-447页

作者： E.R.Cohen b.n.taylor 沈乃澂

1986年的最小二乘法平差已得出了物理和化学的基本常数及转换因子的一组新的推荐值. 国际科协科技数据委员会(CODATA)最近发表了一份报告,根据二百多次不同测量结果的最小二乘法平差推导出物理化学的基本常数和转换因子的一组自洽数值.1... 详细信息

1986年的最小二乘法平差已得出了物理和化学的基本常数及转换因子的一组新的推荐值. 国际科协科技数据委员会(CODATA)最近发表了一份报告,根据二百多次不同测量结果的最小二乘法平差推导出物理化学的基本常数和转换因子的一组自洽数值.1986年的数值组代替了1973年最小二乘怯平差得出的前一组数值. 和过去几次基本物理常数的最小二乘法一样,1986年的平差数据分为两类:辅助常数和随机输入数据.辅助常数有些是定义的常数(如e和v0),它们的不确定度为零,另一些的测量值非常精密,使人们可以认为是精确的,即在与随机输入数据的不确定度比较时,它们的不确定度是很小的,因而其数值不会受最小二乘法的较大影响. 由于国际单位制(SI)电学单位的定义在实验室内是不可能复现的(例如,直径为零的无限长导体),象美国标准局那样的标准实验室,保持了为科学和工业服务的实用复现方法.保存单位与SI单位的比值,当然也必须经过实验平差,实际上也提供作为最小二乘法平差的一些输入数据. 1986年平差中的辅助常数的例子有:真空中光速c,它定义为 299 792 458 m/s 因此用秒来确定米的长度)滇空导磁率 u0,定义为 4 10-7n/A2;...

关键词：约瑟夫森频率电压系数推荐值不确定度常数数学平差

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基本常数的目前状况

国外计量 1977年第5期 46-49页

作者： b.n.taylor 沈乃澂

一、引言自从作者完成了基本常数的1973最小二乘法平差后,已为基本常数的科学技术数据委员会(CODATA)工作组和第八届 CODATA 大会相继采纳,之后又进行了一些有关的实验和理论计算。本文的目的是审查这些结果的影响,并尽可能研究第五届... 详细信息

一、引言自从作者完成了基本常数的1973最小二乘法平差后,已为基本常数的科学技术数据委员会(CODATA)工作组和第八届 CODATA 大会相继采纳,之后又进行了一些有关的实验和理论计算。本文的目的是审查这些结果的影响,并尽可能研究第五届原子质量和基本常数会议报导的最重要的新实验和计算对我们1973最小二乘法平差的推荐

关键词：基本常数兰姆位移谱线位移隐含值加权平均平差数据变化推荐值不确定度 nbS QED 不一致性法拉第

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目前实现的绝对安培是否有误?

国外计量 1977年第4期 32-34页

作者： b.n.taylor 张宝裕沈平子

一、引言实际上,电流的国际单位制(SI)单位:安培,是借助于一组稳定的惠斯顿型标准电池和标准电阻保存在国际计量局(bIPM)和各国计量标准研究所中。而被称为电流的保存单位和 SI 单位之间的关系,则是通过基于某种电流力天平形式的绝对测... 详细信息

一、引言实际上,电流的国际单位制(SI)单位:安培,是借助于一组稳定的惠斯顿型标准电池和标准电阻保存在国际计量局(bIPM)和各国计量标准研究所中。而被称为电流的保存单位和 SI 单位之间的关系,则是通过基于某种电流力天平形式的绝对测量建立起来的。另一方面,这个关系也可通过适当地

关键词：加权平均值 SI 标准电池电阻广义算术平均值电压标准电阻抗方程保存单位基本常数平差原子质量质量(物理) nbS 电学量单位基准器电流天平安培天平推荐值直接测量

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基本物理常数及能量转换因子

中国检验检测 1980年第3期 1-3页

作者： E.R.Cohen b.n.taylor 本刊编辑部

本表给出的值是由 E.R.Cohen 和 b.n.taylor 用最小二乘法评定选择出来的。这项工作是在科学技术数据委员会基本常数工作组的主持下进行的,并由科学技术数据委员会(CODATA)正式采用。[J.Phys.Chem.Ref.

关键词：基本物理常数能量转换因子原子质量单位静止质量质量(物理) 特斯拉焦耳静电单位电子电荷

基本物理常数最近用最小二乘调整得出了一组新的基本常数和物理、化学转换因数的推荐值。

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世界地震译丛 2002年第3期33卷 73-83页

作者： P．J．Mohr b.n.taylor 李国荣吕春来陈运泰不详中国地震局地球物理研究所

科学技术数据委员会(CODATA)作为国际科学理事会(ICSU，前国际科学联合会理事会)的跨学科委员会。成立于1966年。之后不久，即1969年，科学技术数据委员会成立了基本常数工作组。

关键词：最小二乘里德伯常数牛顿万有引力常数推荐值结构常数普朗克常数

blockade of Rho-associated kinase prevents inhibition of axon regeneration of peripheral nerves induced by anti-ganglioside antibodies

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neural Regeneration Research 2024年第4期19卷 895-899页

作者： Andrés berardo Cristian R.bacaglio bárbara b.báez Rubén Sambuelli Kazim A.Sheikh Pablo H.H.Lopez Laboratorio de neurobiología Instituto de Investigación Médica Mercedes y Martin Ferreyra(INIMEC)-Consejo Nacional de Investigaciones Cientificas y Técnicas(CONICET)Universidad Nacional de Córdoba Departamento de Química biológica-Centro de Investigaciones en Química biológica de Córdoba(CIQUIbIC)-Consejo nacional de Investigaciones Cientificas y Técnicas(COnICET) Facultad de Cs.QuímicasUniversidad Nacional de Córdoba Servicio de Anatomía Patológica Clínica Universitaria Reina FabiolaUniversidad Católica de Córdoba Department of neurology University of Texas Medical School at Houston

Anti-ganglioside antibodies are associated with delayed/poor clinical recovery in Guillain-barrèsyndrome,mostly related to halted axon regeneration.Cross-linking of cell surface gangliosides by anti-ganglioside antibodies triggers inhibition of nerve repair in in vitro and in vivo paradigms of axon regeneration.These effects involve the activation of the small GTPase Rho A/ROCK signaling pathways,which negatively modulate growth cone cytoskeleton,similarly to well stablished inhibitors of axon regeneration described so far.The aim of this work was to perform a proof of concept study to demonstrate the effectiveness of Y-27632,a selective pharmacological inhibitor of ROCK,in a mouse model of axon regeneration of peripheral nerves,where the passive immunization with a monoclonal antibody targeting gangliosides GD1a and GT1b was previously reported to exert a potent inhibitory effect on regeneration of both myelinated and unmyelinated fibers.Our results demonstrate a differential sensitivity of myelinated and unmyelinated axons to the pro-regenerative effect of Y-27632.Treatment with a total dosage of 9 mg/kg of Y-27632 resulted in a complete prevention of anti-GD1a/GT1b monoclonal antibody-mediated inhibition of axon regeneration of unmyelinated fibers to skin and the functional recovery of mechanical cutaneous sensitivity.In contrast,the same dose showed toxic effects on the regeneration of myelinated fibers.Interestingly,scale down of the dosage of Y-27632 to 5 mg/kg resulted in a significant although not complete recovery of regenerated myelinated axons exposed to anti-GD1a/GT1b monoclonal antibody in the absence of toxicity in animals exposed to only Y-27632.Overall,these findings confirm the in vivo participation of Rho A/ROCK signaling pathways in the molecular mechanisms associated with the inhibition of axon regeneration induced by anti-GD1a/GT1b monoclonal antibody.Our findings open the possibility of therapeutic pharmacological intervention targeting Rho A/Rock pathway in immune neuropathies associated wi

关键词： anti-ganglioside antibodies anti-glycan antibodies axon regeneration ganglioside Guillain-barrésyndrome nerve repair ROCK Y-27632

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Genes & Diseases 2024年第3期11卷 66-68页

作者： Aswathi n Jincy M.Jose Sreelata b.nair Prabha S.n Pappachan S Department of Medical Genetics Lifeline Super Specialty HospitalPathanamthittaKerala 691523India Lifeline Super Specialty Hospital PathanamthittaKerala 691523India

Alagille syndrome(ALGS;OMIM#118450)is a highlyvariable,multi-systemic,autosomal dominant disorder,caused by mutations in the Jagged Canonical notch Ligand 1(JAG1)gene(20p12.2)or in the neurogenic locus notch homolog protein 2(nOTCH2)gene(1p13).^(1)It primarily affects the liver,heart,eyes,face,kidney,skin,vertebrae,and skeleton.^(1,2)The JAG1 gene has 26 exons and about 90%of the ALGS cases result from pathogenic variants in the JAG1 and around 7%of cases have deletions in chromosome 20 that include this gene.

关键词： JAG1 cases notch

Astrophysical S-factor and reaction rate for 15n(p,γ)16O within the modified potential cluster model

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Chinese Physics C 2024年第4期48卷 130-145页

作者： S.b.Dubovichenko A.S.Tkachenko R.Ya.Kezerashvili n.A.burkova b.M.Yeleusheva Fesenkov Astrophysical Institute 050020 AlmatyKazakhstan new York City College of Technology City University of New YorkBrooklyn11201 New YorkUSA Graduate School and University Center City University of New York10016 New YorkUSA al-Farabi Kazakh national University 050040 AlmatyKazakhstan

We study radiative p^(15)n capture on the ground state of ^(16)O at stellar energies within the framework of a modified potential cluster model(MPCM)with forbidden states,including low-lying resonances.The investigation of the ^(15)n(p,γ0)^(16)O reaction includes the consideration of ^(3)S_(1) resonances due to E1 transitions and the contribution of the ^(3)P_(1) scattering wave in the p+^(15)n channel due to the ^(3)P_(1)→^(3)P_(0)M1 transition.We calculated the astrophysical low-energy S-factor,and the extrapolated S(0)turned out to be within 34.7−40.4 keV·b.The important role of the asymptotic constant(AC)for the ^(15)n(p,γ0)16O process with interfering ^(3)S_(1)(312)and ^(3)S_(1)(962)resonances is elucidated.A comparison of our calculation for the S-factor with existing experimental and theoretical data is addressed,and a reasonable agreement is found.The reaction rate is calculated and compared with the existing rates.It has negligible dependence on the variation of AC but shows a strong impact of the interference of ^(3)S_(1)(312)and ^(3)S_(1)(962)resonances in reference to the CnO Gamow windows,especially at low temperatures.We estimate the contribution of cascade transitions to the reaction rate based on the exclusive experimental data from Phys.Rev.C.85,065810(2012).The reaction rate enhancement due to the cascade transitions is observed from T_(9)>0.3 and reaches the maximum factor~1.3 at T_(9)=1.3.We present the Gamow energy window and a comparison of rates for radiative proton capture reactions ^(12)n(p,γ)^(13)O,^(13)n(p,γ)^(14)O,^(14)n(p,γ)^(15)O,and ^(15)n(p,γ)^(16)O obtained in the framework of the MPCM and provide the temperature windows,prevalence,and significance of each process.

关键词： low and astrophysical energies p^(15)n system thermonuclear reaction rate potential cluster model CnO-cycle

Direct microwave leaching conditions of rare earth elements in fluorescent wastes

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Journal of Rare Earths 2024年第6期42卷 1165-1174,I0007页

作者： A.bilen b.birol M.n.Saridede S.S.Kaplan M.S.Sonmez Department of Metallurgical and Materials Engineering Yildiz Technical UniversityIstanbulTurkey Department of Chemical Engineering and Materials Science Stevens Institute of TechnologyNew JereyUSA Department of Metallurgical and Materials Engineering Istanbul Technical UniversityIstanbulTurkey

The luminescent phosphor powder in the fluorescent lamp constitutes 2%of the lamp’s weight.It can be mentioned that fluorescent wastes are a crucial raw material to produce rare earth oxides.In the present study,microwave leaching process was conducted to dissolve rare earth elements yttrium(Y),europium(Eu),and remaining rare earth elements(REEs)present in the phosphor powder of the fluorescent lamp.and the yields were compared.In the microwave leaching process,the effects of the temperature(80-160℃),acid type(hydrochloric acid(HCl),nitric acid(HnO_(3)),sulphuric acid(H_(2)SO_(4))),acid concentration(0.5-6 mol/L),solid to liquid ratio(0.1:10-0.5:10)and reaction time(5-90 min)parameters on leaching efficiencies of varying rare earth elements and calcium were investigated.The highest yield was obtained in the direct microwave leaching of fluorescent waste with the experimental conditions of 6 mol/L HCl,160℃,0.1:10 solid-to-liquid ratio(S:L),and 90 min.Activation energy calculations were made,and kinetic models of the reactions were obtained,and it is observed that Y and Eu dissolution is diffusion-controlled,on the other hand,lanthanum(La),cerium(Ce),and terbium(Tb)were examined to be chemical reaction controlled.Moreover,calcium(Ca)and gadolinium(Gd)seem coherent with the mixed model.Concurrently,mathematical models of all experimental studies are created with the response surface box-behnken method and the correlation coefficients of all the models are over 90%.

关键词： Rare earth elements(REEs) Direct microwave leaching Fluorescent waste Kinetic models Response surface method