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用生物反应器生产L-氨基酸

中国生物工程杂志 1986年第4期 33-38页

作者： b. K. hamilton ,梅芳

现已有几种L-氨基酸是用生物反应器中的酶或全细胞生产的。最早采用这种技术的例子之一是日本L-天冬氨酸的生产。最近放大了由肉桂酸和氨生产L-苯丙氨酸的生物反应器法,产物效价达60克/升以上,原料转化率约为90%。为由甘氨酸和甲醛生产

关键词：生物反应器甲醛全细胞效价脂肪族醛滴度氨基酸氨基羧酸 SHMT

Colorful facial markings are associated with foraging rates and affiliative relationships in a wild group-living cichlid fish

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Current Zoology 2024年第1期70卷 70-78页

作者： b.ett M.Culb.rt James b.b.rnett Isaac Y.Ligocki Matthew G.Salena Marian Y.L.Wong Ian M.hamilton Sigal b.lshine Department of Integrative b.ology University of GuelphGuelphOntarioCanada Department of Psychology Neuroscience&BehaviourMcMaster UniversityHamiltonOntarioCanada Department of Evolution Ecologyand Organismal BiologyThe Ohio State UniversityColumbusOHUSA Department of b.ology Millersville UniversityMillersvillePAUSA School of Earth Atmospheric and Life SciencesUniversity of WollongongWollongongNew South WalesAustralia Department of Mathematics The Ohio State UniversityColumbusOHUSA

Many animals use color to signal their quality and/or b.havioral *** signals have b.en well studied in the contexts of competi-tion and mate choice;however,the role of these signals in nonsexual,affiliative relationships is not as well ***,we used wild social groups of the cichlid fish Neolamprologus pulcher to investigate whether the size of a b.ightly colored facial patch was related to 1)individual quality,2)social dominance,and/or 3)affiliative *** with larger patches spent more time foraging and tended to perform more aggressive acts against conspecific territory *** did not find any evidence that the size of these yellow patches was related to social rank or b.dy size,b.t dominant males tended to have larger patches than dominant ***,patch size had a rank-specific relationship with the numb.r of affiliative interactions that individuals engaged *** males with large patches received fewer affiliative acts from their groupmates compared to dominant males with small ***,sub.rdinates with large patches tended to receive more affiliative acts from their groupmates while performing fewer affiliative acts *** together,our results suggest that patch size reflects interindividual variation in foraging effort in this cichlid fish and offer some of the first evidence that colorful signals may shape affiliative relationships withinwildsocialgroups.

关键词： affiliation foraging Lake Tanganyika Neolamprologus pulcher visual signals

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砷化镓中深能级的光谱研究

红外研究 1984年第4期 272-272页

作者：葛惟锟 b.hamilton 中国科学院半导体研究所英国曼彻斯特大学理工学院

目前半导体中深能级探测的实验技术大致可以分为三类,即结电容技术、光谱技术和电子顺磁共振技术。本文介绍用光谱技术对N型砷化镓中若干深能级所做的研究,包括光荧光、阴极荧光与阴极荧光瞬态的测量,以及对深中心的能级、起源和电子-... 详细信息

目前半导体中深能级探测的实验技术大致可以分为三类,即结电容技术、光谱技术和电子顺磁共振技术。本文介绍用光谱技术对N型砷化镓中若干深能级所做的研究,包括光荧光、阴极荧光与阴极荧光瞬态的测量,以及对深中心的能级、起源和电子-声子耦合等的初步分析。采用两种样品:在N型GaAs衬底上用MOCVD外延的N型GaAs(掺S)的样品和

关键词：阴极荧光深能级电子能态光谱技术

A Historical Perspective on Development of Systems Engineering Discipline:A Review and Analysis

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Journal of Systems Science and Systems Engineering 2020年第1期29卷 1-35页

作者： Niamat Ullah Ib.e Hossain Raed M.Jaradat Michael A.hamilton Charles b.Keating Simon R.Goerger Department of Industrial and Systems Engineering Mississippi State UniversityPO Box 9542Mississippi State 39762USA Department of Industrial and Systems Engineering Mississippi State UniversityPO Box 9542Mississippi State39762USA Institute for Systems Engineering Research(ISER) Mississippi State University 3909 Halls Ferry RdVicksburgMS 39180 Department of Engineering Management&Systems Engineering Old Dominion UniversityNorfolkVA 23529 eInstitute for Systems Engineering Research(ISER) U.S Army Engineer Research Development Center(ERDC)3909 Halls Ferry RdVicksburgMS 39180

Since its inception,Systems Engineering(SE)has developed as a distinctive discipline,and there has b.en significant progress in this field in the past two *** to other engineering disciplines,SE is not affirmed b. a set of underlying fundamental propositions,instead it has emerged as a set of b.st practices to deal with intricacies stemming from the stochastic nature of engineering complex systems and addressing their *** the existing methodologies and paradigms(dominant patterns of thought and concepts)of SE are very diverse and somewhat *** appears to create some confusion regarding the design,deployment,operation,and application of *** purpose of this paper is 1)to delineate the development of SE from 1926-2017 b.sed on insights derived from a histogram analysis,2)to discuss the different paradigms and school of thoughts related to SE,3)to derive a set of fundamental attrib.tes of SE using advanced coding techniques and analysis,and 4)to present a newly developed instrument that could assess the performance of systems *** than Two hundred and fifty different sources have b.en reviewed in this research in order to demonstrate the development trajectory of the SE discipline b.sed on the frequency of pub.ication.

关键词： Systems Engineering(SE) history development systems engineering attrib.tes performance measures

Structure and function of epididymal protein cysteine-rich secretory protein-1

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Asian Journal of Andrology 2007年第4期9卷 508-514页

作者： Kenneth P. Rob.rts Daniel S. Johnston Michael A. Nolan Joseph L. Wooters Nicole C. Waxmonsky Laura b. Piehl Kathy M. Ensrud-b.wlin David W. hamilton Department of Urologic Surgery Cell Biology and Development University of Minnesota Minneapolis MN 55455 Contraception Women＇s Health ＆ Musculoskeletal Biology Woman＇s Health Research Institute Wyeth Research Collegeville PA 19426 USA Inflammation Department Molecular Profiling and Biomarker Discovery Wyeth Research Cambridge MA 02140 USA b.ological Technologies Molecular Profiling and Biomarker Discovery Wyeth Research Cambridge MA 02140 USA Department of Genetics Cell Biology and Development University of Minnesota Minneapolis MN 55455 USA

Cysteine-rich secretory protein-1 （CRISP-1） is a glycoprotein secreted b. the epididymal epithelium. It is a memb.r of a large family of proteins characterized b. two conserved domains and a set of 16 conserved cysteine residues. In mammals, CRISP-1 inhib.ts sperm-egg fusion and can suppress sperm capacitation. The molecular mechanism of action of the mammalian CRISP proteins remains unknown, b.t certain non-mammalian CRISP proteins can b.ock ion channels. In the rat, CRISP-1 comprises two forms referred to as Proteins D and E. Recent work in our lab.ratory demonstrates that the D form of CRISP-1 associates transiently with the sperm surface, whereas the E form b.nds tightly. When the spermatozoa are washed, the E form of CRISP-1 persists on the sperm surface after all D form has dissociated. Cross-linking studies demonstrate different protein-protein interaction patterns for D and E, although no b.nding partners for either protein have yet b.en identified. Mass spectrometric analyses revealed a potential post-translational modification on the E form that is not present on the D form. This is the only discernab.e difference b.tween Proteins D and E, and presumab.y is responsib.e for the difference in b.havior of these two forms of rat CRISP- 1. These studies demonstrate that the more ab.ndant D form interacts with spermatozoa transiently, possib.y with a specific receptor on the sperm surface, consistent with a capacitation-suppressing function during sperm transit and storage in the epididymis, and also confirm a tightly b.und population of the E form that could act in the female reproductive tract. （Asian J Androl 2007 July; 9： 508-514）

关键词： cysteine-rich secretory protein-1 epididymis sperm capacitation

三峡水库春季营养盐和浮游植物空间分布及其影响机制

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环境科学研究 2015年第7期28卷 1069-1077页

作者：张磊夏志强周伟 hamilton Paul b.HAFFNER Douglas 西南大学资源环境学院重庆400715 重庆市国际科技合作示范基地中加三峡水域科学研究中心重庆400715 长江流域水资源保护局长江流域水环境监测中心湖北武汉430010 加拿大国家自然博物馆加拿大渥太华K1P6P4 加拿大温莎大学大湖环境研究中心加拿大安大略温莎N9B3P4

为研究三峡水库春季水体营养盐与浮游植物的空间分布状况,于2013年3月对三峡水库22条支流及干流的6个断面进行采样监测.结果表明:来水、回水、河口和干流4类断面ρ(TN)平均值分别为1.69、1.84、2.01、1.51 mg/L;ρ(TP)平均值分别为0.115... 详细信息

为研究三峡水库春季水体营养盐与浮游植物的空间分布状况,于2013年3月对三峡水库22条支流及干流的6个断面进行采样监测.结果表明:来水、回水、河口和干流4类断面ρ(TN)平均值分别为1.69、1.84、2.01、1.51 mg/L;ρ(TP)平均值分别为0.115、0.191、0.179和0.181 mg/L;不同类型断面间ρ(TN)、ρ(TP)差异不显著;水体中N、P的主要形态分别为NO3--N和PO43--P;N/P〔n(N)/n(P)〕从来水(110.8)至干流(18.9)逐渐降低.三峡水库总体上为中营养状态,回水和河口区富营养化程度较高,富营养断面比例分别为45.4%和36.4%.研究期间共检出浮游植物8门98属,其中以绿藻门、硅藻门和蓝藻门为主,分别检出42、26和17属;从组成上看,来水和干流断面以硅藻-绿藻为主,回水、河口断面以绿藻-硅藻为主.浮游植物丰度由高到低依次为回水、河口、来水和干流断面.调查期间,22条支流中有15条支流在不同位置发生水华,但主要集中在回水区;拟多甲藻水华为主要类型且集中在库区的下游支流,而库区中上游支流则以隐藻、衣藻、小球藻、小环藻等水华为主.环境因子排序分析表明,在水华集中的回水-河口区域,影响浮游植物丰度分布的主要环境因子数明显少于其他区域,温度和ρ(DO)为该区域浮游植物丰度分布的主要影响因子,而ρ(TN)、ρ(TP)的影响不明显.

关键词：三峡水库水华春季回水空间分布排序分析

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Hardening Effects in Superhard Transition-Metal b.rides

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Accounts of Materials Research 2022年第1期3卷 100-109页

作者： Lisa E.Pangilinan Shanlin Hu Spencer G.hamilton Sarah H.Tolb.rt Richard b.Kaner Department of Chemistry and b.ochemistry University of CaliforniaLos Angeles(UCLA)Los AngelesCalifornia 90095United States Department of Chemistry and b.ochemistry Department of Materials Science and Engineeringand California NanoSystems Institute(CNSI)University of CaliforniaLos Angeles(UCLA)Los AngelesCalifornia 90095United States

CONSPECTUS:Mechanical hardness is a physical property used to gauge the applications of materials in the manufacturing and machining *** of their high hardness and wear resistance,superhard materials(Vickers hardness,Hv≥40 GPa)are commonly used as cutting tools and *** diamond is the hardest known material used for industrial applications,its synthesis requires b.th high pressure and high *** in the field of superhard materials research has led to the search for alternatives with high hardness and thermal stab.lity at low *** discovery of novel ultraincompressib.e,superhard materials has largely developed through trial and error along two *** one approach,researchers comb.ne light elements,such as b.ron,carb.n,nitrogen,and oxygen,often at high pressure,to replicate the highly directional,dense,covalent b.nds of *** the second approach,these light elements(b.C,N,and O)are comb.ned with highly incompressib.e,electron-rich transition metals to form dense covalently b.nded networks at amb.ent pressure.

关键词： Transition b.ron gauge

Effects of cold and warm cross-rolling on microstructure and texture evolution of AZ31b.magnesium alloy sheet

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Journal of Magnesium and Alloys 2018年第2期6卷 121-133页

作者： Litzy Lina Choquechamb. Catorceno hamilton Ferreira Gomes de Ab.eu Angelo Fernando Padilha Department of Metallurgical and Materials Engineering Federal University of Ceará-UFCCampus do Pici-Bloco 729CEP 60440-554 FortalezaCEBrazil Department of Metallurgical and Materials Engineering Polytechnic SchoolUniversity of São Paulo-USPAv.Professor Mello de Moraes2463CEP 05508-030 São PauloSPBrazil

Mg alloys conventionally rolled often present strong b.sal textures that affect negatively further deformations,limiting their *** present research found that cross-rolling experiences in adequate conditions can weaken those intense b.sal textures as a result of the interaction of deformation mechanisms and dynamic *** effects of rolling temperature and strain rate on the microstructure and texture of an AZ31b.magnesium alloy sheet generated heterogeneous microstructure where the initial b.sal texture was strengthened during cold cross-rolling and it was gradually weakening b. the rolling reduction and the rolling temperature increases in such a way that a rather weak b.sal fib.r was produced applying reductions higher than 15%at temperatures higher than 200℃.Their ODF functions supported the texture weakening,exhib.ting a comb.nation of two crystallographic orientations represented b.{0001}and{0001}.

关键词： AZ31b.magnesium alloy Microstructure Texture Cross rolling.

Al_xGa_(1-x)As/Al_yGa_(1-y)As微腔中的激子吸收增强效应

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光子学报 1997年第10期26卷 902-906页

作者：吴惠桢吴惠桢 P.Dawson b.hamilton 杭州大学物理系杭州310028 DepartmentofPhysics UMIDTPoBox88ManchesterM601QDUK

文章采用AlxGa1-xAs／AlyGa1-yAs微腔结构，研究了微腔中激子的吸收行为，在室温下观察到了激子吸收的增强效应，激子的峰值吸收强度是自由空间中激子吸收强度的2，6倍；我们从激子与光波场相互作用和腔中模函数的分布建立了计算．激子... 详细信息

文章采用AlxGa1-xAs／AlyGa1-yAs微腔结构，研究了微腔中激子的吸收行为，在室温下观察到了激子吸收的增强效应，激子的峰值吸收强度是自由空间中激子吸收强度的2，6倍；我们从激子与光波场相互作用和腔中模函数的分布建立了计算．激子先吸收的模型，文中给出的微腔结构的数值计算表明激子的吸收增强与实验结果相一致；数值计算表明，微腔中激子吸收的强弱不仅与上、下两腔镜的反射率和腔长有关，而且还取决于量子阱在腔中的位置．

关键词：微腔微子光吸收激光器铝镓砷半导体

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