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有机碱在脂肪酶Candida antarctica B催化仲醇拆分中的促进作用

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精细化工 2009年第2期26卷 157-161页

作者：吴小梅朱利民 christopher j. branford-white 夏春谷东华大学化学化工与生物工程学院上海201620 中国科学院兰州化学物理研究所羰基合成与选择氧化国家重点实验室甘肃兰州730000 伦敦都市大学健康和政策研究所英国伦敦

以离子液体[bmim]PF6为反应溶剂，乙酸乙烯酯为酰基供体，考察了脂肪酶CandidaantarcticaB催化外消旋仲醇的动力学拆分。主要考察了有机碱和无机碱对拆分反应的影响，结果发现，在反应底物中加入三乙胺或吡啶，能够极大地提高脂肪酶的... 详细信息

以离子液体[bmim]PF6为反应溶剂，乙酸乙烯酯为酰基供体，考察了脂肪酶CandidaantarcticaB催化外消旋仲醇的动力学拆分。主要考察了有机碱和无机碱对拆分反应的影响，结果发现，在反应底物中加入三乙胺或吡啶，能够极大地提高脂肪酶的活性和对映选择性，当底物邻甲氧基-α-苯乙醇和1-（2-萘基）乙醇在拆分时加入吡啶后，脂肪酶的对映选择性是未加入有机碱时的5～8倍，分别从E=65提高到E=525和从E=209提高到E=1059，因此，可高对映选择性地获得邻甲氧基--α-苯乙醇和1-（2-萘基）乙醇的手性单体。随着吡啶加入量的增加，脂肪酶的对映选择性有所下降，因此，有机碱的最佳加入量为0．01mol，原因可能是在该加入量下，脂肪酶达到了最佳pH，即处于活性构象，从而具有较高的活性和对映选择性。

关键词：离子液体脂肪酶仲醇有机碱

Apples to oranges:environmentally derived,dynamic regulation of serotonin neuron subpopulations in adulthood?

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Neural Regeneration Research 2025年第9期20卷 2596-2597页

作者： christopher j.O’Connell Matthew j.Robson Department of Genetics College of MedicineHarvard UniversityBostonMAUSA j.mes L.Winkle College of Pharmacy Division of Pharmaceutical SciencesUniversity of CincinnatiCincinnatiOHUSA Neuroscience Graduate Program College of MedicineUniversity of CincinnatiCincinnatiOHUSA

Traumatic brain inj.ry(TBI)is a public health problem with an undue economic burden that impacts nearly every age,ethnic,and gender group across the globe(Capizzi et al.,2020).TBIs are often sustained during a dynamic range of exposures to energetic environmental forces and as such outcomes are typically heterogeneous regarding severity and pathology(Capizzi et al.,2020).

关键词： sustained orange dynamic

芳香/脂肪族共聚脲多孔膜的微观形态及其性能的初步研究

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膜科学与技术 2010年第1期30卷 44-49页

作者：李雪莲朱利民 branford-white christopher 陈大俊东华大学材料科学与工程学院纤维材料改性国家重点实验室化学化工与生物工程学院生物工程系上海201620 伦敦都市大学卫生研究与政策研究所伦敦N78DB

在相同制膜条件下,采用扩散致相转化法制备了芳香/脂肪族共聚脲多孔膜.通过对孔隙率、力学性能的测试及扫描电镜的微观分析,讨论了凝胶浴体系中溶剂的体积百分数及同类制膜大分子的不同链段结构对膜微观结构和机械性能的影响.实验结果表... 详细信息

在相同制膜条件下,采用扩散致相转化法制备了芳香/脂肪族共聚脲多孔膜.通过对孔隙率、力学性能的测试及扫描电镜的微观分析,讨论了凝胶浴体系中溶剂的体积百分数及同类制膜大分子的不同链段结构对膜微观结构和机械性能的影响.实验结果表明:随着凝固浴中溶剂体积百分含量的增加,多孔膜表面的微孔直径逐渐增大;而相应截面的指状孔有缩小的趋势,直到最终消失而形成完全海绵状孔的截面形态;制膜大分子本身的结构对膜形态结构及性能有重大影响:三种共聚脲多孔膜都具有非对称结构,不同结构的共聚脲制备出的多孔膜各自的表面、截面形态都不相同;多孔膜的机械性能也都各不相同,其中芳香族共聚脲多孔膜具有最好的机械性能.

关键词：芳香/月旨肪族共聚脲多孔膜膜形态膜性能

Himalayan Tectonics:Preface

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Geoscience Frontiers 2019年第3期10卷 791-792页

作者： Kyle Larson christopher j. Spencer Tectonics and Geodynamics Earth Environmental and Geographical Sciences IKBSAS University of British Columbia Earth Dynamics Research Group The Institute for Geoscience Research (TIGeR) Department of Applied Geology Curtin University

The Himalayan-Tibetan orogen system serves as the modern paradigm for understanding convergence-related processes in orogenic belts. The advancements made studying the region have been applied to other ancient orogenic belts leading not only to a better understanding of their development, but also of secular changes in collisional processes. As more advanced methodologies are introduced and utilized in geological research, the type, scale, and quality of data available enable quantification of geological processes not previously possible. These complex and robust datasets now form the core of many of the research proj.cts undertaken across the Himalaya and continue to provide unprecedented insight into the myriad different aspects of the evolution of the collisional system.

关键词： Himalayan-Tibetan system evolution

Studying turbulence structure near the wall in hydrodynamic flows:An approach based on the Schur decomposition of the velocity gradient tensor

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j.urnal of Hydrodynamics 2022年第5期34卷 806-825页

作者： christopher j.Keylock School of Architecture Building and Civil EngineeringLoughborough UniversityLeicestershireUK

The Schur decomposition of the velocity gradient tensor(VGT)is an alternative to the classical Cauchy-Stokes decomposition into rotation rate and strain rate ***,there have been several strands of work that have employed this decomposition to examine the physics of turbulence dynamics,including approaches that combine the Schur and Cauchy-Stokes *** are briefly reviewed before the latter approach is set *** partitions the rotation rate and strain rate tensors into normal/local and non-normal/non-local *** then study the relation between the VGT dynamics and ej.ction-sweep events in a channel flow *** show that the sweeps in particular exhibit novel behaviour compared with either the other quadrants,or the flow in general,with a much-reduced contribution to the dynamics from the non-normal terms above the viscous *** particular,the reduction in the production term that is the interaction between the non-normality and the normal straining reduces in the log-layer as a consequence of an absence of alignment between the non-normal vorticity and the strain rate *** have been early forays into using the Schur transform approach for subgrid-scale modelling in large-eddy simulation(LES)and this would appear to be an exciting way forward.

关键词： Turbulence channel flow velocity gradient tensor Schur decomposition

Synthesis and Bioassay of 4-Substituted 2-Oxoglutaric Acids

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Chinese Chemical Letters 2006年第2期17卷 156-158页

作者： Qiu Yun CHEN Qing Shan LIU christopher j. SCHOFIELD Department of Chemistry Huangshan University Tunxi 245021 Department of Chemistry University of Oxford South Park Road Oxford OX1 3TA UK

Three 2-oxoglutaric acid analogues were synthesized. Their interaction with factor- inhibiting hypoxia-inducible factor （FIH） was studied using LC-MS method. The results show that hydrophobic substitutes of 2-oxoglu... 详细信息

关键词： 2-Oxoglutatic acid analogues inhibitor.

Development process for a higher capacity Propsetter~ system

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International j.urnal of Mining Science and Technology 2018年第1期28卷 121-126页

作者： christopher j.Brown Product Development-Strata Worldwide LLC

As longwall tailgate support technologies continue to be developed and improved, strata worldwide has worked to design and manufacture a revised Propsetter to provide additional support capacity and enable applications at greater mine *** support is targeted for tailgate applications, however, it can also be utilized for roof support in various types of mining *** paper describes the design changes for enhancing the support capacity of the Propsetter to more closely align its performance with other support technologies currently being employed in longwall *** changes to each design aspect of the Propsetter was key to successfully improving the roof support's load capacity while maintaining controlled *** the load capacity would allow a mine to improve support efficiency with a smaller, less intrusive support compared to support alternatives and reduce the cost per foot of supported *** target support capacity was 711–890 k N at 50 mm of deformation to more closely match the performance of competing tailgate supports such as the 610 mm-diameter CAN~.To achieve this goal, changes were made to all design aspects of the Propsetter: diameter, wedge cut depth and angle, pod size, and confinement *** results from the NIOSH Mine Roof Simulator verified that these design changes were successful in increasing the capacity of the Propsetter to the 711–890 k N range at fifty mms of deformation.

关键词： Propsetter Can Longwall mining Tailgate roof support Controlled deformation

Plasma-catalysis: Is it j.st a question of scale?

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Frontiers of Chemical Science and Engineering 2019年第2期13卷 264-273页

作者： j.christopher whitehead School of Chemistry The University of ManchesterManchester M13 9PLUK

The issues of describing and understanding the changes in performance that result when a catalyst is placed into plasma are discussed. The different chemical and physical interactions that result and how their combination might produce beneficial results for the plasma-catalytic processing of different gas streams are outlined with particular emphasis being placed on the different range of spatial and temporal scales that must be considered both in experiment and modelling. The focus is on non-thermal plasma where the lack of thermal equilibrium creates a range of temperature scales that must be considered. This contributes in part to a wide range of inhomogeneity in different properties such as species concentrations and electric fields that must be determined experimentally by in situ methods and be incorporated into modelling. It is concluded that plasmacatalysis is best regarded as conventional catalysis perturbed by the presence of a discharge, which modifies its operating conditions, properties and outcomes often in a very localised way. The sometimes used description "plasma-activated catalysis" is an apt one.

关键词： plasma catalysis plasma-activated catalysis non-thermal plasma CO2 conversion

Expression of octopaminergic receptor genes in 4 nonneural tissues in female Nicrophorus vespilloides beetles

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Insect Science 2015年第4期22卷 495-502页

作者： christopher B. Cunningham Mary K. Douthit Allen j. Moore Department of Genetics University of Georgia Athens GA 30602 USA

Octopamine regulates the function of many tissues and physiological processes in invertebrates. The expression of octopamine receptor genes has been examined in multiple tissue types in several different insect orders. However, little work has addressed this issue in Coleoptera. Most studies characterize individual genes in different tissue types, but here we describe the expression of 6 octopamine receptor genes in thoracic musculature, oviducts, Malpighian tubules, and fat body of female Nicrophorus vespilloides beetles to characterize both different genes and different tissues within a single study. We then compare the gene expression profiles found in this beetle to other insects to examine the extent to which expression profiles are conserved across insects. We also examine the relative involvement of octopamine verses octopamine/tyramine receptors based on receptor gene expression in each tissue to help elucidate if tyramine plays a role in the regulation of these tissues. We find a high degree of overlap in the expression profile of the 6 genes examined in the thoracic muscula^tre, a moderate amount for the oviducts, and divergent profiles for Malpighian tubules and fat body. Based on expression difference in receptor subtypes, our results also support the suggestion that tyramine is a biogenic amine with physiological actions separate from octopamine.

关键词： biogenic amines Coleoptera G-protein coupled receptors quantitative real-time PCR