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Effect of reduction pretreatment on the structure and catalytic performance of Ir-In_(2.O_(3)catalysts for CO_(2. hydrogenation to methanol

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Journal of Environmental sciences 2024年第6期140卷 2-11页

作者： Changyu Ding Feifei yang Xue Ye Chongya yang Xiaoyan Liu Yuanlong Tan Zheng Shen Hongmin Duan Xiong Su Yanqiang {2. CAS Key Laboratory of Science and Technology on applied Catalysis Dalian Institute of Chemical PhysicsChinese Academy of SciencesDalian 116023China University of chinese Academy of {1. Beijing 100049China

In_(2.O_(3)has been found a promising application in CO_(2.hydrogenation to methanol,which is beneficial to the utilization of CO_(2..The oxygen vacancy(O_(v))site is identified as the catalytic active center of this ***,there remains a great challenge to understand the relations between the state of oxygen species in In_(2.O_(3)and the catalytic performance for CO_(2.hydrogenation to *** the present work,we compare the properties of multiple In_(2.O_(3)and Ir-promoted In_(2.O_(3)(Ir-In_(2.O_(3))catalysts with different Ir loadings and after being pretreated under different reduction *** CO_(2.conversion rate of Ir-In_(2.O_(3)is more promoted than that of pure In_(2.O_(3).With only a small amount of Ir loading,the highly dispersed Ir species on In_(2.O_(3)increase the concentration of O_(v)sites and enhance the *** finely tuning the catalyst structure,Ir-In_(2.O_(3)with an Ir loading of 0.1. wt.%and pre-reduction treatment under 300℃exhibits the highest methanol yield of 1.6 mgCH_(3)OH/(gcat·hr).Characterizations of Raman,electron paramagnetic resonance,X-ray photoelectron spectroscopy,CO_(2.-temperature programmed desorption and CO_(2.-pulse adsorption for the catalysts confirm that more O_(v)sites can be generated under higher reduction temperature,which will induce a facile CO_(2.adsorption and desorption *** performance for methanol production requires an adequate dynamic balance among the surface oxygen atoms and vacancies,which guides us to find more suitable conditions for catalyst pretreatment and reaction.

关键词： Carbon dioxide Hydrogenation Methanol In_(2.O_(3) Fixed-bed Reduction temperature

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Dynamical Evolution of Gamma-Ray Burst Remnants with Evolving Radiative Efficiency

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chinese Journal of Astronomy and Astrophysics 2002年第6期2卷 525-532页

作者： Jin-Bo Feng, Yong-Feng huang, Zi-Gao Dai and Tan Lu1.Department of Astronomy, Nanjing University, Nanjing 2.1}0932.LCRHEA, {1. for High-Energy Physics, chinese Academy of sciences, beijing 1.0039 LCRHEA Institute for High-Energy Physics Chinese Academy of Sciences Beijing 100039

In previous works, a generic dynamical model has been suggested by huang. et al., which is shown to be correct for both adiabatic and radiative blast-waves, in both ultra-relativistic and non-relativistic phases. In deriving their equations, huang et al. have assumed that the radiative efficiency of the fireball is constant. They then {2. their model directly to realistic cases where the radiative efficiency evolves with time. In this paper, we abandon the above assumption and re-derive a more accurate dynamical equation for gamma-ray burst remnants. Numerical results show that the model presented by huang et al. is accurate enough in general cases.

关键词： gamma rays : bursts hydrodynamics radiation mechanisms : nonthermal

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靶区大气环境对再入体落点精度影响仿真研究

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系统仿真学报 2009年第13期21卷 3910-3913页

作者：黄华徐幼平邓志武北京应用气象研究所北京100029 解放军理工大学气象学院南京211101

利用美国Cape Canaveral靶场近十年气象观测统计资料,建立靶区大气环境逐月蒙特卡洛样本集,在其基础上,利用Matlab/Simulink/RTW仿真工具,针对欧洲EXPERT/REV再入体,建立非线性六自由度飞行仿真模型,并对其落点参数进行了逐月蒙特卡洛... 详细信息

利用美国Cape Canaveral靶场近十年气象观测统计资料,建立靶区大气环境逐月蒙特卡洛样本集,在其基础上,利用Matlab/Simulink/RTW仿真工具,针对欧洲EXPERT/REV再入体,建立非线性六自由度飞行仿真模型,并对其落点参数进行了逐月蒙特卡洛仿真研究。统计结果表明,对于弹道式再入体,Cape Canaveral靶区大气静态参数变化和风场扰动所导致的落点散布随季节有较大变化,其中风场扰动的影响起主要作用。

关键词：大气环境再入体落点精度蒙特卡洛法 Matlab/Simulink/RTW

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Identification and characterization of camptothecin tailoring enzymes in Nothapodytes tomentosa

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Journal of Integrative Plant Biology 2024年第6期66卷 1158-1169页

作者： Yin Chen Jian-Ping huang Yong-Jiang Wang Meng-Ling Tu Junheng Li Bingyan Xu Guoqing Peng Jing {1. Sheng-Xiong huang State Key Laboratory of Phytochemistry and Plant Resources in West china and Yunnan Key Laboratory of Natural Medicinal Chemistry Kunming Institute of BotanyChinese Academy of SciencesKunming 650201China University of chinese Academy of {1. Beijing 100049China Key Laboratory for Economic Plants and Biotechnology Kunming Institute of BotanyChinese Academy of SciencesKunming 650201China

Camptothecin is a complex monoterpenoid indole alkaloid with remarkable antitumor *** that two C-1. modified camptothecin derivatives,topotecan and irinotecan,have been approved as potent anticancer agents,there is a critical need for methods to access other aromatic ringfunctionalized congeners(e.g.,C-9,C-1.,etc.).However,contemporary methods for chemical oxidation are generally harsh and low-yielding when {2. to the camptothecin scaffold,thereby limiting the development of modified *** herein,we have identified four tailoring enzymes responsible for C-9 modifications of camptothecin from Nothapodytes tomentosa,via metabolomic and transcriptomic *** consist of a cytochrome P450(Nt CPT9H)which catalyzes the regioselective oxidation of camptothecin to 9-hydroxycamptothecin,as well as two methyltransferases(Nt OMT1.2.converting 9-hydroxycamptothecin to 9-methoxycamptothecin),and a uridine diphosphate-glycosyltransferase(Nt UGT5,decorating 9-hydroxycamptothecin to9-β-D-glucosyloxycamptothecin).Importantly,the critical residues that contribute to the specific catalytic activity of Nt CPT9H have been elucidated through molecular docking and mutagenesis *** work provides a genetic basis for producing camptothecin derivatives through metabolic *** will hasten the discovery of novel C-9 modified camptothecin derivatives,with profound implications for pharmaceutical manufacture.

关键词： camptothecin biosynthesis enzymatic assay Nothapodytes tomentosa tailoring enzyme transcriptomic analysis

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SYNTHESIS AND CHARACTERIZATION OF PHTHALAZINONE POLY(ARYL ETHER SULFONE KETONE)WITH CARBONYL GROUP

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chinese Journal of Polymer Science 2002年第3期20卷 225-229页

作者： Ying-nan Xuan Yan Gao Yong huang Xi-gao Jian Laboratory of Cellulose and Lignocellulosics Chemistry Guangzhou {1. of Chemistry {2. Academy of sciences, Guangzhou 51.650 china {1. of Chemistry {2. Academy of sciences, beijing 100080 china Department of Polymer Science, College of Chemical Engineering Dalian University of Technology, Dalian 1.601., china chinese Acad Sci Guangzhou Inst Chem Lab Cellulose & Lignocellulos Chem Guangzhou 510650 Peoples R China chinese Acad Sci Inst Chem Beijing 100080 Peoples R China Dalian Univ Technol Coll Chem Engn Dept Polymer Sci Dalian 116012 Peoples R China

A kind of novel heat-resistant, high performance engineering thermoplastic phthalazinone poly(aryl ether sulfone ketone) (PPESK) containing a carboxyl group in its side chain was prepared by the nucleophilic displacement reaction of 4-(4-hydroxylphenyl)- 1.(2.)-phthalazinone with di(4-chlorophenyl) sulfone, 4,4'-difluoro-benzophenone and phenolphthalin in sulfolane in the presence of K2.O3 to produce high molecular weight polymers which can be dissolved in some polar solvents such as chloroform and nitrobenzene at room temperature and can be easily cast into flexible, yellowish and transparent films. PPESK is an amorphous polymer having a decomposition temperature above 400degreesC, which indicates that it has high thermal stability. At the same time, the thermal properties of PPESKs with dicyandiamide (DICY) as curing agent indicated that the heat-resistance properties of the PPESKs are improved after curing. The apparent activation energy (A-E) of the cross-linking reaction and the reaction order (n) of PPESK/DICY were found to be 52.2.kJ/mol and ca. 1.0, respectively. Therefore, the cross-linking reaction is approximately a first order reaction.

关键词： poly(aryl ether sulfone ketone) synthesis active pendant group

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Residual strain evaluation of curved surface by grating-transferring technique and GPA

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Theoretical & applied Mechanics Letters 2011年第5期1卷 31-35页

作者： Zhanwei Liu,1.Jiangfan Zhou,1.Xianfu {2.,1.Jian Lu,{1. Huimin Xie 3,1. Department of Mechanics,School of Astronautics,beijing institute of Technology,beijing 1.0081.china 2. Department of Mechanical Engineering,The Hong Kong Polytechnic University,Hong Kong,china 3) AML,Department of Engineering Mechanics,Tsinghua University,beijing 1.0084,china AML Department of Engineering Mechanics Tsinghua University Beijing 100084 China

This paper investigates an advanced grating-transferring technique combined with geometric phase analysis (GPA) for residual strain evaluation of curved surface.A standard holographic grating is first transferred to a pre-produced epoxy resin film and then consolidated to a test region of curved *** a rubber mold and silicone rubber the deformed grating is replicated to a sheet metal after hole-drilling for release of residual *** that the grating is transferred from the sheet metal to the glass plate,which would be served as an analyzer grating (specimen grating).By GPA the local strain distributions related to the phase difference between the reference grating and analyzer grating for the released stress can be evaluated.A validation test has been conducted on the weld joint of a stainless steel tube and the obtained results demonstrate the ability of the method in measuring the residual strain of curved surface.

关键词： residual strain grating-transferring hole-drilling GPA curved surface

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Prediction and quantification of effective gas source rocks in a lacustrine basin: Western Depression in the Liaohe Subbasin, china

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Petroleum Science 2024年第4期21卷 2218-2239页

作者： Si-Bo yang Mei-Jun Li Hong Xiao Fang-Zheng Wang Guo-Gang Cai S{1.-Quan {1. State Key Laboratory of Petroleum Resources and Prospecting College of Geosciences China University of Petroleum china University of Petroleum-{1. at Karamay College of Petroleum Research institute of Petroleum Exploration and Development Liaohe Oilfield Company PetroChina

Due to limited data on the geochemical properties of natural gas, estimations are needed for the effective gas source rock in evaluating gas potential. However, the pronounced heterogeneity of mudstones in lacustrine successions complicates the prediction of the presence and geochemical characteristics of gas source rocks. In this paper, the Liaohe Subbasin of Northeast china is used as an example to construct a practical methodology for locating effective gas source rocks in typical lacustrine basins. Three types of gas source rocks, microbial, oil-type, and coal-type, were distinguished according to the different genetic types of their natural gas. A practical three-dimensional geological model was developed, refined, and {1. to determine the spatial distribution of the mudstones in the Western Depression of the Liaohe Subbasin and to describe the geochemical characteristics(the abundance, type, and maturation levels of the organic matter). Application of the model in the subbasin indicates that the sedimentary facies have led to heterogeneity in the mudstones, particularly with respect to organic matter types. The effective gas source rock model constructed for the Western Depression shows that the upper sequence(SQ2. of the Fourth member(Mbr 4) of the Eocene Shahejie Formation(Fm) and the lower and middle sequences(SQ3 and SQ4) of the Third member(Mbr 3) form the principal gas-generating interval. The total volume of effective gas source rocks is estimated to be 586 km3. The effective microbial, oil-type, and coal-type gas source rocks are primarily found in the shallow western slope, the central sags, and the eastern slope of the Western Depression, respectively. This study provides a practical approach for more accurately identifying the occurrence and geochemical characteristics of effective natural gas source rocks, enabling a precise quantitative estimation of natural gas reserves.

关键词： Effective gas source rock 3D geological modeling Spatial distribution Geochemical characteristics Lacustrine rift basin

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节杆菌BT801.因文库构建及其乙内酰脲酶基因分离与表达

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生物工程学报 2003年第3期19卷 281-285页

作者：郝淑凤张惟材袁红杰王恒梁黄留玉军事医学科学院生物工程研究所中国科学院沈阳应用生态研究所沈阳1.001.

L 乙内酰脲酶产生菌节杆菌BT80 1.染色体DNA经Sau3AI部分酶切后分离 30kb左右的片段 ,与经HpaI和PstI酶切的黏粒载体pKC5 0 5进行连接 ,将连接产物用包装蛋白包装 ,转染大肠杆菌DH5α得到 1. 0 0 0多个转化子 ,构建成节杆菌BT80 1.基... 详细信息

L 乙内酰脲酶产生菌节杆菌BT80 1.染色体DNA经Sau3AI部分酶切后分离 30kb左右的片段 ,与经HpaI和PstI酶切的黏粒载体pKC5 0 5进行连接 ,将连接产物用包装蛋白包装 ,转染大肠杆菌DH5α得到 1. 0 0 0多个转化子 ,构建成节杆菌BT80 1.基因组文库。通过薄层层析等方法筛选得到了 1.阳性克隆 ,通过亚克隆得到了乙内酰脲酶的完整基因。

关键词：乙内酰脲酶节杆菌基因文库基因表达

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大气扰动及其对无人机自动着陆影响仿真研究

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系统仿真学报 2009年第21期21卷 6821-6824页

作者：黄华陆汉城徐幼平北京应用气象研究所北京100029 解放军理工大学大气科学博士后流动站南京211101

基于流体动力学原理,建立三维非对称微下击暴流模型,同时耦合vorkarman湍流模型,对1.82.7月9日美国新奥尔良微下击暴流案例进行了仿真模拟,并与多普勒雷达资料进行了对比。在其基础上,利用Matlab/Simulink仿真工具,针对某型无人机,建... 详细信息

基于流体动力学原理,建立三维非对称微下击暴流模型,同时耦合vorkarman湍流模型,对1.82.7月9日美国新奥尔良微下击暴流案例进行了仿真模拟,并与多普勒雷达资料进行了对比。在其基础上,利用Matlab/Simulink仿真工具,针对某型无人机,建立了非线性六自由度飞行模型和自动着陆控制系统,并在大气扰动条件下,对该无人机的自动着陆过程进行了飞行仿真。仿真结果表明:所构建的微下击暴流模型简捷可靠,可有效反映真实案例的基本风场结构;作为大气扰动的主要形式,微下击暴流、湍流耦合效应对于无人机自动着陆任务的完成具有较大的影响。

关键词：微下击暴流湍流无人飞行器飞行仿真自动着陆

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Design of antiviral AGO2.dependent short hairpin RNAs

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Virologica Sinica 2024年第4期39卷 645-654页

作者： Yuanyuan Bie Jieling Zhang Jiyao Chen Yumin Zhang Muhan huang Leike Zhang Xi Zhou {1. Qiu Key Laboratory of Virology and Biosafety Wuhan Institute of VirologyChinese Academy of SciencesWuhan 430071China State Key Laboratory of Virology Wuhan Institute of VirologyChinese Academy of SciencesWuhan 430071China University of chinese Academy of {1. Beijing 100049China School of Life sciences Division of Life Sciences and MedicineUniversity of Science and Technology of ChinaHefei 230027China

The increasing emergence and re-emergence of RNA virus outbreaks underlines the urgent need to develop effective *** interference(RNAi)is a sequence-specific gene silencing mechanism that is triggered by small interfering RNAs(siRNAs)or short hairpin RNAs(shRNAs),which exhibits significant promise for antiviral ***2.dependent shRNA(agshRNA)generates a single-stranded guide RNA and presents significant advantages over traditional siRNA and *** this study,we applied a logistic regression algorithm to a previously published chemically siRNA efficacy dataset and built a machine learning-based model with high predictive *** this model,we designed siRNA sequences targeting diverse RNA viruses,including human enterovirus A71.EV71.,Zika virus(ZIKV),dengue virus 2.DENV2.,mouse hepatitis virus(MHV)and severe acute respiratory syndrome coronavirus 2.SARS-CoV-2.,and transformed them into *** validated the performance of our agshRNA design by evaluating antiviral efficacies of agshRNAs in cells infected with different *** the agshRNA targeting EV71.as an example,we showed that the anti-EV71.effect of agshRNA was more potent compared with the corresponding siRNA and ***,the antiviral effect of agshRNA is dependent on AGO2.processed guide RNA,which can load into the RNA-induced silencing complex(RISC).We also confirmed the antiviral effect of agshRNA in ***,this work develops a novel antiviral strategy that combines machine learning-based algorithm with agshRNA design to custom design antiviral agshRNAs with high efficiency.

关键词： AgshRNA Antiviral strategy Machine learning model

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