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Chinese Journal of chemistry 1993年第6期11卷 517-523页

作者： XIAO, Feng-Shou, department of chemistry, jilin {3., Changchun 13.023 department of chemistry Jilin University Changchun 130023

The reaction between [Ru_3.CO)_9(CCO)]^(2-) supported on magnesium oxide and alky- lating agent CH_3. was investigated in an attempt to understand its reactivity and mechanism by using FT-IR technique. The IR spectra show that [Ru_3.CO)_9(CCO)]^(2-)/MgO reacts with CH_3. to produce [Ru_3.CO)_9CC(O)CH_3.-/MgO, which exhibits bands at 2960, 2022, 1988, 163., 1460 and 13.0 cm^(-1). The absorption at 2960, 1460 and 13.0 cm^(-1) are attributed to -CH_3.group, while bands at 2022, 1988 and 1952 cm^(-1) are assigned to the terminal CO groups attached to ruthenium. The band at 163. cm^(-1) was assigned to acyl carbonyl. Isotopes labeled compounds CD3., ^(13.CO and [Ru_3.CO)_9(*C*CO)]^(2-) were used in investigation. The results demonstrate that β-carbon of CCO ligand is attacked by CH_3.+ species and produces [Ru_3.CO)_9CC(O)CH_3.-/MgO.

关键词： Ru CCO

Analysis and Characterization of the GABA Transaminase and Succinate Semialdehyde Dehydrogenase Genes in the Microalga Isochrysis zhanjiangensis in Response to Abiotic Stresses

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Journal of Ocean university of china 2024年第3期23卷 775-785页

作者： TIAN Jiaojiao ZHANG Lin LU Xinyue YE Lingzhi WU Yuanyuan CHEN Deshui CAO Jiayi JIANG Jiaxin XU jilin YAN Xiaojun Key Laboratory of Marine Biotechnology of Zhejiang Province School of Marine SciencesNingbo UniversityNingbo 315211China Key Laboratory of Aquacultural Biotechnology Ministry of Education Ningbo UniversityNingbo 315211China Laizhou Bay Marine Technology Co. Ltd.Yantai 261400China Fujian Dalai Seed Science and Technology Co. Ltd.Ningde 352101China

Gamma-aminobutyric acid(GABA),widely existing in different organisms,is rapidly accumulated in plants in response to environmental *** main biosynthesis and degradation pathways of GABA constitute the GABA shunt,which is tied to the tricarboxylic acid(TCA)*** transaminase(GABA-T)and succinate semialdehyde dehydrogenase(SSADH)are two essential enzymes for the GABA degradation *** there are abundant studies on GABA shunt in higher plants at the physiological and genetic levels,research on its role in microalgae remains *** study aimed at exploring the function of GABA-T and SSADH genes in Isochrysis zhanjiangensis,an important diet microalga,under different *** cloned two GABA-T genes,IzGABA-T1 and IzGABA-T2,and one SSADH gene IzSSADH from Isochrysis zhanjiangensis and conducted heterologous expression *** results showed that the overexpression of IzGABA-T1 or IzGABA-T2 enhanced the survival rates of yeast transformants under heat or NaCl stress,while the overexpression of IzSSADH improved yeast tolerance to NaCl stress but had no obvious effect on heat ***,the results of quantitative real-time polymerase chain reaction(qPCR)showed that IzGABA-T1 transcription increased in the HT(salinity 25,3.℃)and LS(salinity 15,25℃)*** 24 h,the IzGABA-T2 transcriptions increased in the HT,LS,and HS(salinity 3.,25℃)groups,but their transcription levels decreased in all groups at 48 *** transcription increased in the LS *** results suggest that IzGABA-T1,IzGABA-T2,and IzSSADH are associated with temperature and salinity stresses and possess a certain preference for different stresses.

关键词： abiotic stress GABA heterologous expression Isochrysis zhanjiangensis transcription

Kernel model-based diagnosis

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Progress in Natural Science:Materials International 2002年第2期12卷 63-67页

作者： OUYANG Dantong(department of Computer Science, jilin university, Changchun 13.012, {3.) jilin Univ Dept Comp Sci Changchun 130012 Peoples R China

The methods for computing the kernel consistency-based diagnoses and the kernel abductive diagnoses are only suited for the situation where part of the fault behavioral modes of the components are known. The characterization of the kernel model-based diagnosis based on the general causal theory is proposed, which can break through the limitation of the above methods when all behavioral modes of each component are known. Using this method, when observation subsets deduced logically are respectively assigned to the empty or the whole observation set, the kernel consistency-based diagnoses and the kernel abductive diagnoses can deal with all situations. The direct relationship between this diagnostic procedure and the prime implicants/implicates is proved, thus linking theoretical result with implementation.

关键词： model-based diagnosis general causal theory prime implicant/implicate diagnostic space.

Synthesis and Characterization of Liquid Crystal with Lower Temperature of Phase Change of meso-tetra-(4-n-lauroyloxyphenyl)porphyrin

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Chinese Chemical Letters 1999年第9期10卷 783-786页

作者： Wei LIU Tong Shun SHI(1 department of chemistry, The Forth Military Medical university, Xian 71003.2 department of chemistry, jilin university. Changchun 13.023. Fourth Mil Med Univ Dept Chem Xian 710032 Peoples R China jilin Univ Dept Chem Changchun 130023 Peoples R China

The synthesis and characterization of meso-tetra (4-n-lauroyloxy phenyl) porphyrin with long ester chains are reported. The domains of stability and the structure of the liquid crystalline phases are determined by opt... 详细信息

关键词： porphyrin liquid crystal lower temperature of phase change

Deep-reinforcement-learning-based water diversion strategy

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Environmental Science and Ecotechnology 2024年第1期17卷 68-79页

作者： Qingsong Jiang Jincheng Li Yanxin Sun jilin Huang Rui Zou Wenjing Ma Huaicheng Guo Zhiyun Wang Yong Liu State Environmental Protection Key Laboratory of All Materials Flux in River Ecosystems College of Environmental Sciences and EngineeringPeking UniversityBeijing100871PR China Rays Computational Intelligence Lab Beijing Inteliway Environmental Ltd.Beijing100085PR China Yunnan Key Laboratory of Pollution Process and Management of Plateau Lake-Watershed Yunnan Research Academy of Eco-environmental SciencesKunming650034PR Chin

Water diversion is a common strategy to enhance water quality in eutrophic lakes by increasing available water resources and accelerating nutrient *** effectiveness depends on changes in the source water and lake ***,the challenge of optimizing water diversion remains because it is difficult to simultaneously improve lake water quality and minimize the amount of diverted ***,we propose a new approach called dynamic water diversion optimization(DWDO),which combines a comprehensive water quality model with a deep reinforcement learning *** applied DWDO to a region of Lake Dianchi,the largest eutrophic freshwater lake in china and validated *** results demonstrate that DWDO significantly reduced total nitrogen and total phosphorus concentrations in the lake by 7%and 6%,respectively,compared to previous ***,annual water diversion decreased by an impressive 75%.Through interpretable machine learning,we identified the impact of meteorological indicators and the water quality of both the source water and the lake on optimal water *** found that a single input variable could either increase or decrease water diversion,depending on its specific value,while multiple factors collectively influenced real-time adjustment of water ***,using well-designed hyperparameters,DWDO proved robust under different uncertainties in model *** training time of the model is theoretically shorter than traditional simulation-optimization algorithms,highlighting its potential to support more effective decisionmaking in water quality management.

关键词： Dynamic water diversion optimization Deep reinforcement learning Process-based model Explainable decision-making Parameter uncertainty

中国政治经济学年度发展报告（2023.（下）

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政治经济学评论 2024年第3期 90+207-208页

作者： Center for Studies of Contemporary Political Economy,Research Institute for 21st-Century Marxism,Nankai university·university of Chinese Academy of Social Science Center for Teaching and Research on Capital,Renmin university of {3. National Institute of Socialist Political Economy with Chinese Characteristics,Renmin university of {3. 南开大学·中国社会科学院大学21世纪马克思主义研究院当代政治经济学研究中心中国人民大学《资本论》教学与研究中心中国人民大学全国中国特色社会主义政治经济学研究中心

编者按2023.，高质量发展扎实推进，新质生产力加快形成，我国经济总体回升向好，圆满实现发展主要预期目标。为针对性地破解经济恢复发展中的难题，聚焦推进中国式现代化进程中的重点、难点问题，中国政治经济学界开展系统深入研究，...

编者按2023.，高质量发展扎实推进，新质生产力加快形成，我国经济总体回升向好，圆满实现发展主要预期目标。为针对性地破解经济恢复发展中的难题，聚焦推进中国式现代化进程中的重点、难点问题，中国政治经济学界开展系统深入研究，取得系列代表性成果。为准确刻画学界研究进展和轨迹，推动中国经济学理论体系的构建和完善，本刊精选议题如期奉上《中国政治经济学年度发展报告（2023.》。自2010年起，本刊连续十四年发布《中国政治经济学年度发展报告》，“年度发展报告”专栏已成为本刊标志性特色栏目。2023.报告聚焦12个专题，分为（上）（下）两篇，其中专题1—6于报告（上）篇刊登，专题7—12由报告（下）篇刊登。2023.报告（下）选题如下：

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Size distributions and magic number characteristics of cluster configurations formed during solidification processes of liquid metal Al

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Science china(Technological Sciences) 2006年第2期49卷 172-187页

作者： LIU Rangsu1, LIU Fengxiang1, DONG Kejun1, ZHENG Caixing1, LIU Hairong2, PENG Ping2 & LI Jiyong3.1. department of Physics, Hunan university, Changsha 410082, china 2. department of Material Science and Engineering, Hunan university, Changsha 410082, china 3. department of chemistry, Hunan university, Changsha 410082, china 1. department of Physics Hunan University Changsha 410082 China 2. department of Material Science and Engineering Hunan University Changsha 410082 China 3. department of chemistry Hunan University Changsha 410082 China

A molecular dynamics simulation study has been performed for a large systemconsisting of 100000 liquid metal Al atoms to investigate the formation and magic numbercharacteristics of the cluster configurations formed during the rapid solidification processes. Thecluster-type index method (CTIM) has been adopted to describe various types of clusterconfigurations. The results indicate that the icosahedral clusters (12 0 12 0) and theircombinations play the most important role in the rnicrostructure transitions during solidificationprocesses; for the cluster configurations of different levels formed by various combinations withdiffering numbers of basic clusters, their size distributions possess obvious magic number sequencewhich is in turn as 13.13., 19(21), 26-28(27), 3.-3.(3.), 3.-40, 43.44, 48..., (those in bracket arethe corresponding value in liquid state); the magic numbers correspond to the peak value positionsof the cluster numbers for corresponding level formed with various combinations by 1, 2, 3. 4, 5, 6,7, ...basic clusters, respectively. This magic number sequence is in good agreement with theexperimental results obtained by Harris et al. At the same time, this simulation study also gives ascientific and reasonable explanation to these experimental results.

关键词： liquid metal, solidification processes, cluster configuration, magic numbers, computer simulation.

Statistical properties for the vibrational energy levels of OCS

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Chinese Science Bulletin 2002年第8期47卷 641-643页

作者： XIE Daiqian & LU YuhuiInstitute of Theoretical and Computational chemistry, department of chemistry, Nanjing {3., Nanjing 210093. china department of chemistry, Sichuan {3., Chengdu 610064, china Institute of Theoretical and Computational chemistry Department of Chemistry Nanjing University Nanjing China department of chemistry Sichuan University Chengdu China

A potential energy surface for the electronic ground state of carbonyl sulfide was optimized by using a self-consistent configuration-interaction method and involving the recently observed vibrational band origins up to 8000 cm-1. With the optimized potential, the vibrational energy levels of OCS up to 15000 cm-1 were computed using the discrete variable representation method and Lanczos algorithm. Approximately 480 vibrational energy levels were identified. The statistical investigation showed that the vibrational energy levels of OCS up to 15000 cm-1 are largely regular.

关键词： OCS potential energy surface vibrational spectra sta-tistical property.

The regular representation and regular covariant representation of crossed products of Woronowicz C^(*)-algebras

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Science china Mathematics 2005年第9期48卷 1245-1259页

作者： ZHANG Xiaoxia~(1,2) & GUO Maozheng~(1,3. 1. School of Mathematical Sciences,Peking university,Beijing 100871,china 2. department of Mathematics,Yantai university,Yantai 264005,china 3. LMAM,Peking university,Beijing 100871,china 1. School of Mathematical Sciences Peking University 100871 Beijing China 2. department of Mathematics Yantai University 264005 Yantai China 3. LMAM Peking University 100871 Beijing China

In this paper,it is shown that the regular representation and regular covariant representation of the crossed products A×α G correspond to the twisted multiplicative unitary operators,where A is a Woronowicz C~*-algebra acted upon by a discrete group ***,it is also shown that the regular covariant C~*-algebra is the Woronowicz C~*-algebra which corresponds to a multiplicative ***,an explicit description of the multiplicative unitary operator for C(SU_q(2) )×α (?) is given in terms of those of the Woronowicz C~*-algebra C(SU_q(2) ) and the discrete group G.

关键词： multiplicative unitary operator, Woronowicz C*-algebra, crossed product.

SILYLATION OF CELLULOSE WITH TRICHLOROSILANE AND TRIETHOXYSILANE IN HOMOGENEOUS LiCl/N,N-DIMETHYLACETAMIDE SOLUTION

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Chinese Journal of Polymer Science 2000年第2期18卷 161-168页

作者： Hai-qing Liu Li-na Zhang department of chemistry, Wuhan university, Wuhan 43.072, {3. Wuhan Univ Dept Chem Wuhan 430072 Peoples R China

Silyl celluloses (SiC) were prepared by reacting cellulose with chloropropyltrichlorosilane (CPTCSi) and chloropropyltriethoxysilane (CPTESi) in LiCl/N,N-dimethylacetamide (DMAc). The Si content in the silyl cellulose could be controlled by adjustment of the molar ratio of silane and cellulose. FT-IR spectra showed that cellulose was readily reacted with the above two silane reagents, and the reactivity of CPTCSi is higher than that of CPTESi. It was presumed that the reaction process belongs to graft-polymerization. The results of differential thermal analysis (DTA) indicated that the thermostability of the materials produced increased with the increase of Si content in the sample. The acid resistance of the samples SiC in 1 mol/L HCl aqueous solution was improved significantly. When Si content was ca. 20%, the silyl cellulose has excellent thermostability, hydrophobicity, low density and stability in 1 mol/L HCl aqueous solution, owing to crosslinking of cellulose chain with silane.

关键词： sily cellulose chloropropyltrichlorosilane chloropropyltriethoxysilane LiCl/DMAc thermostability crosslinking