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Photopromoted methoxycarbonylation of olefin with methyl formate by Co(OAc)2

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Chinese Chemical Letters 2007年第1期18卷 17-20页

作者： ying na cui Jing Mei Yin Da Bin Gao ying Ping Jia Guang Yun Zhou Shen Min Li Liaoning Key Laboratory of Bio-Organic Chemistry Dalian University Dalian 116622 China

The photopromoted methoxycarbonylation of olefin with methyl formate catalyzed by Co（OAc）2 at ambient conditions has been carried out. The results indicated that the reaction activity increased with the increasing temperature. Methyl formate decomposed into CO and CH3OH firstly under irradiation, and then the methoxycarbonylation of olefin proceeded under catalysis of Co（OAc）2. The mechanism of methyl formate participating in the methoxycarbonylation is verified by the IR analysis and the labeling experiments of CDHOD and CH3^18OH.

关键词： Mcthoxycarbonylation Methyl formate Olefin Photopromoted Cobalt acetate

Photopromoted carbonylation of bromobenzene under ambient conditions

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Chinese Chemical Letters 2009年第5期20卷 531-534页

作者： Li Zhuo Mu ying Ping Jia Jing Mei Yin Guang Yun Zhou ying na cui Da Bin Gao Liaoning Key Laboratory of Bio-organic Chemistry Dalian University Dalian 116622 China

The photopromoted carbonylation of bromobenzene with carbon monoxide catalyzed by inexpensive commercially available cobalt salts [Co（OAc）2, COCl2] was carried out under ambient conditions. The results revealed that methyl benzoate was produced in the presence of basic additives （CH3Ona, naOAc or （n-C4H9）3N）. The catalytic activity of Co（OAc）2 was higher than that of COCl2. Furthermore, the activity of the carbonylation was greatly improved by addition of acetophenone, e.g. both the yield and selectivity of the ester were increased from 47% to 91% with Co（OAc）2 as catalyst and CH3Ona as additive, while the yield of byproduct benzene from hydrodehalogenation of bromobenzene decreased from 32% to 8%.

关键词： Photopromoted carbonylation Bromobenzene Cobalt salts Sodium methoxide Acetophenone

Photopromoted carbonylation of 1-bromo-6-chlorohexane under ambient conditions

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Chinese Chemical Letters 2008年第5期19卷 529-532页

作者： Yao Yun Hu Jing Mei Yin Da Bin Gao ying Ping Jia Guang Yun Zhou ying na cui Shen Min Li Liaoning Key Laboratory of Bio-organic Chemistry Dalian University Dalian 116622 China

Photopromoted carbonylation of 1-bromo-6-chlorohexane with CO catalyzed by CuBr2 and CdI2 has been carried out under ambient conditions. The results indicate that the carbonylation proceeds with the major product of chloroester ClCH2（CH2）5COOCH3 under catalysis of CuBr2. Furthermore, the activity of the carbonylation can be improved by addition of basic additives （naOAc, na3PO4 or （n-C4H9）3N）. Among these additives, （n-C4H9）3N is the most efficient in terms of the yield of ClCH2（CH2）5COOCH3. However, the methoxycarbonyl substituting chlorine product of BrCH2（CH2）5COOCH3 is not obtained in the presence of CdI2. This is quite different from the carbonylation of monochloroalkane.

关键词： Photopromoted carbonylation 1-Bromo-6-chlorohexane Copper bromide Tri-n-butylamine

Cobalt-catalyzed photopromoted carbonylation of chloroalkanes in the presence of KI

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Chinese Chemical Letters 2010年第9期21卷 1033-1036页

作者： ying Ping Jia ying na cui Jing Mei Yin Guang Yun Zhou Shen Min Li Da Bin Gao Xiang Sheng Wang State Key Laboratory of Fine Chemicals Dalian University of Technology. Dalian 116012 China Liaoning Key Laboratory of Bio-organic Chemistry Dalian University Dalian 116622China

The photopromoted carbonylation of chloroalkanes with carbon monoxide catalyzed by cobalt compounds[Co（OAc）2,CoCl2] in the presence of KI was carried out under ambient *** results revealed that the catalytic activity of Co（OAc）2 was higher than that of CoCl2.A basic additive naOAc was beneficial to the ***,with naOAc as an additive, Co（OAc）2 and CoCl2 exhibited similar catalytic *** work showed that the role of iodide ion was initially to form active iodoalkanes via substituting chloride ion in chloroalkanes in situ,and then,the carbonylation of iodoalkanes proceeded under irradiation.

关键词： Photopromoted carbonylation Chloroalkanes Cobalt complexes: KI

A COMPLETE CHARACTERIZATION OF THE ROBUST ISOLATED CALMNESS OF NUCLEAR NORM REGULARIZED CONVEX OPTIMIZATION PROBLEMS

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Journal of Computational Mathematics 2018年第3期36卷 441-458页

作者： ying cui Defeng Sun The Daniel J. Epstein Department of Industrial and Systems Engineering University of Southern California Los Angeles California USA Department of Applied Mathematics The Hong Kong Polytechnic University Hung Hom Hong Kong

In this paper, we provide a complete characterization of the robust isolated calmness of the Karush-Kuhn-Tucker （KKT） solution mapping for convex constrained optimization problems regularized by the nuclear norm function. This study is motivated by the recent work in [8], where the authors show that under the Robinson constraint qualification at a local optimal solution, the KKT solution mapping for a wide class of conic programming problems is robustly isolated calm if and only if both the second order sufficient condition （SOSC） and the strict Robinson constraint qualification （SRCQ） are satisfied. Based on the variational properties of the nuclear norm function and its conjugate, we establish the equivalence between the primal/dual SOSC and the dual/primal SRCQ. The derived results lead to several equivalent characterizations of the robust isolated calmness of the KKT solution mapping and add insights to the existing literature on the stability of nuclear norm regularized convex optimization problems.

关键词： Robust isolated calmness Nuclear norm Second order sufficient condition Strict Robinson constraint qualification

Identifying the Key Reference of a Scientific Publication

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Journal of Systems Science and Systems Engineering 2020年第4期29卷 429-439页

作者： Haochuan cui An Zeng ying Fan Zengru Di School of Systems Science Beijing Normal UniversityBeijing 100875P.R.China School of systems science Beijing Normal UniversityBeijing 100875P.R.China

The most fundamental way to measure the impact of a scientific publication is using the number of citations it *** citation count and its variants are widely adopted,they have been pointed out to be poor proxies for a paper's quality because a citation might result from different *** is thus crucial to quantify the true relevance of the cited papers to the citing *** are already some eforts in the literature devoted to addressing this isue,yet a well-accepted method is still lacking,possibly due to the absence of standard ground truth data for comparing different *** this paper,we propose a simple method using a local diffusion process on citation networks for identifying the key references for each scientific *** effectiveness and of the method are validated in a subset of the American Physical Society data in which the key references are mentioned in the abstract of *** further define an effective citation metric for quantifying the actual impact of each paper and its *** effective citation metric additionally reveals the citation preference of research at journal and country levels.

关键词： Network diffusion paper abstract citation network effective citations

Carbon cycle variability in tropical Atlantic across two Early Eocene hyperthermals

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Geoscience Frontiers 2021年第2期12卷 521-530页

作者： Shijun Jiang ying cui Yasu Wang Institute of Groundwater and Earth Sciences Jinan UniversityGuangzhou510632China Southern Marine Science and Engineering Guangdong Laboratory(Zhuhai) Zhuhai519082China Department of Earth and Environmental Studies Montclair State UniversityMontclairNJ07043USA

Early Eocene hyperthermals are geologically short-lived global warming events and represent fundamental perturbations to the global carbon cycle and the Earth’s ecosystem due to massive additions of isotopically light carbon to the ocean-atmosphere *** serve as ancient analogs for understanding how the oceanic carbonate system and surface-ocean ecosystem would respond to ongoing and future climate ***,we present a continuous carbonate record across the Eocene Thermal Maximum 2(ETM2 or H1,ca.54.1 Ma)and H2(ca.54 Ma)events from an expanded section at Ocean Drilling Program Site 1258 in tropical *** abundant calcareous nannofossils and moderate carbonate content throughout the studied interval suggest this record was deposited above the calcite compensation depth(CCD),but below the lysocline and under the influence of terrestrial *** Earth system model cGENIE is used to simulate the carbon cycle dynamics across the ETM2 and H2 to offer insights on the mechanism of the rapid warming and subsequent recovery in climate and *** model suggests moderate changes in ocean pH(0.1–0.2 unit)for the two scenarios,biogenic methane from a rechargeable methane capacitor and organic matter oxidation from thawing of the *** pH changes are consistent with a recent independent pH estimate across the ETM2 using boron *** carbon emission flux during the ETM2 is at least an order of magnitude smaller than that during the Paleocene–Eocene Thermal Maximum(PETM)(0.015–0.05 Pg C yr^(-1)vs.0.3–1.7 Pg C yr^(-1)).The comparable pre-and post-event carbonate contents suggest the lysocline did not over deepen following the ETM2 at this tropical Atlantic site,indicating spatial heterogeneity in the carbonate system due to strong dilution influence from terrestrial weathering and riverine discharge at Site 1258.

关键词： Early Eocene hyperthermals Oceanic carbonate system Stable carbon and oxygen isotopes Earth system modeling Tropical Atlantic cGENIE

Structure and function of neuropeptide F in insects

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Journal of Integrative Agriculture 2020年第6期19卷 1429-1438页

作者： cui Hong-ying ZHAO Zhang-wu Department of Entomology/MOA Key Lab of Pest Monitoring and Green Management College of Plant ProtectionChina Agricultural UniversityBeijing 100193P.R.China

In sect n europeptides are a group of brain n euro-regulatory factors,which plays very important roles in growth and developme nt,molting and metamorphosis,as well as mating and *** neuropeptide F(NPF),a multi-functional neuropeptide,is one of neuropeptides identified in numerous insect species,which plays important roles in feeding,metabolism,courtship,reproduction,aggression,ethanol sensitivity,locomotor circadian rhythms,learning and stress *** roles of NPF are implemented through NPF receptors(NPFR).The NPFR1,a G protein-coupled receptor with 7 transmembrane domai ns,is one of these receptors and is found to be imports nt for NPF *** NPF usually is con sisted of around 36-40 amino acid residues,but the short neuropeptide F(sNPF)consisted of 7-16 amino acid residues have also been found in some *** this review,the structure and function of both NPF and sNPF in in sects are discussed.

关键词： neuropeptide NPF sNPF NPFR1 insects

Empirical Likelihood of Quantile Difference with Missing Response When High-dimensional Covariates Are Present

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Acta Mathematica Sinica,English Series 2021年第12期37卷 1803-1825页

作者： cui Juan KONG Han ying LIANG School of Mathematical Sciences Tongji UniversityShanghai 200092P.R.China

We,in this paper,investigate two-sample quantile difference by empirical likelihood method when the responses with high-dimensional covariates of the two populations are missing at *** particular,based on sufficient dimension reduction technique,we construct three empirical log-likelihood ratios for the quantile difference between two samples by using inverse probability weighting imputation,regression imputation as well as augmented inverse probability weighting imputation,respectively,and prove their asymptotic *** the same time,we give a test to check whether two populations have the same distribution.A simulation study is carried out to investigate finite sample behavior of the proposed methods too.

关键词： Empirical likelihood high-dimensional missing at random sufficient dimension reduction two-sample quantile difference