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Fishing Ground Distribution of Neon Flying Squid (Ommastrephes bartramii) in Relation to Oceanographic conditions in the Northwest Pacific Ocean

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Journal of Ocean University of china 2017年第6期16卷 1157-1166页

作者： YU Wei cHEN Xinjun YI qian college of Marine Sciences Shanghai Ocean University Shanghai 201306 P. R. China National Engineering Research center for Oceanic Fisheries Shanghai Ocean University Shanghai 201306 P. R. China Key Laboratory of Sustainable Exploitation of Oceanic Fisheries Resources Ministry of Education Shanghai Ocean University Shanghai 201306 P. R. China collaborative Innovation center for Distant-water Fisheries Shanghai Ocean University Shanghai 201306 P. R. China

Neon flying squid, Ommastrephes bartramii, is a squid species of the North Pacific Ocean, which plays an important economical role in the international fishery. Logbook data for chinese squid-jigging fishery over 2004–2011 were used to evaluate the relationship between the fishing grounds of the squid and the convergent frontal areas, which were defined by the contour lines of specific sea surface temperature(SST) and chlorophyll-a(chl-a) concentration. Our results indicate that the SST in the range of 15 to 19℃ and the chl-a concentration in the range of 0.1 to 0.4 mg m^(-3) are the favorable conditions for the aggregation of the squid. Additionally, we deduced that the SST at 17.5℃ and the chl-a concentration at 0.25 mg m^(-3) are the optimal environmental conditions for the aggregation of O. bartramii. In August, the annual cPUE is positively correlated with the proportion of the fishing grounds with favorable SST and chl-a concentration, as well as the combination of the two variables, implying that the abundance of the squid annually is largely depending on the presence of the favorable environmental conditions for fishery in August. Minor spatial difference between mean latitudinal location of the 17.5℃ SST and 0.25 mg m^(-3) chl-a fronts can increase the cPUEs of O. bartramii. Furthermore, the monthly latitudinal gravity centers of the cPUE closely followed the mean latitudinal position of the contour lines of the 17.5℃ SST and the 0.25 mg m^(-3) chl-a concentration. Our findings suggest the convergent oceanographic features(fronts) play significant roles in regulating the distribution and abundance of the western stock of the winter-spring cohort of O. bartramii, which can help people to improve their ability to discover the O. bartramii fishing grounds with higher productivity.

关键词： neon flying squid sea surface temperature chlorophyll-a oceanic fronts fishing ground the Northwest Pacific Ocean

A Solvability criterion for Finite Groups

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Acta Mathematica Sinica,English Series 2016年第8期32卷 982-992页

作者： Guo Hua qian Tian Ze LI Department of Mathematics Changshu Institute of Technology

We show that if for every prime p, the normalizer of a Sylow p-subgroup of a finite group G admits a p-solvable supplement, then G is solvable. This generalizes a solvability criterion of Hall which asserts that a fin... 详细信息

关键词： Finite group solvable group Sylow normalizer supplement

Smoothing of Fast Assembled Layer-by-layer Films by Adjusting Assembly conditions

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chemical Research in chinese Universities 2015年第4期31卷 674-679页

作者： DUANYang AN Oi ZHANG qian ZHANG Yihe Beijing Key Laboratory of Materials Utilization of Nonmetallic Minerals and Solid Wastes National Laboratory of Mineral Materials School of Materials Science and Technology China University of Geosciences Beijing 100083 P. R. China

To prepare layer-by-layer（LbL） multilayers in time-efficient manners by the dipping method is highly ap- pealing. However, the fast LbL assembly produces multilayers with high surface roughness. In our attempt to smooth the surface morphologies of LbL multilayers obtained by fast assembly（5 s dipping）, we studied the influence of the assembly conditions on the surface morphologies. The study shows that by properly adjusting the assembly condi- tions, such as washing duration, water annealing period, and drying with nitrogen flow, LbL multilayers with en- hanced surface smoothness could be obtained through fast LbL assembly.

关键词： Layer-by-layer self-assembly Surface morphology Water annealing Nitrogen flow

A new index to describe the tropical Asian summer monsoon

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Science china Earth Sciences 2009年第6期52卷 843-854页

作者： ZhongFeng Xu congBin Fu YongFu qian Key Laboratory of Regional climate-Environment Research for Temperate East Asia (RcE-TEA) Institute of Atmospheric Physics Chinese Academy of Sciences Beijing 100029 China School of Atmospheric Sciences Nanjing University Nanjing 210093 C

We define a new monsoon index (MV) as the product of relative vorticity and equivalent potential temperature using the long-term NcEP/NcAR reanalysis data. The MV index provides new insights into the intraseasonal and... 详细信息

关键词： tropical Asian summer monsoon monsoon index intraseasonal variability interannual variability

The Accelerated Thermo-Oxidative Aging characteristics of Wood Fiber/Polycaprolactone composite:Effect of Temperature,Humidity and Time

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Journal of Renewable Materials 2021年第12期9卷 2209-2222页

作者： Shuang Si qian Tang Xingong Li central South University of Forestry and Technology Changsha410004China

This study investigated the characteristics of wood fiber/polycaprolactone composite after an artificial accelerated thermo-oxidative aging *** effect of time,temperature and humidity during the treatment on their mechanical,chemical and morphology properties were *** composite was prepared from melted wood fibers and modified polycaprolactone by a molding process.A temperature and humidity controllable test chamber was used for the thermo-oxidative aging of the *** thermo-oxidative aging caused surface of the composite to be much more rougher and even a few cracks and holes appeared on *** to the spectra of Fourier Transform Infrared(FTIR)and Gel Permeation chromatography(GPc),c=O in the molecular chain of polycaprolactone was hydrolyzed and c–O was broken after the aging treatment,which resulted in a reduction in average molecular weight of the ***,results showed that the mechanical strength decreased a lot with the increase in time,temperature and humidity,and the effect of temperature and humidity was more significant compared with that of *** the temperature and humidity during thermo-oxidative aging treatment could accelerate the aging of composite,which provided a quick and effective method for evaluating the aging resistance of the composite.

关键词： Wood fiber polycaprolactone wood plastic composite thermo-oxidative aging

Ultrafast Optical Properties of c_(70) Thin Film

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chinese Physics Letters 1996年第9期13卷 668-671页

作者： WANG cong-fang AXi-cheng XIA Zong-ju ZOU Ying-hua qian Jiang qian Shi-xiong Department of Physics Mesoscopic Physics LaboratoryPeking UniversityBeijing 100871 Department of Physics fudan UniversityShanghai 200433

The relaxation of optically excited carrier in c_(70) thin film fabricated by physical jet deposition was investigated by femtosecond pump-probe measurements.A transient decrease in transmission was observed indicating induced *** comparison to c_(60) thin film the initial response of c_(70) film is laser pulse limited and the long lived component has smaller *** third order optical nonlinear susceptibility of c_(70) thin film was determined to be χ^((3))=3.3×10^(-11) esu by femtosecond time-resolved optical Kerr *** the primarily pulse limited response the dephasing time of c_(70) thin film has been proved to be shorter than the laser pulse width.

关键词： pulse pump film

Influence of Superplasticizer Type and Dosage on Early-age Drying Shrinkage of cement Paste with consideration of Pore Size Distribution and Water Loss

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Journal of Wuhan University of Technology(Materials Science) 2020年第4期35卷 758-767页

作者： qian Xiaoqian YU congdi ZHANG Lifeng qian Kuangliang FANG Minghui LAI Junying college of civil Engineering and Architecture Zhejiang UniversityHangzhou 310058China

We introduced a parameter r_s(the radius of the pores where the meniscus forms),which is composed of two factors,i e,water loss and cumulative pore size distribution(PSD),to provide a better explanation of the influence of superplasticizers(SPs)on early-age drying *** our experiments,it is found that the addition of three types of SPs leads to a significant increase in the early-age drying shrinkage of cement paste,and drying shrinkage increases with the dosage of *** on the results above,we further studied the mechanism of the effects of SPs on the early-age drying shrinkage of cement paste by PSD and water loss,which are two components of r_*** experimental results indicate that r_s can be a better index for the early-age drying shrinkage of cement-based materials with SPs than a single *** addition,the effects of SPs on other factors such as hydration degree and elastic modulus were also investigated and discussed.

关键词： superplasticizer early-age drying shrinkage water loss pore size distribution

Molecular barriers to direct cardiac reprogramming

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Protein & cell 2017年第10期8卷 724-734页

作者： Haley Vaseghi Jiandong Liu Li qian Department of Pathology and Laboratory Medicine McAllister Heart Institute University of North CarolinaChapel Hill NC 27599 USA

Myocardial infarction afflicts close to three quarters of a million Americans annually, resulting in reduced heart function, arrhythmia, and frequently death. cardiomy- ocyte death reduces the heart＇s pump capacity while the deposition of a non-conductive scar incurs the risk of arrhythmia. Direct cardiac reprogramming emerged as a novel technology to simultaneously reduce scar tissue and generate new cardiomyocytes to restore cardiac function. This technology converts endogenous cardiac fibroblasts directly into induced cardiomyocyte-like cells using a variety of cocktails including transcription factors, microRNAs, and small molecules. Although promising, direct cardiac reprogramming is still in its fledging phase, and numerous barriers have to be overcome prior to its clinical application. This review discusses current findings to optimize reprogramming efficiency, including reprogramming factor cocktails and stoichiometry, epigenetic barriers to cell fate reprogramming, incomplete conversion and residual fibroblast identity, requisite growth factors, and environmental cues. Finally, we address the current challenges and future directions for the field.

关键词： cardiac reprogramming myocardia infarction epigenetics heart regeneration

Rhodium-catalyzed N-Arylation Addition of Arylboronic Acids to Ketimines

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chinese Journal of chemistry 2024年第18期42卷 2243-2248页

作者： Xue-Wei qian Xing-Wen Sun Department of chemistry Fudan University220 Handan RoadShanghai 200433China

Herein,we report rhodium catalyzed N-arylation via addition of arylboronic acids to electron-deficientα-iminoesters which can be prepared in high efficiency by using easily accessible B-carbonyl *** reaction is highly regiospecific to achieve the N-aryl addition efficiently with up to 99%yield under mild *** corresponding product can be further efficiently converted into indoles andaseries of other important building blocks.

关键词： Rhodium catalyzed N-Arylation addition Amines Umpolung Indole c-c coupling