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Fatty acid profiles of muscle from large yellow croaker (Pseudosciaena crocea R.) of different age

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Journal of Zhejiang University-Science B(Biomedicine & Biotechnology) 2009年第2期10卷 154-158页

作者： Hong-gang TANG Li-hong CHEN chao-geng xiao Tian-xing WU Zhejiang Academy af Agricultural Sciences Hangzhou 310021 China Department of Chemistry Zhejiang University Hangzhou 310027 China

We investigated the fatty acid profiles of muscle from large yellow croaker （Pseudosciaena crocea R.） of different age. One- and two-year-old fish were cultured in floating net cages and sampled randomly for analysis. Moisture, protein, lipid and ash contents were determined by methods of Association of Analytical Chemist （AOAC） International. Fatty acid profile was deter- mined by gas chromatography. Crude protein, fat, moisture and ash contents showed no significant differences between the two age groups. The contents of total polyunsaturated fatty acids and docosahexaenoic acid （DHA） were significantly higher and eicosapentaenoic acid （EPA） content was significantly lower in the two-year-old large yellow croaker than in the one-year-old （/＇〈0.05）. No significant differences were observed in the contents of total saturated fatty acids and monounsaturated fatty acids, or the ratio ofn-3/n-6 fatty acids among the large yellow croakers of the two age groups. We conclude that large yellow croakers are good food sources of EPA and DHA.

关键词： Fatty acid Large yellow croaker Age

Microstructure and mechanical properties of nickel-based superalloy fabricated by laser powder-bed fusion using recycled powders

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International Journal of Minerals,Metallurgy and Materials 2021年第2期28卷 266-278页

作者： De-cheng Kong chao-fang Dong xiao-qing Ni Liang Zhang Rui-xue Li Xing He Cheng Man xiao-gang Li Beijing Advanced Innovation Center for Materials Genome Engineering University of Science and Technology BeijingBeijing 100083China Shanghai Engineering Research Center of 3D Printing Materials Shanghai Research Institute of MaterialsShanghai 200437China School of Materials Science and Engineering Ocean University of ChinaQingdao 266100China

Evaluating the recyclability of powders in additive manufacturing has been a long-term *** this study,the microstructure and mechanical properties of a nickel-based superalloy fabricated by laser powder-bed fusion(LPBF)using recycled powders were ***-melted powder surfaces,satellite particles,and deformed powders were found in the recycled powders,combined with a high-oxygencontent surface *** increasing oxygen content led to the formation of high-density oxide inclusions;moreover,printing-induced cracks widely occurred and mainly formed along the grain boundaries in the as-built LPBF nickel-based superalloys fabricated using recycled powders.A little change in the Si or Mn content did not increase the hot cracking susceptibility(HCS)of the printed *** changing aspect ratio and the surface damage of the recycled powders might contribute to increasing the crack ***,the configuration of cracks in the as-built parts led to anisotropic mechanical properties,mainly resulting in extremely low ductility vertical to the building direction,and the cracks mainly propagated along the cellular boundary owing to the existence of a brittle precipitation phase.

关键词： laser powder-bed fusion recycled powder cracking anisotropy nickel-based superalloy

Benzothiadiazole-based Conjugated Polymers for Organic Solar Cells

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Chinese Journal of Polymer Science 2021年第5期39卷 525-536,I0004页

作者： chao Wang Feng Liu Qiao-Mei Chen Cheng-Yi xiao Yong-gang Wu Wei-Wei Li College of Chemistry and Environmental Science Hebei UniversityBaoding 071002China Beijing Advanced Innovation Center for Soft Matter Science and Engineering&State Key Laboratory of Organic-Inorganic Composites Beijing University of Chemical TechnologyBeijing 100029China

Benzothiadiazole(BT)is an electron-deficient unit with fused aromatic core,which can be used to construct conjugated polymers for application in organic solar cells(OSCs).In the past twenty years,huge numbers of conjugated polymers based on BT unit have been developed,focusing on the backbone engineering(such as by using different copolymerized building blocks),side chain engineering(such as by using linear or branch side units),using heteroatoms(such as F,O and S atoms,and CN group),*** modifications enable BT-polymers to exhibit distinct absorption spectra(with onset varied from 600 nm to 1000 nm),different frontier energy levels and *** a consequence,BT-polymers have gained much attention in recent years,and can be simultaneously used as electron donor and electron acceptor in OSCs,providing the power conversion efficiencies(PCEs)over 18%and 14%in non-fullerene and all-polymer *** this article,we provide an overview of BT-polymers for OSCs,from donor to acceptor,via selecting some typical BT-polymers in different *** hope that the summary in this article can invoke the interest to study the BT-polymers toward high performance OSCs,especially with thick active layers that can be potentially used in large-area devices.

关键词： Benzothiadiazole Conjugated polymer Organic solar cells Electron donor Electron acceptor

Statistical analysis and modeling of residential buildings for artificial Beijing reconstruction

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International Journal of Modeling, Simulation, and Scientific Computing 2016年第2期7卷 63-74页

作者： Zhi-chao Song Rong-Qing Meng Hong Duan xiao-gang Qiu College of Information System and Management National University of Defense Technology Changsha Hunan 410073P.R.China

Environment model is an important component of an artificial *** level up the resolution of residence-building environment models in artificial Beijing,we divide residential buildings in Beijing into two categories,which are noncommunity residential buildings and community residential buildings,and statistically analyze the numbers of floors and areas of the real residential *** this paper,we have exhibited the distribution of numbers of floors in noncommunity residential buildings and community residential ***,we analyze the distribution of areas of noncommunity residential buildings and residence-use proportions of community zones by Nonlinear *** indicate that areas of noncommunity residential buildings in Beijing obey the log-normal distribution and residence-use proportions of community zones obey normal *** to the statistical models,the virtual residential buildings in artificial Beijing can be endowed with rational attribute values.

关键词： Data-driven modeling artificial society environment modeling residential buildings

A theory of 2+1D bosonic topological orders

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National Science Review 2016年第1期3卷 68-106页

作者： xiao-gang Wen Perimeter Institute for Theoretical Physics Department of Physics Massachusetts Institute of Technology

In primary school, we were told that there are four phases of matter: solid, liquid, gas, and plasma. In college,we learned that there are much more than four phases of matter, such as hundreds of crystal phases, liquid crystal phases, ferromagnet, anti-ferromagnet, superfluid, etc. Those phases of matter are so rich, it is amazing that they can be understood systematically by the symmetry breaking theory of Landau. However,there are even more interesting phases of matter that are beyond Landau symmetry breaking theory. In this paper, we review new ‘topological’ phenomena, such as topological degeneracy, that reveal the existence of those new zero-temperature phase—topologically ordered phases. Microscopically, topologically orders are originated from the patterns of long-range entanglement in the ground states. As a truly new type of order and a truly new kind of phenomena, topological order and long-range entanglement require a new language and a new mathematical framework, such as unitary fusion category and modular tensor category to describe them. In this paper, we will describe a simple mathematical framework based on measurable quantities of topological orders(S, T, c) proposed around 1989. The framework allows us to systematically describe all 2+1D bosonic topological orders(i.e. topological orders in local bosonic/spin/qubit systems).

关键词： quantum matter topological order long range entanglement modular tensor category

Stand establishment,root development and yield of winter wheat as affected by tillage and straw mulch in the water deficit hilly region of southwestern China

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Journal of Integrative Agriculture 2016年第7期15卷 1480-1489页

作者： LI chao-su LI Jin-gang TANG Yong-lu WU xiao-li WU Chun HUANG gang ZENG Hui Crop Research Institute Sichuan A cademy of Agricultural SciencesChengdu 610066P.R.China College of Agriculture Sichuan Agricultural UniversityWenjiang 611130P.R.China Agricultural Bureau of Jianyang City Jianyang 621700P.R.China

Good crop stand establishment and root system development are essential for optimum grain yield of dryland wheat （Triti-cum aestivumL.）. At present, little is known about the effect of tilage and straw mulch on the root system of wheat under dryland areas in southwestern China. The aim of this study was to evaluate the effect of three tilage treatments （no-til, NT; rotary til, RT; conventional til, CT） and two crop residue management practices （straw mulch, ML; non-straw mulch, NML） on stand establishment, root growth and grain yield of wheat. NT resulted in lower soil cover thickness for the wheat seed, higher number of uncovered seeds, lower percentage of seedling-less ridges and lower tiler density compared to RT and CT; ML resulted in higher tiler density compared to NML. Straw mulching resulted in more soil water content and root length density （RLD） at most of the growth stages and soil depths. The maximum RLD, root surface area density and root dry matter density were obtained under NT. In the topmost 10 cm soil layer, higher RLD values were found under NT than those under RT and CT. There were no signiifcant differences in the yield or yield components of wheat among the tilage treatments in 2011–2012, but NT resulted in a signiifcant higher yield compared to RT and CT in 2012–2013. Grain yield was signiifcantly higher in ML compared to in NML. A strong relationship was observed between the water-use efifciency and the grain yield. Both NT and ML proved beneifcial for wheat in term of maintaining higher tiler density, better soil water status and root growth, leading to a higher grain yield and enhanced water-use efifciency, especialy in a low rainfal year.

关键词： wheat tilage mulch stand establishment yield Triticum aestivum

A multiaxial lead-free two-dimensional organic-inorganic perovskite ferroelectric

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National Science Review 2021年第5期8卷 140-146页

作者： chao-Ran Huang Xuzhong Luo xiao-gang Chen Xian-Jiang Song Zhi-Xu Zhang Ren-Gen Xiong Key Laboratory of OrganoPharmaceutical Chemistry of Jiangxi Province College of Chemistry and Chemical EngineeringGannan Normal University Jiangsu Key Laboratory for Science and Applications of Molecular Ferroelectrics Southeast University

Two-dimensional(2 D) hybrid organic-inorganic perovskites(HOIPs) have recently gained tremendous interest because of their unique features in contrast to three-dimensional counterparts and traditional 2 D materials. However, although some 2 D HOIP ferroelectrics have been achieved, the issue of toxic Pb and uniaxial nature impede their further application. Herein, for the first time, we report a lead-free 2 D HOIP multiaxial ferroelectric, [3,3-difluorocyclobutylammonium]2CuCl4(1), which shows four ferroelectric axes and eight equivalent polarization directions, more than those of the other 2 D HOIP ferroelectrics and even the inorganic perovskite ferroelectric BaTiO3(three ferroelectric axes and six equivalent polarization directions). 1 also features a high Curie temperature of 380 K and exhibits remarkable thermochromism of color change from green-yellow to dark brown. To our knowledge, 1 is the first multiaxial lead-free2 D HOIP ferroelectric. This work sheds light on the exploration of better lead-free 2 D HOIP ferroelectrics.

关键词： ferroelectrics organic-inorganic perovskites multiaxial ferroelectrics Curie temperature thermochromism

A Lattice Non-Perturbative Definition of an SO(10) Chiral Gauge Theory and Its Induced Standard Model

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Chinese Physics Letters 2013年第11期30卷 54-58页

作者： WEN xiao-gang Perimeter Institute for Theoretical Physics WaterlooOntario N2L 2Y5Canada Department of Physics Massachusetts Institute of TechnologyCambridgeMassachusetts 02139USA

The standard model is a chiral gauge theory where the gauge fields couple to the right-hand and the left-hand fermions *** standard model is defined perturbatively and describes all elementary particles(except gravitons)very ***,for a long time,we do not know if we can have a non-perturbative definition of the standard model as a Hamiltonian quantum mechanical *** we propose a way to give a modified standard model(with 48 two-component Weyl fermions)a non-perturbative definition by embedding the modified standard model into an SO(10)chiral gauge *** show that the SO(10)chiral gauge theory can be put on a lattice(a 3D spatial lattice with a continuous time)if we allow fermions to *** a non-perturbatively defined standard model is a Hamiltonian quantum theory with a finite-dimensional Hilbert space for a finite space *** generally,using the defining connection between gauge anomalies and the symmetry-protected topological orders,one can show that any truly anomaly-free chiral gauge theory can be non-perturbatively defined by putting it on a lattice in the same dimension.

关键词： theory gauge chiral

Electrochemical corrosion failure mechanism of M152 steel under a salt-spray environment

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International Journal of Minerals,Metallurgy and Materials 2015年第11期22卷 1183-1189页

作者： Pan Yi Kui xiao Kang-kang Ding Xu Wang Li-dan Yan Cheng-liang Mao chao-fang Dong xiao-gang Li Corrosion and Protection Center University of Science and Technology Beijing Institute of Advanced Materials and Technology University of Science and Technology Beijing State Key Laboratory for Marine Corrosion and Protection Luoyang Ship Material Research Institute Ningbo Institute of Material Technology & Engineering Chinese Academy of Sciences

The corrosion failure mechanism of M152 was studied using the neutral salt-spray test to better understand the corrosion behavior of 1Cr12Ni3Mo2VN（M152）, provide a basis for the optimization of material selection, and prevent the occurrence of failure. Moreover, the mechanism was investigated using the mass loss method, polarization curves, electrochemical impedance spectroscopy（EIS）, stereology microscopy, scanning electron microscopy, and energy-dispersive X-ray spectroscopy（EDS）. The results show that M152 steel suffers severe corrosion, especially pitting corrosion, in a high-salt-spray environment. In the early stage of the experiment, the color of the corrosion products was mainly orange. The products then gradually evolved into a dense, brown substance, which coincided with a decrease of corrosion rate. Correspondingly, the EIS spectrum of M152 in the late test also exhibited three time constants and presented Warburg impedance at low frequencies.

关键词： heat-resistant steel electrochemical corrosion failure mechanism salt spray test