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Differentiability of Functions on Spheres and Criterions of Convexity

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Wuhan University Journal of Natural Sciences 2022年第4期27卷 273-280页

作者： CHEN Tingting guo qi Department of Mathematics Suzhou University of Science and TechnologySuzhou 215009JiangsuChina

Some basic concepts for functions defined on subsets of the unit sphere,such as the s-directional derivative,s-gradient and s-Gateaux and s-Frechet differentiability etc,are introduced and *** concepts are different from the usual ones for functions defined on subsets of Euclidean spaces,however,the results obtained here are very ***,as applications,we provide some criterions of s-convexity for functions defined on unit spheres which are improvements or refinements of some known results.

关键词： spherical convexity spherically convex function Gateaux and Frechet differentiability criterion of convexity

Compositions and Transformations on Spherical Convex Sets

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Wuhan University Journal of Natural Sciences 2020年第4期25卷 277-285页

作者： zhOU Xia guo qi Department of Mathematics Suzhou University of Science and TechnologySuzhou 215009JiangsuChina

In this paper,we first study some compositions/transformations,such as the scalar-multiplication,spherical addition and canonical transformation,etc.,on the unit sphere of Euclidean spaces,and in turn on spherically convex sets in the unit *** we study valuations on the families of spherically convex *** particular,we show that the spherical projections defined recently by Ferreira et al are valuations in some cases.

关键词： spherical convexity radial projection projection to sphere valuation

Atomistic simulation of the structural evolution in magnesium single crystal under c-axis tension

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Acta Metallurgica Sinica(English Letters) 2011年第6期24卷 487-494页

作者： Honggang qi Yafang guo Xiaozhi TAng Shuang XU Institute of Engineering Mechanics Beijing Jiaotong University Beijing 100044 China

Molecalar dynamics simulation is applied to investigate the microstructure evolution of magnesium single crystals under c-axis extension at different temperatures. At low temperatures, both {1012} and {1011} twins are observed. At elevated temperatures, {1011} twining decreases quickly with increasing temperature, while the amount of {1012} twins increases. The （1012} twin is found to be the main deformation mechanism under the c-axis tension in the magnesium single crystal. Meanwhile, shear bands are also observed during deformation. When the temperature is beyond 500 K, the non-basal plane slip due to the thermal .activation is found. The stress-strain curves related with deformation behavior at atomistic scale are presented.

关键词： Magnesium single crystal Twinning Molecular dynamics simu-lation c-axis tension

Bionic stab-resistant body armor based on triangular pyramid structure

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Defence Technology（防务技术） 2021年第3期17卷 792-799页

作者： Ya-xin guo Meng-qi Yuan Xin-ming qian State Key Laboratory of Explosion Science and Technology Beijing Institute of TechnologyBeijing100081China

A stab-resistant substrate was designed and realized with a triangular pyramidal structure, inspired by the biological armor model in nature. The stab-resistance behavior and dynamic response mechanisms were studied through numerical simulation and experimental testing of a knife impacting a substrate,and an optimal structural design was obtained accordingly, with a tilted angle of 22.5and optimal thickness of 1.2 mm. It was shown that the triangular pyramidal structure generated twice the internal energy of the knife than the flat substrate due to the dispersing effect of the structure. The force parallel to the inclination caused a significant scratch on the substrate surface, while the force perpendicular caused obvious substrate deformation. A new riveting method was used to form the total layer, which passed the GA 68-2008 standard. The stab-resistant clothing coupled with the reduced wearing burden could provide effective protection and avoid fatal injuries on security personnel working in dangerous environments. The method provided may enlighten the future design and manufacturing of stabresistant clothing.

关键词： Stab resistant Impact behavior Body armor Finite element analysis

Theoretical Study of the AIEt3-Promoted Tandem Reductive Rearrangement of Epoxides

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Chinese Journal of Chemical Physics 2008年第6期21卷 547-554页

作者： Li-dong zh.ng Hui-jun guo Yang Pan Fei qi National Synchrotron Radiation Laboratory University of Science and Technology of China Hefei 230029 China

The AIEt3-promoted tandem reductive rearrangement reactions of epoxides was studied at B3LYP/6- 31C（d,p） level. For the model compound α-hydroxy epoxides, two possible reaction pathways Ⅰ and Ⅱ were calculated. The main difference is the order of ethylene release and six- to five-member ring rearrangement. The ring contraction rearrangement in pathway Ⅰ is the first step and this step is the rate controlling step with a free energy barrier of 116.62 kJ/mol. For pathway Ⅱ, the ethylene release occurs first, and is followed by a six-member ring opening reaction which is the rate controlling step, and the barrier is 251.38 kJ/mol. The reason for such high barrier is that the ethylene release results in the following reaction being more difficult. The results show that pathway Ⅰ （C-C rearrangement and then ethylene release） is more favorable, which is consistent with experimental results.

关键词： AIEt3 Rearrangement Density functional theory Diol Epoxide

Recent Progress in Donor-Acceptor Type Conjugated Polymers for Organic Field-effect Transistors

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Chinese Journal of Polymer Science 2023年第5期41卷 652-670,I0006页

作者： Yi-Fan Li Yun-Long guo Yun-qi Liu Beijing National Laboratory for Molecular Sciences Key Laboratory of Organic solidsInstitute of ChemistryChinese Academy of SciencesBeijing 100190China University of Chinese Academy of Sciences Beijing 100049China

The recent progress in the design and synthesis of high-performance donor-acceptor conjugated polymeric semiconducting materials is reviewed from the perspective of multiscale *** multiscale of conjugated polymers is from the primary one-dimensional polymer molecular scale to the secondary polymer-chains interaction scale,and then to the tertiary polymer aggregate *** review focuses on the design and synthesis of polymer molecules,proposes new classification rules,and rationally summarizes the design strategies and modulation methods of *** describe the recent progress from these three aspects:(1)the modification ofπ-conjugated backbone,(2)the evolution of the polymerization methods,and(3)the regulation of aggregate-state structure.

关键词： Conjugated polymers Donor-acceptor Organic field-effect transistors Multiscale optimization

Impact of undissociated volatile fatty acids on acidogenesis in a two-phase anaerobic system

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Journal of Environmental Sciences 2016年第4期28卷 196-201页

作者： Keke Xiao Yan zhou Chenghong guo Yogananda Maspolim Wun Jern ng Advanced Environmental Biotechnology Centre Nanyang Environment and Water Research InstituteNanyang Technological University School of Civil and Environmental Engineering Nanyang Technological University

This study investigated the degradation and production of volatile fatty acids（VFAs）in the acidogenic phase reactor of a two-phase anaerobic system.20 mmol/L bromoethanesulfonic acid（BESA）was used to inhibit acidogenic methanogens（which were present in the acidogenic phase reactor）from degrading *** impact of undissociated volatile fatty acids（un VFAs）on＂net＂VFAs production in the acidogenic phase reactor was then evaluated,with the exclusion of concurrent VFAs degradation.＂Net＂VFAs production from glucose degradation was partially inhibited at high un VFAs concentrations,with 59%,37% and 60% reduction in production rates at 2190 mg chemical oxygen demand（COD）/L undissociated acetic acid（un HAc）,2130 mg COD/L undissociated propionic acid（un HPr）and 2280 mg COD/L undissociated n-butyric acid（un HBu）,*** profile of VFAs produced further indicated that while an un VFA can primarily affect its own formation,there were also un VFAs that affected the formation of other VFAs.

关键词： Anaerobic process Waste treatment Substrate inhibition Undissociated volatile fatty acids Acidogenesis

In situ TiN-reinforced CoCr2FeNiTi(0.5) high-entropy alloy composite coating fabricated by laser cladding

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Rare Metals 2020年第10期39卷 1190-1195页

作者： Ya-Xiong guo qi-Bin Liu Xiao-Juan Shang College of Materials and Metallurgy Guizhou UniversityGuiyang 550025China Guizhou Province Key Laboratory of Materials Structure and Strength Guiyang 550025China

The fcc structural CoCr2 FeNiTi(0.5) high-entropy alloy(HEA) composite coating with TiN particles reinforced was acquired by laser cladding on the commercial904 L stainless *** results show that phase structure is mainly composed of fcc solid solution and TiN *** coating exhibits excellent structural stability below850℃.The microstructure consists of irregular dendrite and TiN *** electron microscopy(TEM) results reveal that the close-packed plane of fcc phase is(111) with interplanar spacing of ~ 0.208 *** interface between TiN and fcc matrix is *** the angle of boundary between dendrite and matrix is ~ 65°.The hardness and corrosion resistance of coating have much improvement compared with those of substrate.

关键词： TiN particle reinforced High-entropy alloy Semi-coherent interface Laser cladding

Anti-epidermal growth factor receptor monoclonal antibodies in metastatic colorectal cancer: A meta-analysis

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World Journal of Gastroenterology 2015年第14期21卷 4365-4372页

作者： qi-Bin Song qi Wang Wei-guo Hu Department of Oncology Renmin Hospital of Wuhan University

AIM: To investigate the correlation between Kirsten rat sarcoma viral oncogene homolog(KRAS) status and the therapeutic effects of anti-epidermal growth factor receptor(EGFR) monoclonal antibodies(Mo Abs) in metastatic colorectal cancer(m CRC).METHODS: Randomized controlled trials(RCTs) were identified and the association between KRAS mutation and clinical outcome in m CRC patients treated with anti-EGFR Mo Abs was *** RCTs wereincluded in this ***-free survival and overall survival were used to assess the strength of the relationship between KRAS mutation and clinical ***: In first-line treatment, survival benefit was confined to patients with wild-type *** regimens and angiogenesis inhibitor treatment influenced the results of the *** KRAS m CRC patients did not seem to benefit from oxaliplatin-based chemotherapy(PFS: HR = 0.88, 95%CI: 0.70-1.10; OS: HR = 0.93, 95%CI: 0.82-1.04).Clinical benefit in m CRC patients was limited to therapeutic regimens which included anti-EGFR Mo Abs and fluorouracil-based therapy(PFS: HR = 0.77, 95%CI: 0.69-0.86; OS: HR = 0.85, 95%CI: 0.75-0.95).When anti-EGFR Mo Abs were used as second- or further-line treatment, clinical benefit was still confined to patients with wild-type ***: KRAS status is a potential predictive marker of clinical benefit due to anti-EGFR Mo Ab therapy in m CRC patients.

关键词： Colorectal neoplasm Kirsten rat sarcoma viral onco