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Chinese Journal of Polymer Science 2013年第10期31卷 1352-1358页

作者： Dan-dan yuan Xu-fu Cai Department of Polymer Science and Materials State Key Laboratory of Polymer Materials Engineering Sichuan University

A novel flame retardant （DAPSiO）, containing silicon and nitrogen, was synthesized by using dichlorodiphenylsilane, γchloropropyl methyl dimethoxysilane and 1,2-ethanediamine. DAPSiO was used together with potassium-4-（phenylsulfonyl）benzenesulfonate （KSS） to prepare a flame-retardant system for polycarbonate （PC）. The structure of DAPSiO was characterized by Fourier transform infrared spectroscopy （FTIR）, and 1H-NMR tests. Flammability and thermal behaviors of PC/KSS/DAPSiO systems were estimated by limited oxygen index （LOI）, vertical burning test （UL-94） and thermogravimetric analysis （TGA） tests. The results showed that the flame retardancy and thermal stability of PC/KSS system were improved with the addition of DAPSiO. When 1 wt% DAPSiO and 0.5 wt% KSS were incorporated, the LOI value of PC was found to be 44, and class V-0 of UL-94 test was passed. The scanning electron microscopy （SEM） and FTIR indicated that PC/KSS/DAPSiO system held a more cohesive and denser char structure when compared with pure PC and PC/KSS system.

关键词： Flame retardant Thermal properties Silicon Polycarbonate.

Thermal Degradation Kinetics of N,N'-Di(diethoxythiophosphoryl)-1,4-phenylenediamine

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Chemical Research in Chinese Universities 2008年第5期24卷 628-631页

作者： ren yuan-lin CHENG Bo-wen ZHANG Jin-shu JIANG Ai-bing fu Wen-li School of Textile Tianjin Municipal Key Laboratory of Fiber Modification and functional Fiber Tianjin Polytechnic University Tianjin 300160 P. R. China

The non-isothermal degradation kinetics of N,N＇-di（diethoxythiophosphoryl）-1,4-phenylenediamine in N2 was studied by TG-DTG *** kinetic parameters,including the activation energy and pre-exponential factor of the degradation process for the title compound were calculated by means of the Kissinger and Flynn-Wall-Ozawa（FWO）method and the thermal degradation mechanism of the title compound was also studied with the Satava-Sestak *** results indicate that the activation energy and pre-exponential factor are 152.61 kJ/mol and 9.06×101 4s -1with the Kissinger method and 154.08 kJ/mol with the Flynn-Wall-Ozawa method,*** has been shown that the degradation of the title compound follows a kinetic model of one-dimensional diffusion or parabolic law,the kinetic function is G（α）=α2and the reaction order is n=2.

关键词： N,N'-Di(diethoxythiophosphoryl)-l,4-phenylenediamine Thermal degradation kinetics Activation energy Mechanism

Degradation of CTLA-4 balances toxicity and efficacy

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Science Bulletin 2019年第19期64卷 1388-1389页

作者： Zhenhua ren Yang-Xin fu The Department of Pathology UT Southwestern Medical CenterDallasTX75235-9072USA The Department of Immunology UT Southwestern Medical CenterDallasTX75235-9072USA

The notorious side effects of anti-CTLA-4 limit its use in the clinic,but what causes the severe side effects remains largely *** et al.[1]elucidated antibody-induced CTLA-4lysosomal degradation as a new mechanism accounting for the severe immunotherapy-related adverse effects and limited efficacy of anti-CTLA-4 ***-4 expresses on regulatory T cells(Tregs)and activated CD8 and CD4 effector cells.

关键词： Degradation CTLA-4 toxicity

Polymer types regulation strategy toward the synthesis of carbonized polymer dots with excitation-wavelength dependent or independent fluorescence

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Chinese Chemical Letters 2023年第2期34卷 388-392页

作者： Jianliang Bai Xinyu Wang Yaqing Zhu Guojun yuan Shuang Wu fu Qin Xu Yu Lili ren School of Chemistry&Chemical Engineering Southeast UniversityNanjing 211189China School of Environment and Chemical Engineering Anhui Vocational and Technical CollegeHefei 230011China

Three kinds of carbonized polymer dots(CPDs) synthesized via a one-pot process from ophenylenediamine(OPD), m-phenylenediamine(MPD) and p-phenylenediamine(PPD) exhibit excitationwavelength independent yellow, green and red emissions, respectively. In sharp contrast, two kinds of CPDs prepared via a hydrothermal process from citric acid(CA) and diethylenetriamine(DETA) exhibit obvious excitation-wavelength dependent emissions. Through the characterization and comparison of the two types of CPDs, it is concretely revealed that the polymer structure types during the formation of CPDs can effectively control the fluorescence excitation-wavelength independence/dependence. The homogeneous polymer structures contained in CPDs contribute to excitation-wavelength independence, whereas random copolymer structures contribute to excitation-wavelength dependence. These studies are of great significance for further understanding the polymer structures and designing unique optical properties of CPDs.

关键词： Carbonized polymer dots Excitation-wavelength dependence Excitation-wavelength independence Homogeneous polymer structures Random polymer structures

Microstructure and Mechanical Properties of High-Nitrogen Austenitic Stainless Steels Subjected to Equal-Channel Angular Pressing

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Acta Metallurgica Sinica(English Letters) 2016年第2期29卷 140-149,104页

作者： fu-yuan Dong Peng Zhang Jian-Chao Pang Qi-Qiang Duan Yi-Bin ren Ke Yang Zhe-Feng Zhang Shenyang National Laboratory for Materials Science Institute of Metal Research Chinese Academy of Sciences

Three high-nitrogen stainless steels with different N contents were successfully processed by equal-channel angular pressing for one pass, and their microstructures and mechanical properties were investigated. It was found that the microstructure of the billet was heterogeneous across the billet thickness, resulting in the difference in the mechanical properties due to the different deformation conditions. A relatively low strength, high uniform elongation, and high work- hardening rate for the samples at the bottom of the billet was achieved in comparison with those processed at the top. Meanwhile, it was observed that the density of deformation twins increased with the content of N; accordingly, the strength and elongation of the alloys increase with the content of N, resulting in a good strength-ductility combination.

关键词： High-nitrogen stainless (HNS) steels Equal-channel angular pressing (ECAP) N content Twinning Strength Ductility

ROP GTPase-mediated auxin signaling regulates pavement cell interdigitation in Arabidopsis thaliana

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Journal of Integrative Plant Biology 2015年第1期57卷 31-39页

作者： Deshu Lin Huibo ren Ying fu Center for Genomics and Biotechnology Fujian Agriculture and Forestry University State Key Laboratory of Plant Physiology and Biochemistry College of Biological Sciences China Agricultural University

In multicellular plant organs, cell shape formation depends on molecular switches to transduce developmental or environmental signals and to coordinate cell-to-cell communi- cation. Plants have a specific subfamily of the Rho GTPase family, usually called Rho of Plants （ROP）, which serve as a critical signal transducer involved in many cellular processes. In the last decade, important advances in the ROP-mediated regulation of plant cell morphogenesis have been made by using Arubidopsis thaliana leaf and cotyledon pavement cells. Especially, the auxin-ROP signaling networks have been demonstrated to control interdigitated growth of pavement ceils to form jigsaw-puzzle shapes. Here, we review findingsrelated to the discovery of this novel auxin-signaling mecha- nism at the cell surface. This signaling pathway is to a large extent independent of the well-known Transport Inhibitor Response （TIR）-Auxin Signaling F-Box （AFB） pathway, and instead requires Auxin Binding Protein 1 （ABP1） interaction with the plasma membrane-localized, transmembrane kinase （TMK） receptor-like kinase to regulate ROP proteins. Once activated, ROP influences cytoskeletal organization and inhibits endocytosis of the auxin transporter PINt. The present review focuses on ROP signaling and its self-organizing feature allowing ROP proteins to serve as a bustling signal decoder and integrator for plant cell morphogenesis.

关键词： Auxin leaf pavement cell Rho of plants GTPase

Intrinsic transverse relaxation mechanisms of polarized alkali atoms enclosed in radio-frequency magnetometer cell

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Chinese Physics B 2019年第9期28卷 385-390页

作者： Yang-Ying fu Jie yuan College of Advanced Interdisciplinary Studies National University of Defense Technology

The intrinsic transverse relaxation mechanisms of polarized alkali atoms enclosed in the radio-frequency magnetometer cell are *** intrinsic transverse relaxation rate of cesium atoms as a function of cell temperature is *** absorption of alkali atoms by the glass wall and the reservoir effect are the main error factors which contribute to the disagreements between theory and experiments.A modified relaxation model is presented, in which both the absorption of alkali atoms by the glass wall and the reservoir effect are *** study provides a more accurate description of the intrinsic transverse relaxation mechanisms of polarized alkali atoms, and enlightens the optimization of the cell design.

关键词： intrinsic transverse relaxation modified relaxation model absorption of alkali atoms reservoir effect

A tectono-thermal perspective on the petroleum generation,accumulation and preservation in the southern Ordos Basin, North China

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Petroleum Science 2024年第3期21卷 1459-1473页

作者： Peng Yang Zhan-Li ren Jin-Hua fu Hong-Ping Bao Hui Xiao Zheng Shi Kun Wang yuan-yuan Zhang Wen-Hui Liu Wen-Hou Li State Key Laboratory of Continental Dynamics Department of GeologyNorthwest UniversityXi'an710069ShanxiChina National Engineering Laboratory for Exploration and Development of Low-Permeability Oil and Gas Fields Exploration and Development Research Institute of PetroChina Changqing Oilfield CompanyXi'an710018ShaanxiChina Shaanxi Key Lab of Petroleum Accumulation Geology School of Earth Science and EngineeringXi'an Shiyou UniversityXian710065ShaanxiChina Wuxi Research Institute of Petroleum Geology Petroleum Exploration and Production Research InstituteSINOPECWuxi214126JiangsuChina

The southern Ordos Basin has excellent petroleum exploration ***,the tectono-thermal history and the controls on petroleum generation,accumulation and preservation conditions in southern basin are *** this study,we analyzed the present geothermal field,paleo-geothermal gradient,maturity of the hydrocarbon source rocks,uplift and cooling process and tectono-thermal evolution *** the study area,for the Ordovician,Permain and the Triassic strata,the present temperature is low(3070℃)in the southeastern area but high(80140℃)in the northwestern *** paleogeothermal gradient varied from 24℃/km to 30℃/km with a heat flow of 58—69 m W/m^(2)(i.e.,a medium-temperature basin).The paleo-temperatures are higher than the present temperatures and the maximum paleo-temperatures controlled the thermal maturity of the source *** vitrinite reflectance(Ro)values of the Triassic strata are>0.7%and the thermal maturity reached the middlemature oil generation *** Rovalues of the Permian-Ordovician strata are>1.8%and the thermal maturity reached the over-mature gas generation *** southern Ordos Basin has experienced the multiple tectonic events at the Late Ordovician Caledonian(452 Ma),Late Triassic(215 Ma),Late Jurassic(165160 Ma),End-Early Cretaceous(110100 Ma)and Cenozoic(since 40 Ma).A large-scale tectonothermal event occurred at the End-Early Cretaceous(110100 Ma),which was controlled by lithospheric extension,destruction and *** event led to the highest paleo-temperatures and thermal maturities and coeval with the peak period of petroleum generation and *** southern Ordos Basin has undergone rapid and large-scale uplift since the Late Cretaceous due to expansion of the northeastern margin of the Tibetan Plateau,uplift of the Qinling orogenic belt and thrust faulting in the Liupanshan tectonic *** southern Ordos Basin experienced tectonic overprinting that was strong in the south and weak in the *** str

关键词： Fission-track dating Vitrinitereflectance Geothermal field Tectono-thermal evolution Petroleum geology Ordos Basin

Boosting multi-features with prior knowledge for mini unmanned helicopter landmark detection

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2008年第2期9卷 256-261页

作者： Qin-yuan ren Ping LI Bo HAN The State Key Laboratory of Industrial Control Technology Zhejiang University Hangzhou 310027 China

Without sufficient real training data,the data driven classification algorithms based on boosting method cannot solely be utilized to applications such as the mini unmanned helicopter landmark image *** this paper,we propose an approach which uses a boosting algorithm with the prior knowledge for the mini unmanned helicopter landmark image *** stage forward stagewise additive model of boosting is analyzed,and the approach how to combine it with the prior knowledge model is *** approach is then applied to landmark image detection,where the multi-features are boosted to solve a series of problems,such as rotation,noises affected,*** of real flight experiments demonstrate that for small training examples the boosted learning system using prior knowledge is dramatically better than the one driven by data only.

关键词： Boosting Prior knowledge model Landmark detection

Effects of welding wire composition and welding process on the weld metal toughness of submerged arc welded pipeline steel

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International Journal of Minerals,Metallurgy and Materials 2009年第1期16卷 65-70页

作者： De-liang ren fu-ren Xiao Peng Tian Xu Wang Bo Liao Key Lab of Metastable Materials Science ＆ Technology and College of Materials Science ＆ Engineering Yanshan University Qinhuangdao 066004 China Department of Materials Science and Engineering Shijiazhuang Railway Institute Shijiazhuang 050043 China Steel Pipe Works of North China Petroleum Qing County 062658 China

The effects of alloying elements in welding wires and submerged arc welding process on the microstructures and low-temperature impact toughness of weld metals have been investigated. The results indicate that the optimal contents of alloying elements in welding wires can improve the low-temperature impact toughness of weld metals because the proeutectoid ferrite and bainite formations can be suppressed, and the fraction of acicular ferrite increases. However, the contents of alloying elements need to vary along with the welding heat input. With the increase in welding heat input, the contents of alloying elements in welding wires need to be increased accordingly. The microstructures mainly consisting of acicular ferrite can be obtained in weld metals after four-wire submerged arc welding using the wires with a low carbon content and appropriate contents of Mn, Mo, Ti-B, Cu, Ni, and RE, resulting in the high low-temperature impact toughness of weld metals.

关键词： pipeline steel welding wire submerged arc welding impact toughness acicular ferrite welding heat input