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Photocatalytic dicarboxylation of strained C-C bonds with CO_(2) via consecutive visible-light-induced electron transfer

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Chinese Chemical Letters 2024年第6期35卷 268-273页

作者： Yi Liu zhe-hao wang Guan-Hua Xue Lin Chen Li-Hua Yuan Yi-Wen Li Da-Gang Yu Jian-Heng Ye Key Laboratory of Green Chemistry&Technology of Ministry of Education College of ChemistrySichuan UniversityChengdu 610064China College of Polymer Science and Engineering State Key Laboratory of Polymer Materials EngineeringSichuan UniversityChengdu 610065China State Key Laboratory of Elemento-Organic Chemistry Nankai UniversityTianjin 300071China

Dicarboxylic acids have a wide range of applications in the polymer industry to construct valuable *** has recently emerged as an efficient and sustainable strategy to generate dicarboxylic ***,photocatalytic dicarboxylation with CO_(2) is mainly limited to unsaturated bonds,and the dicarboxylation of C-C single bonds still remains a ***,we report a photocatalytic dicarboxylation of C-C single bonds in strained rings with CO_(2) units via consecutive photo-induced electron transfer(ConPET).It is also the first photocatalytic reductive ring-opening reaction of ***,this transition-metal-free protocol exhibits good functional group tolerance,broad substrate scope,facile scalability,and easy product ***,diacids can easily be derivatized to mainchain liquid crystalline polyesters.

关键词： Consecutive photo-induced electron transfer Visible-light catalysis Dicarboxylation Carbon dioxide Cyclopropanes

液固两相流对A182F347不锈钢材料的磨损特性

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煤炭学报 2016年第11期41卷 2883-2888页

作者：偶国富刘旭金浩哲王超浙江理工大学多相流沉积-冲蚀试验室浙江杭州310018

以直径为150μm的Si O2和Al2O3混合物为磨料,在自制的旋转式液-固两相流冲蚀试验装置上研究冲击角度、冲击速度及浆体浓度对奥氏体不锈钢A182F347的冲蚀规律,结合试件表面的冲蚀形貌分析,揭示稀相液固两相流体系下奥氏体不锈钢A182F347... 详细信息

以直径为150μm的Si O2和Al2O3混合物为磨料,在自制的旋转式液-固两相流冲蚀试验装置上研究冲击角度、冲击速度及浆体浓度对奥氏体不锈钢A182F347的冲蚀规律,结合试件表面的冲蚀形貌分析,揭示稀相液固两相流体系下奥氏体不锈钢A182F347冲蚀机理。结果表明：4%~8%的浆体浓度下,冲击角度对试件的冲蚀规律近似,即在冲击角度为60°时出现磨损率峰值,峰值两侧区域磨损率逐渐降低;浆体浓度为6%,冲击速度从1.65 m/s增加至3.85 m/s时,试件磨损率呈指数增加;在高流速下,冲击角度为60°,浆体浓度小于6%时,试件磨损率受浆体浓度的影响较小,浆体浓度大于6%时,浓度越高,试件磨损率越大。在低流速下,浆体浓度大于8%时,试件磨损率受浆体浓度影响较小;A182F347的冲蚀磨损在低冲击角度下,以犁沟切削磨损为主,在高冲击角度下,以锻打变形磨损为主。建立的数学模型与试验结果较吻合。

关键词：液固两相流不锈钢A182F347 冲蚀磨损犁沟切削变形磨损

后股权分置时代的并购支付方式——国际经验与中国借鉴

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特区经济 2011年第11期 130-132页

作者：王哲王浩林百宏华南农业大学经管学院广东广州510642 厦门大学管理学院福建厦门361005

本文回顾了最近几年国外对并购支付方式的实证研究成果,同时从美国、欧洲和全球不同地区分析国外主要采用的并购支付方式。我们发现,与成熟证券市场的国家相比,目前我国支付手段过于单一,普遍采用现金支付;股票支付将逐渐成为我国后股... 详细信息

本文回顾了最近几年国外对并购支付方式的实证研究成果,同时从美国、欧洲和全球不同地区分析国外主要采用的并购支付方式。我们发现,与成熟证券市场的国家相比,目前我国支付手段过于单一,普遍采用现金支付;股票支付将逐渐成为我国后股权分置时代并购支付的主要手段。通过以上分析,我们为相关部门提供了翔实而全面的国际经验,并在最后提出相应建议。

关键词：后股权分置并购支付方式

闽北海域水体中溶解有机碳的时空变化及其影响因素

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海洋环境科学 2018年第2期37卷 245-251页

作者：丰卫华钱健郝喆王志富许恒韬张冬融国家海洋局第二海洋研究所工程海洋学重点实验室浙江杭州310012

为探讨闽北海域水体中溶解有机碳(DOC)时空变化特征及其主要影响因素,于2015年8月、11月、2016年2月和5月对闽北海域环境进行调查,分析该海域DOC时空分布特征,并探讨DOC分布与Chl a、COD、AOU、营养盐、盐度等环境因子的关系。结果表明:... 详细信息

为探讨闽北海域水体中溶解有机碳(DOC)时空变化特征及其主要影响因素,于2015年8月、11月、2016年2月和5月对闽北海域环境进行调查,分析该海域DOC时空分布特征,并探讨DOC分布与Chl a、COD、AOU、营养盐、盐度等环境因子的关系。结果表明:2015~2016年闽北海域DOC的含量范围为0.32~2.78 mg/L,均值为1.19 mg/L;季节变化上,秋季>夏季>冬季>春季;空间分布上,整体呈现由近岸向远岸逐渐降低,由南向北逐渐升高的变化趋势,各季节略有差异。DOC与Chl a、COD以及盐度有较强的相关性,与AOU和营养盐的相关性不显著,不同季节影响DOC分布的主要环境因素存在一定差异。研究海域水体中DOC主要受浮游植物光合作用、陆地径流等因素影响,不同季节主要环境因素具有一定差异。

关键词：闽北海域溶解有机碳时空分布环境因子

Synthesis and cationic selectivity studies of novel calix[4]arene derivatives containing heteroatom at the lower rim

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Science China Chemistry 2007年第5期50卷 654-659页

作者： wang hao LI zhe LIU Yu State Key Laboratory of Elemento-Organic Chemistry Department of Chemistry Nankai University Tianjin 300071 China State Key Laboratory of Elemento-Organic Chemistry Department of Chemistry Nankai University Tianjin 300071 China State Key Laboratory of Elemento-Organic Chemistry Department of Chemistry Nankai University Tianjin 300071 China

A series of calixarene derivatives 2―5 containing heteroatom at the lower rim have been synthesized. 1H NMR studies and crystallographic structures demonstrated that the calix[4]arene derivatives adopted cone conformations. Their cationic binding abilities and selectivities towards heavy and tran- sition metal ions have been evaluated by solvent extraction of aqueous metal picrates. The obtained results indicated that the introduction of nitrogen, sulfur, and/or phosphor atoms to the calix[4]arene framework could effectively enhance their binding ability and selectivity for heavy and transition metal ions, such as Pb2+ or Ag+.

关键词： calixarene, synthesis, cationic selectivity, solvent extraction

Identity-based aggregate signcryption in the standard model from multilinear maps

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Frontiers of Computer Science 2016年第4期10卷 741-754页

作者： hao wang zhen LIU zhe LIU Duncan S. WONG School of Information Science and Engineering Shandong Normal University Jinan 250014 China Shandong Provincial Key Labe ratory for Novel Distributed Computer Software Technology Jinan 250014 China Security and Data Sciences Hong Kong Applied Science and Technology Research Institute (ASTRI) Hong Kong China Laboratory of Algorithmics Cryptology and Security (LACS) University of Luxembourg Luxembourg L-1359 Luxembourg

Signcryption is a public key cryptographic method that achieves unforgeability and confidentiality simultaneously with significantly smaller overhead than that required by ＂digital signature followed by public key encryption＂. It does this by signing and *** a message in a single step. An aggregate signcryption scheme allows individual signcryption ciphertexts intended for the same recipi- ent to be aggregated into a single （shorter） combined ciphertext without losing any of the security guarantees. We present an aggregate signcryption scheme in the identity-based setting using multilinear maps, and provide a proof of security in the standard model. To the best of our knowledge, our new scheme is the first aggregate signcryption scheme that is secure in the standard model.

关键词： identity-based aggregate signcryption multilinear maps standard model GGH framework

Effects of Interface on the Dynamic Hysteresis Loss and Static Mechanical Properties of Illite Filled SBR Composites

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Chinese Journal of Polymer Science 2022年第11期40卷 1493-1502页

作者： zhe-Peng wang hao Zhang Qiang Liu Shao-Juan wang Shou-Ke Yan Key Laboratory of Rubber-Plastics Ministry of EducationQingdao University of Science&TechnologyQingdao266042China State Key Laboratory of Chemical Resource Engineering Beijing University of Chemical TechnologyBeijing100029China

Despite growing interest in nano-sized fillers,micro-sized fillers with desired compatibility are still used for reinforcing rubbers,owing to their lower production cost and easier processing relative to nano-sized ***,the abundant and eco-friendly clay minerals are recognized as the materials of the twenty-first ***,illite,a naturally occurring clay having dimension in micrometric scale,has been selected as filler to reinforce the *** improve the compatibility of illite with SBR,the illite was modified by either bis[3-(triethoxysilyl)propyl]tetrasulfide(Si69-illite)or 3-mercaptopropyltriethoxysilane(KH580-illite).The interfacial interactions of SBR composites filled with pristine illite(illite/SBR)and Si69-illite(Si69-illite/SBR),or KH580-illite(KH580-illite/SBR)were characterized by bound rubber content and Payne effect measurements,while dynamic hysteresis losses of these uncured and cured composites were also analyzed under various strain *** was found that the filler-rubber interactions were greatly improved for Si69-illite/SBR and KH580-illite/SBR systems compared to the illite/SBR *** leads to an increment of modulus at 300%strain of the composites from 3.46 MPa for illite/SBR to 7.70 MPa for Si69-illite/SBR and12.96 MPa for KH580-illite/***,lower rolling resistance and better wear resistance without compromising wet traction of Si69-illite/SBR and KH580-illite/SBR have been *** demonstrates the high possibility of Si69 and KH580 modified illites as promising alternative fillers for reinforcing rubbers.

关键词： Illite SBR Composite Dynamic hysteresis loss Static mechanical properties

Far-from-equilibrium electrosynthesis ramifies high-entropy alloy for alkaline hydrogen evolution

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Journal of Materials Science & Technology 2023年第35期166卷 234-240页

作者： Yunan wang hao Yang zhe Zhang Xiangying Meng Tao Cheng Gaowu Qin Song Li Key Lab for Anisotropy and Texture of Materials(MoE) School of Material Science and EngineeringNortheastern UniversityShenyang 110819China Institute of Functional Nano&Soft Materials(FUNSOM) Jiangsu Key Laboratory for Carbon-Based Functional Materials&DevicesSoochow UniversitySuzhou 215123China Jiangsu Key Laboratory of Advanced Negative Carbon Technologies Soochow UniversitySuzhou 215123China Institute of Materials Intelligent Technology Liaoning Academy of MaterialsShenyang 110004China

High-entropy alloys(HEAs)provide an ideal platform for developing highly active electrocatalysts and investigating the synergy of mixed ***-from-equilibrium synthesis holds great potential for fabricating HEAs at the nanoscale by rapidly shifting the thermodynamic conditions and manipulat-ing the growth *** far-from-equilibrium synthesis of nanomaterials has been successful un-der thermochemical conditions,it is markedly challenging under electrochemical environments,as the use of an electrolyte limits the accessible temperature window and the temporal tunability of ***,we demonstrate that applying a large electrochemical overpotential would create a far-from-equilibrium condition as changing the temperature of the system by considering the equation △G=△H−T△S+nF△ψ.An electrochemical far-from-equilibrium approach is thus setup for construct-ing hierarchical and self-supporting high-entropy alloy *** large overpotential drives the simultaneous reduction of multiple cations and the subsequent formation of a single-phase *** a proof-of-concept,hierarchical Fe_(0.22)Co_(0.18)Ni_(0.18)Cr_(0.14)Cu_(0.28)was fabricated and used as an electrocatalyst for the hydrogen evolution reaction in alkaline *** noble-metal-free HEA exhibits an overpoten-tial of 84 mV at a current density of 10 mA cm^(-2),which is among the lowest even compared to noble metal-based *** work opens a new avenue for building a variety of HEAs for energy and catalysis applications.

关键词： High-entropy alloys Nanostructures Electrocatalysis Hydrogen evolution reaction Far-from-equilibrium synthesis

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Twin cogenesis

Communications in Theoretical Physics 2023年第4期75卷 34-49页

作者： Wan-zhe Feng Jiang-hao Yu Center for Joint Quantum Studies and Department of Physics School of ScienceTianjin UniversityTianjin 300350China Institute of Theoretical Physics Chinese Academy of SciencesBeijing 100190China School of Physical Sciences University of Chinese Academy of SciencesBeijing 100049China

We investigate a cogenesis mechanism within the twin Higgs setup that can naturally explain the nature of dark matter,the cosmic coincidence puzzle,little hierarchy problem,leptogenesis,and the tiny neutrino *** heavy Majorana neutrinos are introduced to the standard model sector and the twin sector respectively,which explain the tiny neutrino masses and generate the lepton asymmetry and the twin lepton asymmetry at the same *** twin cogenesis mechanism applies to any viable twin Higgs model without an explicit Z_(2)breaking in the leptonic sector and evading theΔN_(eff) *** illustrate the twin cogenesis mechanism using the neutrino-philic twin two Higgs doublet model,a newly proposed model to lift the twin neutrino masses with spontaneous Z_(2)*** dark photon with a Stueckelberg mass O(10)MeV ensures the energy in the twin sector as well as the symmetric component of twin sector particles can be *** lightest twin baryons are the dark matter candidates with masses of approximately 5.5 GeV,which explains naturally the amount of dark matter and visible matter in the Universe are of the same *** also demonstrate twin cogenesis in the fraternal twin Higgs setup,in which the dark matter candidate is the twin bottom bound stateΩ’_(b’b’b’).

关键词： cogenesis cosmic coincidence asymmetric dark matter leptogenesis neutrino mass