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Precise evaluation of h→cc and axion-like particle production

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Chinese Physics C 2021年第9期45卷 65-72页

作者： Shi-Yuan li zhen-Yang li Peng-Cheng Lu zong-Guo Si School of Physics Shandong UniversityJinan 250100China

We study the decay of the SM Higgs boson to a massive charm quark pair at the next-to-next-to-leading order QCD and next-to-leading order *** the second order of QCD coupling,we consider the exact calculation of flavour-singlet contributions where the Higgs boson couples to the internal top and bottom *** information on the running mass effects related to Yukawa coupling may be obtained by analyzing this *** precision production for h→cc within the SM makes it possible to search for new physics that may induce relatively large interactions related to the charm *** an example,we evaluate the axion-like particle associate production with a charm quark pair in the Higgs decay and obtain some constraints for the corresponding parameters under some assumptions.

关键词： Higgs boson charm quark QCD axion-like particle

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基于耦合映像格子的明文关联图像加密方案

聊城大学学报（自然科学版） 2025年第1期38卷 14-22页

作者：张爽李震贵阳人文科技学院大数据与信息工程学院贵州贵阳550025 贵州大学大数据与信息工程学院贵州贵阳550025

明文敏感性是图像加密系统重要的性能指标,用来评估加密系统抵抗差分攻击能力,而明文关联是提高明文敏感性的主要手段。针对明文关联问题,提出一种基于耦合映像格子(CML)的明文关联图像加密方案。该方案首先构建明文关联内部密钥生成模... 详细信息

明文敏感性是图像加密系统重要的性能指标,用来评估加密系统抵抗差分攻击能力,而明文关联是提高明文敏感性的主要手段。针对明文关联问题,提出一种基于耦合映像格子(CML)的明文关联图像加密方案。该方案首先构建明文关联内部密钥生成模型生成明文关联密钥流,然后在密钥流控制下完成加密操作。加密算法首先采用一轮Zigzag置乱和XOR掩码,然后进行Zigzag-CBC扩散,最后再进行一轮Zigzag置乱和XOR掩码输出密文图像。随后采用直方图、相关性分析、差分攻击、信息熵等方法对密码系统进行安全性能分析,实验结果表明,基于耦合映像格子的明文关联图像加密方案具有良好的安全性能,可以满足绝大多数应用场景下的图像加密需求。

关键词：图像加密安全性分析耦合映像格子

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全氟和多氟烷基磺酸的研究 Ⅳ.3-氧杂多氟烷烃磺酸酯的合成及其硫-氧和碳-氧键的断裂

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化学学报 1982年第4期 337-352页

作者：陈庆云朱蓉仙李宗珍王珊娣黄维垣中国科学院上海有机化学研究所

以3-氧杂多氟烷烃磺酰氟XOCF2CF2SO2F为原料,在二氯甲烷中于-20～-30C°与三乙胺、含氟醇或苯酚反应得到一系列氧杂多氟磺酸酯XOCF2CF2SO3R（1a～1g）,产率52～90％.影响产率的主要因素是反应温度,而不是碱用量.亲核试剂与这些磺酸酯作... 详细信息

以3-氧杂多氟烷烃磺酰氟XOCF2CF2SO2F为原料,在二氯甲烷中于-20～-30C°与三乙胺、含氟醇或苯酚反应得到一系列氧杂多氟磺酸酯XOCF2CF2SO3R（1a～1g）,产率52～90％.影响产率的主要因素是反应温度,而不是碱用量.亲核试剂与这些磺酸酯作用,主要引起酯基的C—O断裂.如1a或1c与I,CNS和R1R2NH反应得HCF2CF2CH2Y（Y=I,CNS,R1R2N）,与HCF2CF2CH2O得对称醚（HCF2CF2CH2）2O.与前人不同的是C2H5O,CH3OCH2CH2O和C6H5O对1a或1c都以C—O断裂为主,而1f与HCF2CF2CH2O的反应似乎是发生了S—O断裂.首次研究了氟碳烷氧基阴离子RFCF2O[FO2SCF2CF2O,（CF3）2CFO,n-C3F7OCF（CF3）CF2O,FO2SCF2CF2OC2CF2O和Cl（CF2）5CF2O]对1a和1c的亲核取代,所得产物的结构与RFCOF+F→←RFCF2O平衡中RFCF2O的生成量和溶解度有关.在HMPA中为均相反应,产物以RFCF2OCH2CF2CF2H为主;在DMSO中反应液和固体不互溶,羧酸酯为主要产物;若以DMF为溶剂,则可以是酯亦可以是醚;以DG为溶剂时,虽然混合液体不互溶,但仍以C—O断裂为主.可能的解释是在高介电常数的非质子性溶剂中（如DMSO,DMF）,溶剂参与了反应,促使磺酸酯发生S—O断裂,生成的OCH2R’与酰氟作用而得酯.由于DG的低介电常数,亲核试剂仍以引起C—O断裂为主而得醚.当无氟化钾时,1a或1c在DG中并不与RFCOF反应,但在DMSO,DMF,HMPA中却得酯,也符合于溶剂效应的假设,即溶剂参与反应,促使磺酸酯发生S—O断裂,生成的HCF2CF2CH2O再与酰氟发生酯化.全氟α-正丙氧基丙酸钠在DMSO,DMF,DG中或其酸在DMSO中亦均能与1a成酯.估计其机理不同于以RFCOF为原料者,前者是简单的亲核取代,而后者可能是溶剂参与了反应,因为全氟羧酰氟与氟化钾在DMSO作用下,得不到相应的羧酸阴离子.

关键词：全氟氟烷烃氟化钾氟化物杂多磺酸酯亲核试剂类阴离子试剂 HMPA 氟离子阴离子产率 CFO 反应时 DMSO 亚砜反应温度 OCF 烷氧基二乙二醇二甲醚丙氧基对甲苯磺酸氟烷基

Molecular imprinting of protein by coordinate interaction

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Chinese Chemical Letters 2009年第6期20卷 747-750页

作者： Jun Wang zhen Dong Hua Zhi Yong Chen Yuan zong li Mei Ping Zhao The Key Laboratory of Bioorganic Chemistry and Molecular Engineering College of Chemistry and Molecular Engineering Peking University Beijing 100871 China

In this article, a novel strong interaction by forming complex between bovine serum albumin （BSA） and copper ion was utilized for the preparation of molecular imprinted bydrogel in aqueous solution. Results show that the inclusion of copper ion in preparation can bridge the template BSA and functional monomers together and improve the imprinting effect compared to the polymer made without copper ion added. High selectivity factor and large adsorption capacity are also observed for the obtained BSA-imprinted hydrogel.

关键词： Molecular imprinted hydrogel Bovine serum albumin Copper ion

全程化药学服务干预社区慢性阻塞性肺疾病患者病情分析

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中华全科医学 2010年第12期8卷 1561-1563页

作者：李真方宗君葛明建杨容祝娅上海市宝山区张庙街道长江路社区卫生服务中心 200431

目的采用全程化药学服务对社区慢性阻塞性肺疾病(chromic obstructive pulmonary disease,COPD)患者进行干预,倡导合理用药、改善病情、提高生存质量。方法将社区确诊为COPD的150例患者随机分为干预组(A组)79例,对照组(B组)71例,A组采... 详细信息

目的采用全程化药学服务对社区慢性阻塞性肺疾病(chromic obstructive pulmonary disease,COPD)患者进行干预,倡导合理用药、改善病情、提高生存质量。方法将社区确诊为COPD的150例患者随机分为干预组(A组)79例,对照组(B组)71例,A组采用全程化药学干预方法。B组不施行干预措施。结果干预后显示A组呼吸专科药理知识成绩显著提高,B组干预前后无明显变化;药物治疗作用和副作用总知晓率A组高于B组;A组症状、体征、6分钟行走距离(6MWD)、膈肌移动度(DM)、常规肺功能部分指标等较B组改善明显(P<0.05);生存质量(QOL)调查提示A组QOL总分、总均分、生活能力、社会交往等评估优于B组,差异均有统计学意义(t=2.624、P=0.010,t=2.633、P=0.009,t=5.960、P=0.000,t=3.785、P=0.000);A组年就诊数、年住院率和年治疗费用支出分别降低,与B组相比差异均有统计学意义(P<0.05),成本-效果分析表明A组优于B组。结论社区全程化药学服务可改善COPD患者病情和提高生存质量。

关键词：肺疾病阻塞性社区药学

AIE probes towards biomolecules: the improved selectivity with the aid of graphene oxide

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Science China Chemistry 2015年第12期58卷 1800-1809页

作者： Qianqian li zhen li Hubei Key Laboratory on Organic and Polymeric Opto-Electronic Materials

Fluorescence probes with aggregation-induced emission(AIE) property have attracted much research interest and have been identified as novel fluorescence biosensors with "turn-on" response. In this mini review, we present an overview of the recent work on improving the selectivity of AIE biosensors with the aid of graphene oxide(GO), according to the displacement strategy.

关键词： aggregation-induced emission biosensor selectivity graphene oxide displacement strategy

In Vitro Study on Mg-Sn-Mn Alloy as Biodegradable Metals

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Journal of Materials Science & Technology 2014年第7期30卷 675-685页

作者： zhen zhen Tingfei Xi Yufeng zheng li li Lugee li Center for Biomedical Materials and Tissue Engineering Academy for Advanced Interdisciplinary StudiesPeking University Biomedical Engineering Research Center Shenzhen InstitutePeking University Department of Materials Science and Engineering College of EngineeringPeking University Center for Biomedical Materials and Engineering Harbin Engineering University Dongguan EONTEC Company Ltd

The mechanical properties, chemical properties and biocompatibility of Mg-3Sn-0.5Mn alloy were tested. A series of in vitro evaluations such as tensile test, static and dynamic immersion test, hemocompatibility test as well as cytotoxicity test were presented, with commercial magnesium alloy WE43 as the control. Mg-3Sn-0.5Mn alloy possesses suitable strength and superior ductility compared with WE43 and AZ31. Static immersion and dynamic degradation tests showed more uniform degradation with a more moderate rate for Mg-3Sn-0.5Mn alloy （0.34 mm/y in static condition and 0.25 mm/y in dynamic condition） compared with WE43 alloy （0.42 mm/y in static condition and 0.33 mm/y in dynamic condition） in Hank＇s solution. Blood compatibility evaluation suggested that Mg-3Sn-0.5Mn alloy had no destructive effect on erythrocyte and showed excellent anti-thrombogenicity to blood system. Besides, Mg-3Sn-0.5Mn alloy showed no inhibition effect to L929 metabolic activity and mild toxicity to vascular smooth muscle cell （VSMC） in preliminary cell viability assessment. By considering its excellent mechanical strength, corrosion resistance, low ion release rate and good biocompatibility, Mg-3Sn-0.5Mn alloy may be a promising economical candidate as biomedical implant material for load-bearing clinical applications in the future.

关键词： Mg-3Sn-0.5Mn alloy Corrosion Dynamic immersion Static immersion Biodegradable material

Self-assembly of liposomes Loading Hinesol by Rapid Expansion from Supercritical to Surfactant Solution

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Chemical Research in Chinese Universities 2010年第4期26卷 617-621页

作者： WEN zhen YOU Xin-kui liU Bo zhenG zong-kun PU Yi-tao li Qiong School of Chemistry and Chemical Engineering Shenzhen University Shenzhen 518060 P. R. China School of Chemistry and Chemical Engineering South China University of Technology Guangzhou 510640 P. R. China

To improve the encapsulation efficiency and minimize particle agglomeration of liposomes, rapid expansion from supercritical to surfactant solution（RESSS） was applied to self-assembly of liposomes entrapping hinesol in supercritical carbon dioxide（SC-CO2） medium. In the process, the solution of liposomal materials and hinesol dissolved in the mixture of SC-CO2/ethanol was sprayed into a surfactant solution. The surfactant provided stabilization for liposomes by preventing bubbles overflowing and liposomes agglomeration during the spraying process. The encapsulating performance and particle size distribution of liposomes could be controlled by changing expansion processing conditions. When the solution was sprayed into a 5.0% Poloxamer 188 solution at a flow rate of 2 L/min, the entrapment efficiency and average particle size of liposomes were found to be 88.26% and 124 nm, respectively, which came to the standards of Chinese pharmacopoeia. The results show RESSS process provides an innovative method for formation of liposomes incorporating valid compositions extracted from the Chinese traditional medicines in SC-CO2 medium.

关键词： liposome Hinesol Supercritical carbon dioxide Rapid expansion Surfactant

Stochastic Optimal Control Problem in Advertising Model with Delay

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Journal of Systems Science & Complexity 2020年第4期33卷 968-987页

作者： CHEN li WU zhen School of Science China University of Mining&TechnologyBeijing 100083China School of Mathematics Shandong UniversityJinan 250100China

This paper investigates the optimal control problem arising in advertising model with delay. The authors reformulate the problem in Hilbert space by stochastic evolution equation and consider the optimal control problem of controlled stochastic evolution system. The necessary and sufficient optimality conditions of the control are established. The proposed approach is different from most existing studies of optimal advertising policy problem with delay. These results are applied to the optimal advertising policy problem under two different structures and the optimal advertising strategies are obtained.

关键词： optimal stochastic Optimal