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Alkylsulfonium salts for the photochemical desulphurizative functionalization of heteroarenes

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Organic Chemistry Frontiers 2022年第2期9卷 347-355页

作者： Xiaolong zhu Min jiang Xuan Li Enjie zhu Qirong deng Xiuyan Song jian Lv Daoshan Yang Key Laboratory of Optic-electric Sensing and Analytical Chemistry for Life Science MOECollege of Chemistry and Molecular EngineeringQingdao University of Science and TechnologyQingdao266042P.R.China Key Laboratory of Bioorganic Phosphorus Chemistry and Chemical Biology(Ministry of Education) Department of ChemistryTsinghua UniversityBeijing 100084People’s Republic of China College of Materials Chemistry and Chemical EngineeringHangzhou Normal UniversityHangzhou310036P.R.China

The development of new versatile alkylation reagents that can be transformed from diverse available chemical raw materials is highly ***,an efficient,metal-free organic photoredox-catalyzed direct alkylation of heteroarenes via a desulphurization strategy using alkylsulfonium salts as alkylation reagents under mild conditions has been described for the first *** inexpensive and efficient organic photoredox-catalyzed method offers a new and useful strategy for constructing various biologically interesting heteroarenes in the fields of synthetic and pharmaceutical chemistry,and extends the scope of the still limited sulfonium salt photochemistry.

关键词： salts alkylation sulfo

Closed-loop scheduling optimization strategy based on particle swarm optimization with niche technology and soft sensor method of attributes-applied to gasoline blending process

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Chinese Journal of Chemical Engineering 2023年第9期61卷 43-57页

作者： jian Long Kai deng Renchu He Key Laboratory of Smart Manufacturing in Energy Chemical Process Ministry of EducationEast China University of Science and TechnologyShanghaiChina Engineering Research Center of Process System Engineering Ministry of EducationEast China University of Science and TechnologyShanghai 200237China

Gasoline blending scheduling optimization can bring significant economic and efficient benefits to ***,the optimization model is complex and difficult to build,which is a typical mixed integer nonlinear programming(MINLP)*** the large scale of the MINLP model,in order to improve the efficiency of the solution,the mixed integer linear programming-nonlinear programming(MILP-NLP)strategy is used to solve the *** paper uses the linear blending rules plus the blending effect correction to build the gasoline blending model,and a relaxed MILP model is constructed on this *** particle swarm optimization algorithm with niche technology(NPSO)is proposed to optimize the solution,and the high-precision soft-sensor method is used to calculate the deviation of gasoline attributes,the blending effect is dynamically corrected to ensure the accuracy of the blending effect and optimization results,thus forming a prediction-verification-reprediction closed-loop scheduling optimization strategy suitable for engineering *** optimization result of the MILP model provides a good initial *** fixing the integer variables to the MILPoptimal value,the approximate MINLP optimal solution can be obtained through a NLP *** above solution strategy has been successfully applied to the actual gasoline production case of a refinery(3.5 million tons per year),and the results show that the strategy is effective and *** optimization results based on the closed-loop scheduling optimization strategy have higher *** with the standard particle swarm optimization algorithm,NPSO algorithm improves the optimization ability and efficiency to a certain extent,effectively reduces the blending cost while ensuring the convergence speed.

关键词： Blend Optimization algorithm Neural networks Particle swarm optimization Mixed integer programming

Steady Ricci solitons with horizontally ε-pinched Ricci curvature

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Science China Mathematics 2021年第7期64卷 1411-1428页

作者： Yuxing deng Xiaohua zhu School of Mathematics and Statistics Beijing Institute of TechnologyBeijing 100081China School of Mathematical Sciences and Beijing International Center for Mathematical Research Peking UniversityBeijing 100871China

In this paper,we prove that anyκ-noncollapsed gradient steady Ricci soliton with nonnegative curvature operator and horizontallyκ-pinched Ricci curvature must be rotationally *** an application,we show that anyκ-noncollapsed gradient steady Ricci soliton(Mn,g,f)with nonnegative curvature operator must be rotationally symmetric if it admits a unique equilibrium point and its scalar curvature R(x)satisfies lim_(ρ(x)→∞)R(x)f(x)=C_(0)sup_(x∈M)R(x)with C_(0)>n-2/2.

关键词： Ricci soliton Ricci flow κ-solutions ε-pinched curvature

Classification of gradient steady Ricci solitons with linear curvature decay

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Science China Mathematics 2020年第1期63卷 135-154页

作者： Yuxing deng Xiaohua zhu School of Mathematics and Statistics Beijing Institute of TechnologyBeijing 100081China School of Mathematical Sciences and BICMR Peking UniversityBeijing 100871China

In this paper,we study steady Ricci solitons with a linear decay of sectional *** particular,we give a complete classification of 3-dimensional steady Ricci solitons and 4-dimensional K-noncollapsed steady Ricci solit... 详细信息

关键词： Ricci flow steady Ricci solitons rotational symmetry

Effect of High Positive Acceleration(+Gz) Environment on Dental Implant Osseointegration:A Preliminary Animal Study

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Biomedical and Environmental Sciences 2019年第9期32卷 687-698页

作者： zhu Xiao Ru deng Tian Zheng PANG jian Liang LIU Bing KE Jie Department of Stomatology Air Force Medical Center PLA

Objective To observe the effect of high positive acceleration(+Gz) environment on dental implant osseointegration in a rabbit model and to investigate its *** Forty-eight New Zealand white rabbits were randomly divided into 6 groups. The rabbit’s mandibular incisors were extracted and 1 implant was placed in each socket immediately. After 1 week of rest, the rabbits were exposed to a high +Gz environment, 3 times a week. The rabbits were sacrificed at 3 weeks(2 weeks +Gz exposure), 5 weeks(4 weeks +Gz exposure), and 12 weeks(4 weeks +Gz exposure and 7 weeks normal environment) after surgery, respectively. Specimens were harvested for micro-CT scanning, histological analysis, and real-time polymerase chain reaction *** Compared with those in the control group, the mRNA expression levels of bone morphogenetic protein-2(BMP-2), osteopontin(OPN), and transforming growth factor-β1(TGF-β1)were significantly lower(P < 0.05), while the mRNA expression level of receptor activator of nuclear factor κB ligand(RANKL) and the RANKL/osteoprotegerin(OPG) ratio were significantly higher(P < 0.05)at 3 weeks;values of bone volume fraction, trabecular number, bone-implant contact(BIC), and TGF-β1 and OPG mRNA expression levels were significantly lower(P < 0.05), and the value of trabecular separation, RANKL mRNA expression level and RANKL/OPG ratio were significantly higher(P < 0.05) at 5 weeks;and the value of BIC was still significantly lower(P < 0.05) at 12 weeks in the experimental *** Early exposure to the high +Gz environment after implant surgery might have an adverse effect on osseointegration, and its mechanism could be related to the inhibition of osteoblast activity and promotion of osteoclast activity.

关键词： Positive acceleration Osseointegration Dental implant Micro-CT Real-time polymerase chain reaction Osteoblast

Enhanced Kerr Nonlinearities Caused by Cross Talk Between Optical and Microwave Transitions

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Communications in Theoretical Physics 2008年第10期50卷 961-964页

作者： HU Zheng-Feng deng jian-Liao DU Chun-Guang WANG Yu-zhu The Key Laboratory of Quantum Optics Shanghai Institute of Optics and Fine Mechanics Chinese Academy of Science Shanghai 201800 China Department of Physics Tsinghua University Beijing 100084 China

We investigate the enhanced Kerr nonlinearities in four-level atomic vapors driven by a coupling,probe andmicrowave *** the optical one-photon and two-photon resonant conditions,the linear and nonlinear responsesof the weak probe field can be modified by the cross talk among optical and microwave *** enhanced Kerrnonlinearity can form bright optical solitons of the probe field.

关键词： cross-phase modulation Kerr nonlinearity atom-field interaction

Effects of frost action on soil physical properties of plough pan

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Chinese Science Bulletin 1999年第5期44卷 445-448页

作者： Ximin deng jian Wang Wenshan zhu Duansheng Chen Liping Liu Chinese Agr Univ Dept Hort Beijing 100094 Peoples R China Chinese Agr Univ Dept Soil & Water Sci Beijing 100094 Peoples R China Chinese Agr Univ Dept Agron Beijing 100094 Peoples R China Chinese Agr Univ Dept Construct Beijing 100094 Peoples R China

Undisturb ed soil cores of loamy clay plough pan were subjected to the treatments of freezing and thawing in laboratory. The effects of frost action on its bulk density, porosity, and hydraulic conductivity were investigated. The results indicate that freezing and thawing significantly reduced the bulk density of plough pan and increased its porosity and hydraulic conductivity. The reduction in the bulk density was closely related to the average daily soil minimum temperature and soil water content.

关键词： plough pan soil physical properties frost action.

Analysis of hot leg natural circulation under station blackout severe accident

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Nuclear Science and Techniques 2007年第2期18卷 123-128页

作者： deng jian CAO Xuewu School of Nuclear Science and Engineering Shanghai Jiaotong University Shanghai 200240 China

Under severe accidents, natural circulation flows are important to influence the accident progression and result in a pressurized water reactor (PWR). In a station blackout accident with no recovery of steam generator (SG) auxiliary feedwater (TMLB' severe accident scenario), the hot leg countercurrent natural circulation flow is analyzed by using a severe-accident code, to better understand its potential impacts on the creep-rupture timing among the surge line, the hot leg, and SG tubes. The results show that the natural circulation may delay the failure time of the hot leg. The recirculation ratio and the hot mixing factor are also calculated and discussed.

关键词：压水堆全场断电严重事故热管段自然循环

Photo-induced transformations of Hg(Ⅱ) species in the presence of Nitzschia hantzschiana,ferric ion,and humic acid

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Journal of Environmental Sciences 2010年第1期22卷 76-83页

作者： Lin deng Nansheng deng Liwei Mou Fangtong zhu Department of Municipal Engineering Southeast University Nanjing 210096 China School of Resources and Environmental Science Wuhan University Wuhan 430072 China

Effects of algae Nitzschia hantzschiana, Fe（Ⅲ） ions, humic acid, and pH on the photochemical reduction of Hg（Ⅱ） using the irradiation of metal halide lamps （λ〉 365 nm, 250 W） were investigated. The photoreduction rate of Hg（Ⅱ） was found to increase with increasing concentrations of algae, Fe（Ⅲ） ions, and humic acid. Alteration of pH value affected the photoreduction of Hg（Ⅱ） in aqueous solution with or without algae. The photoreduction rate of Hg（Ⅱ） decreased with increasing initial Hg（Ⅱ） concentration in aqueous solution in the presence of algae. The photochemical kinetics of initial Hg（Ⅱ） and algae concentrations on the photoreduction of Hg（Ⅱ） were studied at pH 7.0. The study on the total Hg mass balance in terms of photochemical process revealed that more than 42% of Hg（Ⅱ） from the algal suspension was reduced to volatile metallic Hg under the conditions investigated.

关键词： photoreduction Nitzschia hantzschiana Hg(Ⅱ) Fe(Ⅲ) humic acid