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Chinese Journal of Chemistry 2023年第3期41卷 294-300页

作者： jian Chen Gao deng You Wang Shaolin zhu State Key Laboratory of Coordination Chemistry Jiangsu Key Laboratory of Advanced Organic MaterialsSchool of Chemistry and Chemical EngineeringNanjing UniversityNanjingJiangsu210093 China School of Chemistry and Chemical Engineering Henan Normal UniversityXinxiangHenan453007 China

NiH-catalyzed multicomponent reductive hydrofunctionalization of alkenes is an attractive but poorly explored approach to rapidly increasing molecular complexity.In this process,the selective generation of the desired product can be challenging.Herein,we report that a highly chemo-,regio-and enantioselective reductive hydrocarbonylation of alkenes has been achieved using a chloroformate ester as a source of CO.A wide range of structurally diverseα-hydroxy ketones,privileged structural elements in bioactive molecules and useful building blocks,were obtained from such reactions with high enantiomeric purity.

关键词： Alkenes Asymmetric catalysis Hydrofunctionalization Multicomponent reactions Nickel Nickel hydride Synthetic methods Hydrocarbonylation

Model predictive control of indoor thermal environment conditioned by a direct expansion air conditioning system

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Building Simulation 2023年第3期16卷 357-378页

作者： Yudong Xia Ming zhu Aipeng jiang jian Wang Xiaoxia Bai Shiming deng School of Automation(School of Artificial Intelligence) Hangzhou Dianzi UniversityHangzhouChina Department of Building Environment and Energy Engineering The Hong Kong Polytechnic UniversityHong KongChina Department of Mechanical and Industrial Engineering Qatar UniversityDohaQatar

Temperature and humidity are two important factors that influence both indoor thermal comfort and air quality.Through varying compressor and supply fan speeds of a direct expansion(DX)air conditioning(A/C)unit,the air temperature and humidity in the conditioned space can be regulated simultaneously.However,most existing controllers are designed to minimize the tracking errors between the system outputs with their corresponding settings as quickly as possible.The energy consumption,which is directly influenced by the compressor and supply fan speeds,is not considered in the relevant controller formulations,and thus the system may not operate with the highest possible energy efficiency.To effectively control temperature and humidity while minimizing the system energy consumption,a model predictive control(MPC)strategy was developed for a DX A/C system,and the development results are presented in this paper.A physically-based dynamic model for the DX A/C system with both sensible and latent heat transfers being considered was established and validated by experiments.To facilitate the design of MPC,the physical model was further linearized.The MPC scheme was then developed by formulating the objective function which sought to minimize the tracking errors of temperature and moisture content while saving energy consumption.Based on the results of command following and disturbance rejection tests,the proposed MPC scheme was capable of controlling temperature and humidity with adequate control accuracy and sensitivity.In comparison to linear-quadratic-Gaussian(LQG)controller,better control accuracy and lower energy consumption could be realized when using the proposed MPC strategy to simultaneously control temperature and humidity.

关键词： direct expansion air conditioning humidity control model predictive control variable speed operational efficiency

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 desirable.Here,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 time.The 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

A desulphurization strategy for Sonogashira couplings by visible light/copper catalysis

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Organic Chemistry Frontiers 2022年第2期9卷 386-393页

作者： Xuan Li Min jiang Xiaolong zhu Xiuyan Song Qirong deng 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 copper-based catalysts in photoredox transformations has become a rapidly growing area of research and has been actively explored in the past several years.Herein,we have developed a new copper-based catalyst,[(binap)(tpy)Cu]Cl,and applied it in the visible-light promoted Sonogashira coupling reactions.This mild protocol results in various substituted alkynes from simple sulfonium salts which can be easily prepared from commercially available and inexpensive thiols,alcohols,and alkyl halides.This study will broaden the still limited strategies of copper photocatalysts in organic transformations.

关键词： copper visible coupling

Arabidopsis noncoding RNA modulates seedling greening during deetiolation

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Science China(Life Sciences) 2018年第2期61卷 199-203页

作者： Yuqiu Wang jian Li Xing-Wang deng Danmeng zhu State Key Laboratory of Protein and Plant Gene Research Peking-Tsinghua Center for Life Sciences School of Advanced Agricultural Sciences and School of Life Sciences Peking University

Seedling greening is essential for the survival of plants emerging from the soil. The abundance of chlorophyll precursors, including protochlorophyllide(Pchlide), is precisely controlled during the dark-to-light transition, as over-accumulation of Pchlide can lead to cellular photooxidative damage. Previous studies have identified and characterized multiple regulators controlling this important process. HID1(hidden treasure 1) is the first noncoding RNA(ncRNA) found in photomorphogenesis. Under continuous red light,HID1 has been shown to inhibit hypocotyl elongation by repressing the transcription of PIF3(phytochrome interacting factor 3).Here, we report that HID1 acts as a negative regulator of cotyledon greening. Knockdown of HID1 resulted in an increased greening rate of etiolated seedlings relative to wild type when exposed to white light. Genetically, HID1 acts downstream of PIF3 during the dark-to-light transition. The expression of HID1 is not regulated by PIF3 in the dark. Molecularly, the Pchlide content was reduced in dark-grown hid1 mutants than WT. Meanwhile, transcript levels of the protochlorophyllide oxidoreductases known to catalyze Pchlide to chlorophyllide conversion were significantly increased in hid1 seedlings. Thus, our study reveals an additional role of HID1 in the dark-to-light transition in Arabidopsis. Moreover, these results suggest HID1 could regulate distinct targets in different light-mediated developmental processes, and thus is essential to the control of these mechanisms.

关键词： Arabidopsis RNA 幼苗调制过程调整管理者叶绿素控制

Diverse viromes in polar regions: A retrospective study of metagenomic data from Antarctic animal feces and Arctic frozen soil in 2012–2014

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Virologica Sinica 2022年第6期37卷 883-893页

作者： Jun Wang jian Xiao Zheng zhu Siyuan Wang Lei Zhang Zhaojun Fan Yali deng Zhihong Hu Fang Peng Shu Shen Fei deng State Key Laboratory of Virology and National Virus Resource Center Wuhan Institute of VirologyChinese Academy of SciencesWuhan 430071China Xinjiang Key Laboratory of Biological Resources and Genetic Engineering College of Life Science and TechnologyXinjiang UniversityUrumqi830046China China Center for Type Culture Collection(CCTCC) College of Life SciencesWuhan UniversityWuhan430072China Natisonal Emerging Infectious Diseases Laboratories Boston UniversityBostonMA 02118United States Department of Biochemistry Boston University School of MedicineBostonMA 02118United States

Antarctica and the Arctic are the coldest places, containing a high diversity of microorganisms, including viruses,which are important components of polar ecosystems. However, owing to the difficulties in obtaining access to animal and environmental samples, the current knowledge of viromes in polar regions is still limited. To better understand polar viromes, this study performed a retrospective analysis using metagenomic sequencing data of animal feces from Antarctica and frozen soil from the Arctic collected during 2012–2014. The results reveal diverse communities of DNA and RNA viruses from at least 23 families from Antarctic animal feces and 16families from Arctic soils. Although the viral communities from Antarctica and the Arctic show a large diversity,they have genetic similarities with known viruses from different ecosystems and organisms with similar viral proteins. Phylogenetic analysis of Microviridae, Parvoviridae, and Larvidaviridae was further performed, and complete genomic sequences of two novel circular replication-associated protein(rep)-encoding single-stranded(CRESS) DNA viruses closely related to Circoviridae were identified. These results reveal the high diversity,complexity, and novelty of viral communities from polar regions, and suggested the genetic similarity and functional correlations of viromes between the Antarctica and Arctic. Variations in viral families in Arctic soils,Arctic freshwater, and Antarctic soils are discussed. These findings improve our understanding of polar viromes and suggest the importance of performing follow-up in-depth investigations of animal and environmental samples from Antarctica and the Arctic, which would reveal the substantial role of these viruses in the global viral community.

关键词： Arctic soil Antarctica animal feces Metagenomics Virus diversity

Adaptive smoothing length method based on weighted average of neighboring particle density for SPH fluid simulation

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Virtual Reality & Intelligent Hardware 2021年第2期3卷 129-141页

作者： Rongda ZENG Zihao WU Shengbang deng jian zhu Xiaoyu CHI School of Computer Science Guangdong University of TechnologyGuangzhou 510006China Qingdao Research Institute of Beihang University Qingdao 266000China

Background In the smoothed particle hydrodynamics(SPH)fluid simulation method,the smoothing length affects not only the process of neighbor search but also the calculation accuracy of the pressure solver.Therefore,it plays a crucial role in ensuring the accuracy and stability of SPH.Methods In this study,an adaptive SPH fluid simulation method with a variable smoothing length is designed.In this method,the smoothing length is adaptively adjusted according to the ratio of the particle density to the weighted average of the density of the neighboring particles.Additionally,a neighbor search scheme and kernel function scheme are designed to solve the asymmetry problems caused by the variable smoothing length.Results The simulation efficiency of the proposed algorithm is comparable to that of some classical methods,and the variance of the number of neighboring particles is reduced.Thus,the visual effect is more similar to the corresponding physical reality.Conclusions The precision of the interpolation calculation performed in the SPH algorithm is improved using the adaptive-smoothing length scheme;thus,the stability of the algorithm is enhanced,and a larger timestep is possible.

关键词： Fluid simulation SPH Smoothing length Adaptive Particle density

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 mechanism.Methods 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 examination.Results 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 group.Conclusion 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

NiCe bimetallic nanoparticles embedded in hexagonal mesoporous silica (HMS) for reverse water gas shift reaction

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Chinese Chemical Letters 2022年第5期33卷 2590-2594页

作者： Hui Dai Siqi Xiong Yongqing zhu jian Zheng Lihong Huang Changjian Zhou Jie deng Xinfeng Zhang College of Materials and Chemistry&Chemical Engineering Chengdu University of TechnologyChengdu 610059China Department of Chemical Engineering Sichuan UniversityChengdu 610065China School of Chemistry and Chemical Engineering Yancheng Institute of TechnologyYancheng 224051China College of Pharmacy and Bioengineering Chengdu UniversityChengdu 610106China

Reverse water gas shift(RWGS)reaction is a crucial process in CO_(2)utilization.Herein,Ni-and NiCe-containing hexagonal mesoporous silica(Ni-HMS and NiCe-HMS)catalysts were synthesized using an insitu one-pot method and applied for RWGS reaction.At certain reaction temperatures 500-750℃,Ni-HMS samples displayed a higher selectivity to the preferable CO than that of conventionally impregnated Ni/HMS catalyst.This could be originated from the smaller NiO nanoparticles over Ni-HMS catalyst.NiCe-HMS exhibited higher activity compared to Ni-HMS.The catalysts were characterized by means of TEM,XPS,XRD,H_(2)-TPR,CO_(2)-TPD,EPR and N_(2) adsorption-desortion technology.It was found that introduction of Ce created high concentration of oxygen vacancies,served as the active site for activating CO_(2).Also,this work analyzed the effect of the H_(2)/CO_(2)molar ratio on the best NiCe-HMS.When reaction gas H_(2)/CO_(2)molar ratio was 4 significantly decreased the selectivity to CO at low temperature,but triggered a higher CO_(2)conversion which is close to the equilibrium.

关键词： Greenhouse gases Reverse water gas shift reaction CO selectivity CeO_(2) Hexagonal mesoporous silica

Quantum-dot light-emitting diodes with Fermi-level pinning at the hole-injection/hole-transporting interfaces

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Nano Research 2022年第8期15卷 7453-7459页

作者： Maopeng Xu Desui Chen jian Lin Xiuyuan Lu Yunzhou deng Siyu He Xitong zhu Wangxiao Jin Yizheng Jin Zhejiang Key Laboratory for Excited-State Materials State Key Laboratory of Silicon MaterialsDepartment of ChemistryZhejiang UniversityHangzhou 310027China School of Materials Science and Engineering Suzhou University of Science and TechnologySuzhou 215009China

Quantum-dot light-emitting diodes(QLEDs)are multilayer electroluminescent devices promising for next-generation display and solid-state-lighting technologies.In the state-of-the-art QLEDs,hole-injection layers(HILs)with high work functions are generally used to achieve efficient hole injection.In these devices,Fermi-level pinning,a phenomenon often observed in heterojunctions involving organic semiconductors,can take place in the hole-injection/hole-transporting interfaces.However,an in-depth understanding of the impacts of Fermi-level pinning at the hole-injection/hole-transporting interfaces on the operation and performance of QLEDs is still lacking.Here,we develop a set of NiOx HILs with controlled work functions of 5.2–5.9 eV to investigate QLEDs with Fermi-level pinning at the hole-injection/hole-transporting interfaces.The results show that despite that Fermi-level pinning induces identical apparent hole-injection barriers,the red QLEDs using HILs with higher work functions show improved efficiency roll-off and better operational stability.Remarkably,the devices using the NiOx HILs with a work function of 5.9 eV demonstrate a peak external quantum efficiency of~18.0%and a long T95 operational lifetime of 8,800 h at 1,000 cd·m^(−2),representing the best-performing QLEDs with inorganic HILs.Our work provides a key design principle for future developments of the hole-injection/hole-transporting interfaces of QLEDs.

关键词： quantum-dot light-emitting diodes Fermi-level pinning hole-injection/hole-transporting interfaces work function performance