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Occupancy of rooms in urban residential buildings by users in cold areas of China

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Building Simulation 2023年第3期16卷 483-497页

作者： qi Dong Zikai Ma cheng Sun School of Architecture Harbin Institute of TechnologyHarbin 150006China Key Laboratory of Cold Region Urban and Rural Human Settlement Environment Science and Technology Ministry of Industry and Information TechnologyHarbin 150006China

Occupancy is used to represent the movements and locations of users among various zones of buildings,and it is the basis of all other daily energy consumption behaviors.This study investigated eight families in cold areas of China based on occupancy measurements obtained in four main rooms,i.e.,living room,bedroom,kitchen,and bathroom.In particular,we analyzed the duration of user occupancy and hourly mean occupancy,and characterized their regular and random features.According to the results,we developed an event-based occupancy model using an inhomogeneous Markov chain,where the rooms were modeled and daily events were divided into three categories according to their randomness.We established a new method for conversion between event characteristic parameters and a transition probability matrix,as well as an overlap avoidance method for active events.The model was then validated using real data.The results showed that the model performed well in terms of two evaluation criteria.The model should improve the accuracy of simulations of occupancy.

关键词： event occupancy urban residential building simulation cold areas of China

Evaluation of the performance of GNSS-based velocity estimation algorithms

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Satellite Navigation 2022年第3期3卷 162-177,I0004页

作者： Li Ji Rui Sun Qi Cheng Junhui Wang College of Civil Aviation Nanjing University of Aeronautics and AstronauticsNanjing211106China

Global Navigation Satellite System(GNSS)based velocity estimation is one of the most cost-effective and widely used methods in determining velocity in geodesy and transport applications.Highly accurate and reliable velocity measurements can be obtained by exploiting the raw Doppler,carrier phase,and pseudorange measurements with a GNSS receiver.There are several approaches to GNSS-based velocity determination.This paper investigates the characteristics of the approaches which are currently popular and applicable to the observations of Global Positioning System(GPS),BeiDou Navigation Satellite System(BDS),and their combination(GPS/BDS).Specifically,it evaluates the performance of the velocity estimated based on the Raw Doppler method,the Time-Differenced Pseudorange method,the Time-Differenced Carrier Phase method,and the Double-Differenced Carrier Phase method,in both static and dynamic modes and in open and urban scenarios.The experiments show that BDS has the advantages in delivering accurate velocity determinations over GPS in the Asia–Pacific region,and the effectiveness of the GPS/BDS in improving the overall accuracy of velocity determination in complex urban scenarios.

关键词： GNSS BDS GPS Vehicle velocity determination

A faster method to compute primitive elements and discrete logarithms of factor base in Artin-Schreier extensions

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Science China(Information Sciences) 2019年第9期62卷 214-216页

作者： Dianyan XIAO Qi Cheng Institute for Advanced Study Tsinghua University School of Computer Science University of Oklahoma

Dear editor,The discrete logarithm problem is a classical problem in mathematics and widely used in cryptography [1–4]. The pre-computation of discrete logarithms of factor base is a crucial and extremely expensive s... 详细信息

关键词： A faster method to compute primitive elements and discrete logarithms of factor base in Artin-Schreier extensions

Representations of Bihom-Lie Algebras

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Algebra Colloquium 2022年第1期29卷 125-142页

作者： Yongsheng cheng Huange qi School of Mathematics and Statistics Henan University KaifengHenan 475004China

A Bihom-Lie algebra is a generalized Hom-Lie algebra endowed with two commuting multiplicative linear maps.In this paper,we study representations of Bihom-Lie algebras.In particular,derivations,central extensions,derivation extensions,the trivial representation and the adjoint representation of Bihom-Lie algebras are studied in detail.

关键词： Bihom-Lie algebras derivations cohomology representations of Bihom-Lie algebras

Thermo-sensitive Porous Polymer Membrane-immobilized Cellulose as a Switchable Enzyme Reactor for Tuning Its Enzymolysis via Variation Temperature

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Chemical Research in Chinese Universities 2023年第6期39卷 992-997页

作者： qiAO Juan ZHANG Xinya cheng cheng qi Li Beijing National Laboratory for Molecular Sciences Key Laboratory of Analytical Chemistry for Living BiosystemsInstitute of ChemistryChinese Academy of SciencesBeijing 100190P.R.China School of Chemical Sciences University of Chinese Academy of SciencesBeijing 100049P.R.China School of Pharmacy Xinxiang Medical UniversityXinxiang 453003P.R.China College of Chemistry&Environmental Science Hebei UniversityBaoding 071002P.R.China

Immobilization of enzymes onto porous membranes has attracted considerable attention in recent years.However,enhancing the enzymolysis efficiency of the resulting enzyme reactors by varying the environmental conditions poses a great challenge.In this work,poly(styrene-maleic anhydride-N,N-dimethylacrylamide)was prepared and utilized to construct a thermo-sensitive porous polymer membrane-based enzyme reactor(TS-PPMER)after cellulase was immobilized onto the support by covalent bonding.The catalytic activity of the nano-reactor was evaluated by measuring the yield of the product,glucose,at different temperatures with carboxymethylcellulose as the substrate.Interestingly,the polymer chains coiled and formed numerous nano-pores at a high temperature,which induced the confine effect and greatly boosted the enzymolysis efficiency of TS-PPMER.Furthermore,the proposed TS-PPMER was applied in the hydrolysis of green plant leaves in Epipremnum aureum.This work shows great potential in obtaining biological resources by an environmentally friendly approach using smart polymer-based nano-reactors.

关键词： Thermo-sensitive porous polymer membrane Cellulase reactor Catalytic efficiency Glucose Plant leaf

Top Five Stories of the Cellular Landscape and Therapies of Atherosclerosis:Current Knowledge and Future Perspectives

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Current Medical Science 2024年第1期44卷 1-27页

作者： qi PAN cheng CHEN Yue-jin YANG State Key Laboratory of Cardiovascular Disease Department of CardiologyFuwai HospitalNational Center for Cardiovascular DiseasesChinese Academy of Medical Science and Peking Union Medical CollegeBeijing 100037China

Atherosclerosis(AS)is characterized by impairment and apoptosis of endothelial cells,continuous systemic and focal inflammation and dysfunction of vascular smooth muscle cells,which is documented as the traditional cellular paradigm.However,the mechanisms appear much more complicated than we thought since a bulk of studies on efferocytosis,transdifferentiation and novel cell death forms such as ferroptosis,pyroptosis,and extracellular trap were reported.Discovery of novel pathological cellular landscapes provides a large number of therapeutic targets.On the other side,the unsatisfactory therapeutic effects of current treatment with lipid-lowering drugs as the cornerstone also restricts the efforts to reduce global AS burden.Stem cell-or nanoparticle-based strategies spurred a lot of attention due to the attractive therapeutic effects and minimized adverse effects.Given the complexity of pathological changes of AS,attempts to develop an almighty medicine based on single mechanisms could be theoretically challenging.In this review,the top stories in the cellular landscapes during the initiation and progression of AS and the therapies were summarized in an integrated perspective to facilitate efforts to develop a multi-targets strategy and fill the gap between mechanism research and clinical translation.The future challenges and improvements were also discussed.

关键词： atherosclerosis transdifferentiation extracellular traps efferocytosis stem cell nanoparticles

Electrochemical Synthesis of Sulfonyl Fluorides with Triethylamine Hydrofluoride

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Chinese Journal of Chemistry 2022年第14期40卷 1687-1692页

作者： Lei Zhang Xu cheng qi-Lin Zhou State Key Laboratory and Institute of Elemento-Organic Chemistry College of ChemistryNankai UniversityTianjin 300071China Institute of Chemistry and Biomedical Sciences Jjiangsu Key Laboratory of Advanced Organic MaterialsNational Demon-stration Center for Experimental Chemistry EducationSchool of Chemistry and Chemical EngineeringNanjing UniversityNanjingJjiangsu 210023China

Hydrofluoride is an industry-preferred fluoride source,and finds extensively application to manufacture diverse fluoro chemicals.The Et3N-3HF complex is a liquid HF with improve safety.In this work,we report electrochemical synthesis of a series of sulfonyl fluoride with Et3N-3HF as fluoride source.The sulfinic salt is a smell-less,non-volatile,and air-stable sulfur source in this reaction.With the combination of Et3N-3HF and aryl/alkyl sulfinic salt,the sulfonyl fluorides are achieved without the use of external oxidant.In addition,we demonstrate further advantage in a tandem reaction involving Pd-catalyzed C—S cross-coupling and formation of S—F bond.A variety of functional groups including amino acids,heterocycles,halides are well tolerated.

关键词： Electrochemicstry Fluorides Click chemistry Sulfinic salt Dehydrogenation

A systematic COSMO-RS study on mutual solubility of ionic liquids and C6-hydrocarbons

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Green Chemical Engineering 2024年第1期5卷 97-107页

作者： Chuxin qi Zhen Song Hongye cheng Lifang Chen Zhiwen qi State Key Laboratory of Chemical Engineering School of Chemical EngineeringEast China University of Science and Technology130 Meilong RoadShanghai200237China

When considering the usage of ionic liquids(ILs)for reactions and separations involving non-polar or weak-polar hydrocarbons,the knowledge of the mutual solubility behaviors of ILs and hydrocarbons is of the utmost importance.In this work,taking four typical C6-hydrocarbons namely benzene,cyclohexene,cyclohexane,and hexane as representatives,the mutual solubility of ILs and non-polar or weak-polar hydrocarbons are systematically studied based on the COSMO-RS model.The reliability of COSMO-RS for these systems is first evaluated by comparing experimental and predicted hydrocarbon-in-IL activity coefficient at infinite dilution and binary/ternary liquid-liquid equilibria of related systems.Then,the mutual solubility of the four hydrocarbons and13,650 ILs(composed by 210 cations and 65 anions)are predicted.The effect of different IL structural characteristics including alkyl chain length,cation family/symmetry/functional group,and anion on the IL-hydrocarbon mutual solubility behaviors are further analyzed by the analyses of interaction energy and screen charge distribution.The mutual solubility databases and the structural effects identified thereon could provide useful guidance for IL selection in related applications.

关键词： C6-hydrocarbons Ionic liquids Mutual solubility COSMO-RS Structural effect analysis

Perspectives in Biological Nitrogen Fixation Research

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Journal of Integrative Plant Biology 2008年第7期50卷 786-798页

作者： Qi Cheng Department of Biochemistry Redox Biology Center University of Nebraska-Lincoln Lincoln Nebraska 68588 USA

Nitrogen fixation, along with photosynthesis is the basis of all life on earth. Current understanding suggests that no plant fixes its own nitrogen. Some plants （mainly legumes） fix nitrogen via symbiotic anaerobic microorganisms （mainly rhizobia）. The nature of biological nitrogen fixation is that the dinitrogenase catalyzes the reaction-splitting triple-bond inert atmospheric nitrogen （N2） into organic ammonia molecule （NH3）. All known nitrogenases are found to be prokaryotic, multi-complex and normally oxygen liable. Not surprisingly, the engineering of autonomous nitrogen-fixing plants would be a long-term effort because it requires the assembly of a complex enzyme and provision of anaerobic conditions. However, in the light of evolving protein catalysts, the anaerobic enzyme has almost certainly been replaced in many reactions by the more efficient and irreversible aerobic version that uses O2. On the other hand, nature has shown numerous examples of evolutionary convergence where an enzyme catalyzing a highly specific, O2-requiring reaction has an oxygen-independent counterpart, able to carry out the same reaction under anoxic conditions. In this review, I attempt to take the reader on a simplified journey from conventional nitrogenase complex to a possible simplified version of a yet to be discovered light-utilizing nitrogenase.

关键词： aerobic anaerobic anoxic convergent enzyme light-independent light-utilizing nitrogen fixation nitrogenase oxic protochlorophyllide reductase.