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Unlocking fast Li-ion transport in micrometer-sized Mn-based cation-disordered rocksalt cathodes

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Journal of Energy Chemistry 2024年第12期99卷 645-653页

作者： Yuchen Zhang Hao Chen Runze Yu Wei Yang jia he Haoyang Li Xianhu Sun Zhengyan lun School of Chemical Sciences University of Chinese Academy of SciencesBeijing 100049China Binzhou Institute of Technology Weiqiao-UCAS Science and Technology ParkBinzhou 256606ShandongChina Department of Materials Science and Engineering Tsinghua Shenzhen International Graduate SchoolShenzhen 518055GuangdongChina

The development of cation-disordered rocksalt(DRX)cathodes has garnered worldwide attention due to their high capacity,broad chemical space and excellent structural ***,their low intrinsic Li-ion conductivity necessitates extensive particle pulverization,typically achieved through ball-milling process,which impedes large-scale *** this work,we present a proton-exchange assisted strategy to activate the Li-ion transport in Mn-based DRX ***-range spinel-like ordering is observed to form within the DRX matrix after the post treatment,which significantly enhances the intrinsic Li ion ***,more than 280 mAh g^(-1)discharge capacity can be delivered at a slow rate from micrometer-sized particles with an overall disordered cation arrangement,which retains more than150 m Ah g^(-1)when cycled at a very high rate of 2000 mA g^(-1).Furthermore,we also demonstrate that the electrochemical performance of the post-treated cathodes can be further optimized by fine-tuning the reaction parameters.

关键词： Cation-disordered rocksalt cathodes Partially-disordered spinel Proton-exchange Short-range order

Entropy engineering in CaZn_(2)Sb_(2)-YbMg_(2)Sb_(2)Zintl alloys for enhanced thermoelectric performance

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Rare Metals 2022年第9期41卷 2998-3004页

作者： Ke-jia Liu Zong-Wei Zhang Chen Chen Li-Hua Wei Huo-lun he Jun Mao Qian Zhang School of Materials Science and Engineering and Institute of Materials Genome&Big DataHarbin Institute of TechnologyShenzhen518055China Department of Mechanical Engineering The University of Hong KongHong Kong999077China State Key Laboratory of Advanced Welding and Joining Harbin Institute of TechnologyHarbin150001China

The significant atomic disorder induced by entropy engineering can effectively suppress lattice thermal conductivity and improve thermoelectric *** variety of compositions of Zintl phases offers a wide range of possibilities for entropy *** we successfully prepared a five-component solid solution(CaZn_(2)Sb_(2))_(0.5)(YbMg_(2)Sb_(2))_(0.5) with a configurational entropy of~1.40R,whereR is the gas *** a result,the room-temperature lattice thermal conductivity was only~0.68 W·m^(-1)·K^(-1),which is lower than that of all AM_(2)Sb_(2) Zintl phases.

关键词： alloys entropy performance

Optimal redundancy allocation for reliability systems with imperfect switching

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Journal of Systems Engineering and Electronics 2014年第2期25卷 332-339页

作者： lun Ran Jinlin Li Xujie jia Hongrui Chu School of Management and Economics Beijing Institute of Technology College of Science Minzu University of China

The problem of stochastically allocating redundant com- ponents to increase the system lifetime is an important topic of reliability. An optimal redundancy allocation is proposed, which maximizes the expected lifetime of a reliability system with sub- systems consisting of components in parallel. The constraints are minimizing the total resources and the sizes of subsystems. In this system, each switching is independent with each other and works with probability p. Two optimization problems are studied by an incremental algorithm and dynamic programming technique respectively. The incremental algorithm proposed could obtain an approximate optimal solution, and the dynamic programming method could generate the optimal solution,

关键词： optimal redundancy allocation parallel imperfectswitching incremental algorithm dynamic programming.

Vacuum Susceptibility Calculation

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Communications in Theoretical Physics 2005年第3X期44卷 514-518页

作者： SHI Yuan-Mei PING jia-lun Department of Physics Nanjing Normal University Nanjing 210097 China School of Physics and Microelectronics Shandong University Jinan 250100 China

The vector susceptibility is investigated numerically in the Dyson-Schwinger approach. The results agree with those obtained analytically previously by using a simple gluon propagator.

关键词： Dyson-Schwinger equation vacuum susceptibility full gluon propagator

Prediction model of in-hospital mortality in elderly patients with acute heart failure based on retrospective study

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Journal of Geriatric Cardiology 2017年第11期14卷 669-678页

作者： Qian jia Yu-Rong WANG Ping he Xue-Liang HUANG Wei YAN Yang MU Ktm-lun he Ya-Ping TIAN Core Laboratory of Translational Medicine Chinese PLA General Hospital Beijing China Department of Cardiology School of Medicine Nankai University Tianjin China Department of Statistics Peking University Health Science Center Beijing China Department of Clinical Biochemistry Chinese PLA General Hospital Beijing China Department of Cardiology Chinese PLA General Hospital Beijing China

Objectives The aim of this study was to develop a clinical risk model that is predictive of in-hospital mortality in elderly patients hos- pitalized with acute heart failure （AHF）. Methods 2486 patients who were 60 years and older from intensive care units of Cardiology De- partment in the hospital were analyzed. Independent risk factors for in-hospital mortality were obtained by binary logistic regression and then used to establish the risk prediction score system （RPSS）. The area under the curve （AUC） of receiver operator characteristic and C-statistic test were adopted to assess the performance of RPSS and to compare with previous get with the guidelines-heart failure （GWTG-HF）. Re- sults By binary logistic regression analysis, heart rate （OR： 1.043, 95% CI： 1.030-1.057, P 〈 0.001）, left ventricular ejection fraction （OR： 0.918, 95% CI： 0.833~）.966, P 〈 0.001）, pH value （OR： 0.001, 95% CI： 0.000-0.002, P 〈 0.001）, renal dysfunction （OR： 0.120, 95% CI： 0.066M）.220, P 〈 0.001） and NT-pro BNP （OR： 3.463, 95% CI： 1.870-6.413, P 〈 0.001） were independent risk factors of in-hospital mortal- ity for elderly AHF patients. Additionally, RPSS, which was composed of all the above-mentioned parameters, provided a better risk predic- tion than GWTG-THF （AUC： 0.873 vs. 0.818, P = 0.016）. Conclusions Our risk prediction model, RPSS, provided a good prediction for in-hospital mortality in elderly patients with A/IF.

关键词： Acute heart failure N-hospital mortality Prediction model Risk factors

Relationship between hydrogenation degree and pyrolysis performance of jet fuel

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Chinese Journal of Chemical Engineering 2024年第4期68卷 35-42页

作者： Qing Liu Tinghao jia lun Pan Jijun Zou Xiangwen Zhang Key Laboratory for Green Chemical and Technology School of Chemical Engineering and TechnologyTianjin UniversityTianjin 300072China Haihe Laboratory of Sustainable Chemical Transformations Tianjin 300192China Zhejiang Institute of Tianjin University Ningbo 315201China Zhejiang Provincial Key Laboratory of Advanced Chemical Engineering Manufacture Technology College of Chemical and Biological EngineeringZhejiang UniversityHangzhou 310027China

Understanding the relationship between the chemical composition and pyrolysis performance of endothermic hydrocarbon fuel(EHF) is of great significance for the design and optimization of advanced EHFs. In this work, the effect of deep hydrogenation on the pyrolysis of commercial RP-3 is *** with different hydrogenation degrees were obtained by the partially and completely catalytic hydrogenation and their pyrolysis performances were investigated using an apparatus equipped with an electrically heated tubular reactor. The results show that with the increase of hydrogenation degree, fuel conversion almost remains constant during the pyrolysis process(500-650°C, 4 MPa);however, the heat sink increases slightly, and the anti-coking performance significantly improves, which are highly related to their H/C ratios. Detailed characterisations reveal that the difference of the pyrolysis performance can be ascribed to the content of aromatics and cycloalkanes: the former are prone to initiate secondary reactions to form coking precursors, while the latter could act as the hydrogen donor and release hydrogen, which will terminate the radical propagation reactions and suppress the coke deposition. This work should provide the guidance for upgrading EHFs by modulating the composition of EHFs.

关键词： RP-3 Fuel Pyrolysis Hydrogenation Deposition

Discoveries and functions of virus-encoded MicroRNAs

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Chinese Science Bulletin 2008年第2期53卷 169-177页

作者： jia WanZhong LI Zhi lun ZhaoRong Center for Parasitic Organisms State Key Laboratory of Biocontrol School of Life Sciences and Key Laboratory of Tropical Diseases Control of the Ministry of Education Zhongshan Medical College Sun Yat-Sen (Zhongshan) University Guangzhou 510275 China Key Laboratory of Veterinary Parasitology of Gansu Province State Key Laboratory of Veterinary Etiological Biology Lanzhou Veterinary Research Institute Chinese Academy of Agricultural Sciences Lanzhou 730046 China

Virus-encoded microRNAs (miRNAs) are a new kind of miRNAs that regulate the expression of target gene in host cells or viruses through inducing cleavage of mRNA, repressing translation, etc., and change the processes of host cells or replicate viruses to escape or resist immune surveillance of host and protect viruses themselves. It has become a hot topic to discover viral genes encoding miRNAs and their target genes, and to identify their functions. This review provides background information on the history of virally encoded miRNAs including their genomic distribution, functions and mechanisms. In addition, we discuss the similarities and differences between virus- and host-encoded miRNAs, the future directions of researches in viral miRNAs and their applications in diseases control and therapy.

关键词： RNA 病毒编码基因调节函数

Interface enhanced well-dispersed Co9S8 nanocrystals as an efficient polysulfide host in lithium–sulfur batteries

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Journal of Energy Chemistry 2020年第9期29卷 109-115,I0004页

作者： Xue Liu Qiu he Hong Yuan Chong Yan Yan Zhao Xu Xu jia-Qi Huang Yu-lun Chueh Qiang Zhang Liqiang Mai State Key Laboratory of Advanced Technology for Materials Synthesis and Processing Wuhan University of TechnologyWuhan 430070HubeiChina State Key Laboratory of Silicate Materials for Architectures Wuhan University of TechnologyWuhan 430070HubeiChina Beijing Key Laboratory of Green Chemical Reaction Engineering and Technology Department of Chemical EngineeringTsinghua UniversityBeijing 100084China Advanced Research Institute of Multidisciplinary Science Beijing Institute of TechnologyBeijing 100081China Department of Materials Science and Engineering Taiwan Tsinghua UniversityHsinchu 30013TaiwanChina

The high specific capacity and energy density of lithium-sulfur batteries have attracted strong considerations on their fundamental mechanism and energy ***,polysulfide shuttle is still the key issue that impedes the development of Li-S *** nanocrystal hosts for polysulfide immobilization and conversion is a promising *** this contribution,we have investigated well-dispersed Co9S8 nanocrystals grown on graphene oxide(GO)nanosheets with different degrees of dispersion as cathode host materials for Li-S *** Co9S8-GO composite with 1 wt%GO(GCS1)has an average crystal size of 76 nm and shows the strongest adsorption capability toward lithium *** used as the host material for the cathode of Li-S batteries,the GCS1-sulfur composite exhibits an initial specific capacity of^-1000 mAh g^-1 at 0.5 C and shows an average decay rate of 0.11%for 500 *** work on the dispersion control of Co9S8 nanocrystals may inspire more investigations on well-dispersed nanocrystal based hosts for Li-S batteries.

关键词： Metal sulfides Composite sulfur cathode Cobalt sulfides Lithium-sulfur batteries Electrocatalysis

Residual dynamics of thiacloprid in medical herbs marjoram,thyme,and camomile in soil

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Journal of Environmental Sciences 2007年第2期19卷 205-209页

作者： YU Yun-long WU jia-lun STAHLER Matthias PESTEMER Wilfried Department of Plant Protection College of Agriculture and Biotechnology Zhejiang University Hangzhou 310029 China Institute for Ecotoxicology and Ecochemistry in Plant Protection Federal Biological Research Centre for Agriculture and Forestry Koenigin-Luise-Strafle 19 D-14195 Berlin Germany

Thiacloprid is a new insecticide of the chloronicotinyl family. To assess its risk after application, residual characteristics of thiacloprid in marjoram, thyme, and camomile and in soil were studied under field conditions. The active ingredient was extracted from the plant material using a mixture of acetone-water. After filtration, the extract was concentrated to the aqueous phase, diluted with water, and portioned against ethyl acetate on a matrix solid phase dispersion column. Thiacloprid was extracted from soil using a mixture of methanol-water, filtered, and *** （clean up） with dichloromethane. The residues were quantified using HPLC-MS-MS. The methods were validated by recovery experiments. Thiacloprid residues in marjoram, thyme, and camomile and in soil persisted beyond 10, 14, 14, and 21 d but no residues were detected after 14, 21, 21, and 28 d, respectively. The data obtained in this study indicated that the biexponential model is more suitable than the first-order function to describe the decline of thiacloprid in fresh marjoram, fresh thyme, and dried camomile flowers with half-life （t1/2） of 1.1, 0.7, and 1.2 d, respectively. However, both the first-order function and biexponential model were found to be applicable for dissipation of thiacloprid in soil with almost the same t1/2 values of 3.5 and 3.6 d. The results indicated that thiacloprid dissipates rapidly and does not accumulate in the tested herbs and in soil.

关键词： thiacloprid marjoram (Majorana hortensis) thyme (Thymus vilgaris) camomile (Matricaria chamomilla) residue