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Solid-state lithium-ion batteries for grid energy storage:opportunities and challenges

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science china Chemistry 2024年第1期67卷 43-66页

作者： Xin Chang Yu-Ming Zhao Boheng Yuan Min Fan Qinghai Meng Yu-Guo Guo Li-Jun wan CAS Key Laboratory of Molecular Nanostructure and Nanotechnology CAS Research/Education Center for Excellence in Molecular SciencesBeijing National Laboratory for Molecular Sciences(BNLMS)Institute of ChemistryChinese Academy of Sciences(CAS)Beijing 100190China University of chinese academy of sciences Beijing 100049China

The energy crisis and environmental pollution drive more attention to the development and utilization of renewable *** the capricious nature of renewable energy resource,it has difficulty supplying electricity directly to consumers stably and efficiently,which calls for energy storage systems to collect energy and release electricity at peak *** to their flexible power and energy,quick response,and high energy conversion efficiency,lithium-ion batteries stand out among multiple energy storage technologies and are rapidly deployed in the *** superior performance and ensuring the safety of energy storage systems,intrinsically safe solid-state electrolytes are expected as an ideal alternative to liquid *** this review,we systematically evaluate the priorities and issues of traditional lithium-ion batteries in grid energy *** lithium-ion batteries containing liquid electrolytes,solid-state lithium-ion batteries have the potential to play a more significant role in grid energy *** challenges of developing solid-state lithium-ion batteries,such as low ionic conductivity of the electrolyte,unstable electrode/electrolyte interface,and complicated fabrication process,are discussed in ***,the safety of solid-state lithium-ion batteries is *** the obtained insights,inspiring prospects for solid-state lithium-ion batteries in grid energy storage are depicted.

关键词： lithium-ion batteries grid energy storage solid-state electrolytes interface stability

Giant piezotronic effect in ferroelectric field effect transistor

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Nano Research 2024年第9期17卷 8465-8471页

作者： Haiming Zhang Mengshuang Chi Shidai Tian Tian Liang Jitao Liu Xiang Zhang Lingyu wan Zhong Lin wang Junyi Zhai Center on Nanoenergy Research School of Physical Science&TechnologyGuangxi UniversityNanning 530004China beijing Key Laboratory of Micro-Nano Energy and Sensor Center for High-Entropy Energy and SystemsBeijing Institute of Nanoenergy and NanosystemsChinese Academy of SciencesBeijing 101400China School of Nanoscience and Engineering University of Chinese Academy of ScienceBeijing 100049China School of Electronic science and Engineering University of Electronic Science and Technology of ChinaChengdu 610054China Georgia Institute of Technology AtlantaGA 30332USA

The piezotronics effect utilizes a piezopotential to modulate and control current in *** materials,as a type of piezoelectric materials,possess piezoelectric coefficients that are significantly larger than those found in conventional piezoelectric ***,we propose a strain modulated ferroelectric field-effect transistor(St-FeFET)utilizing external strain instead of gate voltage to achieve ferroelectric modulation,which eliminates the need for gate *** applying a very small strain(0.01%),the St-FeFET can achieve a maximum on-off current ratio of 1250%and realizes a gauge factor(GF)of 1.19×10^(6),which is much higher than that of conventional strain *** work proposes a new method for realizing highly sensitive strain sensors and presents innovative approaches to the operation methods of ferroelectric field-effect transistors as well as potential applications for coupling of strain sensors and various devices across different fields.

关键词： ferroelectric field-effect transistors piezotronics [Pb(Mg_(1/3)Nb_(2/3))O_(3)]_((1-x)^(-))[PbTiO_(3)]_(x)(PMN-PT) strain sensors

Large Deviations for a Critical Galton-Watson Branching Process

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Acta Mathematicae Applicatae Sinica 2024年

作者： Dou-dou LI wan-lin SHI Mei ZHANG College of Statistics and Data science Faculty of Science Beijing University of Technology Laboratory of Mathematics and Complex systems (Ministry of Education) School of Mathematical SciencesBeijing Normal University Department of Mathematics and Physics North China Electric Power University

In this paper, a critical Galton-Watson branching process{Zn}is considered. Large deviation rates of SZn:=∑i=1ZnXiare obtained, where{Xi, i≥1}is a sequence of independent and identically distributed random variables and X1is in the domain of attraction of an α-stable law with α∈(0, 2). One shall see that the convergence rate is determined by the tail index of X1and the variance of Z1. Our results can be compared with those ones of the supercritical case.

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Working condition recognition of sucker rod pumping system based on 4-segment time-frequency signature matrix and deep learning

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Petroleum science 2024年第1期21卷 641-653页

作者： Yun-Peng He Hai-Bo Cheng Peng Zeng Chuan-Zhi Zang Qing-Wei Dong Guang-Xi wan Xiao-Ting Dong State Key Laboratory of Robotics Shenyang Institute of AutomationChinese Academy of SciencesShenyang 110016LiaoningChina Key Laboratory of Networked Control systems Chinese Academy of SciencesShenyang 110016LiaoningChina Institutes for Robotics and Intelligent Manufacturing Chinese Academy of SciencesShenyang 110169LiaoningChina University of chinese academy of sciences Beijing100049China School of Artifcial Intelligence Shenyang University of TechnologyShenyang 110870LiaoningChina

High-precision and real-time diagnosis of sucker rod pumping system(SRPS)is important for quickly mastering oil well *** learning-based method for classifying the dynamometer card(DC)of oil wells is an efficient diagnosis ***,the input of the DC as a two-dimensional image into the deep learning framework suffers from low feature utilization and high computational ***,different SRPSs in an oil field have various system parameters,and the same SRPS generates different DCs at different ***,there is heterogeneity in field data,which can dramatically impair the diagnostic *** solve the above problems,a working condition recognition method based on 4-segment time-frequency signature matrix(4S-TFSM)and deep learning is presented in this ***,the 4-segment time-frequency signature(4S-TFS)method that can reduce the computing power requirements is proposed for feature extraction of DC ***,the 4S-TFSM is constructed by relative normalization and matrix calculation to synthesize the features of multiple data and solve the problem of data ***,a convolutional neural network(CNN),one of the deep learning frameworks,is used to determine the functioning conditions based on the *** on field data verify that the proposed diagnostic method based on 4S-TFSM and CNN(4S-TFSM-CNN)can significantly improve the accuracy of working condition recognition with lower computational *** the best of our knowledge,this is the first work to discuss the effect of data heterogeneity on the working condition recognition performance of SRPS.

关键词： Sucker-rod pumping system Dynamometer card Working condition recognition Deep learning Time-frequency signature Time-frequency signature matrix

Establishing cell suitability for high-level production of licorice triterpenoids in yeast

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Acta Pharmaceutica Sinica B 2024年第9期14卷 4134-4148页

作者： Wentao Sun Shengtong wan Chuyan Liu Ruwen wang Haocheng Zhang Lei Qin Runming wang Bo Lv Chun Li Department of Chemical Engineering Tsinghua UniversityBeijing 100084China Key Laboratory of Medical Molecule science and Pharmaceutics Engineering Ministry of Industry and Information TechnologyInstitute of Biochemical EngineeringSchool of Chemistry and Chemical EngineeringBeijing Institute of TechnologyBeijing 100081China The University of Chicago ChicagoIL 60637USA Key Lab for Industrial Biocatalysis Ministry of EducationTsinghua UniversityBeijing 100084China Center for Synthetic and systems Biology Tsinghua UniversityBeijing 100084China Institute of Biopharmaceutical and Health Engineering Tsinghua Shenzhen International Graduate SchoolTsinghua UniversityShenzhen 518055China

Yeast has been an indispensable host for synthesizing complex plant-derived naturalcompounds, yet the yields remained largely constrained. This limitation mainly arises from overlookingthe importance of cell and pathway suitability during the optimization of enzymes and pathways. Herein,beyond conventional enzyme engineering, we dissected metabolic suitability with a framework forsimultaneously augmenting cofactors and carbon flux to enhance the biosynthesis of heterogenoustriterpenoids. We further developed phospholipid microenvironment engineering strategies, dramaticallyimproving yeast’s suitability for the high performance of endoplasmic reticulum (ER)-localized, ratelimitingplant P450s. Combining metabolic and microenvironment suitability by manipulating only threegenes, NHMGR (NADH-dependent HMG-CoA reductase), SIP4 (a DNA-binding transcription factor)andGPP1 (Glycerol-1-phosphate phosphohydrolase 1), we enabled the high-level production of 4.92 g/L rarelicorice triterpenoids derived from consecutive oxidation of b-amyrin by two P450 enzymes afterfermentation optimization. This production holds substantial commercial value, highlighting the criticalrole of establishing cell suitability in enhancing triterpenoid biosynthesis and offering a versatileframework applicable to various plant natural product biosynthetic pathways.

关键词： Cell suitability Phospholipid microenvironment Cytochrome P450 Triterpenoids Saccharomyces cerevisiae

Anisotropic Variation Law of Rock Permeability with the Burial Depth of Limestone

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Acta Geologica Sinica(English Edition) 2003年第1期77卷 125-128页

作者： TIAN Kaiming, wan Li and TIAN Jiping Department of Water Resources and Environmental science, china University of Geosciences,27 Xueyuan Road, beijing 100083, Department of Computer sciences, Guangzhou University, Guangzhou, Guangdong 510091 china Univ Geosci Dept Water Resources & Environm Sci Beijing 100083 Peoples R China Guangzhou Univ Dept Comp Sci Guangzhou 510091 Guangdong Peoples R China

Permeability tensors of both macrofracture and microfracture systems weremeasured progressively along the depth of limestone formations at severed sites. It was found thatthe principal permeability values K_x, K_y and K_z in these permeability tensors all decreasesimultaneously and logarithmically with depth. However, the limestone aquifers are composed of anupper region where the larger permeability ellipsoid is upright or prolate and characterized byK_z>K_x and K_z>K_y, a transitional zone, and a lower zone whose smaller permeability ellipsoid ishorizontal or oblate and characterized by K_z>K_x and K_z>K_y. The inversion of the permeabilityellipsoids in direction indicates that the anisotropy of rock permeability with the depth oflimestone formations has evidently changed. The anisotropic variation law of permeability tensors ina macrofracture system displays a similar pattern with that in a microfracture system. It is nextto impossible to examine the rock permeability tensor of the aquifer just by measuring the hydraulicparameters of macrofracture system directly, unless the limestone aquifer is exposed on or near theearth's surface. Therefore, the permeability tensors of a macrofracture system at any depth may beindirectly and roughly determined from the gaugeable permeability tensors of the microfracturesystem by conversion. This anisotropic variation law of rock permeability with depth is of greatsignificance in the study of three-dimensional fracture water flow the huge carbonate formations andin the research on the conditions of karst development and karst distribution.

关键词： macrofracture system microfracture system permeability tensor permeability ellipsoid

NEW DESIGN AND ANALYSIS OF FINITE DIFFERENCE DOMAIN DECOMPOSITION ALGORITHM FOR THE TWO-DIMENSIONAL HEAT EQUATION

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Journal of systems science & Complexity 2010年第2期23卷 403-412页

作者： Zhengsu wan Baolin ZHANG Guangnan CHENG Department of Mathematics Itunan Institute of Science and Technology Yueyang 414006 China Laboratory of Computational Physics Institute of Applied Physics and Computational Mathematics Beijing100088 China.

It is presented in this paper that the new design and its analysis of finite difference domain decomposition algorithms for the two-dimensional heat equation, and the numerical results have shown the stability and accuracy of the algorithms, where SauFyev asymmetric schemes have been used at the interface points. The Algorithm II in this paper has further extended those developed by Dawson and the others, Zhang and Shen.

关键词： Domain decomposition finite difference Saul'yev schemes two-dimensional heat equation

The New Architecture with Time-Spatial Consistency for 5G Networks

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china Communications 2016年第1期13卷 68-79页

作者： SUN Zhennian XU Xu CHAI Xiaomeng ZHANG Tianyu TIAN Lin ZHANG Zhongshan beijing Engineering and Technology Center for Convergence Networks and Ubiquitous Services University of Science and Technology Beijing (USTB) Beijing China 100083 NEC Laboratories china (NLC) Beijing 100084 China Institute of Computing Technology Chinese Academy of Sciences Beijing China 100190

While operators have started deploying fourth generation(4G) wireless communication systems,which could provide up to1 Gbps downlink peak data rate,the improved system capacity is still insufficient to meet the drastically increasing demand of mobile users over the next *** main causes of the above-mentioned phenomenon include the following two aspects:1) the growth rate of the network capacity is far below that of user's demand,and 2) the relatively deterministic wireless access network(wan) architecture in the existing systems cannot accommodate the prominent increase of mobile traffic with space-time domain *** order to address the above-mentioned challenges,we investigate the time-spatial consistency architecture for the future wan,whilst emphasizing the critical roles of some spectral-efficient techniques such as Massive multiple-input multiple-output(MIMO),full-duplex(FD)operation and heterogeneous networks(HetNets).Furthermore,the energy efficiency(EE)of the HetNets under the proposed architecture is also evaluated,showing that the proposed user-selected uplink power control algorithm outperforms the traditional stochastic-scheduling strategy in terms of both capacity and EE in a two-tier *** other critical issues,including the tidal effect,the temporal failure owing to the instantaneously increased traffic,and the network wide load-balancing problem,etc.,are also anticipated to be addressed in the proposed architecture.(Abstract)

关键词： wireless access network spectral efficiency energy efficiency super base station heterogeneous network

Human multi-drug resistant hepatocellular carcinoma induced in nude mice by B-ultrasonographically-directed orthotopic implantation:a new experimental model

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Hepatobiliary & Pancreatic Diseases International 2007年第4期6卷 393-398页

作者： Lei Ding,Xiao-Ping Chen,Zhi-Wei Zhang,Kai Jing and wan-Guang Zhang Hepatic Surgery Center,Affiliated Tongji Hospital,Tongji Medical College,Huazhong University of science and Technology,Wuhan 430030,china Department of Oncology Center,beijing Shijitan Hospital,beijing 100038,china Hepatic Surgery Center Affiliated Tongji Hospital Tongji Medical College Huazhong University of Science and Technology Wuhan 430030 China. dinglei1005@***

BACKGROUND:Present studies on the reversal of multi-drug resistance(MDR) are almost entirely limited to in vitro systems,and are seldom carried out in vivo. In order to study MDR under the in vivo situation,a MDR cell strain was used to establish a model in nude mice via orthotopic implantation directed by B-ultrasonography. This model is expected to provide a good platform for evaluating strategies to reverse the phenomenon of primary hepatocellular carcinoma(HCC) MDR. METHODS:An orthotopic MDR1 hepatoma was obtained by injecting the cell lines HepG2 and HepG2/ADM subserosally into the liver of nude mice(10 control and 20 MDR mice). The injections were made under B-ultrasonographic direction. Ultrasonography and laparotomy were used to assess tumor growth,and the long chain PCR technique was applied to sequence the MDR1 gene from multi-drug resistant human HCC cells,HepG2/ADM,and corresponding implanted tumor tissues. Furthermore,MDR1 mRNA and P-gp protein expression were evaluated by reverse transcriptase-polymerase chain reaction(RT-PCR),Western blotting,and immunohistochemical methods. RESULTS:The success rates of tumor implantation and induction of MDR were 100%(30/30) and 95%(19/20),respectively. The 3.8kbp MDR1 gene band was detected from the HepG2/ADM cell line and the correspondingimplanted tumor tissues,and the MDR1 gene sequence coincided with that reported in GenBank. The expressions of MDR1 mRNA and P-gp protein in MDR mice were significantly higher than those in the control group. There was a significant difference in P-gp protein expression between MDR and control mice. CONCLUSION:A MDR model has been successfully established in nude mice via orthotopic implantation of multi-drug resistant human HCC cells directed by ultrasonography.

关键词： nude mice orthotopic implantation carcinoma,hepatocellular drug resistance,multiple