检索结果-南通市图书馆

Sum-Rate Maximization in Active RIS-Assisted Multi-Antenna WPCN

在线全文

学校读者我要写书评

暂无评论

China Communications 2024年第6期21卷 23-39页

作者： Jiang Jie Lyu Bin chen pengcheng Yang Zhen School of Communications and Information Engineering Nanjing University of Posts and TelecommunicationsNanjing 210003China Jiangsu Provincial Key Laboratory of Photonic and Electronic Materials Sciences and Technology Nanjing UniversityNanjing 210003China

In this paper,we propose an active reconfigurable intelligent surface(RIS)enabled hybrid relaying scheme for a multi-antenna wireless powered communication network(WPCN),where the active RIS is employed to assist both wireless energy transfer(WET)from the power station(PS)to energyconstrained users and wireless information transmission(WIT)from users to the receiving station(RS).For further performance enhancement,we propose to employ both transmit beamforming at the PS and receive beamforming at the *** formulate a sumrate maximization problem by jointly optimizing the RIS phase shifts and amplitude reflection coefficients for both the WET and the WIT,transmit and receive beamforming vectors,and network resource *** solve this non-convex problem,we propose an efficient alternating optimization algorithm with the linear minimum mean squared error criterion,semidefinite relaxation(SDR)and successive convex approximation ***,the tightness of applying the SDR is *** results demonstrate that our proposed scheme with 10 reflecting elements(REs)and 4 antennas can achieve 17.78%and 415.48%performance gains compared to the single-antenna scheme with 10 REs and passive RIS scheme with 100 REs,respectively.

关键词： active reconfigurable intelligent surface beamforming sum-rate maximization wireless powered communication network

Pseudomonas mendocina LYX:A novel aerobic bacterium with advantage of removing nitrate high effectively by assimilation and dissimilation simultaneously

在线全文

学校读者我要写书评

暂无评论

Frontiers of Environmental Science & Engineering 2021年第4期15卷 131-140页

作者： Yuxin Li Jiayin Ling pengcheng chen Jinliang chen Ruizhi Dai Jinsong Liao Jiejing Yu Yanbin Xu School of Environmental Science and Engineering Guangdong University of TechnologyGuangzhou510006China Guangdong Yikangsheng Environmental Protection Science and Technology Company Yunfu527300China Analysis and Test Center Guangdong University of TechnologyGuangzhou510006China

The problem of nitrate accumulation in aerobic tank and total nitrogen excessive discharge in effluent was very common in traditional livestock and poultry farming wastewater treatment systems owing to the lengthy process flow and low process control level.A strain LYX of aerobic bacterium was isolated from the activated sludge of a wastewater treatment system in a pig farm,which could remove nitrate effectively in aerobic tank and was identified Pseudomonas mendocina by 16S rRNA *** the condition of nitrate as the sole nitrogen source,this strain removed over 90%of NO_(3)^(−)-N with an initial concentration of 110 mg/L under aerobic conditions within 48 *** them,37.9%of NO_(3)^(−)-N was assimilated into Bio-N,about 51.9%was reduced to gaseous nitrogen and less than 0.5%of nitrogen was replaced by NO_(3)^(−)-N and NH_(4)^(+)-N,9.7%NO_(3)^(−)-N remained in the effluent at the *** the same time,four key genes(napA,nirK,norB and nosZ)related to nitrate nitrogen removal were expressed during the denitrification process of *** LYX,in which the transcription level of the indicator genes of this aerobic denitrifying bacterium(napA)was the *** addition,it was found with the 15N tracer technique that inoculation of this strain on sludge increased the amount of nitrogen loss from 9.26 nmol N/(g·h)to 23.835 nmol N/(g·h).Therefore,*** LYX is a potential bioagent for advanced nitrogen removal by assimilating and reducing nitrate simultaneously in aerobic tanks.

关键词： Pseudomonas mendocina Aerobic nitrate removal ^(15)N tracing technique Denitrification assimilatively and disimilatively Aerobic denitrifying genes

Efect of the Gad system on Actinobacillus succinogenes during acid stress

在线全文

学校读者我要写书评

暂无评论

Systems Microbiology and Biomanufacturing 2022年第1期2卷 177-185页

作者： Chunmei chen Qun Zhang Junzhu Qian Dan Wu pengcheng chen Pu Zheng The Key Laboratory of Industrial Biotechnology Ministry of EducationSchool of BiotechnologyJiangnan UniversityWuxi 214122China

The glutamate decarboxylase(Gad)system is an important amino acid-dependent acid resistance system commonly found in *** succinogenes is one of the best natural producers of succinic acid(SA)but lacks glutamate *** study assessed the efects of Gad system introduction into *** recombinant strains gadB-SW and gadBC-SW were constructed by heterologous expression of gadB alone,or gadB together with gadC,*** 1.0 and 1.5 h of acid stress at pH 4.6,cell survival of gadBC-SW was greater than *** growth of gadB-SW and gadBC-SW was both afected by the expression of heterologous proteins and byγ-aminobutyric acid,with gadBC-SW growth reduced at a neutral *** production in acidic conditions was evaluated by a shake fask and by 3-L bioreactor *** results showed gadBC-SW to increase SA production by 8.4%in shake fask compared to the parent strain,*** a 3-L bioreactor batch fermentation under acidic environment,the highest conversion rate of sugar to SA was observed for gadBC-SW,reaching 96%.However,SA concentration by gadBC-SW was only 47 g/L and 31 g/L at pH 6.5 and pH 6.0,*** summary,the introduction of heterologous gadB and gadC into *** not only improved acid tolerance but also infuenced the synthesis of SA and added a metabolic burden.

关键词： Actinobacillus succinogenes Acid stress Glutamate decarboxylase Succinic acid Glutamate

Orientation of molecular interface dipole on metal surface investigated by noncontact atomic force microscopy

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Chinese Science Bulletin 2013年第30期58卷 3630-3635页

作者： YUAN BingKai chen pengcheng ZHANG Jun chenG ZhiHai QIU XiaoHui WANG chen National Center for Nanoscience and Technology

We investigated the orientations of interface dipole moments of individual non-planar titanyl phthalocyanine(TiOPc)molecules on Cu(111)and Cu(100)substrates using scanning tunneling microscope(STM)and noncontact atomic force microscope(NC-AFM).The dipole moment orientations corresponding to two different configurations of individual TiOPc molecules were determined *** correlation between the actual molecular structures and the corresponding STM topographies is proposed based on the sub-molecular resolution imaging and local contact potential difference(LCPD)*** with the pristine substrate,the LCPD shift due to the adsorption of non-planar molecule is dependent on the permanent molecular dipole,the charge transfer between the surface and the molecule,and the molecular *** work would shed light on tailoring interfacial electronic properties and controlling local physical properties via polar molecule adsorption.

关键词：原子力显微镜分子结构非接触式金属表面偶极子界面 Cu(100) Cu(111)

WoT/SDN:Web of Things Architecture Using SDN

在线全文

学校读者我要写书评

暂无评论

China Communications 2015年第11期12卷 177-187页

作者： QIU Xiaofeng LIU Wenmao GAO Teng HE Xinxin WEN Xutao chen pengcheng Beijing Key Laboratory of Network System Architecture and Convergence BUPT NSFocus Security Labs

Wo T(Web of Things) integrates smart devices into Web by reusing and extending Web standards. While Web technology makes the developers' job easier,it faces security,management and efficiency challenges. We propose Wo T/SDN,the architecture of resource oriented Wo T built on SDN(Software Defined Network),in which applications could be developed through resource subscription and Mashup with the programmability provided by SDN. The key components are designed,including Security and Management Controller(SMC),various atomic services and resource subscription syntax. Three applications covering device management,data access and security protection are demonstrated. Compared to traditional resource-oriented Wo T systems,our test results show that SDN,with its logically centralized control capability and awareness of flow forwarding,provides new opportunity to improve performance,simplify management and enhance security for Wo T.

关键词： Wo T SDN Controller

Enhanced thermostability and catalytic efciency of glucose oxidase in Pichia Pastoris

在线全文

学校读者我要写书评

暂无评论

Systems Microbiology and Biomanufacturing 2022年第2期2卷 296-304页

作者： Hanlei Zhou Pu Zheng pengcheng chen Xiaowei Yu Dan Wu The Key Laboratory of Industrial Biotechnology Ministry of EducationSchool of BiotechnologyJiangnan UniversityWuxi 214122China

Glucose oxidase(GOD)has many practical applications,but its poor thermostability limits its broader *** this research,three primary mutants of wild-type GOD were designed using rational mutagenesis,and the GODm mutant was constructed by combinatorial *** expression,purifcation,and enzymatic properties of the mutants were *** specifc enzyme activity of GODm was 2.10-fold higher than that of wild type,and the(k_(cat)/K_(m))value was increased by *** treatment at 55℃for 3 h,GODm retained 37.5%of its enzymatic activity,and the half-life(t_(1/2))of GODm at 55℃and 65℃was 2.28-fold and 3.36-fold higher than that of wild type,*** analyzing the three-dimensional structure of wild type and the GODm mutant,it was found that T30V formed a new hydrogen bond with FAD and strengthened the hydrophobic interaction,D315K optimized the surface electrostatic interaction,and A162T improved the efciency of the electron ***,a novel mutant with improved thermostability and catalytic efciency was obtained in this research.

关键词： Glucose oxidase Pichia pastoris Thermostability Catalytic efciency Rational mutagenesis

Periodically poled LiNbO3 crystals from 1D and 2D to 3D

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Science China(Technological Sciences) 2020年第7期63卷 1110-1126页

作者： WANG TianXin chen pengcheng XU Chuan ZHANG Yong WEI DunZhao HU XiaoPeng ZHAO Gang XIAO Min ZHU ShiNing National Laboratory of Solid State Microstructures College of Engineering and Applied Sciencesand School of Physicsand Collaborative Innovation Center of Advanced MicrostructuresNanjing UniversityNanjing 210093China

A periodically-poled LiNbO3(PPLN) crystal features space-dependent second-order nonlinear coefficients, which is one of the most important materials to effectively control nonlinear optical interactions through quasi-phase matching(QPM). By using electric-field poling method, 1D and 2D PPLN crystals have been successfully fabricated for laser frequency conversion, quantum light sources, nonlinear beam shaping and nonlinear optical imaging. Recently, femtosecond laser engineering technique is utilized to prepare 3D domain structures inside LiNbO3 crystal, which provides a promising platform to control nonlinear interacting waves in 3D configuration. After 40 years of developments, PPLN crystals still have exciting prospects in fundamental researches and practical applications for integrated photonic chip, quantum information processing,and so on.

关键词： periodically-poled LiNbO3 quasi-phase matching nonlinear optics

Discovery and characterization of naturally occurring covalent inhibitors of SARS-CoV-2 M^(pro)from the antiviral herb Ephedra

在线全文

学校读者我要写书评

暂无评论

Chinese Journal of Natural Medicines 2024年第9期22卷 797-807页

作者： HU Qing ZHANG Yiwen chen pengcheng ZHANG Yani ZHU Guanghao LIU Wei WANG Chaoran ZHENG Shuilian SHEN Nonger WANG Haonan HUANG Ping GE Guangbo Center for Clinical Pharmacy Cancer CenterDepartment of PharmacyZhejiang Provincial People’s Hospital(Affiliated People’s Hospital)Hangzhou Medical CollegeHangzhou 310014China Shanghai Frontiers Science Center of TCM Chemical Biology Institute of Interdisciplinary Integrative Medicine ResearchShanghai University of Traditional Chinese MedicineShanghai 201203China Shuguang Hospital Affiliated to Shanghai University of Traditional Chinese Medicine Shanghai 200021China Dalian Institute of Chemical Physics Chinese Academy of SciencesDalian 116023China

The Chinese herb Ephedra(also known as Mahuang)has been extensively utilized for the prevention and treatment of coronavirus-induced diseases,including coronavirus disease 2019(COVID-19).However,the specific anti-SARS-CoV-2 compounds and mechanisms have not been fully *** main protease(M^(pro))of SARS-CoV-2 is a highly conserved enzyme responsible for proteolytic processing during the viral life cycle,making it a critical target for the development of antiviral *** study aimed to identify naturally occurring covalent inhibitors of SARS-CoV-2 M^(pro)from Ephedra and to investigate their covalent binding *** results demonstrated that the non-alkaloid fraction of Ephedra(ENA)exhibited a potent inhibitory effect against the SARS-CoV-2 M^(pro)effect,whereas the alkaloid fraction did ***,the chemical constituents in ENA were identified,and the major constituents'anti-SARS-CoV-2 M^(pro)effects were *** the tested constituents,herbacetin(HE)and gallic acid(GA)were found to inhibit SARS-CoV-2 M^(pro)in a time-and dose-dependent *** combination displayed a significant synergistic effect on this key ***,various techniques,including inhibition kinetic assays,chemoproteomic methods,and molecular dynamics simulations,were employed to further elucidate the synergistic anti-M^(pro)mechanisms of the combination of HE and ***,this study deciphers the naturally occurring covalent inhibitors of SARS-CoV-2 M^(pro)from Ephedra and characterizes their synergistic anti-M^(pro)synergistic effect,providing robust evidence to support the anti-coronavirus efficacy of Ephedra.

关键词： Main protease Ephedra Ephedra non-alkaloid fraction Covalent inhibitors Synergistic effect

Quasi-phase-matching-division multiplexing holography in a three-dimensional nonlinear photonic crystal

在线全文

学校读者我要写书评

暂无评论

Light(Science & Applications) 2021年第8期10卷 1520-1526页

作者： pengcheng chen Chaowei Wang Dunzhao Wei Yanlei Hu Xiaoyi Xu Jiawen Li Dong Wu Jianan Ma Shengyun Ji Leran Zhang Liqun Xu Tianxin Wang Chuan Xu Jiaru Chu Shining Zhu Min Xiao Yong Zhang National Laboratory of Solid State Microstructures College of Engineering and Applied SciencesSchool of Physicsand Collaborative Innovation Center of Advanced MicrostruauresNanjing UniversityNanjing 210093China. Hefei National Laboratory for Physical Sciences at the Microscale and CAS Key Laboratory of Mechanical Behavior and Design of Materials Department of Precision Machinery and Precision InstrumentationUniversity of Science and Technology of ChinaHefei 230026China. Department of Physics University of ArkansasFayettevilleAR 72701USA

Nonlinear holography has recently emerged as a novel tool to reconstruct the encoded information at a new wavelength,which has important applications in optical display and optical ***,this scheme still struggles with low conversion efficiency and ineffective *** this work,we demonstrate a quasi-phasematching(QPM)-division multiplexing holography in a three-dimensional(3D)nonlinear photonic crystal(NPC).3D NPC works as a nonlinear hologram,in which multiple images are distributed into different Ewald spheres in reciprocal *** reciprocal vectors locating in a given Ewald sphere are capable of fulfilling the complete QPM conditions for the high-efficiency reconstruction of the target image at the second-harmonic(SH)*** can easily switch the reconstructed SH images by changing the QPM *** multiplexing capacity is scalable with the period number of 3D *** work provides a promising strategy to achieve highly efficient nonlinear multiplexing holography for high-security and high-density storage of optical information.

关键词： wave nonlinear matching