检索结果-南通市图书馆

Existence of long-range magnetic order in Heisenberg spin nanoribbons with edge modification

在线全文

学校读者我要写书评

暂无评论

Communications in Theoretical Physics 2024年第7期76卷 134-144页

作者： Da-cheng Ma Ling-yi Cui Chu-xiao Sun Xiao-dan Chi Zheng-Nan XianYu An Du College of Science Northeastern UniversityShenyang 110819China Department of Basic Science Dalian Naval AcademyDalian 116018China Department of Physics College of SciencesShenyang University of Chemical TechnologyShenyang 110142China National Frontiers Science Center for Industrial Intelligence and Systems Optimization Northeastern UniversityChina Key Laboratory of Data Analytics and Optimization for Smart Industry(Northeastern University) Ministry of EducationChina

Long-range magnetic order appears on a side decorated Heisenberg spin nanoribbon at nonzero temperature,although no spontaneous magnetization exists in a one-or two-dimensional isotropic Heisenberg model at any nonzero temperature according to the Mermin-Wagner *** use of the spin Green's function method,we calculated the magnetizations of Heisenberg nanoribbons decorated by side spins with single-ion anisotropy and found that the system exhibits a nonzero transition temperature,whether the decorated edge spins of the system link together or separate from each *** the width of the nanoribbon achieves infinite limit,the transition temperatures of the system tend to the same finite constant eventually whether one edge or both edges are decorated by side spins in the *** results reveal that the magnetism of a low-dimensional spin system is different from that of a threedimensional spin *** the single-ion anisotropy of edge spins in a Heisenberg spin nanoribbon can be modulated by an electric field experimentally,various useful long-range magnetic orders of the system can be *** work can provide a detailed theoretical basis for designing and fabricating next-generation low-dimensional magnetic random-access memory.

关键词： Nanoribbon magnetic anisotropy long-range magnetic order Heisenberg model transition temperature

Impact of non-ideal UE hardware on cell-free massive MIMO network with centralized operation

在线全文

学校读者我要写书评

暂无评论

Science China(Information Sciences) 2024年第4期67卷 255-271页

作者： Ning LI Pingzhi FAN Institute of Mobile Communications Southwest Jiaotong University

This paper investigates the impact of non-ideal user equipment(UE) hardware on a cell-free(CF) massive MIMO(mMIMO) network with centralized operation under spatially correlated channels. The minimum mean-squared error(MMSE) estimator can be derived with the help of the generic non-ideal UE hardware model. It is demonstrated that even if the effective signal-to-noise ratio approaches infinity, pilot contamination and imperfect hardware can cause a non-zero estimation error floor. After that, a lower bound is determined for the ergodic uplink capacity of the centralized CF mMIMO network under non-ideal UE hardware. Moreover, the optimal receive combining vector is obtained to maximize the uplink spectral efficiency(SE). The maximum ratio(MR) and regularized zero-forcing(RZF) combining schemes are offered as alternatives in light of the computational complexity of the MMSE receiver. Comparing the RZF to the MMSE scheme under different levels of hardware impairments, our findings indicate that the RZF receiver suffers a negligible loss in total SE. For MR combining, a novel closed-form uplink achievable SE expression is obtained based on the MMSE estimator and the use-and-then-forget bounding technique. This expression gives vital insights into the achievable uplink performance with UE hardware impairments. Besides, for various hardware impairment factors, the impact of pilot sequence length on average sum SE is disclosed for different receive combining schemes. To increase the overall SE of the max-min fairness scheme, a heuristic fractional power control scheme with UE hardware impairments is developed, which can essentially avoid sacrificing the SE of other UEs while maximizing the SE of the unluckiest UE in the whole network. Finally,our theoretical performance analysis and power control algorithm are validated by simulation results, and fundamental design guidelines are provided for selecting hardware satisfying the practical UE requirements.

关键词： cell-free massive MIMO centralized operation spatially correlated channels hardware impairments channel estimation uplink spectral efficiency optimal receive combining pilot length design fractional power control

Microfluidic thermotaxic selection of highlymotile sperm and in vitro fertilization

在线全文

同方期刊数据库

学校读者我要写书评

暂无评论

Bio-Design and Manufacturing 2024年第5期7卷 687-700页

作者： Sihan Chen Jiemin Chen Zihan Qin Jibo Wang Yuwen Wang Rong Liu Wen Zhao Ming Zhang Yuanzhen Zhang Mengcheng Luo Pu Chen Tissue Engineering and Organ Manufacturing(TEOM)Lab Department of Biomedical EngineeringTaiKang Medical School(School of Basic Medical Sciences)Wuhan UniversityWuhan 430071China Hubei Provincial Key Laboratory of Developmentally Originated Disease TaiKangMedical School(School of Basic Medical Sciences)Wuhan UniversityWuhan 430071China Reproductive Medicine Center Zhongnan Hospital of Wuhan UniversityWuhan 430071China TaiKang Center for Life and Medical Sciences Wuhan UniversityWuhan 430071China

The selection of the most motile and functionally competent sperm is an essential basis for in vitro fertilization(IVF)and normal embryonic *** adopted clinical approaches for sperm sample processing intensely rely on centrifugation and wash steps that may induce mechanical damage and oxidative stress to *** a few microfluidic sperm sorting devices may avoid these adverse effects by exploiting intrinsic guidance mechanisms of sperm swimming,none of these approaches have been fully validated by clinical-grade assessment *** this study,a microfluidic sperm sorting device that enables the selection of highly motile and functional sperm via their intrinsic thermotaxis is *** by the temperature microenvironment in the fallopian tube during natural sperm selection,a microfluidic device with controllable temperature gradients along the sperm separation channel was designed and *** study investigated the optimal temperature conditions for human sperm selection and fully characterized thermotaxis-selected sperm with 45 human sperm *** indicated that a temperature range of 35–36.5℃along the separation channel significantly improves human sperm motility rate((85.25±6.28)%vs.(60.72±1.37)%;P=0.0484),increases normal sperm morphology rate((16.42±1.43)%vs.(12.55±0.88)%;P<0.0001),and reduces DNA fragmentation((7.44±0.79)%vs.(10.36±0.72)%;P=0.0485)compared to the nonthermotaxis *** thermotaxis is species-specific,and selected mouse sperm displayed the highest motility in response to a temperature range of 36–37.5℃ along the separation ***,IVF experiments indicated that the selected sperm permitted an increased fertilization rate and improved embryonic development from zygote to *** microfluidic thermotaxic selection approach will be translated into clinical practice to improve the IVF success rate for patients with oligozoospermia and asthenozoospermia.

关键词： Microfluidic device Thermotaxis Sperm sorting Assisted reproductive technology In vitro fertilization

Promoted monolithic perovskite/organic tandem solar cells through elaborate manipulation of light transmission and carrier tunneling in interconnect junction

在线全文

学校读者我要写书评

暂无评论

Science China Chemistry 2024年第9期67卷 3131-3139页

作者： Rongbo Wang Jiawei Zhang Juntao Zhao Ya Wang Yi Ding Ying Zhao Xiaodan Zhang Guofu Hou Institute of Photoelectronic Thin Film Devices and Technology Renewable Energy Conversion and Storage CenterSolar Energy Conversion CenterNankai UniversityTianjin 300350China Key Laboratory of Photoelectronic Thin Film Devices and Technology of Tianjin Tianjin 300350China Engineering Research Center of Thin Film Photoelectronic Technology of Ministry of Education Tianjin 300350China State Key Laboratory of Photovoltaic Materials and Solar Cells Tianjin 300350China

Monolithic perovskite/organic tandem solar cells(TSCs)have emerged as promising thin film solar *** is recognized that interconnect junction plays a pivotal role in tandem ***,wide bandgap Cs_(0.25)FA_(0.75)Pb(I_(0.6)Br_(0.4))_(3)perovskite top-cell and narrow bandgap PM6:Y6:PC_(61)BM ternary organic bottom-cell were integrated in this study with several kinds of thin metal interconnect layers,which provides feasibility to elaborately manipulate light transmission and carrier tunneling process in interconnect *** is confirmed that,in comparison with Au,employing an Ag interconnect layer elevates integrated transmittance of light in longer wavelength regions,mainly because of the alleviated screening effect with a lower free electron concentration,which offers sufficient light harvest for the ***,established energy barriers with moderate height afford convenient extraction and recombination for both holes and ***,the performance of TSCs is promoted ***,an innovative Ag/Au double interconnect layer is proposed accordingly,which can preserve exceptional conductivity and light transmission and further reduce barrier height,especially for hole tunneling,by optimizing the band alignment between the interconnect layer and ***,the monolithic perovskite/organic TSC with a striking efficiency of 23.26% is *** a word,this study can pave a general approach toward high-performance TSCs integration.

关键词： tandem solar cells band alignment perovskite organic solar cells interconnect junction

Enhanced electrochemical performance of Li_(1.3)Al_(0.3)Ti_(1.7)(PO_(4))_(3) solid electrolyte by anion doping

在线全文

学校读者我要写书评

暂无评论

Nano Research 2024年第3期17卷 1465-1472页

作者： Jingrui Kang Xu Guo Rui Gu Honglei Hao Yi Tang Jiahui Wang Li Jin Hongfei Li Xiaoyong Wei Electronic Materials Research Laboratory Key Laboratory of the Ministry of Education&International Center for Dielectric ResearchSchool of Electronic and Information EngineeringXi’an Jiaotong UniversityXi’an 710049China School of Energy and Materials Shanghai Key Laboratory of Engineering Materials Application and EvaluationShanghai Polytechnic UniversityShanghai 201209China

Nowadays,the majority of the studies on the substitution are focused on cations(such as Y^(3+),Ti^(4+),P^(5+),etc.)in Li_(1.3)Al_(0.3)Ti_(1.7)(PO_(4))_(3)(LATP),while there are few studies on the substitution of anion O^(2-).In this work,the modified LATP with a series of LiCl(LATPClx,x=0.1,0.2,0.3,0.4)additives is prepared to enhance ionic *** successful introduction of Cl-makes the length of the c axis decrease from 20.822(2)to 20.792(1)Å,and the bulk conductivity of 2.13×10^(-3) S·cm^(-1) is achieved in LATPCl_(0.3).Moreover,the Al/Ti-O1/Cl1 and Al/Ti-O_(2)/Cl_(2) distance decrease,while the Li1-O_(2)/Cl_(2) distance *** ions migrate more easily in the nanochannel of *** addition,the LiCl additive increases the relative density and the grain boundary conductivity of LATPClx ***,a higher ionic conductivity of 2.12×10^(–4) S·cm^(-1) and a low activation energy of 0.30 eV are obtained in LATPCl_(0.3).Correspondingly,the symmetric cell exhibits a low overpotential of±50 mV for over 200 h in LATPCl_(0.3).The solid-state Li|LATPCl_(0.3)|NCM811(NCM811=LiNi0.8Co0.1Mn0.1O_(2))battery exhibits high initial capacity 185.1 mAh·g^(-1) with a capacity retention rate of 95.4%after 100 cycles at 0.5 *** result suggests that LiCl additive is an effective strategy to promote electrochemical properties of LATP solid electrolyte and can be considered for reference to other inorganic solid electrolytes systems.

关键词： Li_(1.3)Al_(0.3)Ti_(1.7)(PO_(4))_(3)(LATP)solid electrolyte anion doping ionic conductivity cyclic performance

Characteristics of long-distance mobile mRNAs from shoot to root in grafted plant species

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

Horticultural Plant Journal 2024年第1期10卷 25-37页

作者： Mengmeng Fu Zhen Xu Huaying Ma Yifan Hao Ji Tian Yi Wang Xinzhong Zhang Xuefeng Xu Zhenhai Han Ting Wu College of Horticulture China Agricultural UniversityBeijing 100193China Plant Science and Technology College Beijing University of AgricultureBeijing 102206China

Thousands of long-distance mobile mRNAs were identified from different grafting systems,based on high-throughput sequencing ***,the long-distance delivery of RNAs was proved to involve multiple ***,we analyzed the homology,motif,and tRNA-like structure(TLS)of long-distance mobile mRNAs identified by RNA-seq as well as the RNA-binding protein(RBP)in nine grafting combinations including Arabidopsis thaliana,Vitis vinifera,Cucumis sativus,Citrullus lanatus,Nicotiana benthamiana,Malus domestica,Pyrus spp.,Glycine max and Phaseolus *** several mRNAs were found to be shared in herbaceous,woody,and related species,the vast majority of long-distance mobile mRNAs were *** non-specific movement-related motifs were identified,while the TLS was not necessary for mRNA long distance *** addition,we found that RBPs were conserved among herbaceous and woody plants as well as related *** paper reports a further in-depth analysis of the endogenous mechanisms by which the species-specific transportable m RNAs were selected by bioinformatics,in order to provide insights for future research on long-distance mobile mRNAs.

关键词： Grafting combination Long-distance mobile mRNA TLS RNA binding proteins

Transition-Metal-Free Allylic Defluorination Cross-Electrophile Coupling Employing Rongalite

在线全文

学校读者我要写书评

暂无评论

Chinese Journal of Chemistry 2024年第12期42卷 1360-1366页

作者： Xiang-Long Chen Chun-Yan Wu Dong-Sheng Yang Bo-Cheng Tang Huai-Yu Wang Zhi-Cheng Yu Anling Li Yan-Dong Wu An-Xin Wu National Key Laboratory of Green Pesticide International Joint Research Center for Intelligent Biosensor Technology and HealthCollege of ChemistryCentral China Normal UniversityWuhanHubei 430079China state Key Laboratory of Chemical Biology and Drug Discovery Department of Applied Biology and Chemical Technology The HongKong Polytechnic UniversityKowloonHong Kong SARChina Department of Clinical Laboratory Center for Gene Diagnosisand Program of Clinical Laboratory MedicineZhongnan Hospital of Wuhan UniversityWuhanHubei 430062China

Comprehensive Summary The conversion of CF3-alkenes to gem-difluoroalkenes using reductive cross-coupling strategy has received much attention in recent years,however,the use of green and readily available reducing salt to mediate these reactions remains to be *** this work,a concise construction of gem-difluoroalkenes,which requires neither a catalyst nor a metal reducing agent,was ***,a safe and inexpensive industrial product,was employed as both a radical initiator and *** procedure was compatible with both linear and cyclic diaryliodonium salts,enabling a wide variety of substrates(>70 examples).The utility of this approach was demonstrated through gram-scale synthesis and efficient late-stage functionalizations of anti-inflammatory drugs.

关键词： Defluoroarylation Transition metal free gem-Difluoroalkenes Rongalite Single electron transfer C-C coupling Redox reactions Cross-coupling

Supramolecular complex glycoconjugate vaccine generates self-enhancement effects for carbohydrate antigen delivery

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 Chemical Letters 2024年第2期35卷 317-322页

作者： Han Lin Yanchun Li Kun Zhou Dan Li Hangyan Yu Jie Zhao Haofei Hong Zhifang Zhou Zhimeng Wu Key Laboratory of Carbohydrate Chemistry & Biotechnology Ministry of EducationSchool of BiotechnologyJiangnan UniversityWuxi 214122China

Targeting delivery of tumor-associated carbohydrate antigen(TACA)-based vaccine to antigen-presenting cells(APCs)mediated by endogenous antibodies can improve the immunogenicity of ***,an essential requirement of this approach is to generate high titers of endogenous antibodies in vivo through pre-immunization,which complicates the immunization procedure and may cause side ***,we report a new generation of APC-targeting TACA-based supramolecular complex vaccine,assembled by sialyl Thomsen-nouveau-bovine serum albumin-adamantine(sTn-BSA-Ada)and heptavalent rhamnose(Rha)-modifiedβ-cyclodextrin(β-CD)via host-guest *** complex vaccine retained anti-Rha antibodies recruiting capability and facilitated the APCs uptake of the vaccine via the interaction of the Fc-domain with the Fc receptors on *** demonstrate that direct immunization of complex vaccine elicited anti-Rha and anti-sTn specific immune response synchronously,generating a novel self-enhancement effect that can improve the antigen delivery to APCs in high *** structure-activity relationship(SAR)study proved that complex vaccine 4 with polyethylene glycol 6(PEG 6)linker in host molecule provoked a robust and specific sTn immune response comparable to the pre-immunization *** antisera induced by complex vaccine,either through direct immunization or pre-immunization,exhibited equal potency of cytotoxicity against the sTn expression cancer *** study provides a general platform for TACA-based vaccines with self-enhancement effects without the need for pre-immunization.

关键词： Glycoconjugate vaccine Endogenous antibody APC-targeting Supramolecular complex sTn antigen

Post-layout simulation driven analog circuit sizing

在线全文

学校读者我要写书评

暂无评论

Science China(Information Sciences) 2024年第4期67卷 289-300页

作者： Xiaohan GAO Haoyi ZHANG Siyuan YE Mingjie LIU David Z.PAN Linxiao SHEN Runsheng WANG Yibo LIN Ru HUANG School of Integrated Circuits Peking University School of Computer Science Peking University Department of Electrical and Computer Engineering University of Texas at Austin Institute of Electronic Design Automation Peking University

Post-layout simulation provides accurate guidance for analog circuit design, but post-layout performance is hard to be directly optimized at early design stages. Prior work on analog circuit sizing often utilizes pre-layout simulation results as the optimization objective. In this work, we propose a post-layoutsimulation-driven(post-simulation-driven for short) analog circuit sizing framework that directly optimizes the post-layout simulation performance. The framework integrates automated layout generation into the optimization loop of transistor sizing and leverages a coupled Bayesian optimization algorithm to search for the best post-simulation performance. Experimental results demonstrate that our framework can achieve over 20% better post-layout performance in competitive time than manual design and the method that only considers pre-layout optimization.

关键词： analog EDA transistor sizing Bayesian optimization post-layout simulation