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3D-structured carbon nanotube fibers as ultra-robust fabrics for adaptive electromagnetic shielding

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Nano Research 2024年第9期17卷 8521-8530页

作者： Dongping Li Ping wang Yuanyuan Li Zhenzhong yong Kunjie Wu Yan Zhang Jin wang Dongmei Hu Key Laboratory of Multifunctional and Smart Systems Suzhou Institute of Nano-Tech and Nano-BionicsChinese Academy of SciencesSuzhou 215123China College of Textile and Clothing Engineering of Soochow University Suzhou 215021China

Wireless communication technology is indispensable in our daily lives,but it also results in serious electromagnetic radiation ***,developing smart electromagnetic interference shielding materials with adjustable electromagnetic wave(EMW)responses holds significant promise for future electromagnetic shielding *** this study,we propose an electromagnetic shielding switch(ESS)characterized by tunable electromagnetic shielding performance achieved by fabricating a three-dimensional(3D)carbon nanotube-based spacer fabric(CNT-SF)and modifying CNT-SF with chemical vapor deposition(CCNT-SF).The CCNT-SF displays direction-dependent electrical conductivity by manipulating the warp and weft density,measuring 128 S/m transversely and 447 S/m *** characteristic allows the CCNT-SF to transmit or shield EMW by adjusting the angle of EMW incidence through fabric rotation,resulting in anisotropic electromagnetic shielding performance(33 dB transversely and 87 dB vertically).This feature enables switchable shielding with an on/off ratio of ***,the unique 3D structure confers excellent mechanical properties on the fabric,with compressive strength reaching 120 *** a flexible,lightweight,and mechanically robust ESS,the CCNT-SF holds promising prospects for mitigating the challenges of increasingly severe and intricate electromagnetic environments.

关键词： carbon nanotube spacer fabric electromagnetic shielding impact resistance joule heating electromagnetic shielding switch

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GSM系统频率同步的实现

电讯技术 2010年第6期50卷 37-40页

作者：王永学深圳职业技术学院电信学院广东深圳518055

在GSM系统中提出一种简单的频率同步算法,利用系统频率校正信道(FCCH)的信号特征估计接收信号的频率偏移,并通过频率补偿实现系统频率同步。仿真结果表明,该算法丢包率低,信噪比为8dB时就可完全检测到FCCH;频偏估计和补偿效果好,降低了... 详细信息

在GSM系统中提出一种简单的频率同步算法,利用系统频率校正信道(FCCH)的信号特征估计接收信号的频率偏移,并通过频率补偿实现系统频率同步。仿真结果表明,该算法丢包率低,信噪比为8dB时就可完全检测到FCCH;频偏估计和补偿效果好,降低了系统误码率。与传统的基于频域FCCH检测算法和最大似然匹配检测算法相比,所提算法基于时域信号处理,不需进行频域分析,其性能好且简单实用。

关键词： GSM 频率同步频率校正信道频偏估计

Surface water resource attenuation attribution and patterns in Hai River Basin

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Science China Earth Sciences 2024年第5期67卷 1545-1560页

作者： Qingming wang yong ZHAO Hao wang Jiaqi ZHAI Yue ZHANG Fan HE Rong LIU Mengyang MA State Key Laboratory of Simulation and Regulation of Water Cycle in River Basin China Institute of Water Resources and Hydropower Research(IWHR)Beijing 100038China Key Laboratory of Water Safety for Beijing-Tianjin-Hebei Region of Ministry of Water Resources Beijing 100038China General Institute of Water Resources and Hydropower Planning and Design Ministry of Water ResourcesBeijing 100120China

From 1956 to 2016,Hai River Basin suffered the most severe surface water resource attenuation among the 10 first-class river basins in *** on the surface water circulation process,and evolving characteristics of precipitation and underlying surface in Hai River Basin,this study attributed the causes of surface water resource attenuation to six primary impact factors,analyzed each factor's quantitative contribution,and revealed four patterns of surface water resource attenuation in Hai River *** pattern of the dominant factor:comparing the 1980–2000 period with the 1956–1979period,the variation of precipitation is the dominant factor of which contribution is 7 billion m^(3),accounting for 59%of total11.7 billion m^(3);comparing the 2001–2016 period with the 1956–1979 period,the increasing of vegetation cover in mountainous area is the dominant factor of which contribution is 2.78 billion m3,accounting for 51%of total 4.9 billion m^(3).The pattern of spatial distributions:comparing the 2001–2016 period with the 1956–1979 period,mountainous areas were more affected by increasing vegetation cover which for example contributed 42%in Luan River Basin mountainous;the plains were more impacted by farmland ridge interception which for example contributed 51%in Beisi River Basin *** pattern of attenuation trend:comparing the 2001–2016 period with the 1980–2000 period,surface water resources in mountainous areas continued to decline,owing to the increasing water consumption of large-scale vegetation restoration,while the influence of the underlying surface changes on surface water resources in plains areas tended to remain *** pattern of reversible change:among factors led to surface water resource attenuation,the human activity,including vegetation cover increase,farmland ridge interception,and urbanization expansion,contributed 36%of the attenuation,which resulted in the variation of precipitation-runoff *** study improved the traditiona

关键词： Hai River Basin Surface water resources Contribution decomposition Quantitative contribution Attenuation patterns

A Semi-Mechanistic Model for Predicting the Service Life of Composite Coatings on VW63Z Magnesium Alloy

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Acta Metallurgica Sinica(English Letters) 2024年第7期37卷 1161-1176页

作者： Xiaoxue wang Jingjing Guo Zihao Zeng Peng Zhou Rongqiao wang Xiuchun Liu Kai Gao Jingli Sun yong Yuan Fuhui wang School of Energy and Power Engineering Beihang UniversityBeijing100191China Beijing Institute of Space Long March Vehicle Beijing100076China The School of Materials Science and Engineering Northeastern UniversityShenyang110819China The State Key Laboratory of Rolling and Automation Northeastern UniversityShenyang110819China Shanghai Spaceflight Precision Machinery Institute Shanghai201600China

The application of Mg alloys is always accompanied by various coating technology, but a reliable model predicting the service life of coatings on Mg alloys is lacking but urgent. In this work, a semi-mechanistic model was proposed to predict the service life of plasma electrolytic oxidation (PEO) coating/electrophoretic coatings on a VW63Z Mg alloy;the model was decomposed into three parts: a first part depicting the degradation time of organic coating (L_(1)) and the diffusion time of electrolyte in the inorganic coating (L_(2)), respectively;a second part interpreting the breakdown of coatings due to the corrosion process (L_(3));a final part establishing an algorithm converting the accelerated tests into the real service environment (α);the effect of structural stress and dissimilar metal joints on the service life of coatings was also considered. Based on the ongoing accelerated experiments, the semi-mechanistic model could be able to predict the service life of both PEO coatings and composite coatings on VW63Z Mg alloy with a satisfiable precision.

关键词： Magnesium alloy Service life prediction Plasma electrolytic oxidation Electrophoretic coating Corrosion resistance

Ground state of Rydberg-dressed Bose gas confined in a toroidal trap

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Communications in Theoretical Physics 2024年第1期76卷 29-35页

作者： Lin-xue wang Hong-Li Yang Hui Liu Si-Lin Chen Ya-Jun wang Xiao-Fei Zhang Department of Physics School of Physics and Information ScienceShaanxi University of Science and TechnologyXi'an 710021China Department of Basic Sciences Air Force Engineering UniversityXi'an 710051China

The experimental realization of Rydberg dressing technology in ultracold atomic systems provides another superior platform for studying novel states of matter and macroscopic quantum *** this work,based on the mean-field theory,we have investigated the ground-state phases of a two-component Bose–Einstein condensate with Rydberg interaction and confined in a toroidal *** effects of the Rydberg interaction and external potential,especially the Rydberg blockade radius,on the ground-state structure of such a system have been investigated in full parameter *** results show that the Rydberg blockade radius,which can be regarded as another controllable parameter,can be used to obtain a variety of ground-state *** interestingly,it is found that for weak Rydberg interactions,the Rydberg blockade radius breaks the spontaneous rotational symmetry of the system,leading to the formation of a discrete unit cell *** strongly interacting cases,it can be used to realize different orders of discrete rotational symmetry breaking.

关键词： Bose-Einstein condensate Rydberg dressing toroidal trap

Strengthening strategy for high-performance friction stir lap welded joints based on 5083 Al alloy

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International Journal of Minerals, Metallurgy and Materials 2024年第11期31卷 2498-2507页

作者： Shen, Yujia wang, Jijie wang, Beibei xue, Peng Liu, Fengchao Ni, Dingrui Xiao, Bolv Ma, Zongyi College of Material Science and Engineering Shenyang Aerospace University Shenyang China Shi-changxu Innovation Center for Advanced Materials Institute of Metal Research Chinese Academy of Sciences Shenyang China Centre of Excellence for Advanced Materials Dongguan China CAS Key Laboratory of Nuclear Materials and Safety Assessment Institute of Metal Research Chinese Academy of Sciences Shenyang China Binzhou Institute of Technology Shandong Key Laboratory of Advanced Aluminium Materials and Technology Binzhou China

During aircraft, ship, and automobile manufacturing, lap structures are frequently produced among Al alloy skins, wall panels, and stiffeners. The occurrence of welding defects severely decreases mechanical properties during friction stir lap welding (FSLW). This study focuses on investigating the effects of rotation rate, multipass welding, and cooling methods on lap defect formation, microstructural evolution, and mechanical properties. Hook defects were eliminated by decreasing welding speed, applying two-pass FLSW with a small welding tool, and introducing additional water cooling, thus leading to a remarkable increase in effective sheet thickness and lap width. This above strategy yielded defect-free joints with an ultrafine-grained microstructure and increased tensile shear force from 298 to 551 N/mm. The fracture behavior of FSLW joints was systematically studied, and a fracture factor of lap joints was proposed to predict their fracture mode. By reducing the rotation rate, using two-pass welding, and employing additional water cooling strategies, an enlarged, strengthened, and defect-free lap zone with refined ultrafine grains was achieved with a quality comparable to that of lap welds based on 7xxx Al alloys. Importantly, this study provides a valuable FSLW method for eliminating hook defects and improving joint performance.

关键词： friction stir lap welding defect control microstructure fracture mechanisms mechanical properties

Characteristics of proppant transport and placement within rough hydraulic fractures

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Petroleum Exploration and Development 2024年第2期51卷 453-463页

作者： HUANG Hai ZHENG yong wang Yi wang Haizhu NI Jun wang Bin YANG Bing ZHANG Wentong School of Petroleum Engineering Xi’an Shiyou UniversityXi’an 710065China Shaanxi Key Laboratory of Carbon Dioxide Sequestration and Enhanced Oil Recovery Xi’an 710075China Shaanxi Provincial Key Laboratory of Oil and Gas Well and Reservoir Seepage and Rock Mechanics Xi’an 710065China Oil&Gas Field Production Construction Division PetroChina Tarim Oilfield CompanyKorla 841000China National Key Laboratory of Petroleum Resources and Engineering China University of Petroleum(Beijing)Beijing 102249China Shaanxi Yanchang Petroleum(Group)Co. Ltd.Xi’an 710075China

A three-dimensional reconstruction of rough fracture surfaces of hydraulically fractured rock outcrops is carried out by casting process,a large-scale experimental setup for visualizing rough fractures is built to perform proppant transport *** typical characteristics of proppant transport and placement in rough fractures and its intrinsic mechanisms are investigated,and the influences of fracture inclination,fracture width and fracturing fluid viscosity on proppant transport and placement in rough fractures are *** results show that the rough fractures cause variations in the shape of the flow channel and the fluid flow pattern,resulting in the bridging buildup during proppant transport to form unfilled zone,the emergence of multiple complex flow patterns such as channeling,reverse flow and bypassing of sand-carrying fluid,and the influence on the stability of the sand *** proppant has a higher placement rate in inclined rough fractures,with a maximum increase of 22.16 percentage points in the experiments compared to vertical fractures,but exhibits poor stability of the sand *** fracture width aggravates the bridging of proppant and induces higher pumping *** the viscosity of the fracturing fluid can weaken the proppant bridging phenomenon caused by the rough fractures.

关键词： reservoir fracturing rough fracture proppant transport and placement characteristics bridging buildup

Panoramic variation analysis of a family with neurodevelopmental disorders caused by biallelic loss-of-function variants in TMEM141,DDHD2,and LHFPL5

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Frontiers of Medicine 2024年第1期18卷 81-97页

作者： Liwei Sun xueting Yang Amjad Khan xue Yu Han Zhang Shirui Han Xiaerbati Habulieti Yang Sun Rongrong wang xue Zhang McKusick-Zhang Center for Genetic Medicine State Key Laboratory for Complex Severe and Rare DiseasesInstitute of Basic Medical Sciences Chinese Academy of Medical SciencesSchool of Basic Medicine Peking Union Medical CollegeBeijing100005China Chongqing Key Laboratory of Human Embryo Engineering Center for Reproductive MedicineNational Key Clinical Speciality Construction Project(Obstetrics and Gynecology)Chongqing Health Center for Women and ChildrenChongqing400013China Chongqing Clinical Research Center for Reproductive Medicine Women and Children’s Hospital of Chongqing Medical UniversityChongqing400013China Faculty of Biological Sciences Department of ZoologyUniversity of Lakki MarwatKhyber Pakhtunkhwa28420Pakistan Institute for Medical Genetics and Applied Genomics University of TübingenTübingen72076Germany Alexander von Humboldt fellowship Foundation Berlin10117Germany Department of Pediatrics The First Affiliated Hospital of Guangxi Medical UniversityNanning530000China Department of Laboratory Medicine State Key Laboratory for Complex Severe and Rare DiseasesPeking Union Medical College HospitalChinese Academy of Medical Science and Peking Union Medical CollegeBeijing100730China

Highly clinical and genetic heterogeneity of neurodevelopmental disorders presents a major challenge in clinical genetics and *** variation analysis is imperative to analyze the disease phenotypes resulting from multilocus genomic ***,a Pakistani family with parental consanguinity was presented,characterized with severe intellectual disability(ID),spastic paraplegia,and *** mapping,integrated single nucleotide polymorphism(SNP)array,whole-exome sequencing,and whole-genome sequencing were performed,and homozygous variants in TMEM141(c.270G>A,***90^(*)),DDHD2(c.411+767_c.1249-327del),and LHFPL5(c.250delC,***84^(*))were identified.A Tmem141^(***90^(*)/***90^(*))mouse model was *** studies showed impairments in learning ability and motor *** slice electrophysiology and Golgi staining demonstrated deficient synaptic plasticity in hippocampal neurons and abnormal dendritic branching in cerebellar Purkinje *** electron microscopy showed abnormal mitochondrial ***,studies on a human in vitro neuronal model(SH-SY5Y cells)with stable shRNA-mediated knockdown of TMEM141 showed deleterious effect on bioenergetic function,possibly explaining the pathogenesis of replicated phenotypes in the cross-species mouse ***,panoramic variation analysis revealed that multilocus genomic variations of TMEM141,DDHD2,and LHFPL5 together caused variable phenotypes in ***,the biallelic loss-of-function variants of TMEM141 were responsible for syndromic ID.

关键词： neurodevelopmental disorder autosomal recessive intellectual disability consanguinity spastic paraplegia hearing loss TMEM141

Using MsfNet to Predict the ISUP Grade of Renal Clear Cell Carcinoma in Digital Pathology Images

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Computers, Materials & Continua 2024年第1期78卷 393-410页

作者： Kun Yang Shilong Chang Yucheng wang Minghui wang Jiahui Yang Shuang Liu Kun Liu Linyan xue College of Quality and Technical Supervision Hebei UniversityBaoding071002China National and Local Joint Engineering Research Center of Metrology Instrument and System Hebei UniversityBaoding071002China Hebei Technology Innovation Center for Lightweight of New Energy Vehicle Power System Hebei UniversityBaoding071002China

Clear cell renal cell carcinoma(ccRCC)represents the most frequent form of renal cell carcinoma(RCC),and accurate International Society of Urological Pathology(ISUP)grading is crucial for prognosis and treatment *** study presents a new deep network called Multi-scale Fusion Network(MsfNet),which aims to enhance the automatic ISUP grade of ccRCC with digital histopathology pathology *** MsfNet overcomes the limitations of traditional ResNet50 by multi-scale information fusion and dynamic allocation of channel *** model was trained and tested using 90 Hematoxylin and Eosin(H&E)stained whole slide images(WSIs),which were all cropped into 320×320-pixel patches at 40×*** achieved a micro-averaged area under the curve(AUC)of 0.9807,a macro-averaged AUC of 0.9778 on the test *** Gradient-weighted Class Activation Mapping(Grad-CAM)visually demonstrated MsfNet’s ability to distinguish and highlight abnormal areas more effectively than *** t-Distributed Stochastic Neighbor Embedding(t-SNE)plot indicates our model can efficiently extract critical features from images,reducing the impact of noise and redundant *** results suggest that MsfNet offers an accurate ISUP grade of ccRCC in digital images,emphasizing the potential of AI-assisted histopathological systems in clinical practice.

关键词： Renal cell carcinoma computer-aided diagnosis pathology image deep learning machine learning