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| 1 | Arrangement of High-standard Basic Farmland Construction Based on Village-region Cultivated Land Quality Uniformity显示文摘As an important constitute of land consolidation, high-standard basic farmland construction is an important means to protect the quantity, quality and ecological environment of cultivated land. Its target not only lies in the increase of cultivated land quantity, but also the improvement of cultivated land quality, agricultural production conditions and ecosystem environments. In the present study, the quality evaluation method and construction arrangement of cultivated land were explored to facilitate the process of decision-making and implementation for high-standard basic farmland construction(HSBFC) with administrative village as the unit. Taking the land comprehensive improvement project area in Quzhou County, Handan City, Hebei Province as a case study, the whole process of the study comprised of three steps: 1) establishment of the evaluation model of cultivated land quality uniformity based on regional optimum cultivated land quality, and construction of the uniformity evaluation index system from the aspects of soil fertility quality, engineering quality, spatial quality and eco-environment quality, according to the new concept of cultivated land quality; 2) calculation of cultivated land quality uniformity by grading indicators, assigning scores and weighting sums, exploring the local homogenization characteristics of regional cultivated land quality through spatial autocorrelation analysis, and analyzing the constraints and transformative potential of barrier factors; 3) arrangement of HSBFC according to the principle of concentration, continuity and priority to the easy operation. The results revealed that the value of farmland quality uniformity for the administrative villages in the study area was between 7.76 and 21.96, and there was a difference between various administrative villages. The regional spatial autocorrelation patterns included High-High(HH), Low-Low(LL), High-Low(HL) and Low-High(LH). These indicate that regional cultivated land quality has local homogenization characteristics. The most restrictive factors in the study area were the medium and low transformation difficulty indexes, including soil organic matter content, farmland shelterbelt network density, field regularity and scale of the field. In addition, there were also high transformation difficulty indicators in some areas, such as sectional configuration. The project area was divided into four partitions: major construction area, secondary construction area, general construction area, and conditional construction area. The cultivated land area of each subarea was 1538.85 ha, 1224.27 ha, 555.93 ha, and 1666.63 ha, respectively. This comprised of 30.87%, 24.56%, 11.15% and 33.42% of the total project area, respectively. The evaluation model and index system could satisfy the evaluation of farmland quality and diagnosis of obstacle factors to facilitate the subsequent construction decision. The present study provides reference for the practice of regional HSBFC, and a new feasible idea and method for related studies. | SONG Wen WU Kening ZHAO Huafu ZHAO Rui LI Ting | 2019 | Chinese Geographical Science2019，29，2： | 12 |
| 2 | Thermal-Hydraulic-Structural Analysis and Design Optimization for Micron-Sized Printed Circuit Heat Exchanger显示文摘The Printed Circuit Heat Exchanger(PCHE) is one of the most promising heat exchangers for Synergetic Air-breathing and Rocket Engine(SABRE). To reduce pressure drop and improve compactness, the micron-sized PCHE made up of rectangular channels of tens of microns in size, is used in SABRE. In present work, we focus on thermal-hydraulic-structural characteristics of micron-sized PCHE by conducting three-dimensional(3-D) numerical simulation. Helium and hydrogen are employed as the working fluids and the Stainless Steel 316(SS316) as the solid substrate. The thermal-hydraulic performance of the micron-sized PCHE is discussed by using the commercial Computational Fluid Dynamics(CFD) software of Fluent. ANSYSMechanical is also employed to simulate stress field of representative PCHE channels. The mechanical stress induced by pressure loading and the thermal stress induced by temperature gradient are found to be equally important sources of stress. To improve comprehensive performances of micron-sized PCHE, two types of channel arrangements and different channel aspect ratios are studied. The double banking is of higher thermal-hydraulic performance compared to the single banking while the stress performance is identical for the two modes. Meanwhile, the effect of channel aspect ratio is investigated by comparing thermal-hydraulic characteristics and structural stress of the model. The rectangular channel with w/h=2 achieves the most balanced stress characteristic and higher thermal-hydraulic performance. | HOU Yaqiong TANG Guihua | 2019 | Journal of Thermal Science2019，28，2： | 11 |
| 3 | Stepwise-Nanocavity-Assisted Transmissive Color Filter Array Microprints显示文摘Visible-light color flters using patterned nanostructures have attracted much interest due to their various advantages such as compactness,enhanced stability,and environmental friendliness compared with traditional pigment or dye-based optical flters.While most existing studies are based on planar nanostructures with lateral variation in size,shape,and arrangement,the vertical dimension of structures is a long-ignored degree of freedom for the structural colors.Herein,we demonstrate a synthetic platform for transmissive color flter array by coordinated manipulations between height-varying nanocavities and their lateral flling fractions.Te thickness variation of those nanocavities has been fully deployed as an alternative degree of freedom,yielding vivid colors with wide gamut and excellent saturation.Experimental results show that the color-rendering capability of the pixelated nanocavities can be still retained as pixels are miniaturized to 500 nm.Crosstalk between closely spaced pixels of a Bayer color flter arrangement was calculated,showing minimal crosstalk for 1μm2 square subpixels.Our work provides an approach to designing and fabricating ultracompact color flter arrays for various potential applications including stained-glass microprints,microspectrometers,and high-resolution image sensing systems. | Yasi Wang Mengjie Zheng Qifeng Ruan Yanming Zhou Yiqin Chen Peng Dai Zhengmei Yang Zihao Lin Yuxiang Long Ying Li Na Liu Cheng-Wei Qiu Joel K.W.Yang Huigao Duan | 2018 | Research2018，，1： | 8 |
| 4 | 关于世界男子400m速度和速度布局的研究──兼析我国男子400m成绩滞后因素显示文摘 | | 1999 | 浙江体育科学1999，21，4： | 7 |
| 5 | Electron microscopy observations of surface morphologies and particle arrangement behaviors of magnetic fluids显示文摘The surface morphology of quasi-periodic stripe-shaped patterns of magnetite fluids was observed in applied perpendicular magnetic fields by means of scanning electron microscopy. The nanoparticles of the magnetite fluids are arranged in oriental quasilinear chains in applied perpendicular magnetic fields as observed using transmission electron microscopy. This arrangement results from particle-particle interactions and particle-carrier liquids interactions, which are eventually controlled by the magnetic fields distribution. | 沈辉 徐雪青 王伟 | 2003 | Science China(Technological Sciences)2003，46，2： | 6 |
| 6 | Hierarchy in materials for maximized efficiency显示文摘HIERARCHY Hierarchy,originated from an ancient Greek word ‘εραρχα’is a property characterized by the arrangement of a set of individual items[l]that are placed‘above’,‘below’or‘at the same level as’one another in different systems.These items can be physical matter such as atoms,molecules,particles;objects,etc.,or can be abstract and intangible entities such as names,values,categories,etc.Hierarchy,although we are not consciously aware of its existence;is an essential concept in a wide variety of fields;such as life science,materials science;computer science,philosophy,mathematics,physics,chemistry,biology,geography,topography,organizational theory,systems theory,architecture,urban construction,industrial processes and the social sciences. | Li-Hua Chen Yu Li Bao-Lian Su | 2020 | National Science Review2020，7，11： | 4 |
| 7 | Ultrathin Acoustic Parity-Time Symmetric Metasurface Cloak显示文摘Invisibility or unhearability cloaks have been made possible by using metamaterials enabling light or sound to fow around obstacle without the trace of refections or shadows.Metamaterials are known for being fexible building units that can mimic a host of unusual and extreme material responses,which are essential when engineering artifcial material properties to realize a coordinate transforming cloak.Bending and stretching the coordinate grid in space require stringent material parameters;therefore,small inaccuracies and inevitable material losses become sources for unwanted scattering that are decremental to the desired efect.Tese obstacles further limit the possibility of achieving a robust concealment of sizeable objects from either radar or sonar detection.By using an elaborate arrangement of gain and lossy acoustic media respecting parity-time symmetry,we built a one-way unhearability cloak able to hide objects seven times larger than the acoustic wavelength.Generally speaking,our approach has no limits in terms of working frequency,shape,or size,specifcally though we demonstrate how,in principle,an object of the size of a human can be hidden from audible sound. | Hao-xiang Li Mar-a Rosendo-López Yi-fan Zhu Xu-dong Fan Daniel Torrent Bin Liang Jian-chun Cheng Johan Christensen | 2019 | Research2019，，1： | 4 |
| 8 | New Scheme of Roadway Layout in Longwall Top-Coal Caving System显示文摘Based on mining design theory and practice, a production system of stagger-arrangement roadway in thick seams is put forward for the first time. The system can comprehensively solve the problems in longwall top-coal caving system, such as raising recovery ratio, discharging gas, preventing spontaneous combustion and improving the upkeep of roadway etc. | 赵景礼 富强 | 1998 | International Journal of Mining Science and Technology1998，19，2： | 3 |
| 9 | Diffusion and sound absorption properties of the quadratic residue diffuser structure with perforated panel显示文摘Acoustic structure study always is the academic research interest. Diffusion ab?sorbing structure(DiflFsorber) has good research value because it has both diflFusion property and sound absorption property. Quadratic residue diffusers(QRD) structure which had good diffusion property was combined with the perforated panel which had good sound absorption property in this study. According to standard AES-4id-2001, the diffusion experiments were carried out to study QRD structure and ones composited with perforated-panels which had1 mm-thickness and perforated percentage of 3%, 5%, 8% respectively. The polar coordinate diagrams of different structure were analyzed to derive the diffusion coefficients. Results showed that the composite structure still had good diffusion performance in the frequency range from100 Hz to 800 Hz. The reflection sound energy of composite structure reduced obviously in the perforated panel resonance frequency range where there was about 2 dB reduction averagely.The study result can provide the reference for the design and development of diifsorber. | CAI Jun BAO Fei WANG Yachen WANG Yanqin | 2016 | Chinese Journal of Acoustics2016，35，3： | 3 |
| 10 | Electrochemical Study on FXL-I4 Collecting Wolframite without Pb^(2+) Flotation显示文摘In this paper,FXL-14 (tetradecyl iminobimetyl phosphonic acid) as a collector for floating wolframite without Pb2+ and itsadsorption mechanism were studied by electrochemical method.Flotation experiment results showed that in the wide range of pHvalue activation of FXL-14 collecting wolframite with Pb2+ was not needed.Wolframite—carbon paste electrode andsmall-amplitude triangular potential sweep were used to measure the electro-double-layer capacitance of wolframite in theFXL-14 solution (with and without of the presence of 1×10-4MPb2+).It is showed that in spite of concentration of Pb2+ in theflotation processing,with FXL-14 (800mg/l) the electro-double-layer capacitance was bigger than with FXL-14 (800mg/l)and Pb2+. | Zhu Yimin Xiao Youming Hunan Non-ferrous Metal Research Institute | 1989 | Rare Metals1989，9，4： | 3 |
| 11 | Accelerated design and characterization of non-uniform cellular materials via a machine-learning based framework显示文摘Cellular materials,widely found in engineered and nature systems,are highly dependent on their geometric arrangement.A nonuniform arrangement could lead to a significant variation of mechanical properties while bringing challenges in material design.Here,this proof-of-concept study demonstrates a machine-learning based framework with the capability of accelerated characterization and pattern generation.Results showed that the proposed framework is capable of predicting the mechanical response curve of any given geometric pattern within the design domain under appropriate neural network architecture and parameters.Additionally,the framework is capable of generating matching geometric patterns for a targeted response through a databank constructed from our machine learning model.The accuracy of the predictions was verified with finite element simulations and the sources of errors were identified.Overall,our machine-learning based framework can boost the design efficiency of cellular materials at unit level,and open new avenues for the programmability of function at system level. | Chunping Ma Zhiwei Zhang Benjamin Luce Simon Pusateri Binglin Xie Mohammad H.Rafiei Nan Hu | 2020 | npj Computational Materials2020，，1： | 3 |
| 12 | 为有效再论体院田径课程的构建原则与方法显示文摘田径课业是体育专业学生的主修课程之一,其课程的组织不仅受到专业培养方向与整个教学计划的控制与制约,同时也与其课程的内部结构和教学特点密切相关,对此我们曾在“系统观与教学过程最优化——构建体院田径课程教学模式的原则与方法”(见西安体院学报92年4期)一文中进行过讨论。在该文中我们根据体院田径教学的特点与课程的内部结构。 | 张启明 张武维 许崇高 | 1993 | 西安体育学院学报1993，10，4： | 3 |
| 13 | Reducibility of hyperplane arrangements显示文摘Certain problems on reducibility of central hyperplane arrangements are settled. Firstly, a necessary and sufficient condition on reducibility is obtained. More precisely, it is proved that the number of irreducible components of a central hyperplane arrangement equals the dimension of the space consisting of the logarithmic derivations of the arrangement with degree zero or one. Secondly, it is proved that the decomposition of an arrangement into a direct sum of its irreducible components is unique up to an isomorphism of the ambient space. Thirdly, an effective algorithm for determining the number of irreducible components and decomposing an arrangement into a direct sum of its irreducible components is offered. This algorithm can decide whether an arrangement is reducible, and if it is the case, what the defining equations of irreducible components are. | Guang-feng JIANG & Jian-ming YU Department of Mathematics, Beijing University of Chemical Technology, Beijing 100029, China Academy of Mathematics and Systems Science, Chinese Academy of Sciences, Beijing 100080, China | 2007 | Science China Mathematics2007，50，5： | 3 |
| 14 | Fiber Optic Moiré Interferometer显示文摘A novel fiber optic moiréinterferometer has been developed and demonstrated.A He-Ne laser and three high birefringence fibers were used to configurate a fiber optic interferometer.The moiréfringe patterns formed by the interferometer depend on the arrangement of three fiber ends.The experiment results and the intensity distribution function of the interference patterns are given. | 苑立波 | 1997 | Chinese Physics Letters1997，14，9： | 3 |
| 15 | Mesoporous bioactive glass composition effects on degradation and bioactivity显示文摘Mesoporous bioactive glasses(MBGs)are promising materials for regenerative medicine,due to their favorable properties including bioactivity and degradability.These key properties,but also their surface area,pore structure and pore volume are strongly dependent on synthesis parameters and glass stoichiometry.However,to date no systematic study on MBG properties covering a broad range of possible compositions exists.Here,24 MBG compositions in the SiO_(2)-CaO-P_(2)O_(5) system were synthesized by varying SiO_(2)(60-90 mol%),CaO and P_(2)O_(5) content(both 0 to 40 mol-%),while other synthesis parameters were kept constant.Mesopore characteristics,degradability and bioactivity were analysed.The results showed that,within the tested range of compositions,mesopore formation required a molar SiO_(2) content above 60%but was independent of CaO and P_(2)O_(5) content.While mesopore size did not depend on glass stoichiometry,mesopore arrangement was influenced by the SiO_(2) content.Specific surface area and pore volume were slightly altered by the SiO_(2) content.All materials were degradable;however,degradation as well as bioactivity,i.e.the ability to form a CaP mineral on the surface,depended on stoichiometry.Major differences were found in early surface reactions in simulated body fluid:where some MBGs induced direct hydroxyapatite crystallization,high release of calcium in others resulted in calcite formation.In summary,degradation and bioactivity,both key parameters of MBGs,can be controlled by glass stoichiometry over a broad range while leaving the unique structural parameters of MBGs relatively unaffected.This allows targeted selection of material compositions for specific regenerative medicine applications. | M.Schumacher P.Habibovic S.van Rijt | 2021 | Bioactive Materials2021，6，7： | 2 |
| 16 | Loop Closure Detection With Reweighting Net VLAD and Local Motion and Structure Consensus显示文摘Dear Editor,Loop closure detection(LCD)is an important module in simultaneous localization and mapping(SLAM).In this letter,we address the LCD task from the semantic aspect to the geometric one.To this end,a network termed as AttentionNetVLAD which can simultaneously extract global and local features is proposed.It leverages attentive selection for local features,coupling with reweighting the soft assignment in NetVLAD via the attention map for global features.Given a query image,candidate frames are first identified coarsely by retrieving similar global features in the database via hierarchical navigable small world(HNSW).As global features mainly summarize the semantic information of images and lead to compact representation,information about spatial arrangement of visual elements is lost. | Kaining Zhang Jiayi Ma Junjun Jiang | 2022 | IEEE/CAA Journal of Automatica Sinica2022，9，6： | 2 |
| 17 | Effect of Operating Condition and Structural Parameter in the Hydrostatic Thrust CO_2 Bearing显示文摘Hydrostatic thrust bearings are widely applied in rotating machinery field. Its comprehensive performance and safe operation is of great significance for ensuring equipment efficiency. In this paper, the numerical method is adopted to investigate the slit-restricted hydrostatic thrust CO_2 bearing with a small film thickness. The research is carried out from two aspects, which mainly consider the operating conditions and structural parameters. Firstly, the influence of different working fluid types including real air and CO_2(include subcritical and supercritical state) on the static characteristics of bearing is studied, and the results indicate that the bearing with CO_2 as working fluid has a better static performance. Secondly, the influence of rotor rotating speed is studied and the conclusion shows that the rotating speed has a significant effect on bearing static characteristics. Thirdly, the influence of different slit arrangement forms is investigated, and the consequence indicates that the circumferential slits show a better load capacity than that of radial slits, while the flow rate difference is small. Finally, the effect of film thickness on bearing static performance is investigated and the research shows that this factor affects static performance in a dramatical way. When the clearance tends to be smaller, the load capacity increases sharply, while the massflow rate of working fluid decreases. | LI Liangliang XIE Yonghui | 2019 | Journal of Thermal Science2019，28，3： | 2 |
| 18 | Sciatic nerve injury alters the spatial arrangement of neurons and glial cells in the anterior horn of the spinal cord显示文摘The spatial arrangement of the cell is important and considered as underlying mechanism for mathematical modeling of cell to cell interaction.The ability of cells to take on the characteristics of other cells in an organism,it is important to understand the dynamical behavior of the cells.This method implements experimental parameters of the cell-cell interaction into the mathematical simulation of cell arrangement.The purpose of this research was to explore the three-dimensional spatial distribution of anterior horn cells in the rat spinal cord to examine differences after sciatic nerve injury.Sixteen Sprague-Dawley male rats were assigned to control and axotomy groups.Twelve weeks after surgery,the anterior horn was removed for first-and second-order stereological studies.Second-order stereological techniques were applied to estimate the pair correlation and cross-correlation functions using a dipole probe superimposed onto the spinal cord sections.The findings revealed 7% and 36% reductions in the mean volume and total number of motoneurons,respectively,and a25% increase in the neuroglial cell number in the axotomized rats compared to the control rats.In contrast,the anterior horn volume remained unchanged.The results also indicated a broader gap in the pair correlation curve for the motoneurons and neuroglial cells in the axotomized rats compared to the control rats.This finding shows a negative correlation for the distribution of motoneurons and neuroglial cells in the axotomized rats.The cross-correlation curve shows a negative correlation between the motoneurons and neuroglial cells in the axotomized rats.These findings suggest that cellular structural and functional changes after sciatic nerve injury lead to the alterations in the spatial arrangement of motoneurons and neuroglial cells,finally affecting the normal function of the central nervous system.The experimental protocol was reviewed and approved by the Animal Ethics Committee of Shahid Beheshti University of Medical Sciences(approval No.IR.SBMU.MSP.REC1395.375) on October 17,2016. | Ali Rashidiani-Rashidabadi Mohammad Hassan Heidari Ensieh Sajadi Fatemeh Hejazi Fatemeh Fadaei Fathabady Yousef Sadeghi Abbas Aliaghaei Amir Raoofi Mohammad-Amin Abdollahifar Reza Mastery Farahni | 2019 | Neural Regeneration Research2019，14，10： | 2 |
| 19 | Recent Advances in Two-Dimensional Magnets:Physics and Devices towards Spintronic Applications显示文摘The emergence of low-dimensional nanomaterials has brought revolutionized development of magnetism,as the size effect can significantly influence the spin arrangement.Since the first demonstration of truly two-dimensional magnetic materials(2DMMs)in 2017,a wide variety of magnetic phases and associated properties have been exhibited in these 2DMMs,which offer a new opportunity to manipulate the spin-based devices efficiently in the future.Herein,we focus on the recent progress of 2DMMs and heterostructures in the aspects of their structural characteristics,physical properties,and spintronic applications.Firstly,the microscopy characterization of the spatial arrangement of spins in 2D lattices is reviewed.Afterwards,the optical probes in the light-matter-spin interactions at the 2D scale are discussed.Then,particularly,we systematically summarize the recent work on the electronic and spintronic devices of 2DMMs.In the section of electronic properties,we raise several exciting phenomena in 2DMMs,i.e.,long-distance magnon transport,field-effect transistors,varying magnetoresistance behavior,and(quantum)anomalous Hall effect.In the section of spintronic applications,we highlight spintronic devices based on 2DMMs,e.g.,spin valves,spin-orbit torque,spin field-effect transistors,spin tunneling field-effect transistors,and spin-filter magnetic tunnel junctions.At last,we also provide our perspectives on the current challenges and future expectations in this field,which may be a helpful guide for theorists and experimentalists who are exploring the optical,electronic,and spintronic properties of 2DMMs. | Vertikasari PNingrum Bowen Liu Wei Wang Yao Yin Yi Cao Chenyang Zha Hongguang Xie Xiaohong Jiang Yan Sun Sichen Qin Xiaolong Chen Tianshi Qin Chao Zhu Lin Wang Wei Huang | 2020 | Research2020，，1： | 2 |
| 20 | Regular arrangement of collecting venules:Does patient age affect its accuracy?显示文摘AIM:To address the diagnostic value of the regular arrangement of collecting venules(RAC)among old age patients. METHODS:A total of 390 consecutive patients whose Helicobacter pylori(H.pylori)status was known and who received upper gastrointestinal endoscopy,were retrospectively studied for the presence or absence of RAC as well as gastric mucosal atrophy.The sensitivity, specificity,positive predictive value,negative predic-tive value and accuracy of RAC to detect normal gastric mucosa were assessed and were compared among two different age groups of patients. RESULTS:The mean age±standard deviation(SD)of included patients(n=390),was 62.9±13 years.The sensitivity,specificity,positive predictive value,negative predictive value and accuracy of RAC to detect normal gastric mucosa were 91.7%,66.1%,18.8%,99%and 68.1%respectively.Although the sensitivity,specificity,positive predictive value,negative predictive value and accuracy of RAC among patients<60 years(n= 139)was 94.7%,71.2%,46.2%,98.1%and 76.1%,respectively,it was 80%,64.3%,5.1%,93%and 64.6%, respectively,among patients≥60 years(n=251). Younger Patients(<60 years),have highly significant rates of RAC sensitivity,positive predictive value,and accuracy(P≤0.001,≤0.001 and≤0.02,respectively).Older patients had highly significant rates of H. pylori infection and gastric mucosal atrophy(P≤0.01). CONCLUSION:Although RAC is a valuable sign for real-time identification of normal gastric mucosa,its accuracy seems to be affected by the patient's age. | Alshimaa Alaboudy Ashraf Elbahrawy Shigemi Matsumoto Ghada M Galal Tsutomu Chiba | 2011 | World Journal of Gastrointestinal Endoscopy2011，3，6： | 2 |
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