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Spatial variability of soil total nitrogen,phosphorus and potassium in Renshou County of Sichuan Basin,China

Journal of Integrative Agriculture 2019年第2期18卷 279-289页

作者： GAO Xue-song XIAO Yi DENG Liang-ji LI Qi-quan WANG Chang-quan LI Bing DENG Ou-ping zeng min College of Resources Sichuan Agricultural UniversityChengdu 611130P.R.China

Understanding soil nutrient distributions and the factors affecting them are crucial for fertilizer management and environmental protection in vulnerable ecological *** on 555 soil samples collected in 2012 in Renshou County,located in the purple soil hilly area of Sichuan Basin,China,the spatial variability of soil total nitrogen(TN),total phosphorus(TP)and total potassium(TK)was studied with geostatistical analysis and the relative roles of the affecting factors were quantified using regression *** means of TN,TP and TK contents were 1.12,0.82 and 9.64 g kg^(–1),*** coefficients of variation ranged from 30.56 to 38.75%and the nugget/sill ratios ranged from 0.45 to 0.61,indicating that the three soil nutrients had moderate variability and spatial *** distribution patterns were *** and TK were associated with patterns of obvious spatial distribution trends while the spatial distribution of TN was characterized by higher *** group,land use type and topographic factors explained 26.5,35.6 and 8.4%of TN variability,respectively,with land use being the dominant *** material,soil group,land use type and topographic factors explained 17.5,10.7,12.0 and 5.0%of TP variability,respectively,and both parent material and land use type played important *** parent material and soil type contributed to TK variability and could explain 25.1 and 13.7%of TK variability,*** attention should focus on adopting reasonable land use types for the purposes of fertilizer management and consider the different roles of the affecting factors at the landscape scale in this purple soil hilly area.

关键词： soil nutrient spatial variability affecting factors purple soil hilly area of China

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F2上第三类向量深度的分布及序列{(E-1)^m(s)}m≥0的周期

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通信学报 2008年第4期29卷 51-56页

作者：曾敏骆源上海交通大学计算机科学与工程系

向量复杂程度的一个研究角度是向量的深度。将Etzion和Roth提出的向量深度归纳为3类向量深度,通过有限长序列的周期与第三类向量深度之间的关系,给出了F2上任意n维向量空间的第三类向量深度的分布,并且利用向量算子的矩阵描述,从序列{(E... 详细信息

向量复杂程度的一个研究角度是向量的深度。将Etzion和Roth提出的向量深度归纳为3类向量深度,通过有限长序列的周期与第三类向量深度之间的关系,给出了F2上任意n维向量空间的第三类向量深度的分布,并且利用向量算子的矩阵描述,从序列{(E-1)m(s)}m≥0终归周期的角度,进一步考察了第三类向量深度为∞的向量的性质。

关键词：向量深度分布向量算子及级数终归周期序列线性复杂度

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RESEARCH & DESIGN OF 60 kW SOFT-SWITCHING PLASMA CONVERTER

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Chinese Journal of Mechanical Engineering 2006年第1期19卷 28-31页

作者： DU Gulping HUANG Shisheng WANG Zhenmin zeng min CHEN Lijun Research and Design Center Guangzhou Electric Apparatus Research Institute Guangzhou 510300 China College of Mechanical Engineering South China University of Technology Guangzhou 510640 China College of Electrical and Power South China University of Technology Guangzhou 510640 China

A novel 60 kW plasma converter with full range soft-switch by utilizing magnetizing inductance, leakage inductance and distributed inductance is introduced. The current injection phase-shifting technique is introduced into the research of soft-switching plasma converter successfully. The magnetic bias of transformer and the protection of switching parts are solved. The tests state that the power supply has excellent characteristics and higher efficiency and can meet the demand of large power plasma process well.

关键词： Soft-switching Current injection technique Plasma converter

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SVM-based Identification and Un-calibrated Visual Servoing for Micro-manipulation

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International Journal of Automation and computing 2010年第1期7卷 47-54页

作者： Xin-Han Huang Xiang-Jin zeng min Wang Department of Control Science and Engineering, Huazhong University of Science and Technology, Wuhan 430074, PRC Department of Control Science and Engineering Huazhong University of Science and Technology Wuhan PRC

This paper presents an improved support vector machine （SVM） algorithm, which employs invariant moments-based edge extraction to obtain feature attribute. A heuristic attribute reduction algorithm based on rough set＇s discernible matrix is proposed to identify and classify micro-targets. To avoid the complicated calibration for intrinsic parameters of camera, an improved Broyden＇s method is proposed to estimate the image Jacobian matrix which employs Chebyshev polynomial to construct a cost function to approximate the optimization value. Finally, a visual controller is designed for a robotic micromanipulation system. The experiment results of micro-parts assembly show that the proposed methods and algorithms are effective and feasible.

关键词： Micro-assembly support vector machine part identification Broyden method visual servoing

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Highly Sensitive Ammonia Gas Sensors at Room Temperature Based on the Catalytic Mechanism of N,C Coordinated Ni Single-Atom Active Center

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Nano-Micro Letters 2024年第12期16卷 515-531页

作者： Wenjing Quan Jia Shi min zeng Wen Lv Xiyu Chen Chao Fan Yongwei Zhang Zhou Liu Xiaolu Huang Jianhua Yang Nantao Hu Tao Wang Zhi Yang National Key Laboratory of Advanced Micro and Nano Manufacture Technology Shanghai Jiao Tong UniversityShanghai 200240People’s Republic of China Department of Micro/Nano Electronics School of Electronic Information and Electrical EngineeringShanghai Jiao Tong UniversityShanghai 200240People’s Republic of China Shanghai Key Laboratory of Intelligent Sensing and Detection Technology School of Mechanical and Power EngineeringEast China University of Science and TechnologyShanghai 200237People’s Republic of China

Significant challenges are posed by the limitations of gas sensing mechanisms for trace-level detection of ammonia(NH3).In this study,we propose to exploit single-atom catalytic activation and targeted adsorption properties to achieve highly sensitive and selective NH3 gas ***,Ni singleatom active sites based on N,C coordination(Ni-N-C)were interfacially confined on the surface of two-dimensional(2D)MXene nanosheets(Ni-N-C/Ti_(3)C_(2)Tx),and a fully flexible gas sensor(MNPE-Ni-N-C/Ti_(3)C_(2)Tx)was *** sensor demonstrates a remarkable response value to 5 ppm NH3(27.3%),excellent selectivity for NH3,and a low theoretical detection limit of 12.1 *** analysis by density functional calculation reveals that the Ni single-atom center with N,C coordination exhibits specific targeted adsorption properties for ***,its catalytic activation effect effectively reduces the Gibbs free energy of the sensing elemental reaction,while its electronic structure promotes the spill-over effect of reactive oxygen species at the gas-solid *** sensor has a dual-channel sensing mechanism of both chemical and electronic sensitization,which facilitates efficient electron transfer to the 2D MXene conductive network,resulting in the formation of the NH3 gas molecule sensing ***,the passivation of MXene edge defects by a conjugated hydrogen bond network enhances the long-term stability of MXene-based electrodes under high humidity *** work achieves highly sensitive room-temperature NH3 gas detection based on the catalytic mechanism of Ni single-atom active center with N,C coordination,which provides a novel gas sensing mechanism for room-temperature trace gas detection research.

关键词： Gas sensor Single atom Catalytic activation Targeted adsorption End-sealing passivation

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Outstanding Humidity Chemiresistors Based on Imine-Linked Covalent Organic Framework Films for Human Respiration Monitoring

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Nano-Micro Letters 2023年第9期15卷 368-383页

作者： Xiyu Chen Lingwei Kong Jaafar Abdul-Aziz Mehrez Chao Fan Wenjing Quan Yongwei Zhang min zeng Jianhua Yang Nantao Hu Yanjie Su Hao Wei Zhi Yang Key Laboratory of Thin Film and Microfabrication(ministry of Education) Department of Micro/Nano ElectronicsSchool of Electronic Information and Electrical EngineeringShanghai Jiao Tong UniversityShanghai 200240People’s Republic of China

Human metabolite moisture detection is important in health monitoring and non-invasive ***,ultra-sensitive quantitative extraction of respiration information in real-time remains a great ***,chemiresistors based on imine-linked covalent organic framework(COF)films with dual-active sites are fabricated to address this issue,which demonstrates an amplified humidity-sensing signal *** regulation of monomers and functional groups,these COF films can be pre-engineered to achieve high response,wide detection range,fast response,and recovery *** the condition of relative humidity ranging from 13 to 98%,the COFTAPB-DHTA film-based humidity sensor exhibits outstanding humidity sensing perfor-mance with an expanded response value of 390 ***,the response values of the COF film-based sensor are highly linear to the relative humidity in the range below 60%,reflecting a quantitative sensing mechanism at the molecular *** on the dual-site adsorption of the(-C=N-)and(C-N)stretching vibrations,the revers-ible tautomerism induced by hydrogen bonding with water molecules is demonstrated to be the main intrinsic mechanism for this effective humidity *** addition,the synthesized COF films can be further exploited to effectively detect human nasal and oral breathing as well as fabric permeability,which will inspire novel designs for effective humidity-detection devices.

关键词： Covalent organic frameworks Humidity sensors Reversible tautomerism Non-invasive diagnosis Health monitoring

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A Novel Artificial Neuron-Like Gas Sensor Constructed from CuS Quantum Dots/Bi2S3 Nanosheets

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Nano-Micro Letters 2022年第1期14卷 167-181页

作者： Xinwei Chen Tao Wang Jia Shi Wen Lv Yutong Han min zeng Jianhua Yang Nantao Hu Yanjie Su Hao Wei Zhihua Zhou Zhi Yang Yafei Zhang Key Laboratory of Thin Film and Microfabrication(ministry of Education) Department of Micro/Nano ElectronicsSchool of Electronic Information and Electrical EngineeringShanghai Jiao Tong UniversityShanghai 200240People’s Republic of China

Real-time rapid detection of toxic gases at room temperature is particularly important for public health and environmental *** sensors based on conventional bulk materials often suffer from their poor surface-sensitive sites,leading to a very low gas adsorption ***,the charge transportation efficiency is usually inhibited by the low defect density of surface-sensitive area than that in the *** this work,a gas sensing structure model based on CuS quantum dots/Bi_(2)S_(3) nanosheets(CuS QDs/Bi_(2)S_(3) NSs)inspired by artificial neuron network is *** analysis by density functional calculation revealed that CuS QDs and Bi_(2)S_(3) NSs can be used as the main adsorption sites and charge transport pathways,***,the high-sensitivity sensing of NO_(2) can be realized by designing the artificial neuron-like *** experimental results showed that the CuS QDs with a size of about 8 nm are highly adsorbable,which can enhance the NO_(2) sensitivity due to the rich sensitive sites and quantum size *** Bi_(2)S_(3) NSs can be used as a charge transfer network channel to achieve efficient charge collection and *** neuron-like sensor that simulates biological smell shows a significantly enhanced response value(3.4),excellent responsiveness(18 s)and recovery rate(338 s),low theoretical detection limit of 78 ppb,and excellent selectivity for NO_(2).Furthermore,the developed wearable device can also realize the visual detection of NO2 through real-time signal changes.

关键词： Artificial neuron-like gas sensor Heterostructure design Nitrogen dioxide detection Wearable device

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Endothelial surface glycocalyx and vascular mechano-sensing and transduction

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医用生物力学 2013年第S1期28卷 15-16页

作者： Wanyi Yen Jinlin Yang min zeng John M.Tarbell Bingmei M.Fu Department of Biomedical Engineering the City College of the City University of New York

Introduction The endothelial cells(ECs)lining every blood vessel wall constantly expose to the mechanical forces generated by the blood *** EC responses to these hemodynamic forces play a critical role in the homeostasis of the circulatory *** addition to forming a transport barrier between the blood and vessel wall,vascular ECs play important roles in regulating circulation *** biochemical stimuli,blood flow induced(hemodynamic)mechanical stimuli,such as shear stress,pressure and circumferential stretch,modulate EC morphology and functions by activating mechanosensors,signaling pathways,and gene and protein *** EC responses to the hemodynamic forces(mechano-sensing and transduction)

关键词： transduction hemodynamic activating homeostasis constantly biochemical stimuli regulating stretch lining

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Nanchang:Herolc City with Glorious History

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Women of China 2021年第8期 60-62页

作者： zeng min(Photos) 不详

The anniversary of the founding of the People’s Liberation Army(PLA)of China is commemorated on August 1 each *** it is the birthplace of the PLA,Nanchang,in East China’s Jiangxi Province,is known as a"heroic city"w... 详细信息

关键词：英雄城历史文化名城绽放魅力红色南昌诞生地人民军队

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Assessment of health-related quality of life in Chinese patients with minimal hepatic encephalopathy

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World Journal of Gastroenterology 2007年第21期13卷 3003-3008页

作者： Zhi-Jun Bao De-Kai Qiu Xiong Ma Zhu-Ping Fan Gan-Sheng Zhang Yi-Qin Huang Xiao-Feng Yu min-De zeng Department of Gastroenterology Renji Hospital Shanghai Jiao Tong University School of Medicine Shanghai Institute of Digestive Disease Shanghai 200001 China Department of Gastroenterology Huadong Hospital Fudan University Shanghai 200010 China

AIM:To evaluate the health-related quality of life (HRQOL) based on the Chinese version of SF-36 and Chronic Liver Disease Questionnaire (CLDQ) in subjects with chronic hepatitis B,liver cirrhosis,including patients with minimal hepatic encephalopathy (MHE). METHODS:The SF-36 and CLDQ were administered to 160 healthy volunteers,20 subjects with chronic hepatitis B and 106 patients with cirrhosis (33 cases exhibited MHE). HRQOL scores were compared among the different study groups. The SF-36 includes eight health concepts:physical functioning,role-physical,body pain,general health,vitality,social functioning,role-emotion,and mental health. Six domains of CLDQ were assessed:abdominal symptoms,fatigue,systemic symptoms,activity,emotional function and worry. RESULTS:Compared with healthy controls (96.9 ± 4.5,86.6 ± 18.4,90.1 ± 12.5,89.0 ± 5.7,87.5 ± 4.3,95.8 ± 7.1,88.5 ± 15.9,88.7 ± 5.2 in SF-36 and 6.7 ± 0.5,6.1 ± 0.6,6.3 ± 0.6,6.5 ± 0.5,6.3 ± 0.5,6.8 ± 0.4 in CLDQ),patients with chronic hepatitis B (86.3 ± 11.0,68.8 ± 21.3,78.9 ± 14.4,60.8 ± 10.5,70.8 ± 8.6,76.1 ± 12.6,50.0 ± 22.9,72.2 ± 10.6 and 5.5 ± 1.0,4.5 ± 1.0,5.2 ± 1.1,5.3 ± 0.9,4.8 ± 0.9,4.9 ± 1.0) and cirrhosis (52.8 ± 17.4,32.8 ± 27.9,61.6 ± 18.9,30.2 ± 18.3,47.9 ± 20.1,54.0 ± 19.2,28.9 ± 26.1,51.1 ± 17.8 and 4.7 ± 1.2,3.9 ± 1.2,4.7 ± 1.2,4.7 ± 1.3,4.7 ± 1.0,4.4 ± 1.1) had lower HRQOL on all scales of the SF-36 and CLDQ (P < 0.01 for all). Increasing severity of liver cirrhosis (based on the Child-Pugh score/presence or absence of MHE) was associated with a decrease in most components of SF-36 and CLDQ,especially ***:The Chinese version of SF-36 along with CLDQ is a valid and reliable method for testing MHE in patients with liver cirrhosis. Cirrhosis and MHE are associated with decreased HRQOL.

关键词： minimal hepatic encephalopathy Liver cirrhosis Health-related quality of life Chronic hepatitis B Chinese

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