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Chinese Physics Letters 2014年第3期31卷 129-132页

作者： YU Xin-Xin NI Jin-Yu LI Zhong-Hui KONG Cen ZHOU jian-jun DONG Xun pan Lei KONG Yue-Chan CHEN Tang-Sheng Science and Technology on Monolithic Integrated Circuits and Modules Laboratory Nanjing Electronic Devices Institute Nanjing 210016

We report on the high breakdown performance of AlGaN/GaN high electron mobility transistors （HEMTs） grown on 4-inch silicon substrates. The HEMT structure including three Al-content step-graded AlGaN transition layers has a total thickness of 2.7 μm. The HEMT with a gate width WG of 300 μm acquires a maximum off-state breakdown voltage （BV） of 550 V and a maximum drain current of 527 mA/mm at a gate voltage of 2 V. It is found that BV is improved with the increase of gate-drain distance LGD until it exceeds 8 μm and then BV is tended to saturation. While the maximum drain current drops continuously with the increase of LGD. The HEMT with a WG of 3 mm and a LGD of 8 μm obtains an off-state BV of 500 V. Its maximum leakage current is just 13 μA when the drain voltage is below 400 V. The device exhibits a maximum output current of 1 A with a maximum transconductance of 242 mS.

关键词： High electron mobility transistors

Radiochemical separation of thorium from ^(18)O inducedreaction with natural uranium

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Nuclear Science and Techniques 2001年第2期12卷 81-86页

作者： YANG Wei-Fan, YUAN Shuang-Gui, XIONG Bing, XU Yan-Bing, HE jian-jun, pan Qiang-Yan, MA Tao-Tao Institute of Modern Physics, the Chinese Academy of Sciences, Lanzhou 730000 中科院近代物理所甘肃兰州 730000

A radiochemical procedure used to separate and purify trace concentration thorium produced in heavy ion reaction with uranium targets is presented. The procedure can rapidly yield thorium fraction suitable for gamma-ray spectroscopy studies. The resultant gamma-ray spectra showed that Th was isolated from a large number of elements produced in the reaction, and there were only a few contaminating activities of isotopes of Sc, Cd, In, etc. The decontamination factors for the main reaction products are given.

关键词：钍放射化学分离天然铀

基于改进自适应神经模糊推理模型的回流焊参数设定方法

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上海交通大学学报 2011年第12期45卷 1741-1746页

作者：沙建军潘尔顺上海交通大学机械与动力工程学院上海200240

复杂制造过程中,系统参数往往呈现动态、非线性特征,以回流焊过程为例,针对现有参数设定方法效率和精度不足的问题,提出了一种基于改进自适应神经模糊推理模型的在线参数设定方法.引入了神经网络预测器来增强模糊神经网络的自适应能力... 详细信息

复杂制造过程中,系统参数往往呈现动态、非线性特征,以回流焊过程为例,针对现有参数设定方法效率和精度不足的问题,提出了一种基于改进自适应神经模糊推理模型的在线参数设定方法.引入了神经网络预测器来增强模糊神经网络的自适应能力和非线性逼近能力,通过最近邻聚类算法对模糊规则的参数和结构进行调整和在线更新,以提高模糊推理的精度,增强系统的容错性和鲁棒性.以回流焊过程参数设定过程为背景,建立仿真实验.结果表明,所提出方法可有效实现非线性输入输出系统参数的快速及准确的设定.

关键词：自适应神经模糊推理系统预测器最近邻聚类算法回流焊在线参数设定

Significant loss of soil inorganic carbon at the continental scale

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National Science Review 2022年第2期9卷 13-20页

作者： Xiao-Dong Song Fei Yang Hua-Yong Wu Jing Zhang De-Cheng Li Feng Liu Yu-Guo Zhao Jin-Ling Yang Bing Ju Chong-Fa Cai Biao Huang Huai-Yu Long Ying Lu Yue-Yu Sui Qiu-Bing Wang Ke-Ning Wu Feng-Rong Zhang Ming-Kui Zhang Zhou Shi Wan-Zhu Ma Gang Xin Zhi-Ping Qi Qing-Rui Chang En Ci Da-Gang Yuan Yang-Zhu Zhang jun-Ping Bai Jia-Ying Chen Jie Chen Yin-jun Chen Yun-Zhong Dong Chun-Lan Han Ling Li Li-Ming Liu jian-jun pan Fu-Peng Song Fu-jun Sun Deng-Feng Wang Tian-Wei Wang Xiang-Hua Wei Hong-Qi Wu Xia Zhao Qing Zhou Gan-Lin Zhang State Key Laboratory of Soil and Sustainable Agriculture Institute of Soil Science Chinese Academy of Sciences College of Advanced Agricultural Sciences University of Chinese Academy of Sciences College of Resources and Environment Huazhong Agricultural University Institute of Agricultural Resources and Regional Planning Chinese Academy of Agricultural Sciences College of Natural Resources and Environment South China Agricultural University Northeast Institute of Geography and Agroecology Chinese Academy of Sciences College of Land and Environment Shenyang Agricultural University School of Land Science and Technology China University of Geosciences College of Land Science and Technology China Agricultural University College of Environmental and Resource Sciences Zhejiang University Institute of Digital Agriculture Zhejiang Academy of Agricultural Sciences College of Agriculture Heilongjiang Bayi Agricultural University Tropical Crops Genetic Resources Institute Chinese Academy of Tropical Agricultural Sciences College of Natural Resources and Environment Northwest A & F University College of Resources and Environment Southwest University College of Resources Sichuan Agricultural University College of Resources and Environment Hunan Agricultural University Institute of Agricultural Product Quality Standard and Testing Research Tibet Academy of Agricultural and Animal Husbandry Sciences School of Agricultural Sciences Zhengzhou University Institute of Agriculture Environment and Resources Research Shanxi Academy of Agricultural Sciences College of Resources and Environment Henan Agricultural University College of Resources and Environment China Agricultural University College of Resources and Environmental Sciences Nanjing Agricultural University College of Resources and Environment Shandong Agricultural University Agricultural College Guangxi University College of Grassland and Environment Science Xinjiang Agricultural University College of Geographical Science Qinghai Normal University

Widespread soil acidification due to atmospheric acid deposition and agricultural fertilization may greatly accelerate soil carbonate dissolution and ***,to date,few studies have addressed these ***,we use meta-analysis and nationwide-survey datasets to investigate changes in soil inorganic carbon(SIC) stocks in *** observe an overall decrease in SIC stocks in topsoil(0-30 cm)(11.33 g C m-2yr-1) from the 1980 s to the 2010 *** SIC stocks have decreased by～8.99±2.24%(1.37±0.37 Pg C).The average SIC losses across China(0.046 Pg C yr-1) and in cropland(0.016 Pg C yr-1) account for～17.6%-24.0% of the terrestrial C sink and 57.1% of the soil organic carbon sink in cropland,*** deposition and climate change have profound influences on SIC *** estimate that～19.12%-19.47% of SIC stocks will be further lost by *** consumption of SIC may offset a large portion of global efforts aimed at ecosystem carbon sequestration,which emphasizes the importance of achieving a better understanding of the indirect coupling mechanisms of nitrogen and carbon cycling and of effective countermeasures to minimize SIC loss.

关键词： China soil inorganic carbon stocks global change carbonate soil acidification

华南新元古代裂谷盆地演化——Rodinia超大陆解体的前奏

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矿物岩石 2001年第3期21卷 135-145页

作者：王剑刘宝珺潘桂棠中国地质调查局成都地调中心四川成都610082

沉积学研究表明 ,华南新元古代沉积盆地具典型裂谷盆地沉积演化特征。代表裂谷盆地早期形成阶段的成因相组合有 :冲洪积相组合、陆相 (或海相 )火山岩及火山碎屑岩相组合、滨浅海相沉积组合、淹没碳酸盐台地及欠补偿盆地黑色页岩相组合 ... 详细信息

沉积学研究表明 ,华南新元古代沉积盆地具典型裂谷盆地沉积演化特征。代表裂谷盆地早期形成阶段的成因相组合有 :冲洪积相组合、陆相 (或海相 )火山岩及火山碎屑岩相组合、滨浅海相沉积组合、淹没碳酸盐台地及欠补偿盆地黑色页岩相组合 ;而代表中、后期形成阶段的成因相组合有 :滨岸边缘相至深海相组合 ,冰期冰积岩相组合、碳酸盐岩及碳硅质细碎屑岩相组合。华南裂谷盆地岩相古地理演化经历了 5个重要的时期 ,整体上反映了一个由陆变海、由地堑 -地垒相间盆地变广海盆地、由浅海变深海、盆地由小变大的演化过程。裂谷盆地的形成经历了裂谷基的形成、地幔柱作用与裂谷体的形成、被动沉降(下拗 )与裂谷盖的形成三个阶段。华南裂谷盆地的形成演化与 Rodinia超大陆在新元古代时期的裂解作用密切相关。

关键词：华南新元古代裂谷盆地 Rodinia超大陆沉积盆地裂解作用

Unlocking the future:Mitochondrial genes and neural networks in predicting ovarian cancer prognosis and immunotherapy response

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World Journal of Clinical Oncology 2025年第1期16卷 43-52页

作者： Zhi-jian Tang Yuan-Ming pan Wei Li Rui-Qiong Ma jian-Liu Wang Department of Obstetrics and Gynecology Peking University People’s HospitalBeijing 100044China Cancer Research Center Beijing Chest HospitalBeijing 101149China Department of Thoracic Surgery Sichuan Provincial People's HospitalChengdu 610072Sichuan ProvinceChina

BACKGROUND Mitochondrial genes are involved in tumor metabolism in ovarian cancer(OC)and affect immune cell infiltration and treatment *** To predict prognosis and immunotherapy response in patients diagnosed with OC using mitochondrial genes and neural *** Prognosis,immunotherapy efficacy,and next-generation sequencing data of patients with OC were downloaded from The Cancer Genome Atlas and Gene Expression *** genes were sourced from the MitoCarta3.0 *** discovery cohort for model construction was created from 70% of the patients,whereas the remaining 30% constituted the validation *** the expression of mitochondrial genes as the predictor variable and based on neural network algorithm,the overall survival time and immunotherapy efficacy(complete or partial response)of patients were *** In total,375 patients with OC were included to construct the prognostic model,and 26 patients were included to construct the immune efficacy *** average area under the receiver operating characteristic curve of the prognostic model was 0.7268[95% confidence interval(CI):0.7258-0.7278]in the discovery cohort and 0.6475(95%CI:0.6466-0.6484)in the validation *** average area under the receiver operating characteristic curve of the immunotherapy efficacy model was 0.9444(95%CI:0.8333-1.0000)in the discovery cohort and 0.9167(95%CI:0.6667-1.0000)in the validation *** The application of mitochondrial genes and neural networks has the potential to predict prognosis and immunotherapy response in patients with OC,providing valuable insights into personalized treatment strategies.

关键词： Ovarian cancer Mitochondria Prognosis Immunotherapy Neural network

Observation of topological charge transformations in acoustic vortex using passive periodic systems

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Science China(Physics,Mechanics & Astronomy) 2025年第1期Mechanics & Astronomy) .卷 140-147页

作者： Di-Chao Chen Xie Liu Changqing Xu Da-jian Wu Ying Cheng Xiao-jun Liu School of Physics and Technology Nanjing Normal University Key Laboratory of Modern Acoustics School of Physics Nanjing University

Vortex transmutation utilizes a periodic system, which not only enables the alteration of the topological charge(TC) of unstable input vortices but also facilitates their transformation into stable structures. This approach is crucial for investigating the characteristics of vortices in various wave systems. Here, we achieve acoustic vortex TC transmutation by employing a welldesigned dual-structured plate external system(DPES). The interactions between the acoustic vortex and the finite-order discrete rotational symmetry lead to the transformation of its topological charge when complete rotational symmetry is broken to Nthorder discrete symmetry. Our results experimentally demonstrate the acoustic vortex TC transmutation based on passive artificial structures, enabling numerous applications in particle manipulation and information multiplexing as well as advancing our understanding and control over free-space acoustic vortices.

关键词： acoustic vortex topological charge transformation artificial structure

Staged dendrite suppression for high safe and stable lithium-sulfur batteries

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Journal of Energy Chemistry 2025年第1期100卷 674-683页

作者： jun jiang Zhenjie Lu Yanwen Ding Shujun Liu Zhijie Qi Tian Tang Yunfan Zhang Zhiyuan Ma Jingwen Sun Liang Xue Wenyao Zhang pan Xiong Xin Wang junwu Zhu Yongsheng Fu Key Laboratory for Soft Chemistry and Functional Materials of Ministry of Education Nanjing University of Science and Technology jiangsu Pylon Battery Co.Ltd

The unavoidable dendrite growth and shuttle effect have long been stranglehold challenges limiting the safety and practicality of lithium-sulfur ***,we propose a dual-action strategy to address the lithium dendrite issue in stages by constructing a multifunctional surface-negatively-charged nanodiamond layer with high ductility and robust puncture resistance on polypropylene （PP） *** uniformly loaded compact negative layer can not only significantly enhance electron transmission efficiency and promote uniform lithium deposition,but also reduce the formation of dendrite during early deposition *** importantly,under the strong puncture stress encountered during the deterioration of lithium dendrite growth under limiting current,the high ductility and robust puncture resistance（145.88 MPa） of as-obtained nanodiamond layer can effectively prevent short circuits caused by unavoidable lithium *** Li||Li symmetrical cells assembled with nanodiamond layer modified PP demonstrated a stable cycle of over 1000 h at 2 mA cm-2with a polarization voltage of only 29.3 ***,the negative charged layer serves as a physical barrier blocking lithium polysulfide ions,effectively mitigating capacity *** improved cells achieved a capacity decay of only 0.042%per cycle after 700 cycles at 3 C,demonstrating effective suppression of dendrite growth and capacity attenuation,showing promising prospect.

关键词： Lithium-sulfur batteries Staged dendrite suppression Shuttle effect Surface-negatively-charged nanodiamond

Effects of Bifidobacterium lactis BLa80 on fecal and mucosal flora and stem cell factor/c-kit signaling pathway in simulated microgravity rats

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World Journal of Gastroenterology 2025年第1期31卷 93-109页

作者： Ping Zhang Ying Zhu Pu Chen Tong Zhou Zhe-Yi Han jun Xiao jian-Feng Ma Wen Ma Peng Zang Ying Chen Graduate School Hebei North UniversityZhangjiakou 075000Hebei ProvinceChina Key Laboratory of Aerospace Nutrition and Food Engineering China Astronaut Research and Training CenterBeijing 100094China Department of Gastroenterology The Air Force Medical CenterBeijing 100142China Department of Blood Transfusion Air Force Medical CenterBeijing 100142China

BACKGROUND Simulated microgravity environment can lead to gastrointestinal motility *** pathogenesis of gastrointestinal motility disorders is closely related to the stem cell factor(SCF)/c-kit signaling pathway associated with intestinal flora and Cajal stromal ***,intestinal flora can also affect the regulation of SCF/c-kit signaling pathway,thus affecting the expression of Cajal stromal *** cells are the pacemakers of gastrointestinal *** To investigate the effects of Bifidobacterium lactis(***)BLa80 on the intestinal flora of rats in simulated microgravity and on the gastrointestinal motility-related SCF/c-kit *** The internationally recognized tail suspension animal model was used to simulate the microgravity environment,and 30 rats were randomly divided into control group,tail suspension group and drug administration tail suspension group with 10 rats in each group for a total of 28 *** tail group was given *** BLa80 by intragastric administration,and the other two groups were given water intragastric administration,the concentration of intragastric administration was 0.1 g/mL,and each rat was 1 mL/***&eosin staining was used to observe the histopathological changes in each segment of the intestine of each group,and the expression levels of SCF,c-kit,extracellular signal-regulated kinase(ERK)and p-ERK in the gastric antrum of each group were detected by Western blotting and *** fecal flora and mucosal flora of rats in each group were detected by 16S *** Simulated microgravity resulted in severe exfoliation of villi of duodenum,jejunum and ileum in rats,marked damage,increased space between villi,loose arrangement,shortened columnar epithelium of colon,less folds,narrower mucosal thickness,reduced goblet cell number and crypts,and significant improvement after probiotic *** microgravity reduced the expressions of SCF and c-kit,and increased the express

关键词： Simulated microgravity Rat Intestinal flora Gastrointestinal motility Stem cell factor/c-kit signaling pathway

Sparse Signal Recovery via Exponential Metric Approximation

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Tsinghua Science and Technology 2017年第1期22卷 104-111页

作者： jian pan jun Tang Wei Zhu Department of Electronic Engineering Tsinghua University Beijing 100084China

Sparse signal recovery problems are common in parameter estimation, image processing, pattern recognition, and so on. The problem of recovering a sparse signal representation from a signal dictionary might be classified as a linear constraint l_0-quasinorm minimization problem, which is thought to be a Non-deterministic Polynomial-time（NP）-hard problem. Although several approximation methods have been developed to solve this problem via convex relaxation, researchers find the nonconvex methods to be more efficient in solving sparse recovery problems than convex methods. In this paper a nonconvex Exponential Metric Approximation（EMA）method is proposed to solve the sparse signal recovery problem. Our proposed EMA method aims to minimize a nonconvex negative exponential metric function to attain the sparse approximation and, with proper transformation,solve the problem via Difference Convex（DC） programming. Numerical simulations show that exponential metric function approximation yields better sparse recovery performance than other methods, and our proposed EMA-DC method is an efficient way to recover the sparse signals that are buried in noise.

关键词： sparse recovery exponential metric approximation sparsity tolerance DC optimization signal-to-noiseratio