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Progress of d^0 magnetism in SiC

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Journal of Semiconductors 2017年第3期38卷 100-109页

作者： Yutian Wang Chenguang Liu yuming zhang School of Microelectronics Xidian University and Key Laboratory of Wide Band-Gap Semiconductor Materials and DevicesXi'an 710071 China

The properties of defect-induced ferromagnetism（d^0magnetism） in SiC belong to carbon-based material which has been systematically investigated after *** this paper,we reviewed our research progress about d^0 magnetism in two aspects,i.e.,magnetic source and magnetic coupling *** V_（Si）V_C divacancies have been evidenced as the probable source of d^0 magnetism in *** trace the ferromagnetic source in microscopic and electronic view,the p electrons of the nearest-neighbor carbon atoms,which are around the V_（Si）V_C divacancies,are *** magnetic coupling mechanism,a higher divacancy concentration leads to stronger paramagnetic interaction but not stronger ferromagnetic *** the d^0 magnetism can probably be explained as a local effect which is incapable of scaling up with the volume.

关键词： SiC d0 magnetism graphite

4H-Si C monolithic Darlington transistors with slight current gain drop at high collector current density

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Science China(Technological Sciences) 2018年第8期61卷 1238-1243页

作者： YUAN Lei SONG QingWen TANG XiaoYan zhang HongPeng zhang YiMeng YANG Fei GUO LiXin zhang YiMen zhang yuming Key Laboratory of Wide Band Gap Semiconductor Materials and Devices School of Microelectronics Xidian University State Key Laboratory of Advanced Power Transmission Technology Global Energy Interconnection Research Institute Co. Ltd. School of Physics and Optoelectronic Engineering Xidian University

Profit from high current gain features, 4 H-Si C power Darlington transistor has the capacity for handling high current transmission. In this paper, monolithic Darlington transistors were fabricated using a simultaneous formation process for both n-type(emitter) and p-type(base) ohmic contact. The isolated device shows current gain of 1061 and 823 with collector current density(JC) increasing from 200 to 800 A/cm2, exhibiting a slight current gain drop at high JC. By extracting the interface state density(Dit) between Si O2 and p-type 4 H-Si C, it is found that this advantage owes to the improvement of the shallow bulk minority carrier lifetime in base region. Furthermore, ISE-TCAD(technology computer aided design) simulation was carried out to study the relationship between base minority lifetime and the current gain, from which the total base minority lifetime is estimated to be 48 ns. The open base breakdown voltage(BVCEO) is 850 V at a leakage current of 2 μA due to the electric filed crowding at the isolation bottom between drive bipolar junction transistor(BJT) and output BJT. To solve this, non-isolated devices were also fabricated with improved BVCEOof 2370 V, indicating the superior potential of 4 H-Si C monolithic Darlington transistors for high power application, while the current gain is deceased to 420, which needs further improvement.

关键词： monolithic Darlington transistors Gummel characteristic lifetime improvement breakdown voltage

Improving the estimate of wind energy input into the Ekman layer within the Antarctic Circumpolar Current

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Acta Oceanologica Sinica 2013年第3期32卷 19-27页

作者： zhang yuming WU Kejian zhang Xiaoshuang BI Fan SONG Zhaoyang LIU Shouhua Physical Oceanography Laboratory Ocean University of China Key Laboratory of Marine Environmental Information Technology State Oceanic AdministrationNational Marine Data and Information Service National Marine Data & Information Service

Based on the data and method offered by Liu et al. （2009）, the direct wind and Stokes drift-induced energy inputs into the Ekman layer within the Antarctic Circumpolar Current （ACC） area are reestimated since the results of the former have been proved to be underestimated. And the result shows that the total rate of energy input into the Ekman-Stokes layer within the ACC area is 852.41 GW, including 649.75 GW of direct wind energy input （76%） and 202.66 GW of Stoke drift-induced energy input （24%）. Total increased energy input, due to wave-induced Coriolis-Stokes forcing added to the classical Ekman model, is 52.05 GW, accounting for 6.5% of the wind energy input into the classical Ekman layer. The long-term variability of direct wind and Stokes drift-induced energy inputs into the Ekman layer within the ACC is also investigated, and the result shows that the Stokes drift hinders the decadal increasing trend of direct wind energy input. Meanwhile, there is a period of 4-5 a in the energy spectrums, as same as the Antarctic circumpolar wave.

关键词： energy input Ekman-Stokes layer Coriolis-Stokes forcing Antarctic Circumpolar Current

Deep Spectrum Prediction in High Frequency Communication Based on Temporal-Spectral Residual Network

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China Communications 2018年第9期15卷 25-34页

作者： Ling Yu Jin Chen yuming zhang Huaji Zhou Jiachen Sun College of Communications Engineering Army Engineering University of PLA Nanjing 210000 China Science and Technology on Communication Information Security Control Laboratory Jiaxing 314033 China

High frequency(HF) communication is widely spread due to some merits like easy deployment and wide communication coverage. Spectrum prediction is a promising technique to facilitate the working frequency selection and enhance the function of automatic link establishment. Most of the existing spectrum prediction algorithms focus on predicting spectrum values in a slot-by-slot manner and therefore are lack of timeliness. Deep learning based spectrum prediction is developed in this paper by simultaneously predicting multi-slot ahead states of multiple spectrum points within a period of time. Specifically, we first employ supervised learning and construct samples depending on longterm and short-term HF spectrum data. Then, advanced residual units are introduced to build multiple residual network modules to respectively capture characteristics in these data with diverse time scales. Further, convolution neural network fuses the outputs of residual network modules above for temporal-spectral prediction, which is combined with residual network modules to construct the deep temporal-spectral residual network. Experiments have demonstrated that the approach proposed in this paper has a significant advantage over the benchmark schemes.

关键词： HF communication deep learning spectrum prediction temporal-spectral residual network

Comparative kinetics of coal and oil shale pyrolysis in a micro fluidized bed reaction analyzer

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Carbon Resources Conversion 2019年第3期2卷 217-224页

作者： yuming zhang Mengxuan Zhao Rongxuan Linghu Chengxiu Wang Shu zhang State Key Laboratory of Heavy Oil Processing College of Mechanical and Transportation EngineeringChina University of Petroleum-BeijingBeijing 102249PR China College of Materials Science and Engineering Nanjing Forestry UniversityNanjing 210037JiangsuPR China

The characteristics and kinetics of coal and oil shale pyrolysis were comparatively studied by using a micro fluidized bed reaction analyzer(MFBRA).The isothermal differential model was first applied to calculate the kinetic parameters of activation energy and frequency factor according to the major gas components during *** results showed that the major gas components released from coal and oil shale under the isothermal condition had different initiating and ending time points,and the difference was more significant under the programmed heating *** shrinking core model allowed better fitting relevance for the coal pyrolysis,while the three-dimension model was more suitable for oil shale pyrolysis,indicating that the gases from the pyrolysis process of coal and oil shale might go through different reaction *** activation energy of oil shale pyrolysis was 36.96 kJ·mol^(−1),larger than the value of pyrolysis of the two coals,which was 21.16 and 32.17 kJ·mol^(−1),*** above results justified that the oil shale pyrolysis with high ash contents was somehow more difficult to take place in terms of higher activation energy and the MFBRA could be a useful tool to give some insight into the intrinsic kinetics and reaction mechanisms of coal and oil shale pyrolysis.

关键词： Micro fluidized bed reaction analyzer Coal Oil shale Pyrolysis Kinetics

金银花提取物对小鼠阿霉素肝脏损伤的保护作用

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南方医科大学学报 2024年第8期44卷 1571-1581页

作者：张钰明夏士程张淋淋陈梦茜刘晓婧高琴叶红伟蚌埠医科大学生理学教研室安徽蚌埠233000 蚌埠医科大学心脑血管疾病基础与临床蚌埠医科大学重点实验室安徽蚌埠233000 蚌埠医科大学临床医学院安徽蚌埠233000

目的通过网络药理学与分子对接技术探讨金银花对阿霉素(DOX)肝脏损伤的保护作用和机制,并运用DOX诱导小鼠肝脏损伤实验进行验证。方法通过网络药理学方法获得金银花靶点与疾病靶点之间的交集基因。利用STRING数据库构建交集基因PPI网络... 详细信息

目的通过网络药理学与分子对接技术探讨金银花对阿霉素(DOX)肝脏损伤的保护作用和机制,并运用DOX诱导小鼠肝脏损伤实验进行验证。方法通过网络药理学方法获得金银花靶点与疾病靶点之间的交集基因。利用STRING数据库构建交集基因PPI网络,利用Cytoscape软件进行分析,筛选核心靶点。采用DAVID数据库进行生物信息学分析,分子对接技术对核心成分和核心靶点进行验证。运用DOX诱导小鼠肝脏损伤验证网络药理学的预测结果。检测小鼠血清ALT、AST水平和肝脏组织HYP、ROS水平,HE染色和Masson染色观察肝脏组织病理变化,ELISA检测肝脏组织TNF-α、IL-6、COL-IV水平,Western blotting检测肝脏组织P53蛋白表达水平。结果从交集的43个基因中筛选出12个核心靶点,涉及癌症通路、IL-17信号通路、TNF等信号通路。分子对接结果显示,10个核心成分可以与不同的核心靶点结合。小鼠实验显示,与Sham组相比,DOX组血清AST和ALT水平升高(P<0.001);HE和Masson染色显示肝脏损伤和肝脏纤维化,ROS、TNF-α、IL-6、HYP、COL-IV和P53蛋白水平升高(P<0.001)。与DOX组相比,金银花处理组血清AST和ALT水平降低(P<0.001),肝脏损伤和肝脏纤维化改善,肝脏组织ROS、TNF-α、IL-6、HYP和COL-IV水平和P53蛋白表达降低(P<0.001),肝脏组织氧化应激、炎症和纤维化均减轻。结论金银花可通过作用于Trp53、TNF、IL-6靶点减轻肝脏氧化应激、炎症和纤维化程度,减轻DOX诱导的肝脏损伤。

关键词：网络药理学金银花阿霉素肝脏损伤氧化应激肝脏纤维化炎症

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PTBD联合体外辅助胆汁入肠治疗恶性梗阻性黄疸患者疗效研究

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实用肝脏病杂志 2024年第4期27卷 619-622页

作者：杨丽花丁凌张玉明长江航运总医院超声影像科武汉市430014 三峡大学附属仁和医院超声科

目的观察采用经皮肝穿刺胆道引流(PTBD)联合体外辅助胆汁入肠治疗恶性梗阻性黄疸患者的疗效。方法2019年9月~2022年9月我院诊治的恶性梗阻性黄疸患者100例(其中胆管细胞癌42例、胰头癌35例、胆囊癌23例),被随机分为对照组50例和观察组50... 详细信息

目的观察采用经皮肝穿刺胆道引流(PTBD)联合体外辅助胆汁入肠治疗恶性梗阻性黄疸患者的疗效。方法2019年9月~2022年9月我院诊治的恶性梗阻性黄疸患者100例(其中胆管细胞癌42例、胰头癌35例、胆囊癌23例),被随机分为对照组50例和观察组50例,分别采用单纯的PTBD治疗或在PTBD治疗的基础上,联合体外辅助胆汁入肠治疗。使用PUZS-600A型全自动生化分析仪检测血生化指标。结果在治疗2周后,观察组体质指数、血钠、血钾和血清白蛋白水平分别为(20.3±2.2)kg/m^(2)、(144.8±14.6)mmol/L、(4.6±0.5)mmol/L和(35.2±4.2)g/L,显著高于对照组[分别为(16.9±1.8)kg/m^(2)、(138.2±10.7)mmol/L、(4.3±0.4)mmol/L和(30.1±4.9)g/L,P0.05)。结论采用PTBD联合体外辅助胆汁入肠治疗恶性梗阻性黄疸患者有利于短期改善营养状况和肝功能指标,作为姑息治疗,值得临床应用。

关键词：恶性梗阻性黄疸经皮肝穿刺胆道引流体外辅助胆汁入肠治疗

Study of relationship between wave transport and sea surface temperature anomaly(SSTA) in the tropical Pacific

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Acta Oceanologica Sinica 2016年第9期35卷 58-66页

作者： SHI Yongfang WU Kejian ZHU Xianye YANG Fan zhang yuming Key Laboratory of Marine Science and Numerical The First Institute of OceanographyState Oceanic Administration College of Oceanic and Atmospheric Sciences Ocean University of China National Marine Environmental Monitoring Center State Oceanic Administration

Large-scale water transport is one of the key factors that affect sea surface temperature anomaly（SSTA） in the eastern equatorial Pacific（EEP）.The relationship between the wave transport in the tropical Pacific and the SSTA in the EEP is examined by different methods,including band-pass filtering,period analysis,correlation analysis,significant analysis,and empirical orthogonal function（EOF） *** have found that the eastward shift of the wave transport anomaly in the tropical Pacific,with a period of 2 a and enhancing the transport of warm waters from the western Pacific warm pool,precedes the increase of sea surface temperature（SST） in the *** wave transport and the SSTA in the EEP have a maximum correlation of 0.65 with a time-lag of 6 months（transport variation precedes the temperature）.The major periods（3.7 a and 2.45 a） of the wave transport variability,as revealed by the EOF analysis,appear to be consistent with the SSTA oscillation cycle in the *** on the first occurrence of a significant SSTA in the Ni？o 3 region（5°S–5°N,90°–150°W）,two types of warm events are *** wave transport anomalies in two types present predominantly the west anomaly in the tropical Pacific,it is that the wave transport continues transport warm water from west to east before the onset of the warm *** impact of wave-induced water transport on the SSTA in the EEP is confirmed by the heat flux of the wave *** wave transport exerts significant effect on the SSTA variability in the EEP and thus is not neglectable in the further studies.

关键词： wave transport eastern equatorial Pacific sea surface temperature anomaly warm events

Nest site characteristics and nest loss of Marsh Grassbird at Zhalong National Nature Reserve, China

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Journal of Forestry Research 2015年第3期26卷 785-790页

作者： Qiang Wang Xuehong Zhou Fengshan Li yuming zhang Feng Li College of Wildlife Resource Northeast Forestry University Key Laboratory of Wetland Ecology and Environment CAS International Crane Foundation E-11376 Shady Lane RoadBaraboo WI 53913 USA

The Marsh Grassbird Locustella pryeri is an uncommon songbird endemic to East Asia. Suitable nest- site selection can minimize nest loss, especially for open- cup and ground nesting passerines. We located and mon- itored 66 Marsh Grassbird nests during 2004-2006 in Zhalong National Nature Reserve, northeast China, to identify characteristics of preferred nest sites. Marsh Grassbird nested mainly at sites with dense vegetation cover, high undergrowth and dry standing reed stalks, as well as small shallow ponds or rivers. Nests were more successful when they were placed higher above ground in patches with greater litter thickness. Predation and flooding were the leading causes of nest failure, accounting for at least 33 and 25 % of 24 nests lost, respectively. We ad- vocate retention of some unharvested reed patches and implementation of irrigation strategies that avoid increas- ing water levels during the breeding period （May-July） of Marsh Grassbirds.

关键词： Flooding Japanese Marsh Warbler.Locustella pryeri Nest site Predation Zhalong