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Extended-source broken gate tunnel FET for improving direct current and analog/radio-frequency performance

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Chinese Physics B 2021年第7期30卷 624-630页

作者： Hui-Fang Xu Wen Sun na Wang Institute of Electrical and Electronic Engineering Anhui Science and Technology UniversityFengyang 233100China

The various advantages of extended-source(es),broken gate(BG),and hetero-gate-dielectric(HGD)technology are blended together for the proposed tunnel field-effect transistor(esBG TFET)in order to enhance the direct-current and analog/radio-frequency *** source of the esBG TFET is extended into channel for the purpose of increasing the point and line tunneling in the device at the tunneling junction,and then,the on-state current for the esBG TFET *** influence of the source region length on the direct-current and radio-frequency performance parameters of the esBG TFET is analyzed in *** results show that the proposed TFET exhibits a high on-state current to off-state current ratio of 1013,large transconductance of 1200μS/μm,high cut-off frequency of 72.8 GHz,and high gain bandwidth product of 14.3 *** from these parameters,the esBG TFET also demonstrates high linearity distortion parameters in terms of the second-and third-order voltage intercept points,the third-order input interception point,and the third-order intermodulation ***,the esBG TFET greatly promotes the application potential of conventional TFETs.

关键词： extended-source broken gate radio-frequency performances tunnel field-effect transistor

Season-dependence of soil extracellular enzyme activities in a Pinus koraiensis forest on Changbai Mountain

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Journal of Forestry Research 2021年第4期32卷 1713-1722页

作者： Ning Wang Mengmeng Zhang na Zhao Fujuan Feng Min Zhao College of Life Sciences Northeast Forestry UniversityHarbin 150040People’s Republic of China College of Life Sciences Baicheng Normal UniversityBaicheng 137000People’s Republic of China College of Life Sciences Heilongjiang UniversityHarbin 150040People’s Republic of China

Changbai Mountain,central in the distribution of Pinus koraiensis,supports a virgin Korean pine forest with vertical gradient *** extracellular enzyme activity(EEA) and enzyme stoichiometry(es) are reliable indicators of the energy and nutrients utilized by microbial communities and of soil nutrient *** measured four representative soil EEAs(sucrase,cellulase,urease,acid phosphatase) at two soil layers(A:0-5 cm and B:5-10 cm)beneath Korean pine forest at five elevations on Changbai Mountain during growing *** vertical and seasonal variations of EEAs were analyzed by soil enzyme stoichiometry to quantify the role of soil microorganism in the nutrient cycling *** activities of four soil extracellular enzymes and the ratios of enzyme activity to soil microbial biomass carbon(EA/SMBC) did not vary with *** first partition point of multiple regression trees was in September,and the second branch was split by *** change had more influence on soil enzyme activity(A layer:75.6%;B layer:71.3%) than did change in elevation(A layer:7.8%;B layer:7.5%).Over one entire growing season,both vector length and vector angle were unchanged by elevation,but varied significantly by *** the soil physicochemical factors,available phosphorus and pH were the main factors affecting the four soil EE *** ratio of basal area of the coniferous tree to broad-leaved tree species(S_(con)/S_(br)),soil microbial biomass carbon(MBC) and nitrogen(MBN) influenced the four soil EE *** results of vector analysis revealed that C and N sources were generally sufficient,but P was limiting(vector angle> 45°).The vector angle for September was significantly higher than for other *** result verified that phosphorus was the limiting factor affecting soil microorganism function in nutrient metabolism and *** enzyme stoichiometry proved to be an efficient index for quantifying soil microorganismmediated nutrient cycling in t

关键词： Korean pine forest Soil extracellular enzyme Enzyme stoichiometry Seasonality Elevation

Differential Gene Expression in Response to Drought Stress in Maize Seedling

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Agricultural Sciences in China 2009年第7期8卷 767-776页

作者： DENG Xiao-feng FU Feng-ling NI na LI Wan-chen Maize Research Institute Sichuan Agricultural University/Key Laboratory of Crop Genetic Resources and Improvement Ministry of Education Ya＇an 625014 P.R. China

To provide the useful information for the choice of molecular marker used in marker-assisted selection of drought tolerance, it is necessary to find out more candidate genes and fulfill the information gaps in gene expression regulation under drought stress. In this study, we isolated four differentially expressed cDna fragments from leaves of a droughttolerant inbred line by suppression subtractive hybridization and reverse Northern hybridization, and validated their differential expression patterns among six inbred lines with different drought tolerance in response to drought stress by quantitative real-time PCR. Sequence similarity analysis indicated that two of four differentially expressed cDna showed homology to gene DegP encoding trypsin-like serine protease, and gene PGAM-i encoding cofactor-independent phosphoglyceromutase, respectively. Expressions of the genes corresponding to four cDna fragments was decreased at 6 h after drought stress treatment in most of the six inbred lines, and then returned to the control level with further stress in three of the tolerant inbred lines. The expression of the gene PGAM-i and the genes corresponding to fragments E4 and F4 were increased to a high level in tolerant inbred line 81565. In the two drought-sensitive inbred lines （Dan340 and es40）, the expression of these genes was still down-regulated. The probable mechanisms of these genes in response to drought stress were discussed. These results indicated that the drought-tolerant inbred lines upregulated the expression of the drought-tolerant candidate genes, in contrast, drought-sensitive inbred lines downregulated the expression of the genes.

关键词： DegP drought tolerance expression pattern maize PGAM-i

Organic geochemistry and petrology of source rocks from the Banqiao Sag, Bohai Bay Basin, China: Implications for petroleum exploration

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Petroleum Science 2022年第4期19卷 1505-1515页

作者： Xiang-Bai Liu Guang-Di Liu Wen-Ya Jiang Ze-Zhang Song na Wang State Key Laboratory of Petroleum Resources and Prospecting China University of PetroleumBeijing102249China College of Geosciences China University of PetroleumBeijing102249China Exploration and Development Research Institute Dagang Oilfield CompanyPetroChinaTianjin300280China

The organic geochemistry and petrology of source rocks determine the hydrocarbon generation potential of the Banqiao Sag. In this study, organic geochemistry and petrology were used to determine the abundance of organic matter(OM), OM type, OM maturity, and sedimentary environments of the source rocks, collected from Cenozoic Shahejie Formation, Banqiao Sag, Bohai Bay Basin, China. Vitrinite and liptinite are the main maceral composition of the source rocks, and range from 18% to 81% and from 2% to82% on a mineral matter free(MMF) basis, respectively. The values of vitrinite reflectance(Ro)(0.36%-1.20%) and the Tmaxvalues(397-486.C) show that the thermal maturity range from low mature to peak-maturity. The abundance of OM varies between 0.22% and 4.37%, suggesting that the source rocks of the Shahejie(es) Formation are mainly fair to good source rocks. The Rock-Eval pyrolysis results show that the source rocks have good petroleum generation potential. The amount of free hydrocarbons(S_1)and hydrocarbons generated from pyrolysis(S_(2)) range within 0.01-3.70 mg/g, and 0.04-29.17 mg/g. The hydrogen index(HI) varies between 18.18 and 741.13 mg HC/g TOC, with most of the samples appearing to be mainly Type II kerogen, and thereby exhibiting the ability to generate both oil and gas. The ratios of Pr/Ph, the cross plot of Pr/nC_(17)-Ph/nC_(18), the cross plot of C_(29)/C_(27)-Pr/Ph, and ternary of dibenzothiophene, dibenzofuran, and fluorene, indicate that the Shahejie Formation deposited in suboxic and weak reducing environments. The main biological source is from advanced plants. The maceral composition and rock pyrolysis data indicate the kerogen type is a humic type or mixed sapropelic-humic type. The source rocks of the Shahejie(es) Formation occur in the oil window, and the abundant organic richness,humic kerogen demonstrate that these rocks are effective oil and gas source rocks. The mudstone rocks in the Shahejie Formation are the main source of oil and gas and re

关键词： Lacustrine source rocks Petrology Biomarkers Depositional environment Banqiao Sag

Astronomical forcing and sedimentary noise modeling of lake-level changes in the Middle Eocene Chezhen Sag,Bohai Bay Basin,eastern China

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Frontiers of Earth Science 2024年第2期18卷 446-459页

作者： Xuwei LUAN Jinliang ZHANG na LI Tao CHEN Long SUN Xuecai ZHANG Faculty of Geographical Science Beijing Normal UniversityBeijing 100875China College of Geosciences China University of Petroleum(Beijing)Beijing 102249China Management Center of Oil and Gas Exploration Sinopec Shengli OilfieldDongying 257000China

The accurate determination of geological age is a key to understanding the history and process of paleolake evolution and oil and gas exploration in continental lake ***,improving the accuracy of geological age has always been a difficult scientific problem.A 609-m-thick,continuous lacustrine mudstone and sandstone succession in Chezhen Sag(eastern China)provides an ideal middle Eocene sedimentary record for establishing a high-resolution stratigraphic chronology *** on spectrum analysis and sliding window spectrum analysis of the natural gamma(GR)logging data of well Che 271(C271)in Chezhen Sag,the periods of 405 kyr and 40.1 kyr were filtered by a Gaussian bandpass filter,and a“floating”astrochronological time scale(ATS)was *** total number of 405 kyr eccentricity cycles were 13.6 and 40.1 kyr obliquity cycles were 138 which recorded from the upper member 4(es4U)to the member 3(es3)of the Eocene Shahejie Formation,and the depositional duration was 5.53 *** Coefficient(COCO)analysis and evolutionary Correlation Coefficient(eCoCo)analysis found that the optimal sedimentary rate of different *** noise simulation revealed the history of paleolake water changes in the Middle Eocene in the Chezhen Sag,according to which four sequences are *** study shows that the lake level change of Chezhen Sag in the middle Eocene shows prominent 1.2 Myr cycles and an antiphase well-coupled relationship with obliquity ***,we propose a model to explain the relationship between the orbital cycle and lake level change in the continental lake *** the obliquity of the earth increases,the middle and high latitudes of the earth will be closer to the sun,the direct sunlight will be higher,and the meridional sunshine will increase,thus accelerating the evaporation process of lake basin *** the seasonal changes are obvious(maximum period of 1.2 Myr ultra-long obliquity),this effect is more signific

关键词： Chezhen Sag cyclostratigraphy astrochronological time scale sedimentary noise

Psychometrics of chronic liver disease questionnaire in Chinese chronic hepatitis B patients

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World Journal of Gastroenterology 2013年第22期19卷 3494-3501页

作者： Kai-na Zhou Min Zhang Qian Wu Zhen-Hao Ji Xiao-Mei Zhang Gui-Hua Zhuang Department of Epidemiology and Biostatistics Xi'an Jiaotong University College of Medicine

AIM: To evaluate psychometrics of the Chinese (mainland) chronic liver disease questionnaire (CLDQ) in patients with chronic hepatitis B (CHB). METHODS: A cross-sectional sample of 460 Chinese patients with CHB was selected from the Outpatient Department of the Eighth Hospital of Xi'an, including CHB (CHB without cirrhosis) (n = 323) and CHB-related cirrhosis (n = 137). The psychometrics includes reliability, validity and sensitivity. Internal consistency reliability was measured using Cronbach's α. Convergent and discriminant validity was evaluated by item-scale correlation. Factorial validity was explored by principal component analysis with varimax rotation. Sensitivity was assessed using Cohen's effect size (es), and independent sample t test between CHB and CHB-related cirrhosis groups and between alanine aminotransferase (ALT) normal and abnormal groups after stratifying the disease (CHB and CHB-related cirrhosis).ResULTS: Internal consistency reliability of the CLDQ was 0.83 (range: 0.65-0.90). Most of the hypothesized item-scale correlations were 0.40 or over, and all of such hypothesized correlations were higher than the alternative ones, indicating satisfactory convergent and discriminant validity. Six factors were extracted after varimax rotation from the 29 items of CLDQ. The eligible Cohen's es with statistically significant independent sample t test was found in the overall CLDQ and abdominal, systematic, activity scales (CHB vs CHBrelated cirrhosis), and in the overall CLDQ and abdominal scale in the stratification of patients with CHB (ALT normal vs abnormal). CONCLUSION: The CLDQ has acceptable reliability, validity and sensitivity in Chinese (mainland) patients with CHB.

关键词： Chronic hepatitis B Chronic liver disease questionnaire Reliability Validity Sensitivity

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在滞尘影响下的植被叶片光谱变化特征研究

光谱学与光谱分析 2013年第10期33卷 2715-2720页

作者：罗娜娜赵文吉晏星首都师范大学三维信息获取与应用教育部重点实验室首都师范大学资源环境与地理信息系统北京市重点实验室香港理工大学土地测量及地理资讯学系

为建立以高光谱数据为基础的叶片滞尘质量反演模型,沿北京市区采集了30个大叶黄杨叶片样本。利用电子分析天平和光谱仪(analytical spectral devices ASD FieldSpec Pro)测定"除尘前"与"除尘后"叶片质量及光谱反射率曲线,以获取叶片尘... 详细信息

为建立以高光谱数据为基础的叶片滞尘质量反演模型,沿北京市区采集了30个大叶黄杨叶片样本。利用电子分析天平和光谱仪(analytical spectral devices ASD FieldSpec Pro)测定"除尘前"与"除尘后"叶片质量及光谱反射率曲线,以获取叶片尘埃量、光谱信息等数据。随后以传统意义和偏最小二乘(PLS)回归模型为基础,以探究空气尘埃量与光谱曲线之间可能存在的关系,阐述了叶片尺度上尘埃量对植物光谱特征的影响。结果为:除尘前后叶片光谱曲线在350～700,780～1 300,1 900～2 500nm波段区间内有较大差异,同时尘埃量与叶片单波段光谱反射率比值呈负相关,相关度最大值点为737波段,属于近红外波段,相关系数可达-0.8左右。在尘埃量与叶片光谱多波段组合关系研究中得到,948和945波段构成的NDVI指数与尘埃量的相关度最大,相关系数可达0.76。在叶片滞尘量反演研究中,对比传统意义滞尘量回归模型,引进的偏最小二乘算法(PLS)可使叶片滞尘量反演精度略有提高,最后由回归模型精度评定可得偏最小二乘法反演效果较传统回归好。

关键词：大叶黄杨高光谱尘埃量反演回归分析偏最小二乘法

Liquid Chromatographic Determination of Scopolamine in Hair with Suspended Drop Liquid Phase Microextraction Technique

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American Journal of Analytical Chemistry 2011年第2期2卷 235-242页

作者： Mahboubeh Masrournia Zarrin es’ haghi Mostafa Amini 不详

Hair analysis is used in some branches of alternative medicine as a method of investigation to assist diagnosis. It is very useful when a history of drug use is difficult or impossible to obtain. In this re-search suspended droplet liquid phase microextraction (SDLME) coupled with high-performance liquid chromatography and photodiode array detection (HPLC-DAD) was used for preconcentration and analysis of scopolamine in hair samples. Therefore scopolamine was extracted from 2.0 g hair sample incubated in methanol (5 h, 50°C) and adjusted to pH 7.4 with, na2HPO4–H3PO4 buffer solution (donor phase, P1) into an organic phase (P2) 350 μl n-octanol and then back extracted into a micro drop of aqueous acceptor phase (P3), adjusted at pH 3, with HCL. The extraction time, T1 (from P1 to P2) was 2 min and T2 (from P2 to P3) was 30 min. Optimum instrumental conditions were included;A C18 reverse phase column with water-acetonitrile-methanol (80:10:10) as the mobile phase was used and wavelength for UV detec-tion was 205 nm. The linear range was 10 to 10000 ng●mL–1, enrichment factor, detec-tion limit and relative standard deviation were 77, 0.1 ng●mL–1 and 5.4 respectively.

关键词： Column Liquid Chromatography Directly Suspended Droplet Liquid Phase Microextraction (SDLME) Scopolamine Hair Sample

Threshold for maximal electroshock seizures(MesT) at three developmental stages in young mice

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Zoological Research 2019年第3期40卷 231-235页

作者： Cheng Xiang Zhi-na Li Tian-Zhuang Huang Jing-Hui Li Lei Yang Jing-Kuan Wei Faculty of Life Science and Technology Kunming University of Science and Technology First Affiliated Hospital of Kunming Medical University Department of Neurosurgery Kunming Children's Hospital

Early brain development after birth is extremely dynamic,suggest!ng that potential functional changes occur during this *** this study,the maximal electroshock seizure threshold(MesT)was used to explore the electrophysiological variation among three developmental stages in young mice(no more than 5 weeks old).The induced electroshock seizure(es)behavior of early post natal mice(1-2-weeks old)differed from that during weaning(3 weeks old)and early puberty(4-5-weeks old).Thus,we further explored their respective characteristic responses to the es *** the stimulation current(SC)was limited to 4.0 mA,only the 1-2-week-old mice were induced to exhibit es behavior at voltages of 30 V and 40 V,indicating they were more sensitive to maximal electroshock seizure(Mes)(response to lower voltage).

关键词： maximal electroshock seizures young mice