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耕作模式对坡耕地土壤水分和大豆产量的影响

农业工程学报 2018年第22期34卷 128-137页

作者：邱野王瑄沈阳农业大学水利学院沈阳110161

为了探讨北方土石低山地区不同耕作模式对坡耕地的土壤水分特征及其对作物产量的影响,以10°坡耕地大豆田为研究对象,监测了传统耕作(CT)、免耕(ZT)、免耕秸秆覆盖(NT)和横垄(CR)4种不同处理下0～100cm土壤水分垂直变化和水平变化,测定... 详细信息

为了探讨北方土石低山地区不同耕作模式对坡耕地的土壤水分特征及其对作物产量的影响,以10°坡耕地大豆田为研究对象,监测了传统耕作(CT)、免耕(ZT)、免耕秸秆覆盖(NT)和横垄(CR)4种不同处理下0～100cm土壤水分垂直变化和水平变化,测定了大豆产量和水分利用效率。结果表明:1)在大豆不同生育期中,各处理在0～40cm土壤水分含量均表现为:NT>ZT>CR>CT,当土层深度大于40 cm时,各处理间土壤水分含量的大小关系发生波动变化,其中ZT和NT能明显改善0～50cm土层土壤水分含量,较CT处理保墒效果提高25.34%～35.57%。2)CT和ZT处理坡位间土壤水分含量的大小关系,受大豆生育期内总降雨量的影响较小,分别表现为:下坡位>中坡位>上坡位和下坡位≈中坡位>上坡位,而NT和CR处理坡位间土壤水分含量的大小关系,会随着大豆生育期内降雨总量的不同而产生微变。3)各处理剖面土壤水分空间分布格局均表现出下湿上干的特点,CT和CR湿润土层(体积含水率≥11.6%)分别位于坡底40～100 cm和坡顶40～100 cm处,而干燥土层(体积含水率≤8.6%)则分别位于坡顶10～30 cm和坡底10～20 cm处。ZT湿润土层(体积含水率≥12%)分布集中性较差,NT湿润土层分布集中性最好,且范围最大,占据了整个坡面40～100cm深度范围。4)所考虑的3个因素对土壤水分含量影响作用的大小表现为:耕作模式>剖面深度>坡位。5)在2a试验中,与CT相比CR、ZT和NT处理产量分别平均增加8.77%、15.68%和26.74%,水分利用效率分别平均提高6.32%、11.6%和20.61%,因此建议在研究区种植大豆时,优先采用NT耕作模式。

关键词：土壤水分作物耕作大豆产量水分利用效率

microstructure and mechanical properties of Fe-doped NiAl-28Cr-6mo eutectic alloys

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Transactions of Nonferrous metals Society of China 2016年第4期26卷 1025-1031页

作者： A.GUNGOR h.DEmIRTAS metallurgical and materials Engineering Department Engineering Faculty Karabuk UniversityKarabuk 78050Turkey

Room temperature and high temperature microstructural and mechanical properties of arc melted Ni Al-28Cr-6mo eutectic alloys doped with 0.1% Fe, 0.2% Fe and 0.5% Fe(mole fraction) were investigated. The homogenization heat treatment of the alloys was conducted at 1300℃ in Ar atmosphere. microscopic analyses, hardness measurements, XRD measurements and compression tests were used to characterize the alloys. As-cast and homogenized alloys exhibit fine cellular eutectic structures with coarse intercellular eutectic structure. The increase in the content of Fe results in coarsening eutectic layers and the decrease in eutectic cells. All alloys have very high compressive stress and strain at room temperature. The addition of Fe has small negative impact on the strength and ductility of the alloys at room temperature. however, the addition of Fe increases the high temperature strength of the alloy. high temperature XRD patterns show that peaks shift to lower Bragg angles. This indicates that the lattice parameter of the alloys increases.

关键词： aluminium alloy microalloying solid-solution hardening brittleness ductility microstructure mechanical properties

Applicability and efficacy of a model for prevention of perinatal transmission of hepatitis B virus infection:Single center study in Egypt

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World Journal of Gastroenterology 2014年第45期20卷 17075-17083页

作者： hanaa m El-Karaksy Lamiaa m mohsen Doa'a A Saleh mona S hamdy Noha A Yassin mohamed Farouk mohamed E Salit mortada h El-Shabrawi Department of Pediatrics Kasr Al-Ainy School of Medicine Cairo University Department of Community medicine Kasr AlAiny School of Medicine Cairo University Department of Clinical and Chemical Pathology Kasr Al-Ainy School of Medicine Cairo University Department of Obstetrics and Gynecology Kasr Al-Ainy School of Medicine Cairo University

AIm: To identify possible maternal risk factors for hepatitis B virus (hBV) acquisition and assess the efficacy of immunoprophylaxis given to infants born to hepatitis B virus surface antigen (hBsAg) positive mothers.

关键词： Egypt hepatitis B virus hepatitis B virus surface antigen positive mothers Immunoprophylaxis Perinatal transmission

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高速铁路挡风墙高度和距离优化分析

西南交通大学学报 2014年第2期49卷 240-246页

作者：叶坤李人宪西南交通大学机械工程学院四川成都610031 中国空气动力研究与发展中心四川绵阳622000

为探讨挡风墙对列车横向气动性能的影响，基于可压缩粘性流体Navier-Stokes方程和k-ε两方程湍流模型，采用有限体积法，计算了列车在直线和不同半径曲线线路上运行时，不同挡风墙高度和距离的275种工况下列车侧向力和侧翻力矩，获得了... 详细信息

为探讨挡风墙对列车横向气动性能的影响，基于可压缩粘性流体Navier-Stokes方程和k-ε两方程湍流模型，采用有限体积法，计算了列车在直线和不同半径曲线线路上运行时，不同挡风墙高度和距离的275种工况下列车侧向力和侧翻力矩，获得了最佳挡风墙高度和距离．研究结果表明：在列车速度为200～400 km/h，风速为20～40 m/s的条件下，列车在直线线路上运行的最佳挡风墙高度和距离分别约为1．90和3．90 m；当弯道半径为1000～7000 m时，曲线线路最佳挡风墙高度随弯道半径增大线性减小，最佳挡风墙距离与弯道半径关系不大，约4．50 m；风速和列车速度对挡风墙的最佳高度和最优距离影响很小；如果挡风墙高度过低或距离过近，头车和尾车所受侧向力和侧翻力矩方向不同．

关键词：高速铁路挡风墙最佳高度和距离数值分析有限体积法

highly Sensitive mid-Infrared Photodetector Enabled by Plasmonic hot Carriers in the First Atmospheric Window

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Chinese Physics Letters 2022年第5期39卷 108-112页

作者： Yuan-Fang Yu ye Zhang Fan Zhong Lin Bai hui Liu Jun-Peng Lu Zhen-hua Ni School of Physics Southeast UniversityNanjing 211189China National Laboratory of Solid State microstructures&School of Physics Collaborative Innovation Center of Advanced MicrostructuresNanjing UniversityNanjing 210093China

The first atmospheric window of 3-5μm in the mid-infrared(mIR)spectral range pertains to crucial application fields,with particular scientific and technological ***,conventional narrow-bandgap semiconductors operating at this band,represented by mercury cadmium telluride and indium antimonide,suffer from limited specific detectivity at room temperature and hindered optoelectronic *** this study,a plasmonic hot electron-empowered mIR photodetector based on Al-doped ZnO(AZO)/bi-layer graphene heterostructure is *** electrons oscillate coherently in AZO disk arrays,resulting in strong localized surface plasmon resonance(LSPR)in the mIR *** photoelectric conversion efficiency at 3-5μm is significantly improved due to plasmon-induced hot-electron extraction and LSPR-enhanced light *** specific detectivity reaches about 1.4×10^(11)Jones and responsivity is up to 4712.3 A/W at wavelength of 3μm at room *** device’s specific detectivity is among the highest performance of commercial state-ofthe-art photodetectors and superior to most of the other 2 D materials based photo detectors in the mIR *** results demonstrate that a plasmonic heavily doped metal oxides/2 D material heterostructure is a suitable architecture for constructing highly sensitive room-temperature mIR photodetectors.

关键词： Infrared highly narrow

Procalcitonin,and cytokines document a dynamic inflammatory state in non-infected cirrhotic patients with ascites

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World Journal of Gastroenterology 2014年第9期20卷 2374-2382页

作者： Bashar m Attar Christopher m moore magdalena George Nicolae Ion-Nedelcu Rafael Turbay Annamma Zachariah Guiliano Ramadori Jawed Fareed David h Van Thiel Division of Gastroenterology and hepatology John H Stroger Hospital of Cook County Chicago IL 60612 United States David h Van Thiel Division of Gastroenterology and HepatologyRush University Medical Center Chicago IL 60612 United States Division of Gastroenterology and hepatology Victor Babes Infectious Clinic 050094 Bucharest Romania Division of Gastroenterology and hepatology August Georg University D-37075 Gottingen Germany Division of Gastroenterology and hepatology Loyola University Medical Center Maywood IL 60153 United States

AIm: To quantitate the simultaneous serum and ascitic fluid levels of procalcitonin and inflammatory markers in cirrhotics with and without ascites.

关键词： Ascites Bacterial translocation Inflammatory markers Procalcitonin Cirrhosis

Effects of Zr substitution on soot combustion over cubic fluorite-structured nanoceria:Soot-ceria contact and interfacial oxygen evolution

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Journal of Environmental Sciences 2021年第3期33卷 293-303页

作者： Peng Liu Xiaoliang Liang Yanliu Dang Junkai he Alireza Shirazi-Amin Laura A.Achola Shanka Dissanayake hanlin Chen mingli Fu Daiqi ye Steven L.Suib School of Environment and Energy South China University of TechnologyGuangzhou 510006China CAS Key Laboratory of mineralogy and metallogeny/Guangdong Provincial Key Laboratory of mineral Physics and materials Guangzhou Institute of GeochemistryChinese Academy of SciencesGuangzhou 510640China Institute of materials Science University of ConnecticutStorrsConnecticut 06269USA Department of Chemistry University of ConnecticutStorrsConnecticut 06269USA Guangdong Provincial Key Laboratory of Petrochemical Pollution Processes and Control School of Environmental Science and EngineeringGuangdong University of Petrochemical TechnologyMaoming 525000China University of Chinese Academy of Sciences Beijing 100049China

Ceria is widely used as a catalyst for soot combustion,but effects of Zr substitution on the reaction mechanism is *** present work elucidates effects of Zr substitution on soot combustion over cubic fluorite-structured *** nanostructured CeO_(2),Ce_(0.92)Zr_(0.08)O_(2),and Ce_(0.84)Zr_(0.16)O_(2)composed of 5-6 nm crystallites display T_(m-CO2)(the temperature at maximum CO_2 yield)at 383,355,and 375℃under 10 vol.%O_(2)/N_(2),*** size of agglomerate decreases from 165.5 to 51.9-57.3 nm,which is beneficial for the sootceria ***,Zr increases the amount of surface oxygen vacancies,generating more active oxygen(O_(2)^-and O^(-))for soot ***,the activities of Ce_(0.92)Zr_(0.08)O_(2)and Ce_(0.84)Zr_(0.16)O_(2)in soot combustion are better than that of CeO_(2).Although oxygen vacancies promote the migration of lattice O~(2-),the enriched surface Zr also inhibits the mobility of lattice O^(2-).Therefore,the T_(m-CO2)of Ce_(0.84)Zr_(0.1)6 O_(2)is higher than that of Ce_(0.92)Zr_(0.08)O_(2).Based on reaction kinetic study,soot in direct contact with ceria preferentially decomposes with low activation energy,while the oxidation of isolated soot occurs through diffusion with high activation *** obtained findings provide new understanding on the soot combustion over nanoceria.

关键词： Nanoceria Soot combustion Zr substitution Oxygen mobility Reaction kinetic

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基于Em算法的对传网络学习及应用

计算机研究与发展 2006年第5期43卷 856-861页

作者：郝玉叶世伟中国科学院研究生院北京100049 中国科学院研究生院信息科学与工程学院北京100049

为克服“胜者全得”对传网络的缺陷,提出使用基于软竞争机制的对传网络.这样增加了网络的训练复杂度.为此,把竞争层中隐单元的输出作为未观察到的缺省随机变量,使用Em算法对基于软竞争的对传网络进行训练,降低训练复杂度,加快网络的收... 详细信息

为克服“胜者全得”对传网络的缺陷,提出使用基于软竞争机制的对传网络.这样增加了网络的训练复杂度.为此,把竞争层中隐单元的输出作为未观察到的缺省随机变量,使用Em算法对基于软竞争的对传网络进行训练,降低训练复杂度,加快网络的收敛速度.在实现Em算法的m步时,根据基于软竞争机制对传网络竞争层的特点,对Em算法实现进行改进,没有使用常用的迭代重新加权最小二乘算法,而利用样本加权平均求取隐层单元的权值向量,使Em算法更加简单易行,收敛速度快.仿真实验结果表明,基于软竞争机制的对传网络具有很好的泛化性能,特别在模式分类上具有很好的实际应用价值.

关键词：对传网络软竞争最大似然估计

SImAP500: A novel risk score to identify recipients at higher risk of hepatocellular carcinoma recurrence following liver transplantation

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World Journal of Transplantation 2024年第3期14卷 132-143页

作者： Amr Alnagar Nekisa Zakeri Konstantinos Koilias Rosemary E Faulkes Rachel Brown Owen Cain m Thamara P R Perera Keith J Roberts Rebeca Sanabria-mateos David C Bartlett Yuk Ting ma Shivan Sivakumar Shishir Shetty Tahir Shah Bobby V m Dasari Department of hBP and Liver Transplantation Surgery Queen Elizabeth HospitalUniversity Hospitals BirminghamBirmingham B152GWUnited Kingdom Centre for Liver Research Institute of Biomedical ResearchBirmingham B152TTUnited Kingdom Department of hepatology Queen Elizabeth HospitalUniversity Hospitals BirminghamBirmingham B152GWUnited Kingdom Department of Pathology University Hospitals Birmingham NHS Foundation TrustBirmingham B152GWUnited Kingdom Department of Oncology Queen Elizabeth HospitalUniversity Hospitals of BirminghamBirmingham B152GWUnited Kingdom

BACKGROUND Recurrence of hepatocellular carcinoma(hCC)following liver transplantation(LT)has a devastating influence on recipients’survival;however,the risk of recur-rence is not routinely *** stratification is vital with a long LT waiting time,as that could influence the recurrence despite strict listing *** This study aims to identify predictors of recurrence and develop a novel risk pre-diction score to forecast hCC recurrence following *** A retrospective review of LT for hCC recipients at University hospitals Bir-mingham between July 2011 and February *** and multivariate analyses were performed to identify recurrence predictors,based on which the novel SImAP500(satellite nodules,increase in size,microvascular invasion,AFP>500,poor differentiation)risk score was *** 234 LTs for hCC were performed with a median follow-up of 5.3 *** developed in 25 patients(10.7%).On univariate analyses,RETREAT score>3,α-fetoprotein(AFP)at listing 100-500 and>500,bridging,increased tumour size between imaging at the listing time and explant histology,increase in the size of viable tumour between listing and explant,presence of satellite nodules,micro-and macrovascular invasion on explant and poor differentiation of tumours were significantly associated with recurrence,based on which,the SImAP500 risk score is *** SImAP500 demonstrated an excellent predictive ability(c-index=0.803)and outper-formed the RETREAT score(c-index=0.73).SImAP500 is indicative of the time to disease *** SImAP500 risk score identifies the LT recipients at risk of hCC *** stratification allows patient-centric post-transplant surveillance *** validation of the score is recommended.

关键词： Liver transplantation hepatocellular carcinoma Recurrence Survival