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A large congenital and solitary intrahepatic arterioportal fistula in an old woman

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World Journal of Gastroenterology 2009年第13期15卷 1656-1659页

作者： zhen-Ya Lu Jian-yang Ao Tian-An Jiang Zhi-Yi Peng Zhan-kun Wang Department of InternalMedicine First Affiliated Hospital Medical College ZhejiangUniversity Hangzhou 310003 Zhejiang Province China Department of Ultrasound First Affiliated Hospital Medical College Zhejiang UniversityHangzhou 310003 Zhejiang Province China Department of Radiology First Affiliated HospitalMedical College Zhejiang University Hangzhou 310003Zhejiang Province China

Arterioportal fistula(APF)is a rare cause of portal hypertension and may lead to *** can be congenital,post-traumatic,iatrogenic(transhepatic intervention or biopsy)or related to ruptured hepatic artery *** APF is a rare condition even in *** this case report,we describe a 73-year-old woman diagnosed as APF by ultrasonography,computed tomography,and hepatic artery selective *** fistula was embolized twice but failed,and she still suffered from alimentary tract ***,selective arteriography of the hepatic artery was performed again and venae coronaria ventriculi and short gastric vein were *** the 2-year follow-up,the patient remained *** therefore argue that embolization of venae coronaria ventriculi and short gastric vein may be an effective treatment modality for intrahepatic APF with severe upper gastrointestinal bleeding.

关键词： Congenital intrahepatic arterioportal fistula Liver Embolization Portal hypertension Angiography

Effect of Electric Field on the Electron-Surface Optical Phonon Scattering Rates in Quantum Wires

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Chinese Physics Letters 1996年第4期13卷 297-300页

作者： CHANG Kai WANG Ruo-zhen MA Ben-kun Department of Physics Beijing Normal UniversityBeijing 100875

By using the variational method and the dielectric continuum model,we investigate the effect of electric Held on the intrasubband scattering rates of electron-surface optical *** results show that the scattering rates tend to increase with the electric field *** scattering rates become significant for wide quantum well wire and sufficiently high fields.

关键词： strength. Electron variational

Enhanced electrode kinetics and electrochemical properties of low-cost NaFe_(2)PO_(4)(SO_(4))_(2)via Ca~(2+)doping as cathode material for sodium-ion batteries

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Journal of Materials Science & Technology 2021年第19期78卷 176-182页

作者： Shao-Fang Li zhen-Yi Gu Jin-Zhi Guo Xian-kun Hou Xu yang Bo Zhao Xing-Long Wu National fy Local United Engineering Laboratory for Power Batteries Faculty of ChemistryNortheast Normal UniversityChangchun130024China Key Laboratory for UV Light-Emitting Materials and Technology Northeast Normal UniversityMinistry of EducationChangchun130024China

In recent years,sodium-ion batteries(SIBs)have been considered as one of the most promising alternatives to lithium-ion batteries(LIBs).Here,a new Na-super-ionic conductor(NASICON)cathode material Na Fe_(2)PO_(4)(SO_(4))_(2)is successfully prepared through solid state method for *** the poor electronic conductivity of iron-based materials results in its poor rate and cycle *** the electrochemical is effectively promoting via Ca^(2+)***_(0.84)Ca_(0.08)Fe_(2)PO_(4)(SO_(4))_(2)have achieved considerable electrochemical *** first discharge specific capacity is 121.6 m A h g^(-1)at 25 m A g^(-1)with the voltage platform(-3.1 V)corresponding to Fe^(2+/3+).After 100 cycles,the capacity retention is 55.1%.The excellent electrochemical performance is caused by some Na^(+)is substituted by Ca^(2+)and leading to the fast sodium kinetics,which is well proved by the powder X-ray diffraction pattern and well corresponding to the galvanostatic intermittent titration technique and cyclic voltammetry testing result(the diffusivity values are around at 10^(-12)cm^(2)s^(-1)).

关键词： NaFe_(2)PO_(4)(SO_(4))_(2) Na-super-ionic conductor Sodium-ion batteries Cathode Ca~(2+)doping

Chemically synthesizing exchange-coupled SmCo_(5)/Sm_(2)Co_(17) nanocomposites

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Rare Metals 2021年第3期40卷 575-581页

作者： Yao-Hui Xu Qiang Jiang kun Li zhen-Hui Ma School of Physics and Electronic Engineering Laboratory for Functional MaterialsLeshan Normal UniversityNanjing 211189China Jiangsu Key Laboratory for Design and Manufacture of Micro-Nano Biomedical Instruments School of Mechanical EngineeringSoutheast UniversityNanjing 211189China College of Materials Science and Engineering Key Laboratory of Advanced Functional MaterialsMinistry of Education of ChinaBeijing University of TechnologyBeijing 100124China Department of Chemistry Brown UniversityProvidenceRI 02912USA

A new strategy to chemically synthesize exchange-coupled SmCo_(5)/Sm_(2) Co_(17) nanocomposites by in situ decomposition of SmCox(5 详细信息

A new strategy to chemically synthesize exchange-coupled SmCo_(5)/Sm_(2) Co_(17) nanocomposites by in situ decomposition of SmCox(5

关键词： SmCo_(5) Nanocomposites Exchange coupling Coercivity

Ca_(2)MnO_(4)-layered perovskite modified by NaNO_(3)for chemical-looping oxidative dehydrogenation of ethane to ethylene

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Chinese Journal of Chemical Engineering 2024年第4期68卷 53-64页

作者： Weixiao Ding kun Zhao Shican Jiang zhen Huang Fang He College of Chemistry and Bioengineering Guilin University of TechnologyGuilin 541006China Guangzhou Institute of Energy Conversion Chinese Academy of SciencesGuangzhou 510640China School of Chemistry and Chemical Engineering Nanjing University of Science and TechnologyNanjing 210094China

Chemical-looping oxidative dehydrogenation(CL-ODH)is a process designed for the conversion of alkanes into olefins through cyclic redox reactions,eliminating the need for gaseous O_(2).In this work,we investigated the use of Ca_(2)MnO_(4)-layered perovskites modified with NaNO_(3) dopants,serving as redox catalysts(also known as oxygen carriers),for the CL-ODH of ethane within a temperature range of 700-780℃.Our findings revealed that the incorporation of NaNO_(3) as a modifier significantly-nhanced the selectivity for-thylene generation from Ca_(2)MnO_(4).At 750℃and a gas hourly space velocity of 1300 h^(-1),we achieved an-thane conversion up to 68.17%,accompanied by a corresponding-thylene yield of 57.39%.X-ray photoelectron spectroscopy analysis unveiled that the doping NaNO_(3) onto Ca_(2)MnO_(4) not only played a role in reducing the oxidation state of Mn ions but also increased the lattice oxygen content of the redox ***,formation of NaNO_(3) shell on the surface of Ca_(2)MnO_(4) led to a reduction in the concentration of manganese sites and modulated the oxygen-releasing behavior in a step-wise *** modulation contributed significantly to the enhanced selectivity for ethylene of the NaNO_(3)-doped Ca_(2)MnO_(4) *** findings provide compelling evidence for the potential of Ca_(2)MnO_(4)-layered perovskites as promising redox catalysts in the context of CL-ODH reactions.

关键词： Chemical-looping oxidative dehydrogenation Ethane Ethylene NaNO_(3)-doped Ca_(2)MnO_(4)redox catalyst Layered perovskites

HNCO hydrolysis performance in urea-water solution thermohydrolysis process with and without catalysts

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2010年第11期11卷 849-856页

作者： zhen-chao CHEN Wei-juan yang Jun-hu ZHOU Hong-kun LV Jian-zhong LIU Ke-fa CEN State Key Laboratory of Clean Energy Utilization Zhejiang University Hangzhou 310027 China

The thermolysis of urea-water solution and its product, HNCO hydrolysis is investigated in a dual-reactor system. For the thermal decomposition below about 1073 K, the main products are ammonia (NH3) and isocyanic acid (HNCO) whereas at higher temperatures the oxidation processes take effect and the products include a low concentration of nitric oxide (NO) and nitrous oxide (N2O). The gas HNCO is quite stable and a high yield of HNCO is observed. The ratio of NH3 to HNCO increases from approximately 1.2 to 1.7 with the temperature. The chemical analysis shows that H radical is in favor of HNCO hydrolysis by instigating the reaction HNCO+H·→·NH2+CO and high temperature has positive effect on H radical. The hydrolysis of HNCO over an alumina catalyst made using a sol-gel process (designated as γ-Al2O3) is investigated. The conversion of HNCO is high even at the high space velocities (6×105 h-1) and low temperatures (393–673 K) in the tests with catalysts, which enhances HNCO hydrolysis and raises the ratio of NH3 to HNCO to approximately 100. The pure γ-Al2O3 shows a better catalytic performance than CuO/γ-Al2O3. The addition of CuO not only reduces the surface area but also decreases the Lewis acid sites which are recognized to have a positive effect on the catalytic activity. The apparent activation energy of the hydrolysis reaction amounts to about 25 kJ/mol in 393–473 K while 13 kJ/mol over 473 K. The overall hydrolysis reaction rate on catalysts is mainly determined by external and internal mass-transfer limitations.

关键词： Urea-water solution Sol-gel method γ-Al2O3 HNCO hydrolysis

Comparative analysis of cytochrome P450-like genes from Locusta migratoria manilensis： expression profiling and response to insecticide exposure

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Insect Science 2012年第1期19卷 75-85页

作者： Yan-Qiong Guo Jian-zhen Zhang Mei-Ling yang Liang-zhen Yan kun Yan Zhu Ya-Ping Guo En-Bo Ma Institute of Appfied Biology Shanxi UniversityTaiyuan College of Agriculture Shanxi Agricultural UniversityTaiguShanxi ProvinceChina Department of Entomology Kansas State UniversityManhattanKansasUSA

The cytochrome P450 monooxygenase （cytochrome P450） gene superfamily comprises many genes that may be involved in the biotransformations of pesticides and other xenobiotics. To date, very little is known about cytochrome P450 genes in the oriental migratory locust, Locusta migratoria manilensis. In this study, we carried out a genomewide analysis ofcytochrome P450 genes of the locust to identify putative cytochrome P450 genes and characterize their expression responses to insecticide exposures. We identified 15 cytochrome P450-1ike genes from a locust expressed sequence tag database （LocustDB）. Reverse transcription polymerase chain reaction （RT-PCR） analysis showed that most cytochrome P450-1ike genes displayed different tissue and developmental stage expression patterns. However, most of them were predominantly expressed in the midgnt, gastric caeca, fatbodies, and/or hindgut. Biochemical analysis showed that cytochrome P450 was differentially affected by three different insecticides. Deltamethrin caused significant inductions in 12 h at LD30 （dose to kill 30% of the tested individuals） in the nymphs, whereas malathion and carbaryl did not have significant effect on cytochrome P450 enzyme activity. Further RT-PCR analysis Showed significant increases of transcriptions of several cytochrome P450 genes in deltamethrin-treated locusts. Thus, the increased cytochrome P450 enzyme activity is likely due to increased transcriptions of multiple cytochrome P450 genes in response to deltamethrin exposure. These results are expected to help us better understand the interactions between insecticides and major detoxification enzymes, and possible changes of the susceptibility to other insecticides in deltamethrin-treated insects at various molecular levels.

关键词： cytochrome P450 monooxygenase deltamethrin gene expression profiling insecticide Locusta migratoria manilensis

Effects of gate-buffer combined with a p-type spacer structure on silicon carbide metal semiconductor field-effect transistors

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Chinese Physics B 2012年第1期21卷 426-432页

作者： Song kun Chai Chang-Chun yang Yin-Tang Chen Bin Zhang Xian-Jun Ma zhen-yang Key Laboratory of Wide Band-Gap Semiconductor Materials and Devices of Ministry of Education School of MicroelectronicsXidian UniversityXi'an 710071China

An improved structure of silicon carbide metal-semiconductor field-effect transistors （MESFET） is proposed for high power microwave applications. Numerical models for the physical and electrical mechanisms of the device are presented, and the static and dynamic electrical performances are analysed. By comparison with the conventional structure, the proposed structure exhibits a superior frequency response while possessing better DC characteristics. A p-type spacer layer, inserted between the oxide and the channel, is shown to suppress the surface trap effect and improve the distribution of the electric field at the gate edge. Meanwhile, a lightly doped n-type buffer layer under the gate reduces depletion in the channel, resulting in an increase in the output current and a reduction in the gate-capacitance. The structural parameter dependences of the device performance are discussed, and an optimized design is obtained. The results show that the maximum saturation current density of 325 mA/mm is yielded, compared with 182 mA/mm for conventional MESFETs under the condition that the breakdown voltage of the proposed MESFET is larger than that of the conventional MESFET, leading to an increase of 79% in the output power density. In addition, improvements of 27% cut-off frequency and 28% maximum oscillation frequency are achieved compared with a conventional MESFET, respectively.

关键词： silicon carbide metal-semiconductor field-effect transistor p-type spacer gate-buffer

Investigation on strong nonlinear interactions between underwater explosion and water surface based on compressible multiphase flow with phase transition

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Journal of Hydrodynamics 2023年第2期35卷 351-364页

作者： Jun Yu Hai-kun Wang zhen-xin Sheng Yi Hao China Ship Scientific Research Center Wuxi214082China Taihu Laboratory of Deep-sea Technological Science Wuxi214082China

The strong nonlinear interactions between underwater explosion and water surface were numerically investigated using a phase transition model based on a four-equation system,which can deal with the complex deformable interface among different phases,including water,air,explosion bubble,and *** numerical method is verified by comparing the numerical results with experimental results,and good agreements are *** study considers an ideal sine wave for simulating the shape of water *** examples of different detonation depths of charge are *** each example,the first case is the basic simulation without surface wave,and the other three cases are the simulations with sine waves of different *** characteristics of the interactions,such as shock wave propagation,explosion bubble expansion,and the generation,development,and collapse of cavitation,are observed in the numerical *** capturing the detailed density and pressure contours during the interaction process,we can better understand the underlying mechanisms of the explosion bubble,cavitation,and surface *** numerical results demonstrate that geometric nonlinearity impacts cavitation evolution and the explosion bubble movement ***,the secondary cavitation phenomenon has been found in the cases without surface wave,and its fundamental physical mechanism is presented in *** present results can expand the existing database of multiphase flow in the underwater explosion and provide an insight into the strong nonlinear interaction between the underwater explosion and water surface.

关键词： Underwater explosion compressible multiphase flow phase transition model cavitation water surface