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World Journal of Gastroenterology 2004年第15期10卷 2281-2283页

作者： Gabrio Bassotti Fabio Chistolini Francis Sietchiping-Nzepa Giuseppe de Roberto Antonio Morelli Gastrointestinal and Hepatology Section Department of Clinical and Experimental MedicineUniversity of PerugiaItaly

AIM: To report our experience with empiric antimicrobial monotherapy (piperacillin/tazobactam, of which no data are available in such specific circumstances) in microbiologically-documented infections in patients with benign and malignant conditions of the biliary ***: Twenty-three patients, 10 with benign and 13 with malignant conditions affecting the biliary tree and microbiologically-documented infections were recruited and the efficacy of empirical antibiotic therapy was ***: The two groups featured similar demographic and clinical data. Overall, the infective episodes were most due to Gram negative agents, more than 60% of such episodes (mostly in malignant conditions) were preceded by invasive instrumental maneuvers. Empirical antibiotic therapy with a single agent (piperacillin/tazobactam) was effective in more than 80% of cases. No deaths were reported following infections. CONCLUSION: An empiric therapeutic approach with piperacillin/tazobactam is highly effective in biliary tract infections due to benign or malignant conditions.

关键词： Adult Aged Aged, 80 and over Anti-Bacterial Agents Biliary Tract Diseases Biliary Tract Neoplasms Drug Combinations Empirical Research Female Humans Infection Male Middle Aged Penicillanic Acid derivatives Piperacillin

Study on the Interaction between CdSe Quantum Dots and Bovine Serum Albumin with Ultraviolet Visible Absorption Spectroscopy

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Chinese Chemical Letters 2006年第7期17卷 961-964页

作者： He You HAN de Hong HU Jian Gong LIANG Zong Hai SHENG College of Science MOA Key Laboratory of Food Safety Evaluation Huazhong Agricultural University Wuhan 430070

The interaction of CdSe quantum dots （QDs） with bovine serum albumin （BSA） has been investigated with ultraviolet visible absorption spectroscopy （UVAS）. It was found that the absorption intensity of CdSe QDs significantly decreased after adding BSA solution, showing that CdSe QDs were bonded to BSA. The binding molar ratio was 1：1 and the binding constant was 9.7 × 10^6 L mol^-1.

关键词： CdSe quantum dots bovine serum albumin interaction.

Mechanism of Ascorbic Acid-induced Reversion Against Malignant Phenotype in Human Gastric Cancer Cells

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Biomedical and Environmental Sciences 2006年第5期19卷 385-391页

作者： YA-XUAN SUN QIU-SHENG ZHENC GANG LI de-AN GUO ZI-REN WANG Life Sciences School of Lanzhou University Lanzhou 730000 Gansu China Key Laboratory of Xinjiang Endemic Phytomedicine Resources Ministry of Education Shihezi 832002 Xinjiang China The State Key Laboratory of Natural and Biomimetic Drugs School of Pharmaceutical Sciences Peking University Beijing 100083 China

Objective To find out the mechanisms of redifferentiation and reversion of malignant human gastric cancer cells induced by ascorbic acid. Methods Human gastric cancer cells grown in the laboratory were used. The Trypan blue dye exclusion method was used to determine the cell doubling time. The electrophoresis rate and colonogenic potential were the indices used to measure the rate of redifferentiation. The content of malondialdehyde （MDA） was measured using the thiobarbituric acid （TBA） method. The activities of superoxide dismutase （SOD）, catalase （CAT） and the content of H2O2 were evaluated by spectrophotography. Results Six mmol/L ascorbic acid was used as a positive control. Human gastric cancer cells were treated with 75 μm hydrogen peroxide, which alleviated many of the malignant characteristics. For example, the cell surface charge obviously decreased and the electrophoresis rate dropped from 2.21 to 1.10 pm·s^-1·cm^-1 The colonogenic potential, a measure of cell differentiation, decreased 90.2%. After treatment with ascorbic acid, there was a concentration- and time-dependent increase in hydrogen peroxide （H2O2） and the activity of superoxide dismutase （SOD）. However, the activity of catalase （CAT） resulted in a concentration- and time-dependent decrease. SOD and 3-amino- 1,2,4-triazole （AT） exhibited some effects, but there were statistically significant differences between the SOD and AT group and the H2O2 group, Conclusions Ascurbic acid induces growth inhibition and redifferentiation of human gastric cancer cells through the production of hydrogen peroxide.

关键词： Aminotriazole Ascorbic acid Catalase Gastric cancer Hydrogen peroxide Redifferentiation Superoxide dismutase

Recovering information in probabilistic quantum teleportation

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Frontiers of physics 2019年第6期14卷 9-13页

作者： Luis Roa Andrea Espinoza Ariana Munoz Maria L·Ladron de Guevara departamento de Física Universidad de ConcepciónCasilla 160-CConcepciónChile departamento de Física Universidad Católica del NorteAngamos 0610AntofagastaChile Facultad de Ingeniería Universidad Autónoma de Chile5 Poniente 1670TalcaChile

In this paper we redesign the probabilistic teleportation scheme considered in ***.A 61,034301(2000)by Wan-Li Li et al.,where the optimal state extraction protocol complements the basic teleportation process with a partially entangled pure state channel,in order to transfer the unknown state with fidelity *** that scheme,where the information of the unknown state is lost if the state extraction fails,our proposal teleports exactly and optimally an unknown state,and allows to recover faithfully that state when the process has not *** order to study the resilience of the scheme,we apply it to the teleportation problem through a quantum channel in a mixed state with pure *** find that a successful process transfers an unfaithful state,namely,the outcome state acquires the decoherence of the channel,but the unknown state is recovered by the sender with fidelity 1 if the teleportation *** addition,in this case,the fidelity of the teleported state has quantum features only if the channel has an amount of entanglement different from zero.

关键词： quantum information teleportation

denitrification performance and sulfur resistance mechanism of Sm-Mn catalyst for low temperature NH_(3)-SCR

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Frontiers of Chemical Science and Engineering 2023年第5期17卷 617-633页

作者： Junlin Xie Yanli Ye Qinglei Li Tianhong Kang Sensheng Hou Qiqi Jin Feng He de Fang State Key Laboratory of Silicate Materials for Architectures Wuhan University of TechnologyWuhan 430070China Center for Materials Research and Analysis Wuhan University of TechnologyWuhan 430070China School of Materials Science and Engineering Wuhan University of TechnologyWuhan 430070China

MnO_(x)and Sm–Mn catalysts were prepared with the coprecipitation method,and they showed excellent activities and sulfur resistances for the selective catalytic reduction of NO_(x)by NH_(3)between 50 and 300℃in the presence of excess oxygen.0.10Sm–Mn catalyst indicated better catalytic activity and sulfur ***,the Sm doping led to multi-aspect impacts on the phases,morphology structures,gas adsorption,reactions process,and specific surface ***,it significantly enhances the NO conversion,N_(2)selectivity,and sulfur *** on various experimental characterization results,the reaction mechanism of catalysts and the effect of SO_(2)on the reaction process about the catalysts were extensively *** 0.10Sm–Mn catalyst,manganese sulfate and sulfur ammonium cannot be generated broadly under the influence of SO_(2)and the amount of surface adsorbed *** Bronsted acid sites strengthen significantly due to the addition of SO_(2),enhancing the sulfur resistance of the 0.10Sm–Mn catalyst.

关键词： MnO_(x) Sm–Mn catalyst NH_(3)-SCR sulfur resistance

Erosion-corrosion resistance of Mo-Ti- and Ni-Cr-Mo-alloyed medium-carbon martensitic steels: a critical analysis of synergistic effect of erosion and corrosion

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Journal of Iron and Steel Research International 2022年第8期29卷 1299-1311页

作者： de-fa Li Hang-yu Dong Cheng-yang Hu Kai-ming Wu Serhii Yershov Oleg Isayev School of Mechanical and Vehicle Engineering West Anhui UniversityLuan 237012AnhuiChina The State Key Laboratory of Refractories and Metallurgy Hubei Province Key Laboratory of Systems Science on Metallurgical ProcessingInternational Research Institute for Steel TechnologyWuhan University of Science and TechnologyWuhan 430081HubeiChina Laboratory for Excellence in Advanced Steel Research Materials Science and Engineering ProgramDepartment of MetallurgicalMaterials and Biomedical EngineeringUniversity of Texas at El PasoEl PasoTX 79968USA

Grain refinement renders Mo-Ti-alloyed medium-carbon martensitic steel to exhibit high hardness,high strength,and good toughness,but the erosion-corrosion resistance of steel in a corrosive slurry environment is not ***-Ti-alloyed medium-carbon martensitic steel is compared with Ni-Cr-Mo-alloyed medium-carbon martensitic steel,and the erosion-corrosion resistance of those two steels under impingement by NaCl solution with gravels has been *** components,pure-corrosion rate,pure-erosion rate,and synergistic effect of erosion and corrosion(SEEC)of erosion-corrosion rate,were *** pure-corrosion and pure-erosion rates of Mo-Ti-alloyed steel were higher than those of Ni-Cr-Mo-alloyed one;however,its erosion-corrosion rate was relatively lower because of a weak *** plastic deformation and work hardening due to gravel impingement were the essential reason for SEEC,which could be reduced by grain refinement,and consequently,Mo-Ti-alloyed steel with finer grains had better erosion-corrosion *** refinement could be an effective way to improve the erosion-corrosion resistance of martensitic steels.

关键词： Grain refinement Mo-Ti alloying Ni-Cr-Mo alloying Martensite Erosion-corrosion

New Form of Kerr-Newman Solution and Its Hawking Radiation via Tunneling

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Communications in Theoretical Physics 2006年第6X期46卷 1001-1004页

作者： JIANG Qing-Quan WU Shuang-Qing YANG Shu-Zheng CHEN de-You department of Physics Central China Normal University Wuhan 430079 China Institute of Theoretical Physics China West Normal University Nanchong 637002 China

Parikh-Wilzcek＇s recent work, which treats the Hawking radiation as semi-classical tunneling process from the event horizon of static Schwarzshild and Reissner-Nordstroem black holes, indicates that the factually radiant spectrum deviates from the precisely thermal spectrum after taking the self-gravitation interaction into account. In this paper, we extend Parikh-Wilzcek＇s work to research the Hawking radiation via tunneling from new form of rotating Kerr-Newman solution and obtain a corrected radiant spectrum, which is related to the change of Bekenstein-Hawking entropy, and is not pure thermal, but is consistent with the underlying unitary theory. Meanwhile, we point out that the information conservation is only suitable for the reversible process and in highly unstable evaporating black hole （irreversible process） the information loss is possible.

关键词： Kerr Newman black hole tunneling rate Bekenstein-Hawking entropy

Online hierarchical recognition method for target tactical intention in beyond-visual-range air combat

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defence Technology（防务技术） 2022年第8期18卷 1349-1361页

作者： Zhen Yang Zhi-xiao Sun Hai-yin Piao Ji-chuan Huang de-yun Zhou Zhang Ren School of Automation Science and Electrical Engineering Beihang UniversityBeijing100191China Northwestern Polytechnical University Xi'an710072China The First Military Representative Office of the Air Force Equipment department in Chengdu Chengdu610091China

Online accurate recognition of target tactical intention in beyond-visual-range (BVR) air combat is an important basis for deep situational awareness and autonomous air combat decision-making, which can create pre-emptive tactical opportunities for the fighter to gain air superiority. The existing methods to solve this problem have some defects such as dependence on empirical knowledge, difficulty in interpreting the recognition results, and inability to meet the requirements of actual air combat. So an online hierarchical recognition method for target tactical intention in BVR air combat based on cascaded support vector machine (CSVM) is proposed in this study. Through the mechanism analysis of BVR air combat, the instantaneous and cumulative feature information of target trajectory and relative situation information are introduced successively using online automatic decomposition of target trajectory and hierarchical progression. Then the hierarchical recognition model from target maneuver element, tactical maneuver to tactical intention is constructed. The CSVM algorithm is designed for solving this model, and the computational complexity is decomposed by the cascaded structure to overcome the problems of convergence and timeliness when the dimensions and number of training samples are large. Meanwhile, the recognition result of each layer can be used to support the composition analysis and interpretation of target tactical intention. The simulation results show that the proposed method can effectively realize multi-dimensional online accurate recognition of target tactical intention in BVR air combat.

关键词： Beyond-visual-range(BVR)air combat Tactical intention recognition Hierarchical recognition model Cascaded support vector machine(CSVM) Trajectory decomposition Maneuver element

Ignition and combustion modelling in a dual fuel diesel engine

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Propulsion and Power Research 2020年第2期9卷 116-131页

作者： R.de Robbio M.C.Cameretti R.Tuccillo department of Industrial Engineering University of Napoli Federico IIVia Claudio 2180125NaplesItaly

A numerical simulation of a single cylinder research diesel engine fuelled by natural gas and diesel oil in dual fuel mode was conducted to test the reaction mechanism presented by Li and Williams in Ref.[1]for methane *** mechanism made of only 9 reactions can represent a good compromise between reduction of computational time and accuracy of *** reproduce test cases previously carried out experimentally and numerically with a simpler kinetic mechanism at three different premixed ratios(10%,15% and 22%).Finally,a last case characterized by a supply of methane consistent with the typical load levels for this kind of engines(80%),was investigated only *** the simulations were performed with the KIVA-3V solver on a geometry which includes open valve periods,intake and exhaust *** a comparison between experimental and numerical results,a calibration of the model has been performed and a quite good fitting of the models has been achieved.

关键词： Diesel engine Combustion Methane Computational fluid dynamics(CFD)

Synthesis and Characterization of Layered Co_2(OH)_3(CH_3COO)·H_2O

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Chemical Research in Chinese Universities 2011年第6期27卷 910-914页

作者： ZHENG de-shan WANG Yan-zhong SHI Li-min SUN Si-xiu School of Materials and Chemical Engineering Xi＇an Technological University Xi＇an 710032 P. R. China School of Chemistry and Chemical Engineering Shandong University Jinan 250100 P. R. China

Layered hydroxide metal acetate Co2（OH）3（CH3COO）·H2O with an interlayer spacing of 1.282 nm has been synthesized by a novel method which is employed in ethanol-aqueous mixed solvents media. Experiment results show that the purity of the product by the modified method is higher compared with that by the previous methods. A complete characterization of the as-prepared samples was performed by means of X-ray powder diffraction, IR spectroscopy, scanning electron microscope, as well as magnetic measurement. The facile and effective approach for the preparation of this compound in this study is very interesting and important because it has wide application in the field of anionic exchange reaction for the synthesis of hybrid organic-inorganic compounds.

关键词： Anionic exchange reaction Hybrid organic-inorganic compound Layered hydroxide cobalt acetate Magnetic property