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Kinetic study of hydrodesulfurization of coker gas oil in a slurry reactor

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Frontiers of Chemical Science and Engineering 2013年第2期7卷 139-144页

作者： Haiding xiang Tiefeng wang Beijing Key Laboratory of Green Reaction Engineering and Technology Department of Chemical Engineering Tsinghua University Beijing 100084 China

Coker gas oil （CGO） is a poor-quality feed- stock for ftuidized bed catalytic cracking （FCC） or hydrocracking. The pretreatment of CGO, especially hydrotreating, can significantly improve the product quality and protect the catalyst. In this work, we studied the hydrodesulfurization （HDS） of CGO in a slurry reactor. All the experiments were carried out in an autoclave using a NiMo/A1203 catalyst at reaction temperature 340℃- 400℃, pressure 6-10 MPa, and stirring speed 800 r. mn^-1, with hydrogen-to-oil ratio in the range of 500-1500. The effects of the operating parameters on the desulfurization ratio were investigated and discussed. A macro reaction kinetic model was established for the HDS of CGO in the slurry reactor.

关键词： coker gas oil hydrodesulfurization slurryreactor reaction kinetic model

成都市预包装非真空冷藏即食熟肉制品中单核细胞增生李斯特菌定量风险评估

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四川大学学报(医学版) 2025年第1期56卷 239-246页

作者：刘肖孙宏虎王翔刘丽莎郭婷孙悦王军白莉国家食品安全风险评估中心国家卫生健康委食品安全风险评估重点实验室北京100021 成都市食品检验研究院辐照保藏四川省重点实验室成都610045 上海理工大学健康科学与工程学院上海200093 广东海洋大学食品科技学院湛江524088

目的应用@Risk软件,对成都市预包装非真空短保质期即食熟肉制品中单核细胞增生李斯特菌(Listeria monocytogenes,LM)进行定量风险评估。方法使用前期研究获得的成都市预包装非真空冷藏即食熟肉制品中LM污染监测数据,建立风险评估模型,... 详细信息

目的应用@Risk软件,对成都市预包装非真空短保质期即食熟肉制品中单核细胞增生李斯特菌(Listeria monocytogenes,LM)进行定量风险评估。方法使用前期研究获得的成都市预包装非真空冷藏即食熟肉制品中LM污染监测数据,建立风险评估模型,结合从零售到消费阶段LM在熟肉制品中的生长情况,对不同人群因食用熟肉制品导致LM感染的风险进行定量风险评估。结果成都市每年每百万5~<65岁健康人群通过预包装非真空冷藏熟肉制品导致李斯特菌病的潜在病例数为0.01人〔95%置信区间(confidence interval,CI):0~1.71×10^(-2)〕,65岁及以上健康人群为0.22人(95%CI:0~2.67×10^(-1)),孕妇为2.88人(95%CI:3.85×10^(-8)~4.35)。根据敏感性分析结果,零售时LM初始污染水平是影响患病率最重要的因素(R=0.25),其他因素依次是零售温度(R=0.08)、零售时长(R=0.07)和每餐消费量(R=0.07)等。结论对于预包装非真空熟肉制品,降低李斯特菌病患病率最主要的措施为控制初始污染水平,要求食品加工厂对加工环境和设备定期清洁和严格消毒,从源头减少LM的污染。零售熟食店应严格控制贮存温度不超过5.0℃并按照保质期销售。消费者购买后应尽快食用或置于冷藏条件下贮存、缩短贮存时间,孕妇人群食用前应彻底加热,从而减少李斯特菌病的发生。

关键词：单增李斯特菌定量风险评估即食熟肉制品敏感性分析

On the Construction and Analysis of Finite Volume Element Schemes with Optimal L^(2) Convergence Rate

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Numerical Mathematics(Theory,Methods and Applications) 2021年第1期14卷 47-70页

作者： xiang wang Yuqing Zhang School of Mathematics Jilin UniversityChangchun 130012China

We provide a general construction method for a finite volume element(FVE)scheme with the optimal L^(2)convergence *** k-(k-1)-order orthogonal condition(generalized)is proved to be a sufficient and necessary condition for a k-order FVE scheme to have the optimal L^(2) convergence rate in 1D,in which the independent dual parameters constitute a(k-1)-dimension surface in the reasonable domain in *** the analysis,the dual strategies in different primary elements are not necessarily to be the same,and they are allowed to be asymmetric in each primary element,which open up more possibilities of the FVE schemes to be applied to some complex problems,such as the convection-dominated *** worth mentioning that,the construction can be extended to the quadrilateral meshes in *** stability and H^(1) estimate are proved for *** the above results are demon-strated by numerical experiments.

关键词： Finite volume L^(2)estimate sufficient and necessary condition orthogonal condition

Solutions for Schrodinger-Poisson system involving nonlocal term and critical exponent

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Applied Mathematics(A Journal of Chinese Universities) 2023年第3期38卷 357-372页

作者： MO Xiu-ming MAO An-min wang xiang-xiang School of Biomedicine Beijing City UniversityBeijing 100094China School of Mathematical Sciences Qufu Normal UniversityQufu 273165China.

In this paper,we consider the following Kirchhoff-Schrodinger-Poisson system:{−(a+b∫_(R^(3))|∇u|^(2))△u+u+ϕu=μQ(x)|u|^(q-2)u+K(x)|u|^(4)u,in R^(3),−△ϕ=u^(2) the nonlinear growth of|u|^(4)u reaches the Sobolev critical *** combining the variational method with the concentration-compactness principle of Lions,we establish the existence of a positive solution and a positive radial solution to this problem under some suitable *** nonlinear term includes the nonlinearity f(u)~|u|^(q-2)u for the well-studied case q∈[4,6),and the less-studied case q∈(2,3),we adopt two different strategies to handle these *** result improves and extends some related works in the literature.

关键词： variational methods critical exponent concentration-compactness principle

Newly developed techniques in andrology, endoscopy of the vas deference and a new imaging technique for in situ localization of vital spermatozoa

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Asian Journal of Andrology 2013年第6期15卷 721-722页

作者： xiang wang Department of Urology Huashan Hospital FudanUniversity Shanghai 200040 China

During the past decade, endourology represents the most advanced tech-nology in urology which has provided mi- nimal invasive diagnostic and therapeutic tool for patients with urology diseases. However, because of the much smaller lumen of genital tract, endoscopic andro-logy remained a dream for andrologists until the first clinical application of vesicu-loscopy in laser lithotripsy of seminal vesi-cle stones in 2006. Lately, Dr Trottmann at Ludwig-Maximilians University, Germany, for the first time established vasoscopy in the seminal duct using a new prototype of a microendoscope and also applied a new imaging technique for in situ localization of vital spermatozoa. These newly developed techniques will greatly speed up the clinical practice of endoandrology.

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Characteristic mineralogy of the Zhutishi granite:Implication for petrogenesis of the late intrusive granite

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Science China Earth Sciences 2006年第6期49卷 573-583页

作者： wang xiang YAO Xiaojuan wang Chuansheng State Key Laboratory for Mineral Deposit Research Department of Earth Sciences Nanjing University Nanjing 210093 China State Key Laboratory for Mineral Deposit Research Department of Earth Sciences Nanjing University Nanjing 210093 China State Key Laboratory for Mineral Deposit Research Department of Earth Sciences Nanjing University Nanjing 210093 China

Many late intrusive granites with strongly peraluminous composition and fine-grained tex-ture occur as stocks or apophysis in the Dadongshan main intrusive granite located in NW Guang-dong Province. This paper reports the results of a petrogenetic study of some characteristic minerals (zircon, muscovite and andalusite) from the Zhutishi granite, one of the late intrusive granites in the Dadongshan granite. It is observed that the typological pattern of zircon population in the Zhutishi granite differs significantly from that in the Dadongshan granite, and that muscovite and andalusite, only found in the Zhutishi granite, are of magmatic origin. Therefore, this paper considers that the Zhutishi granite was unlike to be produced through crystal fractionation from the Dadongshan granitic magma as reported by previous authors, but is related closely to the formation of the Dadongshan granite. The hydrothermal fluid, produced by differentiation of the Dadongshan granitic magma at deep magmatic chamber, would penetrate into the source rock of the Zhutishi granite, and make it enriched in H2O and Al2O3; and the decompression after the ascent of the Dadongshan granitic magma in extension regime promotes partial melting of the source rock of the Zhutishi granite, and produces the strongly peraluminous granitic magma. The model proposed in this paper seems to be more reasonable to explain the spacio-temporal relationship between the late intrusive granites with strongly peraluminous feature and the main intrusive granite with metaluminous feature.

关键词： late intrusive granite, main intrusive granite, zircon, muscovite, andalusite.

Regularity for a Class of Singular Complex Hessian Equations

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Acta Mathematica Sinica,English Series 2021年第11期37卷 1709-1720页

作者： Jia xiang wang Bin ZHOU School of Mathematical Sciences Zhejiang UniversityHangzhou 310027P.R.China School of Mathematical Sciences Peking UniversityBeijing 100871P.R.China

In this paper,we study the regularity of the complex Hessian equation when the right hand has pole *** show the Holder continuity of the solution to the Dirichlet *** particular,for the complex Monge-Ampère equation,... 详细信息

关键词： Complex Hessian equation singularity regularity

Searching forγ-ray counterparts to very faint X-ray transient neutron star binaries

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Research in Astronomy and Astrophysics 2018年第9期18卷 47-52页

作者： Ge-Ge wang Zhong-xiang wang Shanghai Astronomical Observatory Chinese Academy of SciencesShanghai 200030China University of Chinese Academy of Sciences Beijing 100049China

Very faint X-ray transients （VFXTs） are a group of X-ray binaries with low luminosities, displaying peak X-ray luminosities during their outbursts of only 1034-1036 erg s^-1. Using γ-ray data obtained with the Large Area Telescope （LAT） onboard the Fermi Gamma-Ray Space Telescope （Fermi）, we investigate their possible nature of containing rotation-powered pulsars, or more specifically being transitional millisecond pulsars （MSPs）. Among more than 40 known VFXTs, we select 12 neutron star systems. We analyze the LAT data for the fields of 12 VFXTs in the energy range 0.2-300GeV, but do not find any counterparts likely detected by Fermi. We obtain luminosity upper limits for the 12 sources. While the distances to the sources are largely uncertain, the upper limits are comparable to the luminosities of two transitional systems, PSR J1023-0038 and XSS J12270-4859. From our study, we conclude that no evidence is found at γ-rays for the suggestion that some VFXTs could contain rotation-powered MSPs （or be transitional MSP systems）.

关键词： stars pulsars - stars binaries - gamma rays stars

Progress in Treatment of Gout Using Chinese and Western Medicine

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Chinese Journal of Integrative Medicine 2020年第1期26卷 8-13页

作者： wang xiang wang Yan-gang Department of Endocrinology The Affiliated Hospital of Medical College Qingdao University

Gout is a crystal-related arthropathy resulting from the deposition of monosodium urate. Identifying appropriate treatments and novel drugs to decrease serum uric acid(SUA) levels and gout risk has been a major focus. By performing extensive literature review on the pathogenesis and Chinese and Western medicine treatment of gout, this paper aimed to identify novel targets for effective control of acute gout attacks and long-term reduction of SUA. In addition, we aimed to provide new directions for the improvement of therapeutic measures and the development of drugs. Although Western medicine can significantly contribute to the treatment of gout, Chinese herbal medicine has unique advantages, including reduced adverse reactions and higher patient compliance. It may also fill in the shortcomings of Western medicine in the intermittent period treatment of gout. In addition to constantly exploring pathogenesis and drug targets, research on Chinese herbal medicine is equally important. The combination of Chinese and Western medicine has proven to become an important direction for gout treatment.

关键词： gout therapy research progress Chinese medicine Western medicine