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Tuning active sites in MoS_(2)-based catalysts via H_(2)O_(2)etching to enhance hydrodesulfurization performance

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Petroleum Science 2023年第6期20卷 3875-3886页

作者： Shui-Sen He Ting-Ting Huang Chao chen Yu fan State Key Laboratory of Heavy Oil Processing China University of PetroleumBeijing102249China State Key Laboratory Base for Eco-Chemical Engineering in College of Chemical Engineering Qingdao University of Science and TechnologyZhengzhou Road 53Qingdao266042ShandongChina

A H_(2)O_(2)etching strategy was adopted to introduce coordinatively unsaturated sites(CUS)on MoS_(2)-based catalysts for dibenzothiophene(DBT)hydrodesulfurization(HDS).The CUS concentrations on MoS_(2) slabs were finely regulated by changing the concentrations of H_(2)O_(2)*** the increasing H_(2)O_(2)concentrations(0.1–0.3 mol/L),The CUS concentrations on MoS_(2) slabs increased ***,the high-concentration H_(2)O_(2)etching(0.5 mol/L)increased the MoOxSy and MoO_(3) contents on MoS_(2) slabs compared to etching with the H_(2)O_(2)concentration of 0.3 mol/L,which led to the less CUS concentration in the sulfided Mo–H-0.5 catalyst than in the sulfided Mo–H-0.3 catalyst.A microstructure-activity correlation indicated that the CUS introduced by H_(2)O_(2)etching on MoS_(2) slabs significantly enhanced DBT *** Co loadings were further introduced into Mo–H-0.3,which had the most CUS concentration,and the corresponding 0.2-CoMo catalyst with the highest CoMoS content(3.853 wt%)exhibited the highest reaction rate constant of 6.95×10^(−6)mol g^(−1)s^(−1)among these CoMo catalysts.

关键词： H_(2)O_(2)etching Coordinatively unsaturated site concentrations CoMoS Hydrodesulfurization

王书臣治疗铜绿假单胞菌定植的支气管扩张症撷英

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中华中医药杂志 2024年第2期39卷 779-783页

作者：张雯周瑞玲何沂王冰丛晓东樊茂蓉张琼中国中医科学院研究生院北京100700 中国中医科学院西苑医院北京100091

文章总结王书臣教授治疗铜绿假单胞菌定植的支气管扩张症经验。认为铜绿假单胞菌定植的支气管扩张症病机属本虚标实,可从中医“三焦失调,伏毒久羁”角度认识该疾病发生发展过程,提出“祛邪序贯全程,补虚治取脾肾”的治疗原则,以培土生... 详细信息

文章总结王书臣教授治疗铜绿假单胞菌定植的支气管扩张症经验。认为铜绿假单胞菌定植的支气管扩张症病机属本虚标实,可从中医“三焦失调,伏毒久羁”角度认识该疾病发生发展过程,提出“祛邪序贯全程,补虚治取脾肾”的治疗原则,以培土生金、金水相生之法固本培元,善用“清”“透”二法祛邪透毒,并经通利三焦以助邪外出,兼以临证加减,助患者机体气机通畅、水液温化和阴阳平衡,减少铜绿假单胞菌定植的支气管扩张症患者每年急性加重次数,改善生活质量。

关键词：王书臣支气管扩张症铜绿假单胞菌三焦伏毒名医经验清透

Wastewater reclamation and reuse in China:Opportunities and challenges

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Journal of Environmental Sciences 2016年第1期28卷 86-96页

作者： Sidan Lyu Weiping chen Weiling Zhang Yupeng fan Wentao Jiao State Key Laboratory for Urban and Regional Ecology Research Center for Eco-Environmental SciencesChinese Academy of SciencesBeijing 100085China University of Chinese Academy of Sciences Beijing 100049China

The growing water stress both in terms of water scarcity and quality deterioration promotes the development of reclaimed water as a new water resource use. This paper reviewed wastewater reuse practices in China, and the opportunities and challenges of expanding reclaimed water use were analyzed. Rapid urbanization with the increasing of water demand and wastewater discharge provides an opportunity for wastewater reuse. The vast amount of wastewater discharge and low reclaimed water production mean that wastewater reuse still has a great potential in China. Many environmental and economic benefits and successful reclamation technologies also provide opportunities for wastewater reuse. In addition, the overall strategy in China is also encouraging for wastewater reuse. In the beginning stage of wastewater reclamation and reuse, there are many significant challenges to expand wastewater reuse in China including slow pace in adopting urban wastewater reuse programs, the establishment of integrated water resources management framework and guidelines for wastewater reuse programs, incoherent water quality requirements, the limited commercial development of reclaimed water and the strengthening of public awareness and cooperation among stakeholders.

关键词： Wastewater reuse Urbanization Policy Integrated water resource management Public acceptance

DNS analysis of incipient drop impact dynamics using an accurate level set method

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Chinese Journal of Chemical Engineering 2017年第1期25卷 1-10页

作者： Min Chai Kun Luo Changxiao Shao Song chen Jianren fan State Key Laboratory of Clean Energy Utilization Zhejiang University Hangzhou 310027 China

A series of 2D direct numerical simulations were performed with an accurate level set method for single drop *** adopted ACLS method was validated to be efficient with perfect mass conservation in both normal and oblique impacts.A square-root correction for neck bases was modified in accuracy as well as scope of *** addition,process of jet formation and evolution was studied to reveal internal dynamics in drop ***'s found that pressure gradient and vortex are coexisting and completive reasons for jet topology while the inclined angle has a significant effect on *** of jet formation and evolution are different in the front and back *** the help of PDF distribution and correction calculation,a compromise in the competition is *** work lays a solid foundation for further studies of dynamics in gas-liquid flows.

关键词： Numerical simulation Accurate level set Gas-liquid flow Interface Mechanism completion Compromise

Thermal Influence of the Couette Flow in a Hydrostatic Spindle on the Machining Precision

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Chinese Journal of Mechanical Engineering 2013年第3期26卷 427-436页

作者： chen Dongju fan Jinwei LI Haiyong WANG Xiaofeng ZHANG Feihu College of Mechanical Engineering and Applied Electronics Technology Beijing University of Technology School of Mechatronics Engineering Harbin Institute of Technology

Hydrostatic spindles are increasingly used in precision machine tools. Thermal error is the key factor affecting the machining accuracy of the spindle, and research has focused on spindle thermal errors through examination of the influence of the temperature distribution, thermal deformation and spindle mode. However, seldom has any research investigated the thermal effects of the associated Couette flow. To study the heat transfer mechanism in spindle systems, the criterion of the heat transfer direction according to the temperature distribution of the Couette flow at different temperatures is deduced. The method is able to deal accurately with the significant phenomena occurring at every place where thermal energy flowed in such a spindle system. The variation of the motion error induced by thermal effects on a machine work-table during machining is predicated by establishing the thermo-mechanical error model of the hydrostatic spindle for a high precision machine tool. The flow state and thermal behavior of a hydrostatic spindle is analyzed with the evaluated heat power and the coefficients of the convective heat transfer over outer surface of the spindle are calculated, and the thermal influence on the oil film stiffness is evaluated. Thermal drift of the spindle nose is measured with an inductance micrometer, the thermal deformation data 1.35 μm after running for 4 h is consistent with the value predicted by the finite element analysis’s simulated result 1.28 μm, and this demonstrates that the simulation method is feasible. The thermal effects on the processing accuracy from the flow characteristics of the fluid inside the spindle are analyzed for the first time.

关键词： hydrostatic spindle Couette flow finite element simulation convective heat transfer thermal deformation

Evidence from pseudomorphous β-quartz phenocryst for decompression of rock-forming and ore-forming processes in Shapinggou porphyry Mo deposit

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Science China Earth Sciences 2016年第5期59卷 1014-1024页

作者： HE Jun XU XiaoChun XIE QiaoQin fan ZiLiang chen TianHu School of Resources and Environmental Engineering Hefei University of Technology Laboratory for Nanomineralogy & Environmental Material Hefei University of Technology

The Shapinggou porphyry molybdenum(Mo) deposit, located in Jinzhai County, Anhui Province, China, is the largest in the Qinling-Dabie Mo Metallogenic Belt. The intrusive rocks in the Shapinggou Mo ore district formed in the Yanshanian can be divided into two stages based on zircon U-Pb dating and geochemical features. This study focuses on the late stage intrusions(quartz syenite and granite porphyry), which are closely genetically related to molybdenum mineralization. Petrographic observations identified two quartz polymorphs in the quartz syenite and granite porphyry, which were derived from the same magmatic sources and similar evolutionary processes. The quartzes were identified as a xenomorphic β-quartz within quartz syenite, while the quartz phenocrysts within the granite porphyry were pseudomorphous b-quartz, characterized by a hexagonal bipyramid crystallography. The pseudomorphous b-quartz phenocrysts within the granite porphyry were altered from b-quartz through phase transformation. These crystals retained b-quartz pseudomorph. Combined with titanium-inzircon thermometry, quartz phase diagrams, and granitic Q-Ab-Or-H_2O phase diagrams, it is suggested that the quartz syenite and granite porphyry were formed under similar magmatic origins, including similar depths and magmatic crystallization temperatures. However, the β-quartz within quartz syenite indicated that the crystallization pressure was greater than 0.7 GPa, while the original b-quartz within the granite porphyry was formed under pressures between 0.4 and 0.7 GPa. The groundmass of the granite porphyry which formed after the phenocryst indicated a crystallizing pressure below 0.05 GPa. This indicates that the granite porphyry was formed under repetitive and rapid decompression. The decompression was significant as it caused the exsolution of the ore-forming fluids, and boiling and material precipitation during the magmatic-fluid process. The volumetric difference during the phase transformation f

关键词： Porphyry Mo deposit Pseudomorphous β-quartz Decompression mechanism Rock-forming and ore-forming processes Shapinggou Mo deposit

城市景观湖泊不同时间尺度CH4通量特征及影响因素分析——以南京市莫愁湖为例

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湖泊科学 2024年第3期36卷 782-793页

作者：次珍谢舒恬张一泉柯凡尹一帆谢璇林晗琪陈新芳冯慕华河海大学水文水资源学院南京210098 中国科学院南京地理与湖泊研究所湖泊与环境国家重点实验室南京210008 湖南农业大学水利与土木工程学院长沙410128 中国科学院大学北京100049 南京信息工程大学应用气象学院南京210044

城市景观湖泊对温室气体的收支发挥着重要作用。本文以南京市莫愁湖为研究对象,采用静态箱—温室气体分析仪法实时监测湖泊水—气界面CH_(4)通量,分析湖泊主要温室气体CH_(4)在日尺度和季节尺度上因冒泡和扩散排放方式不同对其通量的影... 详细信息

城市景观湖泊对温室气体的收支发挥着重要作用。本文以南京市莫愁湖为研究对象,采用静态箱—温室气体分析仪法实时监测湖泊水—气界面CH_(4)通量,分析湖泊主要温室气体CH_(4)在日尺度和季节尺度上因冒泡和扩散排放方式不同对其通量的影响,探究影响湖泊CH_(4)通量的因素。结果表明:(1)在日尺度上,四季24 h内CH_(4)均呈排放状态,受白天冒泡影响,四季CH_(4)总通量均存在白天高于夜间的日变化特征。(2)在季节尺度上,莫愁湖CH_(4)排放通量呈现显著的时空异质性,受冒泡通量的影响夏季CH_(4)通量明显高于春、秋、冬三季;B区的CH_(4)总通量(6.04 nmol/(m^(2)·s))显著高于A区(3.82 nmol/(m^(2)·s)),水体的营养化程度和离岸距离是空间变化的主要影响因素。A、B两区CH_(4)排放夏季以冒泡排放为主,春、秋、冬以扩散排放为主。(3)在日尺度上,CH_(4)通量受气温、水温、辐射和风速等气象要素影响,与水质参数间的关系不显著;在季节尺度上,CH_(4)通量与温度(气温、水温)、水体营养盐水平、叶绿素a浓度及富营养化程度的时间变化相一致,也随着水体透明度、pH和氧化还原电位的减小而呈增加的趋势。本研究为准确估算城市湖泊CH_(4)排放量提供重要的数据基础。

关键词：城市景观湖泊莫愁湖甲烷日尺度季节尺度

某院479株耐甲氧西林金黄色葡萄球菌分布及耐药性分析

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江苏预防医学 2024年第1期35卷 88-91页

作者：杜凤英刘一凡南京医科大学附属宿迁第一人民医院江苏宿迁223800

目的回顾分析宿迁市第一人民医院住院患者耐甲氧西林金黄色葡萄球菌(MRSA)的检出、分布及耐药情况,为有效控制医院内感染提供依据。方法应用杏林实时监测系统,收集该院2019—2022年住院患者中分离出的MRSA并进行统计分析。结果共分离出... 详细信息

目的回顾分析宿迁市第一人民医院住院患者耐甲氧西林金黄色葡萄球菌(MRSA)的检出、分布及耐药情况,为有效控制医院内感染提供依据。方法应用杏林实时监测系统,收集该院2019—2022年住院患者中分离出的MRSA并进行统计分析。结果共分离出金黄色葡萄球菌1054株,其中MRSA 479株,平均检出率45.45%。MRSA科室分布前5位依次是儿科(18.16%)、重症医学科(16.70%)、普通外科(9.60%)、中医烧伤科(8.77%)、耳鼻喉口腔科(7.72%)。标本主要来源于痰液(49.06%)和创面分泌物(35.07%)。感染部位主要是下呼吸道感染(48.85%)、皮肤软组织感染(16.08%)。感染类型中社区获得性感染占比最高(51.77%),其次是院内感染(14.61%)和定植(33.61%)。新生儿科和儿科以社区获得性感染为主,神经外科和重症医学科以院内感染为主。MRSA对头孢西丁、青霉素和苯唑西林的耐药率均是100.00%,对喹诺酮类耐药率均在9%以下,对红霉素及克林霉素的耐药率均在60%以上,对替加环素、万古霉素、利奈唑胺、呋喃妥因等耐药率均为0。结论该院MRSA检出率较高,对常用抗菌药物呈不同程度耐药,感控部门要对MRSA检出率高和院内感染发生率高的科室加强防控措施落实督查,减少MRSA在院内感染或流行。

关键词：耐甲氧西林金黄色葡萄球菌(MRSA) 医院内感染耐药性

A unified model of bidirectional reflectance distribution function for the vegetation canopy

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Science China Earth Sciences 2017年第3期60卷 463-477页

作者： XU XiRu fan WenJie LI JuCai ZHAO Peng chen GaoXing Institute of Remote Sensing and Geographic Information System Peking UniversityBeijing 100871China Beijing Key Laboratory of Spatial Information Integration&Its Applications Beijing 100871China

An accurate and operational bidirectional reflectance distribution function （BDRF） canopy model is the basis of quantitative vegetation remote sensing. The canopy reflectance should be approximated as the sum of the single scattering reflectance arising from the sun, pl, and the multiple scattering reflectance arising from the canopy, fin, as their directional characteristics are dramatically different. Based on the existing BRDF model, we obtain a new analytical expression of ρ1 and ρm in this paper, which is suitable for different illumination conditions and different vegetation canopies. According to the geometrical optic model at the leaf scale, the anisotropy of ρ1 can be ascribed to the geometry of the object, sun and the sensor, multiple scale clumping, and the fraction of direct solar radiation and diffuse sky radiation. Then, we parameterize the area ratios of four components： the sunlit foliage, sunlit ground, shadow foliage and shadow ground based on a Poisson distribution, and develop a new approximate analytical single scattering reflectance model. Assuming G=0.5, a recollision probability theory based scattering model is developed which considers the effects of diffuse sky radiation, scattering inside the canopy and rebounds between the canopy and soil. Validation using ground measurements of maize and black spruce forest proves the reliability of the model.

关键词： Vegetation BRDF Unified model Clumping Index Proportion of direct solar radiation and diffuse sky radiation Recollision probability