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highly Efficient and Selective Photocatalytic Nonoxidative Coupling of Methane to Ethylene over Pd-Zn Synergistic Catalytic Sites

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Research 2023年第1期2022卷 485-496页

作者： Yanduo Liu Yihong Chen Wenbin Jiang Tingting Kong Pedro h.C.Camargo chao Gao Yujie Xiong School of Chemistry and Materials Science University of Science and Technology of ChinaHefeiAnhui 230026China PInstitute of Energy hefei Comprehensive National Science Center HefeiAnhui230031China Key Laboratory of Functional Molecular Solids Ministry of EducationAnhui Engineering Research Center of Carbon Neutrality College of Chemistry and Materials ScienceAnhui Normal UniversityWuhuAnhui 241000China ADepartment of Chemistry University of HelsinkiFIN-00014Finland

Photocatalytic nonoxidative coupling of Ch_(4)to multicarbon(C^(2+))hydrocarbons(e.g.,C,h4)and h,under ambient conditions provides a promising energy-conserving approach for utilization of carbon ***,as the methyl intermediates prefer to undergo self-coupling to produce ethane,it is a challenging task to control the selective conversion of Ch to higher valueadded ***,we adopt a synergistic catalysis strategy by integrating Pd-Zn active sites on visible light-responsive defective WO_(3)nanosheets for synergizing the adsorption,activation,and dehydrogenation processes in Ch_(4)to C_(2)h_(4)*** from the synergy,our model catalyst achieves a remarkable C^(2+)compounds yield of 31.85μmolgh with an exceptionally high C,h4 selectivity of 75.3%and a stoichiometric h_(2)*** situ spectroscopic studies reveal that the Zn sites promote the adsorption and activation of Ch_(4)molecules to generate methyl and methoxy intermediates with the assistance of lattice oxygen,while the Pd sites facilitate the dehydrogenation of methoxy to methylene radicals for producing C_(2)h_(4)and suppress *** work demonstrates a strategy for designing efficient photocatalysts toward selective coupling of Ch_(4)to higher value-added chemicals and highlights the importance of synergistic active sites to the synergy of key steps in catalytic reactions.

关键词： oxidative synergistic coupling

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homotopy analysis solutions for the asymmetric laminar flow in a porous channel with expanding or contracting walls

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Acta Mechanica Sinica 2011年第2期27卷 208-214页

作者： X.-h. Si L.-C. Zheng X.-X. Zhang Y. chao Applied Science School University of Science and Technology Beijing 100083 Beijing China Department of Mechanical Engineering University of Science and Technology Beijing100083 Beijing China Research Institute of Chemical Defense of the EL.A 102205 Beijing China

In this paper, the asymmetric laminar flow in a porous channel with expanding or contracting walls is investigated. The governing equations are reduced to ordinary ones by using suitable similar transformations. homotopy analysis method （hAM） is employed to obtain the expres- sions for velocity fields. Graphs are sketched for values of parameters and associated dynamic characteristics, especially the expansion ratio, are analyzed in detail.

关键词： homotopy analysis method · Expanding or contracting wall · Asymmetric laminar flow · Porous channel · Expansion ratio

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Thiopurines are negatively associated with anthropometric parameters in pediatric Crohn's disease

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World Journal of Gastroenterology 2018年第18期24卷 2036-2046页

作者： Neera Gupta Robert h Lustig Cewin chao Eric Vittinghoff howard Andrews Cheng-Shiun Leu Division of Gastroenterology and Nutrition Department of Pediatrics Weill Cornell Medicine Division of Endocrinology Department of Pediatrics University of CaliforniaSan Francisco Department of Nutrition and Food Services University of CaliforniaSan Francisco Department of Epidemiology and Biostatistics University of CaliforniaSan Francisco Department of Biostatistics Mailman School of Public Health Columbia University Department of Biostatistics Columbia University Medical Center

AIM To determine the distribution of anthropometric parameter(AP)-z-scores and characterize associations between medications/serum biomarkers and AP-z-scores in pediatric Crohn's disease(CD).METhODS CD patients [hronological age(CA) 21 years] were enrolled in a cross-sectional study. Descriptive statistics were generated for participants' demographic characteristics and key variables of interest. Paired t-tests were used to compare AP-z-scores calculated based on CA(CA z-scores) and bone age(BA)(BA z-scores) for interpretation of AP's. Linear regression was utilized to examine associations between medications and serum biomarkers with AP-z-scores calculated based on CA(n = 82) and BA(n = 49). We reported regression coefficients as well as their corresponding p-values and 95% confidence *** Mean CA at the time of the study visit was 15.3 ± 3.5(SD; range = 4.8-20.7) years. Mean triceps skinfold(P = 0.039), subscapular skinfold(P = 0.002) and midarm circumference(MAC)(P = 0.001) BA z-scores were higher than corresponding CA z-scores. Medications were positively associated with subscapular skinfold [adalimumab(P = 0.018) and methotrexate(P = 0.027)] and BMI CA z-scores [adalimumab(P = 0.029)]. Azathioprine/6-mercaptopurine were negatively associated with MAC(P = 0.045), subscapular skinfold(P = 0.014), weight(P = 0.002) and BMI(P = 0.013) CA z-scores. ESR, CRP, and WBC count were negatively associated, while albumin and IGF-1 BA z-scores were positively associated, with specific AP z-scores(P height CA z-scores were higher in females, not males, treated with infliximab(P = 0.038). hemoglobin(P = 0.018) was positively associated, while platelets(P = 0.005), ESR(P = 0.003) and CRP(P = 0.039) were negatively associated with height CA z-scores in males, not females. CONCLUSION Our results suggest poor efficacy of thiopurines and a possible sex difference in statural growth response to infliximab in pediatric CD. Prospective longitudinal studie

关键词： Inflammatory bowel disease Azathioprine/6-mercaptopurine Biologics Nutrition

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Raman Spectroscopy of Garnet-group Minerals

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Chinese Journal Of Geochemistry 1994年第2期13卷 176-183页

作者：彭明生李迪恩 h.K.MAO E.C.T.chao Division of Quantum Mineralogy Department of Geology Central University of Technology Changsha China Geophysical Laboratory Carnegie Institution of Washington Washington D.C. USA U. S. Geological Survey 959 National Center Reston Virginia USA

The Raman spectra of the natural end members of the garnet-group minerals, which include pyrope, almandine and spessarite of Fe-Al garnet series and grossularite, andradite and uvarovite of Ca-Fe garnet series, have been studied. Measured Raman spectra of these minerals are reasonably and qualitatively assigned to the intemal modes, translational and rotatory modes of SiO4 tetrahedra,as well as the translational motion of bivalent cations in the X site. The stretch and rotatory Alg modes for the Fe-Al garnet series show obvious Raman shifts as compared with those for the Ca-Fe garnet series, owing to the cations residing in the X site connected with SiO4 tetrahedra by sharing the two edges. The Raman shifts of all members within either of the series are attributed mainly to the properties of cations in the X site for the Fe-Al garnet series and in the Y site for the Ca-Fe gamet series.

关键词：拉曼光谱石榴石榴子石铁铝榴石晶体结构

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A novel localization and orientation method for an objective embedded with a rectangle magnet

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high Technology Letters 2011年第1期17卷 39-45页

作者：阳万安 hu chao Max Q. - h. Meng Song Shuang Institute of Computing Technology Chinese Academy of Sciences Beijing 100190 P. R.China Shenzhen Institute of Advanced Integration Technology Chinese Academy of Sciences/The Chinese University of Hong Kong Shenzhen Institute of Advanced Technology CAS Shenzhen 518067 P. R. China Department of Electronic Engineering the Chinese University of Hong Kong Shatin Hong Kong China Graduate University of the Chinese Academy of Sciences Beijing P. R. China Department of Computer and Information Science Yi Bin University Yibin 644000 P. R. China

To wirelessly obtain the accurate location and orientation of an objective and exert an appropriate guidance for the objective, a feasible approach is to enclose a small rectangular permanent mag- net in the objective. The magnetic field, produced by the rectangular magnet can be detected by magnetic sensors outside the objective. With these sensor data, the 3D localization and 3D orienta- tion parameters can be computed based on the mathematic model of the rectangular magnet magnetic field. In this 6D localization and orientation system, we first obtain 5D parameters of the objective by dipole model, then based on these parameters we can obtain 6D parameters by the model of rectangular magnet magnetic field using the particle swarm optimization （PSO） algorithm. Simulation experiments show that the proposed approach achieves ~ood performance.

关键词： index terms -dipole 6D localization and orientation rectangular magnet PSO algorithm

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Laser capture microdissection and genetic analysis of carbon-labeled Kupffer cells

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World Journal of Gastroenterology 2009年第14期15卷 1708-1718页

作者： Stephan Gehring Edmond Sabo Maryann E San Martin Elizabeth M Dickson chao-Wen Cheng Stephen h Gregory Department of Medicine Rhode Island Hospital and The Warren Alpert Medical School of Brown University Providence RI 02903 United States Department of Pathology Rhode Island Hospital and The Warren Alpert Medical School of Brown University Providence RI 02903 United States zentrum fur Kinder- und Jugendmedizin der Universitaitsmedizin der Johannes Gutenberg-Universitait 55101 Mainz Germany

AIM： To develop a method of labeling and microdissecting mouse Kupffer cells within an extraordinarily short period of time using laser capture microdissection （LCM）. METhODS： Tissues are complex structures comprised of a heterogeneous population of interconnected cells. LCM offers a method of isolating a single cell type from specific regions of a tissue section. LCM is an essential approach used in conjunction with molecular analysis to study the functional interaction of cells in their native tissue environment. The process of labeling and acquiring cells by LCM prior to mRNA isolation can be elaborate, thereby subjecting the RNA to considerable degradation. Kupffer cell labeling is achieved by injecting India ink intravenously, thus circumventing the need for in vitro staining. The significance of this novel approach was validated using a cholestatic liver injury model. RESULTS： mRNA extracted from the microdissected cell population displayed marked increases in colonystimulating factor-1 receptor and Kupffer cell receptor message expression, which demonstrated Kupffer cell enrichment. Gene expression by Kupffer ceils derived from bile-duct-ligated, versus sham-operated, mice was compared. Microarray analysis revealed a significant （2.5-fold, q value 〈 10） change in 493 genes. Based on this fold-change and a standardized PubMed search, 10 genes were identified that were relevant to the ability of Kupffer cells to suppress liver injury. CONCLUSION; The methodology outlined herein provides an approach to isolating high quality RNA from Kupffer cells, without altering the tissue integrity.

关键词： Kupffer cells India ink Laser capturemicrodissection Bile duct ligation DNA microarray

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Double Star TC-1 observation of the earthward flowing plasmoids in the near magnetotail

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Chinese Science Bulletin 2007年第13期52卷 1843-1848页

作者： ZhANG YongCun LIU ZhenXing ShEN chao DUAN SuPing hE Zhaohai C M CARR h REME State Key Laboratory of Space Weather Center for Space Science and Applied Research Chinese Academy of Sciences Beijing 100080 China Graduate University of the Chinese Academy of Sciences Beijing 100049 China The Blackett Laboratory Imperial College London SW7 2BZ UK Centre d'Etudes Spatiale des Rayonnements BP 4346 31028 Toulouse Cedex 4 France

We analyze Double Star TC-1 magnetic field data from July to September in 2004 and find that plas-moids exist in the very near-Earth magnetotail. It is the first time that TC-1 observes the plasmoids inthe magnetotail at X > ?13 RE. According to the difference of the magnetic field structure in plasmoids,we choose two typical cases for our study: the magnetic flux rope on August 6 with the open magneticfield and the magnetic loop on September 14 with the closed magnetic field. Both of the cases are as-sociated with the high speed earthward flow and the magnetic loop is related to a strong substorm. Theions can escape from the magnetic flux rope along its open field line, but the case of the closed mag-netic loop can trap the ions. The earthward flowing plasmoids observed by TC-1 indicate that the mul-tiple X-line magnetic reconnection occurs beyond the distance of X=?10 RE from the earth.

关键词：磁层尾磁线圈焊接磁性

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A Unifi ed Geometric Rule for Designing Nanomagnetism in Graphene

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Nano Research 2008年第6期1卷 497-501页

作者： Decai Yu Elizabeth M.Lupton h.J.Gao chao Zhang Feng Liu Department of Materials Science and Engineering University of UtahSalt Lake CityUT 84112USA Institute of Physics Chinese Academy of ScienceBeijing 100080China School of Engineering Physics University of WollongongNSW 2522Australia

Based on the underlying graphene lattice symmetry and an itinerant magnetism model on a bipartite lattice,we propose a unifi ed geometric rule for designing graphene-based magnetic nanostructures:spins are parallel(ferromagnetic(FM))on all zigzag edges which are at angles of 0°and 120°to each other,and antiparallel(antiferromagnetic(AF))at angles of 60°and 180°.The rule is found to be consistent with all the systems that have been studied so *** the rule,we predict several novel graphene-based magnetic nanostructures:0-D FM nanodots with the highest possible magnetic moments,1-D FM nanoribbons,and 2-D magnetic superlattices.

关键词： Nanomagnetism graphene-based nanostructures magnetic ordering

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基于概念性水文模型与长短时记忆模型耦合的汉江上游流域径流模拟

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湖泊科学 2025年第1期37卷 279-292页

作者：邓超孙培源尹鑫邹佳成王卫光河海大学水文水资源学院南京210098 河海大学水灾害防御全国重点实验室南京210098 南京水利科学研究院水灾害防御全国重点实验室南京210029 赣江下游水文水资源监测中心宜春336000

为了探究概念性水文模型(GR4J)与长短时记忆模型(LSTM)耦合过程中物理模型参数反馈机制以及考虑土壤含水量作为中间变量对物理引导机器学习(PIML)模型径流模拟的影响,本研究构建了PIML模型并设置考虑参数反馈、考虑中间变量和两者同时... 详细信息

为了探究概念性水文模型(GR4J)与长短时记忆模型(LSTM)耦合过程中物理模型参数反馈机制以及考虑土壤含水量作为中间变量对物理引导机器学习(PIML)模型径流模拟的影响,本研究构建了PIML模型并设置考虑参数反馈、考虑中间变量和两者同时考虑的3种方案(依次简称为h1、h2、h3),以安康站为控制站的汉江上游流域开展实例研究。结果表明:(1)3种PIML模型径流模拟效果均优于LSTM模型,其中验证期纳什系数(NSE)平均提升10.6%,而PIML-h1与PIML-h3模型径流模拟效果优于GR4J模型,验证期NSE平均提升4.2%,其中PIML-h3模型在3种PIML模型中表现最佳,表明基于LSTM和GR4J模型构建的PIML模型对径流模拟效果有所改善,且同时考虑中间变量和参数反馈因素时对径流模拟效果改善最佳;(2)3种PIML模型对低水流量的模拟效果均优于GR4J和LSTM模型,且PIML-h3模型效果最佳,而对于高水流量,3种PIML模型均表现不佳,说明PIML模型往往在模拟低流量事件中更占优势;(3)3种PIML模型的径流模拟效果均表现出较强的季节性变化,PIML-h2和PIML-h3模型相较于PIML-h1模型受到的季节性变化影响更为明显,说明PIML模型模拟径流结果的季节性变化受到中间变量的影响。研究可为汉江上游流域径流模拟预报提供技术支撑。

关键词：物理引导机器学习径流模拟中间变量 GR4J LSTM 汉江

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The role of metal oxides on oxidant decay and disinfection byproduct formation in drinking waters: Relevance to distribution systems

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Journal of Environmental Sciences 2021年第12期33卷 140-149页

作者： chao Liu Key Laboratory of Drinking Water Science and Technology Research Center for Eco-Environmental SciencesChinese Academy of SciencesBeijing 100085China

Maintaining a residual disinfectant/oxidant(e.g., chlorine and chlorine dioxide), is a generally used strategy to control microbial contaminants and bacterial regrowth in distribution systems. Secondarily oxidant, such as hypobromous acid(hOBr), can be formed during chlorination of bromide-containing waters. The decay of oxidants and formation of disinfection byproducts(DBPs) due to the interaction between oxidants and selected metal oxides were studied. Selected metal oxides generally enhanced the decay of these halogencontaining oxidants via three pathways:(1) catalytic disproportionation to yield an oxidized form of halogen(i.e., halate) and reduced form(halide for chlorine and bromine or chlorite for chlorine dioxide),(2) oxygen formation, and(3) oxidation of a metal in a reduced form(e.g., cuprous oxide) to a higher oxidation state. Cupric oxide(Cu O) and nickel oxide(Ni O)showed significantly strong abilities for the first pathway, and oxygen formation was a side reaction. Cuprous oxide can react with oxidants via the third pathway, while goethite was not involved in these reactions. The ability of Cu O on catalytic disproportionation of hOBr remained stable up to four cycles. In chlorination process, bromate formation tends to be important(exceeding 10 μg/L) when initial bromide concentration is above 400 μg/L in the presence of dissolved organic matter. Increasing initial bromide concentrations increased the formation of DBPs and calculated cytotoxicity, and the maximum was observed at p h8.6 during chlorination process. Therefore, the possible disinfectant loss and DBP formation should be carefully considered in drinking water distribution systems.

关键词： Cupric oxide Disproportionation Bromine Bromate Chlorine dioxide Chlorate

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