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Tartaric acid-assisted co-precipitation synthesis of Er^(3+)-doped Lu_2O_3 nanopowders

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Chinese Chemical Letters 2012年第11期23卷 1299-1302页

作者： Neng Li Wang xi yan zhang Peng He Wang School of Materials Science and Engineering Changchun University of Science and TechnologyChangchun 130022China

Erbium-doped lutetia nanopowders were synthesized by a novel co-precipitation method using tartaric acid as precipitant. The properties of the samples were investigated by Fourier transform infrared spectroscopy （FTIR）, X-ray diffraction （XRD）, TG-DSC, field emission scanning electron microscopy （FE-SEM）, and upconversion luminescence analysis. Pure cubic Lu2Oa nanopowders were directly obtained when the precursor was calcined at 800 ℃ for 2 h, the samples showed strong upconversion luminescence under excitation of 980 nm laser diode.

关键词： Co-precipitation Tartaric acid Erbium-doped lutetia Upconversion

Effectiveness and mechanisms of sodium-dependent glucose transporter 2 inhibitors in type 2 diabetes and heart failure patients

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World Journal of Cardiology 2024年第10期16卷 611-615页

作者： yan-xi zhang Hai-Sheng Hu Bao-Qing Sun Department of Clinical Laboratory The First Affiliated Hospital of Guangzhou Medical UniversityState Key Laboratory of Respiratory DiseaseNational Center for Respiratory MedicineNational Clinical Research Center for Respiratory DiseaseGuangzhou Institute of Respiratory HealthGuangzhou 510120Guangdong ProvinceChina

We comment on an article by GrubićRotkvićet al published in the recent issue of the World Journal of *** specifically focused on possible factors affecting the therapeutic effectiveness of sodium-dependent glucose transporter inhibitors(SGLT2i)in patients with type 2 diabetes mellitus(T2DM)and their impact on ***2i inhibits SGLT2 in the proximal tubules of the kidneys,lowering blood glucose levels by inhibiting glucose reabsorption by the kidneys and causing excess glucose to be excreted in the *** studies have demonstrated a role of SGLT2i in cardiovascular function in patients with diabetes who take metformin but still have poor glycemic *** addition,SGLT2i has been shown to be effective in anti-apoptosis,weight loss,and cardiovascular ***,it is feasible to treat patients with T2DM with cardiovascular or renal diseases using SGLT2i.

关键词： Sodium-dependent glucose transporter inhibitors Type 2 diabetes mellitus Heart failure Treatment Cardiovascular disease

Epidemiological characteristics of childhood obesity in eastern China, 2017-2019

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World Journal of Pediatrics 2019年第4期15卷 412-414页

作者： xi-yan zhang Wen-Yi yang Jie yang yan Wang Yao xiang Liu-Wei Gao Feng-Yun zhang Yong-Lin Zhou Department of Child and Adolescent Health Promotion Jiangsu Provincial Center for Disease Control and PreventionNo.172 Jiangsu RoadNanjing 210009China Public Health Research Institute of Jiangsu Province NanjingChina School of Public Health Southeast UniversityNanjingChina

Childhood obesity has becoming an increasing concern in many countries including China [1-3].Located in the eastern China,Jiangsu Province is one of the developed regions in China and is also facing this problem.

关键词： Childhood obesity Epidemiology Jiangsu province Risk factors

Preparation and Characterization of Three-dimensionally Ordered Crystalline Macroporous CeO_2

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Chinese Chemical Letters 2005年第8期16卷 1109-1112页

作者： xi yan zhang Tong Wen WANG Wen Qing JIANG Di WU Ling LIU Ai Hong DUAN Department of Chemistry Yunnan Normal University Kunming 650092

A stable 3DOM CeO2 with well-defined inverse opal microstructure and crystalline walls structure has been successfully synthesized by application of three-dimensional order PMMA beads as templates. Structural feature ... 详细信息

关键词： 3DOM CeO2 PMMA colloidal crystal template crystalline wall.

THE EFFECT OF OIL CAVITY DEPTH ON TEMPERATURE FIELD IN HEAVY HYDROSTATIC THRUST BEARING

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Journal of Hydrodynamics 2011年第5期23卷 676-680页

作者： SHAO Jun-peng DAI Chun-xi zhang yan-qin YU xiao-dong XU xiao-qiu WANG Yun-fei College of Mechanical and Power Engineering Harbin UniverSity of Science and Technology Harbin150080 China

For a heavy hydrostatic bearing with a high linear velocity, the results of numerical calculations often differ from practical conditions if the viscosity is considered as constant. In this article, the influence of the oil cavity depth on the temperature field in the heavy hydrostatic bearing is discussed in the context of variable viscosity. The viscosity-temperature relations for the gap oil film are first established by fitting B-Spline curves, then, numerical calculations for the temperature field in the heavy hydrostatic bearing of different oil cavity depths are carried out based on Finite Volume Method （FVM） under the same rotating speed, and the influence of the oil cavity depth on the temperature distribution in the gap oil film of the hydrostatic bearing is discussed. The results of numerical calculations provide the temperature distribution state inside the hydrostatic bearing, which would help the selection and the design of hydrostatic bearings in engineering practice.

关键词： hydrostatic thrust bearing viscosity-temperature characteristic Finite Volume Method (FVM) temperature field

Deciphering Water Oxidation Catalysts:The Dominant Role of Surface Chemistry over Reconstruction Degree in Activity Promotion

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Nano-Micro Letters 2025年第3期17卷 340-354页

作者： Li An Jianyi Li Yuanmiao Sun Jiamin Zhu Justin Zhu Yeow Seow Hong zhang Nan zhang Pinxian xi Zhichuan J.Xu Chun‑Hua yan State Key Laboratory of Applied Organic Chemistry Key Laboratory of Nonferrous Metal Chemistry and Resources Utilization of Gansu ProvinceFrontiers Science Center for Rare IsotopesCollege of Chemistry and Chemical EngineeringLanzhou UniversityLanzhou 730000People’s Republic of China School of Materials Science and Engineering Nanyang Technological UniversitySingapore 639798Singapore Faculty of Materials Science and Energy Engineering Institute of Technology for Carbon NeutralityShenzhen Institute of Advanced TechnologyChinese Academy of SciencesShenzhen 518055People’s Republic of China Key Laboratory of Electromagnetic Materials and Devices National Center for International Research On Photoelectric and Energy MaterialsSchool of Materials and EnergyElectron Microscopy CenterYunnan UniversityKunming 650091People’s Republic of China State Key Laboratory of Baiyunobo Rare Earth Resource Researches and Comprehensive Utilization Baotou Research Institute of Rare EarthsBaotou 014030People’s Republic of China Beijing National Laboratory for Molecular Sciences State Key Laboratory of Rare Earth Materials Chemistry and ApplicationsPKU‑HKU Joint Laboratory in Rare Earth Materials and Bioinorganic ChemistryPeking UniversityBeijing 100871People’s Republic of China

Water splitting hinges crucially on the availability of electrocatalysts for the oxygen evolution *** surface reconstruction has been widely observed in perovskite catalysts,and the reconstruction degree has been often correlated with the activity ***,a systematic study on the roles of Fe substitution in activation of perovskite LaNiO_(3)is *** substituting Fe content influences both current change tendency and surface reconstruction ***_(0.9)Fe_(0.1)O_(3)is found exhibiting a volcano-peak intrinsic activity in both pristine and reconstructed among all substituted perovskites in the LaNi_(1-x)Fe_(x)O_(3)(x=0.00,0.10,0.25,0.50,0.75,1.00)*** reconstructed LaNi_(0.9)Fe_(0.1)O_(3)shows a higher intrinsic activity than most reported NiFe-based ***,density functional theory calculations reveal that Fe substitution can lower the O 2p level,which thus stabilize lattice oxygen in LaNi0.9Fe0.1O3 and ensure its long-term ***,it is vital interesting that activity of the reconstructed catalysts relied more on the surface chemistry rather than the reconstruction *** effect of Fe on the degree of surface reconstruction of the perovskite is decoupled from that on its activity enhancement after surface *** finding showcases the importance to customize the surface chemistry of reconstructed catalysts for water oxidation.

关键词： Oxygen evolution reaction Perovskite oxides Doping Activation and reconstruction

Potassium ions and cyano group modified g-C_(3)N_(4) for effective generation of H_(2)O_(2) through two-electron oxygen reduction

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Science China Chemistry 2025年第1期68卷 192-200页

作者： Dongying Wang Shulan Pu Yongmin Chen Ke Lei Yujie Duan Linjiao Mao Xuhui Zeng xi Luo Yuntao zhang Yuqin Dong Jin Zhong zhang yan Sun School of Mechanical Engineering Chengdu UniversityChengdu 610106China Department of Chemistry and Biochemistry University of CaliforniaSanta CruzCA 95064USA

Potassium ions(K^(+))doped graphitic carbon nitride(g-C_(3)N_(4))was prepared by a thermal etching method using potassium hydroxide(KOH)as an ion *** transform infrared spectroscopy(FTIR)and X-ray photoelectron spectroscopy(XPS)results showed that the generation of the cyano group was detected while introducing K^(+).Under simulated sunlight irradiation,the sample with a K^(+)doping amount of 10%showed the highest hydrogen peroxide(H_(2)O_(2))generation rate of2,140.2μmol h^(-1)g^(-1).The apparent quantum yield(AQY)at 400 nm and the solar-to-chemical conversion(SCC)are 4.35%and1.23%,respectively.K^(+)acted as a bridge between g-C_(3)N_(4)layers,which enhanced charge transfer ***,the cyano group enhanced the adsorption capacity of protons(H^(+))and promoted the yield of H_(2)O_(2).The catalyst exhibited excellent photocatalytic stability based on four-cycle *** addition,a mechanism study showed that superoxide radicals(·O_(2)^(-))were the most important active species in the reaction *** production of H_(2)O_(2)was achieved through consecutive single-electron *** study deepens the understanding of the oxygen reduction reaction process and opens up a new venue for improving H_(2)O_(2)generation.

关键词： photocatalysis hydrogen peroxide oxygen reduction reaction potassium doping cyano group

The moment map for the variety of associative algebras

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Science China Mathematics 2025年第2期68卷 253-270页

作者： Hui zhang Zaili yan School of Mathematics Southeast UniversityNanjing 210096China School of Mathematics and Statistics Ningbo UniversityNingbo 315211China

We consider the moment map m:PV_(n)→iu(n)for the action of GL(n)on V_(n)=■^(2)(C^(n))^(∗)■C^(n),and study the critical points of the functional Fn=||m||2:PV_(n)→***,we prove that[μ]∈PV_(n) is a critical point if and only if Mμ=cμI+Dμfor some cμ∈R and Dμ∈Der(μ),where m([μ])=Mμ||μ||*** we show that any algebraμadmits a Nikolayevsky derivationϕμwhich is unique up to automorphism,and if moreover,[μ]is a critical point of Fn,thenϕμ=−1 cμDμ.Secondly,we characterize the maxima and minima of the functional Fn:A_(n)→R,where A_(n) denotes the projectivization of the algebraic varieties of all the n-dimensional associative ***,for an arbitrary critical point[μ]of Fn:A_(n)→R,we obtain a description of the algebraic structure ofμ.Finally,we classify the critical points of Fn:A_(n)→R for n=2 and n=3,respectively.

关键词： moment map variety of associative algebras critical point

An efficient conversion model between acceleration and pseudo-acceleration response spectra considering effects of magnitude,distance,and site class

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Earthquake Engineering and Engineering Vibration 2025年第1期24卷 15-30页

作者： Liu Zheng Zhao yan-Gang zhang Haizhong Key Laboratory of Urban Security and Disaster Engineering of Ministry of Education Beijing University of TechnologyBeijing 100124China Faculty of Agriculture Yamagata University1-23Wakaba-machiTsuruoka-shiYamagata 997-8555Japan

Both acceleration and pseudo-acceleration response spectra play important roles in structural seismic ***,only one of them is generally provided in most seismic ***,many studies have attempted to develop conversion models between the acceleration response spectrum(SA)and the pseudo-acceleration response spectrum(PSA).Our previous studies found that the relationship between SA and PSA is affected by magnitude,distance,and site ***,we developed an SA/PSA model incorporating these ***,this model is suitable for cases with small and moderate magnitudes and its accuracy is not good enough for cases with large *** paper aims to develop an efficient SA/PSA model by considering influences of magnitude,distance,and site class,which can be applied to cases not only with small or moderate magnitudes but also with large *** this purpose,regression analyses were conducted using 16,660 horizontal seismic records with a wider range of *** magnitude of these seismic records varies from 4 to 9 and the distances vary from 10 to 200 *** ground motions were recorded at 338 stations covering four site *** comparing them with existing models,it was found that the proposed model shows better accuracy for cases with any magnitudes,distances,and site classes considered in this study.

关键词： acceleration response spectrum pseudo-acceleration response spectrum magnitude distance site class