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FOURIER-CHEBYSHEV COEFFICIENTS AND GAUSS-TURAN QUADRATURE WITH CHEBYSHEV WEIGHT

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Journal of Computational mathematics 2003年第2期21卷 189-194页

作者： shijun yang {2. wang (department of mathematics, zhejiang University, hangzhou 3.002., china) department of mathematics Zhejiang University Hangzhou 310028

The main purpose of this paper is to derive an explicit expression for Fourier-Chebyshevcoefficientwhich is initiated by *** and***.

关键词： Fourier-Chebyshev coefficient Gauss-Turan quadrature

On solving equations of algebraic sum of equal powers

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Science china mathematics 2006年第9期49卷 1153-1157页

It is well known that a system of equations of sum of equal powers can be converted to an algebraic equation of higher degree via Newton's identities. This is the Viete-Newton theorem. This work reports the generalizations of the Viete-Newton theorem to a system of equations of algebraic sum of equal powers. By exploiting some facts from algebra and combinatorics,it is shown that a system of equations of algebraic sum of equal powers can be converted in a closed form to two algebraic equations, whose degree sum equals the number of unknowns of the system of equations of algebraic sum of equal powers.

关键词： algebraic sum of equal powers, Newton's identities, system of equations,roots of a polynomial.

Aqueous-phase formation of N-containing secondary organic compounds affected by the ionic strength

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Journal of Environmental Sciences 2024年第4期138卷 88-101页

作者： Yuqi Gan Xiaohui Lu Shaodong Chen xinghua Jiang Shanye yang Xiewen Ma Mei Li Fan yang Yewen Shi Xiaofei wang Shanghai Key Laboratory of Atmospheric Particle Pollution and Prevention Department of Environmental Science and EngineeringFudan UniversityShanghai 200433China Shanghai Institute of Pollution Control and Ecological Security Shanghai 200092China Guangdong Provincial Observation and Research Station for Coastal Atmosphere and Climate of the Great Bay Area Southern University of Science and TechnologyShenzhen 518055China Institute of Mass Spectrometry and Atmospheric Environment Guangdong Provincial Engineering Research Center for On-line Source Apportionment System of Air PollutionJinan UniversityGuangzhouChina Environmental Monitoring Station of Pudong New District Shanghai 201200China Shanghai Municipal Center for Disease Control&Prevention Shanghai 200336China

The reaction of carbonyl-to-imine/hemiaminal conversion in the atmospheric aqueous phase is a critical pathway to produce the light-absorbing N-containing secondary organic compounds(SOC).The formation mechanism of these compounds has been wildly investigated in bulk solutions with a low ionic ***,the ionic strength in the aqueous phase of the polluted atmosphere may be *** is still unclear whether and to what extent the inorganic ions can affect the SOC *** we prepared the bulk solution with certain ionic strength,in which glyoxal and ammonium were mixed to mimic the aqueous-phase *** characterization by High-resolution Mass Spectrometry was performed to identify the N-containing products,and the light absorption of the mixtures was measured by ultraviolet-visible ***-nine N-containing compounds were identified and divided into four categories(N-heterocyclic chromophores,high-molecular-weight compounds with N-heterocycle,aliphatic imines/hemiaminals,and the unclassified).It was observed that the longer reaction time and higher ionic strength led to the formation of more N-heterocyclic chromophores and the increasing of the lightabsorbance of the *** added inorganic ions were proposed to make the aqueous phase somewhat viscous so that the molecules were prone to undergo consecutive and intramolecular reactions to form the *** general,this study revealed that the enhanced ionic strength and prolonged reaction time had the promotion effect on the lightabsorbing SOC *** implies that the aldehyde-derived aqueous-phase SOC would contribute more light-absorbing particulate matter in the industrial or populated area where inorganic ions are abundant.

关键词： Ionic strength Carbonyl-to-imine/hemiaminal Heterocyclic Brown carbon Mass spectrometry Aqueous-phase reaction

Lipschitz continuity of best approximations and Chebyshev centers

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Chinese Science Bulletin 1998年第3期43卷 185-188页

作者： LI Chong 1 and wang xinghua 2.1. Center for Mathematical Sciences, {2. University, hangzhou 3.002., china 2. department of mathematics, hangzhou University, hangzhou 3.002., china Center for Mathematical Sciences Zhejiang University Hangzhou China department of mathematics Hangzhou University Hangzhou China

The Lipschitz continuity results are given for best approximations and Chebyshev centers. Consequently, the open problem presented by Septycki and Vleck is solved completely.

关键词： best approximation Chebyshev center uniform convexity.

TcPO_(2.changes are more pronounced than SpO_(2.changes during simulated altitude changes in a hypobaric oxygen chamber:a nonrandomized controlled trial

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Emergency and Critical Care Medicine 2024年第3期4卷 105-110页

作者： yang Li Liang Chen Ziyu Fu Zhiwei wang {2. Sun Xiaorong Luan Dedong Ma Tianliang Hu School of Nursing and Rehabilitation Shandong UniversityJinanShandongChina department of Emergency and Critical Care Medicine Qilu Hospital of Shandong UniversityJinanShandongChina department of Pulmonary and Critical Care Medicine Qilu Hospital of Shandong UniversityJinanShandongChina Emergency Management Center of State Grid Shandong Electric Power Company JinanShandongChina School of Nursing and Rehabilitation Cheeloo College of MedicineUniversity of ShandongDepartment of Infection ControlQilu Hospital of Shandong UniversityJinanShandongChina School of Mechanical Engineering Shandong UniversityKey Laboratory of the Ministry of Education for Efficient and Clean Machinery ManufacturingNational Experimental Teaching Demonstration Center for Mechanical EngineeringJinanShandongChina

Background:Hypoxia is a significant risk factor of ***,no studies have used transcutaneous tissue partial pressure of oxygen(TcPO_(2.)and partial pressure of carbon dioxide(TcPCO_(2.)monitors to measure the respective partial pressures in healthy *** saturation(SpO_(2.)is often used for traditional monitoring of vital *** study investigated the changes in TcPO_(2.and SpO_(2.values during rapid changes in *** trial was registered at ***(registration ***06076057).Methods:Healthy adult volunteers were instructed to sit vertically in a hypobaric oxygen chamber,which ascended from 0 m to 2.00 m at a uniform speed within 10 *** Danish Radiometer TCM4 was used to measure TcPO_(2.and TcPCO_(2.with the ventral side of the upper arm as the measurement *** Shenzhen Kerokan P0D-1 W pulse oximeter was used to measure heart rate and SpO_(2.,with values recorded once every 500 ***:Altogether,49 healthy volunteers were recruited between March 2.2. and August *** increasing altitude,TcPO_(2.and SpO_(2.decreased significantly(P2.began to change statistically at 500 m(P2.began to change statistically at 1000 m(P2.was greater than the difference in SpO_(2..At 1000 m,there were statistically significant changes in TcPO_(2.and SpO_(2.(P500 m,statistical significance was identified between TcPO_(2.in both sexes(P2.and heart rate was observed at the different elevations(P2.changed more dramatically than SpO_(2..

关键词： Altitude change Low-pressure oxygen chamber Transcutaneous oxygen saturation Transcutaneous partial pressure of oxygen

Defect Engineering and Carbon Supporting to Achieve Ni‑Doped CoP_(3) with High Catalytic Activities for Overall Water Splitting

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Nano-Micro Letters 2024年第11期16卷 569-584页

作者： Daowei Zha Ruoxing wang shijun Tian Zhong‑Jie Jiang Zejun Xu Chu Qin Xiaoning Tian Zhongqing Jiang department of Physics Zhejiang Sci-Tech UniversityHangzhou 310018People’s Republic of China department of Materials and Chemical Engineering Ningbo University of TechnologyNingbo 315211People’s Republic of China Guangzhou Key Laboratory for Surface Chemistry of Energy Materials Guangdong Engineering and Technology Research Center for Surface Chemistry of Energy MaterialsCollege of Environment and EnergySouth China University of TechnologyGuangzhou 510006People’s Republic of China

This work reports the use of defect engineering and carbon supporting to achieve metal-doped phosphides with high activities and stabilities for the hydrogen evolution reaction(HER)and the oxygen evolution reaction(OER)in alkaline ***,the nitrogen-doped carbon nanofiber-supported Ni-doped CoP_(3) with rich P defects(Pv·)on the carbon cloth(p-NiCoP/NCFs@CC)is synthesized through a plasma-assisted phosphorization *** p-NiCoP/NCFs@CC is an efficient and stable catalyst for the HER and the *** only needs overpotentials of 107 and 306 mV to drive 100 mA cm^(-2. for the HER and the OER,*** catalytic activities are higher than those of other catalysts reported *** high activities of the p-NiCoP/NCFs@CC mainly arise from its peculiar structural *** density functional theory calculation indicates that the Pv·richness,the Ni doping,and the carbon supporting can optimize the adsorption of the H atoms at the catalyst surface and promote the strong electronic couplings between the carbon nanofiber-supported p-NiCoP with the surface oxide layer formed during the OER *** gives the p-NiCoP/NCFs@CC with the high activities for the HER and the *** used in alkaline water electrolyzers,the p-NiCoP/NCFs@CC shows the superior activity and excellent stability for overall water splitting.

关键词： Plasma Electrocatalysis Hydrogen evolution reaction Oxygen evolution reaction Water splitting

Some results on numerical divided difference formulas

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Science china mathematics 2005年第11期48卷 1441-1450页

作者： wang xinghua,wang Heyu & Ming-Jun Lai department of mathematics, zhejiang University, hangzhou 3.002., china Computing Center, zhejiang University, hangzhou 310012. china department of mathematics, University of Georgia, Athens, GA 30602.7403, USA 1. department of mathematics Zhejiang University 310028 Hangzhou China 2. Computing Center Zhejiang University 310012 Hangzhou China 3. department of mathematics University of Georgia 30602-7403 Athens GA USA

The remainder estimates of numerical divided difference formula are given for the functions of lower and higher smoothness, respectively. Then several divided difference formulas with super-convergence are derived wit... 详细信息

关键词： numerical divided difference remainder estimate functions of lower smoothness sufficiently smooth functions super convergence.

Effect of SARS-CoV-2.infection in early pregnancy on placental development

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Science china(Life Sciences) 2024年第3期67卷 622-625页

作者： Shanru Yi Liping wang Mengting wang Wei Hong Ben Xu Xiaoying He Mengtian {2. Zhiping Wu Beiying wang Guang {2. shijun Shen Xinyu Cui Ruixue wang Kai wang Hong wang Xiaocui Li Shaorong Gao Cizhong Jiang Jiayu Chen Clinical and Translation Research Center of Shanghai First Maternity and Infant Hospital Shanghai Key Laboratory of Signaling and Disease ResearchSchool of Life Sciences and TechnologyTongji UniversityShanghai 200092China Key Laboratory of Spine and Spinal Cord Injury Repair and Regeneration of the Ministry of Education Orthopaedic Department of Tongji HospitalTongji UniversityShanghai 200065China Frontier Science Center for Stem cell Research Tongji UniversityShanghai 200092China Shanghai Key Laboratory of Maternal Fetal Medicine Shanghai First Maternity and Infant HospitalSchool of MedicineTongji UniversityShanghai 201204China

Dear Editor,Since the COVID-19 pandemic, the potential risks associated with maternal SARS-CoV-2.infection and its effect on fetal development have been a subject of considerable public concern. Previous studies have ... 详细信息

关键词： pregnancy fetal Effect

Selective synthesis of the B_(11)H_(14)^(-) and B_(12.H_(12.^(2.) borane derivatives and the general mechanisms of the B-H bond condensation

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Science china Chemistry 2024年第3期67卷 876-881页

作者： Yi Jing xinghua wang Hui Han Xin-Ran Liu Xing-Chao Yu Xi-Meng Chen Donghui Wei Lai-Sheng wang Xuenian Chen College of Chemistry Green Catalysis CenterZhengzhou UniversityZhengzhou 450001China School of Chemistry and Chemical Engineering Henan Key Laboratory of Boron Chemistry and Advanced Energy MaterialsHenan Normal UniversityXinxiang 453007China department of Chemistry Brown UniversityProvidenceRI 02912USA

Polyhedral boranes are a class of well-known boron molecular clusters with unique physical and chemical properties,and great efforts have been made in the past decades to find more effective synthetic ***,the established synthetic methods suffer from low efficiency and low selectivity because the mechanism of the B-H bond condensation reaction,critical for the synthesis of the polyhedral boranes,is not well *** we report highly selective and efficient synthetic methods of the salts of the tetradecahydridoundecaborate(1-)(B_(11)H^(-)_(14)) and dodecahydrido-dodecaborates(2.)(B_(12.H_(12.^(2.)) anions by employing commercially available and inexpensive starting *** theoretical and experimental investigations are carried out to elucidate the reaction *** have found that the nature of the B-H bond condensation is the dihydrogen bonding interaction in which the positively charged hydrogens(bridged hydrogens) play a crucial *** current study has not only led to more effective and selective synthetic methods for B_(11)H^(-)_(14) and B_(12.H_(12.^(2.) but also unveiled the nature of the B-H bond condensation and the general formation mechanisms of polyhedral *** finding will facilitate the development of more effective synthetic methods for polyhedral boranes and spur their wide application.

关键词： Boranes polyhedral boranes dihydrogen bond nucleophilicity