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Journal of Materials Science & Technology 2018年第2期34卷 403-408页

作者： Hai-Bin Li Na Xu Yi-Hua fang Hui Fan z. Lei Min-fang Han School of Chemical and Environmental Engineering China University of Mining & Technology State Key Laboratory of Power Systems Department of Thermal Engineering Tsinghua University

Fluidiz.d bed reactor is widely used in coal char-CO2 gasification. In this work, the production of syngas by using a fluidiz.d bed gasification technique was first investigated and then the effect of the produced syngas on the performance of the solid oxide fuel cell with a configuration of La0.4Sr0.6Co0.2 Fe0.7 Nb0.1O3-δ//La0.8Sr0.2Ga0.83Mg0.17O3-δ//La0.4Sr0.6Co0.2Fe0.7Nb0.1O3-δ（LSCFN//LSGM//LSCFN） was studied. During the syngas production, we found that the volume fraction of CO increased with the increment of gasification temperature, and it reached a maximum value of 88.8%, corresponding to a composition of 0.76% H2, 88.8% CO, and 10.44% CO2, when the ratio of oxygen mass flow rate to that of coal char （Mo2/Mchar） increased to 0.29. In the following utiliz.tion of the produced syngas in solid oxide fuel cells, it was found that the increasing CO volume fraction in the syngas results in a gradual increase of the peak power density of the LSCFN//LSGM//LSCFN cell. The maximum peak power density of 410 mW/cm^2 was achieved for the syngas produced at 0.29 of Mo2/Mchar. In the stability test, the cell voltage decreased by 4% at a constant current density of 0.475 A/cm^2 after 54 h when fueled with the syngas with the composition of 0.76% H2, 88.8% CO, and 10.44% CO2. It reveals that a carbon deposition with the content of 13.66% in the anode is attributed to the cell performance degradation.

关键词： Fluidiz.d bed gasification Syngas Solid oxide fuel cell (SOFC) La0.4Sr0.6Co0.2Fe0.7Nb0.01O3-δ (LSCFN]

Exact Decoding Probability of Random Linear Network Coding for Combinatorial Networks

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Wuhan University Journal of Natural Sciences 2015年第5期20卷 391-396页

作者： LI fang School of Information Xi’an University of Finance and Economics State Key Laboratory of Integrated Services Networks (ISN) Xidian University

Combinatorial networks are widely applied in many practical scenarios. In this paper, we compute the closed-form probability expressions of successful decoding at a sink and at all sinks in the multicast scenario, in which one source sends messages to k destinations through m relays using random linear network coding over a Galois field. The formulation at a （all） sink（s） represents the impact of major parameters, i.e., the siz. of field, the number of relays （and sinks） and provides theoretical groundings to numerical results in the literature. Such condition maps to the receivers＇ capability to decode the original information and its mathematical characteriz.tion is helpful to design the coding. In addition, numerical results show that, under a fixed exact decoding probability, the required field siz. can be minimiz.d.

关键词： random linear network coding successful probability combinatorial networks

A novel ice slurry producing system with vacuum freez.ng

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Journal of Central South University 2017年第3期24卷 736-742页

作者： TANG Yi-fang School of Energy Science and Engineering Central South University Changsha 410083 China Collaborative Innovation Center of Building Energy Conservation & Environmental Control Zhuzhou 412007 China

A novel vacuum ice slurry producing system with jet-pumps was proposed to deal with the problems of high energy consumption and ice *** this novel system,one steam driven by a jet-pump was used to create vacuum in a hermetic vessel where water was sprayed through a noz.le to produce ice slurry,while the other steam was used to provide enough cold energy to make the left vapor in the hermetic vessel *** models of this novel system were established and theoretical simulation on the performance characteristics was also implemented based on the MATLAB *** show that the novel system is feasible and practicable,and the system performance is affected by many factors,such as the temperature of the generators,condensing temperature,evaporation temperature,and the cooling load of the refrigerator *** findings are helpful to improve the performance of ice slurry producing system.

关键词： ice slurry vacuum freez.ng ejector solar energy

A cellphone-based colorimetric multi-channel sensor for water environmental monitoring

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Frontiers of Environmental Science & Engineering 2022年第12期16卷 67-78页

作者： Yunpeng Xing Boyuan Xue Yongshu Lin Xueqi Wu fang fang Peishi Qi Jinsong Guo Xiaohong z.ou State Key Laboratory of Urban Water Resource and Environment School of EnvironmentHarbin Institute of TechnologyHarbin150090China State Key Joint Laboratory of ESPC Center for Sensor Technology of Environment and HealthSchool of EnvironmentTsinghua UniversityBeijing100084China Key Laboratory of the Three Gorges Reservoir Region’s Eco-Environments of MOE Chongqing UniversityChongqing400030China

The development of colorimetric analysis technologies for the commercial cellphone platform has attracted great attention in environmental monitoring due to the low cost,high versatility,easy miniaturiz.tion,and widespread ownership of *** work demonstrates a cellphone-based colorimetric multi-channel sensor for quantifying multiple environmental contaminants simultaneously with high sensitivity and *** improve the sensitivity of the sensor,a delicate optical path system was created by using a diffraction grating to split six white beams transmitting through the multiple colored samples,which allows the cellphone CMOS camera to capture the diffracted light for image *** proposed sensor is a universal colorimetric detection platform for a variety of environmental contaminants with the colorimetry assay in the range of 400–700 *** introducing the diffraction grating for splitting light,the sensitivity was improved by over six folds compared with a system that directly photographed transmitted *** a successful proof-of-concept,the sensor was used to detect turbidity,orthophosphate,ammonia nitrogen and three heavy metals simultaneously with high sensitivity(turbidity:detection limit of 1.3 NTU,linear range of 5–400 NTU;ammonia nitrogen:0.014 mg/L,0.05–5 mg/L;orthophosphate:0.028 mg/L,0.1–10 mg/L;Cr(VI):0.0069 mg/L,0.01–0.5 mg/L;Fe:0.025 mg/L,0.1–2 mg/L;z.:0.032 mg/L,0.05–2 mg/L)and reliability(relative standard deviations of six parallel measurements of 0.37%–1.60%and recoveries of 95.5%–106.0%in surface water).The miniature sensor demonstrated in-field sensing ability in environmental monitoring,which can be extended to point-of-care diagnosis and food safety control.

关键词： Colorimetric analysis Multi-channel sensor Cellphone Water quality indexes Environmental monitoring

Hypersurfaces with Isotropic Para-Blaschke Tensor

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Acta Mathematica Sinica,English Series 2014年第7期30卷 1195-1209页

作者： Jian Bo fang Kun z.ANG Department of Mathematics and Statistics Chuxiong Normal University

Let Mn be an n-dimensional submanifold without umbilical points in the （n ＋ 1）-dimen- sional unit sphere Sn＋l. Four basic invariants of Mn under the Moebius transformation group of Sn＋1 are a 1-form Ф called moebius form, a symmetric （0, 2） tensor A called Blaschke tensor, a symmetric （0, 2） tensor B called Moebius second fundamental form and a positive definite （0, 2） tensor g called Moebius metric. A symmetric （0,2） tensor D = A ＋ μB called para-Blaschke tensor, where μ is constant, is also an Moebius invariant. We call the para-Blaschke tensor is isotropic if there exists a function ,λ such that D = λg. One of the basic questions in Moebius geometry is to classify the hypersurfaces with isotropic para-Blaschke tensor. When λ is not constant, all hypersurfaces with isotropic para-Blaschke tensor are explicitly expressed in this paper.

关键词： Moebius geometry para-Blaschke tensor isotropic

Cerebral palsy in children born after assisted reproductive technology: a meta-analysis

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World Journal of Pediatrics 2021年第4期17卷 364-374页

作者： fang-fang Wang Tao Yu Xiao-Lu Chen Rong Luo De-z.i Mu Department of Pediatrics The First Affiliated Hospital of Zhengzhou UniversityZhengzhouChina Department of Pediatrics West China Second University HospitalSichuan University20 South Renmin Road 3rd SectionWuhou DistrictChengdu 610041China Key Laboratory of Obstetric and Gynecologic and Pediatric Diseases and Birth Defects of Ministry of Education Sichuan UniversityChengduChina

Background Several studies have assessed the association between cerebral palsy(CP)and assisted reproductive technology(ART),but the results remain *** conducted a meta-analysis to evaluate the risk of CP after ART compared with natural conceptions and to examine CP risk separately in ART singletons,multiples and preterm *** Web-based databases(PubMed,Embase,the Cochrane Library,and Web of Science)were searched until November 22,*** which compare CP rates after ART with natural conceptions were *** Newcastle–Ottawa Scale was used to assess the quality of the included *** estimates were extracted and combined using the fixed-effects or random-effects model depending on the heterogeneity *** There were nine studies included in the *** included studies were of moderate or high quality.A significantly higher risk of CP[odds ratio(OR)=2.17,95%confidence interval(CI)1.72–2.74]was found in ART children(n=89,214)compared with naturally conceived children(n=4,160,745).The significantly higher risk decreased when data were restricted to singletons(OR=1.36,95%CI 1.16–1.59)and disappeared when data were restricted to multiples(OR=1.05,95%CI 0.86–1.29)or preterm births(OR=1.53,95%CI 0.66–3.56).Subgroup and sensitivity analyses indicated that the overall results were *** The risk of CP is increased more than two-fold after *** increased risk is largely due to increased rates of multiple birth and preterm delivery in ART children.

关键词： Assisted reproductive technology Cerebral palsy Meta-analysis

Lifting of Outer Actions of Groups

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Acta Mathematica Sinica,English Series 2010年第9期26卷 1693-1700页

作者： fang z.OU He Guo LIU Department of Mathematics Taiyuan Normal University Taiyuan 030012 P. R. China Department of Mathematics Hubei University Wuhan 430062 P. R. China

Let G and N be arbitrary groups. In this paper, we construct an associated group extension εx of N/z.N） by G for any group homomorphism X ： G → Out N, and prove that X can be lifted to a group action, that is, a group homomorphism from G to Aut N, if and only if the extension εx splits. Furthermore we obtain an explicit description for all such lifting homomorphisms and the number of its conjugacy classes, and give an application of the lifting technique of outer actions to the theory of group extensions.

关键词： Outer action group extension lifting

Syntheses and Crystal Structures of z.nc(II) and Nickel(II) Complexes Involving Reduced Nitroxide Radicals

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Chinese Journal of Structural Chemistry 2006年第2期25卷 209-213页

作者： JIANG Kai CHANG Jiu-Li WANG Li-Ya WANG Yu-fang MA Lu-fang College of Chemistry and Environmental Science Henan Normal University Xinxiang 453002 China Department of Chemistry Luoyang Normal University Luoyang 471022 China

Two novel complexes [z.（Him-thz.2（NO3）]·NO3 1 and [Ni（Him-thz.2（NO3）]·NO3 2 （Him-thz.= 2-（2＇-thiaz.le）-4,4,5,5-teramethyl-dihydro-1H-imidaz.lyl-1-hydroxy） have been prepared and structurally characteriz.d by X-ray diffraction method. Both complexes crystalliz. in orthorho- mbic, space group P21 21 2, z.= 2. Crystal data for 1： z.C20H30N8O8S2, Mr = 640.2, a = 13.1630（14）, b = 10.5149（11）, c = 10.6670（11） A°, V= 1476.4（3）A°^3, Dc = 1.440 g/cm^3, μ（MoKa） = 1.028 mm^-1, F（000） = 664, R = 0.0398 and wR = 0.0901 for 2131 observed reflections with I 〉 2σ（I）. Crystal data for 2： NiC20H30N8O8S2, Mr = 633.36, a = 13.1611（7）, b = 10.4833（6）, c = 10.6928（6） .4,, V = 1475.30（14）A°^3, Dc = 1.426 g/cm^3 ,μ（MoKa） = 0.854 mm^-1, F（000） = 660, R = 0.0281 and wR = 0.0797 for 3099 observed reflections with I 〉 2σ（I）. X-ray analysis reveals that the crystal structures consist of [M（Him-thz.2（NO3）]^＋（M = z., Ni） moiety and a NO3^- anion. Both z.nc（Ⅱ） and Nickel（Ⅱ） ions are six-coordinated with distorted octahedral geometries.

关键词： crystal structure nitronyl nitroxide radical z.(Ⅱ) complex Ni(Ⅱ) complex

Fe-N-C core-shell catalysts with single low-spin Fe(Ⅱ)-N_(4)species for oxygen reduction reaction and high-performance proton exchange membrane fuel cells

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Journal of Energy Chemistry 2024年第6期93卷 538-546,I0013页

作者： Yan Wan Linhui Yu Bingxin Yang Caihong Li Chen fang Wei Guo fang-Xing Xiao Yangming Lin Xiamen Key Laboratory of Rare Earth Photoelectric Functional Materials Xiamen Institute of Rare Earth MaterialsHaixi InstituteChinese Academy of SciencesXiamen 361021FujianChina CAS Key Laboratory of Urban Pollutant Conversion Institute of Urban EnvironmentChinese Academy of SciencesXiamen 361021FujianChina Fujian Institute of Research on the Structure of Matter Chinese Academy of SciencesFuzhou 350002FujianChina College of Materials Science and Engineering Fuzhou UniversityNew CampusMinhou 350108FujianChina College of Chemistry and Materials Science Fujian Normal UniversityFuzhou 350117FujianChina

Fe-N-doped carbon materials(Fe-N-C)are promising candidates for oxygen reduction reaction(ORR)relative to Pt-based catalysts in proton exchange membrane fuel cells(PEMFCs).However,the intrinsic contributions of Fe-N_(4)moiety with different chemical/spin states(e.g.D1,D2,D3)to ORR are unclear since various states coexist *** the present work,Fe-N-C core-shell nanocatalyst with single lowspin Fe(Ⅱ)-N_(4)species(D1)is synthesiz.d and identified with ex-situ ultralow temperature Mossbauer spectroscopy(T=1.6 K)that could essentially differentiate various Fe-N_(4)states and invisible Fe-O *** quantifying with CO-pulse chemisorption,site density and turnover frequency of Fe-N-C catalysts reach 2.4×10^(-9)site g^(-1)and 23 e site~(-1)s^(-1)during the ORR,***-wave potential(0.915V_(RHE))of the Fe-N-C catalyst is more positive(approximately 54 mV)than that of Pt/***,we observe that the performance of PEMFCs on Fe-N-C almost achieves the 2025 target of the US Department of Energy by demonstrating a current density of 1.037 A cm^(-2)combined with the peak power density of 0,685 W cm^(-2),suggesting the critical role of Fe(Ⅱ)-N_(4)site(D1).After 500 h of running,PEMFCs still deliver a power density of 1.26 W cm^(-2)at 1.0 bar H_(2)-O_(2),An unexpected rate-determining step is figured out by isotopic labelling experiment and theoretical *** work not only offers valuable insights regarding the intrinsic contribution of Fe-N_(4)with a single spin state to alkaline/acidic ORR,but also provides great opportunities for developing high-performance stable PEMFCs.

关键词： Fuel cells Oxygen reduction reaction Non-platinum group metals(PGMs) Isotopic labelling Active site TOF

Recent progress in plant-derived hard carbon anode materials for sodium-ion batteries:a review

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Rare Metals 2020年第9期39卷 1019-1033页

作者： Peng Yu Wei Tang fang-fang Wu Chun z.ang Hua-Yun Luo Hui Liu z.i-Guo Wang School of Chemistry and Materials Science Hunan Agricultural UniversityChangsha 410128China

Sodium-ion batteries(SIBs)have been considered as a promising alternative to the commercializ.d lithium ion batteries(LIBs)in large-scale energy storage field for its rich reserve in the *** carbon has been expected to the first commercial anode material for *** various of hard carbon materials,plant-derived carbon is prominent because of abundant source,low cost and excellent electrochemical *** review focuses on the recent progress in the development of plantderived hard carbon anodes for *** summariz.d the microstructure and electrochemical performance of hard carbon materials pyrolyz.d from different parts of plants at different *** aims to present a full scope of plant-derived hard carbon anode materials and provide indepth understanding and guideline for the design of highperformance hard carbon for sodium ion anodes.

关键词： Sodium-ion battery Anode material Hard carbon Plant derived Electrochemical performance