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Frontiers of Environmental Science & Engineering 2024年第4期18卷 91-102页

作者： Zhihao Xian Jun Yan Jingyi dai Hao Wu Xin Zhang Wenbo nie Fucheng Guo Yi Chen Key Laboratory of the Three Gorges Reservoir Region’s Eco-Environment(Ministry of Education) Chongqing UniversityChongqing 400044China College of Environment and Ecology Chongqing UniversityChongqing 400044China

Constructed wetlands(CWs)are widely used to treat secondary ***,simultaneously removing ammonia(nH_(4)^(+)-n)and nitrate(nO_(3)^(–)–n)is challenging because of insufficient oxygen and carbon *** this study,a novel composite material(MPCM)comprising MnO_(2) and polycaprolactone was developed as a substrate for CWs to enhance the synchronous removal of nH_(4)^(+)–n and nO_(3)^(–)–*** CWs with a higher MPCM content(H-CW),lower MPCM content(LCW),and controlled CW(C-CW)exhibited average nH_(4)^(+)–n removal efficiencies of 75.69%,70.49%,and 52.40%,*** 15n isotope tracking technique showed that nH_(4)^(+)–n removal was attributed to anaerobic ammonia oxidation mediated by MnO2 reduction(Mnammox),which accounted for 17.16%–27.24%of the nH_(4)^(+)–n removal in the composite material layers(0–20 cm)of the H-CW and *** richness of ammonia oxidizers in the upper layers(40–50 cm)of the HCW and L-CW further facilitated nH_(4)^(+)–n ***,the average total nitrogen(Tn)removal efficiencies of the H-CW and L-CW were 1.99 and 1.59 times that of C-CW,respectively,owing to enhanced denitrification by ***,n_(2)O emissions were reduced by 81.31%and 70.83%in the H-CW and L-CW,*** study provides an effective approach for improving nitrogen removal and reducing n2O emissions during the treatment of secondary effluent by CWs.

关键词： Constructed wetland nitrogen removal Manganese redox Polycaprolactone nitrous oxide

基于协同优化策略和人工蜂群算法的轨道电路邻线干扰防护研究

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中国铁道科学 2024年第1期45卷 178-189页

作者：代萌中国铁路济南局集团有限公司济南电务段山东济南250001

高速铁路车站运营场景复杂,易引发轨道电路邻线干扰,造成信号误解码和误显示,影响列车安全高效运行。基于空间耦合和传导耦合原理,根据高速铁路轨道电路特点和结构,分别建立传输线路阻抗平衡和不平衡条件下的复杂场景邻线干扰计算模型;... 详细信息

高速铁路车站运营场景复杂,易引发轨道电路邻线干扰,造成信号误解码和误显示,影响列车安全高效运行。基于空间耦合和传导耦合原理,根据高速铁路轨道电路特点和结构,分别建立传输线路阻抗平衡和不平衡条件下的复杂场景邻线干扰计算模型;考虑机车动态运行条件,完成最不利情况下邻线干扰量值的定量计算,并利用AnSYS平台完成计算结果的有限元仿真验证;针对邻线干扰还受到发送电平等级、补偿电容数量和容值、线路并行长度、道床电阻、分路电阻、线路间距等参数叠加和相互制约的影响,采用人工蜂群(Artificial Bee Colony,ABC)智能算法,提出基于多参数协同优化策略的邻线干扰防护对策,给出各参数相应最优取值及其对信干比(Signal-to-Interference Ratio,SIR)影响重要度。结果表明:邻线干扰量值超过车载机车信号灵敏度将导致解码错误;应用提出的防护对策对现场邻线干扰工程案例中线路并行长度和发送电平等参数进行优化,SIR可提升14.6 dB。研究结论可用于高速铁路轨道电路配置及优化实践,为防护邻线干扰提供工程参考和分析验证。

关键词：高速铁路轨道电路邻线干扰人工蜂群算法干扰防护协同优化

Controlling Three-Step and Five-Step Spin Transitions by Polymorphism in an Fe^(Ⅲ) Spin Crossover Complex

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Chinese Journal of Chemistry 2024年第8期42卷 879-886页

作者： Yingying Wu Shuang Peng Ziyi Zhang Yue Gao Guangyan Xu Jingwei dai Zhao-Yang Li Masahiro Yamashita School of Materials Science and Engineering Nankai University38 Tongyan RoadHaihe Educational ParkTianjin300350 China State Key Laboratory of Medicinal Chemical Biology Nankai UniversityTianjin300071 China Department of Chemistry Graduate School of ScienceTohoku UniversitySendai980-8578 Japan

Comprehensive Summary,Regulating spin crossover(SCO)behavior,especially controlling the spin transition steps,is an important scientific issue,mainly because people aim to control spin bistability and ***,SCO bistability can be regulated by changing the ligand-modifying species,non-coordinated anions,guest molecules,and metal-ion ***,the control of multistability is extremely challenging,especially in Fe(III)SCO ***,we report that[FeIII(H-5-Br-thsa)(5-Br-thsa)]·H2O(5-Br-thsa=(5-bromo-2-hydroxybenzylidene)hydrazinecarbothioamide),a compound we have reported before,exists in two polymorphic forms:polymorph 1 exhibits three-step SCO,and polymorph 2 shows five-step SCO,with multi-step SCO behavior effectively regulated by *** to single-crystal and powder X-ray diffractometry,polymorphs 1 and 2 crystallize in different space groups during their spin transitions,with two-step symmetry breaking observed(Pbcn→Pnc2→Pbcn for polymorph 1;P21/n→Pn→P21/n for polymorph 2).We realized that the behavior of these two polymorphs depends significantly on the structure,including(i)the average Fe—n bond distance,(ii)deformation of octahedral FeIII atoms,and(iii)distinct crystal packing,which account for the large differences observed in magnetic properties.

关键词： Spin crossover Multi-step spin transition Symmetry breaking Polymorphism Magnetic property

Theoretical insights into the structures and fundamental properties of pnictogen nitrides

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Chinese Physics B 2024年第9期33卷 474-479页

作者： Jingjing Wang Panlong Kong Dingmei Zhang Defang Gao Zaifu Jiang Wei dai School of Mathematics and Physics Jingchu University of TechnologyJingmen 448000China

Recent experimental advancements reported a chemical reaction between antimony and nitrogen under high temperature and high pressure,yielding crystalline antimony nitride(Sb_(3)n_(5))with an orthorhombic *** by this statement,we calculate the stability,elastic properties,electronic properties and energy density of the Cmc2_(1) structure for pnictogen nitrides X_(3)n_(5)(X=P,As,Sb,and Bi)using first-principles calculations combined with particle swarm optimization *** of formation enthalpies,elastic constants and phonon spectra show that P_(3)n_(5),As_(3)n_(5) and Sb_(3)n_(5) are thermodynamically,mechanically and kinetically stable at 35 GPa,whereas Bi_(3)n_(5) is mechanically and kinetically stable but thermodynamically *** computed electronic density of states shows strong covalent bonding between the n atoms and the phosphorus group atoms in the four compounds,confirmed by the calculated electronic localization *** also calculate the energy densities for Sb_(3)n_(5) and find it to be a potentially high-energy-density material.

关键词： pnictogen nitrides structural stability electronic property energy density

Molten metal-organic complex to synthesize versatile ultrathin nonlayered oxides

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nano Research 2024年第4期17卷 3147-3155页

作者： Kaisi Liu Jiabin Wu Qun Li Hongrun Jin Yongxin Luo Bei Qi Simin dai Jianquan Zhao Liang Huang Jun Zhou Hubei Key Laboratory of Biomass Fibers and Eco-Dyeing&Finishing Wuhan Textile UniversityWuhan 430200China Wuhan national Laboratory for Optoelectronics School of Optical and Electronic InformationHuazhong University of Science and TechnologyWuhan 430074China Analytical and Testing Center Huazhong University of Science and TechnologyWuhan 430074China

Two-dimensional(2D)materials have attracted a great deal of research interest because of their unique electrical,magnetic,optical,mechanical,and catalytic properties for various *** date,however,it is still difficult to fabricate most functional oxides as 2D materials unless they have a layered ***,we report a one-step universal strategy for preparing versatile non-layered oxide nanosheets by directly annealing the mixture of metal nitrate and dimethyl imidazole(2-MI).The 2-MI plays the key role for 2D oxides since 2-MI owns a very low molten point and sublimation temperature,in which its molten liquid can coordinate with metal ions,forming a metal-organic framework,and easily puffing by its gas molecules.A total of 17 materials were prepared by this strategy,including non-layered metal oxide nanosheets as well as metal/metal oxide loaded nitrogen-doped carbon *** as-prepared cobalt particle-loaded nitrogen-doped carbon nanosheets(Co@n/C)exhibit remarkable bifunctional oxygen reduction reaction(ORR)and oxygen evolution reaction(OER)electrocatalytic activity and ***,the Zn-air battery utilizing a Co@n/C catalyst exhibits high power density of 174.3 mW·cm^(-2).This facile strategy opens up a new way for large-scale synthesis of 2D oxides that holds great potential to push 2D oxides for practical applications.

关键词： non-layered oxide nanosheet metal/metal oxide@n/C oxygen evolution reaction(OER) oxygen reduction reaction(ORR) Zn-air battery

Oxidation resistant low-alloyed Ti alloys with good ductility

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Rare Metals 2024年第8期43卷 3921-3936页

作者： Meng Li Zhang-Zhi Shi Jun-Yi Xu Fu-Zhi dai Xiang-Min Li Zi-Lin Li Lu-ning Wang Beijing Advanced Innovation Center for Materials Genome Engineering State Key Laboratory for Advance Metals and MaterialsSchool of Materials Science and EngineeringUniversity of Science and Technology BeijingBeijingBeijing 100083China Institute of Materials Intelligent Technology Liaoning Academy of MaterialsShenyang 110004China

Oxidation resistance enhancement of pure Ti often comes at the cost of reduced ductility,which is frequently the problem through alloying with sole Al,Si,W,Mo and *** overcome the short coming of single element alloying,this paper proposes a multi-element low-alloying strategy to take advantage of synergistic effects and resolve the conflict between oxidation resistance and *** demonstrates that the addition of a small quantity of Ta(0.51wt%)can boost both oxidation resistance and ductility in comparison to pure ***,the combined addition of a small amount(0.54 wt%)of Ta,nb and Si not only preserves good ductility of pure Ti,but also reduces mass gains to 14%-67%of pure Ti during 100 h oxidation at 650-850℃in *** indicates even better oxidation resistance than that obtained through the use of Ta,nb,or nb+Ta *** Ta+nb+Si alloying creates an oxide layer that is less porous and more resistant to stratification and ***,a 3-μm n-rich layer can form in the Ti substrate beneath the oxide scale,in which phase transformation generates coherent Ti_(2)n with(0001)_(Ti)as the habit plane,with n atoms prefers to diffuse along■than along[0001]_(Ti).The completely transformed Ti_(2)n region or partially transformed Ti+Ti_(2)n region can effectively impede oxygen ***,the multielement low-alloying strategy is promising for enhancing both oxidation resistance and mechanical properties of metallic materials in the future.

关键词： Ti alloys Multi-element Co-alloying Oxidation resistance Mechanical properties

Catalytic upgrading biomass-derived ethanol and acetic acid into C4 chemicals

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Science China Chemistry 2024年

作者： Tingting Yan Mengting Zhang Runzhi Yuan Weili dai College of Science Civil Aviation University of China School of Materials Science and Engineering & national Institute for Advanced Materials Nankai University

Synthesis of value-added chemicals from biomass is an essential strategy to mitigate the global dependency on fossil resources and achieve the aim of carbon neutrality. Thereinto, ethanol and acetic acid are crucial biomass-derived platform ***, catalytic upgrading ethanol and acetic acid into C4 energy-intensive fuels and chemicals via the elongation of carbon backbone has received widespread attention. The primary focus of this review is to systematically describe the recent breakthrough in the conversion of ethanol or acetic acid to C4 chemicals including 1,3-butadiene, n-butenes, isobutene or *** attentions will be given to heterogeneous catalyst design strategies, reaction parameters on the catalytic performance along with the relevant mechanism investigations, as well as their future challenges and opportunities. The present review will provide the detailed insights into the synthesis of C4 chemicals from biomass-derived ethanol and acetic acid and shed a light on the development of highly efficient catalysts.

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Multiple-dimensioned defect engineering for graphite felt electrode of vanadium redox flow battery

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Carbon Energy 2024年第2期6卷 143-153页

作者： Yingqiao Jiang Yinhui Wang Gang Cheng Yuehua Li Lei dai Jing Zhu Wei Meng Jingyu Xi Ling Wang Zhangxing He School of Chemical Engineering North China University of Science and TechnologyTangshanChina Tsinghua Shenzhen International Graduate School Institute of Materials ResearchTsinghua UniversityShenzhenChina

The scarcity of wettability,insufficient active sites,and low surface area of graphite felt(GF)have long been suppressing the performance of vanadium redox flow batteries(VRFBs).Herein,an ultra-homogeneous multipledimensioned defect,including nano-scale etching and atomic-scale n,O codoping,was used to modify GF by the molten salt ***_(4)Cl and KClO_(3) were added simultaneously to the system to obtain porous n/O co-doped electrode(GF/On),where KClO_(3) was used to ultra-homogeneously etch,and O-functionalize electrode,and nH4Cl was used as n dopant,***/On presents better electrochemical catalysis for VO_(2)+/VO_(2)+ and V3+/V2+ reactions than only O-functionalized electrodes(GF/O)and *** enhanced electrochemical properties are attributed to an increase in active sites,surface area,and wettability,as well as the synergistic effect of n and O,which is also supported by the density functional theory ***,the cell using GF/On shows higher discharge capacity,energy efficiency,and stability for cycling performance than the pristine cell at 140 mA cm^(−2) for 200 ***,the energy efficiency of the modified cell is increased by 9.7% from 55.2% for the pristine cell at 260 mA cm^(−2).Such an ultra-homogeneous etching with n and O co-doping through“boiling”molten salt medium provides an effective and practical application potential way to prepare superior electrodes for VRFB.

关键词： graphite felt molten salt n O co-doping ultra-homogeneous etching vanadium redox flow battery

Ultra‑Efficient and Cost‑Effective Platinum nanomembrane Electrocatalyst for Sustainable Hydrogen Production

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nano-Micro Letters 2024年第6期16卷 95-110页

作者： Xiang Gao Shicheng dai Yun Teng Qing Wang Zhibo Zhang Ziyin Yang Minhyuk Park Hang Wang Zhe Jia Yunjiang Wang Yong Yang Department of Mechanical Engineering College of EngineeringCity University of Hong KongTat Chee AvenueKowloon TongKowloonHong KongPeople’s Republic of China State Key Laboratory of nonlinear Mechanics Institute of MechanicsChinese Academy of SciencesBeijingPeople’s Republic of China School of Engineering Science University of Chinese Academy of SciencesBeijingPeople’s Republic of China Laboratory for Microstructures Institute of MaterialsShanghai UniversityShanghaiPeople’s Republic of China School of Materials Science and Engineering Jiangsu Key Laboratory for Advanced Metallic MaterialsSoutheast UniversityNanjingPeople’s Republic of China Department of Materials Science and Engineering College of EngineeringCity University of Hong KongTat Chee AvenueKowloon TongKowloonHong KongPeople’s Republic of China

Hydrogen production through hydrogen evolution reaction(HER)offers a promising solution to combat climate change by replacing fossil fuels with clean energy ***,the widespread adoption of efficient electrocatalysts,such as platinum(Pt),has been hindered by their high *** this study,we developed an easy-to-implement method to create ultrathin Pt nanomembranes,which catalyze HER at a cost significantly lower than commercial Pt/C and comparable to non-noble metal *** Pt nanomembranes consist of highly distorted Pt nanocrystals and exhibit a heterogeneous elastic strain field,a characteristic rarely seen in conventional *** unique feature results in significantly higher electrocatalytic efficiency than various forms of Pt electrocatalysts,including Pt/C,Pt foils,and numerous Pt singleatom or single-cluster *** research offers a promising approach to develop highly efficient and cost-effective low-dimensional electrocatalysts for sustainable hydrogen production,potentially addressing the challenges posed by the climate crisis.

关键词： Platinum Hydrogen evolution reaction Lattice distortion Heterogeneous strain

Development and validation of a prediction model for early screening of people at high risk for colorectal cancer

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World Journal of Gastroenterology 2024年第5期30卷 450-461页

作者： Ling-Li Xu Yi Lin Li-Yuan Han Yue Wang Jian-Jiong Li Xiao-Yu dai Department of General Surgery Ningbo No.2 HospitalNingbo 315000Zhejiang ProvinceChina Center for Health Economics Faculty of Humanities and Social SciencesUniversity of NottinghamNingbo 315100Zhejiang ProvinceChina Department of Global Health Ningbo Institute of Life and Health IndustryUniversity of Chinese Academy of SciencesNingbo 315000Zhejiang ProvinceChina School of Public Health Medical College of Soochow UniversitySuzhou 215123Jiangsu ProvinceChina

BACKGROUnD Colorectal cancer(CRC)is a serious threat *** early screening is suggested to be the most effective method to prevent and control CRC,the current situation of early screening for CRC is still not *** China,the incidence of CRC in the Yangtze River Delta region is increasing dramatically,but few studies have been ***,it is necessary to develop a simple and efficient early screening model for *** To develop and validate an early-screening nomogram model to identify individuals at high risk of *** Data of 64448 participants obtained from ningbo Hospital,China between 2014 and 2017 were retrospectively *** cohort comprised 64448 individuals,of which,530 were excluded due to missing or incorrect *** 63918,7607(11.9%)individuals were considered to be high risk for CRC,and 56311(88.1%)were *** participants were randomly allocated to a training set(44743)or validation set(19175).The discriminatory ability,predictive accuracy,and clinical utility of the model were evaluated by constructing and analyzing receiver operating characteristic(ROC)curves and calibration curves and by decision curve ***,the model was validated internally using a bootstrap resampling *** Seven variables,including demographic,lifestyle,and family history information,were *** logistic regression analysis revealed that age[odds ratio(OR):1.03,95%confidence interval(CI):1.02-1.03,Pndex(BMI)(OR:1.07,95%CI:1.06-1.08,Pnce(WC)(OR:1.03,95%CI:1.02-1.03 Pnd family history(OR:4.28,95%CI:4.04-4.54,Pnificant predictors of high-risk *** lifestyle was a protective factor,whereas family history was the most significant risk *** area under the curve was 0.734(95%CI:0.723-0.745)for the final validation set ROC curve and 0.735(95%CI:0.728-0.742)for the training s

关键词： Colorectal cancer Early screening model High-risk population nomogram model Questionnaire survey Dietary habit Living habit