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Engineering porous architectures in multicomponent PdCuBP mesoporous nanospheres for electrocatalytic ethanol oxidation

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Nano Research 2021年第9期14卷 3274-3281页

作者： Hao Lv Yaru Wang Dongdong Xu ben liu Jiangsu Key Laboratory of New Power Batteries Jiangsu Collaborative Innovation Center of Biomedical Functional MaterialsSchool oj Chemistry and Materials ScienceNanjing Normal UniversityNanjing 210023China College of Chemistry Sichuan UniversityChengdu 610064China

Porous features of mesoporous metal nanocrystals are critically important for their applications in catalysis,sorption,and biomedicine and ***,precisely engineering porous architectures of mesoporous metals is still highly ***,we report a facile soft-templating strategy to precisely engineer porous architectures of multicomponent PdCuBP mesoporous nanospheres(MSs)by using the surfactants with different amphiphilic *** kinds of MSs with distinct porous architectures,including three-dimensional(3D)opened/interconnected dendritic mesopores(dMSs),one-dimensional(1D)cylindered mesopores(cMSs),and zero-dimensional(0D)spherical mesopores(sMSs),are *** surfactant-templating method is generally extended to regulate elemental compositions of multicomponent *** resultant Pd-based MSs have been evaluated as the electrocatalysts for ethanol oxidation reaction(EOR).Our results show that quaternary PdCuBP dMSs display remarkably high catalytic activity and better stability for electrocatalytic EOR,compared to those of multicomponent MSs with other porous architectures and less elemental *** studies reveal that PdCuBP dMSs combine multiple structural and compositional advantages,which kinetically accelerate the electron/mass transfers and also improve the tolerances to poisoning *** believe that the porous architecture engineering in mesoporous metal electrocatalysts will present a new way to design highly efficient electrocatalysts with desired porous systems and explore their relations towards(electro)catalysis.

关键词： porous architectures multicomponent alloys mesoporous nanosphere surfactant electrocatalysis

非静水压环境对U_(3)O_(8)高压拉曼声子行为的影响

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光谱学与光谱分析 2025年第1期45卷 59-65页

作者：王艺佳吴彬彬刘静仪房雷鸣刘本琼雷力四川大学原子与分子物理研究所四川成都610065 中国工程物理研究院核物理与化学研究所四川绵阳621022

八氧化三铀(U_(3)O_(8))是动力学和热力学最稳定的铀氧化物。研究U_(3)O_(8)的高压相稳定性和高压声子行为对其在核工业、催化剂等领域的应用具有重要参考价值。由于铀原子([Rn]5f^(3)6d^(1)7s^(2))和氧原子([He]2s^(2)2p^(4))核外电子... 详细信息

八氧化三铀(U_(3)O_(8))是动力学和热力学最稳定的铀氧化物。研究U_(3)O_(8)的高压相稳定性和高压声子行为对其在核工业、催化剂等领域的应用具有重要参考价值。由于铀原子([Rn]5f^(3)6d^(1)7s^(2))和氧原子([He]2s^(2)2p^(4))核外电子结构存在显著差异,因此很难通过同步辐射X射线衍射技术探测高压下铀氧化合物中U-O键合的细微变化。然而拉曼光谱对高压下U-O键合变化非常敏感,它能揭示物质在高压下包括键合或者化学计量等方面的重要信息。目前对U_(3)O_(8)高压结构相变的研究通常聚焦于静水压环境,而非静水压环境对U_(3)O_(8)高压相变的影响尚未得到深入研究。该研究基于金刚石对顶砧的高压拉曼散射技术探究了静水压和非静水压环境对正交α-U_(3)O_(8)高压相变与声子行为的影响。研究表明,静水压(8.1 GPa)和非静水压(8.2 GPa)条件下α-U_(3)O_(8)高压相变起始压力很接近。但由于非静水压环境中样品内的微区偏应力较大,因此非静水压环境中U_(3)O_(8)高压相变结束压力(16.4 GPa)比静水压环境中相应压力(18.5 GPa)约低2~3个GPa。同时本文给出了两对比实验中主拉曼模的一阶压力系数与Mode-Grüneisen参数γ。对比分析可知,高压相变前静水压条件下各主模零压下的一阶压力系数绝对值|dω/d P|几乎均大于非静水压条件下的相应值,这表明相变前非静水压环境中各拉曼模对压力响应不明显;一旦高压相变开始,由于较大微区偏应力的存在极大程度增强了铀氧原子外层电子的耦合作用,故相变后非静水压下压力系数绝对值显著增大。零压下B(6)2模的γ值最小,因此对外部扰动有更积极的响应。此外室温加压时A(3)2和A(4)2模(代表沿a轴氧原子的振动)的一阶压力系数通常小于B(4)2和B(6)2模(代表bc面内氧原子的位移),这表明α-U_(3)O_(8)高压相变前a轴比b、c轴更难被压缩。该工作深入探究了静水压和非静水压环境对α-U_(3)O_(8)高压相变的影响,为了解α-U_(3)O_(8)高压相稳定性和晶格动力学行为提供了重要参考。

关键词： U_(3)O_(8) 高压拉曼光谱高压相变非静水压

An effective way to treat the iron-rich acid mine drainage from coal mining in Guizhou’s mountainous areas

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Journal of Mountain Science 2020年第6期17卷 1345-1359页

作者： liu Lei liu ben-hong LI Wei ZHANG Yi College of Architecture and Environment Sichuan UniversityChengdu 610065China

Acid Mine Drainage(AMD)from coal mining is a serious environmental issue which affects water quality,ecology,and the overall landscape of the basin.A large number of coal mine tailings in the mountainous regions of Guizhou Province,China were unattended and iron-rich AMD was directly discharged to the *** discharge leaves the river―yellow‖and heavily *** study tries to find an efficient and economical method for treating iron-rich *** sampled AMD water in two sites:Yangliujie town of Duyun city(hereafter,called Yangliujie),and Xinglong Coal Mine,Duliu town of Guiding county(hereafter,called Xinglong).We performed iron removal laboratory experiment with Cement-bentonite Agent(CBA,80%cement and 20%bentonite)in 500 mL AMD water from Yangliujie,scale-up experiment in 15 L AMD water from both Yangliujie and Xinglong,and engineering application in Xinglong *** experiment results showed the iron removal rate can reach 99.8%and the removal rate depends on the CBA dosage and the treatment *** the scale-up experiment,we found that Fe concentration could be reduced from 587.0 to 0.2 mg/L when adding 20 g/L CBA to the AMD water and aerating for 3 *** sampled water in Xinglong has a very high Fe concentration(Fe 1019.8 mg/L)and the concentration varies with seasons,it is not economical to add the CBA directly to the AMD *** the abundant and cheap limestone resources in Guizhou,we used a twostep treatment method,first we added CaCO3 to raise the pH,and then we took the supernatant liquor and added CBA to the *** was shown that 15 g/L of CBA was a good dosage for iron removal with Fe concentration being reduced from 1019.8 to 0.3 mg/L when CaCO3 was used to raise the *** best treatment realized over 99.9%iron removal,99.2%NH3-N removal,98.9%CODMn removal,and heavy metals in the treated water were reduced to under the limit stipulated in the―Environmental Quality Standards of Surface Water in China‖.Thus in th

关键词： Iron(Fe) pH Acid mine drainage Cement bentonite Mountainous area

A Hybrid Deep Sea Navigation System of LBL/DR Integration Based on UKF and PSO-SVM

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机器人 2015年第5期37卷 614-620页

作者： liu ben liu Kaizhou WANG Yanyan ZHAO Yang CUI Shengguo WANG Xiaohui State Key Laboratory of Robotics Shenyang Institute of Automation Chinese Academy of Sciences Shenyang 110016 China University of Chinese Academy of Sciences Beijing 100049 China

In order to improve the navigation accuracy of human occupied vehicle(HOV)precisely and efficiently,an innovative hybrid approach based on unscented Kalman filter(UKF)and support vector machine(SVM)is proposed to fuse integrated navigation *** is generally equipped with long baseline(LBL)acoustic positioning system and dead reckoning(DR)as an integrated navigation *** is adopted to estimate the state of the dynamic model because of its good performance in filtering nonlinear *** accurate and stable filtering result can be obtained when both LBL and DR are *** the same time,SVM is utilized to train DR information with the result when LBL outrages,and the particle swarm optimization(PSO)algorithm is employed for SVM parameters ***,the integrated navigation system can maintain a good performance when the LBL is *** results with the real navigation data of Jiaolong HOV show that the methodology proposed here is able to meet the needs of HOV application.

关键词： unscented Kalman filter (UKF) particle swarm optimization (PSO) support vector machine (SVM) human occupied vehicle (HOV)

Effect of Swim-Up and Percoll Treatment on Sperm Quality and In vitro Embryo Development in Yak

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Journal of Integrative Agriculture 2013年第12期12卷 2235-2242页

作者： liu ben CUI Yan YU Si-jiu Academic of Veterinary Medicine Gansu Agricultural University Technology and Research Center of Gansu Province for Embryonic Engineering of Bovine and Sheep & Goat

This study was designed to determine the effect of different sperm preparation treatments on yak sperm quality and in vitro embryo ***-thawed semen samples were treated using swim-up or percoll gradient centrifugation *** concentration,progressive motility,recovery of motile sperm,membrane integrity,acrosome and chromatin integrity were scored and compared in recovered samples and *** addition,the effects of two sperm separation treatments on embryos capable of cleavage and in vitro development to the blastocyst stage were ***-up separated sperm showed a higher motility,while the concentration of spermatozoa recovered and percent recovery of motile sperm were higher with percoll gradient centrifugation *** to the optical and electron microscopies,swim-up produced higher percentage of sperm with intact plasma membrane and acrosome than percoll gradient centrifugation ***,there was no difference in the percentage of sperm with intact chromatin between two treatment *** numbers in the blastocysts of two groups were not *** blastocyst rate was similar in both groups,whereas cleavage rate was higher when swim-up was used.

关键词： yak swim-up percoll gradient centrifugation embryo development

Interference suppression for ultra dense network based on compressive sensing framework

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The Journal of China Universities of Posts and Telecommunications 2020年第2期27卷 10-18页

作者： Hou Huanhuan Jiang Jing Lei Ming liu ben School of Communications and Information Engineering Xi'an Universityof Posts and TelecommunicationsXi'an 710061China

Ultra-dense network(UDN)deployment of small cells introduces novel technical challenges,one of which is that the interference levels increase considerably with the network *** paper proposes interference suppression scheme based on compressive sensing(CS)framework for ***,the measurement matrix is designed by exploiting the sparsity of millimeter wave *** technique is employed to transform the high dimension sparse signal into low dimension ***,the interference is canceled in the compressed ***,the stagewise weak orthogonal matching pursuit(SWOMP)algorithm is used to reconstruct the useful signal after interference *** analysis and simulation results demonstrate the effectiveness of the *** results demonstrate that the proposed interference suppression in compressive domain yields performance gains compared to other classical interference suppression *** proposed algorithm can reduce the computational complexity of interference suppression algorithm.

关键词： interference suppression CS signal reconstruction UDN

A universal strategy for fast,scalable,and aqueous synthesis of multicomponent palladium alloy ultrathin nanowires

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Science China Chemistry 2021年第2期64卷 245-252页

作者： Hao Lv Xuwen Guo Lizhi Sun Dongdong Xu ben liu College of Chemistry Sichuan UniversityChengdu 610064China Jiangsu Key Laboratory of New Power Batteries Jiangsu Collaborative Innovation Center of Biomedical Functional MaterialsSchool of Chemistry and Materials ScienceNanjing Normal UniversityNanjing 210023China

Noble metal alloy nanowires(NWs)with ultrathin diameters(2–3 nm)and precisely controllable elemental compositions have attracted dramatically growing attention for(electro)*** numerous achievements in past two decades,noble metal alloy NWs are mostly synthesized with the traditional oil-phase methods that suffer from some undesirable ***,we report a general strategy for fast,scalable,and aqueous synthesis of multicomponent Pd-based alloy ultrathin NWs with an average diameter of 2.6 nm,ranging from bimetallic PdM(PdFe,PdCo,PdNi,PdCu,PdZn,PdRu,PdRh,PdAg,PdCd,PdIr,PdPt,PdAu)and binary PdS/PdP NWs,to trimetallic PdM1M2 NWs(PdAuCu,PdCoNi,PdCuZn,PdCuNi,PdAgCu,PdAuCu,PdRuAg,PdAuRu,and PdPtAu),and to tetrametallic PdM1M2M3 NWs(PdAuAgCu,PdCoCuNi,PdAuCuNi,PdPtAuCu,and PdIrPtAu).The key to the success of this aqueous synthesis is the utilization of N2H4 as the extremely strong reducing agent that directs the synchronous reduction and anisotropic nucleation growth of multicomponent Pd alloy NWs along nanoconfined columnar phase assembled with amphiphilic dioctadecyldimethylammonium ***-resultant Pd-based alloy ultrathin NWs exhibit multiple structural and compositional synergies,which remarkably optimize the removal of poisoning ethoxy intermediates and thus improve electrocatalytic performance towards ethanol oxidation reaction(EOR).Among them,tetrametallic PdAuCuNi alloy ultrathin NWs hold a high EOR activity of 5.14 A mg-1 Pd and a low activation energy of 13.1 kJ mol^-1,both of which are much better than its counterpart catalysts alloyed with less *** work represents an important advance in precise aqueous synthesis of multicomponent noble metal alloy ultrathin NWs as the high-performance electrocatalysts for various targeted applications.

关键词： ultrathin nanowires multicomponent alloys palladium synthetic chemistry ethanol oxidation reaction

Changes in Agricultural System as Farmers Adapt to Economic-Social and Climatic Changes in the Min Upriver Rural Areas in Western Sichuan,Southwestern China

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Journal of Mountain Science 2015年第3期12卷 747-758页

作者： ZHANG Long-jiang TANG Ya liu ben-hong Department of Environment College of Architecture and EnvironmentSichuan University

Rapid economic growth in China has brought about great economic-social changes in rural areas, having considerable impact on the society in economy and environment. With a per capita possession of about 0.08 ha of cropland, Chinese farmers in rural areas adopt various ways in response to these changes in a bit to maintain their livelihood, wherein the agricultural system is facing one more options possible. To understand how rural communities have used different mechanisms to adapt to the economic and natural changes, we joined a survey in dry valleys of the Min upriver area under Maoxian county of western Sichuan province, southwestern China and visited the local people. Changes in the main crop cultivation have shown up an important means to keep up their household income. Farm households start seeking economic growth through diversified cultivating of cereal and economic crops in five lines, namely cereal, apple monoculture, apple and vegetables, plum and vegetables, mixed fruits and vegetables. These new lines mirror farmers' flexibility to cope with today's economic-social and climatic changes. The farming operation has changed all the more from a subsistence on grain to special agricultural products. Economic reforms in the early 1980 s motivated theprogress first in conversion of production from grain to fruits, and the desire to increase family income turned out to be an impetus for the subsequent events. At present, more farmers moving out of the rural areas, uneasy availability of labor force, increased opportunity cost of labors and their wages, increased farm size, and the urgent demand for the agricultural labor force, all these combine into the trend of the agricultural system of China on facing further economic-social reforms and reconstruction of the countryside across China.

关键词： Agricultural system Climate change Farmers Economic impacts Social change MinRiver

Hierarchical Reduced Graphene Oxide-MnO_(2)@Polypyrrole Coaxial Nanotube Composite Hydrogel as a Potential Adsorbent for Cr(Ⅵ)Removal

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Journal of Wuhan University of Technology(Materials Science) 2024年第5期39卷 1287-1293页

作者： liu ben XU Yaowei TONG Yuxing WANG Ziwei liu Zhichang YAN Qunshan JI Jiayou GAO Song LI Shaoping China Tobacco Hubei Industrial Co. LtdWuhan 430040China Hubei Xinye Reconstituted Tobacco Development Co. Ltd.Wuhan 430056China Applied Technology Research of Reconstituted Tobacco Hubei Province Key Laboratory Wuhan 430040China School of Materials Science and Engineering Wuhan Institute of TechnologyWuhan 430205China Hubei Three Gorges Laboratory Yichang 443008China

A hierarchical reduced graphene oxide-MnO_(2)@polypyrrole coaxial nanotube composite hydrogel was prepared via oxidative polymerization of pyrrole in the presence of MnO_(2)nanotubes,followed by the hydrothermal treatment of graphene oxide and MnO_(2)@polypyrrole coaxial *** stable composite hydrogel with a hierarchical network was composed of one-dimensional MnO_(2)@polypyrrole coaxial nanotube and two-dimensional graphene nanosheet and characterized by scanning electron microscope,Fourier transform infrared spectroscopy,X-ray diffraction,Brunauer-Emmett-Teller surface,and X-ray photoelectron spectroscopy *** composite hydrogel can be used as an efficient adsorbent for Cr(Ⅵ)removal due to the synergistic interaction between graphene and MnO_(2)@polypyrrole and the hierarchical structure of the ***,the composite hydrogel is easily separated because of its stable monolith,and it is reusable(76.8%of removal ability remaining after five adsorption-desorption cycles).The simple fabrication and cost-effective separation process together with the excellent absorption performance endow the composite hydrogel with great potential for practical wastewater treatment.

关键词： hydrogel polypyrrole MnO_(2) graphene Cr(Ⅵ)removal