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Water-oxidation intermediates enabling electrochemical propylene epoxidation

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Chinese Journal of Structural Chemistry 2024年第5期43卷 1-2页

作者： yang yang jing-Li Luo Xian-Zhu Fu Shenzhen Key Laboratory of Energy Electrocatalytic Materials Guangdong Research Center for Interfacial Engineering of Functional MaterialsCollege of Materials Science and EngineeringShenzhen UniversityShenzhen518055China

In the production of propylene oxide(PO),reliance on hazardous chemical oxidants,such as molecular chlorine(Cl_(2))or peroxides,is a common practice.A promising alternative to current epoxidation methods involves a selective direct propylene epoxidation pathway utilizing water as the oxygen source through water-oxidation *** approach presents a robust substitute for existing epoxidation techniques.

关键词： propylene epoxidation intermediate

Experimental investigation on the anisotropy of friction property for dry and water-saturated rock

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Friction 2024年第9期12卷 2064-2082页

作者： Qing yang Mingming HE Jinrui ZHAO Mingchen DING jing WANG State Key Laboratory of Eco-hydraulics in Northwest Arid Region Xi’an University of TechnologyXi’an 710048China China Communication Construction Company Mechanical and Electrical Engineering Co. Ltd.Beijing 100088China

Friction properties of rock are closely connected with the *** anisotropy of rock friction can provide a valuable assessment for geotechnical and geological *** this study,the rotary friction tests were conducted to analyze the water effect on the friction property and the friction anisotropy of the four types of *** drilling response model(DD-model)was employed to characterize the rotary friction behavior of the *** parameters of this model include the three types of friction parameters:1/ς,μ,and f,where 1/ςandμare constant,and f is a variable.A quantitative method is proposed for assessing the anisotropy of rock *** results of the rotary friction tests indicate that the relation between torque force and thrust force conforms to the *** changes of two friction constants 1/ςandμfrom dry state to water-saturated state suggest that the water effect on the friction strength of the rocks exhibits significant *** friction strength determined by the friction variable f increases first,then decreases,and finally stabilizes with the increasing of *** is an anisotropy index calculated by the proposed *** percentage difference of the average value of AIf between water-saturated and dry states shows the degree of the water effect on the friction anisotropy of the rocks,mudstone(MU)>granite(GR)>fine sandstone(FS)>argillaceous siltstone(AS).The quantitative model is hopefully constructed for characterizing the relation between the anisotropic friction strength of rock and the moisture state in future.

关键词： anisotropy rotary friction test drilling response model(DD-model) effective stress law

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线性位移台直线度高精密外差干涉测量装置

光学精密工程 2018年第7期26卷 1570-1577页

作者：金涛刘景林杨卫乐燕芬侯文玫上海理工大学光电信息与计算机工程学院上海200093 普爱纳米位移技术(上海)有限公司上海201203

直线度测量中往往存在有限的测量范围、精度低和阿贝误差等问题。本文提出了一种高精密直线度外差干涉测量装置,该装置由Koester棱镜、角锥棱镜、1/4波片、楔面棱镜和楔面反射镜构成。楔面棱镜为直线度传感元件,角隅棱镜和楔面反射镜是... 详细信息

直线度测量中往往存在有限的测量范围、精度低和阿贝误差等问题。本文提出了一种高精密直线度外差干涉测量装置,该装置由Koester棱镜、角锥棱镜、1/4波片、楔面棱镜和楔面反射镜构成。楔面棱镜为直线度传感元件,角隅棱镜和楔面反射镜是测量信号的回光元件。双频激光信号进入直线度干涉仪后组成几何空间对称四光路测量信号。四路测量光走过几乎完全相同的路径有效地提高了干涉仪的稳定性,并且使空程误差最小化。使用楔角为1°的楔角棱镜和2π/512细分的相位计,直线度测量分辨力为17.71nm。该方法不需要与行程同长的大反射参考镜,但同样能实现高分辨率,理论和实验证明空间对称测量结构避免了由俯仰,偏转和滚转角引起的阿贝误差的串扰,而且光学元件少,结构简单,方便易用,结果可以直接溯源到米的定义。

关键词：测试计量技术及仪器直线度测量外差激光干涉阿贝误差

From tunnel boring machine to tunnel boring robot: perspectives on intelligent shield machine and its smart operation

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2024年第5期25卷 357-381页

作者： Yakun ZHANG Guofang GONG Huayong yang Jianbin LI Liujie jing State Key Laboratory of Fluid Power and Mechatronic Systems Zhejiang UniversityHangzhou 310058China China Railway Engineering Equipment Group Co. Lid.Zhengzhou 450016China Maha Fluid Power Research Center Purdue UniversityWest LafayetteIN 47905USA

Advances in intelligent shield machines reflect an evolving trend from traditional tunnel boring machines(TBMs)to tunnel boring robots(TBRs).This shift aims to address the challenges encountered by the conventional shield machine industry arising from construction environment and manual *** study presents a systematic review of intelligent shield machine technology,with a particular emphasis on its smart ***,the definition,meaning,contents,and development modes of intelligent shield machines are *** development status of the intelligent shield machine and its smart operation are then *** analyzing the operation process of the shield machine,an autonomous operation framework considering both stand-alone and fleet levels is *** and recommendations are given for achieving autonomous *** study offers insights into the essence and developmental framework of intelligent shield machines to propel the advancement of this technology.

关键词： Intelligent shield machine Tunnel boring machine(TBM) Tunnel boring robot(TBR) Self-driving Autonomous control Shield machine

Superior piezoelectric performance with high operating temperature in bismuth ferrite-based ternary ceramics

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Journal of Materials Science & Technology 2024年第2期169卷 172-181页

作者： Yunyao Huang Leiyang Zhang Ruiyi jing yang yang Vladimir Shur Xiaoyong Wei Li Jin Electronic Materials Research Laboratory Key Laboratory of the Ministry of EducationSchool of Electronic Science and EngineeringXi’an Jiaotong UniversityXi’an 710049China Faculty of Materials and Manufacturing Key Laboratory of Advanced Functional MaterialsEducation Ministry of ChinaBeijing University of TechnologyBeijing 100124China School of Natural Sciences and Mathematics Ural Federal UniversityEkaterinburg620000Russia

Due to the thermal depolarization effect,adequate piezoelectric performance with high operating temperature is regarded to be challenging to accomplish concurrently in piezoceramics for applications in specific piezoelectric *** this work,we synthesized(0.8−x)BiFeO_(3)-x PbTi_(3)-0.2Ba(Zr_(0.25)Ti_(0.75))O_(3)(abbreviated as BFO-x PT-BZT)ternary solid solutions with 0.15≤x≤0.30 by conventional solid-state reaction *** MPB composition with a coexisting state of rhombohedral-tetragonal phases exhibits enhanced electromechanical properties,including Curie temperature of 380℃,large-signal equivalent piezoelectric coefficient d^(∗)_(33)of 395 pm V^(-1),small-signal piezoelectric coefficient d_(33)of 302 pC N^(-1),and electromechanical coupling factor k_(p)of 50.2%,which is comparable to commercial PZT-5A ceramics,indicating potential in high-temperature ***,in-situ X-ray diffraction(XRD)and piezoelectric force microscopic(PFM)techniques demonstrate that multiphase coexistence and complex nanodomains promote piezoelectric response via *** x=0.24 composition exhibits the highest in-situ d_(33)of 577 pC N^(-1)and good temperature stability in 30−280℃,indicating that BZT-modified BFO-PT ceramics are promising candidates for high-temperature piezoelectric devices.

关键词： High-temperature piezoelectrics Morphotropic phase boundary In-situ technique Domain structure BFO

A benchmark-based method for evaluating hyperparameter optimization techniques of neural networks for surface water quality prediction

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Frontiers of Environmental Science & Engineering 2024年第5期18卷 13-27页

作者： Xuan Wang Yan Dong jing yang Zhipeng Liu Jinsuo Lu School of Environmental and Municipal Engineering Xi’an University of Architecture and TechnologyXi’an710055China Shaanxi Key Laboratory of Environmental Engineering Xi’an University of Architecture and TechnologyXi’an710055China State Key Laboratory of Green Building in West China Xi’an University of Architecture and TechnologyXi’an710055China

Neural networks(NNs)have been used extensively in surface water prediction tasks due to computing algorithm improvements and data *** essential step in developing an NN is the hyperparameter *** practice,it is common to manually determine hyperparameters in the studies of NNs in water resources *** may result in considerable randomness and require significant computation time;therefore,hyperparameter optimization(HPO)is *** study adopted five representatives of the HPO techniques in the surface water quality prediction tasks,including the grid sampling(GS),random search(RS),genetic algorithm(GA),Bayesian optimization(BO)based on the Gaussian process(GP),and the tree Parzen estimator(TPE).For the evaluation of these techniques,this study proposed a method:first,the optimal hyperparameter value sets achieved by GS were regarded as the benchmark;then,the other HPO techniques were evaluated and compared with the benchmark in convergence,optimization orientation,and consistency of the optimized *** results indicated that the TPE-based BO algorithm was recommended because it yielded stable convergence,reasonable optimization orientation,and the highest consistency rates with the benchmark *** optimization consistency rates via TPE for the hyperparameters hidden layers,hidden dimension,learning rate,and batch size were 86.7%,73.3%,73.3%,and 80.0%,*** the evaluation of HPO techniques directly based on the prediction performance of the optimized NN in a single HPO test,the proposed benchmark-based HPO evaluation approach is feasible and robust.

关键词： Neural networks Hyperparameter optimization Surface water quality prediction Bayes optimization Genetic algorithm

Polymer: Non-fullerene acceptor heterojunction-based phototransistor for short-wave infrared photodetection

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Nano Research 2024年第4期17卷 3087-3095页

作者： jing Li Weigang Zhu yang Han Yanhou Geng Wenping Hu Key Laboratory of Organic Integrated Circuits of Ministry of Education&Key Laboratory of Molecular Optoelectronic Sciences School of Science&Collaborative Innovation Center of Chemical Science and Engineering(Tianjin)Tianjin UniversityTianjin 300072China Key Laboratory of Organic Integrated Circuits of Ministry of Education&Key Laboratory of Molecular Optoelectronic Sciences School of Materials Science and EngineeringTianjin UniversityTianjin 300072China

It remains full of challenge for extending short-wave infrared(SWIR)spectral response and weak-light detection in the context of broad spectral responses for *** this work,a novel poly(2,5-bis(4-hexyldodecyl)-2,5-dihydro-3,6-di-2-thienyl-pyrrolo[3,4-c]pyrrole-1,4-dione-alt-thiophene)(PDPPT3-HDO):COTIC-4F organic bulk-heterojunction is prepared as active layer for bulk heterojunction ***3-HDO serves as a hole transport material,while COTIC-4F enhances the absorption of SWIR light to 1020 *** a result,smooth and connected PDPPT3-HDO film is fabricated by blade coating method and exhibits high hole mobility up to 2.34 cm^(2)·V^(-1)·s^(-1) with a current on/off ratio of 4.72×10^(5) in organic thin film ***3-HDO:COTIC-4F heterojunction phototransistors exhibit high responsivity of 2680 A·W^(-1) to 900 nm and 815 A·W^(-1) to 1020 nm,with fast response time(rise time~20 ms and fall time~100 ms).The photosensitivity of the heterojunction phototransistor improves as the mass ratio of non-fullerene acceptors increases,resulting in an approximately two orders of magnitude enhancement compared to the bare polymer ***,the phototransistor exhibits decent responsivity even under ultra-weak light power of 43μW·cm^(-2) to 1020 *** work represents a highly effective and general strategy for fabricating efficient and sensitive SWIR light photodetectors.

关键词： photodetection phototransistor organic semiconductor heterojunction non-fullerene acceptor

Chronic administration of triclosan leads to liver fibrosis through hepcidin-ferroportin axis-mediated iron overload

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Journal of Environmental Sciences 2024年第3期137卷 144-154页

作者： jing Liu Lecong Zhang Fang Xu Ping Zhang yang Song College of Eco-Environmental Engineering Guizhou Minzu UniversityGuiyang 550025China The Institute of Karst Wetland Ecology Guizhou Minzu UniversityGuiyang 550025China State Key Laboratory of Environmental Chemistry and Ecotoxicology Research Center for Eco-Environmental SciencesChinese Academy of SciencesBeijing 100085China

Triclosan(TCS)has been manufactured as an antibacterial compound for half a ***,it is widely used in various personal care products;however,its potential adverse effects raise a lot of ***,we create a long-term oral administration mouse model and identify the corresponding hepatotoxicity of *** discover that daily intragastric administration of 10 mg/kg TCS to mice for 12 weeks results in severe hepatic *** study displays that hepatic iron increased 18%,23%and 29%upon oral TCS treatment for4,8 and 12 weeks,*** by hepatic iron variation,splenic and duodenal iron are increased,which indicates systemic iron *** only excessive iron accumulated in the liver,abnormal hepatic malondialdehyde,prostaglandin synthase 2 and glutathione peroxidase 4 are pointed to *** study uncovers that hepcidin expression increases 7%,10%,4%in serum and 2.4-,4.8-,and 2.3-fold on transcriptional levels upon TCS exposure for 4,8 and 12 weeks,*** together,the mice in the TCS-treated group show disordered systemic iron homeostasis via the upregulated hepatic hepcidin-ferroportin ***,both hepatic iron overload(systemic level)and hepatocyte ferroptosis(cellular level)are accused of TCS-induced liver ***■,an iron scavenger,significantly ameliorates TCS-induced liver *** summary,this study confirms the impact of TCS on liver fibrosis;a critical signal pathway is also *** significance of the current study is to prompt us to reevaluate the“pros and cons”of TCS applications.

关键词： Triclosan Iron metabolism Hepcidin Hepatotoxicity Liver fibrosis

In-depth understanding of transport behavior of sulfided nano zerovalent iron/reduced graphene oxide@guar gum slurry: Stability and mobility

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Journal of Environmental Sciences 2024年第10期144卷 1-14页

作者： Yuheng Ma Wenhui You Zijiang yang Zhongyu Ren Qi jing Faculty of Architecture Civil and Transportation EngineeringBeijing University of TechnologyBeijing 100124China

Nanoscale zero-valent iron(NZVI),which has the advantages of small particle size,large specific surface area,and high reactivity,is often injected into contaminated aquifers in the form of ***,the prone to passivation and agglomeration as well as poor stability andmobility of NZVI limit the further application of this technology in ***,sulfided NZVI loaded on reduced graphene oxide(S-NZVI/rGO)and guar gum(GG)with shearthinning properties as stabilizers were used to synthesize S-NZVI/rGO@GG ***,TEM,and FT-IR confirmed that the dispersion and anti-passivation of NZVI were optimized in the coupled *** stability and mobility of the slurry were improved by increasing the GG concentration,enhancing the pH,and decreasing the ionic strength and the presence of Ca^(2+)ions,respectively.A modified advection-dispersion equation(ADE)was used to simulate the transport experiments considering the strain and physicochemical deposition/***,colloidal filtration theory(CFT)demonstrated that Brownian motion plays a dominant role in themigration of S-NZVI/rGO@GG slurry,and the maximummigration distance can be increased by appropriately increasing the injection ***-Derjaguin-Landau-Verwey-Overbeek(XDLVO)theory showed that the excellent stability and migration of S-NZVI/rGO@GG slurry mainly came from the GG spatial *** study has important implications for the field injection of S-NZVI/rGO@GG *** to the injection parameters,the injection range of S-NZVI/rGO@GG slurry is effectively controlled,which lays the foundation for the promotion of application in actual fields.

关键词： S-NZVI rGO Guar gum Transport Stability