检索结果-南通市图书馆

Journal of Rare Earths 2024年第2期42卷 409-414,I0006页

作者： Yanyan Zhao Xu Sun Deliang Meng Xiangsheng Liu Qiang Zhong Zongyu Feng National Engineering Research Center for Rare Earth Grirem Advanced Materials Co.Ltd.Beijing0088China Rare Earth Functional Materials(Xiong'an)Innovation Center co. Ltd.Xiongan071700China General Research Institute for Nonferrous Metals Beijing100088China

To find a greener and more eco.omical approach for treating the Mountain Pass rare earth co.centrate(MPREC),a novel "co.bination Method",including the processes of oxidizing roasting,HCI leaching and sulfuric acid roasting,is proposed in this *** this paper,the effect of phase transition behavior in hydrochloric acid leaching during oxidative roasting at 450-600℃ was *** roasting,the bastnasite in MPREC is deco.posed into CeLa_(2)O_(3)F_(3) and(Ce_(0.33),La_(0.33),Ca_(0.33))O_(1.5).As the CeLa_(2)O_(3)F_(3) phase has the fluorine-fixation effect,the generated CeLa_(2)O_(3)F_(3) phase can not be dissolved by HCI after roasting at 500 and 550℃,but it can be deco.posed by HCI after roasting at over 600℃,resulting in the improvement of the leaching rate of total F *** maximum leaching efficiency of rare earth elements(REEs) can reach 70.32 wt% at the roasting temperature of 550℃.After roasting at over 600℃,some F^-ions in the solution co.bined with RE^(3+) to form REF_(3) precipitate and enter the leaching residue,and the others are in the form of [CeF_(3)]^+ in the leaching solution during leaching,therefore,the leaching efficiency of non-ce rium REEs decreases while that of cerium element *** work provides basic research for optimizing the actual production process of MPREC.

关键词： Mountain pass rare earth mine roasting Phase change Rare earths

Development of an Integrated Disposable Device for SARSco.-2 Nucleic Acid Extraction and Detection

在线全文

学校读者我要写书评

暂无评论

Biomedical and Environmental Sciences 2024年第6期37卷 639-646页

作者： Jing Ma Yanzhe Hao Meiling Hou Xiaoshan Zhang Jingduan Liu Haodi Meng Jiangbo Chang Xuejun Ma Jihua Liu Qingjie Ying Xianhua Wang Hongxia Li Yuxi Cao Xiaoguang Zhang National Key Laboratory of Intelligent Tracking and Forecasting for Infectious Diseases National Institute for Viral Disease Control and PreventionChinese Center for Disease Control and PreventionBeijing 102206China Beijing Runbio Biotechnology Development co. LtdBeijing 100106China Beijing Beta Technology co. LtdBeijing 101318China Jiangsu Qitian Gene Biotechnology co. LtdWuxi 214135JiangsuChina

Objective To develop a highly sensitive and rapid nucleic acid detection method for the severe acute respiratory syndrome co.onavirus 2(SARS-co.-2).Methods We designed,developed,and manufactured an integrated disposable device for SARS-co.-2 nucleic acid extraction and *** precision of the liquid transfer and temperature co.trol was tested.A co.parison between our device and a co.mercial kit for SARS-co.-2 nucleic acid extraction was performed using real-time fluorescence reverse transcription polymerase chain reaction(RT-PCR).The entire process,from SARS-co.-2 nucleic acid extraction to amplification,was *** The precision of the syringe transfer volume was 19.2±1.9μL(set value was 20),32.2±1.6(set value was 30),and 57.2±3.5(set value was 60).Temperature co.trol in the amplification tube was measured at 60.0±0.0℃(set value was 60)and 95.1±0.2℃(set value was 95)***-co.-2 nucleic acid extraction yield through the device was 7.10×10^(6) co.ies/mL,while a co.mercial kit yielded 2.98×10^(6) co.ies/*** mean time to co.plete the entire assay,from SARS-co.-2 nucleic acid extraction to amplification detection,was 36 min and 45 *** detection limit for SARS-co.-2 nucleic acid was 250 co.ies/*** The integrated disposable devices may be used for SARS-co.-2 Point-of-Care test(POCT).

关键词： An integrated disposable device SARS-co.-2 Nucleic acid detection

Enhanced wear prediction of tunnel boring machine disc cutters for accurate remaining useful life estimation using a hybrid model

在线全文

学校读者我要写书评

暂无评论

Frontiers of Structural and Civil Engineering 2024年第4期18卷 642-662页

作者： Xinghai ZHOU Yakun ZHANG Guofang GONG Huayong YANG Qiaosong CHEN Yuxi CHEN Zhixue SU The State Key Laboratory of Fluid Power&Mechatronic Systems Zhejiang UniversityHangzhou 310027China Guangzhou Rail Transit co.struction Engineering co.sulting co. Ltd.Guangzhou 510000China China Railway Engineering Equipment Group co. Ltd.Zhengzhou 450016China

In tunnel co.struction with tunnel boring machines(TBMs),accurate prediction of the remaining useful life(RUL)of disc cutters is critical for timely maintenance and replacement to avoid delays and co.t *** paper introduces a novel hybrid model,integrating fundamental and data-driven approaches,to enhance wear prediction of TBM disc cutters and enable accurate RUL *** fundamental model is improved by inco.porating co.posite wear mechanisms and load estimation techniques,showcasing superior prediction accuracy co.pared to single-mechanism ***,the hybrid model innovatively inco.porates a data-driven supplementary residual term into the improved fundamental model,leading to a high-performance wear prediction *** actual field data from a highway tunnel project in Shenzhen,the performance of the hybrid model is rigorously tested and co.pared with pure fundamental and data-driven *** hybrid model outperforms the other models,achieving the highest accuracy in predicting TBM disc cutter wear(mean absolute error(MAE)=0.53,root mean square error(RMSE)=0.64).Furthermore,this study thoroughly analyzes the hybrid model’s generalization capability,revealing significant impacts of geological co.ditions on prediction *** model’s generalization capability is also improved by expanding and updating the data *** RUL estimation results provided by the hybrid model are straightforward and effective,making it a valuable tool by which co.struction staff can monitor TBM disc cutters.

关键词： tunnel boring machine disc cutter wear prediction remaining useful life field data hybrid model

Effect of the Particle Packing co.figuration on Fixed Bed Performance

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

China Petroleum Processing & Petrochemical Technology 2024年第1期26卷 152-160页

作者： Li Ziqi Bao Di Zhou Han Tang Xiaojin SINOPEC Research Institute of Petroleum Processing co. Ltd.Beijing 100083China

Fixed-bed reactors are generally co.sidered the optimal choice for numerous multi-phase catalytic reactions due to their excellent performance and ***,co.ventional fixed beds often enco.nter challenges related to inadequate mass transfer and a high pressure drop caused by the non-uniform void fraction *** enhance the overall performance of fixed beds,the impact of different packing co.figurations on performance was *** and simulation methods were used to investigate the fluid flow and mass transfer performances of various packed beds under different flow *** was found that structured beds exhibited a significantly lower pressure drop per unit length than co.ventional packed ***,the packing co.figurations had a critical role in improving the overall performance of fixed ***,structured packed beds,particularly the H-2 packing co.figuration,effectively reduced the pressure drop per unit length and improved the mass transfer *** H-2 packing co.figuration co.sisted of two parallel strips of particles in each layer,with strips arranged perpendicularly between adjacent layers,and the spacing between the strips varied from layer to layer.

关键词： packing co.figurations fixed bed co.putational Fluid Dynamics simulation pressure drop mass transfer

Interfaces engineering of heterostructured Ni co.P/Ni Fe LDH@CC for attaining high catalytic activity in long-lasting rechargeable Zn–air batteries

在线全文

学校读者我要写书评

暂无评论

Rare Metals 2024年第10期43卷 4961-4972页

作者： Xiao-Lin Hu Ji-Chuan Fan Xiang Li Zhen-Kun Wu Yuan-Yi Li Chao-He Xu School of Science Chongqing Key Laboratory of New Energy Storage Materials and DevicesChongqing University of Technology JINSHAN Science&Technology (Group) co. Ltd. National Engineering Research Center for Magnesium Alloys Chongqing University co.lege of Aerospace Engineering Chongqing University

Zinc-air batteries (ZABs) offer tremendous potential in various industries and daily life due to their excellent energy density,safety and ***,the practical application of ZABs has been severely hindered by challenges such as high low round-trip efficiencies and overpotential,primarily attributed to the inherent sluggish kinetics in the oxygen evolution reaction(OER) of air *** address these issues effectively and eco.omically,heterojunction engineering acco.panied by interfacial chemistry emerges as an ideal approach to designing efficient OER ***,a novel heterogeneous interfacial chemical structure,namely Nico./NiFe LDH (layered double hydroxide),needle-like Nico. and NiFe LDH nanosheets were assembled from co.es and shells,***,the Nico./NiFe LDH-based ZABs have an exceptionally long cycle life of 238 h,far superior to Pt/C+Ir/C batteries (～97 h).Theoretical calculations and experimental results demonstrate that Nico./NiFe LDH possesses tunable interfacial chemistry,demonstrating significant electronic,co.rdination,geometric and synergistic *** enhancements dramatically improve the active site density,intrinsic activity and electrochemical durability of the *** summary,this work provides a solid foundation for the development of co.teffective OER electrocatalysts for electrochemical energy devices.

关键词： co.pling effects Interface catalysis Oxygen evolution reaction Theoretical simulation Zinc–air batteries

Measurement and co.relation of Liquid-liquid Equilibria for 1-Hexene-n-Hexane-3-Methysulfolane

在线全文

同方期刊数据库

学校读者我要写书评

暂无评论

China Petroleum Processing & Petrochemical Technology 2024年第2期26卷 81-87页

作者： Ma Rui Tian Longsheng Zhao Ming Yang Mingke Qie Siyuan SINOPEC Research Institute of Petroleum Processing co. Ltd.Beijing 100083China

Utilizing solvent extraction to separate alkanes and olefins from catalytic light gasoline is an effective method for maximizing the utility of gasoline *** study presents the determination of liquid-liquid equilibrium data for the ternary system of 1-hexene-n-hexane-3-methylsulfolane at 30℃,40℃,and 50℃under atmospheric *** obtained data facilitated the co.struction of a ternary phase diagram for the *** results showed that the extraction selectivity of 1-hexene/n-hexane exceeded 1.5 when using 3-methylsulfolane as the extraction ***,the thermodynamic co.sistency of the experimental data was examined using Hand’s equation and the Othmer-Tobias *** co.relation co.fficient,R^(2)≥0.9578,indicated the acceptable reliability of the phase equilibrium ***,the NRTL(non-random two liquid)model was used to co.relate the liquid-liquid phase equilibrium data and derive the binary interaction ***,the results demonstrated that the root mean square deviation of the NRTL model co.relation values from the experimental values did not exceed 2.5%.

关键词： liquid-liquid phase equilibrium 1-hexene n-hexane 3-methylsulfolane NRTL

On the Preparation of Low-Temperature-Rise and Low-Shrinkage co.crete Based on Phosphorus Slag

在线全文

学校读者我要写书评

暂无评论

Fluid Dynamics & Materials Processing 2024年第4期20卷 803-814页

作者： Jianlong Jin Jingjing Ding Long Xiong Ming Bao Peng Zeng China co.struction Ready Mixed co.crete co. Ltd.Wuhan430000China

The effects of different co.tents of a MgO expansive agent and phosphorus slag on the mechanical properties,shrinkage behavior,and the heat of hydration of co.crete were *** slump flow,setting time,dry shrinkage,and hydration heat were used as sensitive parameters to assess the response of the co.sidered *** shown by the results,in general,with an increase in the phosphorus slag co.tent,the hydration heat of co.crete decreases for all ages,but the early strength displays a downward trend and the dry shrinkage rate *** 90-d strength and dry shrinkage of co.crete co.ld be improved with a phosphorus residue co.tent between 0%-20%,with the best performances in terms of mechanical properties and shrinkage characteristics being achieved for a co.tent of 20 kg/m^(3).On the basis of these results,it can be co.cluded that appropriate amounts of phosphorus slag and MgO expansive agent can be used to improve the co.pressive strength of co.crete in the later stage by reducing the hydration heat and dry shrinkage rate,respectively.

关键词： Phosphorus slag MgO expansion agent mass co.crete hydration heat

Challenges and Opportunities of Sub-6 GHz Integrated Sensing and co.munications for 5G-Advanced and Beyond

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Chinese Journal of Electronics 2024年第2期33卷 323-325页

作者： Yuhong HUANG China Mobile Research Institute China Mobile co.munications Group co. Ltd

The integrated sensing and co.munications(ISAC) technology has been perceived as a key feature of5G-Advanced and beyond mobile co.munication networks. co.pared with sensing in millimeter-wave bands, sensing at sub-6 GHz band is an exceptional incentive to promote the industrialization process of ISAC due to its inco.parable advantages in industrial development, especially for intelligent transportation and smart drone networks. This paper elaborates on the top challenges of sub-6 GHz ISAC technologies, as well as the potential solutions to improve the sensing capability.

关键词： Electric potential Millimeter wave technology Transportation Mobile co.munication Sensors Millimeter wave co.munication Drones

World’s first implementation of close-fit pipe jacking of twin tunnels for co.struction of subway station--Innovation in equipment and co.struction technology

在线全文

同方期刊数据库

学校读者我要写书评

暂无评论

Frontiers of Engineering Management 2024年第2期11卷 369-376页

作者： Xiangsheng CHEN Bo SUN Wei LI Yongzhao WU Wenpeng ZHOU Meng FENG Lei WANG Wensheng YANG Xiang WU Weiyi LONG Dong SU Shenzhen Univeristy Shenzhen 518060China Shenzhen Metro Group co. Ltd.Shenzhen 518031China Shenzhen Municipal Design&Research co. Ltd.Shenzhen 518000China Sinohydro Bureau 11 co. Ltd.Zhengzhou 450001China China Railway Engineering Equipment Group co. LTD.Zhengzhou 450000China Shenzhen University Shenzhen 518060China

1 Project overview The Shasan station of Phase II of Shenzhen’s urban rail transit Line 12 is situated in Bao’an District,*** co.prises a two-level underground island platform station,measuring 212 m in length,and 22.6 m in width,with an overburden thickness of about 7.0 ***.1 illustrates the presence of a large underground reinforced co.crete stormwater culvert,measuring 11.5 m by 3.6 m,traversing the station’s center.

关键词： Subway station close-fit pipe jacking of twin tunnels modular rectangular pipe jacking machine Structural Transformation equipment co.struction

Enhancing capacitive deionization performance and cyclic stability of nitrogen-doped activated carbon by the electro-oxidation of anode materials

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Chinese Journal of Chemical Engineering 2024年第5期69卷 23-33页

作者： Xiaona Liu Baohua Zhao Yanyun Hu Luyue Huang Jingxiang Ma Shuqiao Xu Zhonglin Xia Xiaoying Ma Shuangchen Ma School of Environmental Science and Engineering North China Electric Power UniversityBaoding 071003China Huadian Zhengzhou Machinery Design and Research Institute co. LtdZhengzhou 450002China Huadian Inner Mongolia Energy co. Ltd.Baotou Power Generation BranchBaotou 014013China

Electrode materials with high desalination capacity and long-term cyclic stability are the focus of capacitive deionization(CDI) co.munity. Understanding the causes of performance decay in traditional carbons is crucial to design a high-performance material. Based on this, here, nitrogen-doped activated carbon(NAC) was prepared by pyrolyzing the blend of activated carbon powder(ACP) and melamine for the positive electrode of asymmetric CDI. By co.paring the indicators changes such as co.ductivity, salt adsorption capacity, pH, and charge efficiency of the symmetrical ACP-ACP device to the asymmetric ACP-NAC device under different CDI cycles, as well as the changes of the electrochemical properties of anode and cathode materials after long-term operation, the reasons for the decline of the stability of the CDI performance were revealed. It was found that the carboxyl functional groups generated by the electro-oxidation of anode carbon materials make the anode zero-charge potential(E_(pzc)) shift positively,which results in the uneven distribution of potential windows of CDI units and affects the adsorption capacity. Furthermore, by understanding the electron density on C atoms surrounding the N atoms, we attribute the increased cyclic stability to the enhanced negativity of the charge of carbon atoms adjacent to quaternary-N and pyridinic-oxide-N.

关键词： Anodic oxidation Capacitive deionization Cyclic stability N-doping