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高应力软岩隧道二次衬砌合理支护时机分析研究

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建筑技术开发 2024年第9期51卷 83-85页

作者：徐志平中铁第一勘察设计院集团有限公司西安710043

以兰渝铁路某隧道为研究对象,考虑炭质板岩地层的蠕变特性,基于广义西元模型,对隧道施工过程进行三维数值模拟,研究了不同支护时机下初期支护、二次衬砌的受力变形规律。研究结果表明:(1)提前施作二次衬砌,能够和初期支护构成叠合支护体... 详细信息

以兰渝铁路某隧道为研究对象,考虑炭质板岩地层的蠕变特性,基于广义西元模型,对隧道施工过程进行三维数值模拟,研究了不同支护时机下初期支护、二次衬砌的受力变形规律。研究结果表明:(1)提前施作二次衬砌,能够和初期支护构成叠合支护体系,有效约束软岩变形,减小变形速率,施作时间越早,围岩变形控制效果越好;(2)初期支护和二次衬砌的应力支护时机相关。二次衬砌施作时间越早,越能够改善初期支护的受力状态,减小初期支护应力,同时分担的围岩形变压力越大,二次衬砌应力越大。

关键词：软岩隧道高地应力二次衬砌粘弹塑性数值分析

19种杀虫剂对藜麦甜菜筒喙象的室内防治试验

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湖北农业科学 2024年第4期63卷 67-72页

作者：许志萍赵晓军邢鲲赵飞山西农业大学植物保护学院山西太谷030801

选用19种杀虫剂,以硅藻土及黄绵土作为农药载体,开展了藜麦(Chenopodium quinoa)甜菜筒喙象(Lixus subtilis Boheman)的室内防治试验。结果表明,以黄绵土或硅藻土为载体时,40%毒死蜱乳油和40%辛硫磷乳油都表现出了较高的速效性和持效性,... 详细信息

选用19种杀虫剂,以硅藻土及黄绵土作为农药载体,开展了藜麦(Chenopodium quinoa)甜菜筒喙象(Lixus subtilis Boheman)的室内防治试验。结果表明,以黄绵土或硅藻土为载体时,40%毒死蜱乳油和40%辛硫磷乳油都表现出了较高的速效性和持效性,7 d后防治效果均达100%,推荐生产使用。以硅藻土为载体时,可显著提高5%啶虫脒乳油、3.2%高氯·甲维盐微乳剂、5%甲氨基阿维菌素苯甲酸盐悬浮剂和20%呋虫胺可溶粒剂的防治效果,药后7 d防治效果分别为100.0%、100.0%、73.3%和95.8%,可有效防治藜麦甜菜筒喙象,推荐在生产中采用杀虫剂与硅藻土混合施用的方式施药。

关键词：藜麦(Chenopodium quinoa) 甜菜筒喙象(Lixus subtilis Boheman) 杀虫剂室内防治防治效果

Quantum Neural Network for Quantum Neural Computing

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Research 2024年第1期2023卷 71-80页

作者： Min-Gang Zhou zhi-ping Liu Hua-Lei Yin Chen-Long Li Tong-Kai xu Zeng-Bing Chen National Laboratory of Solid State Microstructures School of PhysicsCollaborative Innovation Center of Advanced MicrostructuresNanjing UniversityNanjing 210093China MatricTime Digital Technology Co.Ltd. Nanjing 211899China

Neural networks have achieved impressive breakthroughs in both industry and *** to effectively develop neural networks on quantum computing devices is a challenging open ***,we propose a new quantum neural network model for quantum neural computing using(classically controlled)single-qubit operations and measurements on real-world quantum systems with naturally occurring environment-induced decoherence,which greatly reduces the difficulties of physical *** model circumvents the problem that the state-space size grows exponentially with the number of neurons,thereby greatly reducing memory requirements and allowing for fast optimization with traditional optimization *** benchmark our model for handwritten digit recognition and other nonlinear classification *** results show that our model has an amazing nonlinear classification ability and robustness to ***,our model allows quantum computing to be applied in a wider context and inspires the earlier development of a quantum neural computer than standard quantum computers.

关键词： quantum thereby breakthrough

Research on shell-side heat and mass transfer with multi-component in LNG spiral-wound heat exchanger under sloshing conditions

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Petroleum Science 2024年第2期21卷 1333-1345页

作者： xue-ping Du Guang-Lei Yu Ya-Cheng xu zhi-Jie Chen Nai-Liang Li Huan-Guang Wang School of Low-carbon Energy and Power Engineering China University of Mining and TechnologyXuzhou221116JiangsuChina Key Laboratory of Thermo-Fluid Science and Engineering MOEXi'an Jiaotong UniversityXi'an710049ShaanxiChina Xi'an Aerospace Propulsion Test Technology Institute Xi'an710100ShaanxiChina

The spiral-wound heat exchanger(SWHE) is the primary low-temperature heat exchanger for large-scale LNG plants due to its high-pressure resistance, compact structure, and high heat exchange efficiency. This paper studied the shell-side heat and mass transfer characteristics of vapor-liquid two-phase mixed refrigerants in an SWHE by combining a multi-component model in FLUENT software with a customized multicomponent mass transfer model. Besides, the mathematical model under the sloshing condition was obtained through mathematical derivation, and the corresponding UDF code was loaded into FLUENT as the momentum source term. The results under the sloshing conditions were compared with the relevant parameters under the steady-state condition. The shell-side heat and mass transfer characteristics of the SWHE were investigated by adjusting the component ratio and other working conditions. It was found that the sloshing conditions enhance the heat transfer performance and sometimes have insignificant effects. The sloshing condition is beneficial to reduce the flow resistance. The comprehensive performance of multi-component refrigerants has been improved and the improvement is more significant under sloshing conditions, considering both the heat transfer and pressure *** results will provide theoretical support for the research and design of multi-component heat and mass transfer enhancement of LNG SWHE under ocean sloshing conditions.

关键词： Spiral-wound heat exchanger Sloshing conditions Two-phase flow Multi-component Heat and mass transfer

Manipulating the Phase Transition Behavior of Dual Temperature-Responsive Block Copolymers by Adjusting Composition and Sequence

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Chinese Journal of Polymer Science 2024年第2期42卷 176-187,I0006页

作者： zhi Zou Xiang xu Hai-Tao Zhao Jian-Nan Cheng Wei-Wei He Li-Fen Zhang Zhen-ping Cheng Suzhou key Laboratory of Macromolecular Design and Precision Synthesis Jiangsu Key Laboratory of Advanced Functional Polymer Design and ApplicationState and Local Joint Engineering Laboratory for Novel Functional Polymeric MaterialsCollege of ChemistryChemical Engineering and Materials ScienceSoochow UniversitySuzhou215123China State Key Laboratory of Radiation Medicine and Protection School for Radiological and Interdisciplinary Sciences(RAD-X)and Collaborative Innovation Center of Radiation Medicine of JiangsuSoochow UniversitySuzhou215123China

Temperature-responsive polymers have garnered significant attention due to their ability to respond to external *** this work,dual temperature-responsive block copolymers are synthesized via reversible addition-fragmentation chain transfer polymerization(RAFT)polymerization utilizing zwitterionic monomer methacryloyl ethyl sulfobetaine(SBMA) and N-isopropyl acrylamide(NIPAAm) as *** thermal responsive behaviors can be easily modulated by incorporating additional hydrophobic monomer benzyl acrylate(BN) or hydrophilic monomer acrylic acid(AA),adjusting concentration or pH,or varying the degree of polymerization of the block chain *** cloud points of the copolymers are determined by UV-Vis spectrophotometry,and these copolymers exhibit both controlled upper and lower critical solu bility temperatures(LCST and UCST) in aqueous *** study analyzes and summarizes the influencing factors of dual temperature responsive block copolymers by exploring the effects of various conditions on the phase transition temperature of temperature-sensitive polymers to explore the relationship between their properties and environment and structure to make them more selective in terms of temperature application range and regulation *** is very interesting that the introduction of poly-acrylic acid(PAA) segments in the middle of di-block copolymer PSBMA_(55)-b-PNIPAAm_(80) to form PSBMA_(55)-b-PAA_(x)-b-PNIPAAm_(80) results in a reversal of temperature-responsive behaviors from 'U'(LCST UCST) type,while the copolymer PSBMA_(55)-b-P(NIPAAm_(80)-co-AA_(x)) *** work provides a clue for tuning the phase transition behavior of polymers for manufacture of extreme smart materials.

关键词： Temperature responsive polymers High critical solubility temperature(UCST) Low critical solubility temperature(LCST) Block copolymers

Prediction of contact resistance of electrical contact wear using different machine learning algorithms

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Friction 2024年第6期12卷 1250-1271页

作者： Zhen-bing CAI Chun-lin LI Lei YOU xu-dong CHEN Li-ping HE Zhong-qing CAO zhi-nan ZHANG Tribology Research Institute Southwest Jiaotong UniversityChengdu 610031China State Key Laboratory of Mechanical System and Vibration Shanghai Jiao Tong UniversityShanghai 200240China

H62 brass material is one of the important materials in the process of electrical energy transmission and signal transmission,and has excellent performance in all *** the wear behavior of electrical contact pairs is particularly complex when they are in service,we evaluated the effects of load,sliding velocity,displacement amplitude,current intensity,and surface roughness on the changes in contact *** learning(ML)algorithms were used to predict the electrical contact performance of different factors after wear to determine the correlation between different factors and contact *** forest(RF),support vector regression(SVR)and BP neural network(BPNN)algorithms were used to establish RF,SVR and BPNN models,respectively,and the experimental data were trained and *** was proved that BP neural network model could better predict the stable mean resistance of H62 brass alloy after *** analysis shows that the load and current have great influence on the predicted electrical contact *** wear behavior of electrical contacts is influenced by factors such as load,sliding speed,displacement amplitude,current intensity,and surface roughness during *** learning algorithms can predict the electrical contact performance after wear caused by these *** results indicate that an increase in load,current,and surface roughness leads to a decrease in stable mean resistance,while an increase in displacement amplitude and frequency results in an increase in stable mean resistance,leading to a decline in electrical contact *** reduce testing time and costs and quickly obtain the electrical contact performance of H62 brass alloy after wear caused by different factors,three algorithms(random forest(RF),support vector regression(SVR),and BP neural network(BPNN))were used to train and test experimental results,resulting in a machine learning model suitable for predicting the stable mean

关键词： electrical contact wear contact resistance machine learning(ML) neural network

3D robust anisotropic diffusion filtering algorithm for sparse view neutron computed tomography 3D image reconstruction

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Nuclear Science and Techniques 2024年第3期35卷 13-29页

作者： Yang Liu Teng-Fei Zhu zhi Luo Xiao-ping Ouyang School of Nuclear Science and Engineering North China Electric Power UniversityBeijing 102206China State Key Laboratory of Nuclear Resources and Environment East China University of TechnologyNanchang 330013China State Key Laboratory of Intense Pulsed Radiation Simulation and Effect Xi’an 710024China

The most critical part of a neutron computed tomography(NCT) system is the image processing algorithm,which directly affects the quality and speed of the reconstructed *** types of noise in the system can degrade the quality of the reconstructed ***,to improve the quality of the reconstructed images of NCT systems,efficient image processing algorithms must be *** anisotropic diffusion filtering(ADF) algorithm can not only effectively suppress the noise in the projection data,but also preserve the image edge structure information by reducing the diffusion at the image ***,we propose the application of the ADF algorithm for NCT image *** compare the performance of different algorithms in NCT systems,we reconstructed images using the ordered subset simultaneous algebraic reconstruction technique(OS-SART) algorithm with different regular terms as image processing *** the iterative reconstruction,we selected two image processing algorithms,the Total Variation and split Bregman solved total variation algorithms,for comparison with the performance of the ADF ***,the filtered back-projection algorithm was used for comparison with an iterative *** reconstructing the projection data of the numerical and clock models,we compared and analyzed the effects of each algorithm applied in the NCT *** on the reconstruction results,OS-SART-ADF outperformed the other algorithms in terms of denoising,preserving the edge structure,and suppressing *** example,when the 3D Shepp–Logan was reconstructed at 25 views,the root mean square error of OS-SART-ADF was the smallest among the four iterative algorithms,at only *** universal quality index,mean structural similarity,and correlation coefficient of the reconstructed image were the largest among all algorithms,with values of 0.9877,0.9878,and 0.9887,respectively.

关键词： NCT OS-SART Sparse-view Anisotropic diffusion filtering

Treatment of a dyeing wastewater from a woolen mill using an A/O membrane bio-reactor

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Journal of Environmental Sciences 2000年第3期12卷 344-348页

An anaerobic/oxic membrane bioreactor (A/O MBR) was used for treatment of dyeing wastewater from a woolen mill. COD and color of the wastewater were 54—473 mg/L and 40—400 dilution time (DT) respectively. The ratio of BOD 5/COD was less than 0.13. By the A/O MBR process, the average removal of COD, BOD 5, color and turbidity was 82%, 96%, 71% and 99%, respectively. The average COD, BOD 5, color and turbidity of effluent was 37 mg/L, 0.8 mg/L, 40 DT and 0.44 NUT respectively. The effluent COD met the local standard of reuse water in Beijing, China. The average COD volume load of the anaerobic biological tank was 0.0483 kgCOD/(m 3·d) and that of the aeration tank of the MBR was 0.3589 kgCOD/(m 3·d). The sludge load of the MBR was 0.19 kgCOD/(kg·MLSS·d) on average and the maximum of that was 0.4 kgCOD/(kg·MLSS·d). The flux of the A/O membrane bioreactor could be remained at larger than 50 L/(h·m 2·0.1MPa). The results indicated that A/O membrane bioreactor has technical feasibility for treatment of woolen mill wastewater.

关键词： membrane bioreactor dyeing wastewater biological process membrane technology activated sludge

Optimal proportioning of iron ore in sintering process based on improved multi-objective beluga whale optimisation algorithm

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Journal of Iron and Steel Research International 2024年第7期31卷 1597-1609页

作者： Zong-ping Li xu-dong Li xue-tong Yan Wu Wen Xiao-xin Zeng Rong-jia Zhu Ya-hui Wang Ling-zhi Yi Zhongye Changtian International Engineering Co. Ltd.Changsha 410205HunanChina College of Automation and Electronic Information Xiangtan UniversityXiangtan 411105HunanChina College of Electrical and Information Engineering Hunan UniversityChangsha 410082HunanChina

Proportioning is an important part of sintering,as it affects the cost of sintering and the quality of sintered *** address the problems posed by the complex raw material information and numerous constraints in the sintering process,a multi-objective optimisation model for sintering proportioning was established,which takes the proportioning cost and TFe as the optimisation ***,an improved multi-objective beluga whale optimisation(IMOBWO)algorithm was proposed to solve the nonlinear,multi-constrained multi-objective optimisation *** algorithm uses the con-strained non-dominance criterion to deal with the constraint problem in the ***,the algorithm employs an opposite learning strategy and a population guidance mechanism based on angular competition and two-population competition strategy to enhance convergence and population *** actual proportioning of a steel plant indicates that the IMOBWO algorithm applied to the ore proportioning process has good convergence and obtains the uniformly distributed Pareto ***,compared with the actual proportioning scheme,the proportioning cost is reduced by 4.3361¥/t,and the TFe content in the mixture is increased by 0.0367%in the optimal compromise ***,the proposed method effectively balances the cost and total iron,facilitating the comprehensive utilisation of sintered iron ore resources while ensuring quality assurance.

关键词： Sintering process Proportioning Iron ore Multi-objective beluga whale optimisation algorithm Proportioning cost