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基于改进灰靶的山区隧道施工场地布置方案优选

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科学技术与工程 2024年第12期24卷 5185-5193页

作者：王景春王屹李永昊刘凯林石家庄铁道大学安全工程与应急管理学院石家庄050043 石家庄铁道大学土木工程学院石家庄050043

为提高山区隧道施工场地布置方案决策的准确性,以牛栾村隧道六种施工场地布置方案为例,提出了基于改进灰靶的方案优选模型。首先,通过分析场地布置方案影响因素,构建了以方案可行性、方案经济性、环境影响和社会效益影响为核心的评价指... 详细信息

为提高山区隧道施工场地布置方案决策的准确性,以牛栾村隧道六种施工场地布置方案为例,提出了基于改进灰靶的方案优选模型。首先,通过分析场地布置方案影响因素,构建了以方案可行性、方案经济性、环境影响和社会效益影响为核心的评价指标体系;其次,采用云模型将定性指标定量描述,并运用CRITIC(criteria importance though intercriteria correlation)确定指标权重;最后以灰色关联差异信息值为基础,结合欧几里得理论计算修正的加权靶心距,通过对比靶心距实现方案优选,并采用单因素轮换法(one-at-a-time,OAT)进行了指标敏感性分析。结果表明:最优方案的加权靶心距为0.610,评选出的方案与实际一致,并分析出“地形地貌改变”为对方案评选影响最大的指标。可见,该方法呈现了各方案的优劣,使山区隧道施工场地布置方案评选更科学、合理。

关键词：山区隧道场地布置方案评选改进灰靶决策指标敏感性分析

Differential Gene and Protein Expression in Soybean at Early Stages of Incompatible Interaction with Phytophthora sojae

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Agricultural Sciences in China 2011年第6期10卷 902-910页

作者： li yong-gang YANG Ming-xiu li Yan liU Wen-wen WEN Jing-zhi li yong-hao Department of Plant Protection Northeast Agricultural University Harbin 150030 P.R.China Department of Plant Pathology and Ecology Connecticut Agricultural Experiment Station 123 Huntington St New Haven CT 06511 USA

Soybean root and stem rot caused by Phytophthora sojae is a destructive disease worldwide. Using genetic resistance is an important and major component in the integrated pest management of this disease. To understand molecular mechanisms of root and stem rot resistance in soybeans, the gene and protein expression in hypocotyls and stems of variety Suinong 10 carrying resistance genes Rps1a and Rps2 was investigated by using mRNA differential display reverse transcription PCR and two-dimensional electrophoresis at 0, 0.5, 1, 2, and 4 h after inoculation with P. sojae race 1. The results of the comparison of gene and protein expression showed that at least eight differential fragments at the transcriptional level were related to metabolic pathway, phytoalexin, and signal transduction in defense responses. Sequence analyses indicated that these fragments represented cinnamic acid 4-hydroxylase gene, ATP b gene coding ATP synthase b subunit and ubiquitin-conjugating enzyme gene which upregulated at 0.5 h post inoculation, blue copper protein gene and UDP-N-acetyl-a-D-galactosamine gene which upregulated at 2 h post inoculation, TGA-type basic leucine zipper protein TGA1.1 gene, cyclophilin gene, and 14-3-3 protein gene which upregulated at 4 h post inoculation. Three resistance-related proteins, a-subunit and b-subunit of ATP synthase, and cytochrome P450-like protein, were upregulated at 2 h post inoculation. The results suggested that resistance-related multiple proteins and genes were expressed in the recognition between soybean and P. sojae during zoospore germination, penetration and mycelium growth of P. sojae in soybean.

关键词： Phytophthora sojae resistance mechanism incompatible interaction mRNA differential display reverse transcription PCR two-dimensional electrophoresis

A fusion protein containing murine vascular endothelial growth factor and tissue factor induces thrombogenesis and suppression of tumor growth in a colon carcinoma model

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Journal of Zhejiang University-Science B(Biomedicine & Biotechnology) 2008年第8期9卷 602-609页

作者： Feng-ying HUANG Yue-nan li Hua WANG yong-hao HUANG Ying-ying liN Guang-hong TAN Hainan Provincial Key Laboratory of Tropical Medicine Hainan Medical College Haikou 571101 China

Induction of tumor vasculature occlusion by targeting a thrombogen to newly formed blood vessels in tumor tissues represents an intriguing approach to the eradication of primary solid tumors. In the current study, we construct and express a fusion protein containing vascular endothelial growth factor (VEGF) and tissue factor (TF) to explore whether this fusion protein has the capability of inhibiting tumor growth in a colon carcinoma model. The murine cDNA of VEGF A and TF were amplified by reverse transcriptase polymerase chain reaction (RT-PCR), and then cloned into prokaryotic expression plasmid pQE30 with a linker. The expression product recombinant VEGF-TF (rVEGF-TF) was purified and proved to have comparable enzyme activity to a commercial TF and the capability of specific binding to tumor vessels. Significant decrease of tumor growth was found in the mice administered with rVEGF-TF on Day 6 after initiated rVEGF-TF treatment (Plid thrombogenesis and tumor necrosis were observed in the tumor tissues injected with rVEGF-TF. Our results demonstrate that occlusion of tumor vasculature with rVEGF-TF is potentially an effective approach for cancer therapy.

关键词： Thrombogenesis Vascular endothelial growth factor (VEGF) Tissue factor (TF) Recombinant fusion protein

Electrochemical intercalation reaction of lithium into sulfides of nonlayer structure ——Ⅰ.lithium intercalation in lead sulfide

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Acta Chimica Sinica(English Edition) 1987年第4期5卷 287-293页

作者： li yong-Fang WU hao-Qing Department of Chemistry,Fudan University,Shanghai Department of Chemistry Fudan University Shanghai

The reaction mechanism of cell li/PbS has been studied with coulombic titration,cyclicvoltammetry and X-ray diffraction *** was found that in the first stage of discharge（0lithium into lead sulfide took *** X-ray diffraction patterns showedthat the main crystalline structure of PbS remained unchanged after lithiation,and the lithium inter-calated probably locates in the center of the cubic-interspace of the *** intercalation freeenergy of li into PbS forming liPbS was found to be-300.48 ***-1（at 25℃）.The chemicaldiffusion coefficient of lithium in liyPbS（0

关键词： Electrochemical intercalation reaction of lithium into sulfides of nonlayer structure

Numerical modeling of fracture propagation of supercritical CO_(2)compound fracturing

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Journal of Rock Mechanics and Geotechnical Engineering 2024年第7期16卷 2607-2628页

作者： hao Chen yong Kang Wanchun Jin Changhai li Can Cai School of Mechanical Engineering Southwest Petroleum UniversityChengdu610500China Laboratory of High-pressure Jet Theory and Application Technology Southwest Petroleum UniversityChengdu610500China Hubei Key Laboratory of Waterjet Theory and New Technology Wuhan UniversityWuhan430072China Sinopec International Petroleum Exploration and Production Corporation Beijing 100029China

The exploitation of shale gas is promising due to depletion of the conventional energy and intensification of the greenhouse *** this paper,we proposed a heat-fluid-solid coupling damage model of supercritical CO_(2)(SC-CO_(2))compound fracturing which is expected to be an efficient and environmentally friendly way to develop shale *** coupling model is solved by the finite element method,and the results are in good agreement with the analytical solutions and fracturing *** on this model,the fracture propagation characteristics at the two stages of compound fracturing are studied and the influence of pressurization rate,in situ stress,bedding angle,and other factors are *** results show that at the SC-CO_(2)fracturing stage,a lower pressurization rate is conducive to formation of the branches around main fractures,while a higher pressurization rate inhibits formation of the branches around main fractures and promotes formation of the main *** bedding and in situ stress play a dominant role in the fracture *** the in situ stress ratio(δ_(x)/δ_(y))is 1,the presence of bedding can reduce the initiation pressure and failure ***,it will cause the fracture to propagate along the bedding direction,reducing the fracture *** rocks without bedding,hydraulic fracturing has the lengthening and widening effects for SC-CO_(2)induced *** shale,fractures induced at the hydraulic fracturing stage are more likely to be dominated by in situ stresses and have a shorter reorientation ***,fracture branches propagating along the maximum principal stress direction may be generated around the main fractures induced by SC-CO_(2)at the hydraulic fracturing *** the branches converge with the main fractures,fracture zones are easily formed,and thus the fracture complexity and damage area can be significantly *** results are instructive for the design and application of SC

关键词： Compound fracturing Fracture propagation Finite element method Damage evolution

Large-disturbance Stability Analysis of Power Systems with Synchronous Generator and Converter-interfaced Generation

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Journal of Modern Power Systems and Clean Energy 2024年第3期12卷 997-1002页

作者： Lei Chen yong Min liangshuai hao Guangzheng Xing Yalou li Shiyun Xu Department of Electrical Engineering Tsinghua UniversityBeijing 100084China China Electric Power Research Institute Beijing 100192China

This letter studies large-disturbance stability of the power system with a synchronous generator(SG)and a converter-interfaced generation(CIG)connected to infinite *** power system is multi-timescale and first *** is shown that the boundary of region of attraction(ROA)of the simplified model is composed of stable manifolds of unstable equilibrium point(UEP)or semi-singular point(SSP),named anchor points,and singular surface *** type of anchor point determines the dominant instability pattern of the power *** the anchor point is UEP or SSP,the dominant instability pattern is the instability of rotor angle of SG or the instability of phase-locked loop and outer control loop(OCL)of CIG,*** of dominant instability pattern can be analyzed with the relative position relationship between UEP and *** effect of OCL is *** the OCL is activated,the ROA becomes smaller and the system is more prone to instability of *** is necessary to consider the OCL when studying the large-disturbance stability of the power system.

关键词： Converter-interfaced generation large-disturbance stability outer control loop phase-locked loop synchronous generator voltage source converter

Temperature prediction model in multiphase flow considering phase transition in the drilling operations

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Petroleum Science 2024年第3期21卷 1969-1979页

作者： Yang Zhang yong-An li Xiang-Wei Kong hao liu Teng-Fei Sun College of Mechanical and Electrical Engineering Beijing University of Chemical TechnologyBeijing 100027China School of Petroleum Engineering Yangtze UniversityWuhan430000HubeiChina

The study considers gas compression properties,gas slippage,back pressure(BP),phase transition(PT),well depth,and differences in gas-liquid physical properties.A new temperature model for multiphase flow is proposed by considering phase transition in the drilling *** mathematical model of multiphase flow is solved using the finite difference method with annulus mesh division for grid nodes,and a module for multiphase flow calculation and analysis is *** results indicate that the temperature varies along the annulus with the variation of gas influx at the bottom of the *** the process of controlled pressure drilling,as gas slips along the annulus to the wellhead,its volume continuously expands,leading to an increase in the gas content within the annulus,and consequently,an increase in the pressure drop caused by gas *** temperature increases with the increase in BP and decreases in gas influx rate and wellbore *** gas influx,the thermal conductivity coefficient for the gas-drilling mud two phases is significantly weakened,resulting in a considerable change in temperature along the *** the context of MPD,the method of slightly changing the temperature along the annulus by controlling the back pressure is feasible.

关键词： Managed pressure drilling Phase transition Temperature Gas-drilling mud two phase

无机水系液流电池中纳米粒子改性石墨毡电极研究

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现代化工 2024年第3期44卷 69-73页

作者：聂昌通韩红静李永浩安梦乾徐俊辉陈留平青海大学机械工程学院青海西宁810016 青海大学新能源光伏产业研究中心青海西宁810016 中盐金坛盐化有限责任公司江苏省井矿盐综合利用工程技术研究中心江苏常州213200

简单介绍了典型液流电池的工作原理及石墨毡本身的结构特征与物化性质,重点阐述了近年来纳米粒子修饰改性电极在液流电池中的应用,对比分析了不同修饰改性工艺及不同类型纳米粒子对电极材料性能的优化效果,并进一步总结了纳米粒子提高... 详细信息

简单介绍了典型液流电池的工作原理及石墨毡本身的结构特征与物化性质,重点阐述了近年来纳米粒子修饰改性电极在液流电池中的应用,对比分析了不同修饰改性工艺及不同类型纳米粒子对电极材料性能的优化效果,并进一步总结了纳米粒子提高电极材料电化学活性机制机理。最后针对电极性能优化研究提出了未来有助于提高电池效率、降低电池成本的发展方向。

关键词：液流电池纳米粒子石墨毡电极改性

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基于PLC的二辊冷轧机自动控制系统设计

机械工程与自动化 2024年第4期 162-165页

作者：周帝宏欧阳泽李永豪王爽王祺重庆科技大学重庆401331

为满足目前对二辊冷轧机轧制过程中精度和效率的需求,在某高校轧制炼钢实验室传统生产工艺不变的基础上,针对轧制过程信息化集成度低等问题,设计了一套控制系统。该系统基于西门子SIMATIC S7-200 SMART PLC进行逻辑处理,采用Modbus协议... 详细信息

为满足目前对二辊冷轧机轧制过程中精度和效率的需求,在某高校轧制炼钢实验室传统生产工艺不变的基础上,针对轧制过程信息化集成度低等问题,设计了一套控制系统。该系统基于西门子SIMATIC S7-200 SMART PLC进行逻辑处理,采用Modbus协议与变频器进行通讯,同时依托于压力传感器和位移传感器的实时反馈,实现了轧制厚度和轧制线速度的精准控制以及轧制过程的自动调节,并通过组态王软件实现了实时生产过程数据可视化。系统的使用结果表明:利用该控制系统提高了轧制过程中的效率和精度,提升了生产过程的信息化集成水平。

关键词：二辊冷轧机 SIMATIC S7-200 SMART PLC 组态王数据可视化