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复杂地质条件下地铁深基坑设计与地下水控制方案研究

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中国高新科技 2024年第10期 149-151页

作者：姜忠华上海市隧道工程轨道交通设计研究院上海200000

在城市地铁建设中,深基坑工程因其涉及复杂地质条件及地下水控制问题而成为研究重点。文章通过分析深基坑支护结构的设计挑战提出了地下连续墙、周边环境变形控制及地下水控制的技术方案,并结合案例提出针对复杂地质条件下地铁深基坑设... 详细信息

在城市地铁建设中,深基坑工程因其涉及复杂地质条件及地下水控制问题而成为研究重点。文章通过分析深基坑支护结构的设计挑战提出了地下连续墙、周边环境变形控制及地下水控制的技术方案,并结合案例提出针对复杂地质条件下地铁深基坑设计与地下水控制的有效方法。

关键词：地铁深基坑地下连续墙地下水控制环境保护

Role of Solute Rare Earth in Altering Phase Transformations during Continuous Cooling of a Low Alloy Cr–Mo–V Steel

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金属学报:英文版 2023年第9期36卷 1523-1535页

作者： zhonghua jiang Pei Wang Dianzhong Li Shenyang National Laboratory for Materials Science Institute of Metal ResearchChinese Academy of SciencesShenyang110016China

Effects of solute rare earth(RE)on continuous cooling transformation of a low-alloy Cr–Mo–V bainitic steel are investigated in detail by dilatometry,optical microscopy(OM),scanning electron microscopy(SEM)and transmission electron microscopy(TEM).Microstructures appeared in thermal dilatometric samples of both low-alloy Cr–Mo–V(RE)steels are composed of quasi-polygonal ferrite(QPF),degenerate pearlite(DP),granular bainite(GB),lath bainite(LB),and martensite(M)depending on cooling *** cooling rate is lower than 2°C/s,the addition of RE suppresses QPF transformation,and thereby inducing a broader transformation region of *** cooling rate ranges from 2 to 100°C/s,the addition of RE decreases the start temperature of bainitic transformation distinctly,which results in finer bainitic ferrite grain size and higher dislocation *** addition of RE can enhance the hardness of the low alloy Cr–Mo–V steel by affecting the aforementioned diffusional and/or partly displacive ***,when cooling rate increases up to 150°C/s,two steels have the same hardness value of about 435 HV due to only martensite obtained by displacive transformation.

关键词： Low-alloy Cr-Mo-V steel Rare earth Phase transformation Bainitic microstructures Continuous cooling transformation

Effects of rare earth on microstructure and impact toughness of low alloy Cr-Mo-V steels for hydrogenation reactor vessels

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Journal of Materials Science & Technology 2020年第10期42卷 1-14页

作者： zhonghua jiang Pei Wang Dianzhong Li Yiyi Li Shenyang National Laboratory for Materials Science Institute of Metal ResearchChinese Academy of Sciences72 Wenhua RoadShenyang 110016China School of Materials Science and Engineering University of Science and Technology of China72 Wenhua Road.Shenyang 110016China

The effects of rare earth(RE) on the microstructure and impact toughness of low alloy Cr-Mo-V bainitic steels have been investigated where the steels have RE content of 0 to 0.048 wt.%. The results indicate that the normalized microstructures of the steels are typical granular bainite(GB) composed primarily of bainitic ferrite and martensite and/or austenite(M-A) constituents. The M-A constituents are transformed into ferrite and carbides and/or agglomerated carbides after tempering at 700℃ for 4 h. The addition of RE decreases the onset temperature of bainitic transformation and results in the formation of finer bainitic ferrite, and reduces the amount of carbon-rich M-A constituents. For the normalized and tempered samples, the ductile-to-brittle transition temperature(DBTT) decreases with increasing RE content to a critical value of 0.012 wt.%. Lower DBTT and higher upper shelf energy are attributed to the decreased effective grain size and lower amount of coarse agglomerated carbides from the decomposition of massive M-A constituents. However, the addition of RE in excess of 0.012 wt.% leads to a substantial increase in the volume fraction of large-sized inclusions, which are extremely detrimental to the impact toughness.

关键词： Low alloy Cr-Mo-V steel Rare earth Microstructure Impact toughness Granular bainite Martensite-austenite constituents

Effect of a modified quenching on impact toughness of 52100 bearing steels

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Journal of Materials Science & Technology 2023年第29期160卷 96-108页

作者： Yonghan Li zhonghua jiang Pei Wang Dianzhong Li Yiyi Li Shenyang National Laboratory for Materials Science Institute of Metal ResearchCASShenyang 110016China School of Materials Science and Engineering University of Science and Technology of ChinaHefei 230026China

In order to improve the uniformity of microstructures,and thus enhance the mechanical properties,espe-cially the impact toughness,of 52100 bearing steels,modified quenching heat treatments with different austenitizing processes have been *** results show that 740°C is the optimal holding tem-perature(approaching Ac 1=750°C)to improve the impact toughness of the steel by 37%after quench-ing and low-temperature *** observations reveal that 740°C holding shortens the nucleation incubation period of austenitization phase transformation,and inhibits the overfast growth of austenite in some regions,which leads to simultaneous nucleation and growth of austenite during austen-itizing,and homogeneous dissolution of carbides in different austenite *** changes in microstruc-ture evolution improve the microstructure uniformity(carbide and grain size)after *** distributed carbides and grain size effectively reduce stress concentration and retard crack propagation during impact loading,thus resulting in high impact toughness.

关键词： Austenitizing process Carbides distribution Impact toughness 52100 steels

基于肺腺癌脑转移瘤CT灌注成像参数对肺腺癌EGFR基因突变状态预测的初步研究

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中国中西医结合影像学杂志 2024年第2期22卷 180-183页

作者：姜春成姜中华刘歆曲倩倩王云强山东省烟台市中医医院影像科山东烟台264013 山东省烟台市中医医院肿瘤科山东烟台264013

目的:应用肺腺癌患者脑转移瘤的CT灌注成像参数预测肺腺癌表皮生长因子受体(EGFR)基因的突变状态。方法:回顾性分析接受治疗并完成肺癌病理及EGFR基因检测的45例肺腺癌脑转移患者(EGFR突变型26例,EGFR野生型19例)。所有患者均行颅脑CT... 详细信息

目的:应用肺腺癌患者脑转移瘤的CT灌注成像参数预测肺腺癌表皮生长因子受体(EGFR)基因的突变状态。方法:回顾性分析接受治疗并完成肺癌病理及EGFR基因检测的45例肺腺癌脑转移患者(EGFR突变型26例,EGFR野生型19例)。所有患者均行颅脑CT灌注成像,应用颅脑CT灌注图像分割强化肿瘤和瘤周水肿,提取CT灌注参数。应用具有显著相关性的灌注参数预测EGFR基因的突变状态。采用ROC曲线评估脑转移瘤CT灌注成像参数预测肺腺癌EGFR基因突变状态的效能。结果:灌注参数中,脑血流量(CBF)和平均通过时间(MTT)在肺腺癌2种EGFR基因突变状态中差异均有统计学意义(均P<0.05)。CBF和MTT联合预测肺腺癌EGFR基因突变状态的AUC为0.790。结论:原发性肺腺癌患者脑转移瘤的CT灌注成像参数可用于预测EGFR突变状态。

关键词：体层摄影术,X线计算机灌注成像脑转移瘤表皮生长因子受体基因突变

THERMAL AWARE FLOORPLANNING USING GAUSS-SEIDEL METHOD

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Journal of Electronics(China) 2008年第6期25卷 845-851页

作者： Xu Ning jiang zhonghua School of Computer Sciences and Technology Wuhan University of Technology Wuhan 430070 China

The Gauss-Seidel method is effective to solve the traditional sparse linear system. In the paper, we define a class of sparse linear systems in iterative algorithm. The iterative method for linear system can be extended to the dummy sparse linear system. We apply the Gauss-Seidel method, which is one of the iterative methods for linear system, to the thermal model of floorplan of VLSI physical design. The experimental results of dummy sparse linear system are computed by using Gauss-Seidel method that have shown our theory analysis and extendibility. The iterative time of our incremental thermal model is 5 times faster than that of the inverting matrix method.

关键词： Thermal Floorplanning Gauss-Seidel method

Determination of solubility of uranium in liquid sodium

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Nuclear Science and Techniques 2008年第2期19卷 93-98页

作者： YANG Tongzai XING Pifeng YE Shiyou LONG Kaiming FU zhonghua HE Yuhui jiang Tao Institute of Nuclear Physics and Chemistry China Academy of Engineering Physics Mianyang 621900 China

An experimental technique has been developed which overcomes the two major problems common to liquid metal solubility measurements,namely,maintaining the integrity of the samples during transfer of the liquid sodium from container to whatever device is used for analysis and detecting solute at very low concentration in liquid *** solubility of uranium in liquid sodium has been measured over the temperature range 150～400℃,by equilibration and sampling technique,the solubility of uranium is approximately 0.00001%.

关键词：溶解度铀液态钠核技术

DCCS:A General-Purpose Distributed Cryptographic Computing System

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Wuhan University Journal of Natural Sciences 2007年第1期12卷 46-50页

作者： jiang zhonghua LIN Dongdai XU Lin LIN Lei State Key Laboratory of Information Security Institute ofSoftware Chinese Academy of Sciences Beijing 100080 China Graduate School of the Chinese Academy of Sciences Beijing 100049 China

Distributed cryptographic computing system plays an important role since cryptographic computing is extremely computation sensitive. However, no general cryptographic computing system is available. Grid technology can give an efficient computational support for cryptographic applications. Therefore, a general-purpose grid-based distributed computing system called DCCS is put forward in this paper. The architecture of DCCS is simply described at first. The policy of task division adapted in DCCS is then presented. The method to manage subtask is further discussed in detail. Furthermore, the building and execution process of a computing job is revealed. Finally, the details of DCCS implementation under Globus Toolkit 4 are illustrated.

关键词： cryptography distributed computing execution plan computational grid

Physically modulated phytoplankton production and export at submesoscales in the oligotrophic South China Sea Basin

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Science China Earth Sciences 2024年第8期67卷 2681-2698页

作者： zhonghua ZHAO Mengdi XU Bangqin HUANG Wenfang LU Hongshuai QI Feng CAI Yuwu jiang State Key Laboratory of Marine Environmental Science Xiamen UniversityXiamen 361102China College of Ocean and Earth Sciences Xiamen UniversityXiamen 361102China Fujian Provincial Key Laboratory for Coastal Ecology and Environmental Studies Xiamen UniversityXiamen 361102China National Observation and Research Station for the Taiwan Strait Marine Ecosystem Xiamen UniversityXiamen 361102China School of Marine Sciences Sun Yat-Sen UniversitySouthern Marine Science and Engineering Guangdong Laboratory(Zhuhai)Zhuhai 519000China Laboratory of Ocean and Coast Geology Third Institute of OceanographyMinistry of Natural ResourcesXiamen 361005China

Oceanic submesoscales can significantly influence phytoplankton production and export owing to their similar timescales of *** on two-year Biogeochemical Argo(BGC-Argo) observations,this study investigated the development of submesoscale instabilities,particularly symmetric and mixed-layer baroclinic instabilities,and their impacts on biological production and export in the oligotrophic South China Sea *** the northern basin,near-surface winter blooms consistently cooccurred with seasonally deepened mixed ***,significantly stronger and weaker winter blooms were observed over two consecutive winters within the BGC-Argo observation *** the first winter,symmetric-instability-induced upward nutrient entrainment played a crucial role in initiating the strong winter bloom in early December,when the mixed layer was approximately 20–30 m shallower than the *** bloom occurred approximately 20–30 days earlier than that anticipated owing to the contact between the seasonally deepened mixed layer and mesoscale-cyclone-induced uplifted *** symmetric instability also facilitated the export of fixed phytoplankton carbon from the surface to deeper ***,during the second winter,remarkably intense mixed-layer baroclinic instability associated with an intense mesoscale anticyclone led to more significant shoaling of the mixed layer compared to the nutricline,thus increasing the vertical distance between the two *** this condition,upward nutrient injection,phytoplankton bloom,and carbon export were *** contrast,the BGC-Argo float in the central basin revealed significantly inhibited seasonality of phytoplankton biomass and submesoscale instabilities compared to those in the northern basin,primarily owing to the significantly shallower winter mixed layer.

关键词： Submesoscale instability Phytoplankton Nutrient transport BGC-Argo South China Sea