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某型柴油机台架试验燃烧室、增压器进水问题分析

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内燃机 2024年第2期40卷 41-47页

作者：王树纲刘凯邓瑞中国船舶集团有限公司第七一一研究所上海200090

某型柴油机在备车过程中,发现燃烧室内存在水分。进一步扩大检查范围,发现增压器底部也有积水现象。该故障导致发动机点火不良,无法正常起动。为了查明原因,对柴油机的内部系统和外部系统进行了故障树分析,最终判断燃烧室及增压器进水... 详细信息

某型柴油机在备车过程中,发现燃烧室内存在水分。进一步扩大检查范围,发现增压器底部也有积水现象。该故障导致发动机点火不良,无法正常起动。为了查明原因,对柴油机的内部系统和外部系统进行了故障树分析,最终判断燃烧室及增压器进水的原因为烟气倒灌所致。随后,对烟气中的水蒸气含量以及背压阀的泄漏量进行了计算与分析,并根据分析结果采取了相应的解决措施,经过试验验证,发现该问题已得到解决。

关键词：柴油机燃烧室及增压器进水烟气倒灌

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船用柴油机连杆断裂失效分析

内燃机与动力装置 2024年第2期41卷 90-96页

作者：刘凯仇立兵朱奎王树纲中国船舶集团有限公司第七一一研究所上海200090

为解决某船用柴油机连杆断裂失效故障,分析连杆断口宏观及微观形貌、金相组织及非金属夹杂物、化学成分及力学性能,确定连杆失效原因,提出改进措施并进行验证。分析结果表明:连杆螺纹孔根部加工粗糙造成应力集中,连杆中非金属夹杂物较多... 详细信息

为解决某船用柴油机连杆断裂失效故障,分析连杆断口宏观及微观形貌、金相组织及非金属夹杂物、化学成分及力学性能,确定连杆失效原因,提出改进措施并进行验证。分析结果表明:连杆螺纹孔根部加工粗糙造成应力集中,连杆中非金属夹杂物较多,且存在与螺纹根部呈一定角度的带状偏析,导致非金属夹杂物在螺纹根部露头,加剧应力集中,在交变力作用下产生裂纹并扩展,使连杆断裂。采取降低连杆非金属夹杂物含量、变更连杆锻造工艺、提高连杆螺栓孔加工质量等改进措施后,进行约4000 h实机运行验证,未再发生连杆断裂故障。

关键词：连杆失效分析非金属夹杂物疲劳断裂

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Rapid decompression and desorption induced energetic failure in coal

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Journal of Rock Mechanics and Geotechnical Engineering 2015年第3期7卷 345-350页

作者： shugang wang Derek Elsworth Jishan Liu Department of Energy and Mineral Engineering EMS Energy Institute and G~3 Center Pennsylvania State University School of Mechanical and Chemical Engineering University of Western Australia

In this study, laboratory experiments are conducted to investigate the rapid decompression and desorption induced energetic failure in coal using a shock tube apparatus. Coal specimens are recovered from Colorado at a depth of 610 m. The coal specimens are saturated with the strong sorbing gas CO2 for a certain period and then the rupture disc is suddenly broken on top of the shock tube to generate a shock wave propagating upwards and a rarefaction wave propagating downwards through the *** rapid decompression and desorption has the potential to cause energetic fragmentation in *** types of behaviors in coal after rapid decompression are found, i.e. degassing without fragmentation, horizontal fragmentation, and vertical fragmentation. We speculate that the characteristics of fracture network（e.g. aperture, spacing, orientation and stiffness） and gas desorption play a role in this dynamic event as coal can be considered as a dual porosity, dual permeability, dual stiffness sorbing medium. This study has important implications in understanding energetic failure process in underground coal mines such as coal gas outbursts.

关键词： Rapid decompression Gas desorption Energetic failure Gas outburst Coal

Loose Sand Cemented by Microbial Cementitious Material:Composition,Microstructure and Mechanical Properties

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Journal of Wuhan University of Technology(Materials Science) 2021年第5期36卷 714-719页

作者： ZHAN Qiwei wang shugang LIU Baoya PAN Zhihong YU Xiaoniu QIAN Chunxiang School of Civil Engineering and Architecture Jiangsu University of Science and TechnologyZhenjiang 212100China Guangdong Provincial Key Laboratory of Building Energy Efficiency and Application Technologies Guangzhou UniversityGuangzhou 510006China Training Base PLA Army Engineering UniversityXuzhou 221004China Department of Civil and Environmental Engineering Nanyang Technological UniversitySingapore City639798Singapore College of Materials Science and Engineering Southeast UniversityNanjing 211189China

Through the influence of the dosage of culture solution and calcium source on hardness and compressive strength of samples,the formulation of microbial cementitious materials was optimized and *** influence of temperature on composition,microstructure and mechanical properties of loose sand cemented by microbial cementitious material was compared and analyzed *** the increase of temperature,the performance of loose sand was improved *** with cementitious properties could be induced at higher temperatures,but not at lower *** the temperature was 30℃,loose sand cemented by microbial cementitious material had more calcite and more dense ***,hardness and compressive strength were also *** wind tunnel test showed that the wind erosion resistance was improved obviously and the mass loss was lower at high *** properties of loose sand cemented by microbial cementitious material was measured *** comparative analysis,engineering properties of loose sand were basically unchanged,and there was no negative effect on the later period use of sand.

关键词： loose sand microbial cementitious material calcite microstructure mechanical properties

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类风湿关节炎的中医药特色治疗经验综述

中国中医药现代远程教育 2024年第12期22卷 161-163页

作者：王树刚陈文信尹国富潍坊市中医院风湿病科山东潍坊261000

近年,类风湿关节炎发病率逐渐升高,其致残率较高,严重危害人类健康,给患者的日常生活带来极大痛苦。目前对于类风湿关节炎的治疗,西医一般采用免疫抑制、抗炎镇痛等方法,暂时缓解患者疼痛,但不良作用较大。近几年研究发现,中医治疗类风... 详细信息

近年,类风湿关节炎发病率逐渐升高,其致残率较高,严重危害人类健康,给患者的日常生活带来极大痛苦。目前对于类风湿关节炎的治疗,西医一般采用免疫抑制、抗炎镇痛等方法,暂时缓解患者疼痛,但不良作用较大。近几年研究发现,中医治疗类风湿关节炎具有独特的优势。中医从整体观念出发,针对不同个体,辨证论治施护,并运用独特的中医适宜技术等,临床效果显著。

关键词：痹证类风湿关节炎中医药疗法综述

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黄淮海玉米种业营销形势分析与市场应对策略

中国种业 2024年第4期 1-5页

作者：邢春景王晓友王丽娟石云翔王树刚北京顺鑫国际种业集团有限公司北京101300 山东省济南市历城区农业农村事业发展中心济南250100 三北种业有限公司河北承德068150

随着基地产值不断提升,玉米种子成本持续走高,面对当前玉米种子供大于求偏重的整体形势,去库存、少剩货、求生存已经成为多数种企的主要目标,各大厂商要认真分析市场表象,认清当前市场形势与供需关系,面对销售季可能随时结束的现状,尤... 详细信息

随着基地产值不断提升,玉米种子成本持续走高,面对当前玉米种子供大于求偏重的整体形势,去库存、少剩货、求生存已经成为多数种企的主要目标,各大厂商要认真分析市场表象,认清当前市场形势与供需关系,面对销售季可能随时结束的现状,尤其要注意订单丢失、大退货、价格战等现象,拿出切实可行的预见性策略。通过对当前种业营销形势进行详细分析和预判,深刻剖析市场表现,挖掘相关问题,提出了一系列应对措施,确保营销目标高效实现。

关键词：种业玉米营销差异化供大于求订单铺货新零售管控

0．9m薄煤层SH型槽波频散特征及波形模式

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地球物理学报 2010年第2期53卷 442-449页

作者：杨真冯涛 wang shugang 中国矿业大学矿业工程学院徐州221116 Pennsylvania State University State College 16802 USA 湖南科技大学煤矿安全开采技术湖南省重点实验室湘潭411201

在0.9 m薄煤层中使用放炮方法做微震震源的条件,通过对所采集到的薄煤层槽波信号进行分析,发现薄煤层槽波在频域中存在高频和低频两个独立并且不连续的波段.其中高频区大约以2000 Hz为中心,低频域的中心频率约为490 Hz,并且高频域和低... 详细信息

在0.9 m薄煤层中使用放炮方法做微震震源的条件,通过对所采集到的薄煤层槽波信号进行分析,发现薄煤层槽波在频域中存在高频和低频两个独立并且不连续的波段.其中高频区大约以2000 Hz为中心,低频域的中心频率约为490 Hz,并且高频域和低频域的能量差异不显著.通过时频分析,可以清晰地看到高、低两个频域几乎在同一时刻触发,并且其小波相关系数在这两个域中的分布规律表现出一定的相似性.通过对0.9 m薄煤层槽波频散曲线的理论分析可知,现场观测到的Airy震相的频率及速度和其理论值较为接近.震源置于煤层中心,且炸药能量对顶底板的扰动,对第二阶对称波形模式下槽波高频部分的形成起着关键作用.在这一对称高阶波形模式下槽波的波速基本上和煤层顶底板中S波的波速一致.由于这两个触发的波形模式在时间域中具有相似的特征,建议在高频域和低频域同时发育较好的薄煤层槽波勘探中,可以采用在同一时间域中高低频相结合的方法提高利用槽波勘探分析的效果.

关键词：薄煤层 SH型槽波能谱频散时频分析波形模式

Air interaction around outdoor air-cooled condensers

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Journal of Southeast University(English Edition) 2010年第2期26卷 222-226页

作者：王树刚张腾飞张剑大连理工大学土木工程学院大连116024

In order to increase cooling or heating efficiency,a porous computational fluid dynamics（CFD）model is employed to predict the thermo-fluid status and optimize the placement of outdoor units.A full scale model is established to validate the accuracy of CFD simulation in terms of velocity and temperature *** comparison between the measurement and the simulation shows a good *** evaluating the condensers＇ sucked air temperature with CFD for three units installed in a row,it is found that the minimum separation distance among neighboring units is 0.2 m;a vertical wall should be apart from the unit line by at least 0.8 m;and large different operating pressures among units do not impact the flow rate and the heat transfer of the other units meaningfully.

关键词： air-cooled condensers flow interaction heat transfer optimization computational fluid dynamics(CFD) measurement

PEG400-mediated nanocarriers improve the delivery and therapeutic efficiency of mRNA tumor vaccines

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Chinese Chemical Letters 2024年第5期35卷 314-319页

作者： Wen Xiao Fazhan wang Yangzhuo Gu Xi He Na Fan Qian Zheng shugang Qin Zhongshan He Yuquan Wei Xiangrong Song Department of Critical Care Medicine Frontiers Science Center for Disease-related Molecular NetworkState Key Laboratory of BiotherapyWest China HospitalSichuan UniversityChengdu 610041China Medical Research Center The First Affiliated Hospital of Zhengzhou UniversityZhengzhou UniversityZhengzhou 450000China

Dendritic cell(DC)-targeted delivery of mRNA is a prominent method to boost the efficacy of mRNA tumor *** targeting ligands are often modified on nanocarriers by polyethylene glycol(PEG)linker in mRNA delivery *** the PEG linker length influences the targeting delivery efficiency of mRNA nanocarrier in vivo remains ***,we designed and constructed DC-targeted mRNA delivery systems modified by mannose via different PEG linker lengths(100/400/1000/2000)(MPn-LPX).The top candidate MP_(400)-LPX(the linker was PEG400)showed the optimal mRNA expression and antigen presentation owing to the highly efficient uptake by ***,MP_(400)-LPX could better inhibited tumor growth and extended survival in the E.G7-OVA lymphoma and TC-1 cervical tumor mouse ***,these results demonstrated that PEG400 was the optimal linker for the PEGylated DC-targeted mRNA *** findings provided a new platform for the rational design of targeted mRNA nanovaccines with shorter-length PEG.

关键词： Cancer immunotherapy mRNA vaccines DC-targeted delivery PEGylated liposomes Cellular uptake