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Strain-based design for buried pipelines subjected to landslides

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Petroleum Science 2012年第2期9卷 236-241页

作者： Han Bing wang zhiyin Zhao Honglin Jing Hongyuan WuZhangzhong Beijing Key Laboratory of Urban Oil and Gas Distribution Technology China University of PetroleumBeijing 102249China College of Mechanical and Transportation Engineering China University of PetroleumBeijing 102249China PetroChina Pipeline R&D Center LangfangHebei 065000China

Landslides are one of the key problems for stability analysis of pipelines in the western region of China where the geological conditions are extremely complicated. In order to offer a theoretical basis for the pipe-soil interaction, the general finite element program ABAQUS is used to analyze the distribution of pipe strain caused by landslide through which the pipeline passes. In this paper the Ramberg-Osgood constitutive equation is used to study the strain-based mechanical characteristics of pipelines. Different calculation schemas are designed by considering the change of spatial relationship between pipeline and landslide, and the change of D/t, diameter-thickness ratio of pipeline. The results indicate that the pipeline is primarily subjected to tension stress when the landslide crosses the pipeline perpendicularly, the pipe strain is a maximum along the central axis of the landslide, and reverse bending occurs on pipeline at both edges of the landslide. The pipeline is primarily subjected to friction force caused by the downward movement of the landslide, and the friction force is relatively small when the landslide is parallel to the pipeline. The pipe strain is in proportional to D/t, and this means decreasing D/t can help to improve security of pipelines subjected to the landslide.

关键词： Landslide pipeline strain-based design numerical simulation failure mode

PROCESS AND PROPERTIES OF ELECTROLESS PLATING RE-Ni-B-SiC COMPOSITE COATINGS

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Acta Metallurgica Sinica(English Letters) 1995年第2期8卷 118-122页

作者： GUO Zhongcheng LIU Hongkang wang zhiyin wang Min(Kunming Institute of Technology,Kunming. China ) Kunming Inst of Technology Kunming China

Technology and properties of electroless composite RE-Ni-B-SiC coatings have been *** show that stabilizer plys a decisive role in electroless composite Ni-B-SiC,the addition of appropriate quantity of RE(rare earth) into the Ni-B-SiC bath not only increases SiC content in composite coatings,their hardness and wear resistance but also improves crystalline fineness,Wear resistance increases with the increase of *** and wear resistance of composite coatings reach peak values a fter heat treatment at 4OO and 500℃ for 1h respectively.

关键词： electroless plating Ni-B-SiC-RE composite coating

Radar Signal Intra-Pulse Modulation Recognition Based on Deep Residual Network

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Journal of Beijing Institute of Technology 2024年第2期33卷 155-162页

作者： Fuyuan Xu Guangqing Shao Jiazhan Lu zhiyin wang Zhipeng Wu Shuhang Xia No.8511 Research Institute of China Aerospace Science&Industry Corp(CASIC) Nanjing 210007China

In view of low recognition rate of complex radar intra-pulse modulation signal type by traditional methods under low signal-to-noise ratio(SNR),the paper proposes an automatic recog-nition method of complex radar intra-pulse modulation signal type based on deep residual *** basic principle of the recognition method is to obtain the transformation relationship between the time and frequency of complex radar intra-pulse modulation signal through short-time Fourier transform(STFT),and then design an appropriate deep residual network to extract the features of the time-frequency map and complete a variety of complex intra-pulse modulation signal type *** addition,in order to improve the generalization ability of the proposed method,label smoothing and L2 regularization are *** simulation results show that the proposed method has a recognition accuracy of more than 95%for complex radar intra-pulse modulation sig-nal types under low SNR(2 dB).

关键词： intra-pulse modulation low signal-to-noise deep residual network automatic recognition

PROPERTIES OF ELECTRODEPOSITED AMORPHOUS Ni-W-P-SiC COMPOSITE COATINGS

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Acta Metallurgica Sinica(English Letters) 1996年第1期9卷 44-48页

作者： GUO Zhongcheng LIU Hongkang wang zhiyin wang Min(Department of Metallurgy,Kunming institute of Technology,Kunming 650093,China) Kunming Inst of Technology Kunming China

The Effects of heat treatment temperature on the hardness,wear resistance and structure of the amorphous Ni-W-P-SiC composite coatings have been *** results show that Ni-W-P-SiC composite coatings are amorphous under 300℃, partially crystalline at 300-400℃,and crystalline when heat treatment temperature reaches 400℃,the crystals being fine Ni3P phase *** hardness,wear resistance and the crystallization temperature of the composite coatings increase when an additive is added into the *** hardness and wear resistance of the coatings increase with increasing heat treatment temperature,and they will reach their peak values when the heat treatment temperature reaches 400℃.Corrosion experiment indicates that the corrosion resistance of amorphous Ni-W-P-SiC composite coatings in various kinds of corrosive media except nitric acid is better than that of stainless steel *** electron microscopy observation shows that the additive has no effect on the surface appearance of the coatings,but the current density and the pH value have considerable effects on the surface appearance.

关键词： electrodeposition Ni-W-P-SiC composite coating amorphous

Pravastatin alleviates lipopolysaccharide-induced placental TLR4 over-activation and promotes uterine arteriole remodeling without impairing rat fetal development

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The Journal of Biomedical Research 2018年第4期32卷 288-297页

作者： Muyi Yang Zhenyu Diao zhiyin wang Guijun Yan Guangfeng Zhao Mingming Zheng Anyi Dai Yimin Dai Yali Hu Drum Tower Clinical Medical College Nanjing Medical University Department of Obstetrics and Gynecology Nanjing Drum Tower HospitalNanjing University Medical School

Preeclampsia is associated with over-activation of the innate immune system in the placenta,in which toll-like receptor 4（TLR4） plays an essential *** their potent anti-inflammatory effects,statins have been suggested as potential prevention or treatment of preeclampsia,although evidence remains ***,we investigated whether pravastatin could ameliorate preeclampsia-like phenotypes in a previously established lipopolysaccharide（LPS）-induced rat preeclampsia model,through targeting the TLR4/NF-κB *** results showed that pravastatin reduced the blood pressure [maximum decline on gestational day（GD） 12,（101.33±2.49） mmHg vs.（118.3±1.37） mmHg,P〈0.05] and urine protein level [maximum decline on GD9,（3,726.23± 1,572.86） μg vs.（1,991.03 ±609.37）μg,P〈 0.05],which were elevated following LPS *** also significantly reduced the rate of fetal growth restriction in LPS-treated rats（34.10% vs.8.99%,P〈0.05）.Further pathological analyses suggested a restoration of normal spiral artery remodeling in preeclampsia rats by pravastatin *** effects of pravastatin were associated with decreased TLR4/NF-κB protein levels in the placenta and IL-6/MCP-1 levels in ***,no obvious abnormalities in fetal liver,brain,and kidney were found after administration of *** results provide supportive evidence for use of pravastatin in preventing preeclampsia.

关键词： preeclampsia arteriole remodeling pravastatin toll-like receptor 4 fetal development

Upregulation of CD81 in trophoblasts induces an imbalance of Treg/Th17 cells by promoting IL-6 expression in preeclampsia

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Cellular & Molecular Immunology 2019年第3期16卷 302-312页

作者： Hailin Ding Yimin Dai Yi Lei zhiyin wang Dan Liu Ruotian Li Li Shen Ning Gu Mingming Zheng Xiangyu Zhu Guangfeng Zhao Yali Hu Department of Obstetrics and Gynecology Nanjing Drum Tower HospitalNanjing University Medical School210008 NanjingChina Department of Laboratory Medicine Jiangsu Key Laboratory for Molecular MedicineNanjing University Medical School210008 NanjingChina

The disturbance of maternal immune tolerance to a semiallogeneic fetus is recognized as one of the key pathologies of preeclampsia(PE),in which an imbalance between the inflammation-limiting regulatory T cells(Tregs)and the inflammationmediating Th17 cells plays an essential ***,we reported that the abnormal upregulation of tetraspannin CD81 in trophoblast cells(fetal component)participated in the pathogenesis of ***,as one of the potential immune regulatory molecules,whether CD81 induces PE by interfering with the balance of the maternal immune system has not yet been ***,we investigated the relationship between the upregulation of CD81 in trophoblast cells and the imbalance of Treg and Th17 cells in ***,we demonstrated that upregulation of CD81 in trophoblast cells was accompanied by a decrease in Treg cells and an increase in Th17 cells in both the basal plate(placental maternal side)and peripheral blood of patients with *** vitro culture of naïve T cells with medium from the CD81-overexpressing trophoblast cell line HTR-8 resulted in enhanced differentiation of T cells into Th17 cells and decreased the formation of Tregs,which was dependent on the paracrine signaling of IL-6 in trophocytes,induced by *** a CD81-induced PE rat model,we found a significant shift of T cell differentiation towards Th17 cells,and administration of IL-6 antibody mitigated the PE phenotype and the imbalance of the Treg/Th17 *** results define a vital regulatory cascade involving trophocyte-derived CD81,IL-6,and maternal Treg/Th17 cells in the pathogenesis of PE and suggests new therapeutic approaches based on CD81 and IL-6 downregulation to prevent human PE.

关键词： CD81 preeclampsia Treg Th17 trophoblasts immune tolerance IL-6

Placenta-derived IL-32β activates neutrophils to promote preeclampsia development

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Cellular & Molecular Immunology 2021年第4期18卷 979-991页

作者： Dan Liu Qiang Li Hailin Ding Guangfeng Zhao zhiyin wang Chenrui Cao Yimin Dai Mingming Zheng Xiangyu Zhu Qianwen Wu Ya wang Honglei Duan Huirong Tang Xianyan Lu Yayi Hou Yali Hu Department of Obstetrics and Gynecology The Affiliated Drum Tower Hospital of Nanjing University Medical SchoolNanjingChina Department of Obstetrics and Gynecology Drum Tower Clinic Medical College of Nanjing Medical UniversityNanjingJiangsuChina The State Key Laboratory of Pharmaceutical Biotechnology Division of ImmunologyMedical SchoolNanjing UniversityNanjingChina

Immune activation at the maternal-fetal interface is a main pathogenic factor of preeclampsia(PE).Neutrophils(PMNs)are activated in PE patients,but the mechanism and consequences of PMN activation need to be further ***,we demonstrated that interleukin-32(IL-32)expression was significantly upregulated in syncytiotrophoblasts(STBs)and that IL-32β was the major isoform with increased expression in the placenta of severe PE(sPE)***,the level of IL-32 expression in the placenta was correlated with its level in the serum of sPE patients,indicating that IL-32 in the serum is derived mainly from the ***,in vitro experiments showed that IL-32β could highly activate PMNs and that these IL-32β-activated PMNs were better able to adhere to endothelial cells(HUVECs)and enhance the expression of vascular cell adhesion molecule-1(VCAM-1)and intercellular cell adhesion molecule-1(ICAM-1)in HUVECs,which could be reversed by preincubation with the NADPH oxidase inhibitor VAS *** addition,we showed that IL-32β mainly activated PMNs by binding to proteinase ***,IL-32β administration induced a PE-like phenotype in a pregnant mouse *** study provides evidence of the involvement of IL-32β in the pathogenesis of PE.

关键词： IL-32 Neutrophil Preeclampsia ROS HUVEC

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花岗岩低温强度参数与冰胀力的关系研究

岩石力学与工程学报 2010年第A2期29卷 4113-4118页

作者：李云鹏王芝银中国石油大学机械与储运工程学院北京102249 中国石油大学城市油气输配技术北京市重点实验室北京102249

岩石低温强度参数与冰胀力存在一定的关系,基于冰的热力学特性,建立冰胀力与变低温的数学关系。考虑地下LNG储库近区围岩长期处于0℃～-50℃的环境中,利用干燥低温与饱和冻结花岗岩的三轴压缩试验结果,探讨干燥与饱和花岗岩变低温在不... 详细信息

岩石低温强度参数与冰胀力存在一定的关系,基于冰的热力学特性,建立冰胀力与变低温的数学关系。考虑地下LNG储库近区围岩长期处于0℃～-50℃的环境中,利用干燥低温与饱和冻结花岗岩的三轴压缩试验结果,探讨干燥与饱和花岗岩变低温在不同围压水平下的剪切强度指标变化规律;针对Mohr-Coulomb强度准则和广义Mises屈服条件(包括Drucker-Prager强度条件),建立变低温冻结状态下岩石强度参数与温度和冰胀力的关系。研究表明,岩石孔隙冰胀力与随温度变化的冰的力学参数和体胀系数有关,且随温度降低逐渐减小;低温冻结状态下花岗岩内摩擦角和黏聚力与温度和冰胀力有关,冻结饱和状态下的内摩擦角和黏聚力总是大于干燥低温状态。试验结果及强度条件可用于地下LNG储库围岩的长期稳定性研究与评价。

关键词：岩石力学地下LNG储库强度参数冰胀力低温花岗岩

Theoretical Studies on the single water molecule’s effect on the Main channel of H2S + HO2 reaction

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Theoretical Studies on the single water molecule’s effect o...