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化学推进剂与高分子材料 2024年第1期22卷 37-41页

作者：吴冬惠袁巍金梦超郑佳伟李宏国酒泉卫星发射中心甘肃酒泉732750

介绍了偏二甲肼、四氧化二氮、肼、甲基肼、单推–3等常用液体推进剂的理化特性,以及推进剂库管人员的职业暴露类型和主要伤害。通过分析、识别推进剂库管人员作业主要危险源、职业暴露时机和可能伤害,提出针对性职业暴露防护对策,保证... 详细信息

介绍了偏二甲肼、四氧化二氮、肼、甲基肼、单推–3等常用液体推进剂的理化特性,以及推进剂库管人员的职业暴露类型和主要伤害。通过分析、识别推进剂库管人员作业主要危险源、职业暴露时机和可能伤害,提出针对性职业暴露防护对策,保证库管人员职业健康。

关键词：液体推进剂肼四氧化二氮职业暴露防护对策

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特高压平板闸阀设计与密封性能分析

石油矿场机械 2024年第1期53卷 44-49页

作者：樊春明郑家伟杜文波韩传军刘鸣李中华宝鸡石油机械有限责任公司陕西宝鸡721002 国家油气钻井装备工程技术研究中心陕西宝鸡721002 西南石油大学机电工程学院四川成都610065

针对特高压井口平板闸阀设计指导空缺问题,参考API 6A和API 6D标准中的平板闸阀设计参数确定方法,给出175 MPa工作内压下阀体通径为78 mm的平板闸阀设计参数,补充并完善了国内外特高压井口平板闸阀设计方法,对所设计的平板闸阀采用有限... 详细信息

针对特高压井口平板闸阀设计指导空缺问题,参考API 6A和API 6D标准中的平板闸阀设计参数确定方法,给出175 MPa工作内压下阀体通径为78 mm的平板闸阀设计参数,补充并完善了国内外特高压井口平板闸阀设计方法,对所设计的平板闸阀采用有限元法分析其在螺栓预紧工况、额定工作内压工况和1.5倍静水压工况下的密封性能。所设计的平板闸阀可以满足密封准则,且能应对一定量的动载荷,可为特高压井口平板闸阀设计提供参考。

关键词：特高压井口装备平板闸阀密封载荷

Transepithelial transport of nanoparticles in oral drug delivery:From the perspective of surface and holistic property modulation

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Acta Pharmaceutica Sinica B 2024年第9期14卷 3876-3900页

作者： Yaxian zheng Shiqin Luo Min Xu Qin He Jiang Xie jiawei Wu Yuan Huang Department of Pharmacy the Third People’s Hospital of Chengduthe Affiliated Hospital of Southwest Jiaotong UniversityCollege of MedicineSouthwest Jiaotong UniversityChengdu 610031China Department of Pharmacy Personalized Drug Therapy Key Laboratory of Sichuan ProvinceSichuan Academy of Medical Sciences&Sichuan Provincial People’s HospitalSchool of MedicineUniversity of Electronic Science and Technology of ChinaChengdu 610072China Key Laboratory of Drug-Targeting and Drug Delivery System of the Education Ministry and Sichuan Province Sichuan Engineering Laboratory for Plant-Sourced Drug and Sichuan Research Center for Drug Precision Industrial TechnologyWest China School of PharmacySichuan UniversityChengdu 610041China

Despite the promising prospects of nanoparticles in oral drug delivery,the process of oral administration involves a complex transportation pathway that includes cellular uptake,intracellular trafficking,and exocytosis by intestinal epithelial cells,which are necessary steps for nanoparticles to enter the bloodstream and exert therapeutic *** researchers have identified several crucial factors that regulate the interaction between nanoparticles and intestinal epithelial cells,including surface properties such as ligand modification,surface charge,hydrophilicity/hydrophobicity,intestinal protein corona formation,as well as holistic properties like particle size,shape,and *** these properties is essential for enhancing transepithelial transport efficiency and designing effective oral drug delivery ***,this review provides a comprehensive overview of the surface and holistic properties that influence the transepithelial transport of nanoparticles,elucidating the underlying principles governing their impact on transepithelial *** review also outlines the chosen of parameters to be considered for the subsequent design of oral drug delivery systems.

关键词： Oral delivery Nanoparticles Intestinal epithelial cells Surface property Holistic property Transepithelial transport

Intralesional pingyangmycin injection sclerotherapy for oral ranulas

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Open Journal of Stomatology 2013年第7期3卷 359-364页

作者： Zhifang Chen jiawei zheng Shanyong Zhang Department of Oral and Maxillofacial Surgery Hefei Stomatological Hospital Clinical School of Anhui Medical University Hefei China Department of Oral and Maxillofacial Surgery Ninth People’s Hospital College of Stomatology Shanghai Jiao Tong University School of Medicine Shanghai China

Objective: To investigate the efficiency of pingyangmycin (PYM) intralesional injection for the treatment of ranulas in clinical practice. Methods: PYM concentrations were 2.0 mg/ml (8 mg PYM powder + 1 ml normal saline + 2 ml 2% lidocaine + 1 ml dexamethasone). The mixed PYM solution was intralesional injected into ranulas after drawing out isometric cyst fluid in 3 patients. Results: The ranulas of 3 patients showed total disappearance after the sclerotherapy, and no recurrence was found after 6 months to 3 years’ follow-up. Compared to surgical therapy, the PYM sclerotherapy was advocated by clinicians for its advantages of less injury, no scar, less suffering, etc. Conclusions: PYM is an effective sclerosing agent for ranulas. Intracystic injection of PYM may be an optimal method for the treatment of ranulas.

关键词： Ranula Pingyangmycin Sclerotherapy

Nickel-iron in the second coordination shell boost single-atomicsite iridium catalysts for high-performance urea electrooxidation

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Nano Research 2024年第5期17卷 3919-3926页

作者： Xiaoyu Chen jiawei Wan Jing Chai Liang Zhang Fang Zhang Qinghua Zhang Lin Gu Lirong zheng Ranbo Yu Department of Physical Chemistry School of Metallurgical and Ecological EngineeringUniversity of Science and Technology BeijingBeijing 100083China State Key Laboratory of Biochemical Engineering Key Laboratory of Biopharmaceutical Preparation and DeliveryChinese Academy of SciencesInstitute of Process EngineeringChinese Academy of SciencesBeijing 100190China Center for Combustion Energy School of Vehicle and MobilityState Key Laboratory of Intelligent Green Vehicle and MobilityTsinghua UniversityBeijing 100084China Analysis and Testing Center Beijing Institute of TechnologyBeijing 100081China Beijing National Laboratory for Condensed Matter Physics Institute of PhysicsChinese Academy of SciencesBeijing 100190China Beijing National Center for Electron Microscopy and Laboratory of Advanced Materials Department of Materials Science and EngineeringTsinghua UniversityBeijing 100084China Beijing Synchrotron Radiation Facility Institute of High Energy PhysicsChinese Academy of SciencesBeijing 100049China

Single-atom catalysts(SACs)with high catalytic activity as well as great stability are demonstrating great promotion in electrocatalytic energy conversion,which is also a big challenge to ***,we proposed a facile synthetic strategy to construct nickel-iron bimetallic hydroxide nanoribbon stabilized single-atom iridium catalysts(Ir-NiFe-OH),where the nickel-iron hydroxide nanoribbon not only can serve as good electronic conductor,but also can well stabilize and fully expose single-atom *** as catalyst for urea oxidation reaction(UOR),it exhibited excellent UOR performance that it only needed a low operated potential of 1.38 V to achieve the current density of 100 mA·cm^(-2).In-situ Fourier transform infrared spectroscopy,X-ray absorption spectrum,and density functional theory calculations proved that Ir species are active centers and the existence of both Ni and Fe in the local structure of Ir atom can optimize the d-band center of Ir species,promoting the adsorption of intermediates and desorption of products for *** hydrogen evolution reaction(HER)/UOR electrocatalytic cell demanded voltages of 1.46 and 1.50 V to achieve 50 and 100 mA·cm^(-2),respectively,which demonstrated a higher activity and better stability than those of conventional *** work opens a new avenue to develop catalysts for UORs with boosted activity and stability.

关键词： single-atom iridium coordinate structure nanoribbon urea electrooxidation

Lightweight Object Detection Networks for UAV Aerial Images Based on YOLO

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Chinese Journal of Electronics 2024年第4期33卷 997-1009页

作者： Yanshan LI Jiarong WANG Kunhua ZHANG jiawei YI Miaomiao WEI Lirong zheng Weixin XIE ATR National Key Laboratory of Defense Technology Shenzhen University Guangdong Key Laboratory of Intelligent Information Processing Shenzhen University

Existing high-precision object detection algorithms for UAV(unmanned aerial vehicle) aerial images often have a large number of parameters and heavy weight, which makes it difficult to be applied to mobile *** propose three YOLO-based lightweight object detection networks for UAVs, named YOLO-L, YOLO-S, and YOLO-M, respectively. In YOLO-L, we adopt a deconvolution approach to explore suitable upsampling rules during training to improve the detection accuracy. The convolution-batch normalization-Si LU activation function(CBS)structure is replaced with Ghost CBS to reduce the number of parameters and weight, meanwhile Maxpool maximum pooling operation is proposed to replace the CBS structure to avoid generating parameters and weight. YOLO-S greatly reduces the weight of the network by directly introducing CSPGhost Neck residual structures, so that the parameters and weight are respectively decreased by about 15% at the expense of 2.4% mAP. And YOLO-M adopts the CSPGhost Neck residual structure and deconvolution to reduce parameters by 5.6% and weight by 5.7%, while m AP only by 1.8%. The results show that the three lightweight detection networks proposed in this paper have good performance in UAV aerial image object detection task.

关键词： Training YOLO Deconvolution Accuracy Object detection Autonomous aerial vehicles Feature extraction

Chitosan/Sodium Alginate Multilayer pH-Sensitive Films Based on Layer-by-Layer Self-Assembly for Intelligent Packaging

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Journal of Renewable Materials 2024年第2期12卷 215-233页

作者： Mingxuan He Yahui zheng Jiaming Shen jiawei Shi Yongzheng Zhang Yinghong Xiao Jianfei Che Key Laboratory of Soft Chemistry and FunctionalMaterials Nanjing University of Science and TechnologyNanjing210094China Collaborative Innovation Center of Biomedical Functional Materials Nanjing Normal UniversityNanjing210046China

The abuse of plastic food packaging has brought about severe white pollution issues around the *** green and sustainable biomass packaging is an effective way to solve this ***,a chitosan/sodium alginate-based multilayer film is fabricated via a layer-by-layer(LBL)self-assembly *** the help of superior interaction between the layers,the multilayer film possesses excellent mechanical properties(with a tensile strength of 50 MPa).Besides,the film displays outstanding water retention property(blocking moisture of 97.56%)and ultraviolet blocking *** is introduced into the film to detect the food quality since it is one natural plant polyphenol that is sensitive to the pH changes ranging from 1 to 13 in food when spoilage *** is noted that the film is also bacteriostatic which is desired for food *** study describes a simple technique for the development of advanced multifunctional and fully biodegradable food packaging film and it is a sustainable alternative to plastic packaging.

关键词： Chitosan alginate layer-by-layer self-assembly pH-sensitive multilayer films

135/8-10M卡爪式水下液压连接器国产化研制

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中国海洋平台 2024年第4期39卷 93-98页

作者：孙传轩郑家伟樊春明仝刚李中华王耀锋雷振军宝鸡石油机械有限责任公司陕西宝鸡721002 中油国家油气钻井装备工程技术研究中心有限公司陕西宝鸡721002 中海石油(中国)有限公司北京研究中心北京100028

在分析国内外技术现状的基础上,详细说明宝鸡石油机械有限责任公司研制的135/8-10M卡爪式水下液压连接器的总体结构、技术参数和有限元分析结果,介绍样机制造和试验情况,并对卡爪式水下液压连接器的结构特点进行总结。该卡爪式水下液压... 详细信息

在分析国内外技术现状的基础上,详细说明宝鸡石油机械有限责任公司研制的135/8-10M卡爪式水下液压连接器的总体结构、技术参数和有限元分析结果,介绍样机制造和试验情况,并对卡爪式水下液压连接器的结构特点进行总结。该卡爪式水下液压连接器具有液压锁紧和多重解锁、位置指示、型面自锁、垫环固位和更换等功能,产品通过挪威船级社(DNV)和中国船级社(CCS)双认证,并取得API 17D证书,开展与用户设备的现场联调测试,有力推动水下油气装备关键部件的国产化。

关键词：水下连接器液压控制卡爪式国产化

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Effect of electric current on the cast micro-structure of Al-Si alloy

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China Foundry 2005年第3期2卷 171-175页

作者： Guangrning XU jiawei zheng Yong LIU Jianzhong CUI The key Laboratory of Electromagnetic Processing Materials of Ministry of Education Northeastern University Shenyang 110004 Liaoning P. R. China

Effect of electric current on the cast microstructure of Al-Si alloy was investigated. It was found that themicrostructure of Al-Si alloy was refined as the electric current was applied during solidification. When DC (Direct Current)was applied in solidification, the eutectic Si flakes are similar to those solidified without current, but its length was shortenedand its distribution was changed ,with most of the Si flakes arrange in the radial direction, because of the electromagneticforce that resulted from the DC. On the other hand, when AC (Alternating Current) was applied during the solidification ofAl-Si alloy, most of the minute hooks on the silicon flakes that were found under DC or without any applied current werebroken into small silicon particles. Through silicon concentration measurement by electron microprobe, it was found that thesilicon content in the α-AI matrix increased with the current application during solidification, and the effect is more obviouswhen AC was applied.

关键词： electric current solidification Al-Si alloy eutectic silicon

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石油机械制造企业ERP系统编码体系的建立

钻采工艺 2007年第5期30卷 114-118页

作者：郑家伟四川石油管理局成都总机械厂

建立科学合理的编码体系是ERP实施的关键基础工作,直接影响到ERP实施的成功与否。文中在成都总机械厂ERP系统成功实施的基础上,提出了石油机械制造企业编码体系,并给出了主要编码实例。

关键词： ERP实施编码体系实例