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Preliminary study of the electrospray DPE peculiarities from the liquid surface in the presence of the CSWs

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Plasma Science and Technology 2024年第5期26卷 110-120页

作者：贺伟国霍卫杰韩罗峰朱康武王锋王泽坤 School of Mechatronic Engineering and Automation Shanghai UniversityShanghai 200444People’s Republic of China Shanghai Aerospace Electronic Technology Institute Shanghai 201109People’s Republic of China Shanghai Aerospace Control Technology Institute Shanghai 201109People’s Republic of China

The Ultrasonic Electric Propulsion(UEP)system is a cutting-edge propulsion technology that is mostly used on platforms for small satellites(less than 10 kg).The characteristics of droplet partial emissions(DPEs)in the UEP system are investigated using a high-speed imaging technique(an ultra-high speed camera(NAC HX-6)and a long-distance microscope)in this *** experiments demonstrate that there are a few partial emission modes,including left-side emission,double-side emission,and right-side emission,that are present in the droplet emission process of the UEP *** modes are primarily caused by the partial formation of capillary standing waves(CSWs)on the emission surface of the ultrasonic *** emission rate for single-and double-sided emissions varies at different times,indicating that there are different CSWs engaged in droplet emission due to variations in the liquid film thickness and charge state of the liquid ***,as the droplets emit continuously,a raised area on the emission surface appears,with several droplets emitting there as a result of charge ***,photos of the CSWs with emitting droplets are obtained,which highlights the CSWs'distinctive wave morphology.

关键词： ultrasonic electric propulsion system microsatellite high-speed imaging technique droplet partial emissions electric field

PFNA内固定术治疗老年股骨转子间骨折的临床研究

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临床研究 2024年第5期32卷 97-99页

作者：段洛锋洛宁县人民医院骨科河南洛宁471700

目的对老年股骨转子间骨折患者进行股骨近端防旋髓内钉(PFNA)内固定术治疗,并评估其临床效果。方法以乱数表法将2019年3月至2022年3月洛宁县人民医院收入的86例老年股骨转子间骨折患者分为对照组[动力髋螺钉(DHS),43例]、观察组(PFNA,43... 详细信息

目的对老年股骨转子间骨折患者进行股骨近端防旋髓内钉(PFNA)内固定术治疗,并评估其临床效果。方法以乱数表法将2019年3月至2022年3月洛宁县人民医院收入的86例老年股骨转子间骨折患者分为对照组[动力髋螺钉(DHS),43例]、观察组(PFNA,43例),分析两组治疗效果。结果观察组患者切口长度及引流量均低于对照组,且术中出血量、手术时间卧床时间及骨折愈合时间均短于对照组,差异有统计学意义(P<0.05);术后1个月、术后3个月、术后6个月观察组患者髋关节功能评分均高于对照组,差异有统计学意义(P<0.05);观察组患者并发症发生率(9.30%)低于对照组(25.58%),差异有统计学意义(P<0.05)。结论DHS、PFNA内固定治疗在老年股骨转子间骨折中均具有良好的治疗效果,但PFNA内固定创口小,手术时间短,有助于促进骨折愈合,改善髋关节功能,安全性较高,具有良好的临床应用前景。

关键词：动力髋螺钉老年人群股骨转子间骨折股骨近端防旋髓内钉

氧化石墨烯包埋普鲁士蓝复合物的高效电容去离子和水消毒研究

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Science China Materials 2024年第1期67卷 143-152页

作者：李南任攀宇田苗王科 Atif Saleem 刘念余骆峰李鹏 Frontiers Science Center for Flexible Electronics(FSCFE) Xi’an Institute of Flexible Electronics(IFE)and Xi’an Institute of Biomedical Materials&Engineering(IBME)Northwestern Polytechnical University(NPU)Xi’an 710072China School of Ecology and Environment Northwestern Polytechnical University(NPU)Xi’an 710072China

具有除菌性能的电容去离子材料对于制备高效节能同时具备脱盐和抗微生物污染功能的电极材料至关重要,然而由于双电层电吸附机制的影响,多数碳基材料的吸附容量受到限制.同时,近年来部分研究学者通过对电极材料进行抗菌化合物的修饰并用... 详细信息

具有除菌性能的电容去离子材料对于制备高效节能同时具备脱盐和抗微生物污染功能的电极材料至关重要,然而由于双电层电吸附机制的影响,多数碳基材料的吸附容量受到限制.同时,近年来部分研究学者通过对电极材料进行抗菌化合物的修饰并用于电容法水除菌已得到证明.因此为了实现高效、低成本的同时实现电容脱盐和除菌,本研究提出了一种简便的方法制备氧化石墨烯/聚苯胺/普鲁士蓝纳米复合材料作为类法拉第电极用于电容去离子和水消毒应用.所合成的电极材料具有较高的BET表面积(148.08m^(2)g^(-1))、介孔体积(34.02cm^(3)g^(-1))和孔体积(0.66cm^(3)g^(-1)),在1Ag^(-1)下的脱盐容量为91.6mgg^(-1),脱盐率为3.05mgg^(-1)min^(-1).此外,在未添加额外消毒剂的情况下,该复合材料所制备的电极能有效去除和灭活94.0%±3.1%的大肠杆菌,其杀菌效率是活性炭电极的7倍.本研究对未来将普鲁士蓝基复合材料的法拉第电极用于高效环保海水淡化和消毒材料的应用奠定了研究基础.

关键词：氧化石墨烯电容去离子普鲁士蓝水消毒法拉第碳基材料微生物污染海水淡化

基于改进ConvNeXt网络的矿物图像智能识别

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地质通报 2024年第7期43卷 1266-1275页

作者：李雷卢才武江松景文刚王洛锋西安建筑科技大学资源工程学院陕西西安710055 西安市智慧工业感知、计算与决策重点实验室陕西西安710055 洛阳栾川钼业集团股份有限公司河南洛阳471500

矿物识别是地质研究的重要工作,但是如何准确识别矿物仍然是一项重要的挑战。针对矿物形态特征,提出了一种利用迁移学习策略并引入通道注意力的改进ConvNeXt网络矿物图像智能识别模型。首先,利用ImageNet数据集上已预训练的ConvNeXt网... 详细信息

矿物识别是地质研究的重要工作,但是如何准确识别矿物仍然是一项重要的挑战。针对矿物形态特征,提出了一种利用迁移学习策略并引入通道注意力的改进ConvNeXt网络矿物图像智能识别模型。首先,利用ImageNet数据集上已预训练的ConvNeXt网络模型,运用迁移学习的方式,加载到矿物识别模型中;其次,在ConvNeXt网络的基础上,以ConvNeXt块之后与注意力机制相结合的方式,进一步提升其特征融合能力;最后,以26类矿物的矿石图像为研究对象,总计34576张图像,以6∶2∶2比例划分训练集、验证集与测试集,模型在实验训练过程中与VGG19、GoogLeNet、ResNet50、ResNeXt50和ConvNeXt网络相比,收敛速度明显加快。实验结果表明,矿物智能识别模型在准确率、精确率和召回率上分别达到98.58%、98.62%和98.73%,而消融实验证明本文提出的优化方法有助于提升模型性能,同时,通过对不同模型矿物图像特征图的可视化对比分析,验证了本文提出的矿物识别模型对于矿物特征的准确提取,进一步证明了模型的有效性,提高了矿物识别的准确率。

关键词：矿物图像 ConvNeXt 迁移学习注意力机制矿物识别

Trajectory optimization of aerial slung load release for piloted helicopters

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Chinese Journal of Aeronautics 2021年第2期34卷 229-239页

作者： luofeng WANG Renliang CHEN Xufei YAN National Key Laboratory of Science and Technology on Rotorcraft Aeromechanics Nanjing University of Aeronautics and AstronauticsNanjing 210016China

This study aims to provide the pilot with optimal control time histories for stabilization of a helicopter after releasing the slung load in aerial delivery missions. A model with 21 degrees of freedom(21-DOF) has been developed and validated for a helicopter slung load system. The control history is generated with detailed procedure based on trajectory optimization. Effects of the objective function formulation on the results are discussed and rules are obtained to assist in the objective function determination. We conclude that the pilot should first decrease and then increase the collective control and adjust the longitudinal control to stabilize the helicopter after the in-hover slung load release. The obtained control history is reasonable and helpful for safety and efficiency improvement. Effects of path constraints and the Flight Control System(FCS) are studied. More stringent path constraints will lead to longer time spent and more controls. Stronger stiffness and weaker damping from the FCS will cause milder control histories but sharper on-axis state histories.

关键词： Helicopter slung load systems Nonlinear equations Optimal control Pilot inputs Slung load release Trajectory optimization

老化态度在农村社区老年人社会隔离和自我感知老化的中介效应分析

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包头医学院学报 2024年第6期40卷 74-79页

作者：杨梅吴罗凤刘珊郫都区第二人民医院四川成都611733 成都中医药大学

目的:探讨老化态度在农村社区老年人社会隔离和自我感知老化的中介作用。方法:采用便利抽样法,应用一般资料问卷、老化态度量表(AAQ)、社会网络量表(LSNS-6)、简版自我感知老化量表(B-APQ)于2021年6月至2022年5月对成都市422例农村社区... 详细信息

目的:探讨老化态度在农村社区老年人社会隔离和自我感知老化的中介作用。方法:采用便利抽样法,应用一般资料问卷、老化态度量表(AAQ)、社会网络量表(LSNS-6)、简版自我感知老化量表(B-APQ)于2021年6月至2022年5月对成都市422例农村社区老年人进行问卷调查。结果:农村社区老年人自我感知老化得分为(51.80±5.21)分,社会隔离得分为(16.59±3.05)分,老化态度得分为(78.24±6.03)分;自我感知老化与社会隔离呈正相关(r=0.535,P<0.01),与老化态度呈负相关(r=-0.526,P<0.01);老化态度在农村社区老年人社会隔离和自我感知老化间起部分中介作用,中介效应量为0.39[95%CI(0.245~0.432)],占总效应的52.0%。结论:老化态度在农村社区老年人社会隔离和自我感知老化关系中起部分中介作用,社区应帮助老年人建立积极心理状态,减少社会隔离造成的负面影响,促进其获得更多积极的自我感知老化,进而促进健康老龄化。

关键词：自我感知老化老化态度社会隔离农村老年人中介效应

Comparison between controlled landfill reactor and conditioned landfill bioreactor

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Journal of Environmental Sciences 2004年第5期16卷 874-880页

作者： luofeng CHENWan-zhi SONGFu-zhong LIXiao-peng ZHANGGuo-qing CollegeofResourceandEnvironmentalScience ChongqingUniversityChongqing400044China ChongqingEnvironmentalProtectionBureau Chongqing400010China ChongqingConstructionCommittee Chongqing400010China

Bioreactor landfills allow a more active landfill management that recognizes the biological, chemical and physical processes involved in a landfill environment. The laboratory-scale simulators of landfill reactors treating municipal solid wastes were studied, the effect of solid waste size, leachate recirculation, nutrient balance, pH value, moisture content and temperature on the rate of municipal solid waste(MSW) biodegradation were determined, and it indicated the optimum pH value, moisture content and temperature decomposing MSW. The results of waste biodegradation were compared with that of the leachate-recirculated landfill simulator and conservative sanitary landfill simulator. In the control experiment the antitheses of a decreasing trend of the organic load, measured as biological oxygen demand and chemical oxygen demand, was shown. An obvious enhancement of effective disposal from conservative sanitary landfill(CSL) simulator, to the leachate-recirculated landfill(LRL) simulator and to the conditioned bioreactor landfill(CBL) simulator would be noted, through displaying the compared results of solid waste settlement, heavy metal concentration in leachate, methane production rate, biogas composition, BOD and COD as well as their ratio.

关键词： landfill bioreactor methanogenesis methane production municipal solid waste leachate recirculation biodegradation of solid waste specific methanogenic activity(SMA)

基于卷积神经网络和模态转换的磁瓦内部缺陷检测方法

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中国测试 2024年第2期50卷 22-27页

作者：卢后洪谢罗峰朱杨洋殷鸣杜波殷国富四川大学机械工程学院四川成都610065 四川省特种设备检验研究院四川成都610000

针对人工检测磁瓦内部缺陷过程中需要成熟的经验知识,检测过程不稳定且效率较低等问题,设计一套智能化检测系统。受人工检测的启发,提出一种基于卷积神经网络和模态转换的磁瓦内部缺陷检测方法。将时域信号转换为时-频域语谱图,利用卷... 详细信息

针对人工检测磁瓦内部缺陷过程中需要成熟的经验知识,检测过程不稳定且效率较低等问题,设计一套智能化检测系统。受人工检测的启发,提出一种基于卷积神经网络和模态转换的磁瓦内部缺陷检测方法。将时域信号转换为时-频域语谱图,利用卷积神经对语谱图提取特征并分类。为更精准地强调重要信息而抑制无关信息,将坐标注意力机制引入到卷积神经网络中。提出的基于卷积神经网络和模态转换的预测模型的准确率达到98.4%,证明提出的检测方法对于磁瓦内部缺陷检方法是有效的。实验结果表明,模态转换和坐标注意力机制能提升模型的性能。

关键词：磁瓦卷积神经网络(CNN) 内部缺陷模态转换注意力机制

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Rapid inactivation of multidrug-resistant bacteria and enhancement of osteoinduction via titania nanotubes grafted with polyguanidines

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Journal of Materials Science & Technology 2021年第10期69卷 188-199页

作者： Wei Feng Nian Liu Lingling Gao Qian Zhou luofeng Yu Xiaoting Ye Jingjing Huo Xiao Huang Peng Li Wei Huang Key Laboratory of Flexible Electronics(KLOFE)and Institute of Advanced Materials(IAM) Jiangsu National Synergetic Innovation Center for Advanced Materials(S1CAM)Nanjing Tech UniversityNanjing 211816China Frontiers Science Center for Flexible Electronics(FSCFE) Xi'an Institute of Flexible Electronics(IFE)Xi'an Institute of Biomedical Materials and Engineering(IBME)Northwestern Polytechnical University(NPU)Xi'an 710072China The State Key Laboratory of Molecular Engineering of Polymers Department of Macromolecular ScienceFudan UniversityShanghai 200438China

The rapid in situ inhibition of bacterial contamination and subsequent infection without inducing drug resistance is highly vital for the successful implantation and long-term service of titanium(Ti)-based orthopedic ***,the instability and potential cytotoxicity of current coatings have deterred their clinical *** this study,anodic oxidized titania nanotubes(TNT)were modified with antibacterial polyhexamethylene guanidine(PG)with the assistance of 3,4-dihydroxyphenylacetic ***,the prepared TNT-PG coating exhibited superior in vitro antibacterial activity than flat Ti-PG coating and effectively killed typical pathogens such as Escherichia coli and superbug methicillinresistant Staphylococcus aureus with above 4-log reduction(>99.99%killed)in only 5 ***-PG coating also exerted excellent hemocompatibility with red blood cells and nontoxicity toward mouse pre-osteoblasts(MC3 T3-E1)in 1 week of *** addition,the efficient in vivo anti-infective property of this coating was observed in a rat subcutaneous infection *** importantly,TNT-PG coating improved the expression of alkaline phosphatase and enhanced the extracellular matrix mineralization of pre-osteoblasts,denoting its osteoinductive *** versatile TNT-PG coating with excellent antibacterial activity and biocompatibility could be a promising candidate for advanced orthopedic implant applications.

关键词： Biomaterial-associated infection Fast sterilization Titania nanotubes Cationic antimicrobial polymer Bioactive coating