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A semi-analytical multi-harmonic balance method on full-3D contact model for dynamic analysis of dry friction systems

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Chinese Journal of Aeronautics 2024年第2期37卷 309-329页

作者： He sun Dayi ZHANG Yaguang WU Qingyang SHEN Dianyin hu Research Institute of Aero-Engine Beihang UniversityBeijing 100191China School of Energy and Power Engineering Beihang UniversityBeijing 100191China Beijing Key Laboratory of Aero-Engine Structure and Strength Beijing 100191China Sino-French Engineering School Beihang UniversityBeijing 100191China AECC Sichuan Gas Turbine Research Establishment Chengdu 610500China

Dry friction damping structures are widely-used in aero-engines to mitigate *** nonlinear nature of friction and the two-dimensional in-plane motion on the contact interface bring challenges to accurately and efficiently predict the forced response of frictionally damped *** state-of-the-art Multi-Harmonic Balance Method(MHBM)on quasi-3D contact model in engineering cannot precisely capture the kinematics on the friction interface although the efficiency is *** full-3D contact model can describe the constitutive relationship of the interface in a more accurate manner;however,the efficiency and convergence are not guaranteed for large-scale *** this paper,a semi-analytical MHBM on full-3D contact model is *** original Trajectory Tracking Method(TTM)for evaluating the contact force is reformulated to make the calculation more concise and the derivation of the Analytical Jacobian Matrix(AJM)*** on the chain rule of derivation,the AJM which is the core to upgrade the performance is *** a shrouded blade finite element model,the accuracy and efficiency of the proposed method are compared with both the MHBM on full-3D contact model with numerical Jacobian matrix and the MHBM on quasi-3D contact model with *** results show that the AJM improves significantly the efficiency of the MHBM on full-3D contact *** time cost of the proposed method is in the same order of magnitude as that of the MHBM on quasi-3D contact *** also confirm that the full-3D contact model is necessary for the dynamic analyses of shrouded *** one uses the quasi-3D model,the estimation relative error of damping can even reach 31.8%in some *** addition,the AJM also brings benefits for stability *** is highly recommended that engineers use the MHBM on full-3D contact model for the dynamic analysis and design of shrouded blades.

关键词： Dry friction damping Multi-harmonic balance method Trajectory tracking method Jacobian matrix Shrouded blade

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Design of a Bio-inspired,Two-winged,Flapping-wing Micro Air Vehicle with High-lift Performance

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Journal of Bionic Engineering 2024年第3期21卷 1191-1207页

作者： Kai hu huichao Deng Shengjie Xiao Gongyu Yang Yuhong sun Space Robot Laboratory The School of Mechanical EngineeringBeihang UniversityBeijing100191China

In this paper,we present the development of our latest flapping-wing micro air vehicle(FW-MAV),named Explobird,which features two wings with a wingspan of 195 mm and weighs a mere 25.2 g,enabling it to accomplish vertical take-off and hover *** devised a novel gear-based mechanism for the flapping system to achieve high lift capability and reliability and conducted extensive testing and analysis on the wings to optimise power matching and lift *** Explobird can deliver a peak lift-to-weight ratio of 1.472 and an endurance time of 259 s during hover flight powered by a single-cell LiPo *** the inherent instability of the prototype,we discuss the derivatives of its longitudinal system,underscoring the importance of feedback control,position of the centre of gravity,and increased *** demonstrate the effect of damping enhancement on stability,we also designed a passive stable ***,the vehicle is actively stabilised in roll by adjusting the wing root bars and in pitch through high-authority tail control,whereas yaw is passively *** a series of flight tests,we successfully demonstrate that our prototype can perform vertical take-off and hover flight under wireless *** promising results position the Explobird as a robust vehicle with high lift capability,paving the way towards the use of FW-MAVs for carrying load equipment in multiple tasks.

关键词： Flapping wing Biologically inspired robots Mechanical design Flight dynamics Damping enhancement

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赤泥中稀土提取与分离技术研究进展

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化工矿物与加工 2024年第8期53卷 51-61页

作者：杨佩东韩桂洪黄艳芳刘兵兵孙虎郑州大学化工学院郑州大学关键金属河南实验室

稀土元素被誉为“工业维生素”,具有优异的磁、光、电性能。随着新能源汽车等新兴行业对稀土需求量的不断增加，稀土资源日益紧缺，从二次资源中回收稀土已成大势所趋。作为一种重要的二次资源，赤泥的产量高、堆存量大、稀土含量较高... 详细信息

稀土元素被誉为“工业维生素”,具有优异的磁、光、电性能。随着新能源汽车等新兴行业对稀土需求量的不断增加，稀土资源日益紧缺，从二次资源中回收稀土已成大势所趋。作为一种重要的二次资源，赤泥的产量高、堆存量大、稀土含量较高。本文介绍了赤泥中稀土元素的赋存状态，概述了从赤泥中提取分离稀土元素的湿法浸出工艺和火法-湿法联合工艺；介绍了溶剂萃取法和离子交换法两种分离工艺的研究现状，对比分析了不同处理工艺的优缺点，并通过比较不同工艺的优劣，指出降低回收成本、提高环境效益是未来赤泥资源化利用研究的重要方向。

关键词：赤泥稀土提取湿法浸出工艺火法-湿法联合工艺溶剂萃取法离子交换法二次资源

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基于多准则决策的不同剂量瑞马唑仑联合阿芬太尼应用于无痛人工流产术的风险-效益评价

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发育医学电子杂志 2024年第5期12卷 328-336页

作者：林卫欣孙虎吕淞陈乔芳徐志新 (海南医学院第二附属医院麻醉科海南海口570100

目的基于多准则决策模型来评价不同剂量瑞马唑仑联合阿芬太尼应用于无痛人工流产术的风险-效益。方法前瞻性选取2020年6月至2022年2月在海南医学院第二附属医院进行人工流产术的136例孕妇作为研究对象,根据随机数字表法将孕妇分为A组、... 详细信息

目的基于多准则决策模型来评价不同剂量瑞马唑仑联合阿芬太尼应用于无痛人工流产术的风险-效益。方法前瞻性选取2020年6月至2022年2月在海南医学院第二附属医院进行人工流产术的136例孕妇作为研究对象,根据随机数字表法将孕妇分为A组、B组、C组和D组,每组各34例。A组孕妇采用丙泊酚联合阿芬太尼麻醉,B组、C组和D组孕妇分别采用不同剂量(0.1 mg/kg、0.15 mg/kg、0.2 mg/kg)瑞马唑仑联合阿芬太尼麻醉。建立无痛人工流产麻醉效果的多准则决策模型。统计学方法采用独立样本t检验、方差分析、χ^(2)检验。结果D组孕妇的麻醉起效时间短于A组和B组[(1.6±0.4)min与(2.3±0.6)min、(2.0±0.4)min,t值分别为2.634、2.548,P值均<0.05)]。D组孕妇术后疼痛视觉模拟评分(visual analogue scale,VAS)低于A组、B组和C组[(3.8±0.3)分与(4.5±0.8)分、(4.7±0.8)分、(4.5±0.5)分,t值分别为4.085、3.293、3.169,P值均<0.05)]。A组和D组孕妇的Ramsay评分分别为(5.4±0.5)分和(5.4±0.5)分,均高于B组[(4.6±0.4)分]和C组[(4.8±0.4)分](A组和B组、C组间的t值分别为3.516、3.748,D组和B组、C组间的t值分别为3.976、4.526,P值均<0.05)。麻醉后(T1),A组孕妇的平均动脉压(meanarterialpressure,MAP)为(59.4±4.4)mmHg(1mmHg=0.133kPa)、心率(heartrate,HR)为(73.3±6.3)次/min、血氧饱和度(oxygensaturation,SpO2)为(87.2±4.4)%、呼吸频率(respiratory rate,RR)为(11.4±2.3)次/min、脑电双频指数(bispectral index,BIS)为56.3±5.8,波动幅度较其他3组显著(A组和B组间的t值分别为8.237、2.835、2.823、2.857、3.257,A组和C组间的t值分别为8.574、2.674、2.457、2.632、3.485,A组和D组间的t值分别为8.634、2.823、2.162、2.934、5.238,P值均<0.05)。应用Meta分析方法分别合并4组的结果发现,与A组、B组、C组相比,D组孕妇的麻醉起效时间、Ramsay评分、术后VAS评分、MAP、HR、SpO2、RR以及BIS均显著改善,总有效率显著升高,不良反应发生率显著降低,表明D组麻醉效果较好。通过计算4组的效益值、风险值以及风险-效益总值,结果显示,D组的效益高、风险低。当效益与风险都很重要时,D组麻醉方法的风险-效益总值最高,无论风险-效益的相对权重如何改变,模型评价结果均保持不变,说明该模型稳定性良好。结论在无痛人工流产术中,0.2 mg/kg瑞马唑仑联合阿芬太尼的麻醉效果较好,可有效维持生命体征平稳,并降低不良反应发生率。

关键词：多准则决策无痛人工流产瑞马唑仑阿芬太尼效益风险

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Simulation Study on the Heat Transfer Characteristics of a Spray-Cooled Single-Pipe Cooling Tower

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Fluid Dynamics & Materials Processing 2024年第9期20卷 2109-2126页

作者： Kaiyong hu Zhaoyi Chen Yunqing hu huan sun Zhili sun Tonghua Zou Jinghong Ning Tianjin Key Lab of Refrigeration Technology Department of Refrigeration and Low Temperature EngineeringTianjin University of CommerceTianjin300134China Jiangsu Yongzhiyu Technology Development Co. Ltd.Xuzhou221700China Shandong Onar Refrigeration Technology Co. Ltd.Binzhou256600China

The current study focuses on spray cooling applied to the heat exchange components of a cooling *** optimization of such processes is attempted by assessing different spray flow rates and droplet *** simplicity,the heat exchanger of the cooling tower is modeled as a horizontal round tube and a cooling tower spray cooling model is developed accordingly using a computational fluid dynamics(CFD)*** study examines the influence of varying spray flow rates and droplet sizes on the heat flow intensity between the liquid layer on the surface of the cylindrical tube and the surrounding air,taking into account the number of *** is observed that on increasing the spray flow strength,the heat flow intensity and extent of the liquid film in the system are enhanced ***,the magnitude of droplet size significantly impacts heat transfer.A larger droplet size decreases evaporation in the air and enhances the deposition of droplets on the round *** facilitates the creation of the liquid film and enhances the passage of heat between the liquid film and *** the number of nozzles,while maintaining a constant spray flow rate,results in a decrease in the flow rate of each individual *** decrease is not favorable in terms of heat transfer.

关键词： Spray cooling droplet sizes number of nozzles CFD

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Advances and clinical applications of immune checkpoint inhibitors in hematological malignancies

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Cancer Communications 2024年第9期44卷 1071-1097页

作者： Wenyue sun Shunfeng hu Xin Wang Department of Hematology Shandong Provincial HospitalShandong UniversityJinanShandongP.R.China Department of Hematology Shandong Provincial Hospital Affiliated to Shandong First Medical UniversityJinanShandongP.R.China Taishan Scholars Program of Shandong Province JinanShandongP.R.China Branch of National Clinical Research Center for Hematologic Diseases JinanShandongP.R.China National Clinical Research Center for Hematologic Diseases the First Affiliated Hospital of Soochow UniversitySuzhouJiangsuP.R.China

Immune checkpoints are differentially expressed on various immune cells to regulate immune responses in tumor *** cells can activate the immune checkpoint pathway to establish an immunosuppressive tumor microenvironment and inhibit the anti-tumor immune response,which may lead to tumor progression by evading immune *** coinhibitory signaling pathways with immune checkpoint inhibitors(ICIs)could reinvigorate the anti-tumor immune response and promote immune-mediated eradication of tumor *** a milestone in tumor treatment,ICIs have been firstly used in solid tumors and subsequently expanded to hematological malignancies,which are in their ***,immune checkpoints have been investigated as promising biomarkers and therapeutic targets in hematological malignancies,and novel immune checkpoints,such as signal regulatory proteinα(SIRPα)and tumor necrosis factor-alpha-inducible protein 8-like 2(TIPE2),are constantly being *** ICIs have received clinical approval for clinical application in the treatment of hematological malignancies,especially when used in combination with other strategies,including oncolytic viruses(OVs),neoantigen vaccines,bispecific antibodies(bsAb),bio-nanomaterials,tumor vaccines,and cytokine-induced killer(CIK)***,the proportion of individuals with hematological malignancies benefiting from ICIs remains lower than expected due to multiple mechanisms of drug resistance and immune-related adverse events(irAEs).Close monitoring and appropriate intervention are needed to mitigate irAEs while using *** review provided a comprehensive overview of immune checkpoints on different immune cells,the latest advances of ICIs and highlighted the clinical applications of immune checkpoints in hematological malignancies,including biomarkers,targets,combination of ICIs with other therapies,mechanisms of resistance to ICIs,and irAEs,which can provide novel insight into the future

关键词： Immune checkpoint hematological malignancies biomarkers therapeutic targets drug resistance

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右美托咪定联合七氟烷吸入麻醉对肝癌患者根治术后心功能及胃肠道功能的影响

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成都医学院学报 2024年第4期19卷 649-653页

作者：张春丽徐志新孙虎王文婷海南医学院第二附属医院麻醉科海口570311

目的探究右美托咪定联合七氟烷吸入麻醉对肝癌患者根治术后心功能及胃肠道功能的影响。方法选取2021年1月至2022年7月海南医学院第二附属医院肿瘤科收治的行根治术和淋巴结清扫术治疗的肝癌患者共64例为研究对象,根据随机数字表法随机... 详细信息

目的探究右美托咪定联合七氟烷吸入麻醉对肝癌患者根治术后心功能及胃肠道功能的影响。方法选取2021年1月至2022年7月海南医学院第二附属医院肿瘤科收治的行根治术和淋巴结清扫术治疗的肝癌患者共64例为研究对象,根据随机数字表法随机分为试验组(n=32)和对照组(n=32),对照组患者行丙泊酚麻醉,试验组患者采用右美托咪定联合七氟烷吸入麻醉。记录患者肠道恢复时间、血清肠型脂肪酸结合蛋白(I-FABP)水平等指标及患者不良反应发生情况。结果试验组患者肠鸣音恢复、首次肛门排气、首次自主排便、住院时间均早于对照组(P<0.05),术后2 h I-FABP水平均低于对照组(P<0.05);肠内营养开始时间晚于对照组(P<0.05);T1及T2时,两组患者心率(HR)、每搏输出量(SV)、心输出量(CO)、心脏指数(CI)、左心室舒张末期内径(LVEDD)均较T0降低,且试验组高于对照组(P<0.05),两组左心室射血分数(LVEF)均较T0升高,试验组低于对照组(P<0.05);T3时,两组肌酸磷化酶-同功酶MB(CK-MB)、心肌肌钙蛋白Ⅰ(cTnⅠ)、凝血活酶时间(aPTT)、凝血酶原时间(PT)、凝血酶时间(TT)、纤维蛋白原浓度(Fbg)、血浆血栓素B2(TXB2)、血小板α颗粒膜蛋白(GMP)及血小板最大聚集率(PAGmax)水平均较T0时升高,且试验组患者除PAGmax水平高于对照组外,其余指标均低于对照组(P<0.05);试验组患者不良反应发生率低于对照组(P<0.05)。结论肝癌患者在行根除术治疗中,使用右美托咪定联合七氟烷吸入麻醉能够促进术后肠道功能康复,对心功能保护效果较好。

关键词：原发性肝癌右美托咪定七氟烷心功能胃肠道功能

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《工程测量》课程思政建设与实践探索

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陕西国防职教研究 2024年第1期34卷 9-11,45页

作者：桑丹陈蓉杜祝遥孙虎崔飞飞陕西国防工业职业技术学院陕西西安710300

本文以思政教育及《工程测量》专业课教学为前提,从课程思政建设总体设计、课程目标、教学实践及实践成效等方面,将专业课程中所涉及的思政元素融入到专业课程知识点的教学当中,实现以德育促进智育,将立德树人的根本任务贯穿专业教育教... 详细信息

本文以思政教育及《工程测量》专业课教学为前提,从课程思政建设总体设计、课程目标、教学实践及实践成效等方面,将专业课程中所涉及的思政元素融入到专业课程知识点的教学当中,实现以德育促进智育,将立德树人的根本任务贯穿专业教育教学的全过程。

关键词：工程测量课程思政建设实践

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Natural products from untapped sources as a potent reserve against antimicrobial resistance crisis

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Chinese Journal of Natural Medicines 2024年第7期22卷 577-579页

作者： GU Xiaoxia sun Weiguang hu Zhengxi hubei Key Laboratory of Natural Medicinal Chemistry and Resource Evaluation School of PharmacyTongji Medical CollegeHuazhong University of Science and TechnologyWuhan 430030China

Since the discovery of penicillin in 1928,antibiotics have revolutionized modern medicine by effectively treating infectious diseases and saving countless ***,the widespread development of antimicrobial resistance(AMR)now threatens the efficacy and longevity of these critical drugs.A study published in The Lancet reported that bacterial AMR contributed to approximately 4.95 million deaths globally in 2019,with 1.27 million directly attributable to AMR(Fig.1)[1].Natural products(NPs)continue to play a crucial role in discovering new antibiotics.

关键词： Natural products Untapped sources Antimicrobial resistance

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AN EFFICIENT SCHEDULING ALGORITHM FOR INPUT-QUEUED SWITCHES

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Journal of Electronics(China) 2007年第2期24卷 251-256页

作者： hu Qingsheng sun Yuan Han Jiangtao Institute of Radio Frequency ＆ Optical Electronic ICs Southeast University Nanjing 210096 China

This letter presents an efficient scheduling algorithm DTRR (Dual-Threshold Round Robin) for input-queued switches. In DTRR, a new matched input and output by round robin in a cell time will be locked by two self-adaptive thresholds whenever the queue length or the wait-time of the head cell in the corresponding Virtual Output Queue (VOQ) exceeds the thresholds. The locked input and output will be matched directly in the succeeding cell time until they are unlocked. By employing queue length and wait-time thresholds which are updated every cell time simultane- ously, DTRR achieves a good tradeoff between the performance and hardware complexity. Simula- tion results indicate that the delay performance of DTRR is competitive compared to other typical scheduling algorithms under various traffic patterns especially under diagonal traffic.

关键词： Input Queuing (IQ) switches Scheduling algorithm Threshold

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