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Recent Progress on Aeroelasticity of High-Performance Morphing UAVs

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Computer Modeling in Engineering & Sciences 2022年第10期133卷 1-29页

作者： Binbin Lv jun zha Kaichun Zeng Hongtao guo Li Yu Peng zha.g Institute of High Speed Aerodynamics China Aerodynamics Research and Development CenterMianyang621000China

The high-performance morphing aircraft has become a research focus all over the *** morphing aircraft,unlike regular unmanned aerial vehicles(UAVs),has more complicated aerodynamic characteristics,making itmore difficultto conduct its design,model analysis,and *** paper reviews the recent process and the current status of aeroelastic issues,numerical simulations,and wind tunnel test of morphing *** evaluation of aerodynamic characteristics,mechanism,and relevant unsteady dynamic aerodynamicmodeling throughout the morphing process are the primary technological bottlenecks formorphing *** unstable aerodynamic forces have a significant impact on the aircraft handling characteristics,control law design,and flight *** the past,the structural analysis of morphing aircrafts,flight dynamics modeling,computational mesh morphing technology,and aerodynamic calculation were performed in promoting the development of next generation UAVs,with nonlinear dynamic challenges includingtransonic aeroelastic problems and high angle of attack aeroelastic *** present,many facets of these difficulties,together with the accompanying numerical simulation studies,remain *** addition,wind tunnel experiments face significant challenges in the dynamic morphing ***,dynamic unsteady aerodynamic characteristics in the continuous morphing process still need to be verified by more related experiments.

关键词： Morphing aircraft aeroelasticity numerical simulation wind tunnel test

等离子体处理制备柔性低损耗ABS/Ag太赫兹空芯波导及其传输可靠性研究

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红外与毫米波学报 2024年第4期43卷 533-540页

作者：刘晟沈圆杰侯广宁查志鹏朱怡臻余烁颖张擎天赵强刘少华敬承斌褚君浩华东师范大学物理与电子科学学院纳光电集成与先进装备教育部工程研究中心上海200241

等离子体处理ABS管提升了ABS/Ag镀层太赫兹空芯波导的性能。胶带法测试结果表明,等离子体处理后,银镀层的附着力由5级提升至2级。等离子体处理后的ABS管内表面银层的均匀性和致密度更高,高质量的银层有利于降低波导的损耗。未经等离子... 详细信息

等离子体处理ABS管提升了ABS/Ag镀层太赫兹空芯波导的性能。胶带法测试结果表明,等离子体处理后,银镀层的附着力由5级提升至2级。等离子体处理后的ABS管内表面银层的均匀性和致密度更高,高质量的银层有利于降低波导的损耗。未经等离子体处理的4.2 mm内径的ABS/Ag镀层空芯波导在0.3 THz和0.1 THz时的直线损耗分别为0.72 dB/m和1.47 dB/m,等离子体处理后其损耗分别降至0.70 dB/m和1.44 dB/m,且波导能够在冷热环境中稳定传输太赫兹波。等离子体处理后的样品在超过200小时的湿热老化和16次的高低温循环老化试验后直线损耗升高小于0.1 dB/m,而未经等离子体处理的样品的损耗升高大于1 dB/m。研究结果表明,等离子体处理后的ABS/Ag镀层太赫兹空芯波导损耗更低、传输可靠性更高、耐老化性更好,可用于构建下一代通信、传感及太赫兹成像系统等。

关键词：太赫兹传输太赫兹波导空芯波导等离子体处理

Improved thermoelectric properties of zone-melted p-type bismuth-telluride-based alloys for power generation

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Rare Metals 2022年第5期41卷 1490-1495页

作者： Ren-Shuang zhai Tie-jun Zhu State Key Laboratory of Silicon Materials School of Materials Science and EngineeringZhejiang University.Hangzhou 310027China Thermoelectricity Technology Center Hangzhou Dahe Thermo-Magnetics Co.LtdHangzhou 310053China

Zone-melted bismuth-telluride-based alloys(ZM-BT) are extensively applied to manufacture commercial thermoelectric power generators(TEg). Optimizing the average figure of merit(zT) during 300–500 K of ZM-BT is favora... 详细信息

关键词： alloys bismuth power

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肝脏淋巴管瘤1例并文献复习

中国临床医学影像杂志 2024年第8期35卷 592-593页

作者：查以密吴丽佳郑紫涵明丽香许俊锋大理大学第一附属医院放射影像科云南大理671000

原发性肝淋巴管瘤罕见,其临床及影像学表现无特异性,需病理确诊。本文报道原发性肝淋巴管瘤1例并文献复习,提高对该病的认识病例女,50岁,体检超声发现“多囊肝”14年,为求进一步诊治来我院。实验室检查:白细胞4.78×10^(9)L^(-1),中性... 详细信息

原发性肝淋巴管瘤罕见,其临床及影像学表现无特异性,需病理确诊。本文报道原发性肝淋巴管瘤1例并文献复习,提高对该病的认识病例女,50岁,体检超声发现“多囊肝”14年,为求进一步诊治来我院。实验室检查:白细胞4.78×10^(9)L^(-1),中性粒细胞百分比74%,ALT17U/L,AST19U/L。腹部CT平扫+增强扫描:平扫(图1)肝脏多发大小不等的囊状低密度影,边界清,肝右叶多囊融合,其内可见粗细不均的分隔,部分分隔可见结节状钙化,肝右叶最大囊灶最大截面约9.3cm×6.9cm,CT值约15HU,邻近大囊CT值约10HU。

关键词：淋巴管瘤肝肿瘤体层摄影术,X线计算机

Residual field suppression for magnetocardiography measurement inside a thin magnetically shielded room using bi-planar coil

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Chinese Physics B 2022年第7期31卷 229-234页

作者： Kang Yang Hong-Wei zha.g Qian-Nian zha.g jun-jun zha Deng-Chao Huang College of Electrical Engineering Anhui Polytechnic UniversityWuhu 241000China Key Laboratory of Advanced Perception and Intelligent Control of High-end Equipment Ministry of EducationAnhui Polytechnic UniversityWuhu 241000China

For a magnetocardiography(MCg)system inside a magnetically shielded room(MSR),the residual field should be further suppressed to obtain high-quality MCg *** this paper,a compensation system has been developed based on the bi-planar coil and the proportional-integral-derivative(PID)*** bi-planar coil,derived from the target-field theory and the Tikhonov regularization method,is utilized to generate magnetic field with high uniformity in the predefined target *** the PID controller is introduced to provide dynamic compensation current for the coil,according to the residual field change monitored by a reference SQUID *** measurement results show that the noise suppression ratio(NSR)can reach above 20 dB in the low-frequency range from 0.1 Hz to 50 *** DC component and the fluctuation of the residual field in time-domain can be respectively suppressed to 0 p T and 4 p T,indicating that this proposed compensation method is useful for the MCg measurement.

关键词： SQUID magnetocardiography bi-planar coil active compensation

学龄前儿童体质量指数和视屏暴露与执行功能的关联

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中国学校卫生 2024年第8期45卷 1111-1114,1119页

作者：周杨李若瑜查金红吴峻万宇辉黄永玲安徽医科大学公共卫生学院健康促进与行为科学系合肥230032 安徽医科大学公共卫生学院儿少卫生与妇幼保健学系安徽省妇女儿童保健中心儿童保健科

目的分析安徽省学龄前儿童体质量指数(BMI)、学习/游戏视屏暴露与执行功能的关联,为促进学龄前儿童执行功能发展提供依据。方法于2022年6月,采用分层整群抽样与方便抽样相结合的方法对安徽省芜湖市、六安市和阜阳市3534名学龄前儿童母... 详细信息

目的分析安徽省学龄前儿童体质量指数(BMI)、学习/游戏视屏暴露与执行功能的关联,为促进学龄前儿童执行功能发展提供依据。方法于2022年6月,采用分层整群抽样与方便抽样相结合的方法对安徽省芜湖市、六安市和阜阳市3534名学龄前儿童母亲进行问卷调查,采用执行功能行为评定问卷(BRIEF-P)调查学龄前儿童执行功能异常状况,使用二元Logistic回归分析儿童BMI、学习/游戏视屏暴露及其联合作用与执行功能异常的关联。结果学龄前儿童执行功能异常检出率为9.65%。Logistic回归模型分析显示,在调整母亲妊娠期高血压、主要照料人、家庭人均月收入和家庭结构等混杂因素后,超重肥胖组、高学习/游戏视屏暴露组儿童执行功能异常风险显著增加(超重肥胖:OR=1.78,95%CI=1.31~2.42;学习视屏暴露:OR=1.48,95%CI=1.18~1.86;游戏视屏暴露:OR=1.50,95%CI=1.18~1.91,P值均<0.05)。与BMI正常且低学习/游戏视屏暴露组相比,超重肥胖且高学习/游戏视屏暴露组发生执行功能异常风险显著增加(OR=2.07,95%CI=1.29~3.31;OR=2.42,95%CI=1.59~3.68,P值均<0.05)。结论超重肥胖和高学习/游戏视屏暴露是学龄前儿童执行功能异常症状的重要危险因素,应积极引导学龄前儿童养成良好的生活习惯以促进执行功能正常发展。

关键词：人体质量指数注视,眼执行功能回归分析儿童,学龄前

杨骏教授基于疾病要素针灸综合治疗神经性耳鸣经验

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中国针灸 2024年第10期44卷 1172-1176页

作者：张乐乐袁爱红叶敏解鸿宇张雅婷查必祥戎志豪杨骏安徽中医药大学安徽中医药大学第一附属医院针灸康复科

杨骏教授从中医经典出发，结合临床经验和现代研究发现，深入分析神经性耳鸣的病因病机，总结出其中医疾病要素——气滞血瘀，神匿窍闭。综合针刺、电针、温针灸、冰片灸和中药多种治疗手段，妙用听宫，重用哑门，多穴配伍，多法并举，... 详细信息

杨骏教授从中医经典出发，结合临床经验和现代研究发现，深入分析神经性耳鸣的病因病机，总结出其中医疾病要素——气滞血瘀，神匿窍闭。综合针刺、电针、温针灸、冰片灸和中药多种治疗手段，妙用听宫，重用哑门，多穴配伍，多法并举，各取所宜，量效叠加，共奏活血通络、宁神开窍之功，竭力提高针灸疗效。

关键词：神经性耳鸣针灸疾病要素名医经验杨骏

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复合粘结剂对Fe-MOF衍生催化剂组装锌空电池稳定性影响研究

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化学研究与应用 2024年第3期36卷 616-622页

作者：金虹苏强查国君周来宏黄平江民华丁海峰新余学院新能源科学与工程学院江西新余338004

作为锌空电池阴极催化剂之一,新型Fe-MOF基催化剂相对于商业化的Pt/C+RuO_(2)催化剂来说,不仅价格低廉、比电容高,而且具有双功能催化活性,受到锌空电池研究人员的关注。为了提升Fe-MOF衍生催化剂锌空电池长期运行稳定性,本研究通过优... 详细信息

作为锌空电池阴极催化剂之一,新型Fe-MOF基催化剂相对于商业化的Pt/C+RuO_(2)催化剂来说,不仅价格低廉、比电容高,而且具有双功能催化活性,受到锌空电池研究人员的关注。为了提升Fe-MOF衍生催化剂锌空电池长期运行稳定性,本研究通过优化催化层粘结剂组成和制备工艺,制备组装FeMOF-5%PTN-H锌空电池,并与传统Nafion粘结剂组装电池进行性能比较,分析锌空电池长时间充放电循环电化学稳定性提升机制。研究表明,经过长时间充放电循环测试,5%PTN-H复合粘结剂可以有效抑制Fe-MOF催化层脱落,较好地保持了催化剂粒子原有的结构。充放电循环后,FeMOF-5%PTN-H所组装的电池峰功率密度衰减率为2.3%,仅为FeMOF-N组装电池衰减率(44%)的5.3%。由此可见,5%PTN-H复合粘结剂可以有效提升FeMOF衍生催化剂组装锌空电池长期运行稳定性。本研究从材料构效关系角度,分析了催化层粘结剂对电池稳定性的影响机制,为深入理解和优化改进锌空电池长期运行状态具有重要参考意义。

关键词： Fe-MOF衍生催化剂锌空电池 PTFE 稳定性

Numerical simulation of rock-breaking and influence laws of dynamic load parameters during axial-torsional coupled impact drilling with a single PDC cutter

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Petroleum Science 2023年第3期20卷 1806-1827页

作者： Yan Xi Hao-Yu Wang Chun-Qing zha jun Li gong-Hui Liu Bo-Yun guo Beijing University of Technology Bejing100124China China University of Petroleum-Bejing Beijing102249China China University of Petroleum-Beijing at Karamay KaramayXinjiang834000China University of Louisiana at Lafayett Lafayette70504USA

Axial and torsional impact drilling technology is used to improve the drilling efficiency of hard rock formation in the deep ***,the corresponding theory is not mature,and there are few correlative research reports on the rock-breaking mechanism of axial and torsional coupled impact drilling *** the influence of the impact hammer geometry and movement on the dynamic load parameters(i.e.,wavelength,amplitude,frequency,and phase difference),a numerical model that includes a hard formation and single polycrystalline diamond compact cutter was *** Riedel-Hiermaier-Thoma model,which considers the dynamic damage and strength behavior of rocks,was adopted to analyze the rock damage under axial and torsional impact *** numerical simu-lation results were verified by the experimental *** was found that compared with conventional drilling,the penetration depths of axial,torsional,and axial-torsional coupled impact drilling increased by 31.3%,5.6%,and 34.7%,*** the wavelength and amplitude of the axial impact stress wave improved the penetration *** the bit rotation speed remained unchanged,increasing the frequency in the axial and circumferential directions had little effect on the penetration ***,as the frequency increased,the cutting surface became increasingly smooth,which reduced the occurrence of bit *** the phase difference between the axial and circumfer-ential stress waves was 25%,the penetration depth significantly *** addition,the bit vibration problem can be effectively ***,the adjustment of engineering and tool structure parameters is proposed to optimize the efficiency of the axial-torsional coupled impact drilling tool.

关键词： Axial-torsional coupled impact drilling tool Rock-breaking PDC cutter RHT model