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Theory of Flexural Shear, Bending and Torsion for a Thin-Walled Beam of Open Section
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作者 David W. A. Rees Abdelraouf M. Sami Alsheikh 《World Journal of Mechanics》 2024年第3期23-53,共31页
Aspects of the general Vlasov theory are examined separately as applied to a thin-walled channel section cantilever beam under free-end end loading. In particular, the flexural bending and shear that arise under trans... Aspects of the general Vlasov theory are examined separately as applied to a thin-walled channel section cantilever beam under free-end end loading. In particular, the flexural bending and shear that arise under transverse shear and axial torsional loading are each considered theoretically. These analyses involve the location of the shear centre at which transverse shear forces when applied do not produce torsion. This centre, when taken to be coincident with the centre of twist implies an equivalent reciprocal behaviour. That is, an axial torsion applied concentric with the shear centre will twist but not bend the beam. The respective bending and shear stress conversions are derived for each action applied to three aluminium alloy extruded channel sections mounted as cantilevers with a horizontal principal axis of symmetry. Bending and shear are considered more generally for other thin-walled sections when the transverse loading axes at the shear centre are not parallel to the section = s centroidal axes of principal second moments of area. The fixing at one end of the cantilever modifies the St Venant free angular twist and the free warping displacement. It is shown from the Wagner-Kappus torsion theory how the end constrained warping generates an axial stress distribution that varies with the length and across the cross-section for an axial torsion applied to the shear centre. It should be mentioned here for wider applications and validation of the Vlasov theory that attendant papers are to consider in detail bending and torsional loadings applied to other axes through each of the centroid and the web centre. Therein, both bending and twisting arise from transverse shear and axial torsion applied to each position being displaced from the shear centre. Here, the influence of the axis position upon the net axial and shear stress distributions is to be established. That is, the net axial stress from axial torsional loading is identified with the sum of axial stress due to bending and axial stress arising from constrained warping displacements at the fixing. The net shear stress distribution overlays the distributions from axial torsion and that from flexural shear under transverse loading. Both arise when transverse forces are displaced from the shear centre. 展开更多
关键词 Thin Wall Theory Cantilever Beam Open Channel Section Principal Axes Flexure Transverse Shear TORSION Shear Centre Shear Flow WARPING Fixed-end Constraint
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回归与发展——Blending Learning下对信息技术教育应用发展方向的几点思考 被引量:2
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作者 张勇强 张世禄 马莉 《现代远距离教育》 CSSCI 2006年第5期63-64,共2页
本文从Blending Learning新涵义的角度思考,教学因素的重要组成部分之一———信息技术教育应用,在这场历史性的大变革中应何去何从?并从信息技术教育应用的发展历程,信息技术教育应用的现状分析,Blending Learning下的信息技术教育应... 本文从Blending Learning新涵义的角度思考,教学因素的重要组成部分之一———信息技术教育应用,在这场历史性的大变革中应何去何从?并从信息技术教育应用的发展历程,信息技术教育应用的现状分析,Blending Learning下的信息技术教育应用以及信息技术与课堂教学的有效整合四个方面加以阐述。 展开更多
关键词 B1ending LEARNING 信息技术教育应用 信息技术与课堂整舍
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A Good Beginning and Ending Highlight a Speech
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作者 曾艳山 刘诺亚 《海外英语》 2012年第6X期126-127,共2页
A good beginning grasps the audience's attention,arouses their interest,and presents the gist of your speech,while a good ending reinforces your stance,creates a sense of completeness and leaves the listeners spac... A good beginning grasps the audience's attention,arouses their interest,and presents the gist of your speech,while a good ending reinforces your stance,creates a sense of completeness and leaves the listeners space for further thinking. 展开更多
关键词 BEGINNING ending SPEECH TIP
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精液优化处理后DNA碎片指数与IVF-ET胚胎质量及妊娠结局的关系
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作者 杨洪毅 刘艳 +2 位作者 许宁 李刚 金海霞 《郑州大学学报(医学版)》 CAS 北大核心 2024年第5期664-668,共5页
目的:评估经密度梯度离心联合上游法优化处理后的精子DNA碎片指数(DFI)与辅助生殖体外受精-胚胎移植(IVF-ET)胚胎质量及妊娠结局的关系。方法:回顾性分析2022年4月至12月在郑州大学第一附属医院生殖医学中心因单纯输卵管因素行IVF-ET的... 目的:评估经密度梯度离心联合上游法优化处理后的精子DNA碎片指数(DFI)与辅助生殖体外受精-胚胎移植(IVF-ET)胚胎质量及妊娠结局的关系。方法:回顾性分析2022年4月至12月在郑州大学第一附属医院生殖医学中心因单纯输卵管因素行IVF-ET的257个周期,比较男方精液优化前后精液参数和精子DFI;按优化后精子DFI将其分为高DFI组(DFI>5)与低DFI组(DFI≤5),比较两组的胚胎发育及妊娠结局;根据临床妊娠情况分为妊娠组与非妊娠组、持续妊娠组及早期流产组,比较精子DFI情况。结果:与处理前相比,精液优化处理后前向运动精子及正常形态精子百分比提高,精子DFI下降(P<0.001)。精子优化处理后高DFI组的早期流产率高于低DFI组(P<0.05)。105例临床妊娠周期中早期流产组精液优化处理前、后DFI均高于持续妊娠组(P<0.05)。结论:密度梯度离心联合上游优化处理是一种有效的精液制备方法,可提高精子前向运动能力和正常形态精子比例,降低精子DFI;优化后精子高DFI可能增加临床妊娠后早期流产的风险。 展开更多
关键词 精子DNA碎片指数 密度梯度离心联合上游法 ivf-et 胚胎质量 妊娠结局
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Coupled bending-torsion vibration of a homogeneous beam with a single delamination subjected to axial loads and static end moments 被引量:1
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作者 Yang Liu Dong-Wei Shu 《Acta Mechanica Sinica》 SCIE EI CAS CSCD 2014年第4期607-614,共8页
Delaminations in structures may significantly reduce the stiffness and strength of the structures and may affect their vibration characteristics. As structural components, beams have been used for various purposes, in... Delaminations in structures may significantly reduce the stiffness and strength of the structures and may affect their vibration characteristics. As structural components, beams have been used for various purposes, in many of which beams are often subjected to axial loads and static end moments. In the present study, an analytical solution is developed to study the coupled bending-torsion vibration of a homogeneous beam with a single delamination subjected to axial loads and static end moments. Euler-Bernoulli beam theory and the "free mode" assumption in delamination vibration are adopted. This is the first study of the influences of static end moments upon the effects of delaminations on natural frequencies, critical buckling loads and critical moments for lateral instability. The results show that the effects of delamination on reducing natural frequencies, critical buckling load and critical moment for lateral instability are aggravated by the presence of static end moment. In turn, the effects of static end moments on vibration and instability characteristics are affected by the presence of delamination. The analytical results of this study can serve as a benchmark for finite element method and other numerical solutions. 展开更多
关键词 Vibration · Delamination ·end moments · Nat-ural frequency · Critical moment for lateral instability
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A mathematics model investigation of ideal fluids in a pipeline of moving ending 被引量:4
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作者 陈彬 易孟林 《Journal of Harbin Institute of Technology(New Series)》 EI CAS 2007年第2期259-262,共4页
A case of ideal fluid flow in a moving ending rigid constant diameter circular pipeline is investigated. A model of the pipeline was established based on distributed-parameter theory. The comparisons on a quotient mod... A case of ideal fluid flow in a moving ending rigid constant diameter circular pipeline is investigated. A model of the pipeline was established based on distributed-parameter theory. The comparisons on a quotient module of output and input pressure of the moving ending model and neglected ending moving model are made on the frequency response. It is revealed that the moving ending of pipeline influences largely the quotient amplitude of output and input pressure, and the peak value of frequency resonance increases with the increase of pipeline’s length. 展开更多
关键词 a pipeline of moving ending distributed-parameter model the quotient amplitude of output and input pressure the peak value of frequency resonance
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不孕症患者IVF-ET助孕后自然流产的相关因素分析
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作者 姜璎钊 邹雅琴 +1 位作者 屈艳阳 陈洁 《生殖医学杂志》 CAS 2024年第10期1346-1350,共5页
目的分析不孕症患者IVF-ET助孕后自然流产的相关因素。方法回顾性分析2022年7月至2023年6月在中国医学科学院北京协和医院首次接受IVF-ET助孕并临床妊娠的357例不孕症患者的临床资料,按照是否出现自然流产情况分为未流产组(n=312)和流产... 目的分析不孕症患者IVF-ET助孕后自然流产的相关因素。方法回顾性分析2022年7月至2023年6月在中国医学科学院北京协和医院首次接受IVF-ET助孕并临床妊娠的357例不孕症患者的临床资料,按照是否出现自然流产情况分为未流产组(n=312)和流产组(n=45),比较两组患者的基础临床资料、男方精液参数、疾病史/既往史、IVF-ET相关资料等临床资料,基于Logistic回归模型分析自然流产的相关因素。结果应用Logistic回归模型分析发现,年龄≥35岁、体质量指数(BMI)>24 kg/m^(2)、男方精子活力为D级、男方精子浓度≤15×10^(6)/ml、男方精子DNA碎片指数>20%、人工流产史>3次、自然流产史>3次、宫腔操作史>2次、有子宫肌瘤患病史、移植胚胎质量为C级是不孕症患者IVF-ET后自然流产的危险因素(OR>1,P<0.05)。结论不孕症患者的年龄大、BMI高、人工/自然流产次数多、宫腔操作次数多、有子宫肌瘤患病史和移植胚胎质量差可增加IVF-ET助孕后自然流产的风险,且男方精子活力差、浓度低和男方精子DNA碎片指数大也会加大IVF-ET后自然流产的风险。 展开更多
关键词 不孕症 ivf-et 自然流产 相关因素 LOGISTIC回归模型
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1例遗传性易栓症患者行IVF-ET助孕治疗的护理
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作者 郑湘琼 吴嘉齐 +3 位作者 马肇华 柯玩娜 吕燕君 李庆妮 《当代护士(上旬刊)》 2024年第1期113-116,共4页
总结1例遗传性易栓症患者行IVF-ET助孕治疗的护理经验。护理要点包括静脉血栓风险评估、健康教育、预防护理、皮肤管理、加强心理支持、延续性护理等。经过精心的治疗及护理后,患者在IVF-ET助孕治疗过程中未发生静脉血栓栓塞。
关键词 遗传性易栓症 ivf-et助孕 护理
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Fracture Healing in a Denervation and/or Nerve Ending Interpositioning Model in the Rat
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作者 Cagri Yegengil Mahmut Pekedis Hasan Yildiz 《International Journal of Clinical Medicine》 2011年第3期301-306,共6页
Background: In this experimental study, we aimed to determine the possible changes in fracture healing due to denervation and/or nerve ending interpositioning. Methods: 50 Wistar Albino type male rats were divided int... Background: In this experimental study, we aimed to determine the possible changes in fracture healing due to denervation and/or nerve ending interpositioning. Methods: 50 Wistar Albino type male rats were divided into three study groups. A standard transverse diaphysial fracture in the femurs of the same side of all subjects under anesthesia was created and the fracture were fixed intramedullarily. While preserving the structural integrity of the sciatic nerve in the first group, neurectomy to the nerve in the second group was performed. In the third group, following the sciatic nerve cut, the proximal end of the nerve were interposed the fracture line. After a 28-day observational period, the callus formation in the subjects was examined radiologically, biomechanically and histopathologically. Results: Among all groups, the third group subjects showed significant increase in radiological area measurements when they are compared to the second group rats. There was no significant difference in biomechanical measurements of fractured femurs of the three groups. In histopathological evaluations, it was observed that denervation had increased the thickness of the cartilage and the number of the chondrocytes and osteoclasts significantly but decreased the number of fibroblasts compared to the control group. In addition to the denervation nerve ending interpositioning increased the bone thickness and the number of the osteoblasts but decreased the number of the osteoclasts significantly. Conclusions: While radiological observations exhibit that nerve ending interpositioning has resulted more hypertrophic callus formation, histopathological evaluations led us to that denervation created partial (immature) callus formation and nerve ending interpositioning demonstrated larger but immature callus formation. 展开更多
关键词 DENERVATION NERVE ending INTERPOSITION Fracture HEALING CALLUS Formation
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O. Henry-Style Ending and Its Influence
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作者 WANG Zhe 《Sino-US English Teaching》 2020年第6期198-202,共5页
The writer O.Henry was famous for surprising endings,which is a common feature of his short stories.They have original plots and usually end in a way that you can never imagine.Because of his humorous language,his uni... The writer O.Henry was famous for surprising endings,which is a common feature of his short stories.They have original plots and usually end in a way that you can never imagine.Because of his humorous language,his unique narrative skills,and his unexpected and reasonable ending,O.Henry got a high reputation.His execllent technique of writng is more obvious for the irony of reality and the return of human nature.The O.Henry-style ending opened up the pluralistic development of later realistic literature.The highly critical ending of its turning point also promotes the practical significance of the reaction of world literature to society. 展开更多
关键词 the features of O.Henry-style endings the functions of O.Henry-style endings the influence of O.Henry-style endings
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Out of Absurdity On the Ending of Catch-22
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作者 YE La-mei 《Journal of Literature and Art Studies》 2014年第6期423-435,共13页
As one of the first and most original creations of literary postmodernism, published in the year 1961, Catch-22's (1961) position in American literature remains secure. Yet its ending has been held as unconvincing ... As one of the first and most original creations of literary postmodernism, published in the year 1961, Catch-22's (1961) position in American literature remains secure. Yet its ending has been held as unconvincing ever since its publication. Taking the overall structure, tone, and the theme of the novel into consideration, this paper aims to prove the credibility of this controversial part. It consists of five sections apart from an introduction and a conclusion. Section One provides general information on the life and works of Joseph Heller. Section Two traces the impact of existentialism and the generation of black humor to clarify the literary position of Catch-22. Section Three brings out the disputative opinions on the ending part. Sections Four and Five, try to prove Yossarian's final desertion a natural and convincing ending from different perspectives: Section Four analyses how Yossarian gains an entropic vision of the cosmos; section Five studies his existential vision of physical life and searches for the immediate factors that propel Yossarian's desertion. Section five also explains the ending's change in tone and structure. The conclusion summarizes the paper and points out the social significance of the novel. 展开更多
关键词 ABSURDITY CATCH-22 the ending
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Methylation reactions at dopaminergic nerve endings, serving as biological off-switches in managing dopaminergic functions
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作者 Clivel G.Charlton 《Neural Regeneration Research》 SCIE CAS CSCD 2014年第11期1110-1111,共2页
The mechanisms for the regulation of synaptic dopamine (DA) include its release from presynaptic vesicles, its interaction with post-synaptic and pre-synaptic DA receptors, the reuptake of DA, via dopamine transport... The mechanisms for the regulation of synaptic dopamine (DA) include its release from presynaptic vesicles, its interaction with post-synaptic and pre-synaptic DA receptors, the reuptake of DA, via dopamine transporter (DAT), the diffusion of DA and its metabolism by mono-amine oxidase (MAO) and cate- chol-O-methyl transferase (COMT). DA controls complex and specialized functions including, movements, behavior, mood, perception, reward, and more recently, neurogenesis (Popolo et al., 2004; Reimer et al., 2013) and neuroregeneration (Hoglinger et al., 2004; Yang et al., 2008). These functions are varied and of high fidelity. Movement, as an example, requires regulatory mechanisms for initiating, stopping, slowing-down speed- ing-up, changing directions, for governing the relentless urges to move in the young and sedentariness in the old as well as in motor-freezing, catalepsy, tremor and stereotypy. 展开更多
关键词 DAT serving as biological off-switches in managing dopaminergic functions Methylation reactions at dopaminergic nerve endings COMT
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On Sarah's Final Freedom-Interpretation of the last ending of The French Lieutenant's woman
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作者 彭美容 《海外英语》 2013年第15期194-195,197,共3页
The French Lieutenant's Woman is the best-known novel written by John Fowles and is also called the post-modern metafiction.In the novel the mysterious woman Sarah is introduced,who rebels against Victorian conven... The French Lieutenant's Woman is the best-known novel written by John Fowles and is also called the post-modern metafiction.In the novel the mysterious woman Sarah is introduced,who rebels against Victorian conventions to pursue independence and freedom.Undoubtedly,Sarah is an independent woman ahead of her times.This paper is attempted to interpret the last ending of The French Lieutenant's woman written by John Fowles,thus finding relevant evidence to support this interpretation that Sarah has finally got her freedom which is not allowed against the Victorian background. 展开更多
关键词 LAST ending FREEDOM VICTORIAN BACKGROUND
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章勤治疗围IVF-ET期经验举隅
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作者 钱海墨 章勤 《浙江中医杂志》 2024年第8期670-671,共2页
介绍章勤对体外受精与胚胎移植(IVF-ET)围手术期中医药调治经验:术前倡导辨病辨证,溯源求因;术中配合西医治疗,中西合璧;移植之际或孕后力求蓝田种玉、固冲安胎。
关键词 ivf-et 中医药疗法 章勤 名医经验
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High glucose reduces Nrf2-dependent cRAGE release and enhances inflammasome-dependent IL-1βproduction in monocytes:the modulatory effects of EGCG 被引量:1
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作者 Chi-Hao Wu Yin-Hsuan Chang +2 位作者 Chin-Lin Hsu Sheng-Yi Chen Gow-Chin Yen 《Food Science and Human Wellness》 SCIE CSCD 2024年第3期1531-1542,共12页
Soluble receptor for advanced glycation end products(sRAGE)acts as a decoy sequestering of RAGE ligands,thus preventing the activation of the ligand-RAGE axis linking human diseases.However,the molecular mechanisms un... Soluble receptor for advanced glycation end products(sRAGE)acts as a decoy sequestering of RAGE ligands,thus preventing the activation of the ligand-RAGE axis linking human diseases.However,the molecular mechanisms underlying sRAGE remain unclear.In this study,THP-1 monocytes were cultured in normal glucose(NG,5.5 mmol/L)and high glucose(HG,15 mmol/L)to investigate the effects of diabetesrelevant glucose concentrations on sRAGE and interleukin-1β(IL-1β)secretion.The modulatory effects of epigallocatechin gallate(EGCG)in response to HG challenge were also evaluated.HG enhanced intracellular reactive oxygen species(ROS)generation and RAGE expression.The secretion of sRAGE,including esRAGE and cRAGE,was reduced under HG conditions,together with the downregulation of a disintegrin and metallopeptidase 10(ADAM10)and nuclear factor erythroid 2-related factor 2(Nrf2)nuclear translocation.Mechanistically,the HG effects were counteracted by siRAGE and exacerbated by siNrf2.Chromatin immunoprecipitation results showed that Nrf2 binding to the ADAM10 promoter and HG interfered with this binding.Our data reinforce the notion that RAGE and Nrf2 might be sRAGE-regulating factors.Under HG conditions,the treatment of EGCG reduced ROS generation and RAGE activation.EGCG-stimulated cRAGE release was likely caused by the upregulation of the Nrf2-ADAM10 pathway.EGCG inhibited HG-mediated NLRP3 inflammasome activation at least partly by stimulating sRAGE,thereby reducing IL-1βrelease. 展开更多
关键词 Epigallocatechin gallate(EGCG) INFLAMMASOME Nuclear factor erythroid 2-related factor 2(Nrf2) Receptor for advanced glycation end products(RAGE) Soluble RAGE(sRAGE)
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FE Study for Reducing Forming Forces and Flat End Areas of Cylindrical Shapes Obtained by the Roll-Bending Process
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作者 Quan Hoang Tran Henri Champliaud Zhengkun Feng Thien My Dao 《Journal of Mechanics Engineering and Automation》 2014年第6期467-475,共9页
A roll-bending process that minimizes the flat areas on the leading and trailing ends of formed plates will produce more accurate and easier assemble final shapes. There are several methods of minimizing flat areas, b... A roll-bending process that minimizes the flat areas on the leading and trailing ends of formed plates will produce more accurate and easier assemble final shapes. There are several methods of minimizing flat areas, but they are costly or difficult to apply for thick plates. This study proposes a new, simple approach that reduces these flat areas. This approach includes moving the bottom roll slightly along the feeding direction and adjusting the bottom roll location. Sensitivity analyses were performed using a developed 3D dynamic FE (finite element) model of an asymmetrical roll-bending process in the Ansys/LS-Dyna software package. Simulations were validated by experiments run on an instrumented roll-bending machine. The FE results indicate that this new approach not only minimizes the flat areas but also reduces the forming forces. 展开更多
关键词 Roll-bending process flat end areas dynamic FEM simulation Ansys/LS-Dyna.
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悦享童趣 萌宝总动员——记第一届运通兴宝亲子嘉年华happy ending
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《中国集体经济》 2014年第23期116-117,共2页
10月19日,很多"自强不吸,抗霾到底"的马拉松战士在市区内坚持"北马"比赛。而一些有先见之明的BMW车主潮爸辣妈们则带着宝宝早早集结在北京运通兴宝4S店,应邀前来参加"悦享童趣,萌宝总动员"北京运通兴宝... 10月19日,很多"自强不吸,抗霾到底"的马拉松战士在市区内坚持"北马"比赛。而一些有先见之明的BMW车主潮爸辣妈们则带着宝宝早早集结在北京运通兴宝4S店,应邀前来参加"悦享童趣,萌宝总动员"北京运通兴宝亲子嘉年华,整装待发去往顺义的意大利农场,在各种绿树森林植被的"天然氧吧"环抱下,将可怕雾霾远远甩在身后,与宝宝和其他BMW家庭及运通兴宝的工作人员一起DIY西餐甜点、共享意式美味大餐、游戏竞赛赢取运通兴宝VIP大奖…… 展开更多
关键词 HAPPY 天然氧吧 森林植被 主潮 ending 活动经验 食材 宝精 个性化关怀 舒适感受
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Effect of Bogie Cavity End Wall Inclination on Flow Field and Aerodynamic Noise in the Bogie Region of High-Speed Trains
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作者 Jiawei Shi Jiye Zhang 《Computer Modeling in Engineering & Sciences》 SCIE EI 2024年第5期2175-2195,共21页
Combining the detached eddy simulation(DES)method and Ffowcs Williams-Hawkings(FW-H)equation,the effect of bogie cavity end wall inclination on the flow field and aerodynamic noise in the bogie region is numerically s... Combining the detached eddy simulation(DES)method and Ffowcs Williams-Hawkings(FW-H)equation,the effect of bogie cavity end wall inclination on the flow field and aerodynamic noise in the bogie region is numerically studied.First,the simulation is conducted based on a simplified cavity-bogie model,including five cases with different inclination angles of the front and rear walls of the cavity.By comparing and analyzing the flow field and acoustic results of the five cases,the influence of the regularity and mechanism of the bogie cavity end wall inclination on the flow field and the aerodynamic noise of the bogie region are revealed.Then,the noise reduction strategy determined by the results of the simplified cavity-bogie model is applied to a three-car marshaling train model to verify its effectiveness when applied to the real train.The results reveal that the forward inclination of the cavity front wall enlarges the influence area of shear vortex structures formed at the leading edge of the cavity and intensifies the interaction between the vortex structures and the front wheelset,frontmotor,and front gearbox,resulting in the increase of the aerodynamic noise generated by the bogie itself.The backward inclination of the cavity rear wall is conducive to guiding the vortex structures flow out of the cavity and weakening the interaction between the shear vortex structures and the cavity rear wall,leading to the reduction of the aerodynamic noise generated by the bogie cavity.Inclining the rear end wall of the foremost bogie cavity of the head car is a feasible aerodynamic noise reduction measure for high-speed trains. 展开更多
关键词 BOGIE cavity flow aerodynamic noise end wall inclination
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Happy Ending
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作者 吴非 《大学(指南)》 2010年第1期92-93,共2页
“你看这两个哪个好看?” “都挺好。”尹思洁愎诽,价钱更好看。帮刘芳芳抱着背包,看她拿两条裤子在身上比来比去。
关键词 《Happy ending 散文 吴非 文学作品
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End-group modulation of phenazine based non-fullerene acceptors for efficient organic solar cells with high open-circuit voltage
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作者 Yahui Zhang Yafeng Li +7 位作者 Ruixiang Peng Yi Qiu Jingyu Shi Zhenyu Chen Jinfeng Ge Cuifen Zhang Zheng Tang Ziyi Ge 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2024年第1期461-468,I0011,共9页
Phenazine-based non-fullerene acceptors(NFAs)have demonstrated great potential in improving the power conversion efficiency(PCE)of organic solar cells(OSCs).Halogenation is known to be an effective strategy for increa... Phenazine-based non-fullerene acceptors(NFAs)have demonstrated great potential in improving the power conversion efficiency(PCE)of organic solar cells(OSCs).Halogenation is known to be an effective strategy for increasing optical absorption,refining energy levels,and improving molecular packing in organic semiconductors.Herein,a series of NFAs(Pz IC-4H,Pz IC-4F,Pz IC-4Cl,Pz IC-2Br)with phenazine as the central core and with/without halogen-substituted(dicyanomethylidene)-indan-1-one(IC)as the electron-accepting end group were synthesized,and the effect of end group matched phenazine central unit on the photovoltaic performance was systematically studied.Synergetic photophysical and morphological analyses revealed that the PM6:Pz IC-4F blend involves efficient exciton dissociation,higher charge collection and transfer rates,better crystallinity,and optimal phase separation.Therefore,OSCs based on PM6:Pz IC-4F as the active layer exhibited a PCE of 16.48%with an open circuit voltage(Voc)and energy loss of 0.880 V and 0.53 e V,respectively.Accordingly,this work demonstrated a promising approach by designing phenazine-based NFAs for achieving high-performance OSCs. 展开更多
关键词 Organic solar cells Non-fullerene acceptor PHENAZINE Central core end group
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