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颗粒尺寸及倾角对渗流水压力分布的影响研究

采矿与安全工程学报 2021年第3期38卷 592-601页

作者：韩流舒继森尚涛杨国宇陈涛李胤达 GeRsON s v Tovele 中国矿业大学矿业工程学院江苏徐州221116

为了研究颗粒尺寸及渗流倾角对水压力分布的影响规律,基于水力学基本原理,推导出了结构面渐进贯通过程中的静水压力以及多孔介质连续渗流过程中的渗透力计算方法,揭示了颗粒结构、倾角与水压力的函数关系。设计单因素渗流试验方案,分别... 详细信息

为了研究颗粒尺寸及渗流倾角对水压力分布的影响规律,基于水力学基本原理,推导出了结构面渐进贯通过程中的静水压力以及多孔介质连续渗流过程中的渗透力计算方法,揭示了颗粒结构、倾角与水压力的函数关系。设计单因素渗流试验方案,分别以颗粒尺寸和渗流倾角为自变量,以压力水头为因变量,进行了9组循环渗流试验,测定了沿程压力水头。结果表明:渗透力未改变石子、中沙的颗粒排布结构,造成了细沙渗流路径上13^(#)水头管位置出现流沙沉降。沿程压力水头在石子、中沙内部分别呈"直角三角形"和"等腰三角形"分布,在细沙内部则呈现连续增长+骤降+水平波动+连续下降的分布规律。峰值压力水头分别出现在石子渗流路径的终点、中沙渗流路径的中点,以及细沙压力水头骤降区的起点。石子、中沙渗流的峰值压力水头△h_(max)与β,sinβ均符合良好的线性关系,细沙渗流的峰值压力水头与倾角符合二次函数关系。散体介质过流断面与底板出水孔透水能力的相对大小是决定压力水头峰值和分布规律的关键因素。

关键词：颗粒尺寸倾角渗流试验水压力分布规律

supratentorial dural-based collision of cavernoma and meningioma: a case report

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Chinese Neurosurgical Journal 2018年第3期4卷 162-165页

作者： A.v.Dubovoy v.M.Jafarov e.I.voronina FsBI'Federal Center of Neurosurgery' Ministry of Health Care of the Russian FederationNovosibirskRussian Federation630087 Ministry of Healthcare of the Russian Federation Novosibirsk State Medical UniversityNovosibirskRussian Federation630091

Background: Collision tumor is a very rare case of cerebral lesion. Approximately 50 reports of intracranial collision tumors were described in the literature. We present a case of supratentorial dural-based convexity collision tumor radiologically mimicking cavernous malformation and composed of cavernous malformation and meningioma. Case presentation: The case presents a 63-year-old female having MR findings such as hemorraged supratentorial dural-based mass with 'popcorn' signs and hemosiderin deposits. The patient underwent craniotomy and evacuation of the subdural hematoma with resection of the tumor mass. Histologically the lesion had signs of a cavernoma and meningioma. MRI in a year after surgery did not reveale residual tumor mass or recurrence. Conclusions: Collision tumor is a very rare case. Preoperative diagnosis of a dural lesion is difficult and challenging. A neuroradiological differential diagnosis of similar cases needs focused attention.

关键词： Cavernous malformation Cavernous hemangioma Cavernous angioma Meningioma Convexity tumor Collision tumor Dural lesion

Joining of AZ91 Mg alloy and Al6063 alloy sheets by friction stir welding

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Journal of Magnesium and Alloys 2018年第1期6卷 71-76页

作者： B.Lakshmana Prasad G.Neelaiah M.Gopi Krishna s.v.v.Ramana K.sai Prakash G.sarika G.Pradeep Kumar Reddy Ravikumar Dumpala B.Ratna sunil Department of Mechanical engineering Rajiv Gandhi University of Knowledge Technologies(AP-IIIT)Nuzvid 520201India Department of Mechanical engineering Vignana Bharathi Institute of TechnologyHyderabad 501301India Department of Mechanical engineering Visvesvaraya National Institute of TechnologyNagpur 440010India

In the present work,the effect of process parameters on joining of AZ91 Mg alloy and Al6063 aluminum alloy sheets during friction stir welding(FsP)was studied.A successful joint was achieved at 1100 *** rotational speed and 25 mm/min tool travel *** of tool rotational speed and tool travel speed has observed a profound effect on the material flow mechanisms at the nugget *** the microstructural studies,the joint formation was observed as mainly due to mechanical mixing of the *** level of metallurgical continuity at the nugget zone was observed as poor and a sharp interface at the joint was *** microhardness measurements across the weld joint also revealed the lack of establishment of a perfect metallurgical bonding.X-ray diffraction analysis of weld zone showed presence of both magnesium and *** from the preliminary observations,it can be understood that the joining of AZ91 Mg alloy and Al6063 alloy can be achieved by FsP;however,complex issues in material mixing still need further investigations.

关键词： Friction stir welding Dissimilar joints Magnesium Aluminum Nugget zone

基于CRITIC-vIKOR方法的创新创业教育评价研究

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辽宁师范大学学报（自然科学版） 2024年第2期47卷 162-167页

作者：王静殷明娥辽宁师范大学管理学院辽宁大连116081 辽宁师范大学数学学院辽宁大连116081

高校创新创业教育是我国创新人才培养的战略要求,相应的教育评价体系是衡量高校创新创业教育发展水平的重要工具.构建科学的质量评价体系不仅是监督反馈机制,对提升创新创业教育实效性也具有重要意义.由于评价指标的权重主要通过专家直... 详细信息

高校创新创业教育是我国创新人才培养的战略要求,相应的教育评价体系是衡量高校创新创业教育发展水平的重要工具.构建科学的质量评价体系不仅是监督反馈机制,对提升创新创业教育实效性也具有重要意义.由于评价指标的权重主要通过专家直接根据主观意识赋值,缺乏客观性.组合赋权法在一定程度上可以弥补这个缺陷. CRITIC-vIKOR法将CRITIC权重法和vIKOR方法相结合,实现优势互补,在很多领域的评价问题中得到应用.使用CRITIC-vIKOR法对辽宁省5所地方院校的创新创业教育质量进行评价和排序,为高校创新创业教育的合理科学评价提供参考.

关键词： CRITIC-vIKOR法熵权TOPsIs法创新创业教育

多元化教育干预对颅内动脉瘤患者术后心理状态和依从性的影响

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中国健康心理学杂志 2024年第5期32卷 736-741页

作者：龚秀娥孟庆南阳医学高等专科学校第一附属医院神经外科 473006 河南省肿瘤医院肿瘤科

目的:探究多元化教育干预对颅内动脉瘤患者术后心理状态和依从性的影响。方法:选取2021年1-12月某院收治的93例颅内动脉瘤患者,随机分为对照组(n=47)和观察组(n=46),对照组给予常规干预,观察组给予多元化教育干预。比较两组心理状态[焦... 详细信息

目的:探究多元化教育干预对颅内动脉瘤患者术后心理状态和依从性的影响。方法:选取2021年1-12月某院收治的93例颅内动脉瘤患者,随机分为对照组(n=47)和观察组(n=46),对照组给予常规干预,观察组给予多元化教育干预。比较两组心理状态[焦虑自评量表(sAs)和抑郁自量表(sDs)]、疾病不确定感[Mishel制定的疾病不确定感量表(MUIs)]、希望水平[中文版Herth希望量表(HHI)]、依从性及生活质量[生活质量综合评定问卷(GQOLI-74)]。结果:干预后相较于对照组,观察组sAs评分和sDs评分明显较低(t=-6.345,-4.613;Ps各维度评分明显较低(t=-7.619,-5.704,-5.191,-3.784;P<0.001),HHI各维度评分明显较高(t=9.718,10.298,3.866;P<0.001),合理膳食、规范用药、规律作息、有氧运动依从性均明显较高(χ^(2)=12.106,7.710,10.831,8.868;P<0.05),GQOLI-74各维度评分明显较高(t=5.811,5.881,7.221,5.809,7.650;P<0.001)。结论:多元化教育干预可明显改善颅内动脉瘤患者术后心理状态,降低疾病不确定感,增强希望水平,提高依从性,提升生活质量。

关键词：多元化教育干预颅内动脉瘤心理状态依从性生活质量

structure,morphology and opto-magnetic properties of Bi_2MoO_6 nano-photocatalyst synthesized by sol-gel method

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Transactions of Nonferrous Metals society of China 2015年第10期25卷 3271-3278页

作者： v.UMAPATHY A.MANIKANDAN s.ARUL ANTONY P.RAMU P.NeeRAJA Research and Development Centre Bharathiar University Caplin Point Laboratories Limited Postgraduate and Research Department of Chemistry Presidency College Department of Chemistry Meenakshi Academy of Higher Education and Research Department of Chemistry Adhiyamaan College of Engineering

Bismuth molybdate （Bi2MoO6） nano-particles （NPs） were synthesized using bismuth nitrate, ammonium molybdate, citric acid and ethyl cellulose by a simple sol-gel method. The structure, morphology, opto-magnetic and photocatalytic properties of the obtained powder were characterized by X-ray diffraction （XRD）, Fourier transform infrared （FT-IR） spectra, high resolution scanning electron microscopy （HRseM）, energy dispersive X-ray （eDX）, ultraviolet-visible diffuse reflectance spectra （DRs）, photoluminescence （PL） spectra and vibrating sample magnetometer （vsM） techniques. The XRD, FT-IR and eDX results indicate that the resultant powder is pure and single phase crystalline Bi2MoO6 with orthorhombic structure. The HRseM image shows that the morphology of obtained powder consists with well defined nano-particles structure. The vsM results show superparamagnetic behavior of the obtained nano-particles. The photocatalytic activity of Bi2MoO6 nano-particles was performed. The addition of TiO2 catalyst enhances the photocatalytic activity of Bi2MoO6 nano-particles. The catalysts Bi2MoO6, TiO2 and mixed oxide catalyst Bi2MoO6-TiO2 nano-composites （NCs） were tested for the photocatalytic degradation （PCD） of 4-chlorophenol （4-CP）. It is found that the PCD efficiency of Bi2MoO6-TiO2 NCs is higher than that of pure Bi2MoO6 and TiO2 catalysts.

关键词： Bi2MoO6 nanostructure sol-gel synthesis optical properties magnetic properties photocatalyst

Natural frequencies of composite beams with a variable fiber volume fraction including rotary inertia and shear deformation

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Applied Mathematics and Mechanics(english edition) 2009年第6期30卷 717-726页

作者： Y. Bedjilili A. Tounsi H. M. Berrabah I. Mechab e. A. Adda Bedia s. Benaissa Université de Tlemcen Faculté des Sciences de l'ingénieurDépartement de Génie MécaniqueAlgérie Laboratoire des Matériaux et Hydrologie Université de Sidi Bel AbbesAlgérie Laboratoire de Mathématiques Université de Sidi Bel AbbesAlgérie

The present study is concerned with the vibration analysis of symmetric composite beams with a variable fiber volume fraction through thickness. First-order shear deformation and rotary inertia have been included in the analysis. The solution procedure is applicable to arbitrary boundary conditions. Continuous gradation of the fiber volume fraction is modeled in the form of an m-th power polynomial of the coordinate axis in the thickness direction of the beam. By varying the fiber volume fraction within the symmetric composite beam to create a functionally graded material （FGM）, certain vibration characteristics are affected. Results are presented to demonstrate the effects of shear deformation, fiber volume fraction, and boundary conditions on the natural frequencies and mode shapes of composite beams.

关键词： free vibration functionally graded materials first-order shear deformationtheory

A new approach for free vibration analysis of a system of elastically interconnected similar rectangular plates

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earthquake engineering and engineering vibration 2022年第4期21卷 947-967页

作者： e.Heidari A.Ariaei Department of Mechanical engineering Faculty of EngineeringUniversity of IsfahanIsfahan ***Iran

A new procedure is proposed to ease the analyses of the free vibration of an elastically connected identical plates system with respect to Kirchhoff plate theory.A structure of n parallel,elastically connected rectangular plates is of concern,whereby the motion is explained by a set of n coupled partial differential *** method involves a new change in variables to uncouple equations and form an equal system of n decoupled plates,while each is assumed to be elastically connected to the *** differential quadrature method is adopted to solve the decoupled *** unravel the original system,the inverse transform is *** the equations enables one to solve them based on the solution methods available for a single plate *** also diminishes the computational costs of such *** considering different boundary conditions,a case study is run to present the method and to validate the results with its counterparts,for which excellent agreement is *** the influence of dimensionless thickness,aspect ratio,and stiffness coefficients on the frequencies reveals the different effects of them at the low order of dimensionless natural frequencies in comparison with high orders and for different boundary conditions.

关键词： multiple-plate system elastic connections free vibration Kirchhoff plate theory differential quadrature method

Fractional gas analysis method for non-metallic inclusion control

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广东有色金属学报 2005年第2期15卷 213-215页

作者： GrigorovichK.v. Krasovskii P.v. shibaevs.s. KrylovA.s. Baikov Institute of Metallurgy and Material science RAS Moscow117911 Russia Depart ment of Computational Mathematics and Cybernetics Moscow State University Moscow119899 Russia

The content, nature, size and distribution of oxide inclusions significantly influence the quality of tyre cord, railway, bearing and stainless steel grades.

关键词：碳钢抗氧化性产品质量非金属内含物分馏气体分析