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Methanolic pomegranate dried peel extract improves cryopreserved semen quality and antioxidant capacity of rams

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亚太生殖杂志:英文版 2023年第5期12卷 229-238页

作者： Amal M.Aboelmaaty Mohamed S.Kotp Aya M.Fadl Elshymaa A.Abdelnaby Islam E.El-Seadawy Hossam R.El-Sherbiny Animal Reproduction and Artificial Insemination Department Veterinary Research InstituteNational Research CentreCairoEgypt Theriogenology Department Faculty of Veterinary MedicineCairo UniversityCairoEgypt

Objective:To select the appropriate concentrations of methanolic pomegranate extract supplemented in rams’semen extender for obtaining the best-cryopreserved semen quality.Methods:Tris-based semen extender was supplemented with 0.0,0.40,0.48,and 0.56 mg/mL pomegranate peel methanolic extract to extend semen collected from five native rams twice weekly for two months(n=80).Pooled(n=16)post-thaw semen characteristics were determined.Thawed seminal plasma of all supplemented and control groups were used to measure malondialdehyde(MDA),nitric oxide(NO),glutathione peroxidase(GPx),superoxide dismutase(SOD),ascorbic acid,zinc,copper,total cholesterol,low-density lipoproteins(LDL),lactate dehydrogenase(LDH),and alkaline phosphatase(ALP).Results:The supplementation of Tris-based semen extender with 0.48 mg/mL semen extender resulted in the highest post-thaw sperm total motility(P0.05),and LDH(P>0.05).Conclusions:Pomegranate peel methanolic extract 0.48 mg/mL supplemented to Tris-based semen extender of rams is the best enrichment in preserving the sperm post-thaw characteristics via improving biochemical profiles and antioxidant capacity.

关键词： Oxidants-antioxidants Pomegranate peel ethanolic extract Post-thaw semen characteristics Tris-based semen diluents rams

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基于rams的数控机床综合评价方法研究

机械工程学报 2022年第9期58卷 218-230页

作者：黄祖广王舒辉王金江张凤丽通用技术集团机床工程研究院有限公司北京100102 中国石油大学(北京)安全与海洋工程学院北京102249

数控机床作为航空航天、海洋船舶和轨道交通等现代工业的制造母机,其结构庞杂,功能系统强耦合,运行工况多变,尤其是近年来其在高速、高精和智能化方向的迅猛发展,使得其安全可靠性已成为制约行业发展的关键共性问题。而传统的数控机床... 详细信息

数控机床作为航空航天、海洋船舶和轨道交通等现代工业的制造母机,其结构庞杂,功能系统强耦合,运行工况多变,尤其是近年来其在高速、高精和智能化方向的迅猛发展,使得其安全可靠性已成为制约行业发展的关键共性问题。而传统的数控机床评价方法多从可靠性或维修性等单维度进行分析,导致评价结果的片面化和局限性,难以满足全方位分析评价的要求。基于可靠性、可用性、维修性和安全性(Reliability,availability,maintainability,safety,rams)理念,从可靠性、维修性、安全性和可用性等多维度入手分析,提出了数控机床多维度评价指标,结合故障总时间法、韦布尔比例失效率模型、灰色聚类法、模糊理论和层次分析法等方法理论,建立了数控机床rams综合评价方法。以数控机床电主轴功能部件为例,验证了rams综合评价方法的有效性。

关键词：数控机床 rams 故障总时间法比例失效率模型模糊理论灰色聚类层次分析

A Review Featuring Fabrication, Properties and Applications of Carbon Nanotubes(CNTs) Reinforced Polymer and Epoxy Nanocomposites

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Chinese Journal of Polymer Science 2018年第4期36卷 445-461页

作者： Sobia Imtiaz Muhammad Siddiq Ayesha Kausar Sedra Tul Muntha Jaweria Ambreen Iram Bibi Department of Chemistry Quaid-i-Azam University Department of Physics Comsats Institute of Information Technology Department of Chemistry Hazara University

Carbon nanotubes（CNTs） have long been recognized as the stiffest and strongest man-made material known to date. In addition, their high electrical conductivity has roused interest in the areas of electrical appliances and communication related applications. However, due to their miniature size, the excellent properties of these nanostructures can only be exploited if they are homogeneously embedded into light-weight matrices as those offered by a whole series of engineering polymers. In order to enhance their chemical affinity to engineering polymer matrices, chemical modification of the graphitic sidewalls and tips is necessary. The mechanical and electrical properties to date of a whole range of nanocomposites of various carbon nanotube contents are also reviewed in this attempt to facilitate progress in this emerging area. Recently, carbonaceous nano-fillers such as graphene and carbon nanotubes（CNTs） play a promising role due to their better structural and functional properties and broad range of applications in every field. Since CNTs usually form stabilized bundles due to van der Waals interactions, they are extremely difficult to disperse and align in a polymer matrix. The biggest issues in the preparation of CNTs reinforced composites reside in efficient dispersion of CNTs into a polymer matrix, the assessment of the dispersion, and the alignment and control of the CNTs in the matrix. An overview of various CNT functionalization methods is given. In particular, CNT functionalization using click chemistry and the preparation of CNT composites employing hyperbranched polymers are stressed as potential techniques to achieve good CNT dispersion. In addition, discussions on mechanical, thermal, electrical, electrochemical and applications of polymer/CNT composites are also included.

关键词： Polymer nanocomposites CNTs Epoxy Conducting polymers rams

Resonant Absorption Mechanical Spectrometer and Its Applications in Solids

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Chinese Physics Letters 2003年第10期20卷 1807-1810页

作者：张进修龚康熊小敏丁喜冬 StateKeyLaboratoryofOptoelectronicsofMaterialsandTechnologiesandDepartmentofPhysics ZhongshanUniversityGuangzhou510275

An improved apparatus is developed from Ke-pendulum. This new apparatus, resonant absorption mechanical spectrometer (rams), can measure the internal friction of solids under a forced vibration mode and the measuring frequency can change quasi-continually from a frequency that is much lower than the resonant frequency of the pendulum system, fr, to the one that is much higher than fr. The internal friction measurement is able to cover the frequency range from 10-3Hz to kHz. The measurement method and the calculation formula of the internal friction measured by a rams in the full frequency range are derived. A series of resonant absorption peaks are observed in copper, aluminium, zinc, iron samples by the rams. The resonant absorption characteristics of the copper sample are studied in details. The experimental results indicate that the position (frequency) of the resonant absorption peaks are independent of the resonant frequency of the pendulum system. The reality of resonant absorption mechanical spectra is discussed and an inference based on the experimental results is presented such that the rams is able to characterize some feature of solid materials.

关键词：共振吸收机械分光计应用固体物理 rams 位错环共振吸收力学谱

Numerical Simulation of Fluxes Generated by Inhomogeneities of the Underlying Surface over the Jinta Oasis in Northwestern China

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Advances in Atmospheric Sciences 2011年第4期28卷 887-906页

作者：李万莉吕世华傅慎明孟宪红 H.C.NNAMCHI Key Laboratory of Land Surface Process and Climate Change in Cold and Arid Regions Cold and Arid Regions Environmental and Engineering Research InstituteChinese Academy of Sciences Institute of Atmospheric Physics Chinese Academy of Sciences Department of Geography University of Nigeria

Using land-use types derived from satellite remote sensing data collected by the EOS Moderate Resolution Imaging Spectroradiometer （EOS/MODIS）, the mesoscale and turbulent fluxes generated by inhomogeneities of the underlying surface over the Jinta Oasis, northwestern China, were simulated using the Regional Atmospheric Modeling System （rams4.4）. The results indicate that mesoscale circulation generated by land-surface inhomogeneities over the Jinta Oasis is more important than turbulence. Vertical heat fluxes and water vapor are transported to higher levels by mesoscale circulation. Mesoscale circulation also produces mesoscale synoptic systems and prevents water vapor over the oasis from running off. Mesoscale circulation transports moisture to higher atmospheric levels as the land-surface moisture over the oasis increases, favoring the formation of clouds, which sometimes leads to rainfall. Large-scale wind speed has a significant impact on mesoscale heat fluxes. During the active phase of mesoscale circulation, the stronger large-scale winds are associated with small mesoscale fluxes; however, background wind seems to intensify the turbulent sensible heat flux and turbulent latent heat flux. If the area of oasis is enlarged properly, mesoscale circulation will be able to transport moisture to higher levels, favoring the formation of rainfall in the oasis and protecting its ＂cold island＂ effect. The impact of irrigation on rainfall is important, and increasing irrigation across the oasis is necessary to protect the oasis.

关键词： inhomogeneities rams mesoscale circulation turbulence heat flux

基于rams的轨道交通转向架关键部件状态评估

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兵器装备工程学报 2022年第9期43卷 83-89页

作者：刘俊洁徐永能马文军张斌峰南京理工大学自动化学院南京210094

将转向架系统的关键部件利用ABC分类法筛选,应用rams对轨道交通转向架关键部件进行状态评估,利用安全性确定部件维修方式,利用可靠性确定部件维修时间间隔,利用可用性判断部件维修状态。以某地铁公司的转向架系统数据为例,以故障分布函... 详细信息

将转向架系统的关键部件利用ABC分类法筛选,应用rams对轨道交通转向架关键部件进行状态评估,利用安全性确定部件维修方式,利用可靠性确定部件维修时间间隔,利用可用性判断部件维修状态。以某地铁公司的转向架系统数据为例,以故障分布函数及风险优先数方法制定关键部件维修措施,以运营可用度决定是否采用该维修措施,确定了车轮和一系弹簧需采用更新后的维修措施。此状态评估方法对部件维修措施制定与实施具有指导性作用。

关键词：轨道交通转向架 rams 关键部件故障分布函数风险优先数状态评估

Influence of Topography and Large-scale Forcing on the Occurrence of Katabatic Flow Jumps in Antarctica:Idealized Simulations

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Advances in Atmospheric Sciences 2007年第5期24卷 819-832页

作者：余晔 Xiaoming CAI 郄秀书 School of Geography Earth and Environmental Sciences University of Birmingham Edgbaston Birmingham B15 2TT United Kingdom Department of Plateau Atmospheric Physics Cold and Arid Regions Environment and Engineering Research Institute Chinese Academy of Sciences Lanzhou 730000 Laboratory for Middle Atmosphere and Global Environment Observation （ LA GEO） Institute of Atmospheric Physics Chinese Academy of Sciences Beijing 100029

The Regional Atmospheric Modeling System （rams）, which is a non-hydrostatic numerical model, has been used to investigate the impact of terrain shape and large-scale forcing on the Antarctic surface-wind regime, focusing on their roles in establishing favorable flow conditions for the formation of katabatic flow jumps. A series of quasi-2D numerical simulations were conducted over idealized slopes representing the slopes of Antarctica during austral winter conditions. Results indicate that the steepness and variations of the underlying slope play a role in the evolution of near-surface flows and thus the formation of katabatic flow jumps. However, large-scale forcing has a more noticeable effect on the occurrence of this small-scale phenomenon by establishing essential upstream and downstream flow conditions, including the upstream supercritical flow, the less stably stratified or unstable layer above the cold katabatic layer, as well as the cold-air pool located near the foot of the slope through an interaction with the underlying topography. Thus, the areas with steep and abrupt change in slopes, e.g. near the coastal areas of the eastern Antarctic, are preferred locations for the occurrence of katabatic flow jumps, especially under supporting synoptic conditions.

关键词： Antarctic katabatic jump numerical simulation rams

Charge Structure of a Summer Thunderstorm in North China:Simulation Using a Regional Atmospheric Model System

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Advances in Atmospheric Sciences 2014年第5期31卷 1022-1034页

作者： LIU Dongxia QIE Xiushu PENG Liang LI Wanli Key Laboratory of Middle Atmosphere and Global Environment Observation Institute of Atmospheric PhysicsChinese Academy of Sciences Collaborative Innovation Center on Forecast and Evaluation of Meteorological Disasters Nanjing University of Information Science & Technology National Center of Atmospheric Research China Meteorological Administration Training Center

Electrification and simple discharge schemes are coupled into a 3D Regional Atmospheric Model System （rams） as microphysical parameterizations, in accordance with electrical experiment results. The dynamics, microphysics, and electrifi- cation components are fully integrated into the rams model, and the inductive and non-inductive electrification mechanisms are considered in the charging process. The results indicate that the thunderstorm mainly had a normal tripole charge structure. The simulated charge structure and lightning frequency are basically consistent with observations of the lightning radiation source distribution. The non-inductive charging mechanism contributed to the electrification during the whole lifetime of the thunderstorm, while the inductive electrification mechanism played a significant role in the development period and the mature stage when the electric field reached a large value. The charge structure in the convective region and the rearward region are analyzed, showing that the charge density in the convective region was double that in the rearward region.

关键词： rams electrification parameterization discharge parameterization charge structure thunderstorm

Testicular vasomotion in different mammals

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Asian Journal of Andrology 2000年第4期2卷 297-300页

作者： Ola Collin JimL.Zupp BrianP.Setchell Department of Integrative Medical Biology Section for Anatomy Umed University SwedenDepartment of Animal Science University of Adelaide AustraliaDepartment of Animal Science University of Adelaide Australia

Vasomotion is a rhythmical variation in arterial blood flow present in many different organs among them the mttestis. Vasomofion is suggested to play an important role for the transvascular fluid exchange and the exchange of nutri-ents over the capillary wall as well as the formation of interstitial fluid. The present study was undertaken to elucidatewhether vasomotion is present in the testes of different species independent of their anatomical vascular topography.Blood flow in the testes of mouse, brush-tailed possum, tammar wallaby, ram and human was investigated by using alaser Doppler fiowmeter. Vasomotion was found in all the species investigated. (Asian J Androl 2000 Dec; 2: 297-30O)

关键词： testis vasomotion human rats possum rams mice tammar-wallaby