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Chinese Physics B 2018年第2期27卷 607-612页

作者： sh Khandanjou M Ghoranneviss sh Saviz M Reza Afshar Plasma Physics Research Center Science and Research Branch Islamic Azad University Department of Materials Engineering Science and Research Branch Islamic Azad University

In the present investigation, Ni_（50）Ti_（25）Al_（25）（at.%） mechanically alloyed powder is deposited on carbon steel *** the coating process, the substrate is heated to temperature ranging from room temperature to 400℃. The microstructure, porosity, microhardness, adhesion strength, and corrosion behavior of the coating are investigated at different substrate temperatures. Results show that coating porosity is lower on high temperature surface. Microhardness and adhesion strength of the deposition layer on the substrate without preheating have lower values than with preheating. The polarization test result shows that corrosion performance of the coating is dependent on micro cracks and porosities and the increasing of substrate temperature can improve the quality of coating and corrosion performance.

关键词： Ni50Ti25Al25 coating air plasma spray planetary ball milling inter-metallic compounds corrosion resistance

Solving two-dimensional Volterra-Fredholm integral equations of the second kind by using Bernstein polynomials

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Applied Mathematics(A Journal of Chinese Universities) 2017年第1期32卷 68-78页

作者： M.sh.Dahaghin sh.Eskandari Department of Mathematics Shahrekord University Shahrekord Iran

In this paper, we present a numerical method for solving two-dimensional VolterraFredholm integral equations of the second kind（2DV-FK2）. Our method is based on approximating unknown function with Bernstein polynomials. We obtain an error bound for this method and employ the method on some numerical tests to show the efficiency of the method.

关键词： Volterra approximating approximate variational proof iterative uniformly exact wavelet inequality

Ethnocultural heritage of the North-Eastern Caucasus as a factor of eco-tourism development

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Journal of Mountain Science 2024年第8期21卷 2810-2824页

作者： Zaburaeva Khava sh. Complex Research Institute named after Kh.I.Ibragimov of the Russian Academy of Sciences Grozny 366002Russia

The North-East Caucasus is a multi-ethnic mountain macroregion with a rich cultural heritage,insufficiently studied in the context of the ecotourism *** fill this gap and identify promising directions of environmentally safe forms of tourism,the author used in-depth review of modern literature to investigate the features of ecological tourism and the problems of preserving ethno-cultural heritage,and used historical and comparative-geographical methods to analyze the development of the tangible and intangible cultural heritage of the indigenous peoples of the North-Eastern Caucasus in different historical periods and to identify the geographical peculiarities of the distribution of historical and cultural monuments(tower buildings),pilgrimage sites and centers of traditional crafts and *** part of the planned expeditions,the author personally visited some historical monuments and handicraft centers for a deeper study of ethno-cultural *** cartographic method made it possible to visualize the *** results of the research show that the ethnocultural heritage of the North-East Caucasus is formed by material(historical and cultural monuments)and immaterial elements of culture(language,customs,traditions,ethnic identification)of those peoples,who live *** ethnocultural heritage is considered as the most important factor in the development of the tourism *** is revealed that this region has a large potential for development in various areas of *** highest concentration of religious buildings focused in mountainous *** tower structures were erected in mountainous and high-altitude *** ancient times to the present day there have been preserved various types of crafts and trades(pottery,metalworking,burka making,jewelry making,carpet weaving,gold embroidery,wood and stone carving,etc.),which can become objects of *** ethnocultural heritage of the North-East Caucasus needs to be preserved a

关键词： Mountainous districts Sustainable development Prospects Stone Towers Folk crafts

Gradient maturation experiment on hairs implies taphonomic changes in fossil hairs

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Science China Earth Sciences 2025年第1期 62-73页

作者： Xin LI Yibo ZHOU Tao ZHAO Xingjian HE Yanhong pan State Key Laboratory for Mineral Deposits Research Center for Critical Earth Material Cycling Centre for Research and Education on Biological Evolution and Environment and Frontiers Science School of Earth Sciences and Engineering Nanjing University Institute of Palaeontology Yunnan Key Laboratory of Earth System Science Yunnan Key Laboratory for PalaeobiologyYunnan University

Mammalian hair, as a key feature related to endothermy, physical protection, and camouflage, has a long geohistorical record that dates back even to the Mesozoic. However, the limited information on the taphonomy of hair hinders the understanding of its evolutionary significance in deep time. To address this, we conducted taphonomic experiments to simulate the transformation process of black hair. The changes in the morphological structure, microscopic characteristics, and chemical composition of hair during the simulated fossilization process were documented by scanning electron microscopy, Fourier transform infrared(FTIR) spectroscopy, and Raman spectroscopy. Our results revealed that damage to the morphology of hair began at a mild temperature(150–175°C), and hair transformed into a fluid-like mass at a relatively high temperature(200°C). In addition, the morphological structure of melanosomes had relatively greater preservation potential than keratins did, and the microscopic features of melanosomes were persistently stable. The Raman and FTIR spectra indicated that the characteristic melanin and keratin peaks changed as the temperature increased. Although the chemical signals were not lost completely, the variations in the characteristic amide bands in the FTIR spectra indicate that the keratins severely degraded at high temperatures(>200°C), whereas the characteristic melanin bands in the Raman spectra suggested that melanin signals were still recognizable, even at high temperatures(>200°C). These results were confirmed by principal component analysis(PCA) and principal component analysis linear discriminant analysis(PCA–LDA). In addition, the Raman signals of all the samples in the simulated experiments were distinguished from the signals of common geological carbonaceous materials(humic acid), which suggested that Raman spectroscopy can be used to detect melanin in fossils.

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A module based modeling framework for estimating lunar dust deposition due to human activities

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Chinese Journal of Aeronautics 2024年第2期37卷 501-510页

作者： Chunjian pan College of Automation Engineering Shanghai University of Electric PowerShanghai 200090China

Lunar dust is considered to be one of the top challenges for enabling humans to have extended stays on the *** activities such as module landings and launches,walking,rover operation and construction activities will inevitably produce a significant amount of ***,it is important to estimate the potential range and intensity of dust deposition caused by these activities to minimize dust accumulation over time and for maintenance planning and execution.A modular model that correlates the dust deposition distribution with initial mean dust particle velocity,its mean ejected angle and the total amount of ejected mass is developed for an elementary mechanical *** modular model is further employed to form a modeling framework to estimate dust deposition of a trajectory based activity of similar repeated movements such as the landing process of a lander,walking and rover *** model forms a unified modeling framework for different trajectory-based activities and is shown to predict consistent and physically meaningful ranges and intensities of dust deposition provided reliable data to calibrate the model parameters.

关键词： Lunar dust Dust deposition Lunar lander Lunar construction Model calibration

止血带在导航系统下行全膝关节置换的应用时机选择:一项单中心、回顾性分析

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中国组织工程研究 2025年第15期29卷 3159-3164页

作者：潘浩杨梦刘国强河北省沧州中西医结合医院河北省中西医结合骨关节病研究重点实验室河北省沧州市061000

背景:传统全膝关节置换过程中应用止血带的时机已有明确报道,随着关节相关技术不断精进,导航系统下全膝关节置换应用止血带的时机却鲜有报道。目的:评估采用全程与半程止血带对Brainlab导航系统下行全膝关节置换疗效的影响。方法:回顾... 详细信息

背景:传统全膝关节置换过程中应用止血带的时机已有明确报道,随着关节相关技术不断精进,导航系统下全膝关节置换应用止血带的时机却鲜有报道。目的:评估采用全程与半程止血带对Brainlab导航系统下行全膝关节置换疗效的影响。方法:回顾性分析2022年1-12月在河北省沧州中西医结合医院行导航系统下全膝关节置换患者的资料,选择符合条件的145例患者进行分析,按松开止血带时机分为全程组(n=71)和半程组(n=74)。收集患者一般资料、围术期情况、术后膝关节周围肿胀情况、下肢深静脉血栓发生情况、目测类比评分、美国特种外科医院膝关节评分和关节遗忘评分,评估膝关节功能并进行比较。结果与结论:①与半程组相比,全程组患者的手术时间更短、下肢深静脉血栓发生率更高、术后膝关节肿胀情况更重(P0.05);④提示采用导航系统行全膝关节置换的患者中,半程使用止血带隐匿性失血量少、术后患肢肿胀程度及下肢深静脉血栓发生率低,膝关节功能恢复更快。

关键词：导航系统全膝关节置换止血带膝关节功能关节遗忘评分

不同加载速度下巴厘菠萝果皮穿刺力学特性研究

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农机化研究 2025年第3期47卷 169-175页

作者：薛忠潘睿张秀梅中国热带农业科学院南亚热带作物研究所广东湛江524091 中国热带农业科学院农业机械研究所广东湛江524091 农业农村部热带果树生物学重点实验室广东湛江524091

对菠萝果皮穿刺力学特性进行研究,旨在为果实品质评价提供参考,为菠萝采收、加工设备优化改进提供参考,为减轻菠萝果损伤提供理论依据。以巴厘菠萝果皮为研究对象,根据菠萝生长规律将果皮划分为上、中、下3个部位,基于WSW-50E微机控制... 详细信息

对菠萝果皮穿刺力学特性进行研究,旨在为果实品质评价提供参考,为菠萝采收、加工设备优化改进提供参考,为减轻菠萝果损伤提供理论依据。以巴厘菠萝果皮为研究对象,根据菠萝生长规律将果皮划分为上、中、下3个部位,基于WSW-50E微机控制电子万能试验机,选取2、5、10、20、50 mm/min等5个加载速度对菠萝不同部位进行穿刺力学特性试验,分析不同加载速度、不同穿刺部位和不同穿刺压头截面对果皮穿刺强度的影响。试验结果表明:果皮中部穿刺强度最低,下部穿刺强度最高;压头截面与不同穿刺部位对果皮穿刺强度均呈现负相关极显著(p<0.01),不同穿刺部位对果皮穿刺强度均呈现正相关极显著(p<0.01),压头截面与穿刺部位对穿刺强度影响极显著(p<0.01)。由此得出结论:果皮穿刺强度与压头截面、穿刺部位呈极显著相关关系,加载速度与穿刺强度呈不相关关系。

关键词：菠萝果皮加载速度压头截面穿刺强度

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额尔齐斯河流域不同土地利用区大型真菌资源分布调查

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新疆师范大学学报（自然科学版） 2025年第1期44卷 42-50页

作者：潘冉冉新疆师范大学生命科学学院、中亚区域跨境有害生物联合控制国际研究中心、新疆特殊环境物种保护与调控生物学实验室新疆乌鲁木齐830017

为探明额尔齐斯河流域大型真菌资源及分布,本研究采用访谈法、样方法以及样线法,分别于2022年6月至8月和2023年7月至8月对额尔齐斯河流域及周边主要耕地、自然草场、林区和食用菌种植区的大型真菌资源进行调查和监测。本研究在692个踏... 详细信息

为探明额尔齐斯河流域大型真菌资源及分布,本研究采用访谈法、样方法以及样线法,分别于2022年6月至8月和2023年7月至8月对额尔齐斯河流域及周边主要耕地、自然草场、林区和食用菌种植区的大型真菌资源进行调查和监测。本研究在692个踏查点中共采集大型真菌样本136份,经鉴定该区域有大型真菌2门2纲6目14科24属31种。其中鬼伞属(Coprinus)最丰富,有4种,占总物种数的12.90%;斑褶菇属(panaeolus)次之,有3种,占总物种数的9.68%;侧耳属(Pleurotus)和丝膜菌属(Cortinarius)分别有2种,各占总物种数的6.45%;其余20属均仅有1种。调查发现,额尔齐斯河流域大型真菌资源在沿河流域的林地和草地分布较密集,在人为干扰环境,如建筑用地分布较少。此外,通过对大型真菌子实体生境因子监测发现,大型真菌子实体的分布与温度、湿度等环境因子相关,其中皱环球盖菇(Stropharia rugosoannulata)对环境的抗逆性强,可作为潜在食用栽培菌。本研究可为该地区大型真菌物种多样性、食用菌业育种开发等提供本底资源数据。

关键词：大型真菌资源生态功能空间分布环境因子

Two-dimensional analysis of a negative differential conductance gate transistor as a THz emitter

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Plasma Science and Technology 2017年第4期19卷 15-22页

作者： sh RAHMATALLAHPUR A ROSTAMI S KHORRAM Photonics and Nanocrystal Research Lab.(PNRL) Faculty of Electrical and Computer EngineeringUniversity of TabrizTabriz 51666-14761Iran Photonics Group Research Institute for Applied Physics and Astronomy(RIAPA)University of TabrizTabriz 51664-14761Iran

We investigate plasma modes in a transistor including a negative differential conductance in the gate. The analytical results show that the plasma wave generation is substantially influenced by the lateral direction （width of the transistor）, gate leakage current and ＇viscosity. The injection from the gate （opposed to the gate leakage current） can improve the plasma oscillations and their amplitude with respect to ordinary transistors. We also estimate, which to our best knowledge has been derived for the first time, the total power emitted by the transistor and the emitted pattern which qualitatively gives reasonable agreement with the experimental data. The results show that the radiated power depends on various parameters such as drift velocity, momentum relaxation time, gate leakage current and especially the lateral direction. A negative gate current enhances the power while the gate leakage current decreases the power.

关键词： terahertz emitter solid state plasma two-dimensional analysis negative differentialconductance

IMPORTANCE OF MOIST AMBIENT AND ITS HELICAL ENHANCEMENT EFFECT TO STORM INTENSITY

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Journal of Hydrodynamics 2004年第6期16卷 743-755页

作者： Al-FALAHI Fadha sh. Key Laboratory of Mesoscale Severe Weather Ministry of Education Department of Atmospheric Sciences Nanjing University Nanjing 210093 China

A crucial issue in evolution of severe storm, such as typhoon and even singlesupercell, is to diagnose and predict the sudden intensifying in storm. This paper describes anattempt to investigate the influence and effect of ambient moisture in the development of storm. Itwas mainly through a dynamic way to detect the helical enhancement by ambient moisture. It was foundthat the correlation between the ambient moistness and the intensity of rotating convective cellscan be well analyzed by helicity dynamics. The correlation between environmental streamwisevorticity (i. e. helicity) and vertical velocity (storm updraft or downdraft) is a powerfulindicator to catch favorable or unfavorable conditions for storm evolution. For this purpose, athree-dimensional non-hydrostatic storm-scale model, Advanced Regional Prediction System CARPS) wasemployed in order to numerically simulate a well-documented case of Del City supercell storm indifferent kinds of environmental moistness. Moreover, such different kinds of ambient moistenvironment and the resultant different morphologies and evolutions in the storm clearlydemonstrated that the abundant moistness in the environment that the storm embedded significantlystrengthens tbe storm intensity. In fact, the storm is embedded in much moist environment andtherefore larger instability propagates faster than the one in the drier air. It further producesstronger low-level mesocyclone with a much longer lifetime. The stronger convection and twist in theupdraft indicates that helical enhancement effect by moisture lead to stronger tornadic activity insevere storm.

关键词： moist ambient intensity of storm helical enhancement