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Optical, Structural and Morphological Properties of Photocatalytic ZnO Thin Films Deposited by Pray Pyrolysis Technique

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Modern research in Catalysis 2016年第4期5卷 130-146页

作者： Durgam Komaraiah Eppa radha Y. vijayakumar J. Sivakumar M. v. ramana reddy r. Sayanna Department of Physics University College of Science Osmania University Hyderabad India

Photocatalytic ZnO thin films have been deposited onto glass substrate by spray pyrolysis technique. The sprayed solution consists of 0.1 M of zinc acetate dihydrate dissolved in double distilled water and sprays onto ultrasonically cleaned glass substrates maintained at 350°C, through an air-atomizing nozzle. The X-ray diffraction (XrD), scanning electron microscopy (SEM), EDX and Uv-vIS spectrophotometer were applied to describe the structural, morphological, compositional and optical properties of ZnO catalyst. XrD analysis confirms that the films were found to be single phase hexagonal wurtzite structure. The SEM micrograph of the films is shown highly uniform, crack free and found to be fiber like structures. The optical transmittance spectra of the ZnO thin films were found to be transparent to visible light and the average optical transmittance was greater than 85%. The direct optical band gap energy values of the films shift towards the lower energy as a consequence of the thermal annealing. The Urbach energy of the films was found to increase with annealing temperature. The refractive index of the films was calculated and the refractive index dispersion curve of the films obeys the single oscillator model. The values of oscillatory energy Eo, dispersion energy Ed, and static dielectric constant εs for the ZnO thin films were determined. The films were evaluated for their ability to degrade methylene blue. The Langmuir-Hinshelwood kinetic model was used to interpret quantitatively the observed kinetic experimental result. The photocatalytic activity of ZnO thin films was enhanced by annealing temperature.

关键词： ZnO Thin Film Spray Pyrolysis Optical Band Gap refractive Index Photo Catalysis

Igor v. venin Founder of Biphasic Waveform Defibrillators

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Journal of Biomedical Science and Engineering 2015年第5期8卷 345-349页

作者： vyacheslav A. vostrikov Boris B. Gorbunov Sergey v. Selishchev Laboratory of Clinical Pathophysiology of Critical States Negovsky Research Institute of General Reanimatology Moscow Russia Laboratory of Electrophysiological Methods in Cardiology Department of Cardiology of Research Centre Sechenov First Moscow State Medical University Moscow Russia Department of Biomedical Systems National Research University of Electronic Technology Zelenograd Moscow Russia

Igor v. venin since 1966 and up till now has been an outstanding engineer of the Soviet Union and Ukraine, who has dedicated all his life to defibrillators development. Under his guidance 16 models of DC defibrillators with different waveforms, including the world’s first defibrillator with biphasic waveform (1971) have been developed and put into commercial production.

关键词： History of Defibrillation World’s First Biphasic Defibrillator Gurvich-venin Biphasic Defibrillation Pulse

高效薄层色谱法快速测定由药用植物内生真菌产生的紫杉醇(英文)

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色谱 2008年第1期26卷 50-55页

作者： GANGADEvI v MUTHumarY J Centre for Advanced Studies in Botany University of MadrasGuindy Campus

Taxol is an important anticancer drug used widely in the clinical *** this study,some endophytic fungi were isolated from selected medicinal plants,and were screened for their potential in the production of taxol,using a rapid separation technique of high performance thin layer chromatography(HPTLC).Of the 20 screened fungi,only 13 fungal species produced taxol in the artificial culture *** results of HPTLC showed that the 13 fungal species had identical ultraviolet(Uv) characteristics,positive reactivity with a spray reagent,yielding a blue spot,which turned to dark gray after 24 hours,and had rf values identical to that of the authentic *** amount of taxol was also quantified by comparing the peak area and the peak height of the fungal samples with those of authentic taxol.

关键词：真菌内生植物药用植物高效薄层色谱紫杉醇含量测定

In silico analysis of rNA and small rNA sequencing data from human BM-MSCs and differentiated osteocytes, chondrocytes and tenocytes

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Engineered regeneration 2021年第1期2卷 19-30页

作者： Srinivas v.Koduru Irina A.Elcheva Ashley N.Leberfinger Dino J.ravnic Irvin S.Zubar Plastic Surgery research Laboratory Penn State College of Medicine500 University DriveHersheyPA 17033-0850United States Department of Surgery Penn State Health Milton S.Hershey Medical CenterHersheyPAUnited States Department of Cellular and Molecular Physiology Penn State College of MedicineHersheyPAUnited States Division of Pediatric Hematology/Oncology Department of PediatricsPenn State College of MedicineHersheyPAUnited States

Background:Adult stem cells have a remarkable capacity of differentiating into various cell types necessary for tissue and organ *** studies have focused on the differentiation potential of mesenchymal stem cells(MSCs),however little is known about the molecular characteristics of MSCs and their progenies obtained from donors of different *** this study,we analyzed publicly available sequencing data obtained from young(~22-year-old,n=8)and older(~65.5-year-old,n=8)donors of MSCs and their differentiated counterparts:osteocytes,chondrocytes and *** raw mrNA and small rNA(non-coding rNA)sequencing data was downloaded from NIH BioProjects and systematically analyzed in order to identify uniquely expressed genes in MSC-derived osteocytes,chondrocytes and tenocytes of younger and older ***:We identified many commonly up-and downregulated genes are similar in both ***,the young group displayed a greater variety of differentially expressed genes in all analyzed MSC-derived *** discrepancy in gene expression profiles between younger and older groups may indicate a greater differentiation potential of MSCs isolated from younger *** and mrNA integrated analysis showed key mirNAs that regulate mrNAs in both groups from all differentiated ***:Our analysis provides additional information to previously reported data for identification of MSC markers of plasticity and *** addition,our data may shed light upon the molecular mechanisms of age-associated musculoskeletal diseases caused by a decreased capacity of MSCs to regenerate the locomotor system in elderly people.

关键词： BM-MSCs Osteocytes Chondrocytes Tenocytes Small rNA mirNA-mrNA

内生商业周期的宏观模型——马克思经济学的分析

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经济资料译丛 2003年第1期 1-10页

作者： r.v.伊格林任力厦门大学经济学系 361005

(一)马克思对"资本主义运动规律"的关注致使他把把商业周期和劳动剥削作为资本主义制度的特征.资本主义被视为高度动态化的经济机器,在资本积累、技术变革和失业后备军的不停的和对抗的压力下保持运动.本文提出一个马克思的宏观经济的模... 详细信息

(一)马克思对"资本主义运动规律"的关注致使他把把商业周期和劳动剥削作为资本主义制度的特征.资本主义被视为高度动态化的经济机器,在资本积累、技术变革和失业后备军的不停的和对抗的压力下保持运动.本文提出一个马克思的宏观经济的模型,该模型使对这个体系的静态均衡情况和动态周期模式的特性的分析有了可能.在静态的分析中,该模型给出了确定失业水平,剥削率和利润率的均衡解.当将其动态化时,本模型为分析马克思商业周期的决定提供了基础.它论证了一个自生的内生周期,在这个内生周期中,失业率在连续周期里从低谷到低谷地上升.因此,本模型用公式表述马克思和分析,在一定程度上使对该系统的作用的简明概述成为可能.而且根据商品市场总是出清的古典假设,内生周期被证明是存在的,本模型揭示了马克思的劳动市场理论以及技术变革概念怎样改造古典经济理论,这对论证资本主义经济内在的不稳定是必要的.

关键词：商业周期马克思内生周期经济学分析宏观经济数学模型资本

Incubation of PbSe Thin Films in a Tin(Ⅱ) Salt Aqueous Solution:Modification and Ion-Exchange reactions

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Journal of Materials Science & Technology 2015年第8期31卷 790-797页

作者： Zinaida I.Smirnova Larisa N.Maskaeva vyacheslav F.Markov vladimir I.voronin Mikhail v.Kuznetsov Ural Federal University(named after the First President of russia B.N.Yeltsin) ul.Mira 19Yekaterinburg620002Russia Ural Institute of State Fire Service of EMErCOM of russia Yekaterinburgul.Mira 22620062Russia Institute of Metal Physics Ural BranchRussian Academy of Sciencesul.S.Kovalevskoy 18Yekaterinburg620041Russia Institute of Solid State Chemistry Ural BranchRussian Academy of Sciencesul.Pervomaiskaya 91Yekaterinburg620990Russia

Topochemical ion-exchange reactions between solid micro- and nanostructured metal chalcogenides and aqueous salt solutions are generally used for formation of composite structures based on initial metal chalcogenides and products of their ion-exchange transformation. However, ion exchange has promises as a route to obtaining both composites and solid solutions based on the initial and the end chalcogenide phases. With the help of the ion-exchange technique, single-phase films of Phi xSnxSe substitutional solid solutions with a tin content up to -2 at.%, which are promising for mid- and long-wavelength infrared radiation （Ir） optoelectronics, have been obtained at the interface between PbSe poly- crystalline thin films and SnCl2 aqueous solutions containing sodium citrate. It has been shown that the pH value and temperature of the reaction system play an important role in the ion-exchange process. Incubation of lead selenide （PbSe） films in a tin（II） salt aqueous solution also leads to their modification with oxygen-containing tin compounds to a depth of-3 nm. Differences in the film structure, such as changes in the coherent scattering region sizes and orientation of crystallites along the [220] direction, which arise during the contact with citrate-containing SnCl2 solutions, have also been revealed. For the first time, an idea of the existence of a relatively wide reaction zone of an intragranular topochemical ion-exchange reaction in an aqueous solution, within which substitutional solid solutions can form in micro- and nanostructured systems, has been set forth.

关键词： Ion-exchange synthesis Thin films Lead selenide Tin selenide Substitutional solid solutions Topochemical reaction

Anomalous in-plane magnetoresistance of electron-doped cuprate La_(2.x)Ce_xCuO_(4±δ)

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Science China(Physics,Mechanics & Astronomy) 2017年第9期60卷 70-75页

作者： Heshan Yu Ge He Yanli Jia Xu Zhang Jie Yuan Beiyi Zhu A.Kusmartseva F.v.Kusmartsev Kui Jin Beijing National Laboratory for Condensed Matter Physics Institute of Physics Chinese Academy of Sciences University of Chinese Academy of Sciences CAS Key Laboratory of vacuum Physics University of Chinese Academy of Sciences Department of Physics Loughborough University Collaborative Innovation Center of Quantum Matter

We report systematic in-plane magnetoresistance measurements on the electron-doped cuprate La_(2.x)Ce_xCuO_(4±δ) thin films as a function of Ce doping and oxygen content in the magnetic field up to 14 T. A crossover from negative to positive magnetoresistance occurs between the doping level x = 0.07 and 0.08. Above x = 0.08, the positive magnetoresistance effect appears, and is almost indiscernible at x = 0.15. By tuning the oxygen content, the as-grown samples show negative magnetoresistance effect, whereas the optimally annealed ones display positive magnetoresistance effect at the doping level x = 0.15. Intriguingly, a linear-field dependence of in-plane magnetoresistance is observed at the underdoping level x = 0.06, the optimal doping level x = 0.1 and slightly overdoping level x = 0.11. These anomalies of in-plane magnetoresistance may be related to the intrinsic inhomogeneity in the cuprates, which is discussed in the framework of network model.

关键词：铜氧化物电子掺杂磁异常平面磁电阻效应最佳掺杂浓度电子系统 Ce掺杂

randomization of Energy and Momentum in Statistical Mechanics

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Journal of Modern Physics 2015年第15期6卷 2198-2201页

作者： v. v. Paranjape Department of Physics Lakehead University Thunder Bay Canada

Particle-particle collisions in materials give rise to a particle distribution in energy and momentum in such a way that a most probable distribution is realized. I will show that an evaporating liquid generates a molecular imbalance in the equilibrium energy distribution. The molecular collisions by their inherent nature are able to repair the imbalance and in so doing it is shown that the liquids cool down. Similarly an external electric field creates substantial imbalance in the momentum distribution for the electrons in ionic semiconductors. Electron-electron collisions are able to restore the imbalance and as a consequence, similar to the evaporating liquid, the electron gas loses thermal energy and cools down.

关键词： Particle Distribution Cooling Liquids Electrical Field Imbalance

喷雾热解法在硅衬底上生长定向碳纳米管阵列(英文)

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新型炭材料 2013年第4期28卷 284-288页

作者： v S Angulakshmi K rajasekar C Sathiskumar S Karthikeyan Department of Chemistry Kathir college of EngineeringCoimbatoreTNIndia Department of Nanotechnology Anna University of TechnologyCoimbatoreTNIndia Department of Chemistry Chikkanna Govt.Arts CollegeTirupurTNIndia

以向日葵油的甲基酯为碳源,二茂铁为催化剂前驱体,Ar为载气,通过喷雾热解法在硅衬底上合成定向碳纳米管阵列。结果表明,在硅衬底上原位形成Fe催化剂纳米颗粒。由拉曼光谱、透射电镜图和X-射线衍射谱图显示所制定向碳纳米管阵列具有较好... 详细信息

以向日葵油的甲基酯为碳源,二茂铁为催化剂前驱体,Ar为载气,通过喷雾热解法在硅衬底上合成定向碳纳米管阵列。结果表明,在硅衬底上原位形成Fe催化剂纳米颗粒。由拉曼光谱、透射电镜图和X-射线衍射谱图显示所制定向碳纳米管阵列具有较好的石墨化程度,其直径为1 0～3 0 nm,管壁约为1 0 nm。所制定向碳纳米管阵列中残留的催化剂含量可以忽略。

关键词：喷雾热解法定向碳纳米官阵列二茂铁硅衬底化学气相沉积