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Chinese Physics B 2012年第7期21卷 551-558页

作者： Jijoy.P.Mathew George varghese Jacob Mathew Thin Film Research Laboratory Department of PhysicsSt.Berchmans CollegeChanganasseryKerala 686101India Department of Physics Calicut UniversityThenjippalamKeralaIndia

ZnO thin films were synthesised by a new method which uses polyvinyl alcohol （PVA） as the polymer precursor. The films are annealed at different temperatures and for different annealing times. The structural parameters, like grain size, lattice constants, optical band gap, and Urbach energy, depend on the annealing temperature and time. All the films possess tensile strain, which relaxes as the annealing temperature and time increase. The photoluminescence （PL） spectra contain only ultraviolet （UV） peaks at low temperature, but as the annealing temperature and time increase, we observe peaks at the blue and green regions with a variation in the intensities of these peaks with annealing temperature and time.

关键词： stress, band gap, Urbach energy photoluminescence

Growth Kinetics of Nanocrystals and Nanorods by Employing Small-angle X-ray Scattering (SAXS) and Other Techniques

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Journal of Materials Science & Technology 2008年第4期24卷 615-627页

作者： Kanishka BISWAS Neenu varghese C.N.R.Rao Chemistry and Physics of Materials Unit DST Nanoscience Unit and CSIR Centre of Excellence in ChemistryJawaharlal Nehru Centre for Advanced Scientific ResearchJakkur P.O.Bangalore 560064India Solid State and Structural Chemistry UnitIndian Institute of ScienceBangalore 560012India Chemistry and Physics of Materials Unit DST Nanoscience Unit and CSIR Centre of Excellence in ChemistryJawaharlal Nehru Centre for Advanced Scientific ResearchJakkur P.O.Bangalore 560064India

In this article, we report the results of our detailed investigations of the growth kinetics of zero-dimensional nanocrystals as well as one-dimensional nanorods by the combined use of small angel X-ray scattering （SAXS）, transmission electron microscopy （TEM） along with other physical techniques. The study includes growth kinetics of gold nanocrystals formed by the reduction of HAuCl4 by tetrakis（hydroxymethyl） phosphonium chloride in aqueous solution, of CdSe nanocrystals formed by the reaction of cadmium stearate and selenium under solvothermal conditions, and of ZnO nanorods formed by the reaction of zinc acetate with sodium hydroxide under solvothermal conditions in the absence and presence of capping agents. The growth of gold nanocrystals does not follow the diffusion-limited Ostwald ripening, and instead follows a Sigmoidal rate curve. The heat change associated with the growth determined by isothermal titration calorimetry is about 10 kcal·mol^-1 per I nm increase in the diameter of the nanocrystals. In the case of CdSe nanocrystals also, the growth mechanism deviates from diffusion-limited growth and follows a combined model containing both diffusion and surface reaction terms. Our study of the growth kinetics of uncapped and poly（vinyl pyrollidone）（PVP）-capped ZnO nanorods has yielded interesting insights. We observe small nanocrystals next to the ZnO nanorods after a lapse of time in addition to periodic focusing and defocusing of the width of the length distribution. These observations lend support to the diffusion-limited growth model for the growth of uncapped ZnO nanorods. Accordingly, the time dependence on the length of uncapped nanorods follows the L3 law as required for diffusion-limited Ostwald ripening. The PVP-capped nanorods, however, show a time dependence, which is best described by a combination of diffusion （L^3） and surface reaction （L^2） terms.

关键词： Growth kinetics Gold nanocrystals CdSe nanocrystals ZnO nanorods Small angle X-ray scattering Transmission electron microscopy Ostwald ripening and sigmoidal growth

Modeling of large scale solar cell handling robot with belt-driven flexible arms

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Theoretical & Applied Mechanics Letters 2013年第1期3卷 77-80页

作者： Eun Yim Cho jinsu Kim Sungsoo Rhim Dept. of Mech. Eng. Kyung Hee University

To increase the competition of the solar energy collection system, the size of the solar panel module during the manufacturing process is being increased continuously. As the size of the solar panel increases, the size of the robot to handle the panel increased also. The change in scale of the robot inevitably results ill the amplification of the adverse effect of tile flexure. The main source of the flexure in the large scale solar cell panel handling system is the long and thin fork fingers of the [land and the solar cell panel. In addition, tile belt-driven actuator system used by most of the large scale panel handling robot is another significant source of the vibration. In this paper, the flexible multi body dynamic model of a large scale solar cell panel handling robot, which is being designed and constructed with the help of Kyung Hee University, is developed. The belt-driven system in the robot is also modeled as flexible system and included ill the robot to represent the actual vibration characteristics of the actuator system. C 2013 The Chinese Society of Theoretical and Applied Mechanics. [doi： 10.1063/2.1301310]

关键词： flexible belt drive flexible multi body dynalnics modeling panel handling robot

Secure Key Management Based Mobile Authentication in Cloud

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Computer Systems Science & Engineering 2022年第12期43卷 887-896页

作者： S.Shanmuga Priya D.Yuvaraj T.Satyanarayana Murthy varghese S.Chooralil S.Navaneetha Krishnan P.Banumathy P.SundaraVadivel Department of Computer Science and Engineering M.I.E.T Engineering CollegeTrichyTamilnaduIndia Department of Computer Science and Engineering Cihan UniversityDuhokKurdistan RegionIraq Department of Computer Science and Engineering Bapatla Engineering CollegeBapatlaAndhra PradeshIndia Department of Computer Science and Engineering Rajagiri School of Engineering and TechnologyKakkanadKeralaIndia Department Electronics and Communication Engineering SACS MAVMM Engineering CollegeMaduraiTamilnaduIndia Department of Information Technology Karaikal Polytechnic CollegeVarichikudy-KaraikalIndia Department of Computer Science and Engineering SACS MAVMM Engineering CollegeMaduraiIndia

Authentication is important to the security of user data in a mobilecloud environment. Because of the server’s user credentials, it is subject toattacks. To maintain data authentication, a novel authentication mechanism is proposed. It consists of three independent phases: Registration, login, and authentication and key agreement. The user registers with the Registration Center (RC)by producing a secret number that isn’t stored in the phone, which protects againstprivileged insider attacks. The user and server generate a nonce for dynamic useridentity and agree on a session secret key for safe communication. The passwordsare not stored on the computer or provided in plain text, they are resistant toreplay, guessing, and stolen verification attacks. The suggested protocol uses aone-way hash function and XOR operations, with the client having remote accessto a large number of servers over a secure communication channel. Concentrateson HMAC and SHA3 for Collision Free Hashing and to overcome length extension attacks. HMACs are substantially less affected by collisions than their underlying hashing algorithms alone. So adding an HMAC to an MD5 or SHA hashwould make it substantially more difficult to break via a rainbow table.

关键词： Registration center SIM IMEI

Antioxidant,anti-alpha-glucosidase and pancreatic beta-cell protective effects of methanolic extract of Ensete superbum Cheesm seeds

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Asian Pacific Journal of Tropical Biomedicine 2017年第2期7卷 121-125页

作者： Solomon Habtemariam George Kabakasseril varghese Pharmacognosy Research Laboratories&Herbal Analysis Services Medway School of ScienceUniversity of GreenwichChatham-MaritimeKent ME4 4TBUK Department of Botany St.Berchmans'CollegeChanganasseryKottayam 686101KeralaIndia

Objective: To investigate the antioxidant, anti-a-glucosidase and pancreatic b-cell protective potential of Ensete superbum(E. superbum) ***: A variety of in vitro assays including radical scavenging, reducing power potential, phenolic content determination, a-glucosidase assay and pancreatic b-cell(1.4E7 cells) viability were employed for assessing the effect of methanolic extract of E. superbum ***: The radical scavenging and reducing power effects comparable with the standard rutin were obtained while the enzyme inhibitory activity of the extract was 68-fold better than the standard antidiabetic drug, acarbose. The seed extract of E. superbum was packed-full of polyphenols with mean percentage gallic acid equivalent value of(38.2 ± 1.8)(n = 3). The protection of pancreatic cells from massive onslaught of hydrogen peroxide was far superior to that obtained for ***: The reputed antidiabetic therapeutic uses of the seeds extract of E. superbum may be justified on the basis of inhibition of carbohydrate enzymes, antioxidant effects and pancreatic b-cell protection.

关键词： Ensete superbum Musaceae Seeds Antioxidant Pancreatic beta-cell protection Alpha-glucosidase inhibition

基于激光熔覆的镍基复合涂层制备方法与性能研究

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应用激光 2023年第10期43卷 90-96页

作者：于津苏何声馨郑州大学机械与动力工程学院河南郑州450001

提出一种在轴类零件表面,通过激光熔覆技术制备颗粒增强的Ti/B_(4)C/dr40复合涂层的方法。研究和分析复合涂层中陶瓷颗粒的生成机制以及对晶粒的细化作用,柱状晶向等轴晶的转变过程,涂层表面裂纹产生的原因以及温度梯度和凝固速率对涂... 详细信息

提出一种在轴类零件表面,通过激光熔覆技术制备颗粒增强的Ti/B_(4)C/dr40复合涂层的方法。研究和分析复合涂层中陶瓷颗粒的生成机制以及对晶粒的细化作用,柱状晶向等轴晶的转变过程,涂层表面裂纹产生的原因以及温度梯度和凝固速率对涂层显微组织的影响规律。为分析涂层的机械性能,对涂层进行硬度、压痕和划痕试验。结果表明,复合涂层与基体具有良好的冶金结合性能,凝固过程中生成的TiC和TiB_(2)硬质颗粒在磨损过程中起到骨架支撑作用,抑制基体的变形,降低材料去除率,提高了涂层的硬度和抗磨损性能。研究表明,通过激光熔覆技术制备的镍基复合涂层可以实现轴类零件的表面强化和再制造,具有良好的应用前景。

关键词：激光熔覆轴类零件镍基复合涂层表面强化

Quality of life after surgical and endoscopic management of severe acute pancreatitis: A systematic review

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World Journal of Gastrointestinal Endoscopy 2022年第7期14卷 443-454页

作者： Emmanouil Psaltis Chris varghese Sanjay Pandanaboyana Manu Nayar Department of HPB and Transplant Surgery Newcastle upon Tyne NE77DNUnited Kingdom Department of Surgery Freeman HospitalNewcastle upon Tyne NE77DNUnited Kingdom Department of Surgery Faculty of Medical and Health SciencesUniversity of AucklandAuckland 1010New Zealand Population Health Sciences Institute Newcastle UniversityNewcastle upon Tyne NE17RUUnited Kingdom Department of Gastroenterology Freeman HospitalNewcastle upon Tyne NE77DNUnited Kingdom

BACKGROUND Treatment for severe acute severe pancreatitis(SAP)can significantly affect Health-related quality of life(HR-QoL).The effects of different treatment strategies such as endoscopic and surgical necrosectomy on HR-QoL in patients with SAP remain poorly *** To critically appraise the available evidence on HR-QoL following surgical or endoscopic necrosectomy in patient with *** A literature search was performed on PubMed,Google^(TM) Scholar,the Cochrane Library,MEDLINE and Reference Citation Analysis databases for studies that investigated HR-QoL following surgical or endoscopic necrosectomy in patients with *** collected included patient characteristics,outcomes of interventions and HR-QoL-related *** Eleven studies were found to have evaluated HR-QoL following treatment for severe acute pancreatitis including 756 *** studies were randomized trials,four were prospective cohort studies and four were retrospective cohort studies with prospective *** studies compared HR-QoL following surgical and endoscopic *** metrics of HR-QoL were used including Short Form(SF)-36 and *** randomized trial and one cohort study demonstrated significantly improved physical scores at three months in patients who underwent endoscopic necrosectomy compared to surgical *** prospective study that examined HR-QoL following surgical necrosectomy reported some deterioration in the functional status of the *** the other hand,a cohort study that assessed the long-term HR-QoL following sequential surgical necrosectomy stated that all patients had SF-36>60%.In the only study that examined patients following endoscopic necrosectomy,the HR-QoL was also very *** studies investigated the quality adjusted life years suggesting that endoscopic and surgical approaches to management of pancreatic necrosis were comparable in cost ***,regarding HR-QoL between open necrose

关键词： Acute pancreatitis Pancreatic necrosis Surgical necrosectomy Endoscopic necrosectomy Minimally invasive drainage Quality of life

Spectroscopic studies of gel-grown lanthanum malonate crystals

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Journal of Rare Earths 2012年第3期30卷 245-249页

作者： varghese Mathew Sabu Jacob Lizymol Xavier K.E.Abraham Department of Physics St.Aloysius'CollegeEdathua-689573India Department of Physics S.B.CollegeChanganacherry-686101India

Lanthanum malonate crystals were grown by single tube ionic diffusion through silica gel. The crystallinity of the grown crystals was analyzed by powder X-ray diffraction studies. Fourier transform infrared spectroscopy （FTIR） and fourier transform （FT） Raman studies confirmed the presence of functional groups in the title compound. The optical band gap energy of the material was extracted from diffuse reflectance spectrum.

关键词： lanthanum malonate crystal growth X-ray diffraction analysis DRS studies FTIR and FT Raman studies rare earths

An Improved Steganographic Scheme Using the Contour Principle to Ensure the Privacy of Medical Data on Digital Images

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Computer Systems Science & Engineering 2023年第8期46卷 1563-1576页

作者： R.Bala Krishnan D.Yuvaraj P.Suthanthira Devi varghese S.Chooralil N.Rajesh Kumar B.Karthikeyan G.Manikandan srinivasa ramanujan centre sastra deemed universitykumbakonamtamil naduindia department of computer science cihan university–duhokkurdistan regioniraq department of information technology st.joseph’s college of engineeringchennaitamil naduindia department of computer science&engineering rajagiri school of engineering&technologykakkanadkeralaindia school of computing sastra deemed universitythanjavurtamil naduindia

With the improvement of current online communication schemes,it is now possible to successfully distribute and transport secured digital Content via the communication channel at a faster transmission *** steganography and cryptography concepts are used to achieve the goal of concealing secret Content on a media and encrypting it before *** of the techniques mentioned above aid in the confidentiality of feature *** proposed approach concerns secret content embodiment in selected pixels on digital image layers such as Red,Green,and *** private Content originated from a medical client and was forwarded to a medical practitioner on the server end through the *** K-Means clustering principle uses the contouring approach to frame the pixel clusters on the image *** content embodiment procedure is performed on the selected pixel groups of all layers of the image using the Least Significant Bit(LSB)substitution technique to build the secret Content embedded image known as the stego image,which is subsequently transmitted across the internet medium to the server *** experimental results are computed using the inputs from“Open-Access Medical Image Repositories(***)”and demonstrate the scheme’s impudence as the Content concealing procedure progresses.

关键词： Contouring secret content embodiment least significant bit embedding medical data preservation secret content congregation pixel clustering

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硬毛巴豆减弱链脲佐菌素诱导大鼠的神经炎症

数字中医药(英文) 2023年第3期6卷 295-306页

作者： Prakash Ramakrishnan Jayaram Rajangam Binoy varghese Cherian Jose Prakash Dharmian Department of Pharmacology Crescent School of PharmacyB.S.Abdur Rahman Crescent Institute of Science and TechnologyChennaiTamil Nadu 600048India Department of Pharmacology Shri Venkateshwara College of PharmacyPondicherryTamil Nadu 605001India Department of Pharmaceutical Chemistry Saveetha College of PharmacyChennaiTamil Nadu 602117India Department of Pharmaceutics Crescent School of PharmacyB.S.Abdur Rahman Crescent Institute of Science and TechnologyChennaiTamil Nadu 600048India

目的本研究旨在探讨硬毛巴豆(CH)提取物在链脲佐菌素(STZ)大鼠中的神经保护作用。方法(1)亚慢性毒性试验包括24只成年大鼠,雌雄不限,体重160~200 g,分为4组,每组6只。第1组大鼠给予二甲基亚砜(DMSO)与生理盐水混合物;第2、3、4组大鼠灌... 详细信息

目的本研究旨在探讨硬毛巴豆(CH)提取物在链脲佐菌素(STZ)大鼠中的神经保护作用。方法(1)亚慢性毒性试验包括24只成年大鼠,雌雄不限,体重160~200 g,分为4组,每组6只。第1组大鼠给予二甲基亚砜(DMSO)与生理盐水混合物;第2、3、4组大鼠灌胃给药硬毛巴豆甲醇提取物(MECH),剂量分别为100、200和400 mg/kg,连续28天。将功能观察组合和自发活动分级作为其神经行为活动的一部分,并对脑区(如皮质和海马)进行神经病理学异常分析。(2)研究动物体重为160~200 g的成年雄性Wistar大鼠,分为5组,每组6只,包括对照组(Ⅰ)、STZ组(Ⅱ)、多奈哌齐组(Ⅲ)、MECH组(100 mg/kg,Ⅳ)和MECH组(200 mg/kg,Ⅴ)。第Ⅰ组大鼠口服柠檬酸盐缓冲液和DMSO生理盐水混合物(14天)。第Ⅱ组大鼠在第1天和第3天侧脑室注射链脲佐菌素(3 mg/kg,双侧ICV-STZ),随后给予生理盐水DMSO混合物(14天)。第Ⅲ、Ⅳ和Ⅴ组大鼠在第1天和第3天给予STZ,随后口服多奈哌齐[3 mg/(kg·d)]和MECH[100和200 mg/(kg·d)](14天)。检测大鼠Morris水迷宫(MWM)和被动回避试验(PAT)等学习记忆指标。完成行为学实验后处死动物,取脑,用紫外可见分光光度计测定乙酰胆碱酯酶(AChE)、脂质过氧化(LPO)、谷胱甘肽(GSH)和超氧化物歧化酶(SOD)水平。使用总荧光发射光谱法测定caspase-3水平。通过酶联免疫吸附测定(ELISA)检测β淀粉样蛋白(Aβ)水平,同时对CA1海马区进行组织病理学分析。结果(1)亚慢性毒性结果显示,各组MECH大鼠的旷场试验参数(包括线交叉、直立、进入中广场、排便或排尿)无显著差异(P>0.05)。组织病理学结果显示,与对照组大鼠相比,经过MECH治疗的大鼠两个区域的神经元细胞中均未产生任何病变和炎症。(2)研究主要发现STZ处理大鼠在学习和记忆参数受损显著增加(P<0.001),AChE、caspase-3、Aβ(1-40和1-42)和LPO水平均显著升高(P<0.001),且SOD和GSH水平显著降低(P<0.01)。此外,在海马区发现神经元损伤。相反,STZ诱导大鼠的行为和生化损伤与MECH治疗呈剂量依赖性降低。结论MECH通过其抗氧化作用可显著预防STZ诱导的记忆缺陷,胆碱能功能的恢复可能是行为改善的原因。因此,MECH可能治疗包括阿尔茨海默病在内的认知障碍。

关键词：神经炎症硬毛巴豆阿尔茨海默病链脲佐菌素脑室内