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Chinese Journal of Chemistry 2011年第4期29卷 745-750页

作者： Kamboj, ramesh C Kumar, Dinesh Sharma, Geeta Arora, Rita Department of Chemistry Kurukshetra University Kurukshetra 136119 India

Photo-irradiation of 2-（5-methylthiophen-2-yl）-3-[（naphthalen-2-yl）methoxy]-4H-chromen-4-ones yielded the fascinating angular tetracyclic products via cyclization involving both 2-thienyl ring and naphthylmethoxy group via 1,4-biradical generated in the Norrish type-II process. The stereochemical dispositions of the products were determined by MM2 energy minimized programme and spectroscopic analysis.

关键词： type-II reaction radicals thienylchromone sigmatropic rearrangement substituent effects

Photon condensation： A new paradigm for Bose-Einstein condensation

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Frontiers of physics 2016年第5期11卷 103-110页

作者： Renju Rajan P. ramesh Babu K. Senthilnathan Department of Physics School of Advanced Sciences VIT University Vellore Tamil Nadu 632015 India

Bose-Einstein condensation is a state of matter known to be responsible for peculiar properties exhibited by superfluid Helium-4 and superconductors. Bose-Einstein condensate （BEC） in its pure form is realizable with alkali atoms under ultra-cold temperatures. In this paper, we review the experimental scheme that demonstrates the atomic Bose-Einstein condensate. We also elaborate on the theoretical framework for atomic Bose-Einstein condensation, which includes statistical mechan- ics and the Gross-Pitaevskii equation. As an extension, we discuss Bose-Einstein condensation of photons realized in a fluorescent dye filled optical microcavity. We analyze this phenomenon based on the generalized Planck＇s law in statistical mechanics. Further, a comparison is made between photon condensateand laser. We describe how photon condensate may be a possible alternative for lasers since it does not require an energy consuming population inversion process.

关键词： Bose-Einstein condensation photon condensation magneto-optical trap Gross-Pitaevskii equation Planck's radiation law

Measurement of bit-rock interface temperature and wear rate of the tungsten carbide drill bit during rotary drilling

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Friction 2020年第6期8卷 1073-1082页

作者： Vijay Kumar SHANKAR Bijay Mihir KUNAR Chivukula Suryanarayana MURTHY M R ramesh Department of Mining Engineering National Institute of Technology KarnatakaSurathkal 575025India Department of Mechanical Engineering National Institute of Technology KarnatakaSurathkal 575025India

Rock drilling is an essential operation in mining *** at the bit-rock interface plays a major role in the wear rate of the drill *** paper primarily focuses on the wear rate of tungsten carbide(WC)drill bit and the interrelationship between temperature and wear rate during rotary drilling operations conducted using a computer numerical control(CNC)*** interrelationship between the temperature and wear rate was studied with regard to three types of rock samples,i.e.,fine-grained sandstone(FG)of uniaxial compressive strength(UCS)that is 17.83 MPa,medium-grained sandstone(MG)of UCS that is 13.70 MPa,and fine-grained sandstone pink(FGP)of UCS that is 51.67 *** rate of the drill bit has been measured using controlled parameters,i.e.,drill bit diameter(6,8,10,12,and 16 mm),spindle speed(250,300,350,400,and 450 rpm),and penetration rate(2,4,6,8,and 10 mm/min),***,a fully instrumented laboratory drilling set-up was *** weight of each bit was measured after the bit reached 30 mm depth in each type of the rock ***,effects of the bit-rock interface temperature and operational parameters on wear rate of the drill bits were *** results show that the wear rate of drill bits increased with an increase in temperature for all the bit-rock combinations *** is due to the silica content of the rock sample,which leads to an increase in the frictional heat between the bit-rock ***,in case of medium-grained sandstone,the weight percentage(wt%)of SiO2 is around 7.23 wt%,which presents a very low wear rate coefficient of 6.33×10^–2 mg/(N?m).Moreover,the temperature rise during drilling is also minimum,i.e.,around 74℃,in comparison to that of fine-grained sandstone and fine-grained sandstone *** addition,this paper develops the relationship between temperature and wear rate characteristics by employing simple linear regression analysis.

关键词： temperature wear rate drilling simple linear regression

Exploring the sublethal genotoxic effects of class II organophosphorus insecticide quinalphos on freshwater fish Cyprinus carpio

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Journal of Oceanology and Limnology 2021年第2期39卷 661-670页

作者： Devan HEMALATHA Bojan NATARAJ Basuvannan RANGASAMY Kannan MAHARAJAN Mathan ramesh Unit of Toxicology Department of ZoologySchool of Life SciencesBharathiar UniversityCoimbatore-641046Tamil NaduIndia Department of Zoology PSG College of Arts&ScienceCoimbatore-641014Tamil NaduIndia

The genotoxic effects of quinalphos(QP)were evaluated in the erythrocytes of Cyprinus carpio using the comet,micronucleus,and nuclear abnormality *** 96 h LC_(50) value of quinalphos,estimated by static renewal system,was 10.9µL/*** the basis of the LC_(50) value,two sublethal concentrations(1.09 and 2.18µL/L)of the compound were used together with cyclophosphamide(5 mg/L)as the positive *** fish were exposed for 35 d,and sampling was done at the end of 7,14,21,28,and 35 *** results reveal a significant dose-dependent increase in the frequencies of DNA strand breaks,micronucleus,and nuclear *** responses were also observed in fish exposed to the positive genotoxin *** collective findings demonstrated that quinalphos exerts a genotoxic effect on *** results further confirmed that the comet,micronucleus,and nuclear abnormality assays are useful tools in determining the potential genotoxicity of pesticides towards aquatic organisms.

关键词： quinalphos(QP) micronucleus nuclear abnormalities cyclophosphamide Cyprinus carpio

Frequency equation for the submicron CMOS ring oscillator using the first order characterization

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Journal of Semiconductors 2018年第5期39卷 64-69页

作者： Aravinda Koithyar T.K.ramesh Department of Electronics and Communication Engineering Amrita School of Engineering

By utilizing the first order behavior of the device,an equation for the frequency of operation of the submicron CMOS ring oscillator is presented.A 5-stage ring oscillator is utilized as the initial design,with different Beta ratios,for the computation of the operating *** on,the circuit simulation is performed from 5-stage till 23-stage,with the range of oscillating frequency being 3.0817 and 0.6705 GHz *** is noted that the output frequency is inversely proportional to the square of the device length,and when the value of Beta ratio is used as 2.3,a difference of 3.64%is observed on an average,in between the computed and the simulated values of *** an outcome,the derived equation can be utilized,with the inclusion of an empirical constant in general,for arriving at the ring oscillator circuit’s output frequency.

关键词： ring oscillator stage delay SPICE model RC model second order effects

Studies on activity of various extracts of Mentha arvensis Linn against drug induced gastric ulcer in mammals

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World Journal of Gastrointestinal Oncology 2009年第1期1卷 82-88页

作者： ramesh L Londonkar Pramod V Poddar Department of Studies and Research in Biotechnology Gulbarga University

AIM:To examine the antiulcerogenic effects of various extracts of Mentha arvensis Linn on acid,ethanol and pylorus ligated ulcer models in rats and ***:Various crude extracts of petroleum ether,chloroform,or aqueous at a dose of 2 g/kg po did not produce any signs or symptoms of toxicity in treated *** the pyloric ligation model oral administration of different extracts such as petroleum ether,chloroform and aqueous at 375 mg/kg po,standard drug ranitidine 60 mg/kg po and control group 1 Tween 80,5 mL/kg po to separate groups of Wister rats of either sex(n = 6) was *** acidity,ulcer number,scoring,incidence,area,and ulcer index were ***:There was a decrease in gastric secretion and ulcer index among the treated groups *** ether(53.4),chloroform(59.2),aqueous(67.0) and in standard drug(68.7) when compared to the negative *** the 0.6 mol/L HCl induced ulcer model in rats(n = 6) there was a reduction in ulcerative score in animals receiving petroleum ether(50.5),chloroform(57.4),aqueous(67.5) and ***(71.2) when compared to the negative *** the case of the 90 ethanol-induced ulceration model(n = 6) in mice,there was a decrease in ulcer score in test groups of petroleum ether(53.11),chloroform(62.9),aqueous(65.4) and standard drug ranitidine(69.7) when compared to the negative *** was found that pre-treatment with various extracts of Mentha arvensis Linn in three rat/mice ulcer models ie ibuprofen plus pyloric ligation,0.6 mol/L HCl and 90 ethanol produced significant action against acid secretion(49.3 ± 0.49 vs 12.0 ± 0.57,P < 0.001).Pre-treatment with various extracts of Mentha arvensis Linn showed highly-significant activity against gastric ulcers(37.1 ± 0.87 vs 12.0 ± 0.57,P < 0.001).CONCLUSION:Various extracts of Mentha arvensis Linn.375 mg/kg body weight clearly shows a protective effect against acid secretion and gastric ulcers in ibuprofen plus pyloric ligation,0.6 mol/L HCl induced

关键词： Mentha arvensis Anti ulcer Gastroprotection Medicinal plant

Effects of Froude number and geometry on water entry of a 2-D ellipse

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Journal of Hydrodynamics 2018年第4期30卷 738-749页

作者：张旭刘沛清屈秋林王睿 ramesh K.Agarwal School of Aeronautic Science and Engineering Beihang University School of Engineering and Applied Science Washington University in St.Louis

By using the finite volume method with volume of fluid model and global dynamic mesh technique, the effects of Froude number and geometry on the water entry process of a 2-D ellipse are investigated numerically. For the time history of the vertical force, the computational fluid dynamics（CFD） results match the experimental data much better than the classical potential-flow theories due to the consideration of the viscosity, turbulence, surface tension, gravity, and compressibility. The results show that the position of peak pressure on ellipse shifts from the spray root to the bottom of ellipse at a critical time. The critical time changes with the geometry and Froude number. By studying the vertical force, the ellipse water entry process can be divided into the initial and late stages based on the critical dimensionless time of about 0.1. The geometry of the ellipse plays a dominant role in the initial stage, while the Froude number is more important in the late stage of entry. The classical Wagner theory is extended to the ellipse water entry, and the predicted maximum value of vertical force coefficient in the initial stage is 4？a/b that matches the CFD results very well, where a and b are the horizontal axis and vertical axis of the ellipse parallel and perpendicular to the initial calm water surface, respectively.

关键词： Water impact water entry fluid-structure interaction Froude number

Dietary salt in liver cirrhosis:With a pinch of salt!

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World Journal of Hepatology 2023年第10期15卷 1084-1090页

作者： ramesh Kumar Sudheer Marrapu Department of Gastroenterology All India Institute of Medical SciencesPatna 801507India

Patients with liver cirrhosis are advised to limit their sodium consumption to control excessive fluid *** is the most common form in which sodium is consumed ***,various recommendations urge patients to limit salt ***,there is a lack of consistency regarding salt restriction across the ***,there is conflicting evidence regarding the efficacy of salt restriction in the treatment of *** studies have shown that there is no difference in ascites control between patients with restriction of salt intake and those without ***,patients with cirrhosis may have several negative effects from consuming too little salt,although there are no recommendations on the lower limit of salt *** is necessary to maintain the extracellular fluid volume;hence,excessive salt restriction can result in volume contraction,which could negatively impact kidney function in a cirrhotic *** restriction in cirrhotic patients can also compromise nutrient intake,which can have a negative impact on the overall *** is insufficient evidence to recommend restricted salt intake for all patients with cirrhosis,including those with severe *** existing guidelines on salt restriction do not consider the salt sensitivity of patients;their nutritional state,volume status and sodium storage sites;and the risk of *** opinion article aims to critically analyze the existing literature with regard to salt recommendations for patients with liver cirrhosis and identify potential knowledge gaps that call for further research.

关键词： Salt Cirrhosis Sodium Hyponatremia Ascites Malnutrition

Highly flexible conductive fabrics with hierarchically nanostructured amorphous nickel tungsten tetraoxide for enhanced electrochemical energy storage

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Nano Research 2015年第12期8卷 3749-3763页

作者： Goli Nagaraju ramesh Kakarla Sung Min Cha Jae Su Yu Department of Electronics and Radio Engineering Institute for Wearable Convergence Electronics Kyung Hee University 1 Seocheon-dong Giheung-gu Yongin-si Gyeonggi-do 446-701 Republic of Korea Department of Environmental Science and Engineering Kyung Hee University 1Seocheon-dong Giheung-gu Yongin-si Gyeonggido 446-701 Republic of Korea

Amorphous nickel tungsten tetraoxide （NiWO4） nanostructures （NSs） were successfully synthesized on a flexible conductive fabric （CF） using a facile one- step electrochemical deposition （ED） method. With an applied external cathodic voltage （-1.8 V for 15 min）, the amorphous NiWO4 NSs with burl-like morphologies adhered well on the seed-coated CF substrate. The burMike amorphous NiWO4 NSs on CF （NiWO4 NSs/CF） are employed as a flexible and binder-free electrode for pseudocapacitors, which exhibit remarkable electrochemical properties with high specific capacitance （1,190.2 F/g at 2 A/g）, excellent cyclic stability （92% at 10 A/g）, and good rate capability （765.7 F/g at 20 A/g） in 1 M KOH electrolyte solution. The superior electrochemical properties can be ascribed to the hierarchical structure and large specific surface area of the burl-like amorphous NiWO4 NSs/CF. This cost-effective facile method for the synthesis of metal tungsten tetraoxide nanomaterials on a flexible CF could be promising for advanced electronic and energy storage device applications.

关键词： amorphous NiWO4 nanostructures conductive fabrics electrochemical deposition electrochemical energystorage properties

Synthesis, characterization and biocompatibility studies of zinc oxide(ZnO) nanorods for biomedical application

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Nano-Micro Letters 2010年第1期2卷 31-36页

作者： R.Gopikrishnan K.Zhang P.Ravichandran S.Baluchamy V.ramesh S.Biradar P.ramesh J.Pradhan J.C.Hall A.K.Pradhan G.T.ramesh Molecular Toxicology Laboratory Center for Biotechnology and Biomedical Sciences Norfolk State University Center for Materials Research Norfolk State University Health Science Academy Bayside High School Virginia Beach

Nanoparticles are increasingly being recognized for their potential utility in biological applications including ***,we have synthesized zinc oxide(ZnO)nanorods using zinc acetate and hexamethylenetetramine as precursors followed by characterizing using X-ray diffraction,fourier transform infrared spectroscopy,scanning electron microscopy and transmission electron *** growth of synthesized zinc oxide nanorods was found to be very close to its hexagonal nature,which is confirmed by X-ray *** nanorod was grown perpendicular to the long-axis and grew along the[001]direction,which is the nature of ZnO *** morphology of synthesized ZnO nanorods from the individual crystalline nucleus was confirmed by scanning and transmission electron *** length of the nanorod was estimated to be around 21 nm in diameter and 50 nm in *** toxicology studies showed that synthesized ZnO nanorods exposure on hela cells has no significant induction of oxidative stress or cell death even in higher concentration(10μg/ml).The results suggest that ZnO nanorods might be a safer nanomaterial for biological applications.

关键词： Zinc oxide [ZnO] Nanorods XRD SEM & TEM Cytotoxicity