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International Journal of Otolaryngology and Head & Neck Surgery 2021年第6期10卷 511-518页

作者： Gvs rao Laxminath Ganji chaitanya rao chaitanya rao Shree rao Prudviraju Moganti Monalisa Hui Shantveer G. Uppin ch Tejaswini Dr raos ENT Superspeciality International Hospital Hyderabad India Nizam’s Institute of Medical Sciences Hyderabad India Basavatarakam Indo American Cancer Hospital & Research Institute Hyderabad India

Introduction: Unilateral nasal mass can be benign or malignant. Very rarely we will find benign salivary gland tumor in nasal cavity. Pleomorphic adenoma is still the most common pathological variety either in major or minor salivary gland tumors. In the nasal cavity, even though most of the accessory salivary glands are present in the lateral wall of nose, nasal septum remains the most common site of origin. Case Report: A 40-year-old female presented with right-sided nasal obstruction and epistaxis. CT scan of Nose and Paranasal sinuses found a lesion involving the anterior third of the right nasal cavity. The patient underwent complete surgical resection of the tumor via an endonasal approach. Histological examination found a mixed cellular component (epithelial and myoepithelial) and mesenchymatous tissue with chondromyxoid stroma, enabling diagnosis of a typical pleomorphic adenoma. Conclusion: Pleomorphic adenoma is the most common salivary gland tumor but rare to find in the nasal cavity with only few cases reported in the literature. Although benign, the risk of local recurrence, malignant transformation and metastasis requires close long-term follow-up.

关键词： Pleomorphic Adenoma (PA) Benign Salivary Gland Tumour Nasal Mass Nasal Septum

Electrochemical process of titanium extraction

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中国有色金属学会会刊：英文版 2007年第2期17卷 429-433页

作者： ch. RVS. NAGESH C. S. RAMAchANDRAN Defence Metallurgical Research Laboratory HyderabadA.P. India-500058

A wide variety of processes are being pursued by researchers for cost effective extraction of titanium metal. Electrochemical processes are promising due to simplicity and being less capital intensive. Some of the promising electrochemical processes of titanium extraction were reviewed and the results of laboratory scale experiments on electrochemical reduction of TiO2 granules were brought out. Some of the kinetic parameters of the reduction process were discussed while presenting the quality improvements achieved in the experimentation.

关键词：钛萃取电化学还原过程动力学参数

A Perceptual Approach to Reduce Musical Noise Using Critical Bands Tonality Coefficients and Masking Thresholds

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International Journal of Communications, Network and System Sciences 2009年第8期2卷 742-745页

作者： ch. V. Rama rao M. B. Rama Murthy K. Srinivasa rao 不详

Traditional noise reduction techniques have the drawback of generating an annoying musical noise. A new scheme for speech enhancement in high noise environment is developed by considering human auditory system masking characteristics. The new scheme considers the masking threshold of both noisy speech and the denoised one, to detect musical noise components. To make them inaudible, they are set under the noise masking threshold. The improved signal is subjected to extensive subjective and objective tests. It is ob-served that the musical noise is appreciably reduced even at very low signal to noise ratios.

关键词： Noise Reduction Musical Noise Masking Threshold

Vibrational Spectroscopy of ch/CD Stretches in Propadiene： An Algebraic Approach

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chinese Physics Letters 2009年第2期26卷 36-38页

作者： Joydeep choudhury Nirmal Kumar Sarkar Srinivasa rao Karumuri Ramendu Bhattacharjee Department of Physics Assam University Silchar- 788011 India Department of Physics Karimganj College Karimganj-788710 India

Using Hamiltonian based on Lie algebraic method, the stretching vibrational modes of C3H4 and C3D4 molecules are calculated up to higher overtones. The model appears to describe C-H and C-D stretching modes with less number of parameters. The locality parameter ξ confirms the highly local behaviour of the stretching modes of these molecules.

关键词： No English Keywords

Study of Technology of Stripping Nickel Coating on NdFeB Permanent Magnet

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Journal of Rare Earths 2004年第Z1期22卷 115-117页

作者： rao Houzeng Li Guohua Jiang Longfa Lin Guanjie Department of Environmental and chemical Engineering Nanchang Institute of Aeronautical TechnologyNanchang 330034 China Jiangxi Hengda Group Nanchang 330029 China Department of Environmental and Chemical Engineering Nanchang Institute of Aeronautical TechnologyNanchang 330034 China Department of Environmental and Chemical Engineering Nanchang Institute of Aeronautical TechnologyNanchang 330034 China

The influences of category and density of reagents, temperature and the value of pH in the solution of stripping the nickel coating on NdFeB permanent magnet on the stripping result were studied *** practical formular contains mainly the oxidant m-O2NC6H4SO3Na, the complex reagent ( NaOOCch2 ) 2N( ch2 ) 2N( ch2COOH)2,the reagent of retarding corrosion KF and the calatyze RL-3 was obtained.

关键词： NdFeB permanent magnet base stripping nickel coating reagent of retarding corrosion calatyze

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chinese Journal of Aeronautics 2023年第5期36卷 18-32页

作者： Zhuming rao Ruichao LI Peizhe ZHAO Bing WANG Dan ZHAO Qiaofeng XIE School of Aerospace Engineering Tsinghua UniversityBeijing 100084China Department of Mechanical Engineering University of CanterburyChristchurch 8041New Zealand

In this study,flame responses to acoustic disturbances with different frequencies and amplitudes were experimentally investigated in a lean premixed swirl-stabilized combustor operating at different bulk *** total heat release rate fluctuations and spatial ch*chemiluminescence distributions were captured using a photomultiplier tube and high-speed camera,*** results indicate that the heat release rate exhibits a relatively drastic oscillation and high-order harmonics for low-frequency *** the bulk velocity and forcing frequency were doubled simultaneously,similar flame structures were observed in the ch*chemiluminescence *** the bulk velocity increases,the gain of the Flame Describing Function(FDF)extends toward the higher frequencies,and the delay time of the flame response *** similarity among FDFs at different bulk velocities was effectively captured by introducing a non-dimensional parameter,defined as the ratio of the flame response delay to the forcing time scale,to replace the dimensional forcing ***,the availability of the newly defined non-dimensional parameter was verified for flames with different swirl numbers,as this played an important role in determining the flame structures and associated unsteady heat release rate.

关键词： Bulk velocity Combustion instability Flame describing function Strouhal number Swirling flame Swirl number

Macro and micro issues in turbulent mixing

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Science china(Technological Sciences) 2013年第10期56卷 2355-2360页

作者： MELVIN J KAUFMAN R LIM H KAMAN T rao P GLIMM J Department of Applied Mathematics and Statistics Stony Brook UniversityStony Brook NY 11794 USA

Numerical prediction of turbulent mixing can be divided into two subproblems: to predict the geometrical extent of a mixing region and to predict the mixing properties on an atomic or molecular scale, within the mixing region. The former goal suffices for some purposes, while important problems of chemical reactions(e.g. flames) and nuclear reactions depend critically on the second goal in addition to the first one. Here we review recent progress in establishing a conceptual reformulation of convergence, and we illustrate these concepts with a review of recent numerical studies addressing turbulence and mixing in the high Reynolds number limit. We review significant progress on the first goal, regarding the mixing region, and initial progress on the second goal, regarding atomic level mixing properties. New results concerning non-uniqueness of the infinite Reynolds number solutions and other consequences of a renormalization group point of view, to be published in detail elsewhere, are summarized *** notion of stochastic convergence(of probability measures and probability distribution functions) replaces traditional pointwise convergence. The primary benefit of this idea is its increased stability relative to the statistical "noise" which characterizes turbulent flow. Our results also show that this modification of convergence, with sufficient mesh refinement, may not be needed. However, in practice, mesh refinement is seldom sufficient and the stochastic convergence concepts have a *** to this circle of ideas is the observation that turbulent mixing, in the limit of high Reynolds number, appears to be non-unique. Not only have multiple solutions been observed(and published) for identical problems, but simple physics based arguments and more refined arguments based on the renormalization group come to the same *** of the non-uniqueness inherent in numerical models of high Reynolds number turbulence and mixing, we also include here numeri

关键词： stochastic convergence turbulent mixing renormalization group dynamic subgrid scale models

The Portevin-Le chatelier effect of gradient nanostructured 5182 aluminum alloy by surface mechanical attrition treatment

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Journal of Materials Science & Technology 2018年第12期34卷 2307-2315页

作者： Xiangchen Meng Bei Liu Lan Luo Yan Ding Xi-Xin rao Bin Hu Yong Liu Jian Lu Key Laboratory of Lightweight and High Strength Structural Materials of Jiangxi Province Nanchang University School of Materials Science & Engineering Nanchang University china Science Lab. General Motors Research & Development Department of Mechanical and Biomedical Engineering City University of Hong Kong Centre for Advanced Structural Materials City University of Hong KongShenzhen Research Institute

Nanocrystalline surface layers and gradient nanostructure in 5182 aluminum alloy have been produced through surface mechanical attrition treatment(SMAT). The results indicate that the gradient nanostructure can not only improve the mechanical properties of 5182 Al alloy, but also has a certain effect on the Portevin-Le chatelier(PLC) effect. The yield and ultimate tensile strength of 5182 Al alloy with SMAT are significantly improved combining with the decrease of fracture elongation compared with the as-received one. The PLC effect of 5182 Al alloy could be effectively postponed by the formation of gradient nanostructure after SMAT. It leads to the increase of critical strain of the PLC effect, more concentrated distribution of serrated strain, and increase of average stress amplitude in special strain range. The influence of grain size and gradient nanostructure on the PLC effect of 5182 Al alloy was also discussed in detail. Grain refinement could sharply increase the density of dislocations and hinder the movement of dislocations, which results in the decrease of moving speed of dislocations and the more concentrated distribution of solute atoms. The solute atoms would aggregate to form nano precipitates and further impede movement of dislocation. The stronger interaction between the dislocations and the nano precipitates is the main mechanism of postponed PLC effect.

关键词： Aluminum alloy Portevin-Le chatelier effect Serrated yielding Surface mechanical attrition treatment Gradient nanostructure

Transformation of User Interface to Activity Models and Assessing Performance of WA/WS

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Journal of Software Engineering and Applications 2019年第5期12卷 101-126页

作者： ch. Ram Mohan Reddy D. Evangelin Geetha R. V. Raghvendra rao T. V. Suresh Kumar B.M.S College of Engineering Bengaluru India Ramaiah Institute of Technology Bengaluru India

Quality of Service is an important attribute of a software system. In retrospect, performance assessment based on user interaction with the system has given a better understanding of underlying disciplines of the product. In this paper, we capture user interaction with the prototype/User Interface (UI). An approach for developing activity model from the user interface model is presented using workflows and functional elements. A methodology is proposed to transform UI into activity diagram. The approach is validated by an experimental setup using Amazon service. The performance of Amazon service is assessed using activity based performance prediction methodology, and the simulation results are obtained using SMTQA.

关键词： Web Services Software Performance Engineering Web Applications Software Size Estimation Activity Based Performance Prediction Unified Modeling Language

Selective Hydrogenation of Polycyclic Aromatics to Monocyclic Aromatics over NiMoC/HβCatalysts in a Methane and Hydrogen Environment

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china Petroleum Processing & Petrochemical Technology 2023年第2期25卷 92-100页

作者： Shen Zhibing Fu rao Zhang Shangli Wang Shunmei Zhang Wu Tang Ruiyuan Liang Shengrong Zhang Juntao Yuan Shibao Jiang Haiyan Xi’an Key Laboratory of Low-carbon Utilization for High-carbon Resources College of Chemistry and Chemical EngineeringXi’an Shiyou UniversityXi’anShaanxi 710065China Shaanxi Engineering Research Center of Green Low-carbon Energy Materials and Processes Xi’an Shiyou UniversityXi’anShaanxi 710065China College of Petroleum Engineering Xi’an Shiyou UniversityXi’anShaanxi 710065China

To obtain high yields of monocyclic aromatic hydrocarbons with methyl side chains,such as toluene and xylene,methane(ch_(4))can be introduced into the hydrocracking of polycyclic aromatic ***_(4)can participate in the reaction,supply methyl side chains to the product,and improve product *** this study,the hydrogenation reaction of polycyclic aromatic hydrocarbons over a carbonized NiMo/Hβcatalyst in a ch_(4)and hydrogen(H_(2))environment was investigated to study the promotional effect of ch_(4)on the hydrocracking of polycyclic *** conditions of 3.5 MPa,380℃,volume air velocity of 4 h^(-1),gas-oil volume ratio of 800,and H_(2):ch_(4)molar ratio of 1:1,the conversion rate of naphthalene was 99.97%,the liquid phase yield was 93.62%,and the selectivity of BTX were 17.76%,25.17%,and 20.47%,*** comparison to the use of a H_(2)atmosphere,the selectivity of benzene was significantly decreased,whereas the selectivity of toluene and xylene were *** was shown that ch_(4)can participate in the hydrocracking of naphthalene and improve the selectivity of toluene and xylene in the liquid *** carbonized NiMo/Hβcatalyst was characterized by a range of analytical methods(such as X-ray diffraction(XRD),ammonia-temperature-programmed desorption(NH3-TPD),hydrogen-temperature-programmed reduction(H_(2)-TPR),and X-ray photoelectron spectroscopy(XPS)).The results indicated that Ni and Mo carbides were the major species in the carbonized NiMo/Hβcatalyst and were considered to be active sites for the activation of ch_(4)and H_(2).After loading the metal components,the catalyst displayed prominent weak acidic sites,which may be suitable locations for cracking,alkylation,and other related ***,the carbonized NiMo/Hβcatalyst displayed multiple functions during the hydrocracking of polycyclic aromatic hydrocarbons in a ch_(4)and H_(2)*** results could be used to develop a new way to efficiently utiliz

关键词： methane polycyclic aromatic hydrocarbons hydrocracking NiMoC/Hβ toluene xylene