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An ab initio study of strained two-dimensional MoSe_2

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Journal of Semiconductors 2015年第4期36卷 11-15页

作者： Bahniman Ghosh naval Kishor Microelectronics Research Center 10100 Burnet RoadBldg. 160University of Texas at Austin Department of Electrical Engineering Indian Institute of Technology Kanpur

We have studied the electronic properties of molybdenum diselenide （MoSe2） in both bulk and mono- layer （zigzag and armchair） forms using density function theory. The metallic nature of the zigzag MoSe2 （ZMoSe2） nanoribbon and the semiconducting behavior of the armchair MoSe2 （AMoSe2） nanoribbon have been explored us- ing a band structure calculated using self-consistent calculations. We have also studied the variation in the bandgap in the presence of a small amount of strain （uniaxial, biaxial）. The effect of tensile strain has been investigated and shifts in the conduction band and valance band have been observed with different amounts of applied strain.

关键词： MoSe2 band structure self-consistent calculations

Integrated approach of heavy metal pollution indices and complexity quantification using chemometric models in the Sirsa Basin, Nalagarh valley, Himachal Pradesh, India

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Chinese Journal Of Geochemistry 2015年第4期34卷 620-633页

作者： Rajkumar Herojeet Madhuri S.Rishi naval Kishore Department of Environment Studies Panjab University Department of Geology (CAS) Panjab University

Chemometric techniques and pollution assessment indices were applied to determine the source and intensity of pollution in the Sirsa River, Himachal Pradesh,India. Results show EC, Cr, Fe, Mn, and Ni were above the permissible limit as per the Bureau of Indian *** heavy metal pollution index(HPI) and contamination index(Cd) provided contrasting outcome and poor correlation was observed. A heavy metal evaluation index(HEI)method was developed using a multiple of the mean and correlation coefficient values to provide an alternative pollution classification. The criteria of HEI adopted for reclassification of HPI and Cdproduced comparable results; 40 % samples were labeled as low contamination,50 % as medium contamination, and 10 % as high contamination for all indices. Principal component analysis along with cluster analysis was used to identify the main factors responsible for degradation of water quality,namely discharge of industrial effluent, river bed mining,agricultural runoff, and minor natural or geogenic *** methods and chemometric study proposed here can be used as effective tools to gather information about water quality and water resource management.

关键词：化学计量学污染指数评价指标重金属印度盆地模型锡

PASSIVE-ACTIVE CONTROL OF POWER FLOW IN AN ISOLATION SYSTEM MOUNTED ON FLEXIBLE FOUNDATIONS

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Chinese Journal of Mechanical Engineering 2001年第2期14卷 111-115页

作者： Huo Rui Shi Yin Institute of naval Ship Equipment Noise & Vibration, naval University of Engineering Song Kongjie Shandong University of Technology 解放军海军工程大学动力工程学院湖北武汉山东工业大学山东

A general model of flexible isolation systems which involves both the passive and active control factors is established by inserting actuators into an passive isolation system. And the power flow transmission function in such a system as with multi disturbance, multi mounts, passive isolators and actuators is deduced. By means of the numerical simulation method, the influence of actuators on power flow transmission characteristic is studied. And as a conclusion, the passive active synthetic control strategy of power flow is summarized.

关键词： Vibration isolation Power flow Coupling Active control

Early Cambrian Ichnofossils from the Mussoorie Syncline and revision of Trace Fossil Biozonation of the Lesser Himalaya, India

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Acta Geologica Sinica(English Edition) 2014年第2期88卷 380-393页

作者： Birendra P. Singh Kapesa Lokho naval Kishore Nancy Virmani Center of Advanced Study in Geology Panjab University Wadia Institute of Himalayan Geology

A new locality bearing ichnofossils of the Cruziana Assemblage Zone-Ⅲ from the Mussoorie syncline,Lesser Himalaya,is located in rocks of Member-B of the Dhaulagiri Formation,Tal Group,exposed along the Maldewta-Chhimoli fresh road cut *** site yielded ichnofossils Bergaueria perata,Cochlichnus anguineus,？Diplocraterion isp.,Dimorphichnus obliquus,diplichnitiform Cruziana bonariensis,Diplichnites gouldi,Glockeria isp.,Helminthopsis isp.,Monomorphichnus lineatus,Phycodes palmatum,Palaeophycus striatus,Planolites beverleyensis,Planolites montanus,Treptichnus ***,scratch marks and an undetermined worm *** Early Cambrian age （Cambrian Series 2） is assigned to the ichnofossil-bearing strata based on the stratigraphic position between the Drepanuroides and Palaeoolenus trilobite zones.A revised Cambrian ichnofossil zonation is presented for the Tal Group of the Mussoorie *** with their occurrence on rippled surfaces,and the lateral displacement of some trackways （due to current action）,a sub-aqueous shallow-marine depositional setting is proposed for the rocks of Member-B.

关键词： Ichnology Cruziana Assemblage Zone Cambrian Series 2 shallow-marine northern India

PREDICTION OF PODDED PROPELLER CAVITATION USING AN UNSTEADY SURFACE PANEL METHOD

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Journal of Hydrodynamics 2008年第6期20卷 790-796页

作者： YE Jin-ming XIONG Ying College of naval Architecture and Power Naval University of Engineering Wuhan 430033 China

The unsteady sheet cavitation of podded propeller was predicted by using a surface panel method. The interaction between propeller and pod was treated with the iterative calculation of induced velocity potential, and the method of induced velocity potential can save a great deal of storage and computation time compared to the method of induced velocity. The induced velocity potential of unit singularity on every pod panel to every key blade panel and of unit singularity on every key blade panel and its wake panel to every pod panel were calculated when the key blade is at every angle position. Based on the wake model of the conventional single propeller, a new wake model of podded propeller was constructed. The propeller is analyzed only on the key blade in order to save computation time and memory space. The method can be used to calculate the hydrodynamics performance and cavitation of propeller in uniform and non-uniform inflows. It can give the unsteady force and cavitation shape of propeller. The propeller cavitation range determined by the present method agrees with the observation results of cavity image given in cavitation tunnel well, and this proves the practicability of the method.

关键词： pod propeller unsteady performance cavitation surface panel method

Synergistic extraction and separation of Am(III) and Ln(III) with HBMPPT-sulfoxide-HNO_3-toluene system

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Nuclear Science and Techniques 2000年第3期11卷 192-196页

作者： YU Shao-Ning naval Medical Research Institute, Shanghai 200433 解放军海军医学所上海 200423

Some sulfoxides (petroleum sulfoxide - PSO, di-n-octyl sulfoxide - DOSO, etc.) were chosen as synergists to study the synergistic effect on the extraction reaction with HBMPPT (4-benzoy1-2,4-dihydro-5-menthy1-2-pheny1-3H-pyrazol1-3-thione) for Am(III), and the synergistic separation for Am(III) and Ln(III). The synergistic extraction ability of PSO is greater than that of DOSO for Am(III). The synergistic complexes may be presented as ***3.(BMPPT)***.S2 (S indicates PSO or DOSO).

关键词：镅(Ⅲ) 镧子元素 HBMPPT 萃取体系萃取剂核燃料增效作用分离硝酸亚砜甲苯

NUMERICAL SIMULATION OF WAVE RESISTANCE OF TRIMARANS BY NONLINEAR WAVE MAKING THEORY WITH SINKING AND TRIM BEING TAKEN INTO ACCOUNT

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Journal of Hydrodynamics 2011年第2期23卷 224-233页

作者： WANG Zhong LU Xiao-ping College of naval Architecture and Power Naval University of Engineering Wuhan 430033 China

Up to now, there are no satisfactory numerical methods for simulating wave resistance of trimarans, mainly due to the difficulty related with the strong nonlinear features of the piece hull wave making and their interference. This article proposes a numerical method for quick and effective calculation of wave resistance of trimarans to be used in engineering applications. Based on Wyatt＇s work, the nonlinear free surface boundary condition, the time domain concept, and the full nonlinear wave making theory, using the Rankine source Green function, the 3-D surface panel method is expanded to solve the trimaran wave making problems, with high order nonlinear factors being taken into account, such as the influence of the sinking and trim, transom, and ship wave immersed hull surface. And the software is successfully developed to implement the method, which is validated. Several trimaran models, including a practical trimaran with a sonar dome and the transom, are used as numerical calculation samples, their wave making resistance is calculated both by the present method and some other methods such as linear （Dawson） methods. Moreover, sample model resistance tests were carried out to provide data for comparison, validation and analysis. Through the validation by model experiments, it is concluded that present method can well predict the wave making resistance, sinking and trim, and the accuracy of wave making resistance calculation is significantly improved by taking the trim and sinking into account, especially at high speeds.

关键词： trimaran nonlinear wave making resistance surface panel method sinking trim ship model test

Influence of Interpenetrating Polymer Networks (IPN) Microstructure on Underwater Acoustic Stealth Performance

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Journal of Wuhan University of Technology(Materials Science) 2010年第2期25卷 272-277页

作者：罗忠 College of naval Architecture and Power Naval University of Engineering

According to the configuration and absorption theory of polymer macromolecule materials, a kind of IPN with wider temperature range and higher damping property was designed and synthesized. By using the spectrum of dynamic mechanical thermal analysis （DMTA） and acoustic pulse tube device, the microstructure, phase separation degree, phase size and phase continuity of IPN with different components were analyzed. The experimental results show that the nano size grade of phase, the continuous and homogeneous IPN phase can provide higher absorption coefficient. The absorption coefficient of optimized sample I09 is 0.7 in 2 kHz, and the absorption peak is 0.9 in 4 kHz. Then the underwater acoustic properties of modified IPN filled with mica, micro-balloon and nano-SiO2 were discussed respectively to indicate that the inhomogeneous property of filler-modified IPN can improve the underwater acoustic stealth performance effectively, and the micro size grade of these filler-modified IPN can work well in low frequency acoustic stealth.

关键词： interpenetrating polymer networks (IPN) polyurethane damping absorption coefficient fillers

FLOW NOISE MEASUREMENT OF SURFACE SHIP WITH TOWED MODEL

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Journal of Hydrodynamics 2008年第6期20卷 784-789页

作者： GAO Xiao-peng BI Yi MIAO Guo-ping School of naval Architecture Ocean and Civil Engineering Shanghai Jiao Tong University Shanghai 200030 China College of naval Architecture and Power Naval University of Engineering Wuhan 430033 China

In this article, a new acoustic test technique using towed model was introduced to study flow noise caused by a surface ship. The project of model test was be properly designed for acoustic signal collecting and with the help of appropriate data processing method different kinds of acoustic sources could be successfully identified. A lot of work about fuid noise could be carried on with the towed model, and the noise corresponding to low frequency which is especially interested for its long distance radiating with small attenuation could also be studied in this way.

关键词： acoustic test surface ship towed model flow noise short-time Fourier transform