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Couple stress fluid flow in a rotating channel with peristalsis

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Journal of Hydrodynamics 2018年第2期30卷 307-316页

作者： Y.Abd elmaboud sara I.Abdelsalam Kh.s.Mekheimer Mathematics Department Faculty of Science and Arts Khulais University Of Jeddah Mathematics Department Faculty of Science Al-Azhar University (Assiut Branch) Department of Mechanical Engineering University of CaliforniaRiverside USA Basic science Department Faculty of Engineering The British University in Egypt Mathematics Department Faculty of Science Al-Azhar University

This article describes a new model for obtaining closed-form semi-analytical solutions of peristaltic flow induced by sinusoidal wave trains propagating with constant speed on the walls of a two-dimensional rotating infinite channel. The channel rotates with a constant angular speed about the z-axis and is filled with couple stress fluid. The governing equations of the channel deformation and the flow rate inside the channel are derived using the lubrication theory approach. The resulting equations are solved, using the homotopy perturbation method（HPM）, for exact solutions to the longitudinal velocity distribution, pressure gradient, flow rate due to secondary velocity, and pressure rise per wavelength. The effect of various values of physical parameters, such as, Taylor＇s number and couple stress parameter, together with some interesting features of peristaltic flow are discussed through graphs. The trapping phenomenon is investigated for different values of parameters under consideration. It is shown that Taylor＇s number and the couple stress parameter have an increasing effect on the longitudinal velocity distribution till half of the channel, on the flow rate due to secondary velocity, and on the number of closed streamlines circulating the bolus.

关键词： Homotopy perturbation method (HPM) couple stress fluid rotating channel peristaltic transport

Graphite-like and Diamond-like Carbon Coatings with Exceptional Tribological Properties

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材料热处理学报 2004年第05B期25卷 796-802页

作者： M. Jarratt s. K. Field D.G. Teer Teer Coatings Ltd. West Stone House West Stone Berry Hill Industrial Estate Droitwich WR9 9AS UKTeer Coatings Ltd. West Stone House West Stone Berry Hill Industrial Estate Droitwich WR9 9AS UKTeer Coatings Ltd. West Stone House West Stone Berry Hill Industrial Estate Droitwich WR9 9AS UK

Two hard, carbon-based solid lubricant coatings, Graphit-iC? and Dymon-iC?, have been developed that offer considerable benefits for industry. Both of these new coatings have a high tribological load-bearing capacity, exceptional wear resistance and very low friction, even in dry or lubricant-starved contact. This is in contrast to many commercial diamond-like carbon, DLC coatings, which tend to be highly stressed and therefore brittle, making them unsuitable for high load bearing industrial applications. The development of the new solid lubricant coatings is described, and details of their tribological performance in dry, water and oil-lubricated environments are given. The structure of the coatings has been investigated and related to the tribological properties, and the mechanism for the low friction and wear rates is discussed. The coatings have been used to successfully improve the lifetime and efficiency of many highly loaded mechanical parts, including automotive fuel injection components, gears, bearings, tappets (cam followers), gudgeon (wrist) pins, etc. They also offer benefits for tooling and are widely used in forming or machining of non-ferrous alloys, and extensively on dies and moulds. Other industrial application areas include electrical devices that require either high conductivity or insulation, optical devices requiring abrasion resistance and surgical tools and implants.

关键词： DLC 摩擦力碳覆层固体润滑剂

A Comparison of Carlin-type Gold Deposits：Guizhou Province,Golden Triangle,southwest China,and Northern Nevada,UsA

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地学前缘 2013年第1期20卷 1-18页

作者： Jean s.CLlNE John L.MUNTEAN Xuexiang GU Yong XIA University of Nevada Las Vegas Nevada BareaH of Mines and Geology and University of Nevada Reno school of Earth sciences and Resources China University of Geosiences(Beijing) state Key Laboratory of Ore Deposit Geochemistry.Institute of Geochemistry.Chinese Academy of sciemces

several Au deposits in Guizhou Province,southwest China,described as being similar to the highly productive Carlin-type gold deposits in northern ***,were examined to identify similarities and differences between the two *** were collected along transects from lowto high-grade rock,where possible,and fram stockpiles at the shuiyindong,Zimudang,Taipingdong,Yata and Jinfeng(formerly Lannigou)*** used to examine ore and alteration minerals included hand-sample description:reflectance spectroscopy using an AsD Terraspec spectrometer;analyses of hand samples by carbonate staining with Alizaren red and potassium ferricyanide;transmitted and reflected light petrography;chemical analyses,mineral identification,and imaging using a ***-5610 scanning electron microscope:and quantitative chemical analyses using a JEOL JXA-8900 electron probe *** analyses of hand samples for 52 elements were done by ALs *** indicate both similarities and differences between the two *** districts have similar geologic *** deposits at both locations appear to have formed as a result of similar tectonic *** the district in southwest China lacks evidence of eoeval felsic igneous activity;however,the ore-stage minerals and the fluids that produced the minerals and deposits have some significant *** Nevada deposits were dominated by fluid-rock reaction in which host rock Fe was sulfidized to form Au-bearing *** ore fluids sulfidized host rock Fe in the Cuizhou *** timing of Fe metasomatism is unknown,so whether the deposits formed in response to sulfidation or pyritization is ***-rock reaction between an acidic,aqueous fluid and highly reactive calcareous rocks in Nevada caused extensive decarbonatization of host rocks,jasperoid replacemerit of carbonate minerals,and alteration of silty rock components to illite and *** Guizhou,CO2-bearing ore flu

关键词：地质地理学地质构造气藏

Information Transmission in Phase synchronous Chaotic Arrays

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Chinese Physics Letters 2006年第3期23卷 560-563页

作者： M. s. Baptista C. Zhou J. Kurths Universitat Potsdam Institut for Physik Am Neuen Palais 10 D-14469 Potsdam Deutschland

We show many versatile phase synchronous configurations that emerge in an array of coupled chaotic elements due to the presence of a periodic stimulus. Then, we explain the relevance of these configurations to the understanding of how information about such a stimulus is transmitted from one side to the other in this array. The stimulus actively creates the ways to be transmitted, by making the chaotic elements to phase synchronize.

关键词： NEURAL sPIKE TRAINs sYNCHRONIZATION

Vibration suppression in multi-tool ultrasonic machining to multi-external and parametric excitations

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Acta Mechanica sinica 2009年第3期25卷 403-415页

作者： M.M.Kamel W.A.A.El-Ganaini Y.s.Hamed Department of Engineering Mathematics Faculty of Electronic EngineeringMenoufiya University

Ultrasonic machining （UsM） is of particular interest for the machining of non-conductive, brittle materials such as engineering ceramics. In this paper, a multi-tool technique is used in UsM to reduce the vibration in the tool holder and have reasonable amplitude for the tools. This can be done via dynamic absorbers. The coupling of four nonlinear oscillators of the tool holder and tools representing ultrasonic cutting process are investigated. This leads to a four-degree-of-freedom system subjected to multi-external and multi-parametric excitation forces. The aim of this work is to control the tool holder behavior at simultaneous primary, sub-harmonic and internal resonance condition. Multiple scale perturbation method is used to obtain the solution up to the second order approximations. The different resonance cases are reported and studied numerically. The stability of the system is investigated by using both phase-plane and frequency response techniques. The effects of the different parameters of the tools on the system behavior are studied numerically. Comparison with the available published work is reported.

关键词： Control stability Ultrasonic machining (UsM)

Effect of Anions on Toxicity of Cadmium Applied to Microbial Biomass in Red soil

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Pedosphere 1997年第3期7卷 231-235页

作者： K．s．KHAN XIEZHENGMIAO 等 CollegeofNaturalResourcesandEnvironmentalscience ZhejiangAgriculturalUniversityHangzhou310029（China）

A laboratory incubation experiment was conducted to elucidate the effects of associated anions on toxicity of cadmium applied to microbial biomass in the red soil. Cadmium was applied at six different levels, i.e., 0 (background), 5, 15, 30, 60 and 100 μg-1 soil in the form of either cadmium acetate or cadmium *** of cadmium as cadmium acetate markedly reduced the soil microbial biomass carbon compared to cadmium applied as cadmium chloride at all the tested levels. similarly, organic carbon to biomass carbon ratio in the soil was markedly increased by increasing the level of the cadmium in the soil as cadmium acetate,while the change was much smaller in the case of cadmium chloride at the same cadmium levels. The results suggested that due consideration should be given to the source of cadmium while deciding the cadmium levels in experiments.

关键词： anions cadmium toxicity microbial biomass red soil

δ-WAVE FOR 1-D AND 2-D HYPERBOLIC sYsTEMs

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Journal of Computational Mathematics 1996年第3期14卷 256-262页

作者： s.L. Yang(Institute of Applied Mathematics, Chinese Academy of sciences, Beijing, China) CHINEsE ACAD sCI INST APPL MATHBEIJINGPEOPLES R CHINA

Here a new kind of nonlinear wave, which is called δ-wave, is described by some high resolution difference solutions for Riemann problems of one-dimensional (1-D) and two-dimensional (2-D) nonlinear hyperbolic systems in conservation laws. some phenomena are numerically shown for the solutions of Riemann problems for 2-D gas dynamics systems

关键词： Zhang WAVE FOR 1-D AND 2-D HYPERBOLIC sYsTEMs

Lattice Boltzmann method and RANs approach for simulation of turbulent flows and particle transport and deposition

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Particuology 2017年第1期15卷 62-72页

作者： H. sajjadi M. salmanzadeh G. Ahmadi s. Jafari Department of Mechanical Engineering Shahid Bahonar University ofKerman Kerrnan lran Department of Mechanical and Aeronautical Engineering Clarkson University Potsdam NY USA Department of Petroleum Engineering Shahid Bahonar University ofKerrnan Kerman lran

Using the lattice-Boltzmann computational approach in conjunction with the Reynolds averaged Navier-stokes （RANs） model, several turbulent flows and the transport and deposition of particles in different passages were studied. The new lattice Boltzmann method （LBM） solved the RANs equations coupled with the standard and renormalization group k-E turbulence models. In particular, the LBM formulation was augmented by the addition of two transport equations for the probability distribution function of populations of k and 8. The discrete random walk model was used to generate the instanta- neous turbulence fluctuations. For turbulent channel flows, the analytical fits to the root mean-square velocity fluctuations obtained by the direct numerical simulation of the turbulent flow were used in the analysis. Attention was given to the proper evaluation of the wall normal turbulent velocity fluctuations particularly near the wall. The simulation results were compared with the available numerical simulation and experimental data. The new LBM-RANs model is shown to provide a reasonably accurate description of turbulent flows and particle transport and deposition at modest computational cost.

关键词： Lattice Boltzmann method Reynolds averaged Navier-stokes Renormalization group model k-ε model Particle transport and deposition

Multiple Antibiotic Resistance and Heavy Metal Resistance Profile of Bacteria Isolated from Giant Freshwater Prawn (Macrobrachium rosenbergii) Hatchery

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Agricultural sciences in China 2009年第6期8卷 740-745页

作者： s W Lee M Najiah W Wendy A Zahrol M Nadirah Department of Fishery and Aquaculture Faculty of Agrotechnology and Food Science Universiti Malaysia Terengganu

In this article, antibiogram and heavy metal resistance profile of bacteria isolated from giant freshwater prawn （Macrobrachium rosenbergii） hatchery in Malaysia are described. Although giant freshwater prawn was introduced into Malaysia since the 1980s, there was no database information on antibiogram and heavy metal resistance profile of bacteria from giant freshwater prawn （34. rosenbergii） hatchery in Malaysia. Therefore, this study was carried out to determine the effectiveness of antibiotic and heavy metal resistance profile to control bacterial diseases in M. rosenbergii hatchery. The results can provide valuable information for local M. rosenbergii post-larval producer. Antibiotic sensitivity test was carried out by disk-diffusion method against 15 types of antibiotics as follows： oxolinic acid （2 μg）, ampicillin （10μg）, erythromycin （15μg）, furazolidone （15 μg）, lincomycin （15μg）, amoxicillin （25 μg）, colistin sulphate （25 μg）, doxycycline （30μg）, florfenicol （30 μg）, flumequine （30 lag）, nalidixic acid （30μg）, tetracycline （30μg）, oleandomycin （15μg）, fosfomycin （50μg）, and spiramycin （100 μg）, whereas heavy metal resistance profile of the present bacterial isolates was determined by 2-fold agar dilution technique. In this study, 5 types of bacteria were successfully isolated; they were Aeromonas spp. （n = 77）, Escherichia coli （n = 73）, Edwardsiella spp. （n = 62）, salmonella spp. （n = 75）, and Vibrio spp. （n = 43）. The result showed that furazolidone was the most effective antibiotic to control the bacteria isolated in this study, approximately 89.7% of the bacterial isolates were sensitive to this antibiotic. Multiple antibiotic resistance （MAR） index indicated that the hatchery water source and M. rosenbergii post-larval and sediment tanks were at high-risk exposure to the tested antibiotic. Furthermore, all the tested heavy metals （Cd2＋, Cr6＋, Hg2＋, and Cu2＋） failed to inhibit the growth of the bacterial isolates. Therefore, it indicated that the water

关键词： Macrobrachium rosenbergii hatchery antibiotic heavy metal MAR index