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Multidimensional modeling of the effect of fuel injection pressure on temperature distribution in cylinder of a turbocharged DI diesel engine

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Propulsion and Power Research 2013年第2期2卷 162-175页

作者： Sajjad Emami samad Jafarmadar Young Researchers and Elie Club Khoy BranchIslamic Azad UniversityKhoyWest Azerbaijian 58159-15149Iran Mechanical Engineering Department Technical Education FacultyUmia UniversityUmiaWest Azerbaijan 57561-15311Iran

In this study,maintaining a constant fuel rate,injection pressure of 275 bar to1000 bar(275 × 10^(2) kPa to 1000× 10^(2) kPa),has been *** of injection pressure,the pressure inside the cylinder on the free energy,power,engine indicators,particularlyindicators of fuel consumption,pollutants and their effects on parameters affecting the outputof the engine combustion chamber have been studied in droplet ***,the effects offuel mixture equivalence,Cantor temperature,soot and NO_(x),due to the increase of injectionpressure,engine efficiency and emissions have been examined.

关键词： Injection pressure Indicated power Temperature contour Equivalence contour Soot NO_(x) Combustion modeling

A highly efficient procedure for the synthesis of quinoxaline derivatives using polyvinylpolypyrrolidone supported triflic acid catalyst(***)

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Chinese Chemical Letters 2014年第9期25卷 1287-1290页

作者： samad Khaksar Mahmoud Tajbakhsh Milad Gholami Fariba Rostamnezhad Chemistry Department Islamic Azad UniversityAyatollah Amoli Branch Department of Organic Chemistry Faculty of ChemistryUniversity of Mazandaran

A polyvinylpolypyrrolidone supported triflic acid was shown to be useful as a recyclable heterogeneous catalyst for the rapid and efficient synthesis of quinoxaline derivatives in good-to-excellent yields. The catalys... 详细信息

关键词： Quinoxaline Reusable Heterocyclic Heterogeneous

Comprehensive toxicity assessment of nanodiamond on Blaps polychresta: implications and novel findings

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Insect Science 2024年第6期31卷 1838-1863页

作者： Marwa Saad Nabila Selim Lamia M.El-samad Faculty of Science Department of ZoologyAlexandria UniversityAlexandriaEgypt

With the increasing development of nanomaterials,the use of nanodiamonds(NDs)has been broadly manifested in many ***,their high penetration into the ecosystem indubitably poses remarkable toxicological *** paper investigates the toxic effects of NDs on the darkling beetle,Blaps polychresta Forskal,1775(Coleoptera:Tenebrionidae).Survival analysis was carried out by monitoring the beetles for 30 d after the injection of four different doses of NDs.A dose of 10.0 mg NDs/g body weight,causing less than 50%mortality effect,was assigned in the analysis of the different organs of studied beetles,including testis,ovary,and *** and ultrastructural analyses were followed using light,TEM,and SEM *** addition,a variety of stress markers and enzyme activities were assessed using spectrophotometric ***,cell viability and DNA damage were evaluated using cytometry and comet assay,*** to the control group,the NDs-treated group was exposed to various abnormalities within all the studied organs as *** disturbances in enzyme activities were accompanied by an apparent dysregulation in the antioxidant *** flow cytometry results indicated a substantial decrease of viable cells along with a rise of apoptotic and necrotic *** comet assay demonstrated a highly increased level of DNA ***,histological analyses accentuated the same findings showing remarkable deformities in the studied ***,the research findings substantially contribute for the first time to evaluating the critical effects of NDs on ***,adopted as the bioindicator in this paper.

关键词： Blaps polychresta ecotoxicity molecular analysis nanodiamond oxidative stress pathophysiology

Pericyst: The outermost layer of hydatid cyst

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World Journal of Gastroenterology 2014年第5期20卷 1377-1378页

作者： samad EJ Golzari Mohsen Sokouti Cardiovascular Research Center Tabriz University of Medical Sciences Department of Cardiothoracic Surgery Tabriz University of Medical Sciences

Hydatid disease,caused by the parasite Echinococcus granulosus,mostly affects the liver and the lungs with hydatid cysts which consist of three layers:(1)the outer pericyst;(2)the middle laminated membrane;and(3)the inner germinal ***,as the outermost layer of the hydatid cyst,is made by host cells encasing the hydatid *** extremely close interaction exists between this host tissue and the parasite,and any degenerative changes of the pericyst would result in hydatid cyst degeneration or *** pericyst plays an undeniably important role in the development and survival of the hydatid cyst.

关键词： Hydatid disease Echinococcus granulosus Hydatid cyst Pericyst Layer

Supramolecular synthesis of 3,4-dihydropyrimidine-2(1H)-one/thiones under neat conditions

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Chinese Chemical Letters 2011年第2期22卷 127-130页

作者： Sekineh Asghari Mahmood Tajbakhsh Behnam Jafarzadeh Kenari samad Khaksar Department of Chemistry University of MazandaranBabolsarIran Chemistry Department Islamic Azad UniversityAyatollah Amoli BranchAmolIran

An efficient solvent free method for the synthesis of various 3,4-dihydropyrimidin-2（1H）-one/thiones in excellent yields using sulfonatedβ-cyclodextrine as recyclable catalyst is ***β-cyclodextrine was found to be efficient,recyclable heterogeneous catalyst and showed rate enhancements,high yields and short reaction times in this transformation.

关键词： Cyclodextrine Recyclable catalyst Heterogeneous Dihydropyrimidine

Performance Analysis of Spatially Correlated Massive MIMO with Hardware Impairments

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Performance Analysis of Spatially Correlated Massive MIMO wi...

作者： Zeeshan samad 上海交通大学

学位级别：硕士

Multiple-input multiple-output(MIMO) system with very large number of base station(BS)antennas has attained a lot of attention in recent years. Since, it improves the overall system capacity as well as Bit Error Rate(BER) by exploiting the advantages of high degrees of freedom and better spatial multiplexing. Performance analysis described in this thesis mainly concern with two serious *** Impairments: Implementation of large number of antennas on a BS expected to have low power consumption and low-budget radio frequency(RF) components which are prone to hardware impairments. Phase noise(PN), high power amplifier(HPA) nonlinearities, or in phase/quadrature-phase(I/Q) imbalance) are some reasons of introduction such impairments that can drastically effect the performance of large scale MIMO *** mitigation schemes are used to overcome the impact of hardware impairments but unfortunately, these schemes are not perfect enough such that a certain amount of residual RF hardware impairment always *** Correlations: Deployment of large number of antennas on both the transmit and the receive side introduces cross correlations between multiple transmission *** reason of such correlations is the narrow space between adjacent antenna elements. It is essential to consider such correlations during analyzing the system *** the design of practical cellular systems, the actual benefit of multi-antenna transmission is limited by a variety of factors such as hardware impairments and the correlation between multiple transmission channels. In this thesis, we design a new system model for MIMO system by taking transmit RF impairments into account and consider it as an additional distortion during transmission. We further define a spatially correlated channel model to investigate the impact of channel correlations on system capacity. Next a general capacity expression is derived to analyze the performance of massive MIMO in various

关键词： s-MIMO correlated channels channel capacity transmit-RF impairment

Effect of Fluidic Diode on Performance of Unidirectional Impulse Turbine

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Journal of Thermal Science 2024年第3期33卷 807-814页

作者： DODDAMANI Hithaish ABDUS samad MANABU Takao SHINYA Okuhara M M ASHRAFUL Alam Department of Ocean Engineering Indian Institute of Technology MadrasChennai600036India Department of Mechanical Engineering National Institute of TechnologyMatsue CollegeShimane6908518Japan Center of Support Practical Education National Institute of TechnologyMatsue CollegeShimane6908518Japan Department of Transportation Engineering Osaka Sangyo UniversityDaito5748530Japan

A pair of unidirectional turbines(UT)can operate in oscillatory airflow without additional ***,this arrangement suffers from poor flow rectification.A fluidic diode(FD)offers variable hydrodynamic resistance based on the flow direction,and this can be coupled with UT to improve flow *** this work,a numerical investigation on the effect of FD with UT is presented using the commercial fluid dynamics software ANSYS Fluent 16.1 with k-ωSST turbulence closure *** domains of UT and FD are numerically validated individually with experimental ***,both are coupled to obtain the combined effect,and these results are compared with the analytical *** was observed that coupling FD with UT improved the unit's performance at the lower flow coefficient(<1),but its performance decreased as the flow coefficient *** to the diode's presence,fluid leaving the turbine experiences higher resistance at a higher flow coefficient,which decreases the overall performance of the combined unit.

关键词： wave energy oscillating water column unidirectional impulse turbine fluidic diode flow rectification

Effects of polyurethane hardness on the propagation of acoustic signals from partial discharge

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High Voltage 2024年第5期9卷 1125-1135页

作者： Abdul samad W.H.Siew Martin Given John Liggat Igor Timoshkin Department of Electronic and Electrical Engineering University of StrathclydeGlasgowUK Department of Pure and Applied Chemistry University of StrathclydeGlasgowUK

Polymeric insulation is a critical component of high voltage ***,exposure to high electric stress can cause partial discharges(PDs)to occur and may result in the deterioration of insulation and lead to dielectric *** PD events are accompanied by the production of acoustic pressure impulses in the *** of these acoustic pressure impulses can reveal the presence of PDs and locate their ***,analysing the detected acoustic emission(AE)signal is *** acoustic pressure source's nature and the propagating medium's properties,such as density,viscosity,and elasticity,significantly affect the propagating AE *** effects of the hardness of the polyurethane(PU)on the propagating AE signal are reported by the authors based on results obtained from laboratory *** was observed that the decay rate in the magnitude of the acoustic impulse was high in PU at all hardness levels following an exponential *** analysis of the frequency spectra indicates that the higher frequency components attenuate more strongly with *** laboratory results can be valuable for engineers and industries as they provide valuable insight into how the physical characteristics of a material affect the propagation characteristics of AE signals during the detection and location of PD source using the AE detection technique.

关键词： polyurethane insulation propagation

Assessment of Indoor and Outdoor Radon Levels in South Lebanon

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International Journal of Disaster Risk Science 2014年第3期5卷 214-226页

作者： Mohammed A.Kobeissi Omar El samad Khaled Zahraman Ibrahim Rachidi Lebanese Atomic Energy Commission National Council for Scientific ResearchRiad ElsolhBeirutLebanon Department of Physics Faculty of Sciences(I)The Lebanese UniversityHadethBeirutLebanon

The presence of high indoor radon concentrations,Cx,is a major concern of the public *** of indoor radon in South Lebanon have been achieved using CR-39 *** ranged between 30 and 122 Bq m-3 in one of the major towns in the area and are compared with measured atmospheric air *** seasonal variation of Cxindoors has been observed,although 90%of the obtained indoor Cxmeasurements are below 100 Bq *** homes produced Cxreadings above the permissible *** showed that the ventilation effect played a major factor in reducing radon concentration levels *** assessment has been *** effective doses of radon varied from 1.01±0.10 to 8.65±0.50 m Sv a-1 in six homes in one of the four cases *** dosage values are above the permitted limit of 2.5 m Sv *** types of granite contained in the studied homes were identified and their contributions to radon levels indoors were calculated.

关键词： Building materials CR-39 Effective dose Granite exhalation rate Lebanon Radon risk assessment