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Chemical Research in Chinese Universities 2014年第1期30卷 68-74页

作者： AI-Bogami Abdullah saad Department of Chemistry Faculty of Science King Abdulaziz University North Jeddah Jeddah 21589 Saudi Arabia

We reported the environmental benign synthesis of chalcones,2-pyrazolines and cyclohexanones under microwave *** were obtained by the condensation of each of 2-hydroxyacetophenone derivatives with a-naphthaldehyde under microwave *** condensation reactions of each of synthesized chalcones with phenyl hydrazine under microwave irradiation in the presence of dry acetic acid as a cyclizing agent gave ***,the new cyclohexenone derivatives,valuable intermediates to synthesize fused heterocycles,have been prepared by the cyclocondensation of each of hydroxychalcones with ethyl *** structures of the synthesized compounds were elucidated by infrared（IR） spectrometry,nuclear magnetic resonance（NMR）,mass spectrometry（MS） and elmental *** results indicate that unlike classical heating,microwave irradiation results in higher yields with shorter and cleaner *** synthesized compounds were screened for antimicrobial activity against Staphylococcus aureus,Escherichia coli,Candida Albicans and Aspergillus *** clarified the effects of different substituents in the tested compounds on the obtaind antibacterial activities and antifungal activities.

关键词： Microwave irradiation 2-Hydroxyacetophenone α-Naphthaldehyde Pyrazoline Cyclohexenone Antimicrobial activity

A Novel Design of an Aquatic Walking Robot Having Webbed Feet

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International Journal of Automation and computing 2017年第5期14卷 576-588页

作者： saad Kashem Hutomo Sufyan Swinburne University of Technology Sarawak CampusJalan Simpang Tiga 93350KuchingSarawakMalaysia

Inspired by the movement of duck that is able to move on land and water utilizing its webbed feet, a novel design of an amphibious robot has been presented in this paper. In contrary, the orthodox design of amphibious robot utilizes the tracks or wheels on land and switches to the propeller to move in water. The proposed design employs same propulsion system as webbed feet to move on land and water. After studying the movement of the duck underwater, a conclusion has been drawn that it is swimming in the water by moving its webbed feet back and forth to generate force to push its body forward. Recreating this phenomenon of duck movement, hybrid robot locomotion has been designed and developed which is able to walk, swim and climb steps using the same propulsion system. Moreover, webbed feet would be able to walk efficiently on muddy, icy or sandy terrain due to uneven distribution of robot weight on the feet. To be able to justify the feasibility of the design, simulations are being carried out using SimulationXpress of the SOLIDWORKS software.

关键词： Amphibious robot webbed feet duck feet robot locomotion swim walk climb propulsion system.

Analytical fits to the synchrotron functions

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Research in Astronomy and Astrophysics 2013年第6期13卷 680-686页

作者： Mourad Fouka saad Ouichaoui Research Center in Astronomy Astrophysics and GeophysicsB. P. 63 Algiers ObservatoryBouzaréah Algiers Algeria Université des Sciences et de la Technologie Houari Boumediène (USTHB) Faculté dePhysique Laboratoire SNIRMB.P. 32 El-Alia 16111 Bab Ezzouar Algiers Algeria

Accurate fitting formulae to the synchrotron function, F（x）, and its com- plementary function, G（x）, are performed and presented. The corresponding relative errors are less than 0.26% and 0.035% for F（x） and G（x）, respectively. To this end we have, first, fitted the modified Bessel functions, Ks/3（x） and K2/3（x）. For all the fitted functions, the general fit expression is the same, and is based on the well known asymptotic forms for low and large values of z for each function. It consists of multi- plying each asymptotic form by a function that tends to unity or zero for low and large values of z. Simple formulae are suggested in this paper, depending on adjustable parameters. The latter have been determined by adopting the Levenberg-Marquardt algorithm. The proposed formulae should be of great utility and simplicity for com- puting spectral powers and the degree of polarization for synchrotron radiation, both for laboratory and astrophysical applications.

关键词： radiation processes: non thermal -- methods: analytical

不同有机肥替代20%化肥氮的稻田土壤有机氮组分积累特征

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湖南农业科学 2024年第8期 29-35页

作者：刘华彭复细陈俊林娇周玉安 Nader saad 张振华夏银行湖南省慈利县农业农村局湖南慈利427200 湖南农业大学资源学院湖南长沙410128 岳麓山实验室湖南长沙410128

为了探明不同有机肥等比例替代化肥下土壤有机氮各组分积累特征,依托长期施肥定位试验,以不施氮肥(CK)和施用化肥氮(NPK)为对照,检测分析了猪粪(PM)、商品有机肥(OM)和早稻紫云英+晚稻水稻秸秆(RMS)替代20%化肥氮处理下土壤有机氮组分... 详细信息

为了探明不同有机肥等比例替代化肥下土壤有机氮各组分积累特征,依托长期施肥定位试验,以不施氮肥(CK)和施用化肥氮(NPK)为对照,检测分析了猪粪(PM)、商品有机肥(OM)和早稻紫云英+晚稻水稻秸秆(RMS)替代20%化肥氮处理下土壤有机氮组分含量及其占全氮的比例。结果表明:全氮和有机氮组分含量在NPK和CK处理之间差异不明显;与NPK处理相比,有机肥替代化肥各处理的土壤全氮含量提高了5.2%~8.5%,尤其是PM处理;且3种有机肥替代化肥的酸解氨基酸氮、酸解铵态氮和酸解氨基糖氮的含量分别显著提高了11.0%~18.8%、10.8%~18.5%和16.7%~31.1%,其占全氮比例分别提高了4.4%~11.1%、2.1%~12.6%和7.5%~24.5%,增加了土壤速效氮含量,尤其是RMS处理;其原因可能是有机肥替代化肥不同程度地增加了微生物生物量碳氮,增强了氮转化相关酶活性,促进了难分解有机氮组分向易分解有机氮组分的转化。综上,有机肥等比例替代化肥均能有效提高土壤氮素积累和供应,其中猪粪更有利于氮素积累,秸秆更有利于增强氮素供应潜力。

关键词：等比例替代有机氮组分微生物生物量酶活性稻田土壤

Comparison of different energy saving lights using solar pa.el

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Frontiers in Energy 2016年第4期10卷 466-472页

作者： Huzaifa MUBARAK saad Bin Abul KASHEM Sarawak Campus Swinbume University of Technology Kuching93350 Malaysia

The recent trend in light emitting diode or LED lighting applications and their claimed energy saving capabilities together with their overall attractiveness has us all convinced that they really are a greener alternative to the compact fluorescent lights or CFL. As convincing as it seems, the actual energy saving capabilities of LEDs are yet to be proven scientifically or at the least, on an empirical level when compared to CFLs. This paper tackles the issue with the use of a solar cell by evaluating the photovoltaic current and voltage generated by the solar cell subjected to each lighting system. Graphical representations are drawn and a conclusion is then reached based on the amount of power generation in the solar cells in order to determine the energy saving capabilities of each lighting system and its efficiency. From the result, it has been found that an LED is 3.7 times more power efficient than a CFL based light source of equal wattage.

关键词： CFL LED empirical solar lumens energysaving fluorescent

Homogeneous Finite-Time Consensus Control for Higher-Order Multi-Agent Systems by Full Order Sliding Mode

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Journal of Systems Science & Complexity 2018年第5期31卷 1186-1205页

作者： MONDAL Sanjoy GHOMMAM Jawhar saad Maarouf School of electrical and electronic Engineering Nanyang Technological University Department of electrical Engineering Ecole de technologie superieure

This paper investigates the distributed finite-time consensus tracking problem for higher- order nonlinear multi-agent systems （MASs）. The distributed finite-time consensus protocol is based on full order sliding surface and super twisting algorithm. The nominal consensus control for the MASs is designed based on the geometric homogeneous finite time control technique. The chattering is avoided by designing a full order sliding surface. The switching control is constructed by integrating super twisting algorithm, hence a chattering alleviation protocol is obtained to maintain a smooth control input. The finite time convergence analysis for the leader follower network is presented by using strict Lyapunov function. Finally, the numerical simulations validate the proposed homogeneous full-order sliding mode control for higher-order MASs.

关键词： Finite time control full order sliding mode multi agent systems.

Spinal dural arteriovenous fistula:a comprehensive review of the history,classification systems,management,and prognosis

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Chinese Neurosurgical Journal 2024年第1期10卷 48-56页

作者： Ali Alkhaibary Ahoud Alharbi Nada Alnefaie Hajar Alammar Alshaymaa M.Arishy Noor Alghanim Yazeed M.Aldhfyan Arwa Albaiahy Yahya H.Khormi Wael Alshaya saad AlQahatani Ahmed Aloraidi Ahmed Alkhani Sami Khairy College of Medicine King Saud Bin Abdulaziz University for Health SciencesRiyadhSaudi Arabia King Abdullah International Medical Research Center RiyadhSaudi Arabia Division of Neurosurgery Department of SurgeryKing Abdulaziz Medical CityMinistry of National Guard-Health AffairsRiyadhSaudi Arabia Department of Neurosurgery National Neurosciences InstituteKing Fahad Medical CityRiyadhSaudi Arabia College of Medicine Jazan UniversityJazanSaudi Arabia Department of Neurosurgery King Faisal Specialist Hospital and Research CenterRiyadhSaudi Arabia Department of Surgery Faculty of MedicineJazan UniversityJazanSaudi Arabia

Spinal dural arteriovenous fistulas account for the majority of spinal vascular *** are typically located in the thoracolumbar region and are diagnosed in the middle-aged and elderly *** spinal dural arteriovenous fistulas have been postulated to be acquired,their exact development remains ***,the arteriovenous shunt is situated close to the spinal nerve root,inside the dura mater,where the blood from the radiculomeningeal artery and radicular vein *** history,there have been multiple classification systems of spinal arteriovenous shunts since *** were mainly based on the evolution of diagnostic studies as well as the treatment of these *** classification systems have undergone significant changes over the *** intracranial dural arteriovenous fistula,spinal dural arteriovenous fistula is progressive in *** neurological manifestations,due to venous congestion,tend to be insidious as well as *** include sensory deficits,such as paresthesia,bilateral and/or unilateral radicular pain affecting the lower limbs,and gait *** dural arteriovenous fistulas can be suspected on magnetic resonance imaging/magnetic resonance angiography and confirmed by digital subtraction angiography(DSA).The management includes surgery,endovascular therapy,and in selected cases,*** treatment goal of spinal dural arteriovenous fistula is to halt the progression of the *** prognosis depends on both the duration of symptoms as well as the clinical condition prior to *** present article comprehensively reviews the pathophysiology,changes in classification systems,natural history,clinical manifestations,radiological features,management,and prognosis.

关键词： Connection Endovascular Myelopathy Vascular

A simulation of doping and trap effects on the spectral response of AlGaN ultraviolet detectors

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Journal of Semiconductors 2012年第3期33卷 20-23页

作者： Sidi Ould saad Hamady LMOPS University Paul Verlaine-Metz and SUPELEC-2 Rue Edouard Belin57070 MetzFrance

We study,by means of numerical simulation,the impact of doping and traps on the performance of the＂solar blind＂ultraviolet Schottky detector based on *** implemented physical models and AlGaN material properties taken from the literature,or from the interpolation between the binary materials（GaN and AlN） weighted by the mole *** found that doping and traps highly impact the spectral response of the device,and in particular a compromise in the doping concentration must be reached in order to optimize the spectral response of the *** results give us a powerful tool to quantitatively understand the impact of elaboration and processing conditions on photodetector characteristics,and thus identify the key issues for the development of the technology.

关键词： simulation AlGaN ultraviolet detector spectral response

Characterization of 3D microstructure,thermal conductivity,and heat flow of cement-based foam using imaging technique

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Frontiers of Structural and Civil Engineering 2021年第3期15卷 643-651页

作者： Farnaz BATOOL Muhammad saad KHAN Vivek BINDIGANAVILE Department of Civil Engineering NED University of Engineering&TechnologyKarachi75270Pakistan Department of Civil and Environmental Engineering University of AlbertaEdmontonT6G2R3Canada

This study presents the results of the 3D microstructure,thermal conductivity,and heat flow in cement-based foams and examines their changes with a range of *** were captured using X-ray micro computed tomography(micro-CT)imaging technique on cement-based foam samples prepared with densities of 400,600,and 800 kg/m^(3).These images were later simulated and quantified using 3D data visualization and analysis *** on the analysis,the pore volume of 11000µm^(3)was determined across the three densities,leading to optimal ***,distinct pore diameters of 15µm for 800 kg/m^(3),and 20µm for 600 and 400 kg/m^(3)were found to be *** of the pores were spherical,with only 10%appearing elongated or *** addition,a difference of 15%was observed between the 2D and 3D porosity ***,a difference of 5%was noticed between the experimentally measured thermal conductivity and the numerically predicted value and this variation was constant across the three cast *** 3D model showed that heat flows through the cement paste solids and with an increase in porosity this flow reduces.

关键词： 3D pore volume distribution X-ray tomography 3D shape factor heat flow

The potency of N,N′-diphenyl-1,4-phenylenediamine and adiposederived stem cell co-administration in alleviating hepatorenal dysfunction complications associated with type 1 diabetes mellitus in rats

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BIOCelL 2023年第8期47卷 1885-1895页

作者： HANY M.ABD el-LATEEF SAFA H.QAHL EMAN FAYAD SARAH A.ALTALHI IBRAHIM JAFRI el SHAIMAA SHABANA MARWA K.DARWISH REHAB MAHER saad SHAABAN SHADY G.el-SAWAH Department of Chemistry College of ScienceKing Faisal UniversityAl-AhsaSaudi Arabia Chemistry Department Faculty of ScienceSohag UniversitySohagEgypt Department of Biology College of ScienceUniversity of JeddahJeddahSaudi Arabia Department of Biotechnology College of ScienceTaif UniversityTaifSaudi Arabia Fellow of Biochemistry Genetic UnitChildren HospitalFaculty of MedicineMansoura UniversityMansouraEgypt Chemistry Department(Biochemistry Branch) Faculty of ScienceSuez UniversitySuezEgypt Department of Clinical Laboratories Sciences College of Applied Medical SciencesShaqra UniversityRiyadhSaudi Arabia Biology Department Faculty of ScienceMansoura UniversityMansouraEgypt Department of Chemistry Organic Chemistry DivisionCollege of ScienceMansoura UniversityMansouraEgypt Zoology Department Faculty of ScienceArish UniversityNorth SinaiEgypt

Background:The increasing occurrence of diabetes mellitus(DM)noted worldwide has considerably elicited concern in the recent *** is associated with elevated vascular complications,morbidity,mortality,and poor quality of *** this context,mesenchymal stem cells(MSCs)have shown significant therapeutic potentialities in managing and curing type 1 DM owing to their self-renewable,immunosuppressive,and differentiation *** investigated the potential action of N,N′-diphenyl-1,4-phenylenediamine(DPPD),a well-known synthetic antioxidant to enhance the therapeutic ability of the adipose-derived stem cells(AD-MSCs)in alleviating kidney and liver complications in diabetic ***:Over the four weeks of experiments,albino male rats(n=36)were split into six test groups:control,DPPD(250 mg/kg,i.p.),STZ-diabetic(D),D+DPPD,D+AD-MSCs(1×10^(6)cell/rat,i.v.),and D+AD-MSCs+DPPD treated ***:Significant declines in the renal and hepatic oxidative stress markers(MDA,ROS,and AGEs)were observed coupled with a significant elevation in many antioxidant marker levels(GSH,SOD,CAT,GPx,HO-1,and TAC)in the diabetic rats treated with either DPPD or AD-MSCs or their co-administered injection compared to the diabetic untreated *** was suggested to be the leading cause of a.elioration of the kidney functions(as measured by urea,uric acid,and creatine levels)and liver functions(as evidenced by the levels of AST,ALT,ALP,bilirubin,total proteins,albumin,and globulins).Conclusion:DPPD and AD-MSCs co-administration showed superior results in terms of the enhancement of the relative hepato-renal function,indicating the beneficial role of DPPD supplementation in increasing the therapeutic potential of AD-MSCs.

关键词： Antioxidants Diabetic nephropathy DPPD Oxidative stress Stem cells