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Mineralogy and Geochemistry of Major, Trace and Rare Earth Elements in Sediments of the Hypersaline Urmia Salt Lake, Iran

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Acta Geologica Sinica(English Edition) 2018年第4期92卷 1384-1395页

作者： samad ALIPOUR Khadije MOSAVI ONLAGHI Geology Department Faculty of Sciences UrmiaUniversity Urmia Iran Urmia University Urmia Iran

Urmia Salt Lake （USL） is a hypersaline lake located at the NW corner of the Iran platform. The lake area is estimated to have been over 5000 km2 at one point, but has now decreased to 〈1000 km^2 in the last two decades. It contains 4.6×109 tons of halite and other detrital and evaporative minerals such as calcite, aragonite, dolomite, quartz, feldspars, augite and sylvite. This study examined the mineralogy and geochemistry of bed sediments along the mid-east toward NE bank sediments collected from 1.5 meters depth and nearby augite placer. Due to the diverse iithology of the surrounding geology, bed sediments vary from felsic in the mid-east to mafic in the northeast. Weathering of tephrite and adakite rocks of the Islamic Island at the immediate boundary has produced a large volume of augite placer over a 40 km length, parallel to the shoreline. Based on the study result, weathering increases from south to north and the geochemistry of the sediments shows enrichment of MgO, CaO, Sr and Ba associated with Sr deployment in all samples. Rare earth elements （REE） patterns normalized to the upper continental crust （UCC） indicated LREEs enrichment compared to HREEs with an elevated anomaly of Eu, possibly due to surface absorbance of Mn and Fe minerals, associated with Sr elevation originating from adakites in the lake basin vicinity.

关键词： mineralogy geochemistry augite placer Urmia Lake Iran

A perspective on 3D bioprinting in tissue regeneration

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Bio-Design and Manufacturing 2018年第3期1卷 157-160页

作者： samad Ahadian Ali Khademhosseini Department of Bioengineering University of California Los Angeles CA 90095-1600 USA Center for Minimally Invasive Therapeutics (C-MIT) University of California Los Angeles CA 90095-1600 USA California NanoSystems Institute (CNSI) University of California Los Angeles CA 90095-1600 USA Department of Radiological Sciences University of California Los Angeles CA 90095-1600 USA Department of Chemical and Biomolecular Engineering University of California Los Angeles CA 90095-1600 USA

IntroductionA rapidly increasing need for organ transplantation and short list of donated organs have led to the development of new materials and technologies for organ manufacturing. Although some simple organs, such as skin and cartilage, have been successfully fabricated and commercialized, it is still difficult to make tissues and organs with high complexity. Engineered tissues have other biomedical applications, such as drug screening models and bio-actuators. Threedimensional （3D） bioprinting has become a great tool to fabricate tissue constructs on demand for transplantation and other biomedical applications.

关键词：器官移植生物材料生物技术发展现状

Studies on batch adsorptive removal of cadmium and nickel from synthetic waste water using silty clay originated from Balochistan-Pakistan

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Chinese Journal of Chemical Engineering 2020年第4期28卷 1171-1176页

作者： Abdul samad Muhammad Imran Din Mahmood Ahmed Institute of Chemistry University of the PunjabLahore 54590Pakistan Renacon Pharma Limited Lahore 54600Pakistan

The potentials of silty clay(SC),acquired from Chaman,Balochistan,were investigated as adsorbent for Ni(Ⅱ)and Cd(Ⅱ)removal from contaminated *** influence of different operating factors like dose,pH,temperature,and time of contact was explored,and optimum values were noted under batch adsorption *** study was conducted with varying concentrations of solutions on optimized conditions and different adsorption models i.e.,Langmuir,Freundlich,Temkin and Dubinin-Radushkevich(D-R)isotherm,which were employed to interpret the *** isothermal data of both Ni(Ⅱ)and Cd(Ⅱ)were well fitted to Langmuir isotherm suggesting the formation of monolayer of metal ions on silty *** values of adsorption capacity noted for Ni(Ⅱ)and Cd(Ⅱ)were 3.603 mg·g^-1 and 5.480 mg·g^-1,*** studies affirmed that pseudo second order(PSO)kinetics was being obeyed by the removal of Ni(Ⅱ)and Cd(Ⅱ).Thermodynamic variables like free energy change(ΔG°),enthalpy change(ΔH°)and entropy change(ΔS°)were *** negative value ofΔG°and the positive values ofΔH°andΔS°unfolded that the removal process of both metal ions of by SC was spontaneous,endothermic and feasible.

关键词： Adsorption Kinetics Isotherm Toxicity Silty clay Thermodynamics

Smart scaffolds in tissue regeneration

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Regenerative Biomaterials 2018年第3期5卷 125-128页

作者： samad Ahadian Ali Khademhosseini Toronto General Research Institute University Health NetworkTorontoON M5G 2C4Canada Department of Bioengineering Department of Radiology Department of Chemical and Biomolecular Engineering Center for Minimally Invasive Therapeutics(C-MIT) California NanoSystems Institute(CNSI) University of CaliforniaLos AngelesCA 90095-1600USA

Recent advances in biofabrication technologies and chemical synthesis approaches have enabled the fabrication of smart scaffolds that aim to mimic the dynamic nature of the native extracellular *** scaffolds have pave... 详细信息

关键词： drug delivery scaffolds regenerative mechanism

Analysis and Modeling of Propagation in Tunnel at 3.7 and 28 GHz

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Computers, Materials & Continua 2022年第5期71卷 3127-3143页

作者： Md Abdus samad Dong-You Choi Department of Information and Communication Engineering Chosun UniversityGwangju61452Korea Department of Electronics and Telecommunication Engineering International Islamic University ChittagongChittagong4318Bangladesh

In present-day society,train tunnels are extensively used as a means of ***,to ensure safety,streamlined train operations,and uninterrupted internet access inside train tunnels,reliable wave propagation modeling is *** have experimented and measured wave propagation models in a 1674 m long straight train tunnel in South *** measured path loss and the received signal strength were modeled with the Close-In(CI),Floating intercept(FI),CI model with a frequency-weighted path loss exponent(CIF),and alpha-beta-gamma(ABG)models,where the model parameters were determined using minimum mean square error(MMSE)*** measured and the CI,FI,CIF,and ABG modelderived path loss was plotted in graphs,and the model closest to the measured path loss was identified through *** on the measured results,it was observed that every model had a comparatively lower(n<2)path loss exponent(PLE)inside the *** also determined the path loss component’s possible deviation(shadow factor)through a Gaussian distribution considering zero mean and standard deviation calculations of random error *** FI model outperformed all the examined models as it yielded a path loss closer to the measured datasets,as well as a minimum standard deviation of the shadow factor.

关键词： Path loss shadow factor telecommunications train tunnel wave propagation wireless networks

Synthesis of zinc oxide nanoparticles reinforced clay and their applications for removal of Pb(II)ions from aqueous media

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Chinese Journal of Chemical Engineering 2021年第4期34卷 454-461页

作者： Abdul samad Muhammad Imran Din Mahmood Ahmed Saghir Ahmad Institute of Chemistry University of the PunjabLahore 54590Pakistan Renacon Pharma Limited Lahore 54600Pakistan

The aim of the study was to synthesize zinc oxide nanoparticles(ZnONPs)composite with clay by a novel route and then to explore the capability of composite of ZnONPs and silty clay(SC)as adsorbents for Pb(II)eradication from aqueous media by batch adsorption *** effect of different operating factors like temperature,pH,dose and time of contact on the adsorption process were studied to optimize the ***,Freundlich,Dubinin-Radushkevich(DR)and Temkin isotherms were applied for the interpretation of the *** R^(2)and q values obtained from Langmuir model suggested that the process is best interpreted by this *** values of adsorption capacity(qm)noted were 12.43 mg·g^(-1) and 14.54 mg·g^(-1)on SC and ZnONPsSC *** kinetic studies exposed that pseudo second order(PSO)kinetics is followed by the processes suggesting that more than one steps are involved to control the rate of *** thermodynamic variables such as change in free energy(AGe),change in enthalpy(AH9)and change in entropy(ASe)were *** data suggested that Pb(II)adsorption on SC and ZnONPsSC are spontaneous,endothermic and feasible processes.

关键词： Adsorption Isotherm Kinetics Silty clay Thermodynamic

Time-delay effect and design of closed-loop control system of circulation control airfoil

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Chinese Journal of Aeronautics 2024年第10期37卷 50-67页

作者： Lingxiao Li Heyong XU Zheng XING Abdul samad KHAN School of Aeronautics Northwestern Polytechnical UniversityXi’an 710072China National Key Laboratory of Aircraft Configuration Design Xi’an 710072China

In this paper,unsteady numerical simulation of jet Circulation Control(CC)is carried out with the NACA0012-CC airfoil as the research *** dynamic process from the opening of jet slot and adjustment of jet intensity to the stable state of jet control effect is *** time-delay effect and flow mechanism of jet are *** mechanism of jet momentum coefficient and moment coefficient fluctuating with time is *** fluctuation of jet momentum coefficient is caused by the change of the pressure coefficient distribution on the Coanda surface or the structure of the wave system inside the jet,and the oscillation frequency of the wave system structure of the under-expansion supersonic jet reaches 1481 Hz at the opening *** on the aerodynamic model and Proportional-Integral-Derivative(PID)control theory,the closed-loop control system of CC airfoil is *** parameters of PID control system are adjusted by the Genetic Algorithm(GA),which significantly improves the response ability of the control system to step,ramp and sine signals,and improves the dynamic performance of the *** at the special time-delay effect of jet control,Long Short-Term Memory(LSTM)neural network module is added to the control system to predict the target input signal,which strengthens the prediction ability of GA-PID control system to the target signal at the next time *** using LSTM neural network correction,the control hysteresis caused by jet time-delay effect is alleviated,and the response ability of the control system is effectively ***,the designed LSTM-GA-PID control system is applied to the NACA0012-CC airfoil for the pitch control simulation *** test results show that the control system designed in this paper has good dynamic performance and can respond quickly and accurately to complex input signals,which confirms the effectiveness of the control system.

关键词： Circulation control Unsteady numerical simulation Time-delay effect Control system Long short-term memory

Efficient video-on-demand services over mobile datacast channels

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2006年第5期7卷 873-884页

作者： JENKA Hrvoje STOCKHAMMER Thomas ABDEL samad Wissam Institute for Communications Engineering Munich University of Technology Munich 80333 Germany Nomor Research Bergen 83346 Germany BenQ Mobile Munich 81675 Germany

The integration of reliable Video-on-Demand (VoD) broadcasting schemes in the DVB-h transmission system is studied, exemplary for Pyramid Broadcasting (PB). Sophisticated VoD broadcasting schemes such as PB allow receivers to tune into the ongoing transmission of a video-stream at arbitrary time, while still being able to receive the multimedia sequence from the beginning to end, after a short initial playout latency. Raptor coding, integrated in the FLUTE protocol, is combined with the traditional PB scheme in order to provide high service and presentation reliability. We give a short overview on the DVB-h transmission system as well as on the FLUTE protocol. We present and discuss options for the integration of VoD broadcasting schemes in combination with Raptor coding. We achieve backward-compatibility even with terminals not supporting Raptor coding. Simulation results show the benefits of the discussed VoD scheme compared to existing carousel approaches in DVB-h.

关键词： Video-on-Demand (VoD) DVB-h Pyramid broadcasting FLUTE protocol Raptor code

Comparison of Artificial Neural Networks,Geographically Weighted Regression and Cokriging Methods for Predicting the Spatial Distribution of Soil Macronutrients(N,P,and K)

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Chinese Geographical Science 2017年第5期27卷 747-759页

作者： samad EMAMGHOLIZADEH Shahin SHAHSAVANI Mohamad Amin ESLAMI 1.Department of Water and Soil Engineering Shahrood University of TechnologyShahrood361999-5161Iran

Soil macronutrients(i.e. nitrogen(N), phosphorus(P), and potassium(K)) are important soils components and knowing the spatial distribution of these parameters are necessary at precision agriculture. The purpose of this study was to evaluate the feasibility of different methods such as artificial neural networks(ANN) and two geostatistical methods(geographically weighted regression(GWR) and cokriging(CK)) to estimate N, P and K contents. For this purpose, soil samples were taken from topsoil(0–30 cm) at 106 points and analyzed for their chemical and physical parameters. These data were divided into calibration(n = 84) and validation(n = 22). Chemical and physical variables including clay, p H and organic carbon(OC) were used as auxiliary soil variables to estimate the N, P and K contents. Results showed that the ANN model(with coefficient of determination R^2 = 0.922 and root mean square error RMSE = 0.0079%) was more accurate compared to the CK model(with R^2 = 0.612 and RMSE = 0.0094%), and the GWR model(with R^2 = 0.872 and RMSE = 0.0089%) to estimate the N variable. The ANN model estimated the P with the RMSE of 3.630 ppm, which was respectively 28.93% and 20.00% less than the RMSE of 4.680 ppm and 4.357 ppm from the CK and GWR models. The estimated K by CK, GWR and ANN models have the RMSE of 76.794 ppm, 75.790 ppm and 52.484 ppm. Results indicated that the performance of the CK model for estimation of macro nutrients(N, P and K) was slightly lower than the GWR model. Also, the accuracy of the ANN model was higher than CK and GWR models, which proved to be more effective and reliable methods for estimating macro nutrients.

关键词： precision agriculture soil characteristics interpolation artificial neural networks geographically weighted regression Cokriging