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Weathering and accumulation of trace elements in the soils of the Porali Plain, Balochistan: repercussions in agriculture

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Acta Geochimica 2024年第2期43卷 214-234页

作者： Maria Kaleem Erum Bashir Shahid Naseem Tahir Rafique Bushra shahab Department of Geology University of KarachiKarachi 75270Pakistan Applied Chemistry Research Centre PCSIR Laboratories ComplexKarachi 75280Pakistan

This study is theﬁrst attempt to assess the nature of the soil,especially on the western side of the Porali Plain in Balochistan;a new emerging agriculture hub,using weathering and pollution indices supplemented by multi-variate analysis based on geochemical *** outcomes of this study are expected to help farmers in soil manage-ment and selecting suitable crops for the ***-ﬁve soil samples were collected,mainly from the arable land of the Porali *** drying and coning-quarter-ing,soil samples were analyzed for major and trace ele-ments using the XRF technique;sieving and hydrometric methods were employed for granulometric ***-mated data were analyzed using Excel,SPSS,and Surfer software to calculate various indices,correlation matrix,and spatial *** granulometric analysis showed that 76%of the samples belonged to loam types of soil,12%to sand type,and 8%to silt *** indices:CIA,CIW,PIA,PWI,WIP,CIX,and ICV were calculated to infer the level of *** indices reﬂect mod-erate to intense weathering;supported by K_(2)O/AI_(2)O_(3),Rb/K_(2)O,Rb/Ti,and Rb/Sr *** of the geo-ac-cumulation and Nemerow Pollution indices pinpoint rela-tively high concentrations of Pb,Ni,and Cr concentration in the *** correlation matrix and Principal Compo-nent Analysis show that the soil in this study area is mainly derived from the weathering of igneous rocks of Bela Ophiolite(Cretaceous age)and Jurassic sedimentary rocks of Mor Range having SEDEX/MVT type *** may result in the undesirable accumulation of certain trace elements which adversely affects crops.

关键词： Weathering indices Pollution indices Accumulation Repercussions Trace elements Multivariate analyses Porali Plain Balochistan

Improving Linked-Lists Using Tree Search Algorithms for Neighbor Finding in Variable-Resolution Smoothed Particle Hydrodynamics

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Communications in Computational Physics 2019年第6期26卷 57-86页

作者： shahab Khorasanizade J.M.M.Sousa IDMEC Instituto Superior T́ecnicoUniversidade de LisboaAv.Rovisco Pais1049-001 LisboaPortugal

Improving linked-lists for neighbor finding with the use of tree search algorithms is proposed here,aiming to cope with highly non-uniform resolution simulations employing a meshless *** new procedure,coined Quadtree Cells Grid,has been implemented in Smoothed Particle Hydrodynamics(SPH).The SPH scheme employed is adaptive,thus allowing for particle refinement in desired regions of the *** to the wide range of coexisting particle mass levels,standard linked-list neighbor search algorithms become ***,an alternative is found based on the use of hierarchical data structures,using quadtrees(in 2D problems).The present algorithm exploits the advantages of both linked-lists and quadtree meth-ods with the goal of increasing computational efficiency,when dealing with highly non-uniform particle *** cases involving two distinct flow problems have demonstrated that the computational cost of the current adaptive neighbor finding algorithm scales linearly with the total number of particles,thus retrieving this characteristic of linkedlists in uniform grid ***,the memory usage increased as a result of the more complex data structure.

关键词： Smoothed particle hydrodynamics linked-list quadtree neighbor finding variable resolution

Evolution of biomass particles during pelletization process

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Particuology 2024年第3期86卷 182-187页

作者： Hamid Rezaei Maryam Tajilrou Jun Sian Lee Kanages Singaraveloo Anthony Lau shahab Sokhansanj Biomass and Bioenergy Research Group Department of Chemical and Biological EngineeringUniversity of British ColumbiaVancouverCanada

Pulverizing is an essential unit operation in co-firing biomass with *** are only compatible with pellet forms of fibrous biomass materials and crush them down to their original forming particle *** is why the data on the size distribution of the particles forming a biomass pellet is crucial to achieving optimum combustion *** current study determines the internal particle size distribution of pellets after wet disintegration,following Iso 17830 standard,and aims to suggest improvements to the mentioned standard based on new measured *** were carried out on white wood pellets(no bark)and brown wood pellets containing bark at four water temperatures:20,40,60,and 95℃,with or without *** particle size distribution of the pre-pelletizer wood particles was also measured and compared with particles in the formed *** water temperature of 20℃ was found to be adequate for the complete disintegration of pellets,and no mechanical stirring was *** 30% of particles in the disintegrated pellets were 0.5-1.0 *** changes the particle size distribution to smaller *** disintegrated bark pellets contained more fines than white pellets.

关键词： Wood pellets Particle sizes distribution Wet disintegration Stirring Water temperature

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智能代理在油藏建模中的应用

石油勘探与开发 2020年第2期47卷 372-382页

作者： SHAHKARAMI Alireza MOHAGHEGH shahab 圣费朗西斯大学美国俄克拉荷马73104 西费吉尼亚大学美国西费吉尼亚州摩根敦26506

利用人工智能和机器学习技术,采用人工神经网络开发并验证了用于油藏模拟历史拟合、敏感性分析和不确定性评估的智能代理模型,将其应用于油藏模拟的两个案例中。第1个案例研究了代理模型在油藏模型历史拟合中的应用,输出结果预测了井的... 详细信息

利用人工智能和机器学习技术,采用人工神经网络开发并验证了用于油藏模拟历史拟合、敏感性分析和不确定性评估的智能代理模型,将其应用于油藏模拟的两个案例中。第1个案例研究了代理模型在油藏模型历史拟合中的应用,输出结果预测了井的产量;第2个案例研究了基于人工神经网络的代理模型在CO2提高采收率油藏快速建模中的应用,目标为预测油藏压力和相饱和度在注入期间以及注入后的分布,预测效果均良好。相比基础数值模拟模型,智能代理模型运行单次模拟只需几秒钟,总节省98.9%的运算时间。智能代理模型在运算速度、消耗时间以及成本等方面都有巨大的优势。此外,智能代理模型与基础油藏模型模拟结果非常接近。

关键词：智能代理建模油藏模拟机器学习人工神经网络历史拟合敏感性分析优化技术 CO2驱提高采收率

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Transforming Hand Drawn Wireframes into Front-End Code with Deep Learning

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Computers, Materials & Continua 2022年第9期72卷 4303-4321页

作者： Saman Riaz Ali Arshad shahab S.Band Amir Mosavi Department of Computer Science National University of TechnologyIslamabad44000Pakistan Department of Computer Science Institute of Space TechnologyIslamabad44000Pakistan Future Technology Research Center National Yunlin University of Science and TechnologyDouliu64002YunlinTaiwan Faculty of Civil Engineering Technische Universitat DresdenDresden 01069Germany

The way towards generating a website front end involves a designersettling on an idea for what kind of layout they want the website to have, thenproceeding to plan and implement each aspect one by one until they haveconverted what they initially laid out into its Html front end form, this processcan take a considerable time, especially considering the first draft of the designis traditionally never the final one. This process can take up a large amountof resource real estate, and as we have laid out in this paper, by using a Modelconsisting of various Neural Networks trained on a custom dataset. It can beautomated into assisting designers, allowing them to focus on the other morecomplicated parts of the system they are designing by quickly generating whatwould rather be straightforward busywork. Over the past 20 years, the boomin how much the internet is used and the sheer volume of pages on it demands ahigh level of work and time to create them. For the efficiency of the process, weproposed a multi-model-based architecture on image captioning, consisting ofConvolutional neural network (CNN) and Long short-term memory (LSTM)models. Our proposed approach trained on our custom-made database can beautomated into assisting designers, allowing them to focus on the other morecomplicated part of the system. We trained our model in several batches overa custom-made dataset consisting of over 6300 files and were finally able toachieve a Bilingual Evaluation Understudy (BLEU) score for a batch of 50hand-drawn images at 87.86%.

关键词： Deep learning wireframes front-end low fidelity high fidelity design process html computer vision dsl

DFT Study of Physisorption Effect of the Curcumin on CNT(8,0-6) Nanotube for Biological Applications

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Chinese Journal of Structural Chemistry 2019年第1期38卷 37-52,2页

作者： SIYAMAK shahab MASOOME Sheikhi MEHRNOOSH Khaleghian IRYNA Balakhanava FATEMEH Azarakhshi Institute of Physical Organic Chemistry National Academy of Sciences of Belarus Institute of Chemistry of New Materials National Academy of Sciences of Belarus Belarussian State University Young Researchers and Elite Club Gorgan Branch Islamic Azad University Department of Chemistry Islamshahr Branch Islamic Azad University Department of Chemistry Varamin-Pishva Branch Islamic Azad University

In the given work the adsorption properties of molecule curcumin((1 E,6 E)-1,7-bis(4-hydroxy-3-methoxyphenyl)-1,6-heptadiene-3,5-dione) on CNT(8,0-6) nanotube were investigated by the density functional theory(DFT) in the solvent water for the first time. The non-bonded interaction effects of compounds curcumin and CNT(8,0-6) nanotube on the electronic properties, UV/Vis spectra, chemical shift tensors and natural charges were determined and discussed. The electronic spectra of the compound curcumin and the complex CNT(8,0-6)/curcumin in the solvent water were calculated by time dependent density functional theory(TD-DFT) for investigation of the maximum wavelength value of molecule Curcumin before and after the non-bonded interaction with the CNT(8,0-6) nanotube and molecular orbitals involved in the formation of absorption spectrum of the complex CNT(8,0-6)/curcumin at maximum wavelength.

关键词： CNT(8,0-6)nanotube Curcumin DFT interaction physisorption

Fe_3O_4@MCM-48-OSO_3H磁性核壳纳米粒子催化3,3′-双吲哚高效合成(英文)

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催化学报 2015年第5期36卷 778-784页

作者： Alireza Khorshidi shahab Shariati Department of Chemistry Faculty of Sciences University of Guilan Department of Chemistry Rasht Branch Islamic Azad University

Magnetite nanoparticles coated with sulfuric acid-functionalized mesoporous MCM-48 were synthesized and used as a catalyst in three-component domino reactions of indoles, arylglyoxal monohydrates and N-arylenaminones to furnish the desired 3,3′-bisindoles by formation of two C–C and one C–N bonds in a smooth cascade with good yields under mild reaction conditions. The catalyst was recovered easily and maintained activity in successive runs.

关键词：纳米粒子 Fe304 催化合成核壳磁性 MCM-48 反应条件运行维护

Synthesis of cobalt, palladium, and rhenium nanoparticles

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Tungsten 2020年第3期2卷 261-288页

作者： shahab Ranjbar Bahadori Ryan Hart Yao‑Wu Hao Department of Materials Science and Engineering University of Texas at ArlingtonArlingtonTX 76019USA

Over the past decade,metal nanoparticles(MNPs)have attracted extensive attention due to their unique physiochemical properties that make them highly applicable in various fields such as chemical sensing,energy storage,catalysis,medicine,and environmental *** physiochemical properties depend drastically on the MNP size and morphology,which are largely determined by their synthesis *** on MNPs predominantly focused on coinage metals(Au,Ag and Cu),but in the last decade research on metals with a relatively high melting temperature such as Pd,Co,and Re has seen rapid increases,mainly driven by their potential applications as *** paper presents the recent advances on different synthesis techniques of Co,Pd,and Re nanoparticles,their resulting nanostructures,as well as existing and potential applications.

关键词： Nanotechnology Co nanoparticle Pd nanoparticle Re nanoparticle Nanoparticle synthesis

Heat transfer in a tapered fluidized bed of biomass particles with pulsed gas flow

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Particuology 2019年第1期17卷 2-14页

作者： Dening Jia Xiaotao Bi C. Jim Lim shahab Sokhansanj Atsushi Tsutsumi Department of Chemical and Biological Engineering The University of British Columbia2360 East MallVancouverBCV6T 1Z3Canada Environmental Sciences Division Oak Ridge National LaboratoryOak RidgeTN 37831USA Collaborative Research Center for Energy Engineering Institute of Industrial ScienceThe University of Tokyo4-6-1 KomabaMeguro-kuTokyo 153-8505Japan

Bed-to-surface heat transfer of pure biomass particles in a pulsed fluidized bed with a tapered bottom section was investigated. Three biomass species — Douglas fir, pine, and switchgrass — were studied under various operating conditions. Their heat transfer coefficients were found to be closely associated with hydrodynamics dominated by gas pulsations. A higher superficial gas velocity generally yielded better gas–solid contact and higher heat transfer rates. A moderately increasing pulsation frequency promoted convective heat transfer of particles but also reduced pulsation intensity, leading to undesired flow behaviours such as channelling and partial defluidization. The study of the pulsation duty cycle revealed that, for cohesive particles, a smaller duty cycle was preferred to generate powerful pulsations to break up inter-particle forces. Moreover, a duty cycle increase allowed higher gas throughput as long as a suitable fluidization was maintained. The addition of finer particles to a coarse fraction increased particle mobility, and subsequently heat transfer, which also explained the higher heat transfer coefficients of switchgrass as it contained more fines compared with fir and pine. Experimental results in the tapered bed were also compared with those of non-tapered geometry where a 10%–20% increase in heat transfer was observed.

关键词： Fluidized bed Gas pulsations Tapered column Heat transfer Biomass