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Influence of alumina on mineralogy and environmental properties of zinc-copper smelting slags

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International Journal of Minerals,Metallurgy and Materials 2013年第3期20卷 234-245页

作者： sina Mostaghel Caisa Samuelsson Bo Bjrkman Minerals and Metals Research Laboratory Lule University of Technology

An iron-silicate slag, from a zinc-copper smelting process, and mixtures of this slag with 5wt%, 10wt%, and 15wt% alumina addition were re-melted, semi-rapidly solidified, and characterized using scanning electron microscopy equipped with energy dispersive spectroscopy, and X-ray diffraction. The FactSageWM6.2 thermodynamic package was applied to compare the stable phases at equilibrium conditions with experimental characterization. A standard European leaching test was also carried out for all samples to investigate the changes in leaching behaviour because of the addition of alumina. Results show that the commonly reported phases for slags from copper and zinc production processes （olivine, pyroxene, and spinel） are the major constituents of the current samples. A correlation can be seen between mineralogical characteristics and leaching behaviours. The sample with 10wt% alumina addition, which contains high amounts of spinels and lower amounts of the other soluble phases, shows the lowest leachabilities for most of the elements.

关键词： slags characterization mineralogy alumina leaching solidification

Pore volumes to breakthrough estimation in carbonate acidizing with hydrochloric acid by using an analytical derivation method

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Petroleum 2020年第4期6卷 362-367页

作者： sina Lohrasb Radzuan Junin Department of Petroleum Engineering School of Chemical and Energy EngineeringUniversiti Teknologi MalaysiaUTMSkudai81310JohorMalaysia Institute for Oil and Gas Universiti Teknologi Malaysia81310JohorMalaysia

Acidizing treatment is considered as a significant process in the oil well stimulations to form wormholes in carbonate formation in order to enhance the reservoir fluid *** the number of pore volumes to breakthrough is an important objective in matrix acidizing,for it contributes to determining the wormhole characteristics such as type,shape,and *** this number in experimental works requires a considerable amount of time,energy and ***,this study aimed to establish an analytical method in which a reasonable result is achieved for the number of pore volumes to *** purpose is accomplished by solely implementing acid and formation properties without performing any experimental *** process of wormhole creation is done through developing a numerical model by utilizing the conservation of mass law method in which the carbonate core is considered as a closed system and the overall mass in the system as constant during the acid injection ***,a constant number is added to the mathematical part of the model in order to eliminate the dimensionless Damk鰄ler number which is supposed to be calculated *** results of the numerical procedure of the model are further compared to four other experimental works,which led to calculating the average accuracy of this model that is shown to be 95.98%.This study puts forward a comprehensive numerical model to estimate the number of pore volumes to breakthrough with an acceptable accuracy rate merely through implementing known acid and core properties.

关键词： Analytical method Carbonate acidizing Pore volume to breakthrough Hydrochloric acid

Conventional *** pseudo-dynamic seismic analyses in the shallow strip footing bearing capacity problem

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Earthquake Engineering and Engineering Vibration 2021年第4期20卷 993-1006页

作者： Ghazal Rezaie Soufi Reza Jamshidi Chenari sina Javankhoshdel Department of Civil Engineering Faculty of EngineeringUniversity of GuilanP.O.3756RashtGuilanIran Rocscience Inc. 54 Saint Patrick St.Toronto M5T 1V1OntarioCanada

The conventional pseudo-dynamic(CPD)and modified pseudo-dynamic(MPD)methods are invoked to obtain the seismic bearing capacity of strip foundations using the limit equilibrium method,with a two-wedge failure mechanism.A spectral version of the conventional pseudo-dynamic method(SPD)is also invoked by considering the ground motion amplification factor,to be a function of the non-dimensional frequencyλ/B and soil *** analyses show that bearing capacity results obtained by the MPD and SPD methods are generally *** experience the same general reduction in bearing capacity with the increase ofλ/B,with successive ups and downs corresponding to soil′s natural *** 5<λ/B<10,SPD and MPD results fluctuated between falling above and below CPD ***λ/B<2.5,SPD and MPD results were consistent with attenuation of the shear wave,while for 10<λ/B,amplification was *** obtained by the CPD method monotonically decrease,due to the fact that CPD fails to inherently consider site effects and damping,and instead and relies on a single factor to consider the ground motion amplification.

关键词： bearing capacity modified pseudo-dynamic method conventional pseudo-dynamic method spectral analysis

Spatial separation effects in a guiding procedure in a modified ion-beam-sputtering process

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Light(Science & Applications) 2015年第1期4卷 109-116页

作者： sina Malobabic Marco Jupé Detlev Ristau Laser Zentrum Hannover e.V. Hollerithallee 8D-30419 HannoverGermany QUEST:Centre for Quantum Engineering and Space-Time Research Leibniz Universität HannoverHannoverGermany

In the present state of the art,ion beam sputtering is used to produce low-loss dielectric *** the manufacturing of a dielectric layer stack,the deposition material must be changed,which requires rapid mechanical movement of vacuum *** mechanical components can be regarded as a risk factor for contamination during the coating process,which limits the quality of high-end laser *** minimize the particle contamination,we present a novel deposition concept that does not require movable components to change the coating material during the coating process.A magnetic field guiding technique has been developed,which enables the tuning of the refractive index in the layer structure by sputtering mixtures with varying compositions of two materials using a single-ion *** versatility of this new concept is demonstrated for a highreflection mirror.

关键词： EM field separation ion beam sputtering plasma guiding

Effect of melt-to-solid volume ratio and preheating temperature on Mg/Al bimetals interface by centrifugal casting

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China Foundry 2023年第3期20卷 234-240页

作者： Morteza Sarvari Mehdi Divandari Hassan Saghafan sina Ghaemi Khiavi School of Metallurgy and Materials Engineering Iran University of Science and TechnologyNarmakTehran 16844Iran

Compound casting is an efficient method for bonding dissimilar metals,in which a dramatic reaction can occur between the melt and *** centrifugal casting process,a type of compound casting,was applied to cast Al/Mg dissimilar *** melt was poured at 700 °C,with melt-to-solid volume ratios(Vm/Vs) of 1.5 and 3,into a preheated hollow aluminum *** preheating temperatures of the solid part were 320,400,and 450 °C,and the constant rotational speed was 1,600 *** cast parts were kept inside the casting machine until reaching the cooling temperature of 150 °*** result showed that an increase in preheating temperature from 320 to 450 °C led to an enhanced reaction layer *** addition,an increase in the Vm/Vs from 1.5 to 3 resulted in raising the interface thickness from 1.2 to 1.8 ***,the interface was not continuously formed when a Vm/Vs of 3 was *** this case,the force of contraction overcame the resultant acting force on the *** interface formed at the volume ratio of 1.5 was examined using scanning electron microscopy(SEM) equipped with energy-dispersive X-ray spectroscopy(EDS),and the results demonstrated the formation of Al_(3)Mg_(2),Al_(12)Mg_(17) and(δ+Al_(12)Mg_(17)) eutectic structures in the interface.

关键词： compound casting centrifugal casting Mg/Al bimetal preheating temperature melt-to-solid volume ratio interface

Chasing the mechanisms of ecologically adaptive salinity tolerance

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Plant Communications 2023年第6期4卷 1-21页

作者： Silvia Busoms sina Fischer Levi Yant Plant Physiology Laboratory Bioscience FacultyUniversitat Auto`noma de BarcelonaBellaterraBarcelona E-08193Spain Future Food Beacon of Excellence University of NottinghamNottingham NG72RDUK School of Biosciences University of NottinghamNottingham NG72RDUK School of Life Sciences University of NottinghamNottingham NG72RDUK

Plants adapted to challenging environments offer fascinating models of evolutionary change. Importantly,they also give information to meet our pressing need to develop resilient, low-input *** mounting environmental fluctuation—including temperature, rainfall, and soil salinity and degradation—this is more urgent than ever. Happily, solutions are hiding in plain sight: the adaptive mechanismsfrom natural adapted populations, once understood, can then be leveraged. Much recent insighthas come from the study of salinity, a widespread factor limiting productivity, with estimates of 20% ofall cultivated lands affected. This is an expanding problem, given increasing climate volatility, rising sealevels, and poor irrigation practices. We therefore highlight recent benchmark studies of ecologicallyadaptive salt tolerance in plants, assessing macro- and microevolutionary mechanisms, and therecently recognized role of ploidy and the microbiome on salinity adaptation. We synthesize insightspecifically on naturally evolved adaptive salt-tolerance mechanisms, as these works move substantiallybeyond traditional mutant or knockout studies, to show how evolution can nimbly ‘‘tweak’’ plantphysiology to optimize function. We then point to future directions to advance this field that intersectevolutionary biology, abiotic-stress tolerance, breeding, and molecular plant physiology.

关键词： adaptation salinity polyploidy microbiome evolution ecology

Movement Trend Alterations in the Periaqueductal Gray(PAG)-Employed Ratbot Navigation Are Correlated with Stimulation Parameters

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Journal of Bionic Engineering 2024年第2期21卷 866-876页

作者： sina Khajei Abed Khorasani Mohammad Reza Afarinesh Vahid Sheibani Neuroscience Research Center Institute of NeuropharmacologyKerman University of Medical SciencesKerman***Iran Cognitive Neuroscience Research Center Institute of NeuropharmacologyKerman University of Medical SciencesKerman***Iran

In previous studies,Periaqueductal Gray(PAG)stimulation was used to stop ratbots from *** to the homology between the PAG and the intercollicular nucleus,which has been used for forward movement in birds,we investigated the possibility of PAG application to induce forward locomotion for the first *** a corridor maze,the traveled distances via PAG electrical stimulation were examined in nine Wistar male rats during three sessions.A custom-designed stimulator was developed to apply the *** results showed reductions in responses to stimulation over ***,the traveled distances had negative slopes during the consecutive trials(in 8 out of the 9 rats),and the slope mean was significantly different from *** was a strong correlation between the stimulation parameters(electric Charge per Phase(CPP)and the Number of Pulses(NP))and the observed *** negative Movement Slopes(MS)were highly correlated with the CPP and the NP,as the Pearson's linear correlation coefficients were−0.87 and−0.79,*** MS-CPP coefficients of determination(R-squared)were also between 0.76 and *** addition,the MS-NP coefficients of determination were between 0.63 and ***,it is concluded that the electrical stimulation parameters influence the behavioral outcomes ***,the PAG area may be considered a suitable candidate for forward locomotion control in the future if the area is harnessed effectively to prevent undesirable chaotic behaviors.

关键词： Periaqueductal Gray(PAG) Navigation Ratbot Animal-robot Forward locomotion Movement slope

Monotonic triaxial experiments to evaluate steady-state and liquefaction susceptibility of Babolsar sand

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2013年第10期14卷 739-750页

作者： Yaser JAFARIAN Ali GHORBANI Siavash SALAMATPOOR sina SALAMATPOOR International Institute of Earthquake Engineering and Seismology Faculty of Engineering University of Guilan International Branch University of Guilan

In this study,drained and undrained triaxial tests under isotropic and anisotropic consolidations were conducted on reconstituted samples of Babolsar sand,which underlies a densely populated,seismic region of the southern coast of the Caspian Sea,Mazandaran,*** was demonstrated that the sand experienced all possible states of liquefiable soil: flow failure,limited flow,and *** steady-state and flow liquefaction lines of this sand were presented and compared with previously tested *** is shown that the initial stress anisotropy can affect the potential of volume change and pore pressure *** steady-state line(SSL),however,remains identical for the isotropically and anisotropically consolidated specimens under drained and undrained *** tests data were then analyzed in order to investigate the liquefaction susceptibility of this sand in terms of parameters such as the state parameter,relative state parameter index,and lateral earth pressure ratio at failure.

关键词： Triaxial test Sand Steady-state Liquefaction susceptibility

Treatment of Hepatitis C Virus Infection in Children Less than 12 Years of Age in Developing Countries

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Journal of Clinical and Translational Hepatology 2014年第4期2卷 247-252页

作者： sina Aziz Abbasi Shaheed Hospital Karachi Medical and Dental College Karachi Pakistan

The treatment of hepatitis c virus (HCV) infection in children is difficult as few options are available. The standard therapy is combination pegylated interferon (PEG–IFN) α-2a or 2b and ribavirin, and the duration of therapy depends on HCV genotype. New oral drug therapies available for adults have stil not been approved for treatment in children. Here, we review the causes of HCV infection in children, the therapeutic options for children, and the side effects of these treatments. The problems faced by physicians managing HCV infection in children less than 12 years of age in a developing country are also discussed.

关键词： Hepatitis C Chronic Child Therapeutics Developing countries