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Perfluoroalkyl acid transformation and mitigation by nNiFe-activated carbon nanocomposites in steady-state flow column studies

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Journal of Environmental Sciences 2023年第5期127卷 678-687页

作者： mahsa modiri-gharehveran Younjeong Choi Jenny E.Zenobio Linda S.Lee Department of Agronomy Purdue UniversityWest LafayetteIN 47907USA Interdisciplinary Ecological Sciences&Engineering Purdue UniversityWest LafayetteIN 47907USA

The ongoing contamination of groundwater with per-and polyfluoroalkyl substances(PFAS)has resulted in a global and rapidly growing interest in PFAS groundwater *** technologies that lead to PFAS destruction are often limited by not addressing all PFAS,being energy-intensive or not being suited for in-situ *** developed nNiFeactivated carbon(AC)nanocomposites and demonstrated varying degrees of PFAS reduction and fluoride generation with these nanocomposites in batch reactors for several *** we explore nNiFe-AC’s effectiveness to transform perfluoroalkyl acid acids(PFAAs)under steady-state flow(0.0044 to 0.15 mL/min)in nNiFe-AC:sand packed *** experiments included,two perfluorooctane sulfonate(PFOS)in deionized water and two PFAA mixtures in deionized water or bicarbonate buffer containing five perfluoroalkyl carboxylates(PFCAs,C5-C9)and three perfluoroalkyl sulfonates(PFSAs,C4,C6 and C8)at temperatures of 50 or 60℃ were *** transformation was similar in PFOS-only and PFAA mixture column ***,%PFAA transformation under flow conditions exceeded what we observed previously in batch reactors with up to 53%transformation of a PFAA mixture with∼8%*** chain PFAS dominated the PFAAs transformed and a bicarbonate matrix appeared to reduce overall *** breakthrough was slower than predicted from only sorption due to transformation;some longer chain PFAS like PFOS did not ***,nNiFe-AC technology with both in-situ and ex-situ potential application was shown to be a plausible part of a treatment train needed to address the ongoing challenge for cleaning up PFAS-contaminated waters.

关键词： PFAAs PFAS Zero valent iron Nanoparticles Remediation Groundwater

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Yttrium-iron garnet and yttrium orthoferrite nanocrystals:Hydrothermal synthesis, magnetic property and phase transformation study

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Journal of Rare Earths 2018年第12期36卷 1292-1298页

作者： Mohammadreza Mansournia mahsa Orae Department of Inorganic Chemistry Faculty of Chemistry University of Kashan

In this work,we present a new and fast method to obtain the single phase YFeO(YIG,cubic) and YFeO(YIP, orthorhombic) nanocrystals based on hydrothermal technique. The influence of initial Y/Fe mole ratio and calcination temperature on the nature, purity, phase structure, and morphology of the product was investigated by X-ray diffraction(XRD), Fourier-transform infrared(FT-IR) spectroscopy,energy-dispersive(EDX) X-ray spectroscopy, and field emission scanning electron microscopy(FESEM).The results show that the transformation of the as-synthesized YIG from amorphous to orthorhombic and finally to cubic phase occurs with the increase of annealing temperature. On this basis, the pure cubic phase YIG can be obtained by calcination(at 1100℃) of the precursor which is prepared using the hydrothermal treatment of mole ratio of Y:Fe = 1:1.5 exposure to an ammonia atmosphere. Also, the initial Y/Fe mole ratio of 1:1 and calcination temperature of 1000 ℃ are the optimal conditions to form single-phase nanocrystalline YIP. Further, vibrating sample magnetometry(VSM) measurements illustrate the average magnetic saturation, coercivity and remanence of 2.73 and 15.00 emu/g, 42.74 and40.02 Oe, and 1.65 and 4.30 emu/g for YIP and YIG nanocrystals, revealing their soft ferromagnetic character.

关键词： Yttrium-iron garnet Yttrium orthoferrite Ammonia atmosphere Nanoparticles Magnetic materials Phase transformation

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Vault RNAs(vtRNAs):Rediscovered non-coding RNAs with diverse physiological and pathological activities

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Genes & Diseases 2024年第2期11卷 772-787页

作者： mahsa Aghajani Mir Deputy of Research and Technology Health Research InstituteBabol University of Medical SciencesBabol 47176-4774Iran

The physicochemical characteristics of RNA admit non-coding RNAs to perform a different range of biological acts through various mechanisms and are involved in regulating a diversity of fundamental ***,some reports of pathological conditions have proved abnormal expression of many non-coding RNAs guides the *** RNAs are a class of non-coding RNAs containing stem regions or loops with well-conserved sequence patterns that play a fundamental role in the function of vault particles through RNA-ligand,RNA–RNA,or RNA-protein *** together,vault RNAs have been proposed to be involved in a variety of functions such as cell proliferation,nucleocytoplasmic transport,intracellular detoxification processes,multidrug resistance,apoptosis,and autophagy,and serve as microRNA precursors and signaling *** decades of investigations devoted,the biological function of the vault particle or the vault RNAs is not yet completely *** this review,the current scientific assertions of the vital vault RNAs functions were discussed.

关键词： ncRNA Vault complex Vault RNA vtRNA viral infection tumorigenesis

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Software Agent with Reinforcement Learning Approach for Medical Image Segmentation

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Journal of Computer Science & Technology 2011年第2期26卷 247-255页

作者： mahsa Chitsaz Chaw Seng Woo Faculty of Computer Science and Information Technology University of Malaya

Many image segmentation solutions are problem-based. Medical images have very similar grey level and texture among the interested objects. Therefore, medical image segmentation requires improvements although there have been researches done since the last few decades. We design a self-learning framework to extract several objects of interest simultaneously from Computed Tomography （CT） images. Our segmentation method has a learning phase that is based on reinforcement learning （RL） system. Each RL agent works on a particular sub-image of an input image to find a suitable value for each object in it. The RL system is define by state, action and reward. We defined some actions for each state in the sub-image. A reward function computes reward for each action of the RL agent. Finally, the valuable information, from discovering all states of the interest objects, will be stored in a Q-matrix and the final result can be applied in segmentation of similar images. The experimental results for cranial CT images demonstrated segmentation accuracy above 95%.

关键词： biomedical image segmentation multi-agent systems reinforcement learning system CT images

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Fabrication of novel ZnO/MnWO_4 nanocomposites with p-n heterojunction: Visible-light-induced photocatalysts with substantially improved activity and durability

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Journal of Materials Science & Technology 2018年第10期34卷 1891-1901页

作者： mahsa Pirhashemi Aziz Habibi-Yangjeh Department of Chemistry Faculty of Science University of Mohaghegh Ardabili P.O. Box 179 Ardabil Iran

We report, for the first time, binary ZnO/MnW04 nanocomposites with p-n heterojunction fabricated by a simple ultrasonic-calcination route. The phase structure, morphology, and optical along with tex- tural properties were comprehensively characterized. The photocatalytic performance was studied via degradations of rhodamine B, methyl blue and methyl orange （RhB, MB, MO）, and fuchsine pollutants under visible-light illumination. The ZnO/MnW04 nanocomposites exhibited better photocatalytic per-formance than their single components and the nanocomposite with 30 wt% MnW04 showed the highest activity. Photocatalytic performance of this nanocomposite is 22.5, 17.7, 26.8, and 23.9 times higher than that of the ZnO sample in degradations of RhB, MB, MO, and fuchsine dyes, respectively. The improved photocatalytic performance was ascribed to the formation ofp-n heterojunction between ZnO and MnW04 with high charge separation efficiency as well as strong visible-light absorption ability. The possible mechanism for the improved photocatalytic performance was proposed. This study revealed that the novel ZnO/MnW04 p-n heterojunction can act as a promising visible-light-active photocatalyst for environmental applications.

关键词： ZnO/MnW04 p-n heterojunction Visible-light-active Photocatalyst

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Predictors of colorectal cancer testing using the California Health Inventory Survey

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World Journal of Gastroenterology 2013年第8期19卷 1247-1255页

作者： Alexandra modiri Kian Makipour Javier Gomez Frank Friedenberg Section of Gastroenterology Department of MedicineTemple University HospitalPhiladelphiaPA 19140United States

AIM:To identify key variables associated with colon cancer testing using the 2009 California Health Inventory Survey(CHIS).METHODS:The CHIS has been conducted biennially since 2001 using a two-stage,geographically stratified random-digit-dial sample design to produce a representative sample of the entire *** this study we used survey data from 2001-2009 *** restricted our analysis to White,Black,and Hispanic/Latinos aged 50-80 *** data was used to calculate the proportion of participants who underwent some form of colon cancer testing(colonoscopy,flexible sigmoidoscopy or fecal occult blood testing) within the previous 5 years stratified by race/*** inferential analysis,boot-strapping with replacement was performed on the weighted sample to attain variance estimates at the 95%*** mean differences among categories we used t-tests and for comparisons of categorical data we used Pearson's χ *** logistic regression was used to identify independent variables associated with undergoing some form of *** analysis was performed to determine rates of testing over the study period stratified by ***:The CHIS database for 2009 had 30 857 unique respondents corresponding to a weighted sample size of 10.6 million ***,63.0%(63.0-63.1) underwent a colon cancer test within the previous 5 years;with 70.5%(70.5%-70.6%) of this subset having undergone *** is 44.5%(44.4%-44.5%) of all individuals 50-80 underwent *** multivariable regression,those tested were more likely to be male(OR = 1.06;95%CI:1.06-1.06),Black(OR = 1.30;95%CI:1.30-1.31),have a family member with colon cancer(OR = 1.71;95%CI:1.70-1.72),and have health insurance(OR = 2.71;95%CI:2.70-2.72).Progressive levels above the poverty line were also associated with receiving a test(100%-199%:1.21;1.20-1.21),(200%-299%:1.41;1.40-1.42),(> 300:1.69;1.68-1.70).The strongest variable was physician recommendation(OR = 3.90;95%CI:3.88

关键词： California Health Inventory Survey Colon cancer testing Colonoscopy Hispanic

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One-step synthesis of Ni@Pd/NH_(2)-Fe_(3)O_(4)nanoparticles as affordable catalyst for formic acid dehydrogenation

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Chinese Journal of Chemical Engineering 2021年第4期34卷 168-174页

作者： Mohammad Reza Nabid Yasamin Bide mahsa Jafari Department of Polymer&Material Chemistry Faculty of Chemistry&Petroleum ScienceShahid Beheshti UniversityTehran ***Iran

Currently,one of the critical issues in the world is finding an appropriate green alternative to fossil fuels due to the concerns about global *** a hydrogen source,formic acid has been given particular attention owing to the attractive features such as highenergy density,no toxicity,high stability at ambient temperature and high hydrogen *** an affordable and highly efficient catalyst with easy recovery from the reaction mixture for selective dehydrogenation of formic acid is still *** this report,we used a simple onestep process to synthesize Ni@Pd core shell nanoparticles on 3aminopropyltriethoxysilane modified Fe3O4 *** existence of Ni and Pd results in a synergic effect on the catalytic ***—NH2 groups play an important role for obtaining welldispersed ultrafine particles with high surface area and active *** addition,Fe3O4 lead to convenient magnetic recovery of the catalyst from reaction *** results indicate that the asprepared catalyst give the superb turnover frequency of 5367.8 h 1 with no additive,which is higher than most of the previously reported catalysts.

关键词： Core-shell Fe_(3)O_(4) Catalysis Dehydrogenation Formic acid

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Hydrothermal synthesis and physicochemical characterization of CuO/ZnO/Al_2O_3 *** I:Effect of crystallization time

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Particuology 2012年第6期10卷 729-736页

作者： Saeed Saedy Mohammad Haghighi mahsa Amirkhosrow Chemical Engineering Department Sahand University of TechnologyP.O.Box 51335-1996Sahand New TownTabrizIran Reactor and Catalysis Research Center Sahand University of TechnologyP.O.Box 51335-1996Sahand New TownTabrizIran

A hydrothermal method was successfully used for synthesis of CuO/ZnO/AI203 （CZA） nanopowder with atomic ratio of 6：3：1. The effect of crystallization time （3, 6, 9, and 12 h） on physicochemical properties of nanopowder was investigated. Nanopowders were characterized using XRD, FESEM, EDX, FTIR, TG, and BET techniques. The XRD patterns confirmed metal oxides formation and their good crystallinity with average crystallite size of 20nm as obtained by the Scherrer equation. Relative crystallinity was shown to increase with increasing crystallization time. In agreement with XRD results, FESEM images also illustrated nanosized particles. EDX mapping indicated homogenous dispersion of elements. BET specific surface area analysis showed acceptable surface area for CZA nanopowder, FTIR spectroscopy confirmed metal oxides formation during hydrothermal and calcination processing. TG results illustrated high thermal stability of the synthesized nanopowders. TG-DTG and FTIR analyses were used to propose a reaction mechanism for nanopowder formation during processing. Physicochemical characterization showed optimal crystallization time to be 6 h.

关键词： ZnO CuO Al2O3 Mixed oxides Nanopowder Hydrorhermal

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An investigation into the properties of ternary and binary cement pastes containing glass powder

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Frontiers of Structural and Civil Engineering 2019年第3期13卷 741-750页

作者： Marcelo Frota BAZHUNI mahsa KAMALI Ali GHAHREMANINEZHAD Department of Civil Architectural and Environmental EngineeringUniversity of MiamiCoral GablesFL 33146USA

The properties of binary and ternary cement pastes containing glass powder (GP) were *** at early age was evaluated using semi-adiabatic calorimetry and at late ages using non-evaporable water content and thermogravimetric *** transport characteristic was assessed by measuring electrical *** binary paste with slag showed the highest hydration activity compared to the binary pastes with GP and fly ash (FA).The results indicated that the pozzolanic behavior of the binary paste with GP was less than that of the binary pastes with slag or FA at late *** increase in the electrical resistivity and compressive strength of the binary paste with GP compared to other modified pastes at late ages was *** was shown that GP tends to increase the drying shrinkage of the *** pastes containing GP did not exhibit synergistic enhancements compared to the respective binary pastes.

关键词： cement paste glass powder pozzolanic reaction supplementary cementitious material

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Sensitivity of optimal double-layer grid designs to geometrical imperfections and geometric nonlinearity conditions in the analysis phase

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Frontiers of Structural and Civil Engineering 2024年第8期18卷 1209-1224页

作者： Amirali REZAEIZADEH mahsa ZANDI Majid ILCHI GHAZAAN School of Civil Engineering Iran University of Science and TechnologyTehran 16846-13114Iran

This study focuses on exploring the effects of geometrical imperfections and different analysis methods on the optimum design of Double-Layer Grids(DLGs),as used in the construction industry.A total of 12 notable metaheuristics are assessed and contrasted,and as a result,the Slime Mold Algorithm is identified as the most effective approach for size optimization of *** evaluate the influence of geometric imperfections and nonlinearity on the optimal design of real-size DLGs,the optimization process is carried out by considering and disregarding geometric nonlinearity while incorporating three distinct forms of geometrical imperfections,namely local imperfections,global imperfections,and combinations of *** light of the uncertain nature of geometrical imperfections,probabilistic distributions are used to define these imperfections randomly in direction and *** results demonstrate that it is necessary to account for these imperfections to obtain an optimal ***’s worth noting that structural imperfections can increase the maximum stress ratio by up to 70%.The analysis also reveals that the initial curvature of members has a more significant impact on the optimal design of structures than the nodal installation error,indicating the need for greater attention to local imperfection issues in space structure construction.

关键词： double-layer grid sizing optimization metaheuristic algorithms geometrical imperfections analysis approach

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