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کاربرد نوع شرط:
- جایگاه : پژوهشی
- مجله: Biquarterly Iranian Journal of Analytical Chemistry
- نوع مقاله: Journal Article
- کلمات کلیدی: Adsorption,Scanning electron microscopy,X-ray diffraction,Removal
- چکیده: در این تحقیق پلی استایرن–آلترناتیو-مالئیک انیدرید و مشتقاتی از آن باملامین و ملامین و1،2دی آمینواتان و1،3 دی آمینوپروپان به ترتیب سنتز شدهاند. این روش یک روش بسیار ساده، ارزان، دقیق و پلیمرهای بکار رفته توانایی هفت بار بازگردانی را دارند. در این پژوهش قدرت جذب پلی استایرن–آلترناتیو-مالئیک انیدرید-ملامین ومشتقات آن برای حذف یونهای نقره از محلولهای آبی مورد بررسی قرار گرفته و این جاذبها برای این کار پیشنهاد شدهاند. دراین تحقیق اثر هر یک از پارامترهای مختلف مؤثر بر جاذب در فرآیند حذف یونهای نقره مورد مطالعه و بررسی قرار گرفته و اثر هر یک از آنها بهینه شده است (نظیر زمان جذب، زمان تماس، مقدار جاذب، سرعت چرخش شیکر). بیشترین حذف یون نقره در 6= pH اتفاق افتاده است و زمان تماس بهینه برای یونهای نقره 60 دقیقه است. بیشترین ظرفیت جذب CSMA-MP, CSMA-ME, CSMA-M به ترتیب برابر 67.57، 76.90 و 95.24 بوده است. چنانچه مشخص شده است این جاذبها برای حذف یونهای نقره از محلولهای آبی مناسب میباشند. این رزینها بوسیله آنالیز FT-IR, SEM, XRD, DSC, TGA مشخص شده اند.
- چکیده انگلیسی: In this research poly (Styrene–Alternative-Maleic Anhydride) (SMA) and derivations of SMA with Melamine, (Melamine + 1,2 Diamino Ethane) and (Melamine + 1,3 Diamino Propane) CSMA-M, CSMA-ME and CSMA-MP were synthesized, respectively. This method is very simple, cheap, precise and used polymers recyclable to seven terms. The purpose of the present work was exploring the adsorption power of CSMA-M and its derived polymer to removed silver(I) ions from aqueous solution. In this research, batch adsorption tests were exhibited and the effect of different parameters on this removal process has been studied. The effects of pH, adsorption time, metal ion concentration and the acidic remedy on the adsorption process were optimized. The optimum pH for adsorption was found to be 6.0. In adsorption explores, remained Ag+ concentration arrives equilibrium in a short duration of 60 min. Maximum adsorption capacity, 67.57, 76.90 and 95.24 mg Ag+/g polymer CSMA-M, SMA–ME and SMA–MP respectively.showed that this adsorbents were appropriate for removing silver(I) from aqueous solution. The resins were characterized by Fourier transform Infra Red(FT-IR) spectroscopy, Scanning Electron Microscopy (SEM), X-ray diffraction(XRD) and Differential Scanning Calorimetry (DSC), (Thermo Gravimetric Analysis) TGA analysis.
- انتشار مقاله: 27-04-1396
- نویسندگان: Reza Ansari,Naser Samadi,Bakhtiar Khodavirdilo
- مشاهده
- جایگاه : پژوهشی
- مجله: Biquarterly Iranian Journal of Analytical Chemistry
- نوع مقاله: Journal Article
- کلمات کلیدی: Scanning electron microscopy,X-ray diffraction,Removal of Manganese,Chelating Resins
- چکیده: در این مطالعه رزینهای کیلیتی بهعنوان مواد مناسبی برای بازیابی منگنز (II) از محلولهای آبی مورد ارزیابی قرار گرفت. این رزینهای اصلاح شده در حضور اشعه ماواربنفش با 1و2-دی آمینو اتان واکنش داد تا یک رزین سه بعدی در مقیاس نانو حاصل شود. رزین مورد استفاده در این کار کوپلیمری از پلی استایرن/مالئیک انیدرید بود که با روش جذب اتمی حذف یونهای منگنز از محلول آبی مورد مطالعه قرار گرفت. روش ساده، حساس، ارزان و سریع میباشد. رفتار جذبی رزین در pHهای مختلف ارزیابی شد که نشان داد حتی در pH های اسیدی نیز حذف یونهای انتخاب شده انجام میشود. رزین مورد اشاره جهت حذف منگنز از نمونههای حقیقی نظیر آب فاضلابهای صنعتی بهکار رفت که نتایج خوبی از حیث کارایی حاصل شد. معادلات سینتیکی نفوذ درونذرهای، شبه مرتبه دوم و شبه مرتبه اول برای شبیهسازی دادههای جذبی بهکار رفت و نشان داد، دادهها با رفتار سینتیکی شبه مرتبه دوم مطابقت دارد. مشخصهیابی رزین با روشهای FT-IR، SEM و XRD انجام شد.
- چکیده انگلیسی: In this study chelating resins have been considered to be suitable materials for the recovery of Manganese(II) ions in water treatments. These modified resins were further reacted with 1,2-diaminoethan in the presence of ultrasonic irradiation for the preparation of a tridimensional chelating resin on the Nano scale for the recovery of Manganese II) ions from aqueous solutions. In this work we used copolymers derivate resin of poly (styrene – Alternative - Maleic Anhydride) and Atomic Absorption Spectroscopy for removing and determining Manganese(II) ions .The method is simple, sensitive, inexpensive and fast. The adsorption behavior of Manganese(II) ions were investigated by the synthesis of chelating resins at various pH’s. The prepared resins showed a good tendency for removing the selected metal ions from aqueous solution, even at acidic pH. Also, the prepared resins were examined for the removal of Manganese(II) ions from real samples such as industrial wastewater and were shown to be very efficient at adsorption in the cases of Manganese(II) ions . The pseudo-first-order, pseudo-second-order and intra-particle diffusion kinetics equations were used for modeling of adsorption data and it was shown that pseudo-second-order kinetic equation could best describe the adsorption kinetics. The intra-particle diffusion study revealed that external diffusion might be involved in this case. The resins were characterized by Fourier transform infrared spectroscopy, scanning electron microscopy, X-ray diffraction analysis.
- انتشار مقاله: 15-12-1394
- نویسندگان: Naser Samadi,Reza Ansari,Bakhtiar Khodavirdilo
- مشاهده
- جایگاه : پژوهشی
- مجله: International Journal of Nano Dimension
- نوع مقاله: Journal Article
- کلمات کلیدی: Shear Modulus,Density functional theory,Young’s Modulus,Bulk modulus,Graphitic carbon-nitride
- چکیده:
- چکیده انگلیسی: Successful synthesis of the stable metal-free two-dimensional polymer graphitic carbon-nitride with remarkable properties has made it as one of the most promising nanostructures in many novel nanodevices, especially photocatalytic ones. Understanding the mechanical properties of nanostructures is of crucial importance. Thus, this study employs density functional theory (DFT) to obtain the mechanical properties of graphene-like graphitic carbon-nitride (g-C3N4) nanosheets such as Young’s, bulk and shear moduli and Poisson’s ratio. Based on the results, Young’s, bulk and shear moduli of this nanosheet are lower than those of graphene and hexagonal boron-nitride sheet. Besides, it is observed that the values of the aforementioned properties for graphene-like g-C3N4 nanosheets are higher than those of porous graphene and SiC. It is further observed that the Poisson’s ratio of graphene-like g-C3N4 nanosheets is lower than those of any similar two-dimensional graphitic structures.
- انتشار مقاله: 19-11-1395
- نویسندگان: Shahram Ajori,Reza Ansari,Sina Malakpour
- مشاهده
- جایگاه : پژوهشی
- مجله: Interdisciplinary Journal of Virtual Learning in Medical Sciences
- نوع مقاله: Journal Article
- کلمات کلیدی: Students,nursing,Team-Based Learning,Learning Objectives,Merrill’s First Principles of Instruction
- چکیده:
- چکیده انگلیسی: Introduction Team-based learning is one of the methods concerned in medical education. Teaching and learning have some principles known as Merrill’s first principles that are a basis for effective education. This study examined the effect of using team-based learning combined with Merrill’s Principles on achieving learning objectives in nursing students. Methods This was a semi-experimental, applied research that used pretest-posttest design with a control group. The statistical population included all undergraduate students of Ardebil University of Medical Sciences, Meshkin Shahr campus, in 2015 - 2016. The sample group comprised a class of nursing students selected by convenience sampling method (n = 47). The subjects were divided into two groups of control (n = 23) and test (n = 24) using simple random allocation. A pretest was given to both groups prior to the implementation of the training. Then, the intended plan was executed for 5 weeks and at the end, a posttest was administered. The data were analyzed by applying covariance analysis test using SPSS version 20. Results The results showed that the learning objectives scores in the test group increased from 2.68 and 1.31 to 17.83 and 12.16 for remembrance and application levels, respectively, while the increments were not significant in the control group. In other words, there was a significant difference in the achievement of learning objectives between the test and control groups (P < 0.001), implying that the test group had better learning. Conclusions By using team-based learning combined with Merrill’s First Principles, we can improve learning objectives achievements.
- انتشار مقاله: 11-10-1348
- نویسندگان: Mehdi Badali,Sadaf Alizadeh Derakhshi,Parisa Bagheri,Mohammad Reza Ansari
- مشاهده
- جایگاه : پژوهشی
- مجله: Computational Methods for Differential Equations
- نوع مقاله: Journal Article
- کلمات کلیدی: Asymptotic behavior,Fractional Ostrovsky equation,Wright function,Airy function
- چکیده:
- چکیده انگلیسی: In this paper, we find an integral representation for the fundamental solution of the fractional Ostrovsky equation in terms of the Airy and Bessel-Wright functions. The equation is studied in the sense of the Weyl fractional derivative and the solution is presented as the Airy transforms of Wright functions. Using the asymptotic expansion of Wright function the asymptotic behavior of solution is also discussed.
- انتشار مقاله: 19-01-1397
- نویسندگان: Hassan Askari,Alireza Ansari
- مشاهده
- جایگاه : پژوهشی
- مجله: Computational Methods for Differential Equations
- نوع مقاله: Journal Article
- کلمات کلیدی: Fifth order time-fractional dispersive equation,Conformable context,Invariant subspace method,Fractional Sumudu’s transform,A new exact solution
- چکیده:
- چکیده انگلیسی: During the past years, a wide range of distinct approaches has been exerted to solve the nonlinear fractional differential equations (NLFDEs). In this paper, the invariant subspace method (ISM) in conjunction with the fractional Sumudu’s transform (FST) in the conformable context is formally adopted to deal with a nonlinear conformable time-fractional dispersive equation of the fifth order. As an outcome, a new exact solution of the model is procured, corroborating the exceptional performance of the hybrid scheme.
- انتشار مقاله: 30-01-1397
- نویسندگان: Kamyar Hosseini,Zainab Ayati,Reza Ansari
- مشاهده
- جایگاه : پژوهشی
- مجله: Computational Methods for Differential Equations
- نوع مقاله: Journal Article
- کلمات کلیدی: Riemann-Liouville fractional derivative,Asymptotically stable,Prabhakar fractional derivative,Generalized Mittag-Leffer function
- چکیده:
- چکیده انگلیسی: In this article, we survey the asymptotic stability analysis of fractional differential systems with the Prabhakar fractional derivatives. We present the stability regions for these types of fractional differential systems. A brief comparison with the stability aspects of fractional differential systems in the sense of Riemann-Liouville fractional derivatives is also given.
- انتشار مقاله: 14-06-1395
- نویسندگان: Mohammad Hossein Derakhshan,Mohammadreza Ahmadi Darani,Alireza Ansari,Reza Khoshsiar Ghaziani
- مشاهده
- جایگاه : پژوهشی
- مجله: Computational Methods for Differential Equations
- نوع مقاله: Journal Article
- کلمات کلیدی: Fractional hybrid differential equations,Distributed order,Extremal solutions,Banach algebra
- چکیده:
- چکیده انگلیسی: In this article, we prove the existence of extremal positive solution for the distributed order fractional hybrid differential equation
$$int_{0}^{1}b(q)D^{q}[frac{x(t)}{f(t,x(t))}]dq=g(t,x(t)),$$
using a fixed point theorem in the Banach algebras. This proof is given in two cases of the continuous and discontinuous function $g$, under the generalized Lipschitz and Caratheodory conditions.- انتشار مقاله: 16-10-1392
- نویسندگان: Hossein Noroozi,Alireza Ansari
- مشاهده
- جایگاه : پژوهشی
- مجله: Asian Journal of Green Chemistry
- نوع مقاله: Journal Article
- کلمات کلیدی: Graphene Oxide,Langmuir isotherm,Elimination,Melamine-Butanedioic acid
- چکیده:
- چکیده انگلیسی: In this research, a new method that used graphene oxide (GO) nanosheets melamine butanedioic acid (GO-MB) composites and derivation of poly (Styrene–alternative-maleic anhydride) (SMA), (SMA + melamine-butanedioic acid) (SMA-MB) is presented as sorbents for the elimination of zinc(II) ions from aqueous solutions. The adsorbents have the sufficiency to adsorb the zinc(II) ions. Through immobilizing the melamine-butanedioic acid onto GO nanosheets and SMA-MB, the desired composite was synthesized and identified by field emission scanning electron microscopy (FE-SEM) and fourier transform infrared (FT-IR) spectroscopy techniques. Some experimental parameters including, pH, concentration of the aqueous solution of zinc(II) ions, the content of the zinc(II) ions, the grapheme oxide-melamine-butanedioic acid, and SMA-MB were optimized. The results showed that, the adsorbents were matched with langmuir isotherm. It was also revealed that the uptake efficiency of zinc(II) ions considerably increased after immobilization of melamine-butanedioic acid on the GO nanosheets and SMA. These adsorbents were also shown to be very suitable to remove the zinc(II) ions from aqueous solutions.
- انتشار مقاله: 03-05-1397
- نویسندگان: Naser Samadi,Reza Ansari,Bakhtiar Khodavirdilo
- مشاهده
- جایگاه : پژوهشی
- مجله: Asian Journal of Green Chemistry
- نوع مقاله: Journal Article
- کلمات کلیدی: Chelating adsorbents,Langmuir isotherm,Prunus Cerasus Rock,Adsorption capacities
- چکیده:
- چکیده انگلیسی: Chelating adsorbents have been considered to be suitable materials for the recovery of cadmium in water treatments. Adsorption of Cadmium (II) ions on melamine-butanedioic acid, modified poly (Styrene-alternative-maleic anhydride) cross-linked by 1, 2-diaminobutane (CSMA-MB) and pit shell of sour cherry (Prunus cerasus rock) (PCR) as an ion exchange adsorbents have been investigated in aqueous solution. The adsorption behavior of these Cadmium (II) ions on the adsorbents was studied by varying the parameters such as pH (2-8), adsorbent dose (0-4.0 g/L-1), contact time (0‒240 min), and Cadmium (II) ion concentration (20-300 mg/L-1). Adsorption percentage was increased by increasing each of these parameters. The isotherm models such as Langmuir, Freundlich, Temkin, and Dubinin-Radushkevich were used to describe adsorption equilibrium. The results showed that the best fit was achieved with the Langmuir isotherm equation, yielding maximum adsorption capacities of 81.30, 80.42 mg/g-1 for Cd (II) with CSMA-MB and PCR respectively. Both adsorbents, CSMA-MB and PCR, are very suitable for the removal Cadmium (II) ions from aqueous solutions. The adsorbents were characterized by fourier transform infrared spectroscopy (FT-IR), scanning electron microscopy (SEM), x-ray diffraction analysis (XRD).
- انتشار مقاله: 17-10-1396
- نویسندگان: Naser Samadi,Reza Ansari,Bakhtiar Khodavirdilo
- مشاهده