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Fe3O4/CoWO4 magnetic nanocomposites with spherical morphology were synthesized by simple method. The crystal structures, morphology and chemical properties of the as-synthesized nanoparticles were characterized using scanning electron microscopy, transmission electron microscopy, energy dispersive X-ray, X-ray diffraction, and vibrating sample magnetometer techniques. The photocatalytic activity of Fe3O4/CoWO4 magnetic nanocomposites was investigated by degradation of rhodamine B (RhB) in aqueous solution under visible light irradiation. The results indicate that about 98% of RhB were degraded after 180 min. The antimicrobial activity of Fe3O4/CoWO4 nanocomposites were investigated. [ABSTRACT FROM AUTHOR]

N,N-dichloropolystyrene sulfonamide as a decontaminant was synthesized in 5 steps from styrene monomer. Styrene was first polymerized. Then, sulfonation reaction was performed by H2SO4 (c) followed by chlorination with POCl3 obtain chlorosulfonated polystyrene. Amidification reaction was then applied to get sulfonamide resin. Sulfonamide resin was treated with sodium hypochloride to obtain N,N-dichloropolystyrene product. The products of each step were characterized by FT-IR technique. The active chlorine content of final product was measured by standard iodometry titration. Composite nanofibers of polystyrene - N,N-dichloropolystyrene sulfonamide (PS/DPSA) were prepared with electrospinning technique. The appropriate nanofibers obtained under optimized conditions such as applied voltage, distance between the collection plate and nozzle, kind of solvent and concentration of composite solution. The diameter of nanofibers was determined by scanning electron microscope (SEM) and range of nanofiber was about 160-300nm. The decontamination reaction of 2-chloroethyl ethyl sulfide (2-CEES) a simulant of sulfur mustard (S.M.) by composite nanofibers of PS/ DPSA was monitored by gas chromatography (GC). Also the reaction products of decontamination reaction were identified by gas chromatography - mass spectroscopy (GC-MS). These composite nanofibers are able to decontaminate 2-CEES in 7 minutes. [ABSTRACT FROM AUTHOR]

Recombinant protein purification is a kind of sensitive and expensive method in genetics engineering. Genetic manipulation leads to the expression of various proteins; it should be isolated with high purity finally. Differed methods for protein purification are categorized, based on cast, quality, Easy work and side effect of protein. In this article, we are investigating his His-tag protein purification by magnetic nanoparticles. NiFe2O4 nanoparticles were synthesized by Co-precipitation method, than was dissolved in 0.05 NaCl solutions. Tube containing of nanoparticles and buffer was located in magnetic field. Nanoparticles were separation by the three-stage washed. According to the protocols, nanoparticles located in his-tag protein and the end protein were predicated, and analyzed by the Electrophoreses. The results of gel showed can be extracted that the proteins form a weak that the results of gel showed that proteins isolated are poor by this method. By supplementary study, we get new age or tree-age nanoparticles, that Ni is the surface of N.P. This age of nanoparticles is fit to protein purification. Nano-particle synthesis in this article, are created a two-dimensional grid of nickel and iron oxide nanoparticles that this structure is not suitable for purification of His-tag protein. So the magnetic nanoparticles have a three-dimensional structure of the nickel nanoparticles on the surface of the exposed histidine to be enough space to connect and link. It is hoped in future studies with these types of nanoparticles synthesis to achieved His-protein isolation kit. [ABSTRACT FROM AUTHOR]

تشكل البنوك الإسلامية إحدى أهم مكونات الجهاز المصرفي لاسيما لدى الدول التي أدركت ضرورة تبني هذا النوع من البنوك ضمن نظامها التمويلي، وذلك بالنظر لكونها بمثابة وعاء يقوم باستيعاب واستغلال رؤوس أموال المودعين الذين يتجنبون التعامل مع البنوك التقليدية، بالإضافة إلى تحقيقها لأهداف ذات طابع شمولي تتلاءم وأهداف الدولة، وفي هذا الإطار نشأت علاقة في اتجاهين بين السلطات النقدية وهذا النوع من البنوك كاستجابة وضرورة ملحة لتنظيم سبل وأدوات التعامل بين الجانبين، مع الأخذ بالاعتبار شرط أن يحتفظ البنك المركزي بسلطته الرقابة والتوجيهية للبنك الإسلامي بصفة مباشرة أو غير مباشرة من خلال سياساته النقدية والمالية، وقد يلجأ إليه كمقترض في حالات خاصة، بالمقابل فإن البنك الإسلامي يواجه العديد من التحديات والعقبات في ظل هذه العلاقة رغم أنه يمثل مصدر أمن وثقة للمتعاملين ومساهمته في توفير متطلبات التنمية (تسهيلات كبيرة للمشاريع الاستثمارية)، خاصة فيما يتعلق بتعارض العديد من أساليب الرقابة مع المبادئ التي يقوم عليها، وعليه فإنه من الضروري تكييف مختلف إجراءات ومعايير الرقابة المصرفية وفق ما يتلاءم مع أحكام الشريعة الإسلامية. الكلمات المفتاحية: البنك المركزي، البنوك الإسلامية، البنوك الجزائرية.

Abstract: A proton transfer compound L, (MetH)2(dipic), (dipicH2 =2,6-pyridinedicarboxylic acid and Met=Metformin (N,N-dimethylebiguanidine), was synthesized and characterized by IR, 1H and 13C NMR spectroscopy. The reaction of L with PdCl2 in water results in the formation of novel tetracoordinated PdII complex [Pd(dipic)(Met)]·2H2O indicating the participation of both dipic2− and Met as chelating ligands. This complex was characterized by single crystal X-ray analysis. The crystal system is monoclinic with space group P21/c. The unit cell dimensions for PdII complex 1 is a =8.8619(14)Å, b =9.5072(9)Å, c =19.153(3)Å. [Copyright &y& Elsevier]

The following work presents a new, rapid, potential to be portable, convenient, and low-cost method using hollow fiber membrane-protected solid phase microextraction followed by corona discharge ion mobility spectrometry which was used for determining dimethyl methylphosphonate in beverages. Response surface methodology based on the design of Box-Behnken was implemented for optimizing the different factors influencing the proposed method for obtaining the best results. Optimal extractions were calculated with 65 µm polydimethylsiloxane-divinylbenzene fiber, fiber equilibration time of 10 min, stirring rate of the sample solution at 750 rpm, and extraction temperature of 50 °C. The proposed technique provided linear range (0.5-50 µg mL -1 ), good linearity (>0.991), and repeatability (the relative standard deviations of 5.42% and 8.37% of intra- and inter-day analyses, respectively) under the optimized extraction conditions. Finally, the developed method was successfully used for determining dimethyl methylphosphonate in beverages such as coffee mix, fruit juice, tap water, milk, and tea., Competing Interests: Declaration of Competing Interest There are no conflicts of interest., (Copyright © 2021. Published by Elsevier B.V.)

In this paper, a novel solid phase microextraction fiber based on Co 3 O 4 quantum dot incorporated polyacrylamide-co-ethylene glycol dimethacrylate followed by corona discharge ion mobility spectrometry is presented for the trace determination of organophosphorus pesticides in environmental water samples. Ion mobility spectrometry is a comparatively inexpensive, well-known, robust, and easy to operate analytical instrument. This combination would provide a low-cost, fast, selective, and sensitive quantitative system for detection of organophosphorus pesticides. In order to obtain the best extraction efficiency, the optimization of parameters affecting this method was carried out. After optimization, a solution pH of 7.0, extraction temperature of 60 °C, adsorption temperature of 260 °C, extraction time of 30 min, stirring speed of 750 rpm, and ionic strength of 10% w/w were obtained. Consequently, the presented method showed low limits of detection (0.3-0.6 ng mL -1 ), excellent enrichment factors (PF = 221-263), good linearity (R 2 > 0.995), and repeatabilities (intra-day: 3.4 to 4.8%) and (inter-day: 4.7 to 6.1%). The reproducibility (RSD% of fiber to fiber) was also investigated by analyzing three as-prepared fibers under the same conditions and was found to be less than 7.6%. Finally, the developed fiber was used for determination of organophosphorus pesticides in the field samples.

This study focuses on the synthesis of carbon nanotubes decorated with nickel-zinc ferrites and fabrication of polyurethane (PU) nanofiber containing CNT-ferrite composites as highly efficient adsorbents for removal of hydrogen sulfide. Scanning electron microscopy (SEM), transmission electron microscopy (TEM), Fourier transformed infrared (FTIR) spectroscopy, and powder X-ray diffraction (PXRD) are used to perform microstructural and morphological characterization of the electrospun nanofibrous composites. To show the efficiency of the composite as an adsorbent, a breakthrough test is carried out. It is shown that the PU-CNT-ferrite composites are fabricated almost uniformly with an average fiber diameter of 320 nm and exhibit significant H 2 S breakthrough capacity (498 mgH 2 S/g) compared to both the pristine PU and PU-CNT nanofibers. These electrospun nanofibers based on CNT-ferrite composites, already studied for H 2 S adsorption with promising results, open up new and interesting perspective into the design and fabrication of highly efficient membrane for practical application in the processes of air purification.

Unlabelled: The present study aimed to optimize the electrospinning parameters for polyacrylonitrile (PAN) nanofibers containing MgO nanoparticle to obtain the appropriate fiber diameter and mat porosity to be applied in air filtration. Optimization of applied voltage, solution concentration, and spinning distance was performed using response surface methodology. In total, 15 trials were done according to the prepared study design. Fiber diameter and porosity were measured using scanning electron microscopic (SEM) image analysis. For air filtration testing, the nanofiber mat was produced based on the suggested optimum conditions for electrospinning. According to the results, the lower solution concentration favored the thinner fiber. The larger diameter gave a higher porosity. At a given spinning distance, there was a negative correlation between fiber diameter and applied voltage. Moreover, there were curvilinear relationships between porosity and both spinning distance and applied voltage at any concentration. It was also concluded that the developed filter medium could be comparable to the high-efficiency particulate air (HEPA) filter in terms of collection efficiency and pressure drop. The empirical models presented in this study can provide an orientation to the subsequent experiments to form uniform and continuous nanofibers for future application in air purification., Implications: High-efficiency filtration is becoming more important, due to decreasing trends air quality. Effective filter media are increasingly needed in industries applying clean-air technologies, and the necessity for developing the high-performance air filters has been more and more felt. Nanofibrous filter media that are mostly fabricated via electrospinning technique have attracted considerable attention in the last decade. The present study aimed to develop the electrospun PAN-containing MgO nanoparticle (using the special functionalities such as absorption and adsorption characteristics, antibacterial functionality, and as a pore-forming agent) filter medium through experimental investigations for application in high-performance air filters.

Background: Epidermal growth factor (EGF) plays a fundamental role in the healing of wounds relating to skin damage, the cornea, and the gastrointestinal tract., Objectives: The aim of this study is the cloning, expression, and purification of recombinant human EGF (rhEGF), and an assessment of its activity., Materials and Methods: In the present experimental study, a synthetic pET28a (+) -hEGF construct was prepared. In order to ligate hEGF into pET24a (+), the PCR technique was performed, using special primers that possess restriction enzyme sites, which are also located in appropriate sites in pET24a (+). After transferring this construct into E. coli cells, protein expression was performed under standard conditions. Protein solubilization was done by urea. hEGF purification and refolding were carried out using gradient dialysis against the urea. We used RP-HPLC to compare between rhEGF and commercial rhEGF as a control. Finally, an MTT assay was performed to assess the viability of the NIH 3T3 cells treated with various concentrations of rhEGF., Results: Dialysis after urea solubilization caused precipitation of unwanted proteins, resulting in achievement of purified EGF with > 90% purity, without the need for expensive and time-consuming process. The MTT assay results showed that our rhEGF activate significantly higher proliferation of NIH 3T3 cells in comparison to the control (P-values were < 0.0001), in total concentrations and times evaluated, Conclusions: Via our purification protocol, a sufficient amount of bioactive recombinant human epidermal growth factor was obtained in just a few affordable steps, with superlative purity.

In this paper, carbon-coated Fe3 O4 nanoparticles were successfully synthesized and used as a magnetic solid-phase extraction absorbent for the preconcentration and extraction of organophosphorus pesticides in environmental water samples. The carbon-coated Fe3 O4 nanoparticles were characterized by transmission electron microscopy, X-ray powder diffraction, Fourier transform infrared spectroscopy, and vibrating sample magnetometry. The determination of organophosphorus pesticides in water samples with carbon-coated Fe3 O4 nanoparticles was investigated by high-performance liquid chromatography with a diode array detector. Furthermore, the response surface model based on the central composite design was applied to quantitatively investigate the effect of some important variables influencing the extraction efficiency, such as pH, treatment time, amount of nanoparticle sorbents, and amount of salt and to find the optimized conditions providing the highest extraction efficiency. Under optimized conditions, the calibration curve was linear in the range of 0.5-15.0 ng/mL with a regression coefficient of 0.9948, 0.9958, and 0.9931 for fenitrothion, diazinon, and ethion, respectively. The obtained results showed that this analytical method would be useful for the analysis of fenitrothion, diazinon, and ethion in tap water with high precision and accuracy., (© 2015 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.)

A highly sensitive chemiluminescence (CL) method for the determination of 2-chloroethyl ethyl sulfide (2-CEES) was presented. It was found that 2-chloroethyl ethyl sulfide (2-CEES) could inhibit the CL of the luminol-AgNO3 system in the presence of silver nanoparticles in alkaline solution, which made it applicable for determination of 2-CEES. The presented method is simple, convenient, rapid and sensitive. Under the optimized conditions, the calibration curve was linear in the range of 0.0001-1ngmL(-1), with the correlation coefficient of 0.992; while the limit of detection (LOD), based on signal-to-noise ratio (S/N) of 3, was 6×10(-6)ngmL(-1). Also, the relative standard deviation (RSD, n=5) for determination of 2-CEES (0.50ngmL(-1)) was 3.1%. The method was successfully applied for the determination of 2-CEES in environmental aqueous samples., (Copyright © 2015 Elsevier B.V. All rights reserved.)

In this study, a method for extraction and preconcentration trace amounts of organophosphorus pesticides (OPPs) in environmental water was developed using magnetic solid phase extraction (magnetic-SPE) followed by high performance liquid chromatography (HPLC) with UV detection. Magnetite octadecylsilane nanoparticles were synthesized and characterized by X-ray diffraction, FTIR spectroscopy, vibrating sample magnetometry and scanning electron microscopy. These nanoparticles were applied for extraction and preconcentration of OPPs (residues of diazinon and fenitrothion, which are the most-widely used for pest control in Iran) in environmental water samples at low ng mL(-1) concentration as magnetic-SPE adsorbent. The extraction conditions and efficiency of the nanoparticles for OPPs were investigated. The method was evaluated according to the reproducibility, enrichment factor, linearity range and limits of detection. Under optimized conditions, method showed good linearity between 0.03-0.06 and 30 ng mL(-1) with regression coefficients (R(2)) of 0.997 and 0.998. Limits of detection were 0.019 and 0.014 ng mL(-1). The enrichment factors of this method were 172 and 184 and the analysis yielded good reproducibility with the RSD values 7.2% and 5.4% at the 10 ng mL(-1) level (n=5) for diazinon and fenitrothion, respectively. Determination of OPPs can be easily carried out with this fast, accurate, sensitive and simple method procedure., (Copyright © 2012 Elsevier B.V. All rights reserved.)

A multiwavelength spectrophotometric titration method was applied to study the acidity constants of some azo dyes in water. The UV-vis absorption spectra of azo dye solutions were recorded in the course of their pH-metric titration with a standard base solution. The protolytic equilibrium constants, spectral profiles, concentration diagrams and also the number of components have been calculated. The quantitative effects of the substituents on the acidity of the studied azo dyes were investigated by the linear free energy relationship (LFER) using Hammet sigma constant (sigma) and field and resonance effects of Kamlet and Taft (f and Re, respectively).

A highly selective poly(vinyl chloride)-based membrane sensor produced by using N,N-diethyl-N-(4-hydroxy-6-methylpyridin-2-yl)guanidine (GD) as active material is described. The electrode displays Nernstian behavior over the concentration range 7.0 x 10(-5) - 1.0 x 10(-1) M. The detection limit of the electrode is 5.0 x 10(-5) M. The best performance was obtained with the membrane containing 30% PVC, 55% benzyl acetate, 5% GD and 10% oleic acid. The response of the sensor is pH-independent in the range of 3.0 - 7.0. The sensor possesses satisfactory reproducibility, fast response time (< 20 s), and specially excellent discriminating ability for Eu(III) ion with respect to the alkali, alkaline earth, transition and heavy metal ions. The membrane sensor was used as an indicator electrode in potentiometric titration of Eu(III) ion with EDTA. It was also applied in determination of fluoride ions in mouth wash preparations.

The 2,6-diphenyl-4-benzo-9-crown-3-pyridine (DPCP) was used as an excellent ionophore in construction of a coated graphite poly(vinyl chloride) (PVC)-based membrane sensor. The best performance was obtained with a membrane composition of 30% poly(vinyl chloride), 60% o-nitrophenyloctyl ether (NPOE), 5% 2,6-diphenyl-4-benzo-9-crown-3-pyridine and 5% sodium tetraphenyl borate (TBP). This sensor shows very good selectivity and sensitivity towards beryllium ion over a wide variety of cations, including alkali, alkaline earth, transition and heavy metal ions. The sensor revealed a great enhancement in selectivity coefficients and sensitivity for beryllium, in comparison with the previously reported beryllium electrodes. The electrode exhibits a Nernstian behavior (with slope of 29.6mV per decade) over a very wide concentration range (1.0x10(-7) to 1.0x10(-1)) with a detection limit of 4.0x10(-8)M (360pgml(-1)). It shows relatively fast response time, in whole concentration range (<10s), and can be used for at least 12 weeks in the pH range of 4.5-8.0. The proposed sensor was successfully used to determination of beryllium in mineral ore.