Sharif Digital Repository

TiO2-based photocatalysts are seen as the most common agents for the photodegradation of bacteria. In this study, AgCl/TiO2, hydroxyapatite(Hp)/AgCl/TiO2, AgI/TiO2, and Hp/AgI/TiO2 were prepared by the deposition-precipitation method on P25 TiO2 nanoparticles and were characterized by XRD, SEM, FT-IR, EDX and BET methods. The prepared composites showed high efficiency for the inactivation of Escherichia coli (E. coli) bacteria under visible light and in dark media with different catalyst amounts of 12 and 24 mg, respectively. In less than 30 min, AgI/TiO2, prepared by the combination of cationic surfactant and PVPI2, disinfected 1 × 10(7) colony-forming units of E. coli completely. However,... 

A chemoselective synthesis of tetraketone and xanthene derivatives, by means of tandem Knoevenagel condensation and Michael addition in choline chloride-based deep eutectic solvents (DESs), is presented. The reaction of readily available aldehydes and active methylene compounds in malonic acid- and ZnCl2-based DES gives various xanthenes derivatives with good to excellent yields under mild reaction conditions. On the other hand, tetraketones were synthesized in almost quantitative yields by simple condensation of an aldehyde and active methylene compounds in milder deep eutectic solvents of urea and SnCl2. In addition, the reaction of other types of choline chloride-based DES leads to a... 

Sweeping gas membrane distillation process was studied using flat sheet hydrophobic PTFE membrane. The effects of operating parameters, including feed temperature, feed flow rate, sweeping gas flow rate, and feed concentration on the permeate flux, were determined. The feed temperature significantly influenced the permeate flux. Increasing the feed temperature increased the permeate flux. The increase of feed concentration caused to reduce the permeate flux due to the increase of concentration polarization effect and reduction of vapor pressure difference. Sweeping gas flow rate led to increase the permeate flux due to reduction of vapor pressure in the permeate side. Higher air flow rate... 

An effective approach for the synthesis of 2-(alkylthio)thiazol-4(5H)-ones from alkyl dithiocarbamates and chloroacetyl chloride in the presence of NaHCO3 has been developed. Good to excellent yields of products, simple reaction conditions and general applicability are the most important advantages of this protocol  

The current study investigates the effect of polyacrylonitrile (PAN) addition on morphology and antifouling properties of poly(vinyl chloride) (PVC) asymmetric flat ultrafiltration (UF) membranes. The membranes are prepared via phase inversion method induced by immersion precipitation at different PVC/PAN blending ratio up to 40 wt% PAN. Also, membranes with blending ratio of PVC/ PAN:70/30, which showed the highest water flux and flux recovery ratio, were used for membrane preparation with 4 wt% of Polyethylene glycol (PEG) addition in four different molecular weight, 600 Da, 1,000 Da, 6,000 Da and 20,000 Da, which was used as pore former and hydrophilic polymeric additive. The performance... 

Tridentate Schiff-base ligands derived from condensation of 3-formyl-4-hydroxybenzyl-triphenylphosphonium chloride with glycine, L-alanine, L-valine, L-leucine and L-phenylalanine in the presence of Zn(OAc)2·2H2O form five new water-soluble Zn(II) complexes, which were characterized by elemental analyses, IR, electronic absorption and 1H, 13C NMR spectroscopies. In the IR spectra of the complexes, the difference between the asymmetric and the symmetric carboxylate stretching frequencies is larger than ∼210 cm-1, which implies that the carboxylate groups are monodentate. UV-Vis electronic absorption studies show that Zn(II) functions as a trap for the Schiff-base intermediate. Schiff-base... 

Oximes were oxidized to the corresponding carbonyl compounds in good to high yields by environmentally friendly and green oxidant, H2O2 catalyzed by montmorillonite K-10 supported cobalt(II) chloride. © 2007 Ali Ezabadi  

In copper electrorefining process, some additives are added to the electrolyte to improve the morphology of cathode deposits as well as the quality of products. In the present investigation, the effects of thiourea, glue and chloride ions (as additives) on the passivation of industrial copper anodes under high current densities have been reported. Experiments were conducted at 65 °C; using a synthetic electrolyte containing 40 g/l Cu2+ and 160 g/l H2SO4. Results obtained from chronopotentiometry experiments showed that increasing the concentration of chloride ion leads to increase in passivation time. The results also indicated that from a certain level on, namely 2 ppm, the increase in... 

Here in this research, a modified interface between the electron transport layer (ETL) and the perovskite layer in a perovskite solar cell (PSC) is provided by adding the ammonium chloride (NH4Cl) to the tin oxide (SnO2) as the modified ETL of a planar structure as follows: fluorine-doped tin oxide (FTO)/NH4Cl-SnO2/Mixed cation perovskite/Copper indium disulfide (CIS)/Gold (Au). The effects of NH4Cl on ETL are investigated in different amounts from 0.003 to 0.02 M and the best results were obtained in the amount of 0.013 M. The best NH4Cl-SnO2 ETL could increase the power conversion efficiency (PCE) of fabricated planar PSC by 16.79% with open-circuit voltage (Voc) of 1.15 V and negligible... 

This study focuses on a forward looking approach in which deep eutectic solvents (DESs), a new class of designer solvents, were impregnated into micro porous polyvinylidene fluoride (PVDF) membrane for the separation of CO2 from CH4. Three types of DESs were prepared by mixing and heating of hydrogen bond acceptor (choline chloride) with either malic acid, tartaric acid or oxalic acid as hydrogen bond donor. The Fourier transform infrared spectroscopy confirmed the hydrogen bond interactions in the resulting DES. Thermal gravimetric analysis (TGA) was used to evaluate the thermal stability of the prepared membranes. The DES based supported liquid membranes were investigated systematically to... 

The authors regret that there were minor errors in the labels of the XRD patterns of cement and micro-silica presented in Figs. 1 and 2, which have been corrected in the figures included here. In addition, due to concerns over the reliability of the XRD pattern of pumice shown in Fig. 9, as caused by a low signal count, the authors have re-analyzed the pumice and the updated XRD pattern has been included here. It is worth noting that these changes do not affect any of the conclusions. The authors would like to apologise for any inconvenience caused. © 2021  

Here in this research, a modified interface between the electron transport layer (ETL) and the perovskite layer in a perovskite solar cell (PSC) is provided by adding the ammonium chloride (NH4Cl) to the tin oxide (SnO2) as the modified ETL of a planar structure as follows: fluorine-doped tin oxide (FTO)/NH4Cl-SnO2/Mixed cation perovskite/Copper indium disulfide (CIS)/Gold (Au). The effects of NH4Cl on ETL are investigated in different amounts from 0.003 to 0.02 M and the best results were obtained in the amount of 0.013 M. The best NH4Cl-SnO2 ETL could increase the power conversion efficiency (PCE) of fabricated planar PSC by 16.79% with open-circuit voltage (Voc) of 1.15 V and negligible... 

Aliphatic and aromatic amines undergo smooth nucleophilic addition to α,β-unsaturated compounds in the presence of a catalytic amount of silica-supported aluminum chloride at 60°C and under solvent-free conditions to produce the corresponding β-amino compounds in excellent yields. This method is simple and convenient and works efficiently under mild conditions. This catalyst can used again without losing its activity three times. Copyright © Taylor & Francis Group, LLC  

An ecofriendly one-pot multicomponent reaction of 1,3-dicarbonyl compounds, aldehydes, and malononitrile was carried out in a different deep eutectic solvent (DES) based on choline chloride, to synthesize highly functionalized benzopyran and pyran derivatives under catalyst-free conditions. The results showed that urea:choline chloride based DES is the best solvent and is successfully applicable to a wide range of aldehydes, active methylene compounds with high yields (75-95%) and short reaction times (1-4 h)  

A new one-pot synthesis of hitherto unknown polyheterocyclic systems via tandem C-alkylation and intramolecular O-alkylation of 4-hydroxycoumarin or 4-hydroxypyran-2-one with quinolinium salts in excellent yields (71-89%) is reported. The present approach provides a powerful route into polycyclic structures containing nitrogen and oxygen related to alkaloids  

This research studied the use of constructed wetlands (CWs) to reduce water salinity. For this purpose, three halophytic species of the Chenopodiaceae family (Salicornia europaea, Salsola crassa, and Bienertia cycloptera) that are resistant to saline conditions were planted in the CWs, and experiments were conducted at three different salinity levels [electrical conductivity (EC)~2, 6, 10 dS/m]. EC and concentrations of calcium (Ca), magnesium (Mg), sodium (Na), and chlorine (Cl) were measured before and after phytoremediation with a retention time of 1 week. The results suggested that these plants were able to grow well and complete their life cycles at all the salinity levels within this... 

A semi-interpenetrating polymer network (semi-IPN) hydrogel based on kappa-carrageenan (κC) and poly (vinylsulfonic acid, sodium salt) (PVSA) was prepared by graft copolymerization of acrylamide (AAm) using methylenebisacrylamide (MBA) as a crosslinking agent and ammonium persulfate (APS) as an initiator. FTIR spectroscopy was used for confirming the structure of the final product. It was found that the chemical composition of the Semi-IPN hydrogel is equal to the initial homopolymers and monomer feed compositions. The swelling capacity of the hydrogel was shown to be affected by the MBA, APS, and AAm concentration as well as κC/PVSA weight ratio. The swelling behavior of the hydrogel was... 

A combination of silica sulfuric acid and potassium chlorate or oxone® and silica chloride in the presence of wet SiO2 was used as an effective oxidizing agent for the oxidation of urazoles and bis-urazoles to their corresponding triazolinediones under mild and heterogeneous conditions with moderate to excellent yields. © 2006 Elsevier B.V. All rights reserved