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Analysis of Preservative Capacity for Contemporary Iranian Shampoos 当代伊朗香波的保鲜性分析
Advanced Journal of Chemistry-Section A Pub Date : 2019-01-01 DOI: 10.29088/SAMI/AJCA.2019.2.4556
M. Miranzadeh, M. Kassaee, L. Sadeghi
{"title":"Analysis of Preservative Capacity for Contemporary Iranian Shampoos","authors":"M. Miranzadeh, M. Kassaee, L. Sadeghi","doi":"10.29088/SAMI/AJCA.2019.2.4556","DOIUrl":"https://doi.org/10.29088/SAMI/AJCA.2019.2.4556","url":null,"abstract":"Preservative capacity is measured for seventeen currently accessible Iranian made shampoo products. Upon purchase, bacterial counts show no trace of any microbial contamination. The shampoo bottles are distributed to seventeen female graduate students, residing at the time in different dormitories of Tarbiat Modares University (TMU). After 40 days, the allocated bottles are returned and their bacterial counts repeated, under the same conditions. To our surprise, no trace of any microbial contamination is observed. Three possibilities are considered. 1) The factory employed preservative(s) act very efficiently. 2) The shampoo component(s) are themselves bactericidal. 3) Existence of sanitary conditions and the absence of any microbial contaminants at TMU! Evidently, the third possibility is ruled out. The second choice is also discarded, because practically no significant antimicrobial activity is demonstrated by any of the four main ingredients of the shampoos including sodium lauryl ether sulfate (SLES), betaine, coconut fatty acid, and glycerin. Hence, the most likely possibility is the first one, since upon deliberate contamination of the seventeen brands; the factory employed preservatives [5-chloro-2-methyl-4-isothiazolin-3-one and 2-methyl-4-isothiazolin-3-one (KATHON CG)] prove highly bactericidal against four major contaminants: Escherichia coli, Staphylococcus aureus, Pseudomonas aeruginosa, and the methicillin-resistant Staphylococcus aureus (MRSA).","PeriodicalId":7207,"journal":{"name":"Advanced Journal of Chemistry-Section A","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2019-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"77285125","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
引用次数: 1
PHYSICO-CHEMICAL PARAMETERS OF INDUSTRIAL EFFLENTS FROM A BREWERY INDUSTRY IN IMO STATE, NIGERIA. 尼日利亚伊莫州啤酒厂工业废水的物理化学参数。
Advanced Journal of Chemistry-Section A Pub Date : 2018-11-01 DOI: 10.29088/SAMI/AJCA.2018.1.6678
K. Iwuozor, E. Gold
{"title":"PHYSICO-CHEMICAL PARAMETERS OF INDUSTRIAL EFFLENTS FROM A BREWERY INDUSTRY IN IMO STATE, NIGERIA.","authors":"K. Iwuozor, E. Gold","doi":"10.29088/SAMI/AJCA.2018.1.6678","DOIUrl":"https://doi.org/10.29088/SAMI/AJCA.2018.1.6678","url":null,"abstract":"This work examined some physicochemical parameters of effluents from a Brewery Industry in Imo state. This company discharged effluents in non-compliance with the Nigerian National Regulations as confirmed from the Biochemical Oxygen Demand (BOD), Chemical Oxygen Demand (COD), Electrical Conductivity (EC), Nitrogen, and Turbidity results. The heavy metals have concentrations that were within WHO/FEPA limits. These confirmed results posed health risks to several rural communities which rely on the receiving water bodies as their primary source of domestic water. There is need for the intervention of appropriate regulatory agencies to ensure production of high quality treated final effluents. This scenario is typical of most industries in developing nations where enforcement of environmental regulations are deficient. To avoid pollution, regulatory authorities should closely monitor compliance by industries.","PeriodicalId":7207,"journal":{"name":"Advanced Journal of Chemistry-Section A","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2018-11-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"87944496","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
引用次数: 2
Enhancing the performance of polysulfone ultrafiltration membranes by mixing with polyacrylic acid for canal water treatment 聚砜超滤膜与聚丙烯酸混合处理运河水的研究
Advanced Journal of Chemistry-Section A Pub Date : 2018-11-01 DOI: 10.29088/SAMI/AJCA.2018.1.8695
M. Aal, Abdelmonim Ahmed, H. H. A. Rahman, S. Kandil
{"title":"Enhancing the performance of polysulfone ultrafiltration membranes by mixing with polyacrylic acid for canal water treatment","authors":"M. Aal, Abdelmonim Ahmed, H. H. A. Rahman, S. Kandil","doi":"10.29088/SAMI/AJCA.2018.1.8695","DOIUrl":"https://doi.org/10.29088/SAMI/AJCA.2018.1.8695","url":null,"abstract":"We developed some Ultrafiltration (UF)  membranes based on polysulfone (PSF) and poly acrylic acid (PAA) mixture. The Ultrafiltration membraneswere prepared by the phase inversion technique using Dimethylformamide (DMF) as a solvent. Immobilization of PAA in PSF matrix was confirmed by Fourier transform infrared spectroscopy (FTIR). The membranes have an asymmetric structure, as revealed by scanning electron microscopy (SEM). Natural water from Mahmoudia canal (a subdivision of the Nile River) is used as feed water. The permeate flux reached 120.0 l/m2.hr. The hydrophilicity measured by contact angle was enhanced by the addition of PAA to reach 66.00. The prepared membranes showed good tensile strength that reached 7.2 MPa. Turbidity rejection and dissolved organic carbon (DOC) rejection reached 98.4% and 65 %, respectively. These performances obtained at ambient operating conditions, make the fabricated membranes attractive for canal water treatment.","PeriodicalId":7207,"journal":{"name":"Advanced Journal of Chemistry-Section A","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2018-11-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"87573895","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
引用次数: 2
Simultaneous identification and determination of three different classes of pesticides in Tehran drinking water by HPLC/UV technique 高效液相色谱/紫外分光光度法测定德黑兰饮用水中3种农药
Advanced Journal of Chemistry-Section A Pub Date : 2018-11-01 DOI: 10.29088/sami/AJCA.2018.1.7985
Mahtab Baghban, A. Rezaian, E. Hashemi
{"title":"Simultaneous identification and determination of three different classes of pesticides in Tehran drinking water by HPLC/UV technique","authors":"Mahtab Baghban, A. Rezaian, E. Hashemi","doi":"10.29088/sami/AJCA.2018.1.7985","DOIUrl":"https://doi.org/10.29088/sami/AJCA.2018.1.7985","url":null,"abstract":"An efficient sample extraction using solid-phase extraction coupled with liquid-chromatography was studied for the analyses of three different types and chemical group pesticides from drinking water. The extraction was performed using a Waters Sep-Pak C-18 cartridge. A validation of the method was performed. Linearity (0.005-1000, 0.01-1000, 4-1000, 10.5-1000 and 9.48-1000 µg.L-1 for Simazine, Atrazine, Isoproturon, Metolachlor and Chlorotoluron respectively range), within-day precisions ranged from 4.8 to 6.7% and the between day precisions ranged of 7.8-13.3 % based on the peak areas for five replicates, limits of detection (0.001-2.846 µg.L-1) were calculated. The preconcentration factors (PFs) were obtained under the optimum conditions (15.04-22.53). The information obtained from the method validation has been used to estimate for the determination of pesticides at trace levels in water samples which collected from water treatment plants of Tehran, the capital of Iran.","PeriodicalId":7207,"journal":{"name":"Advanced Journal of Chemistry-Section A","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2018-11-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"88273950","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
引用次数: 0
DFT calculations of the neighboring groups effects on cheletropic reaction of 2,5-Dihydrothiophene sulfone 邻基对2,5-二氢噻吩砜亲电反应影响的DFT计算
Advanced Journal of Chemistry-Section A Pub Date : 2018-11-01 DOI: 10.29088/SAMI/AJCA.2018.1.117126
Z. Javanshir, S. Jameh-bozorghi, Parasto Peyki
{"title":"DFT calculations of the neighboring groups effects on cheletropic reaction of 2,5-Dihydrothiophene sulfone","authors":"Z. Javanshir, S. Jameh-bozorghi, Parasto Peyki","doi":"10.29088/SAMI/AJCA.2018.1.117126","DOIUrl":"https://doi.org/10.29088/SAMI/AJCA.2018.1.117126","url":null,"abstract":"In this research DFT calculations were used to investigate the neighboring effects on cheletropic reaction of 2,5-Dihydrothiophene sulfone(1). Structural properties and stereoelectronic behavior in the activation energy and enthalpy of cheletropic reaction was performed for 2,5-Dihydrothiophene sulfone where substitutions of CF3; CCl3 and CBr3 that were placed on Sulfolen were investigated by using DFT-B3LYP/6-311+G** level of theory. The Results of calculations using B3LYP, HF and MP2 [basic 6-311+G**] showed that the trend of electronic effects on the cis and trans state is different. Reaction rate and activation energy in cis compounds showed that increasing electronegativity and decreasing the band length reduced the reaction speed. Trend of reaction rate and activation energy in Trans compounds showed that in cheletropic reaction rate and activation energy not only electronic effects but also the Steric effects play a main role. DFT/B3LYP/6-311+G** calculation results also confirm these results. In cis compounds, 2,5- three Floro metyl Sulfolen(2) has the highest activation energy about (12.25 kcal/mol) and the lowest rate of reaction. In trans compounds, Trans-2,5- three chloro metyl Sulfolen(7) has the highest activation energy about (12.99 kcal/mol) and the lowest rate of reaction.","PeriodicalId":7207,"journal":{"name":"Advanced Journal of Chemistry-Section A","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2018-11-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"88616199","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
引用次数: 3
Investigating effect of cerium (IV) sulfate tetrahydrate as reusable and heterogeneous catalyst for the one‐pot multicomponent synthesis of polyhydroquinolines 四水合硫酸铈作为可重复使用的多相催化剂在一锅多组分合成多对苯二酚中的作用研究
Advanced Journal of Chemistry-Section A Pub Date : 2018-11-01 DOI: 10.29088/SAMI/AJCA.2018.1.96104
E. Kazemi, A. Davoodnia, A. Nakhaei, S. Basafa, N. Tavakoli-Hoseini
{"title":"Investigating effect of cerium (IV) sulfate tetrahydrate as reusable and heterogeneous catalyst for the one‐pot multicomponent synthesis of polyhydroquinolines","authors":"E. Kazemi, A. Davoodnia, A. Nakhaei, S. Basafa, N. Tavakoli-Hoseini","doi":"10.29088/SAMI/AJCA.2018.1.96104","DOIUrl":"https://doi.org/10.29088/SAMI/AJCA.2018.1.96104","url":null,"abstract":"Cerium (IV) sulfate tetrahydrate, Ce(SO4)2.4H2O used as a new inorganic solid acidic catalyst for the synthesis of polyhydroquinoline derivatives via four-component Hantzsch reaction of aromatic/aliphatic aldehydes, 5,5-dimethylcyclohexane-1,3-dione (dimedone), ethyl acetoacetate and ammonium acetate under solvent-free conditions at 120 °C. This method has the advantages of high yields (88-97 %), clean reaction, simple methodology, and short reaction time (15-25 min). However, the aromatic aldehydes whether electron donating or electron withdrawing showed simple transformation with the excellent yields than the other aliphatic. Furthermore, the catalyst is inexpensive and readily available and can be recovered conveniently and reused efficiently without considerable decrease in its catalytic activity.","PeriodicalId":7207,"journal":{"name":"Advanced Journal of Chemistry-Section A","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2018-11-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"90720983","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
引用次数: 4
Reviewing of metalloporphyrins as novel catalysts for synthesis of conducting and water-soluble polymers 金属卟啉作为新型导电高分子和水溶性高分子催化剂的研究进展
Advanced Journal of Chemistry-Section A Pub Date : 2018-11-01 DOI: 10.29088/SAMI/AJCA.2018.1.105116
Zahra Zamiraei, M. Golzar, Hoda Hamidi
{"title":"Reviewing of metalloporphyrins as novel catalysts for synthesis of conducting and water-soluble polymers","authors":"Zahra Zamiraei, M. Golzar, Hoda Hamidi","doi":"10.29088/SAMI/AJCA.2018.1.105116","DOIUrl":"https://doi.org/10.29088/SAMI/AJCA.2018.1.105116","url":null,"abstract":"Porphyrins are a group of heterocyclic macrocycle organic compounds, composed of four modified pyrrole subunits interconnected at their α carbon atoms via methine bridges (=CH−). Porphyrins have attracted much attention because of their unique structures and a wide spectrum of very useful physicochemical and biological properties, such as anion binding, stabilization of metal ions with unusual oxidation states, electron transfer, and construction of peculiar supramolecular assemblies. The synthesis of electroactive and water-soluble polymers were accomplished with water-soluble metal(III) porphyrins in the presence of a template. The polymerization by matelloporphyrin is simple (one-step), chemically mild, and environmentally benign and requires minimal separation. This approach provides a distinct advantage over similar reactions employing native enzymes due to higher stability and lower price of the catalysts.","PeriodicalId":7207,"journal":{"name":"Advanced Journal of Chemistry-Section A","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2018-11-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"82197958","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
引用次数: 1
Heat transfer and fluid flow analysis of a novel micro-miniature cryocooler model 一种新型微型制冷机模型的传热与流体流动分析
Advanced Journal of Chemistry-Section A Pub Date : 2018-09-01 DOI: 10.29088/SAMI/AJCA.2018.4.3238
Hussayn Bakhshy, S. Rohani, P. Heydari, R. Asadi
{"title":"Heat transfer and fluid flow analysis of a novel micro-miniature cryocooler model","authors":"Hussayn Bakhshy, S. Rohani, P. Heydari, R. Asadi","doi":"10.29088/SAMI/AJCA.2018.4.3238","DOIUrl":"https://doi.org/10.29088/SAMI/AJCA.2018.4.3238","url":null,"abstract":"In the current study, a new model for micro-scale cooling systems is presented. The small-scale refrigerator is modeled by engraving channels and a micro nozzle on the sides of a rectangular glass. The system has the capability to reduce the temperature from 300K to 80 in 5 seconds using nitrogen as the working fluid. The model consists of three elements, heat exchanger, nozzle and expansion tank and all the parts of the cooling system is stationary. For this novel model, pressure drop through the channels and nozzle sections is presented and by using these information, temperature drop through the nozzle is obtained regarding the high Mach number at the throat of the convergence-divergence micro-nozzle. Due to the characteristics of this in-plane micro-nozzle, the heat exchange is modeled through the time in the glass, and temperature of the cooling system is reported.","PeriodicalId":7207,"journal":{"name":"Advanced Journal of Chemistry-Section A","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2018-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"75918697","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
引用次数: 3
Caro's Acid-Silica Gel Catalyzed Regioselective Ring Opening of Epoxides with Indoles and Imidazoles under Solvent-Free Conditions 无溶剂条件下Caro's酸-硅胶催化吲哚和咪唑环氧化合物的区域选择性开环
Advanced Journal of Chemistry-Section A Pub Date : 2018-09-01 DOI: 10.29088/SAMI/AJCA.2018.1.16
M. Heravi, Hoda Hamidi, N. Karimi, Akram Amouchi
{"title":"Caro's Acid-Silica Gel Catalyzed Regioselective Ring Opening of Epoxides with Indoles and Imidazoles under Solvent-Free Conditions","authors":"M. Heravi, Hoda Hamidi, N. Karimi, Akram Amouchi","doi":"10.29088/SAMI/AJCA.2018.1.16","DOIUrl":"https://doi.org/10.29088/SAMI/AJCA.2018.1.16","url":null,"abstract":"An efficient and facile procedure has been developed for the ring opening of epoxides with nitrogen heterocycles such as indole and imidazole in the presence of Caro's acid-silica gel (CA-SiO2) as catalyst in solventless system. The reactions were administered underneath Solvent-free conditions. The current methodology offers many benefits like good yields, easy procedure, simple work-up and ecofriendly reaction condition. The catalyst is well ready, stable and economical underneath the reaction conditions.","PeriodicalId":7207,"journal":{"name":"Advanced Journal of Chemistry-Section A","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2018-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"87641039","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
引用次数: 3
Synthesis and chemical modification of maleic anhydride copolymers with 2-amino ethyl benzoate groups 2-氨基苯甲酸乙酯基马来酸酐共聚物的合成及化学改性
Advanced Journal of Chemistry-Section A Pub Date : 2018-09-01 DOI: 10.29088/SAMI/AJCA.2018.6.5665
M. H. Nasirtabrizi, S. J. Mousavi
{"title":"Synthesis and chemical modification of maleic anhydride copolymers with 2-amino ethyl benzoate groups","authors":"M. H. Nasirtabrizi, S. J. Mousavi","doi":"10.29088/SAMI/AJCA.2018.6.5665","DOIUrl":"https://doi.org/10.29088/SAMI/AJCA.2018.6.5665","url":null,"abstract":"Maleic anhydride (MAN) copolymers with methyl methacrylate, ethyl methacrylate, methyl acrylate, ethyl acrylate, and butyl acrylate monomers at 1:3 mole ratios were synthesized by free radical polymerization in the presence of azobis(isobutyronitrile) as initiator and dry ethyl acetate as solvent. Copolymer compositions were obtained using related proton nuclear magnetic resonance (1HNMR) spectra, and the polydispersity of the copolymers was determined by gel permeation chromatography. Then, a solution of 2-amino ethyl benzoate salt as a nucleophilic reagent reacted through the ring opening of anhydride groups in copolymers resulting to modified copolymers Iab to Vab. All the prepared polymers were characterized by Fourier transform infrared and1H NMR spectroscopic techniques. The glass transition temperature (Tg) of all copolymers before and after modification was determined by dynamic mechanical thermal analysis (DMTA). It was shown that chemical modification of MAN copolymers with 2-amino ethyl benzoate substituents as side chains decreased the free volume of the polymers, and therefore, the rigidity and Tg are increased.","PeriodicalId":7207,"journal":{"name":"Advanced Journal of Chemistry-Section A","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2018-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"76985127","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
引用次数: 2
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