Journal of the Association of Arab Universities for Basic and Applied Sciences最新文献_第10页

Synthesis and spectral, antibacterial, molecular studies of biologically active organosilicon(IV) complexes 生物活性有机硅(IV)配合物的合成及光谱、抗菌、分子研究

Journal of the Association of Arab Universities for Basic and Applied Sciences Pub Date : 2017-06-01 DOI: 10.1016/j.jaubas.2016.05.003

Har Lal Singh, J.B. Singh, Sunita Bhanuka

{"title":"Synthesis and spectral, antibacterial, molecular studies of biologically active organosilicon(IV) complexes","authors":"Har Lal Singh, J.B. Singh, Sunita Bhanuka","doi":"10.1016/j.jaubas.2016.05.003","DOIUrl":"10.1016/j.jaubas.2016.05.003","url":null,"abstract":"<div><p>A series of new organosilicon(IV) complexes have general formulae R<sub>3</sub>SiL and RSiLOEt with Schiff bases (R=Me and Ph). The Schiff bases (LH) have been derived from the condensation of (2-hydroxyphenyl)(pyrrolidin-1-yl)methanone with semicarbazide, thiosemicarbazide, and phenylthiosemicarbazide, respectively. The compounds have been characterized by the elemental analysis, molar conductance, and spectral (UV, IR, <sup>1</sup>H, <sup>13</sup>C, and <sup>29</sup>Si NMR) studies. These studies showed that the ligands coordinate with the silicon atom in a tridentate manner through phenolic oxygen, azomethine nitrogen and thiolic sulfur. Further applying experimental spectroscopic techniques, theoretical data calculated using density functional theory by B3LYP/6.31+g(d,p) has also been used for structural determination. The resulting complexes have been proposed to have trigonal bipyramidal and distorted octahedral geometries. Few representative Schiff base and their silicon complexes have been screened for their in vitro antibacterial activity against Gram-positive and Gram-negative bacteria. The minimum inhibitory concentration (MIC) of selected compounds was determined. The screening results show that organosilicon(IV) complexes have better antibacterial activity than the free ligands.</p></div>","PeriodicalId":17232,"journal":{"name":"Journal of the Association of Arab Universities for Basic and Applied Sciences","volume":"23 ","pages":"Pages 1-9"},"PeriodicalIF":0.0,"publicationDate":"2017-06-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1016/j.jaubas.2016.05.003","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"80590547","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 10

Quintic spline collocation method for fractional boundary value problems 分数阶边值问题的五次样条配点法

Journal of the Association of Arab Universities for Basic and Applied Sciences Pub Date : 2017-06-01 DOI: 10.1016/j.jaubas.2016.03.003

Ghazala Akram, Hira Tariq

引用次数: 8

Nonlocal symmetries and interaction solutions for the KdV-type K(3,2) equation kdv型K(3,2)方程的非局部对称性和相互作用解

Journal of the Association of Arab Universities for Basic and Applied Sciences Pub Date : 2017-06-01 DOI: 10.1016/j.jaubas.2016.07.003

Hengchun Hu , Yujuan Li

引用次数: 0

Solution of mixed integral equation in position and time using spectral relationships 利用谱关系求解位置和时间的混合积分方程

Journal of the Association of Arab Universities for Basic and Applied Sciences Pub Date : 2017-06-01 DOI: 10.1016/j.jaubas.2016.05.001

M.A. Abdou, M. Basseem

引用次数: 7

2-Amino-4-(2,4-dihydroxyphenyl) quinoline-3-carbonitrile as sustainable corrosion inhibitor for SAE 1006 steel in 1 M HCl: Electrochemical and surface investigation 2-氨基-4-(2,4-二羟基苯基)喹啉-3-碳腈作为SAE 1006钢在1m HCl中的缓蚀剂:电化学和表面研究

Journal of the Association of Arab Universities for Basic and Applied Sciences Pub Date : 2017-06-01 DOI: 10.1016/j.jaubas.2016.03.002

Chandrabhan Verma, M.A. Quraishi

引用次数: 24

Approximate solutions for solving the Klein–Gordon and sine-Gordon equations Klein-Gordon方程和sin - gordon方程的近似解

Journal of the Association of Arab Universities for Basic and Applied Sciences Pub Date : 2017-02-01 DOI: 10.1016/j.jaubas.2015.10.003

Majeed A. Yousif , Bewar A. Mahmood

引用次数: 21

Shapeable maximum-power point-tracking algorithm to improve the stability of the output behavior of a thermoelectric-solar hybrid energy-harvesting system 提高热电-太阳能混合能量收集系统输出行为稳定性的可成形最大功率点跟踪算法

Journal of the Association of Arab Universities for Basic and Applied Sciences Pub Date : 2017-02-01 DOI: 10.1016/j.jaubas.2016.01.002

A. M. Yusop, R. Mohamed, A. Ayob, A. Mohamed

引用次数: 5

Stability and boundedness in delay system of differential equations of third order 三阶微分方程时滞系统的稳定性和有界性

Journal of the Association of Arab Universities for Basic and Applied Sciences Pub Date : 2017-02-01 DOI: 10.1016/j.jaubas.2016.01.004

Cemil Tunc

引用次数: 11

Global warming awareness among the University of Bahrain science students 巴林大学理科学生的全球变暖意识

Journal of the Association of Arab Universities for Basic and Applied Sciences Pub Date : 2017-02-01 DOI: 10.1016/j.jaubas.2016.02.002

Afnan Mahmood Freije, Tahani Hussain, Eman Ali Salman

{"title":"Global warming awareness among the University of Bahrain science students","authors":"Afnan Mahmood Freije, Tahani Hussain, Eman Ali Salman","doi":"10.1016/j.jaubas.2016.02.002","DOIUrl":"10.1016/j.jaubas.2016.02.002","url":null,"abstract":"<div><p>This study was designed to investigate the awareness regarding global warming among the College of Science students at University of Bahrain. A total of 143 science students were examined using a questionnaire that covered three aspects of global warming including causes, impacts, and solutions. The study included 51, 28, 40 and 24 students from the departments of biology, chemistry, mathematics, and physics respectively. The results have shown that 55±10.18% of all students examined answered the questions correctly of which 51±10.28% were in the first year, while 60±7.4% were in their fourth year indicating a direct positive impact of university education. A significant dependence (<em>p</em>  <!-->0.05) was recorded between first and fourth year students’ answers. The results have shown that fourth year biology students were the most knowledgeable, a fact that can be attributed to their academic curriculum. Therefore, the study has recommended integrating environmental concepts into the university curriculum for all students irrespective of their academic specialization in order to increase the environmental awareness.</p></div>","PeriodicalId":17232,"journal":{"name":"Journal of the Association of Arab Universities for Basic and Applied Sciences","volume":"22 ","pages":"Pages 9-16"},"PeriodicalIF":0.0,"publicationDate":"2017-02-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1016/j.jaubas.2016.02.002","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"79663637","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 59

Adsorption, leaching and phytotoxicity of some herbicides as single and mixtures to some crops 某些除草剂单剂和混剂对某些作物的吸附、淋滤和植物毒性

Journal of the Association of Arab Universities for Basic and Applied Sciences Pub Date : 2017-02-01 DOI: 10.1016/j.jaubas.2016.01.001

Yasser El-Nahhal, Nisreen Hamdona

{"title":"Adsorption, leaching and phytotoxicity of some herbicides as single and mixtures to some crops","authors":"Yasser El-Nahhal, Nisreen Hamdona","doi":"10.1016/j.jaubas.2016.01.001","DOIUrl":"10.1016/j.jaubas.2016.01.001","url":null,"abstract":"<div><p>The study investigated adsorption, leaching potential, and phytotoxicity of alachlor, bromacil, and diuron on melon, Molokhia, and wheat in Gaza strip. Plant height was used to estimate growth inhibition (phytotoxicity). Growth inhibition data were regressed versus concentrations of corresponding herbicide to estimate EC<sub>50</sub> value. The lowest EC<sub>50</sub> value indicates the highest phytotoxicity. Adsorption results indicated that alachlor, bromacil and diuron have different shapes. Leaching potentials indicated that alachlor totally disappeared from the top 5cm and accumulated at a deeper depth whereas bromacil and diuron accumulated in the top 8cm of soil layer with a decreasing intensity at deeper depth. Phytotoxicity tests showed that diuron has the lowest EC<sub>50</sub> values on melon (1.64) and Molokhia (0.15) whereas bromacil has the lowest one on wheat (0.08), values are in (mg/kg soil). Results of binary mixtures showed that the mixture contained alachlor and diuron was the most toxic to melon, whereas mixture contained alachlor and bromacil was the most toxic to Molokhia and wheat. Tertiary mixture (alachlor+bromacil+diuron) was more toxic on Molokhia than melon and wheat, EC<sub>50</sub> values were 3.02, 32.174, and 633.9TU/kg soil on Molokhia, melon, and wheat respectively. An interesting outcome of the study is that Molokhia was the most sensitive plant and binary mixtures showed synergistic phytotoxicity.</p></div>","PeriodicalId":17232,"journal":{"name":"Journal of the Association of Arab Universities for Basic and Applied Sciences","volume":"22 ","pages":"Pages 17-25"},"PeriodicalIF":0.0,"publicationDate":"2017-02-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1016/j.jaubas.2016.01.001","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"89583165","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 37