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51.
Using Caenorhabditis elegans to probe toxicity of 1-alkyl-3-methylimidazolium chloride based ionic liquids 总被引:2,自引:0,他引:2
Swatloski RP Holbrey JD Memon SB Caldwell GA Caldwell KA Rogers RD 《Chemical communications (Cambridge, England)》2004,(6):668-669
Ionic liquids are gaining attention as new solvents within the green chemistry community; however this attention has quickly outstripped current environmental and toxicological data available. In the present communication, we establish the use of Caenorhabditis elegans as a model organism for inexpensively and quickly exploring toxicological effects of 1-alkyl-3-methylimidazolium chloride ionic liquids. 相似文献
52.
Memon Shebaz A. Jaiswal Meet S. Jain Yuvan Acharya Vaibhav Upadhyay Darshit S. 《Journal of Thermal Analysis and Calorimetry》2020,141(6):2253-2263
Journal of Thermal Analysis and Calorimetry - The biomass has been the choice of the heat source for cooking purposes since ancient times. The inefficient combustion process in traditional... 相似文献
53.
Serkan Sayin Fatih Ozcan Shahabuddin Memon Mustafa Yilmaz 《Journal of inclusion phenomena and macrocyclic chemistry》2010,67(3-4):385-391
The article describes synthesis as well as the evaluation of sorption properties of new N-methylglucamine substituted calix[4]arene and its poly[(phenyl glycidyl ether)-co-formaldehyde] immobilized product. Firstly, 5,17-bis-[(N-methylglucamine)methyl]-25,26,27,28-tetrahydroxy-calix[4]arene (3) was synthesized by the treatment of calix[4]arene with a secondary amine N-methylglucamine and formaldehyde via Mannich reaction. The immobilization of 3 onto poly[(phenyl glycidyl ether)-co-formaldehyde] to form calixarene based polymer (4) was carried out under suitable reaction conditions via nucleophilic substitution reaction. All the new compounds were characterized by a combination of FT-IR, 1H-NMR spectroscopic and elemental analysis techniques. The sorption studies of 4 reveal that it is an excellent material for the removal of toxic oxoanions especially arsenate from aqueous environment. To understand the selectivity of 4, we also examined the retention of dichromate anions in the presence of Cl?, NO3 ? and SO4 2? anions at pH 1.5. 相似文献
54.
55.
Abdul Hafeez Laghari Shahabuddin Memon Aisha Nelofar Khalid Mohammed Khan 《Helvetica chimica acta》2012,95(9):1556-1560
A new ursene‐type triterpene, (3β)‐30‐norurs‐11‐en‐3‐ol ( 1 ), was isolated from the MeOH extract of the roots of Alhagi camelorum. Its structure was elucidated on the basis of extensive spectroscopic investigations by 1D‐ and 2D‐NMR studies. In addition, 1 was evaluated for antifungal activities. Its application on prepared cultures of two fungi, i.e., Aspergillus niger and Saccharomyces cerevisiae, showed noticeable antifungal activity, suggesting that 1 could be used as a new promising agent in antifungal drug formulations. 相似文献
56.
The present article describes an exploration regarding Hg(II) selective complexation behavior of 5,11,17,23-tetrakis[(N,N-dimethylamino)methyl]-25,26,27,28-tetrahydroxycalix[4]arene (4). The binding affinity of 4 toward selected transition metal ions such as Cd(II), Co(II), Cu(II), Hg(II), Ni(II), Pb(II) and Zn(II) have been investigated by UV-visible and fluorescence spectroscopies. From the results it has been noticed that 4 confers a pronounced preference for Hg(II) in complexation phenomenon even in the presence of other metal ions. The results of Job's plot analysis reveal 1:1 host-guest complex formation between Hg(II) and 4. The FT-IR spectroscopy also supports the complexation affinity of 4 for Hg(II). 相似文献
57.
Imam Bakhsh Solangi Shahabuddin Memon Najma Memon M. I. Bhanger 《高分子科学杂志,A辑:纯化学与应用化学》2013,50(12):1003-1008
The selective behavior of calix[n]arene ester derivatives in two-phase extraction systems using polarographic technique has been investigated. Calix[4]arene tetraester derivative shows remarkable Na+ over Pb2+ selectivity; whereas calix[6]arene hexaester derivative shows Pb2+ over Na+ selectivity. The interference of some selected cations (Na+, K+, Cu2+ and Mg2+) were also examined and no significant effect on the selectivity behavior as well as extraction ability of these ionophores was found except Na+. The study reveals for the first time that the calix[6]arene hexaester derivative is highly Pb2+ selective ionophore and can be employed in the field of sensor as well as separation science and technology. The work also highlights the usefulness of polarographic technique in trace metal determination. 相似文献
58.
Javeed Akhtar Naeema Khan Shahabuddin Memon Zaman Ashraf Ghulam Abbas M. Usman Anwar 《高分子科学杂志,A辑:纯化学与应用化学》2013,50(12):1627-1638
New substituted and unsubstituted phenol based mesogene series having an azo central linkage was synthesized by fixing phenol as rigid core unit with aromatic amine. The terminal –OH group was esterified successively by long alkyl chain acid chloride of variable length (n=2, 6, 11, 15, 17). All 25 synthesized compounds exhibit mesomorphism. The effect of side chain length and substituents on the stability of liquid crystals was studied. The study reveals that nitro substituent destabilizes nematic and smectic phases more than floro substituent. Furthermore, the transition temperature decreases as the length of side chain increases. 相似文献
59.
Summary Cu(II) Co(II) and Fe(II) in pharmaceutical preparations were determined using precolumn derivatization and solvent extraction
with 2-acetylpyridine-4-phenyl-3-thiosemicarbazone (APPT) as complexing reagent. Liquid chromatography (LC) was carried out
on a reversed phase C-18, column. The complexes were eluted isocratically with acetonitrile-water containing sodium acetate
and tetrabutyl ammonium bromide as ion-pairing agents. The results obtained were compared with those using atomic absorption. 相似文献
60.
Ali N. Siyal Saima Q. Memon Abdullah Akdoğan Aysen Hol Aslihan Arslan Kartal 《International journal of environmental analytical chemistry》2013,93(8):743-755
Expanded polystyrene (EPS) foam waste (white pollutant) was utilised for the synthesis of novel chelating resin i.e. EPS-N = N-α-Benzoin oxime (EPS-N = N-Box). The synthesised resin was characterised by FT-IR spectroscopy, elemental analysis, and thermogravimetric analysis. A selective method for the preconcentration of Pb(II) ions on EPS-N = N-Box resin packed in mini-column was developed. The sorbed Pb(II) ions were eluted with 5.0 mL of 2.0 mol L?1 HCl and determined by microsample injection system coupled flame atomic absorption spectrometry (MIS-FAAS). The average recovery of Pb(II) ions was achieved 95.5% at optimum parameters such as pH 7, resin amount 400 mg, flow rates 1.0 mL min?1 (of eluent) and3.0 mL min?1 (of sample solution). The total saturation capacity of the resin, limit of detection (LOD) and limit of quantification (LOQ) of Pb(II) ions were found to be 30 mg g?1, 0.033 μg L?1 and 0.107 μg L?1, respectively with preconcentration factor of 300. The accuracy, selectivity and validation of the method was checked by analysis of sea water (BCR-403), wastewater (BCR-715) and Tibet soil (NCS DC-78302) as certified reference materials (CRMs). The proposed method was applied successfully for the trace determination of Pb(II) ions in aqueous samples. 相似文献