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21.
Kumar VG Gokavarapu SD Rajeswari A Dhas TS Karthick V Kapadia Z Shrestha T Barathy IA Roy A Sinha S 《Colloids and surfaces. B, Biointerfaces》2011,87(1):159-163
A simple biological method for the synthesis of gold nanoparticles (AuNPs) using Cassia auriculata aqueous leaf extract has been carried out in the present study. The reduction of auric chloride led to the formation of AuNPs within 10 min at room temperature (28°C), suggesting a higher reaction rate than chemical methods involved in the synthesis. The size, shape and elemental analysis were carried out using X-ray diffraction, TEM, SEM-EDAX, FT-IR and visible absorption spectroscopy. Stable, triangular and spherical crystalline AuNPs with well-defined dimensions of average size of 15-25 nm were synthesized using C. auriculata. Effect of pH was also studied to check the stability of AuNPs. The main aim of the investigation is to synthesize AuNPs using antidiabetic potent medicinal plant. The stabilizing and reducing molecules of nanoparticles may promote anti-hyperglycemic if tested further. 相似文献
22.
Saqib Ali Syed Usman Ahmad Saira Shahzadi Sadiq‐ur‐Rehman Masood Parvez Muhammad Mazhar 《应用有机金属化学》2005,19(1):201-201
Me2Sn(S2CN(CH2)5)Cl contains five‐coordinated tin with a bidentate dithiocarbamate ligand spanning equatorial and axial positions in a distorted trigonal bipyramidal geometry. Copyright © 2005 John Wiley & Sons, Ltd. 相似文献
23.
Abstract (4-Methylpiperidine-dithiocarbamato-S,S′)triphenyltin(IV) derivative of 4-methyl-1-piperidine carbodithioic acid (4-MePCDTA) have been synthesized and characterized
by elemental, IR, multinuclear NMR (1H and 13C) and mass spectrometric studies. The crystal structure of the complex has been determined by X-ray single crystal analysis,
which shows unsymmetrical nature of the ligand towards coordination to tin. It crystallizes in monoclinic P21/c space group with the crystal cell parameters: a = 10.1863(10) ?, b = 21.200(2) ?, c = 11.7332(11) ?, β = 111.2020(10)°, Z = 4 and V = 2,362.2(4) ?3. The tin atom is coordinated to the two sulfur atoms of the dithiocarbamate ligand and three carbon atoms of the phenyl groups
are in distorted trigonal bipyramid geometry. This complex was tested for its antimicrobial activity against six different
plant and human pathogens. The screening results show that the complex exhibit higher antibacterial and antifungal activity
than the free ligand.
Index abstract
Synthesis, Spectroscopy, in vitro Biological Activity and X-Ray Structure of (4-Methylpiperidine-dithiocarbamato-S,S′)triphenyltin(IV)
Saira Shahzadi, Saqib Ali and Mohammmed Fettouhi
4-Methyl-1-piperidine carbodithioic acid behaves as anisobidentate ligand and chelates the tin atom by means of sulfur atoms
giving cis-trigonal bipyramid geometry around the tin atom.
Electronic supplementary material The online version of this article (doi:) contains supplementary material, which is available to authorized users. 相似文献
24.
Mehfooz Haroon Saeed Aamer Faisal Muhammad Larik Fayaz Ali Muqadar Urooj Khatoon Saira Channar Pervaiz Ali Ismail Hammad Bilquees Salma Rashid Sajid Shafique Shagufta Mirza Bushra Dilshad Erum Ahmad Fawad 《Research on Chemical Intermediates》2020,46(5):2437-2456
Research on Chemical Intermediates - Meldrum’s acid derivatives were facile synthesized by one-pot condensation process and characterized by NMR (1H, 13C, DEPT-90 and DEPT-135) and EI-MS. The... 相似文献
25.
Bakherad Mohammad Moosavi-Tekyeh Zainab Keivanloo Ali Gholizadeh Mostafa Toozandejani Zahra 《Research on Chemical Intermediates》2018,44(1):373-387
Research on Chemical Intermediates - The reactions of aldehydes and barbituric acid at low temperatures in magnetized water, as a green-promoting medium, provides 9-substituted-9H-diuracilopyrans... 相似文献
26.
Bushra S Bukhari M Imran Mahwish Bashir Saira Riaz Shahzad Naseem 《Journal of Sol-Gel Science and Technology》2018,87(3):554-567
Aim of the present work is to prepare zirconia nanofibers using microwave assisted sol–gel method. Both honey and microwave powers are employed as structure directing agents to improve the stability and reduce the crystallite size. Honey, acting as capping agent, prevents the particles from hard agglomeration. Soft agglomeration or less agglomeration results in smaller crystallite size that prevents the transformation of tetragonal to monoclinic phase resulting in stabilized tetragonal zirconia (t-ZrO2). Zirconium oxychloride is used as precursor of zirconium and deionized water as solvent. Effect of microwave powers, in the range of 100–900?W with interval of 200?W, on zirconia stabilization is observed. X-ray diffraction analysis shows the presence of phase pure t-ZrO2 at low microwave power ~?100?W with crystallite size ~?26?nm. Formation of phase pure t-ZrO2 at low microwave power is due to the presence of sufficient amount of honey to coat the zirconia crystals. Relatively higher x-ray density has been observed in case of phase pure t-ZrO2 at 100?W of microwave power. This high density and phase purity reveals the high value of hardness (~?1503?HV). Scanning electron microscopy analysis reveals the formation of well-separated nanofibers without agglomeration at 100?W. These nanofibers are purposed for bone implants and bone grafting. Structural transformation along with hard agglomeration is observed with increase in microwave powers from 500?W to 900?W. FTIR and Raman fundamental tetragonal bands, appearing at 490?cm?1 and 148?cm?1, respectively, confirm the formation of t-ZrO2 at low microwave power. Sample with phase purity exhibits high grain boundary resistance (1.95?MΩ) along with high dielectric constant (~?74) and low tangent loss (at log f?=?4.0). It is worth mentioning here that phase pure t-ZrO2 at very low microwave power (~100?W) with high density and well-separated nanofibers has been obtained without any post heat treatment. 相似文献
27.
Saira Shahzadi Saqib Ali Amin Badshah Farkhanda Shaheen Fiaz Ahmed Mohammed Fettouhi 《Journal of chemical crystallography》2006,36(9):567-570
The complex bis(4-methylpiperidine-dithiocarbamato-S,S′)-palladium(II) was synthesized by the reaction of 4-methyl-1-piperidine dithiocarbamic acid with palladium(II) chloride. Its structure was determined by X-ray crystal diffraction analysis. It crystallizes in the monoclinic P21/c space group with the crystal cell parameters a=8.6491(8) ?, b=18.7305(16) ?, c=11.9933(10) ?, β=107.074(1)°, V=1857.3(3) ?3 and Z=4. The palladium (II) ion is bonded to four sulfur atoms, belonging to two dithiocarbamate ligands, in a distorted square planar geometry. The X-ray data suggest a pronounced electronic delocalization in the two NCS2 moieties. 相似文献
28.
Saira Jabeen Shaukat Saeed Bakhtiar Muhammad Sagheer Gul Muhammad Farooq 《International Journal of Polymer Analysis and Characterization》2016,21(2):163-174
In this study, blends of chitosan (Cs) and bisphenol-F-diglycidyl ether (3.80 × 10?3 to 3.80 × 10?2 mol) were cast by the solution route. FT-IR results suggested that chitosan was cross-linked at terminal amino groups through diepoxide linkage. The chitosan films became less flexible and stiffer upon reaction with epoxy. Blending improved percentage elongation (31%) and toughness (10 MPa), whereas Young’s modulus (145 MPa) and tensile strength (45 MPa) were decreased. Extent of weight loss in Cs/BPFDGE was lower (15%) than that of original precursors (chitosan 33%). Moreover, blending of chitosan with BPFDGE increased water absorption properties due to generation of hydrophilic ?OH groups. 相似文献
29.
Ali P. Farajzadeh Muhammad Aslam Noor Saira Zainab 《Journal of Global Optimization》2009,45(2):229-235
In this paper, we introduce and consider a new class of complementarity problems, which is called the mixed quasi complementarity problems in a topological vector space. We show that the mixed quasi complementarity problems are equivalent to the mixed quasi variational inequalities. Using the KKM mapping theorem, we study the existence of a solution of the mixed quasi variational inequalities and mixed quasi complementarity problems. Several special cases are also discussed. Results obtained in this paper can be viewed as extension and generalization of the previously known results. 相似文献
30.
Saira Shahzadi Moazzam H. Bhatti Mohammmad Fettouhi 《Journal of organometallic chemistry》2006,691(8):1797-1802
Chloro-diorganotin(IV) complexes of 4-methyl-1-piperidine carbodithioic acid (4-MePCDTA) have been synthesized by the reaction with diorganotin dichloride in 1:1 molar ratio in anhydrous toluene. These newly synthesized complexes have been characterized by elemental, IR, multinuclear NMR (1H and 13C) and mass spectrometric studies. The crystal structures of complex 1 [Me2SnCl(4-MePCDT)] and 3 [Ph2SnCl(4-MePCDT)] have been determined by X-ray single crystal analysis, which show trigonal bipyramid geometry. These complexes were tested for their antimicrobial activity against six different plant and human pathogens. The screening results show that the complexes exhibit higher antibacterial and antifungal activity than the free ligand. 相似文献