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41.
Zafar A. Siddiqi Mohd Khalid Sarvendra Kumar M. Shahid Shabana Noor 《Spectrochimica acta. Part A, Molecular and biomolecular spectroscopy》2010,75(2):841-845
Spectral and molecular model computations on homo-dinuclear complexes [M2L2(H2O)2Cl2] [L = 1-(salicylaldeneamino)-3-hydroxypropane, M = Cr3+, Mn3+, Fe3+, Co3+, Ni3+ or Cu3+] are consistent with a distorted hexa-coordinate geometry. X-band EPR spectral data indicated a rhombic distortion around Cu(II) ion. Magnetic moment and 57Fe Mössbauer data confirmed a high-spin state electronic configuration (t2g3eg2, S = 5/2) and asymmetric ligand environment around Fe(III) with nuclear transitions Fe(±3/2 → 1/2) exhibiting Kramer's double degeneracy. The neighboring Fe(III) nuclei in the homo-dinuclear species are antiferromagnetically coupled. 相似文献
42.
Eugenol, the major constituent of clove oil, has been widely used for its anesthetic and analgesic action in dentistry. Eugenol exhibits pharmacological effects on almost all systems and our aim is to review the research work that has identified these pharmacological actions. Eugenol possesses significant antioxidant, anti-inflammatory and cardiovascular properties, in addition to analgesic and local anesthetic activity. The metabolism and pharmacokinetics of the compound in humans have been studied. Eugenol has also been used as a penetration enhancer. The compound is a very promising candidate for versatile applications, and the design of new drugs based on the pharmacological effects of eugenol could be beneficial. 相似文献
43.
Ijaz A. Bhatti Shahid Adeel M. Asghar Jamal Muhammad Safdar Muhammad Abbas 《Radiation Physics and Chemistry》2010,79(5):622-625
The effect of gamma radiation on the dyeing of cotton with extract of turmeric (Curcuma longa L.) powder has been investigated. Cotton fabric and turmeric powder were irradiated to absorbed doses of 1, 2, 3, 4 and 6 kGy using Co-60 gamma irradiator. Dyeing parameters such as temperature, pH and mordant concentration were optimized. Dyeing was performed using un-irradiated and irradiated cotton with the extracts of un-irradiated and irradiated turmeric powder in order to investigate the effect of radiation treatment on the colour strength of dyed fabric. The reported data of un-irradiated and irradiated fabrics dyed with un-irradiated and irradiated dyes were obtained using the spectraflash SF-650. The colourfastness to light, rubbing- and washing-fastness properties showed that gamma irradiation has improved the dyeing characteristics from fair to good. 相似文献
44.
In this paper, we propose a scheme for the teleportation of general two-partite entangled state of zero and one photon state from one bimodal cavity to another. The scheme can be realized by using cavity quantum electrodynamics (QED). 相似文献
45.
In this paper, we explored the conservation laws of cylindrically symmetric non-static space–times by using direct integration technique. This classification also covers non-static plane symmetric space–times, static cylindrically symmetric space–times and plane symmetric static space–times. In this paper, we will only present the results of non-static cylindrically symmetric and non-static plane symmetric space–times. The results of static cylindrically symmetric space–times and plane static space–times can be found in Shabbir and Khan (Mod Phys Lett A 25:525, 2010). It turns out that the non-static cylindrically symmetric space–times admit four, five, or seven conservation laws. It is important to note that the above space–times admit at least one or at the most four extra conservation laws. 相似文献
46.
Binary 3-point scheme, developed by Hormann and Sabin [Hormann, K. and Sabin, Malcolm A., 2008, A family of subdivision schemes with cubic precision, Computer Aided Geometric Design, 25, 41-52], has been modified by introducing a tension parameter which generates a family of C1 limiting curves for certain range of tension parameter. Ternary 3-point scheme, introduced by Siddiqi and Rehan [Siddiqi, Shahid S. and Rehan, K., 2009, A ternary three point scheme for curve designing, International Journal of Computer Mathematics, In Press, DOI: 10.1080/00207160802428220], has also been modified by introducing a tension parameter which generates family of C1 and C2 limiting curves for certain range of tension parameter. Laurent polynomial method is used to investigate the continuity of the subdivision schemes. The performance of modified schemes has been demonstrated by considering different examples along with its comparison with the established subdivision schemes. 相似文献
47.
Bashir M. S. Ali S. Shahzadi S. Shahid M. 《Russian Journal of General Chemistry》2015,85(6):1532-1537
Russian Journal of General Chemistry - The new organotin(IV) complexes have been synthesized by the reaction of l-lysine monohydrate with CS2 and R2SnCl2/R3SnCl. The organotin(IV) complexes and the... 相似文献
48.
Diorganotin(IV) Complexes with Monohydrate Disodium Salt of Iminodiacetic Acid: Synthesis,Characterization, Crystal Structure and Biological Activities 下载免费PDF全文
Shabbir Hussain Saqib Ali Saira Shahzadi Corrado Rizzoli Muhammad Shahid 《中国化学会会志》2015,62(9):793-802
Diorganotin(IV) derivatives have been synthesized by the reaction of R2SnL2 (R=n‐Bu 1 , Ph 2 ) with monohydrate disodium salt of iminodiacetic acid ( Na2L ) in 1 : 1 M/L ratio under reflux conditions. The compounds have been characterized by FT‐IR, NMR (1H and 13C) spectoscopy, electron ionization mass spectrometry (EIMS), thermogravimetric analyses (TGA) and single crystal XRD. FTIR data indicates a mono‐dentate binding mode of the carboxylic acid group as well as participation of the amino nitrogen and aqua oxygen in coordination with organotin(IV) moieties. NMR data demonstrates a tetra‐coordinated environment around tin(IV) in solution. Mass spectrometric and thermogravimetric analyses verify the close similarities between the molecular structures of both complexes. The thermal stability of diphenyltin(IV) derivative ( 2 ) was found slightly higher than that of the free ligand ( Na2L ). Single crystal X‐ray analysis of the complex 1 have shown a hexa‐coordinated geometry around Sn(IV) with trans configuration. There are evidences for the existence of intermolecular hydrogen bonding in the structure of the complexes. The products displayed significant antibacterial and antifungal activities in contrast to the biologically inactive ligand precursor. However, the hemolytic cytoxicity of the complexes was comparatively high than the free ligand. 相似文献
49.
Castillo-Martínez E Bieringer M Shafi SP Cranswick LM Alario-Franco MÁ 《Journal of the American Chemical Society》2011,133(22):8552-8563
A novel ScVO(3) perovskite phase has been synthesized at 8 GPa and 1073 K from the cation-disordered bixbyite-type ScVO(3). The new perovskite has orthorhombic symmetry at room temperature, space group Pnma, and lattice parameters a = 5.4006(2) ?, b = 7.5011(2) ?, and c = 5.0706(1) ? with Sc(3+) and V(3+) ions fully ordered on the A and B sites of the perovskite cell. The vanadium oxygen octahedra [V-O(6)] display cooperative Jahn-Teller (JT) type distortions, with predominance of the tetragonal Q(3) over the orthorhombic Q(2) JT modes. The orthorhombic perovskite shows Arrhenius-type electrical conductivity and undergoes a transition to triclinic symmetry space group P-1 close to 90 K. Below 60 K, the magnetic moments of the 4 nonequivalent vanadium ions undergo magnetic long-range ordering, resulting in a magnetic superstructure of the perovskite cell with propagation vector (0.5, 0, 0.5). The magnetic moments are confined to the xz plane and establish a close to zigzag antiferromagnetic mode. 相似文献
50.
Simultaneous determination of perfluoroalkyl phosphonates, carboxylates, and sulfonates in drinking water 总被引:2,自引:0,他引:2
A trace analytical method based on high performance liquid chromatography coupled to quadrupole time-of-flight high resolution mass spectrometry was developed for simultaneous determination of perfluoroalkyl phosphonates (PFPAs, carbon chain lengths C6,8,10), perfluoroalkyl carboxylates (PFCAs, C5-12), and perfluoroalkyl sulfonates (PFSAs, C4,6,8,10) in drinking water (tap water). Analytes were enriched on a mixed mode co-polymeric sorbent (C8+quaternary amine) using solid phase extraction. Chromatographic separation was achieved on a Zorbax Extend C18 reversed phase column using a mobile phase gradient consisting of water, methanol, and acetonitrile containing 2mM ammonium acetate and 5 mM 1-methyl piperidine. The mass spectrometer was operated in electrospray negative ion mode. Use of 1-methyl piperidine in the mobile phase resulted in a significant increase in instrument sensitivity for PFPAs through improved chromatographic resolution, background suppression, and increased ionization efficiency. Method detection limits for extraction of 500 mL tap water were in the ranges of 0.095-0.17 ng/L, 0.027-0.17 ng/L, and 0.014-0.052 ng/L for PFPAs, PFCAs, and PFSAs, respectively. Whole method recoveries at a spiking level of 0.5 ng/L to 500 mL HPLC grade water were 40-56%, 56-97%, and 55-77% for PFPAs, PFCAs, and PFSAs, respectively. A matrix effect (signal enhancement) was observed in the detection of PFPAs in tap water extracts, leading to calculated recoveries of 249-297% at a 0.5 ng/L spiking level. This effect resulted in an additional improvement of method sensitivity for PFPAs. To compensate for the matrix effect, PFPAs in tap water were quantified using matrix-matched and extracted calibration standards. The method was successfully applied to the analysis of drinking water collected from six European countries. PFPAs were not detected except for perfluorooctyl phosphonate (PFOPA) at close to the detection limit of 0.095 ng/L in two water samples from Amsterdam, the Netherlands. Highest levels were found for perfluorobutane sulfonate (PFBS, 18.8 ng/L) and perfluorooctanoate (PFOA, 8.6 ng/L) in samples from Amsterdam as well as for perfluorooctane sulfonate (PFOS, 8.8 ng/L) in tap water from Stockholm, Sweden. 相似文献