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61.
62.
John Burgess John Fawcett David R. Russell Syeda R. Gilani 《Acta Crystallographica. Section C, Structural Chemistry》2000,56(6):649-650
The title compound, [Co(C5H7O2)2], contains isolated molecules. The Co atom is located on a centre of symmetry with the bidentate ligands adopting a square‐planar geometry about the Co atom. 相似文献
63.
Sreeyuth Lal Lily D. Poulikakos Marjan Sedighi Gilani Iwan Jerjen Peter Vontobel Manfred N. Partl Jan C. Carmeliet Dominique Derome 《Transport in Porous Media》2014,105(2):431-450
Porous asphalt (PA), a highly porous hydrophobic composite material, is subjected to water uptake and the process is documented with neutron radiography (NR). While the un-aged laboratory-prepared PA specimens do not show any water uptake, we observe uptake in aged PA even though the bitumen binder is a hydrophobic material. The moisture content distribution plots derived from the NR images clearly identify regions in the aged specimens where water uptake is active. Two-dimensional degree of saturation (DoS) distribution images, which are obtained by combining micro-computer tomography and NR images, identify those pores where saturated flow is certainly active. However, to clearly distinguish between saturated and unsaturated flows in the remaining wet pores, the DoS distribution images are read together with the three-dimensional PA microstructure obtained by micro-CT. It is observed that uptake begins mainly as unsaturated film/corner flow at large well-defined pores. As this uptaken water travels further into the material, the flow transforms into a combination of saturated flow and unsaturated film/corner flow. Saturated flow is seen to be mostly active in the small pores within the mastic. From the observed succession of unsaturated and saturated flows in an aged PA specimen, it can be concluded that years of environmental and mechanical loading has resulted in the stripping of binder from the aggregate surfaces and has consequently exposed patches of hydrophilic aggregate to water, which enables the capillary uptake of water. We also simulate an absolute permeability experiment and observe that relatively less tortuous and more connected paths play an important role in determining the preferential path of the uptaken water. 相似文献
64.
This study describes the antidiarrhoeal and bronchodilatory activities of Valeriana wallichii D.C. (Valerianaceae). The crude extract of V. wallichii (Vw.Cr) caused inhibition of castor oil-induced diarrhoea in mice at 300-600?mg?kg?1. In guinea-pig trachea, Vw.Cr concentration dependently (0.03-3.0?mg?mL?1) relaxed the low K+ (25?mM)-induced contractions, with a mild effect on the contractions induced by high K+ (80?mM). In the presence of glibenclamide, the relaxation of low K+-induced contractions was prevented. Similarly, cromakalim caused glibenclamide-sensitive inhibition of low K+, without any effect on high K+. These results indicate that V. wallichii exhibits antidiarrhoeal and bronchodilatory activities, possibly through K+ channel activation, and thus reveal its medicinal usefulness in hyperactive gut and airway disorders such as diarrhoea and asthma. 相似文献
65.
Shamsa Bibi Aamna Imtiaz Shabbir Muhammad Shafiq urRehman Aijaz Rasool Chaudhry Abdullah G. Al-Sehemi Bakhet Ahmad Alqurashy Mazhar Amjad Gilani 《International journal of quantum chemistry》2024,124(7):e27362
The current study reports tailoring the electronic donor structures of organic dyes to modify their optical and nonlinear optical (NLO) response properties. Five (5) tri-phenyl amine (TPA) based Donor-π-Acceptor (D-π-A) organic dyes with the codes ICAA1 , ICAA2 , ICAA3 , ICAA4 , and ICAA5 were designed and investigated for their optical and NLO properties using quantum chemical methods. Optical and NLO properties of these dyes were studied by CAM-B3LYP method and 6-311G* basis set. The focus has been on the impact of adding secondary donors and shifting their substitutions at ortho (o), meta (m) and para (p) positions. Among all designed compounds, ICAA4 showed the highest amplitude of average third-order NLO polarizability <γ>, which is calculated to be 1316 × 10−36 esu. Time-dependent Density Functional Theory (TD-DFT) method was used to determine how a change in the position of the donor affected the excitation energy (Eg) and NLO response properties. The findings showed that changing the position of the secondary donor results in a red shift among absorption spectra as well as the increase in their NLO responses. Complete process of intramolecular charge transfer (ICT) has been investigated in terms of different optical parameters such as frontier molecular orbitals (FMOs), molecular electrostatic potentials (MEPs), transition density matrix (TDMs), density of states (DOS), electron density difference (EDD), and natural bond orbital (NBO) analysis. Our calculations for study of ICT process indicate that p-position of methoxy group performs better among all other positions and even it has better NLO response properties than the compound with three collective methoxy groups. The calculated Voc values of all designed molecules range from 1.09 to 1.30, all of them are positive while their ΔGinject is found to be in the range of −0.87 to −1.79 eV indicating their decent potential for photovoltaic applications. The studied optical, NLO and photovoltaic parameters illustrated that ICAA1 to ICAA5 are appropriate molecules not only for NLO applications but also for efficient photovoltaic purposes. 相似文献
66.
Accurate standardized methods for the determination of amino acid in foods are required to assess the nutritional safety and compositional adequacy of sole source foods such as infant formulas and enteral nutritionals, and protein and amino acid supplements and their hydrolysates, and to assess protein claims of foods. Protein digestibility-corrected amino acid score (PDCAAS), which requires information on amino acid composition, is the official method for assessing protein claims of foods and supplements sold in the United States. PDCAAS has also been adopted internationally as the most suitable method for routine evaluation of protein quality of foods by the Food and Agriculture Organization/World Health Organization. Standardized methods for analysis of amino acids by ion-exchange chromatography have been developed. However, there is a need to develop validated methods of amino acid analysis in foods using liquid chromatographic techniques, which have replaced ion-exchange methods for quantifying amino acids in most laboratories. Bioactive peptides from animal and plant proteins have been found to potentially impact human health. A wide range of physiological effects, including blood pressure-lowering effects, cholesterol-lowering ability, antithrombotic effects, enhancement of mineral absorption, and immunomodulatory effects have been described for bioactive peptides. There is considerable commercial interest in developing functional foods containing bioactive peptides. There is also a need to develop accurate standardized methods for the characterization (amino acid sequencing) and quantification of bioactive peptides and to carry out dose-response studies in animal models and clinical trials to assess safety, potential allergenicity, potential intolerance, and efficacy of bioactive peptides. Information from these studies is needed for determining the upper safe levels of bioactive peptides and as the basis for developing potential health claims for bioactive peptides. This information is, in turn, needed by regulatory agencies for developing appropriate policy and regulations on adding these substances to foods and for determining if health claims are scientifically substantiated. 相似文献
67.
S.M. Sohail Gilani Saad Tariq M. Imran Jamil Bashir Tahir M.A. Faridi 《Chinese Journal of Physics (Taipei)》2018,56(1):308-314
Generalized gradient approximation and Modified Becke and Johnson (mBJ) potential scheme, within density functional theory, has been implemented to evaluate the structural, electronic and thermo-elastic attributes of SrTcO3. The structural stability of the very compound has been probed from tolerance factor, elastic stability criterion and ground state optimizations. In the study of electronic properties, formation of band-gap has been resolved by using density of states and from electron spin density contour plots. It is for the first time that mechanical and thermo-dynamical properties have been studied in terms of elastic constants, melting temperature, enthalpy of formation and Debye temperature. Our results have shown that SrTcO3 exhibit a stable ductile nature that makes it a convincing candidate for high temperature electronic applications. 相似文献
68.
Jasmeet Kaur Md. Khalid Anwer Ali Sartaj Bibhu Prasad Panda Abuzer Ali Ameeduzzafar Zafar Vinay Kumar Sadaf Jamal Gilani Chandra Kala Mohamad Taleuzzaman 《Molecules (Basel, Switzerland)》2022,27(4)
The objective of the current research is to develop ZnO-Manjistha extract (ZnO-MJE) nanoparticles (NPs) and to investigate their transdermal delivery as well as antimicrobial and antioxidant activity. The optimized formulation was further evaluated based on different parameters. The ZnO-MJE-NPs were prepared by mixing 10 mM ZnSO4·7H2O and 0.8% w/v NaOH in distilled water. To the above, a solution of 10 mL MJE (10 mg) in 50 mL of zinc sulfate was added. Box–Behnken design (Design-Expert software 12.0.1.0) was used for the optimization of ZnO-MJE-NP formulations. The ZnO-MJE-NPs were evaluated for their physicochemical characterization, in vitro release activity, ex vivo permeation across rat skin, antimicrobial activity using sterilized agar media, and antioxidant activity by the DPPH free radical method. The optimized ZnO-MJE-NP formulation (F13) showed a particle size of 257.1 ± 0.76 nm, PDI value of 0.289 ± 0.003, and entrapment efficiency of 79 ± 0.33%. Drug release kinetic models showed that the formulation followed the Korsmeyer–Peppas model with a drug release of 34.50 ± 2.56 at pH 7.4 in 24 h. In ex vivo studies ZnO-MJE-NPs-opt permeation was 63.26%. The antibacterial activity was found to be enhanced in ZnO-MJE-NPs-opt and antioxidant activity was found to be highest (93.14 ± 4.05%) at 100 µg/mL concentrations. The ZnO-MJE-NPs-opt formulation showed prolonged release of the MJE and intensified permeation. Moreover, the formulation was found to show significantly (p < 0.05) better antimicrobial and antioxidant activity as compared to conventional suspension formulations. 相似文献
69.
70.
Journal of Solution Chemistry - This study reports the experimental permittivity data for the polar binary systems of 1,3-propanediol with two primary octanol isomers (1-octanol and... 相似文献