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1.
Saify ZS Mushtaq N Khan KM Perveen S Shah ST Abdel-Jalil RJ Fecker M Voelter W 《Chemical & pharmaceutical bulletin》2005,53(1):64-66
A new series of 4-(4'-chlorophenyl)-4-hydroxypiperidine derivatives (2-5), substituted at nitrogen, were synthesized and tested as potential analgesic compounds as well as evaluated for their effect on hypotensive activity. Results showed that all the derivatives exhibit significant analgesic activity in male Wistar rats at a dose of 50 mg/kg of body weight after intramuscular injection, when tested by thermal stimuli (tail flick test). Pethidine was used as reference drug. Compounds 2, 3 and 5 produced reduction in blood pressure in normotensive rat. 相似文献
2.
以两亲性嵌段共聚物聚乙二醇-b-聚四乙烯基吡啶(PEO-b-P4VP)为模板制备聚联苯胺微/纳米颗粒,调节模板剂胶束溶液pH,得到了一系列形貌和尺寸可控的聚联苯胺微/纳米颗粒。利用红外光谱、核磁共振、透射电镜、循环伏安、恒电流放电、交流阻抗等测试对材料的结构和性能进行了表征。模板法合成的聚联苯胺为平均直径小于200nm的亚微米至纳米级棒状颗粒,其直径随着模板剂胶束溶液pH的降低而增加。所得聚联苯胺颗粒均显示了一定的电化学活性,当电流密度为1A/g时,聚联苯胺的比电容量达到306.3F/g,经过长时间的充放电测试,不同条件下合成的聚联苯胺的容量衰减率均很小,表现出良好的循环稳定性且各样品电化学性能呈现出随着直径的减小而增强的趋势。 相似文献
3.
Saima Maher Shagufta Rasool Shagufta Perveen Rasool Bakhsh Tareen 《Natural product research》2018,32(1):1-6
Trichosides A (1) and B (2), new withanolide glucosides, have been isolated from the n-butanolic fraction of the 75% methanolic extract of aerial parts of Tricholepis eburnea. Their structures were elucidated through spectroscopic analysis including ESI-MS, 2D NMR and acid hydrolysis. 相似文献
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Perveen R Jamil Y Ashraf M Ali Q Iqbal M Ahmad MR 《Photochemistry and photobiology》2011,87(6):1453-1463
The water-soaked seeds of sunflower were exposed to low power continuous wave He-Ne laser irradiation of energies 0, 100, 300 and 500 mJ to evaluate the effect on various biochemical, physiological, growth and yield parameters of sunflower. The experiments which consisted of four replicates arranged in a completely randomized design (CRD) were carried out under the greenhouse conditions. The physiological attributes like, photosynthetic rate (A), transpiration rate (E), intrinsic CO(2) concentration (C(i) ), stomatal conductance (g(s)), chlorophyll a and b contents, relative membrane permeability and leaf water (ψ(w)), osmotic (ψ(s)) and turgor (ψ(p)) potentials, relative water contents and leaf area increased significantly as compared to control due to He-Ne treatment of seeds. The activities of superoxide dismutase, peroxidase and catalases and contents of total soluble proteins, malondialdehyde, proline and leaf total phenolic also increased due to laser treatment. Significant increase in growth parameters of sunflower like shoot fresh and dry masses, root fresh and dry masses, root and shoot lengths, number of leaves per plant and stem diameter has also been observed. The contents of K, Ca and Mg in shoot and root were also increased and an overall increase of up to 28.12% was observed due to laser treatment. 相似文献
6.
Jabbar A Tufail M Arshed W Bhatti AS Ahmad SS Akhter P Dilband M 《Isotopes in environmental and health studies》2010,46(4):495-505
In Rechna Doab, samples of the most common vegetation, perennial grass Desmostachya bipinnata (dab), were collected along with soil samples from 29 sites. Natural radioactivity of 22?Ra, 232Th/22?Ac and ??K was measured by using high purity germanium-based gamma ray spectrometer. Activity concentration levels of 22?Ra, 232Th/22?Ac and ??K in soil were found to be 46.8 ± 6.2 (36.0-57.6), 61.4 ± 5.9 (48.2-73.2) and 644.8 ± 73.9 (537.7-868.4) Bq kg?1 (dry mass), respectively, and those in vegetation were 2.74 ± 1.70 (1.00-6.39), 2.24 ± 0.59 (1.56-2.61) and 172.72±113.37 (53.14-469.24) Bq kg?1 (dry mass), respectively. The measured values of the activity concentration in vegetation are comparable with some other international data. Calculated soil to vegetation transfer factors of 22?Ra, 22?Ac and ??K were 0.06 ± 0.03 (0.02-0.14), 0.04 ± 0.01 (0.03-0.04) and 0.26 ± 0.16 (0.09-0.69). The mean outdoor absorbed dose rate in air for the area under study was determined as 8.22 nGy h?1 and the mean indoor absorbed dose rate in air was 11.52 nGy h?1. The total annual effective dose to the general public from the vegetation was found to be (0.02-0.16) mSv, which is below the recommended limit value of 1 mSv y?1 for the general public. The dab vegetation under study was found to be radiologically safe for the population and environment. 相似文献
7.
Abdul Jabbar Muhammad Tufail Waheed Arshed Arshed Salem Bhatti Syed Salman Ahmad Perveen Akhter 《Isotopes in environmental and health studies》2013,49(4):495-505
In Rechna Doab, samples of the most common vegetation, perennial grass Desmostachya bipinnata (dab), were collected along with soil samples from 29 sites. Natural radioactivity of 226Ra, 232Th/228Ac and 40K was measured by using high purity germanium-based gamma ray spectrometer. Activity concentration levels of 226Ra, 232Th/228Ac and 40K in soil were found to be 46.8±6.2 (36.0–57.6), 61.4±5.9 (48.2–73.2) and 644.8±73.9 (537.7–868.4) Bq kg?1 (dry mass), respectively, and those in vegetation were 2.74±1.70 (1.00–6.39), 2.24±0.59 (1.56–2.61) and 172.72±113.37 (53.14–469.24) Bq kg?1 (dry mass), respectively. The measured values of the activity concentration in vegetation are comparable with some other international data. Calculated soil to vegetation transfer factors of 226Ra, 228Ac and 40K were 0.06±0.03 (0.02–0.14), 0.04±0.01 (0.03–0.04) and 0.26±0.16 (0.09–0.69). The mean outdoor absorbed dose rate in air for the area under study was determined as 8.22 nGy h?1 and the mean indoor absorbed dose rate in air was 11.52 nGy h?1. The total annual effective dose to the general public from the vegetation was found to be (0.02–0.16) mSv, which is below the recommended limit value of 1 mSv y?1 for the general public. The dab vegetation under study was found to be radiologically safe for the population and environment. 相似文献
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Shamsul Qamar Seemab Bashir Sadia Perveen Andreas Seidel-Morgenstern 《液相色谱法及相关技术杂志》2019,42(1-2):16-30
This article presents analytical solutions of the general rate model (GRM), the lumped kinetic model (LKM), and the simpler equilibrium dispersive model (EDM) for core-shell particles and linear adsorption isotherms. The solutions in the Laplace domain are applied to derive analytical expressions for the temporal moments of these models. The results provide relations between the model specific kinetic parameters by matching one or more of the temporal moments. Several case studies are considered for illustration. The results show that simpler models are in many cases as good as the most detailed GRM if their kinetic parameters fulfill the matching relations. Thus, it is possible to reliably predict elution profiles using the simpler models. The derived analytical expressions can also be utilized to efficiently estimate model parameters from experimentally observed elution profiles to further optimize core-shell particles and to identify suitable column sizes and operating conditions. 相似文献
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S. Masood W. Rehman Z. Khan H. Arshad S. Begum A. Perveen 《Journal of Structural Chemistry》2018,59(5):1148-1157
Densities of acefylline piperazine (AP) in aqueous, aqueous methanol, and aqueous ethylene glycol (10% v/v) systems are determined in the concentration range 0.04-0.14±0.001 mol/dm3 at different temperatures (298.15-318.15 K) with the interval of 5 K. The apparent molar volume (φv), the partial molar volume \((\phi_v^0)\), and the ion-ion interaction parameter (Sv) are calculated using the Masson equation. Partial molar expansibilities \((\phi_E^0)\), which indicate the presence or absence of the caging or packing effect, are also evaluated and discussed. The results are interpreted in terms of solute-solvent and solute-solute interactions of AP in aqueous, aqueous methanol, and aqueous ethylene glycol systems. The structure-breaking and structure-making properties of AP are inferred by the sign of Hepler′s criterion \((\partial^2\phi_v^0/\partial{T}^2)_p\), i.e. the second derivative of the partial molar volume with respect to the temperature at the constant pressure. 相似文献
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A microwave-assisted, environmentally friendly, high-yielding, time-saving synthesis of medicinally important 3-substituted isocoumarins was carried out in a single step by direct condensation of homophthalic acid with aryol and acyl chlorides under solvent-free conditions without any solid support. The synthesised isocoumarins were structurally characterised by microanalysis, 1H NMR, EI, IR and UV. 相似文献