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11.
N. U. Khattak A. A. Qureshi M. Akram M. Ayub Khan I. E. Qureshi K. Mehmood H. A. Khan 《Radiation measurements》2001,34(1-6):409-413
A group of alkaline igneous rocks is exposed in the north of the Peshawar Plain, extending from Tarbela in the east up to Loe–Shilman near the Pakistan–Afghanistan border in the west. The alkaline rocks consist mainly of granites, syenites, gabbros, ijolites and carbonatites. Granitic gneisses of Paleozoic age are exposed at the Malakand and further westward at Sillai Patti. However, the fission-track dating studies on zircon, based on the present work, indicate that the age of the Sillai Patti granite gneiss is less than the absolute age of granite gneisses. Therefore, the zircon fission-track age of 24.28±2.97 Ma of the Sillai Patti granite gneiss, represents a time of post-metamorphic denudation history of the area, when these rocks passed through the 210°C isotherm, corresponding to a depth of about 6.7 km inside the earth's crust from their present position if a paleogeothermal gradient of 30°C/km is assumed to have prevailed. Our average fission-track zircon age of 24.28±2.97 Ma is very similar to the average fission-track zircon age of 25.4±0.7 Ma of Mansehra granites. Average cooling rates of the Mansehra and Sillai Patti granite gneisses have been computed to be (8.00±0.22)°C/Ma and (8.00±0.98)°C/Ma, while the average denudation rates of the Mansehra and Sillai Patti granite gneisses have been computed to be (0.262±0.007) and (0.274±0.034) mm/yr, respectively, on the basis of zircon fission-track ages for the period between 25 Ma and the present time. This indicates that the two complexes have experienced similar average cooling/uplift-induced denudation histories during the last 25 Ma or so. 相似文献
12.
M. Q. Mehmood Hong Liu Kun Huang Shengtao Mei Aaron Danner Boris Luk'yanchuk Shuang Zhang Jinghua Teng Stefan A. Maier Cheng‐Wei Qiu 《Laser \u0026amp; Photonics Reviews》2015,9(6):674-681
This work presents analytical, numerical and experimental demonstrations of light diffracted through a logarithmic spiral (LS) nanoslit, which forms a type of switchable and focus‐tunable structure. Owing to a strong dependence on the incident photon spin, the proposed LS‐nanoslit converges incoming light of opposite handedness (to that of the LS‐nanoslit) into a confined subwavelength spot, while it shapes light with similar chirality into a donut‐like intensity profile. Benefitting from the varying width of the LS‐nanoslit, different incident wavelengths interfere constructively at different positions, i.e., the focal length shifts from 7.5 μm (at λ = 632.8 nm) to 10 μm (at λ = 488 nm), which opens up new opportunities for tuning and spatially separating broadband light at the micrometer scale.
13.
Boundary layer stagnation point flow of Casson fluid over a Riga plate of variable thickness is investigated in present article. Riga plate is an electromagnetic actuator consists of enduring magnets and gyrated aligned array of alternating electrodes mounted on a plane surface. Physical problem is modeled and simplified under appropriate transformations. Effects of thermal radiation and viscous dissipation are incorporated. These differential equations are solved by Keller Box Scheme using MATLAB. Comparison is given with shooting techniques along with RangeKutta Fehlberg method of order 5. Graphical and tabulated analysis is drawn. The results reveal that Eckert number,radiation and fluid parameters enhance temperature whereas they contribute in lowering rate of heat transfer. The numerical outcomes of present analysis depicts that Keller Box Method is capable and consistent to solve proposed nonlinear problem with high accuracy. 相似文献
14.
Areej Mohammad Al-Taweel Ghada Ahmed Fawzy Afsar Khan Rashad Mehmood Abdul Malik 《Natural product research》2015,29(21):1978-1984
A new phenolic glucoside, abeliaside, along with four known compounds, 5,6,7,4′-tetrahydroxy flavones, caffeic acid, 4-O-caffeoylquinic acid and caffeic acid glucoside, was isolated from the leaves of Abelia triflora R. Br. (Caprifoliaceae). The structure of the new compound was elucidated by different spectroscopic techniques. Compounds 1–5 were assayed for their anticancer activities against two cancerous human cell lines, MCF-7 and PC-3 cells, and normal Vero cell line using the crystal violet staining method. From the results it could be seen that caffeic acid possessed the highest anticancer effect against MCF-7 (IC50: 17 μg/mL) and PC-3 (IC50: 20.1 μg/mL) compared to vinblastine sulphate as reference drug (IC50: 4.6, 2.8 μg/mL). The other compounds showed weak anticancer activity on both cell lines. 相似文献
15.
Akhtar J Mehmood RF Malik MA Iqbal N O'Brien P Raftery J 《Chemical communications (Cambridge, England)》2011,47(6):1899-1901
We describe for the first time the use of a single source precursor to deposit thin films and nanocrystals of palladium selenide. 相似文献
16.
Abbas S. Imtiaz-ud-Din Mehmood M. Raheel A. Ayub R. Zahid M. Tahir M. N. 《Russian Journal of Coordination Chemistry》2021,47(12):891-902
Russian Journal of Coordination Chemistry - A series of ferrocenyl substituted hydrazones (I–VII) derived from ferrocene carboxaldehyde and substituted hydrazides have been prepared and... 相似文献
17.
Abd Elmoneim O. Elkhalifa Eyad Al-Shammari Mohd Adnan Jerold C. Alcantara Khalid Mehmood Nagat Elzein Eltoum Amir Mahgoub Awadelkareem Mushtaq Ahmad Khan Syed Amir Ashraf 《Molecules (Basel, Switzerland)》2021,26(12)
Abelmoschus esculentus (Okra) is an important vegetable crop, widely cultivated around the world due to its high nutritional significance along with several health benefits. Different parts of okra including its mucilage have been currently studied for its role in various therapeutic applications. Therefore, we aimed to develop and characterize the okra mucilage biopolymer (OMB) for its physicochemical properties as well as to evaluate its in vitro antidiabetic activity. The characterization of OMB using Fourier-transform infrared spectroscopy (FT-IR) revealed that okra mucilage containing polysaccharides lies in the bandwidth of 3279 and 1030 cm−1, which constitutes the fingerprint region of the spectrum. In addition, physicochemical parameters such as percentage yield, percentage solubility, and swelling index were found to be 2.66%, 96.9%, and 5, respectively. A mineral analysis of newly developed biopolymers showed a substantial amount of calcium (412 mg/100 g), potassium (418 mg/100 g), phosphorus (60 mg/100 g), iron (47 mg/100 g), zinc (16 mg/100 g), and sodium (9 mg/100 g). The significant antidiabetic potential of OMB was demonstrated using α-amylase and α-glucosidase enzyme inhibitory assay. Further investigations are required to explore the newly developed biopolymer for its toxicity, efficacy, and its possible utilization in food, nutraceutical, as well as pharmaceutical industries. 相似文献
18.
Uzma Yasmeen Fazal Haq Mehwish Kiran Arshad Farid Naveed Ullah Tariq Aziz Muhammad Haroon Sahid Mehmood Muhammad Muzammal Shakira Ghazanfar Majid Alhomrani Abdulhakeem S. Alamri Syed Mohammed Basheeruddin Asdaq Saleh A. Alghamdi Irfan Ullah 《Molecules (Basel, Switzerland)》2022,27(18)
In this research, a new biodegradable and eco-friendly adsorbent, starch-grafted polymethyl methacrylate (St-g-PMMA) was synthesized. The St-g-PMMA was synthesized by a free radical polymerization reaction in which methyl methacrylate (MMA) was grafted onto a starch polymer chain. The reaction was performed in water in the presence of a potassium persulfate (KPS) initiator. The structure and different properties of the St-g-PMMA was explored by FT-IR, 1H NMR, TGA, SEM and XRD. After characterization, the St-g-PMMA was used for the removal of MB dye. Different adsorption parameters, such as effect of adsorbent dose, effect of pH, effect of initial concentration of dye solution, effect of contact time and comparative adsorption study were investigated. The St-g-PMMA showed a maximum removal percentage (R%) of 97% towards MB. The other parameters, such as the isothermal and kinetic models, were fitted to the experimental data. The results showed that the Langmuir adsorption and pseudo second order kinetic models were best fitted to experimental data with a regression coefficient of R2 = 0.93 and 0.99, respectively. 相似文献
19.
Hussain Shafqat Öztop Hakan F. Mehmood Khalid Ali Mohamed E. 《Journal of Thermal Analysis and Calorimetry》2019,137(1):289-306
Journal of Thermal Analysis and Calorimetry - In the present study, a computational work has been done to see the heat transfer, fluid flow and temperature distribution in a lid-driven cavity due... 相似文献
20.
Zaheer Ahmad Itrat Fatima Sajid Mehmood Rehana Ifzal Abdul Malik Nighat Afza 《Helvetica chimica acta》2008,91(1):73-78
Three new 20,24‐epoxydammarane triterpenes, santolins A–C ( 1 – 3 ), were isolated from the AcOEt‐soluble fraction of the MeOH extract of Salvia santolinifolia (whole plant). Their structures were assigned based on 1H‐NMR, 13C‐NMR (DEPT), and 2D‐NMR analyses, in combination with HR‐MS experiments and comparison with literature data of related compounds. 相似文献