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11.
Shaukat Mahmood Nek M. Shaikh M.A. Kalyar M. Rafiq N.K. Piracha M.A. Baig 《Journal of Quantitative Spectroscopy & Radiative Transfer》2009,110(17):1840-1850
In the present work emission and absorption spectroscopy have been used to determine the plasma parameters of neon in a hollow cathode discharge lamp. The excitation temperature is determined using the intensity ratio method and Boltzmann's plot method whereas the electron density is determined from the Stark broadening of the spectral lines. The behavior of the optogalvanic signal as a function of laser energy has been studied for three transitions from the 2p53s [1/2]2 metastable state following ΔJ=ΔK=0, ±1 dipole selection rules. The saturation technique has been used to measure the photoionization cross section from three intermediate states 2p53p′ [1/2]1, 2p53p′ [3/2]2 and 2p53p [5/2]3 up to the 2p5 2P1/2 ionization threshold. 相似文献
12.
Mehwish Nawaz Haji Muhammad Shoaib Khan Naveed Akhtar Talha Jamshed Rubina Qaiser Hina Shoukat Mehrin Farooq 《Photochemistry and photobiology》2019,95(5):1243-1248
Solar radiations trigger the physiological alteration in skin which progress toward photoaging. Sunscreens are known to be effective against the photodamaging effects of sunlight. The purpose of this study was to evaluate the extent to which aging signs caused by real‐life sunlight exposure could be avoided by comparing various parameters between sun‐exposed and sun‐protected skin using noninvasive probes. Female volunteers (n = 11) after getting their consent were provided with marketed sunscreen product to apply onto their skin for 6 months. Measurements were scheduled every 15 days from the baseline reading for 6 months. Cutometer, Mexameter and Corneometer were used for evaluation of facial skin parameters. Clinical evaluations showed the effects of sunlight exposure on different skin parameters by comparing sun‐protected and unprotected skin, where Gross elasticity (R2), Net elasticity (R5), Viscoelasticity (R6) and Biological elasticity (R7) showed insignificant results, while Hydration, Melanin and Erythema showed significant results. Sun‐exposed skin presented 0.72%, 0.66%, 0.77%, 1.39%, 1.99%, 2.01% and 3.15% changes in R2, R5, R6 and R7, melanin, erythema and hydration, respectively, which were potentially prevented by sunscreen application. Premature aging is inhibited by following photoprotective regimen on routine basis, emphasizing the potential benefit of sunscreen against early aging signs. 相似文献
13.
14.
Ljubomir iri Arif Rafiq Nenad Caki 《Nonlinear Analysis: Theory, Methods & Applications》2009,70(12):4332-4337
In this note, we speed up the convergence of the Picard sequence of iterations for strongly accretive and strongly pseudo-contractive mappings. Our results improve the results of Chidume [C.E. Chidume, Picard iteration for strongly accretive and strongly pseudo-contractive Lipschitz maps, ICTP Preprint no. IC2000098; C.E. Chidume, Iterative Algorithms for Non-expansive Mappings and Some of Their Generalizations, in: Nonlinear Analysis and Applications: To V. Lakshmikantham on his 80th Birthday, vol. 1, 2, Kluwer Acad. Publ, Dordrecht, 2003, pp. 383–429], and Liu [L. Liu, Approximation of fixed points of a strictly pseudo-contractive mapping, Proc. Amer. Math. Soc. 125 (2) (1997) 1363–1366], and some other known results. The technique of the proof, presented in this paper, is different from the technique used by Chidume. 相似文献
15.
Arif Rafiq Nazir Ahmad Mir Farooq Ahmad 《应用数学和力学(英文版)》2007,28(7):901-906
In account of the famous Cebysev inequality, a rich theory has appeared in the literature. We establish some new weighted Cebysev type integral inequalities. Our proofs are of independent interest and provide new estimates on these types of inequalities. 相似文献
16.
Syed Qaiser Shah Muhammad Rafiullah Khan 《Journal of Radioanalytical and Nuclear Chemistry》2011,288(2):423-428
In the present study synthesis of the 99mTc?CCNN complex and its efficacy as a prospective Staphylococcus aureus (S. aureus) infection imaging agent was assessed. The 99mTc?CCNN complex was characterized in terms of stability in saline, serum, in vitro binding with S. aureus and in vivo percent absorption in male Wister rats (MWR) infected with live and heat killed S. aureus. Radiochemically the 99mTc?CCNN complex showed stable behavior in saline and serum at different intervals. At 30 min after reconstitution the complex showed maximum radiochemical purity (RCP) yield of 97.55 ± 0.22%. The RCP yield decreased to 90.50 ± 0.18% within 240 min. In serum, 18.15% unwanted side product was appeared within 16 h of the incubation. In vitro saturated binding with S. aureus was observed at different intervals with a 62.00% maximum at 90 min. Normal percent in vivo uptake was observed in MWR artificially infected with live S. aureus with a five times higher in the infected muscle as compared to the inflamed and normal muscles. No difference in the percent uptake of the complex in MWR infected with heat killed S. aureus in the infected, inflamed and normal muscles were observed. Based on the promising in vitro and in vivo radiochemical and biological characteristics, we recommend the 99mTc?CCNN complex for in vivo localization of the S. aureus infectious foci. 相似文献
17.
Arif Rafiq 《Rendiconti del Circolo Matematico di Palermo》2011,60(3):455-461
Let K be a nonempty, closed and convex subset of a real Banach space E. Let T:K→K be a strictly pseudocontractive map. For a fixed x 0∈K, define a sequence {x n } by x n+1=(1?α n )x n +α n Tx n , where {α n } is a real sequence defined in [0,1] satisfying the following conditions (i) $\sum_{n=0}^{\infty }\alpha _{n}=\infty $ , (ii) lim? n→∞ α n =0. Then lim?inf? n→∞‖x n ?Tx n ‖=0. If, in addition, T is demicompact, then {x n } converges strongly to some fixed point of T. Remark 8 is important. 相似文献
18.
Muhammad Khurram Tufail Adeel Ahmed Muhammad Rafiq Muhammad Asif Nawaz Syed Shoaib Ahmad Shah Manzar Sohail Muhammad Sufyan Javed Tayyaba Najam Raed H. Althomali Mohammed M. Rahman 《Chemical record (New York, N.Y.)》2024,24(1):e202300155
In recent years, flexible and wearable electronics such as smart cards, smart fabrics, bio-sensors, soft robotics, and internet-linked electronics have impacted our lives. In order to meet the requirements of more flexible and adaptable paradigm shifts, wearable products may need to be seamlessly integrated. A great deal of effort has been made in the last two decades to develop flexible lithium-ion batteries (FLIBs). The selection of suitable flexible materials is important for the development of flexible electrolytes self-supported and supported electrodes. This review is focused on the critical discussion of the factors that evaluate the flexibility of the materials and their potential path toward achieving the FLIBs. Following this analysis, we present how to evaluate the flexibility of the battery materials and FLIBs. We describe the chemistry of carbon-based materials, covalent-organic frameworks (COFs), metal-organic frameworks (MOFs), and MXene-based materials and their flexible cell design that represented excellent electrochemical performances during bending. Furthermore, the application of state-of-the-art solid polymer and solid electrolytes to accelerate the development of FLIBs is introduced. Analyzing the contributions and developments of different countries has also been highlighted in the past decade. In addition, the prospects and potential of flexible materials and their engineering are also discussed, providing the roadmap for further developments in this fast-evolving field of FLIB research. 相似文献
19.
A. Vijaya Bhaskar Reddy Rehan Rafiq Aqeel Ahmad Abdulhalim Shah Maulud Muhammad Moniruzzaman 《Molecules (Basel, Switzerland)》2022,27(22)
In the current study, we have synthesized an imidazolium based cross-linked polymer, namely, 1-vinyl-3-ethylimidazolium bis(trifluoromethylsulfonyl)imide (poly[veim][Tf2N]-TRIM) using trimethylolpropane trimethacrylate as cross linker, and demonstrated its efficiency for the removal of two extensively used ionic dyes—methylene blue and orange-II—from aqueous systems. The detailed characterization of the synthesized poly[veim][Tf2N]-TRIM was performed with the help of 1H NMR, TGA, FT-IR and FE-SEM analysis. The concentration of dyes in aqueous samples before and after the adsorption process was measured using an UV-vis spectrophotometer. The process parameters were optimised, and highest adsorption was obtained at a solution pH of 7.0, adsorbent dosage of 0.75 g/L, contact time of 7 h and dye concentrations of 100 mg/L and 5.0 mg/L for methylene blue and orange-II, respectively. The adsorption kinetics for orange-II and methylene blue were well described by pseudo-first-order and pseudo–second-order models, respectively. Meanwhile, the process of adsorption was best depicted by Langmuir isotherms for both the dyes. The highest monolayer adsorption capacities for methylene blue and orange-II were found to be 1212 mg/g and 126 mg/g, respectively. Overall, the synthesized cross-linked poly[veim][Tf2N]-TRIM effectively removed the selected ionic dyes from aqueous samples and provided >90% of adsorption efficiency after four cycles of adsorption. A possible adsorption mechanism between the synthesised polymeric adsorbent and proposed dyes is presented. It is further suggested that the proposed ionic liquid polymer adsorbent could effectively remove other ionic dyes and pollutants from contaminated aqueous systems. 相似文献
20.
In this study, we developed an algorithm to find the homomorphisms of the Picard group \(\textit{PSL}(2,Z[i])\) into a finite group G. This algorithm is helpful to find a homomorphism (if it is possible) of the Picard group to any finite group of order less than 15! because of the limitations of the GAP and computer memory. Therefore, we obtain only five alternating groups \( A_{n}\), where \(n=5,6,9,13\) and 14 are quotients of the Picard group. In order to extend the degree of the alternating groups, we use coset diagrams as a tool. In the end, we prove our main result with the help of three diagrams which are used as building blocks and prove that, for \(n\equiv 1,5,6(\mathrm { mod}\, 8)\), all but finitely many alternating groups \(A_{n}\) can be obtained as quotients of the Picard group \(\textit{PSL}(2,Z[i])\). A code in Groups Algorithms Programming (GAP) is developed to perform the calculation. 相似文献