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101.
Arshad Sadiqa Khan Majid Hussain Iqtadar 《International Journal of Theoretical Physics》2021,60(9):3631-3650
International Journal of Theoretical Physics - The use of digital contents has increased tremendously in this modern era. In fact, people spend more time on internet than ever which urged the... 相似文献
102.
M. N. Arshad O. Şahin M. Zia-ur-Rehman I. U. Khan A. M. Asiri H. M. Rafique 《Journal of Structural Chemistry》2013,54(2):437-442
The title compound, 4-hydroxy-2H-1,2-benzothiazine-3-carbohydrazide 1,1-dioxide-oxalohydrazide (1:1), is determined using X-ray diffraction techniques and the molecular structure is also optimized at the B3LYP/6-31G(d,p) level using density functional theory (DFT). The asymmetric unit consists of four independent molecules. The oxalohydrazide molecules have the centre of symmetry at the mid-point of the central C-C bond. Each thiazine ring adopts a half-chair conformation. Intermolecular C-H...O, N-H...O and N-H...N hydrogen bonds produce R 2 2 (10), R 2 2 (13), R 3 3 (12) and R 3 3 (15) rings, which lead to one-dimensional polymeric chains. An extensive three-dimensional supramolecular network of N-H...N, N-H...O, C-H...O and O-H...O hydrogen bonds is responsible for crystal structure stabilization. 相似文献
103.
There is always need for secure transmission of information and simultaneously compact-size photonic circuits. This can be achieved if surface plasmon-polaritons(SPPs) are used as source of information, and the reduced hacking as the transmission phenomenon. In this article, an SPP-based reduced hacking scheme is presented at interface between atomic medium and metallic conductor. The SPP propagation is manipulated with conductivity of the metal. The delay or advance of the SPP is found to create nanosecond time gap which can be used for storing and sending the information safely. The reduced hacking is further modified with conductivity of the metal and the control parameters of the atomic medium. 相似文献
104.
Theoretical and Mathematical Physics - We explore conformal Ricci collineations (CRCs) for static space–times with maximal symmetric transverse spaces. Solving the CRC equations in the... 相似文献
105.
Lgaz Hassane Chaouiki Abdelkarim Albayati Mustafa R. Salghi Rachid El Aoufir Yasmina Ali Ismat H. Khan Mohammad I. Mohamed Shaaban K. Chung Ill-Min 《Research on Chemical Intermediates》2019,45(4):2269-2286
Research on Chemical Intermediates - Mild steel corrosion in HCl solution is an example of corrosion in acidic mediums. The ongoing research efforts to develop novel environmentally friendly... 相似文献
106.
We develop a fully calibrated positive mathematical programming model for Hawaii's local food systems—which captures the production and the consumer sides of the market. Then we use the model to assess two proposed policies—a general excise tax (GET) exemption on locally produced foods, and an investment in agricultural infrastructure. For the GET exemption case, our results indicate an economic gain of $118 per $100 cost. On the other hand, an investment in 1,200 acres of land injected to support local production may generate an economic gain of up to $357 per $100 annual cost of the investment. However, these estimates should be considered preliminary, and thus viewed with caution. Although the model is used to capture Hawaii's local food systems, we believe that our model is generalizable and can be adopted by other economies to assess their respective food localization policies. Recommendations for Resource Managers
- Local food policies need to be based on quantitative terms instead of mere armchair speculation because often their potential outcomes may vary significantly.
- The current modeling framework demonstrates the potential of using positive mathematical programming (PMP) in capturing the intricacies of local food systems. However, this exploratory exercise should be viewed as preliminary in nature and the ensuing results were taken with caution because many important factors such as labor availability may have been left out.
- Thus, further model refinements are necessary to better capture the complexities of local food systems such as farm heterogeneity, availability of farm labor, water availability, and interisland transportation of farm products in the case of Hawaii.
107.
Meena Kumari Upendra Kumar Singh Abbul Bashar Khan Maqsood Ahmad Malik 《Journal of Dispersion Science and Technology》2018,39(10):1462-1468
The effect of bovine serum albumin on the surface properties of IL-type gemini surfactant ([C10-4-C10im]Br2), have been investigated by surface tension method. The critical micelle concentration (CMC) as a function of BSA concentrations at various temperatures was investigated. The CMC of [C10-4-C10im]Br2 increases with increasing the concentration of BSA as well as the temperature of the system. The interfacial parameters viz; maximum surface excess concentration (Γmax), the minimum area per molecule (Amin), and surface pressure at CMC (Πcmc) were calculated. In addition, thermodynamic parameters of adsorption and micellization were evaluated by using surface tension data. The results indicated that the binding of [C10-4-C10im]Br2 to BSA is spontaneous and exothermic in nature. The process is entropy driven and hydrophobic interactions are the major driving forces. 相似文献
108.
Aftab Aslam Parwaz Khan Anish Khan Abdullah M Asiri Heba A Kashmery 《Russian Journal of Physical Chemistry B, Focus on Physics》2018,12(3):412-421
The oxidation of Rizatriptan by diperiodatoargentate(III) has been studied by spectrophotometry at neutral pH. The kinetics of the reaction of Rizatriptan has been shown to principle of non-complementary oxidation steps. The initial step involves the deprotonated of the diperiodatoargentate(III) with the alkali; this rearranges during the displacement of a ligand to give free periodate and takes up another ligand monoperiodateargentate(III), combines with a substrate to endow with an intermediate complex which decomposes within a slow step to provide the final product in the following step with a first-order rate constant. The main product was identified by spot test, Fourier- transform infrared spectroscopy, Nuclear magnetic resonance and Liquid chromatography-mass spectrometry spectrum. A conceivable mechanism including pre equilibrium of adducts development between the complex and reductant was planned from the kinetics study. The rate conditions got from system can clarify all exploratory phenomena, and the activation parameters alongside rate constants of the rate determining step were ascertained. 相似文献
109.
Tris(2‐aminoethyl)amine‐based ferrocene‐terminated dendrimers as burning rate catalysts for ammonium perchlorate‐based propellant decomposition 下载免费PDF全文
Zain‐ul‐Abdin Li Wang Haojie Yu Rizwan Ullah Khan Raja Summe Ullah Muhammad Haroon 《应用有机金属化学》2018,32(4)
Ferrocene‐based derivatives show potential application as burning rate catalysts (BRCs) for solid composite propellants. However, migration problems of simple ferrocene‐based derivatives limit their application as BRCs in solid composite propellants. To overcome the migration problems of ferrocene‐based BRCs and to enhance the burning rate of ammonium perchlorate (AP)‐based propellants, zero‐ to second‐generation tris(2‐aminoethyl)amine‐based ferrocene‐terminated dendrimers (G0, G1 and G2) were synthesized. The structures of G0, G1 and G2 were confirmed using 1H NMR, Fourier transform infrared and UV–visible spectroscopies. The electrochemical behavior of G0, G1 and G2 was investigated using cyclic voltammetry. It was found that G0, G1 and G2 showed redox behavior due to the presence of ferrocene and this redox behavior was diffusion controlled over the investigated scan range. The burning rate catalytic effect of G0, G1 and G2 on thermal decomposition of AP was investigated using thermogravimetry and differential thermogravimetry. G0, G1 and G2 showed good catalytic effect on the thermal decomposition of AP. Anti‐migration studies showed that migration of G0, G1 and G2 was much slower than that of 2,2‐bis(ethylferrocenyl)propane (catocene) and ferrocene. 相似文献
110.