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81.
Muhammad Tariq Saqib Ali Muhammad Nawaz Tahir Nasir Khalid Jafir Hussain Shirazi 《Journal of the Iranian Chemical Society》2014,11(3):839-846
A series of six organotin(IV) carboxylates [Me2SnL2] (1), [n-Bu2SnL2] (2), [n-Oct2SnL2] (3), [Me3SnL] (4), n-Bu3SnL (5) and [Ph3SnL] (6), where L = 3-(4-cyanophenyl) acrylic acid have been synthesized and characterized by elemental analysis, FT-IR and NMR (1H, 13C). The complex (4) was also analyzed by single crystal X-ray analysis which showed distorted trigonal bipyramidal geometry with polymeric bridging behavior. The complexes 1–6 were screened for antimicrobial activities and cytotoxicity. The results showed significant activity with few exceptions. The catalytic activity of complexes was assessed in transesterification reaction of Brassica campestris oil (triglycerides) to produce biodiesel (fatty acid methyl esters). The results showed that triorganotin(IV) complexes exhibited good catalytic activity than their di-analogues. 相似文献
82.
Mohammad Vatankhah‐Varnoosfaderani Amin GhavamiNejad Saud Hashmi Florian J. Stadler 《Macromolecular rapid communications》2015,36(5):447-452
Copolymers of N‐isopropylacrylamide (NIPAM) and dopamine methacrylate can establish a reversible, self‐healing 3D network in aprotic solvents based on hydrogen bonding. The reactivity and hydrogen bonding formation of catechol groups in copolymer chains are studied by UV–vis and 1H NMR spectroscopy, while reversibility from sol to gel and inverse as well as self‐healing properties are tested rheologically. The produced reversible organogel can self‐encapsulate physically interacting or chemically bonded solutes such as drugs due to thermosensitivity of the used copolymer. This system offers dual‐targeted and controlled drug delivery and release—by slowing down release kinetics by supramolecular bonding of the drug and by reducing diffusion rates due to modulus increase.
83.
Revathy Deivasigamani Nur Shahira Abdul Nasir Mohd Ambri Mohamed Muhamad Ramdzan Buyong 《Electrophoresis》2022,43(4):609-620
This article describes a dielectrophoresis (DEP)-based simulation and experimental study of human epidermal keratinocyte (HEK) cells for wounded skin cell migration toward rapid epithelialization. MyDEP is a standalone software designed specifically to study dielectric particles and cell response to an alternating current (AC) electric field. This method demonstrated that negative dielectrophoresis (NDEP) occurs in HEK cells at a wide frequency range in highly conductive medium. The finite element method was used to characterize particle trajectory based on DEP and drag force. The performance of the system was assessed using HEK cells in a highly conductive EpiLife suspending medium. The DEP experiment was performed by applying sinusoidal wave AC potential at the peak-to-peak voltage of 10 V in a tapered aluminum microelectrode array from 100 kHz to 1 MHz. We experimentally observed the occurrence of NDEP, which attracted HEK cells toward the local electric field minima in the region of interest. The DIPP-MotionV software was used to track cell migration in the prerecorded video via an automatic marker and estimate the average speed and acceleration of the cells. The results showed that HEK cell migration was accomplished approximately at 6.43 μm/s at 100 kHz with 10 V, and FDEP caused the cells to migrate and align at the target position, which resulted in faster wound closures because of the application of an electric field frequency to HEK cells in random locations. 相似文献
84.
Sadeghi Mohamad Sadegh Anadalibkhah Naghmeh Ghasemiasl Ramin Armaghani Taher Dogonchi Abdul Sattar Chamkha Ali J. Ali Hafiz Asadi Amin 《Journal of Thermal Analysis and Calorimetry》2022,147(1):1-22
Journal of Thermal Analysis and Calorimetry - The ultimate goal of the present review paper is to summarize and discuss the findings of the most recently published literature on natural convection... 相似文献
85.
Mohammed S. M. Moustafa A. H. El-Sayed H. A. Amin A. S. Haggar A. Tantawy E. S. Haggam R. A. 《Russian Journal of General Chemistry》2022,92(9):1806-1813
Russian Journal of General Chemistry - A highly efficient synthetic methodology for the preparation of 2-thioxocytosine was achieved by the nucleophilic addition of thiourea to... 相似文献
86.
Ghasemiasl Ramin Javadi Mohammad Amin Nezamabadi Morteza Sharifpur Mohsen 《Journal of Thermal Analysis and Calorimetry》2021,144(3):993-1002
Journal of Thermal Analysis and Calorimetry - The selective drug delivery system could be an excellent alternative to fight cancer and pathogens, due to its minimized negative consequences.... 相似文献
87.
We consider a model for magnetic memory that consists of strongly coupled dipolar or antiferromagnetic (AF) pairs with inequivalent perpendicular anisotropy K1 and K2. For appropriate parameter values, determined in this work, they have two inequivalent storage states with zero net magnetic moment. Both analytical and numerical calculations are performed, in some cases yielding different results because of relaxation effects (i.e., a dependence on the damping parameter α). Hysteresis loops for a wide variety of parameter values are obtained, both for the AF case and the dipole case. An Appendix gives analytic results for slightly non-collinear spins in an applied field, which were used to test the numerical results. 相似文献
88.
89.
In this study, secondary structures of sweet potato protein (SPP) after high hydrostatic pressure (HHP) treatment (200–600?MPa) were evaluated and emulsifying properties of emulsions with HHP-treated SPP solutions in different pH values (3, 6, and 9) were investigated. Circular dichroism analysis confirmed the modification of the SPP secondary structure. Surface hydrophobicity increased at pH 3 and decreased at 6 and 9. Emulsifying activity index at pH 6 increased with an increase in pressure, whereas emulsifying stability index increased at pH 6 and 9. Oil droplet sizes decreased, while volume frequency distribution of the smaller droplets increased at pH 3 and 6 with the HHP treatment. Emulsion viscosity increased at pH 6 and 9 and pseudo-plastic flow behaviors were not altered for all emulsions produced with HHP-treated SPP. These results suggested that HHP could modify the SPP structure for better emulsifying properties, which could increase the use of SPP emulsion in the food industry. 相似文献
90.
The independence number of a sparse random graph G(n,m) of average degree d = 2m/n is well‐known to be with high probability, with in the limit of large d. Moreover, a trivial greedy algorithm w.h.p. finds an independent set of size , i.e., about half the maximum size. Yet in spite of 30 years of extensive research no efficient algorithm has emerged to produce an independent set with size for any fixed (independent of both d and n). In this paper we prove that the combinatorial structure of the independent set problem in random graphs undergoes a phase transition as the size k of the independent sets passes the point . Roughly speaking, we prove that independent sets of size form an intricately rugged landscape, in which local search algorithms seem to get stuck. We illustrate this phenomenon by providing an exponential lower bound for the Metropolis process, a Markov chain for sampling independent sets. © 2014 Wiley Periodicals, Inc. Random Struct. Alg., 47, 436–486, 2015 相似文献