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851.
Md. Sahadat Hossain Muhammad B. Uddin Md. Razzak A. M. Sarwaruddin Chowdhury 《辐射效应与固体损伤》2017,172(11-12):904-914
Composites were prepared successfully by compression molding technique using jute fabrics (reinforcing agent) and polypropylene (matrix). Jute fabrics were treated with disaccharide (sucrose) solution and composites were fabricated with the treated fabric and polypropylene. The fiber content of the prepared composites was 40% by weight. It was found that the sucrose (2% solution) decreased the tensile strength (TS) and elongation at break about 6% and 37%, respectively, but tensile modulus and impact strength improved about 27% and 32%, respectively. When gamma radiation was applied through the untreated and treated composites the mechanical properties were improved much higher in non-treated Jute/PP-based composites than that of sucrose treated composites. For 5.0?kGy gamma dose the highest mechanical properties were observed for non-treated composites. At 5.0?kGy gamma dose the improvement of TS was 14% and 2% for non-treated and sucrose treated composites, respectively. The water uptake property of the sucrose treated composites was performed up to 10 days and composites absorbed 18% water. The functional groups of the both composites were analyzed by Fourier transform infrared spectroscopy machine. The scanning electron microscopic images of the both composites were taken for the surface and fiber adhesion analysis. 相似文献
852.
Mir Mehedi Faruk Md. Muktadir Rahman Dwaipayan Debnath Md. Sakhawat Hossain Himel 《理论物理通讯》2016,65(4):465-468
Energy fluctuation of ideal Fermi gas trapped under generic power law potential U=Σ_(i=1)~d c_i|x_i/a_i|~(n_i) has been calculated in arbitrary dimensions.Energy fluctuation is scrutinized further in the degenerate limit μK_B T with the help of Sommerfeld expansion.The dependence of energy fluctuation on dimensionality and power law potential is studied in detail.Most importantly our general result can not only exactly reproduce the recently published result regarding free and harmonically trapped ideal Fermi gas in d =3 but also can describe the outcome for any power law potential in arbitrary dimension. 相似文献
853.
P.V. Adhyapak M. Islam R.C. Aiyer U.P. Mulik Y.S. Negi D.P. Amalnerkar 《Journal of Crystal Growth》2008,310(11):2923-2927
Meta-nitroaniline (m-NA) is one of the organic single crystals extensively studied due to its high non-linear effect. m-NA is also known to exhibit comparable or even better non-linear optical (NLO) properties than known inorganic materials. In this paper, we report development of m-NA single crystals by solution growth technique using different solvent systems. The size of the single crystal varies depending on solvent. The highest average crystal size acquired was 10 mm×5 mm×5 mm using methyl ethyl ketone and acetone as solvent. These single crystals were characterized using various physico-chemical techniques such as XRD and scanning electron microscopy (SEM). The developed crystals were subsequently coated with recycled polystyrene (Re-PS) (1, 2, 5 and 10 wt% concentrations) to study the effect of polymer coating on the second harmonic generation (SHG) properties of the single crystals. The purpose of polymer coating on m-NA single crystal is to improve surface morphology of crystal (i.e. it makes surface smooth) and to enhance power handling capacity for pulse laser of a crystal which, in turn, improves the SHG intensity. The optimum percentage of coating was determined for the m-NA single crystals obtained from different solvent systems. Furthermore, the polymer coating also plays key role in preventing the degradation of the m-NA crystal (well-known as highly sublime material) and ultimately increasing the shelf life of the crystal for its device application. 相似文献
854.
Mananga ES Hsu CD Ishmael S Islam T Boutis GS 《Journal of magnetic resonance (San Diego, Calif. : 1997)》2008,193(1):10-22
In this work, we investigate the accuracy of controlling spin I=1, 3/2 and 5/2 spin systems by average Hamiltonian theory. By way of example, we consider a simple two-pulse echo sequence and compare this perturbation scheme to a numerical solution of the Von Neumann equation. For the different values of I, we examine this precision as a function of the quadrupolar coupling as well as various experimental parameters such as the pulse spacing and pulse width. Experiments and simulations on I=3/2 and I=5/2 spin systems are presented that highlight a spectral artifact introduced due to finite pulse widths as predicted by average Hamiltonian theory. The control of these spin systems by this perturbation scheme is considered by investigating a phase cycling scheme that suppresses these artifacts to zeroth-order of the Magnus expansion. 相似文献
855.
Abdullah Mohammed Al-Majid M. Ali Mohammad Shahidul Islam Saeed Alshahrani Abdullah Saleh Alamary Sammer Yousuf M. Iqbal Choudhary Assem Barakat 《Molecules (Basel, Switzerland)》2021,26(20)
A new series of di-spirooxindole analogs, engrafted with oxindole and cyclohexanone moieties, were synthesized. Initially, azomethine ylides were generated via reaction of the substituted isatins 3a–f (isatin, 3a, 6-chloroisatin, 3b, 5-fluoroisatin, 3c, 5-nitroisatin, 3d, 5-methoxyisatin, 3e, and 5-methylisatin, 3f, and (2S)-octahydro-1H-indole-2-carboxylic acid 2, in situ azomethine ylides reacted with the cyclohexanone based-chalcone 1a–f to afford the target di-spirooxindole compounds 4a–n. This one-pot method provided diverse structurally complex molecules, with biologically relevant spirocycles in a good yields. All synthesized di-spirooxindole analogs, engrafted with oxindole and cyclohexanone moieties, were evaluated for their anticancer activity against four cancer cell lines, including prostate PC3, cervical HeLa, and breast (MCF-7, and MDA-MB231) cancer cell lines. The cytotoxicity of these di-spirooxindole analogs was also examined against human fibroblast BJ cell lines, and they appeared to be non-cytotoxic. Compound 4b was identified as the most active member of this series against prostate cancer cell line PC3 (IC50 = 3.7 ± 1.0 µM). The cyclohexanone engrafted di-spirooxindole analogs 4a and 4l (IC50 = 7.1 ± 0.2, and 7.2 ± 0.5 µM, respectively) were active against HeLa cancer cells, whereas NO2 substituted isatin ring and meta-fluoro-substituted (2E,6E)-2,6-dibenzylidenecyclohexanone containing 4i (IC50 = 7.63 ± 0.08 µM) appeared to be a promising agent against the triple negative breast cancer MDA-MB231 cell line. To explore the plausible mechanism of anticancer activity of di-spirooxindole analogs, molecular docking studies were investigated which suggested that spirooxindole analogs potentially inhibit the activity of MDM2. 相似文献
856.
In-Soo You Subham Sharma Ailyn Fadriquela Johny Bajgai Thuy Trinh Thi Md. Habibur Rahman Jaeyong Sung Hwang-Un Kwon So-Yeon Lee Cheol-Su Kim Kyu-Jae Lee 《Molecules (Basel, Switzerland)》2021,26(21)
Oxidative stress plays a crucial role in the development of airway diseases. Recently, hydrogen (H2) gas has been explored for its antioxidant properties. This study investigated the role of H2 gas in oxidative stress-induced alveolar and bronchial airway injury, where A549 and NCI-H292 cells were stimulated with hydrogen peroxide (H2O2) and lipopolysaccharide (LPS) in vitro. Results show that time-dependent administration of 2% H2 gas recovered the cells from oxidative stress. Various indicators including reactive oxygen species (ROS), nitric oxide (NO), antioxidant enzymes (catalase, glutathione peroxidase), intracellular calcium, and mitogen-activated protein kinase (MAPK) signaling pathway were examined to analyze the redox profile. The viability of A549 and NCI-H292 cells and the activity of antioxidant enzymes were reduced following induction by H2O2 and LPS but were later recovered using H2 gas. Additionally, the levels of oxidative stress markers, including ROS and NO, were elevated upon induction but were attenuated after treatment with H2 gas. Furthermore, H2 gas suppressed oxidative stress-induced MAPK activation and maintained calcium homeostasis. This study suggests that H2 gas can rescue airway epithelial cells from H2O2 and LPS-induced oxidative stress and may be a potential intervention for airway diseases. 相似文献
857.
858.
S. M. Abu Nayem Santa Islam Mostafa Mohamed Syed Shaheen Shah A. J. Saleh Ahammad Md. Abdul Aziz 《Chemical record (New York, N.Y.)》2024,24(1):e202300005
Aluminum-air batteries (AABs) are regarded as attractive candidates for usage as an electric vehicle power source due to their high theoretical energy density (8100 Wh kg−1), which is considerably higher than that of lithium-ion batteries. However, AABs have several issues with commercial applications. In this review, we outline the difficulties and most recent developments in AABs technology, including electrolytes and aluminum anodes, as well as their mechanistic understanding. First, the impact of the Al anode and alloying on battery performance is discussed. Then we focus on the impact of electrolytes on battery performances. The possibility of enhancing electrochemical performances by adding inhibitors to electrolytes is also investigated. Additionally, the use of aqueous and non-aqueous electrolytes in AABs is also discussed. Finally, the challenges and potential future research areas for the advancement of AABs are suggested. 相似文献
859.
Mst. Sharmin Sultana Shimu Shafi Mahmud Trina Ekwati Tallei Saad Ahmed Sami Ahmad Akroman Adam Uzzal Kumar Acharjee Gobindo Kumar Paul Talha Bin Emran Shahriar Zaman Md. Salah Uddin Md. Abu Saleh Sultan Alshehri Mohammed M Ghoneim Maha Alruwali Ahmad J. Obaidullah Nabilah Rahman Jui Junghwan Kim Bonglee Kim 《Molecules (Basel, Switzerland)》2022,27(3)
860.
Rashid Waseem Anas Shamsi Taj Mohammad Md. Imtaiyaz Hassan Syed Naqui Kazim Anis Ahmad Chaudhary Hassan Ahmed Rudayni Mohammed Al-Zharani Faizan Ahmad Asimul Islam 《Molecules (Basel, Switzerland)》2022,27(3)
A sedentary lifestyle or lack of physical activity increases the risk of different diseases, including obesity, diabetes, heart diseases, certain types of cancers, and some neurological diseases. Physical exercise helps improve quality of life and reduces the risk of many diseases. Irisin, a hormone induced by exercise, is a fragmented product of FNDC5 (a cell membrane protein) and acts as a linkage between muscles and other tissues. Over the past decade, it has become clear that irisin is a molecular mimic of exercise and shows various beneficial effects, such as browning of adipocytes, modulation of metabolic processes, regulation of bone metabolism, and functioning of the nervous system. Irisin has a role in carcinogenesis; numerous studies have shown its impact on migration, invasion, and proliferation of cancer cells. The receptor of irisin is not completely known; however, in some tissues it probably acts via a specific class of integrin receptors. Here, we review research from the past decade that has identified irisin as a potential therapeutic agent in the prevention or treatment of various metabolic-related and other diseases. This article delineates structural and biochemical aspects of irisin and provides an insight into the role of irisin in different pathological conditions. 相似文献