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991.
992.
993.
In this work, the magnetohydrodynamics (MHD) natural convection heat transfer problem inside a porous medium filled with inclined rectangular enclosures is investigated numerically. The boundary conditions selected on the enclosure are two adiabatic and two isothermal walls. The governing equations, continuity, and Forchheimer extension of the Darcy law and energy are transformed into dimensionless forms by using a set of suitable variables, and then solved by using a finite difference scheme. The governing parameters are the magnetic influence number, the Darcy Rayleigh number, the inclination angle, and the aspect ratio of the enclosure. It is found that the magnetic influence number and the inclination angle have pronounced effects on the fluid flow and heat transfer in porous media-filled enclosures. 相似文献
994.
995.
A new polymeric resin with glucose sulfonamide functions has been prepared for the extraction of boric acid. This poly (styryl sulfonamide) based resin has been demonstrated to be an efficient sorbent for the removal of boron. The resin had a boron loading capacity of 2.365 mmol.g−1 and showed reasonably rapid sorption ability. Splitting of sorbed boron can be achieved by simple acid leaching (2M H2SO4). 相似文献
996.
Mehmet Akkurt Sema
ztürk Hakan Üngren Mustafa Samac Hoong‐Kun Fun Yunus Akamur 《Acta Crystallographica. Section C, Structural Chemistry》2003,59(10):o598-o600
The title compound, C24H25NO7, is a racemic mixture of 2,3‐dihydro‐1H‐pyrrol‐3‐ones. It crystallizes in the triclinic system, space group P1, with Z = 2. The asymmetric unit contains two enantiomorphic molecules and the structure is stabilized by hydrogen‐bond contacts. 相似文献
997.
998.
Shujaat Ahmad Manzoor Ahmad Mazen Almehmadi Syed Adnan Ali Shah Farman Ali Khan Nasir Mehmood Khan Asifullah Khan Zainab Mustafa Halawi Hanif Ahmad 《Molecules (Basel, Switzerland)》2022,27(14)
This study reports the isolation of three new C20 diterpenoid alkaloids, Chitralinine A–C (1–3) from the aerial parts of Delphinium chitralense. Their structures were established on the basis of latest spectral techniques and single crystal X-rays crystallographic studies of chitralinine A described basic skeleton of these compounds. All the isolated Compounds (1–3) showed strong, competitive type inhibition against acetylcholinesterase (AChE) and butyrylcholinesterase (BChE) in comparison to standard allanzanthane and galanthamine however, chitralinine-C remained the most potent with IC50 value of 11.64 ± 0.08 μM against AChE, and 24.31 ± 0.33 μM against BChE, respectively. The molecular docking reflected a binding free energy of −16.400 K Cal-mol−1 for chitralinine-C, having strong interactions with active site residues, TYR334, ASP72, SER122, and SER200. The overall findings suggest that these new diterpenoid alkaloids could serve as lead drugs against dementia-related diseases including Alzheimer’s disease. 相似文献
999.
Qudsia Sarwer Muhammad Shoaib Amjad Ansar Mehmood Zakia Binish Ghazala Mustafa Atikah Farooq Mirza Faisal Qaseem Fozia Abasi Jos Manuel Prez de la Lastra 《Molecules (Basel, Switzerland)》2022,27(21)
Nanotechnology is the study and control of materials at length scales between 1 and 100 nanometers (nm), where incredible phenomena enable new applications. It affects all aspects of human life and is the most active research topic in modern materials science. Among the various metallic nanoparticles used in biomedical applications, silver nanoparticles (AgNPs) are among the most important and interesting nanomaterials. The aim of this study was to synthesize AgNPs from the leaf extract of Myrsine africana to investigate their antibacterial, antioxidant, and phytotoxic activities. When the leaf extract was treated with AgNO3, the color of the reaction solution changed from light brown to dark brown, indicating the formation of AgNPs. The UV-visible spectrum showed an absorption peak at 438 nm, confirming the synthesis of AgNPs. Scanning electron microscopy (SEM) showed that the AgNPs were spherical and oval with an average size of 28.32 nm. Fourier transform infrared spectroscopy confirms the presence of bio-compound functional groups on the surface of the AgNPs. The crystalline nature of the AgNPs was confirmed by XRD pattern. These biosynthesized AgNPs showed pronounced antibacterial activity against Gram-positive and Gram-negative bacteria, with higher inhibitory activity against Escherichia coli. At 40 µg/mL AgNPs, the highest antioxidant activity was obtained, which was 57.7% and an IC50 value of 77.56 µg/mL. A significant positive effect was observed on all morphological parameters when AgNPs were applied to wheat seedlings under constant external conditions at the different concentrations. The present study provides a cost-effective and environmentally friendly method for the synthesis of AgNPs, which can be effectively used in the field of therapeutics, as antimicrobial and diagnostic agents, and as plant growth promoters. 相似文献
1000.
Mustafa M. Aldfer Ibrahim A. Alfayez Hamza A. A. Elati Nilanjana Gayen Ehab Kotb Elmahallawy Ana Milena Murillo Sabrina Marsiccobetre Serge Van Calenbergh Ariel M. Silber Harry P. de Koning 《Molecules (Basel, Switzerland)》2022,27(22)
Among the scarce validated drug targets against Chagas disease (CD), caused by Trypanosoma cruzi, the parasite’s nucleoside salvage system has recently attracted considerable attention. Although the trypanocidal activity of tubercidin (7-deazapurine) has long been known, the identification of a class of 7-substituted tubercidin analogs with potent in vitro and in vivo activity and much-enhanced selectivity has made nucleoside analogs among the most promising lead compounds against CD. Here, we investigate the recently identified TcrNT2 nucleoside transporter and its potential role in antimetabolite chemotherapy. TcrNT2, expressed in a Leishmania mexicana cell line lacking the NT1 nucleoside transporter locus, displayed very high selectivity and affinity for thymidine with a Km of 0.26 ± 0.05 µM. The selectivity was explained by interactions of 2-oxo, 4-oxo, 5-Me, 3′-hydroxy and 5′-hydroxy with the transporter binding pocket, whereas a hydroxy group at the 2′ position was deleterious to binding. This made 5-halogenated 2′-deoxyuridine analogues good substrates but 5-F-2′-deoxyuridine displayed disappointing activity against T. cruzi trypomastigotes. By comparing the EC50 values of tubercidin and its 7-substituted analogues against L. mexicana Cas9, Cas9ΔNT1 and Cas9ΔNT1+TcrNT2 it was shown that TcrNT2 can take up tubercidin and, at a minimum, a subset of the analogs. 相似文献