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81.
Various two vertex sharing macropolyhedral boranes were computed at the B3LYP/6-311 + G**//B3LYP/6-31G* level of theory to determine the preferred fragments for the thermodynamically most stable isomers. These are nido-10 and arachno-9 vertex fragments for neutral macropolyhedral boranes. The thermodynamically most stable isomers of the nido:nido-, arachno:nido- and arachno:arachno-macropolyhedral borane classes are structurally related to each other by the successive removal of one open face vertex as in the case of simple polyhedral boranes. For these classes, the stabilities of the thermodynamically most stable macropolyhedra relative to isomeric simple polyhedra follow similar trends with respect to the number of skeletal electrons. 相似文献
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Fatimah Saeed Aldughaylibi Muhammad Asam Raza Sumaira Naeem Humera Rafi Mir Waqas Alam Basma Souayeh Mohd Farhan Muhammad Aamir Noushi Zaidi Tanveer Ahmad Mir 《Molecules (Basel, Switzerland)》2022,27(18)
This study was designed to check the potential of secondary metabolites of the selected plants; Citrullus colocynthis, Solanum nigrum, Solanum surattense, Calotropis procera, Agave americana, and Anagallis arvensis for antioxidant, antibacterial, antifungal, and antidiabetic agents. Plant material was soaked in ethanol/methanol to get the crude extract, which was further partitioned via solvent extraction technique. GCMS and FTIR analytical techniques were applied to check the compounds responsible for causing antioxidant, antimicrobial, and antidiabetic activities. It was concluded that about 80% of studied extracts/fractions were active against α-amylase, ranging from 43 to 96%. The highest activity (96.63%) was exhibited by butanol fractions of A. arvensis while the least response (43.65%) was shown by the aqueous fraction of C. colocynthis and the methanol fraction of fruit of S. surattense. The highest antioxidant activity was shown by the ethyl acetate fraction of Anagallis arvensis (78.1%), while aqueous as well as n-hexane fractions are the least active throughout the assay. Results showed that all tested plants can be an excellent source of natural products with potential antimicrobial, antioxidant, and antidiabetic potential. The biological response of these species is depicted as a good therapeutic agent, and, in the future, it can be encapsulated for drug discovery. 相似文献
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Amjad Sohail Zaheer Abbas Rizwan Ahmed Aamir Shahzad Naeem Akhtar Jia-Xing Peng 《Annalen der Physik》2023,535(6):2300087
Gaussian quantum steering is a type of quantum correlation in which two entangled states exhibit asymmetry. An efficient theoretical proposal is presented for the control of quantum steering and enhancement of entanglement in a Laguerre–Gaussian (LG) cavity optomechanical system. The system contains two rotating mirrors and a coherently driven optical parametric amplifier (OPA). The numerical results show significantly improved mirror-mirror and mirror-cavity entanglements by controlling the system parameters such as parametric gain, parametric phase, and the frequency of the two rotating mirrors. In addition to bipartite entanglement, our system also exhibits mirror-cavity-mirror tripartite entanglement as well. Another intriguing finding is the control of quantum steering, for which several results were obtained by investigating it for various system parameters. It is shown that the steering directivity is primarily determined by the frequency of two rotating mirrors. Furthermore, for two rotating mirrors, quantum steering is found to be asymmetric both one-way and two-way. Therefore, it can be asserted that the current proposal may help in the understanding of non-local correlations and entanglement verification tasks. 相似文献
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M. Umar Farooq Mubasher Jamil Muneer A. Rashid 《International Journal of Theoretical Physics》2010,49(9):2278-2287
We consider the new agegraphic dark energy model with the help of the quantum corrections to the entropy-area relation in
the setup of loop quantum gravity. Employing this new form of dark energy so called entropy-corrected new agegraphic dark
energy (ECNADE), we investigate the model of interacting dark energy and derive its equation of state (EoS). We study the
correspondence between the K-essence, tachyon and dilaton scalar fields with the interacting (ECNADE)in the non-flat FRW universe.
Moreover, we reconstruct the corresponding scalar potentials which describe the dynamics of the scalar field. 相似文献
89.
Obaid-ur-Rahman Abid Muhammad Farooq Ibad Asad Ali Nasim Hasan Rama Peter Langer 《Tetrahedron letters》2010,51(12):1541-721
The palladium(0)-catalyzed Suzuki cross-coupling reaction of the bis(triflates) of phenyl 1,4-dihydroxy-2-naphthoate afforded various 1,4-diaryl-2-naphthoates. The reactions proceeded with very good site-selectivity. Due to electronic reasons, the first attack occurred at the sterically more hindered position C-1. 相似文献
90.
Pathak A Singh SK Biabani MA Kulshreshtha DK Puri SK Srivastava S Kundu B 《Combinatorial chemistry & high throughput screening》2002,5(3):241-248
Triterpenoid-based scaffolds betulinic acid (1a) and ursolic acid (1b), have been used for the generation of combinatorial libraries in parallel format using solid phase organic synthesis method. These templates have the potential for the synthesis and amplification of triterpenoid-based compounds with one and two-point diversity. This has been demonstrated by the synthesis of two small libraries comprising 18 derivatives each of betulinic acid and ursolic acid with structural diversity at C-3 and C-28 positions. The primary screening of antimalarial activity of these libraries against P. falciparum in vitro led to the identification of four compounds with 5 fold increase in the activity compared to betulinic and ursolic acids. 相似文献