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141.
Mohammed A. Huneif Seham M. Alqahtani Alqahtani Abdulwahab Sultan A. Almedhesh Mater H. Mahnashi Muhammad Riaz Najm Ur-Rahman Muhammad Saeed Jan Farhat Ullah Muhammad Aasim Abdul Sadiq 《Molecules (Basel, Switzerland)》2022,27(11)
Diabetes mellitus is a metabolic disorder and is a global challenge to the current medicinal chemists and pharmacologists. This research has been designed to isolate and evaluate antidiabetic bioactives from Fragaria indica. The crude extracts, semi-purified and pure bioactives have been used in all in vitro assays. The in vitro α-glucosidase, α-amylase and DPPH free radical activities have been performed on all plant samples. The initial activities showed that ethyl acetate (Fi.EtAc) was the potent fraction in all the assays. This fraction was initially semi-purified to obtain Fi.EtAc 1–3. Among the semi-purified fractions, Fi.EtAc 2 was dominant, exhibiting potent IC50 values in all the in vitro assays. Based on the potency and availability of materials, Fi.EtAc 2 was subjected to further purification to obtain compounds 1 (2,4-dichloro-6-hydroxy-3,5-dimethoxytoluene) and 2 (2-methyl-6-(4-methylphenyl)-2-hepten-4-one). The two isolated compounds were characterized by mass and NMR analyses. The compounds 1 and 2 showed excellent inhibitions against α-glucosidase (21.45 for 1 and 15.03 for 2 μg/mL), α-amylase (17.65 and 16.56 μg/mL) and DPPH free radicals (7.62 and 14.30 μg/mL). Our study provides baseline research for the antidiabetic bioactives exploration from Fragaria indica. The bioactive compounds can be evaluated in animals-based antidiabetic activity in future. 相似文献
142.
Amir Zada Nauman Ali Muhammad Ateeq Ali M. Huerta-Flores Zahid Hussain Shabana Shaheen Mohib Ullah Sharafat Ali Imran Khan Wajid Ali Muhammad Ishaq Ali Shah Waliullah Khan 《中国化学会会志》2020,67(6):983-989
Energy crises and environmental pollution have sparked tremendous research work to handle their impacts. Herein, we fabricated Au/g-C3N4 nanocomposites to produce H2 and degrade 2,4-dichlorophenol (2,4-DCP) under visible light and at different wavelengths. Interestingly, the optimized photocatalyst generated 114 μmol H2 and degraded 25% 2,4-DCP in 1 hr as compared with 10 μmol H2 generation and 8% 2,4-DCP degradation by pure g-C3N4. This improvement is credited to the extended light absorption and improved charge induction from gold to g-C3N4 even at 590 nm as confirmed from photoluminescence, surface photovoltage, and photoelectrochemical study of the samples. Moreover, the surface catalytic property of g-C3N4 was much improved after loading a proper amount of gold nanoparticles. We hope that this technique to photosensitize semiconductors with noble metal nanoparticles may provide a feasible way to construct surface plasmon resonance-assisted photocatalysts to cope with energy crises and environmental pollution simultaneously. 相似文献
143.
Sulaiman Sulaiman Shabir Ahmad Syeda Sohaila Naz Sara Qaisar Sayyar Muhammad Amal Alotaibi Riaz Ullah 《Molecules (Basel, Switzerland)》2022,27(4)
Copper oxide nanoparticles (CuO NPs) were synthesized through the coprecipitation method and used as nanocarriers for etoricoxib (selective COX-2 inhibitor drug) and montelukast (leukotriene product inhibitor drug) in combination therapy. The CuO NPs, free drugs, and nanoformulations were investigated through UV/Vis spectroscopy, FTIR spectroscopy, XRD, SEM, and DLS. SEM imaging showed agglomerated nanorods of CuO NPs of about 87 nm size. The CE1, CE2, and CE6 nanoformulations were investigated through DLS, and their particle sizes were 271, 258, and 254 nm, respectively. The nanoformulations were evaluated through in vitro anti-inflammatory activity, in vivo anti-inflammatory activity, in vivo analgesic activity, in vivo anti-pyretic activity, and in vivo acute toxicity activity. In vivo activities were performed on albino mice. BSA denaturation was highly inhibited by CE1, CE2, and CE6 as compared to other nanoformulations in the in vitro anti-inflammatory activity. The in vivo bioactivities showed that low doses (5 mg/kg) of nanoformulations were more potent than high doses (10 and 20 mg/kg) of free drugs in the inhibition of pain, fever, and inflammation. Lastly, CE2 was more potent than that of other nanoformulations. 相似文献
144.
Munir Ullah Khan Liangbing Wang Zhao Liu Zehua Gao Shenpeng Wang Hongliang Li Wenbo Zhang Menglin Wang Prof. Zhengfei Wang Prof. Chao Ma Prof. Jie Zeng 《Angewandte Chemie (International ed. in English)》2016,55(33):9548-9552
As the electron transfer to CO2 is a critical step in the activation of CO2, it is of significant importance to engineer the electronic properties of CO2 hydrogenation catalysts to enhance their activity. Herein, we prepared Pt3Co nanocrystals with improved catalytic performance towards CO2 hydrogenation to methanol. Pt3Co octapods, Pt3Co nanocubes, Pt octapods, and Pt nanocubes were tested, and the Pt3Co octapods achieved the best catalytic activity. Both the presence of multiple sharp tips and charge transfer between Pt and Co enabled the accumulation of negative charges on the Pt atoms in the vertices of the Pt3Co octapods. Moreover, infrared reflection absorption spectroscopy confirmed that the high negative charge density at the Pt atoms in the vertices of the Pt3Co octapods promotes the activation of CO2 and accordingly enhances the catalytic activity. 相似文献
145.
Copper is found to be an effective catalyst for the preparation of alkynylphophonates. A novel copper-catalyzed one-pot synthesis of alkynylphophonates from terminal alkynes and dialkyl phosphites is developed which involves the haloalkynes intermediates. This method provides a unique and alternative approach to the well-documented oxidative coupling or arylpropiolic acid strategies. 相似文献
146.
147.
K. Naveed Ullah 《Il Nuovo Cimento D》1989,11(9):1349-1354
Summary This paper reports pressure broadening and shift coefficients of thallium 6P–9P
1/2,3/2 transitions by Ar and He as perturbers. Two-photon absorption Doppler free technique has been adopted. The perturing pressure
ranges from 300 Torr to 7 atm at 978 K. The red-shift due to Ar and the blue-shift due to He are found to vary linearly with
pressure. The Van der Waals constants for these transitions are also reported.
Riassunto Questo lavoro tratta dell’aumento di pressione e dei coefficienti di spostamento delle transizioni 6P–9P 1/2,3/2 con Ar e He come perturbatori. è stata adottata una tecnica libera Doppler di adsorbimento a due fotoni. La pressione che perturba varia da 300 Torr a 7 atm a 978 K. Si trova che lo spostamento verso il rosso dovuto ad Ar e lo spostamento verso il blu dovuto ad He variano liberamente con la pressione. Si presentano anche le costanti di Van der Waals per queste transizioni.
Резюме В этой статье исследуются коэффициенты уширения под действием давления и сдвига для переходов 6P–9P 1/2,3/2 в таллии, возмущенном Ar и He. Используется техника двух-фотонного поглощения. Рассматриваются давления от 300 торр до 7 атм при 978 К. Получено, что красный сдвиг, обусловленный Ar, и голубой сдвиг, обусловленный, He, изменяются линейно с давлением. Определяются постоянные Ван дер Ваальса для этих переходов.相似文献
148.
149.
Nazakat Ullah 《Pramana》1990,35(3):325-328
A nonrelativistic quark shell model (NRQSM) is used to derive an expression for the density of quarks in heavy spherical nuclei.
It is shown that quark density is related in a simple way with the probability of finding a nucleon in a nucleus. The quark
density is used to determine the ratio of average distance between two quarks to the average distance between two nucleons. 相似文献
150.
Nazakat Ullah 《Pramana》1973,1(5):209-211
The variable moment of inertia (VMI) model proposed by Holmberg and Lipas has been shown to be a special case of the VMI model
of Mariscottiet al. The solution of Mariscotti’s model is expressed in terms of hypergeometric functions, which directly give the rotational
energies or their expansions in terms of the quantityF(F+1), whereF is the total angular momentum. The present way of looking at the VMI model also tells us how to write the general dependence
of the vibrational energy and the moment of inertia on the energyE
J. 相似文献