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991.
This study demonstrates the presence of CH-π interaction in poly [9,9-dioctylfluorenyl-2,7-diyl] (PFO-1) due to an aggregate formation of PFO-1 in the liquid state. The absorption spectra of PFO-1 in certain solvents at low concentrations showed a single band at 390 nm. However, when using high concentrations, a new band at 437 nm appeared. This band is due to the aggregate formation of PFO-1. The aggregate formation occurs as a result of the CH interaction of the n-alkyl side chains with π-electrons in the benzene ring. The optical characteristics of another conjugated polymer of poly [9,9-di-(2-ethylhexyl)-fluorenyl-2,7-diyl] (PFO-2) were investigated to confirm the CH-π interaction. The absorption showed only one wavelength at 390 nm without any new band at the end of the spectrum, even at higher concentrations and lower temperatures. The main reason for the absence of aggregate formation in PFO-2 is the sterical hindrance caused by the branched alkyl side chains. In addition, Density Functional Theory (DFT) was used to compute the HOMO–LUMO transitions, electron charge distribution, and frontier molecular orbitals for each polymer. The Mulliken charge distribution and demonstrated a notable difference in the reactivity of the alkyl side chain, confirming the higher ability of PFO-1 to form CH-π bonds. docking model emphasized that the band at 437 nm could be attributed to the interaction between CH in the n-alkyl side chain and π bonds in the aromatic rings of PFO-1. 相似文献
992.
Farzad Kianersi Davood Amin Azarm Alireza Pour-Aboughadareh Peter Poczai 《Molecules (Basel, Switzerland)》2022,27(5)
The medicinal herb, lemon balm (Melissa officinalis L.), which is high in rosmarinic acid (RA), has well-known therapeutic value. The goals of this study were to investigate the effects of methyl jasmonate (MeJA) on RA content, total phenolic content (TPC), and total flavonoid content (TFC), as well as changes in expression of their biosynthesis-related key genes (MoPAL, Mo4CL, and MoRAS) in Iranian lemon balm ecotypes, as first reported. Our results revealed that MeJA doses significantly increase the RA content, TPC, and TFC in both ecotypes compared with the control samples. Additionally, the higher expression levels of MoPAL, Mo4CL, and MoRAS following treatment were linked to RA accumulation in all treatments for both Iranian lemon balm ecotypes. After 24 h of exposure to 150 µM MeJA concentration, HPLC analysis showed that MeJA significantly increased RA content in Esfahan and Ilam ecotypes, which was about 4.18- and 7.43-fold higher than untreated plants. Our findings suggested that MeJA has a considerable influence on RA, TPC, and TFC accumulation in MeJA-treated Iranian M. officinalis, which might be the result of gene activation from the phenylpropanoid pathway. As a result of our findings, we now have a better understanding of the molecular processes behind RA production in lemon balm plants. 相似文献
993.
Nur Amira Md Amin Siti Hamimah Sheikh Abdul Kadir Akmal Hisyam Arshad Norhaslinda Abdul Aziz Nurul Alimah Abdul Nasir Normala Ab Latip 《Molecules (Basel, Switzerland)》2022,27(6)
Vitamin E is known as an essential vitamin, and many studies had demonstrated the importance of vitamin E throughout the reproductive process, such as miscarriage, premature birth, preeclampsia, and intrauterine growth restriction, which could be caused by a lack of vitamin E during pregnancy. Its potent antioxidant properties can counteract the oxidative stress induced by oxygen free radicals and imbalance of oxidative-antioxidant levels, hence it may play a role in maintaining the normal function of the female reproductive system. Despite the fact that vitamin E is acknowledged as the substance needed for reproduction, its beneficial effects on female fertility, gynaecological health, and diseases are still poorly understood and lacking. Therefore, the goal of this paper is to provide a summary of the known roles of vitamin E supplementation in women for gynaecological health and reproductive-related diseases, as well as its future perspective. 相似文献
994.
995.
Teuku Azuar Rizal Muhammad Amin Syamsul Bahri Widodo Nazaruddin Abdul Rachman Fazri Amir Nurhalim Pane Teuku Meurah Indra Mahlia 《Entropy (Basel, Switzerland)》2022,24(1)
Indonesia has been blessed with excellent solar heat distribution, which can be used as renewable energy to heat water. Various technologies have been developed to utilize these inexhaustible thermodynamic resources, in the form of photons arrays, converted into concentrated heat for daily use, i.e., solar water heater. This renewable-based water heating system can provide significant energy efficiency, benefit the environment, and reduce energy use costs. This experimental study attempts to harvest the energy from the sun using a cylindrical through collector (CTC) type solar concentrator. The CTC was made of the solar reflective film (SRF) affixed to concentrator collector surfaces which was then mounted on an adjustable angle frame of the concentrator collector support. The heat generated from the concentrator was stored in water, and phase change material is embedded in the system to retain the heat longer. The research was carried out in Langsa City, Aceh, Indonesia. The results showed that water heaters using CTC systems could produce 16 L of hot water retained at 40–60 °C for four hours. With the addition of beeswax, the water temperature of the same capacity can be maintained at 40–60 °C for around 5 h. This technology demonstrated an excellent result that produces as much as 60 L of water per day, increasing solar thermal energy efficiency. This technology presented a great potential for replication or even for further development on an industrial scale. 相似文献
996.
Probing of ferrocenylanilines on model micelle/reverse micelle membrane and their enhanced reactivity for reactive oxidants 下载免费PDF全文
Ataf A. Altaf Amin Badshah Bhajan Lal Shahzad Murtaza Pabitra B. Chatterjee Kamran Akbar Debbie C. Crans 《应用有机金属化学》2018,32(6)
Reactive oxygen species are formed in the human body but can be removed by suitable antioxidants. In this study we synthesized and characterized three ferrocene derivatives, 4‐ferrocenylaniline (pFA), 3‐ferrocenylaniline (mFA) and 3‐methyl‐4‐ferrocenylaniline (MeFA), having significant potential to be used as antioxidants. The synthesized compounds are insoluble in water, with the solubility of these compounds increasing in micelle solution. The micelle and reverse micelle solutions were considered as model membranes. The synthesized compounds were probed on the model membranes, made by sodium dioctylsulfosuccinate reverse micelle and tetradecyltrimethylammonium bromide micelle, using 1H NMR spectroscopy. The 1H NMR results indicated that these compounds are present in the polar region of the model membrane interface. Quantitative measurements showed that mFA has the greatest ability to penetrate into the micelle membrane among these compounds, and pFA is least penetrating in this respect. Solubilization of these compounds in aqueous micelle solution facilitates crystallization (of mFA) and enhances the antioxidant potential of these compounds. X‐ray crystal structure analysis revealed that mFA captures water molecules during crystallization in micelle solution. Their ability to act as antioxidants was evaluated, in dimethylsulfoxide (DMSO) and in micelle solution, using standard 1,1‐ diphenyl‐2‐picrylhydrazyl (DPPH) assay. It was found that their antioxidant potential is good in DMSO and that potential increases on the interface of the model membrane. The highest increase (by 19.6%) in the antioxidant potential, on the model membrane interface, was observed for mFA. 相似文献
997.
In this study, a magnetically reusable artificial metalloenzyme has been constructed by co-immobilization of palladium nanoparticles as a strong oxidizing catalyst and laccase as an oxygen-activating enzyme into the cavities of magnetic mesocellular foams silica (Pd-Laccase@MMCF). The combination of Pd-Laccase@MMCF and hydroquinone (HQ) act as electron-transfer mediator system and make stepwise electron transfer from substrate to molecular oxygen. This catalyst system was used for the aerobic (i) oxidation of alcohols to the corresponding carbonyl compounds and (ii) dehydrogenation of 2-substituted-2,3-dihydroquinazolin-4(1H)-ones in phosphate buffer (0.1 M, pH 4.5, 4 mL)/THF (4%, 1 mL) as solvent under mild conditions. The co-immobilization of both laccase and Pd onto high surface area mesoporous support, high catalytic activity and magnetically separable and reusable make the present catalyst system superior to other currently available electron-transfer mediator systems. 相似文献
998.
Kalbasi Rasool Shahsavar Amin Afrand Masoud 《Journal of Thermal Analysis and Calorimetry》2020,139(4):2811-2820
Journal of Thermal Analysis and Calorimetry - In this study, a new design for energy recovery from the return air has been introduced to improve the air handling unit (AHU) performance through the... 相似文献
999.
Pan Bin Clarkson Christopher R. Atwa Marwa Tong Xia Debuhr Chris Ghanizadeh Amin Birss Viola I. 《Transport in Porous Media》2021,137(3):555-574
Transport in Porous Media - Nanoscale spontaneous imbibition is a common process in nanoporous soil and unconventional reservoirs. Due to the complexity of these natural nanoporous media, the... 相似文献
1000.
Mohamed Mahmoud Elseweidy Rawia sarhan Amin Hebatallah Husseini Atteia Reham Raafat El-Zeiky Naif A. Al-Gabri 《Applied biochemistry and biotechnology》2018,186(4):805-815
Platelet markers [soluble p selectin (sP-selectin) and soluble CD40 ligand (sCD40L)] are associated with platelet activation and cardiovascular risk. Both policosanol and 10-dehydrogingerdione are natural products with proven CETP inhibitory and antiatherogenic effects. Present work aimed mainly to investigate the levels of platelet activation biomarkers in the serum of dyslipidemic rabbits and the potential of these phytochemicals either alone or in a combination form to protect against atherogenicity. Additionally, this work clarified their effect on PCSK9, a key player in atherosclerosis progression. Daily administration of policosanol and/or 10-dehydrogingerdione at a dose level 10 mg/kg bw resulted in a CETP inhibitory activity, increasing HDL-C level. This protective effect was associated with improvement in lipid profile components and a reduction in PCSK9 level. Interestingly, this combination strengthened the CETP inhibitory activity of these phytochemicals, leading to a greater increase in serum HDL-C level than monotherapy. However, this combination did not enhance the reduction in PCSK9 level. Both drugs also decreased platelet activation and inflammation markers such as sCD40L, sP-selectin, and interferon-gamma (IFN-γ), and their combination showed a synergistic effect. Therefore, such phytochemicals may be regarded as promising agents in the protection against atherothrombosis risk. 相似文献