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51.
2H-1,4-Benzoxazines are major heterocyclic compounds with interesting biological and synthetic applications. Therefore, it would be very interesting to develop new efficient methods for their synthesis. Here, we synthesized 2H-1,4-benzoxazines in one pot using K2CO3/H2O in the ionic liquid of choice, [omim][BF4]. After reactions, products are extracted from [omim][BF4] by Et2O and the ionic liquid is recovered and successfully reused over several recycles. Results show that high yields of 3-aryl-2H-1,4-benzoxazine derivatives are obtained chemoselectively at room temperature from their corresponding o-aminophenols and phenacyl bromides. To our knowledge, our method represents the most efficient and straightforward route for the synthesis of 3-aryl-2H-1,4-benzoxazine derivatives in short times and under environmentally benign conditions.  相似文献   
52.
Environmental Science and Pollution Research - The significance of opportunistic infections in immunocompromised patients and the enigmatic pathogenicity of Blastocystis directed us to conduct the...  相似文献   
53.
Environmental Science and Pollution Research - Government control distorts energy prices which leads to loss of optimal factor combination and, as a result, affects efficiency. Previous researches...  相似文献   
54.
Food and Environmental Virology - Side by side air sampling was conducted using a PTFE filter membrane as dry sampler and an impinger containing a suitable culture medium as a wet sampler. Most of...  相似文献   
55.
With the increasing emphasis on the environment and the need to find environmentally friendly solvent systems, ionic liquids (IL)s have been emerging as promising green solvents to replace conventional solvents in recent years. They possess unique properties such as nonvolatility, low toxicity, ease of handling, nonflammability and high ionic conductivity; thus they have received much attention as green media for various chemistry processes. This report provides an extensive overview of use of ILs in polymers chemistry and technology.  相似文献   
56.
With the increasing emphasis on the environment and the need to find environmentally friendly solvent systems, ionic liquids (IL)s have been emerging as promising green solvents to replace conventional solvents in recent years. They possess unique properties such as nonvolatility, low toxicity, ease of handling, nonflammability and high ionic coductivity; thus they have received much attention as green media for various chemistry processes. This report provides an extensive overview of use of ILs in polymers chemistry and technology.  相似文献   
57.
This study explores the relationship between daylight exposure in urban residential units and the mood/happiness of nonworking female residents (housewives) in Isfahan, Iran. A growing body of evidence points to the physiological and psychological benefits of daylight, yet few studies have focused on the relationship between residential daylight and women's mental health. A cross‐sectional study was conducted using two‐stage random cluster sampling of nonworking female occupants of buildings in four residential districts. Mood/happiness was determined using the Oxford Happiness Inventory and the Fordyce Happiness Inventory. Spearman's rank correlation analysis was used to determine the relationship between the variables. A significant relationship was found between residents’ happiness and the amount of daylight in their residential units (Oxford Inventory, r = 0.68, P < 0.05; Fordyce Inventory, = 0.53, P < 0.05). The findings suggest that features of physical residential environments, such as daylight, may be linked to the happiness of housewives. Persons belonging to various demographic groups who spend the majority of their time indoors (e.g., housewives, children, elderly individuals, and people with disabilities) are most dependent on architecture and environmental design for their well‐being, and therefore, are most affected by design decisions.  相似文献   
58.
This research work consists on valorizing poultry waste by biotransformation into biofertilizers, associating this agro-industrial waste with algae (abundant natural resources) and molasses (a by-product of the sugar refining industry) ensuring a good contribution of nutritional chemical elements and obtaining a balanced formulation. A total of seven different formulations of the above three components, were examined in a simplex centroid design. A fungal inoculum of Aspergillus niger was used as a fermentation agent for better quality of biotransformation. The monitoring of this biotransformation is ensured during 15 days by following the evolution of physicochemical and microbiological parameters and, to understand the bioconversion of the simple compounds of the biofertilizer mixture such as short aliphatic chains, sugar, and amino acids into soluble mineral compounds, a Fourier transform infrared spectroscopy (FTIR) analysis was carried out before and after biotransformation. Finally, germination and fertilization tests were performed to evaluate the efficiency of the final product on a barley crop. The overall results of the present study showed that the mixture which contained 68.75% poultry waste, 12.5% molasses, and 18.75% algae presented the better microbiological and chemical safety criteria required for a good biofertilizer according to NF U44-551 standard.  相似文献   
59.
In this investigation, Fe3O4 magnetic nanoparticles (MNPs) were prepared by the alkalinization of an aqueous medium containing ferrous sulfate and ferric chloride. In the next step, a Fe3O4–AgCl magnetic nanocomposite was fabricated by the drop-by-drop addition of silver nitrate solution into a NaCl solution containing Fe3O4 MNPs. All prepared nanoparticles were characterized by transition electron microscopy (TEM), X-ray diffraction (XRD), and energy-dispersive X-ray spectroscopy (EDS). Both particle types varied in size from 2.5 to 20?nm, with an average size of 7.5?nm for Fe3O4 MNPs and 12.5?nm for Fe3O4–AgCl nanocomposites. The antibacterial effect of the Fe3O4 MNPs and fabricated Fe3O4–AgCl nanocomposites against Escherichia coli (ATCC 35218) were investigated by conventional serial agar dilution method using the Müller–Hinton Agar medium. The minimum inhibitory concentration was 4?mg?mL?1 for Fe3O4 MNPs and 2?mg?mL?1 for the Fe3O4–AgCl magnetic nanocomposites. Time-kill course assays showed that the Fe3O4–AgCl magnetic nanocomposites successfully killed all inoculated bacterial cells during an exposure time of 60?min. The antibacterial activity of recycled Fe3O4–AgCl magnetic nanocomposites over four 60?min cycles of antibacterial treatment was further tested against E. coli by the colony-forming unit (CFU) method. The antibacterial efficiency of the nanocomposites was constant over two cycles of antibacterial testing.  相似文献   
60.
Ovarian hormones affected some enzymes in reproductive tissues. Previous studies revealed Anethum graveolens (dill) seed extract elevated ovarian hormones. In this study, we compared the effects of dill seed and leaf extracts on some enzymes activities and infertility potential. Female Wistar rats were divided into three groups of control, dill seed and dill leaf aqueous extracts treated groups. Experimental groups received 1 mL of 0.5 g kg?1 of each extract orally for 25 days (five estrous cycles). Estradiol, progesterone, luteinizing hormone, and follicle stimulating hormone concentrations were determined. Uterus and ovaries were removed and their glucose-6-phosphate dehydrogenase, lactate dehydrogenase, and alkaline phosphatase activities were measured. Female rats of three groups were mated with untreated males. Fetuses were extracted in the 20th gestational day and their weights and crown rump lengths were measured. Anti-fertility and anti-implantation activities and fertility indices were calculated. Glucose-6-phosphate activity of dill seed treated group increased 1.6 times in the endometrium and 1.7 times in the myometrium. Progesterone concentration and lactate dehydrogenase activity of serum increased in the dill seed treated group compared to the control and dill leaf treated group. A significant decrease was observed in weights and crown rump lengths of fetuses, weights of placenta, and fertility index of the dill seed treated group compared to the control and dill leaf treated group, but its anti-implantation and anti-fertility indices increased. We suggested that high level of glucose-6-phosphate could entail increased oxidative stress in uterus and ovary. High lactate dehydrogenase activity in serum may affect cell membranes. Higher secretion of progesterone caused hormonal imbalance and produced estrous cycle irregularity. It was concluded that dill seed but not dill leaf extract could induce infertility in an animal model.  相似文献   
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