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61.
This work presents the investigation of some commercially available and commonly used Si3N4 foils prepared with LPCVD technique. The density and the stoichiometry of these films were determined by Rutherford backscattering spectroscopy and profilometry, while the study of impurities was achieved with particle induced X-ray emission method. It was found that the density of the studied Si3N4 films is significantly less (~2.71 g cm?3), while the stoichiometry is close to the values of the bulk material. The results were verified by measuring the ion energy loss through the films by scanning transmission ion microscopy.  相似文献   
62.
63.
An efficient method was developed for the synthesis of highly substituted naphthalenes through rhodium‐catalyzed oxidative benzannulation of N‐pivaloylanilines with internal alkynes. The benzannulation reaction proceeded smoothly through dual C?H bond activation to produce the corresponding highly substituted naphthalene products in satisfactory to good yields.  相似文献   
64.
Synthetic dyes are released into the environment from textile industrial effluents. The discharge of this colored wastewater into rivers and lakes leads to a reduction in sunlight penetration in natural water bodies, which, in turn, decreases both photosynthetic activity and dissolved oxygen concentration and is toxic to living beings. Bacterial isolates are optimized for growth and biomass production before using them for decolorizing dye effluent. The bacterial isolates Bacillus sp. 1 and Bacillus sp. 2 were employed at different percentages by volume with standard nutrient concentration. Of these bacterial isolates Bacillus sp. 2 recorded maximum color reduction. The pH and electrical conductivity (EC) were reduced in the decolorized effluent, and a reduction in biologic oxygen demand, chemical oxygen demand, total suspended solids, and total dissolved solids (TDS) were also observed.  相似文献   
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66.
Synthesis of a new scaffold derived from iminodipropionic acid for the preparation of peptide dimers and tetramers is described.  相似文献   
67.
Two polymorphs of zero-dimensional zinc phosphate with the formula, 0[Zn(2,2′-bipy)(H2PO4)2], have been synthesized employing hydrothermal technique and their structure determined by single crystal X-ray diffraction. Both the structures consists of ZnO3N2 distorted trigonal-bipyramidal and PO2(OH)2 tetrahedral units linked through their vertices giving rise to a zero-dimensional molecular zinc phosphate. The structures are stabilized by extensive hydrogen bond interactions between zero-dimensional monomers. The structures display subtle differences in their packing created by hydrogen bond interactions. Crystal data: polymorph I, triclinic, space group (No. 2), , , , α=67.32(3)°, β=81.67(3)°, γ=69.29(3)°, , Z=2; polymorph II, triclinic, space group (No. 2), , , , α=97.37(2)°, β=100.54(2)°, γ=100.98(2)°, , Z=2.  相似文献   
68.
To understand the low-lying singlet states of dithienyl polyenes, we investigated the solvatochromism of a series of α,ω-di(2-dithienyl 3,4-butyl) polyenes having n=1–5 double bonds. Absorption and emission spectra were collected in a series of aprotic solvents. The absorption energy dispersion effect sensitivity increased smoothly with n, reaching asymptotic behavior as n approached 5. The emission energy had less solvent sensitivity. The trends gave evidence for the existence of a 1B*u absorbing state and a 1A*g emitting state. We observed sensitivity of the absorbing and emitting states to solute–solvent electrostatic interactions, suggesting the dithienyl polyenes had a polar ground state conformation.  相似文献   
69.
Green synthesis of nanoparticles by eco-friendly methods is a recent technique which draws the attention of researchers because of the reward over many conventional chemical methods. The present work focuses on aqueous Limonia acidissima leaf extract in synthesizing silver nanoparticles and its applications in a simple way. The silver nanoparticles formed were characterized by Infrared, Ultra violet-visible, X-ray diffraction, transmission electron microscopic, and atomic force microscopic techniques. The powder X-ray diffraction studies and transmission electron microscopic images reveal that the silver nanoparticles synthesized were approximately 10–40 nm and have a spherical structure. The nanoparticles were assayed for their antibacterial, antifungal and antioxidant activity. The antimicrobial studies for the silver nanoparticles show a maximum zone of inhibition of 8.8 mm for Bacillus subtilis bacteria and 8.5 mm for Candida albicans fungi at 3 and 1 μg/mL respectively. In-silico ADMET studies reveal that the toxicity, bioactivity, pharmacokinetics and drug-likeness properties of Limonia acidissima leaf extract is good. The molecular docking studies show that the microbial activity is high for Bacillus subtilis and Candida albicans showing the coincidence of the in silico and in vitro studies as expected. The free radical scavenging activity of nanoparticles is 80 for 100 μg/mL. The 50% of inhibition of silver nanoparticles against human breast cancer cell lines is 18 μg/mL. It is evident that silver nanoparticles would be helpful in treating cancer cell lines and have great perspectives in the biomedical sector.  相似文献   
70.
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