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81.
Russian Journal of Organic Chemistry - A new series of 4-(1H-imidazol-4-yl)-2-(substituted phenyl)-1,4-dihydrobenzo[4,5]imidazo[1,2-a]­pyrimidines have been synthesized via a one-pot reaction...  相似文献   
82.
Over the last two decades, oxide nanostructures have been continuously evaluated and used in many technological applications. The advancement of the controlled synthesis approach to design desired morphology is a fundamental key to the discipline of material science and nanotechnology. These nanostructures can be prepared via different physical and chemical methods; however, a green and ecofriendly synthesis approach is a promising way to produce these nanostructures with desired properties with less risk of hazardous chemicals. In this regard, ZnO and TiO2 nanostructures are prominent candidates for various applications. Moreover, they are more efficient, non-toxic, and cost-effective. This review mainly focuses on the recent state-of-the-art advancements in the green synthesis approach for ZnO and TiO2 nanostructures and their applications. The first section summarizes the green synthesis approach to synthesize ZnO and TiO2 nanostructures via different routes such as solvothermal, hydrothermal, co-precipitation, and sol-gel using biological systems that are based on the principles of green chemistry. The second section demonstrates the application of ZnO and TiO2 nanostructures. The review also discusses the problems and future perspectives of green synthesis methods and the related issues posed and overlooked by the scientific community on the green approach to nanostructure oxides.  相似文献   
83.
Putrajeevak (Putranjiva roxburghii Wall.; synonym Drypetes roxburghii (Wall.) Hurus) seeds have been used since ancient times in the treatment of infertility in the Ayurvedic system of medicine in India. In this study, the oil component of Putrajeevak seeds (PJSO) was extracted using the supercritical fluid extraction (SCFE) method using liquid CO2 and the constituents were analyzed using gas chromatography-flame ionized detectorand high-performance thin-layer chromatography. PJSO contained trace amounts of β-sitosterol with oleic and linoleic acids as the major fatty acid constituents. Male and female zebrafish were mutagenized with N-ethyl-N-nitrosourea (ENU) and fish that produced less than 20 viable embryos were selected for the study. SCFE oil extracts from the P. roxburghii seeds were used in this study to reverse fertility impairment. The mutant fish were fed with PJSO for a period of 14 days and the rates of fertility, conception, and fecundity were determined with wild-type healthy fish as a breeding partner. Treatment with PJSO increased the ovarian follicle count as well as the number of mature eggs, while reducing the number of ovarian cysts. Sperm count as well as sperm motility were greatly enhanced in the ENU-mutagenized male zebrafish when treated with PJSO. The results obtained in this study demonstrate the effectiveness of P. roxburghii seed oil in reversing impaired fertility in both male and female zebrafish models.  相似文献   
84.
The electron hosing instability in the blow-out regime of plasma-wakefield acceleration is investigated using a linear perturbation theory about the electron blow-out trajectory in Lu et al. [in Phys. Rev. Lett. 96, 165002 (2006)10.1103/PhysRevLett.96.165002]. The growth of the instability is found to be affected by the beam parameters unlike in the standard theory Whittum et al. [Phys. Rev. Lett. 67, 991 (1991)10.1103/PhysRevLett.67.991] which is strictly valid for preformed channels. Particle-in-cell simulations agree with this new theory, which predicts less hosing growth than found by the hosing theory of Whittum et al.  相似文献   
85.
The onset of trapping of electrons born inside a highly relativistic, 3D beam-driven plasma wake is investigated. Trapping occurs in the transition regions of a Li plasma confined by He gas. Li plasma electrons support the wake, and higher ionization potential He atoms are ionized as the beam is focused by Li ions and can be trapped. As the wake amplitude is increased, the onset of trapping is observed. Some electrons gain up to 7.6 GeV in a 30.5 cm plasma. The experimentally inferred trapping threshold is at a wake amplitude of 36 GV/m, in good agreement with an analytical model and PIC simulations.  相似文献   
86.
Research on Chemical Intermediates - We have developed a simple synthetic protocol for the preparation of novel 3-(3-(4-fluorophenyl)-1-phenyl-1H-pyrazol-4-yl)-5-arylisoxazoles. The structure of...  相似文献   
87.
JPC – Journal of Planar Chromatography – Modern TLC - Marmelosin is one of the major phytochemical constituents of Aegle marmelos (L.) Corr. (Rutaceae). Till date, there are no methods...  相似文献   
88.
A simple, efficient, and environmentally benign method for the synthesis of 4H-chromene derivatives was developed using well ordered and recoverable amino functionalized silica gel as a base catalyst. The 4H-chromene derivatives were obtained in short time and excellent yield(87%–96%) by three component reaction of aldehydes, malononitrile and cyclic 1,3-diketones in water at 70 8C.  相似文献   
89.
The platinum(II) complexes with N,S-donor ligand have been synthesised and characterised by physiological techniques like elemental, electronic, Fourier transform infrared, hydrogen-1 nuclear magnetic resonance (1H NMR) and liquid chromatography–mass spectrometry spectra. The synthesised complexes have been checked for their DNA binding ability by absorption titration and viscosity measurement, and the results show that the complexes binds to herring sperm DNA (HS DNA) via covalent mode of binding. The DNA cleavage activity of synthesised complexes has been carried out by gel electrophoresis experiment using supercoiled form of pUC19 DNA, showing the unwinding of the negatively charged supercoiled DNA. Brine shrimp (Artemia cysts) lethality bioassay technique has been applied for the determination of toxic property of synthesised complexes in terms of micromolars.  相似文献   
90.
Journal of Radioanalytical and Nuclear Chemistry - In the present study, the dissolution kinetics of UO2 pellets in nitric acid has been investigated. Kinetic rate expressions based on...  相似文献   
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