排序方式: 共有15条查询结果,搜索用时 31 毫秒
1.
In this study, total phenolics, flavonoids and vitamin C content vis-a-vis antioxidant activities were assayed in leaves and stem bark of Azadirachta indica, Butea monosperma, Cassia fistula, Mangifera indica, Syzygium cumini and Tamarindus indica using the 2,2-diphenyl-1-picrylhydrazyl (DPPH) and superoxide radical scavenging method. The DPPH radical scavenging activity positively correlated with the total phenolic content in both stem bark and leaf. Superoxide radical scavenging activity increased with increasing flavonoid contents. However, the vitamin C content could not be correlated with DPPH and superoxide radical scavenging capacity. 相似文献
2.
P. G. Shetty S. K. Sahu R. A. Takale M. Swarnkar N. Karunakara G. G. Pandit 《Journal of Radioanalytical and Nuclear Chemistry》2017,313(3):611-615
The outdoor and indoor environmental gamma dose rates in air have been measured in several parts of Udupi district, Karnataka, India using thermoluminescent dosimeters (TLDs). The outdoor annual gamma dose values varies in the range 0.49–1.17 mGy/year with mean 0.75 ± 0.18 mGy/year. Similarly indoor annual gamma dose varies in the range 0.51–1.10 mGy/year with mean 0.74 ± 0.13 mGy/year. The mean values of indoor and outdoor gamma dose rates were 84 and 86 nGy/h respectively with indoor to outdoor dose ratio of 1.02. 相似文献
3.
We report on a study of the proton induced hyperon production reactions. We discuss the theoretical efforts made towards understanding
the existing data and the uncertainties involved in the calculations. Our recent calculations of the missing mass spectra
for the pp → K
+ Λp reaction which involve a proper coupled channel treatment of the final state Λp interaction are presented. Significant differences in the results using different models of the hyperon-nucleon interaction
are found. 相似文献
4.
5.
In this work, epichlorohydrin (Ech) crosslinked cellulose hydrogels have been prepared and loaded with urea (Ur) for controlled release as a fertilizer. A detailed study of swelling behavior of these hydrogels and their urea releasing capacity has been carried out under various experimental conditions. The dynamic swelling and release data has been applied on various kinetic models. Finally, using a novel Sprinkler Based Irrigation (SBI) model, a model plant has been irrigated with water in the presence of urea-loaded hydrogel. It was found that plants, irrigated in the presence of urea-loaded hydrogel exhibited a better growth as compared to the control plant sample. 相似文献
6.
Abhishek Swarnkar Ramya Chulliyil Vikash Kumar Ravi Dr. Mir Irfanullah Dr. Arindam Chowdhury Dr. Angshuman Nag 《Angewandte Chemie (International ed. in English)》2015,54(51):15424-15428
Traditional CdSe‐based colloidal quantum dots (cQDs) have interesting photoluminescence (PL) properties. Herein we highlight the advantages in both ensemble and single‐nanocrystal PL of colloidal CsPbBr3 nanocrystals (NCs) over the traditional cQDs. An ensemble of colloidal CsPbBr3 NCs (11 nm) exhibits ca. 90 % PL quantum yield with narrow (FWHM=86 meV) spectral width. Interestingly, the spectral width of a single‐NC and an ensemble are almost identical, ruling out the problem of size‐distribution in PL broadening. Eliminating this problem leads to a negligible influence of self‐absorption and Förster resonance energy transfer, along with batch‐to‐batch reproducibility of NCs exhibiting PL peaks within ±1 nm. Also, PL peak positions do not alter with measurement temperature in the range of 25 to 100 °C. Importantly, CsPbBr3 NCs exhibit suppressed PL blinking with ca. 90 % of the individual NCs remain mostly emissive (on‐time >85 %), without much influence of excitation power. 相似文献
7.
We have investigated the fast ethylamine gas sensing of 2-chloro-3,5-dinitrobenzotrifluoride(CDBF) loaded poly(acrylonitrile) nanofiber based on an intermolecular charge-transfer complexation.Reversible response and recovery were achieved using alternating gas exposure.This system shows a fast ethylamine gas sensing within 0.4 s. 相似文献
8.
BK Srivastava 《Pramana》2001,57(2-3):301-313
A systematic analysis of the multifragmentation (MF) in fully reconstructed events from 1A GeV Au, La and Kr collisions with C has been performed. Detailed comparisons of the various fragment properties are presented
as a function of excitation energy, E*th. The charged particle multiplicity from MF stage shows a saturation beyond E*th ∼ 8 MeV/nucleon for Kr. The universal behavior of intermediate mass fragment yields and of the size of the largest fragment
is observed only for Au and La when scaled with size of the system. The Kr data are found to lack this property. Moments of
the fragment size distribution show that the Kr MF is different than the MF of Au and La. A power law behavior is observed
for Au and La with exponent τ>2, while for Kr τ<2. The results are compared with the statistical multifragmentation model (SMM). A single value of all the parameters of
the model fits the data for all the three systems. The breakup of Au and La is consistent with a continuous phase transition.
The data indicate that both E*th and the isotope ratio temperature T
Hc-DT
decrease with increase in system size at the critical point. The breakup temperature obtained from SMM also shows the same
trend as seen in data. This trend is attributed primarily to the increasing Coulomb energy with finite size effects playing
a smaller role. The percolation and Ising model studies for finite size neutral matter show behavior which is opposite to
the one seen in the present work.
EOS Collaboration 相似文献
9.
We report a simple soft chemical method for the synthesis of ZnS nanoparticles using varying concentration of cationic surfactant CTAB and examine its surface properties. Powder X-ray diffraction, UV-vis spectroscopy, photoluminescence spectroscopy, selective area electron diffraction, and transmission electron microscopy are used to characterize the as prepared ZnS nanoparticles. XRD and TEM measurements show the size of polydispersed ZnS nanoparticles is in the range of 2-5 nm with cubic phase structure. The photoluminescence spectrum of ZnS nanoparticles exhibits four fluorescence emission peaks centered at 387 nm, 412 nm, 489 nm and 528 nm showing the application potential for the optical devices. In Raman spectra of ZnS nanoparticles, the modes around 320, 615 and 700 cm−1 are observed. 相似文献
10.
R. A. Takale S. K. Sahu M. Swarnkar P. G. Shetty G. G. Pandit 《Journal of Radioanalytical and Nuclear Chemistry》2014,302(3):1405-1411
This study discusses the optimization of CaSO4: Dy phosphor for its use in environmental monitoring program. In India environmental gamma radiation monitoring, using TLDs is being carried out since last four decades on regular basis. Investigations are made to determine optimum thickness of teflon disc and doping concentration. Teflon disc 0.8 mm thick was found optimum with the 0.2 mol% Dy concentration for highest sensitivity for environmental gamma radiation monitoring. 相似文献