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31.
Lalremsiami Hrahsel Adreeja Basu Lingaraj Sahoo Robert Thangjam 《Applied biochemistry and biotechnology》2014,172(3):1530-1539
An efficient in vitro propagation method has been developed for the first time for Musa acuminata (AAA) cv. Vaibalhla, an economically important banana cultivar of Mizoram, India. Immature male flowers were used as explants. Murashige and Skoog’s (MS) medium supplemented with plant growth regulators (PGRs) were used for the regeneration process. Out of different PGR combinations, MS medium supplemented with 2 mg L?1 6-benzylaminopurine (BAP) + 0.5 mg L?1 α-naphthalene acetic acid (NAA) was optimal for production of white bud-like structures (WBLS). On this medium, explants produced the highest number of buds per explant (4.30). The highest percentage (77.77) and number (3.51) of shoot formation from each explants was observed in MS medium supplemented with 2 mg L?1 kinetin + 0.5 mg L?1 NAA. While MS medium supplemented with a combination of 2 mg L?1 BAP + 0.5 mg L?1 NAA showed the maximum shoot length (14.44 cm). Rooting efficiency of the shoots was highest in the MS basal medium without any PGRs. The plantlets were hardened successfully in the greenhouse with 96 % survival rate. Random amplified polymorphic DNA (RAPD) and inter-simple sequence repeat (ISSR) markers were employed to assess the genetic stability of in vitro regenerated plantlets of M. acuminata (AAA) cv. Vaibalhla. Eight RAPD and 8 ISSR primers were successfully used for the analysis from the 40 RAPD and 30 ISSR primers screened initially. The amplified products were monomorphic across all the regenerated plants and were similar to the mother plant. The present standardised protocol will find application in mass production, conservation and genetic transformation studies of this commercially important banana. 相似文献
32.
Inoue Kazumasa Sahoo Sarata Kumar Veerasamy Nimelan Kasahara Shogo Fukushi Masahiro 《Journal of Radioanalytical and Nuclear Chemistry》2020,324(3):1423-1434
Journal of Radioanalytical and Nuclear Chemistry - Absorbed dose rates in air for 20 residential areas in Odisha were measured using a vehicle-mounted NaI(Tl) scintillation spectrometer. The... 相似文献
33.
One of the long standing problems in quantum chemistry had been the inability to exploit full spatial and spin symmetry of an electronic Hamiltonian belonging to a non‐Abelian point group. Here, we present a general technique which can utilize all the symmetries of an electronic (magnetic) Hamiltonian to obtain its full eigenvalue spectrum. This is a hybrid method based on Valence Bond basis and the basis of constant z‐component of the total spin. This technique is applicable to systems with any point group symmetry and is easy to implement on a computer. We illustrate the power of the method by applying it to a model icosahedral half‐filled electronic system. This model spans a huge Hilbert space (dimension 1,778,966) and in the largest non‐Abelian point group. The C60 molecule has this symmetry and hence our calculation throw light on the higher energy excited states of the bucky ball. This method can also be utilized to study finite temperature properties of strongly correlated systems within an exact diagonalization approach. © 2011 Wiley Periodicals, Inc. Int J Quantum Chem, 2012 相似文献
34.
35.
An innovative conductometric measurement technique using a nonconventional but high‐performance (high‐precision, high‐resolution, rapid response features for online graphic display) in house–built pulsating conductivity monitoring instrument has been deployed to study the kinetic behavior during the reaction of ethyl acetate and NaOH. A laboratory‐made constant temperature reaction bath with the facility of continuous stirring of solution for homogeneous mixing was used to carry out experiments at desired solution temperatures. Rate constants of the saponification reaction in the temperature range at various temperatures (30–55°C) were determined, and the results were compared with the reported values. Although the reported data exhibit wide scatter, our data are in agreement with some of the literature data. From these data, thermodynamic parameters such as activation energy, activation enthalpy, activation entropy, and activation free energy have been evaluated. With the introduction of this novel conductometric measurement technique, the determination of rate constants at various solution temperatures becomes much simpler and faster. © 2011 Wiley Periodicals, Inc. Int J Chem Kinet 43: 648–656, 2011 相似文献
36.
Ch.?Binek P.?Borisov Xi?Chen A.?Hochstrat S.?Sahoo W.?KleemannEmail author 《The European Physical Journal B - Condensed Matter and Complex Systems》2005,45(2):197-201
Perpendicular exchange bias (PEB) involving perpendicular
magnetic anisotropy (PMA) in both the antiferromagnetic (AF) pinning and the
ferromagnetic (FM) sensor layer is expected to become important in future
perpendicular recording and sensing devices. Further, because of the reduced
spin dimensionality, PEB promises to be easier understandable than the
conventional planar exchange bias (EB). In addition to its first realization
using the Ising-type AF compounds FeF2 and FeCl2 we have tested
control strategies of EB being alternative to the conventional magnetic and
thermal ones. Indeed, specific symmetry properties of the pinning layer have
been shown to enable mechanical (viz. piezomagnetic via FeF2) and electric
control (viz. magneto-electric via Cr2O3) of EB, respectively.
Electric control promises to become relevant for TMR devices in MRAM
technology. 相似文献
37.
C.?SurEmail author B. K.?Sahoo R. K.?Chaudhuri B. P.?Das D.?Mukherjee 《The European Physical Journal D - Atomic, Molecular, Optical and Plasma Physics》2005,32(1):25-31
We have employed the relativistic coupled cluster theory to calculate
the magnetic dipole and electric quadrupole hyperfine constants for
the ground and low lying excited states of singly ionized magnesium.
Comparison with experimental and the other theoretical results are
done and predictions are also made for a few low lying excited states
which could be of interest. We have made comparative studies of the
important many body effects contributing to the hyperfine constants
for the different states of the ion. 相似文献
38.
Poly(butyl acrylate) (PBA)/sodium silicate (SS) nanocomposites were prepared via emulsifier-free emulsion technique in presence of Cu(II)/glycine chelate complex and ammonium persulfate (APS) initiator. The strongly hydrophobic PBA was intercalated into the hydrophilic SS layer. Since the interlayers of silicate were filled with sodium cations, the hydrophilic properties were enhanced and lead to high degree of swelling. The formation of the PBA/SS nanocomposite was confirmed by infrared spectra (IR). Furthermore, as evidenced by transmission electron microscopy (TEM), the composite so obtained was found to have nanoscale structure. X-ray diffraction (XRD) was used to characterize the nanoscale dispersion of the layer silicate and useful for measurement of d-spacing in interlayer system. It was found from thermogravimetric analysis that PBA/SS nanocomposites had more thermal stability as compared to raw PBA due to intercalation. Burning test of the nanocomposites performance exhibited a flame retardant property, which was also verified from cone calorimeter analysis. For its commercialization, the ecological friendly nature was studied via biodegradation and was found to have better biodegradability than the raw PBA. 相似文献
39.
B. K. Rana R. M. Tripathi S. K. Sahoo N. K. Sethy V. S. Sribastav A. K. Shukla V. D. Puranik 《Journal of Radioanalytical and Nuclear Chemistry》2010,285(3):711-717
A brief study on dissolved radionuclides in aquatic environment, especially in ground water, constitutes the key aspect for assessment and control of natural exposure. In the present study the distribution of natural uranium and 226Ra concentration were measured in ground water samples collected within a 10 km radius around the Narwapahar uranium mine in the Singhbhum thrust belt of Jharkhand, India in 2007–2008. The natural uranium content in the ground water samples in this region was found to vary from 0.1 to 3.75 μg L?1 with an average of 0.87 ± 0.73 μg L?1 and 226Ra concentration was found to vary from 5.2 to 38.1 mBq L?1 with an average of 13.73 ± 7.34 mBq L?1. The mean annual ingestion dose due to intake of natural uranium and 226Ra through drinking water pathway to male and female adults population was estimated to be 6.55 and 4.78 μSv y?1, respectively, which constitutes merely a small fraction of the reference dose level of 100 μSv y?1 as recommended by WHO. 相似文献
40.
Spatially homogeneous Bianchi types V and VI0 cosmological models are studied with source cosmic cloud strings coupled with electromagnetic field in Rosen’s (Gen. Relativ.
Gravit. 4:435, 1973) bimetric theory of relativity. It is observed that Bianchi type V space time is feasible whereas Bianchi type VI0 is not feasible. In the feasible case different equations of state for cosmic strings with Maxwell fields do not survive
in this theory and the space-time turns out to be flat. 相似文献