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171.
Extending the minimal supersymmetric standard model to explain small neutrino masses via the inverse seesaw mechanism can lead to a new light supersymmetric scalar partner which can play the role of inelastic dark matter (IDM). It is a linear combination of the superpartners of the neutral fermions in the theory (the light left-handed neutrino and two heavy standard model singlet neutrinos) which can be very light with mass in ~5-20 GeV range, as suggested by some current direct detection experiments. The IDM in this class of models has keV-scale mass splitting, which is intimately connected to the small Majorana masses of neutrinos. We predict the differential scattering rate and annual modulation of the IDM signal which can be testable at future germanium- and xenon-based detectors. 相似文献
172.
Yijun Yang Alparslan Oztekin Sudhakar Neti Satish Mohapatra 《Journal of nanoparticle research》2012,14(5):852
The present study demonstrates the importance of actual agglomerated particle size in the nanofluid and its effect on the
fluid properties. The current work deals with 5 to 100 nm nanoparticles dispersed in fluids that resulted in 200 to 800 nm
agglomerates. Particle size distributions for a range of nanofluids are measured by dynamic light scattering (DLS). Wet scanning
electron microscopy method is used to visualize agglomerated particles in the dispersed state and to confirm particle size
measurements by DLS. Our results show that a combination of base fluid chemistry and nanoparticle type is very important to
create stable nanofluids. Several nanofluids resulted in stable state without any stabilizers, but in the long term had agglomerations
of 250 % over a 2 month period. The effects of agglomeration on the thermal and rheological properties are presented for several
types of nanoparticle and base fluid chemistries. Despite using nanodiamond particles with high thermal conductivity and a
very sensitive laser flash thermal conductivity measurement technique, no anomalous increases of thermal conductivity was
measured. The thermal conductivity increases of nanofluid with the particle concentration are as those predicted by Maxwell
and Bruggeman models. The level of agglomeration of nanoparticles hardly influenced the thermal conductivity of the nanofluid.
The viscosity of nanofluids increased strongly as the concentration of particle is increased; it displays shear thinning and
is a strong function of the level of agglomeration. The viscosity increase is significantly above of that predicted by the
Einstein model even for very small concentration of nanoparticles. 相似文献
173.
A. Sargsyan M. G. Bason D. Sarkisyan A. K. Mohapatra C. S. Adams 《Optics and Spectroscopy》2010,109(4):529-537
Experimental results of the study of processes of electromagnetically induced transparency (EIT) and two-photon absorption
(TPA) are presented for the ladder Ξ-system obtained using the 5S-5P-nD, mS system of levels of the 85Rb and 87Rb atoms with n = 5, 26, and 27 and m = 39 and 48. To perform these studies, a high-temperature optical cell was designed with several regions with the following
thicknesses L: 2 mm, 0.7 mm, and the region of 2–6 μm. The advantages of using thin cells over ordinary cells several centimeters thick
are demonstrated. It is shown that the EIT resonance parameters for n = 5, 26, and 27 deteriorate insignificantly for thickness down to 700 μm. The TPA is recorded with the cell thickness decreasing
down to L = 6 μm. It is shown that using the EIT and TPA processes makes it possible to measure the hyperfine and fine structures of
highlying atomic levels. The influence of the cell walls is appreciable in recording the EIT resonances in the system 5S-5P-39S with L = 0.7 mm and in the system 5S-5P-48S with L = 2 mm. Possible applications of the processes studied are indicated. 相似文献
174.
Mohapatra D Nakao M Nishida S Abe K Abe K Adachi I Aihara H Anipko D Arinstein K Asano Y Aulchenko V Aushev T Bahinipati S Bakich AM Balagura V Barbero M Bedny I Bitenc U Bizjak I Blyth S Bondar A Bozek A Bracko M Browder TE Chao Y Chen A Chen KF Chen WT Cheon BG Chistov R Choi Y Chuvikov A Cole S Dalseno J Danilov M Dash M Dragic J Drutskoy A Eidelman S Epifanov D Fratina S Gabyshev N Gershon T Gokhroo G Golob B Gorisek A Ha HC Haba J Hara T Hastings NC Hayasaka K Hayashii H Hazumi M Hinz L 《Physical review letters》2006,96(22):221601
We report the observation of the flavor-changing neutral current process b-->dgamma using a sample of 386 x 106 B meson pairs accumulated by the Belle detector at the KEKB e+e- collider. We measure branching fractions for the exclusive modes B--->rho-gamma, B0rho0gamma, and B0omegagamma. Assuming that these three modes are related by isospin, we find B(B-->(rho,gamma)gamma)=[Formula: See Text] with a significance of 5.1sigma. This result is used to determine the ratio of Cabibbo-Kobayashi-Maskawa matrix elements /Vtd/Vts/ to be [Formula: See Text]. 相似文献
175.
Mamata Mohapatra K. Rout S. K. Gupta P. Singh S. Anand B. K. Mishra 《Journal of nanoparticle research》2010,12(2):681-686
The present article describes a novel synthesis route for nano-sized goethite (α-FeOOH) using hydrazine sulphate as an additive.
The X-ray diffraction (XRD) peaks of synthesized powder matched well with those of α-FeOOH. Transmission electron microscopy
(TEM) showed the particles of irregular shape in the range of 1–10 nm. Batch adsorption experiments for fluoride uptake were
performed to study the influence of various experimental parameters such as contact time (10 min to 7 h), initial fluoride
concentration (10–150 mg L−1), pH (2–11.6) and the presence of competing anions. The time data fitted well to pseudo-second-order kinetic model. The fluoride
removal passed through broad maxima in pH ranges of 6–8. High adsorption capacity of 59 mg g−1 goethite was obtained. The isothermic data fitted well to Freundlich model. The presence of other ions namely chloride and
sulphate adversely affected fluoride removal. Fluoride from contaminated water sample could be successfully brought down from
10.25 to 0.5 mg L−1. 相似文献
176.
Mitali Mishra Seetaram Mohapatra Nilima Priyadarsini Mishra Bighnanshu K. Jena Pravati Panda Sabita Nayak 《Tetrahedron letters》2019,60(33):150925
Heterocyclic compounds particularly five, six and seven membered ring containing heterocycles are the most abundant which constitute a staggeringly diverse and important class of molecules that occur ubiquitously in a variety of synthetic drugs, bioactive natural products, pharmaceuticals and agrochemicals. Owing to the glorious past and impressive present of the biologically active heterocyclic scaffolds, these skeletons have long been a subject of immense interest. Hence, substantial efforts have been made to the development of new and innovative synthetic strategies for the synthesis of these heterocycles involving use of different metal catalysts, organic and inorganic reagents etc. Among the different types of metal catalysts used, iron catalysts are one of the cheap and easily available. In recent time, several new and innovative iron(III) chloride catalyzed synthesis of heterocycles with structural diversity are coming in the forefront of the literature by the scientific community. This review highlights the advancements made so far by iron(III) chloride for the synthesis of different assemblies of small heterocycles covering the year 2014–2018. 相似文献
177.
N. Mohapatra K. K. Iyer E. V. Sampathkumaran 《The European Physical Journal B - Condensed Matter and Complex Systems》2008,63(4):451-454
We report a large entropy change (ΔS) below 300 K, peaking near T
C
= 220 K, due to isothermal change of magnetic field, for Gd4Co3, with a refrigeration capacity higher than that for, say, LaFe11.4Si1.6, ordering magnetically in the same temperature range. A noteworthy finding is that the isothermal magnetization is nonhysteretic
— an important criterion for magnetic refrigeration without loss. ΔS behavior is also compared with that of magnetoresistance. 相似文献
178.
A sodium ion conducting composite polymer electrolyte (CPE) prepared by solution-caste technique by dispersion of an electrochemically
inert ceramic filler (SnO2) in the PEO–salt complex matrix is reported. The effect of filler concentration on morphological, electrical, electrochemical,
and mechanical stability of the CPE films has been investigated and analyzed. Composite nature of the films has been confirmed
from X-ray diffraction and scanning electron microscopy patterns. Room temperature d.c. conductivity observed as a function
of filler concentration indicates an enhancement (maximum) at 1–2 wt% filler concentration followed by another maximum at
∼10 wt% SnO2. This two-maxima feature of electrical conductivity as a function of filler concentration remains unaltered in the CPE films
even at 100 °C (i.e., after crystalline melting), suggesting an active role of the filler particles in governing electrical
transport. Substantial enhancement in the voltage stability and mechanical properties of the CPE films has been noticed on
filler dispersion. The composite polymer films have been observed to be predominantly ionic in nature with t
ion ∼ 0.99 for 1–2 wt% SnO2. However, this value gets lowered on increasing addition of SnO2 with t
ion ∼ 0.90 for 25 wt% SnO2. A calculation of ionic and electronic conductivity for 25 wt% of SnO2 film works out to be ∼2.34 × 10−6 and 2.6 × 10−7 S/cm, respectively. 相似文献
179.
Discovery of neutrino mass has put the spotlight on the supersymmetric (SUSY) SO(10) model as a natural candidate for grand unification of forces and matter. However, the suppression of proton decay is a major problem in such SUSY grand unified models. In this Letter we show how to alleviate this problem by simple threshold effects which raise the colored Higgsino masses and the grand unification scale to greater than or similar to 10(17) GeV. There exist only four types of fields arising from different SO(10) representations which can generate this kind of threshold effect. Some of these fields also generate a sizable flavor violation in the quark sector compared to the lepton sector. The b-tau unification can work in these types of models even for intermediate values of tanbeta. 相似文献
180.
JPC – Journal of Planar Chromatography – Modern TLC - In view of high pharmacological significance and urgent need to identify high-yielding plant sources of betulin (1) and betulinic... 相似文献