Structure, stability and dissociation of silanitriles RSiN (R = H2B, H2N, H2P)

Structure, stability, and dissociation of H₂BSiN, H₂NSiN, H₂PSiN and their isomers H₂BNSi, H₂NNSi, H₂PNSi have been studied in detail using ab initio MP2 and CCSD(T) methods. After dissociation of H₂BNSi, H₂NNSi, H₂PNSi and their isomers, the fragmented atoms have been considered to be either in their ground state or in their valence excited state in various dissociation channels. Only allowed dissociations of these molecules are considered. Various dissociation channels of H₂BNSi, H₂NNSi, H₂PNSi and their isomers have been explored and interesting trends are observed for the dissociation of stable isomers H₂BNSi, H₂NNSi, H₂PNSi and less stable isomers H₂BSiN, H₂NSiN, H₂PSiN. The effect of substituents on their structural properties has been discussed. The potential energy surfaces for the RSiN ? RNSi isomerization reactions have been analyzed. The structural properties of these molecules agree well with the theoretical values wherever available.     

Synthesis,characterization, and in vitro biological evaluation of highly stable diversely functionalized superparamagnetic iron oxide nanoparticles

In this article, we report the design and synthesis of a series of well-dispersed superparamagnetic iron oxide nanoparticles (SPIONs) using chitosan as a surface modifying agent to develop a potential T ₂ contrast probe for magnetic resonance imaging (MRI). The amine, carboxyl, hydroxyl, and thiol functionalities were introduced on chitosan-coated magnetic probe via simple reactions with small reactive organic molecules to afford a series of biofunctionalized nanoparticles. Physico-chemical characterizations of these functionalized nanoparticles were performed by TEM, XRD, DLS, FTIR, and VSM. The colloidal stability of these functionalized iron oxide nanoparticles was investigated in presence of phosphate buffer saline, high salt concentrations and different cell media for 1 week. MRI analysis of human cervical carcinoma (HeLa) cell lines treated with nanoparticles elucidated that the amine-functionalized nanoparticles exhibited higher amount of signal darkening and lower T ₂ relaxation in comparison to the others. The cellular internalization efficacy of these functionalized SPIONs was also investigated with HeLa cancer cell line by magnetically activated cell sorting (MACS) and fluorescence microscopy and results established selectively higher internalization efficacy of amine-functionalized nanoparticles to cancer cells. These positive attributes demonstrated that these nanoconjugates can be used as a promising platform for further in vitro and in vivo biological evaluations.     

Modulation of residual stress in diamond like carbon films with incorporation of nanocrystalline gold

Residual stress modulation in the diamond-like carbon coatings with incorporation of gold nanoparticles was studied critically. The films were deposited on glass and Si (1 0 0) substrates by using capacitatively coupled plasma chemical vapor deposition. Stresses in the films were determined from the broadening of the optical absorption tail and were found to decrease from 2.3 GPa to 0.48 GPa with increasing gold content (2-7 at.% Au) in the DLC matrix. Gold incorporation also made the films harder than the corresponding DLC coatings. Modulation of stress with nanocrystalline gold content in the DLC matrix was related to the relative amount of sp²/sp³ content in the DLC films.     

A possible connection between neutrino mass generation and the lightness of a NMSSM pseudoscalar

One of the interesting properties of the NMSSM is that it can accommodate a light pseudoscalar of order 10 GeV. However, such scenarios are challenged by several experimental constraints, especially those related to the fermionic decays of the pseudoscalar. In this Letter, we extend the NMSSM field content by two gauge singlets, with lepton numbers +1 and −1. This serves the twin purpose of generating neutrino masses via the inverse seesaw mechanism and keeping the option of a very light pseudoscalar experimentally viable by opening dominant invisible decay channels of the pseudoscalar which help it evade the existing bounds.     

Chaos suppression in a fractional order financial system using intelligent regrouping PSO based fractional fuzzy control policy in the presence of fractional Gaussian noise

Financial systems are known to have irregular and erratic fluctuations due to diverse influences and often result in economic crisis and huge financial losses. Recent models of financial systems show that they behave chaotically and have long range memory dependence. Mitigating these undesirable chaotic natures of financial systems by appropriate control policies is important in order to reduce investment risks and improve economic performance. In this paper, a fractional order fuzzy control policy is employed to suppress the chaotic dynamics of a representative chaotic fractional order financial system. An intelligent Regrouping Particle Swarm Optimization (Reg-PSO) is used to design the numeric weights of the control policy and the methodology is demonstrated by credible simulations. The designed fractional fuzzy control policies are shown to work well with respect to conventional fuzzy control policies in the presence of persistent and anti-persistent noise, which can be due to additional extraneous influences on the system.     

Monodromy for principal bundles

Given a strongly semistable principal bundle E_G over a curve, in Biswas et al. (2006) [4], a group-scheme for it was constructed, which was named as the monodromy group-scheme. Here we extend the construction of the monodromy group-scheme to principal bundles over higher dimensional varieties.     

Principal bundles on compact complex manifolds with trivial tangent bundle

Let G be a connected complex Lie group and G ì G{\Gamma \subset G} a cocompact lattice. Let H be a complex Lie group. We prove that a holomorphic principal H-bundle E _H over G/Γ admits a holomorphic connection if and only if E _H is invariant. If G is simply connected, we show that a holomorphic principal H-bundle E _H over G/Γ admits a flat holomorphic connection if and only if E _H is homogeneous.     

All particle primary nucleon spectrum derived from the latest jacee data

The all particle primary nucleon spectrum has been estimated on the basis of the latest Japanese American Emulsion Experiments on the balloon borne emulsion chamber measurements of the fluxes of p, He, C, N, O, Ne, Mg, Si, Fe and low energy fit extrapolated results have been found to follow the power law fit of the formN(E) dE=2·03E ^–2·7 dE (cm² s sr GeV/nucleon)^–1. The concept of nuclear fragmentation has been used to estimate the nucleon flux from nuclei spectra. The derived result agrees with the predicted primary spectrum after Yodh, Ellsworth, Stanev and Gaisser.Equipe de Recherche associée au C.N.R.S.Av. H. Fellow, on leave fromIndian Association for the Cultivation of Science, Jadavpur, Calcutta 700032, India.     

Few-valence-particle excitations around doubly magic 132Sn

Prompt γ-ray cascades in neutron-rich nuclei around doubly-magic ¹³²Sn have been studied using a ²⁴⁸Cm fission source. Yrast states located in the N = 82 isotones ¹³⁴Te and ¹³⁵I are interpreted as valence proton and neutron particle-hole core excitations with the help of shell model calculations employing empirical nucleon-nucleon interactions from both ¹³²Sn and ²⁰⁸Pb regions.