A rapid and efficient method for synthesis of new 3-arylideneisobenzofuran-1(3H)-one derivatives catalyzed by acetic anhydride under solvent-free and microwave conditions

In this study we have described the synthesis of new 3-arylidene isobenzofuran-1(3H)-one derivatives. Condensation reaction of phthalic anhydride and quinoline derivatives under solvent-free condition and microwave irradiation in the presence of acetic anhydride as catalyst in good excellent yield is reported.     

One-pot multicomponent synthesis of indol-3-yl-hydrazinyl thiazoles as antimicrobial agents

A series of novel mono- and bis(indol-3-yl)hydrazinyl thiazole derivatives were efficiently synthesized via one-pot cyclocondensation of mono- or bis(indole-3-carbaldehyde), thiosemicarbazide, and phenacyl bromides. The structure of the products was confirmed by Fourier-transform infrared (FT-IR), ¹H nuclear magnetic resonance (NMR), and ¹³C NMR spectra. All synthesized compounds were evaluated for in vitro antibacterial activity against Gram-positive (Bacillus subtilis and Micrococcus luteus) and Gram-negative bacteria (Pseudomonas aeruginosa and Salmonella enteritis). Among the compounds screened, a few were found to be highly effective antibacterial agents. The bis-compounds with OCH₃ donating group exhibited good activity against the Gram-positive bacteria.     

Chiral Bag Model with Constituent Quarks: Topological and Nontopological Solutions

We consider a three-phase modification of the hybrid chiral bag model involving the intermediate constituent quark phase along with the asymptotic freedom and hadronization phases. We find self-consistent solutions of the equations of the model in 1+1 dimensions with the fermion vacuum polarization effects taken into account. We study the renormalized total energy of the bag as a function of parameters characterizing the geometry of the bag and its topological (baryon) charge. We show that for a nonzero topological charge, there exists an entire series of configurations that are local minimums of the total energy of the bag and contain all the three phases, whereas in the nontopological case, the bag energy minimum corresponds to zero sizes of the domain of the asymptotic freedom phase.     

QND measurements for future gravitational-wave detectors

Second-generation interferometric gravitational-wave detectors will be operating at the Standard Quantum Limit (SQL), a sensitivity limitation set by the trade off between measurement accuracy and quantum back action, which is governed by the Heisenberg Uncertainty Principle. We review several schemes that allows the quantum noise of interferometers to surpass the SQL significantly over a broad frequency band. Such schemes may be an important component of the design of third-generation detectors.     

Three-Body Calculation of the 4He（aH,γ）7Li and 4He（aHe,γ）7Be Reactions and Structure of the 7Li and 7Be at Solar Energies

The two 3H＋4He and 3He＋4He fusion reactions at low energies are usually viewed as an approximate external capture process. We study the 4He（3H,γ）rLi and 4He（SHe,γ）7Be reactions in a cluster model, which can take into account two- and three-body electromagnetic currents, using minimal substitution in the explicit momentum dependence of the two- and three-cluster interactions. Our main goal is to explore how the cross section of the low-energy 3H＋4He or 3He＋4He capture reactions depends on energy. The astrophysical S-factors for these reactions are calculated at very low energies. We construct the conserved realistic Argonne v18 for two nucleons and Urbana IX or Tucson-Melbourne three-cluster interactions, which are considered for calculation. We also calculate the binding energies and the structural properties of a Hq-4He or 3He＋4 He systems. The binding energies are found to be -37.72 （-36.32） MeV and -39.35 （-37.43） MeV, with （without） three-body interactions for 7Be and 7 Li, in satisfactory agreement with other theoretical results and experimental data, respectively.     

Astrophysical S-factor of the d(p,γ)~3 He process by effective field theory

We summarize the recent effective field theory (EFT) studies of low-energy electroweak reactions of astrophysical interest, relevant to big-bang nucleosynthesis. The zero energy astrophysical S(0) factor for the thermal proton radiative capture by deuteron is calculated with pionless EFT. The astrophysical S(0) factor is accurately determined to be S(0)=0.243 eV·b up to the leading order (LO). At zero energies, magnetic transition M1 gives the dominant contribution. The M1 amplitude is calculated up to the LO. A good, quantitative agreement between theoretical and experimental results is found for all observables. The demonstrations of cutoff independent calculation have also been presented.     

Ultrasound-promoted an efficient method for one-pot synthesis of 2-amino-4,6-diphenylnicotinonitriles in water: a rapid procedure without catalyst

A green and convenient approach to the synthesis of 2-amino-4,6-diphenylnicotinonitriles via four-component reaction of malononitrile, aromatic aldehydes, acetophenone derivatives and ammonium acetate in water under ultrasound irradiation is described. The combinatorial synthesis was achieved for this methodology with applying ultrasound irradiation while making use of water as green solvent. In comparison to conventional methods, experimental simplicity, good functional group tolerance, excellent yields, short routine, and selectivity without the need for a transition metal or base catalyst are prominent features of this sonocatalyzed procedure.     

Localized Frames and Compactness

We introduce the concept of weak localization for continuous frames and use this concept to define a class of weakly localized operators. This class contains many important classes of operators, including: short time Fourier transform multipliers, Calderon–Toeplitz operators, Toeplitz operators on various functions spaces, Anti-Wick operators, some pseudodifferential operators, some Calderon–Zygmund operators, and many others. In this paper, we study the boundedness and compactness of weakly localized operators. In particular, we provide a characterization of compactness for weakly localized operators in terms of the behavior of their Berezin transforms.     

Characterization of the alternating groups by their order and one conjugacy class length

Let G be a finite group, and let N(G) be the set of conjugacy class sizes of G. By Thompson’s conjecture, if L is a finite non-abelian simple group, G is a finite group with a trivial center, and N(G) = N(L), then L and G are isomorphic. Recently, Chen et al. contributed interestingly to Thompson’s conjecture under a weak condition. They only used the group order and one or two special conjugacy class sizes of simple groups and characterized successfully sporadic simple groups (see Li’s PhD dissertation). In this article, we investigate validity of Thompson’s conjecture under a weak condition for the alternating groups of degrees p+1 and p+2, where p is a prime number. This work implies that Thompson’s conjecture holds for the alternating groups of degree p + 1 and p + 2.