Exact (Born-Oppenheimer) 3-D numerical solutions of the time-dependent Schr?dinger equation are obtained for the one electron linear H+-H2+ atom-molecule system at large internuclear distance R in interaction with two-cycles intense (I>10(14) W cm(-2)) 800 nm laser pulses. High-order harmonic generation (HHG) spectra are obtained with an energy cutoff larger than the atomic maximum of I(p)+3U(p), where I(p) is the ionization potential and U(p) is the ponderomotive energy. At large R, this extended cutoff is shown to be related to the nature of electron transfer, whose direction is shown to depend critically on the carrier-envelope phase (CEP) of the ultrashort pulse. Constructive and destructive interferences in the HHG spectrum resulting from coherent superpositions of electronic states in the H+-H2+ system are interpreted in terms of multiple electron trajectories extracted from a time profile analysis. 相似文献
The authors have introduced and extended the sequential Bayesian Monte Carlo model discrimination (SBMCMD) method described in previous studies by Masoumi et al. for the purpose of discriminating between mechanistic models via designed experiments. The features of the Markov Chain Monte Carlo methods utilized in SBMCMD allow this method to work with a wide range of nonlinear models. Here, SBMCMD has been applied to simulated copolymerization systems to compare its performance with other statistical discrimination methods used in previous studies by Burke et al. In addition, the Hsiang and Reilly method has been reapplied to the same copolymerization systems to address questions arising from previous work on this subject. The results of applying the SBMCMD method show that it is possible to choose the best model correctly with fewer experiments compared to the previously studied methods. Results also confirm that copolymer composition data do not provide enough information to discriminate between terminal and penultimate data.
Textile materials can be treated with some enzymes to improve their functionality. The usual enzymatic treatment hydrolyzes the textile surfaces that leads to increase the functional groups. Here, the polyester/wool fabric as a blend of fibers fabric was selected and treated with the two different types of enzymes to increase the surface activity with a propose of higher nano-TiO(2) adsorption. The fabric was first treated with proteases and lipases to hydrolyze the wool and the polyester surfaces, respectively. It has been then dipped into an ultrasound bath containing nano TiO(2) and cross-linking agent followed by curing. The cross-linking agent, butane tetracarboxylic acid (BTCA), also assisted to enhance the nano-particles adsorption and stabilization on the fabric surface. The self-cleaning properties of the fabrics were examined through evaluating the color removal from the stained fabric with Acid Blue 113. The antibacterial properties were determined by reduction growth of a Gram-negative bacteria E. coli. and the UV protection was assessed by UV-reflectance spectrum. The SEM pictures and EDX spectrums of some samples were also reported. 相似文献
Pyrazolodithiones of expected biological activity were examined as thermal stabilizers and co-stabilizers for rigid poly(vinyl chloride) (PVC) in air at 180?°C. Their high stabilizing efficiency were shown by their high thermal stability values (Ts), which is the time needed for the liberation of HCl gas, if compared with dibasic lead carbonate (DBLC) and calcium?Czinc soap (Ca?CZn soap) reference stabilizers used industrially, with better extent of discoloration. Blending these derivatives with reference stabilizers in different ratios greatly lengthens the thermal stability value and improves the extent of discoloration of the PVC. The structure of the novel organic stabilizers was confirmed by elemental analysis, FTIR, Mass spectra, and 1H-NMR. Thermogravimetric analyses confirmed the improved stability of PVC in the presence of the investigated organic stabilizers, compared to blank PVC and PVC stabilized with the reference stabilizers. Also, GPC measurements were done to investigate the changes occurred in the molecular masses of the degraded samples of PVC in presence of the newly synthesized stabilizers. The stabilizing efficiency of pyrazolodithiones is attributed to the replacement of the labile chlorine atoms on the PVC chains by a relatively more stable moiety of the organic stabilizer. The investigated stabilizers showed a good antimicrobial activity toward two kinds of bacteria, Escherichia coli and Staphylococcus aureus; and also toward two kinds of fungi, Aspergillus flavus and Candida albicans. They also exhibited antitumor activity against both liver and colon human cell lines. 相似文献
In this paper, we study and discuss the structural, and electronic properties of the RbXF3 (X = Co, Mn, V or Fe) Perovskite Materials using the Density Functional Theory (DFT). Also, the origin of both semi-conductor (SM) and half-metallic (HM) characters have been outlined. The density functional theory (DFT) has been applied to illustrate the physical properties of the RbXF3 (X = Co, Mn, Fe or V) perovskite materials. The generalized gradient approximation introduced by Perdew–Burke and Ernzerhof (GGA-PBE) with Hubbard correction has been used for modeling the physical properties of the RbXF3 (X = Co, Mn, V or Fe) perovskite compounds. The total and partial densities of states of each solar perovskite RbVF3 (X = Co, Mn, Fe or V) material have been illustrated and discussed. In addition, the contribution of the different elements: Rb, Co, Mn, Fe, V and F, has been investigated revealing the most contributing ones in the valance and conduction bands. The magnetic behavior of the studied solar perovskites RbVF3 (X = Co, Mn, Fe or V) materials, has been outlined. It is found that the perovskites RbCoF3 and RbFeF3 are half-metallic, while the materials RbMnF3 and RbVF3 exhibit a semi-conductor behavior. 相似文献
The ability to fabricate tapered microchannels with customizable cross sections in a variety of materials is highly desirable for microfluidic applications. This article examines ultrafast laser machining of tapered microchannel trenches in both hard (soda-lime and borosilicate glasses) and soft (PDMS elastomer) transparent solids. A simple model for channel width and depth as a function of processing parameters and threshold fluence is presented. Estimated channel sizes from the model are in good agreement with experimental results. We also show that the channel depth is a linear function of the number of laser pulses per channel width. All measurement data are found to collapse onto a single curve, which can serve as a useful guide for micromachining of tapered channels in transparent materials. 相似文献
A new dioxo-molybdenum(VI) complex [MoO2(L)(CH3OH)] has been synthesized, using 2-[(2-hydroxypropylimino)methyl]phenol as tridentate ONO donor Schiff base ligand (H2L) and MoO2(acac)2. A monoclinic space group P21/c was determined by X-ray crystallography from single-crystal data of this complex. The high catalytic activity of this new Schiff base complex has been observed in the oxidation of various sulfides by urea hydrogen peroxide in ethanol affording sulfoxides and sulfones using different molar ratio of oxidant/sulfide in high/excellent yields and selectivity under mild and eco-friendly conditions. The relative high stability and desired turnover numbers have been observed for this Mo-catalyst in the oxidation reactions. 相似文献