The study of the multiphoton ionization of methyl iodide has a long and storied history. Here, we revisit this topic and present spectra of each of the photoionization and photodissociation fragments ($C^{+},$ $CH^{+},$ $CH_{2}^{+},$ $CH_{3}^{+},$ $CH_{3}I^{+},$ and $I^{+}$) using a custom time-of-flight mass spectrometer and a tunable dye laser over the excitation range of 550-740 nm (2.2-1.67 eV). The choice of this wavelength range allows for excitation through the $A$ state and resonant ionization through higher energy levels using 4+1, 5+1, or 6+1 photons for excitation and ionization.  Although the various fragments yield very similar spectra, fewer fragment ions are observed with increasing wavelength.

Ultrafast photodissociation dynamics of n-butyl iodide in the $A$-band has been studied by femtosecond time-resolved mass spectroscopy coupled with ion imaging. The time constant of $n$-$C_4H_9I$ in the A-band with one photon excitation at ~267 nm is measured to be ~(58$\pm$6) fs. The ion images of $I (^2P_{3/2})$ and $I^* (^2P_{1/2})$ at ~267 nm and ~274 nm are obtained and analyzed to yield corresponding speed and angular distributions. The dependences of dissociation mechanism on excitation wavelength and the size of the alkyl radical are discussed.

Electron impact ionization cross sections (EIICS) of K-shell have been evaluated for light atoms (C, N, O) at incident energies ranging from ionization threshold to 1 GeV. The plane wave Born approximation is used in the proposed model by incorporating it in exchange, coulomb and relativistic effects along with the contributions of transverse interaction to ionization cross sections. In present model, we require two constants for each atom, ionization energy $(I)$ and the electron occupation number $(N).$ Adequate comparisons have been made with other theoretical methods, empirical formulae. The predicted EIICS of K-shell also compared with experimental data. Obtained results are in good agreements with available experimental data.

Batch experiments are carried out for the sorption of cationic dyes such as crystal violet, Malachite green and Rhodamine B dyes onto corncob acid treatment. The operating variables studied are contact time and pH. Equilibrium adsorption isotherms and kinetic were investigated. The experimental data were analyzed by the Langmuir and Freundlich models and the isotherm data fitted well to the Langmuir isotherm. The kinetic data obtained were analyzed using a pseudo-first order and pseudo-second-order equation and intra particle diffusion equation. The experimental data fitted very well the pseudo-second-order kinetic model.

The geometries, stabilities, electronic, and magnetic properties of $Au_{n}Sc_{m}$ $(n=1-7,$ $m=1,2)$ clusters have been systematically investigated by density functional theory. It is shown that the most stable structures of $Au_{n}Sc (n=1-7)$ clusters favor planar structure and $Sc$ atom is prone to occupy the center site of $Au$ atoms ring. For $Au_{n}Sc_{2}$ clusters, the 3d configurations become the lowest energy structure for $n\geq3;$ the growth is based on triangle bipyramid structure of $Au_{3}Sc_{2}$ cluster except $Au_{4}Sc_{2}.$ The second-order energy difference and the fragmentation energy show $Au_{3}Sc,$ $Au_{5}Sc,$ $Au_{3}Sc_{2}$ and $Au_{6}Sc_{2}$ clusters possess relatively higher stabilities than their neighbor size. The doping of $Sc$ atom can greatly improve the stability of $Au$ clusters. The doped one $Sc$ atom changes the odd-even alternation trend of gaps in $Au_{n}.$ The two doped-Sc atoms enhance chemical activity of $Au_{n}$ in most cases. The total magnetic moments with even valence electrons are quenched on the whole due to electron pairing effects. The averaged coordination number for Sc should be major reason for reduce of local magnetic moments of $Sc$ atom with cluster size increasing in cluster with odd valance electrons. The total magnetic moments in $AuSc$ and $Au_{2}Sc_{2}$ are no quenched due to the smaller coordination number, the charge transfer and weak hybridization between the $Sc$ and $Au$ atoms.

We investigate the rotational wave packet modified by femtosecond laser pulses. The calculations are performed by solving numerically the full time-dependent Schrödinger equation for the $N_2$ molecule at finite rotational temperature. It is demonstrated that the rotational wave packet induced by the first laser pulse can be controlled exactly just by selecting the optimal time at which the second laser pulse is introduced. Whether the pulse duration of the two lasers is equal or not, the molecular alignment induced by the first laser pulse can be enhanced or degraded by precisely inserting the peak of the second laser pulse at the maximum or minimum position of the slope curve for the alignment parameter by the first laser. Furthermore, the already enhanced alignment by the two lasers can be enhanced or degraded by precisely inserting the peak of the third laser at the maximum or minimum position of the slope curve for the alignment by the two lasers. The already degraded alignment by the two lasers can be increased again from the isotropic distributed ensemble by precisely inserting the peak of the third laser at the peak position of the slope curve by the two lasers.

As for two kinds of entangled coherent states, we have studied the relationship between the entanglement and the nonclassical effects; we calculate their entanglement by the concurrence and their nonclassical effects, such as squeezing and antiquating. We find that the entanglement always corresponds with one of squeezing and antiquating and the larger a nonclassical effect is, the stronger entanglement is. The result shows the entanglement has a deep relationship with the nonclassical effects.

The transverse Stark shift of the electronic energy levels in GaAs semiconducting quantum box is investigated by the use of variational solutions to the effective-mass approximation. It is found an interesting phenomenon that the largest Stark shift is obtained for the electric field directed along the diagonal in cross section of a quantum box, while for a rectangular one, the shift reaches peak value for the low field directed along a side of cross section and for the high field along the diagonal. Likewise, the conclusion is shown that the transverse Stark shift in a quantum box depends highly on the ratio of cross sectional sides while is irrelevant to its height. The large Stark shift of the electron and hole trapped in a quantum box leads to an obvious reduction of the interband recombination and wide irradiance spectrum.

The geometrical structure of flue gas $^{32}S^{16}O_2$ and $^{34}S^{16}O_2$ molecule have been optimized at B3P86/cc-PV5Z level using Gaussian03 program, we gain their equilibrium geometry, resonance frequency and rotational constants et al.. The total internal partition functions are calculated at the temperatures from 70 K to 6000 K for $^{32}S^P{16}O_2$ and $^{34}S^{16}O_2$ with the product approximation. Thereinto, the rotational partition sums $Q_{rot}$ adopt the WATSON rigid rotator model, which take into account centrifugal distortion corrections. The vibrational partition sums $Q_{vib}$ use the harmonic oscillator approximation model. It is found that the calculated total internal partition functions are consistent with those offered by HITRAN database from 70 K to 3000 K, and the errors shows linear correlation approximately. By fitting the errors, the total internal partition functions values at high temperature range of 3000 K to 6000 K were corrected. The corrected total internal partition functions are fitted to a four-order polynomial expression in $T,$ and the coefficients are gained at high temperature. This allows a rapid and accurate calculation of the total internal partition functions at the temperature from 3000 K to 6000 K.

A more general algebraic expression for the calculation of the four-mode Franck-Condon factors was derived straightforwardly on the basis of the closed form expression of the Franck-Condon integrals between arbitrary multidimensional harmonic oscillators under the Duschinsky mixing effects. This new algebraic expression was applied to study the photoelectron spectra of $D_2CO^+(\widetilde{A} ^2B_1).$ Franck-Condon analyses and spectral simulations were carried out on the $D_2CO^+(\widetilde{A} ^2B_1)$-$D_2CO(\widetilde{X} ^1A_1)$ photoionization processes. The spectral simulations of vibrational structures based on the computed Franck-Condon factors are in excellent agreement with the observed spectra.