A Continuous-Wave Ho：YA103 Laser with Output 8.5 W Pumped by a 1.91μm Laser at Room Temperature

A cw high efficient Ho：YAI03 laser pumped by 1.91 μm diode-pumped Tm：YLF laser at room temperature is realized. The maximum output power reaches 8.5 W when the incident pump power is 15.6 W. The slope efficiency is 63.7%, and the Tm：YLF to Ho：YAP optical conversion efficiency is 54.5%. The laser wavelength is 2118.3nm when the transmission of output coupler is 30%. The beam quality factor is M2 -1.39 measured by the traveling knife-edge method.     

High-resolution Fourier transform study of the ν3 fundamental band of trans-formic acid

Using high-resolution Fourier transform spectra of trans-HCOOH recorded at 5.6 μm, we carried out an extensive analysis of the strong ν₃ fundamental band (carbonyl stretching mode) at 1776.83 cm^?1, starting from results of a previous analysis [Weber WH, Maker PD, Johns JWC, Weinberger E. J Mol Spectrosc 1987; 121: 243–60]. As pointed out in the literature, the ν₃ band is significantly perturbed by resonances due to numerous dark bands. We were able to assign series belonging to the ν₅+ν₇, ν₅+ν₉, ν₆+ν₇ and ν₆+ν₉ dark bands, located at 1843.48, 1792.63, 1737.96 and 1726.40 cm^?1, respectively. The model used to calculate energy levels accounts partly for the observed resonances, and enabled us to reproduce most of the observed line positions, within their experimental uncertainties. We also determined absolute line intensities with an accuracy estimated to 15%. Finally, we generated, for the first time, a list of line parameters for the 5.6 μm region of trans-formic acid.     

Self and N2 collisional broadening of far-infrared methane lines measured at the SOLEIL synchrotron

Following our recent study devoted to measurements of intensities of pure rotation lines of methane, room temperature far infrared spectra of methane diluted in nitrogen at five total pressures between 100 and 800 hPa have been recorded at the AILES beamline of the SOLEIL synchrotron. One hundred and five N₂ broadening coefficients of methane pure rotation lines have been measured in the 83–261 cm^?1 spectral range using multi-spectrum non-linear least squares fitting of Voigt profiles. Pressure-induced line shifts were not needed to fit the spectra to the noise level and line mixing effects were neglected. One hundred and seventy-six self broadening coefficients have also been measured in the 59–288 cm^?1 spectral range using the pure methane spectra recorded in our previous work. The measured N₂ broadening coefficients were compared to semi-classical calculations.     

Kinetics and mechanism of the pyrolysis of 1-chloro-1,1-difluoroethane in the presence of additives

The thermal dehydrochlorination CF₂ClCH₃→CF₂(DOUBLEBOND)CH₂+HCl has been studied in a static system between 597 and 664 K in the presence of CCl₄, C₂Cl₆, CF₂(DOUBLEBOND)CH₂, HCl, and CF₃CH₃. A kinetic radical and molecular reaction model has been developed. In addition to describing earlier results on the acceleration of the pyrolysis by CCl₄ and the further acceleration by HCl, this model describes quantitatively up to conversions of 20% (i) the dependence of the catalytic effect of CCl₄ at low concentrations, (ii) the stronger catalytic effect of C₂Cl₆, and (iii) the inhibitory effect of added CF₂CH₂ and CF₃CH₃ when CCl₄ is used as a catalyst. © 1998 John Wiley & Sons, Inc. Int J Chem Kinet 30: 359–366, 1998     

CO2 pressure broadening and shift coefficients for the 1–0 band of HCl and DCl

CO₂ broadened spectra of the 1–0 band of H³⁵Cl and H³⁷Cl, observed near 2886 cm^?1, and the 1–0 band of D³⁵Cl and D³⁷Cl, located near 2089 cm^?1, have been recorded at room temperature and five total pressures between 150 and 700 Torr, using a Bruker IFS125HR Fourier transform spectrometer. Spectra of pure HCl were also recorded. CO₂ broadening and shift coefficients of HCl and DCl have been measured using multi-spectrum non-linear least squares fitting of Voigt profiles. The analysis of the 1–0 band of DCl was complicated by the presence of overlapping CO₂ bands, which were included in the treatment as absorption coefficients calculated taking line-mixing effects into account.     

地方高校化工专业学生创新创业能力提升模式探索

针对当前地方高校化工类专业创新创业人才供需现状,结合地方高校实际,提出了化工专业学生虚拟公司设计实训、校内仿真实训、校内外实践基地一体化创新创业能力提升实践教学模式,具有"内外结合、虚实结合、阶梯式推进"等特色。经探索,采用该模式可走出一条具有地方高校特色的实践教学新路径,可形成工科专业实践教学的示范模式,对于提升地方高校的竞争力具有积极意义。