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1.
本文用变分过渡态理论,首次对无鞍点的释能反应O+CS→CO+S、O+CO→CO+O和S+CS→CS+S进行了动力学研究,考察了反应动力学瓶颈区性质,计算了反应的速度常数,并将O+CS反应的速度常数值与实验值及经典轨迹计算结果进行了比较,三者基本相符.  相似文献   
2.
以"H"型电池为主体装置,考察和比较了有机和无机碳源对产甲烷生物阴极启动期和稳定运行期性能的影响.结果表明,有机碳源可以加速产甲烷生物阴极的形成,并使其在稳定运行期维持较高的运行性能;有机碳源条件下所形成的产甲烷生物阴极具有较好的电化学活性,当阴极电势为-0.75 V(vs.SHE)时,其电流密度可达(2.34±0.15)A/m2;通过投加有机碳源,可以实现CO2(或HCO-3)的原位供给,与无机碳源直接供给方式相比,可在一定程度上缓解气液传质限制,提高微生物的生长速率,最终使产甲烷生物阴极表面生物量是无机碳源培养下的4倍多.从微生物分析角度解释了有机碳源提高产甲烷生物阴极性能的原因.  相似文献   
3.
Rotational spectra of four rare isotopic species of OCS were observed in the 110-690 GHz region with a source-modulated submillimeter-wave spectrometer. Spectral lines of 18O13CS, O13C36S, 18OC36S, and 18O13C34S were measured in their natural abundances, 21.4, 1.51, 0.29, and 0.95 ppm, respectively. The rotational constants and centrifugal distortion constants were precisely determined from observed line frequencies by least squares methods. In order to facilitate sensitivity examination in the submillimeter-wave region, transition frequencies and peak absorption coefficients were calculated and tabulated for the spectral lines of the four species up to the 1000 GHz region.  相似文献   
4.
In the wavelength range of 231-275 nm, we have studied the mass-resolved dissociation spectra of OCS+ via B2+←X23/2(000) and B2+←X21/2(000, 001) transitions by preparing OCS+ ions in the well-defined spin-orbit states. The spectroscopic constants ofυ1(CS stretch)=828.9 (810.4) cm-1, υ2(bend)=491.3 cm-1 and υ3(CO stretch)=1887.2 cm-1 for OCS+(B2+) are deduced. The observed dependence of the υ2(bend) mode excitation of B2+ on the spin-orbit splitting of X2∏(Ω=1/2, 3/2) in the B2+←X2∏ transition can be attributed to the K coupling between the (000)21/2 and (010)2+1/2 vibronic levels of X2∏ state, which makes the B2+(010)←X21/2(000) transition possible.  相似文献   
5.
In this paper, we report measured Rosenkranz N2- and O2-broadening, induced pressure-shift and mixing coefficients for OCS in the ν1 + ν3 band, using a multi-pressure fitting technique applied to the measured shapes of the lines, including the interference effects caused by the line overlaps. These measurements were made by analysing six laboratory absorption spectra recorded at 0.004 cm?1 resolution using the Fourier transform spectrometer Bruker IFS125HR located at the Laboratoire Interuniversitaire des Systèmes Atmosphériques, in Créteil. The spectra have been recorded in the 1850–3000 cm?1 wave number range at 295 K, using a multipass absorption cell with an optical path of 3.249 m. The total sample pressures ranged from 5.97 to 83.28 Torr with OCS volume mixing ratios between 0.001 and 0.013 in nitrogen or oxygen. We have been able to determine the N2- and O2-pressure-broadening coefficients of 81 ν1 + ν3 transitions with rotational quantum number J up to 50. The measured N2- and O2-broadening coefficients range from 0.0815 ± 0.0698 to 0.1169 ± 0.1027 cm?1 atm?1 at 295 K, respectively. Most of the measured pressure shifts are positive. The reported N2- and O2-induced pressure-shift coefficients vary from about ?0.0103 ± 0.0092 to 0.0097 ± 0.0092 cm?1 atm?1, respectively. We have examined the dependence of the measured broadening parameters on the quantum number m (m = ?J for the P branch and m = J + 1 for the R branch) and also developed an empirical expression to describe the broadening coefficients in terms of |m|. On average, this empirical expression reproduces the measured broadening coefficients to within 2%. Using a semi-classical Robert and Bonamy formalism, the theoretical broadening coefficients have been calculated at room temperature and compared with the experimental results. The theoretical results of the broadening coefficients are in very good overall agreement with the experimental data (2%).  相似文献   
6.
 Ab initio calculations have been performed to study the molecular structures and vibrational levels of the four low-lying ionic states (1, 22Π, and 1, 22Σ+) of carbonyl sulfide. The global regions of the potential-energy surfaces have been obtained by multireference single and double excitation configuration interaction calculations. Vibrational calculations using explicit vibrational Hamiltonians have been used for vibrational analysis. The equilibrium molecular structures and a vibrational analysis of the four ionic states are presented. The theoretical ionization intensity curves including the vibrational structures of the ionic states are also presented and are compared with the photoelectron spectrum. Received: 20 January 2001 / Accepted: 22 August 2001 / Published online: 30 October 2001  相似文献   
7.
    
Heterodyne frequency measurements have been made on the 12°0-00°0 band of carbonyl sulfide in the wavenumber range from 1866 to 1915 cm–1. Frequency measurement techniques reported earlier are used to measure the OCS absorption lines by means of a tunable diode laser, a CO laser local oscillator, and two CO2 lasers used as secondary frequency standards. A table of calculated absorption frequencies is given for OCS from 1866 to 1919 cm–1.  相似文献   
8.
反射相移对光学玻璃电流传感器抗电磁干扰能力的影响   总被引:1,自引:0,他引:1  
孙伟民 Ning.  YN 《光学学报》1998,18(9):249-1254
在光学玻璃电流传感器中,如果光线反射转向时在光的p,s分量之间引入反射相移,则会对该传感器的抗电磁干扰能力产生不良影响,本文对这种情况进行了理论上的分析,并给出了数值模拟和实验的结果。  相似文献   
9.
OCS表面活性剂在弱碱、无碱条件下的界面张力性能研究   总被引:6,自引:0,他引:6  
研究了OCS表面活性剂中试产品在弱碱NaCO33及无碱条件下应用于不同油田原油的油-水界面张力特性。结果表明:对于大庆采油四厂原油,当表活剂浓度为0.1%-0.3%,Na2CO3浓度为0.6%-1.2%时,油-水界面张力可达到超低(-l0^-3mN/m数量级);对于大庆采油二厂原油,当表面活性剂浓度为0.1%-0.3%,Na2CO3浓度为0.8%-1.4%时,油-水界面张力可达到超低;对于华北油田古-联原油,当表面活性剂浓度为0.2%,NaCO3浓度为0.6%-1.2%时,油-水界面张力可达到超低;对于胜利油田孤东采油厂原油,当表面活性剂浓度为0.2%,NaCO3浓度为0.8%-1.4%时,油-水界面张力可达到超低。在无碱条件下,对于大港油田枣园1256断块原油,当OCS表面活性剂浓度达到0.1%时,油-水界面张力即可达到超低;对于江苏油田原油,当OCS表面活性剂浓度在0.1%以上时,油-水界面张力均可以达到10^-2mN/m数量级。聚丙烯酰胺聚合物的加入对油-水超低界面张力的形成和稳定具有促进作用。  相似文献   
10.
在超声分子束条件下,由423、420、412.2和408.4nm的电离激光使OCS分子通过[3+1]共振增强多光子电离(REMPI)制备出OCS+(X2Π)离子后,在260-325nm范围内扫描解离激光获得了OCS+离子经由A2Π3/2←X2Π3/2(000)和A2Π1/2←X2Π1/2(000,001)跃迁的分质量光解离谱(母体离子OCS+的凹陷谱和碎片离子S+的增强谱).其中A2Π1/2←X2Π1/2(001)跃迁的光解离谱是首次观察到.由A2Π3/2←X2Π3/2(000)光解离谱得到了A2Π3/2电子态的光谱常数T0=31411.3cm-1,ν1=814.3cm-1;由A2Π1/2←X2Π1/2(000)光解离谱得到了A2Π1/2电子态的光谱常数ν1=816cm-1,ν2=(380.4±2.8)cm-1,ν3=(2052.7±5.1)cm-1,而从A2Π1/2←X2Π1/2(001)光解离谱拟合出的A2Π1/2电子态的ν1(786.4cm-1)稍有不同,表明在A2Π1/2←X2Π1/2(001)跃迁中X2П1/2电子态的C-O键振动(ν3)激发影响了A2Π1/2电子态C-S键的振动(ν1).实验结果表明:在A2Π1/2←X2Π1/2(000,001)跃迁的光解离谱中能够显著观察到属于A2Π电子态的ν2弯曲振动模激发的谱峰,例如A2Π1/2(020,120,021,…),而在A2П3/2(υ1υ2υ3)←X2Π3/2(000)跃迁的光解离谱中几乎没有观察到属于ν2弯曲振动模激发的谱峰.这种弯曲振动激发和A2П电子态的旋轨分裂分量(Ω)的相关性可以通过A2Π电子态的Fermi共振和Renner-Teller效应来解释.  相似文献   
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