合成氨煤气炉DCS数据建模与统计分析

利用相关系数阵的条件数研究影响煤气炉上部温度的各影响因素之间的复共线性,利用对数回归方法建立煤气炉上部温度与各影响因素之间的线性回归模型。经检验回归方程与回归系数均具有良好的显著性.所建模型对改善炉况,保持生产过程持续稳定具有现实指导意义。     

带阻尼项一维非等熵流方程组初边值问题解的收敛速度

研究了带阻尼项一维非等熵流方程组的初边值问题，利用能量估计的办法证明了整体解的存在性和得到在L2－模及L∞－模意义下解的大时间状态稳定性估计。     

Stationary-phase focusing in capillary gas-liquid chromatography: Enhancement of the maximum permissible sample size

Equations have been derived to predict the extent to which the sample size may be increased, without decreasing the column performance, by stationary-phase focusing at sub-ambient temperatures. Under favorable circumstances the sample size may be enhanced several hundredfold.     

环上的模糊理想幂格及其强截集诱导的格

给出了环上模糊理想幂格的概念,得到相关性质。进而由环上模糊理想强截集诱导出格,讨论了它不是分配格,但为模格。同时,将环上升为主理想环,得到了模糊理想乘积的强截集等于强截集的乘积,且都为环的理想。最后,讨论了Boolean环的模糊子集为模糊理想与其伴随构成交半格的关系。     

Determination of the configuration of histrelin,and LHRH analog,by chiral capillary gas chromatography

Summary Summary The assigned chirality at each center of the synthetic nonapeptide histrelin (L-pyroglutamyl-L-histidyl-L-tryptophyl-L-seryl-L-tyrosyl-D-N^im-benzyl-histidyl-L-leucyl-L-arginyl-L-proline-ethylamide) was verified using chiral gas chromatography. The procedure involved acid hydrolysis of histrelin to the constituent amino acids, derivatization as the N-pentafluoropropionyl/isopropyl esters and the analysis of the mixture using a commercially available 25m chiral capillary column (Chirasil-L-Val). There was no significant difference in the retention time of the amino acids obtained from the hydrolysate mixture when compared to the appropriate standards. Additionally, the hydrolysate was spiked with the D and L amino acids to prove the identity of closely eluting peaks. Luteinizing hormone-releasing hormone     

High-precision nonperturbative QCD

Recent advances in lattice QCD have resulted in the first simulations with realistic quark vacuum polarization. Consequently a wide variety of high-precision (few percent) nonperturbative calculations are possible now. This paper reviews the recent developments that make this possible, and presents early evidence that the era of high-precision nonperturbative QCD is at hand. It also discusses the future impact of lattice QCD on experiments, and particularly for heavy-quark physics.     

Rotational spectra, nuclear quadrupole hyperfine tensors, and conformational structures of the mustard gas simulent 2-chloroethyl ethyl sulfide

Rotational spectra have been recorded for both the ³⁵Cl and ³⁷Cl isotopic forms of two structural conformations of 2-chloroethyl ethyl sulfide (CEES). The rotational constants of the ³⁵Cl and ³⁷Cl isotopomers were used to identify the conformational isomers. A total of 236 hyperfine transitions have been assigned for 47 rotational transitions of the ³⁵Cl isotope of a GGT conformer, and 146 hyperfine have been assigned for 37 rotational transitions of the ³⁷Cl isotopomer. For the second conformer, a total of 128 (110) hyperfine and 30 (28) rotational transitions have also been assigned to the ³⁵Cl (³⁷Cl) isotopes of a TGT conformation. The extensive hyperfine splitting data, measured to high resolution with a compact Fourier transform microwave spectrometer, were used to determine both the diagonal and off-diagonal elements of the ³⁵Cl and ³⁷Cl nuclear quadrupole coupling tensors in the inertial tensor principal axis system. The experimental rotational constant data, as well as the ³⁵Cl and ³⁷Cl nuclear quadrupole coupling tensors, were compared to the results from 27 optimized ab initio (HF/6-311++G^∗∗ and MP2/6-311++G^∗∗) model structures.     

The role of adsorption phenomena in capillary gas-liquid-solid chromatography

The method of invariant relative retention value determination using commerciallly produced fused silica open-tubular columns with different contents of stationary liquid phase has been tested. Invariant retention values are determined only by interaction of analyzed compound with stationary liquid phase and are independent of the adsorptive interactions in the studied system.