Application of partial least square on quantitative analysis of L-, D-, and DL-tartaric acid by terahertz absorption spectra

Absorption spectra of polycrystalline L-, D-, and DL-tartaric acid have been measured by terahertz time domain spectroscopy (THz-TDS). Different absorption bands are observed for DL-tartaric acid and its enantiomers (L- and D-tartaric acid). This result shows that the THz-TDS can be used for distinguishing between DL-tartaric acid and enantiomers (L- and D-tartaric acid). Moreover, partial least square (PLS) can be found to improve the quantitation of L-tartaric acid in L- and DL-tartaric acid mixture by THz-TDS.     

负载金催化剂上CO氧化反应活性与金属氧化物载体中金属-氧结合能之间的关系

讨论了金属氧化物载体(MOx)对其负载纳米金催化剂(Au/MOx)上CO氧化反应的影响。采用典型的共沉淀法和沉积-沉淀法在完全相同的焙烧条件下制备了一系列MOx负载金催化剂,以CO氧化转化50%时的反应温度(T1/2)定量评价了MOx载体和Au/MOx催化剂的催化活性。进一步将MOx载体与相应Au/MOx催化剂的T1/2值之差对MOx载体的金属-氧结合能做曲线进行关联,发现二者呈明显的火山型关系。这一结果表明,采用具有适当金属-氧结合能(300–500 atom O)的MOx可大大提高沉积于其上的Au纳米颗粒的催化活性。     

Quantum ergodic channels in operator algebras

The quantum ergodic channel is studied by operator algebraic methods. The ergodic and KMS channels are introduced and their dynamical properties are discussed.     

Spectroscopic study of 75Se by the (d,p) reaction

The (d, p) reaction on ⁷⁴Se was investigated with 6.0 MeV deuterons. Many new levels of the ⁷⁵Se nucleus were found up to 4.7 MeV excitation energy. From a DWBA analysis of the cross sections and the angular distributions, spectroscopic factors and l_n values were obtained for forty levels. A sum rule analysis was applied to the results and the emptiness of low-lying shell model states was extracted.     

Reactions of 2‐Pentynyl trimethylsilylethynyl selenides with primary amines via allenyl selenoketene

Reactions of 2‐pentynyl trimethylsilylethynyl selenide 3 with primary amines 5 via allenyl selenoketene 4 afforded the corresponding selenine 6 , selenophene 7 and β,γ‐unsaturated selenoamide 8 , respectively.     

Theoretical studies on the molecular dependence of the bond dissociation after the core excitations. CH3OCO(CH2)nCN, n=0, 1, 2

Approximate theoretical normal and resonant Auger spectra for a series of methyl cyanoesters were calculated. To study the reported molecular dependence of the fragmentation patterns after the core excitations, a new measure, bond dissociation factor, was introduced. The site-selectivity and the state-specificity for a series of methyl cyanoesters are qualitatively explained.     

Photoelectron diffraction effects in XPS angular distributions from GaAs(110) and Ge(110) single crystals

Angular distribution measurements of XPS intensities have been made for various spectral lines from GaAs(110) and Ge(110) single-crystal surfaces. Observed angular distribution curves (ADC's) showed steep intensity variations and sharp peaks due to X-ray photoelectron diffraction (XPED) phenomena. The effects of the type of transition process (photoelectron or Auger), electron kinetic energy and crystal structure on the XPED patterns were examined. Considerably different ADC patterns were observed for high-energy photoelectrons and Auger electrons and for low-energy photoelectrons. ADC's for Ga 3d, As 3d and Ge 3d showed almost the same patterns for scans of the type [110] → [100] → [1$\text{1}$0], but they showed substantially different patterns for [110] → [11$\text{1}$] → [00$\text{1}$] scans. These features correspond well with the structural characteristics of GaAs and Ge crystals. A discussion of the applicability of XPS angular distribution measurements to the geometric analysis of crystal surfaces is presented.     

Tumor promoters exist in two conformational states in solution. st]Stereochemistry of (3)-indolactam-V.

¹H-Nmr study and force field calculation of conformational Isomerism in (±)-indolactam-V which is a biologically active fragment of tumor promoter, teleocidin B, are described.     

Three tree-paths

Itai and Rodeh [3] have proved that for any 2-connected graph G and any vertex s ∈ G there are two spanning trees such that the paths from any other vertex to s on the trees are disjoint. In this paper the result is generalized to 3-connected graphs.     

Neon Color Spreading Promoted by Motion Information

We conducted experiments to investigate the effects of head-motion and object-motion to produce a perception of neon color spreading. Our experimental results indicated that a two-dimensional motion of yellow patches promoted the color spreading. A horizontal head-motion with motion parallax and three-dimensional pictorial depth information together with changing the viewing point stimulated the color spreading even, more than the two-dimensional motion. Thus, motion signals appear to offer useful information for the formation of a subjective contour and/or to activate the filling-in effect needed to generate neon color spreading. We also tested whether there was a difference between the effects of vertical and horizontal motion parallaxes for neon color spreading and found that there was none. This suggests that vertical head motion provides information in depth and surface perception equivalent to horizontal head motion.