卷烟信息网络防伪系统的构建及应用

介绍了卷烟信息网络防伪管理系统构建原理、技术特点和功能 ,及其在烟草行业中的应用。     

Functionalized oligopolysiloxanes by heterogeneously catalyzed equilibration polymerization reactions

Summary A new general procedure for preparation of functionalized oligopolysiloxanes of predetermined molecular weight is described. It utilizes heterogeneously catalyzed siloxane equilibration polymerization reactions which do not require troublesome and sometimes difficult post-preparative work-up procedures usually encountered with the well known homogeneously catalyzed corresponding reactions. The method is described using as example the preparation of , -telechelic vinyldimethylsiloxy-oligopolydimethylsiloxanes from octamethylcyclotetrasiloxane and 1,3-divinyltetramethyldisiloxane, but reference to the preparations of trimethylsiloxy-, dimethylsiloxy-and carboxypropyldimethylsiloxyoligopolydimethylsiloxanes, oligopolymethylhydridosiloxanes or their copolymers is also made.     

Morphometric and some immunohistochemical characteristics of human choroids plexus stroma and psammoma bodies

Psammoma bodies (PBs) are one of many choroids plexus aging changes. The aim of our research was to perform the quantification of PBs' presence in human choroids plexus stroma, as well as to evaluate the characteristics of choroids plexus stroma in cases in which PBs were present. Afterwards, the observations of the histochemical analysis would be confirmed by immunohistochemical analysis. Choroid plexuses of 30 cadavers were used for the histochemical and, choroids plexuses of 15 cadavers in which PBs' presence was confirmed during the histochemical analysis, were used as material for the immunohistochemical analysis. Light microscopy, histochemical, immunohistochemical, and morphometric method were applied during the study. Classification of the cases was performed by cluster analysis. We observed increase of choroids plexus PBs' presence during the aging process. But this increase is not linear. Their presence is the largest in the second cluster that is younger than the third and older than the first. Nuclear morphometric parameters of the stroma in these cases showed that the cellular composition in this cluster is different than in other two and, that contain larger number of lymphoid cells. Immunohistochemical analysis showed PBs' positive reaction on vimentin, CD45R0, and LCA markers, while in their vicinity, as well as inside them, numerous T-cells were observed. So, the presence of CD45R0 and LCA-positive T cells, PBs' positive reaction on the same markers, indirectly connect these cells with PBs' formation process.     

Synthesis and Theoretical Study of New Guanylated Cyclophosphazenes and Their Use in the CO2 Fixation into Styrene Carbonate

Three new guanylated cyclophosphazenes G1–G3 have been synthesized through the catalytic guanylation of three different bi, tetra and hexa (p-aminophenoxy)-cyclophosphazenes by using N,N’-diisopropylcarbodiimide as guanylating agent, ZnEt₂ as catalyst and dry tetrahydrofuran as solvent. The resulting products have been characterized by ¹H, ¹³C{¹H} and ³¹P{¹H} NMR spectroscopy. The hexaguanylated cyclophosphazenes exhibit a deep purple colour, unusual for this type of compounds. The electronic structure of these compounds was investigated by carrying out density functional calculations at PBE-D3(BJ)/TZP level of theory. The molecular structural analysis reveals that aromatic rings are stacked and time dependent density functional calculations show that a charge transfer electronic transition occurs between the aromatic rings which absorb light around 500–700 nm. Finally, the catalytic usefulness of guanylated cyclophosphazene compounds G1–G3 has been proven by the preparation of styrene carbonate from the reaction between styrene oxide and carbon dioxide.

     

Catalytic effects of metals of the iron subgroup on the chlorination of titanium carbide to form nanostructural carbon

The effect of the reaction temperature and the metals of an iron subgroup on the thermo-chemical treatment of titanium carbide with a chlorine gas and their influence on the carbon structure obtained thereby was studied. Different analytical methods such as porosity measurements, X-ray diffraction spectrometry and a high-resolution electron microscopy revealed the catalytic behaviour of the above-mentioned metals, which appeared to support the formation of graphitised carbon at much lower temperatures compared to those needed for the ordinary thermo-chemical chlorination of titanium carbide.     

Temperature effects on the removal of potential HFC replacements, CF3CH2CH2OH and CF3(CH2)2CH2OH, initiated by OH radicals

The gas-phase kinetic coefficients of OH radicals with two primary fluorinated alcohols, CF(3)CH(2)CH(2)OH (k(1)) and CF(3)(CH(2))(2)CH(2)OH (k(2)), potential replacements of hydrofluorocarbons (HFCs), are reported here as a function of temperature (T = 263-358 K) for the first time. k(1) and k(2) (together referred as k(i)) were measured under pseudo-first-order conditions with respect to the initial OH concentration using the pulsed laser photolysis/laser induced fluorescence technique. The observed temperature dependence of k(i) (in cm(3) molecule(-1) s(-1)) is described by the following Arrhenius expressions: k(1)(T) = (2.82 ± 1.28) × 10(-12) exp{-(302 ± 139)/T} cm(3) molecule(-1) s(-1) and k(2)(T) = (1.20 ± 0.73) × 10(-11) exp{-(425 ± 188)/T} cm(3) molecule(-1) s(-1).The uncertainties in the Arrhenius parameters are at a 95% confidence level (± 2σ). Uncertainties in k(i)(T) include both statistical and systematic errors. Activation energies were (2.5 ± 1.2) kJ/mol and (3.6 ± 1.6) kJ/mol for the OH-reaction with CF(3)CH(2)CH(2)OH and CF(3)(CH(2))(2)CH(2)OH, respectively. The global lifetime (τ) at 275 K for CF(3)CH(2)CH(2)OH and CF(3)(CH(2))(2)CH(2)OH due to the OH-reaction was estimated to be ca. 2 weeks and 5 days, respectively. The reported Arrhenius parameters can be used in 3D models that take into account the geographical region and season of emissions for estimating a matrix of instantaneous lifetimes. As a consequence of the substitution of the -CH(3) group by a -CH(2)OH group in HFCs, such as CF(3)CH(2)CH(3) and CF(3)(CH(2))(2)CH(3), the tropospheric lifetime with respect to the OH reaction is significantly shorter and, since their radiative forcing is similar, global warming potentials of CF(3)CH(2)CH(2)OH and CF(3)(CH(2))(2)CH(2)OH are negligible. Therefore, CF(3)CH(2)CH(2)OH and CF(3)(CH(2))(2)CH(2)OH seem to be suitable alternatives to HFCs.     

Synthesis,characterization and compared reactivity of asymmetrical ansa-metallocenes

Rac and meso ansa-zirconocenes [Zr{1-Me₂Si(3-R-(η⁵-C₉H₅))(3-R′-(η⁵-C₉H₅))}Cl₂] (R = Et, R′ = H; R = Pr, R′ = H; and R = Et, R′ = Pr) 4–9 have been prepared by the reaction of ZrCl₄ with the corresponding dilithiated derivatives from the ligands {1-Me₂Si(3-R-(η⁵-C₉H₅))(3-R′-(η⁵-C₉H₅))} (R = Et, R′ = H 1; R = Pr, R′ = H 2; and R = Et, R′ = Pr 3) in diethyl ether/toluene at ?78 °C. The molecular structure of rac [Zr{1-Me₂Si(3-Et-(η⁵-C₉H₅))(3-Pr-(η⁵-C₉H₅))}Cl₂] 8 has been determined by single crystal X-ray diffraction studies, which show a pseudotetrahedral environment formed by the two chlorine ligands and two η⁵-coordinated indenyl ligands. The activity in homogeneous and heterogeneous polymerization is compared and discussed.     

Tibetan Sentiment Classification Method Based on Semi-Supervised Recursive Autoencoders

We apply the semi-supervised recursive autoencoders (RAE) model for the sentiment classification task of Tibetan short text, and we obtain a better classification effect. The input of the semi-supervised RAE model is the word vector. We crawled a large amount of Tibetan text from the Internet, got Tibetan word vectors by using Word2vec, and verified its validity through simple experiments. The values of parameter α and word vector dimension are important to the model effect. The experiment results indicate that when α is 0.3 and the word vector dimension is 60, the model works best. Our experiment also shows the effectiveness of the semi-supervised RAE model for Tibetan sentiment classification task and suggests the validity of the Tibetan word vectors we trained.