The Photopolymerization Kinetics of Acryl amide Sensitized with Toluidine Blue-Alcoholamine Induced by He-Ne Laser

Toluidine blue(TB) is a good sensitizer for the polymerization of acrylnmide(AM) induced by He-Ne laser. With TB as a sensitizer and various alcoholamine as donors, the photoredox of TB and the polymerization kinetics of AM induced by He-Ne laser were investigated. It was found that either for the photoredox of TB or for the polymerization of AM, the activity of alcoholamine increases in the order of EOA相似文献   

Two novel dicoumaro-p-menthanes from Gerbera piloselloides (L.) CASS

Two new type dicoumarins (dicoumaro-p-menthanes), named dibothrioclinins I (1) and II (2) were isolated from the roots and rhizomes of Gerbera piloselloides (L.) CASS., collected in Yunnan Province, China. Their structures were elucidated on the basis of MS, 1D ((1)H-NMR, (13)C-NMR, DEPT and NOE) and 2D ((1)H-(1)H COSY, HMQC, HMBC) NMR spectral analyses. The relative structures of the two compounds were established by NOE difference spectroscopy and further confirmed by single-crystal X-ray diffraction studies.     

Synthesis, Characterization and Crystal Structure of a One-dimensional Diamagnetic Metal-radical Complex: [Zn(NIT4py)2(DTB)2(H2O)2]

A novel one-dimensional complex [Zn(NIT4py)₂(DTB)₂(H₂O)₂] (1), with mixed ligands [where NIT4py is 2-(4′-pyridyl)-4,4,5,5-tetramethylimidazoline-1-oxyl-3-oxide and DTB is 3,5-dinitrobenzoate] has been synthesized and characterized by elemental analyses, i.r., u.v.–vis spectra, thermogravimetric analysis, X-ray single crystal diffraction and magnetic measurements. The complex crystallizes in the triclinic crystal system and space group Pî. The Zn ^II ion is in a distorted octahedral environment: two nitrogen atoms from two NIT4py entities, two oxygen atoms from two DTB units in the basal plane; and two oxygen atoms from the two water molecules in the axial position. The [Zn(NIT4py)₂(DTB)₂(H₂O)₂] units are connected as a one dimension chain by the intermolecular hydrogen bonds. The complex exhibits intramolecular antiferromagnetic interactions between the two radicals.     

Dispersion state of CuO on CeO2

XRD and XPS are used to study the dispersion state of CuO on ceria surface. The dispersion capacity values of CuO measured by the two methods are consistent, which are of 1.20 mmol CuO/100 m² CeO₂. In addition, the results reveal that highly dispersed Cu²⁺ ions are formed at low CuO loadings and that increasing the CuO content to a value higher than its dispersion capacity produces crystalline CuO after the surface vacant sites on CeO₂ are filled. The atomic composition of the outermost layer of the CuO/CeO₂ samples has been probed by using static secondary ion mass spectroscopy (SSIMS), and the ratim of Cu/Ce are found to be 0.93 and 0.46 for the 1.22 and 0.61 mmol CuO/CeO₂ samples respectively. Temperature-programmed reduction (TPR) profile with two reduction peaks at 156 and 165°C suggests that the reduction of highly dispersed Cu²⁺ ions consists of two steps and is easier than that of CuO crystallites, in which the TPR profile has only one reduction peak at about 249°C. The above experimental results are in good agreement with the prediction of the incorporation model. Project supported by the National Natural Science Foundation of China.     

Effect of some factors on the energy band structure of proteins

The effects of four factors (different side chains, side-chain disorder, conformational change, and ions and water) on the energy band structures of proteins have been investigated with the aid of the CNDO/2 crystal orbital method. The results indicate that these factors are very important. The consequences of these effects on the semiconductive properties of proteins are discussed.     

Reversible replication between ordered mesoporous silica and mesoporous carbon

Highly ordered mesoporous silica can be regenerated from a mesoporous carbon CMK-3 that is a negative replica of mesoporous silica SBA-15, indicating reversible replication between carbon and inorganic materials.     

Co-C bond dissociation energy and reaction volume change of 2',5'-dideoxyadenosylcobalamin studied by laser-induced time-resolved photoacoustic calorimetry

Time resolved photoacoustic calorimetry (PAC) was applied to a study of the photolysis of a coenzyme B(12) analog 2',5'-dideoxyadenosylcobalamin, which lacks an -OH group at the 2' position of ribofuranose ring. In aqueous solution, we report for the first time the quantum yield Phi(d) (0.25+/-0.02), Co-C bond dissociation energy (BDE; 31.8+/-2.5 kcal mol(-1)) and reaction volume change deltaV(R) (6.5+/-0.5 ml mol(-1)) due to conformation changes of the corrin ring and its side chains accompanying the cleavage of the Co-C bond. These values for the analog are very similar to those for the natural cofactor. Based our results and previous studies, a possible explanation for the similarity in their structure and properties versus the large difference in their enzymatic activity is discussed.     

二氢茉莉酮酸甲酯的简便合成方法

本文报道二氢茉莉酮酸甲酯的简便合成方法。先由丁二酸和庚酰氯反应得到2-戊基-1,3-环戊二酮(1),再用甲醇醚化1,可得到2-戊基-3-甲氧基-环戊-2-烯酮(2)。2与丙二酸二甲酯反应生成(2-戊基-3-酮-1-环戊烯-)基乙酸甲酮(3)。最后,催化氢化3,便可得到二氢茉莉酮酸甲酯(4)。