Highly efficient construction of chiral dispirocyclic oxindole/thiobutyrolactam/chromanone complexes through Michael/cyclization cascade reactions with a rosin-based squaramide catalyst

An efficient asymmetric Michael/cyclization cascade reaction of 4-chromanones with isothiocyanato oxindoles has been revealed. Under bifunctional organocatalysis by rosin-based squaramide catalyst, a series of spiro[oxindole/thiobutyrolactam/chromanone] complexes were conveniently constructed in a highly stereoselective manner (up to 99% yields, > 20:1 dr and >99% ee). The reaction leads to the formation of three contiguous stereogenic centers and two spiro quaternary stereocenters.     

Neighbor Sum Distinguishing Total Choice Number of Planar Graphs without 6-cycles

Pil?niak and Wo?niak put forward the concept of neighbor sum distinguishing (NSD) total coloring and conjectured that any graph with maximum degree Δ admits an NSD total (Δ+3)-coloring in 2015. In 2016, Qu et al. showed that the list version of the conjecture holds for any planar graph with Δ ≥ 13. In this paper, we prove that any planar graph with Δ ≥ 7 but without 6-cycles satisfies the list version of the conjecture.     

ALTERNATELY LINEARIZED IMPLICIT ITERATION METHODS FOR SOLVING QUADRATIC MATRIX EQUATIONS

A numerical solution of the quadratic matrix equations associated with a nonsingular M-matrix by using the alternately linearized implicit iteration method is considered. An iteration method for computing a nonsingular M-matrix solution of the quadratic matrix equations is developed, and its corresponding theory is given. Some numerical examples are provided to show the efficiency of the new method.     

纤维上染料的FT-Raman光谱法研究

本文采用近红外傅立叶变换拉曼光谱技术（NIR FT－Raman)对27种染色纤维样品进行了检验，同时得到了它们的本底纤维和染料的拉曼谱图，然后利用计算机谱图处理程序进行拉曼差谱处理，获得了染色纤维上染料的拉曼谱图，由此能够实现对纤维上染料的鉴定，根据染料分子的拉曼光谱的特征将24种染色纤维按局部结构特征分为7类，有助于同色纤维上染料的鉴别，该方法快速、简便，灵敏度高，不需从纤维上提取染料。     

Structure and Magnetic Properties of A μ‐Phenoxido‐bridged Dinuclear Cobalt(II) Complex

A new dinuclear cobalt(II) complex [Co₂L₂Cl₂(CH₃OH)₂] ( 1 ), where HL = 3‐[(furan‐2‐ylmethylimino)methyl]‐2‐hydroxy‐5‐methylbenzaldehyde, derived from the in situ condensation of 2,6‐diformyl‐4‐methylphenol with furfurylamine, was prepared and structurally and magnetically characterized. Single crystal X‐ray structural determination reveals that the structure consists of centrosymmetric dinuclear units with each Co^II ion in a slightly distorted octahedral environment. Lines’ model, which in principle can theoretically separate in spin‐only and orbital contribution, was used to fit the variable temperature susceptibility (2–300 K), suggesting an intramolecular antiferromagnetic interaction between the cobalt(II) ions.     

Studies on Biomlmetic Oxidation for the Model Compound of Cytochrome P-450(IV)——Studies on Oxygenation of Cyclohexane Catalyzed by μ-Oxo-bis(5,10, 15,20-tetraphenylporphinato)iron(Ⅲ)

Chloro-(5,10,15,20-tetraphenylporphinato)iron(Ⅲ)(TPPFeCl)(A) used as a model compound of cytochrome P-450 to catalyze the monooxyenation of alkane is known, but the oxygenation of alkane catalyzed by μ-oxo-bis(5,10,15,20-tetraphenylporphinato)-iron(Ⅲ)((TPPFe)_2O)(B) has not been reported. The catalytic characteristics of B for the oxygenation of cyclohexane with PhIO in CH_2Cl_2 and cyclohexane medium were studied. We found that B had a fairly good     

Synthesis of micro-sized titanium dioxide nanosheets wholly exposed with high-energy {001} and {100} facets

A new synthetic strategy was developed to prepare large-sized well-defined anatase TiO(2) nanosheets wholly dominated with thermodynamically unfavorable high-reactive {001} and {100} facets, which has a percentage of 98.7% and 1.3%, respectively. The as-prepared anatase TiO(2) nanosheets show a well-faceted morphology and have a large size in length (ca. 4.14 μm). The formation mechanism of the anatase TiO(2) nanosheets was also analyzed and investigated.     

α-[(1H-1,2,4-三唑-1-基)甲基]-β-芳基-β-芳硫基取代苯丙醇的合成及生物活性研究

利用1，3－二芳基－2－[（1H－1，2，4－三唑－1－基）甲基]－2－丙烯－1－酮7与取代硫酚进行1，4－亲核加成，经重排得到化合物4，将化合物4用NaBH4还原，得到目标化合物5，其结构经元素分析、^1H NMR和红外光谱所确证，并测试化合物5对小麦锈病的活性，结果发现大部分化合物的杀菌活性均较低。     

Self-repairing and superhydrophobic film of gold nanoparticles and fullerene pyridyl derivative based on the self-assembly approach

In this paper, we report that thin gold films can be prepared on the water/toluene interface by self-assembly of gold nanoparticles (NPs) and fullerene pyridyl derivatives. The assembled films were characterized using UV–vis spectroscopy and transmission electron microscope (TEM). The films show self-repairing and superhydrophobic properties.