Novel Synthesis and Antimicrobial Activity of 7-Substituted Derivatives of 7-(methylthio)-5-oxo-2-phenyl-5H-[1,3,4]thiadiazolo[3,2-b]- pyrimidine-6-carbonitrile

2-Amino-5-phenyl-1,3,4-thiadiazole on reaction with ethyl-2-cyano-3,3-bis(methylthio)acrylate in the presence of N,N′-dimethyl formamide and catalytic amount of anhydrous potassium carbonate afforded 7-(methylthio)-5-oxo-2-phenyl-5H-[1,3,4]thiadiazolo[3,2-b]pyrimidine- 6-carbonitrile under similar experimental condition, compounds 7-(methylthio)-5-oxo-2-phenyl-5H-[1,3,4]thiadiazolo[3,2-b]pyrimidine-6-carbonitrile on treatment independently with aryl amines/ heteryl amines/phenols containing active methylene group yielded correspon-ding 7-substituted derivatives. All these newly synthesized compounds were screened for antimicrobial activity.

Nano-/microstructure improved photocatalytic activities of semiconductors

Photocatalysis has emerged as a promising technique owing to its valuable applications in environmental purification. With the demand of building effective photocatalyst materials, semiconductor investigation experienced a developing process from simple chemical modification to complicated morphology design. In this review, the general relationship between morphology structures and photocatalytic properties is mainly discussed. Various nano-/microsized structures from zero- to three-dimensional are discussed, and the photocatalytic efficiency correspon- ding to the structures is analysed. The results showed that simple structures can be easily obtained and can facilitate chemical modification, whereas one- or three-dimensional structures can provide structure-enhanced properties such as surface area increase, multiple reflections of UV light, etc. Those principles of structure-related photocatalytic properties will afford basic ideology in designing new photocatalytic materials with more effective catalytic properties.

Taalgebruik in Schoolboeken en Anderstaligen in het Voortgezet Onderwijs

Young immigrant adults may have difficulties in schools because of a lack of literate skills in the second language, viz. Dutch. If they are confronted with texts that are too difficult for them they may stagnate in their (literate) language development and even drop out of school. Teachers with and without experience in teaching Dutch as a sec-ond language ranked a number of fragments of Dutch school-books as to degree of difficulty. All teachers believed that only the lowest difficulty level was appropriate for all their pupils (Dutch and immigrant). They differed in their judgement as to the appropriateness of the subject matter of the texts. An analysis of the texts with respect to linguistic features led to the definition of three levels of difficulty, correspon-ding to the three first grades of the secondary school. On the whole the texts are for Dutch natives. Immigrant pupils probably use certain strategies to compensate for evident lack of text comprehension at the micro level of a text (word know-ledge, sentence structures etc.)