A comparative study on preparation of TiO2 pellets as photocatalysts based on different precursors

The porous Ti0₂ pellets were prepared based on pigment grade titaina, P25 titania powder and titaniurn(lV) butoxide. The characterization was done with X-Ray diffraction, scanning electron microscopy and BET measurements. The result shows that Ti0₂ pellets by using titaniurn(IV) butoxide with some addictive have the best surface porosity, with specific surface area of 196.9m²/g. For pigment grade titania and P25 titania powder, it is still effective to enhance the surface area after reassembling. The surface area increased from 11.6 to 29.2 m²/g for pigment grade titania and from 50 to 84.4 m²/g for P25 titania powder. Furthermore, it has been investigated on how to optimize and get the highest surface area by controlling the sintering temperature, reaction temperature, pH of solution, and the amount of alcohol and addictive of surfactant during preparation. The experimental photocatalytic degradation of acetone and toluene was performed using titania pellets made from P25 titania powder.

Hematopoietic perturbation in zebrafish expressing a tel-jak2a fusion

Objective
Various TEL-JAK2 fusions have been identified in patients with lymphoblastic and myeloid leukemias that result in constitutive activation of the JAK2 kinase domain. Such fusions can mediate factor-independent growth of hematopoietic cell lines and induction of malignancy in mouse models.
Materials and methods
To assess whether zebrafish could be utilized as a suitable model for the study of myeloid oncogenesis, we generated a zebrafish tel-jak2a fusion oncoprotein based on that seen in a case of chronic myeloid leukemia. This was transiently expressed in zebrafish embryos under the control of the spi1 promoter, which is strongly active in myeloid precursors.
Results
Visual, histological, and molecular analysis revealed disruption of normal embryonic hematopoiesis, including perturbation of the myeloid and erythroid lineages.
Conclusion
These results indicate that the zebrafish tel-jak2a oncoprotein is functional, and suggest that this organism will be useful for the experimental study of myeloid malignancy.

Psychosocial precursors and correlates of differing internalizing trajectories from 3 to 15 years

Psychosocial precursors and correlates of parent-reported internalizing behavior trajectories across the age span of 3–15 years were explored using a community-based cohort of Australian children. Six internalizing trajectories had previously been identified for both girls (N = 810) and boys (N = 874) in this sample, comprising stable low, high, decreasing, and increasing pathways. Infancy and toddler temperamental traits (inhibition/shyness, irritability), behavior problems, and parent–child relationship difficulties constituted significant risks for subsequent problematic internalizing profiles. Several gender-specific trends were evident, with temperamental reactivity and shyness, less optimal parenting, and peer difficulties more salient for girls on increasing trajectories whereas externalizing problems were more prominent among boys on increasing trajectories. Factors associated with recovery from elevated symptoms included higher levels of social competence, better parent and peer relations, and more positive school adjustment. Findings suggest that individual characteristics and relationship experiences may be involved in the development and course of internalizing problems.

Longitudinal examination of physical and relational aggression as precursors to later problem behaviors in adolescents

Research has addressed the consequences of being a victim of physical and relational aggression but less so the consequences of being an aggressor during adolescence. Consequently, relatively little is known about the extent to which aggression in early adolescence increases the risk of later aggression and other psychosocial problems. This study involves a representative sample of seventh- and ninth-grade students from Washington State ( N = 1,942). Students were surveyed on recruitment and then again 1 and 2 years later to learn about ongoing behavior problems, substance use, depression, and self-harm behaviors. Surveys also included measures of several hypothesized promotive factors: attachment to family, school commitment, and academic achievement. Findings suggest that being physically and/or relationally aggressive in grades 7 to 9 increases the risk of aggression and possibly other problem behaviors after accounting for age, gender, race, and a prior measure of each outcome. Independent promotive effects were observed in most analyses, although family attachment appeared a less robust predictor overall. Implications for prevention include acting on the behavior itself and enhancing promotive influences to lessen the risk of agression and other related problems.

Superhydrophobic fabrics from hybrid silica sol-gel coatings: Structural effect of precursors on wettability and washing durability

Particle-containing silica sol was synthesized by co-hydrolysis and co-condensation of two silane precursors, tetraethylorthosilicate (TEOS) and an organic silane composed of a non-hydrolyzable functional group (e.g., alkyl, flourinated alkyl, and phenyl), and used to produce superhydrophobic coatings on fabrics. it has been revealed that the non-hydrolyzable functional groups in the organic silanes have a considerable influence on the fabric surface wettability. When the functional group was long chain alkyl (C16), phenyl, or flourinated alkyl (C8), the treated surfaces were highly superhydrophobic with a water contact angle (CA) greater than 170°, and the CA value was little affected by the fabric type. The washing durability of the superhydrophobic coating was improved by introducing the third silane containg epoxide group, 3-glycidoxypropyltrimethoxsilane (GPTMS), for synthesis. Although the presence of epoxide groups in the coating slightly reduced the fabrics' superhydrophobicity, the washing durability was considerably improved when polyester and cotton fabrics were used as substrates.

Precursors and correlates of anxiety trajectories from late childhood to late adolescence

The present research employed a prospective, multi-informant design to examine precursors and correlates of differing anxiety profiles from late childhood to late adolescence. The sample consisted of 626 boys and 667 girls who are participants in the Australian Temperament Project, a large, longitudinal, community-based study that has followed young people's psychosocial adjustment from infancy to adulthood. The present research analyzes data collected from the first 12 waves of data, from 4–8 months to 17 years. Parents, primary school teachers, maternal and child health nurses, and from the age of 11 onward, the young people themselves have provided survey data. Trajectory analyses revealed three distinct patterns of self-reported anxiety from late childhood to late adolescence, comprising low, moderate, and high (increasing) trajectories, which differed somewhat between boys and girls. A range of parent- and teacher-reported factors was found to be associated with these trajectories, including temperament style, behavior problems, social skills, parenting, negative family events, and peer relationships. Compared with male trajectories, female trajectories were associated with a greater variety of psychosocial variables (including parenting and externalizing problems), which may partially account for the higher prevalence of anxiety in adolescent girls compared with boys. Findings shed light on gender-specific pathways to anxiety and the need for comprehensive, integrative approaches to intervention and prevention programs.

The reactivity of N-heterocyclic carbenes and their precursors with [Ru3(CO)12]

The ambient temperature reaction of the N-heterocyclic carbenes (NHCs) 1,3-dimesitylimidazol-2-ylidene (IMes) and 1,3-bis(2,6-diisopropylphenyl)imidazol-2-ylidene (IDipp) with the triruthenium cluster [Ru3(CO)12], in a 3 : 1 stoichiometric ratio, results in homolytic cleavage of the cluster to quantitatively afford the complexes [Ru(CO)4(NHC)] (1; NHC = IMes, 2; NHC = IDipp). Reaction of the 2-thione or hydrochloride precursors to IMes, i.e. S[double bond, length as m-dash]IMes and IMes·HCl, with the same triruthenium cluster affords the complexes [Ru4(μ4-S)2(CO)9(IMes)2] (3) and [Ru4(μ4-S)(CO)10(IMes)2] (4) (3 : 1 and 2 : 1 reaction), and [{Ru(μ-Cl)(CO)2(IMes)}2] (7) (3 : 1 reaction) respectively. By contrast, the complex [Ru3(μ3-S)2(CO)7(IMeMe)2] (6), where IMeMe is 1,3,4,5-tetramethylimidazol-2-ylidene, is the sole product of the 2 : 1 stoichiometric reaction of S[double bond, length as m-dash]IMeMe with [Ru3(CO)12]. Compounds 1–4, 6 and 7 have been structurally characterised by single crystal X-ray diffraction.

Preparation of polyacrylonitrile–natural polymer composite precursors for carbon fiber using ionic liquid co solvent solutions

We report on the use of ionic liquid co-solvents in the preparation of polyacrylonitrile–natural polymer carbon fibers as low cost environmentally friendly alternatives to conventional carbon fibers precursors and processing solvents. We have characterized the structure properties of the new composites as a function of dissolving solvent using solid state NMR, DSC, FTIR and TGA. We show that the dissolving solvent plays a significant role in the properties of the new composites, we also find that the incorporation of the natural polymer additive impacts the thermal transition temperatures for the PAN

In situ synthesis of TiC-Fe composite overlays from low cost TiO 2 precursors using plasma transferred Arc deposition

A direct conversion of TiO2 into TiC during plasma transferred arc deposition is a cheap and novel approach to produce wear resistant coatings. The present study explored the use of a low cost titanium ore as precursor for titanium carbide in metal matrix composite overlays. The deposited layers were characterized using optical microscopy, scanning electron microscopy, x-ray diffraction and microhardness testing. A carbothermic reduction of the titanium oxides took place during the deposition of the coating by plasma transferred arc. The overlays produced in this way consisted of fine titanium carbides evenly dispersed in an iron matrix. The opportunities and limitations of this approach are discussed.