Comparative numerical study of single and two-phase models of nanofluid heat transfer in wavy channel

The main purpose of this study is to survey numerically comparison of two- phase and single phase of heat transfer and flow field of copper-water nanofluid in a wavy channel. The computational fluid dynamics （CFD） prediction is used for heat transfer and flow prediction of the single phase and three different two-phase models （mixture, volume of fluid （VOF）, and Eulerian）. The heat transfer coefficient, temperature, and velocity distributions are investigated. The results show that the differences between the temperature fie].d in the single phase and two-phase models are greater than those in the hydrodynamic tleld. Also, it is found that the heat transfer coefficient predicted by the single phase model is enhanced by increasing the volume fraction of nanoparticles for all Reynolds numbers; while for the two-phase models, when the Reynolds number is low, increasing the volume fraction of nanoparticles will enhance the heat transfer coefficient in the front and the middle of the wavy channel, but gradually decrease along the wavy channel.

Controversies over fair value accounting： The case of SMEs

This study analyses IASB＇s stipulations on fair value usage in its standard designed for SMEs and the reactions of national standard setters, preparers and users of financial reporting in this respect. It tries to clarify fair value applications such as market value and value in use and the appropriateness of their usage for the case on hand. This research determines the inconsistencies within IASB ED IFRSfor SMEs （2007） related to the usage of fair value, underlined by the respondents＇ comment letters. The content analysis of all the above, conducted according to the type of economy and nature of respondent, along with the statistical techniques applied, indicates a partial approval of fair value usage under the following conditions： clarification of the concept, details on its usage in relation to market liquidity and the nature of the asset, additional guidance regarding the measurement methods. We advocate for the value in use, an application of the fair value based on internal valuations, which offers an adequate cost-benefit rate. The final version ofIFRSfor SMEs highlights both the preference of market information over the internal valuations and the insufficient information regarding solutions suited for non-liquid markets. It may be appropriate for the IASB, maybe in collaboration with the IVSC, to provide guidance and details regarding the implementation and disclosure of the valuation techniques applicable to this type of entities.

二氧化钛气凝胶基质中金纳米粒子的光催化活性和结构(英文)

TiO2 -Au aerogels containing different amounts of gold nanoparticles of different sizes (5 and 16 nm) were successfully synthesized using a sol-gel procedure, and were tested for salicylic acid photodegradation under UV irradiation. The structure and morphology of the obtained materials were investigated using X-ray diffraction, transmission electron microscopy, and N2 adsorption-desorption measurements. UV-Vis spectroscopy was used to study the optical properties. The effects of the gold nanoparticles on the TiO2 crystallization process were twofold, as follows: (i) the number of crystallized zones was strongly related to the concentration of the gold nanoparticles, and (ii) the smaller gold particles increased the time taken for the crystallization of the samples. It was found that the noble metal-doped samples exhibited higher degradation rates compared with bare titania. It was found that the most active photocatalyst in each studied system was the sample with the highest concentration of gold nanoparticles. Additionally, the highest degradation rate value was obtained with the smallest Au nanoparticles (46.4 10-3 μmol/(L·s).

Technology Makes it Happen -But it Doesn＇t Tell the Story by Itself

Technology we used in order to tell visual stories is constantly improving, newer technology superseding the old one at a breathtaking rate. Yet, video technology is a means and does not do the storytelling itself. However, visual storytellers must keep themselves updated with technology in order to get the best of their work. DSLR cameras are now leading the visual storytelling pack and some respected visual storytellers share conclusions of their experiences.

Cognitive coping strategies, emotional distress and quality of life in mothers of children with ASD and ADHD—A comparative study in a Romanian population sample

The Quality of Life (QoL) represents a dimension of the overall status and of the wellbeing that might be influenced by various factors. Mothers’ emotional and behavioral reactions, when having a child with diagnosis of mental disorder, are different depending on the emotional distress and cognitive coping strategies used. The aim of this study was to assess the cognitive coping strategies, emotional distress and the relationship between them and the quality of life in mothers of children with Autism Spectrum Disorder (ASD) compared to mothers of children with Attention Deficit Hyperactive Disorder (ADHD). Data were collected from 114 mothers of children with diagnosis of ASD or ADHD. Different psychological measurements have been used in order to assess the quality of life (Family Quality of Life Survey) cognitive coping strategies (Cognitive-Emotional Regulation Questionnaire) and emotional distress (Profile of Affective Distress) of the parents. For QOL and emotional distress, we didn’t find significant differences between the two groups. The coping strategies of the mothers of children with ASD that significantly correlated with the overall assessment of the family quality were: positive refocusing, positive reevaluation and catastrophizing. The results suggest that the use of adaptive coping strategies correlates with a higher family quality of life, while for the maladaptive ones, the relationship is reversed.

Effect of different surface treatments on bioactivity of porous titanium implants

The work aims to characterize the structure and to evaluate in vitro the effect of different surface treatments on the bioactivity of medical grade Ti6Al7 Nb alloy implants manufactured by selective laser melting. In order to improve the bioactivity of these samples, they were subjected to heat treatment,chemical treatment, and impregnation with bioactive materials. To evaluate the apatite forming ability, the samples were immersed in simulated body fluid solution) and characterized before and after immersion by scanning electron microscopy, X-ray diffraction and X-ray photoelectron spectroscopy.The composition and the texture of the surfaces after the applied treatments have a selective effect on apatite layer development on the surface of samples.

MATHEMATICAL MODELING OF CELL DYNAMICS AFTER ALLOGENEIC BONE MARROW TRANSPLANTATION

In this paper a basic mathematical model is introduced to describe the dynamics of three ceil lines after allogeneic stem cell transplantation： normal host cells, leukemic host cells and donor cells. Their evolution is one of competitive type and depends upon kinetic and cell-cell interaction parameters. Numerical simulations prove that the evolution can ultimately lead either to the normal hematopoietic state achieved by the expansion of the donor cells and the elimination of the host cells, or to the leukemic hematopoietic state characterized by the proliferation of the cancer line and the suppression of the other cell lines. One state or the other is reached depending on cell-cell interactions （anti-host, anti-leukemia and anti-graft effects） and initial cell concentrations at transplantation.The model also provides a theoretical basis for the control of post-transplant evolution aimed at the achievement of normal hematopoiesis.