Attractor Solutions in f(T) Cosmology

In this paper, we explore the cosmological implications of interacting dark energy model in a torsion based gravity namely $f(T)$. Assuming dark energy interacts with dark matter and radiation components, we examine the stability of this model by choosing different forms of interaction terms. We consider three different forms of dark energy: cosmological constant, quintessence and phantom energy. We then obtain several attractor solutions for each dark energy model interacting with other components. This model successfully explains the coincidence problem via the interacting dark energy scenario.Comment: 10 pages, 23 figures, version accepted for publication in European Physical Journal C (2012

Forward osmosis for the treatment of reverse osmosis concentrate from water reclamation : process performance and fouling control

University of Technology, Sydney. Faculty of Engineering and Information Technology.Reverse osmosis concentrate (ROC) is considered to be an obstacle in the production of high quality water from water reclamation and desalination plants using dense membrane systems. It normally comprises 10-30% of the feed water of water reclamation plants and 50-75% of the feed water from sea water desalination plants. While coastal water reclamation plants have the opportunity to discharge the RO concentrate directly into the ocean, inland facilities depend on controversial options such as surface water discharge, evaporation ponds, deep well injection and land applications. However, all these options are not sustainable or environmentally friendly. Therefore methods for proper disposal of RO concentrate especially for inland plants are urgently required. Various integrated concentrate treatment concepts have been proposed to minimise waste and maximise water recovery. A key issue in applying the Zero Liquid Discharge principle is the impact of foulants on the concentrate desalinating system, consisting of forward osmosis (FO) and a subsequent crystalliser. This study investigates forward osmosis, which appears to be a promising technology that represents a step towards zero liquid discharge. Organic fouling and inorganic scaling are hypothesised to be the main membrane foulants in FO. Furthermore FO is analysed in the context of removing organic micropollutants from RO concentrate. The following methodology was applied to this study. Two types of flat sheet membranes Cellulose Tricacetate (CTA) and Thin-Film Composite polyamide (TFC-PA) supplied by Hydration Technology Innovation for FO were used. Two model foulants - alginate and humic acid - were used to examine organic fouling of FO membrane. Real RO concentrate from the Sydney Olympic Park Authority’s water recycling plant was used to study fouling and its impact on water flux. Both membranes showed similar trends but permeate flux was higher with the TFC-PA membrane compared to the CTA-NW membrane. Forward osmosis was studied in two ways: FO mode (active layer facing feed solution); and pressure retarded mode (PRO) modes (support layer facing feed solution). The results indicate that alginate is a strong foulant of the PA membrane in PRO mode, and the resulting flux decreased sharply. On the other hand, however, in FO mode only moderate fouling was observed. CTA and TFC (PA) membranes were checked for fouling by humic acid. Approximately 7% TOC was adsorbed on the membrane’s surface resulting in a minor flux decline of 2-4%. Real RO concentrate was tested in concentrations of 38 mg/L (TOC equivalent) with both membranes in FO mode. The TOC adsorption at the membrane surface was low between 2-9%, however a high flux decline was observed with increasing draw solution concentrations. The observed flux decline was about 10-26% for the CTA membrane and 5-55% for the TFC-PA membrane, depending on the DS concentration of 1-4 M NaCl in both cases. Analysis of the inorganics revealed that inorganic scalants were the major contributor to the flux decline. Phosphates, carbonates and silicates were detected as the main scaling compounds. Reducing the pH meant that membrane scaling was significantly reduced. Organic micropollutants were not fully retained by the FO membrane. Size exclusion was identified as the main retaining process. In a comparison of the two membrane types, CTA removed the trace organics to a smaller degree than the TFC membrane. Removal ratio ranged from 40 to 97% (CTA) and 70 to 99% (TFC). Rejection depended on the DS concentration with increasing retention at higher fluxes. The study showed that forward osmosis is a promising technology for RO concentrate treatment and opens new avenues for further research work: • Recovery of nutrients and salts from RO concentrates in water reclamation • Recovery of draw solution and its reuse, thus making FO operation continuous • Post-treatment of permeate to produce high quality recycled wate

Solvable K-essence Cosmologies and Modified Chaplygin Gas Unified Models of Dark Energy and Dark Matter

This paper is devoted to the investigation of modified Chaplygin gas model in the context of solvable k-essence cosmologies. For this purpose, we construct equations of state parameter of this model for some particular values of the parameter $n$. The graphical behavior of these equations are also discussed by using power law form of potential. The relationship between k-essence and modified Chaplygin gas model shows viable results in the dark energy scenario. We conclude that the universe behaves as a cosmological constant, quintessence phase or phantom phase depending upon $n$.Comment: 14 pages, 6 figure

Pemahaman Teks Tentang Perempuan dalam Islam

In the scope of Islamic Studies, woman's matter has almost become controversy. One side considers woman as a second class. The other side considers as equal as man. Are three topics to be discussed in this article, namely the creating of woman, woman political role, and woman withes value? This article is intended to present philosophers different thought of woman. Through deep research, it is found that controversy occurred based on different understanding toward the religious text. One side comprehends the text in textual, the other side comprehends the text in contextual, without neglecting sociological and historical approaches of the emerging text.ملخص: وفىمجال البحث للتعـاليم الاسلأمـية، مازالـت المرأة موضوعة مشكـة عـن المـفـكـريـن. بعـضهـم يعـدونهاانـسـانا جانبيا، وبـعـضهم يك فحون المساواة بيـن الرجل والمرأة. وفىهذه المقالـة تـبحـث ثلاثمـسا ئل، وهى: اول تكويـن المرأة ودورالمرأة فىميدان السـياســة وقـيـم شـهادةالمرأة. وبعدالبحـث عـن هذهالمـسـألة بحـثـا عـميـقا، فـتـوجدالواقعة ان جذرالمـشـكـة هواخـتلأف الفهـم عـن النـصوالديـنـيـة. كان الفـريـق يـفهـمها فـهـمالفظيـا والـفـريـق الأ خريفهمها فهماسـياقـيا واطاريا بـتـقـرن الاجـتـماعـيـة والتاريخـيـة علىالنصواردة

Branching Ratio and CP-asymmetry for B-> 1^{1}P_{1}gamma decays

We calculate the branching ratios for B_{d}^{0}->(b_{1},h_{1})gamma at next-to-leading order (NLO) of alpha_{s} where b_{1} and h_{1} are the corresponding radially excited axial vector mesons of rho and omega respectively. Using the SU(3)symmetry for the form factor, the branching ratio for B_{d}^{0}->(b_{1},h_{1})gamma is expressed in terms of the branching ratio of the B_{d}^{0}-> K_{1}gamma and it is found to be B(B_{d}^{0}->b_{1}gamma)=0.71* 10^{-6} and B(B_{d}^{0}-> h_{1}gamma) =0.74*10^{-6}. We also calculate direct CP asymmetry for these decays and find, in confirmity with the observations made in the literature, that the hard spectator contributions significantely reduces the asymmetry arising from the vertex corrections alone. The value of CP-asymmetry is 10% and is negative like rho and omega in the Standard Model.Comment: 10 pages, 2 figure

Dynamics of interacting phantom and quintessence dark energies

We present models, in which phantom energy interacts with two different types of dark energies including variable modified Chaplygin gas (VMCG) and new modified Chaplygin gas (NMCG). We then construct potentials for these cases. It has been shown that the potential of the phantom field decreases from a higher value with the evolution of the Universe.Comment: 7 pages, 6 figures, accepted for publication in Astrophysics and Space Scienc

On the resolution of cosmic coincidence problem and phantom crossing with triple interacting fluids

We here investigate a cosmological model in which three fluids interact with each other involving certain coupling parameters and energy exchange rates. The motivation of the problem stems from the puzzling `triple coincidence problem' which naively asks why the cosmic energy densities of matter, radiation and dark energy are almost of the same order of magnitude at the present time. In our model, we determine the conditions under triple interacting fluids will cross the phantom divide.Comment: 22 pages, 6 figures, to appear in Eur. Phys. J. C (2009