Effect of mass recovery evaporator temperature and condenser temperature on the performance of a solar adsorption-based desalination plant

Water scarcity increases alarmingly as the population increases. Over the years, a number of salt water desalination techniques have been proposed and reached limitations. The requirement of minimum energy is very well satisfied by an adsorption system, since it can operate with low-grade energy and waste heat exhaust from most industries. The first part of this work discusses the effect of condenser and evaporator temperatures on the performance of silica-gel adsorption cycle mathematically. The second part discusses the performance variations due to mass recovery in the two-bed adsorption system mathematically. It was found that the reduction in condenser temperature and increase in the evaporator temperature both increase the fresh water productivity and cooling capacity of a plant. A desalination plant with mass recovery assistance is superior in performance than the conventional plant. Portable water productivity of 8?m³/day/ton is achieved with the condenser temperature of 15°C and the evaporator temperature of 30°C.     

Overview of the scientific production in the Pharmacy area in Brazil: profile and productivity of researchers granted with fellowships by the National Council for Scientific and Technological Development

In Brazil, the National Council for Scientific and Technological Development (CNPq) distributes productivity fellowships in research (RS) as a recognition to individuals with outstanding productivity levels in their areas. The aim of this study is to evaluate the scientific production of the Brazilian Pharmacy area, one division of the Health Sciences Great Area of CNPq, considering the profile and productivity levels of RS fellows. The results showed that most of the 156 active RS fellows in 2015 were female, with doctorate completed in the Southeast region (mainly in University of São Paulo) and with research activities developed in the South and Southeast regions. Most of their work was published in journals classified as B1 and B2 Qualis in Pharmacy by the Coordination for the Improvement of Higher Education Personnel (CAPES), with high prevalence of publications in local journals and/or specialized on medicinal plants. Besides, they featured much dependence on advising and productivity indexes related to the category and level of RS fellowship. The evolution of such data must be continually evaluated to determine the influence of CNPq productivity fellowships on performance and stratification of researchers in the Pharmacy area in Brazil.     

Electrocoagulation of methylene blue and eosin yellowish using mild steel electrodes

The paper presents the study of electrocoagulation (EC) of aqueous dye solutions of two different industrial dyes in a batch stirred cell. Experiments were carried out with 200 mg/l individual concentration of methylene blue (MB) and eosin yellowish (EY) in presence of NaCl as electrolyte. Effect of operating time and current density on the decolorization of dye solutions, reduction of chemical oxygen demand (COD) and variation in conductivity, pH during treatment has been studied. Small difference between color diminution and COD reduction has been found with the progress of treatment. First-order rate equation for dye removal has been developed from the experimental results. Sludge formation during EC and problems associated with this solid waste generation and disposal has been assessed. Energy consumption in KWh/m(3) with reduction of COD (kg) during treatment has been reported. Electric power consumption of 1.5 KWh reduces 0.21 and 0.11 kg COD from 0.24 and 0.14 kg of initial COD for MB and EY, respectively, starting from 200 mg/l dye concentration.     

Multi‐bit Boolean model for chemotactic drift of Escherichia coli

Dynamic biological systems can be modelled to an equivalent modular structure using Boolean networks (BNs) due to their simple construction and relative ease of integration. The chemotaxis network of the bacterium Escherichia coli (E. coli ) is one of the most investigated biological systems. In this study, the authors developed a multi‐bit Boolean approach to model the drifting behaviour of the E. coli chemotaxis system. Their approach, which is slightly different than the conventional BNs, is designed to provide finer resolution to mimic high‐level functional behaviour. Using this approach, they simulated the transient and steady‐state responses of the chemoreceptor sensory module. Furthermore, they estimated the drift velocity under conditions of the exponential nutrient gradient. Their predictions on chemotactic drifting are in good agreement with the experimental measurements under similar input conditions. Taken together, by simulating chemotactic drifting, they propose that multi‐bit Boolean methodology can be used for modelling complex biological networks. Application of the method towards designing bio‐inspired systems such as nano‐bots is discussed.Inspec keywords: cell motility, microorganisms, Boolean functionsOther keywords: multibit Boolean approach, conventional BNs, high‐level functional behaviour, steady‐state responses, chemoreceptor sensory module, drift velocity, chemotactic drifting, multibit Boolean methodology, complex biological networks, bio‐inspired systems, multibit Boolean model, chemotactic drift, dynamic biological systems, equivalent modular structure, Boolean networks, simple construction, chemotaxis network, bacterium Escherichia coli, biological systems     

Alkylation of phenol with tert‐butyl alcohol over a catalyst synthesized from coal fly ash

The alkylation of phenol with tert‐butyl alcohol was carried out in a continuous flow reactor over a catalyst synthesized from fly ash. The activity of the synthesized catalyst was compared with those of other conventional zeolite catalysts such as 13X (NaX) and Hβ. Of all the catalysts tested, zeolite Hβ showed the highest activity in phenol conversion followed by the synthesized zeolite (HZOP‐31). The activity of commercial 13X zeolite was found to be same as that of HZOP‐31. Ce‐exchanged catalyst (CeZOP‐31) showed even better performance than 13X in the alkylation of phenol. The effects of different parameters such as reactant mole ratio, temperature and space velocity on phenol conversion and tert‐butyl phenol selectivity were studied. The effect of mass transfer resistance was found to be negligible within the feed rate range and particle size range studied. The apparent activation energy for the reaction of tert‐butyl alcohol over HZOP‐31 was determined as 30.1 kJ mol^?1. Copyright © 2006 Society of Chemical Industry     

Electrical properties of Ta/sub 2/O/sub 5/ gate dielectric on strained-Si

High dielectric constant (high-k) thin Ta/sub 2/O/sub 5/ films have been deposited on tensilely strained silicon (strained-Si) layers using a microwave plasma enhanced chemical vapour deposition technique at a low temperature. The deposited Ta/sub 2/O/sub 5/ films show good electrical properties as gate dielectrics and are suitable for microelectronic applications. The feasibility of integration of strained-Si and high-k dielectrics has been demonstrated.     

Generation of solar spicules and subsequent atmospheric heating

Science China Technological Sciences -     

Growth,structural, thermal,optical, and electrical properties of potassium succinate–succinic acid crystal

Potassium succinate–succinic acid (KSSA), semi-organic single crystals were grown by slow evaporation growth technique using water solvent. Single crystal X-ray diffraction study revealed that the KSSA crystal belongs to monoclinic system. FT-IR and FT-Raman spectral studies were performed to identify the vibrations of functional groups. TGA/DTA analyses were carried out to characterize the melting behavior and stability of the title compound. The UV–Vis–NIR spectrum showed that the grown crystal is transparent in the entire visible region. Fluorescence studies were carried out in the range of 200–700 nm. The optical nonlinearity of KSSA was investigated at 532 nm using 7 ns laser pulses, employing the open aperture Z-scan technique. The photoconductivity study was carried out to know the conducting nature of the crystal. The laser damage threshold was measured using Q-switched Nd:YAG laser (1064 nm). Electrical properties of the crystal are studied using Hall Effect measurement.     

Effect of stabilizer on structural, optical and electrochemical properties of sol–gel derived spin coated TiO2 films

Thin films of TiO₂ were prepared using two different sol–gel routes. The two routes employed diethanolamine (DEA) and acetylacetone as stabilizing agents with titanium isopropoxide (Ti(OPrⁱ)₄) in ethanol as the deposition solution. The densification at 500 °C achieved the nanophase TiO₂ films, which were investigated by performing structural, optical and electrochemical studies. Ion storage capacity and transmission measurements showed superior response of the films derived from DEA. Between the films obtained from the two routes, the appearance of the rutile phase at lower temperature for the film synthesized using DEA was predicted on the basis of the thermal analysis of the corresponding xerogel. The nanocrystalline nature of the films was evident from the X-ray diffraction, atomic force microscopy, and scanning electron microscopy. The films deposited from both the stabilizers exhibited electrochromism in 1 M LiClO₄-propylene carbonate electrolyte on cathodic polarization.