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1.
A simple transient performance of floating cum tilted-wick type solar still has been presented by incorporating the effects of water flowing over a glass cover, heat capacity of tilted-wick water surface and floating-wick water surface. Explicit expressions for flowing water, glass, tilted-wick water surface and floating-wick water surface temperature and efficiency of the system have been derived. Numerical calculations have been carried out for a typical day in the month of March 2004. The relative standard deviations between the numerical and experimental results of different temperature components of the proposed still have been found. The results indicate that the relative standard deviations between theoretical and experimental results are less than 8% (glass cover), 2% (tiltedwick water surface), 1% (floating-wick water surface) and 2% (flowing water at the lower end of the glass cover) an average for the working hours of the day. Moreover, based on the numerical results, the following conclusions have been drawn: (i) glass cover temperature decreases significantly; (ii) the effect of water flowing over the glass cover has a fascinating effect on the production of distillate output during peak sunny hours; (iii) water flow rate of 1.5 m/s is optimum, and beyond it the efficiency decreases. Experimental investigations have been performed at Sri Ramakrishna Mission Vidyalaya College of Arts and Science, Coimbatore, India. 相似文献
2.
An analytical expression for the thermal efficiency of evaporative heat loss and heat transfer for a open- and closed-cycle systems of floating tilted wick solar stills in terms of system design and climatic parameters has been derived. The expression for open- and closed-cycle systems was validated by performing experiments for both systems. Optimization of the design of the still for evaporative cooling (open cycle) and the distillation unit (closed cycle) was obtained using the derived analytical expression for large-scale installation. Numerical calculations were also carried out for a typical summer day at the Sri Ramakrishna Mission Vidyalaya College of Arts and Science, Coimbatore, India, to predict the performance of the still. 相似文献
3.
In this study, carboxymethyl sago pulp (CMSP) derived from sago waste was successfully crosslinked with ferric ions in the presence of chitosan forming a novel immobilization matrix for p-nitrophenol (PNP)-acclimated activated sludge. On the basis of the shortest biodegradation time of PNP, the optimized operational conditions of immobilization were found to be: 7 w/v% CMSP, 9 g L−1 of activated sludge, 0.1 M ferric ion, and 15 min of crosslinking time. Observable inhibited PNP biodegradation was exhibited by the suspended activated sludge at the initial PNP concentration of 400 mg L−1. In contrast, complete mineralization was achieved by the CMSP/chitosan-immobilized activated sludge (CMSP/Ch-AS) beads. The results revealed the important role of CMSP/Ch hydrogel in protecting activated sludge from the toxicity of PNP. The CMSP/Ch-AS beads could be reused consecutively up to three and two cycles, respectively, for the biodegradation of PNP at 200 and 400 mg L−1, with the attainment of more than 99% of PNP removal at each cycle. © 2019 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2019 , 136, 47531. 相似文献
4.
Dual crosslinked carboxymethyl sago pulp/pectin hydrogel beads as potential carrier for colon‐targeted drug delivery 下载免费PDF全文
Hui Li Tan Li Shan Tan Yeon Yin Wong Saravanan Muniyandy Kamaruddin Hashim Janarthanan Pushpamalar 《应用聚合物科学杂志》2016,133(19)
Carboxymethyl sago pulp (CMSP)/pectin hydrogel beads were synthesized by calcium crosslinking and further crosslinked by electron beam irradiation to form drug carrier for colon‐targeted drug. Sphere‐shaped CMSP/pectin 15%/5% hydrogel beads is able to stay intact for 24 h in swelling medium at pH 7.4. It shows pH‐sensitive behavior as the swelling degree increases as pH increases. Fourier transform infrared spectroscopy analysis confirmed the absence of chemical interaction between hydrogel beads and diclofenac sodium. Differential scanning calorimetric and X‐ray diffraction studies indicate the amorphous nature of entrapped diclofenac sodium. The drug encapsulation efficiency is up to about 50%. Less than 9% of drug has been released at pH 1.2 and the hydrogel beads sustain the drug release at pH 7.4 over 30 h. This shows the potential of CMSP/pectin hydrogel beads as carrier for colon‐targeted drug. © 2016 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2016 , 133, 43416. 相似文献
5.
Synthesis and characterization of ferroelectric side chain liquid crystal polymers bearing banana-shaped chiral mesogens 总被引:1,自引:0,他引:1
Long-Hai Wu Chwn-San Chu N. Janarthanan Chain-Shu Hsu 《Journal of Polymer Research》2000,7(2):125-134
A series of ferroelectric liquid crystal polymers having banana-shaped side chain mesogens were synthesized through photo-polymerization
of epoxide moiety. 2,5-disubstituted-thiophene sub-unit was used in synthesizing the banana-shaped monomers. These liquid
crystal compounds were characterized by NMR, differential scanning calorimetry (DSC) and optical polarized microscopy (POM).
Mesomorphism was investigated as a function of spacer units. All the synthesized low molar mass banana-shaped compounds exhibit
smectic blue phase, but chiral smectic C phase could be observed only on compounds having longer spacer. The clearing temperature
of low molar mass compounds fluctuated a little when spacer length varies. All polymers exhibit cholesteric mesophase and
an observable glass transition. These liquid crystalline compounds reveal strong photoluminescence at visible region (λmax = 475 nm for M9EPX) and have potential use in polarized organic light emitting diode materials. 相似文献
6.
A double slope floating cum tilted-wick solar still has been fabricated and transient theory of floating cum tilted-wick type
solar still has been proposed. Analytical expressions have been derived for the different temperatures components of the proposed
system. For elocution of the analytical results, numerical calculations have been carried out using the meteorological parameters
for a typical summer day in Coimbatore. Analytical expression results are found to be in the close agreement with the experimental
results. 相似文献
7.
Ganoderma is normally dried to extend its shelf life without using chemical preservative and to concentrate the medicinal value in the fruiting body. Convective hot air drying characteristics of Ganoderma tsugae Murrill were evaluated in hot air circulated oven at different drying temperatures, sizes, and air flow rates. The drying kinetics of Ganoderma tsugae in kidney shape and slices were investigated and compared at different drying conditions. The variation of effective moisture diffusivity values at decreasing moisture contents during drying was determined from the drying data. Four well-known thin-layer drying models were fitted to the experimental data and the Midilli model was found to satisfactory describe the drying characteristics of kidney-shaped Ganoderma tsugae. Ganoderma tsugae dried at 50°C with air velocity of 1.401 ms?1 showed the highest retention of crude ganoderic acid content compared to other drying conditions. 相似文献
8.
Janarthanan Supramaniam Darren Yi Sern Low See Kiat Wong Loh Teng Hern Tan Bey Fen Leo Bey Hing Goh Dazylah Darji Fatimah Rubaizah Mohd Rasdi Kok Gan Chan Learn Han Lee Siah Ying Tang 《International journal of molecular sciences》2021,22(11)
Cellulose nanofibers (CNF) isolated from plant biomass have attracted considerable interests in polymer engineering. The limitations associated with CNF-based nanocomposites are often linked to the time-consuming preparation methods and lack of desired surface functionalities. Herein, we demonstrate the feasibility of preparing a multifunctional CNF-zinc oxide (CNF-ZnO) nanocomposite with dual antibacterial and reinforcing properties via a facile and efficient ultrasound route. We characterized and examined the antibacterial and mechanical reinforcement performances of our ultrasonically induced nanocomposite. Based on our electron microscopy analyses, the ZnO deposited onto the nanofibrous network had a flake-like morphology with particle sizes ranging between 21 to 34 nm. pH levels between 8–10 led to the formation of ultrafine ZnO particles with a uniform size distribution. The resultant CNF-ZnO composite showed improved thermal stability compared to pure CNF. The composite showed potent inhibitory activities against Gram-positive (methicillin-resistant Staphylococcus aureus (MRSA)) and Gram-negative Salmonella typhi (S. typhi) bacteria. A CNF-ZnO-reinforced natural rubber (NR/CNF-ZnO) composite film, which was produced via latex mixing and casting methods, exhibited up to 42% improvement in tensile strength compared with the neat NR. The findings of this study suggest that ultrasonically-synthesized palm CNF-ZnO nanocomposites could find potential applications in the biomedical field and in the development of high strength rubber composites. 相似文献
9.
10.
Summary
An efficient method for the synthesis of PPV based polymers, poly ( 2,5-dimethyl-1,4-phenylene vinylene) (DMe-PPV) and poly
(2,5-dimethoxy-1,4-phenylene vinylene) (DOMe-PPV) were developed using 2,5-dimethyl-1,4-bis ( chloromethyl ) benzene and 2,5-dimethoxy
1,4-bis ( chloromethyl ) benzene via vapor phase pyrolysis and followed by vapor deposition polymerization. The structure
of polymer films were confirmed by FT-IR, solid state NMR and elemental analysis. Thermal gravimetry analysis reveals that
the precursor polymer films form a conjugated polymer after thermal conversion at 250°C. The optical and electrical properties
of the polymer films were investigated by UV-Vis absorption and photoluminescence spectroscopies. Electroluminescent devices
were fabricated using these polymers.
Received: 18 May 2000/Revised version: 21 July 2000/Accepted: 28 July 2000 相似文献