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Wai Shin Ho Cheng Seong Khor Haslenda Hashim Sandro Macchietto Jiří Jaromír Klemeš 《Clean Technologies and Environmental Policy》2014,16(5):957-970
This work proposes a novel approach called stand-alone hybrid system power pinch analysis (SAHPPA), which is particularly applicable for the design of off-grid distributed energy generation systems. The enhanced graphical tool employs new ways of utilising the recently introduced demand composite curve and supply composite curve while honouring and adapting fundamental energy systems engineering concepts. The SAHPPA method is capable of optimising the capacity of both the power generators and energy storage for biomass (i.e. non-intermittent) and solar photovoltaic (i.e. intermittent) energy technologies, which is a contribution to the emerging area of power pinch analysis. In addition, the procedure considers all possible efficiency losses in the overall system encompassing the charging–discharging and current inversion processes. 相似文献
24.
Khamirul Amin Matori Loy Chee Wah Mansor Hashim Ismayadi Ismail Mohd Hafiz Mohd Zaid 《International journal of molecular sciences》2012,13(12):16812-16821
We report on a recycling project in which α-Al2O3 was produced from aluminum cans because no such work has been reported in literature. Heated aluminum cans were mixed with 8.0 M of H2SO4 solution to form an Al2(SO4)3 solution. The Al2(SO4)3 salt was contained in a white semi-liquid solution with excess H2SO4; some unreacted aluminum pieces were also present. The solution was filtered and mixed with ethanol in a ratio of 2:3, to form a white solid of Al2(SO4)3·18H2O. The Al2(SO4)3·18H2O was calcined in an electrical furnace for 3 h at temperatures of 400–1400 °C. The heating and cooling rates were 10 °C/min. XRD was used to investigate the phase changes at different temperatures and XRF was used to determine the elemental composition in the alumina produced. A series of different alumina compositions, made by repeated dehydration and desulfonation of the Al2(SO4)3·18H2O, is reported. All transitional alumina phases produced at low temperatures were converted to α-Al2O3 at high temperatures. The X-ray diffraction results indicated that the α-Al2O3 phase was realized when the calcination temperature was at 1200 °C or higher. 相似文献
25.
Cenk Aktas Eva Dörrschuck Cathrin Schuh Marina Martinez Miró Juseok Lee Norbert Pütz Gunther Wennemuth Wolfgang Metzger Martin Oberringer Michael Veith Hashim Abdul-Khaliq 《Materials science & engineering. C, Materials for biological applications》2012,32(5):1017-1024
The effect of the micro- and nanotopography on vascular cell-surface interaction is investigated using nano- and microstructured Al2O3 as model substrate. Two different nanostructured Al2O3 surfaces composed of low density (LD) and high density (HD) nanowires (NWs) were synthesized by chemical vapour deposition (CVD) and commercially available microstructured Al2O3 plates were used for comparison. A clear diverging response of human umbilical vein endothelial cells (HUVEC) and human umbilical vein smooth muscle cells (HUVSMC) was observed on these nano- and microstructured surfaces. LD Al2O3 NWs seem to enhance the proliferation of HUVECs selectively. This selective control of the cell-surface interaction by topography may represent a key issue for the future stent material design. 相似文献
26.
Ishtiaq Hassan Abdul Razzaq Ghumman Hashim Nisar Hashmi Abdul Sattar Shakir 《Civil Engineering and Environmental Systems》2013,30(4):365-376
This study has been carried out to forecast the impact of global warming on the precipitation pattern of Saudi Arabia by the end of year 2100. Simulation has been done using EdGCM model software (with available 8×10 resolution) developed at Columbia University on which there have been produced global precipitation maps for the seasonal and annual averages for the last 5 years (2096–2100). For each map, EdGCM grid values surrounding Saudi Arabia are used as input to one of the tools of Eagle point software called surface modelling (SM). SM is a new approach for downscaling global climate model results. SM software modelled out isohyets at 0.2 mm/day interval. The results indicate that the present pattern of precipitation (more in winter and less in summer) is going to change by almost equal occurrence of precipitation in all seasons for double_CO2 (2CO2) experiment. The 2CO2 experiment indicates an increase of about 16.05% over the annual average precipitation across the country. 相似文献
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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
28.
Mohd. Hashim Sagar E. Shirsath S.S. Meena Pramod Bhatt R.K. Kotnala Shalendra Kumar Ravi Kumar Dachepalli Ravinder Alimuddin 《Ceramics International》2014
The Cr3+ ions doped multi-oxide ZnFe2−xCrxO4 ferrite nanoparticles have been synthesized by chemical co-precipitation method. Site occupancies of Zn2+, Cr3+ and Fe3+ ions were analyzed using X-ray diffraction data and Buerger's method. The effect of the constituent phase variation on the magnetic hysteresis behavior was examined by saturation magnetization which decreases with the increase in Cr3+ content in place of Fe3+ ions at octahedral B-site. Typical blocking temperature (TB) around 90 K was observed by zero field cooling and field cooling magnetization study. Room temperature Mössbauer spectra show two paramagnetic doublets (tetrahedral and octahedral sites). The isomer shifts of both doublets decrease whereas quadrupole splitting and relative area of tetrahedral A-site increases with increasing Cr3+ substitution. The dielectric constant (measured on compositions x=0, 0.4, 0.8 and 1.0) increases when the temperature increases as in the semiconductor. This behavior is attributed to the hopping of electrons between Fe2+ and Fe3+ ions with a thermal activation. 相似文献
29.
Showkat A. Bhawani Othman Sulaiman Ziya A. Khan Rokiah Hashim Mohamad N. M. Ibrahim 《Journal of surfactants and detergents》2011,14(2):301-305
The mutual separation of a mixture of cetyltrimethyl ammonium chloride (CTAC), methyl trioctyl ammonium bromide (MTOB), dodecyltrimethyl
ammonium chloride (DTAC), benzyltrimethyl ammonium chloride (BTAC) and tetrabutyl ammonium bromide (TBAB), was achieved on
silica high performance thin layer chromatographic plates using dimethyl sulfoxide with aqueous sodium-l-tartrate dibasic dihydrate as the solvent system. The effect of concentration of sodium-l-tartrate dibasic dihydrate on the mobility of all the five quaternaries was examined. The limit of detection of CTAC, MTOB,
DTAC, BTAC and TBAB was estimated as 0.6, 0.6, 0.3, 0.6 and 0.3 μg/zone, respectively. The method developed was utilized to
identify these surfactants in different spiked water samples after their preliminary separation. 相似文献
30.
Abstract The importance of liquid viscosity in chemical process design makes it one of the most measured transport properties. Nevertheless, in the pure-component database, no experimental data on liquid viscosity for nearly 50% of the compounds are available. Therefore, prediction methods for liquid viscosity of alkenes over a wide range of absolute temperature for each components are necessary. Moreover, experimental data measured at lower temperatures are often extrapolated to higher temperatures with erroneous results. To improve liquid viscosity prediction of experimental data to temperatures and carbon numbers, we propose an empirical rule for estimating the viscosity of alkenes compounds. A predictive method, based physical properties (absolute temperature and carbon numbers) as its inputs, to correlate liquid viscosity by the statistical analysis is proposed. For a group of 19 compounds, the mean average absolute deviation was 4.6% for 118 data points. These values are better than other predictive methods and show that the statistical analysis model is stable and can be used to obtain good predictions for compounds that were not used in the model calibration. 相似文献