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41.
Directional distance function (DDF) is a recognized technique for measuring efficiency while incorporating undesirable outputs. This approach allows for desirable outputs to be expanded while undesirable outputs are contracted simultaneously. A drawback of the DDF approach is that the direction vector to the production boundary is fixed arbitrarily, which may not provide the best efficiency measure. Therefore, this study extends the previous framework of efficiency analysis to introduce a new slacks-based measure of efficiency called the scale directional distance function (SDDF) approach. This new approach determines the optimal direction to the frontier for each unit of analysis and provides dissimilar expansion and contraction factors to achieve a more reasonable eco-efficiency score. This new approach is employed to measure the eco-efficiency of the Malaysian manufacturing sector. In addition, the paper demonstrates the use of the new approach to establish target values for the reduction/expansion of outputs in order for the inefficient DMUs to achieve full eco-efficiency. The results indicate that Melaka, Pulau Pinang, Negeri Sembilan, Sabah, Sarawak and Labuan have attained full eco-efficiency while Terengganu is the least eco-efficient. The overall eco-efficiency of the manufacturing sector in Malaysia is 80.5 % with wide variations across the states. 相似文献
42.
Muneer Aziz Saleh Ahmad Termizi Ramli Yasser Alajerami Mohammed Damoom Abubakar Sadiq Aliyu 《Isotopes in environmental and health studies》2014,50(1):103-113
The radiation survey of the ambient environment was conducted using two gamma detectors, and the measurement results were used in the computation of the mean external radiation dose rate, mean-weighted dose rate and annual effective dose, which are 144 nGy h?1, 0.891 mSv y?1 and 178 μSv, respectively. A high-purity germanium detector was used to determine the activity concentrations of 232Th, 226Ra and 40K in soil samples. The results of the gamma spectrometry of the soil samples show radioactivity concentration ranges from 19±1 to 405±13 Bq kg?1 with a mean value of 137±5 Bq kg?1 for 232Th, from 21±2 to 268±9 Bq kg?1with a mean value of 78±3 Bq kg?1 for 226Ra and from 23±9 to 1268±58 Bq kg?1 with a mean value of 207±13 Bq kg?1 for 40K. Radium equivalent activity (Raeq) and external hazard index (Hex) were 290 Bq kg?1 and 0.784, respectively, which were safe for the population. The mean lifetime dose and lifetime cancer risk for each person living in the area with average lifetime (70 y) were 12.46 mSv and 7.25×10?4 Sv year, respectively. The results were compared with values given in United Nations Scientific Committee on the Effects of Atomic Radiation 2000. 相似文献
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44.
Hossein Moayedi Sina Kazemian Amir Hossein Vakili Soheil Ghareh Ramli Nazir 《Journal of Dispersion Science and Technology》2014,35(2):273-282
Electroflotation is an unconventional separation process owing its name to the bubbles generation method (i.e., electrolysis of the aqueous medium) caused by the hydrogen and hydroxide development. Collecting the colloidal particles in surface water has been a long-term issue all over the world, because of their adverse influence. In the present research, the electroflocculation technique have been use to collect the humus particles throughout the polluted wastewater. The uses of different chemical additives namely, Al2(SO4)3, Al(OH)3, CaCl2, CaO, and Na2SiO3 were also successfully examined and enhanced the electroflocculation technique. Although high negatively surface electrical charge of humus causes difficulties in the conventional flocculation and coagulation technique, it enhances the flocculation process when the electroflocculation techniques have been used. The results of both Jar test and electroflocculation technique are further compared. It can be concluded that the polluted water were fully decontaminated (i.e., all of the suspended colloids through the water were removed) by using the electroflocculation technique. The removal rate after electroflocculation test were 91.8%, 98%, 93.5%, 85.3%, 95.4%, and 94% for neutral, Al2(SO4)3, Al(OH)3, CaCl2, CaO, and Na2SiO3, respectively. While the removal rate after Jar test were 84.8%, 83.79%, 71.44%, 84.83%, 77.09%, and 77.09% for neutral, Al2(SO4)3, Al(OH)3, CaCl2, CaO, and Na2SiO3, respectively. 相似文献
45.
N. N. Garba A. T. Ramli M. A. Saleh M. S. Sanusi H. T. Gabdo 《Journal of Radioanalytical and Nuclear Chemistry》2014,302(1):201-209
Terrestrial gamma radiation dose rates (TGRD) of Kelantan State were measured in situ using a portable [NaI(TI)] micro roentgen (µR) survey meter. The TGRD rates ranged between 44 and 500 nGy h?1 with a mean value of 209 ± 8 nGy h?1. The distribution of these measurements in various districts of the state shows the statistically the influence of geology and soil types on the dose rate values. The data obtained could be used in formulating safety standard and radiological guidelines. 相似文献
46.
M. Pardede R. Hedwig M.M. Suliyanti Z.S. Lie T.J. Lie D.P. Kurniawan K.H. Kurniawan M. Ramli K. Fukumoto H. Niki S.N. Abdulmadjid N. Idris T. Maruyama K. Kagawa M.O. Tjia 《Applied physics. B, Lasers and optics》2007,89(2-3):291-298
An experimental study has been performed to demonstrate the advantage of employing ambient helium gas in the spectral quality
improvement of hydrogen emission in laser-induced plasma from zircaloy-2 samples at both atmospheric and low gas pressure.
It was further shown that the optimal results achieved in the two pressure regimes require the adoption of different sets
of experimental parameters consisting of the laser energy, the focusing lens position and the detection gate delay. A strictly
linear calibration line with extrapolated zero intercept was nevertheless exhibited in the case of atmospheric gas pressure
only. Additional time-evolution measurement of the emission intensities of hydrogen, helium and zirconium clearly suggests
a distinctly different excitation mechanism for hydrogen atoms associated with the presence of ambient helium atoms and their
meta-stable excited state.
PACS 52.38 Mf 相似文献
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M. Ramli K. Kagawa S.N. Abdulmadjid N. Idris W.S. Budi M.A. Marpaung K.H. Kurniawan T.J. Lie M.M. Suliyanti R. Hedwig M. Pardede Z.S. Lie M.O. Tjia 《Applied physics. B, Lasers and optics》2007,86(4):729-734
A study of the experimental results on the plasma emissions of water and ethanol vapor samples, induced by Nd:YAG laser in
ambient helium and nitrogen gases at atmospheric pressure, is presented here. The result reveals distinct geometrical and
spectral characteristics of the plasma emissions generated in the helium gas when compared to those observed from nitrogen
gas plasma. Most remarkable is the narrow line width and low continuum background exhibited by emission lines of the analyte
atoms from helium plasma, including the hydrogen emission line which is known to suffer from notorious broadening effects
in conventional laser induced breakdown spectroscopy (LIBS). It is further shown on the basis of the measured spatial distributions
and time profiles of the emission intensities, that the excellent spectral quality is attained by taking advantage of the
meta-stable excited state of helium atoms for the delayed excitation of the hydrogen and other analyte atoms, this allows
the detection of those atomic emissions to be performed under more favorable conditions. The result of this study has thus
demonstrated the feasibility of achieving high-quality spectrochemical analysis, including hydrogen analysis with laser-induced
helium gas breakdown spectroscopy.
PACS 52.38.Mf 相似文献
49.
Mohamed Mahmoud Nasef Seyedeh Sara Alinezhad Ramli Mat Parvaneh Shabanzadeh Rubiyah Yusof 《高分子科学杂志,A辑:纯化学与应用化学》2016,53(9):557-565
A simple and flexible method was used to develop new alkaline polymer catalyst through radiation induced grafting of glycidylmethacrylate (GMA) onto polyethylene/polypropylene (PE/PP) nonwoven sheet followed by amination reaction and alkalisation. The chemical structure and morphology of catalyst was evaluated by Fourier transform-infrared (FTIR), scanning electron microscopy (SEM), X-ray diffraction (XRD) and thermal gravimetric analyzer (TGA). The catalyst was examined for the transesterification of triacetin/methanol mixtures in a batch mode and the obtained methyl ester was detected by GC-MS. In order to optimize the reaction parameters towards getting the higher yield, an artificial neural network (ANN) was used to develop a non-linear model correlating the four independent reaction parameters including catalyst dosage, triacetin/methanol molar ratio, reaction time and temperature. The maximum conversion obtained via the simulated annealing (SA) algorithm was 86.2% at the optimal conditions of 5.01 wt% catalyst dosage, triacetin/methanol 1:12 molar ratio, 8 h reaction time and 62.8°C temperature. Upon using these optimal conditions in the experimental reaction, the conversion of as high as 85% was achieved. These results suggest that the simply modified low cost PE/PP fibrous sheet has a potential to catalyze biodiesel production. Moreover, the combined ANN-SA modelling method is highly effective in predicting the conversion of transesterification reaction and optimizing its parameters. 相似文献
50.
Ethylene Conversion to Higher Hydrocarbon over Copper Loaded BZSM-5 in the Presence of Oxygen 总被引:1,自引:0,他引:1 下载免费PDF全文
The successful production of higher hydrocarbons from methane depends on the stability or the oxidation rate of the intermediate products. The performances of the BZSM-5 and the modified BZSM-5 catalysts were tested for ethylene conversion into higher hydrocarbons. The catalytic experiments were carried out in a fixed-bed micro reactor at atmospheric pressure. The catalysts were characterized using XRD, NH3-TPD, and IR for their structure and acidity. The result suggests that BZSM-5 is a weak acid. The introduction of copper into BZSM-5 improved the acidity of BZSM-5. The conversion of ethylene toward higher hydrocarbons is dependent on the acidity of the catalyst. Only weaker acid site is required to convert ethylene to higher hydrocarbons. The loading of Cu on BZSM-5 improved the selectivity for higher hydrocarbons especially at low percentage. The reactivity of ethylene is dependent on the amount of acidity as well as the presence of metal on the catalyst surface. Cu1%BZSM-5 is capable of converting ethylene to higher hydrocarbons. The balances between the metal and acid sites influence the performance of ethylene conversion and higher hydrocarbon selectivity. Higher loading of Cu leads to the formation of COx. 相似文献