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ABSTRACT: Electric vehicles (EVs) and compressed natural gas vehicles (CNGVs), which are mainly coal-based and natural gas-based, are the two most widely proposed replacements of gasoline internal combustion engine vehicles (ICEVs) in China. We examine fuel-cycle emissions of greenhouse gases (GHGs), PM2.5, PM10, NOx and SO2 of CNGVs and EVs relative to gasoline ICEVs and hybrids (HEVs), by Chinese province. CNGVs can currently reduce emissions of GHGs, PM10, PM2,5, NOx, and SO2 by approximately 6%, 7%, 20%, 18% and 26%, respectively. EVs can reduce GHG emissions by 20%, but increase PM10, PM2.5, NOx, and SO2 emissions by approximately 360%, 250%, 120%, and 350%, respectively. Nevertheless, results vary significantly by province. Regarding their contribution to national emissions, PM increases from EVs are unimportant, because light-duty passenger vehicles contribute very little to overall PM emissions nationwide (0.05%); however, their NOx and SO2 increases are important. Since China is striving to reduce power plant emissions, EVs are expected to have equivalent or even lower SO2 and NOx emissions relative to ICEVs in the future (2030). Before then, however, EVs should be developed according to the cleanness of regional power mixes. This would lower their SO2 and NOx emissions and earn more GHG reduction credits.
Environmental Science & Technology 12/2012; · 4.80 Impact Factor
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ABSTRACT: Vssilk 5 is a gene encoding a component protein of the silk produced by the larvae of the yellow hornet (Vespa simillima, Vespinae, Vespidae). In this study, we deduced the complete cDNA sequence of Vssilk 5. It was found that 2 silk proteins, Vssilk 5 N and Vssilk 5 C, in the cocoon of the yellow hornet are both encoded by the Vssilk 5 gene. Vssilk 5 N and 5 C are the N- and C-terminal regions, respectively, of the Vssilk 5 pro-protein (Vssilk 5p). The complete amino acid sequences of Vssilk 5 N and Vssilk 5 C were deduced. Although a non-repetitive amino acid sequence and coiled-coil structure are properties common to the major components of silk proteins produced by the larvae of the social superfamilies Apoidea and Vespoidea of the Apocrita, nearly the entire sequence of Vssilk 5 C consisted of a repeated sequence of amino acids, and the calculated coiled-coil probability for this protein was low. Vssilk 5 N is a protein without a repetitive amino acid sequence and has a low coiled-coil probability. Moreover, we found a water soluble protein, Vssilk 5S that is likely segmented from Vssilk 5 C and contains an N-terminal sequence identical to that of Vssilk 5 C.
Comparative biochemistry and physiology. Part B, Biochemistry & molecular biology 09/2011; 161(1):17-24. · 1.61 Impact Factor
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ABSTRACT: Complete amino acid sequences of the four major proteins (Vssilk 1-4) of silk (hornet silk) obtained from yellow hornet ( Vespa simillima , Vespinae, Vespidae) cocoons have been determined. The native structure of the hornet silk (HS), in which Vssilk 1-4 have an alpha-helix domain with coiled-coil alpha-helices and a beta-sheet domain, is restored when hornet silk gel films (HSGFs) are formed by pressing and drying HS hydrogel. Necking occurs when dry HSGFs are drawn; however, wet HSGFs can be uniaxially drawn with a draw ratio (DR) of 2. Drawing helps obtain high-performance films with a maximum tensile strength and tensile modulus of 170 MPa and 5.5 GPa, respectively. Drawing-induced changes in the orientation and conformation of the coiled-coil structure are investigated.
Biomacromolecules 02/2010; 11(4):1009-18. · 5.48 Impact Factor
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ABSTRACT: We compared the components of hornet silk - a fibrous protein occurring in the cocoons produced by hornet larvae - among 6 species of the genus Vespa inhabiting Japan: V. simillima, V. dybowskii, V. crabro, V. mandarinia, V. ducalis, and V. analis. From the sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE), N-terminal amino acid sequence analysis, and 5'-RACE, it was found that the major component proteins composing hornet silk could be divided into 6 groups. Among these 6 proteins, 5 proteins were common to the hornet silks of all 6 Vespa species. The SDS-PAGE major band corresponding to the remaining protein was observed only in the hornet silks of V. mandarinia and V. ducalis. This correspondence between V. mandarinia and V. ducalis can probably be explained in terms of the phylogenetic relationships of the Vespa species.
Comparative Biochemistry and Physiology Part B Biochemistry and Molecular Biology 11/2008; 151(2):221-4. · 1.92 Impact Factor
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ABSTRACT: Industrial trials detailed in a riser−downer coupling reactor proposed for the fluid catalytic cracking (FCC) process are presented in this paper. The trials are based on the fundamental research of hydrodynamics, mixing behaviors, and laboratory-scale hot experiments described in our previous investigations. Compared with the riser reactor with the same feeds and catalyst, the LPG and propylene yield increased by 8.15 and 4.30 wt %, respectively. The gasoline octane number likewise reached 94.8 with 28 wt % olefin content. However, dry gas is significantly suppressed, and the coke has little change in yield even with the increased catalyst to oil ratio. With some gasoline recycling, the LPG and propylene yield increased by 11.45 and 5.06 wt %, respectively, and the olefin content in gasoline significantly decreased to 22 wt %; the high octane number (95.4) is maintained. The computational fluid dynamics (CFD) coupled with a 6-lump kinetic model is also applied to simulate the FCC process for the industrial trials. The yield of propylene and butylene and the temperature profile along the axis direction demonstrated consistency between the simulation results and the experimental data.
10/2008;
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ABSTRACT: A CuO−ZnO−Al2O3−ZrO2 + HZSM-5 physical mixture bifunctional catalyst with a high activity for dimethy ether (DME) synthesis was used for CO2 hydrogenation. Various factors that affect catalyst activity, including the reaction temperature, pressure, and space velocity, were investigated. CO2 conversion reached 0.309, and DME and methanol yields were 0.212 and 0.059 with a stoichiometric ratio of H2 to CO2 of 3 at 523 K, 5 MPa, and a space velocity of 6000 mL/(g cat·h). Well-studied kinetic models for methanol synthesis and methanol dehydration, respectively, were used to fit the experimental data and the kinetic parameters in the rate equations for DME synthesis were obtained by regression. A simulated process for CO2 hydrogenation indicated that a higher DME yield can be obtained with CO recycle that will also give a CO-free product.
07/2008;
