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41.
We purified and characterized Type I collagen from the scales of the Pacific saury (Cololabis saira) and compared it with collagen from other organisms. Subunit composition of C. saira collagen (2α1 + α2) was similar to that of red sea bream (Pagrus major) and porcine collagen. C. saira collagen did not form a firm gel after neutralization of pH in solution. The temperature of denaturation (24–25 °C) of C. saira collagen was slightly lower than that of P. major collagen (26–27 °C). The contents of proline and hydroxyproline were lower in red sea bream and Pacific saury collagen than in porcine collagen. Circular dichroism spectra and Fourier-transformed infrared spectra showed that heat denaturation caused unfolding of the triple helices in all three collagens.  相似文献   
42.
The nettle moth Monema flavescens (Limacodidae) is a defoliator of fruit trees, such as Chinese plum and persimmon. The larvae of this species have spines containing a poison that causes serious irritation and inflammation in humans. Coupled gas chromatography-electroantennogram detection and gas chromatography/mass spectrometry analyses of a crude pheromone extract, combined with derivatization, indicated that female moths produced 8-decen-1-ol and 7,9-decadien-1-ol at a ratio of approximately 9:1. The E configuration of the double bonds was assigned for both components from infrared spectra, recorded on a gas chromatograph/Fourier transform-infrared spectrophotometer equipped with a zinc selenide disk cooled to ?30 °C. The monoenyl and dienyl alcohols had absorptions characteristic of E geometry at 966 and 951 cm?1, respectively. A band chromatogram at 951 cm?1 was useful for distinguishing geometric isomers, because terminal conjugated diene are difficult to resolve, even on high polarity columns. Furthermore, we identified the Z configuration of the same 7,9-dienyl alcohol secreted by another nettle moth, Parasa lepida lepida, through the absence of this absorption. In field trials, lures baited with a 9:1 mixture of (E)-8-decen-1-ol and (E)-7,9-decadien-1-ol attracted M. flavescens males. Furthermore, the field trials indicated that contamination with the (Z)-diene reduced catches to the pheromone mixture more than did contamination with the (Z)-monoene.  相似文献   
43.
Summary The MgCl2-supported TiCl3 catalyst containing a small amount of Ti(about 0.1 wt.%) was prepared by treating the mixture of MgCl2 and TiCl3 3py with an excess amount of AlEt2Cl. Propene polymerization was conducted at 40°C by using AlEt3 as cocatalyst. The catalyst system was found to be highly active, which gave atactic polypropylene  相似文献   
44.
In this paper, study of the biosorption of Cd(2+) and Pb(2+) by nonliving Laminaria japonica in a batch adsorption system is described. The content of acidic sites and the dissociation constant of carboxylic acid functional groups (metal-binding site) of L. japonica were experimentally determined by conductometric and potentiometric titrations and theoretically predicated by using monodentate and bidentate binding models. The models are based on the monodentate or bidentate binding reactions of bivalent metal ions to acidic sites. The acidic site content and carboxylic acid dissociation constants determined are 1.25 and 0.18 mmol L(-1), respectively. The results showed that the bidentate adsorption model fits well the biosorption of bivalent metal ions onto L. japonica with the bidentate binding constants for Cd(2+) and Pb(2+) being 5.72 × 10(3) and 6.24 × 10(4) L mol(-1), respectively. The adsorption process of L. japonica followed the pseudo-second-order kinetics.  相似文献   
45.
The ZrC-coated UO2 particle is a promising fuel for high-temperature gas-cooled reactors. Particle fuels with multiple layers of pyrolytic carbon and ZrC have been irratiation-tested to a maximum fast-neutron fluence exceeding 2 × 1025/m2 ( E < 29 fJ). In-reactor fission-gas release measured at a burnup of 1.5 at.% was minimal. The failure fraction by postirradiation examination was null for all samples. The ZrC-coated particles at 4 at.% burnup were postirradiation heated to 2400°C/min without failure until after 6000 s at the maximum temperature. It was found that the ZrC layer could sustain a large strain at such high temperatures. The behavior is in strong contrast with that of SiC of standard Triso coating, which is brittle to very high temperatures.  相似文献   
46.
Layer-by-layer formation for π-conjugated azomethine multilayers bonded on substrates was investigated. The multilayers were synthesized using ethanol (EtOH) and dichloromethane (DCM) as reaction solvents. The multilayer characteristics were analyzed using UV-vis absorption spectroscopy, ellipsometric thickness, and atomic force microscopy. The absorption spectra and ellipsometric thicknesses of multilayers formed using EtOH and DCM were compared. The results indicate that EtOH is more suitable than DCM for such layer-by-layer formation. In addition, bandgaps estimated from the absorption edge of multilayers were investigated. The results indicate that the bandgap decreases as the number of benzene rings contained in the molecular chain of the multilayer increases. Also, a multilayer with four benzene rings bonded on a substrate had a bandgap close to that of a polymer with a similar chemical structure.  相似文献   
47.
Considerable deposition of (137)Cs was observed in the northwestern coastal area of Japan in March 2002. Since there were no nuclear explosions or serious nuclear accidents in the early 2000s, transport of previously contaminated dust appears to be the only plausible explanation for this event. In March 2002, there was a massive sandstorm on the East Asian continent, and the dust raised by the storm was transported across the sea to Japan. This dust originated in Mongolia and northeastern China, in an area distant from the Chinese nuclear test site at Lop Nor or any other known possible sources of (137)Cs. Our radioactivity measurements showed (137)Cs enrichment in the surface layer of grassland soils in the area of the sandstorm, which we attributed to accumulation as a result of past nuclear testing. We suggest that the grassland is a potential source of (137)Cs-bearing soil particles. Since the late 1990s, this area has experienced drought conditions, resulting in a considerable reduction of vegetation cover. We attribute the prodigious release of (137)Cs-bearing soil particles into the atmosphere during the sandstorm and the subsequent deposition of (137)Cs in Japan to this change.  相似文献   
48.
The sweet potato vine borer moth, Omphisa anastomosalis (Pyraloidea: Crambidae), is a serious pest in tropical and subtropical Asia-Pacific regions. In previous work using a population from Okinawa, Japan, (10E,14E)-10,14-hexadecadienal (E10,E14-16:Ald) was identified as the major pheromone component, with hexadecanal, (E)-10-hexadecenal, and (E)-14-hexadecenal as minor components. However, traps baited with the synthetic compounds were less effective at attracting males in the field than those baited with virgin females. While Pyraloidea females usually produce only Type I pheromone components (unsaturated fatty alcohols and their derivatives), the pheromones of some Pyraloidea species have been shown to involve a combination of both Type I and Type II components (unsaturated hydrocarbons and their epoxides). We examined an extract of the pheromone glands of female O. anastomosalis from Vietnam by gas chromatography coupled to mass spectrometry and detected (3Z,6Z,9Z)-3,6,9-tricosatriene (Z3,Z6,Z9-23:H) in addition to the compounds identified previously. All four isomers of 10,14–16:Ald were synthesized. A mixture of synthetic E10,E14-16:Ald and Z3,Z6,Z9-23:H in a ratio of 1:0.2–1:2 was attractive to male moths in Vietnam, indicating the strong synergistic effect of the Type II compound. Addition of the other minor pheromone components to the binary blend did not increase the number of male moths captured. Combinations of Z3,Z6,Z9-23:H with the other three geometrical isomers of E10,E14-16:Ald attracted no males, further substantiating the 10E,14E configuration of the natural diene component. E10,E14-16:Ald mixed with other polyunsaturated hydrocarbons showed that mixtures that included a C21 triene, a C22 triene, or a C23 pentaene attracted as many males as did the mixture with Z3,Z6,Z9-23:H. The identification of a highly attractive sex pheromone will help in developing efficient strategies for monitoring and control of O. anastomosalis populations in sweet potato fields.  相似文献   
49.
The adsorption onto polymer microspheres of bovine fibrinogen (BFb) containing both dimeric and monomeric species was examined using various homopolymer, copolymer, and poly(2-hydroxyethyl methacrylate)/polystyrene composite microspheres which were produced by the emulsifier-free (seeded) emulsion polymerization technique. The preferential adsorption of the BFb dimer was clearly observed in an optimum region of the surface hydrophilicities of the polymer microspheres. The preferential adsorption of the BFb dimer onto the composite polymer microspheres having heterogeneous surfaces with both hydrophilic and hydrophobic parts was more remarkable than that onto the homopolymer and copolymer microspheres having homogeneous surfaces. The behavior is discussed in comparison with those for bovine serum albumin and human γ-globulin.  相似文献   
50.
A 5 kW CW CO2 laser using a negative-branch unstable resonator (M=-1.5) is proposed and characterized experimentally. The resonator consists of a stepwise variable reflecting output coupler, called the phase-unifying output coupler, and a total reflector. A 5 kW CW laser beam with diffraction limited quality (2&thetas;=0.45 mrad) is obtained and affected by the focal point in the resonator. The misalignment angle to reduce the laser power to 95% is improved by a factor of 19 compared with a positive-branch unstable resonator (M=1.5) with a phase-unifying output coupler at the same resonator length  相似文献   
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