Effects of processing and cooking on the levels of pesticide residues in soybean samples

The effects of processing and cooking on the levels of pesticide residues in soybean samples were investigated for 14 pesticides in pre-harvest samples. On soaking, the transfer ratios (%, total pesticide residue amount in product/that in soybean) of soaked soybean were greater than 60% for most of the pesticides investigated. The transfer ratio of soymilk ranged from 37% to 92%, and that of tofu ranged from 7% to 63%. The processing factor (Pf, the concentration (mg/kg) of pesticide in product/that in soybean) of tofu ranged from 0.026 to 0.28. These values varied among pesticides. There was a high correlation between the log P(ow) and the transfer ratio of tofu. The test described here should be useful to obtain the transfer ratios of pesticide residues in processing and/or cooking steps.     

Application of electron beam for the reduction of PCDD/F emission from municipal solid waste incinerators

The electron-beam technology was applied to reduce the emission of polychlorinated dibenzo-p-dioxins (PCDD) and polychlorinated dibenzofurans (PCDF) in a flue gas of 1000 m(3)N/h from the municipal solid waste incinerator (MSWI) at a temperature of 200 degrees C. More than 90% decomposition of PCDD/Fs was obtained using an electron accelerator at a dose of 14 kGy. The decomposition was initiated through reactions with OH radicals produced by the irradiation of flue gases, followed by oxidation such as the ring cleavage of the aromatic ring, the dissociation of ether bond, and dechlorination. The cost analysis estimated that the electron-beam system can cut the annualized cost by approximately 50% for the treatment of PCDD/Fs in a pre-dusted MSWI flue gas as compared with a bag-filter system when operating on electricity generated from an incineration. Electron-beam technology is an economically and technologically useful method for reducing PCDD/Fs in an incineration flue gas.     

Numerical prediction of fraction of eutectic phase in Sn−Ag−Cu soldring using the phase-field method

A combination of macroscale solidification simulation and phase-field calculation is employed to predict the volume fraction of the eutectic phase in Sn-4.0 mass% Ag-XCu solder alloys (X=0.5–1.1 mass%). The solidification simulation incorporates the cooling rate in the phase-field simulation. We assume the residual liquid solidifies as eutectic phase when the driving force for the nucleation of Cu₆Sn₅ amounts to a critical value, which is determined based on the experimental data. Though the calculation results depend on the experimental data, the obtained fractions are about 40% for 0.5 mass% Cu and more than 90% for 1.1 mass% Cu alloy, which shows good agreement with the experimental data.     

The effect of heat sealing temperature on the properties of OPP/CPP heat seal. I. Mechanical properties

The effect of heat sealing temperature on the mechanical properties and morphology of OPP/CPP laminate films was investigated. The laminated films were placed in an impulse type heat sealing machine with both CPP sides facing each other. The temperatures investigated ranged from 100 to 250°C. T‐peel and tensile tests in combination with SEM were used to characterize the heat seals. A minimum seal initiation temperature of 120°C was identified for OPP/CPP laminate heat sealing. Peel strength increased sharply from zero at 110°C to maximum at 120°C, after which a gradual decrease was observed. Tensile strength initially increased until 120°C, after which it gradually decreased until 170°C and assumed a constant value beyond that. The initial rise has been associated to cold crystallization, while the reduction between 120°C and 170°C was due to relaxation in molecular orientation. Beyond 170°C, all the orientation in the laminate has been lost so orientation effects are nullified. Morphological studies with SEM revealed that seals were partially formed at lower temperatures, while the laminates were totally fused together at high temperatures, with intermediate temperatures showing properties that lie in between. © 2005 Wiley Periodicals, Inc. J Appl Polym Sci 97: 753–760, 2005     

Characterization of electrode/electrolyte interface for lithium batteries using in situ synchrotron X-ray reflectometry—A new experimental technique for LiCoO2 model electrode

A new experimental technique was developed for detecting structure changes at electrode/electrolyte interface of lithium cell using X-ray reflectometry and two-dimensional model electrodes with a restricted lattice-plane. The electrodes were constructed with an epitaxial film of LiCoO₂ synthesized by pulsed laser deposition method. The orientation of the epitaxial film depends on the substrate plane; the 2D layer of LiCoO₂ is parallel to the SrTiO₃ (1 1 1) substrate (_(0 0 3)LiCoO₂//_(1 1 1)SrTiO₃)$({(003)}_{\text{LiCo}{\text{O}}_2}//{(111)}_{\text{SrTi}{\text{O}}_3})$, while the 2D layer is perpendicular to the SrTiO₃ (1 1 0) substrate (_(1 1 0)LiCoO₂//_(1 1 0)SrTiO₃)$({(110)}_{\text{LiCo}{\text{O}}_2}//{(110)}_{\text{SrTi}{\text{O}}_3})$. The anisotropic properties were confirmed by electrochemical measurements. Ex situ X-ray reflectivity measurements indicated that the impurity layer existed on the as-grown LiCoO₂ was dissolved and a new SEI layer with lower density was formed after soaking into the electrolyte. In situ X-ray reflectivity measurements indicated that the surface roughness of the intercalation (1 1 0) plane increased with applying voltages, while no significant changes in surface morphology were observed for the intercalation non-active (0 0 3) plane during the pristine stage of the charge–discharge process.     

Efficiently activated carbon fiber derived from grafted novoloid fiber

Graft copolymerization of methyl methacrylate onto novoloid fiber was carried out by the electron beam mutual irradiation method. The characteristics of the grafted fiber were almost the same as those of the original novoloid fiber. The grafted fiber was carbonized and activated to yield an efficiently activated carbon fiber. The yield and the specific surface area of the activated carbon fiber, derived from the grafted novoloid fiber, were much greater than those derived from the original novoloid fiber. This is because grafted poly(methyl methacrylate) decomposes into monomer and gaseous products, forming pores on the surface and inside of the novoloid fiber on heating. © 1993 John Wiley & Sons, Inc.     

Molecular weights and molecular weight distributions of irradiated cellulose fibers by gel permeation chromatography

Radiation degradation of cellulose fibers was investigated by gel permeation chromatography (GPC). Scoured cotton of Mexican variety (cellulose I), Polynosic rayon (cellulose II), and their microcrystalline celluloses obtained by hydrolysis of the original fibers were irradiated by Co-60 γ-rays under vacuum or humid conditions. The irradiated samples were then nitrated under nondegradative conditions. The molecular weights and molecular weight distributions were measured by GPC using tetrahydrofran as solvent. The relationship between molecular weight and elution count was obtained with cellulose trinitrate standards fractionated by preparative GPC. The degree of polymerization of the fibers decreased with increasing irradiation dose, but their microcystalline celluloses were only slightly degraded by irradiation, especially in microcrystalline cellulose from cellulose I. Degradation of the fibers irradiated under humid conditions was less than that irradiated under vacuum. It was found that the G-values for main-chain scission for the irradiated cellulose I, cellulose II, microcrystalline cellulose I, and microcrystalline cellulose II were 2.8, 2.9, less than 1, and 2.9, respectively, but the G-value for main-chain scission for the irradiated cellulose II was increased to 11.2 at irradiation doses above 3 Mrad. Consequently, it is inferred that cellulose molecules in the amorphous regions are degraded more readily, and the well-aligned molecules in crystalline regions are not as easily degraded by irradiation.     

Increased leukocyte aggregates are associated with atherosclerosis in patients with hemodialysis

Little data are available on the role of blood rheology in atherosclerosis in hemodialysis (HD) patients. This study sought to assess the relationship between leukocytes conjugated with platelets (leukocyte aggregates [LA]) and atherosclerosis in patients with HD. The present study included 118 patients on HD. As surrogate markers of atherosclerosis, aortic stiffness measured by brachial-ankle pulse wave velocity, and carotid intima-media thickness (IMT) were measured. As an assessment of LA, a method, microchannel array flow analyzer, which makes it possible to directly observe the flow of blood cell elements through the microchannel, was used. We measured a number of LA during 50 μL flow of whole blood through microchannels. In 12 age-matched healthy individuals, a number of LA during 50 μL flow of whole blood was 25.7±5.4, whereas in HD patients it was significantly increased up to 48.2±16.4 (P<0.001). Flow cytometry demonstrated that LA were predominantly monocytes. Leukocyte aggregates were positively associated with plasma levels of fibrinogen (P<0.01), or serum high-sensitive C-reactive protein (P<0.01). Moreover, LA had highly significant associations with brachial-ankle pulse wave velocity (P<0.001) and IMT (P<0.001). In conclusion, we demonstrated hemorheologically that monocyte-platelet conjugates play an important role in aortic stiffness and IMT in HD patients.     

ESR study of radiation-induced polymerization of styrene adsorbed on silica gel

The effect of the specific surface area of silica gels on the radiation-induced polymerization of styrene adsorbed on silica gel was studied by ESR. The same radicals were generated on the silica gels regardless of the specific surface area, but the stability of the radicals at room temperature depended on the specific surface area. This means that the decay of the radicals proceeded mainly on the surface of the silica gel. Almost all the radicals generated by irradiation were initially in the bulk of the silica gel and migrated from the interior to the surface of the gel. When styrene monomer was adsorbed on the surface of the silica gel, the silica gel radicals interacted with the monomer and initiated polymerization and then generated polymer. The rate of migration of the silica gel radical was rather fast in the case of silica gel with a large specific surface area. Thus, the polymerization behavior of styrene adsorbed on silica gel greatly depended on the specific surface area of the gel.     

Electron spin resonance studies of γ-irradiated cellulose. II. Free radicals in accessible regions to water in cellulose I and cellulose II

The types of free radicals produced in the water-accessible regions of cellulose I and cellulose II fibers by γ-irradiation in nitrogen atmosphere at room temperature were studied by ESR spectroscopy. The ESR spectra of the irradiated cellulose I and II change by contacting the fibers with water, and after immersion in water the spectral shape depends on the orientation of the fiber axes to the magnetic field. These spectra are probably related to the free radicals generated in the highly ordered regions inaccessible to water in irradiated cellulosic fibers. The ESR spectrum of free radicals generated in decrystallized cellulose after irradiation consists of a singlet and a doublet. When the ESR spectra of free radicals formed in the highly ordered regions of cellulose I and II and the singlet and the doublet are combined in adequate ratio, the constructed spectra are similar to those of the radicals scavenged by water in the irradiated cellulose I and II fibers. From these facts, the spectra due to the free radicals in the water-accessible regions in irradiated cellulose I and II are considered to consist of the singlet and the doublet formed by free radicals in the typical amorphous regions and the spectra of other types of radicals generated in the semicrystalline regions.