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51.
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Gossypol has been identified as a component of bract (FDB) from frost-killed, field-grown cotton by its chromatographic behavior
on films of silica and cellulose (four eluents and five methods of detection). In addition, a derivative of gossypol was detected,
and it was shown chromatographically that gossypol was removed from extracts of FDB by a divalent metal and by aniline. The
total gossypol content, by spectrophotometric determination of gossypol-aniline complex, of FDB was 0.93%, but for a sample
of bract from a cotton plant that had been grown in a hothouse it was only 0.048%. However the free gossypol contents in both
were similar (0.065% and 0.044%, respectively). Both bract samples were from glanded cotton varieties. It is worthwhile to
investigate the effect of gossypol on lung tissue to see if it can contribute to the acute response of byssinosis. In addition,
it is noted that the waste from ginned cotton which is sometimes used as livestock feed may contain gossypol. 相似文献
53.
Studenovská H Slouf M Rypácek F 《Journal of materials science. Materials in medicine》2008,19(2):615-621
The technique for fabrication of soft porous hydrogels, in which both the size and the orientation of inner pores can be controlled,
was developed. Three-dimensional hydrophilic gels based on poly[2-hydroxyethyl methacrylate] are designed as scaffolds for
regeneration of soft tissues, e.g., nerve tissue. Anisotropic macropores of the size ranging from 10 to 50 μm were formed
(1) by using a porogen-leaching method with a solid organic porogen, (2) by phase-separation during gelation in solvent-nonsolvent
mixture, or (3) by combination of solid porogen elimination and phase-separation. As a porogen, poly(l-lactide) fibers were applied and consequently washed away under mild conditions to obtain desired spatial orientation of
pores. Highly water-swollen polymer gels were characterized with high pressure (low vacuum) scanning electron microscopy (AquaSEM).
The morphology of voids remaining after removing the solid PLLA porogen (the macropores) was clearly shown. 相似文献
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Hana Sebestova Martina Havelkova Hana Chmelickova 《Metallurgical and Materials Transactions B》2014,45(3):1116-1121
The finite-element tool SYSWELD (ESI Group, Paris, France) was adapted to simulate pulsed-laser seam welding. Besides temperature field distribution, one of the possible outputs of the welding simulation is the amount of absorbed power necessary to melt the required material volume including energy losses. Comparing absorbed or melting energy with applied laser energy, welding efficiencies can be calculated. This article presents achieved results of welding efficiency estimation based on the assimilation both experimental and simulation output data of the pulsed Nd:YAG laser bead on plate welding of 0.6-mm-thick AISI 304 stainless steel sheets using different beam powers. 相似文献
59.
Gunuk Wang Hana Yoo Seok-In Na Tae-Wook Kim Byungjin Cho Dong-Yu Kim Takhee Lee 《Thin solid films》2009,518(2):824-18136
We fabricated and characterized a large number of octanedithiol (denoted as DC8) molecular devices as vertical metal–molecule–metal structure with or without using an intermediate conducting polymer layer of poly (3,4-ethylenedioxythiophene) stabilized with poly(4-styenesulfonic acid) (called as PEDOT:PSS). The electronic transport properties of DC8 molecular devices with and without PEDOT:PSS layer were statistically compared in terms of current density and device yield. The yields of the working molecular devices were found to be ~ 1.75% (84 out of 4800 devices) for Au/DC8/Au junctions and ~ 58% (74 out of 128 devices) for Au–DC8/PEDOT:PSS/Au junctions. The tunneling decay constants were obtained with the Simmons tunneling model and a multibarrier tunneling model for two kinds of molecular devices with and without PEDOT:PSS layer. 相似文献
60.
Javorská H Tlustos P Komárek M Lestan D Kaliszová R Száková J 《Journal of hazardous materials》2009,161(2-3):1202-1207
The objectives of this study were to investigate the effectiveness of ozone treatment on degradation of polychlorinated biphenyl (PCB) contaminated soils and to observe the subsequent changes in soil physico-chemical properties. Furthermore, the ability of plants to grow on the ozone-treated soils was evaluated. Soils with different physico-chemical characteristics spiked with seven PCB congeners in two different time periods were chosen. Ozonation was more efficient for PCB degradation in freshly spiked soils and the removal efficiency increased with increasing ozonation time. The highest decrease was found in the soil with a lower soil organic matter (SOM) content and a coarser soil structure indicating the substantial effect of soil characteristics on the efficiency of ozonation. The composition of individual PCB congeners changed in all treatments in terms of higher accumulation rate of highly chlorinated biphenyls with a higher ozonation time. Increased mobility of several elements, changes in SOM content and in soil pH were detected after ozonation. Vulnerability of plants to these modifications was documented on rape seedlings. No inhibition in growth during any treatment and predominantly higher concentration of PCB in non-ozonated treatments were observed. Results suggest that this method can present a promising environmental friendly remediation technology for PCB contaminated soils. 相似文献