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991.
We have developed crosslinked salmon-derived atelocollagen (SC) sponge, which has a denaturation temperature of 47°C. Sixty-four knees of 32 mature rabbits were randomly divided into 4 groups after creating an osteochondral defect in the femoral trochlea. Defects in Groups I, II, and III were filled with the crosslinked SC sponge, the crosslinked porcine collagen (PC) sponge, and the non-crosslinked PC sponge, respectively. In Group IV, defects were left untreated as the control. At 12?weeks after implantation, the histological score showed that Group I was significantly greater than Groups III (P?=?0.0196) and IV (P?=?0.0021). In addition, gene expression of type-2 collagen, aggrecan, and SOX9 was the greatest in Group I at 12?weeks. The fundamental in vivo properties of the crosslinked SC sponge showed that this is a promising biomaterial, specifically as a scaffold for cartilage tissue engineering.  相似文献   
992.
Fouling behaviors in membrane filtration of dilute suspension of polystyrene latex (PSL) were examined under constant‐pressure conditions using diatomaceous ceramic membranes which are semi‐permeable to the PSL. Flux decline behaviors were evaluated in consideration of the effect of the solid permeation through the membrane. The conventional characteristic filtration equation was modified by applying the Kozeny‐Carman equation to the filtrate flow through the membrane pores. In the model, the porosity and specific surface area of the membrane were represented by unique functions of the solid deposit retained in the membrane pores. The variations of the filtration rate and filtrate volume with the filtration time were accurately described based upon the modified characteristic filtration equation. It was revealed that the extent of the membrane blocking per unit deposit load increased with the decrease in the pore size of the membrane and with decreasing pressure, but was little influenced by the suspension concentration. © 2009 American Institute of Chemical Engineers AIChE J, 2010  相似文献   
993.
The aim of this study was the preparation of novel water repellent UV curable materials using acrylic modified melamine (AM) and poly-dimethylsiloxane (PDMS). UV curable acrylic melamines containing silicone segments (SiAMs) were synthesized by condensation of methylolmelamine, 2-hydroxyethyl acrylate, and carbinol-modified PDMS. The SiAM films with a 0.3 wt% PDMS segment that were cured by UV irradiation had higher transparency than that of a blended sample. Examination with a scanning electron microscope revealed that the blend sample has cohesion of the silicone segments, while such a phenomenon was not observed in the composite samples (SiAMs). From these results, it was confirmed that aggregation of the silicone segments was prevented by introducing the silicone segments into the acrylic melamine. By introducing 0.3 wt% of PDMS segments into AM, good water-shedding properties were confirmed, while several of the most attractive features of AM, such as hardness, adhesion, and refractive index, were maintained.  相似文献   
994.
Abstract

Ab initio HF and DFT calculations on C60@Si60 confirmed our previous semiempirical results that the interaction of two fullerene layers brings about extensive modification of the bond parameters, the C-C, Si-Si and Si-C bond distances being close to the respective single bond lengths. However, the present calculations revised the previous HOMO-LUMO picuture and the stability relations among C60@Si60, C60 and Si60 species.  相似文献   
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Tokyo University of Information Sciences (TUIS) receives moderate resolution imaging spectroradiometer (MODIS) data, and provides the processed data to universities and research institutes as part of the academic frontier project. One of the major fields of research using MODIS data is the analysis of changes in the environment. We are currently developing applications to analyze environmental changes. These applications run on our satellite image data analysis system, which is implemented in a parallel distributed system and a database server. When using satellite data, one common problem is the interference of clouds. In order to remove this interference, the standard solution is to create composite data of the same regions during a selected time span, and to patch together data which are not covered by clouds to create a clear image. We introduced a piece-processing algorithm which separates one set of satellite image data into many small pieces of image data, making it quicker and easier to analyze and process the time-series satellite data. In this research, we implemented the pieceprocessing and composite-processing algorithms in order to increase the speed of analysis within the satellite image database. We tested the proposed processing and verified its effectiveness for target applications.  相似文献   
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