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1.
Endoglucanase production was measured in culture filtrates of four species of Saccobolus growing in media containing glucose or crystalline cellulose as the only carbon sources. Enzyme activity was four to seven times higher in the presence of cellulose than glucose. S. saccoboloides showed maximal growth and enzyme production. The extracellular proteins secreted during growth on cellulose were separated by polyacrylamide gel electrophoresis and stained for proteins. A zymogram technique was used to visualize bands with endoglucanase activity. The four species showed different protein and isoenzyme patterns.  相似文献   
2.
A method to generate a porous region near the surface of a polymer is suggested. In this method the region near the surface is swollen by immersing the polymer for a short time in a solvent. Subsequently, the polymer is introduced in a nonsolvent (for the polymer) that is, however, miscible with the solvent. The formation of the porous region is a result of (1) the swelling accompanied by the disentanglement of the surface molecular chains, and the dissolution of some of them during the immersion in the solvent, and (2) the rapid extraction of the solvent from the swollen region by the nonsolvent. The porous surface provides a matrix into which a second incompatible monomer can be polymerized so that the two otherwise incompatible polymers can adhere to one another.  相似文献   
3.
We have developed a reel-to-reel microchip mounting system that continuously mounts LED chips and other microchips on meter-long flexible printed circuit board (PCB) tape for 1.2-m-long standard LED light tubes. Mounting microchips on meter-long PCBs is difficult because a large chip mounter is expensive and the chip positioning stage is difficult to move in a meter-wide area with an accuracy of hundreds of micrometers. Hence, we developed a new microchip mounting system that utilizes a small chip mounter and reel winding machines. The system repeatedly moves the long PCB tape by a certain length with the reel winding machines and mounts the chips on it. The PCB tape (which is 5 mm wide) is made by fabricating long PCB tapes which are 25 cm × 26.6 m through a roll-to-roll PCB process and slitting them into meter-long tapes. The reel-to-reel system repeatedly mounts chips by adjusting their positions through image processing of the copper wiring pattern on the PCBs. Our constructed system mounted 24 LED chips with a pitch of 5 cm with an accuracy of 0.082 mm to form a 1.2-m-long LED tape. The luminance of the tape is 12.4 lx at a distance of 1 m, which is the luminance of outdoor corridor lighting. Therefore, this system can be used for meter-long tape lighting.  相似文献   
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Safety demonstration tests using the High Temperature Engineering Test Reactor (HTTR) will be conducted for the purpose of demonstrating inherent safety features of High Temperature Gas-cooled Reactors (HTGRs) as well as providing the core and plant transient data for validation of HTGR safety analysis codes. The first phase safety demonstration test items include the reactivity insertion test and the coolant flow reduction test. In the reactivity insertion test, which is the control rod withdrawal test, one pair out of 16 pairs of control rods is withdrawn, simulating a reactivity insertion event. The coolant flow reduction test consists of the partial loss of coolant flow test and the gas circulators trip test. In the partial loss of coolant flow test, primary coolant flow rate is slightly reduced by control system. In the gas circulators trip test one and two out of three gas circulators are run down, simulating coolant flow reduction events. The gas circulators trip tests, in which position of control rods are kept unchanged, are simulation tests of anticipated transients without scram (ATWS).  相似文献   
6.
Treatment of storm-water runoff may be necessary before discharge to surface waters. In urban areas, space constraints limit selection of conventional treatment systems, and alternative systems are needed. This research program involves design and laboratory testing of a small footprint nonproprietary detention basin which consists of pipes and box culvert sections with a specialized inlet and outlet system. This system can be placed below grade near the roadway section as part of the conventional drainage system and does not require additional right-of-way. A mathematical model, based entirely on hydraulic principles, is developed to estimate particle removal efficiency of the rectangular detention basin for the treatment of storm-water runoff by extending ideal horizontal tank theory under the condition in which water level is varied. A physical model was built in 1/5 scale to measure particle removal performance and validates the conceptual model. Experiments were performed for steady inflow conditions with different inflow rates, durations, and suspended sediment concentrations. Measured time series outflow suspended sediment concentrations and particle removal efficiency compare well with calculated results from the conceptual model. The outflow particle-size distribution can also be estimated using the conceptual model.  相似文献   
7.
Infection of pigs with many strains of African Swine Fever Virus (ASFV) has been shown to cause a loss or marked decrease in the ability of splenocytes to respond to mitogens. These observations have been extended by cell fractionation and reconstitution experiments to show that the mitogen stimulated proliferative capacity of both the CD4+ and CD8+ T cells is affected. Similarly, monocytes which are directly infectable by virus, are functionally defective as antigen presenting cells when added to mitogen stimulated normal T cells. Interestingly, the same T cells which respond poorly in mitogenic assays can be activated by stimulation through the CD3 receptor. In contrast to the defective mitogenic response of T cells, B cell function, as assessed by stimulation through the CD40 ligand in vitro remains intact. There is no evidence for apoptosis in either the T cells or the B cells recovered from the spleens of ASFV infected animals 1-5 days following infection. Although the number of leucocytes which can be recovered from the infected spleen decreases rapidly with progression of the disease, the proportion of the different cell phenotypes remains constant. Thus decreased activity of lymphocytes in lymphoid tissue from ASFV infected animals appears to be directly attributable to infection of the monocytes.  相似文献   
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The lipolytic and proteolytic activity of Penicillium camemberti PC TT033 and Penicillium roqueforti PR G3, cultured on the whey solids or simulated cheese media, were compared under several pH reaction conditions. Lipolytic activity was higher when both strains had been cultured on the whey medium than on the simulated cheese medium, whereas proteolytic activity was less influenced by the culture medium. The relationship between the reaction pH and these enzyme activities was dependent on the culture medium, which suggested that the expression level and balance of isozyme rely on the culture substrate.  相似文献   
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