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91.
92.
This paper describes a fundamental study on a pneumatic particle trap with a vibrator matrix. The particle trap device consisted of pneumatic vibrators and a trap chamber used to trap a particle. The entire structure was fabricated from polydimethylsiloxane (PDMS). The particle in the trap chamber was manipulated and trapped in the equilibrium region by exploiting the geometrical symmetry of the vibrators. The x-axial velocity of the viscous fluid induced by the deformation of the flexible diaphragms was eliminated or minimized at the center of two vibrators. Therefore, a particle could be trapped in the central capturing region by two or four vibrators. The trapping of static and dynamic single particles was observed to verify the proposed operational method.  相似文献   
93.
A 200-MHz double-data-rate synchronous-DRAM (DDR-SDRAM) was developed. The chip contains a delay-locked loop (DLL) which performs over a wide range of operating conditions. Post-mold-tuning allows precise replica programming. A 200-MHz intra-chip data bus is suitable for DDR operation  相似文献   
94.
We analyzed the dietary fish and marine mammal oil supplements purchased from Japanese markets for hexabromocyclododecane (HBCD); 20 brands were analyzed by liquid chromatography–tandem mass spectrometry (LC/MS/MS). HBCD was detected in 15 of 22 samples, and the concentrations of all the HBCD isomers (α, β, and γ) ranged from <0.9 to 67 ng/g lipid weight. α-HBCD was the dominant residue among the HBCD isomers. However, the composition of HBCD isomers varied according to the sample type. We found that 1 sardine oil brand and 2 shark liver oil brands extracted from fish captured in seawater around Japan contained relatively high levels of HBCD, indicating that both the surface and deep seawaters around Japan may have been contaminated with HBCD.  相似文献   
95.
One thousand two hundred cycles of accelerated exposure experiment with combined salt water spray simulating atmospheric corrosion was performed for investigating the effect of weld line direction and paint orientation on the corrosion and paint deterioration characteristics of welded part of the steel. The corrosion depth of the weld toe of transverse weld line became 1.35 times as large as that of the base metal part because of the remained salt water on the weld toe. The coating thickness at the weld toe became thin by vertically painting on the transverse weld line. When the scribe line was installed at the thin painted weld toe under the transverse weld line, the paint blister area became 15% larger than that of the base metal part. The paint coating thickness at the weld toe in different weld line directions and paint orientations should be confirmed and ensured from the viewpoints of manufacturing and maintaining steel structures.  相似文献   
96.
Accumulating data indicates that certain microRNAs (miRNAs or miRs) are differently expressed in samples of tumors and paired non-tumorous samples taken from the same patients with colorectal tumors. We examined the expression of onco-related miRNAs in 131 sporadic exophytic adenomas or early cancers and in 52 sporadic flat elevated adenomas or early cancers to clarify the relationship between the expression of the miRNAs and the endoscopic morphological appearance of the colorectal tumors. The expression levels of miR-143, -145, and -34a were significantly reduced in most of the exophytic tumors compared with those in the flat elevated ones. In type 2 cancers, the miRNA expression profile was very similar to that of the exophytic tumors. The expression levels of miR-7 and -21 were significantly up-regulated in some flat elevated adenomas compared with those in exophytic adenomas. In contrast, in most of the miR-143 and -145 down-regulated cases of the adenoma-carcinoma sequence and in some of the de novo types of carcinoma, the up-regulation of oncogenic miR-7 and/or -21 contributed to the triggering mechanism leading to the carcinogenetic process. These findings indicated that the expression of onco-related miRNA was associated with the morphological appearance of colorectal tumors.  相似文献   
97.
Effects of the clumping of bacterial spores on their heat resistance as a result of heat treatment were investigated. Spore suspensions of Bacillus cereus, Bacillus coagulans and Bacillus licheniformis were heated at 85 degrees C. Survivor curves of the three strains showed tailing in all treatments after 30 min. As the treatment time increased, the formation of spore clumps increased in all strains after 20 min. Relative hydrophobicity of the spore surface increased as a result of heat treatment. The effect of spore concentration on the inactivation of the B. licheniformis spores was investigated, and surviving curves showed no tailing below a concentration of 4.9 log CFU/ml.  相似文献   
98.
Rhodococcus jostii RHA1 accumulates chlorobenzoates (CBA) during the degradation of polychlorinated biphenyls (PCBs). CBA degradation is considered one of the rate-limiting steps in the complete degradation of PCBs. To reduce the accumulation of CBAs, the upper pathway enzyme genes for PCB degradation of RHA1 were introduced into a CBA-degrading bacterium, Burkholderia sp. NK8. The resulting recombinant strain exhibited no biphenyl 2,3-dioxygenase (BphA) activity encoded by bphAaAbAcAd genes, which encode the large and small subunits of the terminal oxygenase component and the ferredoxin and reductase subunits responsible for electron transfer from NADH to the large subunit. The remaining enzyme genes involved in the transformation of biphenyl to benzoate, bphB2C1D1, which encode dehydrogenase, ring-cleavage dioxygenase and hydrolase, conferred activities to NK8. To obtain the BphA activity of RHA1 in NK8, sets of BphA genes were constructed by combining the bphAaAbAcAd genes of RHA1 and bphA3A4 of Pseudomonas pseudoalcaligenes KF707, encoding the ferredoxin and reductase subunits. Hybrid derivatives of BphA containing the KF707 bphA3 conferred BphA activity to NK8, and a derivative containing the RHA1 bphAaAb and KF707 bphA3A4 genes exhibited the highest BphA activity. A plasmid containing the RHA1 bphAaAb and KF707 bphA3A4 genes plus the RHA1 bphB2C1D1 genes was constructed and introduced into NK8. The resulting recombinant strain efficiently degraded 2-, 3- and 4-chlorobiphenyls with an apparent reduction in CBA accumulation in comparison to the recombinant mutant strain, which had an insertion in the cbeA gene to inactivate CBA dioxygenase.  相似文献   
99.
We have developed an incentive‐rewarding mechanism that stimulates activities in social networking services (SNSs), including content uploading and link establishment. We particularly focus on changing the reward assignment ratio based on the different risks users perceive when uploading content with different privacy settings: public‐open and friend‐limited. Learning‐based simulation allowed us to observe that SNS activity, which we measured as the amount of browsed content within a certain period, can be controlled by a rewarding assignment ratio. We then analyzed how the amount of uploaded content and the increase of established links affect SNS activity. Results suggested that the optimal reward assignment ratio to maximize SNS activity changes depending on the total amount of available reward resources. Copyright © 2011 John Wiley & Sons, Ltd.  相似文献   
100.
A new three-phase current-fed soft-switching PWM converter is presented. This converter utilises two types of switching commutation scheme to improve the PWM current utilisation rate. It is shown by means of computer simulation that this converter has low THD and offers unity power factor correction  相似文献   
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