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1.
The texture of fibrous calcium hydroxyapatite (Ca10-(PO4)6(OH)2, CaHAP) particles that were prepared by the decomposition of calcium–ethylenediaminetetraacetic acid (calcium–EDTA) chelates at 100°C under various pH conditions (pH values of 5–10) was investigated by various means. Well-crystallized fibrous CaHAPs were produced at pH .6. The stoichiometry of the CaHAPs with a chemical formula of Ca10− x (HPO4) x (PO4)6− x (OH)2− x (H2O) x was improved by increasing the decomposition pH. All the CaHAPs had unit-cell dimensions of a = 0.9436 ± 0.0003 nm and c = 0.6881 ± 0.0006 nm, exhibiting an enlarged a value. The finding of mesoporosity of CaHAPs by nitrogen gas (N2) adsorption measurement indicated that the CaHAPs were produced by an agglomeration of primary particles. Furthermore, the nonstoichiometric CaHAPs that formed at pH 6 developed ultramicropores, which were accessible to water (H2O) molecules but not to N2 molecules, by the elimination of H2O molecules that were adsorbed in interstices of primary particles in less-orderly crystallized CaHAPs and/or by dehydration of HPO42− groups. These findings by gas adsorption techniques could give evidence for the agglomeration mechanism to attain a polycrystalline CaHAP, although they exhibited good crystallinity with large size.  相似文献   
2.
Using the value chain model which provides a process view, this longitudinal case study and simulation modeling analysis of a Canadian third-party logistics (TPL) supply chain provides some empirical support for the enabling role of RFID technology in effecting warehouse process innovation and optimization for the focal TPL firm. However, the findings of our study also reveal the RFID technology implementation costs as the key inhibitor of RFID widespread adoption and usage among suppliers. This, in turn, precluded the focal TPL firm from implementing the best optimum RFID solution to create better business value from the RFID project.  相似文献   
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A histochemical assay for detecting genetically modified (GM) papaya (derived from Line 55-1) is described. GM papaya, currently undergoing a safety assessment in Japan, was developed using a construct that included a beta-glucuronidase (GUS) reporter gene linked to a virus coat protein (CP) gene. Histochemical assay was used to visualize the blue GUS reaction product from transgenic seed embryos. Twelve embryos per fruit were extracted from the papaya seeds using a surgical knife. The embryos were incubated with the substrate 5-bromo-4-chloro-3-indolyl-beta-D-glucuronide (X-Gluc) in a 96-well microtiter plate for 10-15 hours at 37 degrees C. Seventy-five percent of GM papaya embryos should turn blue theoretically. The histochemical assay results were completely consistent with those from a qualitative polymerase chain reaction (PCR) method developed by this laboratory. Furthermore, the method was validated in a five-laboratory study. The method for detection of GM papaya is rapid and simple, and does not require use of specialized equipment.  相似文献   
5.
Hotate  K. Kamatani  O. 《Electronics letters》1989,25(22):1503-1505
Novel reflectometry with millimetre or submillimetre spatial resolution is proposed to evaluate optical components or circuits. The optical coherence is modulated to have a periodic delta-function shape along the optical path, and the backscattering intensity is obtained directly. The experiment demonstrates a resolution of about 10 mm in air with a Fabry-Perot laser diode.<>  相似文献   
6.
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   
7.
In this paper, a novel version of the dual voltage converter is presented with improved voltage regulation and enabling a wide range of voltage control by using self-turn-off devices (power transistors) instead of diodes. Further, this system operates with unity displacement factor. We have obtained the analytical expressions of this circuit. The results are, however, quite complex. We could calculate values of the voltage and current waveforms by using a computer. The calculated values are essentially in agreement with the experimental values. Experimentally, an ideal load characteristic with null voltage regulation was obtained by the conduction angle control for power transistors. Further, a wide range of voltage from 220 V to 39 V was obtained. A disadvantage for this system is the requirement for snubber circuits with a larger value of capacitor in order to suppress the surge voltages at turn-off periods.  相似文献   
8.
The effect of seasonings on the texture of cooked spaghetti was examined by sensory and shearing tests. Spaghetti tossed with sucrose, trehalose, salt, and monosodium glutamate and their mixture retarded deterioration of the firmness of spaghetti strands. To investigate the penetration of water and seasonings, maps of spin–spin relaxation time and their profiles from the center to the surface of a spaghetti strand were acquired by magnetic resonance imaging. The homogenization of moisture distribution in cooked spaghetti during holding was delayed temporarily by salt owing to a back current caused by the gradient of salt content on the surface immediately after tossing. Monosodium glutamate rapidly penetrated into spaghetti strands and caused water T2 decrease possibly owing to the decreased mobility of water molecules in starch gel, whereas the sweeteners hardly altered the T2 maps. Salt and monosodium glutamate are considered to retard more effectively the deterioration of firmness of spaghetti.  相似文献   
9.
The screening of a strain which could perform lignin removal was carried out. Based on taxonomic study the isolated strain (LM‐2) was identified as Penicillium sp. LM‐2 could decolorize 0.6 g dm?3 lignin within 4 days in a shaking culture at 25 °C. The efficiency of decolorization of the lignin was over 80% in the pH range of 4.0–6.0, but was low above pH 6.2. The rise of temperature had a slight adverse effect on the lignin decolorization in the range of 25–35 °C. Lignolytic enzymes such as lignin peroxidase, manganese peroxidase and laccase were not detected in the culture broth or within the fungal cells. The lignin was removed from the high molecular weight fraction mainly by adsorption and accumulation inside the cells. © 2001 Society of Chemical Industry  相似文献   
10.
Norovirus (NV) RNA has rarely been detected in foods despite the use of highly sensitive methods such as RT-PCR and real-time RT-PCR. In the modified method (A3T method) reported previously, a bacterial culture process was introduced into the standard protocol for NV detection to remove some inhibitor(s) present in food ingredients. To confirm the efficiency of the A3T method and to examine NV contamination in bivalve molluscs, we tried to detect NV RNA in bivalve molluscs on the market and in oyster samples associated with foodborne outbreaks by using the standard method and the A3T method. NV RNAs were detected in 20 samples (18.0%) of 111 bivalve molluscs, including oysters, on the market by use of the A3T method, while only one sample (0.9%) was positive according to the standard method. NV RNA was also detected in 10 of 35 oyster samples related to foodborne outbreaks by the A3T method. Those results show that the A3T method is suitable for the detection of NV in bivalve molluscs in general laboratories.  相似文献   
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