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1.
Anatase-TiO2 cylindrical pellets were microwave sintered and partially transformed to rutile-TiO2.The rutile concentration profile was determined as a function of location within the pellet. The rutile distribution in the microwavesintered pellets was different from that in pellets sintered by conventional fast firing. Temperature profiles within the pellets were estimated using the irreversible nature of the anatase-rutile transformation. The estimated temperature profile within each pellet was not uniform. In the axial direction, maximum temperature occurred in the middle of the pellet. In the radial direction, maximum temperature occurred at 1 mm below the surface of the cylinder wall. Analysis of the temperature profile indicated that, although heat flow occurred in the microwave-sintered pellet, the temperature profile did not change during a microwave exposure of 5–90 min.  相似文献   
2.
This paper introduces the results of measurements made over a period of 14 years after the Seikan Tunnel was opened for service. Because this tunnel is a very long undersea tunnel with the length of 54 km, the necessity of clarifying the long-term behavior of the tunnel structure was recognized from the start. Various measurements are made to survey the condition of the ground and lining concrete and data thus obtained are used to assess the soundness of the tunnel structure. Judging from the data thus far obtained, the tunnel structure appears to remain in a good condition.  相似文献   
3.
An extensive X-ray study of CeO2–Nd2O3 solid solutions was performed, and the densities of solid solutions containing various concentrations of NdO1.5 were measured using several techniques. Solid solutions containing 0–80 mol% NdO1.5 were synthesized by coprecipitation from Ce(NO3)3 and Nd(NO3)3 aqueous solutions, and the coprecipitated samples were sintered at 1400°C. A fluorite structure was observed for CeO2–NdO1.5 solid solutions with 0–40 mol% NdO1.5, which changed to a rare earth C-type structure at 45–75 mol% NdO1.5. The change in the lattice parameters of CeO2–NdO1.5 solid solutions, when plotted with respect to the NdO1.5 concentration, showed that the lattice parameters followed Vegard's law in both the fluorite and rare earth C-type regions. The maximum solubility limit for NdO1.5 in CeO2 solid solution was approximately 75 mol%. The relationship between the density and the Nd concentration indicated that the defect structure followed the anion vacancy model over the entire range (0–70 mol% NdO1.5) of solid solution.  相似文献   
4.
Responses to physical and psychosocial exposures can be measured using diverse methods, but their reliability, particularly under multiple exposures, is largely unknown. Five classes of methods were used to assess physiological and subjective responses among 24 participants to four combinations of physical and psychosocial exposures while performing two identical sessions of a simulated overhead manufacturing task. As an exploratory analysis, test–retest reliability was quantified using intraclass correlation coefficients (ICC) and coefficients of variation (CV). Discomfort ratings were reliable under less favorable exposures, and ratings of the psychosocial environment were most reliable under favorable social support. Workload ratings were most reliable with high physical exposure and favorable social support, and task performance was reliable overall. EMG and heart rate had relatively low reliability. Slightly less than half of the variables were considered reliable, but reliability depended on exposure conditions.Relevance to industry: The study provides information on the reliability of commonly used exposure measurement methods. The results can guide the selection of physiological and psychological work outcome measurements in future studies and work evaluations.  相似文献   
5.
Post-translational modifications (PTMs) of serine and threonine occur by diverse mechanisms, including phosphorylation, sulfation, and various types of sugar chain modifications, making characterization of the resulting structures very labor-intensive. Moreover, to fully understand the biological functions of PTMs, both the sites of modification and the modified structures must be analyzed. The present work describes a novel, versatile strategy in which the released O-glycan and the formerly glycosylated/phosphorylated peptide are labeled and thus amenable to further study. In this approach, glycopeptides/phosphopeptides are subjected to β-elimination in the presence of pyrazolone derivatives (BEP), which in the same reaction labels the formerly glycosylated/phosphorylated peptide. The reaction is essentially a β-elimination/Michael addition in which a carbon-carbon bond-forming Michael donor rather than a heteroatomic Michael donor is used. The O-glycans released upon BEP are recovered as bis-pyrazolone derivatives, without any detectable side reaction (peeling). Using this technique, the O-glycan profiles of model mucin-type glycoproteins were successfully analyzed. The BEP strategy discriminates between phosphorylated and GlcNAcylated peptides, since cleaved GlcNAc is detectable. In addition, both the released O-glycan and the formerly glycosylated peptide can be selectively labeled by different reagents via a β-elimination reaction performed in the presence of pyrazolone and the thiol Michael donor.  相似文献   
6.
Glycosaminoglycans (GAGs) play important roles in cell adhesion and growth, maintenance of extracellular matrix (ECM) integrity, and signal transduction. To fully understand the biological functions of GAGs, there is a growing need for sensitive, rapid, and quantitative analysis of GAGs. The present work describes a novel analytical technique that enables high throughput cellular/tissue glycosaminoglycomics for all three families of uronic acid-containing GAGs, hyaluronan (HA), chondroitin sulfate (CS)/dermatan sulfate (DS), and heparan sulfate (HS). A one-pot purification and labeling procedure for GAG Δ-disaccharides was established by chemo-selective ligation of disaccharides onto high density hydrazide beads (glycoblotting) and subsequent labeling by fluorescence. The 17 most common disaccharides (eight comprising HS, eight CS/DS, and one comprising HA) could be separated with a single chromatography for the first time by employing a zwitter-ionic type of hydrophilic-interaction chromatography column. These novel analytical techniques were able to precisely characterize the glycosaminoglycome in various cell types including embryonal carcinoma cells and ocular epithelial tissues (cornea, conjunctiva, and limbus).  相似文献   
7.
The distribution of fatty acid species at the (sn-1, 3) position or the (sn-2) position of triacylglycerol (TAG) in natural fats and oils has already been analysed by many researchers and several interesting results have been reported. However, most of these reports only focused on the distribution of fatty acids at the or positions in TAG, and did not take account of the combination of fatty acids in the TAG, i.e., the TAG positional isomers. In this study, the actual ratios of TAG positional isomer pairs, consisting of palmitic acid and highly unsaturated fatty acid (HUFA) such as DHA or EPA, in fish and marine mammals were investigated using a high-performance liquid chromatography/atmospheric pressure chemical ionisation-mass spectrometry (HPLC/APCI-MS) system equipped with tandem jointed non-endcapped polymeric ODS columns. The results show that for combinations of DHA or EPA with two palmitic acids in the TAG of marine mammals, binding was almost all at the α position. In contrast, binding of DHA or EPA was mainly at the β position in fish. The preferred DHA and EPA positions in TAG were the same in the same marine mammal or fish. The binding position tendency of HUFA in TAG positional isomers consisting of two HUFAs and one palmitic acid was the same as that for combinations of one HUFA and two palmitic acids. These results were interpreted as showing that the preferred fatty acid species of sn-glycerol-3-phosphate acyltransferase and 1-acyl-sn-glycerol-3-phosphate acyltransferase in marine mammals are different to those in fish and other animals, or that diacylglycerol acyltransferase in marine mammals favours 1,2-dipalmitoyl-sn-glycerol formed from 1,2-dipalmitoyl-sn-glycerol-3-phosphatidate if HUFA is the reaction substrate.  相似文献   
8.
Gold nanorods showing surface plasmon (SP) bands in the near-IR region are used as bioimaging probes that respond to near-IR light in mice. The SP bands of intravenously injected polyethylene glycol-modified gold nanorods are directly monitored from the mouse abdomen by using a spectrophotometer equipped with an integrating sphere. The absorbance at 900 nm from the gold nanorods immediately increases after injection and reaches a plateau. The injection of phosphatidylcholine-modified gold nanorods also increases the absorbance at 900 nm, but the absorbance decreases single exponentially with a 1.3-min half-life. In vivo spectral changes of gold nanorods depend on the surface characteristics, and can be observed in real time using simple spectroscopic measurements.  相似文献   
9.
A lithium-encapsulated fullerenol Li@C60(OH)18, as an example of a polar solvent-soluble endohedral fullerene derivative, has been synthesized and fully characterized by infrared spectroscopy, nuclear magnetic resonance spectroscopy, UV spectroscopy, electron spin resonance (ESR) spectroscopy, matrix-assisted laser desorption ionization time of flight mass spectrometry (MALDI-TOF-MS), elemental analysis, thermogravimetric analysis, and inductively coupled plasma-atomic emission spectroscopy (ICP-AES), and the particle size was determined using the induced grating (IG) method, and scanning probe microscopy. The encapsulated Li+ was clearly detected by 7Li NMR at very high field in the range −15 to −19 ppm, an intermediate lithium-encapsulated fullerenol was detected by MALDI-TOF-MS, and the molar ratio of lithium-encapsulated fullerenol to empty fullerenol was quantitatively determined to be 12:88 by ICP-AES. The solid-state ESR and particle size measurements using the IG method showed the characteristic anionic behavior with no external counter cations, in what can be called a “cation-encapsulated anion nanoparticle”, revealing the drastic differences between its properties and those of empty C60(OH)16.   相似文献   
10.
Despite high theoretical sensitivity, low-cost manufacture, and compactness potentially amenable to lab-on-a-chip use, practical hurdles have stymied the application of the quartz crystal microbalance (QCM) for aqueous applications such as detection of biomolecular interactions. The chief difficulty lies in achieving a sufficiently stable resonance signal in the presence of even minute fluctuations in hydrostatic pressure. In this work, we present a novel versatile planar sensor chip design (QCM chip) for a microliter-scale on-line biosensor. By sealing the quartz resonator along its edges to a flat, solid support, we provide uniform support for the crystal face not exposed to solvent, greatly decreasing deformation of the crystal resonator under hydrostatic pressure. Furthermore, this cassette design obviates the need for direct handling when exchanging the delicate quartz crystal in the flow cell. A prototype 27-MHz sensor signal exhibited very low noise over a range of flow rates up to 100 microL/min. In contrast, signals obtained from a conventional QCM sensor employing an O-ring-based holder were less stable and deteriorated even further with increasing flow rate. Additional control designs with intermediate amounts of unsupported undersurface yielded intermediate levels of stability, consistent with the interpretation that deformation of the crystal resonator under fluctuating hydraulic pressure is the chief source of noise. As a practical demonstration of the design's high effective sensitivity, we readily detected interaction between myoglobin and surface-bound antibody.  相似文献   
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