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1.
The length of potassium titanate fibers produced by several conventional methods averages 50 μm, with a maximum of 100 μm. Extremely long fibers (most >1000 μm long) were obtained by calcination in N2 gas flowing at 5.2×10-4 m/s.  相似文献   
2.
Because of its high–temperature chemical stability, SiC ceramic is a promising material for high-temperature device applications such as thermoelectric energy converters. However, the electrical conductivity of SiC ceramic is too low for it to be used as a thermoelectric energy converter at the cold junction. Therefore, we propose a SiC-Si functionally gradient material (FGM) in order to improve the electrical conductivity of the SiC ceramic at the cold junction. An SiC rod was fired in a temperature gradient furnace. One end of the SiC rod was maintained at 2473 K and the other end was maintained at 1973 K for 30 min. After firing, the porous SiC edge fired at 1973 K was dipped into molten Si in order to infiltrate molten Si into the porous SiC. The microstructure of the FGM is classified into three regions: the SiC-Si composite material; the porous SiC ceramic; and the densified SiC ceramic. The electrical conductivity, the Seebeck coefficient and the thermal conductivity for each region of SiC-Si FGM was measured at 300 K; a figure of merit was calculated. The figure of merit of the SiC-Si FGM at the cold junction, at room temperature, was 108 times higher than that of a nongradient SiC ceramic.  相似文献   
3.
New biomarkers are needed to further stratify the risk of malignancy in intraductal papillary mucinous neoplasm (IPMN). Although microRNAs (miRNAs) are expected to be stable biomarkers, they can vary owing to a lack of definite internal controls. To identify universal biomarkers for invasive IPMN, we performed miRNA sequencing using tumor-normal paired samples. A total of 19 resected tissues and 13 pancreatic juice samples from 32 IPMN patients were analyzed for miRNA expression by next-generation sequencing with a two-step normalization of miRNA sequence data. The miRNAs involved in IPMN associated with invasive carcinoma were identified from this tissue analysis and further verified with the pancreatic juice samples. From the tumor-normal paired tissue analysis of the expression levels of 2792 miRNAs, 20 upregulated and 17 downregulated miRNAs were identified. In IPMN associated with invasive carcinoma (INV), miR-10a-5p and miR-221-3p were upregulated and miR-148a-3p was downregulated when compared with noninvasive IPMN. When these findings were further validated with pancreatic juice samples, miR-10a-5p was found to be elevated in INV (p = 0.002). Therefore, three differentially expressed miRNAs were identified in tissues with INV, and the expression of miR-10a-5p was also elevated in pancreatic juice samples with INV. MiR-10a-5p is a promising additional biomarker for invasive IPMN.  相似文献   
4.
α-Tocopherol was reacted with methyl linoleateperoxyl radicals at 37°C. The peroxyl radicals were generated by the reaction of methyl linoleate with a free radical initiator, 2,2′-azobis(2,4-dimethylvaleronitrile). The primary products of α-tocopherol with methyl linoleate-peroxyl radicals were isolated by reversephase and normal-phase high performance liquid chromatography (HPLC), and their structures were characterized by ultraviolet (UV), infrared (IR),1H and13C nuclear magnetic resonance (NMR) and mass spectrometry (MS). There were four stereoisomers of methyl 13-(8a-peroxy-α-tocopherone)-9(Z),11(E)-octadecadienoate and four stereoisomers of methyl9-(8a-peroxy-α-tocopherone)-10(E),12(Z)-octadecadienoate.  相似文献   
5.
Recently, the development of efficient and environmentally benign solvents has received great attention to replace current harsh organic solvents. In this context, low-transition-temperature mixtures (LTTMs) have emerged as favorable green solvents for biomass delignification. Palm oil biomass, empty fruit bunch (EFB) was pretreated with commercial l-malic acid and microwave hydrothermally extracted cactus malic acid-derived LTTMs at 60, 80, and 100 °C. The LTTMs applied in this study were derived from malic acid–choline chloride–water and malic acid–monosodium glutamate–water with a molar ratio of 2:4:2 and 3:1:5, respectively. Three first-order reactions were used to express the delignification kinetic model of EFB. The first term was based on the initial stage and assigned as infinite due to the fast rate of delignification which could not be detected. The second and third terms were proportional to bulk and residual delignification stages. A good agreement was obtained between the kinetic model and the experimental data obtained in this study with R2?≥?0.91. The activation energies for the delignification reactions using l-malic acid and cactus malic acid-based LTTMs in the bulk and residual stages were approximated as 36–56 and 19–26 kJ/mol and 34–90 and 47–87 kJ/mol, respectively.  相似文献   
6.
Multiple human pose estimation is an important yet challenging problem. In an operating room (OR) environment, the 3D body poses of surgeons and medical staff can provide important clues for surgical workflow analysis. For that purpose, we propose an algorithm for localizing and recovering body poses of multiple human in an OR environment under a multi-camera setup. Our model builds on 3D Pictorial Structures and 2D body part localization across all camera views, using convolutional neural networks (ConvNets). To evaluate our algorithm, we introduce a dataset captured in a real OR environment. Our dataset is unique, challenging and publicly available with annotated ground truths. Our proposed algorithm yields to promising pose estimation results on this dataset.  相似文献   
7.
We propose a prototype of a facial surgery simulation system for surgical planning and the prediction of facial deformation. We use a physics-based human head model. Our head model has a 3D hierarchical structure that consists of soft tissue and the skull, constructed from the exact 3D CT patient data. Anatomic points measured on X-ray images from both frontal and side views are used to fire the model to the patient's head. The purposes of this research is to analyze the relationship between changes of mandibular position and facial morphology after orthognathic surgery, and to simulate the exact postoperative 3D facial shape. In the experiment, we used our model to predict the facial shape after surgery for patients with mandibular prognathism. Comparing the simulation results and the actual facial images after the surgery shows that the proposed method is practical.  相似文献   
8.
9.
Switching of the luminescence properties of molecular materials in response to mechanical stimulation is of fundamental interest and also has a range of potential applications. Herein, a water‐soluble mechanochromic luminescent pyrene derivative having two hydrophilic dendrons is reported. This pyrene derivative is the first example of a mechanochromic luminescent organic compound that responds to relative humidity. Mechanical stimulation (grinding) of this pyrene derivative in the solid state results in a change of the photoluminescence from yellow to green. Subsequent exposure to water vapor induces recovery of the initial yellow photoluminescence. The color change is reversible through at least ten cycles. It is also demonstrated that this compound can be applied as a mechano‐sensing material in frictional wear testing for grease, owing to its immiscibility in non‐polar solvents and its non‐crystalline behavior. Transmission electron microscope and atomic force microscope observations of samples prepared from dilute aqueous solutions of the pyrene derivative on suitable substrates, together with dynamic light scattering measurements for the compound in aqueous solution, indicate that this amphiphilic dumbbell‐shaped molecule forms micelles in water.  相似文献   
10.
Recently, a great deal of foreign investment has been entered into construction of the social infrastructure of Myanmar. Many construction projects are therefore on-going, and these are especially planned in the Yangon area. While these construction booms are increasing, existing studies on the geotechnical problems in the Yangon area such as problematic soils like soft clays are limited at present. Information on soil properties has also not been shared and has been confined to individual projects. In this paper, the boring and laboratory tests carried out in the Yangon area are selected and focused upon among the tests carried out in Myanmar. Laboratory test results for clay deposits in the Yangon area are analyzed and the differences in soil properties between different sedimentary basins and sub-areas divided by the Tertiary sediment ridge that runs from north to south at the center of Yangon are clarified together with a comparison to the clays found in other countries, which have been previously investigated.  相似文献   
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