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1.
Multimedia Tools and Applications - With the development of technology, the importance of the research on speech emotion recognition and semantic analysis has increased. The research is primarily...  相似文献   
2.
Journal of Materials Science: Materials in Electronics - Five polyethylene glycol (PEG)-based compounds with varying terminal functional groups were investigated as suppressors to investigate the...  相似文献   
3.
C.L. Yeh  G.T. Liou 《Ceramics International》2018,44(16):19486-19491
Fabrication of alumina-chromium carbide composites was investigated by PTFE-activated Cr2O3/Al/C combustion synthesis. PTFE was employed as not only a reaction promoter, but a carburizing agent. Three reaction systems were prepared with different contents of carbon for the synthesis of Cr23C6, Cr7C3, and Cr3C2. The amounts of PTFE were selected to ensure combustion synthesis in the SHS (self-propagating high-temperature synthesis) mode and to provide carbon in quantities of 15 and 25?mol% of the total carbon. Experimental results showed that the combustion wave velocity and temperature decreased with increasing carbon, but increased with PTFE. A correlation between combustion wave velocity and temperature contributed to determination of the activation energy Ea =?89.15?kJ/mol for the combustion reaction. The increase of PTFE also improved formation of chromium carbides. As a result, the Cr23C6– and Cr7C3–Al2O3 composites were produced with almost no impurities. Due to a loss of carbon in carbothermic reduction, the Cr3C2–Al2O3 composite was obtained with Cr7C3 as the secondary carbide. SEM micrographs and DES analyses indicated that spherical carbide grains with a size of 0.5–3.0 μm were synthesized.  相似文献   
4.
The oxygen transmission rate, average volume of free‐volume cavities (Vf) and fractional free volume (Fv) of polyamide 6,10 (PA610)/poly(vinyl alcohol) (PVA) (i.e. PA610xPVA05y, PA610xPVA08y and PA610xPVA14y) blend films reduced to minimum values when their PVA contents reached corresponding optimal values. Oxygen transmission rate, Vf and Fv values obtained for optimal PA610xPVAzy blown films were reduced considerably with decreasing PVA degrees of polymerization. The oxygen transmission rate of the optimal bio‐based PA61080PVA0520 blown film was only 2.4 cm3 (m2·day·atm)?1, which is about the same as that of the most often used high‐barrier polymer, ethylene–vinyl alcohol copolymer. Experimental findings from dynamic mechanical analysis, differential scanning calorimetry, wide‐angle X‐ray diffraction and Fourier transform infrared spectroscopy of the PA610xPVAzy blends indicate that PA610 and PVA in the blends are miscible to some extent at the molecular level when the PVA contents are less than or equal to the corresponding optimal values. The considerably enhanced oxygen barrier properties of the PA610xPVAzy blend films with optimized compositions are attributed to the significantly reduced local free‐volume characteristics. © 2017 Society of Chemical Industry  相似文献   
5.
The 2-oxoglutarate-dependent hypoxia inducible factor prolyl hydroxylases (PHDs) are targets for treatment of a variety of diseases including anaemia. One PHD inhibitor is approved for use for the treatment of renal anaemia and others are in late stage clinical trials. The number of reported templates for PHD inhibition is limited. We report structure–activity relationship and crystallographic studies on a promising class of 4-hydroxypyrimidine-containing PHD inhibitors.  相似文献   
6.
There is a growing concern over the food safety issue related to increased incidence of cooking oil adulteration with recycled cooking oil (RCO). The objective of this study was to detect fresh palm olein (FPO) adulteration with RCO using fatty acid composition (FAC) and Fourier-transform infrared spectroscopy (FTIR) spectral analyses combined with chemometrics. RCO prepared in the laboratory was mixed with FPO in the proportion ranged from 1% to 50% (v/v) to obtain the adulterated oil samples (AO). FACs for FPO, RCO, and AO were determined using gas chromatography equipped with a flame ionization detector (GC-FID). The compositions of most fatty acids in RCO lied within the normal ranges of Codex standard, except for C8:0, C10:0, C11:0, C15:0, trans C18:1, and polyunsaturated fatty acids (PUFAs), C20:5. PUFAs showed a consistent decreasing trend with increasing magnitude of change with respect to increasing adulteration level and thus might be a good indicator for detecting FPO adulteration with RCO. The evaluation parameters (coefficient of determination, root mean standard error) of the FTIR-partial least square (PLS) model of palm oil adulteration with recycled oil are R2 = 0.995 and 3.25, respectively. For FTIR spectral analysis, the distinct variations in spectral regions and aberrations in characteristic bands between FPO and RCO were observed. The optimized PLS calibration model developed from normal spectral of the combined region at 3602–3398, 3016–2642, and 1845–650 cm?1 overpredict the adulteration level. On the other hand, the discriminant analysis classification model was able to classify the FPO and AO into two distinct groups. Improvement of the principles of combined techniques in authenticating AO from fresh oil is beneficial as a guideline to detect adulteration in cooking oil.  相似文献   
7.
Provincial variation of urbanization and urban primacy in China   总被引:7,自引:0,他引:7  
Compared to other developing countries, China has a low urbanization level as a result of government policy to control urban development since 1949. However, there is much regional variation in urbanization and urban primacy among its 26 provinces. This paper attempts to analyze the provincial variation in urbanization and urban primacy of China in 1978 by factor analysis and regression techniques. In China, government policy does not only slow down the overall rate of urbanization but also has profound influence on provincial variation in urbanization and urban primacy. Low urban primacy in the eastern provinces is mainly the result of the urbanization policy of controlling the development of large cities that favours the development of small and medium cities. The spatial industrial policy of decentralizing industries from the coastal provinces to interior provinces encouraged high urbanization and urban primacy in the western interior provinces of China.This paper was developed while Xueqiang Xu was a Visiting Scholar of the Centre of Urban Studies and Urban Planning in 1982–83.  相似文献   
8.
The publication of the Brundtland Report in 1987 has led to worldwide concern over sustainable development. Sustainable development is particularly important to regions that are undergoing rapid economic development, such as the Pearl River Delta and other rapidly developing regions in China, Malaysia, Thailand and Asia. Geographical information systems (GIS) and remote sensing are useful tools in the formulation, implementation and monitoring of urban development in the move towards a sustainable development strategy. Since the adoption of economic reform in China in 1978, cities in the Pearl River Delta are developing very rapidly. Economic growth is around 20% a year, making it one of the highest growth areas in the world. Accompanying economic development is rapid urban growth. This paper attempts to demonstrate the application of the integration of GIS and remote sensing in urban growth management in the Pearl River Delta by using them to monitor and evaluate land development. Remote sensing techniques are used to carry out land‐use change detection by using multi‐temporal remote sensing data. Land‐use change impact analysis is further carried out by the integration of GIS and remote sensing.  相似文献   
9.
This paper aims to study the political incentives of government officials to cooperate with one another to achieve a common goal through game theory. Game theory is often used to analyze and explain regional cooperation by regarding it as a type of institutional collective action in which the actions of its participants (local governments or nations) greatly depend on those of the other participants. However, considering China’s political structure, the political relationship among local government key officials may also influence regional cooperation. This study used the Pan-Pearl River Delta (Pan-PRD) Cooperation, the largest regional cooperation bloc in China formed in 2004. The Pan-PRD covered nine provinces in Mainland China and two special administrative regions as a case study for this research; three models were constructed using game theory to analyze the political incentives of the provincial officials in cooperating with one another under the assumption of relative gains. Results showed that the cooperation incentives are sensitive to the variations of political rankings among the leading provincial officials. Driven by promotion incentives, cooperation is more feasible between jurisdictions with different political rankings and less feasible between jurisdictions with the same political rankings.  相似文献   
10.
Daily intake of TBT, Cu, Zn, Cd and As for fishermen in Taiwan   总被引:7,自引:0,他引:7  
The consumption of contaminated seafood has been reported as an important route of human exposure to metals in Taiwan. We consider the concentrations of TBT, Cu, Zn, Cd, As, and the consumption of oysters of Taiwanese to be the important information related to public health in Taiwan. Therefore, the aim of this study was to evaluate the public health risks associated with TBT, Cu, Zn, Cd and As from shellfish for the general population and fishermen of Taiwan. In general, TBT concentrations in various oysters ranging from 0.32 to 1.51 microg/g dry wt. varied with sampling locations. The highest TBT, Cu, and Zn geometric mean (GM) concentrations in oysters of 1.51, 1180 and 1567 microg/g dry wt. were obtained from the Hsiangshan coastal area. The values of oyster consumption for fishermen were 94.1 and 250 g/day for typically and maximally exposed individuals, respectively. In particular, the highest intake (250 g/day) from fishermen was almost two times greater than that of the general population (139 g/day). The THQ (target hazard quotient) values of Hsiangshan's fishermen are 3.87 and 20.50 for TBT and Cu for maximally exposed individuals are higher than other oyster culture areas. It is interesting that those consuming oysters from Hsiangshan, Lukang, Taishi caused abnormally high THQs of TBT and other metals (100% over 1.0), and TBT was attributed to only 3-21% of the total THQs in different fishermen of Taiwan. Our results suggest that current environmental levels of TBT and other metals are associated with a significant potential threat to human health for fishermen resident in coastal areas of Taiwan.  相似文献   
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