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Up to now, the research studies about 5-aminotetrazole (5-AT) gas generators are still not complete. In this work, ten gas generators based on 5-AT with different ordinary oxidants were designed. At the same time, ten gas generators based on azodicarbonamide (ADC), a current gas-generating material, were also designed, which serves as a contrast to formulas of 5-AT. The oxidants of all formulas are the same in proportion. The specific volume, gas production rate, and combustion temperature of these gas generators were measured and calculated. In conclusion, 5-AT/KClO4/Fe2O3/MnO2 formula has high specific volume, acceptable combustion temperature (1466.07 K), and large gas production (maximum pressures can reach 1.79 MPa). It is a kind of gas generator with potential value of development such as using in inflating airbags of automobiles. [ABSTRACT FROM AUTHOR]

Land cover type is a crucial parameter that is required for various land surface models that simulate water and carbon cycles, ecosystem dynamics, and climate change. Many land use/land cover maps used in recent years have been derived from field investigations and remote-sensing observations. However, no land cover map that is derived from a single source (such as satellite observation) properly meets the needs of land surface simulation in China. This article presents a decision-fuse method to produce a higher-accuracy land cover map by combining multi-source local data based on the Dempster–Shafer (D–S) evidence theory. A practical evidence generation scheme was used to integrate multi-source land cover classification information. The basic probability values of the input data were obtained from literature reviews and expert knowledge. A Multi-source Integrated Chinese Land Cover (MICLCover) map was generated by combining multi-source land cover/land use classification maps including a 1:1,000,000 vegetation map, a 1:100,000 land use map for the year 2000, a 1:1,000,000 swamp-wetland map, a glacier map, and a Moderate-Resolution Imaging Spectroradiometer land cover map for China in 2001 (MODIS2001). The merit of this new map is that it uses a common classification system (the International Geosphere-Biosphere Programme (IGBP) land cover classification system), and it has a unified 1 km resolution. The accuracy of the new map was validated by a hybrid procedure. The validation results show great improvement in accuracy for the MICLCover map. The local-scale visual comparison validations for three regions show that the MICLCover map provides more spatial details on land cover at the local scale compared with other popular land cover products. The improvement in accuracy is true for all classes but particularly for cropland, urban, glacier, wetland, and water body classes. Validation by comparison with the China Forestry Scientific Data Center (CFSDC)–Forest Inventory Data (FID) data shows that overall forest accuracies in five provinces increased to between 42.19% and 88.65% for our MICLCover map, while those of the MODIS2001 map increased between 27.77% and 77.89%. The validation all over China shows that the overall accuracy of the MICLCover map is 71%, which is higher than the accuracies of other land cover maps. This map therefore can be used as an important input for land surface models of China. It has the potential to improve the modeling accuracy of land surface processes as well as to support other aspects of scientific land surface investigations in China. [ABSTRACT FROM AUTHOR]

This article presents a numerical method directed towards the simulation of flows with changes of phase. The volume-of-fluid level set (VOSET) method, which is a new interface capturing method and combines the advantages of both volume-of-fluid (VOF) and level set methods, is used for interface tracking. A difficulty occurs for the problems studied here: the discontinuous velocity field due to the difference between mass-weighted velocity and volume weighted velocity caused by the phase change at the interface. In this article, some special treatment is made to overcome this difficulty. The VOSET method and the developed treatment for the difference between mass-weighted and volume-weighted velocities are adopted to simulate a one-dimensional Stefan problem, two-dimensional horizontal film boiling, and horizontal film boiling of water at near critical pressure. The predicted results in both Nusselt number and flow patterns are agreeable with experimental results available in the literature. [ABSTRACT FROM AUTHOR]

In this work, the (R)‐N,N,N‐trimethyl‐2‐aminobutanol‐bis(trifluoromethanesulfon)imidate chiral ionic liquid was first used in chromatography and exhibited a excellent chiral recognition ability in high performance capillary electrophoresis (HPCE), high performance liquid chromatography (HPLC), and capillary gas chromatography (CGC), which also showed for the first time that chrial ionic liquid was an effective chiral selector in HPCE and HPLC. The compounds that have been separated using this chiral ionic liquid at least included alcohol, amine, acid, and amino acid, et al. enantiomers. As the chiral ionic liquid can be easily synthesized from relatively inexpensive materials, it should have a great potentiality for chiral separation in chromatographic science. [ABSTRACT FROM AUTHOR]

High-speed countercurrent chromatography was used for the prefractionation of flavonoids from the crude extracts of Pericarpium citri reticulatae, Radix puerariae, Radix glycyrrhizae, Radix scutellariae, and Flos genkwa. All separations were performed only with a two-phase system composed of CHCl3 : CH3OH :H2O=4 : x : 2. The x was changed for each sample between 2.5∼4.5. The fractionated components were identified by thin-layer chromatography, which confirmed this solvent system was versatile and very useful for prefractionation of flavonoids. [ABSTRACT FROM AUTHOR]

In order to find a high-speed countercurrent chromatography solvent system that can be used as a general prefractionation step for anthraquinone, the crude extracts of five traditional Chinese medicines, Radix rubiae, Rhizoma polygoni cuspidati, Semen cassiae, Radix et rhizoma rhei, and Aloe were separated with a two-phase system composed of CHCl3:CH3OH:H2O = 4:x:2 in which x was between 3 and 4 for different samples. The fractionated components were identified on TLC. This solvent system gave a good separation in most of the anthraquinones. [ABSTRACT FROM AUTHOR]

Presents a study which described the development of a method of capturing, processing and analyzing images of spark paths in air in three dimensions. Description of photographs of sparks; Technique used to investigate various aspects of spark breakdown in point-plane electrode systems; Composition of the electrode system for the short sparks; Results in the recording of three images.