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The temporal and spatial accuracy of precipitation of ensemble numerical forecast systems is an important factor that affects the level of meteorological and hydrological coupled forecasting. This article focuses on the current research of verification of precipitation accuracy and statistical post-processing. The verification of forecast precipitation accuracy mainly focuses on the probabilistic characteristics such deterministic accuracy, the resolution, the forecasting skills and the degree of dispersion. Some mainstream statistical post-processing methods have strong performance of spatial downscaling and error correction, but they commonly have the defect of destroying the temporal and spatial dependent structure of precipitation. A comprehensive statistical post-processing method integrated the three functions is the development direction in the future. At the same time, statistical post-processing methods to improve the certainty and probabilistic accuracy of forecast precipitation need to be systematically identified. Its impact on the spatio-temporal dependence structure also needs to be improved.

Atom- and step-economic oxo-azidation and oxo-hydroxyphthalimidation of styrenes have been developed under mild electrolytic conditions, respectively. Various valuable alpha-azido or hydroxyphthalimide aromatic ketones were synthesized efficiently from readily available styrenes, azides, and N-hydroxyphthalimides. Mechanism studies show that two different pathways involved in these two transformations.

Cokes were produced in an electrical furnace from a coal blend containing varying levels of added TiO2. The effects of TiO2 levels on coke structure and properties were then considered. Mercury int...

Coke is the main material of blast furnace (BF), and its reaction speed has an important influence on BF smooth operation. The coke reactivity is mainly affected by coke structure and mineral catalysis. The objective of the present work is to expand the catalytic mechanism of alkali carbonates on coke gasification reaction. Thermogravimetric equipment was used to carry out the non-isothermal analysis experiment and the isothermal analysis experiment. The software (FactSage 6.2) was used to carry out the thermodynamic calculation for gasification of alkali carbonates. Then, the interaction of surface activated oxygen species of C6 clusters and alkali carbonates, the adsorption, and subsequent desorption behaviors of CO2 on the oxygen vacant surface of Na2O and K2O were systematically studied by using the first-principle method based on density functional theory. The reaction path of carbon–oxygen catalytic gasification was theoretically analyzed to explain the reaction mechanism of catalytic gasification.

Four Chinese bituminous coals were analyzed using X-ray diffraction, Fourier-transform infrared spectroscopy and X-ray photoelectron spectroscopy, and the relationships between structural parameters and coal rank were then established. X-ray diffraction analysis reveals that amorphous and crystalline carbon types exist in coals, and average stacking heights and lateral sizes of the layer structures are various. Good correlations between coal crystalline volume, aromaticity and maximum vitrinite reflectance exist, reflecting their level of maturity. The Fourier-transform infrared spectroscopy analysis shows that A-factor, reflecting the coal hydrocarbon-generating potential, decreases with the increase of maximum vitrinite reflectance. Meanwhile, small values of C-factor and C=O/C=C show little amount of C=O components in coal samples. A good correlation between CH2/CH3 and R0 indicates that the length of aliphatic chains declines with the increase of coal rank. X-ray photoelectron spectroscopy analysis shows that the relative amounts of C–C and C–O groups rise with the increase of R0 value. The higher the R0 is, the lower the amount of C vacancy exists, which results in coal reactivity decreasing, all of which suggest that the variety of coal structure mainly depends on the coal rank.

Co-pyrolysis of biomass and coal was investigated as an effective way to reduce the greenhouse gas emission. The effects of poplar on the thermal behavior of fat coal were studied using thermogravimetric analyzer. The blended samples heated to characteristic temperature were subjected to attenuated total reflection Fourier transform infrared spectroscopy (ATR-FTIR) to characterize the macromolecular structure. The results indicated that the synergistic effects existed in co-pyrolysis process of blends since lower char yield than calculated values, and the synergistic effects presented positive and negative trend with the increase of temperature, respectively. The carbonyl/carboxyl C=O stretching vibration functional groups and aliphatic side chain from individual fuels were decomposed in advance during co-pyrolysis. Furthermore, the hydrocarbon-generating potential (A-factor) and thermal maturity(C-factor) of the mixtures showed nonadditivity performance.

Objectives: To investigate the protective effect of recombinant mouse β-defensin 3 (rMBD3) against coxsackievirus B3 (CVB3)-induced myocarditis in mice. Methods: CVB3-infected HeLa cells were treated with rMBD3, and the titer of CVB3 and the proliferative activities of the cells were determined. CBV3-infected BALB/c mice were divided into five groups: rMBD3 high (5 mg/kg/day, q.d.), rMBD3 low (2.5 mg/kg/day, q.d.), ribavirin (10 mg/kg/day, q.d.), normal control, and myocarditis control. On days 5 and 12 after treatment, 3 mice from each group were sacrificed and serum lactate dehydrogenase, creatine kinase-MB isozyme, and tumor necrosis factor-α levels were determined. The heart index and the inflammation of myocardial tissue were also assessed. On day 5, the CVB3 50% tissue culture infective dose (TCID50) values of heart tissues were measured. Results: rMBD3 inhibited the replication of CVB3 and protected HeLa cells from infection. rMBD3 reduced the CVB3 titer markedly and inhibited the pathological reaction of cardiac myocytes to viral myocarditis. Treatment with rMBD3 improved the cell survival rate and reduced the cardiac index. Conclusion: rMBD3 was demonstrated to possess anti-CVB3 activity in vivo and in vitro.

Chitosan/Prussian blue (PB) based biosensors, including a glucose sensor, a glutamate sensor and a galactose sensor have been developed. The biosensors exhibit excellent performance; in particular, the interference of ascorbic and uric acids can be avoided due to selective permeability of chitosan film and electro-catalysis of the PB layer to H2O2. The biosensors have been applied to detect glucose, galactose and glutamate in human blood serum and fermented solution.

A surface MEMS miniature switch with the cantilevered arm has been made on low resistivity Si substrate. The switch was inserted into a time domain setup and their lifetimes have been characterized as a function of actuated voltage, demonstrating some relationship among lifetime and threshold voltage. The structure of MEMS RF switch is simulated by ANSYS software, doing some failure analysis and discussing difference comparing the experiment.© (2004) COPYRIGHT SPIE--The International Society for Optical Engineering. Downloading of the abstract is permitted for personal use only.