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At high frequencies, there is an obvious descending of Fourier spectrum amplitude of ground motion acceleration. This fact could be described by a low0pass filter that is controlled by parameter Kappa (κ). In most regions of the world, there are not sufficient strong ground motion records to evaluate this regional parameter. We try to acquireκvalue from small-earthquake records of the broadband digital seismograph network in North China (36°-43°N, 113°-120°E). Total 1995 records from 28 small earthquakes (Mw=3.5-4.5) recorded at 155 stations of China Earthquake Network during February of 2002 to September of 2012, are analyzed. Theκvalue is acquired from the slope rate of the decay segment of the calculated Fourier spectrum of each record, and the mean value is obtained. The result is analyzed ifκis magnitude, focal depth or distance dependent. For the magnitude-dependence,κvalues of 40 strong ground motion records are also obtained and compared. The result of the paper shows thatκis not magnitude-dependent neither focal depth-dependent. The distance-dependent is not obvious, especially for small earthquake.

Nowadays, a large quantity of cemented carbide is being consumed, and the amount of scrap cemented carbide is increasing year by year. In this paper, crystal morphology, element content and phase structure of the recycled cobalt powder as well as recycled tungsten carbide powder were characterized by SEM, EDS and XRD. Hardness of the prepared W-Co alloy using recycled cobalt powder and recycled tungsten carbide powder as the raw materials was tested by Rockwell apparatus. Through analysis of these results, the existing problems in recycling of scrap cemented carbide emerged. As for recycling of scrap cemented carbide, the research results can provide theoretical basis for improvement of recycling technology and process control technology.

This research used bagasse as raw material, through xylanase biological treatment process, preparative bagasse dissolving pulp. The optimum process conditions of sulfuric acid pre-hydrolysis were as below: Acid dosage 0.10%, 150°C, 90min. After pre-hydrolysis, cellulose content of the raw materials increased 18.45%, and pentosan decreased 14.49%. The fiber quality analysis showed fiber length and width were reduced, the tiny fiber content was decreased after acid pre-hydrolysis; HPLC analysis showed the optimum acid pre-hydrolysis process which can reduce the inevitable cellulose degradation effectively,hemicelluloses were hydrolyzed furthest at the same time; FTIR spectrum analysis showed acid pre-hydrolysis process can dissolve a lot of hemicelluloses.

EGSB anaerobic reactor is used to treat the papermaking wastewater, and this paper explore the law of its quick start, HRT and operation cost. Results showed that, during the 47 days, at the condition of inlet COD concentration 2000mg/l, HRT 8h, ascending velocity 0.8m/h, gas output 3600L/d, the COD removal rate can reach up to 65%, and the operation cost is 0.75Yuan/t.

By small earthquake records from the Gansu broadband digital earthquake network, five regional source and crustal medium parameters, stress drop Δσ, quality factor parameters Q0 and η, geometrical spreading parameters R1 and R2, are inversed for the Lanzhou area. Envelops of Fourier spectra are adopted as the objective function, the values of those parameters are 34.625bars, 95.665, 0.360, 58.188km and 105.650km, respectively. These values are adopted to calculate Fourier amplitude spectra, and complex spectra are formed by combining with random phase spectra. Acceleration time histories can be simulated, and PGAs on different moment magnitude-distance pairs are obtained previously. Compared with several observed strong ground motion data, the result is lower in the case of Mw=5.0, passes through the data in the case of Mw=6.0 and higher than the record of Mw=7.0. It is adopted in regional seismic zonation. Compared with The Zonation Map of Earthquake Ground Motion Parameters in China (GB18306-2001), the result is close to the map when PGA is lower than 0.2g.

In this paper, a health risk model was used to calculate and analyze the water quality monitoring data of the Yangtze River Basin from 2007 to 2009. The data analysis leads to a conclusion that hexavalent chromium is a major health risk factor of those drinking water sources in the Jiangsu section of the Yangtze River basin. Based on the health risk analysis, an environment strategy analysis model and the Dynamic Actor Network Analysis (DANA) software were used to study the optimal strategy on the risk management of chromium contamination of those drinking water sources in the Jiangsu Section of the Yangtze River basin.

With accumulation of secondary metabolites vitamin E as the objective, the effects of six components contents in the culture on vitamin E accumulation in wheat embryo callus was studied and the best combination of six components in medium was determined by test optimum. The results showed that the production of vitamin E in B5 medium was the highest at KNO32700mg/L, MgSO4·7H2O 125mg/L, NAA 6mg/L, CaCl2·2H2O 75mg/L, FeSO4·7H2O 13.9mg/L and sucrose 30.0×103mg/L. Vitamin E accumulation varied obviously with sucrose content in the medium, but the influence of magnesium sulfate was not significant.

In this paper an old mining goaf in Henan province is studied with the application of 3D nonlinear finite element method. The excavation and backfilling construction and water conveyance operation of the canal upper the old mining goaf is analyzed. Simulation results show that after the grouting strengthening, no layers exceed corresponding strength limit under both canal construction and operation conditions, meanwhile the surface movement and the size of the deformation are within the scope of the standard and won’t affect the construction and safety operation of the canal.

This study evaluated the feasibility of the mixed material as matrix of eco-toilet and the temporal change of pH value, T-N, T-P, T-K, organic matter and total reduction rate of dry weight in the compost. The mixed material of beanstalk and sawdust with a volume ratio of 1:1 can be used as reaction matrix of on-site composting-type eco-toilet to improve the microbial treatment of human feces. The human feces and urine could be composted to organic fertilizer rich in elements N, P and K. Change of pH in the toilet was divided two phases: changing phase (7.1-8.8) and stable phase (8.4-8.5). T-N, T-P and T-K contents increased with gradual input of feces and urine. Organic matter content decreased from 82.8% to 71.7% and the total reduction rate of dry weight increased gradually from 62.9% to 92.2%. Compost produced in the toilet could be used as organic fertilizer with the optimal concentration ratios for different plants.

The effect of Na and Si content on vitamin E accumulation in a wheat embryo callus culture was studied. Mathematical models were established to describe the growth kinetics and accumulation of vitamin E for the wheat embryo callus cells. With vitamin E accumulation as the objective, the best combination of Na and Si addition in the medium was selected through an optimum test. The results showed that the optimal production of vitamin E in Gamborg’s B5 medium was at the 0.80 mg/L NaH2PO4•H2O and 0.00%(w/w) H2SiO3. The degree of fit of the kinetics model of vitamin E accumulation was 99.11%, whereas the degree of fit of the kinetics model of cell growth was 98.68%, with a nonlinear relation. The beneficial elements Na and Si affected vitamin E accumulation in the wheat germ callus medium and the influence of Si was more significant than that of Na.

A Pichia pastoris cell-surface display system was constructed using a Flo1p anchor system containing N-terminal flocculation functional domain (874 residues, FS), derived from Saccharomyces cerevisiae. The lipase from Rhizopus oryzae with a pro sequence (ProROL) and green fluorescent protein (GFP) gene were successfully cloned and genetically fused to the anchor system with their C-terminus free. Fluorescence microscope was used to detect the GFP displayed on the recombinant P. pastoris cell surface. The results showed that the yeast surface display system using Flo1p as the anchor protein was successfully constructed, and the activity of ProROL displayed on KM71H reached to 217.15 U/g, much higher than 61.30 U/g reported by Matsumoto. Besides, the yeast surface display system could effectively shorten the fermentation time compared with traditional fermentation.

Intensive electroluminescence (EL) visible to the naked eyes is observed from p–i–n structure light emitting diodes with nanocrystalline Si (nc-Si) film as the luminescent layer. It is found the luminescence intensity increases by 20 times compared with that of nc-Si film without p-i-n structure and the turn-on voltage is sharply reduced. Combined with I-V and TEM analysis, the improved EL is attributed to the enhancement of carrier injection probability of nc-Si inserted in p-i-n structure.

The aim was to develop a nonlinearity model of quantitative analysis of vitamin C content by infrared spectroscopy and provide theoretical basis for nondestructive testing of vitamin C content in drugs. The infrared spectrum of vitamin C was smoothed and noise-eliminated by wavelet transform, which may obtained smooth curve and enhanced spectrum resolution. Absorption peak about 3000cm-1was selected as characteristic absorption peak to set up linearity or nonlinearity model. The result showed that nonlinearity model, correlation coefficient 0.9967, had more nicety than that of linearity model. The result of traditional titration of iodine as reference system, relative deviation of nonlinearity model was 2.75%, but that of linearity model was 28.03%. It was feasible and effective to determine vitamin C content by infrared spectroscopy based on nonlinear modeling.