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941.
942.
GON OK DONG-HWAN KIM JU-SUEP IM SEOK-HYONG LEE HYUNG-SEOK KIM 《Polycyclic Aromatic Compounds》2013,33(2):110-122
This study was carried out from the Gwangan Bridge in Busan, Korea in order to examine the characteristics and the amount of PAHs in runoff from Gwangan Bridge, and the consequential PAH burdens in the ocean. The runoff samples were collected in particulate and dissolved phase, and the ambient air samples were collected in particulate and gaseous phase. In this study, 20 samples were collected from 10 different sites. The concentrations of 16 PAHs, in particulate road surface samples, ranged from 76.71 to 170.98 ng/g, and the dissolved road surface runoff samples ranged from 23.31 to 72.9 ng/L. In ambient air, the PAHs concentration in gaseous phase was higher than the samples in particulate phase. From these results, the amount of annual release of PAHs through runoff into the coast was calculated, and the Toxic Potency Equivalency Factors and Dioxin Toxic Equivalency Factors were applied. The annual release of total PAHs and the carcinogenic PAHs via runoff from Gwangan Bridge to the coast were 14.1 g/yr and 3.13 g/yr, respectively. The PAHs-TPEQ was 0.85 g/yr and the PAH-dioxin TEQ was 0.69 mg/yr. 相似文献
943.
The purpose of this paper is to irriprwe allocation of the the target bits in H.264/AVC rate control.The scheme proposes an enhancement method of the target frame rate based on H.264/AVC bit allocation.The enhancement uses a frame complexion estimation to Improvetheexisting Mean Absolute Difference(MAD)complexity measurement.Bit allocation to each frame is riot just computed by target frame rate but alsoadjusted by a combined frame complexity measure- Using the statistical characteristic,the scheme obtains change of occurrence bit about QP to apply the bit amount QP from the video characteristic and apply it in the estimated bit amount of the current frame.Simulation results show that the proposed rate control scheme achieves time saving of more than 99%over existiing rate control algorithm.Nevertheless,Peak Signal-to-Noise Ration (PSNR)and bit rate were almost the same as the performances. 相似文献
944.
High-efficiency design of a mixed-flow pump has been carried out based on numerical analysis of a three-dimensional viscous flow.For analysis,the Reynolds-averaged Navier-Stokes equations with a shear stress transport turbulence model were discretized by finite-volume approximations.Structured grid system was constructed in the computational domain,which has O-type grids near the blade surfaces and H/J-type grids in other regions.The numerical results were validated with experimental data for the heads and ... 相似文献
945.
946.
By using the quantum teleportation protocol, Alice can send an unknown quantum state (e.g. the polarization of a single photon) to Bob without ever knowing about it. This paper discusses a quantum teleportation experiment in which nonlinear interactions are used for the Bell state measurement. Since the Bell state measurement is based on nonlinear interactions, all four Bell states can be distinguished. Therefore, teleportation of a polarization state can occur with certainty, in principle. Details of the theory and the experimental set-up are discussed. 相似文献
947.
N‐T. NGUYEN D‐Y. KIM H. Y. KIM 《Fatigue & Fracture of Engineering Materials & Structures》2013,36(3):202-216
A continuous damage fracture model, which consists of a fracture criterion and a continuum damage constitutive law was proposed in this paper to calculate formability of sheet metal. In this model, an extension of the McClintock void growth model was selected as the fracture criterion to be incorporated with a coupled damage‐plasticity Gurson‐type constitutive law. Also, by introducing a Lode angle dependent parameter to define the loading asymmetry condition, the shear effect was phenomenologically taken into account. The proposed fracture model was implemented in user defined material subroutines in ABAQUS. The model was calibrated and correlated by the uniaxial tension, shear and notched specimens tests. Application of the fracture criterion for the Limit dome height tests was discussed and the simulation results were compared with the experimental data. 相似文献
948.
Changes in Phytase Activity and Phytate During the Germination of Six Canola Cultivars 总被引:1,自引:0,他引:1
Six canola cultivars were germinated for 8-days and the levels of phytate and phytase activity monitored. Of these, the cultivar Regent exhibited the lowest level of phytate as well as the highest phytase activity. Germination of Regent for up to 2-days resulted in the reduction of phytate from 1.26% to 0.85% without any deleterious changes in the quality or quantity of the oil, based on the negligible levels of free fatty acids produced. 相似文献
949.
Comparative Quality Characteristics of Chymosin Extracts Obtained by Ultrasound Treatment 总被引:8,自引:0,他引:8
An ultrasound method was developed for increased efficiency of chymosin extraction. Ultrasound extraction was carried out with a Tekmar sonic disrupter, and control extraction was by shaking. Use of ultrasound resulted in increase in activity and decrease in nitrogen content, thus increasing the specific activity of chymosin extracts. Proteolytic activity of experimental chymosin was higher at 15 and 20°C, but lower at 35 and 40°C than that of controls. Chymosin extracts obtained by ultrasound treatment were darker, less green, less blue, and more turbid than controls. Ultrasound treatment did not affect activation energies for proteolytic activity, total viable cell counts, or storage stability of chymosin extracts. 相似文献
950.
The effects of cyclic freezing and thawing upon the quality of frozen surimi of two species were studied with respect to sol viscosity, sol rigidity changes during thermal processing and structural failure properties of the cooked gel. A torsion test, used to determine the strength of gels subjected to different thermal histories, revealed that increasing the number of freeze-thaw cycles reduced the strength and deformability of both sand trout and Alaska pollack surimis. Continuous monitoring of sol rigidity during thermal processing showed little changes in thermal transition temperatures caused by freeze-thaw abuse for either surimi but shifts occurred in overall rigidity levels. Particularly dramatic changes were induced in the Alaska pollack rigidity thermogram. The rigidity thermograms of sand trout and Alaska pollack were significantly different, as were their responses to freeze-thaw abuse and low temperature (4°C and 40°C) pretreatments. 相似文献