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111.
112.
Microbiological denitrification of red beet juice 总被引:1,自引:0,他引:1
Dorota Walkowiak-Tomczak 《European Food Research and Technology》2002,215(5):401-406
The purpose of study was the determination of optimal conditions for red beet juice denitrification by Paracoccus denitrificans bacteria as well as the evaluation of the usefulness of microbiologically treated juice for the production of a natural colouring preparation for foods. Total reduction of nitrates was found during bacterial culturing at 25 and 30 °C, at an initial pH of 7.0-8.0 and juice osmotic pressure of 900-1100 mOsm/kg. Microbiological denitrification procedure affected colour, taste and aroma of the juice. However, the use of juice as food colouring and component was made feasible by acidification and partial evaporation of water together with volatile substances. 相似文献
113.
Liang Y.C. Wenjiang Zeng Pick Hong Ong Zhaoxia Gao Jun Cai Balasubramanian N. 《Electron Device Letters, IEEE》2002,23(12):700-703
In this letter, a concise process technology is proposed for the first time to enable the fabrication of good quality three-dimensional (3-D) suspended radio frequency (RF) micro-inductors on bulk silicon, without utilizing the lithography process on sidewall and trench-bottom patterning. Samples were fabricated to demonstrate the applicability of the proposed process technology. 相似文献
114.
115.
George Ter-Stepanian 《Bulletin of Engineering Geology and the Environment》2002,61(3):197-205
The paper discusses the postulated suspension force, by which it is possible to explain some enigmatic phenomena observed
in different types of mass movements. This force is generated in thick suspensions as a result of friction between sinking
solid particles and static water. The suspension force is related to the seepage force but they have opposite directions.
Both forces form flow networks. Having explained the suspension force, the paper describes how this influences the movement
of material, particularly in debris flows. Enigmatic features and the mechanism of debris flows and lahars are explained by
virtue of the suspension force.
Electronic Publication 相似文献
116.
Interfacial segregation of Ti in the brazing of diamond grits onto a steel substrate using a Cu-Sn-Ti brazing alloy 总被引:1,自引:0,他引:1
Wen-Chung Li Shun-Tian Lin Cheng Liang 《Metallurgical and Materials Transactions A》2002,33(7):2163-2172
Diamond grits were brazed onto a steel substrate using a prealloyed Cu-10Sn-15Ti (wt pct) brazing alloy at 925 °C and 1050
°C. Due to the relatively high concentration of Ti in the brazing alloy, the braze matrix exhibited a composite structure,
composed of β-(Cu,Sn), a Cu-based solid solution, and various intermetallic compounds with different morphologies. The reaction of Ti with
diamond yielded a continuous TiC layer on the surfaces of the diamond grits. On top of the TiC growth front, an intermetallic
compound, composed of Sn and Ti, nucleated and grew into a randomly interwoven fine lacey structure. An interfacial structure
developed as the interwoven fine lacey phase was semicoherently bonded to the TiC layer, with the Cu-based braze matrix filling
its interstices. The thickness of such a composite layer was increased linearly with the square root of isothermal holding
time at 925 °C, complying with the law of a diffusion-controlled process. However, at 1050 °C, the segregation behavior of
Ti and Sn to the interfaces between the TiC layer and the braze matrix diminished, due to the increased solubility of Ti in
the Cu-based liquid phase. The enhanced dissolution of Ti in the Cu-based liquid phase at 1050 °C also caused the precipitation
of rod-like CuTi with an average diameter of about 0.2 μm during cooling. SnTi3 was the predominant intermetallic compound and existed in three different forms in the braze matrix. It existed as interconnected
grains of large size which either floated to the surface of the braze matrix or grew into faceted grains. It also exhibited
a nail-like structure with a mean diameter of about 1 μm for the rod section and a lamellar structure arising from a eutectic reaction during cooling. 相似文献
117.
We consider the problem of rescheduling trains in the case where one track of a railway section consisting of two tracks
in opposing directions is closed due to construction activities. After presenting an appropriate model for this situation
we derive a polynomial algorithm for the subproblem of finding an optimal schedule with minimal latenesss if the subsequences
of trains for both directions outside the construction site are fixed. Based on this algorithm we propose a local search procedure
for the general problem of finding good schedules and report test results for some real world instances.
Received: December 8, 1999 / Accepted: May 2, 2001 相似文献
118.
Tsu-Hua Ai Jiann-Fuh Chen Tsorng-Juu Liang 《Industrial Electronics, IEEE Transactions on》2002,49(3):595-597
To overcome the problem of unequal switching loss in power switches, in conventional hybrid pulse width modulation (HPWM) full-bridge inverters, a random switching method for HPWM full-bridge inverters is proposed. The proposed method equalizes switching losses of the four switches, while also providing good output performance 相似文献
119.
Three interesterified vegetable oils (IVOs) prepared from palm, cottonseed, and olive oil, respectively, have been studied for application to Frankfurters. Beef fat (10%) was replaced by one of the IVOs at 20, 60 or 100%. Fatty acid composition of the lipid fraction in the Frankfurters and saturated/unsaturated ratios were established for all batches. We found that total or partial replacement of beef fat by IVOs did not lead to significant changes in appearance, colour, texture, flavour or sensory score. We conclude that IVOs may be successfully applied as beef fat substitutes in Frankfurters. 相似文献
120.
J-M Choe 《欧洲信息系统杂志》2002,11(2):142-158
This study empirically examined the organisational learning effects of the nonfinancial performance information provided by management accounting information systems (MAISs) under advanced manufacturing technology (AMT). In this study, a target costing system and the frequent and quick reporting of information were considered the facilitators of learning. First, we examined the relationships between AMT level and the amount of nonfinancial performance information produced by MAISs. The empirical results showed that there are significant positive relationships between the level of AMT and nonfinancial performance information. With a systems approach, we also proved the impact of the relationships among AMT levels, nonfinancial performance information and learning facilitators on the organisational performance of a firm. The results of our research suggest that under a high level of AMT, for the provision of information to result in an increase of performance through organisational learning, a target costing system must be introduced and a large amount of information should be provided frequently and quickly. The results of this study also showed that although AMT level may be low, fairly well-arranged facilitators and a moderately large amount of information may be necessary for the improvement of performance. In conclusion, effective organisational learning depends on the provision of relevant information as well as efficient learning support mechanisms. 相似文献