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In the process of in situ leaching of ionic rare earthy the permeability of ore body is significant for the leaching rate of resources. The saturated permeability experiment of ionic rare earth under different leaching conditions was studied by variable head method, and the influence of leaching solution type and concentration on saturated permeability coefficient was analyzed. The relationship between the water content of ion type rare earth and matrix suction was studied by Geo Experts pressure plate instrument when the solution was pure water, 3% (NH4)2SO4, 3% MgSO4, respectively. Based on Van Genuchten model and Fredlund & Xing model, the effect of leaching solution type and concentration on unsaturated permeability of ionic rare earth orebody is discussed. The results show that the saturated/unsaturated permeability coefficients of ion type rare earth from large to small are pure water, 3% (NH4)2SO4MgSO4. The saturated permeability coefficient of ion rare earths increases first and then decreases. When the ore body is unsaturated, the matrix suction is an important factor affecting the unsaturated permeability co efficient due to the existence of matrix suction. Under the same matrix suction, the unsaturated permeability decreases with the increase of the concentration of leaching solution. The research not only provide theoretical guidance for the design of injection parameters of ln-situ leaching, but also is helpful to improve the efficient mining of ion-type rare earth. [ABSTRACT FROM AUTHOR]

Copyright of South China Fisheries Science is the property of South China Fisheries Science Editorial Department and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Chinese Medical Equipment Journal is the property of Chinese Medical Equipment Journal Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Chinese Medical Equipment Journal is the property of Chinese Medical Equipment Journal Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Chinese Medical Equipment Journal is the property of Chinese Medical Equipment Journal Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Chinese Medical Equipment Journal is the property of Chinese Medical Equipment Journal Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Chinese Medical Equipment Journal is the property of Chinese Medical Equipment Journal Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Journal of the Chinese Society of Rare Earths is the property of Editorial Department of Journal of the Chinese Society of Rare Earths and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Journal of the Chinese Society of Rare Earths is the property of Editorial Department of Journal of the Chinese Society of Rare Earths and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

BACKGROUND: In clinical practice, there are some patients with labial inclined anterior teeth which influence their appearance, but they refuse orthodontic treatment because of many factors such as long-term treatment. Alternatively, these patients can receive aesthetics restoration with re-directional post-core and crown. OBJECTIVE: To investigate the influence of three kinds of post-core materials on fracture resistant ability of labial inclined maxillary central incisor with different changed angles. METHODS: Seventy-five maxillary central incisors were randomly divided into three groups: group I was restored with Co-Cr post-core and porcelain-fused-to-metal (PFM) crown, group II was restored with 50% gold alloy post-core and PFM crown, group III was restored with everStick fiber post and composite resin core and PFM crowns. Each group then was divided into five subgroups based on angles between the post-core and long axis of the tooth (0°, 10°, 20°, 30°, 40°). All specimens were embedded in acrylic resin and fixed in electronic universal testing machine. Force was loaded to each specimen until fracture occurred, and the maximum load values of fracture and the fracture mode were recorded. RESULTS AND CONCLUSION: The fracture resistance of group III was superior to groups I and II (P < 0. 05), but there was no significant difference between group I and group II (P > 0.05). The maximum load value of the three groups decreased as the changed angle increased. The fracture of group III mostly appeared on the 1/3 of the root neck, while the fracture of groups I and II mostly appeared on the 1/3 of root central or the 1/3 of the root neck. So, the fracture resistance and fracture mode of central incisor under changed angles restored with everStick fiber post were superior to that with cast metal post-core. During re-directional restoration of labial inclined maxillary anterior teeth, everStick fiber post is recommended as a better choice to reduce the risk of catastrophic fractures. Also it suggests that excessive changed angle should be avoided to prevent root fracture. [ABSTRACT FROM AUTHOR]

In order to realize the remote monitoring of ion concentration, the article introduces a kind of remote monitoring system of ion concentration based on ZigBee wireless sensor network technology. The system adopts ZigBee wireless sensor network technology combined with GPRS and LabView 2011 to implement remote real-time monitoring and control of the ion concentration. Through the test, the system reaches the design requirements and provides the reliable guarantee for the plating product scientific, high efficient, safe, high-quality production. [ABSTRACT FROM AUTHOR]

Confining pressure has a great effect on the internal microstructure of the rock,and results in a change in wave impedance,which affects the propagation attenuation laws of the stress wave in the porous rock subjected to high stress.In order to investigate the effect of confining pressure on the characteristics of stress wave propagation in rock,the relationships between both reflection coefficient and transmission coefficient with the wave impedance of rock were established based on one dimensional stress wave theory. Then the short and long rock specimens were made of red sandstone,and the experiments of stress wave propagation in specimens under different confining pressures were carried out based on the modified Split Hopkinson Pressure Bar( SHPB).Also,the experimental longitudinal wave velocities,wave impedances,reflection coefficients and transmission coefficients of rock under different confining pressures were analyzed.Based on the empirical relationship between wave impedance and confining pressure,and the theoretical relationship between wave impedance and transmission coefficient,the theoretical transmission coefficients under different confining pressures were obtained and compared with experimental values.The comparison shows that the differences between theoretical and experiment values were very small,and verifies the theoretical analysis of transmission and reflection coefficients are valid.The influence laws of confining pressure on the stress wave propagation along red sandstone were obtained by the comprehensive analysis of longitudinal wave velocity,wave impedance,transmitted and reflected coefficients of rock under different confining pressures.The results show that both the longitudinal wave velocity and wave impedance of rock specimen increase with the increase in confining pressure.With the increase of confining pressure,the transmission coefficient of short specimen increases,and the absolute value of reflection coefficient decreases,the transmission coefficient of long specimen,however,decreases gradually.The variation trends of both the reflection coefficient and trans-mission coefficient with confining pressure can be fitted with quadratic function.All of the above variation tendencies show that the increase of confining pressure decreases the attenuation of its amplitude. [ABSTRACT FROM AUTHOR]