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Copyright of World Regional Studies is the property of World Regional Studies 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 CT Theory & Applications is the property of Editorial Department of CT Theory & Applications 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.)

Channeling detection at the interface Ⅱ (cement-formation interface) is a key technical problem in the cementing quality evaluation. The structure and principle were introduced for the second generation of azimuthally acoustic bond tool (AABT2. 0). Different channeling situations at the interface II were simulated using the finite difference algorithm, and the application effects of AABT2. 0 were analyzed in determining the central azimuth and angle range of the channeling. The numerical simulation results show that the central azimuth of the channeling can be obtained by analyzing the amplitudes of casing waves received by different azimuth array elements in the arcuate phased array (APA) acoustic receiver station. Compared with the individual-reception mode, the measurement accuracy of the angle range is greatly improved when the APA acoustic receiver station works in the scanning-reception mode. The channeling distribution in different depth sections can be obtained intuitively by logarithmic normalized imaging. The work of this study lays a theoretical foundation for the processing of AABT2. 0 actual data. [ABSTRACT FROM AUTHOR]

In horizontal or high-inclination well sections, the casing and logging tool usually have downward eccentricity due to gravity, which interferes with the measurement response of azimuthally acoustic bond tool (AABT). The azimuth of the cement channeling cannot be effectively distinguished by AABT under these circumstances. In this paper, the measurement responses of AABT under the conditions of tool eccentricity and casing eccentricity are numerically simulated by a three-dimensional finite difference algorithm. The relationship between the eccentricity distance and the amplitude of received waveform in each azimuth is analyzed, and an azimuth measurement correction method of the cement channeling is proposed. The numerical simulation results show that the tool eccentricity has a great influence on the measurement response of AABT, and it is difficult to directly obtain the azimuth of the cement channeling from the amplitude distribution curve of the first arrival. Based on the response characteristics of the eccentric tool in the free casing condition, the eccentricity effect of the tool can be corrected. The azimuth of the cement channeling can be accurately obtained from the corrected amplitude distribution curve of the first arrival. The influence of casing eccentricity on the measurement response of AABT is quite small and can usually be ignored. The work of this study lays a theoretical foundation for the processing of AABT actual data. [ABSTRACT FROM AUTHOR]

Copyright of Journal of China University of Petroleum is the property of China University of Petroleum 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.)

【Objective】This paper aimed to isolate lead-resistant strains from heavy metal contaminated soil to provide a reference for soil heavy metal bioremediation. 【Method】The lead-resistant strains were isolated from heavy metal-contaminated soils, and one lead-resistant fungus（named PbW） was domesticated by Pb2+ concentration gradient culture. Its 18 S rRNA was sequenced, and phylogenetic tree was constructed. The maximum resistance level（MRL）, removal rate and adsorption efficiency of the strain were studied by Pb2+ concentration gradient. 【Result】The strain（PbW） was Phoma sp. The optimum environmental conditions were: temperature 25 ℃, pH 7, time 4-5 days, the maximum tolerated concentration of Pb2+ reached 6000 mg·L-1. The strain had the best removal and adsorption effect when the concentration of Pb2+ was 2000 mg·L-1, the adsorption rate reached 56.28 %, the removal rate reached 98.42 %, and the adsorption amount was 61.87 mg·L-1. 【Conclusion】This study showed that the strain（PbW） had a good adsorption and removal effects on Pb2+ in soil, which could have a good application prospect in microbial remediation of lead-contaminated soil. [ABSTRACT FROM AUTHOR]

Copyright of Journal of Agro-Environment Science is the property of Journal of Agro-Environment Science Editorial Board 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.)