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Copyright of Journal of Northeastern University (Natural Science) is the property of Dongbei Daxue Xuebao 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.)

The non-contact measurement method is used to measure and evaluate the three-dimensional morphology of zirconia abrasive belts(P120, P320)and ceramic alumina belt(P120). The results show that the protrusion height of the zirconia abrasive belt and ceramic alumina belt is in the normal distribution and right-skewness distribution respectively. The protrusion area of the zirconia abrasive belt and ceramic alumina belt is both in the right polarized distribution. The protrusion height and area of abrasive grains decrease with the decrease of grain size. The protrusion height and area of abrasive grains in the ceramic alumina belt are smaller than those in the zirconia abrasive belt. The geometric shapes of the abrasive grains of the abrasive belts are similar to the spherical-top cone. The grain size has a significant effect on the spherical-top radius, i.e., the smaller the grain size, the smaller the spherical-top radius, but the effect on the cone apex angle is not significant. There are great differences in the spherical-top radius and cone apex angle of the two abrasive belts with the same particle size. [ABSTRACT FROM AUTHOR]

Copyright of Journal of Northeastern University (Natural Science) is the property of Dongbei Daxue Xuebao 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 Northeastern University (Natural Science) is the property of Dongbei Daxue Xuebao 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 Northeastern University (Natural Science) is the property of Dongbei Daxue Xuebao 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.)

Ｉｎ ｏｒｄｅｒ ｔｏ ｅｘｐｌｏｒｅ ｔｈｅ ｐｒｏｃｅｓｓｉｎｇ ｐｒｏｐｅｒｔｙ ｏｆ ｇｒｉｎｄｉｎｇ ｍｅｔａｍｏｒｐｈｉｃ ｌａｙｅｒｓ ｏｆ ｎｉｃｋｅｌ￣ ｂａｓｅｄ ｓｉｎｇｌｅ ｃｒｙｓｔａｌ ｓｕｐｅｒａｌｌｏｙꎬ ａ ｓｉｎｇｌｅ￣ｆａｃｔｏｒｉａｌ ｐｌａｉｎ ｇｒｉｎｄｉｎｇ ｅｘｐｅｒｉｍｅｎｔ ｗａｓ ｃｏｎｄｕｃｔｅｄ ｔｏ ｉｎｖｅｓｔｉｇａｔｅ ｔｈｅ ｅｆｆｅｃｔ ｏｆ ｄｉｆｆｅｒｅｎｔ ｇｒｉｎｄｉｎｇ ｐａｒａｍｅｔｅｒｓ ａｎｄ ｃｏｏｌｉｎｇ ｃｏｎｄｉｔｉｏｎｓ ｏｎ ｔｈｅ ｔｈｉｃｋｎｅｓｓ ｏｆ ｇｒｉｎｄｉｎｇ ｍｅｔａｍｏｒｐｈｉｃ ｌａｙｅｒｓ. Ｔｈｅ ｒｅｓｕｌｔｓ ｓｈｏｗｅｄ ｔｈａｔ ｔｈｅ ｇｒｉｎｄｉｎｇ ｍｅｔａｍｏｒｐｈｉｃ ｌａｙｅｒ ｗｉｔｈ ｃｅｒｔａｉｎ ｔｈｉｃｋｎｅｓｓ ａｐｐｅａｒｓ ｏｎ ｔｈｅ ｇｒｉｎｄｉｎｇ ｓｕｒｆａｃｅ ａｎｄ ｓｕｂｓｕｒｆａｃｅ ｏｆ ｎｉｃｋｅｌ￣ｂａｓｅｄ ｓｉｎｇｌｅ ｃｒｙｓｔａｌ ｓｕｐｅｒａｌｌｏｙ ＤＤ５. Ｔｈｅ γ ｐｈａｓｅ ａｎｄ γ′ ｐｈａｓｅ ｉｎ ｔｈｅ ｐｌａｓｔｉｃ ｄｅｆｏｒｍａｔｉｏｎ ｌａｙｅｒ ｏｆ ｔｈｅ ｍｅｔａｍｏｒｐｈｉｃ ｌａｙｅｒ ａｒｅ ｄｉｓｔｏｒｔｅｄ ｓｅｖｅｒｅｌｙꎬ ａｎｄ ｔｈｅ ｈａｒｄｎｅｓｓ ｏｆ ｔｈｅ ｇｒｉｎｄｉｎｇ ｍｅｔａｍｏｒｐｈｉｃ ｌａｙｅｒ ｉｓ ｇｒｅａｔｅｒ ｔｈａｎ ｔｈａｔ ｏｆ ｔｈｅ ｍａｔｒｉｘ. Ｔｈｅ ｇｒｉｎｄｉｎｇ ｍｅｔａｍｏｒｐｈｉｃ ｌａｙｅｒ ｔｈｉｃｋｎｅｓｓ ｖａｒｉｅｓ ｗｉｔｈ ｔｈｅ ｇｒｉｎｄｉｎｇ ｐａｒａｍｅｔｅｒｓ ａｎｄ ｃｏｏｌｉｎｇ ｃｏｎｄｉｔｉｏｎｓ. Ｗｉｔｈ ｔｈｅ ｉｎｃｒｅａｓｅ ｏｆ ｇｒｉｎｄｉｎｇ ｗｈｅｅｌ ｔａｎｇｅｎｔｉａｌ ｖｅｌｏｃｉｔｙꎬ ｔｈｅ ｍｅｔａｍｏｒｐｈｉｃ ｌａｙｅｒ ｔｈｉｃｋｎｅｓｓ ｆｉｒｓｔ ｄｅｃｒｅａｓｅｓꎬ ａｎｄ ｔｈｅｎ ｉｎｃｒｅａｓｅｓꎻ ｗｉｔｈ ｔｈｅ ｉｎｃｒｅａｓｅ ｏｆ ｇｒｉｎｄｉｎｇ ｄｅｐｔｈꎬ ｔｈｅ ｍｅｔａｍｏｒｐｈｉｃ ｌａｙｅｒ ｔｈｉｃｋｎｅｓｓ ｉｎｃｒｅａｓｅｓ ｃｏｎｔｉｎｕｏｕｓｌｙꎻ ｗｉｔｈ ｔｈｅ ｉｎｃｒｅａｓｅ ｏｆ ｗｏｒｋｐｉｅｃｅ ｆｅｅｄ ｖｅｌｏｃｉｔｙꎬ ｔｈｅ ｍｅｔａｍｏｒｐｈｉｃ ｌａｙｅｒ ｔｈｉｃｋｎｅｓｓ ｆｉｒｓｔ ｉｎｃｒｅａｓｅｓꎬ ａｎｄ ｔｈｅｎ ｄｅｃｒｅａｓｅｓ. Ｗｉｔｈｉｎ ｔｈｅ ｒａｎｇｅ ｏｆ ｅｘｐｅｒｉｍｅｎｔ ｐａｒａｍｅｔｅｒｓꎬ ｔｈｅ ｍｉｎｉｍｕｍ ｑｕａｎｔｉｔｙ ｌｕｂｒｉｃａｔｉｏｎ ( ＭＱＬ ) ｃｏｏｌｉｎｇ ｃｏｎｄｉｔｉｏｎ ｃａｎ ｒｅｄｕｃｅ ｔｈｅ ｃｏｒｒｅｓｐｏｎｄｉｎｇ ｇｒｉｎｄｉｎｇ ｍｅｔａｍｏｒｐｈｉｃ ｌａｙｅｒ ｔｈｉｃｋｎｅｓｓꎬ ｗｈｉｃｈ ｃａｎ ｂｅ ｒｅｄｕｃｅｄ ｂｙ ｕｐ ｔｏ ３. ５ μｍ. [ABSTRACT FROM AUTHOR]

The cone elimination method was used to generate the maximum boundary based on established numerical model of ore deposits considering slope angle and technical economic parameters.On the basis of the geological optimum candidate boundary sequence produced in the maximum boundary， five groups of staging ore volume were set up. By comparing the staging number， the amount of ore and rock in staging boundary， the net present value and the time span of each stage， the influence of staging ore volume on boundary optimization was analyzed. The optimization results showed that the lower limit of the staging ore volume remains unchanged and the upper limit increases， the staging number decreases from 9 to 8.The fluctuation of the mining amount and the rock stripping amount in the staging boundary mainly occurs in the first few stages. The total net present value has been increasing，however the increase is gradually decreasing. The lower limit of the staging time span is unchanged， the upper limit is gradually increasing. According to the total net present value and the staging time span， staging ore volume in 6~9a or 6~10a is more suitable to improve economic efficiency. [ABSTRACT FROM AUTHOR]

Copyright of Journal of Northeastern University (Natural Science) is the property of Dongbei Daxue Xuebao 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.)

Stock market network was constructed by using the minimum spanning tree method to study the evolution of MST structure， the topological indicators and individual behavior characteristics of the key nodes at different periods before， during and after the extreme volatility of stock indexes. The results showed that the China′s stock market industry has a strong concentration and industry-wide homogeneity. The MST network shrinks during extreme volatility， and the network expands after volatility. In the middle and late periods of extreme volatility， the sudden emergence of the materials industry and information technology industry occupies an important position in the network. The extreme volatility caused by different infectious sources has different ways of transmission risk. Extreme volatility in stock indexes exacerbates the linkage between stocks， assets are reconfigured in the market and the network structure is undergone new adjustments. [ABSTRACT FROM AUTHOR]

Copyright of Journal of Northeastern University (Natural Science) is the property of Dongbei Daxue Xuebao 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.)

Aiming at dissociation problem of Al-Fe in hydrometallurgical extraction process for high-iron diaspore bauxite， "calcification-carbonization-reducing iron" method was proposed for effectively extracting valuable metal Al and Fe. Andradite-grossular hydrogarnet was synthetized by pure material， and the transformation behavior in novel technology was investigated for effective dissociation and comprehensive recovery of Al-Fe from high-iron bauxite. The results showed that the andradite-grossular hydrogarnet is synthetized in the range of 483~533K in Na2O-Al2O3-CaO-SiO2-Fe2O3-H2O system， in which chemical property is relatively stable. In the carbonization process， andradite-grossular hydrogarnet is decomposed entirely， producing CaCO3， Ca2SiO4， Fe2O3 and a little grossular hydrogarnet. Moreover， 52.7% of Al2O3 is extracted in dissolving alumina process and 77.2% of Fe is reduced in the directly reducing iron process. [ABSTRACT FROM AUTHOR]

The gas emission law during excavation in coal mining is the fundamentals of prevention and control of gas disasters. For the gas emission law in the study， there is no accurate method to determine the problem of pre-exhaust gas zone width of seam roadway. Based on the theory of gas flow and coal and rock deformation， the gas flow equation of gas-containing coal and rock and the coal and rock roadway deformation equation were established， the flow solid coupling mathematical model of the seam roadway pre-exhaust gas zone was established as well. The Qinshui mining area excavated roadway was taken as an example of numerical simulation to obtain the characteristics of temporal and spatial evolution of gas-containing coal and rock roadway damage. Based on the tracing principle， the method of measuring the pre-exhaust gas zone width of the seam roadway was proposed， and the measured results were consistent with that of the numerical calculation. The research results help to solve the problem of prediction accuracy of gas emission in coal working face. [ABSTRACT FROM AUTHOR]

Copyright of Journal of Northeastern University (Natural Science) is the property of Dongbei Daxue Xuebao 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 Northeastern University (Natural Science) is the property of Dongbei Daxue Xuebao 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.)

Due to IMS (IP multimedia subsystem) does not support media relay-based multipath transmission mode at present， a session negotiation mechanism in IMS supporting media relay-based multipath transport was presented. Multipath transmission function was introduced to IMS system in a form of service. The multipath transport framework based on application-layer relay was combined with IMS system seamlessly. The network side of IMS was enabled to manage media multipath transmission process. The proposed mechanism not only maximize the reuse of existing IMS network infrastructure to protect the early capital investment and improve the scheme’s practicability， but also enable the network side of IMS to have the ability to provide users with differentiated media transmission quality. [ABSTRACT FROM AUTHOR]

Copyright of Journal of Northeastern University (Natural Science) is the property of Dongbei Daxue Xuebao 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.)