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Copyright of Journal of Forest & Environment is the property of Journal of Forest & Environment Editorial 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 Science Technology & Engineering is the property of Chinese Society of Technology Economics 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 Shenzhen University Science & Engineering is the property of Editorial Department of Journal of Shenzhen University Science & Engineering 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 Northern Agriculture / Beifang Nongye Xuebao is the property of Journal of Northern Agriculture Editorial 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 Forest & Environment is the property of Journal of Forest & Environment Editorial 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 Northern Agriculture / Beifang Nongye Xuebao is the property of Journal of Northern Agriculture Editorial 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 Southwest China Journal of Agricultural Sciences is the property of Editorial Department of Southwest China Journal of Agricultural Sciences 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 Electronic Components & Materials is the property of Electronic Components & Materials 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.)

This study was aimed at understanding the effects of nitrogen gradient loading on the growth and chlorophyll fluorescence characteristics of Phoebe bournei seedlings through a simulated experiment on two-year-old P. bournei seedlings under seven nitrogen levels, N0 (0 g·m-2·a-1), N1 (5 g·m-2·a-1), N2 (10 g·m-2·a-1), N3 (15 g·m-2·a-1), N4 (20 g·m-2·a-1), N5 (25 g·m-2·a-1), and N6 (30 g·m-2·a-1) after 6 months of planting. The results showed that with an increase in nitrogen concentration, seedling height, ground diameter, and whole plant biomass showed an increase-decrease-increase pattern. Seedling height reached the maximum at N1 (142.41 cm), ground diameter and whole plant biomass reached the maximum at N2 (15.31 mm and 192.22 g, respectively), and these growth indices increased by 48.33%, 28.55%, and 114.58%, respectively, compared with the control group. Different nitrogen gradient loading treatments promoted an increase in total chlorophyll content in the leaves of P. bournei seedlings; the total chlorophyll content in leaves of the N2 and N3 groups was significantly higher and that of the N6 group was significantly lower than in the leaves of the N0 group (P < 0.05). With an increase in nitrogen intensity, the maximum photochemical efficiency (Fv/Fm), potential photochemical activity (Fv/Fo), and actual photochemical efficiency (Yield) of P. bournei seedlings showed an increase-decrease-increase trend, and the photochemical quenching coefficient (qP) and nonphotochemical quenching coefficient (qN) showed a decrease-increase-decrease trend. From the perspective of chlorophyll fluorescence parameters, N3 and N4 were the optimum concentration ranges of N For P. bournei seedlings; the photosynthetic efficiency of P. bournei seedlings could be significantly improved by an appropriate increase in nitrogen supply. [ABSTRACT FROM AUTHOR]

Ａｉｍｉｎｇ ａｔ ｔｈｅ ｐｒｏｂｌｅｍ ｔｈａｔ ｔｈｅ ａｂｒａｓｉｖｅ ｇｒａｉｎ ｔｒａｊｅｃｔｏｒｙ ｗａｓ ｈｉｇｈｌｙ ｒｅｐｒｏｄｕｃｉｂｌｅ, ａｎｄ ｔｈｅ ｌａｐｐｉｎｇ ａｎｄ ｐｏｌｉｓｈｉｎｇ ｕｎｉｆｏｒｍｉｔｙ ｗａｓ ｉｎｓｕｆｆｉｃｉｅｎｔ ｉｎ ｔｈｅ ｃｏｎｖｅｎｔｉｏｎａｌ ｌａｐｐｉｎｇ ｐｒｏｃｅｓｓ, ｔｈｅ ｉｎｔｒｏｄｕｃｔｉｏｎ ｏｆ ｉｒｒａｔｉｏｎａｌ ｓｐｅｅｄ ｒａｔｉｏ ｏｆ ｔｈｉｓ ｎｅｗ ｃｏｎｃｅｐｔ, ｗａｓ ｅｘｐｅｃｔｅｄ ｔｏ ｆｕｒｔｈｅｒ ｅｎｈａｎｃｅ ｔｈｅ ｌａｐｐｉｎｇ ｐｒｏｃｅｓｓ ｕｎｉｆｏｒｍｉｔｙ. Ｔｈｅ ｍａｔｈｅｍａｔｉｃａｌ ｍｏｄｅｌ ｏｆ ｔｈｅ ｔｒａｊｅｃｔｏｒｙ ｏｆ ｔｈｅ ｅｃｃｅｎｔｒｉｃ ｍａｉｎ ｄｒｉｖｅ ａｎｄ ｔｈｅ ｌｉｎｅａｒ ｓｗｉｎｇ ｄｒｉｖｅ ｗａｓ ｅｓｔａｂｌｉｓｈｅｄ, ａｎｄ ｔｈｅ ｋｉｎｅｍａｔｉｃｓ ｓｉｍｕｌａｔｉｏｎ ｗａｓ ｃａｒｒｉｅｄ ｏｕｔ ｂｙ Ｍａｔｌａｂ. Ｔｈｅ ｔｒａｊｅｃｔｏｒｙ ｏｆ ｓｉｎｇｌｅ ａｎｄ ｍｕｌｔｉｐｌｅ ａｂｒａｓｉｖｅ ｇｒａｉｎｓ ｗｅｒｅ ｃｏｍｐａｒｅｄ ｂｅｔｗｅｅｎ ｔｗｏ ｄｒｉｖｉｎｇ ｍｏｄｅｓ ａｎｄ ｄｉｆｆｅｒｅｎｔ ｓｐｅｅｄ ｒａｔｉｏｓ. Ｆｉｎａｌｌｙ, ｔｈｅ ｕｎｉｆｏｒｍｉｔｙ ｏｆ ｌａｐｐｉｎｇ ｔｒａｊｅｃｔｏｒｙ ａｔ ｄｉｆｆｅｒｅｎｔ ｓｐｅｅｄ ｒａｔｉｏｓ ｗａｓ ａｎａｌｙｚｅｄ ｂｙ ｄｉｓｃｒｅｔｅ ｃｏｅｆｆｉｃｉｅｎｔ. Ｔｈｅ ｒｅｓｕｌｔｓ ｉｎｄｉｃａｔｅ ｔｈａｔ ｗｈｅｎ ｔｈｅ ｓｐｅｅｄ ｒａｔｉｏ ｉｓ ｒａｔｉｏｎａｌ, ｔｈｅ ｌａｐｐｉｎｇ ｔｒａｊｅｃｔｏｒｙ ａｒｅ ｒｅｐｅａｔｅｄ, ｓｐｅｅｄ ｒａｔｉｏ ｓｉｚｅ ａｎｄ ｄｒｉｖｅ ｍｏｄｅ ｈａｖｅ ａ ｇｒｅａｔ ｉｎｆｌｕｅｎｃｅ ｏｎ ｔｈｅ ｔｒａｊｅｃｔｏｒｙ ｕｎｉｆｏｒｍｉｔｙꎻ ｗｈｅｎ ｔｈｅ ｓｐｅｅｄ ｒａｔｉｏ ｉｓ ｉｒｒａｔｉｏｎａｌ, ｔｈｅ ｌａｐｐｉｎｇ ｔｒａｊｅｃｔｏｒｙ ａｒｅ ｏｐｅｎ, ｉｔｓ ｔｒａｊｅｃｔｏｒｙ ｕｎｉｆｏｒｍｉｔｙ ｉｓ ｂｅｔｔｅｒ ｔｈａｎ ｔｈｅ ｒａｔｉｏｎａｌ ｎｕｍｂｅｒ, ａｎｄ ｔｈｅ ｓｐｅｅｄ ｒａｔｉｏ ａｎｄ ｄｒｉｖｉｎｇ ｍｏｄｅ ｈａｖｅ ｌｉｔｔｌｅ ｅｆｆｅｃｔ ｏｎ ｔｈｅ ｔｒａｊｅｃｔｏｒｙ ｕｎｉｆｏｒｍｉｔｙ. Ｔｈｅ ｒｅｓｅａｒｃｈ ｐｒｏｖｉｄｅｓ ａ ｔｈｅｏｒｅｔｉｃａｌ ｂａｓｉｓ ｆｏｒ ｓｅｌｅｃｔｉｎｇ ｒｅａｓｏｎａｂｌｅ ｄｒｉｖｉｎｇ ｍｏｄｅ ａｎｄ ｓｐｅｅｄ ｒａｔｉｏ, ａｎｄ ｉｓ ｂｅｎｅｆｉｃｉａｌ ｔｏ ｉｍｐｒｏｖｅ ｔｈｅ ｑｕａｌｉｔｙ ｏｆ ｍａｃｈｉｎｅｄ ｓｕｒｆａｃｅ. [ABSTRACT FROM AUTHOR]

In order to study the temperature and pressure effects of the detonation wave generated by dust clouds in the surrounding environment and its damage law, the two-phase flow model and space-time conservation element and solution element method are used to simulate the propagation of 3.0 m radius detonation wave in the air, which is formed by uniformly distributing the suspended aluminum dust with the equivalence ratio of 1 and the particle radius of 2 μm. The pressure reaches to maximum of 2.10 MPa when the detonation wave arrives at 3.0 m from the boundary of cloud, and then the pressure will decrease. The reaction of aluminum dust particles is completed without surplus at 4.7 m from the boundary of cloud. The fireball formed by the dust reaction move outwards to reach at 10 m from the boundary of cloud. The central area of fireball is a high-temperature and low-density area with temperature of above 3 500 K and density of 0.120 kg/m2. The overpressure reaches to 0.10 MPa when the propagation distance of shock wave arrives at 24.5 m from the boundary of cloud. The overpressure reaches to 0.09 MPa when the shock wave arrives at 28.0 m from the boundary of cloud, which can cause serious injury to the human body. [ABSTRACT FROM AUTHOR]

Copyright of Guihaia is the property of Guihaia 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 Northeastern University (Social Science) / Dongbei Daxue Xuebao (Shehui Kexue Ban) is the property of Dongbei Daxue 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 Guihaia is the property of Guihaia 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 Mechanical & Electrical Engineering is the property of Mechanical & Electrical Engineering Magazine 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 distribution of particle sliding trajectories on wafer surface possessed great importance in the machined work-piece surface quality. Aiming at the problem that particle sliding trajectories with rational rotational speed ratio was periodic, the trajectory simulations were carried out based on the kinematic analysis. Numerical simulations of particle sliding trajectories were performed to examine the influence of the kinematic parameters on the polishing uniformity of typical rotary-type lapping equipment. A method of plane lapping with irrational rotational speed ratio was presented. The kinematic analysis and numerical calculation were used to discuss the effect of the rotating speed ratio on the trajectory uniformity by using Matlab and the lapping plate with preferred helix arrangement of fixed particle was selected.The results indicate that the trajectory distribution with irrational rotational speed ratio is more intensive and complicate than that with rational rotational speed ratio. For different irrational rotational speed ratio, the uniformity of trajectory distribution increases with increasing of rotational speed ratio gradually but it is more uniform with increasing of lapping time. The research provides theoretical guide to the design and development of new plan lapping equipment with condition of irrational rotating speed ratio. [ABSTRACT FROM AUTHOR]