In this paper Lou＇s direct perturbation method is applied to the perturbed coupled nonlinear Schrodinger equations to obtain their asymptotical solutions, which include not only the zero-order solutions but also the ...In this paper Lou＇s direct perturbation method is applied to the perturbed coupled nonlinear Schrodinger equations to obtain their asymptotical solutions, which include not only the zero-order solutions but also the first-order modifications. Based on the asymptotical solutions, the effects of perturbations on soliton parameters and the collision between two solitons are then discussed in brief. Furthermore, we directly simulate the perturbed coupled nonlinear SchrSdinger equations by split-step Fourier method to check the validity of the direct perturbation method. It turns out that our analytical results are well supported by the numerical calculations.展开更多
In order to provide the scientific basis for the governance of Tien Lake. The experiment was conducted to investigate different types of surface soiI phospho-rus in Tien Lake Basin, the author malnIy studied the evoIu...In order to provide the scientific basis for the governance of Tien Lake. The experiment was conducted to investigate different types of surface soiI phospho-rus in Tien Lake Basin, the author malnIy studied the evoIution and the accumuIa-tion characteristics of the surface soiI phosphorus in Tien Lake Basin. The resuIts showed that： The content of surface soiI total phosphorus, OIsen-P and water soIu-bIe phosphorus in Tien Lake was significant accumuIated over the past 20 years. The content of total phosphorus, OIsen-P and water soIubIe phosphorus in different Iand utiIization types showed the same sequence： greenhouse soi〉arabIe soi〉buiIt-up area soi〉woodIand soiI. The content of soiI total phosphorus, OIsen-P and water soIubIe phosphorus was signal y reIevant. The content of soiI phosphorus in Tien Lake Basin had reached the IeveI of very rich, the accumuIation characteristic of phosphorus was obvious and there was a high risk of phosphorus poI ution.展开更多
Objective] This study almed to compare the effects of three absorbing medium on microwave degradation of chIordane in contaminated soiI under alkaline condition. [Method] SoiI sampIes were coI ected from the original ...Objective] This study almed to compare the effects of three absorbing medium on microwave degradation of chIordane in contaminated soiI under alkaline condition. [Method] SoiI sampIes were coI ected from the original site of a reIocated pesticide production enterprise as experimental materials, to investigate the effects of Cu2O, MnO2 and activated carbon powder as absorbing medium on soiI warming and removal rate of chIordane under alkaline condition with 20% moisture content. In addition, the effects of activated carbon as the optimal absorbing media on the removal rate of chIordane in contaminated soiI were analyzed, and the effects on the removal rate of chIordane in different weights of soiI sampIes were investigated. [Result] The effects of three different absorbing medium on the removal rates of chIordane demonstrated a descending order of activated carbon ＆gt; MnO2 ＆gt; CuO2. Under the same microwave condition, the removal rate of chIordane decreased with the increase of soiI weights, but the utiIization efficiency of microwave was improved continuousIy and tended to be stabiIized with the increase of soiI weights. [Conclu-sion] This study provided a theoretical basis for further Iarge-scale appIication in soiI remediation.展开更多
Objective] This study almed to investigate the characteristics of soiI total porosity （STP） and various factors affecting soiI water content （SWC） in eucalyptus pIantation （EP）, thereby providing references for ...Objective] This study almed to investigate the characteristics of soiI total porosity （STP） and various factors affecting soiI water content （SWC） in eucalyptus pIantation （EP）, thereby providing references for soiI water utiIization in eucalyptus pIanting in the red soiI hiI y region of South China. [Method] In the same cIimatic region, soiI sampIes were coI ected from surface soiI Iayer （A）, iI uvial horizon （B） and parent material horizon （C） in the upper sIope, middIe sIope and Iower sIope of eucalyptus pIantation, native forest and pine forest, respectiveIy, to determine the soiI porosity and soiI water content and analyze changes and various infIuencing factors of soiI water content in horizontal and vertical direction. [Result] Average soiI porosity in eucalyptus pIantation, native forest and pine forest was 45.9%, 41.4%and 55.3%, respectiveIy; soiI water content in these three forest stands was 13.3%, 13.4% and 15.5%, respectiveIy. In addition, soiI water content in these three forest stands exhibited no significant differences （P＆gt;0.05） among different soiI profiIes and sIope positions, but soiI water content in surface soiI Iayer varied significantIy （P＆lt;0.05） among different forest stands; in the horizontal direction, soiI water content exerted an extremeIy significant positive correIation with total coverage. [Conclusion] Total coverage of canopy Iayer, herb and Iitter Iayer is one of the most critical fac-tors affecting the changes of soiI water content in surface soiI Iayer of forest stands.展开更多
China is a Iarge agricuItural country and the coordinated deveIopment of rural economy, society and eco-environment pIays an important roIe in China ’s prosperity. Because of economy deveIopment, human factors and na...China is a Iarge agricuItural country and the coordinated deveIopment of rural economy, society and eco-environment pIays an important roIe in China ’s prosperity. Because of economy deveIopment, human factors and natural degrada-tion, however, the issue of rural environment poI ution is deteriorating as urban envi-ronment improves, becoming a key factor preventing rural sustalnabIe deveIopment. The research detalIed rural soiI contamination in China, analyzed major causes, and proposed suggestions on IegisIation on controIs of rural soiI poI ution.展开更多
We synthesize continuous solid solutions with monophasic zircon-type structure of vanadates of formula YxBi0.95 VO4：0.05Dy^3＋ （x = 0-0.95） using a combined method of co-precipitation and hydrothermal synthesis. Th...We synthesize continuous solid solutions with monophasic zircon-type structure of vanadates of formula YxBi0.95 VO4：0.05Dy^3＋ （x = 0-0.95） using a combined method of co-precipitation and hydrothermal synthesis. The X-ray diffractometer patterns confirm the formation of a solid solution of YBi0.95-xVO4：0.05Dy^3＋, and the results show that all the samples have monophasic zircon-type structure. The absorption spectra of the prepared phosphors show a blue-shift of the fundamental absorption band edge with increasing Y^3＋ content. An intense tunable characteristic emission of Dy^3＋ is observed with the increasing ratio of Y/Bi. Finally, the mechanism of luminescence of Dya＋ in the YBi0.95 VO4：0.05Dya＋ （x = 0-0.95） solid solution is analyzed and discussed.展开更多
SoiI in Africa is one of the most infertiIe soiIs on the earth. With soiIs in Burundi as study objects, the soiI-forming conditions, the properties of basic soiI types, and soiI improvement were discussed, which provi...SoiI in Africa is one of the most infertiIe soiIs on the earth. With soiIs in Burundi as study objects, the soiI-forming conditions, the properties of basic soiI types, and soiI improvement were discussed, which provides a reference for the decision maker and the rational deveIopment and utiIization of soiI in Burundi.展开更多
基金Project supported by the National Natural Science Foundation of China （Grant No 10575087） and the Natural Science Foundation of Zheiiang Province of China （Grant No 102053）. 0ne of the authors （Lin） would like to thank Prof. Sen-yue Lou for many useful discussions.
文摘In this paper Lou＇s direct perturbation method is applied to the perturbed coupled nonlinear Schrodinger equations to obtain their asymptotical solutions, which include not only the zero-order solutions but also the first-order modifications. Based on the asymptotical solutions, the effects of perturbations on soliton parameters and the collision between two solitons are then discussed in brief. Furthermore, we directly simulate the perturbed coupled nonlinear SchrSdinger equations by split-step Fourier method to check the validity of the direct perturbation method. It turns out that our analytical results are well supported by the numerical calculations.
基金Supported by the Science and Technology Major Projects of Tien lake of National Water Pollution Control and Management"Integrated Control and Water Conservation Forest protection Key Technology and Engineering Demonstration of Agricultural Non-point Source Pollution in Tien Lake Basin"(2012ZX07102-003)Applied Basic Research Major Projects of Yunnan Province"The Research on Phosphorus Supergene Migration and Aquatic Organisms Response of Tien Lake"(2009CC006)~~
文摘In order to provide the scientific basis for the governance of Tien Lake. The experiment was conducted to investigate different types of surface soiI phospho-rus in Tien Lake Basin, the author malnIy studied the evoIution and the accumuIa-tion characteristics of the surface soiI phosphorus in Tien Lake Basin. The resuIts showed that： The content of surface soiI total phosphorus, OIsen-P and water soIu-bIe phosphorus in Tien Lake was significant accumuIated over the past 20 years. The content of total phosphorus, OIsen-P and water soIubIe phosphorus in different Iand utiIization types showed the same sequence： greenhouse soi〉arabIe soi〉buiIt-up area soi〉woodIand soiI. The content of soiI total phosphorus, OIsen-P and water soIubIe phosphorus was signal y reIevant. The content of soiI phosphorus in Tien Lake Basin had reached the IeveI of very rich, the accumuIation characteristic of phosphorus was obvious and there was a high risk of phosphorus poI ution.
基金Supported by Special Fund for the Transformation of Scientific and Technologica Achievements in Jiangsu Province(BA2013057)~~
文摘Objective] This study almed to compare the effects of three absorbing medium on microwave degradation of chIordane in contaminated soiI under alkaline condition. [Method] SoiI sampIes were coI ected from the original site of a reIocated pesticide production enterprise as experimental materials, to investigate the effects of Cu2O, MnO2 and activated carbon powder as absorbing medium on soiI warming and removal rate of chIordane under alkaline condition with 20% moisture content. In addition, the effects of activated carbon as the optimal absorbing media on the removal rate of chIordane in contaminated soiI were analyzed, and the effects on the removal rate of chIordane in different weights of soiI sampIes were investigated. [Result] The effects of three different absorbing medium on the removal rates of chIordane demonstrated a descending order of activated carbon ＆gt; MnO2 ＆gt; CuO2. Under the same microwave condition, the removal rate of chIordane decreased with the increase of soiI weights, but the utiIization efficiency of microwave was improved continuousIy and tended to be stabiIized with the increase of soiI weights. [Conclu-sion] This study provided a theoretical basis for further Iarge-scale appIication in soiI remediation.
基金Supported by National Natural Science Foundation of China(U1033004)Open Fund of Key Laboratory of Plant Nutrition and Fertilizer,Ministry of Agriculture(2012-03)+3 种基金Major Science and Technology Project of Guangxi Zhuang Autonomous Region(GKZ1347001)Natural Science Foundation of Guangxi Zhuang Autonomous Region(2012GXNSFAA053066)Special Fund for the Basic Research and Operating Expenses of Guangxi Academy of Agricultural Sciences(GNK2013YM11,GNK2015YM11)Open Project of Guangxi Key Laboratory of Superior Timber Trees Resource Cultivation(13B0201)~~
文摘Objective] This study almed to investigate the characteristics of soiI total porosity （STP） and various factors affecting soiI water content （SWC） in eucalyptus pIantation （EP）, thereby providing references for soiI water utiIization in eucalyptus pIanting in the red soiI hiI y region of South China. [Method] In the same cIimatic region, soiI sampIes were coI ected from surface soiI Iayer （A）, iI uvial horizon （B） and parent material horizon （C） in the upper sIope, middIe sIope and Iower sIope of eucalyptus pIantation, native forest and pine forest, respectiveIy, to determine the soiI porosity and soiI water content and analyze changes and various infIuencing factors of soiI water content in horizontal and vertical direction. [Result] Average soiI porosity in eucalyptus pIantation, native forest and pine forest was 45.9%, 41.4%and 55.3%, respectiveIy; soiI water content in these three forest stands was 13.3%, 13.4% and 15.5%, respectiveIy. In addition, soiI water content in these three forest stands exhibited no significant differences （P＆gt;0.05） among different soiI profiIes and sIope positions, but soiI water content in surface soiI Iayer varied significantIy （P＆lt;0.05） among different forest stands; in the horizontal direction, soiI water content exerted an extremeIy significant positive correIation with total coverage. [Conclusion] Total coverage of canopy Iayer, herb and Iitter Iayer is one of the most critical fac-tors affecting the changes of soiI water content in surface soiI Iayer of forest stands.
文摘China is a Iarge agricuItural country and the coordinated deveIopment of rural economy, society and eco-environment pIays an important roIe in China ’s prosperity. Because of economy deveIopment, human factors and natural degrada-tion, however, the issue of rural environment poI ution is deteriorating as urban envi-ronment improves, becoming a key factor preventing rural sustalnabIe deveIopment. The research detalIed rural soiI contamination in China, analyzed major causes, and proposed suggestions on IegisIation on controIs of rural soiI poI ution.
基金supported by the National 973 P rogram of China(No.2011CB211708)the National Natural Science Foundation of China(Nos.51272097,61265004,and 61307111)
文摘We synthesize continuous solid solutions with monophasic zircon-type structure of vanadates of formula YxBi0.95 VO4：0.05Dy^3＋ （x = 0-0.95） using a combined method of co-precipitation and hydrothermal synthesis. The X-ray diffractometer patterns confirm the formation of a solid solution of YBi0.95-xVO4：0.05Dy^3＋, and the results show that all the samples have monophasic zircon-type structure. The absorption spectra of the prepared phosphors show a blue-shift of the fundamental absorption band edge with increasing Y^3＋ content. An intense tunable characteristic emission of Dy^3＋ is observed with the increasing ratio of Y/Bi. Finally, the mechanism of luminescence of Dya＋ in the YBi0.95 VO4：0.05Dya＋ （x = 0-0.95） solid solution is analyzed and discussed.
基金Supported by Guangxi S&T Development Planning Program(14125007-2-7)~~
文摘SoiI in Africa is one of the most infertiIe soiIs on the earth. With soiIs in Burundi as study objects, the soiI-forming conditions, the properties of basic soiI types, and soiI improvement were discussed, which provides a reference for the decision maker and the rational deveIopment and utiIization of soiI in Burundi.
