最新刊期
卷 54 ， 期 6 ， 2015
- 摘要：Naringin is a pharmacologically active compound extracted and purified from Citri Grandis Exocarpium (Huajuhong). During the past more than ten years, naringin has been developed into a classⅠinnovative drug to treat cough by our group. The Drug Clinical Trial Approval of naringin was issued by China Food and Drug Administration. As such, this review aims to summarize all of pre-clinical studies of naringin from our laboratory, including pharmacological effects and acting mechanisms, non-clinical pharmacokinetics and toxicological evaluation.关键词：class Ⅰ new drug;naringin;pre-clinical research;pharmacological effect;pharmacokinetics;toxicology
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发布时间：2023-12-11 - 摘要：In order to investigate the protective effects of 〖WTBX〗Momordica charantia〖WTBZ〗 extract (MCE) on obesity and insulin resistance, C57BL/6j mice fed in a high-fat diet (HFD) were used as animal model. Obese mouse model was successfully made after 2-week HFD induction. The mice were then randomly divided into normal control, model control, MCE dose of 13.5, 27.0, and 54.0 g/kg treated groups. Mice in normal and model control groups were treated with 0.5% CMC-Na, and other groups were treated with MCE (i.g.), respectively, with the same volume twice a day for ten weeks. It was shown that the body weight, epididymal and total visceral white adipose tissue weight were decreased by treatment of MCE 54.0 g/kg without the change of food intake. The increased serum TG, CHO, LDL-C, glucose, insulin concentration and insulin resistance index were significantly inhibited. The concentration of TG was also decreased by the treatment of MCE 27.0 g/kg; while the concentration of HDL-C was increased by the treatment of MCE 13.5, 27.0 and 54.0 g/kg, respectively The adipocyte hypertrophy induced by HFD was mitigated by MCE dosedependently.
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发布时间：2023-12-11 - 摘要：To investigate the relationship between the expression levels of exogenous gene and methylation level of promoter in cells derived from transgenic pigs, the EGFP fluorescence of the fifth, 10thand 15thgeneration fibroblast of EGFP transgenic pigs were detected by flow cytometry, and the methylation status of a 560-bp region of the CMV promoter containing one CpG island including 30 CpG sites were examined by bisulfite sequencing method. The mean fluorescence intensity declined from the fifth generation of transgenic pig cells to the 10th generation cells, however, it increased to the level comparable to the fifth generation of cells from the 10thto 15thcells. The methylation level of the fifth, 10thand 15thgeneration cells of the CMV promoter were 3.64%±1.25, 2.97%±1.03 and 1.65%±0.74, respectively. The difference of methylation level among different generation of transgenic cells was insignificant, which indicated that the expression level of exogenous gene EGFP was not closely correlated to the methylation level on CMV promoter.关键词：methylation;promoter;CpG island;transgenic pig
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发布时间：2023-12-11 - 摘要：To learn more about the effects of transcription on DNA structure in E. coli topA-mutant, the plasmid pJGX15A, carrying a tandem transcription unit of tetA-cfaABCE, was used as the reporter plasmid. The topology of pJGX15A from HB101 (topA+gyrB+) and DM800 (topA-gyrB225) cells was then analyzed by chloroquine agarose gel electrophoresis. And, a type of irregular condensed structures of pJGX15A was found in DM800 cells. The condensed plasmid DNA had a high mobility rate and appeared to be smear bands in agarose gel electrophoresis. The topology of pJGX15A was also greatly affected by both cell growth phase and concentration of tetracycline in medium. The condensed structures were only formed in DM800 cells of exponential phase cultured in the medium with the concentration of tetracycline below 6 μg/mL. AFM images showed that these plasmid DNA molecules contained intramolecular conde nsation to different levels instead of normal supercoils. Some of the molecules were even completely condensed to a coil.关键词：DNA condensation;transcription;atomic force microscopy;Escherichia coli;topA-mutant
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发布时间：2023-12-11 - 摘要：The soluble proteins in Nilaparvata lugens adults and nymphs were analyzed by SDSPAGE electrophoresis. Results showed that there were almost equal number protein bands in all types of adult samples, most bands in different wing or gender samples existed content differences except female adult-specific protein band. There were four bands significantly higher in long-winged adult samples than in short-winged adult samples; in the comparison of male and female adult samples, it was found that there were two bands higher in males than in females, while other three bands higher in females than in males. The bands in nymph samples were gradually increased with the increase of age, four bands were constantly expressed in each instar period, one more band appeared in 5thinstar nymph samples, and one band could be detected from the 4thinstar. In addition, the contents of two bands were found much higher in long wing bud nymphs (9.029, 9.563 ng/μL) than those in short wing bud nymphs (5.133, 3.111 ng/μL) Last we discussed the relationships among the different bands and wing dimorphism or sex differentiation in insects.关键词：SDS-PAGE;Nilaparvata lugens St.l;soluble proteins;wing dimorphism
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发布时间：2023-12-11 - 摘要：In order to examine the effect of emamectin benzoate to Frankliniella occidentalis, the toxicity of this insecticide to the adult and 2nd instar of F. occidentalis were studied by dip method in this paper. In addition, the content of soluble protein, soluble sugar and lipid in F. occidentalis were also tested after these insects were exposed to medial lethal doses of emamectin benzoate for the following exposure times: 2, 4, 6, and 8 h. Furthermore the utilization rate of the energy source in F. occidentalis was calculated after the insects were exposed to emamectin benzoate until dead at the medial lethal doses. The results showed that emamectin benzoate had different toxicity to the adult and 2nd instar of F. occidentalis, and the medial lethal doses were 1.11 and 0.62 mg/L, respectively. With the extension of exposure time at medial lethal doses of emamectin benzoate, there was significant a increase or decrease on the content of soluble protein, soluble sugar and lipid in F. occidentalis adult, but no significant variation on their content in F. occidentalis nymph. When the F. occidentalis was dead under the medial lethal doses exposure, there was significant difference in the utilization rate of the three kinds of energy sources in F. occidentalis, the utilization was soluble sugar（74.12%）> soluble protein（58.10%）> lipid（42.13%）in adult, significantly higher than that in nymph at any kind of the three energy sources, and the utilization was soluble sugar（64.01%）> soluble protein（48.12%）> lipid（36.48%）in nymph. According to the results, we could conclude that the different variation and utilization of energy source between F. occidentalis adult and nymph under the exposure of emamectin benzoate, may have some relationship to their different tolerance to this insecticide.关键词：emamectin benzoate;medial lethal doses;Frankliniella occidentalis;energy source
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发布时间：2023-12-11 - 摘要：The primary principle of Monte Carlo method in solving the initial-boundary value problem for partial differential equations is introduced. And an improved strategy to solve the slow speed problem in computations with large grid points and random walks is proposed. Through the theoretical analysis and numerical validation, the improved strategy not only takes much less computational time, but also gives more accurate results comparing to the traditional methods under the same conditions.关键词：initial-boundary value problem;Monte Carlo method;random walk
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发布时间：2023-12-11 - 摘要：A class of nonlinear surface waves along the boundary of crystal is studied. Firstly, the surface wave equation along the boundary of crystal is built. Leading into a functional with the new restricted variation and its variational is calculated. Secondly, a new improved generalized variational iteration is structured. Then the initial function of solution for corresponding problem is structured. From the new variational iteration, the each time asymptotic analytic solution is found successively. And from example, the accuracy of solution is very good by using this method. Finally, the physical meaning of obtained asymptotic solution is related.关键词：surface waves;asymptotic solution;variational;crystal
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发布时间：2023-12-11 - 摘要：The theory of compressed sensing points out that, sparse (or compressible) signals can be reconstructed with high probability by lower sampling frequency. In more and more practical applications, many signals are sparse or approximately sparse in terms of some frames rather than orthonormal bases. In such settings, one approach to recover the signals is known as l1-analysis . Some recent study using alternative dual frames as analysis operators, and provide a weaker condition than existing results in the literature. Inspired by this, the recovery of such kind of signals with general dual frame via lp-Minimization (0关键词：compressed sensing;signal recovery;frame;dual frame;l1-analysis
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发布时间：2023-12-11 - 摘要：A class of even order neutral functional partial differential systems with continuous delay and nonlinear diffusion term is studied. By using a new technique based on a class of kernel functions Φ(t,s,r) and Riccati's transformation, some new sufficient conditions for oscillation of all solutions of such systems are established under Robins boundary value condition.关键词：oscillation;functional partial differential system;even order;neutral type;kernel function
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发布时间：2023-12-11 - 摘要：The problem of high energy consumption producing from big data processing is an important issue that needs to be solved, especially under the background of data explosion. Based on analyzing problems of the existing data layout policy, the problems of the in adaptation of energy-saving mode based on storage area division and heterogeneous HDFS cluster, the inflexibility of data block segmentation algorithm, the randomness of storage node selection, proposing a data layout strategy orienting to energy conservation are analyzed. Firstly, the new strategy divides the cluster into two different storage areas to meet the needs of saving energy: Active-Zone and Sleep-Zone; secondly, the new strategy has made improvements on traditional data block computing method, proposes a minimum number of jobs calculation method to determine the number of data blocks; at last, the new strategy can increase the adaptability of the heterogeneous cluster environment and can choose the appropriate storage nodes according to different job types. Experimental results show that the new data layout strategy can adapt to the heterogeneous cluster environment and reach the goal of reducing energy consumption for MapReduce jobs.关键词：green computing;MapReduce;heterogeneous environment;data layout
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发布时间：2023-12-11 - 摘要：Magnetic anisotropy and ultrafast demagnetization dynamics of full-Heusler Co2FeAl0.5Si0.5(CFAS) films doped with different concentration of rare-earth Tb are studied by using femtosecond time-resolved magneto-optical Kerr spectroscopy. It is found that the magnetization precession arises in low Tb-content doped CFAS films, but does not arise in the higher Tb-content doped CFAS films, and only a spike occurs near zero delay time for the CFAS film with the highest Tb content. Those phenomena imply that different content of Tb has influenced the magnetic anisotropy of CFAS films. Meanwhile, ultrafast demagnetization dynamics without precession oscillation presents a two-step demagnetization process. The first-step fast demagnetization is assigned to the ultrafast demagnetization of 3d moments of transition metal (FeCo), while the second-step slower one is ascribed to the demagnetization of 4f moments of Tb by 3d5d6s-4f coupling. The results show that the magnetic anisotropy of CFAS films can be controlled by adjusting the doping content of Tb. Tb-doping induced perpendicular magnetization CFAS magnetic films have a great potential applications in the fabrication of spintronic devices.关键词：time-resolved magneto-optical Kerr spectroscopy;Heusler alloys;RE-element Tb;magnetic anisotropy
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发布时间：2023-12-11 - 摘要：The design of cache size is one of the core issues in the research of caching strategies in Information-centric Networking, and the effective implementation of cache strategies is directly controlled by the pros and cons of the cache size allocation scheme. A novel cache size allocation scheme is proposed based on the node importance to community (NIC), and compared with the previous DC scheme that based on the node degree centrality. The simulation results show that NIC strategy can improve the utilization of network cache space and the network transmission performance.关键词：information-centric networking;cache;cache size;Node's important to community
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发布时间：2023-12-11 - 摘要：This work provides an optical manipulation method for oscillating trapping of a single nanoparticle with a tapered optical fiber. The tapered optical fiber was drawn by a flame heating technique using a singlemode optical fiber with the diameter of the tapered end being 1 μm. With a laser beam at a wavelength of 808 nm and an optical power of 30 mW launched into the tapered fiber, a single SiO2nanoparticle with a diameter of 800 nm is trapped by the optical gradient force along the tapered fiber direction. The trapping is a periodic oscillated near the focus point of the tapered fiber tip. The period of particle oscillation is about 0.8 s, and the distance of the oscillation center is about 4.4 μm to tapered fiber tip, while the particle oscillation amplitude is about 1.45 μm The method may provide an opportunity for the oscillating dynamic study of micro/nano particles and biological cells.关键词：optical trapping;tapered optical fiber;nanoparticles;oscillating manipulation
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发布时间：2023-12-11 - 摘要：An efficient local contrast and block compressed sensing(BCS) based on multi-focus image fusion algorithm is proposed. Firstly, structural random matrix is used as measurement matrix to obtain a high efficiency sample performance. Secondly, a local contrast measurement in CS domain is proposed to classify the clarity block and the de-focus block, and upon which the larger local contrast block is selected as the fused block. Thirdly, a consistency verification process based on majority filter is introduced to modify the initial fusion CS image. Finally, smoothed projection Landweber (SPL) algorithm is used to reconstruct the fused image to overcome the block artifact. The experimental results show that，compare to the current BCS based image fusion methods, the proposed method achieves good improvement in subjective visual perception quality as well as in objective quantified quality index such as information entropy, mutual information and average gradient for multifocus image fusion.关键词：image fusion;block compressed sensing;local contrast;consistency verification
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发布时间：2023-12-11 - 摘要：Use two special soil of southwest mountainous areas of red clay soil and powdered coal as research object, by conventional direct shear test, to study the influence of moisture content on these two soil of cohesion and internal friction angle, shear strength and other characteristics parameters. The results indicate that the red clay and powered soil of coal measure strata have water sensitivity, and the red clay water have larger sensitivity. With increase of water content, the cohesion of red clay decreases in segments. When water content approaches saturation moisture content, the cohesion of red clay is stable. The internal friction angle of red clay keeps stable at the beginning and then sharply declines with water content increasing. With increase of water content, the cohesion of powered soil of coal measure strata and its water content decreases in the form of exponential function, while its internal friction angle decreases in the form of linear function. The research results provide a reference for the region of soil mechanics calculation parameter selection.关键词：red clay;powered soil of coal measure strata;water sensitivity;direct shear test
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发布时间：2023-12-11 - 摘要：Soils moving is one of the geotechnical problems, which can be described as a granular flow induced by inclined plane. This work aims to investigate the drag and lift forces acting on the inclined intruder. By using the inertial number concept to confirm the flow regime, a parameter named dynamic friction coefficient is induced to this non-quasi-static flow. By improving the Coulomb model, the displacement field is obtained by two dimensional discrete element method, and the wedge model for drag and lift forces is built. The results show that drag force is dependent of the inclined angle when the other conditions are the same, but the lift force is decreasing with the inclined angle. Drag and lift forces are the horizontal and vertical components of the total force, respectively. And the ratio of drag and lift forces is just equal to the tangent value of the inclined angle. The dynamic friction angle is the quadratic function of velocity and inclined angle. This model can predict different case in different inclined angle and velocity.关键词：drag and lift forces;modified Coulomb model;granular media;inclined plane
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发布时间：2023-12-11 - 摘要：Clustering analysis is a statistical analysis method, which aims to classify the data from their similarities. Based on road network topology，a new algorithm had been put forward to achieve the clustering analysis for points of interest(POI) in transportation field. The algorithm is that POI taken from point sets would be extend to the adjacent node and has a breadth of search along the direction of the network topology with limiting conditions of aggregating degree(α) and extending degree(β). POI those meet the conditions would be clustered together. At last, this algorithm is applied in the Guangzhou Pearl River Metro network to analysis pedestrian accessibility.关键词：clustering analysis;network topology;POI;algorithm;pedestrian accessibility
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发布时间：2023-12-11 - 摘要：To improve the property of poloxamer hydrogels, temperature sensitive hydrogels were prepared from poloxamer and five kinds of polysaccharides as well as their derivatives with different chemical structures in this work. The effect of the chemical structures of polysaccharides and their derivatives on the hydrogel properties was investigated. The result indicated that the polysaccharides and their derivatives could form the hydrogels with poloxamer at the temperature (34~37 ℃) near human beings-temperature, which is advantageous for the injection application. The amphiphilic polysaccharide derivative/poloxamer hydrogels exhibited higher stabilities, stronger shear thinning behaviours, longer time for releasing hydrophobic drug of prednisone. These properties are probably related to the hydrophobic interactions between the amphiphilic polysaccharide derivatives and poloxamer. Five kinds of temperature sensitive hydrogels all exhibited the property for promoting the growth of osteoplasts, showing the potential application in the osseous junction's tissues.关键词：polysaccharide;polysaccharide derivative;poloxamer;temperature-sensitive hydrogel;prednisone
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发布时间：2023-12-11 - 摘要：Two new oleanane-type triterpenoids,(3E,23E)-3-caffeoyl-23-coumaroylhederagenin (1) and (3E,23E)-dicoumaroylhederagenin (2), together with two known analogues were isolated from the stems of traditional Chinese medicine Alangium chinense. The structures of two new compounds were determined by the spectroscopic method, and the known compounds were defined as (23E)coumaroylhederagenin (3) and (23Z)coumaroylhederagenin (4) based on the observed and reported NMR data. All compounds were isolated from the genus Alangium for the first time.关键词：Alangium chinense;Alangiaceae;oleananetype triterpenoids
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发布时间：2023-12-11 - 摘要：PI solid phase microextraction coating was prepared from pyromellitic acid dianhydride and 4,4′-diamino-diphenylether. PI coating was modified by ethyl silicate and 1,3-bis(3-aminopropy)tetra-methyldisiloxane.Ethyl silicate modified PI coating and silane coupling agent modified PI coating were synthesized.The structure of the coating was characterized by IR.The thermostability of the coating was examined by thermal analysis.The element composition and chemical environment of the coating surface was analyzed by X-ray photoelectron spectroscopy.The effect of surface structure and adsorption performance of the coating was investigated. The benzene adsorption quantity of the silane coupling agent modified PI coating was greater than the ethyl silicate modified PI coating and PI coating.关键词：solid phase microextraction;polyimide siloxane;XPS;surface structure
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发布时间：2023-12-11 - 摘要：The solid wastes in the e-waste dismantling industry in Qingyuan city were sampled, investigated, and divided into three categories, including entrained solid waste, solid waste generated by disassembly, solid waste generated from regeneration. The resource potential and potential risk of contamination of different solid wastes were then evaluated by testing calorific value, metal components, leaching toxicity. After investigating the resource and harmless disposal technology of solid waste in the e-waste dismantling industry, shaker sludge, waste wire and cable slag which have a large quantity and weak research foundation, we emphatically researched on the resource technology. Based on these researches, the classification management system of solid waste in the e-waste dismantling industry in Qing yuan city was built, that was “fine classification, resource recovery, harmless disposal, system monitoring”. This management system could provide policy recommendations to relevant management departments and lay the theoretical and practical basis for the future construction of regional dismantling solid waste sorting center关键词：E-waste;dismantling industry;solid waste;classification management system
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发布时间：2023-12-11 - 摘要：The basic magnesium chloride whiskers with good whisker quality and smooth surface were synthesized by liquid precipitation reaction method using Xuwen salt field brine as raw materials and sodium hydroxide as the precipitant. The phase, purity, structure of crystal morphology, crystal growth orientationof whiskers samples were characterized by elementary analysis, X-ray diffraction (XRD), scanning electron microscopy (SEM) and high resolution transmission electron microscopy (HRTEM). The SEM analysis revealed that the basic magnesium chloride whiskers showed fine dispersive capability, and the distribution of particle sizes was uniformity. The basic magnesium chloride whiskers with a welldefined shape as well as well straight whisker could be obtained under the following conditions: reaction temperature of 35 ℃, and reaction time of 50 h. The preparation method is simple, and the production cost is low in this work. It is thus expected to use Xuwen salt field brine to a large-scale experiment.关键词：basic magnesium chloride;whisker;brine;reinforcement and toughening agents;flame-retardant
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发布时间：2023-12-11 - 摘要：The discrimination of grain size of modern aeolian sands and beach sands is one of the heated argument problems in coastal aeolian research. Based on the data of grain size of 141 modern Aeolian sand samples and 70 beach sand samples from the southern Fujian coast, eastern Guangdong coast, western Guangdong coast and Hainan island coast which are the typical coastal dune distribution places in south China coast, the modern aeolian sands and beach sands are quantitatively discriminated by use of the multivariate linear discriminant analysis method and B-P artificial neural network analysis method. The results show that the B-P artificial neural network analysis method has higher discrimination precision than the multivariate linear discriminant analysis method. Modern aeolian sands and beach sands in Hainan island coast could be discriminated based on the grain size data by use of the B-P artificial neural network analysis method. However, viewing the results as a whole, the modern aeolian sands and beach sands in south China coast could not be significantly discriminated based on grain size by using two quantitative discriminated methods.关键词：south China coast;Aeolian sands;beach sands;grain size;quantitative discrimination
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发布时间：2023-12-11 - 摘要：The Bangong Co-Nujiang metallogenic belt is one of the most important metallogenic belts in Tibet. Its geochemical characteristics of LongbakangdongKangjia section at Buzicun village are analyzed based on the result of 1∶50 000 stream sediment survey, including distribution and anomaly characteristics of ore-forming elements on the surface, and the characteristics of anomaly element combination. The results show that metal anomaly occur in combination of multiple metal elements, and the highest anomaly is Au-Cu combination, the second is front elements combination of As-Sb-Ag-Cd-Pb, then rear element combination of Bi-W-Mo. The anomaly areas of front elements, ore-forming elements, and rear elements are distributed from west to east, and the halos have good zonation, suggesting that there may be a porphyritic type Cu-Au deposit in study area, and Longbakangdong-Kangjia anomaly area may be a potential area for prospecting large copper-gold deposit.关键词：Tibet;Bangong Co-Nujiang metallogenic belt;geochemical anomaly;potential ore
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发布时间：2023-12-11 - 摘要：Considering the influents of both runoff and winds, Circulations in the Hedi reservoir from January 2013 to March 2014 were simulated using FVCOM. Simulated results agree well with the observations during March 2014. Comparisons among the circulations caused by runoff, different dominant winds and both runoff and winds during 2013 showed that: ① The structure of the circulations changed with the dominant winds. Under the NNE wind, several anticlockwise circulations were observed, and the west coast flow was stronger than the east coast, while under the S or SSE wind, clockwise and anticlockwise circulations were found at the same time, and the east coastal currents were stronger than the west. ② During the winter half year, when runoff was weak while winds were stronger, the winds controlled the horizontal and vertical circulations; During the summer half year, when runoff was stronger with reverse winds, the runoff controlled the circulations. ③ The main circulations were anticlockwise for the whole reservoir in the annually average level, and the coastal currents were strong, especially, the west coast currents.关键词：wind driven circulation;FVCOM;runoff;Hedi Reservoir;river-type reservoir
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发布时间：2023-12-11 - 摘要：A method, which was constituted by humidity index (HI), Normalized Difference Vegetation Index (NDVI) and Index Based Builtup Index (IBI), was built to evaluate urban eco-environment quality based on remote sensing data and datasynthesized by principal component analysis. It was applied in Zhongshan City, Guangdong Province. The Landsat TM images in different years were used to explore the applicability and accuracy. The results showed that this method can reflect the variation of regional eco-environment quality. The eco-environment quality of Zhongshan in 1994 and 2009 was both at a good level. The overall eco-environment quality in 2009 was better than in 1994. In 2009, the area with poor eco-environment quality decreased, but the area of eco-environmental degradation increased in local region. The coordinative development degree between environment and economy was at a good level in 1994, but declined generally in 2009. Serious imbalance between eco-environment and economic development occurred in some towns.关键词：Zhongshan city;eco-environment quality assessment;GIS;coordination development degree
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发布时间：2023-12-11 - 摘要：In order to reduce economic and social loss caused by drought disaster, this paper judged the trend of drought in Guangxi based on commensurability and symmetry principle. The results showed: ① The drought disaster in Guangxi showed good commensurability, and time symmetry was very distinct. ② The butterfly structure diagram and commensurability structure system indicated a strong signal of drought disaster occurred in 2017 in Guangxi. ③ ENSO events showed a good correlation with the occurrence of drought disaster. ④ The drought disaster usually appeared in the upward section of sunspots number when the solar activity was in its accelerating stage.关键词：drought disaster;symmetry;the judgment of the trend;Guangxi
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发布时间：2023-12-11
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