最新刊期
卷 49 ， 期 1 ， 2010
- 摘要：To consider the critical growth in boundary conditions for the quasilinear problem， the main results are obtained that if "f" has superlinear but subcritical growth with respect to "u", then as p关键词：p-Laplace equation;weak solutions;critical exponent;variational principle
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发布时间：2023-12-11 - 摘要：To study the Cmax problem on manygroup jobs with one generalpurpose machinery and n specialpurpose machineries that they are with the different speeds. This problem is always NPC problem, so the approximate method is usually to be found. An improved LPT algorithm and the upper bound performance are given. The ratio of the approximate solution and the best way is T/T*≤1+1/∑〖DD(X〗i∈I〖DD)〗si, it means that the complete time using this approximate method is 1/∑〖DD(X〗i∈I〖DD)〗si more than the best in worst condition.关键词：heuristic algorithm;performance indexes;LPT algorithm;generalpurpose machinery;specialpurpose machinery
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发布时间：2023-12-11 - 摘要：Fairness is an important attribute that electronic cash transaction protocol should satisfy, as dishonesty of the transaction entity and unreliable communication are the major reasons that harm transaction fairness. Focusing on the transaction unfairness issue caused by dishonest behavior of the transaction entity, and using the methodology of undeniable conversion signature for reference, interactive confirmer mechanism to effectively solve the problem of conflict between fairness and anonymity of electronic cash transaction protocol is established. Based on improved CEMBS verifiable algorithm, a new fair electronic cash transaction protocol is proposed and its attributes are analyzed. The analysis demonstrates that the proposed protocol can effectively avoid the ambiguity of transaction while satisfying the need for fairness and anonymity.关键词：electronic cash;fair;anonymity;transaction protocol
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发布时间：2023-12-11 - 摘要：Structural damage identification based on the sensitivity technique of structural flexibility is studied. Using the Neumann series expansion, the flexibility sensitivity of the structure is firstly derived to obtain the damage detection equation. Then all the elemental damage parameters can be easily calculated by manipulating the matrix equation into a set of linear equations. Two significant advantages of the proposed flexibility sensitivity method are pointed out. The first one is that the computation of structural flexibility sensitivity is very simple and then the presented method is easily to implement. The second one is that the number of independent linear equations of the proposed method is greater than that of the previous eigenparameter sensitivity technique in most case. So damage detection results obtained by the proposed scheme will be more accurate than that obtained by the eigenparameter perturbation method. A 31-bar structure is used as a numerical example to validate the presented flexibility sensitivity method and the results are satisfactory even if noise is present. It has been shown that the proposed approach is more effective than the eigenparameter sensitivity technique and may be a promising method for structural damage detection.关键词：damage identification;modal parameter;flexibility;sensitivity
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发布时间：2023-12-11 - 摘要：After the introduction of quantified monosigned formulae, the resolution for them is investigated and proved to be sound and refutational complete. This kind of resolution can be used not only for theoretical studies but also for practical applications. As a result, a subclass of quantified monosigned formulae which can be solved the satisfiability problem in polynomial time is recognized.关键词：quantified monosigned formulae;resolution;satisfiability;in polynomial time
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发布时间：2023-12-11 - 摘要：The protocols of automatic selecting the similarity measure based on entropy for image registration is presented. Some common similarity measures based on entropy are given firstly. The accuracy, the acutance and the celerity are put forwarded as rules to select the suit measure from these measures according to the requirement of image registration. The suit similarity measure is selected automatically based on our method for the unitmodels and the multimodels of MR, CT and PET respectively in MATLAB, which is also obtained in low resolution or noise environment. The experiment results prove the feasible and validity of these protocols. The low precision of registration caused by the unsuitable similarity measure can be avoided.关键词：registration;entropy;similarity measure;rigid transformation
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发布时间：2023-12-11 - 摘要：The asymmetric Zchannel is a discrete memoryless channel with one of the input symbols transmitted with noise. The maximum a posterior probability (MAP) decoding algorithm was analyzed, and a modified decoding algorithm on the asymmetric Zchannel was deduced. Based on the algorithm, simulations on the performance of turbo codes have been carried out, and the key issues of simulations are discussed. The simulation results show that turbo codes can get excellent bit error rate performance on the asymmetric Zchannel with our proposed decoding algorithm.关键词：Z-channel;Turbo codes;MAP algorithm;decoding algorithm;bit error rate (BER)
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发布时间：2023-12-11 - 摘要：Depending on the actual service condition of subhealth bridge, the following investigation is developed: ①The concept of damage limit state is proposed, from which the subject of the serviceability carrying capacity is revealed, then the evaluation path of serviceability carrying capacity of subhealth beam is given.②The difference between the reliability of subhealth bridge and new bridge is analyzied, consequently, the problem about reasonable limit vehicle load is solved preliminarily in theory.关键词：subhealth beam bridge;damage limit state;serviceability carrying capacity;carrying vehicle load limit;reliability
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发布时间：2023-12-11 - 摘要：TiO2and La2O3doped TiO2films were deposited by means of the RadioFrequency magnetron sputtering technique. The influences of doping La2O3on the microstructure, optical properties and blood compatibility of TiO2film were investigated by using X-ray diffraction (XRD), scanning electron microscopy (SEM), UVvisible optical absorption spectroscopy and tests of platelet adhesion, respectively.Results show that doping La2O3is beneficial to the preferential growth of the (110) plane of rutile phase and can refine grain size of TiO2resulting in an increase of optical band gap from 2.85 to 3.2eV. The quantity and morphology of the adherent platelets on the surface of samples indicated that La2O3doped TiO2film is potentially useful biomaterials with good blood compatibility. The mechanism of haemocompatibility of TiO2film doped La2O3was analyzed and discussed.关键词：magnetron sputtering;TiO2film;rare earth;haemocompatibility
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发布时间：2023-12-11 - 摘要：The performance of an adaptive algorithm based on minimum BER (MBER) was superior to the one based the conventional minimum mean square error (MMSE), but the complexity is the limit on its application. A fast adaptive beamforming algorithms was proposed based on MBER, it had a low complexity and fast converge to the optimal MBER solution. More important, the proposed beamforming algorithm can obtain a better beampattern compared by the conventional MBER, which is very fit to the TDD communications system.关键词：MBER;adaptive beamforming;fast convergence rate;low complexity
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发布时间：2023-12-11 - 摘要：Based on expansion radial basis function network,one kind of new dynamic fuzzy neural network algorithm was proposed. The algorithms main feature is to maintain the fixed length of data by using glide window technology and avoid the data being saturated. The Pruning technology was used to make the network architecture unsustained growth, and avoid the fitting and the training phenomenon, thus, it has guaranteed systems panability. Finally, the approach ability of the dynamic fuzzy neural network was confirmed through the control of blood pressure. The simulation results show that the use of sliding window and pruning techniques DFNN controller has good performance.关键词：D-FNN;fuzzy rule;pruning technology;blood pressure
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发布时间：2023-12-11 - 摘要：The Changjiang Bridge in Zhongshan city is the first butterflyshape arch bridge used in highway in the world. To verify the reliability of this structure system and the rationality of design, a experimental study on mechanics behavior of this bridge under live load was carried out. Based on the measured data of static load test and the calculation results of finite element method, some problems concerned in the design of butterflyshape bridge were solved.关键词：butterflyshape arch;unsymmetrical arch rib;static load test;finite element method
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发布时间：2023-12-11 - 摘要：The three dimensional structure activity relationship was studied on a series of aminopyrazolopyridine diaryl urea VEGFR-2 tyrosine kinase inhibitors by comparative molecular field analysis (CoMFA). The results indiated that the CoMFA model had a cross validated coefficient q2 of 0681 and the relation noncross validated coefficient r2 of 0.958. The F value was 64.964. The contributions of steric and electrostatic fields to the activity were 65.7％ and 34.3％, respectively. The CoMFA model gave the basis on the structure modification of aminopyrazolopyridine diaryl urea VEGFR-2 tyrosine kinase inhibitors.关键词：three dimensional quantitative structure activity relationship (3D-QSAR);comparative molecular field analysis (CoMFA);aminopyrazolopyridine diaryl urea;VEGFR-2 tyrosine kinase inhibitors
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发布时间：2023-12-11 - 摘要：In order to investigate the effect of recycled PET(rPET) on the dynamic rheological behaviour of PP, blends of PP/rPET and compatibilized blends were prepared on a twinscrew extruder. Effects of compatibilizers and rPET contents on the dynamic rheological behaviour of PP blends were investigated. The results showed that the complex viscosity of PP/rPET blends decreased with increasing the content of rPET. Addition of PPgMA increases the complex viscosity of PET. However, addition of PPgGMA decreased the complex viscosity of PET. It indicated that chemical interaction of rPET with PPgMA was higher than that with PPgGMA. Addition of PPgMA increased the dynamic elastic modulus of PP/rPET blends. However, addition of PPgGMA decreased the dynamic elastic modulus and dynamic viscous modulus of PP/rPET blends. Addition of PPgMA decreased the mechanical loss of PP/rPET blends. However, the mechanical loss of PP/rPET blends increased at high content of PPgMA. Addition of PPgGMA increased the mechanical loss of PP/rPET blends. It was explained by the plasticization and compatibilization of PPgMA关键词：recycled PET;polypropylene;complex viscosity;dynamic elastic modulus;mechanical loss
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发布时间：2023-12-11 - 摘要：The adsorption behaviors of Cr(III)substituted heteropolyanion PW11O39Cr(III)(H2O)4- (PW11Cr) on the D301R resin were investigated. Influences of pH and temperature upon PW11Cr adsorption capacity and adsorption rate were also examined, respectively. The adsorption thermodynamic and kinetic equations were simulated and the corresponding parameters were calculated on the basis of adsorption kinetic curves and adsorption isotherms determined at different temperatures. The results showed that the adsorption capacities of PW11Cr on the resin increased with pH increasing from 2 to 8 in the aqueous solution, and decreased with the increase of temperature. The adsorption kinetics followed the pseudosecondorder regime controlled by a surface process. The rate constant k 2 that decreased with the increase of temperature was determined to be 154×10-3 g·mg-1·min-1 at 298 K. The adsorption isotherms were consistent with Freundlich model and the adsorption enthalpy calculated was about -37 kJ·mol-1, indicating a physical adsorption process.关键词：anion exchange resin D301R;Cr(III)substituted heteropolyanion;adsorption kinetics;adsorption isotherms
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发布时间：2023-12-11 - 摘要：Chlorophyll fluorescence transient kinetics of Reboulia hemisphaerica under different simulated nitrogen deposition conditions was studied. The results showed that nitrogen treatments caused changes of chlorophyll fluorescence transient of Reboulia hemisphaerica. N treatments affected PS Ⅱ by reducing the capacity of energy trap of unit area as well as changing the redox states and the heterogeneity of the filling up of the PS Ⅱ acceptor side, destroying the electron flow, especially the electron flow beyond Q-A, as a result, the absorbed energy can not be consumed in the electron flow and have to be consumed by fluorescence and heat. It can be deduced from the JIPtest that 40 and 60 kg·hm-2·a-1 treatments lead serious damages to Reboulia hemisphaerica.关键词：nitrogen deposition;chlorophyll fluorescence transient kinetics;〖WTBX〗Reboulia hemisphaerica
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发布时间：2023-12-11 - 摘要：Kucha (Camellia kucha) is a special wild tea plant containing a great amount of theacrine (1, 3, 7, 9tetramethyluric acid) besides caffeine and theobromine. Acute toxicity and sedative/hypnotic activity of Kucha were studied. The result showed that the LD50 of Kucha was more than 2150 gkg bw, suggested that the water extract of Kucha had no toxicity under our experimental conditions. Theacrine could obviously prolong the sleeping time of mice induced by pentobarbital sodium, while caffeine had the opposite exciting effect. When the contents of these two components were about similar in Kucha, no significant sedative and hypnotic effects or exciting effect was observed. However, when The contents of theacrine was 3 fold higher than that of caffeine, Kucha showed potent sedative and hypnotic properties.
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发布时间：2023-12-11 -
Spermatozoal Ultrastructure and the Main Biological Characteristics of Paracanthobrama guichenoti
摘要：The healthy male Paracanthobrama guichenoti were employed and the spermatozoa were collected from the body by artificial conduction. The sperm was observed under the scan electron microscope. Meanwhile, effects of temperature, salinity on sperm motility were studied. The results showed that: the sperm of Paracanthobrama guichenoti containing 3 parts, a head, a middlepiece and a long tail. The head is subcircle in shape. The main structure of the head is nucleus. There is no acrosome at the anterior end of the nucleus, whereas there is an implantation fossa at the posterior end of the nucleus, within which the chromatin is dense; The sleeve of the middlepiece, which is rich in mitochondria and vesicles, is connected to the posterior end of the nucleus; The tail part is slender, including principal piece and end piece. The main structure is axoneme,which is the structure of a typical “9+2”.The effects of water temperature on spermatozoa motility showed that the optimum water temperature is 24 ℃ when the spermatozoa have the longest life of span(1 900)，and the optimum range of water temperature is 20~28℃. When the salinity of water at 5‰~8‰，the spermatozoa have the best motility and the spermatozoa have the longest life span at salinity 7‰，which is 1 350 s.关键词：Paracanthobrama guichenoti;sperm;ultrastructure;biological characteristic- 1682
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发布时间：2023-12-11 - 摘要：The existing forms of cadmium (Cd) in brown rice of two cultivars, a lowCd accumulating cultivar Guangyuanzhan No3, and a highCd accumulating cultivar Zhenguiai, were studied through solvent extraction and biochemical methods. The results showed that Cd was mostly existed in brown rice in complex forms and mainly in the protein binding forms. Among the main proteins Cd was mainly bound with globular and glutelin. In comparison with Guangyuanzhan No3, Zhenguiai was higher in proportion of 01 mol/L EDTA, 25% NaCl and 02%NaOH extractableCd and had higher Cd percentage in globulin, which preliminary proved the difference between the two cultivars. Three protein absorption peaks (FI, FII and FIII) were identified in TrisHCl extraction of brown rice on Sephadex G 75. The distribution of Cd in the soluble fraction followed the same elution pattern as protein. While comparing the two rice cultivars Cd distribution in the three absorption peaks was different. In Zhenguiai the majority of soluble Cd was bounded to phytochelatins (PCs) or lowmolecularweight components with a molecular weight of ~3 kDa. However, the content of CdPCs in seed in the variety of Guangyuanzhan No3 was founded to be much lower than that in Zhenguiai, which possibly implying the difference of Cd allocation in PSC and nonPSC.关键词：existing forms;cadmium (Cd);brown rice
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发布时间：2023-12-11 - 摘要：The characters of population density, capitulum number, seed production and 1 000seed weight about Parthenium weed under different environments including crop land, grazing land, sparse forest and roadside were studied in this paper. The results showed that the characters above all of Parthenium weed under different environments were various. The population density ranged from（10±2）~（80±24）/m2, capitulum number ranged from（2 618±843）~(14 539±3 296)/m2, seed percentage range from (43.8±5.6)%~(82.5±2.2)%, seed production ranged from（10 308±1 036）~（60 361±14 661）/m2, 1 000seed weight ranged from (0.34±0.06〖DK〗)~〖DK〗(0.46±0.01) g. To the population along the roadside, the density was the maximum while seed percentage and 1 000seed weight was the minimum. In vitro, to the population distributed in crop land and sparse forest, the density was the minimum while seed percentage and 1 000seed weight was the maximum. The invasive ability and adaptation ofParthenium hysterophorusto environment were discussed in this paper according to reproductive characters.关键词：Parthenium hysterophorus;invasive environment;flowering and seed setting;reproductive characters
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发布时间：2023-12-11 - 摘要：Biodiversity has been considered at the multilevels of in landscape, ecosystem, species and genetics, respectively. How to monitor biodiversity in this multilevel is an important scope in the recent biodiversity research. This study took Shunyi District, Beijing, as a research region and analyzed the landscape pattern, community structure, species biodiversity in agriculturalforest landscape through ArcGIS software and field investigation. It indicated that the landscape patch showed characteristics of small size, large number, simple shape, low species richness and Shannon index for farmland landscape. The agriculturalforest compound landscape has higher species richness and Shannon index was higher than those in farmland. The cultivated forest has the smallest size with high variation among patches and complex shape, these traits was negative for constructing a steady forest community. As for natural forest, patches with large size and high connection resulting from human protection were positive for biodiversity, thus, the species is rich in various space. It was concluded that it is effective to combine multimethods to monitor the biodiversity of the same region from various biodiversity levels.关键词：agricultureforest biodiversity;landscape diversity;species diversity;biodiversity monitor;Shunyi District
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发布时间：2023-12-11 - 摘要：The stomach contents and food sources of Oreochromis niloticus in the mangrove and plantationaquaculture ecological coupling systems were analyzed by stable isotope tracing technology. Microscopic examination of the stomach content (n=120) has shown that the diet of adult O. niloticus is composed of organic detritus, benthic microalgae, plankton, litter fall, gastropods, bivalve and silt. The consumed items were different between the two habitats but consistent with the types of habitats they reside. Based on the stable isotope ratios of O. niloticus and the potential food sources, organic detritus, phytoplankton and litter fall were the most important assimilated food in mangrove decorated pond, and the contributions of them were 5%~55%, 10%~40% and 15%~26%, respectively. Whereas, their contributions were 8%~64%, 25%~55% and 1%~12%, respectively, in the control pond. Analysis of stomach contents and stable isotope tracing indicate that organic detritus always contributed over 50% of the food for O. niloticus in the two habitats. Our results suggest that O. niloticus are typically detritivores. Mangrove, marsh plants and phytoplankton, which are mostly grown locally in each habitat, were of minor importance in the assimilated food.关键词：Oreochromis niloticus; mangrove and plantationaquaculture ecological coupling system;food sources;stable carbon and nitrogen isotope;stomach analysis
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发布时间：2023-12-11 - 摘要：This paper presents a physically based distributed hydrological model for catchmet flood forecasting—the Liuxihe Model. This model constitutes five components including catchment dividing, evaporation, runoff production, runoff routing and parameter deriving. The catchment dividing component divides the whole catchment into grids horizontally and layers vertically. The evaporation component calculates grid evaporation based on precipitation and soil wetness. The runoff production component determines the runoff produced from each grid and divides it into surface runoff, interflow and underground water. Surface runoff is determined with the saturation excess mechanism and the interflow is determined by Campbell equation. The runoff routing component routes the runoff grid by grid over the whole catchment and divides the surface runoff routing into overland flow routing, river channel routing and reservoir routing; The parameter deriving component derives model parameters for every grid in which the parameters are divided into unadjustable parameters that are determined by the DEM and adjustable parameters adjusted with a successive procedure. A method for estimating channel cell crosssection size based on the DEM and the remote sensing imagines of the basin is also proposed, which solves the inapplicability of physically based distributed hydrological model in many basins.关键词：catchment flood forecast;physically based distributed hydrological model;runoff routing;one dimensional kinematical wave approximation;one dimensional diffusive wave approximation
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发布时间：2023-12-11 - 摘要：A packingtype microbial fuel cell (MFC) was designed to test its capability of electricity production and simultaneous biodegradation of benzene. Different experiments were conducted with the MFC using glucose, benzene, and benzene + glucose, respectively, as the fuel. Results showed that with an external resistance of 1 000 Ω, the maximal power densities of the MFC were 228 and 9.5 mW/m2 (anode), respectively, with 1 500 mg/L glucose and 1 000 mg/L benzene as the fuel (substrate). Correspondingly, the maximal volumetric power densities were 20.5 and 0.9 W/m3（calculated based on the valid net anode solution） for the glucose and benzene, respectively. When a mixed fuel of 1 000 mg/L glucose and 600 mg/L benzene was used, the maximal power density and the maximal volumetric power density were 288 mW/m2 (anode) and 25.9 W/m3, respectively. Benzene was completely degraded by the anodic microorganisms within 24 h when 1 000 mg/L glucose and 600 mg/L benzene were used as the fuel. Meanwhile, the COD removal was about 95% at the end of running cycles. For 1 500 mg/L glucose and glucosebenzene mixture, the Coulombic efficiencies of MFC were 15.7% and 2.3%, respectively. The results indicated that benzene could be used in the MFC for generating power while at the same time accomplishing biodegradation effectively. The MFC technology may provide a new method to offset treatment operating costs, making advanced remediation measure for difficultly degraded organic matters more affordable for practical applications.关键词：MFC;benzene biodegradation;electricity production
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发布时间：2023-12-11 - 摘要：The intensive hikeponds in the Pearl River Delta are taken to establish a water quality model for pond farming. The results of model verification indicate that the simulation of the model fits the real situation well and it can be used as a research tool for pond aquaculture ecosystem or as a decision support tool for the management of pond farming. The model established is used to research main factors affecting the water quality and the carrying capacity of farming ponds. Results show that DO is generated mainly from phytoplankton photosynthesis and artificial oxygen enhancement, and consumed mainly by fish respiration. DO contents are influenced by various factors. TAN and SRP are generated mainly from fish metabolization and consumed mainly by absorption of phytoplanktons. They change much slowly compared with DO. The farming capacity of the farming ponds is influenced by many factors, including internal factors such as feed digestion and utilization and external factors such as the DO level and the TAN accumulation. The farming capacity of the mainly farmed fish increases with the increase of feed digestion rate and is restricted by the lack of DO and the high TAN concentration. The farming capacity of secondarily farmed fish increases with increasing availability of the heterotrophic feed caused by the decrease of digestion of feed for mainly farmed fish，and is restricted by the lack of DO. Mixed, rotational fishing model makes full exploitation of farming space, which can further extend the farming capacity in fish ponds.关键词：farming pond;water quality model;hikepond;the Pearl River Delta
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发布时间：2023-12-11 - 摘要：This study applied the HilbertHuang Transform (HHT) in the multipletimescales analysis of annual runoff series in the Yarlung Zangbo River. With the measured annual runoff data from 1956 to 2000 in the Yarlung Zangbo River, the Intrinsic Mode Function (IMF) and Hilbert spectrum were used to extract hydrological time series periods and the evolution trends of the natural annual runoff. The results showed that the annual runoff periods of the Yarlung Zangbo River include 3, 6~8, 9,11~13,16~17 and 22~24 years, respectively. It indicated that the annual runoff of the main and tributary of the Yarlung Zangbo river had an obvious decline trend during 1960s and reached the minimum in 1980s. since then, the annal runoff increased and a relatively wet season occurred in 1990s.关键词：the Yarlung Zangbo River;HilbertHuang Transform;runoff;periodic variation;evolution trend
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发布时间：2023-12-11 - 摘要：Five surface water samples, 32 soil samples and 14 groundwater samples have been taken from the representative area of the Pearl River Delta, in order to understand arsenic origin and distribution in water and soil of this area. The results show that surface water in this area has suffered arsenic pollution. Total arsenic content of topsoil (0-10cm) is from 19.8 to 27.4 mg/kg, with an average value of 23.7 mg/kg. The most of arsenic content in topsoil is residual fraction. The sequence of arsenic average content of seven forms in topsoil is residual fraction＞weak organic fraction＞oxide fraction＞carbonate fraction＞strong organic fraction＞water soluble fraction＞ion exchange fraction. Total arsenic content of subsoil (30-40cm) is from 11.5mg/kg to 28.1 mg/kg, with an average value of 21.2 mg/kg. The most of arsenic content in subsoil also is residual fraction. The sequence of arsenic average contents of seven forms in subsoil is residual fraction＞weak organic fraction＞oxide fraction＞carbonate fraction＞strong organic fraction＞ion exchange fraction＞water soluble fraction. Average contents of all arsenic forms are higher in topsoil than in subsoil. In unsaturated zone, total arsenic content decreaseds firstly and then increases with the depth. The contents of water soluble fraction, ion exchange fraction and carbonate fraction decrease gradually with the depth. The contents of weak organic fraction, oxide fraction, strong organic fraction and residual fraction do not show regular variation with the depth.The arsenic content of groundwater is from 00028 to 0.021mg/L, with an average value of 0.0114mg/L. The arsenic content exceeds 42.9% compared with the Chinese drinking water quality standards(0.01mg/L). Industrial wastewater infiltration and original arsenic released from aquifer medium are the main origin of arsenic in groundwater.关键词：the Pearl River Delta;water and soil;arsenic;fraction;distribution
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发布时间：2023-12-11 - 摘要：In this study, a mesoscale model (MM5) is used to simulate the impact of land use change on monthly climate in summer over the Pearl River Delta (PRD) region. The simulated period of time is June in 2005. The simulated results show that the simulated monthly average 2m temperature and monthly precipitation correspond to those observed in domain D02. The simulated monthly mean 2m temperature in the PRD increases and a heat island effect become distinctly strong. Due to the urban expansion, the precipitation in Guangzhou, Foshan and Jiangmen increases, whereas the precipitation decreases in Dongguan, Zhuhai and Shenzhen.关键词：urban heat island effect;landuse change;the Pearl River Delta region
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发布时间：2023-12-11 - 摘要：The volatile oils were prepared from Calendula officinalis by headspace liquid phase microextraction (HSLPME) and steam distillation (SD). Their constituents were analyzed and identified by gas chromatographymass spectrometry combined with computer retrieval, and were quantified by calculating the relative contents basing on the peak areas normalization method. The results showed that fifteen components were identified for the volatile oil extracted by HS-LPME, and thirtyone components were identified for that extracted by SD. However, the main components obtained from both methods were found to be quite similar. Among the fourteen mutual components, α-cadinol, τ-Muurolol, τ-cadinene, δ-cadinene, α-muurolene were the main components, occupied 93.43% and 87.18% of the total volatile oils prepared by HS-LPME and SD, respectively. It was also observed that there were no significant differences in the relative contents of these five components between the two methods.关键词：Calendula officinalis (Pot Marigold);volatile oil;steam distillation;headspace liquid phase microextraction;GC-MS
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发布时间：2023-12-11
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