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1Seedling growth and metal accumulation of selected woody species in copper and lead/zinc mine tailings显示文摘A greenhouse pot experiment was conducted to evaluate the potential of selected woody plants for revegetation in copper (Cu) and lead/zinc (Pb/Zn) mine tailing areas.Five woody species (Amorpha fruticosa Linn,Vitex trifolia Linn.var.simplicifolia Cham,Glochidion puberum (Linn.) Hutch,Broussonetia papyrifera,and Styrax tonkinensis) and one herbaceous species (Sesbania cannabina Pers) were planted in Cu and Pb/Zn tailings to assess their growth,root morphology,nutrition uptake,metal accumulation,and translocation in plants.Amorpha fruticosa maintained normal growth,while the other species demonstrated stress related growth and root development.Sesbania cannabina showed the highest biomass among the plants,although it decreased by 30% in Cu tailings and 40% in Pb/Zn tailings.Calculated tolerance index (TI) values suggested that A.fruticosa,an N-fixing shrub,was the most tolerant species to both tailings (TI values 0.92-1.01),while S.cannabina had a moderate TI of 0.65-0.81 and B.papyrifera was the most sensitive species,especially to Pb/Zn tailings (TI values 0.15-0.19).Despite the high concentrations of heavy metals in the mine tailings and plants roots,only a small transfer of these elements to the aboveground parts of the woody plants was evident from the low translocation factor (TF) values.Among the woody plants,V.trifolia var.simplicifolia had the highest TF values for Zn (1.32),Cu (0.78),and Pb/Zn (0.78).The results suggested that A.fruticosa and S.cannabina,which have the highest tolerance and biomass production,respectively,demonstrated the potential for tailings revegetation in southern China.Xiang Shi Xiaolei Zhang Guangcai Chen Yitai Chen Ling Wang Xiaoquan Shan 2011Journal of Environmental Sciences2011,23,2:18
2Similarity criteria and coal-like material in coal and gas outburst physical simulation显示文摘Bo Zhao Guangcai Wen Haitao Sun Dongling Sun Huiming Yang Jie Cao Linchao Dai Bo Wang 2018International Journal of Coal Science & Technology2018,5,2:17
3Characteristics of change in water quality along reclaimed water intake area of the Chaobai River in Beijing, China显示文摘To reveal the basic characteristics and controlling factors of water quality change in the project Wenyu to Chaobai reclaimed water diversion, the water quality in the study area was monitored for one year at seven monitoring sites. Inverse geochemical models of the statistical groups were developed using PHREEQC to elucidate the hydrochemistry characteristics of reclaimed water and the factors. The monitoring results indicated that nitrogen and phosphorus contents were significantly reduced along the river mainly caused by seasonal and location variation. The pH ranged from 7.44 to 9.81. Photosynthesis of algae and denitrification in anaerobic microenvironment ultimately led to a sudden p H increase after the Jian River and the Chaobai River confluence. Mg^(2+)and SO_4^(2-) levels dropped obviously in the summer and increased in winter seasons after intersection. Na+and Cl-are relatively stable, and marked drop in the concentration only after the two rivers meet. And there is a decrease of Ca^(2+) and HCO^(3-) and increase in CO_3^(2-) during monitoring period. As a whole, the primary ions and nutrient components, including nitrogen and phosphorus, had high levels in winter. Algae's photosynthesis and respiration were observed to have an impact on the river water quality; there was precipitation–dissolution of minerals and denitrification from upstream to downstream. Inverse geochemical PHREEQC modeling confirmed that there was precipitation of aragonite or calcite, and gypsum or anhydrite in summer, and dissolution in winter; as well as precipitation of dolomite in winter, and cationic exchange and denitrification along the river.Lei Yang Jiangtao He Yumei Liu Jian Wang Lie Jiang Guangcai Wang 2016Journal of Environmental Sciences2016,28,12:14
4Crop 3D a LiDAR based platform for 3D high-throughput crop phenotyping显示文摘With the growing population and the reducing arable land, breeding has been considered as an effective way to solve the food crisis.As an important part in breeding, high-throughput phenotyping can accelerate the breeding process effectively. Light detection and ranging(LiDAR) is an active remote sensing technology that is capable of acquiring three-dimensional(3 D) data accurately,and has a great potential in crop phenotyping. Given that crop phenotyping based on LiDAR technology is not common in China,we developed a high-throughput crop phenotyping platform, named Crop 3 D, which integrated LiDAR sensor, high-resolution camera, thermal camera and hyperspectral imager. Compared with traditional crop phenotyping techniques, Crop 3 D can acquire multi-source phenotypic data in the whole crop growing period and extract plant height, plant width, leaf length, leaf width, leaf area, leaf inclination angle and other parameters for plant biology and genomics analysis. In this paper, we described the designs,functions and testing results of the Crop 3 D platform, and briefly discussed the potential applications and future development of the platform in phenotyping. We concluded that platforms integrating LiDAR and traditional remote sensing techniques might be the future trend of crop high-throughput phenotyping.Qinghua Guo Fangfang Wu Shuxin Pang Xiaoqian Zhao Linhai Chen Jin Liu Baolin Xue Guangcai Xu Le Li Haichun Jing Chengcai Chu 2018Science China(Life Sciences)2018,61,3:14
5Groundwater hydrochemistry and isotope geochemistry in the Turpan Basin, northwestern China显示文摘The Turpan Basin is located in the arid zone of northwestern China and is a typical closed inland basin surrounded by high mountains. It is one of the most arid regions in the world and, as a result, the groundwater in this area is very important for both domestic and agricultural uses. In the present study, the relationships of major elements(K+, Na+, Ca2+, Mg2+, HCO3-, SO42- and Cl-) and environmental isotopes(δ18O, δ2H and T) in groundwater were analyzed to investigate the evolution of the regional hydrochemistry within the Turpan Basin. The hydrochemistry results demonstrate that groundwater with high total dissolved solids(TDS) concentration is dominated by sodium chloride(Na-Cl) and sodium sulfate(Na-SO4) type water, whereas that with low TDS concentration(typically from near mountain areas) is dominated by calcium bicarbonate(Ca-HCO3) type water. The evolution of groundwater hydrochemistry within the Turpan Basin is a result of calcium carbonate precipitation, evaporation concentration, cation exchange and dissolution of evaporites(i.e. halite, mirabilite and gypsum). Furthermore, evaporite dissolution associated with irrigation practice plays a key role in the groundwater salinization, especially in the central part of the basin. Environmental isotopes reveal that the groundwater is recharged by precipitation in the mountain areas and fast vertical infiltration of irrigation return flow. In the southern sub-basin the shallow groundwater and the deep groundwater is separated at a depth of about 40 m, with substantial differences in terms of hydrochemical and isotopic characteristics. The results are useful for decision making related to sustainable water resource utilization in the Turpan Basin and other regions in northwestern China.Lu CHEN GuangCai WANG FuSheng HU YaJun WANG Liang LIU 2014Journal of Arid Land2014,6,4:13
6Object Detection Research of SAR Image Using Improved Faster Region-Based Convolutional Neural Network显示文摘Target detection technology of synthetic aperture radar(SAR)imageis widely used in the field of military reconnaissance and surveillance.The traditional SAR image target detection methods need to be provided a lot of empirical knowledge because the characteristics of SAR images in different configurations(attitude,pitch angle,imaging parameters,etc.)will change greatly,resulting in high generalization error.Currently,deep learning method has achieved great success in the field of image processing.Research shows that deep learning can achieve a more intrinsic description of the data,while the model has a stronger ability of modeling and generalization.In order to solve the problem of insufficient data in SAR data sets,an experimental system for acquiring SAR image data in real scenes was built.Then the transfer learning method and the improved convolution neural network algorithm(PCA+Faster R-CNN)are applied to improve the target detection precision.Finally,experimental results demonstrate the significant effectiveness of the proposed method.Long SUN Tao WU Guangcai SUN Dazheng FENG Lieshu TONG Mengdao XING 2020Journal of Geodesy and Geoinformation Science2020,3,3:13
7Effects of sulfur fertilization and short-term high temperature on wheat grain production and wheat flour proteins显示文摘The content of wheat flour proteins affects the quality of wheat flour. Sulfur nutrition in wheat can change the protein content of the flour. The inconsistency and instability of wheat grain quality during grain filling under high temperature stress(HTS) are a major challenge to the production of high-quality wheat. The effects of sulfur fertilization and HTS on wheat flour protein and its components are unknown. In this study, treatments varying two factors: sulfur fertilization and exposure to short-term HTS, at 20 days postanthesis, were applied to two wheat cultivars with differing gluten types. Plants of a stronggluten wheat(Gaoyou 2018) and a medium-gluten wheat(Zhongmai 8) were grown in pots in Beijing in 2015–2017. HTS significantly increased the contents of total protein, albumin,gliadin, glutenin, Cys, and Met in wheat kernels, but reduced grain yield, grain weight,protein yield, globulin content, and total starch accumulation. The HTS-induced increase in total protein amount was closely associated with nitrate reductase(NR) and glutamine synthetase(GS) activities in flag leaves. Sulfur fertilization increased grain and protein yields; grain weight; total protein, albumin, gliadin, glutenin, and globulin contents; protein yield; total starch; Cys, Met; and NR and GS activities. HTS and sulfur fertilization had larger effects on the strong-than on the medium-gluten cultivar. Sulfur fertilization also alleviated the negative effects of HTS on grain yield, protein yield, and starch content.Thus, growing wheat with additional soil sulfur can improve the quality of the flour.Zhiqiang Tao Xuhong Chang Demei Wang Yanjie Wang Shaokang Ma Yushuang Yang Guangcai Zhao 2018The Crop Journal2018,6,4:11
8Multi-drug Resistance and Characteristic of Integrons in Shigella spp.Isolated from China显示文摘Objective To investigate the characteristic of integrons and the relationship between integrons and antimicrobial resistance in Shigella spp. Methods Ninety Shigella strains (83 S. flexneri and 7 S. sonnei) were isolated from the stools of patients in China. Susceptibility to 8 antimicrobials was tested for all isolated strains. PCR, RFLP and sequencing analysis of integrons were applied to all of them. Results High prevalence of multi‐drug resistance (95.6%) was identified. Of the isolates 79 (87.8%) carried integrase genes of class 1 integron (3.3%), class 2 integron (10.0%) or both (74.4%). No intI3 was detected in the tested isolates. The prevalence of intI2 was significantly higher in isolates with multi‐drug resistance to at least 3 antibiotics than that in isolates with resistance to 2 and less antibiotics (P<0.05). Gene cassettes dfrA17‐aadA5, dfrA12‐orfF‐aadA2 of class 1 integron and dfrA1‐sat1‐aadA1 of class 2 integron were identified. Conclusion The class 2 integron may play a role in the emergence of multi‐drug resistance in Shigella spp.ZHU JingYuan DUAN GuangCai YANG HaiYan FAN QingTang XI YuanLin 2011Biomedical and Environmental Sciences2011,24,1:11
9Oxygen and Hydrogen Isotopes of Waters in the Ordos Basin,China:Implications for Recharge of Groundwater in the North of Cretaceous Groundwater Basin显示文摘从 1988 年 1 月在 Ordos 盆从气象学的车站收集到 2005 年 12 月的几百件降水样品被用来建立一根本地大气的水线并且计算现代降水的加权的平均同位素的作文。氧和氢同位素,与为 δ 18 分别地, O 和 δD 在春天在冬季和富人被弄空,并且逐渐地在夏天和秋天减少,说明季节的效果是可观的。他们也证明南方部分和 Ordos 盆的北方部分之间的同位素的差别不是明显的,并且在中间的部分的同位素通常被弄空。32 件样品的同位素作文从浅地下水收集了(不到 150 m 的深度) 在到有为 δ 18 O 并且从 85 ‰到有为 δD 的 63 ‰的一般水准的 46 ‰。他们中的大多数与现代降水是相同的。22 中间、深的地下水的同位素作文(比 275 m 的深度大) 为 δ 18 O 并且从 89 ‰到有为 δD 的 76 ‰的一般水准的 63 ‰。一般水准珍视,说明是显著地不到那些现代降水中间、深的地下水在比较地更低的空气温度被再装。14 C 证明中间、深的地下水的 recharge 在迟了的更新世开始了。从八个湖收集的 13 件湖水样品的同位素定义一个本地蒸发趋势,与 3.77 的一个相对扁平的斜坡,并且证明湖水被现代降水和浅地下水主要喂。YANG Yuncheng SHEN Zhaoli WENG Dongguang HOU Guangcai ZHAO Zhenhong WANG Dong PANG Zhonghe 2009Acta Geologica Sinica(English Edition)2009,83,1:10
10Narrow-band radar imaging of spinning targets显示文摘According to the characteristics of narrow-band radar echoes from spinning targets,this paper applies the complex-valued back-projection method to image formation.Since it accumulates the sinusoidal phase of spinning scatterers effectively,this method can obtain high resolution imaging.The resolution and required radar pulse repetition frequency (PRF) of this method are deduced.For imaging of fast spinning targets,however,spurious peaks appear due to azimuth down sampling with a low PRF.Therefore,a signal model of azimuth down-sampled echoes is created according to the compressed sensing (CS) theory.Then an imaging method based on orthogonal matching pursuit (OMP) is proposed according to the sparsity nature of ISAR echoes.Finally,the effectiveness of the proposed methods is demonstrated using simulated data.BAI XueRu SUN GuangCai WU QiSong XING MengDao BAO Zheng 2011Science China(Information Sciences)2011,54,4:9
11Effects of tridimensional uniform sowing on water consumption, nitrogen use, and yield in winter wheat显示文摘Wheat is a staple crop worldwide, but yields may diminish as climate change causes increasingly unpredictable patterns of precipitation and soil nutrient availability. Farmers are thus challenged to maximize planting efficiency to increase yield, while also improving their resource use efficiency. In this study the effectiveness of tridimensional uniform sowing was tested across a range of planting densities for winter wheat crops on the North China Plain. Tridimensional uniform sowing was tested against conventional drilling at three planting densities (180 × 104, 270 × 104, and 360 × 104 plants ha 1) and assessed for water consumption, biomass, nitrogen uptake and allocation, and aspects of yield. The tridimensional uniform sowing treatment outperformed the conventional drilling treatment in most metrics and at most planting densities, while performing markedly better at higher planting densities. Water consumption decreased and nitrogen efficiency increased. Tiller number and percentage of productive tillers, leaf area index, dry weight, and yield increased without a significant decline in grain protein. Nitrogen allocation was more efficient under tridimensional uniform sowing than with conventional drilling, and also varied according to annual precipitation and planting density. Both yield and grain protein contents were significantly correlated with the amount of pre-anthesis accumu- lated nitrogen translocated from vegetative organs to kernels after anthesis. Overall, a density of 270 × 104 plants ha 1 provided the highest water use efficiency and grain yield. Tridimensional uniform sowing will benefit farmers by forming stronger overall crops, promoting the coordinated improvement of yield, nitrogen uptake and efficiency, and increasing grain protein content at higher planting densities.Zhiqiang Tao Shaokang Ma Xuhong Chang Demei Wang Yanjie Wang Yushuang Yang Guangcai Zhao Jiancang Yang 2019The Crop Journal2019,7,4:8
12Temperature pattern dynamics in shocked porous materials显示文摘The physical fields in porous materials under strong shock wave reaction are very complicated. We simulate such systems using the grain contact material point method. The complex temperature fields in the material are treated with the morphological characterization. To compare the structures and evolution of characteristic regimes under various temperature thresholds, we introduce two concepts, structure similarity and process similarity. It is found that the temperature pattern dynamics may show high similarity under various conditions. Within the same material, the structures and evolution of high-temperature regimes may show high similarity if the shock strength and temperature threshold are chosen appropriately. For process similarity in materials with high porosity, the required temperature threshold increases parabolically with the impact velocity. When the porosity becomes lower, the increasing rate becomes higher. For process similarity in different materials, the required temperature threshold and the porosity follow a power-law relationship in some range.XU AiGuo*, ZHANG GuangCai, LI Hua, YING YangJun, YU XiJun & ZHU JianShi National Key Laboratory of Computational Physics, Institute of Applied Physics and Computational Mathematics, Beijing 100088, China 2010Science China(Physics,Mechanics & Astronomy)2010,53,8:7
13Active Fault Exploration and Seismic Hazard Assessment in Fuzhou City显示文摘It has been proven by a number of earthquake case studies that an active fault-induced earthquake beneath a city can be devastating. It is an urgent issue for seismic hazard reduction to explore the distribution of active faults beneath the urban area and identify the seismic source and the risks underneath. As a pilot project of active fault exploration in China, the project, entitled “Active fault exploration and seismic hazard assessment in Fuzhou City', started in early 2001 and passed the check before acceptance of China Earthquake Administration in August 2004. The project was aimed to solve a series of scientific issues such as fault location, dating, movement nature, deep settings, seismic risk and hazard, preparedness of earthquake prevention and disaster reduction, and etc. by means of exploration and assessment of active faults by stages, i.e., the preliminary survey and identification of active faults in target area, the exploration of deep seismotectonic settings, the risk evaluation of active seismogenic faults, the construction of geographic information system of active faults, and so on. A lot of exploration methods were employed in the project such as the detection of absorbed mercury, free mercury and radon in soil, the geological radar, multi-channel DC electrical method, tsansient electromagnetic method, shallow seismic refraction and reflection, effect contrast of explored sources, and various sounding experiments, to establish the buried Quaternary standard section of the Fuzhou basin. By summing up, the above explorations and experiments have achieved the following results and conclusions: (1)The results of the synthetic pilot project of active fault exploration in Fuzhou City demonstrate that, on the basis of sufficient collection, sorting out and analysis of geological, geophysical and borehole data, the best method for active fault exploration (location) and seismic risk assessment (dating and characterizing) in urban area is the combination of various approaches, that is, the possible location of active fault determined by using geochemical exploration as a guide “scout', the shallow seismic sounding as the main tool, the electromagnetic method as a supplement, establishing the standard Quaternary profile or stratigraphic sequence from drilling and various geophysical parameters from borehole logs as methods to correct and verify the data above. And in addition, the method also includes the field surveys on fault exposures, trenching, paleoearthquake investigation, dating and comparison of lithology, strata sequence, absolute or relative ages of the cores on the two sides of buried faults. (2)The Fuzhou basin locates under the regional seismotectonic settings which have the potential of moderate earthquake. Comparatively, the region is less affected by the “Taiwan dynamic Antenna'; (3)The activity of the major faults in Fuzhou basin is weak in general. All the six identified target faults are not Holocene faults, among which the Bayi Reservoir-Shanggan fault and the Minhou-Nanyu fault are dormant at least since the mid Epipleistocene time, and the rest are dormant since the Epipleistocene time; (4)In terms of deep-seated structures beneath the basin, there is no evidence indicating the possible occurrence of the underneath strong destructive earthquakes. The adjacent Changle-Zhao’an fault zone is the potential seismic source which may possibly affect Fuzhou City; (5)There exists potential of moderate-strong earthquake on the major faults of the region, but the probability is low; (6)The seismic hazards are weak in the region and the surface earthquake fractures are not likely to occur; (7)The first geographic information system of active faults is developed with functions of information query and display, data management, analysis and processing, etc.Zhu Jinfang Huang Zonglin Xu Xiwei Zheng Rongzhang Fang Shengmin Bai Denghai Wang Guangcai Min Wei Wen Xueze Han Zhujun 2005Earthquake Research in China2005,19,3:7
14Design of synthetic aperture radar low-intercept radio frequency stealth显示文摘Not confined to a certain point,such as waveform,this paper systematically studies the low-intercept radio frequency(RF)stealth design of synthetic aperture radar(SAR)from the system level.The study is carried out from two levels.In the first level,the maximum low-intercept range equation of the conventional SAR system is deduced firstly,and then the maximum low-intercept range equation of the multiple-input multiple-output SAR system is deduced.In the second level,the waveform design and imaging method of the low-intercept RF SAR system are given and verified by simulation.Finally,the main technical characteristics of the lowintercept RF stealth SAR system are given to guide the design of low-intercept RF stealth SAR system.CHANG Wensheng TAO Haihong LIU Yanbin SUN Guangcai 2020Journal of Systems Engineering and Electronics2020,31,1:7
15Complete three-dimensional coseismic displacements due to the 2021 Maduo earthquake in Qinghai Province,China from Sentinel-1 and ALOS-2 SAR images显示文摘On 22 nd May 2021(local time),an earthquake of M_(s)7.4 struck Maduo county in Qinghai Province,China.This was the largest earthquake in China since the 2008 Wenchuan earthquake.In this study,ascending/descending Sentinel-1 and advanced land observation satellite-2(ALOS-2)synthetic aperture radar(SAR)images were used to derive the three-dimensional(3-D)coseismic displacements of this earthquake.We used the differential interferometric SAR(In SAR,DIn SAR),pixel offset-tracking(POT),multiple aperture In SAR(MAI),and burst overlap interferometry(BOI)methods to derive the displacement observations along the line-of-sight(LOS)and azimuth directions.To accurately mitigate the effect of ionospheric delay on the ALOS-2 DIn SAR observations,a polynomial fitting method was proposed to optimize range-spectrum-split-derived ionospheric phases.In addition,the 3-D displacement field was obtained by a strain model and variance component estimation(SM-VCE)method based on the high-quality SAR displacement observations.Results indicated that a left-lateral fault slip with the largest horizontal displacement of up to 2.4 m dominated this earthquake,and the small-magnitude vertical displacement with an alternating uplift/subsidence pattern along the fault trace was more concentrated in the near-fault regions.Comparison with the global navigation satellite system data indicated that the SM-VCE method can significantly improve the accuracy of the displacements compared to the classical weighted least squares method,and the incorporation of the BOI displacements can substantially benefit the accuracy of north-south displacement.In addition to the displacements,three coseismic strain invariants calculated based on the strain model parameters were also investigated.It was found that the eastern and western parts of the faults suffered more significant strains compared with the epicenter region.Jihong LIU Jun HU Zhiwei LI Zhangfeng MA Lixin WU Weiping JIANG Guangcai FENG Jianjun ZHU 2022Science China Earth Sciences2022,65,4:6
16Endothelial activation and dysfunction in COVID-19:from basic mechanisms to potential therapeutic approaches显示文摘On 12 March 2020,the outbreak of coronavirus disease 2019(COVID-19)was declared a pandemic by the World Health Organization.As of 4 August 2020,more than 18 million confirmed infections had been reported globally.Most patients have mild symptoms,but some patients develop respiratory failure which is the leading cause of death among COVID-19 patients.Endothelial cells with high levels of angiotensin-converting enzyme 2 expression are major participants and regulators of inflammatory reactions and coagulation.Accumulating evidence suggests that endothelial activation and dysfunction participate in COVID-19 pathogenesis by altering the integrity of vessel barrier,promoting pro-coagulative state,inducing endothelial inflammation,and even mediating leukocyte infiltration.This review describes the proposed cellular and molecular mechanisms of endothelial activation and dysfunction during COVID-19 emphasizing the principal mediators and therapeutic implications.Yuefei Jin Wangquan Ji Haiyan Yang Shuaiyin Chen Weiguo Zhang Guangcai Duan 2020Signal Transduction and Targeted Therapy2020,5,1:6
17Coseismic response of groundwater level in the Three Gorges well network and its relationship to aquifer parameters显示文摘The 12 May 2008 Ms 8.0 Wenchuan earthquake caused notable changes in the water levels of wells in the Three Gorges area. This work examines the relationship between these coseismic changes in water level and the changes in aquifer parameters. Three wells in the area with good responses to earth tide were chosen for analysis. Water-level data from February to June 2008 were used to calculate the aquifer transmissivity, permeability and specific storage of the rocks, and analyze the relationship between the coseismic responses of the wells and their aquifer parameters. The results show that the Wenchuan earthquake changed these parameters considerably, thereby controlling co- and postseismic variations of water level. The values of these parameters prior to the earthquake are linearly related with the amplitudes of coseismic variations in water level. The larger the aquifer transmissivity, the more remarkable the coseismic change in water level. During the earthquake, changes in aquifer parameters were found to be associated with coseismic variations in water level, with the larger changes occurring when the coseismic variation in water level was larger. The tectonic setting has a certain degree of influence on the co- and postseismic changes in water level. The permeability structures of the fault zone appear to determine the manner of coseismic variation in water level. Moreover, it seems that the water level in wells where groundwater converges more easily can recover faster following an earthquake. Insight from this study helps to improve understanding of the characteristics of water-level changes caused by earthquakes.SHI ZheMing WANG GuangCai LIU ChengLong MEI JianChang WANG JinWei FANG HuiNa 2013Chinese Science Bulletin2013,58,25:6
18Parameter estimation of moving targets in the SAR system with a low PRF sampling rate显示文摘In the synthetic aperture radar(SAR)system with low pulse repetition frequency(PRF)sampling,it is difficult for the motion parameters estimation of the moving targets,because of the Doppler spectrum ambiguity and Doppler centroid frequency ambiguity of the echo signals.Considering that moving targets are sparsely distributed in the observed scene,their positions and velocities can be reconstructed by using the compressed sensing(CS)technique.In this paper,the range-walk correction are implemented by the Keystone transform and the sparse range-walk correction(SRWC),then the CS technique is proposed to reconstruct motion parameters by processing the azimuth signals of the moving targets.Experiments using the simulated and real data are performed,and the results confirm the validity of the proposed method.LIU Yan WU QiSong SUN GuangCai XING MengDao LIU BaoChang BAO Zheng 2012Science China(Information Sciences)2012,55,2:5
19Effects of metal cations on sorption-desorption of p-nitrophenol onto wheat ash显示文摘The mutual effects of metal cations(Cu2+,Pb2+,Zn2+,and Cd2+) and p-nitrophenol(NP) on their adsorption desorption behavior onto wheat ash were studied.Results suggested that Cu2+,Pb2+,and Zn2+ diminished the adsorption and increased the desorption of NP remarkably,while Cd2+ had no such effect.In contrast,NP diminished the adsorption of Cu2+,Pb2+,and Zn2+ onto ash,however,this suppression effect depended on the initial concentrations of metal cations.NP had no effect on Cd2+ adsorption on ash.Fourier transform infrared(FT-IR) and X-ray absorption spectroscopic(XAS) studies suggested the following mechanisms responsible for the metal suppression effect on NP adsorption:(1) large hydrated Cu2+,Pb2+,and Zn2+ shells occupied the surface of ash and prevent nonspecific adsorption of NP onto ash surface;(2) Cu2+,Pb2+,and Zn2+ may block the micropores of ash,resulting in decreased adsorption of NP;(3) complexation of Cu2+,Pb2+,and Zn2+ was likely via carboxyl,hydroxylic and phenolic groups of wheat ash and these same groups may also react with NP during adsorption.As a 'soft acid',Cd2+ is less effcient in the complexation of oxygencontaining acid groups than Cu2+,Pb2+,and Zn2+.Thus,Cd2+ had no effect on the adsorption of NP on wheat ash.YushengWang Zhiguo Pei Xiaoquan Shan Guangcai Chen Jing Zhang Yaning Xie Lirong Zheng 2011Journal of Environmental Sciences2011,23,1:5
20Groundwater Systems and Resources in the Ordos Basin,China显示文摘Ordos 盆是在西北的中国的大规模沉积的盆。到顶的从底部的 hydrostratigraphic 单位是 pre 寒武纪的变形岩石,更低的古生代的碳酸盐岩石,上面对中生代碎屑状的岩石和新生代存款古生代。全部的厚度直到 6000 m。三个地下水系统在 Ordos 盆是在场的,基于地质的设置,即石灰岩地区常见的地形地下水系统,白垩纪碎屑状的地下水系统和第四级的地下水系统。这份报纸系统地描述每个系统的地下水流动模式和对地下水资源的全面评价。HOU Guangcai LIANG Yongping SU Xiaosi ZHAO Zhenghong TAO Zhengping YIN Lihe YANG Yuncheng WANG Xiaoyong 2008Acta Geologica Sinica(English Edition)2008,82,5:5
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