面向GF-5卫星高光谱传感器的浑浊水体叶绿素a浓度反演算法研究——以鄱阳湖为例

为了分析即将发射的高分5号卫星(GF-5)的高光谱数据在内陆水体水色遥感中的应用潜力,以鄱阳湖为研究区域,利用2009年、2011年和2016年共134组现场实测光谱及其对应的叶绿素a、总悬浮物浓度数据,考虑高浑浊水体引起的叶绿素a浓度变化的光谱响应差异,在进行水体光学分区基础上通过光谱模拟与差分处理开展了叶绿素a浓度跨阶分高光谱反演研究.结果表明：1)进行光学分区有利于提高反演精度,非高浑浊水体(NDCI≥0.06)区域,反演模型判定系数R2达到0.82,均方根误差RMSE为1.12,平均相对误差MRE为0.32,而不进行光学分区的全湖区反演建模R2仅为0.37;2) 相较于鄱阳湖前期研究得到的最优多波段反演模型(R2＝0.76),利用495、591、675、679、684、688、692和696 nm等波长的原始光谱以及差分光谱(一阶差分、二阶差分)建立的跨阶分多波段组合模型可以更有效地反演非高浑浊水体叶绿素a浓度(R2＝0.82),但对于高浑浊水体(NDCI<0.06),叶绿素a浓度的高光谱反演能力还需要进一步挖掘.     

基于分析模型的太湖水色参数敏感度分析

文中以Gordon生物光学模型为基础,利用2004年10月实测的太湖水体固有光学特征、表观光学特征和水体组份浓度数据,构建了参数化的分析模型.基于分析模型,在400 ～ 700 nm可见光光谱的范围内,分别对无机悬浮物、有机悬浮物、叶绿素和黄色物质的光谱敏感程度进行了定量分析,重新认识了水色光谱的形成机理.最后,对进一步利用分析模型构建反演模型的关键问题进行了总结.     

鄱阳湖丰水期水体后向散射特性研究

后向散射是获取湖泊水体光学活性物质遥感信息的关键,针对无机悬浮物为主的浑浊二类水体, 其对水体表观光学性质有着决定性的影响,研究表层水体后向散射特性在提高湖泊光学活性物质遥感反演精度方面具有重要的意义.该文通过2017年6月在鄱阳湖丰水期36个站点的巡航监测,分析了水体后向散射特征及其与光学活性物质的关系,并利用指数模型对后向散射系数进行参数化.研究结果表明：在420～700 nm波段范围内,水体后向散射系数、后向散射概率随波长的变动趋势较为一致,均随着波长的增大呈指数函数减小;空间上水体后向散射系数的均值和变幅为南湖区>主湖区>北湖区;总悬浮颗粒物浓度与后向散射系数之间的相关性随波长增大而增大,其中700 nm波段的相关性最好,R2达到0.760;随着波长的增加后向散射系数与叶绿素a含量的相关性减少;同时建立了后向散射系数光谱模型,斜率指数为1.229,470～700 nm波段平均绝对百分比误差均小于8%,具有较好的反演精度.     

［Ni(phen) 3］2［Ni(PO4)2(H2PO4)6(OH)6(MoO2)12］的合成和晶体结构

利用中温水热技术合成一种新型还原型钼磷酸盐： ［Ni(phen) ₃］₂［Ni(PO₄)₂(H₂PO₄)6(OH)₆(MoO₂)₁₂］(phen: 邻菲啰啉), 并通过单晶X射线衍射技术测定了该化合物的晶体结构.该化合物属于三斜晶系, P1空间群, 晶胞参数: a=1.404 2(3) nm, b=1.405 0(3) nm, c=1.408 2(3) nm, α=74.53(3)°, β=74.72(3)°,γ=74.81(3)°, V=2.527 6(9) nm3, Z=1, R1=0.076 2, wR2=0.168 6.     

上海公园绿地景观水体透明度影响因子研究

于2010年,以上海市90个公园绿地共107个景观水体为研究对象,通过野外调查与室内分析,探寻水体透明度与光衰减系数的关系,并在此基础上分析影响水体透明度的主要因子.研究结果表明：（1）上海市公园绿地景观水体透明度普遍较低,平均透明度为（0.54±0.24） m,98.31%的水体透明度低于1 m;（2）透明度与光学衰减系数显著负相关,两者之间可建立数学关系式为Kd=0.017+〖SX(〗1.12〖〗ST〖SX)〗;（3）悬浮物是上海城市公园绿地水体透明度的主导影响因子,总磷和铵态氮通过控制浮游藻类的营养水平来影响水体透明度.研究结果为科学合理地评价景观水体水质尤其是水体透明度提供测度,并为水体环境的改善、水生植被的构建及水体的养护管理提供科学依据.     

水体结冰期营养盐和叶绿素a的分布特征

以长春市某公园景观水体为研究对象, 对其在冰封过程中营养盐在冰层和水体中的存在形态、 叶绿素a等的时空分布特征, 以及营养盐与叶绿素a之间的关系进行研究. 结果表明, 冰封条件下, 冰层中营养盐的含量约为水体中的1/3, 叶绿素a约为水体中的1/5. 水体中的氮主要以无机氮的形态存在, 且 ρ_NH+4>ρ_NO-3>ρ_NO-2; 磷以溶解性总磷为主; 叶绿素a在冰封过程中缓慢增长. 底层水体中,ρ_NH+4, _TP高于上层水体.     

地拉韦啶的合成及晶体结构

以烟酰胺、 对硝基苯肼和丙酮酸乙酯等为原料合成目标化合物地拉韦啶(C₂₃H₃₂N₆O₄S), 并用核磁共振氢谱(¹H NMR)和核磁共振碳谱(¹³C NMR)表征其结构, 通过X射线单晶衍射确定其晶体结构. 实验结果表明: 该晶体属于正交晶系, P2₁2₁2₁空间群; 晶体学数据为： a=1.096 9(4)nm, b=1.152 5(4)nm, c=1.951 0(7)nm, α=90°, β= 90°, γ=90°, V=2.468 5(15)nm³, Mr=488.61, Z=4, Dc=1.315 g/cm³, λ=0.071 073 nm, μ=0.172 mm^-1, F(000)=1 040, R=0.040 7, wR=0.090 5; 共收集14 875个衍射点, 其中4 851个为独立衍射点(Rint=0.040 7), 在I>2σ(I)时可观察到4 099个衍射点.     

利用BP神经网络预测大伙房水库叶绿素a质量浓度

利用HJ-1卫星CCD数据,通过MATLAB软件计算,分析了多光谱CCD数据的4个波段(近红外波段、红色波段、绿色波段、蓝色波段)参与的65个波段组合与叶绿素a质量浓度之间的关系.研究发现波段组合T1=B4/B3与叶绿素a质量浓度相关性最高,并以此为自变量建立一维线性模型.利用BP神经网络进行模型建立与预测,对比两者的拟合度R2和均方根误差RMSE以及验证点的相对误差.结果表明,利用BP神经网络预测的大伙房水库叶绿素a质量浓度与实测值较为接近,并且效果优于线性模型.     

澳洲茄胺盐酸盐的质量控制

研究以高效液相色谱法控制澳洲茄胺盐酸盐质量的方法. 色谱柱为Agilent ZORBAXEclipse XDB-C₁₈柱(150 mm×4.6 mm, 5 μm), 流动相为V_{甲醇∶V乙腈∶V0.020 mol·L^-1乙酸铵=60 ∶35 ∶5, 流速为1 mL/min, 检测波长为205 nm, 进样量为10 μL. 结果表明, 采用该方法 澳洲茄胺盐酸盐与其他杂质分离良好, 线性 范围5~500 μg/mL(r=0.999 3, 理论塔板数n＞12 000, R＞1.5), 加 样平均回收率为98.6%(n=9), 重现性试验相对标准偏差（RSD）为0.618%.}     

素环导子的一个恒等式

利用环的广义多项式恒等式理论研究满足一定微分恒等式的环. 证明了： 设R是特征不为2的素环, L是R的非中心Lie理想, d是R上的导子,
如果对任意的u,v,w∈L, 有u^l(d(v) ° v)^mwⁿ=0, 其中l,m,n是固定的正整数, 则d=0.     

Characterization of Ordovician carbonate reservoirs, southeastern Saskatchewan, Canada

The discovery of the prolific Ordovician Red River reservoirs in 1995 in southeastern Saskatchewan was the catalyst for extensive exploration activity which resulted in the discovery of more than 15 new Red River pools. The best yields of Red River production to date have been from dolomite reservoirs. Understanding the processes of dolomitization is, therefore, crucial for the prediction of the connectivity, spatial distribution and heterogeneity of dolomite reservoirs.The Red River reservoirs in the Midale area consist of 3～4 thin dolomitized zones, with a total thickness of about 20 m, which occur at the top of the Yeoman Formation. Two types of replacement dolomite were recognized in the Red River reservoir: dolomitized burrow infills and dolomitized host matrix. The spatial distribution of dolomite suggests that burrowing organisms played an important role in facilitating the fluid flow in the backfilled sediments. This resulted in penecontemporaneous dolomitization of burrow infills by normal seawater. The dolomite in the host matrix is interpreted as having occurred at shallow burial by evaporitic seawater during precipitation of Lake Almar anhydrite that immediately overlies the Yeoman Formation. However, the low δ18O values of dolomited burrow infills (-5.9‰～ -7.8‰, PDB) and matrix dolomites (-6.6‰～ -8.1‰, avg. -7.4‰ PDB) compared to the estimated values for the late Ordovician marine dolomite could be attributed to modification and alteration of dolomite at higher temperatures during deeper burial, which could also be responsible for its 87Sr/86Sr ratios (0.7084～0.7088) that are higher than suggested for the late Ordovician seawaters (0.7078～0.7080). The trace amounts of saddle dolomite cement in the Red River carbonates are probably related to "cannibalization" of earlier replacement dolomite during the chemical compaction.     

A computer generator for randomly layered structures

AcomputergeneratorforrandomlylayeredstructuresYUJia shun1,2,HEZhen hua2(1.TheInstituteofGeologicalandNuclearSciences,NewZealand;2.StateKeyLaboratoryofOilandGasReservoirGeologyandExploitation,ChengduUniversityofTechnology,China)Abstract:Analgorithmisintrod…     

海南岛地体及其毗邻陆缘晚中生代—新生代古地磁研究和构造演化

本文叙述了对海南岛及其毗邻大陆边缘白垩纪到第四纪地层岩石进行古地磁研究的全部工作过程。通过分析岩石中剩余磁矢量的磁偏角及磁倾角的变化,提出海南岛白垩纪以来经历的构造演化模式如下:早期伴随顺时针旋转而向南迁移,后期伴随逆时针转动并向北运移。联系该地区及邻区的地质、地球物理资料,对海南岛上述的构造地体运动提出以下认识:北部湾内早期有一拉张作用,主要是该作用使湾内地壳显著伸长减薄,形成北部湾盆地。从而导致了海南岛的早期构造运动,而海南岛后期的构造运动则主要是受南海海底扩张的影响。海南地体运动规律的阐明对于了解北部湾油气盆地的形成演化有重要的理论和实际意义。     

Exciton Seebeck in Molecular Systems

Various applications relevant to the exciton dynamics,such as the organic solar cell,the large-area organic light-emitting diodes and the thermoelectricity,are operating under temperature gradient.The potential abnormal behavior of the exicton dynamics driven by the temperature difference may affect the efficiency and performance of the corresponding devices.In the above situations,the exciton dynamics under temperature difference is mixed with     

Achieving Unusual States of Matter Under High Pressure

The elongation method,originally proposed by Imamura was further developed for many years in our group.As a method towards O(N)with high efficiency and high accuracy for any dimensional systems.This treatment designed for one-dimensional(ID)polymers is now available for three-dimensional(3D)systems,but geometry optimization is now possible only for 1D-systems.As an approach toward post-Hartree-Fock,it was also extended to     

《Chinese Science Bulletin》SUBJECT INDEX TO VOLUME 59(2014)

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An on-line scaling method for improving scalability of a database cluster

The explosive growth of the Internet and database applications has driven database to be more scalable and available, and able to support on-line scaling without interrupting service. To support more client's queries without downtime and degrading the response time, more nodes have to be scaled up while the database is running. This paper presents the overview of scalable and available database that satisfies the above characteristics. And we propose a novel on-line scaling method. Our method improves the existing on-line scaling method for fast response time and higher throughputs. Our proposed method reduces unnecessary network use, i.e. , we decrease the number of data copy by reusing the backup data. Also, our on-line scaling operation can be processed parallel by selecting adequate nodes as new node. Our performance study shows that our method results in significant reduction in data copy time.     

An improved R-tree based on childnode''s probability

R-Tree is a good structure for spatial searching. But in this indexing structure,either the sequence of nodes in the same level or sequence of traveling these nodes when queries are made is random. Since the possibility that the object appears in different MBR which have the same parents node is different, if we make the subnode who has the most possibility be traveled first, the time cost will be decreased in most of the cases. In some case, the possibility of a point belong to a rectangle will shows direct proportion with the size of the rectangle. But this conclusion is based on an assumption that the objects are symmetrically distributing in the area and this assumption is not always coming into existence. Now we found a more direct parameter to scale the possibility and made a little change on the structure of R-tree, to increase the possibility of founding the satisfying answer in the front sub trees. We names this structure probability based arranged R-tree (PBAR-tree).     

Integrating GIS Web services based on mediating architecture

The geographic information service is enabled by the advancements in general Web service technology and the focused efforts of the OGC in defining XML-based Web GIS service. Based on these models, this paper addresses the issue of services chaining,the process of combining or pipelining results from several interoperable GIS Web Services to create a customized solution. This paper presents a mediated chaining architecture in which a specific service takes responsibility for performing the process that describes a service chain. We designed the Spatial Information Process Language (SIPL) for dynamic modeling and describing the service chain, also a prototype of the Spatial Information Process Execution Engine (SIPEE) is implemented for executing processes written in SIPL. Discussion of measures to improve the functionality and performance of such system will be included.     

Tracking data management using topology of moving object database system for moving object constrained trajectory in LBS application

Advances in wireless technologies and positioning technologies and spread of wireless devices, an interest in LBS (Location Based Service) is arising. To provide location based service, tracking data should have been stored in moving object database management system (called MODBMS) with proper policies and managed efficiently. So the methods which acquire the location information at regular time intervals then, store and manage have been studied. In this paper, we suggest tracking data management techniques using topology that is corresponding to the moving path of moving object. In our techniques, we update the MODBMS when moving object arrived at a street intersection or a curved road which is represented as the node in topology and predict the location at past and future with attribute of topology and linear function. In this technique, location data that are corresponding to the node in topology are stored, thus reduce the number of update and amount of data. Also in case predicting the location,because topology are used as well as existing location information, accuracy for prediction is increased than applying linear function or spline function.