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1.
针对目前光纤环形腔衰荡光谱技术多用于测量单一通道或者单一物理量的问题,依据双通道同步检测的思想,在传感系统中结合延迟线方法,搭建了基于光纤环形腔衰荡光谱技术的双路复用微位移传感系统,并对其重复性、灵敏度、复用性等特性进行了实验研究。结果表明:该系统可在双通道条件下分别实现0~10位移测量,且在未发生位移时两路传感器的重复性测试结果分别为(0.950 080 6±0.001 151)μs~(-1)和(0.953 523±0.001 757)μs~(-1);当两路传感分别产生6 mm和5 mm的位移时,重复性测试参数变化为(0.955 884±0.001 966 4)μs~(-1)和(0.959 957±0.002 013)μs~(-1);双路传感器的灵敏度分别为(1.07×10~(-3)±7.337×10~(-5))μs~(-1)·mm~(-1)和(1.00×10~(-3)±4.130×10~(-5))μs~(-1)·mm~(-1).经实验验证,双路传感器的相对误差分别为2.1%,4.0%,可为实现多参数同步检测提供一种有效的途径和方法。  相似文献   

2.
目的:建立复方肝舒丸的质量标准.方法:采用薄层色谱法对丸剂中的丹参、大黄、当归、白术进行定性鉴别.采用高效液相色谱(HPLC)法测定丸剂所含丹参酮ⅡA的量,色谱柱为Welchrom-C18柱(5μm,250 mm×4.6mm),流动相为甲醇-水(体积比80∶20),流速1.0 m L·min-1,柱温30℃,检测波长为270 nm.采用HPLC法测定大黄素、大黄酚的含量,色谱柱为Welchrom-C18柱(5μm,250 mm×4.6 mm),流动相为甲醇-0.1%磷酸溶液(体积比90∶10),柱温25℃,流速1.0 m L·min-1,检测波长为254 nm.结果:薄层斑点清晰,阴性对照无干扰,专属性强.丹参酮ⅡA在0.02~0.2μg范围内线性关系良好(r=0.9999),平均加样回收率为99.26%,RSD为0.66%(n=9).大黄酚在0.2~2.0μg范围内线性关系良好(r=0.9999),平均加样回收率为99.21%、RSD为0.72%(n=9).大黄素在0.2~2.0μg范围内线性关系良好(r=0.9999),平均加样回收率为99.21%,RSD分别0.61%(n=9).结论:本方法操作简单、灵敏度高、结果准确、重现性好、专属性强,可作为复方肝舒丸的质量控制标准.  相似文献   

3.
疏浚淤泥固化土宏微观孔隙结构特征及其对渗透性影响   总被引:1,自引:0,他引:1  
采用压汞试验、渗透率试验和孔隙度试验等方法,研究疏浚淤泥固化土(DSSS)的孔隙度、微观孔隙结构特征、渗流特征及其相互关系.压汞试验结果显示,DSSS的孔隙体积频率分布曲线均为典型的双峰曲线,存在两个集中的孔喉半径区间:0.02~0.04μm和3~30μm.基于DSSS水化反应生成的致密水化产物和孔隙体积频率分布曲线,将DSSS的孔隙直径进行分组,微孔组和中孔组处于峰值区间,微孔组的最可几孔径随着初始密度和养护龄期的增加逐渐增大,中孔组的最可几孔径随着初始密度和养护龄期的增加逐渐减小.另外,孔隙度和渗透率试验结果显示,DSSS有效孔隙度随养护龄期逐渐减小主要发生在固化28d前,28d后DSSS有效孔隙度基本保持不变,而DSSS渗透系数仍在降低,在该阶段50%以上的中孔向小孔和微孔转化.因此,提出采用有效孔隙度作为表征DSSS的宏观孔隙特征参数,采用孔径和体积频率值作为表征微观孔隙特征参数,并采用毛细模型建立宏微观孔隙结构参数和渗透性之间的定量关系.  相似文献   

4.
为探究Q3马兰黄土孔隙分形特征与渗透性之间的联系及为其孔隙结构量化提供参考,通过压汞试验,基于各种分形模型计算不同尺度范围孔隙分形维数,将结果与实测渗透系数及理论渗透系数进行相关分析,筛选最适模型,为渗透性评价提供参考.结果表明:①质量分形维数在尺度范围430~2μm、32~0.2μm、430~0.2μm内均与渗透系数呈正相关,相关性0.79以上,体积分形维数仅在430~0.2μm内与渗透系数呈负相关,相关性0.70以上;②通过两者分形维数计算的迂曲度分形维数均与渗透系数呈负相关,相关性0.79以上,排驱压力、微孔含量与质量分形维数呈负相关、与中值孔径正相关,这与体积分形维数恰好相反.可见基于孔隙率的质量分形维数与基于孔径搭配的体积分形维数对评价马兰黄土渗透性有重要参考意义.  相似文献   

5.
鄂尔多斯盆地下寺湾地区陆相页岩孔隙类型多样,微观非均质性强,为研究该区延长组长7陆相页岩储层孔隙特征,文中通过岩心描述、薄片观察、场发射扫描电镜等直接观察技术手段,结合气体吸附、核磁共振等实测分析技术,对陆相页岩的孔隙类型、大小分布进行研究。研究结果表明:长7页岩孔隙类型包括无机粒间孔、无机粒内孔和有机孔3大类及残余粒间孔、溶蚀粒间孔、碎屑与黏土粒间孔、溶蚀粒内孔、黏土矿物晶间微孔、有机孔、微裂缝7个亚类。页岩孔径从0.3 nm至15μm范围内均发育,孔径100 nm以下的微孔,以有机孔和黏土矿物晶间孔隙为主,占总孔孔体积的41%~73%;孔径大于5μm的孔隙,以溶蚀孔隙为主,占总孔孔体积的25%~55%,页岩中的孔体积主要是由大孔和微孔贡献最大,成因以溶蚀孔和有机孔为主。分析孔隙发育影响因素可知:长7页岩中大孔(孔径 10μm)孔隙体积与黏土矿物(25%~60%)、方解石含量(0.6%~2.7%)具有负相关关系,黏土矿物和方解石含量的增加占据粒间孔隙空间,大孔孔隙体积与斜长石、石英含量具有正相关关系,微孔(孔径100 nm)的体积与黏土矿物含量具有正相关性。有机质含量和热演化程度是控制有机孔体积的主要因素,在低热演化背景下(Tmax460℃),有机孔体积随热成熟度增大而增高。  相似文献   

6.
使用Li-6400便携式光合测定仪,对自然条件下呼伦贝尔草原羊草的光合及水分生理生态特征进行了研究,结果表明:八月的呼伦贝尔草原多阴云天气,羊草的净光合速率日变化呈现双峰曲线,蒸腾速率曲线与净光合速率表现出一致的趋势.光响应曲线、CO_2响应曲线结果表明:光合速率(P_n)与CO_2浓度(C_(CO_2))之间回归方程为P_n=-0.09051+0.03865 C_(CO_2)-1×10~(-5) C_(CO_2)~2,根据回归方程可求得CO_2补偿点为2.34μmol·m~(-2)·s~(-1),CO_2饱和点为1932.5μmol·m~(-2)·s~(-1).P_n与光合有效辐射(PAR)之间回归方程为P_n=-2.0596+0.02094 PAR-8×10~(-6) PAR2,光补偿点(LCP)为102.36μmol·m~(-2)·s~(-1),光饱和点(LSP)为1308.75μmol·m~(-2)·s~(-1),羊草较高的光补偿点和光饱和点是其适应内蒙古高原高光强环境的表现,也是其成为该地区优势植物的适应对策.  相似文献   

7.
为研究换热器的低温腐蚀,搭建了换热器烟气低温腐蚀实验台。实验台可模拟烟气环境并实现多种因素的定量控制。以工业余热回收中常用的H型翅片管为对象,进行了H型翅片管换热器烟气低温腐蚀影响因素的实验研究。观察并分析了H型翅片管在不同壁面温度下的表面形貌变化以及腐蚀产物,得到了不同烟气流量、烟气温度、烟气酸体积分数以及壁面温度对应的酸沉积速率。结果表明:壁面温度低于水蒸气露点时腐蚀较为严重,腐蚀机理为吸氧腐蚀;烟气流量、烟气温度、烟气酸体积分数以及壁面温度对酸沉积速率均有不同程度的影响;随着烟气酸体积分数从10×10~(-6)增加到50×10~(-6),酸沉积速率从2.50×10~(-7) mol·m~(-2)·s~(-1)近似线性增加到7.03×10~(-7) mol·m~(-2)·s~(-1);随着壁面温度从80℃降低到50℃,酸沉积速率从3.06×10~(-7) mol·m~(-2)·s~(-1)增大到1.75×10~(-6) mol·m~(-2)·s~(-1),当壁面温度继续降低时,沉积的酸一部分被冷凝水带走,导致测得的酸沉积速率减小;酸雾的生成和黏附对酸沉积速率有较大的影响。研究结果对开发抗低温腐蚀技术、改善烟气余热利用系统提供了实验基础。  相似文献   

8.
基于环境变迁影响的古砖孔结构及饱和系数   总被引:3,自引:0,他引:3  
通过不同水平下的淡水冻融、盐水冻融,人工模拟山西某地区环境变迁特征,采用蒸煮法和压汞法实验,建立古砖不同孔径孔隙体积和饱和系数的对应关系,评估分析环境变迁对古砖孔结构及饱和系数的影响.针对同一区域的某古建筑群不同年代的实体砖进行实验验证.研究结果表明,环境变迁导致古砖的孔隙率和孔径分布变化;其中,淡水冻融导致砖孔隙率呈现规律性变化,孔隙率缓慢增长;盐水冻融导致砖孔隙率呈现间歇性变化;小于1μm孔径孔隙体积占总孔隙体积百分数逐渐减少,1~5μm孔径孔隙体积占总孔隙体积百分数逐渐增大;孔径孔隙体积变化性能和饱和系数具有很好的相关性,有利于解决文物建筑实验样品数量不足的问题,用其替代饱和系数评定古建筑砖抗风化性能具有可行性.  相似文献   

9.
利用Andes(30.3°S,70.7°W)流星雷达2010年1月1日~2014年3月21日的观测数据,研究了中间层和低热层(mesosphere and lower thermosphere,MLT)区域水平背景风场、周日潮汐以及周日潮汐与行星波之间的相互作用;并与模式结果进行了比较。多年观测结果表明,在80~100 km高度,月平均经向风场在5~8月份是南向风,在10~2月份是北向风,其变化范围在~(-1)1~13 m·s~(-1)间,明显比HWM-07模式计算的月平均值-4~6 m·s~(-1)范围大;观测的月平均纬向风场全年主要以东向风为主,只有少数月份的少数高度为西向风,风速范围为~(-1)4~32 m·s~(-1),比模式计算的月平均值-20~37 m·s~(-1)变化范围略小。观测和GSWM-00模式给出的周日潮汐月平均振幅时空分布都呈现双峰结构,观测的最大峰值出现在3月份,经向和纬向分量月平均振幅峰值分别为51 m·s~(-1)和44 m·s~(-1),次峰出现在9月份,经向和纬向分量月平均振幅次峰值分别为40~37 m·s~(-1)。模式计算的经向和纬向月平均振幅峰值约为观测值的2倍,且峰值出现的时间也比观测值晚1~2个月。这些研究结果表明,模式对南半球月平均风场和周日潮汐的描述,与实际观测值间存在明显差异,还需要加强对南半球的观测研究,来不断提高和完善目前的模式。此外,我们的研究显示,在MLT区域,由于周日潮汐和行星波都比较强,周日潮汐能与不同周期的行星波相互作用,产生新的谱成分,从而导致潮汐发生短期变化。  相似文献   

10.
膨胀土普遍发育有微孔隙与微裂隙形成特殊的微结构,在不同环境条件下脱湿,其内部微观结构会发生剧烈变化。采用扫描电镜法和压汞法相结合的方法,对相同初始状态重塑膨胀土样在不同环境下脱湿前后内部孔隙变化进行研究,探讨不同环境条件对膨胀土微观结构变化规律,主要得出以下结论:1膨胀土样脱湿干燥时孔隙收缩,土中的大孔隙变为小孔隙,导致小孔隙和超微孔隙增多,土样中的总孔隙体积减小;2烘箱环境下高温脱湿时土体表面和内部会出现微裂隙,不同孔隙孔径分布曲线为三峰曲线;冻干法干燥过程中不会导致土体中的孔隙收缩,基本不改变土样内部结构;风干法脱湿时不同孔隙孔径分布曲线为三峰曲线,但峰值明显低于高温脱湿;恒温恒湿条件下脱湿时主要表现为小孔隙,孔径大于1μm的孔隙体积极小;3膨胀土在不同脱湿环境下脱湿后总孔隙累积体积大致是随温度升高而增加,其中孔径小于1μm孔隙体积占总孔隙的比例随温度升高而减少,而孔径大于1μm孔隙占总孔隙的比例随温度升高而增加;4电镜实验表明重塑膨胀土的孔隙主要是黏土集聚体之间的孔隙和黏土集聚体内部片状矿物的叠聚而形成的微小孔隙,表面特征复杂,孔隙之间的连通情况不好,脱湿前结构单元体呈片状且连接紧密、片状表面平直,脱湿后颗粒边缘更加清晰可见、片状呈卷曲状,且片状连接有脱离的迹象。  相似文献   

11.
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.  相似文献   

12.
AcomputergeneratorforrandomlylayeredstructuresYUJia shun1,2,HEZhen hua2(1.TheInstituteofGeologicalandNuclearSciences,NewZealand;2.StateKeyLaboratoryofOilandGasReservoirGeologyandExploitation,ChengduUniversityofTechnology,China)Abstract:Analgorithmisintrod…  相似文献   

13.
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。  相似文献   

14.
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  相似文献   

15.
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  相似文献   

16.
17.
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.  相似文献   

18.
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).  相似文献   

19.
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.  相似文献   

20.
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.  相似文献   

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