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1.
气相色谱法(NPD)测定水和土壤中精喹禾灵的残留量   总被引:1,自引:0,他引:1  
建立了气相色谱法氮磷检测器(GC-NPD)测定水和土壤中的精喹禾灵残留的分析方法,方法的线性范围为0.04~1mg/kg,线性相关系数为0.9994,最低检出限为0.008mg/kg.在水样和土壤中进行添加回收试验,添加浓度在0.04~4mg/kg间,测得其回收率分别在88.7~105.9%和80.2~109.5%之间,变异系数分别为2.18~3.10%和2.06~3.32%.  相似文献   

2.
在(27±1)℃、相对湿度75%~80%、光周期12L:12D条件下研究了井上蛀果斑螟(Assara inouei)成虫的羽化、交配行为.结果表明:羽化全天可见,92%于暗期羽化.羽化高峰期在21:00~22:00之间,雄虫羽化率为22.12%,雌虫的为12.91%.成虫交配主要集中在羽化后的1~4 d,在羽化后的第2天交配率达到最大值.交配时间发生在1:00~9:00之间,5:00~6:00之间交配率最大为37.14%.  相似文献   

3.
压力曝气生物反应器处理废水的研究   总被引:1,自引:0,他引:1  
压力曝气反应器采用压力曝气提高混合液的溶解氧及有机物降解速度,曝气压力为0.05~0.25 MPa;密闭塔式结构,设备最佳高度与直径比为3∶1.以乙醛废水为试验介质,在曝气压力分别为0.10,0.15,0.20 MPa时,反应器中混合液溶解氧(DO)质量浓度达到5.0,7.5,10.0 mg.L-1;有机物降解速度(以化学耗氧量COD计)分别为5.80,7.20和9.50 kg.m-3.d-1,为常压曝气的2.5~4.0倍.在曝气压力为0.15~0.20 MPa时,污泥表观产率为常压曝气的1/2~1/3左右,混合液微生物脱氢酶活性指示物(TF)质量浓度达到80μg.mL-1.应用该反应器处理味精废水,污泥龄为5~8 d,污泥质量浓度为3 500~5 000 mg.L-1,水力停留时间为7 h,曝气压力0.10 MPa,曝气量为处理水量的20~30倍,COD去除率达到97.7%,NH3-N去除率达到96.0%,处理出水达到国家一级排放标准.  相似文献   

4.
建立HPLC法同时测定舒肝健胃丸中五种成分(芍药苷、柚皮苷、橙皮苷、和厚朴酚与厚朴酚)含量的方法.采用高效液相色谱法,色谱柱为TC-C18(4.6 mm×250 mm,5μm),检测波长为0~10 min,230 nm,10~20 min,283 nm和20~55 min,294 nm;流动相为乙腈-水溶液,梯度洗脱0~15 min,22%~22%;15~25 min,22%~72%;25~35 min,72%~72%;35~40 min,72%~90%;40~50 min,90%~90%;50~55 min,90%~22%;流速为1.0 m L·min-1;柱温为25℃.芍药苷、柚皮苷、橙皮苷、和厚朴酚与厚朴酚的质量浓度分别在0.672~67.2 mg·mL~(-1)、3.124~312.4 mg·mL~(-1)、2.3712~237.12 mg·mL~(-1)、0.44~440 mg·mL~(-1)和1.196-1~119.6 mg·mL~(-1)范围内呈良好的线性关系.测定舒肝健胃丸中芍药苷、柚皮苷、橙皮苷、和厚朴酚和厚朴酚的含量分别为0.68 mg·g~(-1)、2.85 mg·g~(-1)、6.75 mg·g~(-1)、1.09 mg·g~(-1)和1.09 mg·g~(-1).本方法简单方便、准确可靠、专属性强,为舒肝健胃丸药品的质量控制提供了方法依据.  相似文献   

5.
间硝基偶氮氯膦在酸性溶液中与稀土离子形成蓝或绿色的络合物。当草酸存在下,可掩蔽钇组稀土而测定铈组稀土。本文试验了测定条件并试用于测定铁基、镍基合金中微量铈组稀土元素。在实验条件下,在与试样相应的铁、镍、镍铬含量存在下,铈的摩尔吸光系数依次为8. 7×10~4、8. 6×10~4及9. 3×10~4升·摩尔~(-1) ·厘米~(-1) ;Sandell 灵敏度依次为0. 0016、 0. 0016及0. 0015微克、铈(Ⅲ)/厘米~2;比耳定律范围依次为0~12、 0~10及0~10微克铈(Ⅲ)/25毫升,五倍钇存在时不干扰。对铁基合金中含铈量为0. 025%、镍硅合金中含铈量为0. 022%、镍铬合金中含铈量为0. 021%分别作10次平行测定时,其标准偏差依次为0. 0036、 0. 0017及0. 0011;变异系数依次为1. 7%、0. 74%及0. 46%。铈的回收率为96~105%。用本法测定铁基、镍基合金中微量铈组稀土元素,可获得满意结果。  相似文献   

6.
利用HotDisk热常数分析仪对THF水合物导热系数和热扩散系数进行了非原位测量。实验结果表明,温度在254.0~267.0 K时非原位测得的THF水合物导热系数为0.52~0.57 W.m-1.K-1,且随着温度的增加而线性增大,非原位测量的导热系数值与原位测量的导热系数值绝对值相差0.045~0.065 W.m-1.K-1,误差为8%~12%。当温度从267.0 K升高到277.0 K时,非原位测得的THF水合物的导热系数增加剧烈,表现出非线性关系。在254.0~267.0 K时,非原位测得的THF水合物的热扩散系为0.26~0.31 mm2.s-1,并随温度增加而减小。非原位测量的热扩散系数值与原位测量的热扩散系数绝对值相差0.028~0.068 mm2.s-1,误差为10%~22%。原位测量与非原位测量产生的误差,分析认为可能是样品的转移过程中,空气中的水蒸气在水合物表面凝结成冰所致。  相似文献   

7.
采用反相高效液相色谱法(RP-HPLC)同时测定了三七安宫胶囊中三七皂苷和人参皂苷的含量.实验中,用十八烷基硅烷键合硅胶作为填充剂,乙腈-0.2%磷酸梯度洗脱(0~30 min,V乙腈∶V磷酸=20∶80;31~80 min,V乙腈∶V磷酸=30∶70)作流动相,检测波长为203nm,流速为1.0 mL/min.结果表明:三七皂苷R1在0.42~2.10μg范围内线性关系良好(r=0.999 6),平均回收率(n=5)为96.4%;人参皂苷Rg1在1.59~10.6μg范围内线性关系良好(r=0.999 9),平均回收率(n=5)为97.7%;人参皂苷Rb1在1.497~9.98μg范围内线性关系良好(r=0.999 7),平均回收率(n=5)为98.1%.  相似文献   

8.
利用厌氧反应器(UASB)与固定生物膜-活性污泥(IFAS)反应器探究厌氧消化、同时亚硝化-厌氧氨氧化-反硝化(SNAD)工艺对垃圾渗滤液的处理效果.控制UASB的温度为32℃,pH 为8.0~8.3,在水力停留时间(HRT)为24h时COD去除率为44.9%,出水碳氮比在1.3∶1左右,完全可以满足后续SNAD工艺需求.两级串联SNAD-IFAS反应器共运行96d,UASB 出水稀释后作为SNAD 工艺的进水.独立调控两池的温度、DO 浓度、pH,SNAD1池分别为32 ℃、0.1~0.2mg·L-1、7.8~8.0,SNAD2池分别为32 ℃、0.08~0.14mg·L-1、7.5~7.8.在进水TN和COD浓度分别为602.3mg·L-1和878.1mg·L-1时,SNAD工艺对TN和COD的去除率分别达到83.3%和39.4%.高通量测序结果表明反应器内具有典型的SNAD工艺微生物群落结构,亚硝化菌(AOB)主要存在于活性污泥中,厌氧氨氧化细菌(AnAOB)和反硝化菌(DNB)主要富集在生物膜上.SNAD1池与SNAD2池的生物膜均以AnAOB作为优势菌种,其丰度分别达到26.21%和30.82%.  相似文献   

9.
以福建省不同地区的8条高等级公路路基填土为例(低液限细粒土与低液限粗粒土),采用不同的压实机械组合,按照路基不同层位的压实标准对其进行碾压试验.结果表明:当路基填土松铺厚度为30 cm、碾压机械吨位为20~22 t、机械行驶速度在2~4 km·h~(-1)时,压实度达到93%、94%、96%所需强振碾压遍数分别为2~3、3~4、4~5遍.对黏土质砾路基,松铺厚度为40 cm、碾压机械吨位为22 t,压实度达到93%、94%、96%所需强振碾压遍数分别为1、2、4遍.对低液限粉土路基,碾压机械吨位为30 t,松铺厚度为35 cm,压实度达到93%所需强振碾压遍数为2遍;松铺厚度为45 cm,压实度达到94%、96%所需强振碾压遍数分别为4、5遍.  相似文献   

10.
使用双引发剂合成新型无卤阻燃剂二乙基次膦酸铝(Al Pi).当反应温度为80℃、反应时间为2 h、硫酸铝溶液浓度为0.1 mol/L、pH位于2.0~2.5时,产率为94.4%.产品结构通过FT-IR、ICP、~1H NMR、~(31)P NMR等分析手段表征,热重分析(TG)结果(T_(1%)=391.88℃,T_(5%)=429.38℃)表明产物热稳定性良好.当Al Pi在尼龙66(PA66)中添加量为15%时,垂直燃烧测试(UL-94)达V-0级,极限氧指数(LOI)达33.2%,阻燃性能明显提高,且冲击强度、弯曲强度等力学性能指数仍保持在材料可使用范围内.  相似文献   

11.
There are numerous geometric objects stored in the spatial databases. An importance function in a spatial database is that users can browse the geometric objects as a map efficiently. Thus the spatial database should display the geometric objects users concern about swiftly onto the display window. This process includes two operations:retrieve data from database and then draw them onto screen. Accordingly, to improve the efficiency, we should try to reduce time of both retrieving object and displaying them. The former can be achieved with the aid of spatial index such as R-tree, the latter require to simplify the objects. Simplification means that objects are shown with sufficient but not with unnecessary detail which depend on the scale of browse. So the major problem is how to retrieve data at different detail level efficiently. This paper introduces the implementation of a multi-scale index in the spatial database SISP (Spatial Information Shared Platform) which is generalized from R-tree. The difference between the generalization and the R-tree lies on two facets: One is that every node and geometric object in the generalization is assigned with a importance value which denote the importance of them, and every vertex in the objects are assigned with a importance value,too. The importance value can be use to decide which data should be retrieve from disk in a query. The other difference is that geometric objects in the generalization are divided into one or more sub-blocks, and vertexes are total ordered by their importance value. With the help of the generalized R-tree, one can easily retrieve data at different detail levels.Some experiments are performed on real-life data to evaluate the performance of solutions that separately use normal spatial index and multi-scale spatial index. The results show that the solution using multi-scale index in SISP is satisfying.  相似文献   

12.
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   

13.
AcomputergeneratorforrandomlylayeredstructuresYUJia shun1,2,HEZhen hua2(1.TheInstituteofGeologicalandNuclearSciences,NewZealand;2.StateKeyLaboratoryofOilandGasReservoirGeologyandExploitation,ChengduUniversityofTechnology,China)Abstract:Analgorithmisintrod…  相似文献   

14.
Instead of following Fock’s expansion,we solve the Schrodinger equation for some quantum mechanical manybody systems such as electrons in atoms and charged excitons in quantum wells in a similar way in hyperspherical coordinates by expanding the wave functions into orthonormal complete basis sets of the hyperspherical hannonics(HHs)of hyperangles and generalized Laguerre polynomials(GLPs)of the hyperradius.This leads the equation to  相似文献   

15.
Future mobile communication systems aim at providing very high data transmission rates, even in high-mobility scenarios such as high-speed wheel-track trains, maglev trains, highway vehicles, airplanes, guided missiles or spacecraft. A particularly important commercial application is the strong and increasing worldwide demand for high- speed broadband wireless communications (up to 574.8 km/ h test speeds or 380 km/h commercial speeds) in railways, providing data, voice and video services for applications such as onboard entertainment services to passengers, train control, train dispatch, train sensor status handling and sur- veillance. In such high-mobility scenarios, there are a number of communication challenges, including fast hand- over, location updating, high-speed channel modeling, estimation and equalization, anti-Doppler spreading tech- niques, fast power control, and dedicated network architec- ture. Because signal transmission in very high-speed scenarios will inevitably experience serious deterioration, it is imperative to develop key broadband mobile communi- cation techniques for such high-speed vehicles.  相似文献   

16.
17.
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   

18.
Being the primary media of geographical information and the elementary objects manipulated, almost all of maps adopt the layer-based model to represent geographic information in the existent GIS. However, it is difficult to extend the map represented in layer-based model. Furthermore, in Web-Based GIS, It is slow to transmit the spatial data for map viewing. In this paper, for solving the questions above, we have proposed a new method for representing the spatial data. That is scale-based model. In this model we represent maps in three levels: scale-view, block, and spatial object, and organize the maps in a set of map layers, named Scale-View, which associates some given scales.Lastly, a prototype Web-Based GIS using the proposed spatial data representation is described briefly.  相似文献   

19.
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   

20.
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   

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