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101.
目的:探讨紫外分光光度法测定秋水仙碱中毒血清,为临床秋水仙碱中毒提供诊疗依据。方法取0.5 mL 血清加提取液(三氯甲烷∶甲醇=95∶5)4.0 mL。充分震荡萃取,高速离心,取有机层于另一试管中氮气吹干,取0.2 mL 甲醇溶解残渣,混匀,取50 mL 做紫外扫描。结果血清中秋水仙碱最大吸收峰(351±1)nm,浓度在5.0~40μg/mL 范围内呈线性,回归方程Y =0.0502X +0.0013,其相关系数为0.9995,回收率为83.8%~102.8%,相对标准差为3.3%~4.8%。日内、日间相对标准差分别为3.22%~4.74%和3.45%~4.66%,最低检出浓度为1.0μg/mL。结论该方法操作简便,分析快速,结果准确,为临床诊断秋水仙碱中毒提供了一个简便准确的检测方法。 相似文献
102.
采用一步溶剂热法制备了活化半焦负载还原氧化石墨烯掺杂二氧化钛新型负载型光催化剂,即rGO-TiO2/ASC。分别考察了高温水汽活化方法和还原氧化石墨烯rGO掺杂量对光催化脱硝性能的影响,并进一步探究光照条件、烟气氧含量和烟气湿度对NO氧化脱除的作用,得出新型负载型光催化剂rGO-TiO2/ASC光催化脱硝过程主要过程。结果表明,5%水汽高温活化半焦ASC的脱硝效率最高,反应4h后可达52%。rGO负载量为8%时,负载型光催化剂rGOTiO2/ASC脱硝性能4h后转化率达70.68%。有无O2对脱硝率影响较大,有无光照对其影响次之。无H2O时,脱硝率呈现先平稳后下降的趋势。新型负载型光催化剂rGO-TiO2/ASC的脱硝过程由光催化活性组分rGO-TiO2/ASC的光催化氧化和载体部分ASC的常规氧化两部分组成。 相似文献
103.
夏季南海浮游植物光合固碳对不同波长阳光紫外辐射的响应 总被引:2,自引:1,他引:1
阳光紫外(UV)辐射影响浮游植物光合固碳,且不同波长UV辐射的生理效应不一.本文以夏季南海近岸海域浮游植物为研究对象,采用生物加权函数(Biological weighting function,BWF,亦被称为UV辐射作用光谱)的研究方法,探讨了不同波长UV辐射对浮游植物群落光合固碳的作用.结果表明,在只有可见光情况... 相似文献
104.
Klaus Wilhelm Ingolf E. Dammasch Donald M. Hassler 《Astrophysics and Space Science》2002,282(1):189-207
The plasma conditions in the solar atmosphere and, in particular, in coronal holes are summarized, before space-borne instrumentation
for observing these regions in vacuum-ultraviolet light is briefly introduced with the Solar Ultraviolet Measurements of Emitted
Radiation (SUMER) spectrometer on the Solar and Heliospheric Observatory (SOHO) as example. Spectroscopic measurements of
small plasma jets are then analyzed in detail. Magnetic reconnection is thought to be responsible for heating the corona of
the Sun as well as accelerating the solar wind by converting magnetic energy into thermal and kinetic energies. The continuous
outflow of the fast solar wind from coronal holes on ‘open’ field lines, which reach out into interplanetary space, then requires
many reconnection events of very small scale sizes – most of them probably below the resolution capabilities of present-day
instruments. Our observations of such an event have been obtained with the Solar and Heliospheric Observatory (SOHO) providing
both high-resolution imaging and spectral information for structural and dynamical studies. We find whirling or rotating motions
as well as jets with acceleration along their propagation paths in close spatial and temporal vicinity to the coronal jet.
This revised version was published online in July 2006 with corrections to the Cover Date. 相似文献
105.
We investigate UV and optical spectra of a sample of nearby early-type galaxies with evidence of nuclear line emission. The
spectral signatures of various contributors to the UV, such as the interstellar medium and various stellar populations are
analyzed and compared with the optical spectral properties. We discuss the impact of these effects on the observational properties
of galaxy evolution.
This revised version was published online in August 2006 with corrections to the Cover Date. 相似文献
106.
107.
安微淮南潘北煤矿–580 m水平探4孔与ES1C3上3-1孔在疏放太原组灰岩水时带有臭鸡蛋气味,且水流过程中伴有白色絮状漂浮物。通过采集水样,测试了出水孔水质及气体,分析了其形成原因。结果表明:气体为H2S,两出水孔的水质均具有低SO2–4、高HCO–3、弱碱性特征,白色絮状物为有机质和钙、镁物质的结合,该异常现象是脱硫酸与脱碳酸共同作用的结果。为及时处理异味对井下作业环境的影响,采用纳米二氧化钛–紫外光催化氧化法在室内对水进行硫化氢去除试验,其去除率为80%~90%,效果显著。 相似文献
108.
A preliminary methods comparison for measurement of dissolved organic nitrogen in seawater 总被引:2,自引:0,他引:2
Jonathan H. Sharp Kathrine R. Rinker Karen B. Savidge Jeffrey Abell Jean Yves Benaim Deborah Bronk David J. Burdige Gustave Cauwet Wenhao Chen Marylo D. Doval Dennis Hansell Charles Hopkinson Gerhard Kattner Nancy Kaumeyer Karen J. McGlathery Jeffrey Merriam Nick Morley Klaus Nagel Hiroshi Ogawa Carol Pollard Mireille Pujo-Pay Patrick Raimbault Raymond Sambrotto Sybil Seitzinger Georgina Spyres Frank Tirendi Ted W. Walsh C. S. Wong 《Marine Chemistry》2002,78(4)
Routine determination of dissolved organic nitrogen (DON) is performed in numerous laboratories around the world using one of three families of methods: UV oxidation (UV), persulfate oxidation (PO), or high temperature combustion (HTC). Essentially all routine methods measure total dissolved nitrogen (TDN) and calculate DON by subtracting the dissolved inorganic nitrogen (DIN). While there is currently no strong suggestion that any of these methods is inadequate, there are continuing suspicions of slight inaccuracy by UV methods.This is a report of a broad community methods comparison where 29 sets (7 UV, 13 PO, and 9 HTC) of TDN analyses were performed on five samples with varying TDN and DIN concentrations. Analyses were done in a “blind” procedure with results sent to the first author. With editing out one set of extreme outliers (representing 5 out of 145 ampoules analyzed), the community comparability for analyzing the TDN samples was in the 8–28% range (coefficient of variation representing one standard deviation for the five individual samples by 28 analyses). When DIN concentrations were subtracted uniformly (single DIN value for each sample), the comparability was obviously worse (19–46% cv). This comparison represents a larger and more diverse set of analyses, but the overall comparability is only marginally better than that of the Seattle workshop of a decade ago. Grouping methods, little difference was seen other than inconclusive evidence that the UV methods gave TDN values for several of the samples higher than HTC methods. Since there was much scatter for each of the groups of methods and for all analyses when grouped, it is thought that more uniformity in procedures is probably needed. An important unplanned observation is that variability in DIN analyses (used in determining the final analyte in most UV and PO methods) is essentially as large as the variability in the TDN analyses.This exercise should not be viewed as a qualification exercise for the analysts, but should instead be considered a broad preliminary test of the comparison of the families of methods being used in various laboratories around the world. Based on many independent analyses here, none of the routinely used methods appears to be grossly inaccurate, thus, most routine TDN analyses being reported in the literature are apparently accurate. However, it is not reassuring that the ability of the international community to determine DON in deep oceanic waters continues to be poor. It is suggested that as an outgrowth of this paper, analysts using UV and PO methods experiment and look more carefully at the completeness of DIN conversion to the final analyte and also at the accuracy of their analysis of the final analyte. HTC methods appear to be relatively easy and convenient and have potential for routine adoption. Several of the authors of this paper are currently working together on an interlaboratory comparison on HTC methodology. 相似文献
109.
D. Manzoori 《Astronomische Nachrichten》2012,333(3):256-265
Solutions of the new standard V‐light curves for the EA type binary UV Leo are obtained using the PHOEBE code (0.31a version). Absolute parameters of the stellar components were then determined, enabling them to be positioned on the absolute magnitude‐color (l.e. MV vs. B – V) isochrones diagram, based on which the age of the system is estimated to be >4×109 yr. Also times of minima data (“O – C curve”) have been analyzed. Apart from an almost sinusoidal variation with a period of 29.63 yr, which modulates the orbital period, and was attributed to a third body orbiting around the system, other cyclic variation in the orbital period and also brightness, with time scales of 24.25 and 22.77 yr were found, respectively. We associate this with a magnetic activity cycle newly reported here for UV Leo (© 2011 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim) 相似文献
110.
本文概要论述了排水管道CIPP拉入法内衬修复技术采用紫外线固化的工艺过程、技术优势;并根据紫外线固化工艺存在的技术缺陷,提出了有针对性的可操作的质量验收方法,希望对管道业主同仁们在紫外线固化工程验收时有所助益,以进一步促进管道非开挖修复事业在我国的健康发展。 相似文献