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MAEDAT NAKAGAMAT MORITAT UCHIYAMAK HOBOT 《环境化学》2003,22(3):275-277
1 IntroductionInmodernanalyticalchemistry ,chromatographyandemissionspectroscopyandtheircombinedusearebecominganincreasinglyimportanttechniqueforthemeasurementofenvironmentalpollu tants.AtomicemissiondetectorusedinGCcanprovidehighlysensitiveandselectiveresponsewithwidedynamicrangeforvariouselementsinelutingcompounds[1—4 ].Itcanalsoprovidespectrumofelementssimultaneously ,sotheycouldbeusedforempiricalformuladetermination .Wehavedevelopedanatomicemissiondetectorusingradiofrequencydischargepla… 相似文献
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A method that can be used for the monitoring of exposure to alkylating agents in the environment is presented. It is based on the quantification of alkylated N‐terminal valines in hemoglobin, using a modified Edman degradation procedure. The detection limit (GC/electron capture detector or GC/MS) is increased by two magnitudes of ten when using pentafluorophenyl isothiocyanate instead of phenyl isothiocyanate in the derivatization step. As little as one nmole N‐(—2 hydroxyethyl)valine per gram hemoglobin can be detected under practical conditions. 相似文献
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植物体内水杨酸分析方法的探讨及其应用(Investigation and Application of Analysis Methods of Salicylic Acid in Plant Tissue) 总被引:1,自引:0,他引:1
准确测定植物中水杨酸的含量是深入研究其重要作用和抗病机理的必要前提.采用高效液相色谱(HPLC)对植物中内源水杨酸进行了分析,比较了紫外检测器和荧光检测器不同的检测结果,发现荧光监测器灵敏度更高,是紫外检测器的15倍.论文同时比较了使水杨酸与其他组分很好分离的液相色谱条件,结果表明,pH5.5的乙酸钠:甲醇(9:1,V/V)的流动相效果最好.用该方法测得的精密度的相对标准偏差为1.73%,重现性和稳定性均较好(稳定性的相对标准偏差为4.6%).论文以模式植物拟南芥(Arabidopsis thaliana)的野生型和水杨酸突变体两种类型为供试材料,对其体内水杨酸进行了提取测定,检测结果发现野生型体内的水杨酸的含量大约是水杨酸突变体的9倍,与文献报道吻合. 相似文献
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For the time being, simple and reliable methods which permit the imaging of the complex topography of contaminant plumes in groundwater are missing. The conventional methods for the punctual determination of contaminant concentrations cannot fulfill this demand. To successfully implement and utilize. Natural Attenuation, these deficits have to be overwhelmed. The detectors described in the following represent only part of the probing device system the authors have developed; it shall enable their user to image different aspects of plume topography and its time dependent change by monitoring within the undisturbed groundwater aquifer in groundwater measuring levels: ? relative freights of contaminants and trace contaminants by passive samplers [4] and ? redox milieu parameters by detectors. The detectors offer multi-purpose, tape-like probing devices of unlimited length. They are charged with a defined reserve of reactive substances. During monitoring actions, the derector tape hangs vertically stretched by a weight preferably covering from the top to the bottom of the whole water column. During the reaction period, the detector may be relaunched for repeated visual inspection. The colour changes of the detectors enable the identification of a row of parameters in the vertically (depth-) oriented profile by unbroken optical/visually perceivable imaging: ? Position of Redox potential thresholds for Mn-IV-Mn-II, Fe-III-Fe-II, Sulfate-Sulfide ? Position of ochre precipitation and iron-sulfide precipitation horizons ? Relative freights of the sum of substances effecting reduction (period until defined oxidant reserve has been reduced) ? Relative freights of the sum of substances effecting iron-sulfide oxidation (period until defined reductant reserve has been reduced) ? Position of dissolved iron-II ions containing horizons ? Position of dissolved hydrogen-sulfide ions/hydrogen-sulfide containing horizons ? Relative freights of iron-II ions (period until defined oxidant reserve has been reduced) ? Relative freights of hydrogen-sulfide ions/hydrogen-sulfide (period until defined oxidant reserve has been reduced). Furthermore, the detectors are also suitable for the examination of waters even of great depth, as for example artificial or natural lakes, sea and ocean basins. 相似文献
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A method for sampling and analysis of phenolic compounds in workplace atmospheres using Amberlite XAD‐2 sorbent tubes has been laboratory and field tested. After extraction of the adsorbed phenols with methylene chloride, the concentrated extract was analyzed by capillary column gas chromatography coupled with a flame ionization detector or a mass spectrometer. For a 3L air sample, the method has a detection limit for phenol, cresols, alkyl‐substituted phenols and xylenols of 0.3 mg/m3 using gas chromatography with flame ionization detection (GC/FID) analysis and 0.07 mg/m3 using gas chromatography mass spectroscopy/selected ion monitoring GC‐MS/SIM. Evaluation tests conducted in the laboratory indicated recoveries >85% for a wide range of phenols, cresols, xylenols and other alkyl‐substituted phenols and resorcinol. Sampling conditions were established to ensure that no breakthrough occurred for a predetermined sample volume of three (3) liters even in humid atmospheres. Stability tests indicated that for storage of up to 2 weeks at 4°C, only resorcinol showed a significant reduction in sample recovery. The proposed method and NIOSH Method 3502 were compared for the determination of phenol concentrations in air samples collected at a plant processing phenolic resins. Phenol was positively identified in the XAD sample using GC‐MS/SIM and was detected at concentrations of 40–50% of the total phenols detected using NIOSH Method 3502. This difference is attributed to the airborne paniculate matter which is known to contain bisphenols that will contribute to the total phenolic content sampled in Method 3502, but not on the XAD sample. 相似文献
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Phenolic compounds in olive oil mill wastewaters were analysed by HRGC–MS after extracting the acidified solution with ethyl acetate and derivatization with N,O-bis(trimethylsilyl)trifluoroacetamide. Both simple and complex phenols were detected with the latter being the most abundant. 1,2-dihydroxybenzene (catechol), p-hydroxyphenyl ethanol (tyrosol), 3,4-dihydroxyphenyl ethanol (hydroxytyrosol) and 4-hydroxy-3-methoxyphenyl ethanol (homovanillyl alcohol) predominated among the simple phenols using a gas chromatograph coupled with a mass selective detector. 相似文献
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People are exposed to ionizing radiation from the radionuclides that are present in different types of natural sources, of
which phosphate fertilizer is one of the most important sources. Radionuclides in phosphate fertilizer belonging to 232Th and 238U series as well as radioisotope of potassium (40K) are the major contributors of outdoor terrestrial natural radiation. The study of alpha activity in fertilizers, which
is the first ever in West Bengal, has been performed in order to determine the effect of the use of phosphate fertilizers
on human health. The data have been compared with the alpha activity of different types of chemical fertilizers. The measurement
of alpha activity in surface soil samples collected from the cultivated land was also performed. The sampling sites were randomly
selected in the cultivated land in the Midnapore district, which is the largest district in West Bengal. The phosphate fertilizer
is widely used for large agricultural production, mainly potatoes. The alpha activities have been measured using solid-state
nuclear track detectors (SSNTD), a very sensitive detector for alpha particles. The results show that alpha activity of those
fertilizer and soil samples varies from 141 Bq/kg to 2,589 Bq/kg and from 109 Bq/kg to 660 Bq/kg, respectively. These results
were used to estimate environmental radiation exposure on human health contributed by the direct application of fertilizers. 相似文献