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1.
光引发剂残留分析研究进展 总被引：4，自引：0，他引：4
光引发剂残留分析起步较晚,由于残留水平低,在分析中更多地使用了较新的高灵敏度分析技术。文章对光引发剂Benzophenone、ITX、Irgacure 184、Irgacure 907、Irgacure 369、TPO和EHA的定义、种类、来源和危害进行了介绍;总结了目前光引发剂残留分析几类检测方法,包括气相色谱-质谱联用、薄层色谱-质谱联用、液相色谱-质谱联用等,由于气相色谱使用范围的限制,液相色谱-质谱在光引发剂分析中应用越来越广泛。比较了常用的样品前处理手段的优缺点,如液-液萃取、加速溶剂萃取、固相萃取等。相对于其他方法,固相萃取更为成熟,普适性更强,便于实现大批量光引发剂中多残留分析。光引发剂的多残留分析甚至与其他农药、兽药残留同时分析是未来发展的方向。 相似文献
2.
燃煤固体产物的矿物组成研究 总被引：12，自引：1，他引：12
利用X射线衍射、穆斯堡尔谱与扫描电子显微镜等方法研究中国典型燃煤煤种的燃烧产物的矿物学特征，揭示出不同化学成分以及不同类型产物中矿物组成的差异性。根据化学成分，可将燃煤固体产物分为硅铝质、铁质和钙质三组，硅铝质产物结晶相主要为莫来石和石英，而结渣中基本为莫来石；铁质产物中主要矿物包括α-Fe2O3、γ-Fe2O3与Fe3O4，其含量随锅炉燃烧湿度的变化而变化；钙质产物中矿物种类复杂，飞灰石检出石灰、石膏和石英，沾污中检出石膏、赤铁矿和石类，而结渣中还发现钙的硅酸盐矿物。上述矿物分布特征是由不同成分的硅酸盐熔体在不同热力学条件下的结晶行为所决定的。 相似文献
3.
《International Geology Review》2012,54(1):1-14
Tar residues are common on the coastline of the Monterey Bay National Marine Sanctuary. These coastal tar residues have been washed ashore and usually occur on headlands near the high-tide line. In this study, 18 coastal tar residues were collected and analyzed to determine their carbon isotopic compositions and the values of selected biomarker ratios. All of the residues have very heavy (13C-enriched) carbon isotopic compositions spanning a narrow range (δ13C = ?22.2 to ?23.4‰), and 28,30-bisnorhopane is present in all samples. These same geochemical characteristics are found in Monterey Formation oils from which the coastal tar residues were likely derived. These coastal residues could result from natural seeps or from accidental spills. Statistically the coastal tar residues can be organized into three groups, each of which may represent different spill or seep events. Seven samples of potential local representative sources for the tar residues were examined, but none could account for the coastal tars. 相似文献
4.
S.V.S. Murty P.S. Goel D.Vu. Minh Yu.A. Shukolyukov 《Geochimica et cosmochimica acta》1983,47(6):1061-1068
Total nitrogen, measured by neutron activation analysis, is highly enriched in residues from iron meteorites obtained by dissolution of the metal in dilute H2SO4, relative to the bulk value. On the average, the residues, representing 3% mass, contain 22% of total N. Group IA has more dissolved N than IIIA. Lithium and Ir show a distribution pattern parallel to N. Total Xe has been measured in several residues and its isotopic composition is, similar to atmospheric Xe for mass numbers 131 to 136 but not for 124Xe and 126Xe which are strongly depleted in the non-magnetic residues. It is suggested that iron meteorites have trapped in their micro-inclusions, some pre-solar nebular matter which is isotopically heterogeneous. 相似文献
5.
O. O. Fatoba L. F. Petrik R. O. Akinyeye W. M. Gitari E. I. Iwuoha 《International Journal of Environmental Science and Technology》2014,11(6):1641-1652
The leaching of major species from fly ash is a function of the pH of the solution in contact with the fly ash. The aim of this study was to determine the effect of the pH of the leachant on the leaching of species from the ash residues recovered after the long-term fly ash–brine interactions. Acid neutralization capacity (ANC) tests using solutions of different pH values ranging from the initial pH of the ash residues (11–12) to pH 4 were employed in the leaching experiments. The ANC tests revealed that the release of major species from the ash residues depended on the pH of the leachants except for Na and Cl, where the significant concentrations leached were independent of the solution pH. The concentrations of Al and Si in the ANC leachates were very high at pH below 6 while Ca, K, Sr, Mg and B were immediately mobilized from the brine impacted fly ash when in contact with de-ionized water, and leaching increased as the pH decreased. The concentration of SO4 leached from the brine impacted ash residues at high pH was high, and the leaching increased with decrease in the pH of the leachant. This study shows that most of the major elements captured in the ash residues could be mobilized when in contact with aqueous solutions of various pH. This reveals that the co-disposal of fly ash and brine may not be the best practice as the major elements captured in the ash residues could leach over time. 相似文献
6.
Rock-weathering rates as functions of time 总被引：2，自引：0，他引：2
Steven M. Colman 《Quaternary Research》1981,15(3):250-264
The scarcity of documented numerical relations between rock weathering and time has led to a common assumption that rates of weathering are linear. This assumption has been strengthened by studies that have calculated long-term average rates. However, little theoretical or empirical evidence exists to support linear rates for most chemical-weathering processes, with the exception of congruent dissolution processes. The few previous studies of rock-weathering rates that contain quantitative documentation of the relation between chemical weathering and time suggest that the rates of most weathering processes decrease with time. Recent studies of weathering rinds on basaltic and andesitic stones in glacial deposits in the western United States also clearly demonstrate that rock-weathering processes slow with time. Some weathering processes appear to conform to exponential functions of time, such as the square-root time function for hydration of volcanic glass, which conforms to the theoretical predictions of diffusion kinetics. However, weathering of mineralogically heterogeneous rocks involves complex physical and chemical processes that generally can be expressed only empirically, commonly by way of logarithmic time functions. Incongruent dissolution and other weathering processes produce residues, which are commonly used as measures of weathering. These residues appear to slow movement of water to unaltered material and impede chemical transport away from it. If weathering residues impede weathering processes then rates of weathering and rates of residue production are inversely proportional to some function of the residue thickness. This results in simple mathematical analogs for weathering that imply nonlinear time functions. The rate of weathering becomes constant only when an equilibrium thickness of the residue is reached. Because weathering residues are relatively stable chemically, and because physical removal of residues below the ground surface is slight, many weathering features require considerable time to reach constant rates of change. For weathering rinds on volcanic stones in the western United States, this time is at least 0.5 my. 相似文献
7.
采用实验室恒温培养方法对三江平原3种不同土地利用类型开发后的沼泽土和草甸土进行了温度敏感性研究。研究结果表明,在5℃、15℃、25℃和35℃ 4种不同温度条件下,各土壤类型的土壤呼吸速率均随温度的升高而增大。在同一温度条件下,3种土壤呼吸强度由弱到强依次是：草甸土-旱地<草甸土-水田<沼泽土-人工林。指数模型和乘幂模型均可以较好地描述沼泽土和草甸土土壤呼吸与温度之间的关系,土壤呼吸强度随温度的升高呈指数或乘幂上升。3种土壤的Q10值呈现出随温度升高而降低的趋势,表明土壤呼吸在较低温度下的温度敏感性更高。对未添加植物残体的纯土壤组和添加了植物残体的对照组进行对比研究,发现添加植物残体后土壤呼吸强度大大增强,因此野外实际的土壤呼吸强度要比通常室内实验中去除植物残体后所测定的土壤呼吸强度更高。 相似文献
8.
塔里木盆地柯坪地区中寒武统藻白云岩去白云岩化研究 总被引：1，自引：0，他引：1
对塔里木盆地柯坪地区中寒武统去白云岩化现象进行了研究。去白云岩化限于渗透性较好的藻白云岩,并且只有靠近含膏层段的藻白云岩才发生去白云岩化。从微观上看,发生去白云岩化的藻灰岩与藻灰云岩含有明显的去白云岩化交代残余,白云石残余呈碎斑状或树枝状。树枝状白云石残余含有大量的方解石包裹体,同时具有较高的Ca/Mg比,为高钙白云石,去白云岩化较彻底,形成藻灰岩;碎斑状白云石残余成分较均一,接近化学计量白云石(Ca/Mg比接近1),去白云岩化程度较弱,形成藻灰云岩。藻灰云岩的δ18O值(平均值为-6.7‰)明显低于邻近的白云岩(平均值为-5.3‰),同时高于藻灰岩(平均值为-9.5‰)。与未发生去白云岩化的藻白云岩相比,藻灰岩与藻灰云岩的孔隙度要明显降低。 相似文献
9.
Luis Barba 《Geoarchaeology》2007,22(4):439-452
In addition to research carried out on soils and sediments, there is a parallel field of research applying the same analytical techniques to the study of chemical residues in stuccoes. The most common material used to build floors in Mesoamerica after the Classic period was lime plaster. The study of residues in stuccoes becomes, therefore, a very promising study area. In last 25 years the Archaeological Prospection Laboratory at Mexico's National Autonomous University has developed a research strategy to study human activities based on ethnoarchaeological studies to interpret the distribution of chemical residues in archaeological floors. The most successful applications have been in lime‐plastered surfaces; this article presents a brief review of these works. © 2007 Wiley Periodicals, Inc. 相似文献
10.
矿山固体废弃物包括废石和尾矿(渣),是重要的二次资源,特别是金矿山尾矿作为一种非常重要的二次矿产资源,更应受到重视。笔者以贵州省丹寨汞金矿的矿山固体废弃物为主要研究对象,对丹寨汞金矿区矿产资源开采及选冶过程中产生的尾矿资源潜力进行了现场调查,并对相关样品进行分析测试,初步掌握了尾矿(渣)资源基本情况及远景资源量,有两个尾矿(渣)堆金潜在资源量达800 kg;并根据丹寨汞和金多共(伴)生的特征,对丹寨排庭汞金矿老采空区矿硐壁围岩研究,发现其1～1. 5 m范围内,普遍含金或具有金矿化,具有找金的潜力,且初步分析了金资源潜力。简要地进行了尾矿(渣)"二次资源"、废弃矿硐的残留金资源综合利用可行性分析。 相似文献
11.
王水溶样-氢醌容量法测定碳酸盐地质样品中的金 总被引：1，自引：1，他引：0
应用王水溶样-活性炭富集金-氢醌容量法测定岩石、土壤等一般地质样品中的金时,王水溶样后经布氏漏斗抽滤后剩余的不溶物残渣中金含量小于金总量的4%,通常不计入分析结果。而碳酸盐地质样品经焙烧后在王水溶解过程中因为钙和镁的硅酸盐含量较高,形成了不溶于王水的二氧化硅凝胶及大量钙镁胶状物,包裹和吸附样品溶液中的金,造成分析过程中金的损失。本文将抽滤后的滤液和不溶物残渣分别处理,收集王水分解样品抽滤步骤后的不溶物残渣,用氢氟酸-硫酸除硅,王水溶解测定残渣中的金含量,滤液和残渣两次测试合量为样品中金含量。实验研究了不溶物残渣中的金量、金的来源以及样品中硅钙镁的含量对金测定的影响。结果表明,不溶物残渣吸附和包裹的金量占样品金总量的18%~22%,残渣中金的主要来源是已被王水溶解但被二氧化硅等胶状物包裹吸附而未进入溶液的金,其次是未被王水溶解的单质金。胶状物的形成与样品中钙镁硅含量有直接的关系,当CaCO3、MgCO3含量达到30%以上时,必须考虑残渣中的金,以保证金的测试结果准确。 相似文献
12.
我国南海海鱼中有机氯农药残留分析 总被引：3，自引：0，他引：3
建立了凝胶渗透色谱前处理,毛细管气相色谱测定我国南海海鱼中11种有机氯农药的方法。分析了油鲽鱼块、鲷鱼片、银鳕鱼、哈哈鱼块、海鳗鱼中的有机氯农药残留情况,发现在禁用20多年后,六六六(HCHs)、滴滴涕(DDTs)、狄氏剂、环氧七氯在鱼肉中均有不同程度的检出,其中滴滴涕的残留水平最高达到26.73μg/kg。研究发现我国南海海鱼中4种HCH的总残留量高于北京市场上的淡水鱼的残留水平;多数有机氯农药残留污染的平均水平也高于英国和巴西等国鱼类的水平。南海海鱼中有机氯农药残留水平具有指示环境污染的意义。 相似文献
13.
典型韵律互层式灰岩与泥灰岩的地球化学特征对比 总被引：1，自引：0，他引：1
通过对德国南部地区上侏罗统麻姆组典型韵律互层式灰岩与泥灰岩进行逐层采样,并进行不溶残余物分析和地球化学测定对比,发现两者所含非碳酸盐物质没有区别。SiO2、Al2O3、Fe2O3、K2O和TiO2等来源于陆源碎屑物,在灰岩与泥灰岩中的比例完全相同,其含量的不同完全由碳酸盐物质的稀释所引起。元素Sr、Zn、Mn和Mg归为成岩作用控制元素,最先存在形式与碳酸盐有关,但成岩阶段变化极大,Mg的含量主要受白云岩化作用程度控制。另一组元素如S、Ba、Rb和P等介于以上两组元素之间,表现为部分受陆源碎屑物含量控制,部分受成岩作用影响。研究表明,灰岩与泥灰岩韵律互层形成的原因主要是由于碳酸盐物质的沉积速率变化所致,成岩阶段的压溶作用加大了两者的差异,但这种差异只表现在于碳酸盐物质与酸不溶残余物的比例上,而地球化学组成没有本质区别。 相似文献
14.
Extraction and subsequent loss of silver from leach liquor during oxidative ammonia leaching of complex sulphide and chalcopyrite concentrates have been observed. The lost silver value from the leach liquor was unrecoverable when the residues were treated with ammonia-ammonium sulphate buffer (pH=9.5) solutions at 27°C. However, when the same slurry was heated to 75°C in an autoclave under an atmosphere of oxygen, almost all the silver value could be redissolved. The leach residues lost their silver absorbance property from ammoniacal solutions on repeatedly heating and cooling the leached slurries in the presence of oxygen. In this work, silver losses from ammoniacal solutions on various leach residues, synthetic iron oxides, and freshly precipitated Fe(II) and Fe(III) hydroxides are reported. None of the major constituents present in the leach residues were responsible for the silver losses but small amounts of Fe(II) associated with the residues could take up silver from the leach solutions. 相似文献
15.
仪器残留物对氢化物发生-原子荧光光谱法测定硒和碲的影响探讨 总被引：1，自引：1，他引：0
用氢化物发生-原子荧光光谱法(HG-AFS)分析地矿样品时,在仪器反应块、传输管路和原子化器上会有残留物生成,这些残留物中的某些成分积累到一定量时就会显著地影响硒和碲的测定.本文在分析HG-AFS法测定硒和碲干扰情况的基础上,用高纯物质配制的标准系列进行试验,避免了共存成分的影响.通过比较在仪器反应块、传输管路和原子化器更换前后标准系列的测定结果,表明仪器残留物会对硒、碲测定产生影响.对一些反应块、传输管路和原子化器的溶出物进行分析,发现钛、铜、砷、锑和铋会影响硒、碲的测定灵敏度和标准系列线性相关系数,这些元素也是文献中提到的共存成分中的干扰元素.通过更换仪器相应配件,克服了仪器残留物的影响,硒、碲的灵敏度有不同程度的提高,标准系列测试结果质量明显改善,线性相关系数均在0.9995以上.本研究认为对仪器残留物成分的分析是控制原子荧光光谱法干扰的一种有效手段. 相似文献
16.
Robert Keith Moniot 《Geochimica et cosmochimica acta》1980,44(2):253-271
Acid-resistant residues were prepared by HCl-HF demineralization of three H-type ordinary chondrites: Brownfield 1937 (H3), Dimmitt (H3,4), and Estacado (H6). These residues were found to contain a large proportion of the planetary-type trapped Ar, Kr, and Xe in the meteorites. The similarity of these acid residues to those from carbonaceous chondrites and LL-type ordinary chondrites suggests that the same phase carries the trapped noble gases in all these diverse meteorite types. Because the H group represents a large fraction of all meteorites, this result indicates that the gas-rich carrier phase is as universal as the trapped noble-gas component itself. When treated with an oxidizing etchant, the acid residues lost almost all their complement of noble gases. In addition, the Xe in at least one oxidized residue, from Dimmitt, displayed isotopic anomalies of the type known as CCFX or DME-Xe, which is characterized by simultaneous excesses of both the lightest and heaviest isotopes. The anomaly in the Dimmitt sample differs from that observed in carbonaceous-chondrite samples, however, in the relative proportions of the light- and heavy-isotope excesses.The results of this study do not show an inverse correlation between trapped and trapped 36Ar abundance, as has been reported for acid-resistant residues from LL-chondrites. The results of this work therefore fail to support the hypothesis that meteoritic trapped noble gas abundances were established at the time of condensation. 相似文献
17.
CAMPBELL S. NELSON 《Sedimentology》1977,24(1):31-52
Grain-size parameters derived from the mechanical analysis of acid-insoluble residues from mixed terrigenous-shell beach sediments from Auckland, New Zealand, are more effective for interpreting the depositional processes, and for characterizing the beach environment on textural scatter plots, than are parameters based on the analysis of the total beach samples. This results mainly from the wide variations in size of hydraulically equivalent skeletal carbonate grains in the sediment, especially in the coarser size grades, but may also be accentuated by the local origin and susceptibility to alteration of the shell material. Compared with the total sediment grain-size distribution, the insoluble residues from the beach deposits are characteristically finer-grained, better sorted, and more consistently coarse-skewed and leptokurtic. The grain-size distribution characteristics of insoluble residues from several stratigraphic units in a sequence of Oligocene mixed terrigenous-skeletal shelf sediments in the South Auckland region distinguish depositional mechanisms and environmental energy levels for each unit that are consistent with interpretations made on the basis of carbonate petrography and palaeontology. With regard to the bulk content of terrigenous mud in the insoluble residues, the grain-size distribution of the fraction coarser than 4φ is alone diagnostic of the energy-time trends in these sediments. The grain-size parameters of the acid-insoluble residues in modern and ancient mixed terrigenous-skeletal carbonate sediments may provide more reliable criteria for distinguishing and characterizing the depositional environment of these deposits than do the parameters obtained from the size distribution of the total grain population. 相似文献
18.
采用实验室恒温培养方法对三江平原3种不同土地利用类型开发后的沼泽土和草甸土进行了温度敏感性研究。研究结果表明,在50c、15℃、250C和35℃4种不同温度条件下,各土壤类型的土壤呼吸速率均随温度的升高而增大。在同一温度条件下．3种土壤呼吸强度由弱到强依次是：草甸土一旱地〈草甸土一水田〈沼泽土一人工林。指数模型和乘幂模型均可以较好地描述沼泽土和草甸土土壤呼吸与温度之间的关系,土壤呼吸强度随温度的升高呈指数或乘幂上升。3种土壤的Q14。值呈现出随温度升高而降低的趋势,表明土壤呼吸在较低温度下的温度敏感性更高。对未添加植物残体的纯土壤组和添加了植物残体的对照组进行对比研究,发现添加植物残体后土壤呼吸强度大大增强,因此野外实际的土壤呼吸强度要比通常室内实验中去除植物残体后所测定的土壤呼吸强度更高。 相似文献
19.
中国煤中的铀、钍和放射性核素 总被引：14，自引：0，他引：14
中国煤中的铀平均含量为3mg/kg,在某地富铀煤中检测到的最高值达25660mg/kg,其赋存状态主要是与有机质相结合的方式;钍平均含量6 mg/kg,没有发现异常现象.南方一些地区的石煤中含有较多的放射性核素,并且容易在灰渣中富集,综合利用时应加强监控,以避免产生危害. 相似文献
20.
Geodynamic Information in Peridotite Petrology 总被引：12，自引：1，他引：12
Systematic differences are observed in the petrology and majorelement geochemistry of natural peridotite samples from thesea floor near oceanic ridges and subduction zones, the mantlesection of ophiolites, massif peridotites, and xenoliths ofcratonic mantle in kimberlite. Some of these differences reflectvariable temperature and pressure conditions of melt extraction,and these have been calibrated by a parameterization of experimentaldata on fertile mantle peridotite. Abyssal peridotites are examplesof cold residues produced at oceanic ridges. High-MgO peridotitesfrom the Ronda massif are examples of hot residues producedin a plume. Most peridotites from subduction zones and ophiolitesare too enriched in SiO2 and too depleted in Al2O3 to be residues,and were produced by melt–rock reaction of a precursorprotolith. Peridotite xenoliths from the Japan, Cascades andChile–Patagonian back-arcs are possible examples of arcprecursors, and they have the characteristics of hot residues.Opx-rich cratonic mantle is similar to subduction zone peridotites,but there are important differences in FeOT. Opx-poor xenolithsof cratonic mantle were hot residues of primary magmas with16–20% MgO, and they may have formed in either ancientplumes or hot ridges. Cratonic mantle was not produced as aresidue of Archean komatiites. KEY WORDS: peridotite; residues; fractional melting; abyssal; cratonic mantle; subduction zone; ophiolite; potential temperature; plumes; hot ridges 相似文献