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建立了一种离子色谱法同时测定地下水中的F-、Cl-、NO3-和SO24-。以Na2CO3-NaHCO3作流动相,自动进样器进样,待测离子经阴离子交换柱分离,抑制电导检测,外标法定量。在优化的实验条件下,该方法线性相关性好(γ2>0.9992),灵敏度高,检出限在0.01~0.05 mg/L范围内,精密度好(RSD<2.43%)。测定了地下水中多种阴离子的含量,并进行加标回收试验,回收率在92.7%~104.7%之间,结果令人满意。该方法操作简单、速度快、准确度高,适合批量样品中多种阴离子成份的同时测定。 相似文献
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本文通过研究,建立了用离子色谱法同时测定液碱中Cl-、S042-含量的分析方法。选择的色谱条件:采用亲水性较强的阴离子交换分离柱分离,电导检测器,碳酸钠和碳酸氢钠混合淋洗液淋洗。样品经前处理及过H型预处理柱后直接进样测定。该方法各元素均具有良好的线性范围(Cl-在0~500μg/mL范围内相关系数为0.9999;S042-在0~50μg/mL范围内相关系数为0.9999),样品加标回收率Cl-为94.1%~113.3%;S042-在93.4%~118.2%之间,通过对3个样品的11次测定,相对标准偏差分别为Cl-0.79%~1.70%,S042-1.53%~3.90%之间该方法主要用于化工产品液碱中Cl-、S042-含量的快速分析,方法操作简便,可满足化工厂液碱产品中Cl-、S042-离子的快速检测要求,所测结果令人满意。 相似文献
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利用美国戴安公司免试剂离子色谱系统(ICS-5000系统),采用KOH梯度离子色谱法和抑制电导检测器,建立了同时测定酱油中C1-、NO2-、NO3-等三种重要的阴离子的分析方法。研究了酱油中C1-、NO2-、NO3-等三种阴离子的色谱分析条件,建立了6-8-50-6 mmol/L的KOH梯度淋洗程序,流速为0.8 mL/min。结果表明:该方法回归方程的线性相关系数达到0.999以上,各组分的检出限在0.005~0.02 mg/L之间,回收率在90.3%~103.2%之间。用本方法测定酱油中C1-、NO2-、NO3-等三种阴离子的分析,简便、实用,并且快速、准确,所得结果令人满意。 相似文献
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建立了离子色谱法测定焦化废水中多种阴离子的方法.比较了液液萃取、真空抽滤、固相萃取3种处理方法.用电导检测器同时测定了焦化废水中的F-、Cl-、N02-、N03-、PO43--含量.离子色谱法的回收率为69%~110%,相对标准偏差为0.13%~3.6%. 相似文献
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建立一种离子色谱法测定电子级试剂-四甲基碳酸氢铵中痕量的HCOO-、Cl-、NO3-的定量分析方法。使用IonPac AS11-HC型分析柱和IonPac AG11-HC型保护柱,KOH淋洗液进行梯度淋洗,流速为1.0mL/min,进样体积为100μL。在优化条件下,各离子的最低检出限为0.021~0.050mg/L,保留时间、峰面积于峰高的相对标准偏差均小于2.415%,各离子相关系数均大于0.9990。该方法前处理操作简单、准确,并且有较好的重现性和较低的检出限,可应用于四甲基碳酸氢铵中的3种痕量阴离子的同时测定。 相似文献
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焦化废水是典型的含有高浓度有机污染物的难降解的废水。为了有效的处理焦化废水,通过向焦化废水中加入适量的FeS04和CaCO3固体,达到去除一定C0D、NH3-N和色度的目的。结果表明,向l L废水中投加1 g的FeS04和0.2g的CaC03固体对焦化废水的COD、NH3-N和色度的去除能够达到一定的效果,C0D、NH3一N和色度的去除率分别为79.7%、69.7%和8O%~90%。此方法处理后的水质稳定,还可提高废水可生化性,为后续生物处理创造良好的条件。 相似文献
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建立了用单柱阴离子色谱测定水源地水中的F-、CI-、NO-2、PO43-、NO3-五种阴离子的方法。采用NJ-SA-4A阴离子交换柱、0.35mmol/LNaCO3和0.05mmol/LNaHCO3混合溶液为流动相、电导检测器在11min内完成五种阴离子的测定。该法具有良好的线性相关性和重复性(相对标准偏差2.18-4.33%),回收率为93-109.5%。方法简便实用,用于实际样品分析,所得结果令人满意。 相似文献
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在自来水消毒后往往会有微量有毒氯酸盐、溴酸盐带入。采用离子色谱方法测定自来水中ClO3-、BrO3-。采用Shodex IC SI-52 4E阴离子分离柱;3.6 mmol/L碳酸钠为淋洗液;流速为0.7 mL/min;进样量20μl;可在1 h内同时分离ClO3-、BrO3-两种阴离子。结果表明:两种离子线性范围均为9.4~1 000μg/L;相关系数在0.998 0以上;BrO3-,ClO3-的检出限分别为:8.4μg/L,4.1μg/L;加标回收率在89.0%~99.0%之间。该方法灵敏度高、重现性好、选择性高,可应用于实际水样的测定。 相似文献
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M. S. J. Simmonds W. M. Blaney F. Delle Monache M. Marquina Mac-Quhae G. B. Marini Bettolo 《Journal of chemical ecology》1985,11(12):1593-1599
Vismiones and ferruginins, representatives of a new class of lypophilic anthranoids from the genusVismia were found to inhibit feeding in larvae of species ofSpodoptera, Heliothis, and inLocusta migratoria. 相似文献
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Cheng-Le Zhao Shane Porzio Alan Smith Haiyan Ge H. T. Davis L. E. Scriven 《Journal of Coatings Technology and Research》2006,3(2):109-115
Despite its industrial importance, the subject of freeze-thaw (F/T) stability of latex coatings has not been studied extensively.
There is also a lack of fundamental understanding about the process and the mechanisms through which a coating becomes destabilized.
High pressure (2100 bar) freezing fixes the state of water-suspended particles of polymer binder and inorganic pigments without
the growth of ice crystals during freezing that produce artifacts in direct imaging scanning electron microscopy (SEM) of
fracture surfaces of frozen coatings. We show that by incorporating copolymerizable functional monomers, it is possible to
achieve F/T stability in polymer latexes and in low-VOC paints, as judged by the microstructures revealed by the cryogenic
SEM technique. Particle coalescence as well as pigment segregation in F/T unstable systems are visualized. In order to achieve
F/T stability in paints, latex particles must not flocculate and should provide protection to inorganic pigment and extender
particles. Because of the unique capabilities of the cryogenic SEM, we are able to separate the effects of freezing and thawing,
and study the influence of the rate of freezing and thawing on F/T stability. Destabilization can be caused by either freezing
or thawing. A slow freezing process is more detrimental to F/T stability than a fast freezing process; the latter actually
preserves suspension stability during freezing.
Presented at the 82nd Annual Meeting of the Federation of Societies for Coatings Technology, October 27–29, 2004 in Chicago,
IL. Tied for first place in The John A. Gordon Best Paper Competition. 相似文献
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Ethanol and (−)-α-Pinene: Attractant Kairomones for Bark and Ambrosia Beetles in the Southeastern US
In 2002–2004, we examined the flight responses of 49 species of native and exotic bark and ambrosia beetles (Coleoptera: Scolytidae
and Platypodidae) to traps baited with ethanol and/or (−)-α-pinene in the southeastern US. Eight field trials were conducted
in mature pine stands in Alabama, Florida, Georgia, North Carolina, and South Carolina. Funnel traps baited with ethanol lures
(release rate, about 0.6 g/day at 25–28°C) were attractive to ten species of ambrosia beetles (Ambrosiodmus tachygraphus, Anisandrus sayi, Dryoxylon onoharaensum, Monarthrum mali, Xyleborinus saxesenii, Xyleborus affinis, Xyleborus ferrugineus, Xylosandrus compactus, Xylosandrus crassiusculus, and Xylosandrus germanus) and two species of bark beetles (Cryptocarenus heveae and Hypothenemus sp.). Traps baited with (−)-α-pinene lures (release rate, 2–6 g/day at 25–28°C) were attractive to five bark beetle species
(Dendroctonus terebrans, Hylastes porculus, Hylastes salebrosus, Hylastes tenuis, and Ips grandicollis) and one platypodid ambrosia beetle species (Myoplatypus flavicornis). Ethanol enhanced responses of some species (Xyleborus pubescens, H. porculus, H. salebrosus, H. tenuis, and Pityophthorus cariniceps) to traps baited with (−)-α-pinene in some locations. (−)-α-Pinene interrupted the response of some ambrosia beetle species
to traps baited with ethanol, but only the response of D. onoharaensum was interrupted consistently at most locations. Of 23 species of ambrosia beetles captured in our field trials, nine were
exotic and accounted for 70–97% of total catches of ambrosia beetles. Our results provide support for the continued use of
separate traps baited with ethanol alone and ethanol with (−)-α-pinene to detect and monitor common bark and ambrosia beetles
from the southeastern region of the US. 相似文献
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Halyomorpha halys (Stål) (Pentatomidae), called the brown marmorated stink bug (BMSB), is a newly invasive species in the eastern USA that is rapidly spreading from the original point of establishment in Allentown, PA. In its native range, the BMSB is reportedly attracted to methyl (E,E,Z)-2,4,6-decatrienoate, the male-produced pheromone of another pentatomid common in eastern Asia, Plautia stali Scott. In North America, Thyanta spp. are the only pentatomids known to produce methyl 2,4,6-decatrienoate [the (E,Z,Z)-isomer] as part of their pheromones. Methyl 2,4,6-decatrienoates were field-tested in Maryland to monitor the spread of the BMSB and to explore the possibility that Thyanta spp. are an alternate host for parasitic tachinid flies that use stink bug pheromones as host-finding kairomones. Here we report the first captures of adult and nymph BMSBs in traps baited with methyl (E,E,Z)-2,4,6-decatrienoate in central Maryland and present data verifying that the tachinid, Euclytia flava (Townsend), exploits methyl (E,Z,Z)-2,4,6-decatrienoate as a kairomone. We also report the unexpected finding that various isomers of methyl 2,4,6-decatrienoate attract Acrosternum hilare (Say), although this bug apparently does not produce methyl decatrienoates. Other stink bugs and tachinids native to North America were also attracted to methyl 2,4,6-decatrienoates. These data indicate there are Heteroptera in North America in addition to Thyanta spp. that probably use methyl 2,4,6-decatrienoates as pheromones. The evidence that some pentatomids exploit the pheromones of other true bugs as kairomones to find food or to congregate as a passive defense against tachinid parasitism is discussed. 相似文献
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中蓝晨光化工研究院有限公司《塑料工业》编辑部 《塑料工业》2009,37(3)
收集了2007年7月~2008年6月世界塑料工业的相关资料,介绍了2007~2008年国外塑料工业的发展情况,提供了世界塑料产量、消费量及全球各类树脂的需求量及产能情况.按通用热塑性树脂(聚乙烯、聚丙烯、聚苯乙烯、聚氯乙烯、ABS树脂)、工程塑料(尼龙、聚碳酸酯、聚甲醛、热塑性聚酯、聚苯醚)、特种工程塑料(聚苯·硫醚、液晶聚合物、聚醚醚酮)、通用热固性树脂(酚醛、聚氨酯、不饱和聚酯树脂、环氧树脂)不同品种的顺序,对树脂的产量、消费量、供需状况及合成工艺、产品应用开发、树脂品种的延伸及应用的进一步扩展等技术作了详细介绍. 相似文献
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中蓝晨光化工研究院《塑料工业》编辑部 《塑料工业》2007,35(3):1-25,67
收集了2005年7月~2006年6月国外塑料工业的相关资料,介绍了2005—2006年国外塑料工业的发展情况。提供了世界塑料产量、消费量及全球各类树脂生产量以及各国塑料制品的进出口情况。作为对比,介绍了中国塑料的生产情况。按通用热塑性树脂(聚乙烯、聚丙烯、聚苯乙烯、聚氯乙烯、ABS树脂)、工程塑料(聚酰胺、聚碳酸酯、聚甲醛、热塑性聚酯、聚苯醚)、通用热固性树脂(酚醛、聚氨酯、不饱和树脂、环氧树脂)、特种工程塑料(聚苯硫醚、液晶聚合物、聚醚醚酮)的品种顺序,对树脂的产量、消费量、供需状况及合成工艺、产品开发、树脂品种的延伸及应用的扩展作了详细的介绍。 相似文献