电感耦合等离子体质谱法测定铅锌矿中镓铟锗铊

稀散元素是铅锌矿石中重要的伴生元素,为了综合利用铅锌矿资源,在地质、选矿上经常要考查稀散元素镓、锗、铟、铊的含量。研究了利用电感耦合等离子体质谱法测定铅锌矿中镓、铟、锗、铊4种稀散元素,选取了最佳仪器分析条件,通过在线加入内标校正基体效应和接口效应,检出限分别为0.02μg·g-1、0.01μg·g-1、0.03μg·g-1和0.05μg·g-1,相对标准偏差(RSD)为0.85%~2.84%,回收率在93.3%~102.3%之间,明显优于其他分析方法。该方法样品前处理简便、快捷,测定结果准确,令人满意。     

电感耦合等离子体质谱法测定锶矿石中Th、U、Mo、Cu、Pb、Zn、Ni、Cr

为了综合利用锶矿资源,在地质、选矿上经常要考查伴生的微量元素Th、U、Mo、Cu、Pb、Zn、Ni、Cr等的含量。研究利用电感耦合等离子体质谱法测定锶矿石中Th、U、Mo、Cu、Pb、Zn、Ni、Cr,选取了最佳仪器分析条件,检出限分别为0.019μg·g-1、0.007μg·g-1、0.01μg·g-1、0.08μg·g-1、0.37μg·g-1、0.14μg·g-1、0.08μg·g-1、0.35μg·g-1,相对标准偏差(RSD)为0.94%~3.41%,方法回收率在95.6%~103.1%之间。该方法具有前处理过程简单、引入干扰少、准确度、精密度、检出限满足要求,同时具有线性范围广、测试速度快等特点,适合锶矿石中Th、U、Mo、Cu、Pb、Zn、Ni、Cr等元素的测定。     

偏硼酸锂熔融ICP-OES测定锶矿石标准物质中锶钡方法的探讨

研究利用偏硼酸锂熔融ICP-OES法快速测定锶矿石标准物质中锶、钡含量,选取了最佳仪器分析条件,锶、钡的检出限分别为0.45μg·g-1、0.80μg·g-1,相对标准偏差(RSD)为0.43%~1.94%,回收率在97.7%~104.6%之间。该方法样品前处理简便、快捷,测定结果准确,能够满足日常生产检验要求。     

氢化物发生-原子荧光光谱法同时测定环境水样中的砷和硒

采用HNO_3-H_2O_2消解液消解环境水样,建立了一种顺序注射氢化物发生-原子荧光光谱法同时测定环境水样中砷和硒含量的方法。讨论了光电倍增管负高压、原子化器高度、载气流量、屏蔽气流量、砷和硒灯电流等因素对测定结果的影响。结果显示,砷和硒的相对标准偏差均小于5%,检出限分别为0.20μg·L~(-1)和0.20μg·L~(-1),加标回收率分别为95.0%~108%和90.0%~120%。该方法简单快速,灵敏度高,样品测定结果准确可靠,适用于河水、井水、废水等环境水样中砷和硒的测定。     

HPLC-ELSD同时测定知母药材中3种主要皂苷含量

目的:首次建立同时测定知母药材中3种主要皂苷含量的HPLC-ELSD法。方法:采用Diamonsil C18(2)柱(250×4.6mm,5um),流动相为甲醇(A)-水(B),梯度洗脱;流速1.0m L·min~(-1);柱温30℃;蒸发光散射检测器雾化器流速2.0L·min~(-1);漂移管温度50℃;进样量10u L。结果:知母皂苷O、知母皂苷BII、知母皂苷BI浓度分别在64.13~1026μg·mL~(-1)(r=0.9989)、57.15~1028μg·mL~(-1)(r=0.9965)、67.32~1077μg·mL~(-1)(r=0.9998)的范围内呈良好的线性关系。加样回收率平均值为99.43%~102.8%,RSD为1.78%~2.58%。结论:该含量测定方法简便,准确,可靠,能同时测定知母皂苷O、知母皂苷BII、知母皂苷BI 3种有效成分含量。     

微波消解-AAS法测定当归中6种元素的含量

测定当归中Cu、Fe、Mn、Zn、Pb、As 6种元素的含量,为当归的现代研究提供依据。本实验采用微波消解法处理当归,采用火焰原子吸收法测定Cu、Fe、Mn、Zn 4种元素的含量,采用石墨原子吸收法测定Pb、As 2种元素的含量。结果表明,当归中Cu、Fe、Mn、Zn、Pb、As 6种元素的含量分别为4.95μg·g~(-1)、333.65μg·g~(-1)、7.75μg·g~(-1)、13.34μg·g~(-1)、0.68μg·g~(-1)、0.56μg·g~(-1)。该方法快捷、简单、准确,加标回收率在97.4%~111.43%之间,RSD在0.38%~1.88%之间。     

水体除砷材料的筛选及其化学成分特征研究

为筛选适合于水体除砷的材料,比较研究了26种不同材料对水体砷的去除效果及其矿物元素含量。研究结果表明,采用水与矿物质量比为100、砷的质量浓度0.200 mg·L-1、震荡时间1 h条件下,纳米二氧化钛类矿物对水体As(V)和As(III)去除率达90%以上,效果最好;其次是活性氧化铝和宜昌锰矿粉,去除率在80%～90%;而最差的是斜发沸石和金红石,去除率低于40%。一些矿物含有污染元素,如铁矿渣和铁精粉(初)中砷的质量分数分别达到478和202μg·g-1,远高于其他矿物。铜含量最高的矿物是宜昌锰矿粉、铁矿渣、铁精粉(初)(Cu的质量分数分别为7460、2 884、3 378μg·g-1);铁矿渣的锌含量(质量分数28 030μg·g-1)最高。同一类型的矿物元素含量差异显著,如VK-T01二氧化钛中砷的质量分数高达91μg·g-1,而VK-T25H二氧化钛、VK-TA18H二氧化钛和P25二氧化钛砷的质量分数仅3～6μg·g-1;膨润土ZJL中砷、钾、钠、锌的含量远高于膨润土原矿1 6pu红和膨润土原矿1 6pu白。结果说明,矿物除砷效果和污染元素含量差别很大,应根据实际测定结果谨慎选用。     

偏硼酸锂熔融-电感耦合等离子体质谱法测定地质样品中钽、铌

应用偏硼酸锂熔融方法分解样品,通过超声波清洗器溶解试样,在5%王水介质中通过电感耦合等离子体质谱直接测定岩石中的钽、铌。本方法检出限Nb为0.11μg·g-1;Ta为0.045μg·g-1。方法回收率在95.6%~104.4%之间,方法精密度(RSD%)在0.79%~6.59%之间。该方法具有检出限低、操作简单、精密度高、准确度高、分析快速等特点,适合地质样品中钽、铌的测定。     

三波长分光光度法测茄子中总黄酮含量

采用以AlCl_3为显色的芦丁为标准物质三波长分光光度法测定茄子中的总黄酮含量,方法有效地消除了吸收峰不对称及干扰组分对定量分析造成的影响。分别在波长为λ_1=500nm,λ_2=423nm,λ_3=350nm处测吸光度时,则ΔA与浓度C之间呈良好的线性关系线性,方程为ΔA=0.0002C(μg·mL~(-1))-0.0139,R~2=0.9988,线性范围为0~3380μg·mL~(-1)。按标准曲线法进行定量分析,测得总黄酮量紫茄子为48.3 mg·g~(-1)及绿茄子为27.8mg·g~(-1),方法回收率为96.9%~102%,相对标准偏差3.66%~4.65%(n=6)。该方法操作简单,易于操作,可为果蔬总黄酮含量的测定提供理论基础。     

高效液相色谱法检测塘鲺鱼中的黄体素

采用丙酮萃取、低温去除脂肪的提取方法,建立了一种测定塘鲺鱼中的黄体素含量的高效液相色谱(HPLC)分析方法。实验结果表明,黄体素在0.646~4.525μg·mL~(-1)范围内呈良好的线性关系(r=0.9999);平均回收率为96.5%~100.8%,相对标准偏差为0.13%,方法检出限为6.464μg·L~(-1),定量限为16.16μg·L~(-1),该方法准确度和精密度均比较高,峰形和峰分离度较好,能够满足塘鲺鱼体色中的黄体素含量的检测要求。     

Insect antifeedant properties of anthranoids from the genusVismia

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.     

Direct observation of freeze-thaw instability of latex coatings via high pressure freezing and cryogenic SEM

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.     

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.     

Methyl 2,4,6-decatrienoates Attract Stink Bugs and Tachinid Parasitoids

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.     

2007～2008年世界塑料工业进展

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.     

2005～2006年国外塑料工业进展

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。