非标记适体-金纳米检测尿中痕量腺苷

在pH 4.6 BR缓冲溶液中,腺苷与腺苷适体特异性结合,金纳米不被腺苷适体保护而在高盐浓度下聚集,导致共振光散射强度增强,且在1.9×10-12～2.0 ×10-11 mol/L范围内,体系共振光散射强度的增强值（ΔI）与腺苷浓度呈良好线性关系,其回归方程为ΔI=71.3＋17.0c（×10-12mol/L）,r=0.994 8,检出限为5.7×10-13 mol/L,相对标准偏差（RSD）为1.48％～ 3.70％.用于尿样中腺苷的测定,回收率在97.1％～102.8％.该方法简单、快速、灵敏.     

邻羟基苯基荧光酮共振瑞利散射法测量蛋白质含量

在pH 8.81的缓冲溶液中,邻羟基苯基荧光酮和牛血清白蛋白结合可使邻羟基苯基荧光酮的光散射信号增强,并且与蛋白质浓度在一定的范围内呈线性关系.据此,运用共振光散射技术,建立了蛋白质定量测定的方法.该方法简单、快速、灵敏,测定牛血清白蛋白的线性范围为1.1×10-6～2.0×10-6 mol/L,检出限为2.9×10-9 mol/L,对合成样品的测定结果令人满意.     

孔雀石绿-碘化钾体系共振光散射法测定水中痕量汞

研究了一种共振光散射法测定水中痕量汞的新方法。在稀硫酸介质中,KI和Hg2+形成[Hg I4]2-,与碱性阳离子染料孔雀石绿结合形成离子缔合物,使体系共振散射强度增强,并且增强程度与Hg2+浓度(在4.20×10-8⁸.0×10-7mol/L范围内)呈现良好的线性关系。方法检出限为1.26×10-8mol/L,将该方法用于环境水中汞的测定,加标回收率为102.0%8.0×10-7mol/L范围内)呈现良好的线性关系。方法检出限为1.26×10-8mol/L,将该方法用于环境水中汞的测定,加标回收率为102.0%¹06.8%,操作简便、快速,结果准确可靠。     

孔雀石绿-碘化钾体系共振光散射法测定水中痕量汞

研究了一种共振光散射法测定水中痕量汞的新方法。在稀硫酸介质中,KI和Hg2+形成[Hg I4]2-,与碱性阳离子染料孔雀石绿结合形成离子缔合物,使体系共振散射强度增强,并且增强程度与Hg2+浓度(在4.20×10-8~8.0×10-7mol/L范围内)呈现良好的线性关系。方法检出限为1.26×10-8mol/L,将该方法用于环境水中汞的测定,加标回收率为102.0%~106.8%,操作简便、快速,结果准确可靠。     

8-羟基喹啉-5-磺酸共振光散射法测定铅

在pH 5.0 BR缓冲液及阳离子表面活性剂CTMAB存在下,8-羟基喹啉-5-磺酸与Pb2+相互作用形成配合物,导致体系的共振光散射(RLS)强度增强,且在8.01×10-8～1.2×10-5mol/L范围内,体系ΔI强度与Pb2+的浓度有良好的线性关系,其回归方程为:ΔF=–91.23+61.21c(×10-6mol/L),相关系数r=0.997 6,检出限为2.40×10-8mol/L,相对标准偏差(RSD)在2.15%～4.01%。用于环境中水样的测定,回收率在96.3%～99.6%。该方法简单、快速、灵敏度高。     

铜(Ⅱ)-曙红B-洛美沙星的共振瑞利散射的研究与应用

在pH 4.0的BR缓冲介质中,洛美沙星能与铜(Ⅱ)形成螯合阳离子,再通过静电引力和疏水作用,与曙红B阴离子形成缔合物,导致共振瑞利散射(RRS)显著增强。在最大RRS峰380 nm处,散射光增强值(ΔI)与洛美沙星的浓度成正比,据此建立了共振光散射法测定洛美沙星,线性范围为8.99×10-8～3.00×10-6mol/L,检出限(3Sb/k)为2.69×10-8mol/L。该法用于检测牛奶中洛美沙星的含量,并取得满意结果。该方法简单、快速、灵敏度高。     

钨酸钠共振光散射法测定维多利亚蓝B

在pH=5.33缓冲溶液中,维多利亚蓝B(Victoria blue)与钨酸钠作用并产生以281 nm和373 nm为特征峰的共振光散射(RLS)增强信号。在上述特征波长下测定的增强共振光散射强度(ΔIRLS)与维多利亚蓝B浓度在一定范围内呈线性关系。当钨酸钠浓度为4.0×10-5mol/L时,维多利亚蓝B的检出限可分别达8.74 nmol/L和10.77 nmol/L。据此建立了痕量维多利亚蓝B的共振光散射分析方法。     

吖啶红-碘化钾体系共振光散射法测定水中痕量铅

在20 mmol/L的硫酸溶液中,铅(Ⅱ)与过量的碘化钾形成[PbI4]2-配阴离子,再与碱性阳离子染料吖啶红形成离子缔合物,产生稳定增强的共振光散射,其最大RLS波长位于420 nm处,在5.16×10-8～8.0×10-7mol/L范围内,Pb(Ⅱ)浓度与RLS强度ΔI成正比,检出限为1.55×10-8mol/L。该方法灵敏、反应条件温和、易操作,适用于环境水样中铅的测定。     

溴酸钾-荧光黄-双酚A体系的共振光散射研究及其应用

建立了一种新的共振光散射法检测水中双酚A(BPA)的方法。水样中依次加入0. 60 m L硫酸溶液(0. 10 mol/L)、0. 50 m L荧光黄溶液(1. 0×10-4mol/L)、0. 40 m L溴酸钾溶液(0. 10 mol/L),70℃水浴加热反应15 min,流动自来水冷却(以终止反应),在489 nm处测定共振光散射强度。结果表明,体系共振光散射强度的增大值(ΔI)与BPA含量在0. 04～4. 60μg/m L范围内成正比,线性回归方程为ΔI=8 842. 4c+1 328. 7,r=0. 999 3。方法的检出限为0. 019μg/m L,回收率为97. 5%～103%,RSD为2. 51%～4. 98%。在1μg/m L的BPA存在下,2 000倍的Na+,1 000倍的CO32-,300倍Ca~(2+)、Al~(3+),150倍Cu~(2+)、Cd~(2+)、SO_4~(2-),50倍Cl~-,10倍的苯酚、间二苯酚、对苯二酚、Pb~(2+)不干扰测定。该方法操作步骤简单,检测灵敏度高,适用于水中BPA的检测。     

钨酸钠共振光散射法测定维多利亚蓝B

在pH=5.33缓冲溶液中,维多利亚蓝B （ Victoria blue）与钨酸钠作用并产生以281 nm和373 nm为特征峰的共振光散射（ RLS）增强信号。在上述特征波长下测定的增强共振光散射强度（△IRLS ）与维多利亚蓝B浓度在一定范围内呈线性关系。当钨酸钠浓度为4.0×10^-5 mol/L时,维多利亚蓝B的检出限可分别达8.74 nmol/L和10.77 nmol/L。据此建立了痕量维多利亚蓝B的共振光散射分析方法。     

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。