电感耦合等离子体质谱测定陶瓷器皿中微晶溶出铅镉的研究

采用电感耦合等离子体质谱(ICP-MS)法,用4%乙酸溶液萃取分离Pb、Cd,对日用瓷表面微量溶出元素Pb和Cd进行了分析。对影响其测量的各种因素进行了较为详细的研究,确定了实验的最佳测定条件。结果表明,方法的检出限为0.03(Pb)和0.02μg/L(Cd),回收率为92.79%-109.09%,RSD小于3.46%。该法准确、快速、简便,应用于日用瓷中的微量溶出铅镉的测定,结果满意。     

用氨基酸共聚物/氰桥配位聚合物修饰电极同位镀铋溶出伏安法测定微量铅、镉离子

本文在玻碳电极基底上,采用多重电化学聚合法制备了氨基酸共聚物/含钕离子杂金属氰桥配位聚合物复合修饰电极(Aminoacid copolymer/Nd(III)-Fe(III)-WO42-Cy HMCPs/GCE)。在此工作电极上,用示差脉冲伏安法研究了Pb2+、Cd2+的阳极溶出伏安行为,利用同位镀铋法解决了待测离子间的相互干扰。基于这种环境友好的伏安测定原理,建立了无汞电化学法同时测定微量Pb2+、Cd2+的新方法,可将Pb2+、Cd2+的定量检测范围扩展至四个数量级;Pb2+、Cd2+溶出峰电流值与其浓度在0.01～1.0μmol/L、1.0～100μmol/L范围内呈现两段线性关系,检出限(S/N=3)分别为4.4、3.3 nmol/L。     

ICP-MS法测定涂料中痕量重金属的研究

研究了微波消解样品，试液用电感耦合等离子体质谱(ICP-MS)法同时测定样品中Pb、As、Cd、Cr、Ni等重金属元素。对影响其测量的各种因素进行了较为详细的研究，确定了实验的最佳测定条件。结果表明，方法的检出限为0．001～0．008μg／L，回收率为91．90％～104．02％，RSD小于1．15％。     

ICP-AES法测定硼钙石中的Hg、Cd、Cr、Pb

介绍了硼钙石中Hg、Cd、Cr、Pb等元素的检测方法。通过使用HNO3-陋体系微波消解硼钙石样品,用ICP—AES测定Hg、Cd、Cr、Pb等元素。结果表明用该检测方法测定硼钙石中Hg、Cd、Cr、Pb等元素的回收率分别达到84．0％、91．096、95．5％、89．0％,该方法检出限为1．4,0．5,1．0,1．8mg／kg,满足ROSH指令的检测要求。     

阴极吸附溶出方波伏安法测定微量镉

研究了阴极吸附溶出方波伏安法测定微量镉的方法,该法不受共存离子镍、锌等的干扰。详细研究了阴极吸附溶出方波伏安法测定微量镉的最佳条件。在pH=4.50的0.2 mol.L-1HAc—NaAc缓冲体系中,Cd2 —XO配合物在汞膜电极上于-0.68 V(Vs.Ag/AgCl)处产生一灵敏的阴极吸附溶出方波伏安峰,灵敏度高,波形好。峰电流Ip与Cd2 浓度在1.5×10-7~5.0×10-6mol.L-1范围内呈良好的线性关系,相关系数为0.997 6,其检测下限为5.0×10-8mol.L-1。将该法用于水中微量镉的测定,结果较好。     

煅烧水泥熟料过程中重金属逸放的几个问题

对煅烧水泥熟料过程中重金属Hg、Pb、Cd、Zn和Cu的逸放进行了研究。Hg及其化合物在300℃时绝大部分已挥发，水泥窑中Hg的逸放率高达90％-96％。在实验电炉1400℃静置煅烧的条件下，当Pb、Cd、Zn和Cu的掺量均为0．05％时，其选放率分别为：Pb为94．50％，Cd为96．62％，Zn为43．61％，Cu为36．03％。氟会促进Ph、Cd、Zn、Cu的逸放。水泥立窑的Pb、Cd逸放率高达84％～90％；Zn和Cu的逸放率为36％-47％。     

化学修饰碳糊电极对环境水样中微量铅、镉离子的连续电化学测定

报道了用8-羟基喹啉作碳糊电极的修饰剂,测定环境体系中微量铅、镉离子的电化学方法.该电极在KNO3(pH=4.0)中,用吸附溶出伏安法测定Pb2+、Cd2+,在-0.56V(vs,SCE)和-0.84V处有灵敏溶出峰,峰电流与铅的浓度在(3.0×10-8～4.5×10-6)mol/L的范围内呈良好的线性关系,与镉的浓度在(4.0×10-8～3.5×10-6)mol/L的范围内呈良好的线性关系,该方法用于水样中铅、镉的测定,检出限为3.0×10-9mol/L(Pb2+)和5.0×10-9mol/L(Cd2+).     

ICP-MS法测定陶瓷容器中重金属元素的研究

采用电感耦合等离子体—质谱(ICP—MS)法同时测定了陶瓷容器中重金属元素PB、CA、Cr、Ni，对影响其测量的各种因素进行了较为详细的研究，确定了实验的最佳测定条件。结果表明，方法的检出限为0．002—0．008μg/L，回收率为90．0％-110．0％，RSD小于9．21％。该法准确、快速、简便，应用于陶瓷容器中重金属元素的测定，结果满意。     

DVD-Ag电极阳极溶出伏安法测定枸杞子中铅和镉残留

建立了利用DVD-Ag电极阳极溶出伏安法同时快速测定铅和镉的方法,并考察了I^-对电极上的铅和镉溶出分析的影响。利用该方法测定了枸杞子中铅和镉的残留含量。结果表明,优化实验条件下,在5～50μg/L浓度范围内,Pb-对电极上的铅和镉溶出分析的影响。利用该方法测定了枸杞子中铅和镉的残留含量。结果表明,优化实验条件下,在5～50μg/L浓度范围内,Pb⁽²⁺⁾和Cd(2+)和Cd⁽²⁺⁾的溶出峰电流与Pb(2+)的溶出峰电流与Pb⁽²⁺⁾和Cd(2+)和Cd⁽²⁺⁾的浓度呈线性相关,相关系数分别为0.992 3和0.995 3,Pb(2+)的浓度呈线性相关,相关系数分别为0.992 3和0.995 3,Pb⁽²⁺⁾和Cd(2+)和Cd⁽²⁺⁾的检出限分别为0.2μg/L和2.6μg/L(S/N=3)。对该方法进行了方法学考察,包括精密度、稳定性和回收率,结果均符合相关要求。枸杞子中Pb(2+)的检出限分别为0.2μg/L和2.6μg/L(S/N=3)。对该方法进行了方法学考察,包括精密度、稳定性和回收率,结果均符合相关要求。枸杞子中Pb⁽²⁺⁾和Cd(2+)和Cd⁽²⁺⁾的残留含量测定结果与经典的电感耦合等离子体质谱法(ICP-MS)一致性较好,表明该方法可用于枸杞子中铅和镉的残留量的检测。     

阳极溶出伏安法同时测定海水中铜、铅、镉、锌

采用微分脉冲阳极溶出伏安法同时测定了海水中Cu、Pb、Cd、Zn4种痕量元素,在选定最佳实验条件下,通过标准加入法对海水的Cu、Pb、Cd、Zn进行分析,其相对标准偏差分别为5.6%、4.6%、1.80%、1.98%,而回收率分别为98.0%～105.6%、95.3%～106.5%、90.0%～107.4%和90.8%～103.5%,测定结果令人满意。     

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。