偶氮氯膦Ⅲ探针吸收光谱法测定药物中的卡马西平

建立了简便、快速、准确测定卡马西平的单波长和双波长可见吸收光谱法,探讨了反应条件、共存物质的影响及光谱特征。在弱酸性溶液中,偶氮氯膦Ⅲ与卡马西平以静电引力结合生成具有2个正吸收峰的离子缔合物,最大和次大正吸收波长分别为614 nm和666 nm,在此2个波长处,卡马西平的质量浓度在0~4.7 mg/L范围内与吸光度A呈线性关系,服从朗伯-比尔定律,表观摩尔吸光系数(κ)分别为1.58×10~4L/(mol·cm)(614 nm)和1.20×10~4L/(mol·cm)(666 nm)。用双波长叠加法测定时,其表观摩尔吸光系数(κ)达2.78×10~4L/(mol·cm),方法的回收率为98.0%~102%,相对标准偏差RSD(n=5)为2.3%~2.7%。该方法可用于药片中卡马西平的测定。     

阿拉伯树胶增敏-新试剂对碘偶氮氯膦与铋离子显色反应的研究与应用

在pH =2 0的HCl-HAc介质中 ,对碘偶氮氯膦与Bi3 + 生成蓝紫色的配合物 ,其最大吸收波长的位置在 6 84nm ,摩尔吸光系数为 1 15× 10 4,Bi3 + 浓度在 0～ 5mg/L范围内符合比尔定律。表面活性剂具有增敏作用 ,在测定条件下 ,加入 0 5 %的阿拉伯树胶 2mL ,其线形回归方程为c =- 1 0 74 +3 5 5 7A(mg/L)。     

对三氟甲基偶氮氯膦与铁(Ⅲ)显色反应及在离子膜制碱质量控制中的应用

研究了新合成试剂对三氟甲基偶氮氯膦与 Fe3+离子的显色反应 ,在 p H=1 .0的 HCl介质中 ,对三氟甲基偶氮氯膦与 Fe3+离子生成紫红色的配合物 ,其最大吸收波长的位置在 6 6 9nm,摩尔吸光系数为 1 .7× 1 0 5,铁离子浓度在 0～ 0 .3 mg/L范围内符合比尔定律 ,将之用于离子膜制碱过程精制盐水中铁的测定 ,方法灵敏度、准确度高 ,测定干扰少 ,其结果令人满意。     

偶氮氯膦I光度法测定粘土中低含量的氧化钙和氧化镁

将酸溶试样蒸干 ,铜试剂和三乙醇胺掩蔽分离铁、铝、锰等干扰元素。在pH =1 0 5缓冲溶液中偶氮氯膦I光度法测定中低含量的氧化钙和氧化镁。在最大吸收波长 590nm处钙和镁有相同的摩尔吸光度。测定A1,再加入 3 0 0ml,EGTA Pb溶液使钙络合物颜色消退 ,测吸光度A2 (相当于Mg量 ) ,据 (A1-A2 )从曲线上查钙量。钙 :4～ 80 μg/50ml,镁 4～ 6 0 μg/50ml,符合比尔定律。     

矩阵换算分光光度法中两种计算方法的比较

研究了在pH为10．5的硼砂—氢氧化钾缓冲溶液和乙醇的增敏作用条件下，偶氮氯膦I与钙镁的吸收特性，建立了多波长吸光光度法同时测定钙镁的方法。采用两种矩阵算法对实验数据进行处理，并对结果进行比较和分析。钙镁质量浓度在0—1mg／L范围内用方法2能得到准确结果。     

新显色剂2-(2-噻唑偶氮)-5-[(N,N-二羧甲基)氨基]苯磺酸与钯显色反应的研究及其应用

合成了新试剂 2 - ( 2 -噻唑偶氮 ) - 5 - [( N,N-二羧甲基 )氨基 ]苯磺酸 ( TADCABS) ,并研究了其与钯 ( )的显色反应。在 0 .4mol·L- 1 HCl O4介质中 ,TADCABS与钯 ( )反应生成稳定的 1∶ 1蓝色水溶性配合物 ,其最大吸收波长为 6 4 1 .8nm,钯量在 0～ 1 .6 μg·m L- 1 范围内符合比耳定律。用双波长测定 ,表观摩尔吸光系数 ε641 .8;52 2 =7.4× 1 0 4 L· mol- 1 · cm- 1 ,大量的其他金属离子共存时 ,不经预分离也无需掩蔽剂可直接测定铂钯催化剂中的微量钯。操作简便 ,结果令人满意。     

三溴偶氮氯膦在微量钯流动注射分光光度法测定中的应用

基于三溴偶氮氯膦可与钯在硫酸介质中形成易溶于水的蓝紫色络合物的这一显色反应,建立了测定微量钯的流动注射光度分析法。络合物的吸收波长为617nm。最佳显色反应条件是1.5～4.0mol/L H_2SO_4,0.020%的三溴偶氮氯膦溶液,反应温度80±1℃。大量的贵金属离子和常见的金属离子均不干扰测定。钯的线性范围为0～7.0μg/mL。检出限为0.1μg/mL 钯。用以不经分离直接测定二次阳极泥中的钯,结果良好。     

水泥生、熟料中含铬量的偶氮氯膦-mA光度法测定

本文研究了偶氮氯膦—mA(CPA—mA)与铬(Ⅲ)的显色反应条件,选择634um为测定波长,铬量在0～12μg/25ml范围内符合比耳定律,表现摩尔吸光系数ε=2.9×10~4l·mol~(-1)·cm~(-1)。本法用于含铬水泥生料及熟料中铬的测定,结果准确。     

新显色剂1-（4-硝基苯基）-3-（4-硝基-噻唑）-三氮烯的合成及其与汞的显色反应

报道了1-（4-硝基苯基）-3-（4-硝基-噻唑）-三氮烯（NPNTT）的合成及其与汞的显色反应。在OP存在下,pH10．5的Na28407-NaOH缓冲溶液中．该试剂能与汞发生显色反应,汞与NPNTT形成摩尔比为1：5型的配合物,在450nm处有一最大正吸收峰,在540nm处有一最大负吸收。以450nm为参比波长,540m＇n为测量波长进行双波长测定,表观摩尔吸光系数为2．58×10^5L·mol·1．cm^-1汞的浓度在0-560μg/L范围内符合比尔定律。用拟定方法测定废水中的微量汞,结果满意。     

阴离子交换树脂分离双波长分光光度法测定铅

在 p H7.5～ 9.0的缓冲介质中 ,铅与 5 - Br- PADAP形成稳定的红色三元胶束络合物 ,以 440 nm为参比波长 ,5 70 nm为测定波长 ,可用双波长法测定微量铅 ,表观摩尔吸光系数为ε=1 .0× 1 0 5L· mol- 1· cm- 1,铅的浓度在 0～ 1 .6mg· L- 1范围内符合比尔定律。本法用于矿样中微量铅的测定 ,结果较满意     

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。