佛尔哈德法测定2-甲基-5-硝基咪唑

在碱性溶液中用硝酸银沉淀2-甲基-5-硝基咪唑，过滤除去沉淀后酸化溶液，用硫氰酸铵标准溶液滴定过量的硝酸银。方法用于2个样品的测定，结果满意，5次平行测定相对标准偏差为0．18％。     

Fe^3＋、Zn^2＋共存、Mn^2＋、Cu^2＋、Ca^2＋体系中Ca^2＋、Mg^2＋、Mg^2＋等离子的测定

叙述了Fe^3 、Zn^2 、Mn^2 、Cu^2 、Ca^2 、Mg^2 等离子共存体系中采用六次甲基四胺一铜试剂沉淀除去Fe^3 、Zn^2 、Mn^2 、Cu^2 等干扰离子．用EDTA滴定钙镁的方法，该方法钙的回收率在99．7％～100．3％；镁的回收率在100．0％～100．4％，标准偏差为0．022。     

石灰法生产镓的镓沉淀中碳碱的测定

提出了一种适合镓沉淀样品中测定碳碱的方法。该方法依据酸碱反应的原理,用硫酸把样品中的碳碱以二氧化碳的形式赶出,碱液吸收。分别用酚本和甲基凛批示剂,盐酸返滴定。利用利本方法对长铝公司镓车间提供的镓三次沉淀六个样品进行了１２次测定,其相对标准偏差为０．１３％～０．３４％;通过加入标准碳酸钙进行回收试验,其回收结果与加入碳酸钙的量相吻合,加标回收率为９９．７～１００．７％。     

花炮混合药物分析方法研究

5．1 取1mL试液A于离心试管中，加入2滴冰醋酸(AR)，0．5mL硫酸钙饱和溶液，如有浑浊产生，离心沉淀，弃去上层清液，用1mL蒸馏水洗涤一次后，加入5滴硫酸(1 5)溶液，振摇，白色沉淀溶解后，加入0．5mL蒸馏水，加入1滴高锰酸钾(2g／L)溶液，加入1滴硫酸锰(100g／L)溶液，在60．70℃水浴中加热2分钟，如紫红色褪去，示有草酸根离子。     

直接显色分光光度法测定水中硫化物

本文采用在碱性条件下加入乙酸锌溶液形成硫化锌沉淀的形式配制硫化物标准溶液,可增加硫化物标准溶液的稳定性。直接显色分光光度法测定水中硫化物方法是在常温、负压、低酸度下进行,该方法具有简便、快速、回收率高和操作简单等优点。相对标准偏差小于5．0％,相关系数为0．9991,加标回收率为84．5％～98．0％,是目前测定水中硫化物较为理想的方法。     

EDTA滴定法测定萤石中的CaF2

介绍一个快速测定萤石中CaF2的方法。试样中的碳酸盐经10％HAC选择溶解后，残渣用HNO3-HClO4分解，冒HClO4烟除氟。在pH5～6条件下，用六次甲基四胺-铜试剂进行沉淀分离，钙在pHl2．5用EDTA滴定。     

亚铁化合物水溶液的稳定方法Kitta，Akito 等 （ Sana K.K.jaoan）

该方法包括，向亚铁化合物水溶液中加0．01-1wt．％的桔酸。该溶液特别适用于脱色剂、植物活化剂、水处理剂。在曝露于大气或高温下有良好的稳定性，并可防止在暂时碱性条件下出现氢氧化铁沉淀。     

化妆品中防腐剂苯甲酸及其盐类和酯类的高效液相色谱法测定

建立化妆品中7种苯甲酸及其酯类化合物的HPLC～PAD检测方法，采用PAD检测器确定了7种化合物的最大吸收波长为230nm，以乙酸铵溶液（pH=4．5）-乙腈作为流动相进行梯度洗脱。7种化合物线性相关系数均〉0．999，方法的检出限％30mg／kg，精密度（RSD）在0．31％～7．37％之间，加标回收率在93．5％～132．2％。该方法简单、快速，精密度高，可用于化妆品中苯甲酸及其盐类和酯类化合物的检测。     

黄原酸钾含量的示波滴定

报道了用示波滴定法测定黄原酸钾含量 ,在 p H5～ 6的 HAc- Na Ac缓冲底液中 ,加入四苯硼钠 ( Na- TPB)沉淀 K+ ,过量的 Na- TPB用氯化四乙基铵标准溶液滴定 ,滴至 Na- TPB示波图切口消失为终点 ,终点直观敏锐 ,方法快速简便 ,准确度、精密度均高。标准加入回收率在 99.8%～1 0 0 .2 % ,RSD<0 .2 %     

TiO_2对尖晶石烧结性能的影响

尖晶石由于其优良的抗剥落和抗渣性能而广泛应用于盛钢桶耐火材料中，但由于尖晶石难烧结而影响其优点的发挥。日本一研究机构采取了加入TiO2细粉技术。试验发现，在10μm尖晶石细粉中加入0．2％～2．0％的TiO2，在1200℃下，TiO2的加入量对尖晶石的相对密度无影响；在1300℃以上时，尖晶石的相对密度随TiO2的加入量增加而提高；如在1500℃下，TiO2分别加入0．5％、1．0％、和1．5％时，其相对密度分别为72％、83％和94％，而不加入TiO2时，才为56％。TiO2加入量超过1．5％后，对尖晶石相对密度无多大影响。TiO_2对尖晶石烧结性能的…     

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。