海水中无机成分标准样品的定值和不确定度评估

按国家标准《GB/T 15000.3—2008标准样品工作导则(3)》评估了海水中无机成分标准样品。分别从标样的定值、均匀性、长期和短期稳定性等方面论述了不确定度的来源和评定方法,同时介绍了各种因素产生的不确定度以及总合成不确定度的计算方法。     

水泥及原材料中游离SiO2的化学分析方法

0引言 目前,游离SiO2的测定方法只有GB/T5762《石灰石化学分析方法》标准的附录中列出,这个方法只是适用于石灰石中游离SiO2的测定,因为石灰石中游离SiO2的含量较低,所列的方法具有局限性。对于游离SiO2含量较高的硅质校正原料,此结果只是一个参考值,准确度较差。     

焦炭中磷含量的测定

磷是焦炭中的有害元素之一。主要比较了检测焦炭中磷含量的三个标准:GB/T216-2003《煤中磷的测定方法》、GB/T1574-2007《煤灰成分分析方法》、和SN/T1083.2-2002《焦炭中磷含量的测定》。     

干灰化消解-原子荧光光谱法测定有机肥中总砷含量的研究

分析了GB/T 23349—2009和NY/T 1978—2010监测有机肥、生物有机肥中总砷含量所存在的缺陷,并根据所监测样品成分特点和原子荧光光度计检测砷元素的先进性,探讨研究了干灰化消解-原子荧光光谱法检测的方法。试验结果表明:砷含量在0.0~10.0μg/L范围内,干灰化消解-原子荧光光谱法线性关系良好,相关系数r=0.999 9,检出限为0.11μg/L,相对标准偏差(RSD)≤2.48%,加标回收率为92.0%~103.0%,可以满足大批量样品的日常监测要求。     

《建材用石灰石、生石灰和熟石灰化学分析方法》标准修订介绍

GB/T 5762-2000《建材用石灰石化学分析方法》标准的修订，根据采用国际标准和先进国家标准的要求，参考了ASTM C25-06a《石灰石、生石灰和熟石灰化学分析的标准试验方法》、BS 6463-102-2001《生石灰、熟石灰和天然碳酸钙的化学分析方法》和JIS M 8850-1994《石灰石化学分析方法》，并结合了我国建材用石灰石、生石灰和熟石灰的品质指标要求。     

离子膜法烧碱中碳酸钠含量的测定

应用GB/T 4348.1—2000《工业用氢氧化钠中氢氧化钠和碳酸钠含量的测定》和GB/T 7698—2003《工业用氢氧化钠碳酸盐含量的测定滴定法》两种标准方法测定碳酸钠含量,结果表明:黑龙江昊华化工有限责任公司"双三十项目"中30万t/a离子膜法烧碱装置开车样品中的碳酸钠含量达到了高纯液体氢氧化钠HL-Ⅱ型一等品指标,即碳酸钠质量分数≤0.06%。     

GC-MS法测定塑胶跑道材料中游离TDI的研究

建立了超声萃取结合气相色谱-质谱(GC-MS)联用的方法检测聚氨酯塑胶跑道材料中游离甲苯二异氰酸酯(TDI)的含量,并对新建操场的材料质量进行了评价。结果表明,塑胶跑道材料中游离的TDI均为2,4-TDI,相对标准偏差不超过2%,样品的加标回收率在89.85%~95.95%之间,说明该方法可以用于检测塑胶跑道材料中游离的TDI。对本实验所采集的样品的检测结果显示,TDI的含量没有超过GB/T 14833—2011《合成材料跑道面层》中规定的0.2 g/kg的标准。     

利用氟电极测定玻璃纤维中的氟含量

介绍了利用电极电位法测定玻璃纤维中氟含量的原理、试剂和方法。从测定数据的平行性和准确度等方面和标准样品给定值进行了对比,证明此方法完全可以应用于玻璃纤维的氟含量测定中。电极电位法和GB/T 1549-94《钠钙硅铝硼玻璃化学分析方法》中采用的比色法相比,分析步骤少、操作简单、干扰因素少、且容易克服。     

超高效液相色谱法测定稳定性肥料中双氰胺含量的不确定度评定

根据行业标准《肥料增效剂双氰胺含量的测定》(NY/T 2877—2015),采用超高效液相色谱法测定稳定性肥料中双氰胺的含量,对测定过程中的不确定度来源进行了分析,主要为标准溶液配制、标准曲线拟合、样品制备、样品测量重复性等4个方面。按《测定不确定度评定与表示》(JJF 1059.1—2012)的规定进行不确定度计算,双氰胺含量的测量不确定度来源主要为标准溶液配制与标准曲线拟合。稳定性肥料中双氰胺的合成标准不确定度为0.002 4%,扩展不确定度为0.005%,测定结果为0.168%±0.005%(k=2)。     

电子探针波谱法在碳酸盐矿物鉴定中的应用

方解石和白云石两种碳酸盐矿物在显微镜下很难区分,主要是通过岩石标本加稀盐酸是否剧烈气泡加以区别。为了准确鉴定大理岩中碳酸盐矿物组分,利用电子探针波谱技术对15件样品进行微区化学成分分析,并通过所测样品主量化学成分含量推测矿物名称;12件样品化学成分结果统计显示:主量成分CaO为56.07%~59.70%;次要成分含量:Cr_2O_3为0.00%~0.08%、FeO为0.00%~0.16%、Na_2O为0.00%~0.02%、Al_2O_3为0.00%~0.09%、MgO为0.52%~0.81%、SiO_2为0.00%~0.04%、MnO为0.00%~0.05%;化学成分与方解石组分相当,推测所测样品为方解石;3件样品化学成分结果统计显示:主量成分CaO为31.25%~31.82%、MgO为20.97%~21.31%;次要成分含量:Cr_2O_3为0.00%~0.05%、FeO为0.32%~1.17%、Na_2O为0.01%~0.08%、K_2O为0.01%~0.02%、SiO_2为0.00%~0.09%、MnO为0.01%~0.04%;化学成分与白云石组分相当,推测所测样品为白云石。     

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。