ICP-MS法测定海南槟榔园土壤中的重金属元素

海南槟榔园土壤中重金属元素的含量对槟榔果实的质量影响至关重要。采用HCl+HNO_3+HF+HClO_4对样品完全消解后,通过ICP-MS法测定槟榔园土壤中的重金属元素Cu、Pb、Zn、Cd、Cr。该方法以Rh做内标,并优化仪器条件,有效克服了基体效应及质谱干扰的影响。结果表明:方法中各元素的检出限较低,分别是Cd 0.02μg/g、Cu 0.1μg/g、Pb 0.2μg/g、Cr1.0μg/g、Zn1.0μg/g;各元素的精密度在0.07~0.16,均小于0.17,准确度小于0.10,并用GBW07401~404(GSS–1~GSS–4)对方法验证,结果满意。     

蒙药嘎日迪五味丸中微量元素的初级形态分析

采用电感耦合等离子发射光谱法(ICP-AES)对嘎日迪五味丸中Zn、Fe、Mn、Cu、Ni、Se等元素进行分析。结果表明:元素Fe含量最高(5 926.7μg/g),元素Ni(45.01μg/g)含量最低,而其中元素Ni(75.46%)总提取率最高,元素Cu(34.28%)总提取率最低。该研究结果为进一步探讨嘎日迪五味丸中微量元素与药效之间的关系提供参考。     

ICP-MS法测定玩具材料中硼酸和硼酸盐含量及风险评估

建立了电感耦合等离子体质谱法(ICP-MS)测定玩具材料中硼酸和硼酸盐含量的方法。样品前处理以10%(v/v)乙醇作为萃取剂,在(37±2)℃水浴中连续振荡4 h,振荡频率为120 r/min。仪器工作条件:在KED模式下,以⁽¹¹⁾B作为分析同位素,铍为内标元素,驻留时间为0.05 s。硼元素的线性范围为2～1 000μg/L,线性相关系数(r(11)B作为分析同位素,铍为内标元素,驻留时间为0.05 s。硼元素的线性范围为2～1 000μg/L,线性相关系数(r²)为0.999 52,背景等效浓度(BEC)为4.19μg/L,硼酸的方法检出限为1.83 mg/kg,硼酸盐的方法检出限为2.83 mg/kg,加标回收率为96.0%～102.4%,相对标准偏差(RSD,n=6)为1.5%～4.3%。该方法简便、快速,具有较高的准确度和良好的精密度,适用于玩具材料中硼酸和硼酸盐的检测要求。添加硼酸和硼酸盐的风险主要存在于软性玩具材料中。     

ICP-MS法快速检测食品添加剂中的砷

样品经硝酸消解完全后,由电感耦合等离子体质谱仪测定,以元素特定质量数(质荷比,m/z)定性,以待测元素质谱信号与内标元素质谱信号的强度比与待测元素的浓度成正比进行定量分析。在1~500μg/L范围内标准曲线的相关系数大于0.999,回收率为91.0%~105%,定量限(LOQ)为0.098μg/L,检出限(LOD)为0.030μg/L。该方法方便,简单,缩短了检测时间,适合批量快速检测食品添加剂中的砷。     

用于钠离子电池的过期复方阿胶浆衍生的氮/硫共掺杂硬碳微球负极

通过水热碳化成球及后续热解反应从过期复方阿胶浆中提取得到了硬碳材料,并研究了其微观形貌、元素组成、结构和储钠性能。结果表明,所得到的碳材料呈现平均直径约为4.3μm的光滑微球形貌,氮/硫元素均匀地分布在碳微球中且石墨化程度较低;在0.5和1.0 A/g各循环500圈时,碳微球负极的可逆放电比容量分别稳定在225和180 m Ah/g,即使在高达2.0 A/g的电流密度循环1 000圈时,放电比容量仍维持在108 m Ah/g,表现了良好的高倍率循环储钠稳定性。无疑,该结果有助于推进过期废药的循环经济模式和绿色能源的发展。     

电感耦合等离子体质谱法测定饮用水中17种元素

本文以Li6、Sc、Ge、In、Tb、Bi混合内标为校正系统,研究建立了电感耦合等离子体质谱法在碰撞池技术模式下同时测定饮用水中17种元素的方法。实验条件下,17种元素的线性相关系数均不低于0.9996,方法检出限为0.008μg/L~0.71μg/L,平行测定的RSD〈7%,饮用水样品的加标回收率为93.10%~104.7%。该方法操作简单,检出限低,准确度高,精密度好,适用于多种元素快速检测。     

中量元素水溶肥料及其在番茄上的喷施效果

制备了中量元素水溶肥料,主要营养成分为钙和镁,具体技术指标为:Ca~(2+)+Mg~(2+)=105g/L,Ca/Mg(m/m)=1∶1。开展了番茄喷施中量元素水溶肥料肥效实验,结果表明:在常规施肥的基础上,喷施中量元素水溶肥料,与同期喷施等量清水和空白处理相比,单株结果数增加0.55个和0.78个,单果重增加6.09g和10.88g,亩均增产450.3kg和492.0kg,增幅为10.1%和11.2%。     

高纯硅微粉中多个杂质元素的质谱分析

建立电感耦合等离子体串联质谱(ICP-MS/MS)法在多元素分析中的应用.高纯硅微粉经氢氟酸+硝酸微波消解后直接采用ICP-MS/MS测定其中8个常见杂质元素(Na、Mg、Al、K、Ti、Fe、Cu、Zn).在MS/MS模式下,通过向碰撞反应池(CRC)中通入NH3/He,利用目标离子与NH3/He发生反应消除多原子离子质谱干扰,其中Na、Mg、Al、K、Zn采用NH3/He原位质量测定,Ti、Fe、Cu采用NH3/He质量转移测定,考察了NH3/He反应气流速待测元素分析结果的影响,优化并获得了最佳NH3/He反应气流速.选择Sc为内标元素校正样品传输、雾化效率以及信号强度变化时所产生的误差.8个待测元素的检出限为0.001~0.76μg/L,采用所建立的方法分析国家标准物质石英岩(GBW07835),测定结果与标准物质所提供的验证值基本一致,相对标准偏差(RSD)≤5.5%,表明方法具有准确性好和精密度高的特点,可用于高纯硅微粉中多个杂质元素的准确分析.     

叶面喷施黄腐酸对番茄生长和果实质量的影响

<正>为了研究叶面喷施黄腐酸对番茄生长、果实质量、产量的作用效果,分别在番茄定植后10、20、30天将黄腐酸(20mL)以浓度为0、0.8、1.1、1.6 g/L喷施于叶面,0.8 g/L处理的植物株高、鲜重、干重均显著增加,1.6 g/L处理则显著下降。在0.8 g/L和1.1 g/L处理中,P和Ca的元素含量均增加,其他元素多未发生变化。研究结果显示,在番茄的生产中叶面喷施浓度为0.8 g/L     

电感耦合等离子体质谱法测定水中元素全量的不确定度评定

本文对电感耦合等离子体质谱法测定水中元素全量的不确定度进行了评定。经评定,当钴、镍、铜、钼的浓度分别为29.8μg/L、30.6μg/L、29.2μg/L、27.0μg/L时,扩展不确定度分别为3.2μg/L、4.2μg/L、2.7μg/L、2.1μg/L。这4种元素检测结果的不确定度主要由元素校准曲线拟合和重复性的不确定度构成。     

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。