酸浸法除陶瓷粘土中铁杂质的实验研究

采用盐酸作酸浸剂对陶瓷粘土进行除铁实验,考察了盐酸浓度、反应温度、浸出时间、矿浆浓度等因素对陶瓷粘土除铁增白效果的影响,得出最佳方案:盐酸的质量分数为15％、反应温度为60℃、浸出时间为120min,矿浆浓度为15％.经除铁增白后,粘土中铁的质量分数由原来的0.96％降为0.49％.     

钾长石的除铁新工艺研究

以四川乐山钾长石矿为原料,采用正交实验法研究了酸浸反应温度、硫酸浓度和实验时间对除铁效果的影响,得出最优实验条件为:酸浸温度90℃,酸体积分数为40%,反应时间为2h.并对实验结果进行了分析;对酸浸除铁后粉末进行浮选除铁,得出最佳浮选助剂为油酸钠,矿石粉末为200目.     

酸浸除铁提纯硅片切割副产物工艺研究

本文研究了以酸作为浸取剂浸取除铁提纯硅片切割副产物的工艺过程.通过研究酸的浓度、液固比、反应温度、反应时间对除铁效率的影响,提出了较合适的提纯工艺参数.结果表明:当酸的浓度为3.0 mol/L、液固比为2∶1、反应温度60℃、反应时间50 min时有较好的除铁效果.在最佳实验条件下,除铁率达到98.15％.该工艺为后续提纯碳化硅提供技术保障.     

太阳能级多晶硅切割废料的酸洗除杂研究

为获得一种制备高纯硅的高纯原料,在分析太阳能级多晶硅切割废料(CLW)物性的基础上,详细研究了CLW的酸浸除杂,超声酸浸除杂,考察了盐酸浓度、酸浸时间、酸浸温度、酸浸液固比和搅拌对除杂效果的影响,并分析了超声酸洗过程动力学,得到的最适宜工艺条件为:w(盐酸)为19％,反应时间3 h,水浴温度为60aC,浸出液固比4:1...     

煤矸石酸浸液初步脱铁的试验研究

以煤矸石在最优水平组合下得到的酸浸反应液为研究对象,分析其组分含量,结果表明:100g煤矸石酸浸得到的反应液中Al2O3、Fe2O3质量分别为29.82g、1.13g,其中铁含量不能满足工业用硫酸铝一级品要求。因此,本研究取100g煤矸石在酸浸条件最优的水平组合下反应得到的滤液,以煤矸石作为除铁物料进行初步脱铁,系统研究了反应温度、反应时间和煤矸石加量对脱铁的影响,以溶液中Fe2O3的最终含量为指标来考察各因素对除铁效果的影响,确定工艺条件。研究结果表明:反应温度为100℃、反应时间为4h,煤矸石加量为100g时,除铁率达到82.7%,此时溶液的铁含量达到了工业用硫酸铝一级品要求。研究成果具有较好的应用前景。     

辽宁长石矿除铁工艺优化的研究

试验针对辽宁某地的长石的特点,首先用化学沉淀法确定长石中的铁含量,在参考已有的长石除铁方法的基础上,综合优化选择出合适的除铁工艺。本试验最终确定的除铁工艺为锤式破碎-球磨机细磨-酸浸-过滤-干燥-成品。采用正交试验的方法研究盐酸酸度、盐酸浸泡时间、盐酸浸泡温度对除铁效果的影响,最终确定20%的盐酸,在酸浸温度为94℃,酸浸时间为5h的条件下长石粉酸浸除铁的效果最好。对比长石除铁前后的X R D图可得,除铁之后长石中铁的峰值明显下降,二氧化硅的峰值由2900增加到17000,酸浸除铁效果显著。对比除铁前后的颜色可得,除铁之后长石的白度明显增加,长石质量明显提高。     

还原焙烧钛渣盐酸浸出过程的动力学

对钠化焙烧钒钛磁铁矿产生的新型焙烧钛渣,采用盐酸加压浸出方法提钛,根据反应前后物相变化,考察了酸浓度、液固比、反应温度、反应时间等对钛浸出率的影响. 结果表明,加压酸浸的最优条件为反应温度120℃,反应时间2 h,盐酸浓度30%(?),液固比8 mL/g. 该条件下,TiO2浸出率可达95%以上. 根据固体产物层内扩散控制模型的动力学方程和Arrhenius方程,利用焙烧渣在不同反应温度下的转化率与反应时间的关系得出焙烧渣在盐酸体系中常压分解动力学方程为1+2(1?x)?3(1?x)2/3?11.4e?31.2/(RT)t,反应的表观活化能为?31.2 kJ/(mol?K).     

高硅高铁粉煤灰制备SiO2的工艺研究

以碳酸钠为活化剂活化粉煤灰,考察原料配方、焙烧条件(温度、时间)、酸浸条件(用量、浓度)、溶胶一凝胶条件(初始浓度、温度)对SiO2产率的影响.结果表明:(1)当m粉煤灰∶m碳酸钠≥1∶1.8或焙烧温度超过850℃时,样品发生烧结无法从坩埚中取出,面致酸浸分解率和SiO2产率为零;(2)粉煤灰在没有助剂条件下进行高温活化,酸浸分解率为24.13％,无SiO2产品;(3)盐酸浓度和溶胶-凝胶液的初始浓度对SiO2的产率基本无影响;(4)温度是影响溶胶-凝胶的显著因素;(5)最佳工艺条件为∶m粉煤灰∶m碳酸钠=1∶1.2、焙烧温度800℃、焙烧时间2h;凝胶-凝胶水浴温度94℃,SiO2的产率可达85.35％.     

电解锰渣酸浸实验条件探究

以铜仁市某电解锰企业排放的电解锰渣为原料,通过X射线衍射及化学分析方法分析锰渣中主要物相及成分含量.实验中以盐酸作为酸解剂,考察盐酸浓度、固液比、反应时间、反应温度对锰渣分解率的影响,通过正交试验表明:盐酸浓度对分解率的影响最为显著,其次是反应固液比、反应温度,反应时间对锰渣分解率的影响最小,在最佳酸浸条件下测得锰的浸出率为95.89％,铁的浸出率为94.69％,钙的浸出率为63.38％,铝的浸出率为2.21％,NH4+-N浸出率96.34％.     

江西弋阳蛇纹石硫酸浸出过程工艺条件的优化研究

文章在常压、较低温度(<100℃)下,开展了江西弋阳蛇纹石硫酸浸出工艺条件的研究.以蛇纹石中氧化镁的浸出率为主要考察指标,通过单因素条件实验和正交实验,分别考察了蛇纹石酸浸反应温度、酸浸反应时间、硫酸溶液质量浓度、液固比等因素的变化对蛇纹石中氧化镁浸出率的影响,所得较佳的工艺条件为:酸浸反应温度95℃、酸浸反应时间5h...     

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.     

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。     

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.