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1.
研究了以氯乙酸为起始原料经三次氯化合成三氯乙酰氯的新方法。氯气与熔融状态的氯乙酸接触反应制备一氯化料,一氯化料与一氯化硫、氯气加热反应制备二氯化料,在催化剂条件下二氯化料与氯气进行加热反应,精馏后制得三氯乙酰氯。该工艺的最佳条件为:一次氯化温度和时间分别为:105~135℃,15~20 h;二次氯化温度和时间分别为:90~115℃,20~25 h;三次氯化温度100~125℃。最终产品的总收率达到94.5%以上,含量达到99.0%。  相似文献   

2.
以五水合四氯化锡和碳酸氢铵为原料,用气-固相反应制备了纳米二氧化锡,并用X-射线衍射(XRD)和透射电镜(TEM)对粉末进行了表征。气-固相反应制备纳米二氧化锡的最佳工艺为:五水合四氯化锡和碳酸氢铵的物质的量比为1:8,焙烧温度240℃,焙烧时间24h,热处理温度500℃,热处理时间0.5h。在最佳工艺条件下,二氧化锡的粒径约为5~10nm,产率达84.3%。  相似文献   

3.
真空法合成甲基硫醇锡研究   总被引:1,自引:1,他引:0  
研究了以巯基乙酸异辛酯和甲基氯化锡为原料,在真空下直接合成甲基硫醇锡的工艺.该法操作简单、成本低,该工艺分3个阶段分别控制压强、温度和时间,其最佳反应条件为,第一阶段2.667kPa,70℃反应2h;第二阶段1.333kPa,80℃反应2h;第三阶段0.667kPa,80℃反应1h。合成的产品质量稳定,并能有效降低污染物的排放量,甲基氯化锡的转化率在99%以上。  相似文献   

4.
采用氯酸钠氧化法以200μm左右粒度的硫铁矿烧渣为原料,硫酸和盐酸作浸取液,制备聚合氯化硫酸铁铝(PAFCS)絮凝剂,通过正交试验优化了最佳工艺条件:浸取温度为120℃,浸取时间为1.5h,酸与渣质量比为3.0;聚合温度为110℃,聚合时间为2.0h。猪场废水絮凝试验表明,PAFCS的絮凝除杂效果远好于聚合氯化铝(PAC),而接近于聚合硫酸铁(PFS)。该方法成本较低,有利于环境保护。  相似文献   

5.
蔡亮  程原 《化工中间体》2008,4(12):29-32
本实验采用Raney—Ni作为催化剂,研究了由对羟基苯腈合成对羟基苯甲脒的工艺条件。通过实验考察了时间(5h~11h)、压力(0.3MPa~0.8MPa)、温度(50℃~85℃)等因素对产率的影响。得到了适宜的工艺条件为:反应压力0.7MPa、反应时间9h、搅拌速率600r·min^-1、反应温度70℃。  相似文献   

6.
张瑞芹 《河北化工》2008,31(4):43-44
以工业硫磺和液氯为主要原料,直接制备二氯化硫.确定了合成反应最佳工艺条件:起始反应温度为100~110℃,氯气通入时间(即反应时间)为6 h,通氯气量为75 L/h,精制蒸馏温度为60~64℃,稳定剂三氯化磷用量为0.1%~0.3%.在此工艺条件下制备的二氯化硫收率可达82%以上.  相似文献   

7.
以工业硫磺和液氯为主要原料,一步法直接制备二氯化硫。确定了合成反应最佳工艺条件:起始反应温度100~110℃,氯气通入时间(即反应时间)6h,通氯气量75L/h,精制蒸馏温度60~65℃,稳定剂三氯化磷用量0.1%~0.3%。在此工艺条件下制备的二氯化硫收率可达80%以上。  相似文献   

8.
钛酸锶粉体合成新方法研究   总被引:6,自引:0,他引:6  
以四氯化钛和氯化锶为原料,碳酸铵和氨水作沉淀剂化学共沉淀法合成钛酸锶粉体,研究了工艺条件对产品纯度和锶钛比的影响,最佳反应条件为:氯化锶与四氯化钛摩尔比为1.02,碳酸铵与氯化锶摩尔比为1.40,反应温度为室温,反应时间4h,pH=10,煅烧温度900℃,煅烧时间4h,所得产品经化学,红外光谱,电镜,X-射线衍射和原子发射光谱分析,分析结果显示:产品纯度高,粒径小,锶钛化合适。  相似文献   

9.
采用氯气对Hp沸石载体进行改性,利用共浸渍法制备出Ni—W/CI2-Hβ多功能催化剂,并用BET和IR技术测定各种样品的物化性质。系统考察氯化条件及反应温度对催化剂催化性能的影响。结果表明,当氯化温度为600℃,氯化时间为6h,合成出的催化剂具有降烯烃脱硫性能。且反应温度为160℃时,催化剂的活性最佳,汽油烯烃体积分数降低20.5个百分点,硫的脱除率为35.0%,研究法辛烷值RON损失0.8个单位,汽油收率大于98.0%。BET和IR谱技术测定结果显示,氯化改性改善了载体表面性质。  相似文献   

10.
一步水热法是将氧氯化锆和氨水按比例混和后,直接加入高压反应釜中进行水热反应的工艺。由于不需要经过前驱物的制备流程,简化了工艺,由于原料中引入的NH4^4及C1^-在水热反应中起到了矿化剂的作用,与传统工艺比较,产物的晶化程度提高。通过单因素优化实验,较佳的工艺条件为:氧氯化锆的浓度为0.5~1mol/L,氨水质量分数13%~25%,反应混合物的pH为9~10,水热温度180~200℃,水热压力1.0~1.5MPa,保温2~3h,产品的平均粒度约10nm。  相似文献   

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12.
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.  相似文献   

13.
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.  相似文献   

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15.
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.  相似文献   

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18.
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.  相似文献   

19.
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.  相似文献   

20.
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。  相似文献   

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