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1.
500t/a中试规模制备小颗粒4A沸石的研究   总被引:1,自引:0,他引:1  
在500 t/a的中试设备上,以全化学合成法进行了小颗粒4A沸石合成的中试放大实验。采用正交实验方法考察了原料配比A〔n(SiO2)/n(Al2O3)〕、B〔n(Na2O)/n(Al2O3)〕、C〔n(H2O)/n(Al2O3)〕及晶化时间D(t)对产品性能的影响。通过方差分析,确定出其最佳工艺条件为:n(SiO2)/n(Al2O3)=1.8~1.9,n(Na2O)/n(Al2O3)=3.2~3.4,n(H2O)/n(Al2O3)=80~100,t=20 min。工艺验证实验结果表明,该条件下的中试产品钙交换能力≥295 mg CaCO3/g干基,符合QB1767—2003的一级品标准。  相似文献   

2.
N-甲基吡咯烷酮生产工艺影响因素分析   总被引:1,自引:0,他引:1  
以γ-丁内酯(GBL)、甲胺为原料制备N-甲基吡咯烷酮(NMP),考察了影响反应的工艺条件,实践表明,n(CH3NH3):n(GBL)为1.6~1.8,n(H2O):n(GBL)为3.6~4.0,反应温度为275~285℃,反应时间为为2.0 h,反应压力为6.0 MPa,GBL转化率≥99%,NMP选择性≥96%.  相似文献   

3.
苯基二氯化膦的合成工艺研究   总被引:1,自引:0,他引:1  
熊明金  王国栋 《云南化工》2005,32(3):16-19,22
以PCl3和苯为原料,在无水AlCl3催化作用下合成DCPP,研究了各反应条件的影响。采用NaCl配合剂除去催化剂AlCl3。较佳的工艺条件是:n(C6H6)∶n(AlCl3)∶n(PCl3)=1∶1∶2,反应时间:8h,反应温度75℃~76℃,收率达到75%。  相似文献   

4.
不同硅铝比ZSM-22分子筛的合成   总被引:1,自引:0,他引:1  
吴卓  谭涓  刘靖  尹大元 《工业催化》2010,18(1):26-30
采用静态水热合成法,以氢氧化钾为碱源,硅溶胶为硅源,1,6-己二胺为模板剂,考察了晶化温度[(423~443)K]、晶化时间[(12~72)h]和原料配比对合成ZSM-22分子筛的影响,优化了合成条件。结果表明,最佳合成条件为:晶化温度433 K、晶化时间48 h、n(Al2O3)∶n(SiO2)∶n(K2O)∶n(DAH)∶n(H2O)=0.11∶10∶1.3∶3.0∶400。在此基础上,通过碱度的调变,合成了较纯n(Al2O3)∶n(SiO2)=40~130的ZSM-22分子筛。  相似文献   

5.
载体强酸催化合成柠檬醛二乙缩醛   总被引:4,自引:0,他引:4  
研究了以复合载体强酸 (Ph SO3H/Na2 SO4·CaSO4)催化合成柠檬醛二乙缩醛的新方法 ,得到柠檬醛直接与无水乙醇一步反应的最佳条件 :投料比n(柠檬醛 )∶n(无水乙醇 )∶n(苯磺酸 ) =1∶ (4~ 5 )∶(0 .0 2 5~ 0 .0 0 3 0 ) ,控制反应温度 80℃ ,反应时间 1 .5h。该优化条件下 ,合成收率为 93 %~ 94% ,粗成品纯度可达 96 %  相似文献   

6.
木质素阳离子乳化剂的制备及其表面活性   总被引:10,自引:1,他引:10  
刘祖广  王迪珍 《精细化工》2004,21(8):567-570
先用环氧氯丙烷和三乙胺反应制备环氧丙基三乙基氯化铵中间体,再与木质素反应制得木质素季铵盐。中间体制备条件是温度45~50℃,时间3h,n(三乙胺)/n(环氧氯丙烷)=1~1 1。木质素季铵盐制备条件为温度50~55℃,时间2h,n(木质素)/n(中间体)=0 6~0 8,pH>10 5。产物的表面活性测定表明,不同接枝率的木质素季铵盐降低水溶液表面张力的能力相差不大,最低表面张力约为40mN/m。  相似文献   

7.
孙曰圣  张小林  杨期勇 《精细化工》2003,20(7):409-411,421
研究了三甲胺盐酸盐与环氧氯丙烷在乙醇水溶液中催化反应生成氯化3 氯 2 羟丙基三甲铵(CHPTMA),再经氰化反应生成氯化3 氰 2 羟丙基三甲铵(氯化肉碱腈)的工艺。通过正交实验得到了催化反应最佳工艺条件:反应液pH=8~9、反应温度35℃、n(环氧氯丙烷)/n(三甲胺盐酸盐)=0 95、反应时间1h,在此实验条件下进行合成,产率93%。氰化反应最佳工艺条件:反应温度40~45℃、反应时间1 5h、n(氰化钠)/n(CHPTMA)=1 05,在此条件下,产率为78 8%。  相似文献   

8.
三相相转移催化合成对硝基苯甲醚的研究   总被引:3,自引:0,他引:3  
合成制备了聚苯乙烯支载聚乙二醇 ,并以之作为三相相转移催化剂用于对硝基氯苯合成对硝基苯甲醚 ,考察了催化剂、NaOH、CH3OH等的用量对反应转化率的影响 ,得到了适宜的合成工艺条件为 :n(PCNB)∶n(CH3OH)∶n(NaOH)∶n(PTC) =1∶3∶3∶(0 0 3~ 0 0 5) ,反应温度约 78~ 80℃ ,反应时间 9~ 1 0h。在该条件下 ,对硝基氯苯转化率大于 99 5 % ,收率大于 95 % ,产品经气相色谱检测纯度达 99 7% ,聚苯乙烯支载聚乙二醇催化剂可重复使用 5次以上 ,反应母液经除盐后 ,配碱套用对反应无不良影响  相似文献   

9.
间硝基苯甲醛的合成工艺研究   总被引:1,自引:0,他引:1  
以间硝基甲苯为原料,以AIBN(偶氮二异丁腈)为催化剂合成间硝基苯甲醛。在n(间硝基甲苯)∶n(氯溴酸)∶n(双氧水)=1∶3∶3,溴化温度65~75℃,溴化时间8~9h,氧化水解时间在8h的优化条件下,产品收率30.4%,纯度99.2%。  相似文献   

10.
以丙酮氰醇(ACH)、水合肼、Cl2、甲醇(CH3OH)和HCl为原料,经缩合、氧化、Pinner反应、水解反应制备2,2’-偶氮二异丁酸二甲酯,对反应条件进行了优化。确定反应的最佳工艺条件为n(ACH)∶n(水合肼)∶n(四甲基溴化铵)=1∶0.53∶0.0052、n(偶氮二异丁腈肼)∶n(Cl2)∶n(HCl)∶n(CH3OH)=1∶1.1∶0.8∶2.6、缩合反应温度25~30℃、反应2 h、氰醇化反应温度10~15℃、反应24 h,产品纯度在98%以上,总收率大于90%。  相似文献   

11.
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   

12.
It is well established that a wide range of drugs of abuse acutely boost the signaling of the sympathetic nervous system and the hypothalamic–pituitary–adrenal (HPA) axis, where norepinephrine and epinephrine are major output molecules. This stimulatory effect is accompanied by such symptoms as elevated heart rate and blood pressure, more rapid breathing, increased body temperature and sweating, and pupillary dilation, as well as the intoxicating or euphoric subjective properties of the drug. While many drugs of abuse are thought to achieve their intoxicating effects by modulating the monoaminergic neurotransmitter systems (i.e., serotonin, norepinephrine, dopamine) by binding to these receptors or otherwise affecting their synaptic signaling, this paper puts forth the hypothesis that many of these drugs are actually acutely converted to catecholamines (dopamine, norepinephrine, epinephrine) in vivo, in addition to transformation to their known metabolites. In this manner, a range of stimulants, opioids, and psychedelics (as well as alcohol) may partially achieve their intoxicating properties, as well as side effects, due to this putative transformation to catecholamines. If this hypothesis is correct, it would alter our understanding of the basic biosynthetic pathways for generating these important signaling molecules, while also modifying our view of the neural substrates underlying substance abuse and dependence, including psychological stress-induced relapse. Importantly, there is a direct way to test the overarching hypothesis: administer (either centrally or peripherally) stable isotope versions of these drugs to model organisms such as rodents (or even to humans) and then use liquid chromatography-mass spectrometry to determine if the labeled drug is converted to labeled catecholamines in brain, blood plasma, or urine samples.  相似文献   

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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   

18.
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   

19.
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   

20.
Inorganic/organic hybrid materials have considerable promise and are beginning to become a major area of research for many coating usages, including abrasion and corrosion resistance. Our primary approach is to prepare the inorganic phase in situ within the film formation process of the organic phase. The inorganic phase is introduced via sol-gel chemistry into a thermosetting organic phase. By this method, the size, periodicity, spatial positioning, and density of the inorganic phase can be controlled. An important aspect of the inorganic/organic hybrid materials is the coupling agent. The initial task of the coupling agent is to provide uniform mixing of the oligomeric organic phase with the sol-gel precursors, which are otherwise immiscible. UV-curable inorganic/organic hybrid systems have the advantages of a rapid cure and the ability to be used on heat sensitive substrates such as molded plastics. Also, it is possible to have better control of the growth of the inorganic phase using UV curing. It is our ultimate goal to completely separate the curing of inorganic and organic phases to gain complete control over the morphology, and hence optimization of “all” the coating properties. Thus far, it has been found that concomitant UV curing of the inorganic and organic phases using titanium sol-gel precursors afforded nanocomposite coatings which completely block the substrate from UV light while maintaining a transparent to visible light. Also, it has been found that the morphology of the inorganic phase is highly dependent on the concentration and reactivity of the coupling agent. Presented at the 82nd Annual Meeting of the Federation of Societies for Coatings Technology, October 27–29, 2004, in Chicago, IL.  相似文献   

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