固定床反应器内气流均布技术的初步研究

本文作者对侧向进、出口的固定床反应器的气流均布技术进行了实验研究。在φ0.4米、0.535×0.535米以及1.32×1.32米的装置中,通过改变支承板与进、出口管中心的垂直距离 H 以及附加填料(瓷球)层高度、瓷球直径等参数来考察它们对气流均布的影响,提出了改进气流分布的技术措施。     

快速流化床反应器用于丁烯氧化脱氢制取丁二烯的宏观动力学研究

本工作是在内径为26mm 的快速流化床反应器中,以丁烯氧化脱氢制取丁二烯的过程为内容,在330℃～370℃的温度范围内进行了宏观动力学研究。根据快速流化床的流动特性,以气相为基础,对其实验结果采用了拟均相模型处理,求得总反应转化率表达式 X_A=1-exp(-kτ),其中反应速度常数 K=1.123×10~4exp[-42990.70/RT],总的反应表观活化能 E=4.299×10~4(J/mol).同时还计算了主付反应的下列参数:k_1=1.133×10~4exp[-4.339×10~4/RT]k_2=2.511×10~2exp[-3.739×10~4/RT]E_1=4.339×10~4 J/molE_2=3.739×10~4 J/mol并以下列方程组:k_1,k_2x_A=1-exp[-(k_1+k_2)ετ]y_Q=(k_1/k_1+k_2)·X_A来予测反应过程中丁烯的转化率及丁二烯的收率情况,用此方法计算的结果与实验值之相对误差均在±8%范围以内。     

正丁基锂_丁二烯_二氧六环阴离子聚合体系的动力学研究

以二氧六环为溶剂,以正丁基锂为引发剂,在充氮条件下,利用膨胀计进行了丁二烯聚合增长反应动力学研究。结果表明,增长反应对单体浓度和活性种浓度的反应级数皆为一级关系;活化能为34.54kJ/mol,频率因子为2.44×10~7L·mol~(-1)·min~(-1);并求出生成1,4-和1,2-结构含量的分速度常数分别为k_3=7.70×10~7 e~(-9900/RT)L·mol~(-1)·min~(-1),k_4=9.44×10~6 e~(-7800/RT)L·mol~(-1)·min~(-1);同时求出在二氧六环溶剂中 1,2-结构含量与温度关系的经验公式为 a=85.39-0.178 t,指数关系式为a=0.387 e~(450/RT)。     

合成己二腈宏观反应动力学的研究

本文对于以磷酸为催化剂,用熔融(液相)已二酸与气相氨作用生成己二腈的反应过程,研究了中和与脱水反应的宏观动力学。实验考察了温度、时间和催化剂浓度等对反应的影响,结果表明中和反应是受传质和化学反应动力学共同影响的快速反应。在 C_B≥3.5%时,反应对己二酸浓度为一级,在 C_B<3.5%时,属于动力学控制的二级反应,其速率常数为:k_1=3.31×10~4exp[-(13.8-158C_P)×10~3/RT]k_2=3.07×10~4exp[-(23.4-420C_P)×10~3/RT]同时提出了总脱水为一级反应,其速率常数为:k=1.03×10~8exp{-[23.6+2.07exp(-644C_P)]×10~3/RT}     

分段进气环流反应器传质性能及在葡萄糖氧化中的应用

在多级环流反应器的基础上,发展了一种新型分段进气、多级环流反应器(MS-MSALR)。在气流量为0.2～0.6m3/h的条件下,研究了MS-MSALR中体积传质系数、葡萄糖氧化反应速率随气流量的变化规律,并与多级环流反应器进行了比较。多级环流反应器的体积传质系数随气流量的增加而增大,葡萄糖氧化反应速率随气流量的增加而增加。MS-MSALR的体积传质系数呈抛物线状分布,最大值约为多级环流反应器的2.4倍;反应速率在Q2/Q1较小时取得最大值,并保持不变。     

我国页岩气资源潜力首次评价

<正>近日,我国资源部首次发布《我国页岩气资源潜力调查评价和优选》成果。经初步评价,我国陆域页岩气地质资源潜力为134.42×1012 m3,可采资源潜力25.08×1012 m3(不含青藏区)。其中,已获工业气流或有页岩气发现的评价单元,面积约88×107 m2,地质资源93.01×1012 m3,可采资源15.95×1012 m3,是目前页     

双磷酸酯表面活性剂的合成与性能

以三氯氧磷、二元醇(酚)、正十二醇为原料,合成了4种双十二烷基双磷酸酯(HDP,DGDP,BDP,PDP)。产物经无水乙醇重结晶提纯后,通过IR、1HNMR、质谱和电位滴定进行了结构表征。25℃时,它们的电离常数分别为:2.76×10-5mol/L(HDP),3.940×10-4mol/L(DGDP),1.595×10-4mol/L(BDP),4.255×10-3mol/L(PDP)。20℃时,它们的临界胶束浓度分别为:3.5×10-4mol/L(HDP),9.0×10-4mol/L(DGDP),1.1×10-3mol/L(BDP),1.3×10-3mol/L(PDP);在临界胶束浓度处的表面张力分别为:30.38 mN/m(HDP),34.49 mN/m(DGDP),35.31 mN/m(BDP),36.14 mN/m(PDP)。差热分析表明,4种产物的分解温度分别为:231℃(BDP),251℃(HDP),227℃(PDP),249℃(DGDP);初熔温度分别为:87℃(BDP),80℃(HDP),97℃(PDP),72℃(DGDP)。     

一段转化炉(F1201)

(一)概述炉为一种门箱式侧壁烧嘴上烟道的炉,炉子外型尺寸24125×8350×24550m/m(长×宽×高),内装有φ102/φ143m/m炉290根总长11305m/m(有效长10502m/m)触煤装置24.9M~3(24.655吨),侧壁烧嘴480个,烧嘴燃烧放热1.119亿大卡/时,辐射段炉     

PTFE超细粉的研制与应用

本文叙述了用PTFE废弃边角屑料经辐射裂解,超微气流粉碎制备PTFE超细粉的工艺过程与应用范围。PTFE超细粉的分子量为6.9×10~4～7.9×10~4,粒度达1～20μm。     

极板间距对电生物体系降解甲基橙废水的影响

采用1、2、3 cm极板间距的3个厌氧单室电生物反应器对甲基橙废水中污染物进行降解实验。结果表明,1、2、3 cm的极板间距甲基橙脱色速率常数k_1(1.253 h~(-1))k_2(1.135 h~(-1))k_3(0.801 h~(-1)),COD去除率2 cm极板间距的反应器(54.2%)比1 cm(39.2%)、3 cm(43.8%)高。1 cm极板间距的反应器阴极电位降低最快且最低,而2 cm极板间距的反应器中电流密度最大,混合液ORP电位最低。3个电生物体系中2 cm极板间距的反应器内阻最小,生物膜活性最高。     

Sapindaceae,cyanolipids, and bugs

Scentless plant bugs (Heteroptera: Rhopalidae) are so named because adults of the Serinethinae have vestigial metathoracic scent glands. Serinethines are seed predators of Sapindales, especially Sapindaceae that produce toxic cyanolipids. In two serinethine species whose ranges extend into the southern United States,Jadera haematoloma andJ. sanguinolenta, sequestration of host cyanolipids as glucosides renders these gregarious, aposematic insects unpalatable to a variety of predators. The blood glucoside profile and cyanogenesis ofJadera varies depending on the cyanolipid chemistry of hosts, and adults and larvae fed golden rain tree seeds (Koelreuteria paniculata) excrete the volatile lactone, 4-methyl-2(5H)-furanone, to which they are attracted.Jadera fed balloon vine seeds (Cardiospermum spp.) do not excrete the attractive lactone. Loss of the usual heteropteran defensive glands in serinethines may have coevolved with host specificity on toxic plants, and the orientation ofJadera to a volatile excretory product could be an adaptive response to save time.Mention of a commercial product does not consititute an endorsement by the USDA.     

2008～2009年世界塑料工业进展

收集了2008年7月～2009年6月世界塑料工业的相关资料,介绍了2008～2009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、环氧树脂、不饱和聚酯树脂)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。     

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.     

Many Drugs of Abuse May Be Acutely Transformed to Dopamine,Norepinephrine and Epinephrine In Vivo

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.     

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.