DETA-PZ复合溶液吸收与解吸CO_2实验研究

以烯胺吸收剂DETA(二乙烯三胺)为主吸收剂与辅助吸收剂PZ(哌嗪)按物质的量配比20∶1～20∶6进行复配,通过一次循环吸收、解吸实验,对比其在313K温度下的吸收量、吸收速率以及393K温度下的再生速率、再生量以及它们的降解率。以筛选出较好的20∶4DETA+PZ烯胺复配药剂为基础,进行6次循环吸收-解吸实验,考察循环吸收、解吸性能与胺降解率;以智能高压反应釜分别考察了20∶4DETA+PZ降解性能,对CO_2负载、温度、铁离子的对降解性能的影响进行了探讨。     

三乙醇胺与烯胺混合胺液脱碳性能及配比优选实验研究

胺法脱碳以其脱除效果好、能耗低等优点在天然气预处理中得到广泛应用。目前国内外普遍采用以甲基二乙醇胺为主体的复配胺液为吸收剂,为适应寻找经济、高效的新型吸收剂的需求,本文选取同为叔胺的三乙醇胺(TEA)为主体进行实验研究,在TEA反应机理的研究基础上,添加二乙烯三胺/三乙烯四胺(DETA/TETA)进行混合胺液的吸收解吸性能分析,对比优选出综合表现较好的混合胺液,考察其不同配比下吸收、解吸及贴近实际生产的循环利用效果,完成配比优选研究。结果表明:添加烯胺后,可大大提高吸收性能,但会降低解吸效果;TEA+DETA吸收和解吸性能优于TEA+TETA;TEA+DETA的优选配比为2.0/1.0和2.4/0.6;经循环实验验证,2mol/L TEA+1mol/L DETA综合效果最佳。     

DETA-MDEA复合溶液吸收与解吸CO2实验研究

以烯胺吸收剂DETA(二乙烯三胺)为主吸收剂与辅助吸收剂MDEA(N-甲基二乙醇胺)按摩尔配比20:1～20:6进行复配,通过一次循环吸收、解吸实验,对比其在313 K温度下的吸收量、吸收速率以及393 K温度下的再生速率、再生量以及它们的降解率。以筛选出较好的20:4DETA+MDEA烯胺复配药剂为基础,进行6次循环吸收-解吸实验,考察循环吸收、解吸性能与胺降解率;以智能高压反应釜分别考察了20:4DETA+MDEA降解性能,对CO_2负载、温度、铁离子的降解性能的影响进行了探讨。     

TETA-MDEA复合溶液吸收与解吸CO_2实验研究

以烯胺吸收剂TETA(三乙烯四胺)为主吸收剂与辅助吸收剂MDEA(N-甲基二乙醇胺)按物质的量配比20∶1～20∶6进行复配,通过一次循环吸收、解吸实验,对比其在313K温度下的吸收量、吸收速率以及393K温度下的再生速率、再生量以及它们的降解率。以筛选出较好的20∶5TETA+MDEA烯胺复配药剂为基础,进行6次循环吸收-解吸实验,考察循环吸收、解吸性能;通过GC-MS对循环吸收和解吸降解产物进行分析,研究降解对吸收负荷的影响规律。     

可循环胺类吸收剂用于烟气脱碳的研究

在水相中,将二乙烯三胺(DETA)、三乙烯四胺(TETA)、四羟丙基乙二胺(EDTP)、四甲基乙二胺(TEMED)、三乙烯二胺(TEDA)分别与硼酸(H_3BO_3)等摩尔反应制得胺类烟气脱碳吸收剂。结果表明,TETA/H_3BO_3吸收剂对烟气具有良好的CO_2脱除性能和可再生性能,在吸收温度30.0℃、吸收剂浓度0.60 mol/L的吸收条件下,CO_2吸收容量为0.920 mol/L,脱碳率均大于99.5%,在恒沸温度101.5℃、时间60 min解吸条件下,初次解吸率大于72%。考察了吸收剂TETA/H_3BO_3的重复使用性能,经34次吸收-解吸循环实验结果表明,CO2吸收后富液p H为8.85±0.05,脱碳率均超过99.5%,解吸CO_2后贫液p H为10.40±0.05,后33次解吸效率均大于90%。     

可循环胺类吸收剂用于烟气脱碳的研究

在水相中,将二乙烯三胺(DETA)、三乙烯四胺(TETA)、四羟丙基乙二胺(EDTP)、四甲基乙二胺(TEMED)、三乙烯二胺(TEDA)分别与硼酸(H_3BO_3)等摩尔反应制得胺类烟气脱碳吸收剂。结果表明,TETA/H_3BO_3吸收剂对烟气具有良好的CO_2脱除性能和可再生性能,在吸收温度30.0℃、吸收剂浓度0.60 mol/L的吸收条件下,CO_2吸收容量为0.920 mol/L,脱碳率均大于99.5%,在恒沸温度101.5℃、时间60 min解吸条件下,初次解吸率大于72%。考察了吸收剂TETA/H_3BO_3的重复使用性能,经34次吸收-解吸循环实验结果表明,CO2吸收后富液p H为8.85±0.05,脱碳率均超过99.5%,解吸CO_2后贫液p H为10.40±0.05,后33次解吸效率均大于90%。     

TEPA-PZ复配溶液吸收二氧化碳实验研究

以烯胺吸收剂TEPA(四亚乙基五胺)为主吸收剂与辅助吸收剂PZ(哌嗪)按物质的量配比20∶1～20∶6进行复配,通过一次循环吸收、解吸实验,对啊比其在313K温度下的吸收量、吸收速率以及393K温度下的再生速率、再生量以及它们的降解率。以筛选出较好的20∶4TEPA+PZ烯胺复配药剂为基础,进行6次循环吸收-解吸实验,探讨了循环吸收、解吸性能。     

高浓度MDEA二元复配溶液回收CO2驱返排气中CO2研究

采用自主设计的搅拌反应釜压力装置,以CO_2和CH_4(1∶1,体积比)混合气体作为原料气,MDEA为主吸收剂,分别添加PZ、DEA、DETA和DIPA作为活化剂,复合体系总质量分数40%,优选最佳的CO_2驱返排气中CO_2回收MDEA复合体系。通过饱和吸收量、吸收速率、再生速率、再生率对比分析,得出各体系最佳配比分别为:35%MDEA+5%PZ、37%MDEA+3%DEA、35%MDEA+5%DETA、35%MDEA+5%DIPA。对4种优选的配方体系的吸收性能和再生性能进行综合分析,得出DETA对MDEA溶液吸收及再生性能提升最大,35%MDEA+5%DETA是最佳的二元复配溶液:吸收实验中最大吸收量为0.953 mol CO_2·mol~(-1)胺,最大平均吸收速率为5.822 mol CO_2·min~(-1),再生实验中最大再生率为95.3%,最大平均再生速率为27.4×10~(-3) mol CO_2·min~(-1)。     

离子液体-水复配吸收剂捕获CO2性能

基于绿色合成方法制备出亲水性离子液体(ILs)[NH₂-C₃mim][Br],从有效降低CO₂吸收-解吸操作成本出发,采用ILs-H₂O复配吸收剂,开展了常温加压CO₂吸收及吸收剂常温减压解吸再生实验。结果表明,比CO₂吸收量(基于复配吸收剂或离子液体组分)随复配吸收剂中ILs组分浓度而变;吸收初期,CO₂吸收速率随吸收剂配比变化显著;以CO₂高吸收率和吸收剂低成本为目标,优选出新型水基复配吸收剂(离子液体与水质量比为1.38:1)。分别以水基离子溶液、改良热钾碱液和活化复配醇胺液为吸收剂,在自行搭建的超重力场强化吸收-连续逆流接触(加热或减压)解吸再生台架实验装置上进行了CO₂捕获与吸收剂再生连续化实验。结果表明,在超重力场作用下,改良热钾碱液和活化复配醇胺液对CO₂有较好的捕获,吸收率分别在98%、96%和90%以上,3种吸收剂经加热或减压解吸再生后均可循环回用,水基离子溶液吸收剂在常温减压下解吸更具有实际可操作性。     

MDEA复配胺液脱除天然气中H2S性能

为了研究以N-甲基二乙醇胺（MDEA）为主体的MDEA+一乙醇胺（MEA）和MDEA+二乙烯三胺（DETA）两种配方混合胺液脱除H₂S性能,给工业中天然气脱硫配方提供参考和基础数据。利用小型反应釜进行吸收实验,使用单一MDEA胺液进行了工艺参数的筛选,同时考察吸收温度、吸收压力、再生温度对胺液脱除H₂S性能影响,得出升高吸收温度、吸收压力均可在一定程度内提升MDEA胺液的H₂S吸收效果,但当吸收温度过高时会降低胺液的H₂S吸收效果,吸收压力过高会造成脱硫成本的增加,筛选出最优吸收温度50℃,吸收压力5MPa,解吸油浴温度125℃。在优选出的实验工艺参数条件下进行不同添加剂对MDEA胺液脱除H₂S性能影响研究,考察不同配比的MDEA+DETA混合胺液和MDEA+MEA混合胺液脱除天然气中H₂S吸收及解吸性能。通过分析不同配比胺液的吸收负荷、吸收速率及解吸率等指标得出,MDEA单一胺液中添加二乙烯三胺（DETA）、一乙醇胺（MEA）胺液均可提升其H₂S吸收性能但并不利于胺液H₂S解吸性能的提升。性能较优配方为2.4mol/L MDEA+0.6mol/L MEA、2.4mol/L MDEA+0.6mol/L DETA混合胺液。     

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.     

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.     

ICP-MS法测定地球化学样品中As、Cr、Ge、V等18种微量痕量元素的研究

建立了测定地球化学样品中包括As、Cr、Ge、V等18种微量、痕量元素的ICP-MS方法。地化试样用HF-HNO3混酸分解后,以1 1 HNO3溶解干渣。由于制样不使用盐酸,避免了Cl对As、Cr、Ge、V的质谱干扰。用国家一级地球化学标准物质GBW 07309制备溶液优化仪器工作参数,并用于校准。方法测定限(6s)为:0.007~6.4μg/g,精密度(RSD%,n=12)为:29%~9.4%,经过国家一级地球化学标准物质的分析验证,结果与标准值吻合。方法已应用于国土资源调查的试样分析。