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煤液化油中酚类化合物分布特征研究 总被引:1,自引:0,他引:1
采用气相色谱/质谱联用研究分析了胜利褐煤在0.1t/d直接液化连续实验装置上所得煤液化油中酚类化合物的分布特征.实验通过碱液洗涤法富集煤液化油中混合酚组分,并对该组分进行衍生化处理,以提高色谱柱对混合物的分离性能.以混合衍生物为主要分析对象,共定性出煤液化油中134种个体酚,分属于苯酚、茚满酚、萘满酚和萘酚等四种类型,且绝大多数酚类化合物都带有烷基侧链.苯酚类化合物数量最多,在混合酚组分中含量最大,其次为茚满酚和萘满酚.萘酚类化合物的数量最少,相对含量最小. 相似文献
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为提高煤在萃取过程中的转化率,考察微波辅助萃取煤的工业化可行性。在微波辅助下,以神府低温煤焦油馏分为溶剂,在最优操作条件下萃取神府煤,将萃取混合液在510℃条件下热解,分析了热解液体产物的性质及组成,得到了加工方案。结果表明:液体产物主要由酚类化合物、芳烃化合物及烷烃组成,酚类含量较高,其在萃取热解液体产物中的比例均达到50%以上,主要由苯酚、C1~C4苯酚组成,大于C4苯酚的含量很小,其中由苯酚、C1-苯酚、C2-苯酚组成的低级酚含量占总酚含量的70%以上,因此对液体产物进行加工时,需要将低级酚类化合物从液体产物中先分离出来。 相似文献
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以中低温煤焦油为原料,首先利用实沸点蒸馏装置得到中低温煤焦油的酚油馏分,并对酚油馏分的理化性质进行分析评价,然后对酚油馏分进行酸碱抽提处理得到碱抽提油和抽余油并进行元素分析,再利用衍生化处理和气相色谱相结合的方法对碱抽提油中的酚类化合物进行定性定量分析。结果表明:中低温煤焦油中170℃~230℃的酚油馏分收率为11.58%(质量分数),酸性组分约占酚油馏分油的65.23%(质量分数),且酚油馏分酸度高达62.04mgKOH/100mL;酚油馏分中低级酚含量很高,其中苯酚质量分数为5.84%,甲酚质量分数为20.70%,乙基苯酚质量分数为7.70%,二甲基苯酚质量分数为9.17%。酚油馏分经酸碱抽提后,含氧化合物绝大部分转移到富含酸性组分的碱抽提油中,碱抽提油中氧的质量分数高达15.11%。碱抽提油中甲酚含量最高,其中间甲酚质量分数为13.41%,对甲酚质量分数为9.24%,邻甲酚质量分数为9.09%。 相似文献
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农作物秸秆快速热解生物油主要成分分析 总被引:2,自引:1,他引:1
采用自行研发的真空快速热解反应平台对棉秆、玉米秸秆和稻草秆进行了快速热解,并用气质联用(GC-MS)分析法分别对3种秸秆快速热解液相产物的化学组分进行了测定。实验结果表明:棉秆、玉米秸秆和稻草秆3种热解油中酚类GC含量分别为24.34%、21.21%和17.22%,酸类GC含量分别为14.78%、13.95%和16.69%;不同种类秸秆其热解液化产物在组分及含量上存在一定差别,但其成分均以苯酚类、醛类、酮类、有机酸类等化合物为主,且含量差异不大,其中玉米秸秆和棉秆各类化合物含量差异相对较小,因此,生产中可以将成分类似却不同种类的原料混合热解。 相似文献
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烟煤固体热载体低温快速热解实验研究 总被引:2,自引:1,他引:1
以连续式热解装置为实验平台,藁城和府谷煤为原料,石英砂为热载体,考察了460~520℃范围内热解所得气、液产物收率、组成和性质的变化规律. 结果表明,在考察的温度范围内,提高热解温度,热解气、液产物收率增加,液体产物收率最高可达12%左右. 热解温度对热解产物中不凝气组成影响显著,热解煤气热值高达25 MJ/Nm3以上. 焦油组分中酚衍生物含量最高,稠环烃、芳香烃、链烃组分的含量也较高,酚含量随热解温度增高有所降低,而芳烃含量则显著提高. 根据实验结果提出了酚-芳烃转化的可能路径. 相似文献
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《过程工程学报》2017,(6)
对油页岩在不同终温热解所得半焦进行溶剂萃取,得到了热解中间产物(热解沥青)和终产物.采用气相色谱-质谱联用仪分析了热解沥青和页岩油的组成,采用热裂解-气相色谱-质谱联用仪检测了热解沥青的裂解产物,并与热解页岩油进行对比,研究了油页岩热解沥青的反应特性.结果表明,油页岩热解沥青在最快产油阶段生成最多且稳定存在,375℃时收率最大;375~400℃时热解产油速率最大,热解沥青收率下降,表明热解沥青在高温下不稳定,有机质生成中间产物后便转化成终产物.随热解温度升高,热解沥青中轻质组分含量增加.杂原子化合物最先从有机质上断裂进入中间产物,而热解油中烯烃化合物大部分来自有机质直接裂解,来自热解沥青裂解的较少.热解温度升高,热解沥青的裂解产物中烯烃含量增加,且热解沥青中芳香烃的长侧链易通过裂解变短. 相似文献
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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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M. S. J. Simmonds W. M. Blaney F. Delle Monache M. Marquina Mac-Quhae G. B. Marini Bettolo 《Journal of chemical ecology》1985,11(12):1593-1599
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
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Cheng-Le Zhao Shane Porzio Alan Smith Haiyan Ge H. T. Davis L. E. Scriven 《Journal of Coatings Technology and Research》2006,3(2):109-115
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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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. 相似文献
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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 总被引:15,自引:0,他引:15
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。 相似文献
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