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1.
The physical properties and chemical components of three oil samples extracted from Illicium verum Hook. f. by steam distillation (SD), solvent extraction (SE) and supercritical fluid extraction (SFE) were compared with one another and analyzed by Gas Chromatography-Mass Spectrometry (GC-MS). The quality parameters of star anise essential oil from SFE were close to that of those came from SD and SE. Although the extraction yield of star anise by SFE (9.2 %) was close to the value from SE (9.3%), it was yet higher than that came from SD (8.2%). For sensory evaluation, however, three oils were significantly different. The odor and taste of the products from SFE and SE were generally more natural and vivid than that came from distilled oil. The volatile compound revealed that significant differences of the composition existed in the distilled oil and the oleoresins prepared by SFE and SE.  相似文献   

2.
The effect of treating algae-bearing water and induced odor by use of permanganate potassium composite (PPC) pre-oxidation was investigated, and was compared with the effect of treatments by pre-chlorination, permanganate petassium pre-oxidation and simple coagulation. The results showed that simple coagulation and pre-chlorination were less effective in removing algae and its odor, whereas PPC pre-oxidation was the most effective in algae removal and deodorization. Upon oxidation with PPC, the cells of Oscillatoria agardhic were inactivated and some intra-cellular and extra-cellular components were released into the water, which may help the coagulation by their bridging effect. The efficient removal of algae by PPC pre-oxidation is believed to be the joint contribution of several mechanisms.  相似文献   

3.
Oil cracking to gases: Kinetic modeling and geological significance   总被引:2,自引:0,他引:2  
A Triassic oil sample from LN14 of Tarim Basin was pyrolyzed using the sealed gold tubes at 200-620℃under a constant pressure of 50 MPa. The gaseous and residual soluble hydrocarbons were analyzed. The results show that the cracking of oil to gas can be divided into two distinct stages: the primary generation of total C1-5 gases from liquid oil characterized by the dominance of C2-5 hydrocarbons and the secondary or further cracking of C2-5 gases to methane and carbon-rich matters leading to the progressive dryness of gases. Based on the experimental data, the kinetic parameters were determined for the primary generation and secondary cracking of oil cracking gases and extrapolated to geological conditions to predict the thermal stability and cracking extent of crude oil. Finally, an evolution model for the thermal destruction of crude oil was proposed and its implications to the migration and accumulation of oil cracking gases were discussed.  相似文献   

4.
In this paper, ENVISAT ASAR data and the Estuary, Coastal and Ocean Model was used to analyze and compare characteristics of the Bohai Sea oil spill. The oil slicks have spread from the point of the oil spill to the east and north-western Bohai Sea. We make a comparison between the changes caused by the oil spill on the chlorophyll concentration and the sea surface temperature using MODIS data, which can be used to analyze the effect of the oil spill on the Bohai Sea ecosystem. We found that the Bohai Sea oil spill caused abnormal chlorophyll concentration distributions and red tide nearby area of oil spill.  相似文献   

5.
QRF Burner can control the ratio of the oil and air autmotically by follow the change of fuel oil pressure. The temperature of the preheated air can be up to 550℃, since steam is adopted as heat insulation material. So it can sa-  相似文献   

6.
Oil pollution can be monitored by infrared remote sensing technology. In this work, the degree of po-larization (DOP) was established as a quantitative index of oil pollution. The crude oil and the local typical surface soil from the Songyuan oil field in Jilin province were collected. Some soil samples with four levels of oil content and three levels of water content were prepared and measured. The DOP of the polluted soil and the clean soil in the field was also measured at 180° relative viewing azimuth a...  相似文献   

7.
It is demonstrated by various geochemical indexes that the Zhengjia-Wangzhuang Oilfield with viscous crude oil in the Jiyang Depression has been sourced from the contribution of matured source rocks in the upper Es4. The principal cause leading to the densification of crude oils would be biodegradation, with the degradation level of crude oils being ranked as 2-8; vertically, the biodegradation level increases from the top to bottom of the oil column, with a distinctive biodegradation gradient occurring. Calculated parameters of sterane, terpane and methyl-phenanthrene have indicated that the source-rock's maturity of crude oils and asphaltic sands ranges from 0.7 to 0.9, and based on the calculation of Easy Ro model, the temperature of hydrocarbon generation in the source rock would be within 120-140℃, which coincides with the measurements of reservoir inclusions. The measured homogenization temperature would represent the generation temperature of the source rock, and be fairly different from that of reservoir while being charged with hydrocarbons, which reflects the hydrocarbon-charging to be a fast process, and the period of pool-formation to be consistent with that of peaked generation. According to the evaluation of generation history, the pool-formation could have been occurring in 7-15 Ma. And the biodegradation of crude oils in the study area would be considered to take place in 4-15 Ma based on the examination of biodegradation order and dynamic calculations.  相似文献   

8.
The potentials of gas generation by kerogen in the late period and by crude oil cracking are closely related to the origin of natural gas in the high- to over mature marine area and their exploration perspectives. The carbon structure of kerogens, with different types and at different evolution stages, have been experimentally studied using the high magnetic field solid ^13C nuclear magnetic resonance technique in order to determine the oil and gas potential of kerogens. Results show that the contents of gas potential carbon(GPC) of types Ⅰ, Ⅱ, Ⅲ kerogens at the high- to over mature stage are very low, indicating their weak gas-generating capacity and limited gas production; however, the content of oil potential carbon(OPC) of the low mature type Ⅰ kerogen is much higher, implying that a large amount of crude oil generated during the oil-generating period will be the material for later gas generation by oil cracking. The kinetic experiment of gas generation by crude oil cracking shows that, when the temperature is about 160℃(R0=1.6%), the crude oil will start to produce large amounts of gas; the temperature range for major gas generation of crude oil is higher than that of the kerogens, and the gas production is 2 to 4 times higher than that of kerogens. The natural gas derived from oil cracking (called oil-cracked gas) is much abundant in methyl hexamethylene, which is quite different from the natural gas produced by thermal degradation of kerogens (named kerogen degradation gas) at high- to over mature stage.  相似文献   

9.
The Ordovician buried hill reservoir in the western Lunnan area, a type of dissolved fracture and cavernous reservoir, is mainly composed of heavy oil. The oil is the mixture sourcing from the Middle-Lower Cambrian and Middle-Lower Ordovician, with three stages of pool forming process: (1) the destruction and parallel migration/accumulation during the late Caledonian to early Hercynian; (2) the oil and gas accumulation during the late Hercynian characterized by adjustment upward along faults and parallel migration/accumulation; (3) the formation of heavy oil during the latest Hercynian. The Ordovician buried hill reservoir is affected by the diffusion of light oil and gas but had no hydrocarbon charging during the late Yanshan period to Himalayan period, but in this period, formed the association of heavy oil and dissolved gas cracked from crude oil with dry coefficient of 0.91-0.96. The study on accumulation process of the Ordovician buried hill reservoir has important implications for the exploration potential of early oil and gas accumulation in the cratonic area of the Tarim Basin.  相似文献   

10.
The Ordovician buried hill reservoir in the western Lunnan area, a type of dissolved fracture and cavernous reservoir, is mainly composed of heavy oil. The oil is the mixture sourcing from the Middle-Lower Cambrian and Middle-Lower Ordovician, with three stages of pool forming process: (1) the destruction and parallel migration/accumulation during the late Caledonian to early Hercynian; (2) the oil and gas accumulation during the late Hercynian characterized by adjustment upward along faults and parallel migration/accumulation; (3) the formation of heavy oil during the latest Hercynian. The Ordovician buried hill reservoir is affected by the diffusion of light oil and gas but had no hydrocarbon charging during the late Yanshan period to Himalayan period, but in this period, formed the association of heavy oil and dissolved gas cracked from crude oil with dry coefficient of 0.91-0.96. The study on accumulation process of the Ordovician buried hill reservoir has important implications for the exploration potential of early oil and gas accumulation in the cratonic area of the Tarim Basin.  相似文献   

11.
文章在纯轮换移位寄存器的状态图中,定义了圈的"比重",并利用"比重"的特性,给出了2元deBruijn序列的一个生成算法,其算法速度较快;同时该算法能生成2s.g(n,s)个n级de Bruijn序列,其中1≤s≤2(n-24),g(n,s)=n-2l-6-[n-l 2 l1-6]。  相似文献   

12.
高校行政化是我国高等教育的顽疾,从办学管理、人才培养、教学科研活动、师生关系、环境建设等诸多方面影响到了高等教育的健康和谐发展。其中有体制的原因,也有高等教育法制建设滞后的原因。本文从高等教育行政化的各种表现人手,分析高等教育出现行政化的原因及给高校发展带来的负面影响,并钊‘对高等教育去行政化进行了“冷思考”。  相似文献   

13.
探讨"德才兼备"的"德"的现实意义,以纯净党的干部标准.  相似文献   

14.
建立由丁香花蕾提取丁香酚的新方法-乙醇回流法,使丁香酚的提取率由原来的5.0%提高到10.3%.采用羰基铁作催化剂,使丁香酚转化为异丁香酚,然后在不亲核碱二异丙氨基锂(LDA)的作用下,以无水四氢呋喃为溶剂,使苄基氯与异丁香酚反应,生成苄基异丁香酚,产率达到95.0%,纯度达到99.0%以上,并通过IR和NMR技术表征了产物的结构.  相似文献   

15.
"多的是"在现代汉语句子中的不同分布位置反映了不同的语法属性,且各有其历史来源,其发展的历史和现状受到了"有的是"的影响。  相似文献   

16.
以2-氯-吲哚-3-甲醛(1)为原料,在碱性条件下发生烷基化反应,对反应的烷基化试剂、溶剂等因素对收率的影响进行了研究,以较高收率合成了N-取代-2-氯-3-吲哚醛类化合物(2a-2e),其中化合物(2a-2e)均是未见文献报道的新化合物。所有新化合物的结构通过红外光谱、质谱及核磁共振氢谱得以证实。  相似文献   

17.
在绿色开采思想的指导下,对关键层理论在保水开采中的应用进行了分析。通过算例讨论了三者的关系并分析了岩层变形一渗流耦合系统的复杂性特征,提出应用复杂系统动力学理论解释突水机制的初步设想。研究表明,在承载关键层破断前,承载关键层同时也是保水关键层;在承载关键层破断后,不再具有隔水作用,而保水关键层此时由渗流关键层充当;如果承载关键层破断,并且渗流关键层不存在,则会发生突水现象。岩层变形一渗流耦合动力学系统是具有时变边界、非线性、非均匀性和非连续性等特征的复杂系统。将复杂系统动力学引入突水防治理论研究,可以从本质上描述突水的过程。  相似文献   

18.
着重从语义和语用两个方面比较分析了靖远方言与普通话中"称谓词+的"的异同,突出了靖远方言中"称谓词+的"的特殊之处。  相似文献   

19.
2—取代环酮与芳香胺的Mannich反应   总被引:1,自引:1,他引:1  
2-乙氧羰基环戊酮,2-乙氧羰基环己酮或2-在酰基环己酮与w=37%的甲醛水溶液和对位取代苯胺,在HCl-EtOH溶液中可直接发生Mannich反应,将芳氨基甲基引入2位,得到2-芳氨基甲基-2-乙氧羰基环戊酮盐酸盐、2-芳氨基甲基-2-乙氧羰基环己酮或2-芳氨基甲基-2-乙酰基环己酮,共合成11个新化合物,2-乙氧羰基环戊酮与苯亚甲基芳胺在乙胺溶液中回流,将芳氨基甲基引入5位,得到5-芳氨基苯基  相似文献   

20.
5-Br-PADAP在H_2SO_4介质中质子化,与Cr_2O_7~(2-)和SCN~-形成紫红色的三元离子缔合物,其最大吸收波长为540nm,Cr_2O_7~(2-)在0.0~20.8μg/10ml范围内符合比耳定律,其表现摩尔吸光系数ε_(540)=6.20×10~4L·mol~(-1)。应用于水样和钢样中微量Cr_2O_7~(2-)的测定,取得满意结果。  相似文献   

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