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1.
将神府煤在不同过氧化氢投加量时进行光氧化解聚,对氧化后煤的丙酮和甲醇萃取液进行分析,并与原煤样进行对照.结果发现:过氧化氢是神府煤光催化氧化解聚过程中主要的引发剂和氧化剂,其浓度对氧化效果有重要影响,但并非投加量越高越好;当过氧化氢的投加量为1.00mL时,光催化氧化的含氧化合物的相对含量最大,可达41.4%;随着光催化氧化反应的进行,氧化煤中含氧化合物相对含量激增,支链烃(包括支链烷烃和支链芳烃)的含量明显减少;另外极性不同的萃取剂对氧化煤萃取得到的萃取物组成不尽相同,极性强萃取剂能析出氧化煤中更多的酮类和酯类物质;联二苯为氧化煤中主要的有机化合物,应该为苯环上氢原子被光解形成苯自由基,然后苯自由基相互作用而形成,过氧化氢在这一过程中起到了夺氢供氧的作用.  相似文献   

2.
以TiO2为光催化剂,双氧水(H2O2)为氧化剂,通过红外光谱分析和气相色谱质谱分析减渣催化氧化产物的组成与结构特征,考察TiO2和双氧水用量对大港减压渣油环己烷溶液体系的催化转化效果.结果表明:大港减压渣油环己烷溶液被光催化氧化后,烷烃、醇、醚和酯等小分子物质的相对含量明显增加;TiO2与双氧水共用可协同促进渣油的氧化,其氧化后的小分子相对含量收率可达28.51%,而单用双氧水的收率仅为13.43%.  相似文献   

3.
为了研究氧化预处理对后续酯化效果的影响,利用生物油模型化合物进行了氧化预处理以及酯化实验.以糠醛、乙酸、丙酮、乙醇配制模型化合物,选取过氧化氢、臭氧为氧化剂进行氧化处理实验,通过酸值、GCMS以及红外光谱等分析研究了氧化时间(0~2 h)、过氧化氢量(20~60m L)、氧化剂种类对氧化处理及后续酯化效果的影响.研究表明:在氧化过程中,增加过氧化氢量能够提高氧化处理能力,但增强效果并不明显;在几种不同的氧化方式中,过氧化氢和臭氧联合氧化为相对较优的氧化处理方式;相比于模型化合物直接酯化的酯含量7.8%,经过氧化处理后,模型化合物酯含量上升到了24.9%及以上.酯化提质前进行氧化预处理,可有效增强酯化效果.  相似文献   

4.
为实现依兰油页岩萃取物中含氧化合物的分离与分析,采用索氏萃取法,在60℃条件下以CS2-NMP为萃取剂萃取依兰油页岩。用TiCl4/CuCl2两步络合法和硅胶柱色谱法对依兰页岩油中的含氧化合物进行富集,并对含氧洗脱组分进行了气相色谱-质谱串联(GC/MS)分析。结果表明:TiCl4/CuCl2两步络合法可以实现油页岩中含氮化合物的分离,脱氮率为82%,硅胶柱色谱可以实现对页岩油中含氧化合物的富集,富集组分中,氧元素的质量分数为10.69%;柱色谱富集组分中鉴定出32种含氧化合物,其组成以酚、酮、醚、酯以及有机硅氧化合物为主;在这些含氧化合物中发现了甾醇类、萜类化合物的衍生物以及酰胺基团,说明依兰油页岩中的氧可能来源于成矿的高等植物和蓝绿藻。该结果可以为依兰油页岩资源的合理利用、油页岩的成因和油母结构研究提供参考。  相似文献   

5.
大港减渣超临界萃取物的GC/MS定性、定量分析   总被引:1,自引:0,他引:1  
超临界萃取可以在控制的温度和压力下把重油分成很多窄馏分以方便后续分析,从大港原油真空分馏得到的大港减渣被超临界萃取技术分成F1到F16个级分.用商品级的石蜡作为外标.用GC/MS对这些级分进行定性和定量分析,分析结果显示用其主要成分为C15到C43的直链烷烃,包含藿烷、萜烯和含氧有机化合物等,这些化合物的浓度从F1到F16明显减少.  相似文献   

6.
本研究为进一步分析残余煤中的有机成分,采用的是甲醇溶剂对枣庄残余煤进行了索氏萃取,并利用GC/MS/MS对萃取物的组成进行了分析.结果表明枣庄残余煤甲醇萃取物中GC/MS/MS可检测到化合物46种,其中酯类占多数,其次是脂肪烃,芳香烃占少数,含部分含氮化合物.这可推测氧化后的残余煤样中可能含有的烃类物质为芳香烃、脂肪烃,含氧化合物有醇、吡啶及醚类,还可能有胺类和芳香硝基化合物.  相似文献   

7.
以表面活性剂聚乙二醇(PEG-6000)为模板剂,采用溶胶-凝胶法制备了溴氧化铋(BiOBr-PEG)光催化剂,运用XRD、SEM、BET和DRS对其结构及光化学特性进行了初步表征.在可见光(λ≥420nm)照射下,以有机污染料罗丹明B(Rhodamine B,RhB)和无色小分子水杨酸(Salicylic acid,SA)为目标化合物,研究了其光催化降解反应特性.结果表明:BiOBr-PEG具有优越的光催化活性,对RhB和SA都具有较好的降解效果,可见光照射40min和12h后,RhB和SA降解率分别达到98%和41%.同时,BiOBr-PEG催化剂稳定性良好,循环使用5次光催化活性基本稳定.光催化降解过程中涉及·OH和O·-2的氧化机理.  相似文献   

8.
为了研究超声辅助过氧化氢-乙酸氧化脱除煤中有机硫的机理,选取4种脱灰煤和6种含硫模型化合物作为研究对象,探讨反应温度、反应时间和超声功率对有机硫的脱除影响;采用X射线光电子能谱、傅里叶变换红外光谱、扫描电子显微镜等手段,对脱硫处理前、后的样品进行表征.结果表明:超声辅助过氧化氢-乙酸脱硫时,有机硫化物硫的含量越高,脱硫...  相似文献   

9.
大气中的挥发性含氧有机物(oxygenated volatile organic compounds,OVOCs)主要由醛、酮、醇、酸、醚、酯及极其活泼的烯醛、烯酮等化合物组成.挥发性含氧有机物对大气化学的研究起着十分重要的作用:一方面OVOCs拥有较高的反应活性可直接参与大气光化学反应过程,进而形成臭氧等强氧化性的污染物.另一方面OVOCs对二次有机气溶胶的形成(secondary organic aerosol,SOA)影响显著,是SOA生成的重要前体物.研究表明,OVOCs不仅在大气光化学反应中起到重要作用,而且会对人体造成一定危害,具有致癌、致畸、致突变等危害,因此受到国内外学者的广泛关注.OVOCs的来源广泛,其中主要包括自然源、人为源以及大气光化学反应的二次转化过程.其在大气中的浓度变化范围大,反应活性高,且许多挥发性含氧有机物寿命短、含量低.这些特点使得对其采样及测量方法有着非常严格的要求:检测方法应有较高的灵敏度,且能实现痕量水平的分析;采样及分析过程需避免目标物的降解或转化.挥发性含氧有机物的分析方法包括离线分析法与在线连续分析法,其中离线分析法包括化学衍生法、气相色谱法(GC)、高效液相色谱法(HPLC)等方法,在线连续分析法包括在线气相色谱技术、质子转移质谱(PTR-MS)等方法,其中2,4-二硝基苯肼(DNPH)-高效液相色谱(HPLC)法应用最广.  相似文献   

10.
通过对固体可燃物质燃烧热测定方法的改进,测定挥发性液体的燃烧热。实验采用氧弹量热计,将化合物注入胶囊中测其燃烧热,并保证化合物在实验过程中不溢出,不挥发,又要易于点燃。以柴油为参照测定含氧化合物(正丁醚、二甘醇二甲醚、二乙二醇丁醚和乙二醇丁醚)的燃烧热。实验测得,柴油的燃烧热Q柴油=-42.452 k J/g,四种含氧燃料中燃烧热值最高的是乙二醇丁醚和正丁醚:Q乙二醇丁醚=-43.143 k J/g,Q正丁醚=-42.111 k J/g。  相似文献   

11.
Language markedness is a common phenomenon in languages, and is reflected from hearing, vision and sense, i.e. the variation in the three aspects such as phonology, morphology and semantics. This paper focuses on the interpretation of markedness in language use following the three perspectives, i.e. pragmatic interpretation, psychological interpretation and cognitive interpretation, with an aim to define the function of markedness.  相似文献   

12.
何延凌 《科技信息》2008,(4):258-258
Language is a means of verbal communication. People use language to communicate with each other. In the society, no two speakers are exactly alike in the way of speaking. Some differences are due to age, gender, statue and personality. Above all, gender is one of the obvious reasons. The writer of this paper tries to describe the features of women's language from these perspectives: pronunciation, intonation, diction, subjects, grammar and discourse. From the discussion of the features of women's language, more attention should be paid to language use in social context. What's more, the linguistic phenomena in a speaking community can be understood more thoroughly.  相似文献   

13.
The discovery of the prolific Ordovician Red River reservoirs in 1995 in southeastern Saskatchewan was the catalyst for extensive exploration activity which resulted in the discovery of more than 15 new Red River pools. The best yields of Red River production to date have been from dolomite reservoirs. Understanding the processes of dolomitization is, therefore, crucial for the prediction of the connectivity, spatial distribution and heterogeneity of dolomite reservoirs.The Red River reservoirs in the Midale area consist of 3~4 thin dolomitized zones, with a total thickness of about 20 m, which occur at the top of the Yeoman Formation. Two types of replacement dolomite were recognized in the Red River reservoir: dolomitized burrow infills and dolomitized host matrix. The spatial distribution of dolomite suggests that burrowing organisms played an important role in facilitating the fluid flow in the backfilled sediments. This resulted in penecontemporaneous dolomitization of burrow infills by normal seawater. The dolomite in the host matrix is interpreted as having occurred at shallow burial by evaporitic seawater during precipitation of Lake Almar anhydrite that immediately overlies the Yeoman Formation. However, the low δ18O values of dolomited burrow infills (-5.9‰~ -7.8‰, PDB) and matrix dolomites (-6.6‰~ -8.1‰, avg. -7.4‰ PDB) compared to the estimated values for the late Ordovician marine dolomite could be attributed to modification and alteration of dolomite at higher temperatures during deeper burial, which could also be responsible for its 87Sr/86Sr ratios (0.7084~0.7088) that are higher than suggested for the late Ordovician seawaters (0.7078~0.7080). The trace amounts of saddle dolomite cement in the Red River carbonates are probably related to "cannibalization" of earlier replacement dolomite during the chemical compaction.  相似文献   

14.
理论推导与室内实验相结合,建立了低渗透非均质砂岩油藏启动压力梯度确定方法。首先借助油藏流场与电场相似的原理,推导了非均质砂岩油藏启动压力梯度计算公式。其次基于稳定流实验方法,建立了非均质砂岩油藏启动压力梯度测试方法。结果表明:低渗透非均质砂岩油藏的启动压力梯度确定遵循两个等效原则。平面非均质油藏的启动压力梯度等于各级渗透率段的启动压力梯度关于长度的加权平均;纵向非均质油藏的启动压力梯度等于各渗透率层的启动压力梯度关于渗透率与渗流面积乘积的加权平均。研究成果可用于有效指导低渗透非均质砂岩油藏的合理井距确定,促进该类油藏的高效开发。  相似文献   

15.
As an American modern novelist who were famous in the literary world, Hemingway was not a person who always followed the trend but a sharp observer. At the same time, he was a tragedy maestro, he paid great attention on existence, fate and end-result. The dramatis personae's tragedy of his works was an extreme limit by all means tragedy on the meaning of fearless challenge that failed. The beauty of tragedy was not produced on the destruction of life, but now this kind of value was in the impact activity. They performed for the reader about the tragedy on challenging for the limit and the death.  相似文献   

16.
AcomputergeneratorforrandomlylayeredstructuresYUJia shun1,2,HEZhen hua2(1.TheInstituteofGeologicalandNuclearSciences,NewZealand;2.StateKeyLaboratoryofOilandGasReservoirGeologyandExploitation,ChengduUniversityofTechnology,China)Abstract:Analgorithmisintrod…  相似文献   

17.
There are numerous geometric objects stored in the spatial databases. An importance function in a spatial database is that users can browse the geometric objects as a map efficiently. Thus the spatial database should display the geometric objects users concern about swiftly onto the display window. This process includes two operations:retrieve data from database and then draw them onto screen. Accordingly, to improve the efficiency, we should try to reduce time of both retrieving object and displaying them. The former can be achieved with the aid of spatial index such as R-tree, the latter require to simplify the objects. Simplification means that objects are shown with sufficient but not with unnecessary detail which depend on the scale of browse. So the major problem is how to retrieve data at different detail level efficiently. This paper introduces the implementation of a multi-scale index in the spatial database SISP (Spatial Information Shared Platform) which is generalized from R-tree. The difference between the generalization and the R-tree lies on two facets: One is that every node and geometric object in the generalization is assigned with a importance value which denote the importance of them, and every vertex in the objects are assigned with a importance value,too. The importance value can be use to decide which data should be retrieve from disk in a query. The other difference is that geometric objects in the generalization are divided into one or more sub-blocks, and vertexes are total ordered by their importance value. With the help of the generalized R-tree, one can easily retrieve data at different detail levels.Some experiments are performed on real-life data to evaluate the performance of solutions that separately use normal spatial index and multi-scale spatial index. The results show that the solution using multi-scale index in SISP is satisfying.  相似文献   

18.
In the 19th century the society was controlled by men, and women were just appendants of them, they had not any rights and freedom. But Jane was an exception, she showed some characteristics of early feminist. Jane showed her characteristics of feminism in three aspects: rebellion, equality, and independence. These characteristics were helpful to her success, and feminism is the only way out for women of that time.  相似文献   

19.
正The periodicity of the elements and the non-reactivity of the inner-shell electrons are two related principles of chemistry,rooted in the atomic shell structure.Within compounds,Group I elements,for example,invariably assume the+1 oxidation state,and their chemical properties differ completely from those of the p-block elements.These general rules govern our understanding of chemical structures and reactions.Using first principles calcula-  相似文献   

20.
We have developed an adiabatic connection to formulate the ground-state exchange-correlation energy in terms of pairing matrix linear fluctuations.This formulation of the exchange-correlation energy opens a new channel for density functional approximations based on the many-body perturbation theory.We illustrate the potential of such approaches with an approximation based on the particle-particle Random Phase Approximation(pp-RPA).This re-  相似文献   

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