MCM-41固载席夫碱钴配合物在环己烷氧化反应中的应用

制备γ-氨丙基三乙氧基硅烷修饰的MCM-41分子筛固载型双水杨醛缩乙二胺合钴(Cosalen)配合物,采用傅里叶变换红外光谱、X线衍射、比表面积测定、热重-差热(TG-DSC)、紫外-可见光光谱(UV-Vis)、透射电镜等方法对分子筛固载型配合物Cosalen/MCM-41的结构进行表征,并对比Cosalen/MCM-41与Cosalen/NaY的催化性能。研究结果表明:Cosalen已进入分子筛孔道内;在以氧气为氧源的环己烷氧化反应中,Cosalen/MCM-41催化剂具有较好的活性和对环己醇、环已酮的选择性。该催化反应产物中环已基过氧化氢(CHHP)的量很少,表明Cosalen/MCM-41催化剂能加速环已基过氧化氢的分解;以Cosalen/MCM-41为催化剂,在初始氧气压力为0.80 MPa,温度为130℃,环己烷与催化剂的质量比为100,叔丁基过氧化氢0.06 g的相对温和条件下反应2 h,环己烷的转化率达到5.96%,醇酮选择性87.03%。     

甲基修饰Au/MCM-41催化环己烷选择氧化

介绍了一种提高环己烷氧化制备环己酮/环己醇催化效率的方法.通过对Au/MCM-41催化剂进行甲基化修饰以提高其表面的疏水性,从而提高环己烷催化氧化的效率.结果表明,在相同反应条件下,甲基化修饰的催化剂Au/CH3-McM-41比未修饰的催化剂Au/MCM-41表现出更高的催化效率,Au/CH3-McM-41优异的催化性能是由于甲基的引人改变了Au活性位的周围环境引起的.     

锡修饰MCM-41的合成、表征及催化应用

以硅酸钠为硅源,十六烷基三甲基溴化铵为模板剂,锡酸钠为金属源,水热法直接合成一系列不同含量Sn掺杂的MCM-41分子筛,采用XRD、N2吸脱附、FTIR和ICP对材料的结构和物化性质进行表征。以乙腈为溶剂,H2O2为氧化剂,70℃考察了所合成的材料对环己烷液相氧化的催化活性和选择性的影响。结果表明:随着锡含量的增加,环己烷的转化率增加趋缓,环己醇的选择性减小而环己酮的选择性增大。     

纳米氧化铁的制备及其对环己烷氧化性能的影响

采用超声波方法在不同浓度的五羰基铁溶液中制备得到纳米氧化铁,并将其为催化剂用于环己烷催化氧化反应。在反应体系中,考察了反应时间、温度、催化剂用量、引发剂用量、空气量对催化氧化反应的影响。结果表明,以叔丁基过氧化氢为引发剂,空气为氧化剂在70℃,常压下反应3h,环己烷转化率可以达到23.8%,环己醇、环己酮和环己基过氧化氢的选择性可达94.5%.     

H6P2Mo9W9O62/MCM-41催化合成环己酮乙二醇缩酮

目的合成环己酮乙二醇缩酮。方法采用浸渍法制备了H_6P_2Mo_9W_9O_(62)/MCM-41催化剂,并采用FT-IR、XRD对其进行了表征。以环己酮和乙二醇为原料,催化合成环己酮乙二醇缩酮,采用FT-IR表征手段来表征合成产物。结果经反应条件优化,在酮醇摩尔比为1∶1.3,带水剂环己烷用量为8 mL,催化剂用量为反应物总质量的0.8%,反应时间为60 min的条件下,缩酮收率可达82.6%。催化剂重复使用5次后收率仍有73.5%。结论催化剂H_6P_2Mo_9W_9O_(62)/MCM-41对合成环己酮乙二醇缩酮具有反应时间短、催化剂用量少、产品收率高等优点。     

含过渡金属分子筛催化环己醇与空气氧化制备环己酮

分别采用离子交换法、水热合成法和干胶转化晶化法,将非贵过渡金属引入到分子筛中合成出含过渡金属的分子筛催化剂,并将其应用于以空气为氧化剂、多相催化环己醇合成环己酮的反应中,探索高效、环保、廉价的绿色催化氧化反应体系.研究结果表明,采用水热合成法制备的含钴分子筛(CoAlPO-5)在催化空气氧化环己醇制备环己酮的反应中表现出优异的催化活性,通过考察反应温度、空气流速、反应时间、催化剂用量等探索了最佳催化反应条件是:反应温度为100℃、空气流速为40mL/min、反应时间为8h、催化剂用量为100mg时,环己醇转化率可达到38.2%,环己酮选择性达到95.8%.     

希夫碱锰催化氧化环己烯合成环己烯酮

以MCM-41型介孔分子筛为载体,制备出固载型金属希夫碱锰催化剂,并用红外、紫外漫反射对其结构进行了表征.以固载型金属希夫碱锰为催化剂,对分子氧氧化环己烯制备环己烯酮的工艺条件进行了探索,结果表明,在催化剂用量:0.2g,温度:60℃,时间:9h,溶剂:乙腈的条件下,环己烯转化率可达90.9%,环己烯酮的选择性可达55.8%,催化剂重复使用4次后活性略有下降.     

NHPI复合体系催化氧化环己烷的研究进展

环己烷氧化制备环己酮和环己醇是一个重要的工业过程,但目前满足绿色环保和便于工业化应用的催化剂或反应工艺很少,N-羟基邻苯二甲酰亚胺(NHPI)催化剂因其能在温和条件下有效地催化烃类自由基氧化而受到广泛关注.本文综述了近年来NHPI复合催化体系催化氧化环己烷的实验路线.分析表明NHPI复合催化剂能明显地提高环己烷的转化率和环己酮的选择性,但普遍存在反应时间长,热稳定性差,可回收率低等缺点.因而开发更高效的NHPI复合催化剂,对环己烷氧化工艺及其工业化应用具有重要的现实意义.     

过渡金属离子交换分子筛催化空气氧化环己醇制备环己酮

以空气为氧化剂,过渡金属离子交换的分子筛为催化剂,催化氧化环己醇制备环己酮.结果表明,Cr-ZSM 5在催化空气氧化环己醇制备环己酮的反应中展现出较好的催化活性.通过考察反应时间、反应温度、空气流速及催化剂用量等,探讨催化氧化环己醇制备环己酮的最佳反应条件.     

VPO复合物催化环己烷一步合成己内酰胺

在有机介质中设计和制备了一系列过渡金属掺杂的还原型VPO复合催化剂,并应用于环己烷液相亚硝化一步合成己内酰胺的反应.结果表明,己内酰胺可以直接通过一步催化过程获得.在这些还原型的VPO复合催化剂中,发现Mn-AI-VPO复合催化剂具有较好的催化效果:己内酰胺的选择性可达48.86%.环己烷的转化率为20.19%.该方法为己内酰胺的合成路线提供了一种全新的思路.     

Markedness and its Interpretation in Language Use

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.     

Lower Paleozoic oil relationships within Williston Basin, Canada

The Williston Basin is a significant petroleum province, containing oil production zones that include the Middle Cambrian to Lower Ordovician, Upper Ordovician, Middle Devonian, Upper Devonian and Mississippian and within the Jurassic and Cretaceous. The oils of the Williston Basin exhibit a wide range of geochemical characteristics defined as "oil families", although the geochemical signature of the Cambrian Deadwood Formation and Lower Ordovician Winnipeg reservoired oils does not match any "oil family". Despite their close stratigraphic proximity, it is evident that the oils of the Lower Palaeozoic within the Williston Basin are distinct. This suggests the presence of a new "oil family" within the Williston Basin. Diagnostic geochemical signatures occur in the gasoline range chromatograms, within saturate fraction gas chromatograms and biomarker fingerprints. However, some of the established criteria and cross-plots that are currently used to segregate oils into distinct genetic families within the basin do not always meet with success, particularly when applied to the Lower Palaeozoic oils of the Deadwood and Winnipeg Formation.     

An Analysis of Catherine＇s Character——Wuthering Heights

Wuthering Heights, Emily Bronte＇s only novel, was published in December of 1847 under the pseudonym Ellis Bell. The book did not gain immediate success, but it is now thought one of the finest novels in the English language. Catherine is the key character of this masterpiece, because everybody and everything center on her though she had a short life. We can understand this masterpiece better if we know Catherine well.     

Features of Women's language

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.     

Characterization of Ordovician carbonate reservoirs, southeastern Saskatchewan, Canada

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.     

Design and analysis of generic LBS application developing platform

Location based services is promising due to its novel working style and contents.A software platform is proposed to provide application programs of typical location based services and support new applications developing efficiently. The analysis shows that this scheme is easy implemented, low cost and adapt to all kinds of mobile nework system.     

橡胶颗粒沥青混合料低温抗裂性试验研究

以AC-13级配为基础,将橡胶颗粒代替部分集料掺入混合料中,以低温弯曲试验为评价方法对不同橡胶颗粒掺量下沥青混合料的低温抗裂性进行研究,并引入应变能密度值对混合料的低温抗裂性进行综合评价.试验结果表明:橡胶颗粒沥青混合料试件的破坏微应变均超过2 300,满足冬寒区的技术指标;无论是否掺加橡胶颗粒,随着温度的下降,沥青混合料破坏时的最大弯拉强度增大,弯拉应变降低,劲度模量增大;弯曲应变能密度在胶粒掺量为1%左右时具有较大的弯曲应变能密度值,此时橡胶颗粒沥青混合料具有较好的低温抗裂性.     

低渗透非均质砂岩油藏启动压力梯度研究

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。     

Quantitative trait loci （QTLs） for quality traits related to protein and starch in wheat

Quality traits in wheat （Triticum aestirum L.） were studied by quantitative trait locus （QTL） analysis in a recombinant inbred line （RIL） population, a set of 131 lines derived from Chuan 35050 × Shannong 483 cross （ChSh）. Grains from RILs were assayed for 21 quality traits related to protein and starch. A total of 35 putative QTLs for 19 traits with a single QTL explaining 7.99-40.52% of phenotypic variations were detected on 10 chromosomes, 1D, 2A, 2D, 3B, 3D, 5A, 6A, 6B, 6D, and 7B. The additive effects of 30 QTLs were positive, contributed by Chuan 35050, the remaining 5 QTLs were negative with the additive effect contributed by Shannong 483. For protein traits, 15 QTLs were obtained and most of them were located on chromosomes 1 D, 3B and 6D, while 20 QTLs for starch traits were detected and most of them were located on chromosomes 3D, 6B and 7B. Only 7 QTLs for protein and starch traits were co-located in three regions on chromosomes 1D, 2A and 2D. These protein and starch trait QTLs showed a distinct distribution pattern in certain regions and chromosomes. Twenty-two QTLs were clustered in 6 regions of 5 chromosomes. Two QTL clusters for protein traits were located on chromosomes 1D and 3B, respectively, three clusters for starch traits on chromosomes 3D, 6B and 7B, and one cluster including protein and starch traits on chromosome 1D.     

On Tragic Consciousness In The Works By Ernest Hemingway

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.