多组分气固射流床流动特性 Ⅱ流型的划分

在３００×５０×２６００ｍｍ的二维射流流化床中,使用压力波动的功率谱分析方法,考察了９种单一、双组分混合物物性因素（粒径、密度）、操作因素（射流气速、喷口直径、静床高度、环隙气量）对射流流化床的三种流型：气泡串、射流、喷流相互转变的影响。结果表明,在较低静床高时,随着射流气速的增大,射流床内流型由气泡串、射流过渡到喷流;而静床高较高时,射流气速增大仅由气泡串过渡到射流。环隙气量增大、粒径增大、密度增大,喷流流型出现较困难,最后得出了流型转变图及转变的定量关系式     

双射流流化床流动特性的研究

在一300×2600mm二维双射流流化床中,采用多路压力信号采集装置,详细研究了射流气速、射流喷口管间距离、静床高度、物性参数对双射流流化床射流流动特性的影响,发现双射流从单独存在到两射流在其射流区内发生射流合并可由压力波动时间序列的功率谱主频和Hurst指数的变化定量确定,结果还表明,双射流流化床管间距减小时,射流在射流区发生合并的射流气速降低;而管间距相同时,静床高变大,射流在射流区发生合并的射流气速也降低;对于相同粒径的固体颗粒,颗粒密度增大使得射流在射流区发生合并的射流气速变大。     

多组分气固射流床流动特性：Ⅱ.流型的划分

在３００＊５０＊２６００ｍｍ的二维射流流化床中,使用压力流动的功率谱分析方法,考察了９种单一,双组分混合物物性因素,操作因素对射流流化床的三种流型：气泡串、射流、喷流相互转变的影响。     

加压流化床流化性质的实验与模拟研究

在二维射流流化床装置中,考察了压力对颗粒和气泡运动的影响规律.通过使用摄像技术详细的记录了压力下气泡的行为,并对其进行了分析,由此解决了较高压力下测量流态化性质较为困难的问题.数值研究通过CFD双欧拉模型模拟了带有V形分布器和中心射流的二维流化床内压力对气泡大小、床的膨胀率和射流深度的影响.实验和理论结果表明,在加压状态下,射流气速和分布板气速对气泡的产生、大小及形状有不同的影响.在较高的操作压力下,射流气速增加,气泡变长;分布器气速增大,气泡则变大;射流高度随着分布器气速的增加而降低.模拟结果与实验数据吻合较好,由此该模型为研究较高操作压力下射流流化床流化性质提供了有利的工具.     

灰熔聚射流流化床适宜操作条件及几何结构

在３００×５０×２６００ｍｍ带有流化分离柱的灰熔聚冷模流化床中，选用具有实际意义的焦粉／灰球体系，通过考察不同操作条件及不同几何结构时灰球的分离效率及分离速率的变化特征，以确定这一射流流床的适宜操作及几何条件。证明了对分离操作而言，射流分离分隔式的流化床具有操作弹性大的优点。基于实验结果及理论分析，指出流出分离柱高／宽比小于３．７时可获得稳定分离操作，并给出分离柱高效分离操作时的气速变化范围。本文     

多组分气固射流床流动特性：Ⅰ.压力波动的测试装置与数据处理方法

开发了一套具有多路循环，现场显示功能的压力测试装置。在３００×５０ｍｍ二维气固射流床中采用多组分混合物，对带有喷口的气固流化床的三种流型：气泡串、射流、喷流进行了分段功率谱、压力波动的直方图和概率统计分析的研究。并报导了混合物的功率谱密度图及直方图。     

射流携带床反应器液体停留时间分布及模拟

对射流携带床液体停留时间分布进行了研究，考察了液体流量、气体流量和气体动量对液体停留时间分布的影响。结果表明，增加液体流量使停留时间分布密度曲线变得高而窄，且平均停留时间变短；气体流量增大使得停留时间出峰略有提前，气体流量大于4L/min时，继续增大气体流量对液体停留时间分布影响较小；当液体流量小于60L/h时，气体动量对液体停留时间的影响较明显，主要表现气体动量越大液体平均停留时间越长。基于实验结果分析及实验中观测的现象，将射流携带床内液体流动结构分为中心区和壁面区进行研究，建立了描述射流携带床内液体停留时间分布的数学模型，模型模拟结果和实验数据吻合良好。     

双组分冷模射流流化床气化炉内流体动力学特性模拟

针对实际工业生产中经常遇到的多组分体系，本文选取了具有代表性意义的非等密度/直径的双组分体系(树脂和砂子)为研究对象，以Goossens等提出的平均物性法则计算了固体混合物的平均粒径和平均密度，采用欧拉－欧拉计算流体动力学模型(CFD)模拟了二维冷模射流床气化炉内，诸如气、固相流场的时空分布、时均空隙率分布、射流穿透深度等流体动力学的时空特征，所得结果与文献报道相吻合。     

气-固流化床反应器内双流体力学模型及其验证Ⅲ.单组分两维射流床内射流特性

在湍流两相流理论建立的双流体力学模型基础上，编写了模拟气、固相流体动力学的ＣＡＳＩＣＣ软件包。本文详细地分析了射流流化床内射流（或气泡）边界的确定方法，模拟了不同操作条件下的射流穿透深度和射流频率，所得结果与前人的经验关联式相吻合。证明了该方法可用来预测灰熔聚粉煤气化及其它与射流床相关工艺的射流特性。     

气固流化床内射流特性的研究

采用Brandani等的数学模型模拟了中心射流宽度为0.01m的二维气固流化床(高1.6m、宽0.3m)内鼓泡和射流的瞬态及时均流体动力学特性。一种典型的Geldart B颗粒――砂子(粒径为500mm、密度为2660kg/m3)作为研究的模拟物料。瞬态结果表明，床内射流产生和发展、射流崩塌后所形成气泡尺寸以及全床内的气体速度场和空隙率均存在明显的非对称性，但是由压力信号功率谱密度得到的时均压力特性则有较好的对称性。因此，对于商业化稳定运转的射流床，可以用半床模拟结果近似解释整床特性；然而，在考察射流床的瞬态特性时，半床模拟结果与整床结果存在明显偏差。     

二氧化碳和丙烯直接合成甲基丙烯酸的NiPMo/TiO2催化剂的研究

用溶胶-凝胶法以磷钼酸(MPA)的镍盐溶液水解钛酸四丁酯制备了NiPMo/TiO2催化剂.使用ICP、 XRD、 TG-DTA、 IR、 TPD-MS和微反应技术研究了催化剂的化学组成、热稳定性、化学吸附性质和催化反应性能.杂多钼酸盐与TiO2通过O2-在TiO2表面发生了键合.在623 K下,杂多阴离子仍保持原有的Keggin结构.CO2在Lewis酸位Ni(Ⅱ)和Lewis碱位Ni-O-Mo的桥氧协同作用下生成CO2卧式吸附态Ni(Ⅱ)←O-(CO)←(O--Ni).丙烯有多种吸附态在催化剂上吸附.在563 K、 1 MPa和空速1500 h-1的反应条件下,丙烯的摩尔转化率为3.2%,产物MAA选择性为95%.     

Toward new camptothecins. Part 6: Synthesis of crucial ketones and their use in Friedländer reaction

In the context of the preparation of camptothecin and luotonin A analogs, the synthesis of some key keto-precursors and their use in Friedländer condensation are described. This paper also focuses on the stability of these keto intermediates and emphasizes the major differences between indolizinones and pyrroloquinazolinones series. Noteworthy is also the report of some original structures isolated as by-products of some experiments.     

α-Amino acid derived enaminones and their application in the synthesis of N-protected methyl 5-substituted-4-hydroxypyrrole-3-carboxylates and other heterocycles

A new and simple synthesis of novel N-protected methyl 5-substituted-4-hydroxypyrrole-3-carboxylates, which exist in equilibrium with their 4-oxo tautomers, has been developed in two steps starting from N-protected α-amino acids. The key intermediates are enaminones, which can also be isolated, characterized, and used for the construction of other functionalized heterocycles, before they spontaneously decompose to pyrrole products. 4-Hydroxypyrroles are prone to partial aerial oxidation but can be efficiently alkylated or reduced to stable polysubstituted pyrrolidine derivatives.     

Specific intramolecular aromatic CH insertion of diazosulfonamides

The chemoselectivity in the intramolecular CH insertion of various diazosulfonamides has been experimentally studied. The results reveal that the aliphatic 1,4-, 1,5-, or 1,6-C(sp³)?H insertions of diazosulfonamides are not accessible, while the aromatic 1,5-C(sp²)?H insertion can be realized specifically by adjusting the diazo-adjacent group. In addition, the general chemoselectivities in the intramolecular CH insertions of diazosulfonyl compounds are summarized. Generally, diazosulfones undergo both aromatic 1,5-C(sp²)?H and aliphatic 1,5- and 1,6-C(sp³)?H insertions, while diazosulfonates undergo aliphatic 1,5- and 1,6-C(sp³)?H insertions. However, diazosulfonamides only undergo aromatic 1,5-C(sp²)?H insertion.     

CoFe2O4自形成磁性液体场致结构化对磁化的影响

The Langevin paramagnetic theory can’t describe the relation between magnetization of ferrofluids and applied magnetic field. The structuralization of ferrofluids, which is considered the main influence factor of the magnetization, is regarded. The part of magnetization works is deposited when the structure is forming. This action influences the magnetization of ferrofluids directly or indirectly. On the base of the “compressing” model, the Langevin function that usually describes the magnetization of ferrofluid is modified, and a well-fitted curve is obtained. An equation of the relation between the equivalent volume fraction after being “compressed” and the intensity of magnetic field is discovered, which approximately describes the process of magnetization. The relation between the approximate initial susceptibility and the volume fraction can be obtained from modified formula.     

KMnO4-mediated oxidative CN bond cleavage of tertiary amines: Synthesis of amides and sulfonamides

KMnO₄-mediated oxidative CN bond cleavage of tertiary amines producing secondary amine was introduced, which was trapped by electrophiles (acyl chloride and sulfonyl chloride) to form amides and sulfonamides. The reaction could take place at mild condition, tolerating a wide range of function groups and affording products in moderate to excellent yields.     

Chemistry of heterocyclic compounds at the A. E. Favorsky Irkutsk Institute of Chemistry, Siberian Branch of the Russian Academy of Sciences, over 50 years (Review)

The review contains a concise historical account and information on the most significant researches undertaken by the staff at the A. E. Favorsky Irkutsk Institute of Chemistry, Siberian Branch of the Russian Academy of Sciences on the Chemistry of Heterocyclic Compounds. Dedicated to Academician of the Russian Academy of Sciences B. A. Trofimov on his 70th jubilee. Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 10, pp. 1443–1502, October, 2008.     

Highly regioselective Buchwald–Hartwig amination at C-2 of 2,4-dichloropyridine enabling a novel approach to 2,4-bisanilinopyridine (BAPyd) libraries

The highly regioselective Buchwald–Hartwig amination at C-2 of the cheap and readily accessible reagent, 2,4-dichloropyridine with a range of anilines and heterocyclic amines is described. This new methodology is robust and provides a facile access to 4-chloro-N-phenylpyridin-2-amines on 0.25 mol scale. These intermediates undergo a further Buchwald–Hartwig amination at higher temperature to enable rapid exploration of the chemical space at C-4 and to provide a library of 2,4-bisaminopyridines.     

N-Heterocyclic carbene-palladacyclic complexes: synthesis,characterization and their applications in the C-N coupling and α-arylation of ketones using aryl chlorides

N-Heterocyclic carbene-palladacyclic complexes 3 were successfully achieved in a one-pot procedure under mild conditions. The structure of 3a was unambiguously confirmed by X-ray single crystal diffraction and it was an active catalyst in the Buchwald-Hartwig amination and α-arylation of ketones even at very low catalyst loadings (0.01?mol%).     

Iodine-mediated oxidative Pictet-Spengler reaction using terminal alkyne as the 2-oxoaldehyde surrogate for the synthesis of 1-aroyl-β-carbolines and fused-nitrogen heterocycles

An efficient iodine-mediated oxidative Pictet-Spengler reaction in dimethyl sulphoxide (DMSO) using terminal alkynes as the 2-oxoaldehyde surrogate for the synthesis of aryl (9H-pyrido[3,4-b]indol-1-yl)methanones is described. The scope of the protocol includes the total synthesis of Fascaplysin, Eudistomins Y₁ and Y₂. The methodology is extended for preparing pyrrolo[1,2-a]-quinoxaline and indolo[1,5-a]quinoxaline derivatives. The utility of 1-aroyl-β-carbolines was demonstrated by performing palladium-catalyzed β-carboline directed ortho-C(sp2)-H functionalization of the phenyl ring with thiomethyl (SMe) group using DMSO as source and for accessing 4-aryl-canthin-6-ones.