动力煤的燃烧特性研究

选择了挥发分从２０％至４０％的五种典型动力煤，结合常规分析和热失重技术得到了燃煤的燃烧热失重曲线、燃烧特征温度以及动力学参数。结果表明：不同的燃烧图意味着不同的燃烧特性；燃烧特征温度（Ｔ＿１＋Ｔ＿２）／２与煤的挥发分存在一定的线性关系；五种煤的燃烧反应活化能大小顺序如下：淮北煤＞青龙山煤＞枣庄煤＞淮南煤＞柴里煤；燃烧反应可用相同的动力学模型不同的相应参数表示，ｄｘ／ｄτ＝Ａ·ｅ￣（－Ｅ／ＲＴ）·（１－ｘ）。     

利用供氢剂探讨石油渣油的热转化机理

以孤岛渣油和辽河渣油为原料、以供氢剂9，10－二氢蒽为化学探针，在反应温度360℃－430℃和体系初压为室温时4.0MPa氮气氛的热反应条件下，在微型高压釜内对渣油热转化机理随反应温度的变化进行了初步探讨。化学探针在渣油中的供氢反应遵循一级反应动力学模型；其中孤岛渣油反应体系中的供氢反应速率常数较辽河渣油中的大，并且其间的差别随温度升高而增大。虽然两种渣油反应体系中的氢转移反应积分活化能极为接近，但是微分活化能随温度升高而显著降低；这表明氢转移机理从较低温度时以分子间的反应为主转变为在较高温度时以自由基参与的反应为主。     

油页岩燃烧释放二氧化硫的本征动力学和机理

将油页岩通过酸处理和低温灰化，获得高纯度的有机质和矿物质，利用程序升温装置与二氧化硫在线分析仪，在升温速率为５℃／ｍｉｎ的条件下，分别研究了在燃烧过程中茂名油页岩及其有机质与矿物质释放二氧化硫的本征动力学。结果表明，有机硫释放二氧化硫的温度范围为２１０～４７０℃，按两段处理得到的动力学参数为：反应级数皆为１，在２１０～３４０℃，活化能Ｅ＝７６．１８ｋＪ／ｍｏｌ，频率因子Ａ＝９．９１×１０￣３ｓ￣（－１），在３４０～４７０℃，Ｅ＝１５４．７０ｋＪ／ｍｏｌ，Ａ＝７．８５×１０￣８ｓ￣（－１）ＭＰａ￣（－１）；黄铁矿硫释放二氧化硫的温度范围为２９０～５１０℃，动力学参数为Ｅ＝１９９．１０ｋＪ／ｍｏｌ，Ａ＝４．３０×１０￣（１１）ｓ￣（－１）ＭＰａ￣（－１），ｎ＝１．４。文中对油页岩中硫的燃烧转化机理进行了初步探讨。     

饱和烃促进渣油热反应初期生焦的考察

研究了石油渣油饱和烃的热裂化夺氢化学对渣油热反应体系生焦的影响,对由饱和烃－供氢探针、饱和烃－沥青质组成的二元模型反应体系,以及由饱和烃－供氢探针－沥青质组成的三元模型反应体系,分别进行高压热反应;然后关联二元反应体系和三元反应体系中饱和烃夺氢能力及供氢探针的供氢量和沥青质生焦率。结果表明饱和烃夺氢能力可促进沥青质生焦;并且饱和烃的热裂化夺氢反应性能与饱和烃的物理沉积性能相比较,前者更能促进沥青质形成凝聚相而生焦。进而测定四种减压渣油的热反应生焦趋势,发现渣油饱和分的夺氢量与渣油热反应被期的生焦趋势密切相关,而较苛刻的条件下的生焦趋势主要是由原料渣油残炭值所决定。     

渣油热反应中第二液相的形成机制

在渣油热反应体系中，随着热处理时间的延长，用光学显微镜从渣油反应品中依次观察到了片状／不规则状物理第二液相，少数圆球状化学物理第二液相和大量不规则状化学第二液相。对第二液相相分离点时渣油热反应体系物理化学状态的考察指出：物理第二兴相是渣油原始体系中的沥青质－胶质重组分混合胶团破坏后，丧失胶持组分保护的原生沥青质组分通过物理聚集过程形成的，其形貌特征源于原生沥青质组分的分形聚集过程和热力学成长过程；     

2-噻吩乙酸的低温热容和热力学性质

用精密自动绝热量热计测定了2-噻吩乙酸在78～343 K温区内的摩尔热容. 实验结果表明, 在78～314和337～343 K温区内, 该化合物无相变及其他热异常现象发生, 将实验数据拟合得到了该化合物热容随温度变化的多项式方程; 在314～337 K温区内, 该物质发生固-液熔化相变, 其熔化温度、熔化焓、熔化熵及样品纯度分别确定为: 335.745 K, 16.260 kJ•mol^－1, 48.415 J•K^－1•mol^－1和98.555%. 根据热力学函数关系式, 由热容数据计算出了2-噻吩乙酸在80～340 K温区内相对于标准参考温度298.15 K的热力学函数值.     

辽河和孤岛渣油供氢能力与生焦趋势

首先以蒽为化学探针对孤岛、辽河和胜利减压渣油及其四组分的氢转移能力进行表征,原理是,蒽与渣油在３５０～４００℃热反应,渣油向蒽供氢,使蒽转化成９,１０－二氢蒽,用气相色谱分析定量测定热反应产物中的９,１０－二氢蒽,并计算出单位重量油样供氢量;然后在４００℃下热处理测定三种渣油的生焦诱导期（定义为生焦０１％时所用时间）。结果发现：虽然它们四组分相近,但氢转移潜力相差较大,特别是它们的沥青质的氢转移能力相差悬殊;渣油热生焦诱导期长短与它们氢转移能力趋势一致     

孤岛减压渣油窄馏分的热反应动力学：——反应级数的计算

用超临界流体萃取精密分馏技术将孤岛减压渣油分成１５个窄馏分，选取其中８个在热重装置上进行了反应动力学研究。所得数据用（经本文作者改进）Ｚｓａｋｏ法进行动力学处理，计算了各窄馏分的热反应级数。结果发现，升温速率的改变对各窄馏分在同一转化率范围的反应级数影响不大，而在每一升温速率下，反应级数随反应温度和转化深度不同而改变。同时，不同升温速率下，随着转化深度的增加，各窄馏分的表观活化能升高。     

红外光谱法研究重质油分子的轻度热转化

为了从分子水平快速经济地分析重质油在热转化过程中的变化规律，利用四种模型化合物萘、四氢萘、十氢萘和正庚烷组成的混合体系来模拟重质油及其热转化缩合产物分子的基本组成，研究其红外吸收特性与平均分子参数（亚甲基和甲基的数目之比 N CH2/NCH3、芳氢率faH、芳香环系氢碳原子比NHar/NCar等）的关系。将重质油焦化重蜡油馏分进行轻度热转化，利用不同强度的系列溶剂将热转化产物的重质馏分顺序分离成系列溶剂族组分，将这些族组分进行红外分析。结果表明，混合物系列模拟体系的〖ＷＴＢＸ〗f〖ＷＴＢ１〗aH同其红外吸收在2750cm－1～3100cm－1的3000cm－1～3100cm－1强度分率（S3000~3100/S2750~3100）之间存在良好的线性关系，同时NCH2/NCH3 同2920cm－1和2960cm－1处的吸光度比值A2920/A2960之间也存在良好的线性关系。依据这些关系式可以合理解释重质油分子在热转化过程中分子结构的变化规律。随着重质油热转化的进行，NCH2/NCH3 饱和烃分子先增大后减小，芳香性族组分分子则持续降低；faH或NHar/NCar芳香性族组分分子呈现升高的趋势。     

大庆减压渣油热转化前后镍分布的研究

大庆减压渣油在高压釜中 4 0 5℃、1h条件下进行热转化反应 ,对原料及热转化后尾油 (>5 0 0℃ )用正戊烷沉淀沥青质 ,再用含水 5 % (质量分数 )的氧化铝为吸附剂的色谱法将大庆减压渣油分离为六个组分 ,然后用硅胶色谱法对每个组分中的镍卟啉进行富集 ,并根据可见光谱加以测定。用原子吸收法测定了原料减压渣油、尾油及各组分的镍含量。研究结果表明 ,大庆减压渣油经过热转化后有近 5 0 %的渣油转化为气体和馏分油 ,并有少量的焦炭生成。大庆减压渣油无戊烷沥青质 ,其中的Ni主要集中在中胶、重胶及n C5沥青质中。在热转化尾油中 ,大部分的镍集中在中胶、重胶及戊烷沥青质中 ,卟啉镍主要集中在多环芳烃和轻胶质中 ,非卟啉镍主要集中在中胶、重胶和戊烷沥青质中。热转化对镍起到了脱除作用     

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%.     

Synthesis of 1-benzyloxypyrazin-2(1H)-one derivatives

Different approaches for the synthesis of 1-benzyloxypyrazin-2(1H)-one derivatives from simple amino acids have been investigated. A library of 33 precursors for the preparation of N-hydroxy pyrazinones was obtained in moderate to good yields.     

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.     

A general and convenient synthesis of 4-(tosylmethyl)semicarbazones and their use in amidoalkylation of hydrogen,heteroatom, and carbon nucleophiles

A general synthesis of previously unknown semicarbazone-based α-amidoalkylating reagents, 4-(tosylmethyl)semicarbazones, has been developed. The synthesis involved three-component condensation of semicarbazones of aliphatic or aromatic aldehydes with the same or other aldehydes and p-toluenesulfinic acid. The scope and limitations of this reaction were investigated. The compounds obtained were demonstrated to be an efficient α-(4-semicarbazono)alkylating agents. They were reacted with H- (sodium borohydride), O- (sodium methylate), S- (sodium phenylthiolate), N- (pyrrolidine, sodium succinimide), P- (trialkyl phosphites), and C-nucleophiles (sodium diethyl malonate) to give the corresponding products of the tosyl group substitution, 4-substituted semicarbazones, including analogues of nitrofurazone. Among the prepared compounds tested in vitro for antibacterial and antifungal activity, three nitrofuryl-containing semicarbazones exhibited high biological activities with minimum inhibitory concentration (MIC) values of 8–32 μg/mL.     

Synthesis of novel chiral bidentate hydroxyalkyl-N-heterocyclic carbene ligands and their application in palladium-catalyzed Mizoroki–Heck couplings and asymmetric addition of diethylzinc to benzaldehyde

A small library of new chiral bidentate hydroxyalkyl-imidazolium salts 1 is conveniently synthesized on multi-gram scale from inexpensive and commercially available chiral pool amino acids. The corresponding carbenes, generated by deprotonation of imidazolium salts 1, in combination with palladium(II) chloride were tested in the Mizoroki–Heck coupling reaction. The most significant results in terms of yields and reactivities were achieved with low catalyst loading. The catalytic activities of these imidazolium salts were also investigated in the asymmetric addition of diethylzinc to benzaldehyde. The use of MgO nanoparticles as an additive in conjunction with these ligands played a crucial role in increasing the efficiency of these reactions.     

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%).     

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.     

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.     

Facile synthesis of bicyclic 1-arylpyrazol-5-ones

In this Letter, we described a facile method for constructing fused bicyclic 1-arylpyrazol-5-one ring system. We employed various methylene-containing carboxylic acids as the substrates and proved that the pyrazolone ring closure requires activated methylene group in intermediate II. Accordingly, a series of structurally diversified, fused bicyclic 1-arylpyrazol-5-ones was prepared in moderate to high yields using the requisite substrates.