原位担载Fe2S3催化剂煤的热解动力学研究

用加压热天平研究了原位担载纳米级Fe2S3催化剂的大柳塔次烟煤的加氢热解动力学,考查了2.0MPa氢气氛或氮气氛下原煤及担载催化剂的煤热解失重过程,计算了活化能E和指前因子A等热解动力学参数。结果表明,煤原位担载Fe2S3催化剂后热失重速率比原煤有较大程度的增加,最大热解速率的特征温度也比原煤降低。特别是煤在表面性剂十六烷基三甲基溴化铵溶液中担载Fe2S3催化剂后的热解反应速率高于水溶液中担载同样催化剂的热解反应速度。原位担载Fe2S3的煤及原煤的热解反应过程符合一级反应动力学。     

繁峙煤镜质组的生烃特征与热解产物生成动力学研究

本文利用付立叶红外光谱（ＦＴＩＲ），热解气相色谱（Ｐｙ－ＧＣ）及热解气相色谱质谱（Ｐｙ－ＧＣ－ＭＳ）联用技术等分析手段，探讨了我国山西繁峙煤镜质组的生烃特征，鉴定了如气体烃、正构脂肪烃、苯酚、单环芳烃以及甲氧基酚类等热解产物６７种化合物。用相继等温热解法一级反应动力学模型，求取了热解产物如气体组分（Ｃ１￣Ｃ６）、轻烃（Ｃ７￣Ｃ１４）、重烃（Ｃ１５￣Ｃ３０）、正构脂肪烃（ｎＣｉ）、烷基芳烃、苯酚等的     

原位担载Fe_2S_3催化剂煤的热解动力学研究

用加压热天平研究了原位担载纳米级Fe2 S3 催化剂的大柳塔次烟煤的加氢热解动力学 ,考查了 2 0MPa氢气氛或氮气氛下原煤及担载催化剂的煤热解失重过程 ,计算了活化能E和指前因子A等热解动力学参数。结果表明 ,煤原位担载Fe2 S3 催化剂后热失重速率比原煤有较大程度的增加 ,最大热解速率的特征温度也比原煤降低。特别是煤在表面活性剂十六烷基三甲基溴化铵溶液中担载Fe2 S3 催化剂后的热解反应速率高于水溶液中担载同样催化剂的热解反应速度。原位担载Fe2 S3 的煤及原煤的热解反应过程符合一级反应动力学。     

RE(Hsal)2·(tch)·2H2O配合物与大肠杆菌作用的热动力学研究

用TAMair微量热仪测定了新合成的稀土水杨酸硫代脯氨酸配合物RE(Hsal)2·(tch)·2H2O(RE=La,Sm;Hsal=C7H5O3;tch=C4H6NO2S)在37.00℃时对大肠杆菌作用的产热曲线;根据产热曲线计算了在稀土水杨酸硫代脯氨酸配合物作用下,大肠杆菌生长代谢的最大发热功率Pmax、速率常数k、传代时间tG、抑制率I和半抑制浓度cI,50等热动力学参数.结果表明:稀土水杨酸硫代脯氨酸配合物在低浓度下对大肠杆菌有刺激作用,高浓度下为抑制作用,即稀土配合物对微生物的生长具有双向生物效应,也称为Hormesis效应.配合物Sm(Hsal)2·(tch)·2H2O(cI,50=1.62mg·L-1)的抑制效果优于La(Hsal)2·(tch)·2H2O(cI,50=7.60mg·L-1).     

RE(Hsal)2•(tch)•2H2O配合物与大肠杆菌作用的热动力学研究

用TAM air微量热仪测定了新合成的稀土水杨酸硫代脯氨酸配合物RE(Hsal)2•(tch)•2H2O (RE＝La, Sm; Hsal＝C7H5O3; tch＝C4H6NO2S)在37.00 ℃时对大肠杆菌作用的产热曲线; 根据产热曲线求算了在稀土水杨酸硫代脯氨酸配合物作用下, 大肠杆菌生长代谢的最大发热功率Pmax、速率常数k、传代时间tG、抑制率I和半抑制浓度cI,50等热动力学参数. 结果表明: 稀土水杨酸硫代脯氨酸配合物在低浓度下对大肠杆菌有刺激作用, 高浓度下为抑制作用, 即稀土配合物对微生物的生长具有双向生物效应, 也称为Hormesis效应. 配合物La(Hsal)2•(tch)•2H2O和Sm(Hsal)2•(tch)•2H2O的半抑制浓度cI,50分别为7.60和1.62 mg•L－1. 即配合物Sm(Hsal)2•(tch)•2H2O的抑制效果优于La(Hsal)2•(tch)•2H2O.     

Hydrogen Bonds in Coal -The Influence of Coal Rank and the Recognition of a New Hydrogen Bond in Coal

By means of in-situ diffuse reflectance FTIR.The IR spectra of 6 coals with different ranks were obtained from room temperature to 230℃.A new curve fitting method was used to recognize the different hydrogen bonds in the coals.and the influence of coal ranks on the distribution of hydrogen bonds(HBs) in the coals and their thermal stability were discussed.The results show that there is another new HB(around 2514cm^-1) between the-SH in mercaptans or thiophenols and the nitrogen in the pyridine-like compounds in the coals.and the evidence for that was provided.The controversial band of the HB between hydroxyl and the nitrogen of the pyridine-like compounds was determined in the range of 3028-2984cm^-1,and the result is comsistent with but more specific than that of Painter et al.It was ound that the stability of different HBs in the coals is influenced by both coal rank and temperature,For some HBs.the higher the coal rank,the higher the stability of them.Within the temperature range of our research,the stability of the HB between the hydroxyl and the π bond increases to some extent for some coals at temperatures higher than 110 or 140℃.     

煤热解过程中气态硫及气态烃逸出的同步在线分析

建立了一种简单的在线同时检测煤热解过程中气态硫及烃类选出的方法-TPD-FPD＆FID。检测装置由可实现程序升温的微型热解反应器(TPD)、在线的火焰光度检测器和火焰离子化检测器(FPD)及数据采集系统构成，数据处理方法简单。应用此方法对神木煤进行了分析，得到了其气态硫及烃类选出的动态特征。并通过对比实验验证了此方法的准确性及重复性。     

Kinetics of the Reaction of Abstracting Hydrogen from Ethylene by Hydrogen Atom

Hydrogen abstraction reaction, H C2H4 --H2 C2H2 was studied by using A initio SCF method. Ge-ometries were fully optimized at SCF level and energies were computed at STO-3G basis set for reactants and transition state. Vibrational analysis was performed thereupon. Finally, the rate constant calculations were carried out at different temperatures for all range of reaction temperature according to Eyring's sbwlute reaction rate theory. The calculated activation energy is 12. 68 kcal/mol, lower than observed value (H. S kcal/mol) by 1. 82 kcal/mol only. The agreement of the calculated rate constants with the experiments is satisfactory.     

Influences of Temperature and Coal Particle Size on the Flash Pyrolysis of Coal in a Fast-entrained Bed

IntroductionCoal is the major primary energy source in China,which accounts for about three quarters of the total en-ergy consumption.Most of coal in China contains a rel-atively high content of volatile substances.The reserveof lignite accounts for about…     

应用分布活化能模型分析伊敏褐煤丝炭腐植酸热解及氢气生成动力学

应用开放体系的热重-质谱(TG-MS)联用技术在5、20和50℃·min-1三个升温速率下对伊敏褐煤丝炭腐植酸(F-HA)和脱灰丝炭腐植酸(DF-HA)的热解行为进行了分析,并利用分布活化能模型(DAEM)分别对其热解和氢气生成动力学进行分析,获得了热解过程和氢气生成的活化能分布函数.结果表明:(1)F-HA热解活化能分布函数呈类Gaussian分布,且具有一定的对称性,主峰位与标准Gaussian分布相一致;DF-HA热解活化能分布函数也呈类Gaussian分布形式,主峰位与Gaussian分布相比,偏向低活化能值.根据转化率与温度、活化能的关系,结合腐植酸的热失重特征,将F-HA热解过程划分为四个阶段,DF-HA热解过程划分为五个阶段,并对腐植酸热解过程中各阶段的化学反应进行了详细讨论.(2)F-HA和DF-HA热解氢气生成活化能分布函数均呈类Gaussian分布,热解氢气生成活化能的整体趋势为随着转化率的升高而增加,但也表现出一定的阶段集中分布特征.根据热解氢气生成的动力学特征,将其生成过程划分为五个阶段,反映了其生成的不同化学反应机制.(3)酸洗脱灰对伊敏丝炭提取出的HA的热解行为、热解过程及热解氢气生成动力学产生了影响.     

电化学法制备Ni-W-P纳米线阵列电极及其催化析氢性能

采用二次氧化法制备了多孔阳极氧化铝(AAO)模板, 通过控制电位沉积技术在AAO模板内组装了Ni-W-P合金纳米线阵列. 在扫描电子显微镜(SEM)下观察到Ni-W-P纳米线表面光滑, 长约20 μm, 直径均匀(约为100 nm), 与AAO模板孔径基本一致. 阴极极化曲线和交流阻抗图谱(EIS)的测试结果表明, Ni-W-P合金纳米线阵列电极析氢反应(HER)电阻减小, 具有更高的催化析氢活性, 电流密度为10 mA·cm^-2时, 析氢极化电位较Ni-W-P合金电极正移约250 mV.     

霍林河褐煤热解甲烷生成反应类型及动力学的热重-质谱实验与量子化学计算

应用开放体系的热重-质谱联用技术(TG/MS)对未成熟的霍林河褐煤(镜质组最大反射率ROmax为0.33%)进行了热解模拟, 获得了甲烷的在线析出速率曲线. 曲线拟合结果表明, 甲烷生成速率曲线可以分解为5个峰, 结合化学动力学分析, 发现低温阶段甲烷的峰为吸附甲烷析出峰, 其余四个峰为热解甲烷的生成峰, 代表四类不同的化学反应. 将煤的结构特征及量子化学的理论计算相结合, 认为甲烷的生成包括4类反应, 类型1为与氧等杂原子相连的脂碳断裂; 类型2包含了两种反应, 一种是短链脂肪烃类官能团β位断裂, 另一种是所形成的长链脂肪烃类物质二次裂解; 类型3是与芳核直接相连的甲基热解脱落; 类型4为存在于煤结构中脂肪类物质的芳香化.     

One-Step Template/Solvent-Free Pyrolysis for In Situ Immobilization of CoP Nanoparticles onto N and P Co-Doped Carbon Porous Nanosheets towards High-efficiency Electrocatalytic Hydrogen Evolution

The search for economical, active and stable electrocatalysts towards the hydrogen evolution reaction (HER) is highly imperative for the progression of water electrolysis technology and related sustainable energy conversion technologies. The delicate optimization of chemical composition and architectural configuration is paramount to design high-efficiency non-precious metal HER electrocatalysts. Herein, we report a one-step scalable template/solvent-free pyrolysis approach for in situ immobilizing uniform CoP nanoparticles onto N and P co-doped carbon porous nanosheets (denoted as CoP@N,P-CNSs hereafter). The simultaneous consideration of architectural design and nanocarbon hybridization renders the formed CoP@N,P-CNSs with plentiful well-dispersed anchored active sites, shortened pathway for mass diffusion, enhanced electric conductivity, and reinforced mechanical stability. As a consequence, the optimized CoP@N,P-CNSs exhibit an overpotential of 115 mV to afford a current density of 10 mA cm⁻², small Tafel slope of 74.2 mV dec⁻¹, high Faradaic efficiency of nearly 100 %, and superb long-term durability in an alkaline medium. Given the fabrication feasibility, mass production potential and outstanding HER performance, the CoP@N,P-CNSs may hold great promise for large-scale electrochemical water splitting. More importantly, the explored one-step template/solvent-free pyrolysis methodology offers a feasible and versatile route to fabricate carbon nanosheet-based nanocomposites for diverse energy conversation-related applications.     

镍锡析氢活性阴极的电化学制备及其在碱性溶液中的电催化机理

采用恒电流电沉积法在铜箔基底上获得镍锡合金镀层电极. 电子能谱(EDS)、X射线衍射(XRD)以及高分辨透射电镜(HRTEM)分析表明, 随着锡含量的增加, 镀层由镍晶胚与非晶镍锡构成的非晶态结构转变为Ni₃Sn₄与Ni₃Sn₂的混晶结构. 扫描电镜(SEM)分析发现, 非晶结构镍锡合金电极表面粒子分布均匀且粒径细小, Ni₃Sn₄与Ni₃Sn₂混晶结构的镍锡合金电极表面粗糙且断面呈分层自组装结构. 在25℃, 1 mol·L^-1 NaOH溶液中的稳态极化曲线表明非晶结构的镍锡合金电极具有良好的催化活性, 其析氢过电位仅为85 mV. 交流阻抗测试表明, 非晶以及混晶结构的镍锡合金在析氢电催化反应过程中由电化学吸附(Volmer)以及电化学脱附(Heyrovsky) 两个电荷转移过程控制, 且非晶结构电极相比于Ni₃Sn₄与Ni₃Sn₂混晶结构电极的高活性源于其活性氢具有更快的电化学吸附以及脱附速度.     

Fabrication of Ni Nanoclusters-Modified Brookite TiO2 Quasi Nanocubes and Its Photocatalytic Hydrogen Evolution Performance

The development of low-cost, earth-abundant and highly-efficient cocatalysts is still important to promote the photocatalytic H₂ evolution reaction over semiconductors. Herein, a series of Ni nanoclusters (NCs) modified brookite TiO₂ quasi nanocubes (BTN) (marked as Ni/BTN) are fabricated via a chemical reduction process. It is found that the loading content and oxidation state of Ni NCs can significantly influence the optical absorption, photocat-alytic activity, and stability of Ni/BTN composites. Among the resultant Ni NCs-loaded products, 0.1%Ni/BTN composite delivers the best H₂ evolution activity (156 μmol/h), which is 4.3 times higher than that of the BTN alone (36 μmol/h). Furthermore, the Ni NCs with ultra ne size (∽2 nm) and high dispersity enable shorter charge transfer distance by quickly capturing the photoexcited electrons of BTN, and thus result in the improved activity even though the oxidization of some Ni NCs on BTN is harmful to the activity for H₂ evolution due to the much lower electron capturing capability of NiO than metallic Ni. This study not only clari es that brookite TiO₂ would be a promising high-efficient photo-catalyst for H₂ evolution, but also reveals vital clues for further improving its photocatalytic performance using low-cost Ni-based cocatalyst.