一段转化炉竖琴管排吊簧改造及调整

针对一段蒸汽转化炉厚壁型炉管(HK-40)改薄壁型炉管(HP-Nb+M)后,因单根炉管重量减少近30%,受压恒力吊簧无调节功能,不能满足新载荷工况下的使用要求问题,于1996年和2007年两次对弹簧K(弹性系数)值进行校验。鉴于校验值与设计值无明显变化,弹簧特性还处于良好状态,从降低设备改造成本考虑,对竖琴管排承重吊簧进行改造使用,由新核定的工作载荷确定新工况下A、B吊簧改造后的冷态"O"值,并确定管排安装方法和吊簧的冷、热态调整要求。     

埃索美拉唑钠的波谱学数据和结构确证

建立利用分析仪器确证埃索美拉唑钠化学结构的方法。利用UV、IR、NMR、MS对埃索美拉唑钠进行了结构分析。对埃索美拉唑钠的红外吸收光谱(IR)、核磁共振氢谱(1H NMR)、氢-氢相关谱(1H-1H COSY)、核磁共振碳谱13C NMR、DEPT谱、碳氢相关谱(HMQC)、碳氢远程相关谱(HMBC)及质谱(MS)进行了解析,对其所有的NMR谱信号进行了归属;讨论了红外光谱特征吸收峰所对应的官能团的振动形式,确证了埃索美拉唑钠的结构为S-5-甲氧基-2-{[(4-甲氧基-3,5-二甲基-2-吡啶基)甲基]亚磺酰基}-1H-苯并咪唑钠。本研究为埃索美拉唑钠的结构鉴定提供了依据。     

设计性实验教学体系在医用《基础化学》课程中的构建

在医用基础化学课程中,构建完善合理的设计性实验教学体系,是培养医学类创新型人才的有效途径。文章详细论述设计性实验教学体系构建的一般原则和步骤,并指出教学实践中具体实施时存在的问题,为设计性实验教育教学改革提供参考。     

广东石油分公司天然气加气业务发展战略研究

世界各国面临气候变化的挑战,人们将目光投向最清洁的化石能源——天然气。天然气也是汽车理想的替代燃料,以开拓天然气零售和直分销业务作为燃气业务拓展主攻方向,抢占先机积极推进天然气加气网点建设投营和天然气直分销业务,快速提高天然气市场占有率已成为广东石油的发展战略。     

Metal‐Free Autoxidative Nitrooxylation of Alkenyl Oximes with Molecular Oxygen

A metal‐free aerobic autoxidative nitrooxylation of alkenyl oximes mediated by tert‐butyl nitrite is described. Molecular oxygen is used as the oxidizing reagent, avoiding use of organic trapping reagents such as 2,2,6,6‐tetramethylpiperidine 1‐oxyl (TEMPO). The desired products were obtained in generally high yields.

     

Enhanced mechanical,thermal and dielectric properties of polyimide nanocomposites containing SiCp (SiCw) nanofillers for high energy-storage applications

Journal of Polymer Research - In this paper, we aimed to develop the nanocarrier based on poly (N-isopropyl acrylamide)—allyl acetoacetate grafted MoS2 nanosheets. The obtained polymer...     

Preparation of lightweight and hydrophobic natural biomass-based carbon aerogels for adsorption oils and organic solvents

Journal of Porous Materials - In the present work, an excellent carbon aerogel (PCA) with low density, hydrophobicity and porous structure has been successfully prepared by hydrothermal...     

Numerical modeling of the 2008 Wenchuan earthquake-triggered Niumiangou landslide considering effects of pore-water pressure

Bulletin of Engineering Geology and the Environment - Ring-shear experiments are commonly conducted to analyze the kinematic mechanisms of landslides triggered by earthquakes, particularly for...     

Analysis of stress evolution characteristics during TBM excavation in deep buried tunnels

Bulletin of Engineering Geology and the Environment - Full-face tunnel boring machines (TBMs) are widely used in tunnel engineering projects as an efficient, safe and economical tunneling method....     

Rapid Carbonation for Calcite from a Solid-Liquid-Gas System with an Imidazolium-Based Ionic Liquid

Aqueous carbonation of Ca(OH)₂ is a complex process that produces calcite with scalenohedral calcite phases and characterized by inadequate carbonate species for effective carbonation due to the poor dissolution of CO₂ in water. Consequently, we report a solid-liquid-gas carbonation system with an ionic liquid (IL), 1-butyl-3-methylimidazolium bromide, in view of enhancing the reaction of CO₂ with Ca(OH)₂. The use of the IL increased the solubility of CO₂ in the aqueous environment and enhanced the transport of the reactive species (Ca²⁺ and CO₃²⁻) and products. The presence of the IL also avoided the formation of the CaCO₃ protective and passivation layer and ensured high carbonation yields, as well as the production of stoichiometric rhombohedral calcite phases in a short time.