天然气长输管线全焊接锻造球阀的密封研究

根据天然气长输管线对管线阀门密封性能可靠、耐腐蚀性、防火性以及长寿命等要求,对天然气长输管线全焊接锻造球阀的密封结构进行了研究,分别设计了双活塞效应阀座、双重密封结构和紧急救护结构,并应用密封理论给出了关键参数的设计计算公式,为天然气长输管线全焊接锻造球阀的开发与设计提供一定的理论依据。     

天津软土地区地铁运营沿线地面振动响应实测与建模分析

首先利用CMG-5TCDE一体化强震仪,对天津地铁5号线职业大学站-淮河道站区间沿线进行场地地表振动强度测试;接下来基于实际工程数据,利用ABAQUS建立轨道-道床-隧道-土层三维有限元模型,数值模型通过Py-thon程序实现黏弹性边界的设置,并应用DLOAD子程序实现列车轮载的移动施加,最终采用动力隐式分析方法模拟计...     

天津站交通枢纽轨道换乘中心地下工程防水设计

介绍了天津站交通枢纽轨道换乘中心的工程概况,结合工程具体特点对防水设计原则和设计要求进行了阐述,并对整个工程的防水体系设计进行了详细介绍.     

A review for the synthesis methods of lithium vanadium phosphate cathode materials

Monoclinic Lithium vanadium phosphate [Li₃V₂(PO₄)₃, LVP] has been extensively studied because of its attractive electrochemical properties including high specific energy, high specific capacity (133 mAh g^?1 in 3.0–4.3 V, 197 mAh g^?1 in 3.0–4.8 V), high working voltage (4.0 V), good cycle stability and low price used in rechargeable lithium ion batteries (LIBs). However, the inherent defects such as low conductivity still restrict its practical application in high performance LIBs. Various synthesis methods have been developed in order to improve electrochemical performances of LVP. The results show that the different synthesis methods have great influence on the properties of LVP cathodes for LIBs, so the study on the synthesis method of high performance LVP will continue to be in great demand. This review briefly introduces the present synthesis methods of LVP, such as high-temperature solid-state method, sol–gel method, hydrothermal method, etc. Apart from already established conventional routes, the novel preparation technologies are also mentioned. Moreover, the synthesis mechanism and electrochemical performances of Li₃V₂(PO₄)₃ cathode materials synthesized by each synthetic method are reviewed. Finally, the directions for further research and prospective applications for the LVP materials are proposed.     

疏水阀用波纹管热动力元件研究

介绍了波纹管热动力元件的热力特性及其在疏水阀的应用实例，分析了结构特点及工作原理，并总结出目前需要解决的关键问题。     

TS-1催化环己酮氨肟化反应的研究进展

钛硅分子筛TS-1是具有MFI结构的沸石分子筛,其特点为以Ti4+取代全硅分子筛骨架中的少量Si4+,使其具有独特的催化氧化性能,尤其对于有H_2O_2或有机过氧化合物参与的一系列有机物的选择氧化反应,能够使得反应具有很高的选择性。本文综述了TS-1催化环己酮氨肟化制环己酮肟反应的基础研究和工业应用现状及存在的问题,并对其今后的研究及应用作了展望。     

人工砂磨粉掺粉工艺技术的应用

以万家口子水电站工程为背景,介绍了在已建人工砂石系统中增加磨粉掺粉工艺,实施在线磨粉掺粉的方案和技术措施,使人工砂含粉率满足了大坝碾压混凝土施工所需16%~20%的标准要求。     

Lithium Azides Induced SnS Quantum Dots for Ultra-Fast and Long-Term Sodium Storage

Tin sulfide (SnS) is an attractive anode for sodium ion batteries (NIBs) because of its high theoretical capacity, while it seriously suffers from the inherently poor conductivity and huge volume variation during the cycling process, leading to inferior lifespan. To intrinsically maximize the sodium storage of SnS, herein, lithium azides (LiN₃)-induced SnS quantum dots (QDs) are first reported using a simple electrospinning strategy, where SnS QDs are uniformly distributed in the carbon fibers. Taking the advantage of LiN₃, which can effectively prevent the growth of crystal nuclei during the thermal treatment, the well-dispersed SnS QDs performs superior Na⁺ transfer kinetics and pseudocapacitive when used as an anode material for NIBs. The 3D SnS quantum dots embedded uniformly in N-doped nanofibers (SnS QDs@NCF) electrodes display superior long cycling life-span (484.6 mAh g⁻¹ after 5800 cycles at 2 A g⁻¹ and 430.9 mAh g⁻¹ after 7880 cycles at 10 A g⁻¹), as well as excellent rate capability (422.3 mAh g⁻¹ at 20 A g⁻¹). This fabrication of transition metal sulfides QDs composites provide a feasible strategy to develop NIBs with long life-span and superior rate capability to pave its practical implementation.     

利用测井资料进行生油岩评价——以王46井生油岩评价为例

介绍了生油岩的测井响应特征以及生油岩定性和定量评价方法。利用测井资料评价生油岩的依据是生油岩在不同测井曲线上的响应特征。采用自然伽马能谱测井定性识别生油岩，利用声波法和电阻率法定量计算生油岩参数，根据岩心分析的有机碳含量与铀、钍、钾的关系回归计算评价生油岩等多种方法，对王46井孔店组地层生油岩进行定性和定量评价，并结合岩心分析资料确定出王46井孔店组有机质的丰度、有机质成熟度和有机质类型等。最后依据岩心分析资料，对不同计算方法的计算结果进行误差对比分析，证明了利用测井资料对该井生油岩评价的可靠性。     

区域自适应的图像修复算法

针对Criminisi等人提出的基于样本的图像修复算法使用穷尽搜索的方式寻找最优匹配像素块,以及采用固定大小的修复像素块进行修复时产生的错误匹配和信息延伸对图像修复质量的影响,根据像素点周围邻域信息对该像素点的决定作用和结构信息的重要性,提出一种区域搜索和自适应模板图像修复方法,以增强信息的局部协调性和边界信息的恢复能力,提高图像整体的修复效果。大量实验表明,改进算法在减少修复时间的同时,能较好地保持图像的结构,从而使修复结果达到更好的视觉效果。