五年来李大钊研究综述

李大钊同志是中国最早的马克思主义者,他在社会科学的许多领域为后人留下了丰富的理论遗产。因此,李大钊一直是学术界研究的重点人物。近五年来,李大钊的研究取得了长足的进步,出现了一大批新的研究成果,使李大钊研究呈现出新的特点。第一,研究的领域不断拓宽,研究的问题进一步细化,并且切入问题的角度比较新颖。第二,尝试以新的立论基础探讨学术界争论已久的问题,不断使老课题焕发出新意。第三,注重还原李大钊生活的时代背景,以便能更好地把握其思想发展的整体脉络。第四,研究的时代感增强,凸亘出李大钊思想对于当代中国现代化建设的重大意义。     

Journal of Mathematical Research with Applications Guide for Authors

正Journal overview:Journal of Mathematical Research with Applications(JMRA),formerly Journal of Mathematical Research and Exposition(JMRE)created in 1981,one of the transactions of China Society for Industrial and Applied Mathematics,is a home for original research papers of the highest quality in all areas of mathematics with applications.The target audience comprises:pure and applied mathematicians,graduate students in broad fields of sciences and technology,scientists and engineers interested in mathematics.     

A guide for proper utilisation of stable isotope reference materials*

Many scientific publications about stable isotope ratios suffer from flawed practices regarding calibration and normalisation of raw δ values in conjunction with prescribed δ values of reference materials. Violations of the identical treatment principle with regards to samples and standards (i.e. reference materials) and lack of adherence to SI-mandated and IUPAC-recommended nomenclature exacerbate the widespread problem of lackadaisical analytical practice and reporting. Science is supposed to strive for exactness, whereas ambiguity and jargon confound interdisciplinary communication. This contribution aims to expose typical misconceptions and avoidable errors and offers guidance toward the reproducible generation of isotope data, isotopic scale normalisation, and proper data reporting. We offer a comprehensive overview of sources of light stable isotope reference materials to best match sample matrices encountered by stable isotope practitioners with chemically similar reference materials.     

Optical spectroscopy studies on FeTe_(1-x)Se_x and A_xFe_(2-y)Se_2 (A=K,Rb, Cs): A brief overview

In this short overview, we summarize the optical spectroscopy studies on iron selenide superconducting systems FeTe1-xSex and AxFe2-ySe2 . We elaborate that optical spectroscopy measurements yield fruitful information about the band structure evolution across the AFM phase transition temperature, the electronic correlation effect, the superconducting pairing energy gap, the condensed carrier density or penetration depth, the inhomogeneity and the nanoscale phase separation between superconductivity and antiferromagnetism in those systems.     

向量优化及其若干进展

在一定的约束条件下极小化或极大化向量值函数,这就是向量优化. 向量优化是数学规划学科中的重要分支学科,是具有重要应用价值的、新兴的和多学科交叉的研究领域. 自1950年以来,已经逐步形成较完整的理论体系,算法研究也有一定的进展,应用日渐广泛. 简述了它的发展历程、主要特征、基本理论和方法,综述了国内学者近几年来在若干领域的发展状况和主要代表性成果,展望了向量优化学科未来的发展方向.     

直接转矩控制中无速度传感器技术的现状及发展

分析了无速度传感器直接转矩控制系统中各种转速估算方法,介绍了各种方法的优缺点,指出了无速度传感器控制的研究方向和发展趋势.     

超、特高压工频过电压研究综述

对超、特高压系统中工频过电压产生的原因、影响作出了说明,对超、特高压输电系统中工频过电压的研究现状进行了综述,总结了工频过电压的主要研究方法,指出了目前研究中尚未解决的一些问题。     

新型超低温探头在分析与科研中的应用

过去的几十年里,超低温探头技术是使得NMR 灵敏度得到极大提高的技术上的唯一进步. 本文详细介绍了布鲁克各种类型超低温探头的技术创新和应用实验. 布鲁克超低温探头在灵敏度上的飞跃,使得科学家可以研究以前无法研究的小量样品,样品测试的通量最高可增加16倍. 各种新型的超低温探头也将把超低温探头的应用扩展到新的领域.     

Thermal Plasma Technology: Where Do We Stand and Where Are We Going?

In this overview, an attempt is made to assess the present and future research and development in thermal plasma processing of materials restricted to (1) thermal plasma coating technologies, (2) thermal plasma synthesis of fine powders, (3) thermal plasma waste destruction, and (4) thermal plasma spheroidization and densification. Since thermal plasma processing is, in general, governed by a large number of parameters, implementation of controls becomes mandatory. The lack of sufficient controls combined with economic drawbacks in some cases has been the main obstacle for the growth of thermal plasma technology. Present R&D efforts, however, address these problems.     

北美超低渗致密油藏提高采收率技术现状

在过去的十年中，北美致密油气的开发技术日渐成熟，其中，最具代表性的技术是水力压裂和水平钻井技术的结合。然而，现有依靠天然能量的衰竭式开发只能采出超低渗储层中的少部分原油（采出程度低于10%），导致致密储层中仍存在大量剩余油。因此，非常规超低渗油藏提高采收率技术的研究日趋重要。目前，全世界90%以上的致密油产量来自美国，其开采技术在非常规致密油的开发领域具有明显优势。并且，在过去的十年间，北美的石油公司已经对针对致密低渗油藏的提高采收率（EOR）技术进行了许多现场测试。鉴于美国在非常规致密油的勘探开发中具有领先地位，重点对北美致密油资源开发中提高采收率措施的现场经验进行了总结和评价，并指出了其目前面临的主要困难和挑战。此项研究对于中国未来超低渗致密油藏提高采收率技术的发展具有指导和借鉴意义。