由余函数的特性函数求范德瓦耳斯气体的热力学性质

本文以范德瓦耳斯气体为例，介绍由热力学余函数的特性函数内压能来计算实际气体的热力学余函数和热力学性质．并指出这方法是一种既简便又有效的计算热力学函数的方法．     

正负温度的热力学定律

本文讨论了正负温度的热力学定律．先阐述传统的正温度热力学定律，继而阐述负温度热力学定律，形成对比和统一的鲜明印象，并把热力学三条基本定律综合为一条定律，体现了热力学定律的完整性．最后谈到１００多年来人们困惑不解的“Ｍａｘｗｅｌｌ妖”（Ｍａｘｗｅｌｌｉａｎ Ｄｅｍｏｎ ）和“热寂”（Ｈｅａｔ　Ｄｅａｔｈ）问题．     

理想气体热力学过程吸放热情况的图像判断法

如何简便地判断一个热力学过程的吸放热情况,对于了解此热力学过程是至关重要的．传统的方法是借助热力学第一定律,通过计算该热力学过程中的热学三量（功、热量和内能）来确定．文章通过分析简单热力学过程中的热容,得出：从绝热线上一点出发的微过程,过程曲线在绝热线下方,为放热过程;反之,为吸热过程．进一步,文章指出对于一些复杂的热力学过程,除使用传统的比较功大小的方法外,还可以利用热力学过程的末态相对等温线的位置而简单得出其吸放热情况。     

论Gibbs方程的热力学本性及热力学函数的物理意义

对Gibbs方程的热力学本性作了再认识,论述了热力学函数U、H、A、G的物理意义,尝试从一般的运动和势能的关系上理解热力学．     

对热力学第二定律的解析

热力学第二定律是热力学的基本定律之一，它是关于在有限空间和有限时间内，一切和热运动有关的物理、化学过程具有不可逆性的总结．同学们对热力学第二定律的理解有些困难，现从以下几个方面举例分析．     

范德瓦耳斯气体与热力学第三定律不相容

指出范德瓦耳斯气体与经典理想气体一样,也与热力学第三定律不相容．由此指明了考虑了粒子间相互作用的经典体系,仍与热力学第三定律不相容．     

非平衡定态相图新概念及其应用——激活低压金刚石气相生长热力学

在激活的低压条件下，金刚石气相稳定生长的同时石墨会被腐蚀．这是近二三十年来国际上的一个热力学难题，甚至被认为是“热力学的悖论”．用非平衡热力学耦合理论可以给予很好的解释，并推导出非平衡定态相图的全新概念．在新型相图中金刚石在低压下是稳定相，而石墨被激活成为亚稳相．理论计算与文献报道的大量实验数据定量化地相符     

毛细现象的不可逆性

根据多界面系统的热力学基本方程，给出了多界面相热力学过程的自由能判据，分析了毛细现象的不可逆性．     

关于负绝对温度的热力学概念

本文从宏观分析入手，导出温度的热力学定义，再进行微观分析，说明负绝对温度的存在，阐明其热力学特性，并对热力学中几个问题略加讨论．     

涡流管能量分离过程的热力学模型

根据工程热力学理论对涡流管工作过程进行了热力学分析,在h—s图上定性地表示出热力过程,获得了过程中相关参数的计算公式。通过对管内能量分离过程热力学分析,借助J．Mischner的热力学熵增理论,获得了涡流管内能量分离效应与冷气流率的函数关系式,建立了完整的涡流管能量分离过程的热力学模型。     

Parameter design of a liquid-filled sloshing system

<正>The nonlinear governing equations of the liquid sloshing modals in a cylindrical storage tank are established. Through analytical analysis,the analytical expressions of the solutions of this kind of system are obtained.With different parameters,the dynamical behaviors of the solutions are different from the trivial ones.To prevent system instability,two selection principles that the stiffness equations are positive-definite and the nonlinear terms of the system are not regenerative elements are given.Meanwhile,numerical simulations are also given,which confirm the analytical results.     

约束对Birkhoff系统Noether对称性和守恒量的影响

研究约束对Birkhoff系统的Noether对称性和守恒量的影响．首先，建立了Birkhoff系统的运动微分方程．其次，给出了系统Noether对称性的判据．然后，讨论了受约束作用后，Birkhoff系统的Noether对称性发生的变化，并给出了系统的Noether对称性以及守恒量保持不变的条件．最后，举例说明结果的应用． 关键词： 分析力学 Birkhoff系统 约束 Noether对称性 守恒量     

Aerial Video Trackers Review

Target tracking technology that is based on aerial videos is widely used in many fields; however, this technology has challenges, such as image jitter, target blur, high data dimensionality, and large changes in the target scale. In this paper, the research status of aerial video tracking and the characteristics, background complexity and tracking diversity of aerial video targets are summarized. Based on the findings, the key technologies that are related to tracking are elaborated according to the target type, number of targets and applicable scene system. The tracking algorithms are classified according to the type of target, and the target tracking algorithms that are based on deep learning are classified according to the network structure. Commonly used aerial photography datasets are described, and the accuracies of commonly used target tracking methods are evaluated in an aerial photography dataset, namely, UAV123, and a long-video dataset, namely, UAV20L. Potential problems are discussed, and possible future research directions and corresponding development trends in this field are analyzed and summarized.     

过渡金属原子掺杂的锯齿型磷烯纳米带的磁电子学特性

利用基于密度泛函理论的第一性原理方法,研究了掺杂铁、钴和镍原子的锯齿型磷烯纳米带(ZPNR)的磁电子学特性.研究表明,掺杂和未掺杂ZPNR的结构都是稳定的.当处于非磁态时,未掺杂和掺杂钴原子的ZPNR为半导体,而掺杂铁或者镍原子的ZPNR为金属.自旋极化计算表明,未掺杂和掺杂钴原子的ZPNR无磁性,而掺杂铁或者镍原子的ZPNR有磁性,但只能表现出铁磁性.处于铁磁态时,掺杂铁原子的ZPNR为磁性半导体,而掺杂镍原子的ZPNR为磁性半金属.掺杂铁或者镍原子的ZPNR的磁性主要由杂质原子贡献,产生磁性的原因则是在ZPNR中存在未配对电子.掺杂位置对ZPNR的磁电子学特性有一定的影响.该研究对于发展基于磷烯纳米带的纳米电子器件具有重要意义.     

亲水性材料固相萃取-紫外导数光谱法检测血中茚满二酮灯抗凝 …

本文报导了血中茚满二酮类抗凝血杀鼠剂敌鼠、氯敌鼠、杀鼠酮的亲水性材料固相萃取－紫外导数光谱检测法。血样用pＨ５缓冲液等体积稀释后加于西雷脱硅藻土柱上,柱用乙酸乙 酯洗脱,将洗脱液挥发干净,剩余物用pＨ１０缓冲液溶解,测定所得溶液的二阶导数光谱进行定性和定量分析。三种杀鼠剂以１０mg／Ｌ的量加于空白血中测得萃取率为８５％以上,血中三种杀鼠剂的检出限低于２ｍｇ／Ｌ。萃取中亲水性硅藻土可用硅胶和氧化铝代替,     

Ablation of Transparent Materials Using Excimer Lasers for Photonic Applications

For many years, the development of effective ablation or laser machining techniques for making micro-optical components has been the key factor in the birth of new photonic devices and systems. In this article, the ablation characteristics of two types of the most important transparent materials, transparent polymers and glasses, are studied. Simple shaped microcavities are first machined for studying the fundamental ablation parameters, including threshold fluence, effective absorption coefficient, and ablation rate. In studying polymer ablation, five standard grades and five proprietary polymeric compounds are selected. Ablation techniques using these transparent polymers for making arrayed ferrules and curved microlenses are presented. Applications of these ablated microstructures for optical fiber connectors, optical fiber coupling and alignment, and transparent chip encapsulants, are introduced and demonstrated with emphasis on the quality of the ablated profiles and dimensions to satisfy the required performance. In glass ablation, borosilicate glasses are considered and their associated ablation behaviors are studied. The procedures to ablate glass-based arrayed microstructures with flat and curved surfaces are described. The utilizations of these arrayed microstructures for optical waveguide, wave absorber, and beam guider, are specifically discussed. Finally, concluding remakes for future trends are presented.     

分块式变形镜的计算机模拟

本文提出了多种分块式变形镜方案,利用最佳波前匹配方法推导出了所提出的各种变形镜方案最佳参数的计算公式,并以补偿大气湍流能力的角度评价各种变形镜方案,通过计算机模拟获得了一些重要结论,为变形镜的实际制做奠定了必要的基础。     

Periodic waves in nonlinear metamaterials

Periodic waves are presented in this Letter. With symbolic computation, equations for monochromatic waves are studied, and analytic periodic waves are obtained. Factors affecting properties of periodic waves are analyzed. Nonlinear metamaterials, with the continuous distribution of the dielectric permittivity obtained, are different from the ones with the discrete distribution.     

On the fractal characterization of Paretian Poisson processes

Paretian Poisson processes are Poisson processes which are defined on the positive half-line, have maximal points, and are quantified by power-law intensities. Paretian Poisson processes are elemental in statistical physics, and are the bedrock of a host of power-law statistics ranging from Pareto’s law to anomalous diffusion. In this paper we establish evenness-based fractal characterizations of Paretian Poisson processes. Considering an array of socioeconomic evenness-based measures of statistical heterogeneity, we show that: amongst the realm of Poisson processes which are defined on the positive half-line, and have maximal points, Paretian Poisson processes are the unique class of ‘fractal processes’ exhibiting scale-invariance. The results established in this paper are diametric to previous results asserting that the scale-invariance of Poisson processes–with respect to physical randomness-based measures of statistical heterogeneity–is characterized by exponential Poissonian intensities.