激光重熔氧化锆陶瓷涂层的相变过程

钛合金表面等离子喷涂氧化锆涂层激光重熔后,得到重熔区、过渡区和热影响区。本文采用SEM、TEM和X射线衍射对激光重熔前后各区的相变过程进行了研究。结果表明喷涂涂层激光重熔后,重熔区C-ZrO_2失稳得到T-ZrO_2,但无大量的M-ZrO_2出现过渡区由熔池底部的α-Ti和其前沿的粒状ZrO_2组成。粒状组织内由T-ZrO_2、M-ZrO_2和C-ZrO_2三相组成。     

激光斑纹反差测量乳状液颗粒大小

直接由光强分布导出散斑平均反差与乳状液颗粒大小的关系;报道了首次用激光斑纹反差测量乳状液颗粒大小的结果。     

线电流摇摆场中电子的自发辐射与受激辐射的关系

根据经典辐射理论计算出了电子在线电流摇摆扬中运动产生的自发辐射强度分布;利用单粒子方法推导出了自发辐射与受激辐射的关系．结果表明：线电流摇摆场中自发辐射与受激辐射的关系与普通摆动器自由电子激光中的Ｍａｄｅｙ定理有非常相似的形式,但第二部分相差一个因子．     

照排技术处理与编校质量

本文主要从照排技术角度,指出了软件版本及照排技术处理对文稿编排质量的影响,同时对这些问题提出一些解决方法。     

Assessment of the state of conservation of stone artworks after laser cleaning: comparison with conventional cleaning results on a two-decade follow up

The utilization of laser light to produce fine and selective cleaning of superficial deposits and encrustation from stones was originally proposed more than 20 years ago by John Asmus who performed pioneering trials of laser cleaning on stone façades in Venice, Cremona and Padua. The opportunity to collect stone samples from these sites allowed us to carry out an original study aimed at evaluating the conservation state of stone surfaces cleaned 10–20 years ago by means of three different techniques: Nd:YAG laser radiation, micron sandblasting and chemical pads. Samples of various stone types, as Istria limestone, Botticino limestone and Nanto sandstone were collected and examined by means of optical and SEM microscopy, FT/IR, and EDAX analyses. The results provided preliminary indications that the state of conservation of stone surfaces previously subjected to laser cleaning is generally better in comparison with those which concurrently underwent mechanical and chemical cleaning.     

A novel method for fabricating polydimethylsiloxane microfluidic chip master molds

We proposed a novel method of fabricating polydimethylsiloxane （PDMS） microfluidic chip polymer master molds in this paper. The method mainly includes two steps. First, a stainless steel slice was laser etched to form a metal model. Then, the organic solution of poly（methyl methacrylate） （PMMA） was casted onto the metal model to fabricate the PMMA master which subsequently would be used to fabricate PDMS chips. We systematically researched different laser parameters influencing the surface status of microchannels and obtained optimized etching parameters. We investigated and optimized the organic solution composition of PMMA while casting chip masters, and developed a method to form fine polymer masters using two different viscosity solutions to cast the model in turn, and studied the repeatable replication. Then, we investigated physical performance of this chip and evaluated the practicability by analyzing Rhodamine B. Compared with present methods, the proposed method does not need photolithography on photoresistant and chemical etching. The entire fabricating progress is simple, fast, low-cost and can be controlled easily. Only several minutes are required to make a metal model, 3 hours for a PMMA master, and one day for PDMS chips.     

关联维数在半导体激光器混沌同步中的特性

基于闭环混沌同步通信系统,分析了激光器混沌同步的质量同关联维数的关系。数值模拟结果表明,在适当偏置电流取值下,可以从两激光混沌系统中奇异吸引子的关联维数上看出混沌同步的好坏。由此说明,关联维数可以作为表征半导体激光器混沌同步好坏的依据。     

标准圆柱直齿轮齿面激光硬化入射角的计算

文章提出了标准圆柱直齿轮在齿面激光硬化时一系列入射角的计算方法。通过18个不同齿数直齿轮的入射角计算实例进行研究分析,得出一些有意义的结论,并对激光硬化齿面工艺方案进行了实用性的探讨。     

应用于中高速SAR ADC的低功耗少开关开关方法

提出一种应用于中高速逐次逼近型模数转换器（successive approximation register analog-to-digital converter,SAR ADC）的低功耗开关方法,该开关方法不需要额外的基准产生电路,并且需要的开关数量最少。使用重置序列（0 1…1）而不是（1 1…1）可以使得第2个位转换周期消耗的开关能量为0。为了进一步降低功耗,参考电容C使用C/2（两个C串联）并联来实现,这样所需要的C的数量又减少了将近一半,开关功耗又减少了一半。在同样的开关数量下,提出的开关方法消耗开关能量和需要的电容面积最小     

诺贝尔奖级科技突破是怎样取得的?——田中耕一发明软激光解吸电离法案例研究

考察了日本岛津制作所20世纪80年代启动激光解吸电离飞行时间质谱仪研究项目的背景,探讨了田中耕一这位2002年诺贝尔化学奖获得者从事生物大分子软激光解吸电离法开发的过程,并对这位无研究生学历、无海外留学经历、无高级职称、无行政管理职务、无SC I论文的年轻工程师取得诺贝尔奖级科技突破的主要原因进行了分析和总结。