多孔聚合物微球成孔技术的最新研究进展

综述了多孔聚合物微球的制备方法及成孔机理。种子溶胀法和微膜乳化法用于制备具有微孔、中孔结构的单分散聚合物微球;而大孔聚合物微球的制备通常采用传统的悬浮聚合,并通过后交联法改善其孔性能,提高其比表面积。     

基于图型矢量距离的多点地质统计相建模算法

多点地质统计建模算法已由基于概率模拟发展到基于相似度模拟的新阶段,基于相似度模拟的算法的关键是从训练图像中选取与数据事件最为相似的训练图型。以Simpat算法为基础发展起来的最具代表性的Filtersim和DisPat算法,采取先聚类、再匹配的建模策略,在训练图型选取的计算效率上较Simpat算法具有明显改进,但其匹配数据事件与训练图型仍采用标量距离度量二者相似度的方法。标量距离度量相似度的方法虽然具有较好的图形识别功能,但对于具有地质意义的训练图型（而非单纯的几何图形）,该方法的相似度判断往往难以获取在地质含义上与数据事件最佳匹配的训练图型。考虑图型选取过程中的地质含义,兼顾实际储层的非平稳性,提出了基于图型矢量距离的多点地质统计相建模算法。新算法在训练图型和数据事件矢量距离计算的基础上,采用二次匹配方式通过矢量距离对数据事件与训练图型的相似度进行度量,最终确定与数据事件相似度最大的训练图型。以文献算例定性和定量对比了新算法和Snesim、Filtersim、DisPat算法的建模效果,并以实际油藏为例,对比了新算法与传统两点建模方法、Snesim和DisPat算法的建模效果。结果表明,新算法显著降低了训练图型选取的不确定性,所建模型更符合地质认识,从而为复杂油气藏相建模提供了一种新的方法。     

Lab-on-a-chip: a component view

Miniaturization is being increasingly applied to biological and chemical analysis processes. Lab-on-a-chip systems are direct creation of the advancement in the miniaturization of these processes. They offer a host of exciting applications in several areas including clinical diagnostics, food and environmental analysis, and drug discovery and delivery studies. This paper reviews lab-on-a-chip systems from their components perspective. It provides a categorization of the standard functional components found in lab-on-a-chip devices together with an overview of the latest trends and developments related to lab-on-a-chip technologies and their application in nanobiotechnology. The functional components include: injector, transporter, preparator, mixer, reactor, separator, detector, controller, and power supply. The components are represented by appropriate symbols allowing designers to present their lab-on-a-chip products in a standard manner. Definition and role of each functional component are included and complemented with examples of existing work. Through the approach presented in this paper, it is hoped that modularity and technology transfer in lab-on-a-chip systems can be further facilitated and their application in nanobiotechnology be expanded     

浅谈当代教育的基本特点

教育是培养人、造就人的一种社会活动,它既要体现社会的要求,反映人的身心发展的规律,又要富于创造精神.通过教育活动的实施,受教育者不仅要掌握人类在过去的实践中所获得的理论知识、实际技能以及形成一般社会所要求的思想品德,而且要形成开拓、创新、不囿于成见的个性心理和内在品质,这也是教育的终极目的和最高境界.     

Hybrid integration of VCSEL's to CMOS integrated circuits

Three hybrid integration techniques for bonding vertical-cavity surface-emitting lasers (VCSELs) to CMOS integrated circuit chips have been developed and compared in order to determine the optimum method of fabricating VCSEL based smart pixels for optical interconnects and free-space optical processing. Each of the three bonding techniques used different ways of attaching the VCSEL to the integrated circuit and making electrical contacts to the n- and p-mirrors. All three techniques remove the substrate from the VCSEL wafer leaving an array of individual VCSELs bonded to individual pixels. The 4×4 and/or 8×8 arrays of bonded VCSELs produced electrical and optical characteristics typical of unbonded VCSELs. Threshold voltages down to 1.5 V and dynamic resistance as low as 30 Ω were measured, indicating good electrical contact was obtained. Optical power as high as ~10 mW for a VCSEL with a 20-μm aperture and 0.7 mW with a 6-μm aperture were observed. The VCSELs were operated at 200 Mb/s (our equipment limit) with the rise and fall times of the optical output <1 nS     

Spectroscopic and thermal behavior of ZnHg(SCN)4

The synthesis and purification of zinc mercury thiocyanate, ZnHg(SCN)₄ (ZMTC), are described. The identity of the synthesized compound was characterized by elemental analysis, X-ray powder diffraction, infrared, Raman, and UV/Vis/NIR transmission spectra. The thermal stability and thermal decomposition of ZMTC crystal were investigated by means of thermogravimetric analysis (TGA) and differential scanning calorimetry (DSC) measurements. The intermediates and final products of the thermal decomposition were identified by X-ray powder diffraction (XRPD).     

Phase correlation between longitudinal modes in semiconductor self-pulsating DBR lasers

Phase correlation leading to self-pulsation (SP) in semiconductor distributed Bragg reflector (DBR) lasers is investigated experimentally and theoretically. Under proper biasing conditions, the laser oscillates with three main modes and we observe that each two-modes beating provides SP with identical spectral linewidth. Under the same operating conditions, the measured spectral linewidths of the beating modes are much larger than the linewidth of the self-pulsating signal. These results demonstrate the natural occurrence of passive mode-locking (PML) and phase correlation in semiconductor DBR lasers. A model based on multimode coupled-wave rate equations, including four-wave mixing (FWM), is developed to describe PML and SP in the gain region of the laser cavity. This model demonstrates that the existence of phase correlation between longitudinal modes is due to FWM.     

DCS系统在工业锅炉过程控制中的应用

论述了DCS系统及工业锅炉过程控制的特点，以及DCS系统在工业锅炉过程控制中的应用。     

不同激发剂对烧煤矸石活化的研究

单独用Ca（OH）2对烧煤矸石进行激发，所得材料的各个龄期的强度均很低。向该体系中引入一定比例的盐类（CaCl2、Na2SO4、NaCO3），在一定程度上提高了材料的早期和后期抗压强度。其中引入CaCl2的效果最好。对几种体系的水化产物进行XRD分析可知，3种盐类对基准体系的激发能力为CaCl2〉Na2SO4〉Na2CO3。基准体系（烧煤矸石＋氢氧化钙）＋CaCl2体系水化28d的红外光谱图中由于Si-O-Si非对称伸缩振动引起的吸收峰移向了更低的波数。表示有较多的Si被Al所取代，体系的水化产物聚合度高一些。