GTL 工艺技术评述

介绍了1990年以来GTL工艺技术开发的进展情况，其中以Sasol-SSPD和Syntruleum两种工艺最受关注，从现有数据分析。Syntruleum虽采用含氮合成气生产工艺，但并未使装置的单位投资明显改善，因此，近10年来GTL工艺技术开发虽取得了长足的进步，但其装置投资仍偏高，从而又严重影响了产品成本，按南非Sasol公司的经验。开展资源综合利用是降低液体燃料生产成本的有效途径，目前国外GTL工艺技术的开发仍很活跃，我国也已形成大量实验室成果。建议尽快组织力量完成工业性试验。     

计算机在热处理工艺编制中的应用

利用计算机强大的数据处理功能 ,对热处理工艺中的各种数据进行记录和处理 ,并制成各种图表 ,掌握其中的各种规律。使热处理工艺的编制不再是一种经验积累式的工作 ,而是依照其规律制定一次合格的规范的热处理工艺卡片 ,并为将来计算机工艺自动生成的工作打下基础     

The 2006 summary of scientific productivity of chemical engineers in Taiwan

In this report, the scientific productivity of Year 2006 of chemical engineering professionals in Taiwan was analyzed carefully with information retrieved from the database of the ISI Web of Science. The distributions of number of authors with x publication versus the number of publication x follows a general power-law trend, which coincidently comply with the Pareto distribution. The power-law indices found ranges from −1.64 to −2.22, which is consistent with values reported in the literature investigated for periods of 1907–1916 and 1969–2004.     

GaAs-GaAlAs heterostructure single-mode channel-waveguide cutoff modulator and modulator array

A GaAs single-mode channel-waveguide cutoff modulator that utilizes a GaAs-GaAlAs heterostructure and a linear array of such modulators are reported for the first time. We have measured a cutoff voltage as low as 9.0 V and an extinction ratio greater than 20 dB at an optical wavelength of 1.3 μm in a basic modulator that utilized a GaAs-Ga0.93Al0.07As heterostructure with a 0.9 μm thick GaAs epitaxial layer together with a ridge channel 2.5 mm in length and 5.0 μm in width. We have also succeeded in the realization of a high packing density (500 channels/cm) linear array of such cutoff modulators in the same GaAs substrate with equally satisfactory results. An RF bandwidth of 2.5 GHz has also been measured with the elementary modulator of such array. As in the case for LiNbO3substrates, the GaAs-based integrated optic modules that result from integration of such cutoff modulator arrays, microlens arrays, and planar acoustooptic or electrooptic Bragg diffraction grating arrays in a common substrate may be used to perform multiport switching, computing, and RF signal processing.     

水轮发电机槽楔处理的几个技术问题

水轮发电机定子槽楔处理是定子检修的关键环节,关系到定子检修质量的主要工序,在长期的、多台次的、不同机型的水轮发电机定子槽楔处理工作中,经过不断分析,对槽楔处理的技术问题进行了探讨。     

干燥器和调温调湿器的余热循环利用

阐述了大庆炼化公司腈纶厂的调温调湿器和干燥器排气的工艺流程改进。2套干燥器的流程改造稍有不同,调温调湿器2个排放总管所接管线返到各自排放的区,干燥器2个排放总管所接管线只返到1区;设备流程改造1a后,产生明显的经济效益,减少了环境污染。     

Growth temperature dependence of low-noise MESFET in molecular-beam epitaxy

The substrate growth temperature dependence of electrical properties for a low-noise MESFET fabricated on MBE-grown material has been demonstrated. The optimum noise figure and its associated gain were attributed to the higher epilayer quality and mobility at a growth temperature of 650°C between temperatures of 550°C and 700°C.     

Adherence clustering: an efficient method for mining market-basket clusters

We explore in this paper the efficient clustering of market-basket data. Different from those of the traditional data, the features of market-basket data are known to be of high dimensionality and sparsity. Without explicitly considering the presence of the taxonomy, most prior efforts on clustering market-basket data can be viewed as dealing with items in the leaf level of the taxonomy tree. Clustering transactions across different levels of the taxonomy is of great importance for marketing strategies as well as for the result representation of the clustering techniques for market-basket data. In view of the features of market-basket data, we devise in this paper a novel measurement, called the category-based adherence, and utilize this measurement to perform the clustering. With this category-based adherence measurement, we develop an efficient clustering algorithm, called algorithm k-todes, for market-basket data with the objective to minimize the category-based adherence. The distance of an item to a given cluster is defined as the number of links between this item and its nearest tode. The category-based adherence of a transaction to a cluster is then defined as the average distance of the items in this transaction to that cluster. A validation model based on information gain is also devised to assess the quality of clustering for market-basket data. As validated by both real and synthetic datasets, it is shown by our experimental results, with the taxonomy information, algorithm k-todes devised in this paper significantly outperforms the prior works in both the execution efficiency and the clustering quality as measured by information gain, indicating the usefulness of category-based adherence in market-basket data clustering.     

应用遥感图像分析九江瑞昌地区构造与金铜成矿的关系

九瑞地区是长江中下游重要的金铜成矿区,遥感图像分析认为,北东东向断裂是主要的控矿构造,与北西向断裂的交汇部位是金铜成矿的有利地段。此外,环形构造又是另外一种控矿构造,目前所发现的金铜矿床均有物化探异常显示,并形成于环形构造的边缘。