首秦1号高炉降低燃料比和提高喷煤比的工业实践

首秦1号高炉的技术装备、工艺水平、自动控制和环保节能等方面的新技术都达到了较高水平。高炉达到设计指标后,在原燃料质量不断提高的同时,采用技术创新与技术进步,解决了高炉单系统流程给生产带来的新问题,使得新技术、新装备能力达到较高水平,生产综合指标不断提高。实现燃料比低于492 kg/t,煤比高于180kg/t,在国内同类高炉中位于领先的水平。     

丰满大坝历年灌浆情况综述

丰满大坝运行之初渗漏严重,测到的最大渗漏量达16380L/min,为了防渗堵漏和降低坝体扬压力,对大坝进行了近60年的多次灌浆处理,本文综述了历次灌浆情况。     

基于烧结基础特性的新评价方法指导烧结配矿

 对国外10种常见的铁矿粉进行了研究,着重测试其烧结基础特性。考虑到以往烧结基础特性的评价指标忽视过程信息,使用模拟烧结过程中的单个因素指标对烧结基础特性指标进行定量描述的特点, 采用了一种全新的评价指标,该指标包含了烧结的过程信息,因此能较全面地对毅星粉的烧结基础特性进行评价。根据新方法对不同配矿方案的烧结杯试验结果进行预测,烧结杯试验结果证明了该预测的有效性,试验结果认为,巴卡粉与毅星粉在小比例配比条件下可进行互替。     

Inkjet printing of multi-walled carbon nanotube/polymer composite thin film for interconnection

In this paper, multi-walled carbon nanotube (MWCNT) ink was selectively patterned by inkjet printing on substrates to form conductive traces and electrodes for interconnection application. MWCNT was firstly functionalized using concentrated acid and dispersed in deionized water to form a colloidal solution. Various concentrations of MWCNT were formulated to test the stability of the solution. The printability of the MWCNT ink was examined against printing temperature, ink concentration and ink droplet pitch. Rheological properties of the ink were determined by rheometer and sessile drop method. The electrical conductivity of the MWCNT pattern was measured against multiple printing of MWCNT on the same pattern (up to 10 layers). While single layer printing pattern exhibited highest resistance, the CNT entangled together and formed a random network with more printed layers has higher conductivity. The electrical properties of the printed film was compared to a composite ink of CNT and conducting polymer (CNT ink was mixed with conductive polymer solution, Poly(3,4-ethylenedioxythiophene)-Poly(styrenesulfonate) (PEDOT:PSS)). Scanning electron microscopy (SEM) was used to observe the surface structure and atomic force microscopy (AFM) was used to study the morphology of the printed film under different conditions.     

COREX炉内块煤裂化成焦的热态强度

通过对COREX所用2种块煤在不同条件下所成半焦的显微结构、热态强度进行观察,分析了影响块煤成焦质量的内在因素。比较2种块煤所成半焦的组成结构及性能差异后,发现兴隆庄煤成焦结构要优于大同煤,但兴隆庄原煤组织反应性较高,故在前期其煤成焦强度低于大同煤,直至成焦结构较多时,才高于大同煤。通过对COREX风口焦及实验室自制半焦的微观形貌和性能进行对比,确定了风口焦的来源,风口前兴隆庄煤形成焦炭的表面呈现出较浅的孔洞,其热态强度明显高于大同煤形成的焦炭。     

高炉大型化后对焦炭性质及在炉内劣化的思考

 焦炭作为高炉炼铁的主要燃料,对高炉的顺行和高效冶炼发挥着极其重要的作用,随着高炉大型化和智能化的发展,对焦炭质量及对其的评价、预测和控制的要求亦越来越高。针对高炉内不同部位焦炭的劣化经历、劣化后焦炭的高温反应特性及焦炭组织结构的变化进行了分析。依据国内一些特大型高炉的生产实践,提出了在达到高水平高炉操作指标时不同容积高炉焦炭高温反应特性所需的指标,并对适合评价高炉大型化焦炭劣化后质量的标准做了探讨。     

靶电流对TiAIN/TiN复合膜组织及硬度的影响

采用多弧离子镀技术在 40Cr 基体上制备 TiAlN/TiN 复合膜层,通过金相显微镜、扫描电镜和显微硬度仪研究靶电流对膜层表面形貌、沉积率及硬度的影响.结果表明:靶材电流对膜层组织和硬度有显著影响,电流越高膜层表面越不平整,显微硬度随靶材电流的升高先上升后降低.靶电流越高,膜层中 Ti、Al 原子的含量就越高.     

Stream Cube: An Architecture for Multi-Dimensional Analysis of Data Streams

Real-time surveillance systems, telecommunication systems, and other dynamic environments often generate tremendous (potentially infinite) volume of stream data: the volume is too huge to be scanned multiple times. Much of such data resides at rather low level of abstraction, whereas most analysts are interested in relatively high-level dynamic changes (such as trends and outliers). To discover such high-level characteristics, one may need to perform on-line multi-level, multi-dimensional analytical processing of stream data. In this paper, we propose an architecture, called stream_cube, to facilitate on-line, multi-dimensional, multi-level analysis of stream data. For fast online multi-dimensional analysis of stream data, three important techniques are proposed for efficient and effective computation of stream cubes. First, a tilted time frame model is proposed as a multi-resolution model to register time-related data: the more recent data are registered at finer resolution, whereas the more distant data are registered at coarser resolution. This design reduces the overall storage of time-related data and adapts nicely to the data analysis tasks commonly encountered in practice. Second, instead of materializing cuboids at all levels, we propose to maintain a small number of critical layers. Flexible analysis can be efficiently performed based on the concept of observation layer and minimal interesting layer. Third, an efficient stream data cubing algorithm is developed which computes only the layers (cuboids) along a popular path and leaves the other cuboids for query-driven, on-line computation. Based on this design methodology, stream data cube can be constructed and maintained incrementally with a reasonable amount of memory, computation cost, and query response time. This is verified by our substantial performance study. Recommended by: Ahmed Elmagarmid     

Helmet use and motorcycle fatalities in Taiwan

Motorcycle deaths accounted for more than half of total traffic fatalities in Taiwan in 2002. This study uses the police-reported crash data from Taiwan between 1999 and 2001 to estimate the effectiveness of helmets, simultaneously taking into account of sample selection bias. Sample selection arises because helmet usage will affect the probability of death or injury, which in turn influences whether a crash is included in the data. The results show that sample selection does not seriously bias the estimate of helmet effectiveness and helmets reduce the probability of death in a crash by 40%, which is higher than what was previously found. Without helmets, the number of motorcyclists killed in 2001 would have jumped by 51%. The estimated proportion of helmeted motorcyclists has increased from 71 to 78% between 1999 and 2001, suggesting that helmet use is rising after the implementation of mandatory helmet law in 1997. Also, helmets significantly reduce the likelihood of head and neck injuries in a crash by 53%, and lead to a 71% reduction in the probability of death caused by head and neck injuries.