高炉冷却壁失效原因研究

本文针对安钢高炉冷却壁破损的形式、原因进行研究分析,探讨了冷却壁的结构、材质、加工与安装工艺对其寿命的影响。介绍了安钢高炉炉役后期冷却壁的维护生产实践。     

Belgian Experiences in the Ozonization of Water

After reviewing the uses of ozone in the preparation of drinking water, high purity water for Pharmaceuticals industries, and swimming pools throughout Belgium, a discussion of technological developments made at the Tailfer plant (serving Brussels) concerning the uses of ozone is presented. These subjects include analytical and monitoring techniques developed for ozone, procedures for ozone contacting employed at this plant, treatment of ozone contactor off–gases, and the use of oxygen–enriched process gas to produce supplemental amounts of ozone required periodically. Capital and operating cost data are presented.     

Web-based Assessment and Test Analyses (WATA) system: development and evaluation

This study introduces the development of a Web‐based assessment system, the Web‐based Assessment and Test Analyses (WATA) system, and examines its impacts on teacher education. The WATA system is a follow‐on system, which applies the Triple‐A Model (assembling, administering, and appraising). Its functions include (1) an engine for teachers to administer and manage testing, (2) an engine for students to apply tests, and (3) an engine for generating test results and analyses for teachers. Two studies were undertaken to assess the usefulness and potential benefits of the WATA system for teacher education. In the first study, 47 in‐service teachers were asked to assess the functions of the WATA system. The results indicated that they were satisfied with the Triple‐A Model of the WATA system. In the second study, 30 pre‐service teachers were required to use the WATA system during the teacher‐training program. After 4 months of experience in using the WATA system, the pre‐service teachers' perspectives of assessment have been changed significantly. The findings of these two studies might provide some guidance to help those who are interested in the development of Web‐based assessment and intend to infuse information technology into teacher education.     

聚丙烯酰胺浓度测量方法综述

本文综述了１１类测量ＨＰＡＭ浓度的方法，讨论了每一种方法的原理、特点、干扰因素和应用范围。     

螺旋榨油机榨排的设计计算

设计计算榨排时如何选择材料、类型和结构作了简要述叙，对榨排的受力进行了分析，同时对不同榨排进行了强度计算和校核。     

Using a modified CINDER90 routine in MCNPX 2.6.0 for the prediction of helium production in minor actinide targets

Fast reactors containing heterogeneous minor actinide (MA) target rods are now being modeled. When studying transmutation in these rods, helium production from α-decay must be considered since it is produced in substantial quantities. This research utilized an innovative method to calculate gas production by modifying the CINDER90 depletion code used by MCNPX 2.6.0 to include helium production from α-decay. The modified CINDER90 code was verified using the ORIGEN-ARP module of SCALE6. It was tested using the Sodium-Cooled Heterogeneous Innovative Burner Reactor model created at the University of South Carolina. It is recommended that the modified version of the cinder.dat file be distributed in subsequent MCNPX 2.6.0 releases for use in fast reactor calculations using heterogeneous MA target rods since it includes helium production otherwise not available from the current version.     

Carotenoid composition of the fruits of Capsicum annuum Cv. Bovet 4 during ripening

 The changes in the carotenoid pigments of the Capsicum annuum cv. Bovet 4 during ripening have been investigated quantitatively by means of an HPLC technique. In the chromatograms, 56 peaks were detected and 34 carotenoids were identified. In the ripe fruits, capsanthin, capsorubin, zeaxanthin, cucurbitaxanthin A, and β-carotene were found to be the main carotenoids, the remainder being capsanthin 5,6-epoxide, capsanthin 3,6-epoxide, karpoxanthin, cucurbitaxanthin B, violaxanthin, cycloviolaxanthin, antheraxanthin, capsanthone, nigroxanthin, β-cryptoxanthin and several cis isomers and furanoid oxides. Received: 16 April 1997     

复合土钉墙现场测试及数值模拟分析研究

整理分析了济南西部新城某地下车库基坑的复合土钉墙支护结构现场监测数据,采用有限元软件ABAQUS建立基坑支护结构单元三维模型,模拟了其开挖支护施工过程,动态分析基坑边坡坡顶地表水平位移、沉降变化规律,并与现场监测值进行对比,分析了微型桩与止水帷幕对复合土钉墙的影响。表明由土钉、止水帷幕、微型桩、预应力锚杆与土体相互作用的有限元力学模型能较好模拟复合土钉墙支护施工过程,结果可供同类复合土钉墙设计施工提供参考。     

Analysis and monitoring of chloramphenicol residues in food of animal origin in Slovenia from 1991 to 2000

To prevent the illegal use of chloramphenicol (CAP), regulatory control of its residues in food of animal origin is essential. In Slovenia, the monitoring of CAP residues for statutory purpose started in 1991. The results of a 10-year period are presented. CAP residues were determined by capillary gas chromatography (GC) with electron capture detection (ECD) using meta-CAP as an internal standard (ISTD). Before chromatographic determination, analytes were derivatized by silylation. Overall, CAP recovery, adjusted for ISTD, was for bovine muscle tissue and raw cow's milk (in the region of 2-10 μg kg^-1) 89 and 102%, respectively, and for whole eggs, 87% (in the region of 1-10 μg kg^-1). The use of meta-CAP improved significantly the precision of the method. The detection limit for CAP was 1 μg kg^-1, which was sufficiently sensitive for routine use. A total of 1308 random samples of Slovenian origin were analysed from 1991 to 2000, covering all parts of the country. CAP was found only in one milk sample in 1997 at a concentration of 4.6 μg kg^-1.     

An electrical circuit analogy model for analyses and optimizations of the Stirling-type pulse tube cryocooler

The existing electrical circuit analogy (ECA) models are mainly used to optimize the inertance tube and to analyze the crude phase of the dynamic pressure and the volume flow rate. The specific analyses and optimizations of other components or the whole Stirling-type pulse tube cryocooler (SPTC) with the ECA model have not been carried out. In this paper, a new ECA model including the main components of the SPTC such as regenerator, pulse tube, phase shifter and reservoir has been developed. To improve the practicability of the ECA model, based on the basic governing equations, calculation expressions of the above components are worked out, and their equivalent analogical electrical elements are defined according to the analogy theory. Through the developed ECA model, the specific pressure and volume flow rate at any position can be acquired. Further optimizations on the SPTC based on the ECA model show that, with the same pressure and PV power at the warm end of the regenerator, there exists an optimal phase angle between the pressure and the volume flow rate for the SPTC to achieve the highest gross cooling capacity. In addition, with the same ratio of the pressure to the volume flow rate and the same phase angle between them at the warm end of the regenerator, when the regenerator ineffectiveness loss is neglected, the SPTC efficiency keeps constant with variations of the PV power, however, the efficiency will increase with the increase of the PV power if the loss is considered.