利用高氮化能力的熔剂精炼钢除氮

利用试验技术通过调整和精确控制１８７３Ｋ时的氧分压Ｐｏ２测定了Ａｌ２Ｏ３－ＣａＯ－ＴｉＯ２和ＣａＦ２－ＴｉＯ２熔剂中氮的溶解度和氮化能力。据试验发现，熔渣和铁水之间的氮分配比以及金属的脱氮度是Ｐｏ２的函数。文章研究了采用含ＴｉＯ２的熔剂从纯铁和铬合金钢中的除氮工艺，即首先把炉渣与金属粉末混合，然后在１８７３Ｋ坩埚中加热熔化，并将熔融金属从１０ｋｇ感应炉出钢至包中。系统中的氧分压可通过精炼剂中铝或钛含量进行调整。试验结果表明Ａｌ２Ｏ３－ＣａＯ－ＴｉＯ２渣可除去低合金钢中氮，脱氮度可超过６０％。文章讨论了生产过程中采用含ＣａＦ２－ＴｉＯ２熔剂的炉渣进行钢包处理有效去除高合金钢中氮的技术参数。     

GH136合金电渣重熔渣系统的研究

本文论述了ＧＨ１３６合金电渣重熔过程，通过采取适当的渣制度，以获得良好的钢锭表面质量及较为稳定的轴向化学成分，并探讨其机理，试验表明，采用试验用渣比以前沿用的二元渣系（ＣａＦ２：Ａｌ２Ｏ３＝７０：３０），显著提高钢锭的表面质量及轴向化学成分的稳定性，初步认为，试验用渣提高渣－金界面张力；渣中ＭｇＯ控制在５～１０％，能显著地低渣系熔点，ＭｇＯ还能降低渣中ＴｉＯ２活度系数，同时提高Ａｌ２Ｏ３Ｔｉ３Ｏ５     

索拉克·敦刻尔克RH－OB装置上两个辅助风口的使用

采用ＮＳＣ氧枪去除ＲＨ－ＯＢ真空室的结瘤。为了在生产低碳钢时实现部分自动清扫，在中间环进行吹氧，这种方法能提高两个真空室的运行率。     

GH136合金电渣重熔渣系的研究

本文论述了ＧＨ１３６合金电渣重熔过程，通过采取适当的渣制度，以获得良好的钢锭表面质量及较为稳定的轴向化学成分，并探讨其机理，试验表明：采用试验用渣比以前沿用的二元渣系（ＣａＦ２：Ａｌ２Ｏ３＝７０：３０）显著提高钢锭的表面质量及轴向化学成分的稳定性。初步认为，试验用渣提高渣－金界面张力：渣中ＭｇＯ控制在５～１０％，能显著降低渣系熔点，ＭｇＯ还能降低渣中ＴｉＯ２活度系数，同时提高Ａｌ２Ｏ３，Ｔｉ３Ｏ５     

钨在碱性溶液中的阳极行为

本文研究了钨在ＮａＯＨ－ＫＣｌＯ３－Ｋ２ＣＯ３系电解液中阳极活化－钝化的转变，增加ＮａＯＨ浓度能促使钨的活化溶解，在活化区锡以＋６价进入溶液，在钝化时生成ＷＯ２钝化膜，试验测定了钨的表面活化能。     

GH136合金电渣重熔渣系的研究

本文论述了ＧＨ１３６合金电渣重熔过程，通过采取适当的渣制度以获得良好的钢锭表面质量及较为稳定的轴向化学成份，并探讨其机理。试验表明，采用试验用渣比以前沿用的二元渣系，显著提高钢锭的表面质量及轴向化学成份的稳定性。初步认为，试验用渣提高渣－金界面张力，渣中ＭｇＯ控制在５－１０％，能显著降低渣系熔点，ＭｇＯ还能降低渣中ＴｉＯ２活度系同时提高Ａｌ２Ｏ３，ｔＩ３ｏ５活度系数，起到间接保Ｔｉ的任用１。     

高纯铌的制备

详细讨论了各种杂质在铌提纯过程的行为，指出萃取，电解精炼能有效地除高熔点Ｔａ，Ｗ杂质；电子束精炼是去除一般金属杂质及低熔点杂质的常用手段；而超高真空退火则能使间隙固溶杂质的含量降低到很低的极限。并推荐了一种高纯铌制备了工艺：Ｎｂ２Ｏ３萃取→Ｎｂ２Ｏ５还原→电解精炼→电子束精炼→电子束悬浮区域熔炼→超高真空退火→高纯铌。最后还介绍了三种新型精炼方法。     

铝熔体与SiO2颗粒反应现象分析

本文分析了向纯铝液中添加ＳｉＯ_２颗粒产生的现象。试验结果表明，铝熔体与ＳｉＯ_２颗粒能发生放热反应，从而制备出Ａｌ／Ａｌ２Ｏ３颗粒原位复合材料。     

冷固结含碳球团用于COREX的可行性研究

通过对采用不同粘结剂的３组冷固结含球团的物化性能，冶金性能的试验检测，以及固定床、移动床竖炉模拟ＣＯＲＥＸ预还原的试验研究，探讨冷固启才用于ＣＯＲＥＸ工艺的可行性。试验结果表明，冷固结含碳球团的化学成分和高温冶金性能均能满足ＣＯＲＥＸ预还原的要求，并可以提高整个ＣＯＲＥＸ工艺的生产率，但其机械强度有待进一步提高。     

酸浸闪锌矿过氧化氢除铁方法研究

试验了用控制添加过氧化氢的方法从含硫酸锌和硫酸铁的硫化锌矿酸浸液中分批沉淀针铁矿，发现在ｐＨ＝３．０～４．０，温度为８０℃±，反应Ｆｅ３＋＋３ＯＨ－→ＦｅＯ（ＯＨ）＋Ｈ２Ｏ能较完全地进行，溶液中Ｆｅ离子最终浓度低于５０ｐｐｍ。     

The use of whole blood absorbed on filter paper to detect Wuchereria bancrofti circulating antigen

The Og4C3 enzyme-linked immunosorbent assay (ELISA) to detect circulating Wuchereria bancrofti antigen uses 50 microL of serum. In this study, a whole blood sample absorbed on filter paper was tested as a substitute for serum. Serum samples were obtained from 60 Sri Lankan subjects by venepuncture and finger-prick blood samples from the same individuals were directly absorbed on filter paper. Og4C3 ELISAs using serum and filter paper blood were compared. Despite the fact that the estimated amount of serum available for the ELISA with filter paper blood was only one-fifth of that available when serum was used, the 2 ELISAs gave almost identical results. Of the 39 positive serum samples, 38 were detected using filter paper blood. Employing the ELISA using filter paper blood, 619 people in Matara, Sri Lanka, were examined for antigenaemia. The positivity rate was 22.5%, 3.1 times higher than the rate of microfilaraemia detected by examination of 60 microL blood films.     

Thermal Ice Growth: Real-Time Estimation

The quasi-steady thermal ice growth model was recast in state-space form and used with the Kalman filter to estimate ice thickness and to recursively estimate the model parameters for thermal ice growth. This approach was appropriate at locations where measurements of the ice thickness were made during the study. The model was applied to two widely separated sites from which ice thickness measurements were available for a number of winters: Post Pond, N.H., and Snowshoe Lake, Alaska. The parameters required by the Kalman filter were estimated through numerical experiments and were consistent between both locations. The Kalman filter was able to produce better results, as measured by a least-squares criterion, than a model using parameter values that had been determined using all data at each location.     

Improved Estimation of ADCP Apparent Bed-Load Velocity Using a Real-Time Kalman Filter

An estimate of apparent bed-load velocity (v) can be derived from the difference between differential global positioning system (DGPSs) and acoustic Doppler current profiler (ADCP) bottom track (BT) measurements when BT is biased by a moving bottom. A Kalman filter has been developed to integrate GPS and bottom track data to improve estimation of boat velocity during ADCP measurements under moving bed conditions (Rennie and Rainville, 2008, J. Hydraulic Eng., in review). The boat velocity estimated using the Kalman filter is superior to boat velocity from raw GPS data. In this paper we assess the improvement in estimation of v using the Kalman filter as opposed to raw GPS data. Specifically, a synthetic moving bed bias was generated for 22 repeat transects of the Gatineau River, Quebec. The synthetic moving bed bias had mean, variance, and distribution across the section as typically observed during bed-load transport conditions, and had the advantage that it was known explicitly. The errors in estimated apparent bed-load velocity derived using either raw DGPS data or the Kalman filter boat velocity were compared. It was found that the improved boat velocity from the Kalman filter yielded significantly (α = 0.05) better estimates of v, (e.g., 61% reduction in error when the Kalman filter boat velocity was used instead of wide area augmentation system GGA), because boat velocity errors were reduced. Tests with real moving bed data confirmed the Kalman filter was able to significantly reduce errors in bed load calculated with stand alone GPS.     

Cyclins: relevance of subcellular localization in cell cycle control

OBJECTIVE: To develop a filter utilizing mathematical theory to extract the skeletal patterns of trabecular bone. METHODS: Studies of morphology in the extraction of patterns of calcification in mammograms provided the theoretical framework. Using these studies as a basis, a morphological filter was applied to extract skeletal patterns from digital images of trabecular bone. Sequential images (subset) were combined in a structured fashion to create an aggregate (sumset) which compared with the original images, skeleton and line skeleton images. RESULTS: Binary images of the skeletal patterns in continuous, round and mesh-like forms were obtained from the original images by processing with the skeleton operation using a disc-shaped single structuring element. The line skeleton operation using line structuring elements with constant directions allowed the extraction of linear and discontinuous patterns. Both the skeleton and line skeleton operations extracted binary subset images which depicted skeletal patterns correlating with the operation sequence. CONCLUSIONS: Modification of the morphological filter enhanced the extraction of skeletal characteristics of trabecular bone. A morphological filter may be a useful adjunct in computer-aided structural analysis of bone.     

Comparison of the Ability of Three Coagulants to Enhance Filter Performance

In the operation of porous media filtration systems, poor initial performance is often observed, in which particle removal is less than desired. Alum (Al2(SO4)3?14H2O), ferric chloride (FeCl3), and polyaluminum chloride (PACl), are often used in drinking-water treatment to modify the surface properties of the particles being filtered and enhance their removal by filters; however, modification of the filter medium is not a common practice. In this research, these three coagulants were used to artificially modify a sand medium in situ by adding metal hydroxide precipitates onto the top of the filter before challenging the filter with an otherwise untreated kaolin suspension. After modification of the filter medium, high particle-removal efficiencies were achieved using a short (7.5?cm) sand column with ? 1??mm diameter sand. The best observed particle removal (96%) using alum and PACl occurred at the surface loading of 550?mmol of Al/m2. The filter performance deteriorated at higher surface loadings. Fractional colloid removal increased with increased ferric chloride surface loading over the entire range of dosages tested (up to 97.5% at 2,200?mmol Fe/m2). The experimental results suggest that pretreatment of filter media by application of Fe or Al hydroxides can eliminate the initial poor performance.     

中间包通道式过滤器对硅钢W470中夹杂物的影响

利用小样电解+ ASPEX扫描电镜等夹杂物检测方法,研究了使用中间包通道式过滤器前后的冲击区和浇注区的钢液以及铸坯中非金属夹杂物类型和尺寸的变化规律.结果 表明,使用过滤器后,浸入式水口基本未堵塞;过滤器对夹杂物尺寸大于30 μm以上的夹杂物颗粒有良好的去除效果;从夹杂物总数来看,冲击区＞铸坯＞浇注区,这是因为浇注区钢...     

Quantification of the effects of respiration and parallax on inferior vena caval filter position

PURPOSE: The change in inferior vena caval (IVC) filter position at follow-up relative to the filter position at implantation has been used as a criterion for evaluation and comparison of these devices. Perceived changes in filter position may be due to respiratory movement and/or changes in parallax between the initial and follow-up imaging studies. In this study the authors evaluated and attempted to quantify the effects of respiratory movement and parallax. PATIENTS AND METHODS: After placement of an IVC filter, radiographs of the abdomen were taken at maximum inspiration and maximum expiration in 30 patients. The effect of parallax on apparent filter movement was studied by using a phantom. RESULTS: The average filter movement on inspiration/expiration radiographs (corrected for magnification) was 3.6 mm +/- 2.2. An 8.5-mm maximal change secondary to parallax was seen in the phantom study. CONCLUSION: When follow-up images are obtained, efforts should be made to closely reproduce patient positioning and patient respiration to reduce errors in the interpretation of filter migration.     

莱钢焦化厂生物脱氮系统优化实践

莱钢焦化厂1#生物脱氮系统在运行过程中存在污泥脱水效果差、加碱成本高、二沉池污泥上浮等问题,通过实施带式浓缩压滤机代替螺压脱水机、液碱代替纯碱、刮泥机改造等技术措施,解决了上述问题。系统优化后运行稳定,沉降比由60%～70%降至20%～40%,加碱成本降低了38%,出水悬浮物由90mg/L降至30mg/L。     

Research and practice on the vacuum filter in emulsion system for tandem cold strip mill

This paper introduces working principle and technical features of vacuum filter in emulsion system for tandem cold strip mill.Based on specific cases,this paper analyses and assesses the effect before and after using the emulsion system with the usage of the vacuum filter for strip mill.Compare with the effect when using the first generation vacuum filter,the emulsion quality is improved significantly by using the second generation vacuum filter,which at the same time ensures steady operation of the rolling mill and surface quality of the mill products. As a result,investment and running costs are lowered,emissions of the waste emulsion are reduced,waste water treatment costs are reduced and so as the environmental pollution.It can be seen the second generation vacuum filter has obvious economic and environmental benefits.Therefor,it suggests that the filter should be used widely in the field of automotive,environmental protection rolling steel and nonferrous metals.     

一种对烧结金属纤维毡过滤等级划分的方法

本文主要研究一种用多次通过试验台对烧结金属纤维毡进行等级划分的试验方法,这种方法模拟了用纤维毡制作的滤芯在实际工况中的使用环境.多次通过试验台对试验过程的控制,将试验时间均分为10份,在相同的时间间隔里对粉尘的粒径、数量、滤芯压降、注入粉尘量进行检测,同时用计算机将每一个时间段采集到的数据进行处理,用过滤比、过滤效率、...