润滑系统在冶金设备中的应用与分析

根据冶金设备的特点,对工程中常用的双线干油集中润滑系统、油气润滑系统和智能润滑系统做了详细的介绍和分析。考察和调研目前已投产的多家钢厂润滑系统的使用情况,结合参与炼钢项目润滑系统的设计经验,不仅从润滑系统的原理上进行比较,而且更注重从工程角度考虑,综合项目设计、成本和生产实践等方面进行了全面的比较,对以后钢厂建设中如何选用合理的润滑系统提供了依据和参考。     

基于工程设计的热轧宽厚板轧制规程计算系统的开发及应用

结合宽厚板轧机生产工艺特点及工程设计需要,开发了宽中厚板轧制规程计算软件,对宽厚板轧机轧制过程温度及力能参数计算模型公式的选用、计算方法及编程过程等进行了介绍。采用本软件计算的宽厚板轧制规程实例与工厂实际生产过程轧制规程进行了对比,两者计算结果比较一致。在现代宽厚板轧机工程设计中,采用该软件可获得合理准确的轧制规程,在轧机设备选型、轧机产能计算、极限规格产品轧制能力及轧机电气传动系统设计方面均具有重要的意义。     

武钢8号高炉炉体系统设计特点

对武钢8号高炉炉体系统的设计进行总结,根据武钢现役高炉的设计和生产经验,对现役高炉存在的问题和原因进行了分析,对8号高炉炉体系统的设计方案进行了论证和优化。     

液压扒渣机的结构分析与控制

针对恶劣工况及作业要求对液压扒渣机的倾翻、扒渣、液压控制进行了剖析和探究,对典型液压扒渣机在实际使用过程中的优缺点进行了分析。设计了一种液压扒渣机结构和控制系统,解决了扒渣机倾翻的同步问题,提高了扒渣机的稳定性、承载能力和适用范围,降低了扒渣机因烟尘污染、热变形和冲击负载导致的故障,实现了扒渣机的精确控制。     

宝钢二次冷轧切水及轧辊冷却技术研究

充分考虑到二次冷轧(DCR)机组生产特点,从设备与工艺两个方面入手,兼顾到带钢的表面质量与板形控制,开发出一套新型切水装置与喷淋控制工艺,形成了一套完整的轧辊喷淋冷却控制新技术,消除了原设计因使用挤干辊组进行"切水"的弊端,在保证了带钢表面质量的同时也提高了成品带钢的板形精度,并将其推广应用到宝钢DCR机组,大大降低了机组的板形与表面缺陷封闭率,取得了良好的经济效益。     

钢水脱气用真空泵系统的选择

干式机械真空泵(MVP)在钢水脱气工艺中的应用在过去10年间取得了巨大进展,但主要局限在炉容小于150t;推广到更大炉容的工作正在进行中。因为有蒸汽来源,蒸汽喷射真空泵(SVP)主要用于联合钢厂150～350t的大炉容。除了投资和运行成本方面的考虑,所有真空工艺和设备类型都能够不受限制地使用任何类型的现代真空泵系统。这2种系统都能够满足全部的冶金要求。由于MVP系统的运行成本明显降低,所以有必要重新审视在减少漏气、使用保护气体和降低泵组与冶金反应罐间压力损失等方面的努力。这2种系统的能效都得到了提高,但MVP的能源优势更为明显。在对真空泵系统进行比较时,应当只考虑总成本,包括为满足排放限制和安全标准的要求而必须付出的成本以及反应罐内的压力。此外,还应当重新考虑除尘系统的类型和使用,因为它们能够通过减少清理次数、节省用水、减少淤泥处理、降低SVP系统的设计抽气能力来显著降低成本。在同基于体积流量的MVP比较前,需要利用一个特殊的系数对SVP的质量流进行修正。根据所选泵需要的工作压力,MVP系统能够以明显低于SVP系统的质量流在反应罐达到同样的性能。     

高速钢轧辊在马钢CSP前机架应用研究

本文针对马钢CSP轧机的工作辊不均匀磨损严重影响出口板形质量的问题,对CSP轧机F3~F4不均匀磨损严重进行了分析,指出了使用高速钢轧辊的必要性。对高速钢轧辊的使用情况进行了大量的试验研究,并通过现场实际数据分析了高速钢轧辊情况下轧制力、轧辊温度、氧化膜情况,在大量现场试验的基础上制定了马钢CSP高速钢轧辊的使用工艺,并实现了工艺条件的长期稳定使用,通过现场实绩表明,使用高速港轧辊大大改善了机组的不均匀磨损,提高了机组的板形质量。     

转炉钢渣中磷元素的分布

转炉钢渣中的磷是影响钢渣在钢铁企业内部循环的主要因素之一。研究显示，如文献中对缓冷钢渣的研究结果一样，工厂稳定化处理后的转炉钢渣中的磷主要以磷酸三钙与硅酸二钙形式的固溶体存在。该固溶体在钢渣中呈不规则颗粒状，在钢渣的其它矿物相中没有发现磷元素。其实验结果与利用Factsage软件进行的热力学平衡计算结果相一致，说明对钢渣样的分析具有代表性。此结果为转炉钢渣中磷的综合利用和转炉钢渣在钢铁企业的再生利用打下良好基础     

炼钢多流仿真系统的设计与开发

炼钢多流仿真系统是可为用户提供"物质、能量、成本"一体化优化的炼钢生产整体解决方案的辅助工具。在确定系统的设计目标和设计原则基础上,设计和开发了炼钢多流仿真系统,并详细介绍了该系统的总体结构、功能模块和计算流程。以某钢厂生产条件为输入进行了实例仿真,验证了仿真系统的有效性,该系统可向用户提供物流、能量、成本相关指标的分析,用于辅助炼钢生产管理决策。     

立式连续退火炉预热段带钢加热温度分析计算计

本文针对实际生产中使用的带钢立式连续退火炉，建立了预热段(JPF)带钢温度计算公式。根据冲击射流对流换热原理和预热段的喷孔阵列形式，采用生产实测数据，模拟推导出对流换热努塞尔数计算公式。按照这组公式编制成MATLAB软件，计算结果与52组生产数据相符。该组计算公式和方法，可为带钢连续退火炉工程项目设计与应用提供一定的计算依据。     

A canine ex vivo shunt for isotopic hemocompatibility evaluation of a NHLBI DTB primary reference material and of a IUPAC reference material

Factors determining the thrombogenic response to particular artificial surfaces were investigated ex vivo in a canine shunt model. Methods using radioisotopic tracers made it possible to dynamically monitor the deposition of labelled blood cells and proteins on a NHLBI.DTB primary reference material polydimethylsiloxane (PRM.PDMS) and on a IUPAC reference material polyvinyl chloride (IUPAC.PVC). On the one hand, leukocyte affinity tau s(leu) (number of deposited leukocytes mm-2s-1) was not significantly different between IUPAC.PVC (tau s(leu) = 1.2-2.5) and PRM.PDMS (tau s(leu) = 1.5-3.4) and the fibrinogen adsorption rate varied from 33 to 48.10(-5) micrograms mm-2s-1 for both these materials. On the other hand, platelet affinity tau s(plat) (number of deposited platelets mm-2s-1) was significantly different (p < 0.05) for IUPAC.PVC and PRM.PDMS (tau s(plat)PVC = 683 +/- 200 > tau s(plat)PDMS = 327 +/- 80). Scanning electron micrographs of adherent platelets, red cells and leukocytes after blood contact ex vivo were performed after each experiment. This preliminary work contributes not only to quantify the adsorption of different radiotracers, but also to evaluate the superficial distribution of the labelled biological species on the inner surface of the tested biomaterials.     

Clocks regulating developmental processes

The goal of this study was to investigate the role of chronic otitis media with effusion as a cause of childhood imbalance. Nineteen 4- to 6-year-old children with chronic otitis media with effusion and 14 matched control children underwent a series of laboratory tests, including two standardized tests of balance and locomotion: the Peabody Developmental Motor Scales (PDMS) and the Bruininks-Oseretsky Test of Motor Proficiency (BOTMP). The children in the chronic otitis media with effusion group underwent tympanostomy tube insertion. Both groups underwent the same battery of tests within 6 to 8 weeks of initial testing. Analysis of variance for the PDMS and BOTMP demonstrated significantly lower performance in the balance subscales for the otitis group before (P < .01). Both otitis and control groups improved when retested. The improvement was greater and approaching significance in the otitis group on the PDMS and BOTMP (P = .056 and .097, respectively). It is concluded that chronic otitis media with effusion significantly affects balance and coordination skills in 4- to 6-year-old children. These skills improve after tympanostomy tube insertion at a rate greater than that of the control group.     

Novel functional polymers: poly(dimethylsiloxane)-polyamide multiblock copolymer. V. The interaction between biomolecules and the surface of aramid-silicone resins

Multiblock copolymers consisting of aromatic polyamide(aramid) and poly(dimethylsiloxane) (PDMS) aramid-silicone resins (PASs) were synthesized by low temperature solution polycondensation, and PAS films were prepared by casting from an N,N'-dimethylacetamide solution. In this study, we investigated bovine serum albumin (BSA) adsorption, L929 cell adhesion, and tissue reaction on the surface of PAS in order to clarify the interaction between PAS and biomolecules. It was found that the amount of adsorbed biomolecules on PAS was extremely low in contrast with those on aramid and nylon films, and it was comparable to SILASTIC 500-1 film. This suppression of adsorption of biomolecules onto PAS seemed to be due to the low surface free energy of the outermost surface of PAS, where PDMS block was condensed.     

Gas transfer and in vitro and in vivo blood compatibility of a fluorinated polyimide membrane with an ultrathin skin layer

The authors have synthesized fluorinated polyimides to develop a novel membrane oxygenator combining excellent gas transfer and blood compatibility. Gas exchange membranes of fluorinated polyimides prepared by a dry/wet process showed an asymmetric structure and consisted of an ultrathin and defect-free skin layer supported by a porous substructure. The asymmetric polyimide membranes never incurred plasma leakage because of the defect-free skin layer of the membrane surface. The calculated, apparent defect-free skin layer thickness of the asymmetric membrane was approximately 20 nm. Carbon dioxide and oxygen transfer rates through the membranes were dramatically enhanced because of the ultrathin skin layer and were 96 and 64 times larger than those determined in currently available oxygenator polymer membranes, such as polydimethylsiloxane (PDMS). For the evaluation of in vitro blood compatibility, platelet adhesion and plasma protein adsorption on the polyimide membranes were measured by using scanning electron microscopic examination and an amino acid analyzer. Deformation and aggregation of platelets adherent to the membranes were not observed, and the number of platelets was 1.6 micrograms/cm2, which was one-sixth less than the value measured in PDMS. For in vivo evaluation, the polymer tubes were implanted in the femoral vein of a mongrel dog for 7 days. Thrombus formation and fibrin were found on the surface of PDMS. However, thrombus formation was not observed on the polyimide. These results indicate that the fluorinated polyimides show excellent blood compatibility and are a promising membrane material for an oxygenator.     

In vivo biocompatibility and biostability of modified polyurethanes

Modified segmented polyurethanes were examined for biostability and biocompatibility using an in vivo cage implant system for time intervals of 1, 2, 3, 5, and 10 weeks. Two types of materials were used: polyether polyurethanes and polycarbonate polyurethanes. Two unmodified polyether polyurethanes (PEUU A' and SPU-PRM), one PDMS endcapped polyether polyurethane (SPU-S), and two polycarbonate polyurethanes (SPU-PCU and SPU-C) were investigated in this study. Techniques used to characterize untreated materials were dynamic water contact angle, stress-strain analysis, and gel permeation chromatography. Cellular response was measured by exudate analysis and by macrophage and foreign body giant cell (FBGC) densities. Material characterization, postimplantation, was done by attenuated total reflectance-Fourier transform infrared spectroscopy (ATR-FTIR) in order to quantify biodegradation and scanning electron microscopy (SEM) to qualitatively describe the cellular response and biodegradation. The exudate analysis showed that the acute and chronic inflammatory responses for all materials were similar. Lower FBGC densities and cell coverage on SPU-S were attributed to the hydrophobic surface provided by the PDMS endgroups. The polycarbonate polyurethanes did not show any significant differences in cell coverage or FBGC densities even though the macrophage densities were slightly lower compared to polyether polyurethanes. By 10 weeks, biodegradation in the case of PEUU A' and SPU-PRM was extensive as compared to SPU-S because the PDMS endcaps of SPU-S provided a shield against the oxygen radicals secreted by macrophages and FBGCs and lowered the rate of biodegradation. In the case of polycarbonate polyurethanes, the oxidative stability of the carbonate linkage lowered the rate of biodegradation tremendously as compared to the polyether polyurethanes (including SPU-S). The minor amount of biodegradation seen in polycarbonate polyurethanes at 10 weeks was attributed to hydrolysis of the carbonate linkage.     

Determination of cannabinoids in water and human saliva by solid-phase microextraction and quadrupole ion trap gas chromatography/mass spectrometry

Solid-phase microextraction (SPME) is applied to the determination of cannabidiol, delta 8-tetrahydrocannabinol (delta 8-THC), delta 9-tetrahydrocannabinol (delta 9-THC), and cannabinol in pure water and human saliva. The inherent extraction behavior of the cannabinoids in pure water is evaluated along with optimization of the method in human saliva. The commercially available poly(dimethylsiloxane) (PDMS) SPME fibers were found to be the best class for the cannabinoid analysis. Partition coefficients were found to be extremely large for all of the cannabinoids (log K > 4.0). Equilibrium times for the 7- and 30-micron PDMS fibers were 50 and 240 min, respectively. A shorter extraction time of 10 min with the 30-micron PDMS fiber may be used for multiple extractions from the same vial, thus conserving the sample necessary for analysis and speeding up the total analysis time. Recoveries for the cannabinoids in saliva, relative to pure water, were dramatically improved by a method developed in our laboratory involving addition of glacial acetic acid to the sample vial prior to performing SPME. Using this method, recoveries relative to SPME in pure water ranged from 21 to 47% depending on the cannabinoid. The linear range for spiked saliva samples was established at 5-500 ng/mL (r2 > 0.994) with precisions between 11 and 20% RSD. The ultimate level of detection by SPME for the cannabinoids in saliva was 1.0 ng/mL, with signal-to-noise values of > or = 12. A saliva sample collected 30 min after marijuana smoking was subject to SPME and traditional liquid-liquid extraction analysis. Internal standard quantitation results for delta 9-THC by both methods yielded comparable results, indicating that the SPME method of analysis is highly accurate and precise. The level of delta 9-THC by SPME was found to be 9.54 ng/mL for the saliva sample.     

铜阳极泥脱硒的工艺探讨及设计研究

探讨了从铜阳极泥中脱硒的主要工艺,重点阐述回转窑蒸硒工艺,包括工艺流程、主要设备选型,并结合目前国内工业生产实践及工程设计经验,优化设计。     

设计单位如何进行限额设计

针对设计工作中，开展限额设计的意义，以及实施的几个方面进行了论述。     

厨房整体设计在住宅建设中的应用

本文拟从住宅厨房整体设计中的设计目标，管线综合，柜体储物三方面进行初步探讨。     

Considerations for Design Criteria for Lunar Structures

The development of design criteria for lunar structures must begin soon in order to establish adequate criteria. Some of the items that need consideration in such criteria are discussed. The categorization of the structures will provide designers with information on the purpose and level of complexity of the structure. Various construction materials and structure types that will be critical for the design of lunar structures, are considered. The environment of the moon and its possible effects on structures are presented and lead to the development of a few load cases that need to be considered in design. A probabilistic format for the criteria and design lifetimes are also discussed.