Effects of rare earth on inclusions and corrosion resistance of 10PCuRE weathering steel

The types,morphologies and distributions of nonmetallic inclusions in Cu-P weathering steels with and without rare earth were analyzed through a quantitative image analyzer,scanning electron microscopy(SEM)and energy dispersive spectroscopy(EDS)attached to SEM.Solid-soluble content of rare earth in the steels was analyzed by non-aqua electroanalysis and ICP.The results showed that rare earth modified the types and the morphologies of inclusions in the weathering steels.The small spherical rare earth oxysulfides and rare earth sulphides replaced the elongated MnS inclusions in the RE weathering steels.The rare earth inclusions dispersedly distributed and most inclusions were smaller than 2 μm in size.The optimum content of RE was 0.0065%-0.016% for 10PCuRE weathering steels containing about0.002% oxygen and 0.004% sulfur.Solid-soluble content of rare earth in steels was(14-20)x 10-6,which can act as a micro-alloying element.The corrosion resistance of 10PCuRE weathering steels and Q235 were studied by dry-wet cyclic immersion test.Their corrosion rates were obtained respectively.The polarization curves and pitting corrosion behaviors of weathering steels with and without rare earth were measured by electrochemical methods.The corrosion resistance of Cu-P weathering steels was improved by adding an appropriate amount of rare earth.Less and fewer rare earth inclusions largely decreased pitting susceptibility and rate of pit propagation.The pitting potential and the resistance against pitting corrosion of the RE weathering steel were significantly improved due to the modification of rare earth to inclusions.     

Lanthanide NIR luminescence for telecommunications, bioanalyses and solar energy conversion

Present-day advanced technologies heavily rely on the exciting magnetic and spectroscopic properties of lanthanide ions. In particular, their ability to generate well-characterized and intense near-infrared (NIR) luminescence is exploited in any modern fiber-optic telecommunication network. In this feature article, we first summarize the whereabouts underlying the design of highly luminescent NIR molecular edifices and materials. We then focus on describing the main trends in three applications related to this spectral range: telecommunications, biosciences, and solar energy conversion. In telecommunications, efforts concentrate presently on getting easily processable polymer-based waveguide amplifiers. Upconversion nanophosphors emitting in the visible after NIR excitation are now ubiquitous in many bioanalyses while their application to bio-imaging is still in its early stages; however, highly sensitive NIR-NIR systems start to be at hand for both in vitro and in vivo imaging, as well as dual probes combining magnetic resonance and optical imaging. Finally, both silicon-based and dye-sensitized solar cells benefit from the downconversion and upconversion capabilities of lanthanide ions to harvest UV and NIR solar light and to boost the overall quantum efficiency of these next-generation devices.     

Evaluation of D113 cation exchange resin for the removal of Eu(Ⅲ) from aqueous solution

Batch adsorption experiments were conducted for the adsorption of Eu(Ⅲ) ions from aqueous solution by D113 resin. The results indicated that D113 resin could adsorb Eu(Ⅲ) ion effectively from aqueous solution. The adsorption was strongly dependent on pH of the medium with enhanced adsorption as the pH turned from 3.50 to 7.00 and the optimal adsorption condition was in HAc-NaAc medium with pH value of 6.50. The maximum uptake capacity of Eu(Ⅲ) ions was 290.9 mg/g D113 at 298 K, at an initial pH value of 6.50. The overall adsorption process was best described by Lagergren-first-order kinetics. When Freundlich and Langmuir isotherms were tested, the latter had a better fit with the experimental data. The thermodynamic parameters such as free energy (G) which were all negative, indicated that the adsorption of Eu(Ⅲ) ions onto D113 resin was spontaneous and the positive value of enthalpy (H) showed that the adsorption was endothermic in nature. Thomas model was applied to experimental column data to determine the characteristic parameters of column useful for process design. Furthermore, Eu(Ⅲ) could be eluted by using 3.0 mol/L HCl solution and the D113 resin could be regenerated and reused.     

Phase structure and temperature dependent luminescence properties of Sr2LiSiO4F: Eu2+ and Sr2MgSi2O7: Eu2+ phosphors

Green-emitting Sr2LiSiO4F:Eu2+ and blue-emitting Sr2MgSi2O7:Eu2+ phosphors were synthesized by the conventional high temperature solid-state route,respectively.Their structures and photoluminescenee properties were comparatively investigated.It was found that the mixture phases of Sr2MgSi2O7 and SrF2 were obtained when a part of Sr2+ in Sr2LiSiO4F was replaced by some amount of Mg2+ in order to design the possible SrMgLiSiO4F:Eu2+ phosphor.Based on the photoluminescence analysis,Sr2LiSiO4F:Eu2+ phosphor exhibited a green broad emission band of main peak at 513 nm under the excitation of 365 nm,while the Sr2MgSi2O7:Eu2+ and SrMgLiSiO4F:Eu2+ phosphor showed blue emission centered at 467 nm.The temperature dependent photoluminescence properties and room temperature decay time for the three kinds of phosphors were also discussed in this paper.     

Er3+-substituted W-type barium ferrite: preparation and electromagnetic properties

Er3+-substituted W-type barium ferrites Ba1-xErx(Zn0.3Co0.7)2Fe16O27(x=0.00,0.05,0.10,0.15,0.20)were synthesized by polymer adsorbent combustion method.Samples were characterized by X-ray diffraction analysis(XRD),X-ray fluorescence(XRF),scanning electron microscopy(SEM)and network analyzer to investigate the relationships among Er3+concentration,crystal structure,surface mcrphology and electromagnetic properties.All the XRD patterns showed pure phase of W-type barium ferrite when x≤0.15,while the impurity phase of ErFeO3 appeared when x=0.20.The pure W-type barium ferrite showed a hexagonal flake shape.In addition,the microwave electromagnetic properties of samples were analyzed in the frequency range of 2-18 GHz.It was indicated that the electromagnetic properties were significantly improved when Er3+doping content was 0.10.The reasons were also discussed using electromagnetic theory.The optimized ferrite exhibited excellent microwave absoption performance.The maximum of reflection loss(RL)reached about-27.4 dB and RL was below-10dB at the frequency range from 8.4 GHz to 18 GHz,when the thickness was 2.6 mm.     

EXAFS investigation and luminescent properties of nanosized Tb: Lu2O3 phosphors

Nanosized terbium doped Lu2O3 phosphors were synthesized via a modified co-precipitation processing.The as-prepared Tb:Lu2O3 phosphors was consisted of well crystallized nanosized sphere particles with a diameter of about 30 nnx Local structure of Tb ions in Lu2O3 lattice was investigated by an analytical approach based on Fourier transformation of the extended X-ray absorption fine structure(EXAFS) data.X-ray near edge structure (XANES) spectra suggested that all Tb ions doped were tervalonce.EXAFS results indicated that Tb ions have entered the Lu2O3 cubic lattice by means of solid solution.The coordination number and first shell Tb-O distance dropped with the increasing of Tb concentration.Emission spectra of the phosphors was shown to be typical for Tb3+ with main components at 542,550 and 490 nm,derived from irradiative relaxation of 5D4 level.The emission intensity decreased severely with the increasing of Tb concentration from 1 mol.% to 15 tool.%,suggesting a significant concentration quenching above 1 mol.% Tb.The reduction of emission intensity was interpreted by higher distortion derived relaxation among the surface state resident Tb3+ ions.     

Multi-Pass Simulation of Heavy Plate Rolling Including Intermediate Forced Cooling

Thermomechanical Controlled Processing (TMCP) including accelerated cooling after the final hot rolling pass is a well-established technology,widely applied in HSLA steel plate production.However,there are still certain limitations,especially for thicker plate.The rolling schedule includes a long holding period (HP) after the roughing stage to allow the temperature to fall sufficiently for optimised TMCP during finishing.Intermediate Forced Cooling (IFC) applied during the HP can increase productivity by decreasing the required hold time,can restrict austenite grain growth,and can also improve the subsequent strain penetration in thick plate with further metallurgical benefits.Multi-pass plane strain compression (PSC) tests have been performed on the thermomechanical compression (TMC) machine at Sheffield University including different severities of IFC.Clearly it is impossible to simulate all aspects of the temperature and strain gradients present in thick plates in laboratory specimens,and most of the tests were conducted at temperatures and strains calculated by Finite Element modelling as relevant to specific positions through the plate thickness.However,some aspects of the gradients were addressed with tests using cold platens.The results have indeed shown that IFC can shorten the HP and reduce austenite grain growth and its variation across thick plate.     

Overview of Particles and Bubbles in Continuously Cast Steel

This paper gives an overview of phenomena associated with particles and bubbles in continuously cast steel. During steel processing from deoxidation to solidification the inclusion population undergoes changes with opportunities of removal. Flotation is an important separation mechanism. Inclusion particles may accumulate in the solidifying strand, thus forming enriched bands, which depend on the type of casting machine. Bubbles are created during inert gas injection. They also change in size, can float out, but also form accumulation bands. The interaction of bubbles and particles is discussed. Internal structure that recently has been observed on the inner surface of bubbles will be reviewed.     

烦恼 快乐 艺术——池莉“人生三部曲”解读

池莉的"人生三部曲"--<烦恼人生>、<不谈爱情>、<太阳出世>诉尽了普普通通的市民烦恼,小说中主人公被柴米油盐、吃喝拉撒、老婆孩子等琐事所烦着,从而构成他们的"烦恼人生".然而池莉通过自己的艺术创作,以积极的人生态度,又让读者体会到生活本身的快乐,"烦恼人生"中包含着"快乐人生".     

属性块在工程图形中的研究与应用

介绍了在工程图形中用属性块标注表面粗糙度的方法.采用属性块不仅能避免大量重复性的工作,还能节省大量的存储空间,具有提高绘图速度、质量,便于修改,资源共享等应用价值.     

钛渣酸解过程中物相变化特征探讨

明确物相变化是剖析钛渣酸解机理和改进酸解工艺的关键点之一.综合应用化学分析、X射线衍射(XRD)分析、矿物解离分析以及扫描电镜形貌分析对某74钛渣酸解过程中主要物相的含量、形貌变化以及Ti、Si两种元素的含量及赋存变化进行了研究.结果表明:钛渣主要由黑钛石和辉石组成,酸解过程中黑钛石含量逐渐减小,辉石含量逐渐增加;反应...     

2004年铁合金市场回顾与2005年展望

2004年国际和国内铁合金价格波动较大，全年价格总体水平较往年有较大增长。2004年我国铁合金行业产销两旺，全年产量和出口量均创历史新高，市场价格较往年也有明显改善。但是，铁合金行业发展过热已引起国家有关部门和业界的高度重视，并相继出台了一系列相关的产业政策和调控、指导性措施，对整个铁合金行业的发展产生了深远影响。文章从生产、消费及进出口等方面对2004年中国铁合金市场进行了分析并对2005年市场前景进行了预测。     

Design and optimisation of charging ingredients and structure in an ironmaking system (Part II)

In order to maximise the reduction of pig iron cost in an ironmaking process, and at the same time ensure the output and quality of the pig iron, a design and optimisation system for the charging ingredients and structure in an ironmaking system was established using metallurgical theory. The system includes six modules, namely, sinter metallurgical performance testing and analysis, sintering burdening design, sinter component and property prediction, blast furnace burdening design, blast furnace batching calculation and ironmaking system burden optimisation. Based on actual production, testing and material balance theory, the system integrated these modules on VB and MATLAB using a series of intelligent algorithms, such as the BP neural network, multiple objective linear programming, genetic algorithms and so on. As a result, the optimum burden composition and structure of the sinter and blast furnace that satisfied all the constraint conditions could be obtained. Standing as a pinnacle of the global ironmaking production, the system can design and optimise not only the sintering burden, but also the blast furnace burden. Compared with the traditional production testing and hand calculation in the ironmaking system, the project can greatly reduce the production risk and greatly increase the calculation accuracy. Industrial application shows that the system is especially beneficial to reduce the ironmaking cost and at the same time ensure the output and quality.     

长流程钢铁企业检化验设施的现代化设计

检化验系统对钢铁企业的进厂原料检验、中间产品检测、出厂产品质量判定等有着重要意义。对钢铁企业检化验系统的设置原则、组成和发展趋势进行了介绍,集中化、智能化和信息化是现代化钢铁企业检化验系统的特点。重点论述了原料取制样系统、原料分析中心、冶炼分析中心和轧钢检测中心的建设设计理念。随着中国智能制造发展,全自动智能检测系统、信息流过程自动化及实验室管理自动化已成为当今钢铁企业检化验系统设计不可避免的趋势。     

Lunar Astronomical Observatories: Design Studies

The best location in the inner solar system for the grand observatories of the 21st century may be the Moon. A multidisciplinary team including university students and faculty in engineering, astronomy, physics, and geology, and engineers from industry is investigating the Moon as a site for astronomical observatories and is doing conceptual and preliminary designs for these future observatories. Studies encompass lunar facilities for radio astronomy and astronomy at optical, ultraviolet, and infrared wavelengths of the electromagnetic spectrum. Although there are significant engineering challenges in design and construction on the Moon, the rewards for astronomy can be great, such as detection and study of Earth‐like planets orbiting nearby stars, and the task for engineers promises to stimulate advances in analysis and design, materials and structures, automation and robotics, foundations, and controls. Fabricating structures in the reduced‐gravity environment of the Moon will be easier than in the zero‐gravity environment of Earth orbit, as Apollo and space‐shuttle missions have revealed. Construction of observatories on the Moon can be adapted from techniques developed on the Earth, with the advantage that the Moon's weaker gravitational pull makes it possible to build larger devices than are practical on Earth.     

热轧不锈钢板酸洗工艺

为去除热轧不锈钢板表面的氧化层与贫铬层,钝化基体,改善表面质量,在热轧退火后需进行酸洗处理。介绍了热轧不锈钢板表面氧化层和贫铬层的组成与结构特征及其对酸洗过程的影响,并对热轧不锈钢板的酸洗体系设计和酸洗工艺开发进行了阐述。中国热轧不锈钢板普遍采用前处理(机械除鳞、中性盐电解等)→硫酸(电解)预酸洗→硝酸-氢氟酸终酸洗的酸洗工艺,旨在通过前处理和预酸洗去除大部分的氧化层,在终酸洗阶段去除残余氧化层及贫铬层,同时实现基体钝化。目前,热轧不锈钢板的酸洗工艺存在酸洗效果不稳定、贫铬层去除不完全、局部腐蚀较为严重等问题,且会产生不同程度的环境污染问题。应该根据不同钢种不同退火工艺条件下的表面氧化层与贫铬层的性质与分布特征,研究开发相应的酸洗体系和酸洗工艺。热轧不锈钢板的环保型酸洗新工艺具有广阔的发展前景。     

Impressions of psychotherapists' offices.

For counseling settings, research suggests that softness, personalization, and order might affect the experience and the perceived expertness, trustworthiness, and social attractiveness of the therapist. This article discusses exploratory studies on college students' perception of the counseling office environment and whether the likely client experience was associated with the softness/personalization and order of the office. As stimuli, the studies used 30 color photographs of psychotherapists' offices viewed from the client's perspective. After obtaining ratings of the characteristics of each office, we obtained ratings from different groups of students of the quality of care and comfort expected in each office (Study 1) and how qualified, bold, and friendly the therapist in the office would be (Study 2). Additional studies examined the likelihood of choosing a therapist based on the office, and the first thought or feeling that came to mind about the office, the therapist, and the patient experience. There were strong correlations in response between groups (by whether they had experienced therapy; their level in school; their gender; and their major, location, and school size). The quality of care, comfort, therapist boldness, qualifications of the therapist, and the likelihood that one would choose a therapist based on the office improved with increases in the office's softness/personalization and order. Friendliness improved with increases in softness/personalization. The office choices, open-ended responses, and reported reasons for the ratings confirmed the importance of softness (comfort) and order. Research should test longer term exposure and behavior. (PsycINFO Database Record (c) 2011 APA, all rights reserved)     

Simultaneous and Sequential Photosonolysis of TCE and PCE

Aqueous solutions of trichloroethylene (TCE) and tetrachloroethylene (PCE) were treated in a flow-through reactor equipped with ultrasound and ultraviolet light sources. The reactor was operated as sonolysis (US), photolysis (UV), and simultaneous photosonolysis (UV/US) reactors; then as US, UV, and sequential UV/US reactors with the installation of a partition in the reactor. The reactor without the partition was simulated by using one continuously stirred-tank-reactor (1-CSTR) model, and the reactor with the partition was simulated by using the sequential CSTR model. Through model calibration, the decomposition rate constants and reactor efficiencies for the removal of TCE and PCE were evaluated. The results suggest that the combined effect of UV and US on the decomposition of TCE and PCE is synergistic in both the simultaneous and sequential UV/US modes, that the rate constants of sonolysis and photolysis are greater with the sequential combination than with the simultaneous combination, and that overall efficiency is higher for the reactor with the partition than for the one without it.     

浅谈加强建设工程招投标管理工作的重要性

对于建设工程的招标人来说,重要的是如何找到理想的、有能力承担建设工程任务的合格单位,用经济合理的价格,获得满意的服务和产品。根据建设工程的通常做法,建设工程的招标人均是严格按照法律法规的规定,通过招投标形式选择建设工程任务的实施单位,包括设计、监理、施工承包和供货等单位。可见利用招投标形式选择合格的实施单位,一方面从法律上保证了项目和项目法人的合法性,另一方面,也从技术上和经济上为项目的顺利实施提供了支持和保障。     

History of psychology.

If we accept philosophy as the search for knowledge about ourselves and the world around us by reasoning and we accept psychology as the use of science in the search for understanding the mind and behavior, we can get along without philosophy in our history courses very well. We can begin the history of psychology with the emergence of the life sciences in the early 1800s with passing kudos to the general emergence of science via Gallileo, Newton and Bacon. We can sanitize Fechner, Wundt, James and Dewey; ennoble Pavlov, Watson and Skinner; plunge into learning and psychobiology (while sanctifying logical positivism); and end amidst computers and cognition. And remain unscathed and untouched by human (and humane) reasoning and philosophy. Overall, from the perspective of a historian type, I am less and less certain about the present or the future without the sifting wisdom of history. (PsycINFO Database Record (c) 2010 APA, all rights reserved)