1422热轧卷形出边的原因分析及对策

梅钢热轧卷3．0I-tim以下的薄规格卷形因内圈、外圈出边在经过运输、压头及入库过程中，容易因挤压、碰撞而造成边部折迭，产生质量损失。通过长期的观察和研究，着重分析内圈、外圈出边产生的原因，总结了一套控制和减少卷形出边的方法。

镁合金射出模压成形技术

论述了镁合金的优良特性及其应用领域不断扩大的现状;介绍了国外开发的镁合金射出模压成形机及其成形工艺的特点,以及用该技术生产的产品实例。

低压田间出水柱形回转阀门的研究

针对田间低压供水平板闸阀开启速度慢和球阀开启阻力大等问题,研究出低压田间出水柱形回转阀门,采用圆柱形内外壳体间隙配合、J型无骨架橡胶密封圈密封和可快速拆装式启闭手柄等关键技术,其结构简单,操作方便,能降低成本,提高生产效率。研究内容可为农田水利灌溉措施提供一种新思路。

浅谈《三国演义》中人物的出场式

《三国演义》中人物的出场方式,大致可分为“自出”和“引出”两种。自出式是让人物直接出场、通常不依赖于外部场景的描绘,不依赖气氛的烘托,不借助于其他人物的语言和行动,而是让人物以自己独特的外形、语言、情绪和动作“自我表演”,因而它又可分为“形出”、“声出”、“声出形出结合”等几种。《三国演义》中,吕布、赵云、周瑜等人都采用了“形出”的出场方式:张飞、杨修 姜维、徐庶等人采用了“声出”的出场方式;关羽、魏延、孟获等人则采用了“声出形出结合”的出场方式。“引出”式往往要借助于某些“间接手段”,在做好了充分准备的基础上,让人物“应境而出”或“应运而出”。《三国演义》中,鲁肃、陆逊、马谡、诸葛亮等人的出场,都采用了“引出”式。人物的出场式受作品结构的制约、不同结构的文学作品,人物的出场方式不同。话本、戏曲和小说,在人物的出场方式上有着渊源关系。

不同压出室下叶轮切割对离心泵性能的影响

为研究2种不同压出室下叶轮切割对离心泵性能的影响,以及单级单个叶轮切割与多级下单个叶轮切割的差异,基于N-S方程、标准k-ε湍流模型和SIMPLE算法对MD-280-43×6型多级离心清水泵进行三维数值模拟.计算结果表明:以单级单个叶轮为切割目标时,随着切割量增大,螺旋形压出室的水力效率变化趋势比径向导叶式压出室的变化趋势更为明显,压水室水力损失每叶轮2%切割量,损失平均增长分别为0.360,0.193 m,2种压出室内部动压分布及对叶轮所产生径向力的变化趋势有明显差异;以多级下单个叶轮切割与单级单个叶轮切割的对比为目标时,对于径向导叶式压出室离心泵和螺旋形压出室离心泵,其水力效率、扬程、内部湍动能分布与各种单级单个模型平均偏差分别为1.644%,0.279%,2.090 m,1.573 m,1.302 J/kg,1.548 J/kg;不同压出室下叶轮切割特性的研究,应考虑压出室所带来的差异;多级泵叶轮切割特性研究时,应尽量回归多级环境进行研究.

Strengthening mechanism of T8-aged Al-Cu-Li alloy with increased pre-deformation

The microstructure evolution and mechanical properties of a T8-aged Al-Cu-Li alloy with increased pre-deformation(0-15%) were investigated,revealing the microstructure-strength relationship and the intrinsic strengthening mechanism.The results show that increasing the pre-deformation levels remarkably improves the strength of the alloy but deteriorates its ductility.Dislocations introduced by pre-deformation effectively suppress the formation of Guinier-Preston(GP) zones and provide more nucleation sites for T1 precipitates.This leads to more intensive and finer T1 precipitates in the samples with higher pre-deformation levels.Simultaneously,the enhanced precipitation of T1 precipitates and inhibited formation of GP zones cause the decreases in number and sizes of θ′ precipitates.The quantitative descriptions of the strength contributions from different strengthening mechanisms reveal that strengthening contributions from T1 and θ′ precipitates decrease with increasing pre-deformation.The reduced diameters of T1 precipitates are primarily responsible for their weakened strengthening effects.Therefore,the improved strength of the T8-aged Al-Cu-Li alloy is mainly attributed to the stronger strain hardening from the increased pre-deformation levels.

叶片泵螺壳式压出室内流动损失的分析计算

在一元流动理论基础上，根据螺壳式压出室的结构特点，对其中液体流动的物理过程和造成的水力损失进行了分析，并导出了部分计算模型。

末级压出室水力结构对多级离心泵水力性能的影响

为了研究压出室不同水力结构对节段式多级离心泵水力性能的影响,基于RNG k-ε湍流模型,对末级压出室采用环形结构和双蜗壳螺旋形结构的两组水力模型进行定常数值模拟,并对比分析了两组模型水力性能的变化。结果表明:螺旋形结构的扬程比环形结构高出了1.63%,轴功率比环形结构降低了10.62%,因而效率比环形结构提高了10.69个百分点;叶轮与导叶间的动静干涉作用是导致环形压出室水力性能明显下降的根本原因;节段式多级离心泵的末级压出室采用螺旋形结构,对提升整泵水力性能将产生积极的影响。

中国古代蚕形器物的文化研究(考古篇)

我国有大量历史遗存的蚕形器物,这是蚕桑丝绸数千年发展的历史见证,也是珍贵的文化遗产,然而针对蚕形器物文化属性、历史价值、艺术特征的系统性研究目前尚未展开。本文在收集整理相关文献资料和实物的基础上,就已出土的蚕形器物进行了较为系统的初步分析和开创性研究,提出了规范名称和分类;展示了部分出土蚕纹器和蚕形器的信息;同时从古代蚕形器物的产生年代、地域分布、形状特征、材料使用、实际用途和文化现象六个方面进行详细阐述,旨在挖掘蚕形器物的历史价值和文化内涵,弘扬传统文化。

Microstructure of asymmetric twin-roll cast AZ31 magnesium alloy

The microstructural distribution along thickness of asymmetric twin-roll cast AZ31 magnesium alloy slab was investigated. It was found that the microstructure along the thickness of the slab was significantly inhomogeneous. There were many deformed bands with flow form near the upper surface of twin-roll cast plate. Very few deformed bands could be seen in the central part of the plate where the dendrites were thick. Fine dendritic structures dominated near the lower surface of the twin-roll cast strip. It is concluded that the shear strain caused by linear velocity difference between surfaces of upper and lower rolls results in the deformed bands of the twin-roll cast slab. Aluminum, zinc and manganese segregate to the boundary of dendrites, while silicon distributes inside the α-Mg solid solution.

Effects of external stress aging on morphology and precipitation behavior of θ'' phase in Al-Cu alloy

The exposure of Al-5Cu alloy to an external stress with normal aging was carried out. The effects of external stress-aging on the morphology and precipitation behavior of θ＂ phase were investigated by transmission electron microscopy （TEM）, differential scanning calorimetry （DSC） and first principle calculation. The size of the θ＂ phase precipitated plates in stress-aging （453 K, 6 h, 50 MPa） is 19.83 nm, which is smaller than that of those present （28.79 nm） in stress-flee aging （453 K, 6 h）. The precipitation process of θ＂ phase is accelerated by loading external stress aging according to the analysis of DSC results. The apparent activation energy for the external stress-aging is 10% lower than the stress-free one. The first principle calculation results show that the external stress makes a decrease of 6% in the interface energy. The effects of the stress on aging process of the alloy are discussed on the basis of the classical theory. The external stress changes the morphology and precipitation behavior of θ＂ phase because the critical nucleation energy is decreased by 19% under stress aging.

低位直肠癌拖出式适形切除术肠壁侧切缘安全距离的初步探讨

目的：探讨低位直肠癌肠壁侧方浸润距离，为拖出式适形切除术（PTCR）肠壁侧切缘的安全距离提供理论依据。方法收集2015年12月至2016年3月期间在上海第二军医大学附属长海医院肛肠外科因直肠癌行低位前切除术（LAR）或经腹会阴联合切除术（APR）患者的手术标本，经10％甲醛固定24 h后，分别在肿瘤标本顺时针走行的3、5、7和9点处，以肿瘤边界为原点，向外呈辐射状切取长度为1．5 cm，宽度为0．5 cm大小的正常肠管全层组织，测量肿瘤侧方浸润的距离并分析其影响因素。结果共收集到83例手术标本，总体侧方浸润率为71．1％（59／83），其中3、5、7和9点处，侧方浸润率分别为34．9％（29／83）、26．5％（22／83）、32．5％（27／83）和37．3％（31／83），差异无统计学意义（字2＝2．4449，P＝0．4853）。肿瘤的3、5、7、9点侧方浸润距离的中位数（四分位间距）分别为0（1．00）、0（0．50）、0（0．55）及0（1．00） mm；4个点位的第5百分位数（P5）均为0 mm，4个点位的第95百分位数（P95）分别为2．5、1．6、2．6和2．5 mm，各点位间浸润距离差异无统计学意义（字2＝5．3310，P＝0．1489）。 T1、T2、T3和T4期肿瘤侧方浸润率分别为0／4、58．3％（14／24）、83．0％（44／53）和1／2，差异有统计学意义（P ＝0．0050）。多因素回归分析显示，肿瘤T分期是肿瘤发生侧方浸润的独立危险因素（P ＝0．0022， OR ＝3．741，95％ CI：1．606～8．716）。结论低位直肠癌存在肠壁侧方浸润， T分期是其独立危险因素；施行PTCR时肠壁的斜行切除线距肿瘤边缘至少5 mm可保证侧切缘阴性。

经肛门拖出式适形切除术治疗极低位直肠癌的临床研究

目的：探讨拖出式适形切除术治疗极低位直肠癌的手术安全性和可行性。方法2011年1月至2014年6月，上海第二军医大学长海医院肛肠外科对符合Rullier极低位直肠癌外科学分类标准Ⅱ、Ⅲ型的29例患者施行经肛门拖出式适形切除术。结果29例极低位直肠癌患者均顺利完成手术，均行预防性回肠造口术。术中出血（69．5±32．8） ml，手术时间（138．3±35．6） min。术后临床病理学结果：远切缘距离（0．6±0．3） cm，清扫肠系膜淋巴结（14．6±3．5）枚。本组无围手术期死亡病例，术后并发症4例（13．8％），1例发生胃排空障碍，2例发生骶前感染，1例发生吻合口瘘，均给予保守治疗包括抗感染及引流后痊愈。所有患者均接受随访，随访（2～46）月，2例（6．9％）发生远处转移，21例回肠造口还纳术的患者肛门功能恢复良好。结论经肛门拖出式适形切除术是一种治疗极低位直肠癌的保肛手术技术，可以获得安全的肿瘤远切缘距离。

A Fully Integrated CMOS Readout Circuit for Particle Detectors

Novel schemes for a charge sensitive amplifier （CSA） and a CR-（RC）, semi-Gaussian shaper in a fully integrated CMOS readout circuit for particle detectors are presented. The CSA is designed with poly-resistors as feedback components to reduce noise. Compared with conventional CSA, the input referred equivalent noise charge（ENC） is simulated to be reduced from 5036e to 2381e with a large detector capacitance of 150pF at the cost of 0.5V output swing loss. The CR-（RC）,semi-Gaussian shaper uses MOS transistors in the triode region in series with poly-resistors to compensate process variation without much linearity reduction.

Microstructural evolution of 2026 aluminum alloy during hot compression and subsequent heat treatment

2026 aluminum alloy was compressed in a temperature range of 300-450 ℃ and strain rate range of 0.01-10 s^-1. The correlation between compression conditions and microstructural evolution after solution and aging heat treatment was investigated. It is found that the recrystallization and precipitation behavior after heat treatment are associated with the temperature compensated strain rate Z value during hot deformation. Under low Z parameter condition, a small quantity of free recrystallized grains are formed, and the well formed subgrains with clean high-angle boundaries and coarse precipitates seem to be remained during heat treatment. Under high Z parameter condition, a large number of fine equiaxed recrystallized grains are produced, and a high dislocation density with poorly developed cellularity and considerable fine dynamic precipitates are replaced by the well formed subgrains and relatively coarse precipitates after heat treatment. The average recrystallized grain size after heat treatment decreases with increasing Z value and a quantitative relation between the average grain size and the Z value is obtained.

Effect of pre-deformation on microstructures and mechanical properties of high purity Al-Cu-Mg alloy

The effects of pre-deformation following solution treatment on the microstructure and mechanical properties of aged high purity Al-Cu-Mg alloy were studied by tensile test, micro-hardness measurements, transmission electron microscopy and scanning electron microscopy. The micro-hardness measurements indicate that compared with un-deformed samples, the peak hardness is increased and the time to reach peak hardness is reduced with increasing pre-strain. Additionally, a double-peak hardness evolution behavior of cold-rolled （CR） samples was observed during aging. The results of TEM observation show that the number density of S′（Al2CuMg） phase is increased and the size is decreased in CR alloy with increase of pre-strain. The peak hardness and peak strength of the CR alloy are increased because of quantity increasing and refinement of S′ phase and high density dislocation.

Iron L-edge and sulfur K-edge XANES spectroscopy analysis of pyrite leached by Acidianus manzaensis

Iron L-edge and sulfur K-edge X-ray absorption near edge structure（XANES） spectroscopy analysis of pyrite leached by extreme thermophilic Archaea strain Acidianus manzaensis（A.manzaensis） was carried out.Leaching experiments show that the oxidation of pyrite can be accelerated by A.manzaensis.Leaching results show that with the increase of leaching time,pH value in the leaching solution gradually decreases,redox potential increases rapidly from day 0 to day 3,and then increases slowly.The SEM results show that the pyrite surfaces are corroded gradually by A.manzaensis,and the XRD results show that the leaching residues contain new compositions of jarosite and elemental sulfur（S0）.The iron L-edge XANES spectroscopy analysis of pyrite during biooxidation indicates that pyrite is gradually converted to Fe（III）-containing species.The sulfur K-edge XANES spectroscopy analysis indicates that elemental sulfur is produced during bioleaching and maintains mass fractions of 3.2%-5.9%.Sodium thiosulfate was also detected from day 2 to day 4,indicating the existence of thiosulfate during biooxidation of pyrite.

The Teachers＇ Feedback Act Research of College English Classes

The Follow up Move Research has been deepening after it was first defined in 1975 by Sinclair and Coulthard, but it has not been paid attention in China, let alone study its effect in the classroom. In this essay based on the author＇s literature reading, the Follow up move functions and their language features are classified; its pragmatic motivations are researched and some factors which affect its relevance of occurrence are studied. Then with this guide of the frame four teachers classroom follow up moves are studied. Finally, the other scholars＇ findings in this field are commented and then the author＇s own insights are put forward.

Effects of hot compression on carbide precipitation behavior of Ni-20Cr-18W-1Mo superalloy

The effect of hot compression on the grain boundary segregation and precipitation behavior of M6C carbide in theNi-20Cr-18W-1Mo superalloy was investigated by thermomechanical simulator, scanning electronic microscope （SEM） and X-raydiffraction （XRD）. Results indicate that the amount of M6C carbides obviously increases in the experimental alloy after hotcompression. Composition analyses reveal that secondary M6C carbides at grain boundaries are highly enriched in tungsten.Meanwhile, the secondary carbide size of compressive samples is 3？5 μm in 10% deformation degree, while the carbide size ofundeformed specimens is less than 1 μm under aging treatment at 900 and 1000 ℃. According to the thermodynamic calculationresults, the Gibbs free energy of γ-matrix and carbides decreases with increase of the compression temperature, and the W-rich M6Ccarbide is more stable than Cr-rich M23C6. Compared with the experimental results, it is found that compressive stress accelerates theW segregation rate in grain boundary region, and further rises the rapid growth of W-rich M6C as compared with the undeformedone.

隔舌半径对单级双吸离心泵性能的影响

为了研究隔舌半径大小对单级双吸离心泵性能的影响,基于标准k-ε湍流模型和标准无滑移网格模型,应用Fluent软件对其不同工况下的定常流动进行三维数值模拟,得到不同工况下单级双吸离心泵蜗壳内部流道的流动特性。计算结果表明,对于提出的隔舌半径为6 mm、8 mm、10 mm的三种方案,当隔舌半径为8 mm时,泵扬程和效率在各工况点都较高,且效率在最优工况点高出2%。通过三种方案下内部流动特性的对比分析可得出隔舌半径为8 mm时,压出室内流动更稳定,隔舌处流速变化更小,流动损失也更小。由此可得,压出室圆角隔舌合理选择隔舌半径能够使单级双吸离心泵的性能更优。