双相不锈钢成分、性能及析出相分析

叙述了常用的超级双相不锈钢的成分、耐蚀性和应用,分析了不同种析出相、有害相、点蚀当量值(PRE)及焊接对双相不锈钢组织和性能的影响,得出通过控制合金化成分,调整点蚀当量值,编制合理的热处理工艺,严格控制有害相析出,使两相比含量比值接近1,可获得良好耐蚀性、高强度和耐磨性的双相不锈钢。     

稳压并抑制谐波的新型电源

由于电网谐波污染严重，对谐波的抑制已成为供电部门的重要任务。文章介绍一种既能稳压又能抑制谐波的新型电源，它采用串联型有源电力滤波的方法，通过瞬态电压补偿后可得到纯净的三相正弦平衡电压。     

磷酸酯的单双酯比例与加脂性能

以十六醇和P2O5为原料,分别合成了三种单双酯比例不同的十六醇磷酸酯皮革加脂剂,通过应用实验对它们的加脂性能进行研究,确定了单酯和双酯分别在加脂中所起的作用。结果表明,双烷基磷酸酯酯含量高的磷酸酯能赋予皮革更好的柔软性能和防水性能,单酯会使皮革产生明显的增厚。     

Free energy barrier for compact chains escaping from a small sphere

In this paper, the process of compact polymer chains escaping from a small sphere to a large one in the view of thermodynamics is investigated in detail based on the pruned-enriched-Rosenbluth method (PERM), which is quite efficient for the three-dimensional polymers on the simple-cubic lattice. In our simulation, three representative states of a polymer chain during the escaping process are studied, and some statistical properties of the chain size and the chain shape, such as mean-square radius of gyration per bond 〈S²〉/N and the shape factor 〈δ^∗〉 are investigated. Our aim is to illuminate how the size and shape of the compact chains change during the escaping process. The changes of 〈S²〉/N and 〈δ^∗〉 are not monotone and it is due to the fact that the chain should stretch itself in the escaping process. In the meantime, some thermodynamic properties are also calculated here. The hole is designed to be small enough to allow only one monomer at a time and it thus reduces the number of allowed chain conformations and breaks contacts between monomers at the beginning of the process. Additionally, we discuss the free energy barrier per bond H₂ − H₁ = ΔH of a compact chain, and here H₂ is the maximum free energy per bond during the process and H₁ is the minimum one when the compact chain is within the small sphere. Averaging free energy barrier over chain length N is convenient for the comparison with different chain lengths. ΔH as a function of chain length N and radius r₁ of the small sphere is also studied and our result shows that ΔH for longer chains is lower means that it is relatively easier for each bond in longer chains to surmount the free energy barrier to escape. Some discussions about the self-avoiding walk (SAW) and swollen chains are also made for the comparison, and our results also show that the restriction of the small sphere on the SAW and the swollen chains is more effective because of their relatively looser intrinsic structure.     

纳秒激光微刻蚀取向硅钢的形貌特征及磁性能

为有效降低取向硅钢铁损、改善其磁性能，采用红外纳秒激光对取向硅钢进行微刻蚀试验。利用3D共聚焦显微镜、扫描电镜与能谱仪研究典型工艺参数下的硅钢表面烧蚀形貌特征及表面质量，利用铁损仪测试不同刻蚀参数下取向硅钢的铁损、相对磁导率等磁性能参数及动态磁滞回线，对比分析刻痕前后磁性能的变化行为、规律及磁滞特性。结果表明：激光刻痕后，硅钢的铁损、相对磁导率、矫顽力及剩磁等性能得到明显改善，铁损的改善表现在高磁感强度下、相对磁导率的改善表现在低磁场强度下，回线特性得到优化。扫描速度为800 mm/s、脉冲能量为0.25 mJ时，刻痕边界呈近似规则的“波浪线”，且刻痕表面质量较高，铁损降低高达11.6%、剩磁降低12.8%等；刻痕后相对相对磁导率明显提高，提高约为5.7%~15.16%，最大可达2.598×10⁴。激光频率与扫描速度的耦合关系是影响刻痕边界形状与磁畴细化效果的重要因素。     

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 文章对蜡源方波材料NbSe2晶体的制备及其电学特性进行综述，介绍了利用化学气相输运法制备NbSe2晶体。测试出NbSe2晶体的临界温度为7.2K，30 K附近发生CDW转变，出现了CDW和超导电性共存的现象，通过分析 NbSe2晶体的ρ T曲线和NbSe2晶体的XRD图谱，讨论了低温下NbSe2晶体的重入现象。     

反射衰减诊断激光光束的应用分析

介绍了普通光学元件反射诊断激光光束的应用,提出了利用平面平晶的平面反射进行光能衰减,详细论述了采用该方法进行光能衰减的可行性,分析了平面平晶反射衰减中反射光S偏振态和P偏振态能量的差异,对激光束诊断的影响和解决方法,结合半导体绿激光器的光束诊断进行了应用分析。实验证明,该方法结构简单、调整方便、误差小,利用普通平面平晶反射衰减即可满足激光强度的匹配要求,实现了待测激光束无失真取样,达到很好的测试效果。     

X-ray fluorescence spectrometry determination of open-hearth furnace slag by pressed powder briquetting

Chemical composition of open-hearth furnace slag isimportant for the metal and casting quality. The chemicalcomponents of slag need to be analyzed precisely andaccurately.For a long time the composition determination of slag ismade chemically, which involves complicated processes,long analytical cycle, high cost and tedious work. A greatmany successful applications of ores analysis by x-rayfluorescence spectrometry (XRF) have been reported[1-4].Powder-fused wafer is a sampling method used in…     

基于HSI颜色空间统计直方图的图像检索

给出了一种对图像的特征进行提取、分析并识别出一定形状及色彩差别的方法,主要目的是提取图像的颜色变化。首先是对采集到的彩色图像进行预处理．包括：图像的滤波、目标图像的定位等;然后采取了相应的图像颜色空间和识别算法,包括：图像颜色空间的变换、颜色量化、图像特征提取、识别算法。计算机仿真结果表明,该算法可行,并取得了较好的效果。     

动态文本流中的话题线索检测算法

针对动态文本流中的话题线索检测问题,提出一种基于语义相关度模型的话题线索检测算法。利用改进的语义相关度模型计算消息文本与话题线索之间的语义相关度,将消息划分至相应的话题线索。在真实数据集上的实验结果表明,与现有算法相比,该算法的F1测度值较高。