球磨研磨对绿豆淀粉颗粒结构及性质的影响

为探究球磨研磨对绿豆淀粉颗粒结构及性质的影响,采用扫描电镜、偏关显微镜、X-射线衍射仪、傅立叶红外光谱仪等分析手段对研磨处理后绿豆淀粉的结构进行表征,确定淀粉颗粒形貌、双折射现象、晶体结构及分子特征的变化,并进一步对淀粉溶解度、膨胀度、持水能力及冻融稳定性等理化指标进行测定。结果表明,淀粉颗粒形貌变得粗糙不光滑,出现裂痕、缝隙、凹陷等形貌状态,淀粉颗粒粒度变大,颗粒大小不均一,形状极不规则,多呈扁平状,偏光十字消失;淀粉颗粒结晶结构被破坏,由多晶态向无定形态转变,呈现非晶化状态;粉碎过程淀粉无新的基团产生,淀粉颗粒由有序结构向无序化结构转变。微细化绿豆淀粉的溶解度、膨胀度随着温度的升高而增大,持水能力为原淀粉的3.2倍,且具有良好的冻融稳定性。

球磨研磨对荞麦淀粉结构及性质的影响

为探究球磨研磨对荞麦淀粉颗粒结构及性质的影响,采用激光粒度分析仪、扫描电子显微镜、X-射线衍射仪、差示扫描量热仪、快速黏度分析仪等先进仪器及分析手段研究球磨处理前后荞麦淀粉颗粒大小及分布、颗粒形貌、晶体结构、热力学性质及糊化特性的变化。结果表明,球磨研磨处理后淀粉颗粒粒径增大,平均径由11.99μm增大到18.52μm,粒径分布主要集中在10.0～45.0μm范围内;颗粒形貌由光滑颗粒变成粗糙不均颗粒,颗粒呈扁平状,颗粒晶体结构受到严重破坏,由多晶态向无定形态转变;淀粉热焓值及糊化温度下降,黏度值降低,球磨研磨荞麦淀粉具有良好的冷糊及热糊稳定性,可应用到高浓低黏体系中。研究为荞麦淀粉物理改性及技术应用提供理论指导和技术支撑。

球磨微细化研磨对发芽糙米粉物性特征的影响

以发芽糙米为原料,利用扫描电子显微镜(SEM)、傅里叶红外光谱(FTIR)等手段探究了微细化研磨处理对发芽糙米粉干燥前后微粒粒径、微观形貌特征、水合性能、蛋白二级结构特征的影响。结果表明,经球磨处理后,发芽糙米粉的粒径明显降低,淀粉颗粒形貌与晶体结构遭到破坏,部分微粒外壳坍塌,喷雾干燥后颗粒变得细小且均匀,小颗粒的团聚现象减少;球磨处理2 h和喷雾干燥处理后,总的水合性能显著增强;蛋白质结构更为伸展,受剪切力影响,淀粉有序结构遭到破坏。球磨研磨发芽糙米粉粒径微细且分布均匀,颜色更白,具有良好溶解性、分散性和口感,并且经过冲调后形成了具备良好黏弹性的米浆,研究为球磨研磨处理全谷物提供基础数据与参考。

球磨机研磨体快速分级装置应用实践

水泥行业的快速发展,使球磨机也不断向大型化和自动化方向发展,在磨机运行一段时间后,仓内的研磨体会出现磨损、变形、窜仓等现象,级配会发生变化,从而降低粉磨生产效率.介绍采用球磨机研磨体快速分级装置,将研磨体快速分级,有利于球磨机精准合理级配,有效解决现有技术中研磨体分级难题,使磨机研磨体及时合理级配,提高磨机的效能,减小劳动强度,提高工作效率,易于操作控制,具有很好的推广价值.

辊式磨及行星球磨对不同硬度小麦的淀粉损伤探析

采用3种不同硬度的小麦先经实验磨粉机研磨制粉，再将小麦粉与淀粉分别进行球磨研磨，探讨不同硬度颗粒在研磨粉碎过程中颗粒的粒度、表观特性、淀粉损伤程度等特性变化的一些基本规律。试验结果表明：使用辊式磨粉机研磨时，硬度较高的胚乳颗粒易造成淀粉损伤，扫描电镜图清晰地显示了磨辊在硬麦粉中较大颗粒的表层淀粉上留下的伤痕。

颗粒状冷水可溶玉米淀粉制备工艺优化与性质研究

采用球磨研磨法制备颗粒状冷水可溶玉米淀粉,在单因素试验基础上,采用Box-Benhnken中心组合试验及响应面分析法,优化制备工艺,并通过PLM、SEM和XRD等仪器分析其性质。结果表明最佳制备工艺条件为:球磨时间3.24 h,球磨机转速555 r/min,球料比6.52∶1,此时冷水溶解度的平均值可达到57.95%;淀粉颗粒表面变得粗糙,偏光十字消失,从多晶态转变成了非晶态,且淀粉糊浊度降低。

Mechanically activated disproportionation of NdFeB alloy by ball milling in hydrogen

Mechanically activated disproportionation of Nd 12 Fe 82 B 6 alloy by ball milling in hydrogen atmosphere was experimentally investigated. The aspects of thermodynamics and kinetics for the mechanically activated disproportionation of the NdFeB alloy were discussed. Both the evolution of the disproportionation reaction and the corresponding microstructure change of the alloy during milling were characterized by X ray diffraction (XRD) analysis. The results show that the matrix phase Nd 2Fe 14 B of the as cast Nd 12 Fe 82 B 6 alloy can be disproportionated into a mixture of Nd hydride (H 5Nd 2), FeB/Fe 2B, and α Fe, by ball milling under hydrogen pressure of 0.2 MPa. The as disproportionated phases are of the size about 20 nm, suggesting that ball milling in hydrogen is an effective route for low temperature disproportionation processing of the NdFeB alloy to ensure a full nano structured as disproportionated microstructure. This is the basis for synthesizing Nd 2Fe 14 B/ α Fe nano composites with magnetic exchange coupling effect by subsequent desorption recombination processing.

电瓷高效制浆法实现的可能性

电瓷工业中所用粘土类、长石类、矾土类、石英类等原料多已在原料厂经过了加工处理,电瓷的制浆工艺由研磨为主转变为以混合与研磨为主。对此,分析传统的以球磨机为主体设备的制浆系统的特点,并根据现场试验的结果,阐述了内循环高效研磨机的工作原理及以其为主体设备的电瓷新法制浆系统的构成,提出了制浆效率高、能耗小的新法制浆系统。实验表明,高强料的研磨工效是球磨机的25倍,釉料的研磨工效为球磨机的36倍,在电瓷工业中具有广泛的应用前景。

Mechanochemical-Assisted Leaching of Lamp Phosphors： A Green Engineering Approach for Rare-Earth Recovery

稀土元素(REE)是设计和开发可持续能源应用的重要金属。从富含稀土元素的废物流中回收这些元素对实现独立、可持续的未来能源供应至关重要。本文比较了从绿灯荧光体LaPO_4:Ce^(3+),Tb^(3+)回收稀土元素的两种机制:在湿法冶金酸浸工艺前与溶剂冶金机械化学浸出工艺前的机械活化机制。稀土元素浸出率在机械活化后增加60%,完成机械化学浸出工艺后增加98%。高分辨率透射电子显微镜(HR-TEM)成像揭露了系统元素浸出率增加的原因:浸出与浸出模式的改善可归因于晶体形态从单晶体到多晶体的转变。多晶形材料的雏晶尺寸减小至纳米级,使化学单元出现不规则填充,导致晶体内缺陷颗粒边界的增加,从而增强浸出工艺。发明了一种溶剂冶金法将机械活化与浸出工艺结合成一个步骤,这有利于降低运营成本。其结果是简单、高效的工艺提供了更加绿色的荧光体废物回收替代途经。

Metastable phase transitions in Mo-Si and V-Si systems activated by high energy ball milling

Mechanical alloying of Mo Si (Mo 33 Si 67 ) and V Si (V 75 Si 25 ) powder mixtures was activated by high energy ball milling at ambient temperature. The metastable phase transitions in both systems during milling were investigated by X ray diffraction, scanning and transmission electron microscopy. It is found that the alloying processes are closely related to the milling conditions. As far as the Mo Si system is concerned, ball milling leads to the formation of both α MoSi 2 (room temperature phase) and β MoSi 2 (high temperature phase), but lower energy milling favors the formation of β phase, while higher energy milling promotes the formation of α phase. In addition, if the milling energy is high enough, the Mo/Si reaction is governed by a self propagating high temperature process. On the other hand, two different pathways of phase transition in the V Si system were also identified depending on the milling intensity, i.e. weak milling leads to amorphous transition, whereas intensive milling causes the formation of V 3Si and V 5Si 3 intermetallic compounds. Finally, the thermodynamics and kinetics related to the different phase transitions in the two systems were discussed.

Fabrication of Lead Zirconate Titanate Powder Using Ultrasonic Ball Milling Technique

In this research,the ultrasonic ball milling technique has been used to fabricate lead zirconate titanate(PZT)ceramics.PZT with the composition nearly the morphotropic phase boundary(MPB):Pb(Zr_ 0.52Ti_ 0.48)O_3 was studied.The effect of milling time on phase formation of sample powder was examined by X-ray diffraction technique(XRD).Moreover,the physical,dielectric,piezoelectric properties and microstructure of PZT ceramics were investigated.The present results reveal that the ultrasonic ball milling technique results the homogeneous and small size of PZT powder.Furthermore,there is a significantly change occurs in the size of the particles with the short time of milling process.

Fabrication of finegrained Al_2O_3 ceramic at low sintering temperature

A research on fabrication of finegrained Al2O3 ceramic at lower sintering temperature was carried out. Al2O3 powder with 50 nm in diameter is compounded with 11.24%Al and 4.75%Fe（mass fraction） by high-energy ball-milling. Al is got from Al powder which is a component of the materials being milled and Fe from steel milling balls and milling jar during the milling. In this way, nearly no impurity is brought into the composite powder during milling. With hot pressing of the composite powder and pure Al2O3 powder, it is proved that Al2O3 powder can be densified at lower sintering temperature when the powder is compounded in this way. Al2OC and AlFe form during sintering process of the composite powder. With the reactive sintering and multiphase sintering mechanisms, finegrained Al2O3 ceramic is fabricated at low sintering temperature.

高体积分数SiCP／AI金属基复合材料的压渗铸造工艺及热物理性能

本文使用压渗铸造工艺制备含高体积分数SiC颗粒的SiCP／Al复合材料，测试其热导率和热膨胀系数。通过球磨研磨和挤压成型控制SC颗粒大小和无机粘合剂含量，制备出SiC颗粒体积含量为50％～70％的SiC毛坯。优化工艺参数可在SiC毛坯中完全渗透熔融Al液。从体积含量为50％～70％的SCP／Al复合材料的显微组织可知，气孔偏聚于SiC颗粒和Al基体的分界面上，所测的热膨胀系数和热导率与估算值相符合。在SiC颗粒体积分数高于50％～70％时，由于在分界面上存在残余气孔，所测值比估算值小。通过调控工艺参数，高体积分数的SiCP／Al复合材料在先进电子仪器组件上是替代热沉材料的不错选择。