Yttria-reinforced copper matrix composites were prepared by dry ball milling （DBM） and wet ball milling （WBM）, respectively, followed by spark plasma sintering （SPS）. It is to determine which milling process is ...Yttria-reinforced copper matrix composites were prepared by dry ball milling （DBM） and wet ball milling （WBM）, respectively, followed by spark plasma sintering （SPS）. It is to determine which milling process is better for fabricating Cu-Y2O3 composites. It is found that Cu-Y2O3 composites synthesized by DBM exhibit better densification, mechanical and electrical properties than those by WBM. Less agglomeration of reinforcements in the bulk composites by DBM is responsible for the better perfor- mances. To further understand the reason of less agglomeration of Y2O3 in the bulks by DBM, morphologies of prepared powders were investigated and analyzed. Higher ball＇s impact energy and the formation of copper oxide on the matrix surface during DBM process contribute to small matrix particles, which is beneficial for less agglomeration.展开更多
A new self-made additive of amidocyanogen-acetic salt was used in wet ball-grind technique （WBGT） for preparing hydrogen storage alloys, and the effect on the electrochemical performance of the alloy electrode was i...A new self-made additive of amidocyanogen-acetic salt was used in wet ball-grind technique （WBGT） for preparing hydrogen storage alloys, and the effect on the electrochemical performance of the alloy electrode was investigated in detail. It was found that the prepared electrode had perfect electrochemical performances, such as rapid activation, high capability, high-rate discharge （HRD） ability, and good stability. The first discharge capacitance at 0.2 C （throughout this study, n C rate means that the rated capacity of a hydrogen storage alloy （full capacity） is charged or discharged completely in 1/n h） reached 278 mAh·g^-1 and the discharge capacitance reached the maximum of 322 mAh·g^-1 only after two charge-discharge cycles. For the dry method, wet method, and WBGT, the high rate discharge （HRD） values （C5 c/C0.2c ratio） were approximately 0.59, 0.76, and 0.83, respectively. The stable discharge capacity at 3 C increased from 275 mAh·g^-1 （dry method）to 295 mAh·g^-1 （WBGT）.展开更多
Fe3O4 nanoparticles with sizes ranging from 30 to 80 nm were synthesized by wet milling iron powders in a planetary ball mill. The phase composition and the morphologies of the as-synthesized products were measured by...Fe3O4 nanoparticles with sizes ranging from 30 to 80 nm were synthesized by wet milling iron powders in a planetary ball mill. The phase composition and the morphologies of the as-synthesized products were measured by X-ray diffraction （XRD）, scanning electron microscopy （SEM） and transmission electron microscopy （TEM）. Nanosized Fe3O4 particles were prepared by wet milling metallic iron powder （-200 mesh, 99%） in a planetary ball mill equipped with stainless steel vials using iron balls under distilled water with a ball-to-powder mass ratio of 50：1 and at a rotation speed of 300 rpm. The use of the iron balls in this method played a key role in Fe3O4 formation. The present technique is simple and the process is easy to carry out.展开更多
The ball milling process and the CuWO-WOprecursors were investigated, and a new highly concentrated wet ball-milled process(HWM) was designed. W-20 wt% Cu composite powders with excellent sintering property were synth...The ball milling process and the CuWO-WOprecursors were investigated, and a new highly concentrated wet ball-milled process(HWM) was designed. W-20 wt% Cu composite powders with excellent sintering property were synthesized by highly concentrated wet ballmilled process and co-reduction. The powders were characterized by scanning electron microscopy(SEM), X-ray diffraction(XRD), field electron transmission electron microscopy(FESEM) and laser-diffraction diameter tester.The results indicate that particle size of W03-CuO powder mixtures decreases to 390 nm rapidly with the milling time increasing to 5 h. The CuWOprecursors promote the microstructural homogeneity of W and Cu. W-Cu composite powders have a highly dispersed and well sintering property. The particle size of W-Cu powders milled by HWM for 5 h is about 680 nm. High-resolution transmission electron microscopy(HRTEM) result suggests that W phase and Cu phase are mixed at nanometer scale. The above W-Cu composite powders reach the relative density of about 99.3%.展开更多
针对多工况条件下球磨机关键负荷参数测量面临的复杂性问题,提出基于流形正则化域适应(domain adaptation with manifold regularization,DAMR)湿式球磨机负荷参数软测量的方法。该方法首先采用集成流形约束、最大方差及最大均值差异寻...针对多工况条件下球磨机关键负荷参数测量面临的复杂性问题,提出基于流形正则化域适应(domain adaptation with manifold regularization,DAMR)湿式球磨机负荷参数软测量的方法。该方法首先采用集成流形约束、最大方差及最大均值差异寻找特征变换矩阵,然后,将源建模领域和未建模领域的特征信息投射到公共子空间,最后,在子空间建立模型得到球磨机关键负荷参数的预测值。实验结果表明该方法能以较高的精度实现未知工况下湿式球磨机关键负荷参数的预测,且该方法对于流程工业多工况软测量和过程监控研究有一定的参考价值。展开更多
基金financially supported by the National Key Research and Development Program of China (No. 2016YFB0301400)the Organization Department of Jiangxi Province(No. 2012215)+1 种基金the Education Department of Jiangxi Province (No. KJLD13041)the Outstanding Doctoral Dissertation Project Fund of JXUST (No. YB2017011)
文摘Yttria-reinforced copper matrix composites were prepared by dry ball milling （DBM） and wet ball milling （WBM）, respectively, followed by spark plasma sintering （SPS）. It is to determine which milling process is better for fabricating Cu-Y2O3 composites. It is found that Cu-Y2O3 composites synthesized by DBM exhibit better densification, mechanical and electrical properties than those by WBM. Less agglomeration of reinforcements in the bulk composites by DBM is responsible for the better perfor- mances. To further understand the reason of less agglomeration of Y2O3 in the bulks by DBM, morphologies of prepared powders were investigated and analyzed. Higher ball＇s impact energy and the formation of copper oxide on the matrix surface during DBM process contribute to small matrix particles, which is beneficial for less agglomeration.
文摘A new self-made additive of amidocyanogen-acetic salt was used in wet ball-grind technique （WBGT） for preparing hydrogen storage alloys, and the effect on the electrochemical performance of the alloy electrode was investigated in detail. It was found that the prepared electrode had perfect electrochemical performances, such as rapid activation, high capability, high-rate discharge （HRD） ability, and good stability. The first discharge capacitance at 0.2 C （throughout this study, n C rate means that the rated capacity of a hydrogen storage alloy （full capacity） is charged or discharged completely in 1/n h） reached 278 mAh·g^-1 and the discharge capacitance reached the maximum of 322 mAh·g^-1 only after two charge-discharge cycles. For the dry method, wet method, and WBGT, the high rate discharge （HRD） values （C5 c/C0.2c ratio） were approximately 0.59, 0.76, and 0.83, respectively. The stable discharge capacity at 3 C increased from 275 mAh·g^-1 （dry method）to 295 mAh·g^-1 （WBGT）.
文摘Fe3O4 nanoparticles with sizes ranging from 30 to 80 nm were synthesized by wet milling iron powders in a planetary ball mill. The phase composition and the morphologies of the as-synthesized products were measured by X-ray diffraction （XRD）, scanning electron microscopy （SEM） and transmission electron microscopy （TEM）. Nanosized Fe3O4 particles were prepared by wet milling metallic iron powder （-200 mesh, 99%） in a planetary ball mill equipped with stainless steel vials using iron balls under distilled water with a ball-to-powder mass ratio of 50：1 and at a rotation speed of 300 rpm. The use of the iron balls in this method played a key role in Fe3O4 formation. The present technique is simple and the process is easy to carry out.
基金financially supported by the National Natural Science Foundation of China (No. 51274246)
文摘The ball milling process and the CuWO-WOprecursors were investigated, and a new highly concentrated wet ball-milled process(HWM) was designed. W-20 wt% Cu composite powders with excellent sintering property were synthesized by highly concentrated wet ballmilled process and co-reduction. The powders were characterized by scanning electron microscopy(SEM), X-ray diffraction(XRD), field electron transmission electron microscopy(FESEM) and laser-diffraction diameter tester.The results indicate that particle size of W03-CuO powder mixtures decreases to 390 nm rapidly with the milling time increasing to 5 h. The CuWOprecursors promote the microstructural homogeneity of W and Cu. W-Cu composite powders have a highly dispersed and well sintering property. The particle size of W-Cu powders milled by HWM for 5 h is about 680 nm. High-resolution transmission electron microscopy(HRTEM) result suggests that W phase and Cu phase are mixed at nanometer scale. The above W-Cu composite powders reach the relative density of about 99.3%.
文摘针对多工况条件下球磨机关键负荷参数测量面临的复杂性问题,提出基于流形正则化域适应(domain adaptation with manifold regularization,DAMR)湿式球磨机负荷参数软测量的方法。该方法首先采用集成流形约束、最大方差及最大均值差异寻找特征变换矩阵,然后,将源建模领域和未建模领域的特征信息投射到公共子空间,最后,在子空间建立模型得到球磨机关键负荷参数的预测值。实验结果表明该方法能以较高的精度实现未知工况下湿式球磨机关键负荷参数的预测,且该方法对于流程工业多工况软测量和过程监控研究有一定的参考价值。
