Critical parameters near the ferromagnetic-paramagnetic phase transition in La0.67–xYxBa0.23Ca0.1MnO3 compounds（x=0.10 and x=0.15）

The critical properties of the mixed manganite La0.67–x Y x Ba0.23Ca0.1Mn O3 with x=0.10 and x=0.15 around the paramagnetic(PM)-ferromagnetic(FM) phase transition were investigated through various techniques. These involved modified Arrott plots, Kouvel-Fisher method and Widom scaling relation. Magnetic data, analyzed in the critical region, using the above methods, yielded the critical exponents for(x=0.10) La0.57Y0.10Ba0.23Ca0.1Mn O3(β=0.312±0.002 and γ=1.147±0.003 at T C=299.23±0.05 K). Moreover, the estimated critical exponents of(x=0.15) La0.52Y0.15Ba0.23Ca0.1Mn O3 were β=0.286±0.004 and γ=0.943±0.002 at T C=289.53±0.06 K. The critical exponents’ values were close to the theoretical values of 3D-Ising model and tricritical mean-field model. These results suggested that the present composition should be close to a tricritical point in the La0.67–x Y x Ba0.23Ca0.1Mn O3 phase diagram. Expressing the field dependence as ΔS M∝H n allowed us to establish a relationship between the exponent n and the critical exponents of the material and to propose a phenomenological universal curve for the field dependence of ΔS M.     

3D printed millireactors for process intensification

The scope of the present research aims at demonstrating the 3D printing use in the manufacturing of microchannels for chemical process applications. A comparison among digital model processing applications for 3D print(slicers) and a print layer thickness analysis were performed. The 3D print fidelity was verified in several devices, including the microchannels' printing with and without micromixer zones. In order to highlight the 3D print potential in Chemical Engineering, the biodiesel synthesis was also carried out in a millireactor manufactured by 3D printing. The millireactor operated under laminar flow regime with a total flow rate of 75.25 ml ? min~(-1)(increment of about 130 times over traditional microdevices used for biodiesel production).The printed millireactor provided a maximum yield of Ethyl Esters of 73.51% at 40 °C, ethanol:oil molar ratio of7 and catalyst concentration of 1.25 wt% and residence time about 10 s. As a result of flow rate increment attained in the millireactor, the number of required units for scaling-up the chemical processes is reduced. Using the approach described in the present research, anyone could produce their own millireactor for chemical process in a simple way with the aid of a 3D printer.     

Progressive failure analysis of notched composite plate by utilizing macro mechanics approach

In this study, gradual and sudden reduction methods were combined to simulate a progressive failure in notched composite plates using a macro mechanics approach. Using the presented method, a progressive failure is simulated based on a linear softening law prior to a catastrophic failure, and thereafter, sudden reduction methods are employed for modeling a progressive failure. This combination method significantly reduces the computational cost and is also capable of simultaneously predicting the first and last ply failures (LPFs) in composite plates. The proposed method is intended to predict the first ply failure (FPF), LPF, and dominant failure modes of carbon/epoxy and glass/epoxy notched composite plates. In addition, the effects of mechanical properties and different stacking sequences on the propagation of damage in notched composite plates were studied. The results of the presented method were compared with experimental data previously reported in the literature. By comparing the numerical and experimental data, it is revealed that the proposed method can accurately simulate the failure propagation in notched composite plates at a low computational cost.     

半工业实验规模柱式浮选机的品位分布

本文简要叙述浮选柱半工业实验结果，从品位分布来看，得出矿浆中富集梯度低和精选主要发生在泡沫区两结论。     

Research of modes of electropulse processing for an intensification of processes of deformation of trumpet preparations from titanic alloys

The growing requirements to accuracy of manufacturing of details of flying devices including fromti-tanic alloys,results in substantial growth of labour input of their manufacturing.It speaks that titanic al-loys have rather low module of elasticity,high durability,resilient after removal of loading that results innecessity of performance of honing works after manufacturingfromthemdetails.Nowштамповочноеmanu-facture has progressive the equipment and new ways of punching of details …     

从微晶菱镁矿矿石中选择性浮选菱镁矿

本文指出了从含有高含量杂质(石英、其他硅酸盐以及碳酸钙和白云石)的矿石中选择性浮出微晶菱镁矿的可能性.浮选微晶菱镁矿矿石的特殊问题是从方解石中.尤其是从白云石(Mg(CaCO3)2)中分离菱镁矿(MgCO3),因为这些半溶性盐类矿物的化学、物理化学和晶体化学性质存在相似性.根据在相同pH值下不同的浮选动力学及白云石的选择性絮凝,确立了本文提出的分离菱镁矿和白云石的浮选条件.这些条件已用菱镁矿代表性原矿和试样在实验室浮选试验中得到了验证.因此,确定了通过选择性絮凝白云石的反浮选工艺,此方法在半工业浮选条件下进行了试验,收集了工厂建设中可行性研究所需要的数据.     

欧洲的一个大型铁矿——奥地利施蒂里亚埃尔茨贝格矿

在奥地利南部的施蒂里亚省,奥地利的国营钢铁企业——“奥联钢铁-阿尔平矿业”公司(Voest-Alpine AG),经营着一个欧洲较大的铁矿——施蒂里亚埃尔茨贝格矿steirische Erzberg),该矿名的英文含义是