Crude Wax Extracted from Rice Bran Oil Improves Oleogel Properties and Oxidative Stability

Crude wax extracted from rice bran oil (RBO) is used to improve the oleogel properties and oxidative stability of RBO. The effect of crude rice bran wax (CrBW) on the formation characteristics and oxidative stability of oleogels is discussed. The results show that oleogels can be formed with 7.0 wt% CrBW at 20 °C. As the concentration of CrBW increases from 7.0 to 11.0 wt%, the hardness and solid fat content (SFC) of the oleogels increase significantly, and the oleogels are primarily β' crystals. Moreover, oleogel crystals formed with 5 and 7 wt% CrBW are flocculent; when the amount included is 9%, the oleogel crystals are transformed into long dendrites, and the density rises. After 90 days of storage at 20 °C, the peroxide value of oleogels formed with 9.0 wt% CrBW slowly rises from 3.21 to 6.52 mmol kg⁻¹. Practical Applications: Oleogels prepared here by CrBW and RBO are an innovative structural lipid without trans fats. Useful information on the rich fats and nutrients in CrBW is provided, which reduces the production cost and improves the industrial production capacity.     

Improvement of coercivity and thermal stability of Nd-Fe-B sintered magnets by intergranular addition of Tb80Fe20 alloy

To improve the coercivity and temperature stability of Nd-Fe-B sintered magnets for high-temperature applications, the eutectic Tb₈₀Fe₂₀ (wt%) alloy powders were added into the Nd-Fe-B sintered magnets by intergranular method to enhance the coercivity (H_cj) and thermal stability. The microstructure, magnetic properties and thermal stability of the Nd-Fe-B magnets with different Tb₈₀Fe₂₀ contents were studied. The experimental results demonstrate that the coercivity (H_cj) of the sintered Nd-Fe-B magnet is significantly enhanced from 14.12 to 27.78 kOe, and the remanence (B_r) decreases not obviously by introducing 4 wt% Tb₈₀Fe₂₀ alloy. Meanwhile, the reversible temperature coefficients of coercivity (β) and remanence (α) of the Nd-Fe-B magnets are increased from ?0.5634%/℃ to ?0.4506%/℃ and ?0.1276%/℃ to ?0.1199%/℃ at 20–170 ℃, respectively. The Curie temperature (T_C) of the Nd-Fe-B magnet is slightly enhanced with the increase of Tb₈₀Fe₂₀ content. Moreover, the irreversible flux magnetic loss (h_irr) is obviously reduced as Tb₈₀Fe₂₀ addition increases. Further analysis of the microstructure reveals that a modified microstructure, i.e. clear and continuous RE-rich grain boundary layer, is acquired in the sintered magnets by introducing Tb₈₀Fe₂₀ alloy. The associated mechanisms on improved coercivity and thermal stability were comprehensively researched.     

机械合金化Al—12Ti—6Nb合金的热稳定性

将机械合金化（ＭＡ）Ａｌ－１２Ｔｉ－６Ｎｂ合金在５５０℃下空气中长时间暴露后，用光学显微镜和电子探针对其组织结构变化进行了观察与分析，测定了维氏硬度。结果表明，ＭＡＡｌ－１２Ｔｉ－６Ｎｂ表现出良好的热稳定性，在５５０℃下暴露２００ｈ后，Ａｌ３Ｔｉ中的亚稳的α－Ｔｉ核才全部转变为Ａｌ３Ｔｉ，Ａｌ３Ｔｉ颗粒随之粗化，饼状的Ａｌ３Ｔｉ变成椭球体；Ａｌ３Ｔｉ颗粒的粗化是通过Ｔｉ，Ａｌ原子扩散所控制的α－Ｔ     

Preparation and characterization of high salts polymer electrolyte based on poly（lithium acrylate）

1　INTRODUCTIONWorldwide research and efforts are currentlyunderway to fabricate all solid state, rechargeableLi and Li ion batteries utilizing Li+ conductivepolymer electrolytes[1]. Solid polymer electrolytespossesses many advantages including high ionicconductivity, high specific surface energy, solventfree, wide electrochemical stability windows, lightand easy processability[2]. Apart from polyethy lene oxide ( PEO )[3], poly ( vinyl alcohol )(PAV)[4], …     

影响中小企业球铁质量稳定的因素

分析了影响中小企业球铁生产稳定性的关键因素,指出在一定的原材料条件下,目前中小型企业生产球铁存在的问题是温度偏低,孕育方法不当。     

TEMPERED BAINITE EMBRITTLEMENT IN SOME STRUCTURAL STEELS

The variations of microstructures and mechanical properties of steels 15CrMnMoV,18Mn2CrMoB,18Cr2Ni4W,30CrMnSi,30CrMnSiNi2 and 40CrMnSiMoV,which weretempered at different temperatures after austempering and continuous cooling at given rates,have been investigated.Based on the experimental results,the behaviour and mechanism oftempered bainite embrittlement(TBE)have been discussed.Finally,the theoretical and prac-tical basis for selecting the optimum tempering temperature of steels with bainite structure af-ter heat treatment are proposed.     

填隙Ti2Ni相形成条件的模式识别分析

在多维键参数空间中对填隙Ti_2Ni相化合物的形成条件做模式识别分析,由于前过渡金属原子组成的八面体空穴中填入C,N.O原子使Ti_2Ni结构稳定化,此结构的分布区扩大,邻近的Al_2Cu,MoSi_2结构分布区减小。     

非稳态轧制时轧机振动稳定性的数值分析

利用轧制理论方程和机械振动理论的能量判据 ,给出了一个较精确的分析轧机传动系统扭转振动稳定性的数值计算方法