Experimental study of the relationship between separation performance and lengths of vortex finder of a novel de-foulant hydrocyclone with continuous underflow and reflux function

To solve the blockage and defer the fouling of sewage heat exchanger, a novel de-foulant hydrocyclone with continuous underflow and reflux function was proposed. Experimental results demonstrated that the novel hydrocyclone had a remarkable behavior on separating the sand (75–250 μm) and foulant (<4 mm). The continuous underflow and reflux function could significantly improve the separation efficiency by relieving the particle re-entrainment and eliminating the air core without increasing energy consumption (<17 kPa) and split ratio (<10%) considerably. Besides, the range of optimum vortex finder length was proportional to the particle density.     

40%唑醚·啶酰菌水分散粒剂配方及工艺研究

通过对润湿剂、分散剂、填料等进行筛选,确定40%唑醚·啶酰菌水分散粒剂配方。分散剂采用Mortwet D425(4%)、AJ-002(2%)、REAX910(2%)与聚羧酸盐分散剂SP-2836(2%)或Geropon T36(2%)复配,以K12为润湿剂,玉米淀粉为填料。所制水分散粒剂有较高的悬浮率,较好的热稳定性。生产中水分散粒剂烘干优选流化床沸腾烘干方式,不同的捏合设备以及捏合时间对产品性能有影响,但粉碎方式对产品影响不大。     

Synthesis of osmium borides by mechanochemical method

Transition metal osmium borides were synthesized by mechanochemical method using high‐energy ball‐milling with Os (Osmium) and B (Boron) powders as raw materials. The formation process, reaction mechanism, and thermal stability of the mechochemically synthesized osmium borides were studied. Almost pure Os₂B₃ phase was obtained when the Os‐to‐B molar ratio was 1:2; while ReB₂‐type hexagonal OsB₂ with a small amount of RuB₂‐type orthorhombic OsB₂ was obtained when the Os‐to‐B molar ratio was 1:3. Stoichiometry OsB₂ was obtained from boron rich starting mixture powders due to the B loss during the high‐energy ball‐milling process. It was also found that WC and osmium oxide were present as contaminants after ball milling for 40 hours. Heat treatment results revealed that the as‐synthesized Os₂B₃ powders are thermally stable in flowing Ar up to 800°C, but a transformation from hexagonal to orthorhombic structure partially occurred for the OsB₂ powders as low as 600°C.     

Spatial ions distribution of the bonding interface in YAG/Nd:LuAG composite laser ceramic

Composite YAG/Nd:LuAG transparent ceramics were fabricated by a thermal bonding process. The spatial distribution of ions around the original bonding interface of the YAG/Nd:LuAG composite laser ceramic was investigated. Around the original bonding interface, Lu³⁺ and Y³⁺ ions were replaced with each other in dodecahedral symmetry sites. Results from X‐ray photoelectron spectroscopy (XPS) and energy dispersive spectroscopy (EDS) quantitative chemical analyses positively show that the distance of Y³⁺ ions diffused in the LuAG part is about 35 μm, while Lu³⁺ ions’ diffused distance in the YAG part is about 5 μm. This corresponds to the diffusion coefficient of Y³⁺ ions and Lu³⁺ ions (D_Y=2.43 ×10^?10 cm²/s and D_Lu=0.56×10^?10 cm²/s at 1750°C). The formation of Y_xLu_(3?x)Al₅O₁₂ polycrystal in the bonding section explains the complete combination of LuAG and YAG without a bonding interface. Moreover, no diffusion phenomenon of Nd³⁺ ions was detected near the original bonding interface.     

LaCoO_3钙钛矿型催化剂非均相Fenton处理兰炭废水

以苯甲醇为溶剂,采用水热法制备LaCoO_3钙钛矿型催化剂,研究LaCoO_3钙钛矿型催化剂非均相Fenton处理兰炭废水的最佳工艺条件及催化机理。结果表明,在过氧化氢用量3 m L、LaCoO_3钙钛矿型催化剂用量0.2 g、pH=4和反应温度25℃条件下,LaCoO_3钙钛矿型催化剂非均相Fenton处理兰炭废水的COD去除率达到72.7%,通过自由基捕获剂叔丁醇的加入及一级动力学模型研究非均相Fenton过程机理。     

基于微分代数积分矩量法的聚并器超细颗粒聚团研究

研究聚并器内布朗聚团和湍流聚团引起超细颗粒聚团,特别考虑颗粒之间近程力（范德华引力、静电斥力）和颗粒与气体之间的流体力学作用力对颗粒聚团的影响。基于FLUENT软件UDF功能自定义聚团核,考虑颗粒之间近程力和流体力学作用力对聚并率的影响,引入碰撞效率α对聚团核进行修正,得到修正湍流聚并模型并将该模型与理想湍流聚并模型进行比较。应用群体平衡模型（population balance model,PBM）耦合CFD对颗粒聚团过程进行数值模拟,并采用微分代数积分矩量法（DAE-QMOM）求解群体平衡方程。结果表明：理想湍流聚并模型与实验结果误差为8.92%,而修正改进的湍流聚团模型与实验结果误差仅为3.35%,更加符合实际情况;微分代数积分矩量法具有较高的效率,而且误差较小,相比PD积分矩量法有明显的优势,稳定性也比较突出。     

Li3AlN2—a self‐activated yellow light emitting wide‐bandgap semiconductor used for LEDs

In allusion to the problems existing in the defect‐related luminescent materials, a series self‐activated light emitting semiconductors of Li₃AlN₂: R (R=0, Na⁺, Mg²⁺, Si⁴⁺, Tb³⁺, Eu³⁺) have been successfully synthesized by sample‐pressure sintering. Under the excitation at 422 nm, a yellow light peaked at 580 nm have been observed in the host lattice of Li₃AlN₂. The crystal structure and the electron structure of Li₃AlN₂ have been measured to investigate the defect‐related luminescent properties of Li₃AlN₂ using the Rietveld refinement on the basic of X‐ray diffraction data and the density functional theory (DET). The results show that Li₃AlN₂ crystallizes in cubic phase with full filled edge‐shared (Al/Li)N₄ tetrahedrons and is a wide‐bandgap semiconductor. The impurity defects produced by ions substitution have also been investigated, which leads to the red‐shift of the emission peak. Finally, the photoluminescence excitation (PLE) spectrum of Li₃AlN₂ with two excitation bands peaked at 300 nm and 422 nm has been detected, and the latter matches well with near‐UV LED chips. The thermal stability shows that integral intensity of Li₃AlN₂ at 150°C still has 60% of the initial intensity at room temperature. The results indicate their potential applications as the LED used phosphors.     

渗透汽化-结晶耦合分离稀溶液中的香兰素

以聚醚嵌段共聚酰胺（PEBA2533）为膜材料,采用干法相转化法制备性能优异的高分子膜,用于渗透汽化-结晶耦合（PVCC）分离系统中回收稀水溶液中的香兰素。采用扫描电子显微镜（SEM）对PEBA2533膜的形貌进行表征。考察原料液浓度、温度对膜渗透汽化性能的影响。结果表明：随着溶液浓度的增加,PEBA2533膜溶胀性能增加,说明PEBA2533能够优先吸附香兰素;随原料液浓度增加,香兰素渗透通量增加,分离因子略微下降;原料液温度增加,香兰素渗透通量和分离因子都增加;并通过Arrhenius方程计算得到香兰素比水对温度更加敏感。PVCC系统中控制一级冷凝器温度为2℃时,一级冷凝器中结晶态香兰素通量为39.52 g·m^-2·h^-1,纯度在99%以上。     

Dietary patterns are associated with type 2 diabetes mellitus among middle-aged adults in Zhejiang Province,China

Background

Although some studies have shown the associations between dietary patterns and the risk T2DM in a general population, the associations in middle-aged Chinese have been rarely studied to date. In this study, we aimed to characterize dietary patterns in Chinese adults aged 45-59y (n?=?1918) and to evaluate the relationship between dietary patterns and the risk of T2DM.

Methods

The study population was a part of the population-based the Nutrition and Health Study conducted in the city of Hangzhou, Zhejiang Province, China. Dietary intake was assessed by using a validated food frequency questionnaire (FFQ). Multivariate logistic regression analyses were used to estimate the associations between dietary patterns and the risk of T2DM, adjusting for potential confounders.

Results

Three major dietary patterns were identified using factor analysis, including the traditional southern Chinese, the Western, and the grains-vegetables patterns. After adjusting for the potential confounders, subjects in the highest quartile of the Western dietary pattern scores had greater odds ratio(OR) for T2DM(OR?=?1.28; 95% confidence interval (CI): 1.103–1.697; P?=?0.02) than did those in the lowest quartile. Compared with those in the lowest quartile, subjects in the highest quartile of the grains-vegetables dietary pattern scores had a lower OR for T2DM (OR?=?0.72; 95% CI:0.596–0.952; P?=?0.04). Moreover, no significant association was found between the traditional southern Chinese dietary pattern and risk of developing T2DM.

Conclusions

Our findings indicated that the Western dietary pattern was associated with an elevated risk, whereas the grains-vegetables dietary pattern was associated with a reduced risk of T2DM. Further researches are needed to confirm these findings.

     

腰果酚表面活性剂的合成研究进展

综述了腰果酚表面活性剂的合成研究进展,重点介绍了腰果酚磺酸盐、腰果酚硫酸盐、腰果酚羧酸盐及腰果酚聚氧乙烯醚等表面活性剂的合成方法,并分别对其性能进行了概述。腰果酚表面活性剂除了具有优良的性能,其绿色的原料来源也更符合发展潮流。