Analysis of chemical compounds and toxicological evaluation of Forsythia suspensa leaves tea

To determine the compositions of Forsythia suspensa leaves tea (FSLT) and its safety, the chemical compounds were analysed with some methods, and the toxicity was evaluated in Kunming mice and Wistar rats. The results showed that FSLT contained rich flavonoid, lignans, triperpene acids, amino acids, and mineral elements. In the acute toxicity study, none of the mice died, and no obvious poisoning symptoms were observed after 14 days in mice at the dose of 15 mg/g·body weight (bw) FSLT; in the sub-chronic toxicity, no abnormal or dead rat was found at the dose of 1, 3, and 10 mg/g·bw during 90 days feeding administration; there was no significant difference in bw and food consumption; no significant differences were found in each hematology and serum biochemistry parameter and organ/body weight ratio comparing with the control experimental group. The results revealed that the FSLT has low or no toxicity via oral administration. Therefore, FSLT is very suitable and safe to be used as a new resource food.     

The production of volatile compounds in model casein systems with varying fat levels as affected by low-frequency ultrasound

The effects of low-frequency ultrasound on the production of volatile compounds in model casein protein systems containing various fat concentrations of 2%, 4% and 6% (w/w) were investigated. Ultrasound application was performed at 20 kHz for up to 10 min which corresponded to energy densities ranging from 9.54 to 190.8 J mL⁻¹. Similar volatile compounds were detected both in pure fat and mixtures of casein and fat (CF) systems. These volatiles belonged to the groups of aldehydes, ketones, esters, alcohols and hydrocarbons, which were the products of oxidation of lipids or protein degradation due to acoustic cavitation. The amount of fat in the casein systems had minor effects on the production of volatiles, whereas the production of volatile compounds was significantly affected by the ultrasound treatment. Short sonication times <5 min generated similar volatile profiles to the untreated samples. In contrast, prolonged sonication for 5 and 10 min considerably increased the production of volatile compounds and the amounts of fatty acids. Thus, the application of low–frequency ultrasound for short periods should be considered to minimise the production of volatile compounds which can ultimately affect the taste.     

Auto-thermal reforming of acetic acid for hydrogen production by ZnxNiyCrOm±δ catalysts: Effect of Cr promoted Ni-Zn intermetallic compound

A series of Zn_xNi_yCrO_m±δ catalysts were synthesized via a typical co-precipitation method, in which Zn-Cr layered double hydroxides (LDHs) were found and Ni-Zn intermetallic compound (IMC) was formed after reduction in hydrogen. During auto-thermal reforming (ATR) of acetic acid (HAc), the Ni-Zn IMC was transformed into Ni/(amorphous-ZnO)-ZnCr₂O₄ species with uniformed distribution and appropriate interaction within these Ni-Zn-Cr-O species; besides, the adsorbed oxygen promoted the activation and transfer of oxygen species; therefore, deactivation by oxidation, sintering and coking was inhibited. And the optimized Zn_2.37Ni_0.63CrO_4.5±δ catalyst presented high activity and stability in a 45-h ATR test with HAc conversion near 100% and hydrogen yield at 2.7 mol-H₂/mol-HAc, showing potential for hydrogen production via ATR of HAc.     

异步电机的模糊控制研究

阐述了模糊控制器用于交流电动机调速的控制方法,重点讨论了简单模糊控制、复合模糊控制等几种典型的模糊控制方法和技术,分析了各自的特点和存在的问题,并给出了模糊控制的实现方法和手段,说明了模糊控制适应非线性时变、滞后系统控制的特点。     

膨润土复合絮凝剂制备及造纸黑液治理

针对碱法麦草浆造纸黑液的特殊性质，介绍一种用钙基膨润土制备高效复合絮凝剂的方法．经试验研究．优选出了制备时的最佳工艺条件；产品经应用于此类黑液的处理絮凝．取得了较好的效果。     

高碱灰渣烧结熔融过程中的物相变化

为了掌握高碱灰渣烧结熔融过程中的物相变化规律，选取黑液煤浆灰渣展开研究.试验中采用经低温灰化后，粒径为38.5~74.0 μm的灰样，在不同温度下测出烧结率.然后对烧结灰进行XRD物相分析和SEM微区结构分析.结果表明：高碱灰渣具有很强的烧结熔融特性，这主要是因为大量较低熔点的黝方石、蓝方石、霞石、无水芒硝等物相生成.高碱灰渣钠基化合物的物相变化过程为黝方石（Na₈Al₆Si₆O₂₄SO₄）、无水芒硝（Na₂SO₄)黝方石、霞石（Na₆KAl₇Si₉O₃₂)蓝方石（K_1.6Ca_2.4Na_4.32(Al₆Si₆O₂₄)(SO₄)_1.52）、霞石（NaAlSiO₄）.     

基于滑模变结构控制的电机-泵组、阀复合调速的研究

采用电机-泵组、阀并联复合控制较好地解决了液压马达调速过程中快速性与效率之间的矛盾，在控制策略上提出用滑模变结构控制（SMVSC）来提高对不确定干扰的鲁棒性，建立了试验平台.分析了阀控/泵控性能差异的本质原因，探讨了电机-泵组子系统中存在的相乘非线性，介绍了电机-泵组、阀并联复合控制的原理.应用滑模变结构原理设计了滑模变结构控制器，对于SMVSC带来的抖动提出了抑制措施.通过仿真结果可以看出，基于SMVSC的电机-泵组、阀并联复合调速系统动态响应明显加快，系统对马达负载扰动的鲁棒性增强.     

消失模铸造工艺中涂料的选择与配制

通过对消失模铸造工艺中涂料的选择分析 ,找到了消失模工艺中涂料的最佳选择方法     

磨矿介质对钼精矿碳含量影响研究

分析研究了低铬合金铸球和复相球墨铸球中碳的赋存状态及其对普通钼精矿、57钼精矿和二硫化钼粉碳含量的影响,指出用浮选法生产低碳57钼精矿,一段磨矿介质不宜使用复相球墨铸球.     

几种不同碳化物颗粒在堆焊复合材料中的特征

用硬度、金相、Ｘ射线衍射、磨损试验等测试方法，对几种不同类型的管装碳化物硬质合金堆焊焊条进行了性能的对比试验，探讨了烧结ＷＣ、铸造ＷＣ和烧结ＴｉＣ堆焊合金的不同特性：铸造ＷＣ耐磨性最高，但冲击韧性差；烧结ＴｉＣ和烧结ＷＣ耐磨性相当，但ＴｉＣ焊接工艺较差，为应用不同类型的管装碳化物耐磨焊条提供一定的参考数据