基于AMESim的液粘调速离合器PID控制特性研究(英文)

为了准确模拟液粘调速离合器电液比例闭环控制特性,使系统能达到稳定转速的目的,基于AMESim仿真软件构建液粘调速离合器PID闭环控制系统仿真模型。采用Ziegler-Nichols整定法确定了PID参数,研究了液粘调速离合器闭环控制系统输出响应特性,分析了PID参数对输出特性的影响。结果表明,该方法能准确地模拟液粘调速离合器PID闭环控制输出响应特性,PID参数对系统输出响应特性和转速稳定性均有较大的影响。通过PID闭环控制系统,液粘调速离合器可以达到恒转速控制,得到的仿真结果为控制器的设计提供了参考依据。     

漆酶在染整加工中的应用

介绍了漆酶的理化性能和催化机理,综合评述了漆酶在纺织纤维改性、漂白、水洗后处理及染色废水脱色中的应用。漆酶应用于染色织物皂洗过程中,不仅能有效降低污水的色度值,进行自清洁处理,减轻印染污水处理的负担,同时又可取代常规的皂洗剂,去除浮色,提高织物的色牢度,有利于纺织品清洁生产和节能减排。     

Effect of various additives to marinating baths on some properties of cattle meat

Longissimus dorsi (LD) muscles obtained from young bull carcasses (Holstein Friesian) were marinated, using solutions containing 0.5% sodium tripolyphosphate (STP), 0.5% dicalciumhydrogen phosphate (CHP) and 0.5% citric acid (CA). All solutions, including a blank, contained 2% NaCl. Expressible moisture, cooking loss, marinade uptake, area gain (increase in slice size), colour coordinate values (L*, a*, b*), marinade and meat pH, and the textural properties of samples were evaluated. Marinating with STP and CHP solutions resulted lower cooking losses. Marinade uptake and area gain were lower for control steaks and steaks marinated with the CA solution. The highest lightness was found in steaks marinated with the CA solution. Steaks marinated with STP and CHP solutions were darker. The CA solution resulted in yellowness of steaks. All treatments significantly affected hardness, chewiness and resilience values of steaks. The lowest hardness value was found in steaks marinated with CA. STP and CHP treatments also improved tenderness.     

A comparison of selected quality features of the tissue and slaughter yield of wild and cultivated pikeperch<Emphasis Type="Italic"> Sander lucioperca</Emphasis> (L.)

The study focused on the comparison of carcass and fillet yields, fillet color, the content of basic components, and the fatty acid composition of tissue from cultivated and wild pikeperch. There was no variation in yield between carcasses and fillets. The brightness and redness of the color of the fillet surfaces of both types of fish were comparable, although the yellowness, chromaticity and shade of color differed. The tissue of cultivated fish had three times more fat (2.87%) than did that of wild fish; the difference was compensated for by water content. The protein and mineral component contents did not vary significantly. The total levels of saturated and monounsaturated acids in the tissue lipids in 1 g of fat varied. No differences were observed between the total amount of polyunsaturated fatty acids (PUFA), PUFAn-3, PUFAn-6, or in the n-3/n-6 proportion. One consequence of the higher fat content in cultivated pikeperch tissue was that the contents of eicosapentaenoic (EPA; 20:5n-3) and docosahexaenoic (DHA; 22:6n-3) acids per 100 g of fillet were significantly higher than in the tissue of wild pikeperch.     

皖南地区荷塘组页岩气成藏条件及有利区预测

通过野外实地观察、样品采集及系列实验分析发现,皖南下扬子区下寒武统荷塘组页岩在研究区内分布广泛,沉积厚度大(约60~360 m),有机质丰度高(达0.5%~7.2%),热演化程度较高(Ro为2.0%~5.5%),达高-过成熟阶段晚期,具有较好的生烃潜力;储集层孔隙度平均为0.716%,为游离气提供了一定的储存空间,等温吸附实验测得吸附气含量平均为0.443 cm3/g,表明研究区页岩具有较强的吸附能力。通过综合研究认为,石台—黟县—泾县—宁国一带为今后的有利勘探区,分布面积约9 100 km2.     

热灌装饮料瓶用丙丁共聚聚丙烯的结构与性能

采用高温凝胶渗透色谱（GPC）仪、差式扫描量热（DSC）仪、偏光显微镜等分析了热灌装饮料瓶用丙丁共聚聚丙烯（牌号PB 13 HF,简称试样1）的结构与性能,并与相应的市售产品（牌号为E 980 BHF,简称试样2）性能进行了对比分析。结果表明:试样1与试样2的相对分子质量及其分布相近;与试样2相比,试样1的熔融结晶性能略有提高,热变形温度、拉伸屈服应力、弯曲应力等刚性较好,冲击强度略低,雾度相近。     

数字信号处理中相位解卷绕问题分析——使用Matlab语言

对Matlab语言中能够保持复向量相位连续性的两个解卷绕命令unwrap和phase的使用方法进行比较,指出它们之间的不同之处。对其源文件进行深入解读,并举例说明同一信号在这两个命令的作用下所得结果不相符的原因。最后通过修改phase命令的M文件或改变unwrap命令的输入参数使二者的输出达到一致,从而扩大了这两个命令的适用范围。     

基于弯曲板波的延迟线振荡器的ANSYS仿真

针对复合板结构中弯曲板波谐振频率计算相对复杂的问题,建立并分析了基于弯曲板波延迟线振荡器的理论模型,计算得到A0(0阶反对称)模式板波的谐振频率为41 MHz;为了验证理论分析的结果,利用有限元软件ANSYS建立了基于弯曲板波的延迟线振荡器的3D有限元模型,并对其进行了谐响应分析以及瞬态动力学分析。谐响应分析得到A0模式的谐振频率为37.2 MHz,与理论计算结果的相对误差为9.3%;瞬态动力学分析得到A0模式的谐振频率为39.1 MHz,与理论计算结果的相对误差为4.6%。计算和仿真为基于弯曲板波的延迟线振荡器的结构设计提供了重要的依据。     

石墨烯的SiC外延生长及应用(续)

正3.3 X射线光电子能谱XPS能谱分析的基本原理:一定能量的X光照射到样品表面和待测物质发生作用,可以使待测物质原子中的电子脱离原子成为自由电子。通过接收并测量这些光电子的能量,得到原子或分子内部各轨道的结合能,从而就可以了解样品中元素的组成。图8所示为样品的XPS能谱图,图中各峰值