基于PLC和触摸屏的车身总装夹具控制系统设计

车身总装工艺是白车身生产的关键工艺,论文用程序自动控制代替手动气压控制,确保达到车身总装质量和生产效率的要求.该设备的控制系统是以PLC控制技术为核心,以触摸屏为人机操作界面,采用二者配合控制实现了车身总装夹具的控制要求.设备已经投入生产,运行结果表明:该系统在降低了设备成本的同时,有效的缩短了生产周期,对其它类产品设计有一定参考价值.     

元青花《昭君出塞》罐艺术特征与主题思想研究

昭君出塞故事源于汉代,绵延流传,元青花《昭君出塞》罐表现的即为昭君出塞故事题材。元青花《昭君出塞》罐具有鲜明的艺术特征,同时,亦具有丰富而深邃的主题思想内涵。     

白萝卜多酚氧化酶的酶学特性研究

白萝卜作为我国第二大蔬菜。其贮运和加工过程中的褐变多以酶促褐变为主,全面系统地了解白萝卜多酚氧化酶（PPO）的酶学特性,并研究其抑制手段,对提升白萝卜及其制品的品质和商品价值有着重要的意义。本文以新鲜白萝卜为原材料,采用丙酮洗涤、0.2 mol/L磷酸盐缓冲溶液匀浆法从中提取PPO,考察了pH、温度对酶活的影响,分析了其温度稳定性、底物浓度对PPO活性的影响,探讨了过程的反应动力学,并对多种酶抑制剂对PPO活性的影响进行了比较,为控制加工过程中白萝卜的酶促褐变提供了理论依据。试验结果表明：以邻苯二酚为底物,该酶的最适pH 值为6.0,最适反应温度为40 ℃,Km和Vmax值分别为53.8 mmol/L和588 U/min。90 ℃热处理2.5 min或85 ℃热处理3.5 min可基本完全钝化其活性,Vc、异Vc和L-cys对PPO酶活的抑制较为明显。     

低醇半干白葡萄酒的酵母菌耐受性研究

为了考察低醇半干白葡萄酒的酵母菌稳定性,进行山梨酸钾和游离二氧化硫不同浓度的梯度实验,以确定该产品酵母菌的安全耐受浓度.实验结果表明低醇半干白葡萄酒的山梨酸钾的适宜添加浓度为150mg/L,游离二氧化硫浓度为30mg/L～35mg/L,在此基础上酵母菌的安全耐受浓度为酵母菌数＜50个/100mL酒样.     

高帧频大面阵彩色CMOS相机Bayer滤波器解码算法

在图像处理领域中,利用高帧频大面阵数字相机不仅可以提高图像采集精度,而且也可以捕捉到目标的一些细节动作,更好地测量出目标的运动轨迹与姿态。介绍了高帧频大面阵彩色CMOS相机的Bayer滤波器解码算法,实现了彩色图像输出。这样就能够更好地对一些具有颜色特征的目标进行提取与识别,简化算法,缩短运算时间。     

A potential red-emitting phosphors scheelite-like triple molybdates LiKGd_2(MoO_4)_4:Eu~(3+) for white light emitting diode applications

A series of novel red-emitting phosphors scheelite-like triple molybdates LiKGd2-xEux(MoO4)4(0.1 ≤ x ≤ 1.9) were synthesized by solid state reaction method and their photoluminescence properties were investigated. The photoluminescence results show that all samples can be excited efficiently by UV (396 nm) light and blue (466 nm) light and emit red (615 nm) light with line spectra,which are coupled well with the characteristic emission from UV-LED and blue LED,respectively. The experimental results and thei...     

陇西腊肉复合保鲜剂配方优化

以陇西蕨麻猪肉为原料制备陇西腊肉,3℃条件下贮藏90d,以腊肉的感官评分、挥发性盐基氮含量和菌落总数为检测指标进行综合评价,通过单因素试验和响应面优化试验探究大蒜素、茶多酚、生姜提取物等天然保鲜剂对腊肉品质的影响.结果表明:单一保鲜剂的最适剂量为大蒜素质量浓度1.0g/100mL、茶多酚质量浓度3.0g/100mL、生...     

Effect of Boron and Heat Treatment on Mechanical Properties of White Cast Iron for Mining Application

 Heat treatment methods were applied to white cast iron for improving the impact and wear resistance. Additionally, chemical composition optimization was made. Furthermore, the effect of boron addition on such applications was investigated. Samples were investigated by using optical and electron microscope methods. Hardness, wear and impact tests were conducted. The results showed that the secondary carbides in the standard alloy were iron-enriched, needle-like carbides M3C when the boron-added alloy contained Fe23(C,B)6 type, globular secondary carbides. It was concluded that heat treatment B provided higher wear and hardness properties, compared to the standard heat treatment. Optimum mechanical properties were obtained by lower destabilisation temperatures and increasing temperature reduced the wear resistance and hardness.     

一种小型LED照明工具的设计方法研究

发光二极管同诸如白炽灯、荧光灯和气体放电灯等传统的光源比较,有着显著的优势,将成为新一代的照明光源。为了使其在照明领域的应用越来越广泛,对LED照明设计的方法做了初步研究,给出了LED光源的计算方法和相应的光学器件的设计原理。用一种小型LED照明工具的设计实例来证明了此设计方法的可行和便捷。