废旧利乐包 / 木屑复合板热压优化工艺研究

为提高废旧利乐包的再利用效率,扩大其在包装领域的应用范围,研究了废旧利乐包/木屑复合板制备的热压优化工艺。采用正交试验法,以施胶量、热压温度、热压时间、利乐包与木屑质量比为影响因素,分别以静曲强度、弹性模量和2 h吸水厚度膨胀率为检测指标,得到了此种复合板热压优化工艺参数。结果表明板材热压优化工艺参数为:施胶量14%,热压温度150℃,热压时间420 s,利乐包与木屑质比比4∶6,在此条件下,板材最大静曲强度为23.1 MPa,最大弹性模量为2917 MPa,2 h吸水厚度膨胀率最小,为6.1%。     

Role of Combined Na2HPO4 and ZnCl2 in the Unprecedented Catalysis of the Sequential Pretreatment of Sustainable Agricultural and Agro-Industrial Wastes in Boosting Bioethanol Production

Improper lignocellulosic waste disposal causes severe environmental pollution and health damage. Corn Stover (CS), agricultural, and aseptic packaging, Tetra Pak (TP) cartons, agro-industrial, are two examples of sustainable wastes that are rich in carbohydrate materials and may be used to produce valuable by-products. In addition, attempts were made to enhance cellulose fractionation and improve enzymatic saccharification. In this regard, these two wastes were efficiently employed as substrates for bioethanol production. This research demonstrates the effect of disodium hydrogen phosphate (Na₂HPO₄) and zinc chloride (ZnCl₂) (NZ) as a new catalyst on the development of the sequential pretreatment strategy in the noticeable enzymatic hydrolysis. Physico-chemical changes of the native and the pretreated sustainable wastes were evaluated by compositional analysis, scanning electron microscopy (SEM), X-ray diffractometry (XRD), Fourier transform infrared spectroscopy (FTIR), and thermogravimetric analysis (TGA). These investigations showed major structural changes after the optimized sequential pretreatment. This pretreatment not only influences the delignification process, but also affects the functionalization of cellulose chemical structure. NZ released a higher glucose concentration (328.8 and 996.8 mg/dl) than that of ZnCl₂ (Z), which released 203.8 and 846.8 mg/dl from CS and TP, respectively. This work led to the production of about 500 mg/dl of ethanol, which is promising and a competitor to other studies. These findings contribute to increasing the versatility in the reuse of agricultural and agro-industrial wastes to promote interaction areas of pollution prevention, industrialization, and clean energy production, to attain the keys of sustainable development goals.     

基于USB接口的数据采集卡在UHT纸盒奶检测仪中的应用

UHT纸盒奶检测仪是基于流体力学的运动原理,利用电子、物理方法设计研制的,适用于不同砖型纸盒包装的超高温灭菌牛奶产品的虚拟检测仪器。本文介绍了在UHT纸盒奶检测仪中,在LabVIEW环境下,如何使用USB接口的数据采集卡,进行数据采集以及控制步进电机。通过试验证明该系统达到了设计要求。     

Pak Choi (Brassica rapa ssp Chinensis L) quality response to pre-harvest salinity and temperature

The effects of pre-harvest salinity levels (1.7, 9.5 and 12.3 mS cm⁻¹) and temperatures (18, 21 and 25 °C) on the ascorbic acid and total chlorophyll contents of Pak Choi (Brassica rapa ssp. Chinensis L) were investigated. The relationships of these chemical contents with storage period (0, 7 and 14 days) and water loss were also monitored. Increased production temperatures significantly (p < 0.001) reduced the ascorbic acid and total chlorophyll (p < 0.01). Ascorbic acid content in leaves grown at various salinities was significantly (p < 0.01) reduced beyond 9.5 mS cm⁻¹. Total chlorophyll was not affected by these different levels of salinity. Ascorbic acid contents of harvested shoots fell rapidly during the first seven days of storage, most markedly in shoots taken from plants grown at high salinity. The pattern of chlorophyll degradation depended on the plants' production environment where higher temperatures resulted subsequently in rapid degradation during storage. For shoots grown at high salinity, the chlorophyll content was sustained during early storage. Linear relationships were apparent between water loss and ascorbic acid and total chlorophyll contents of shoots from the range of treatments. © 1999 Society of Chemical Industry     

巴帕南水闸工程双扉闸门设计

泰王国巴帕南水闸及附属建筑物工程双扉闸门的设计具有代表性和特殊性，在双向挡水条件下，双扉闸门门叶及门槽埋件结构形式，水封的截面形状与布置方式，双扉闸门的防腐设计，启闭设备的布置和设计，以及双扉闸门操作运行方式等，能为类似工程提供经验。     

高速利乐包分切机的开发与设计

通过对分切机主要功能参数介绍以及对放卷装置、恒张力控制、热接装置、分切机构、收卷形式、拔轴器等部件结构特点和原理的详细分析,系统而有力地论证了本公司自主研发设计的高速利乐包分切机的科学性和先进性,完全可以替代国外同类产品,满足国内厂商实际生产要求,同时具有明显价格优势。     

铝塑苯醇水法分离的工艺研究

对利乐包中铝塑复合材料的分离工艺进行了研究。采用苯醇水混合液作为分离剂,分析铝塑分离机理。将苯醇水按照一定的体积比混合作为铝塑分离剂,优化了分离剂的体积比、分离温度等分离参数。结果表明：当分离剂中各溶剂的体积比为V（苯）：V（无水乙醇）：V（水）=50：20：50,温度60℃时铝塑分离效果最佳,铝塑总得率可达97％,并且废液处理简单,对环境污染小。     

利乐与康美包无菌灌装设备的分析

对利乐系列和康美系列两种典型的液体食品无菌灌装设备进行比较分析,从包装材料、包装盒的成型、包装工艺过程等不同角度阐述了二者的特点及应用场合。     

青菜中叶绿素含量的无损检测法研究

研究了扫描仪、色差计和叶绿素含量3个参数之间的相互关系。通过对叶绿素的标准溶液以及青菜样品的测定,寻找扫描仪的R、G、B、H2、I与色差计中的X、Y、Z、H1、L值及叶绿素含量之间的相关性。用扫描仪和色差仪对含叶绿素的样品进行测定。试验结果显示:扫描仪的R、G、B、H2、I值分别与色差计的X、Y、Z、H1、L值之间有极显著的相关性。青菜叶绿素含量与扫描仪的G与H2相关性极显著,相关系数r分别为-0.9395和0.9302;青菜叶绿素含量与色差仪的H1与L值相关性也极显著,相关系数r分别为0.9065和-0.9084。扫描仪和色差仪均适合对青菜色泽的测定。此外,可以根据回归方程,用G、H2、H1和L值计算叶绿素含量。