心舒滴丸中丹参水溶性成分提取工艺研究

目的优选提取心舒滴丸中丹参水溶性成分的工艺条件。方法高效液相色谱法测定水煎煮液、醇渗漉液中丹酚酸B的含量；单因素试验法优选最佳提取工艺。结果最佳提取心舒滴丸中丹参水溶性成分的工艺为：渗漉法，14倍量30％乙醇浸渍12h。结论所选取的提取工艺条件合理、可行，丹酚酸B提取率高。     

电容传感器与LabView在内镶式滴灌管在线监控系统中的应用

在线监控系统可以有效的控制加工生产线的误差趋势，提高产品质量，并减少废品的产生。内镶式滴灌管是干旱地区的节水灌溉设备，其加工和打孔精度都有很高的要求。采用非接触式高精度电容测微仪和LabView对滴灌管生产线进行在线检测和控制。高精度电容测微仪通过A／D采集板将电压信号的微变传入计算机，然后利用LabView软件中的虚拟仪器、虚拟信号处理等模决进行实时数据采集、数据处理、误差超差报警及打孔控制等功能。详细论述了测控系统的原理、强噪声的排除及并口控制等关键技术。     

复方丹参滴丸人含药血浆中三

建立了复方丹参滴丸人含药血浆中三七相关代谢物的固相萃取-高效液相色谱-电喷雾离于坍质诸分析方法。采用固相萃取预处理样品，高效液相色谱梯度洗脱分离样品，电喷雾正离子模式测定，通过离子阱质谱的步进式碰撞功能，获得多级碎片信息。在人含药血浆的全扫描代谢谱中发现4个新的色谱峰。利用多级质谱提供的碎片离子信息，对其进行结构分析，推测其形成途径，发现4个色谱峰均由三七相关代谢物产生。该方法精密度、稳定性、重复性均符合测定要求，可用于对复方丹参滴丸人含药血浆中三七相关代谢物的进一步研究。     

Flame spread over horizontal and vertical wires: The role of dripping and core

Dripping of polymer insulations in wire fire has a potential risk of igniting nearby objects and expanding the size of fire, but has not been well studied so far. In this experimental study, dripping behaviors during the flame spread over horizontal and vertical polyethylene (PE) insulated wires were investigated without external airflow. Two different wire dimensions – core/wire diameter of 3.5/8.0 and 5.5/9.0 mm – and three different PE insulations were tested. To identify effects of the core, wires with solid copper (Cu) core, hollow stainless steel (SS) core, and without core were tested, and both core and insulation temperatures were also measured during the flame spread. Experimental results showed that the high-conductance copper core acted as a heat source downstream to increase the flame-spread rate. However, in the upstream burning zone, the copper core also acted as a heat sink to cool the molten insulation and reduce its mobility. Thus, the copper core extended the residence time of molten insulation inside the flame to facilitate the burning while reducing the dripping. Moreover, for the downward flame spread, the heating by the dripping flow of hot molten insulation dominated over the heating by the core. The downward dripping flow is driven by gravity while limited by the viscous and surface tension forces. Therefore, the limited dripping flow along the cooler copper core reduced the downward flame spread. The trend of results was also found to be insensitive to the type of PE insulation. This is the first time that within a single flame, the simultaneous dual effect of the heat source and heat sink for the wire core was observed, and the influence of dripping on the flame spread over the wire was discovered.     

Synthesis of a dripping agent based on lauric acid diethanolamide and delaying its migration in LLDPE films

ABSTRACT

Polymeric films are increasingly used in greenhouse cultivation because dripping agents can improve the hydrophilicity of film surface. Here, we summarize a way to a new reactive type dripping agent, lauric acid diethanolamide monoacrylate (AAL), which was synthesized by using acrylic and lauric acid diethanolamide as main starting materials. As-prepared AAL was separately grafted onto linear low-density polyethylene (LLDPE-g-AAL) and layered double hydroxides (LDHs-g-AAL) to prevent it from migrating. Accelerated dripping experiment results showed that the dripping time of LLDPE/LDHS-g-AAL and LLDPE-g-AAL films at 60°C was prolonged to 16 and 12 days from 8 days of ungrafted one, respectively.     

Prediction of cooking times and weight losses during meat roasting

In this work, a meat oven cooking model is developed, and its ability to predict three main process variables – evaporative loss, dripping loss and cooking time – is evaluated. Heat transfer is modelled by Fourier’s law, while the internal moisture content variation is modelled as a function of water demand, which depends on the water holding capacity of beef. Experimental cooking of semitendinosus muscle samples was carried out in a convective oven to obtain general information about the process and to assess the model accuracy. Simulations were done by means of the finite element method, using three-dimensional irregular geometries as simulation domains. The model predictions were in good agreement with the experimental ones; the average absolute relative error was 3.91% for cooking time prediction, and 7.96% for total weight loss prediction.     

微流控聚焦流液滴产生过程中的力学机制(英文)

Based on viscous drag-induced breakup mechanism, a simple model was proposed to predict the dripping drop-let size as a function of controllable parameters in flow focusing micro devices. The size of thread before breakup was also investigated through laminar flow theory. Experiments and numerical simulations by VOF are carried out simultaneously to validate the theoretical analysis, showing that droplet size decreases rapidly with the in-crease of the flow rate ratio and capil ary number.     

PE,EVA流滴减雾棚膜的开发与应用

概述了近年来PE、EVA流滴减雾棚膜的发展概况 ,讨论了流滴减雾机理 ,介绍了减雾剂的主要品种及其特性 ,指出了棚膜流滴减雾效果的影响因素和存在的主要问题 ,对流滴减雾体系和流滴减雾棚膜的开发应用提出了建议     

滚动轴承润滑方式的分类与选择

依据润滑剂供给轴承时的外观状态将润滑方式分为脂、油两大类润滑方式.并进一步将润滑油润滑分为油浴润滑、连续油流润滑、断续油流润滑、滴油润滑、弥散微滴与油雾润滑五种类型。对各种润滑方式的性能特点进行了分析,并对技术经济指示进行了综合评价,从而给出了滚动轴承润滑方式的选择原则。     

氧化铝对聚乙烯防雾滴薄膜性能的影响

以氧化铝作为减缓剂加入聚乙烯(PE)防雾滴薄膜中,通过对薄膜微观观察,发现氧化铝在PE中具有较好的分散性,与PE界面结合性能好.通过对PE防雾滴薄膜光学性能、力学性能及流滴性能等测试发现,当氧化铝含量为6％时,PE薄膜光学性能及力学性能最好,雾度达到10.8％,透光率达到92.3％,纵向拉伸强度达到25.3 MPa,断...