Measurement Technology for Engine Assembly

In many industrial, it is often necessary to analyze the engine assembly. This paper introduces three kinds of new technologies on the assembly line of engine in recent years, it have played the positive role in improving the quality of assembling.     

直流蒸汽发生器建模与仿真研究

以B&W公司直流蒸汽发生器（OTSG）为对象,基于仿真支撑软件APROS平台中的基本模块,建立了图形化的直流蒸汽发生器模型;利用不同的APROS两相流计算模型进行仿真,对比分析后选取六方程计算模型;将2种模拟工况下的仿真结果与压降和传热系数经验关系式的计算结果进行对比,根据对比结果修正模型的压降和传热系数;将设定工况下的稳态及动态仿真结果与国内外实验数据对比,验证了本文模型的准确性。      

Dual Band Dual Polarization Directive Patch Antenna Using Rectangular Metallic Grids Metamaterial

In this letter, a kind of metamaterial superstrate based on rectangular metallic grids is presented to enhance the directivity of patch antenna at two frequency bands for two orthogonal polarizations. According to the periodic boundary condition, the influences of its important geometry parameters are investigated in detail by simulating its unit cell. It is found that the transmission peak frequency is intimately related to the size of rectangular metallic grid. Then, a dual band dual polarization patch antenna with metamaterial is studied and compared with conventional patch antenna. It is demonstrated that by introducing the proposed metamaterial superstrate, the gain of the patch antenna is improved by 9.5 dB at 14.1 GHz for x polarization and 12 dB at 15.4 GHz for y polarization, respectively.     

氧气厂低温冷却水系统结垢原因及解决方法

简述了氧气厂低温冷却水系统流程.通过对补充水水质、低温水系统流程、工艺控制条件等的研究,分析了低温水系统结垢原因,并提出了具体的解决方法.     

多巴胺改性聚苯硫脲与聚偏氟乙烯共混复合材料的制备与性能

聚苯硫脲（ArPTU）是一种新型高击穿、低损耗的材料,为提高其储能密度,在与聚偏氟乙烯（PVDF）共混的过程中,如何提高其溶解性,降低界面问题,成为研究热点之一。利用多巴胺（DA）对其进行改性可以有效地改善其与PVDF的界面问题。采用溶液流延热压的方法制备出不同共混比的多巴胺改性聚苯硫脲共混聚偏氟乙烯（DA/ArPTU-PVDF）复合薄膜。并采用X射线衍射仪、扫描电子显微镜、核磁共振、凝胶渗透色谱、阻抗分析仪等对其进行表征。结果表明:当DA/ArPTU-PVDF中DA/ArPTU质量分数为10wt%~15wt%时,PVDF的β晶型相对含量显著增加,这是其介电性能增加的主要原因之一;100 Hz时,介电常数最大可以达到10.3（10wt% DA/ArPTU）,同时介电损耗降低,最低达到了0.008（25wt% DA/ArPTU）。复合材料的储能密度也有明显提高,最大可以达3.0 J/cm3（10wt% DA/ArPTU）,相对于纯PVDF提高了63.3%。此外,复合材料的击穿特性相比于纯PVDF具有很大的提高,最大可达556.4MV/m（15wt% DA/ArPTU）。而且,改性后的复合材料力学性能也有了很大的提高。最大断裂伸长率可以达到196.7%（5wt% DA/ArPTU）,展现出了柔性高击穿储能材料的潜力。      

一种便捷、可视化的CO2驱助混剂评价方法——高度 上升法及其在油田化学中的应用*

在超临界二氧化碳提高石油采收率技术(CO_2-EOR)中,开发有效降低最低混相压力的助混剂是重要的一环。为有效缩短助混剂开发周期,大幅提高开发效率,介绍了一种便捷、可视化的最低混相压力测定方法——高度上升法。利用自行搭建的具有视窗的高压釜设备,将混相过程中油相的体积膨胀转化为高度信息,经数据处理获得混相百分比-平衡压力曲线,整个过程是可视化的,测得的最低混相压力与利用细管实验法测得的数据进行比对以确定准确性;提出了利用不同组成的模拟油进行助混剂筛选的实验方法。结果表明,高度上升法测定最低混相压力与细管实验法测定的相对误差小于5%。利用此方法筛选出了有效的八酯型助混剂,施用于长庆、新疆、吉林的原油样品时,在50数80℃、1%数3%用量下,均可有效降低最低混相压力,最大降幅超过20%。该方法可以准确测定最低混相压力,进而评价助混剂的助混效果。图4表2参33     

关键工艺点对四喜丸子软罐头高温蒸煮异味形成的影响

本研究利用电子鼻和顶空固相微萃取结合气质联用技术,探究四喜丸子软罐头加工关键工艺点的挥发性风味特征及变化规律,以确定其高温蒸煮异味（Warmed-over flavor, WOF）的形成机制。结果表明,高压蒸汽灭菌后的样品与其他组的风味轮廓存在显著性差异（P<0.05）;蒸制后的四喜丸子风味较好,而高压蒸汽灭菌后的样品产生显著的WOF异味（以亚麻籽油味和罐头味为主）（P<0.05）。此外,气味活度值分析结果表明,WOF关键异味分子为正己醛和庚醛;热加工过程中,这两种物质含量显著上升（P<0.05）,POV值显著下降（P<0.05）,TBARS值显著升高（P<0.05）,热处理促进四喜丸子中脂质的氧化降解。因此,本研究为四喜丸子软罐头工业化产品的异味形成和品质提升提供理论依据和技术支持。     

Moderate temperature sintering of BaZr0.8Y0.2O3-δ protonic ceramics by A novel cold sintering pretreatment

The state-of-the-art protonic ceramic conductor BaZr_0.8Y_0.2O_3-δ (BZY20) requires an extremely high sintering temperature (≥1700 °C) to achieve the desired relative density and microstructure necessary to function as a proton conducting electrolyte. In this work, we developed a cold sintering pretreatment assisted moderate-temperature sintering method for the fabrication of high-quality pure BZY20 pellets. BZY20 pellets with high relative density of ~94% were fabricated with a final sintering temperature of 1500 °C (200 °C lower than the traditional sintering temperature). A comparison with BZY20 control samples indicated that the proper amount of BaCO₃ introduced on the BZY20 particle surface and the high green density achieved by cold sintering pretreatment were the main drivers for lowering the sintering temperature. The electrical conductivity measurement by electrochemical impedance spectroscopy showed that the as-prepared BZY20 pellets have a proton conductivity comparable to the state-of-the-art values. The cold sintering pretreatment outlined in this work has the potential to lower the sintering temperatures for similar types of protonic ceramic materials under consideration for a wide range of energy conversion and storage applications.     

Photomemory and Pulse Monitoring Featured Solution-Processed Near-Infrared Graphene/Organic Phototransistor with Detectivity of 2.4 × 1013 Jones

Emerging graphene/organic phototransistors are eye-catching technologies owing to their unique merits including easy/low-cost fabrication, temperature independent, and achieving various functions. However, their development in the near-infrared (NIR) region is experiencing a bottleneck of inferior sensitivity due to low exciton dissociation efficiency and inefficient charge extraction rate. Here, a novel-design solution-processed graphene/organic NIR phototransistor is reported, that is, creatively introducing electron extraction layer of ZnO on graphene channel and employing organic ternary bulk heterojunction as photosensitive layer, successfully breaking that bottleneck. The phototransistor exhibits a high responsivity of 6.1 × 10⁶ A W⁻¹, a superior detectivity of 2.4 × 10¹³ Jones, and a remarkable minimum detection power of 1.75 nW cm⁻² under 850 nm radiation. Considering its excellent NIR detection performance, a noncontact transmission-type pulse monitoring is carried out with no external circuit support, from which human pulse signal and heart rate can be displayed in real time. The phototransistor, interestingly, can be switched into a photomemory function with a retention time of 1000 s in the atmosphere through a gate voltage of −20 V. The design takes the characteristics of graphene/organic phototransistors to a higher level, beyond the limit of sensitivity, and opens up a novel approach for developing multifunction devices.