快速测定油脂中的磷脂

对国际GB5537-1985进行改进，使测定植物油中的磷脂的速度提高1-2倍，可准确测定磷脂含量在5000mg/kg以下的各种植物油。     

1913t/h锅炉运行氧量优化试验研究

针对一台1 913t/h锅炉的热效率和排烟中NOx质量浓度问题,采用试验的方法研究了运行氧量对锅炉热效率和NOx生成的影响。结果表明:在保证锅炉安全经济运行的前提下,降低排烟中氧体积分数既可以提高锅炉热效率,又能降低NOx质量浓度;并推荐优化后的运行氧量曲线。     

加热器管子振动计算探索

随着新建机组容量的增大,高压和低压加热器等热交换设备也趋于大型化.加热器的换热面积增加后,使换热管的长度更长,因此,将造成换热管的振动加剧,所以,需要对换热管进行振动计算.美国热交换协会HEI的《动力厂热交换器标准》第四版叙述了换热管振动的计算方法.现以此计算方法为据,用实例进行了实际演算.该计算方法精简扼要,适用于设计加热器时的振动计算.     

树脂风轮在燃气热水器的应用

本文介绍了树脂风轮在燃气热水器的应用,对燃气热水器鼓风机使用树脂风轮,其风压、风量、噪音、消耗功率等方面的变化进行了试验分析,并在整机上的使用进行了相关测试,为树脂风轮在燃气热水器上的使用提供了参考依据。     

Variability of bovine conceptus-related volumes in early pregnancy measured with transrectal 3-dimensional ultrasonography

Up until now, bovine fetometry has been entirely based on 2-dimensional ultrasonography. Fetal size is estimated by several linear measurements such as crown-rump length (CRL). However, the advent of 3-dimensional ultrasonography (3D-US) provides in vivo access to the volumes of the fetus and its amniotic sac. The objective of this preliminary observational study was to determine the variability of conceptus-related volumes using transrectal 3D-US in dairy cows and to identify factors affecting them. Furthermore, relationships between the gained measurements and calf birth weight were investigated. In total, 315 Simmental and Holstein-Friesian dairy cows were transrectally examined at d 42 after breeding using a portable ultrasound device (Voluson I, GE Healthcare). Gestational volumes including fetal volume (FV) and amniotic sac volume (ASV) were determined with the software tool VOCAL (Virtual Organ Computer-Aided Analysis, GE Healthcare), whereas amniotic fluid volume (AFV) values were derived from the subtraction of FV from ASV. The CRL was determined by means of 3-dimensional data. The mean values and standard deviations for FV, ASV, AFV, and CRL were 1.47 ± 0.25 cm³, 5.86 ± 1.22 cm³, 4.38 ± 1.02 cm³, and 2.38 ± 0.18 cm, respectively. All gestational volumes and CRL values were affected by breed. In Simmental cattle, larger concepti were observed compared with pregnancies derived from Holstein-Friesian animals. Parity affected only ASV and AFV, with heifers showing greater values than lactating cows. The CRL was positively associated with milk protein content. It was not possible to predict calf weight at birth by using FV, ASV, or AFV; however, tendencies were found for ASV and AFV. The present study was the first to adopt 3D-US volumetry to assess early pregnancy development in dairy cattle. Our results showed that this method could be used successfully to identify minor variations in conceptus growth.     

气动量仪自动校对原理与仿真实验

针对气动量仪在人工校对过程中存在的问题,根据其自动校对原理,设计出一种自动校对机构。并以卷吸式差压气动量仪的内径测量为具体研究对象,结合实验和FLUENT仿真结果实证了自动校对的正确性和可行性。     

Optimization of baking parameters of part-baked and rebaked Irish brown soda bread by evaluation of some quality characteristics

Summary  Part-baked Irish brown soda bread loaves with bicarbonate levels from 0 to 2.8 % were baked, packed and stored for up to 11 days at 5 C then second-baked at 180 or 200 C for various times to give an oven-fresh end product. The quality of the rebaked bread was dependent on characteristics of the part-baked bread, its storage conditions and the processing parameters of the second baking phase. Quality parameters evaluated were bread volume yield, crumb and crust firmness, moisture content and colour. Staling of the part-baked bread during storage at 5 C and the reversion of this process at 59 C was investigated with regard to rebaking time and temperature. Rebaking conditions were optimized by evaluating the core temperature increase in the centre of the bread. Immediately after the second baking phase a post-baking temperature increase was measured which allowed reduction of the in-oven rebaking time. The data were modelled mathematically using least squares analyses.     

线性压缩机变容量性能实验研究

通过对开发的线性压缩机进行变容量调节性能实验,进行不同容量百分比条件下的效率分析.结果显示,当通过减小活塞行程实现变容量调节时,电机效率受频率特性的影响较大,在频率比接近1.0时,电机效率最高.绝热效率与活塞的摩擦损耗和吸排气阀开关损耗有关,随着活塞行程的增加,摩擦损耗也增加,但吸排气阀的开关损耗基本不变,绝热效率随着行程的增加先增大后减小.同样的行程条件下,排气压力越高,气体压缩功越高,但机械损耗不变,因而绝热效率越高.     

新型复合式露点间接蒸发冷却空调机组的试验研究

分析新型复合式露点间接蒸发冷却空调机组的芯体构造和工作原理。选择高湿度地区代表城市——福州,在7月份,对新型复合式露点间接蒸发冷却空调机组的工作电流和电压、机组风压、湿球效率、二/一次风量比、淋水量、耗水量等性能参数进行实际测试。结果表明:复合式露点间接蒸发冷却空调机组二/一次风量比为0.95时,机组的平均湿球效率为103%,机组在200L/h的淋水量下运行10min,需要消耗1.2L的水。将机组应用于一个室内模拟1kW发热源的房间,测试得到了机组运行的实际效果,并提出机组优化的试验参考。     

关于Veljan-Korchmaros定理的推广及其应用

推广了Veljan—Korchmaros定理，并应用它推广了n维Euler不等式。