基于Mono Trap方法对酱油气味活性成分的分析

采用固相萃取整体捕集剂(monolithic material sorptive extraction,Mono Trap)结合热脱附、气相色谱-嗅闻-质谱(GC-O-MS)联用技术对高盐稀态酿造酱油气味活性成分进行提取分析.应用正交试验对Mono Trap方法中捕集剂的类型、萃取时间、萃取温度进行了优化,确定优化萃取条件为Mono Trap类型RGC18-TD、萃取时间60 min、萃取温度50℃.这一条件下能最大程度萃取吸附样品中的气味活性化合物,实验整体准确度和重复性良好.采用Mono Trap-GC-O-MS和SPME方法对高盐稀态酿造酱油气味活性化合物进行分析和比较,Mono Trap方法共鉴定出气味活性化合物56种,包括醇类9种、酮类5种、醛类7种、酯类9种、呋喃类6种、酚类3种、吡嗪类10种、有机酸类2种、含硫化合物4种、其他化合物1种;而SPME方法检测到55种气味活性化合物,且富集到的物质含量低于Mono Trap方法.与SPME方法相比,Mono Trap方法具有萃取量大、操作简便、回收率高等特点,在酱油的气味成分萃取上具有一定优势,有望成为今后酱油气味活性成分分析的研究方法之一.     

凝结水余压回水计算

重力回水和余压回水是凝结水回收最常用的2种方法，以往的设计往往忽视了余压回水，没有很好地利用蒸汽的动力。本文介绍关于疏水阀、回水管的相关选型方法，补充部分设计依据，指出一些认识上的误区，使设计人员能更好地了解系统运行特点，设计出简单、可靠的凝结水回收系统。     

The I-SPy Insect Indicator: an effective trap for the detection of insect pests in empty stores and on flat surfaces in the cereal and food trades

A new trap, the CSL I-SPy Insect Indicator^®, has been assessed for monitoring adults of the principal crawling beetle pests of stored products in empty premises and on flat surfaces in grain stores and flour mills in the UK.The new trap was compared with the Igrox Insect Monitoring Peanut-free Bait Bag, the Storgard^® Flit-Trak M² trap and the Pantry Patrol™ trap in laboratory arenas using six beetle species of important pest status or which might be difficult to trap. The Pantry Patrol trap performed least well. The I-SPy Insect Indicator containing a carob lure was as good as, or better than, the Flit-Trak M² trap containing both food oil and pheromone lures in catching Oryzaephilus mercator (81.0% and 51.1%, respectively), Typhaea stercorea (87.4% and 31.1%), Tribolium confusum (44.6% and 37.5%) and Cryptolestes ferrugineus (45.1 and 53.8%). For the Bait Bag the catches for these species were 67.2%, 59.5%, 55.7% and 81.9% respectively. The I-SPy Insect Indicator containing a carob lure and the Flit-Trak food oil was as good as the Flit-Trak M² trap in catching Sitophilus granarius (92.9% and 99.2%, respectively) and Rhyzopertha dominica (50.6% and 51.5%).In limited trials in premises with unknown levels of infestation, the I-SPy Insect Indicator containing the carob lure and the Flit-Trak food oil was at least as good as the Flit-Trak M² trap in a grain store. In a flour mill, the I-SPy Insect Indicator with this combination caught more species, higher numbers of insects and was better at demonstrating the presence of infestation. The I-SPy Insect Indicator is also sturdy, reusable, easy to assemble and leaves the catch easy to identify. Importantly, it contains no food which might act as a source of re-infestation.     

空压机转速波动分析与解决

介绍了某空压机组转速波动的情况 ,以及对该问题的原因分析和解决办法。经研究发现 ,该空压机中冷器凝析水疏水器平衡管存在工艺布置缺陷 ,并提出了改进方案     

数据挖掘技术在选择题难度客观因素分析子系统中的应用

回顾了现行选择题难度的预测方法，指出其主观性较强的缺陷。提出数据挖掘技术应用于选择题难度预测的设想．并对设想赋于实践，给出了选择题难度预测系统的体系结构图，最后较详细地说明了数据挖掘技术在客观因素分析子系统构建中的应用。     

Detailed study about influence of oxygen on trap properties in SiOxNy by the thermally stimulated current and maximum entropy method

The trap amount depending on trap energy levels [N_t(E_t)] in various silicon oxynitride films were investigated. Using the thermally stimulated current and the maximum entropy method, we determined N_t(E_t) with very high energy resolution. In N_t(E_t), many E_t were observed between 1.2 and 1.6 eV. Interestingly, their amounts significantly depended on the film compositions. The influence of oxygen on N_t(E_t) is also discussed.     

6110A柴油机排气微粒过滤器通过特性的研究

本通过大量试验，对所设计的６１１０Ａ柴油机排气微粒过滤器的背压随转速，过滤体孔隙率过滤体长度的变化规律及排气背压对柴油机功率，油耗的影响了系统的研究，根据排气背压，过滤效率选择了适合６１１０Ａ柴油机的过滤体。     

Thermally stimulated currents in a-Se99.5Bi0.5 thin films

The present paper reports on thermally stimulated current measurements in a-Se_99.5Bi_0.5 thin films at different heating rates (β₁ = 2.17 K/min, β₂ = 2.85 K/min, β₃ = 5.00 K/min). A well-defined TSC peak at a particular temperature has been observed which shifts toward higher temperatures (T₁ = 362 K, T₂ = 372 K, T₃ = 392 K) on increasing the heating rate (β). Using three different approaches the trap depth has been calculated giving good agreement with each other. The average value of trap depth is 0.29 eV. Trap density has also been calculated to be 6.62 × 10¹⁹ cm⁻³.     

应用人工合成烟青虫Heliothis assulta Guenee性信息素大面积诱蛾的研究

１９９３—１９９４年在河南等四省不同烟区用人工合成烟青虫性信息素进行大面积诱捕雄蛾试验研究，结果表明：人工合成烟青虫性信息素具有较强烈的生物活性，一个诱捕器每晚平均诱蛾９７头，最多１４８头。２个诱捕器间相距４０—５０ｍ，置于和烟株同高或高５ｃｍ处，每一诱捕器内设一诱芯等，为最佳条件。烟青虫雄蛾交配活动，夏季始于１８时，以２０－２２时诱捕蛾量为最多。文内提出今后大面积用于测报和防治的建议。