Application of the MIR for the determination of some chemical parameters in European Emmental cheeses produced during summer

This study examines the feasibility of using the mid infrared (MIR) spectroscopy for the determination of some parameters in European Emmental cheeses produced in summer from different geographic origins. A total of 72 Emmental cheeses (4 samples from Finland, 6 samples from Germany, 8 samples from Austria, 27 samples from France and 27 samples from Switzerland) were investigated. Total nitrogen (TN), water soluble nitrogen (WSN), non protein nitrogen (NPN), sodium chloride (NaCl) and pH were analysed by the reference methods. The MIR-transmission of the investigated cheeses was measured by a Nicolet Magna 750 IR spectrophotometer in a measurement range between 4000 and 400 cm⁻¹. The best results for WSN (R ²=0.80; ratio of standard deviation to root mean square error of prediction (RPD) =2.22), NPN (R ²=0.71, RPD=1.85), pH (R ²=0.56, RPD=1.50), NaCl (R ²=0.47; RPD=1.37) and TN (R ²=0.33; RPD=1.11) were obtained when the spectra were subjected to the first derivation and smoothing after being subjected to maximum normalisation. It can be concluded that the MIR-transmission spectroscopy could be considered as an alternative technique for the determination of NPN and WSN of Emmental cheeses originating from different European countries. The NaCl, pH and TN can also be estimated, but with much lower precision.     

四川盆地中西部地区须家河组碎屑岩储层特征及主控因素

四川盆地中西部地区须家河组储层为低孔低渗类型,储层非均质性强,储层发育影响因素复杂,主要为裂缝~岩性油气藏。为此,对该气田储层的控制因素进行了综合分析。结果认为,储层的分布主要受沉积环境(石英含量、碎屑粒度)、成岩作用、裂缝发育程度等因素的控制:裂缝对储层物性有着较大的改善作用;构造破裂作用对本区储层的储集性能有较大的改善,交代蚀变作用则对储层孔隙性的影响不大。     

Mid infrared spectroscopy and multivariate analysis: A tool to discriminate between organic and non-organic wines grown in Australia

The combination of mid infrared (MIR) spectroscopy and multivariate analysis was explored as a tool to classify commercial wines sourced from organic (ORG) and non-organic (NORG) production systems. Commercial ORG (n = 57) and NORG (n = 115) red and white wine samples from 13 growing regions in Australia were analysed using a MIR spectrophotometer. Discriminant models based on MIR spectra were developed using principal component analysis (PCA), discriminant partial least squares (DPLS) regression and linear discriminant analysis (LDA). Overall, the LDA models based on the PCA scores correctly classified on average, more than 75% of the wine samples while the DPLS models correctly classified more than 85% of the wines belonging to ORG and NORG production systems, respectively. These results showed that MIR combined with discriminant techniques might be a suitable method that can be easily implemented by the wine industry to classify wines produced under organic systems.     

城镇燃气中低压金属管道囊式不停输封堵施工技术

文章主要介绍了城镇燃气中低压金属管道不停输封堵技术的工艺原理、施工工艺流程、工程应用及其效益分析。     

Experimental investigation of lightweight residential floors supported by cold-formed steel C-shape joists

Presented in this paper are the experimental results of a recent study carried out at the University of Waterloo on vibration characteristics of cold-formed steel-supported lightweight residential floor systems. Laboratory tests were conducted for floors with different spans and assemblies to identify the critical parameters that contribute to the control of floor vibration. Both static and dynamic tests were carried out on the floor systems. On-site tests were also conducted in this study to substantiate the results obtained in the laboratory tests and evaluate the actual vibration performance of cold-formed steel-supported lightweight residential floor systems.     

串联谐振中频感应熔炼炉的技术综述

简述了当今各典型中频感应炉性能及优缺点，介绍了电压型串联谐振中频感应熔炼炉的选用２情况及国内应用的前景。     

非生物(无机)成因油气基础科学问题

为了更好地了解原油、沥青的成因,对克拉玛依油田沥青、塔里木盆地干酪根和沥青、辽河油田下第三系干酪根和沥青A以及原油进行了Pb、Sr、N d同位素研究,结果表明:准噶尔、塔里木和辽河3个盆地的沥青及原油的Pb同位素均显示出了壳-幔相互作用的特征,也均表现出不同于干酪根Pb同位素组成的特征(干酪根的Pb同位素组成明显表现出壳源的特征);克拉玛依沥青的Rb-Sr等时线年龄及初始Sr比值(87Sr/86Sr)I(即IO)与达尔布特断裂带附近金矿的成矿年龄和IO相一致,表明沥青与金矿的金均来自相同的深部源区。指出在准噶尔盆地通过深部地震测深所获得的中地壳低速层存在的信息支持了这样一个假说,油气可能为非生物(无机)成因。     

Kinetic and thermodynamic analyses of mid/low-temperature ammonia decomposition in solar-driven hydrogen permeation membrane reactor

It is a promising method for hydrogen generation without carbon emitting by ammonia decomposition in a catalytic palladium membrane reactor driven by solar energy, which could also store and convert solar energy into chemical energy. In this study, kinetic and thermodynamic analyses of mid/low-temperature solar thermochemical ammonia decomposition for hydrogen generation in membrane reactor are conducted. Hydrogen permeation membrane reactor can separate the product and shift the reaction equilibrium forward for high conversion rate in a single step. The variation of conversion rate and thermodynamic efficiency with different characteristic parameters, such as reaction temperature (100–300 °C), tube length, and separation pressure (0.01–0.25 bar), are studied and analyzed. A near-complete conversion of ammonia decomposition is theoretically researched. The first-law thermodynamic efficiency, net solar-to-fuel efficiency, and exergy efficiency can reach as high as 86.86%, 40.08%, and 72.07%, respectively. The results of this study show the feasibility of integrating ammonia decomposition for hydrogen generation with mid/low-temperature solar thermal technologies.     

明代中后期女袄的形制与结构特点解析

为对明代中后期女袄的形制与结构作进一步解读,以出土和传世的明代中后期女袄作为实物来源,结合墓葬简报与地方志等书籍资料进行分析研究,发现其形制与结构上的变化主要体现在领部、袖部、大身３ 个部位。通过对女袄领形、袖形、大身所具有的结构特征与变化的梳理,根据当时的社会状态和审美特征,总结了明代中后期女袄的形制特点与结构变化。揭示了其各部位的形制与结构变化规律：领子高度逐渐降低,领开口逐渐增大,衣袖部位袖底边曲度增加,大身部分尺寸愈加宽广,阐明了明代中后期女袄款式变化多样、继承与创新并存的特点,丰富了明代服饰文化研究成果。