Key Engineering Materials Vol. 633

Abstract: Intelligent classification is realized according to different components of featured information included in near infrared spectrum data of plants. The core of this theory is to research applications of ant colony algorithm in spectral analysis of plant leaves through theories and experiments. In aspect of theoretical exploration, the built-in function of clustering algorithm is used to compress and process data. In aspect of experimental research, the near infrared diffuse emission spectrum curves of the leaves of Cinnamomum camphora and Acer saccharum Marsh in two groups, which have 75 leaves respectively. Then, the obtained data are processed using ant colony algorithm and the same leaves can be classified as a class by ant colony clustering algorithm. Finally, the two groups of data are classified into two classes. Our results show the distinguishability can be 100%. Keywords:Near infrared spectroscopy; ant colony algorithm; clustering algorithm; signal processing

Abstract: Due to its outstanding performance and merits, Self-Consolidating Concrete (SCC) has attracted a wide attention from scientists, researchers and engineers all over the world. At present, many research activities have been conducted in developing and evaluating SCC and its related technologies. However, existing performance evaluation methods of are mostly limited in the field of material, while structure performance evaluation methods of SCC are rarely reported. As we all known, the lifetime of the SCC structure is mainly subject to its material, structural and durability performances as a whole. Undoubtedly, it is crucial for us to study and develop a sound structural and durability performance evaluation method to complement the existing material performance evaluation methods. As such, the structural and durability performance evaluation method of SCC was studied in this paper.

Abstract: In this paper, the gas sensors using WO₃ as sensitive electrode, Pt mixed potential as the reference electrode was researched. The structures and preparation methods of the sensors were introduced. Besides, the sensitive materials, the electrode surface and the section morphologies were characterized by means of SEM and EDS. Furthermore, the sensing properties of the as-fabricated sensors were examined under different NO_X concentrations and temperatures (500°C, 550°C and 600°C). The results revealed that the response signal become smaller with the temperature increasing, and stronger with the increasing of the NO₂ concentration.

Abstract: The measurement of oxygen content in liquid iron and steel has been a challenge for decades and there have been many attempts to develop oxygen sensor to adjustment the smelting process on the basis of the probe for monitoring oxygen dissolved in molten liquid. However, there was still not a common standards of zirconium tubes about domestic product, which limited their application and improvement This work selected several domestic enterprises oxygen measuring half-cell system to study the relationship between the physical properties and microstructure at room temperature. Furthermore, we also analyzed about the typical performance of the domestic Oxygen content products, which would be beneficial to test and improve the quality of domestic products. Keywords: zirconia tubes, oxygen content, oxygen sensor

Abstract: Objective: A method based on high pressure digestion andinductively coupled plasma mass spectrometry (ICP-MS) detection was establishedfor determination of arsenic, mercury, lead, cadmium, chromium and thallium inbiological tissues. Method: The samplesof hair, nails, viscera, blood, urine were digested with HNO₃ and H₂O₂in high pressure digestion tank ; Indium was used as internal standard element,The certified GBW07601a (CRM Human Hair) was adopted as the quality control forthe whole processes. Results: Theexcellent sensitivity and reliability were demonstrated by the method ofrecovery 82% ~ 110%, RSD (n = 5) less than 5% and the linear range of 0.020ng/mL to 100 ng/mL (r > 0.99). The prototype measurements are within thescope of the standard value. Standard addition recovery of the six elements is therange of 92% ~ 105%. Conclusion: Arapid, easy and accurate quantitative ICP-MS method was established fordetermination of toxic elements in the human body, which enrich the existing meansof forensic technology. At the same time, this work provide the most practicaland reliable core data for poisons metabolism and pathological study.

Abstract: In this study, based on CIE L^*a^*b^* uniform color space, the Color i5 measurement instrument was used to measure the color parameters of seven blood amber samples under the D₆₅ illuminant. In addition, the influences of lightness variation of the non-color background on the lightness, the color saturation and the hue of the blood amber were also investigated and discussed. The results show that the lightness of the blood amber is significantly enhanced with the increased lightness of the non-color background and the blood amber with higher transparency is more sensitive to the change of the non-color background; the color saturation of the blood amber increases gradually with the raise of the lightness of the non-color background, which means that the blood amber on the high-lightness background looks more bright-colored than the one on the low-lightness background; the red color hue angle range of blood amber turns out to be diffusing with the increase of the lightness of the non-color background, which means that a slight difference of the hue can be more easily discriminated on the high-brightness background. Thus, it can be concluded that the blood amber with higher transparency is much easier to be influenced by the non-color background; and the increase of the lightness of the non-color background can lead to higher lightness, more bright-colored saturation and diffused hue angle range of the blood amber; and the blood amber is more bright-colored and the color difference can be more easily discriminated on the background with higher lightness.