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954.
简要阐述了研制开发专用近红外光谱分析软件系统的必要性;介绍了中国农业大学研制的近红外光谱分析软件系统("CAUNIRS")的主要功能模块以及其功能特点;在"CAUNIRS"软件系统和结合行业专用需求的基础上,介绍了"复方中药专用近红外质量控制分析软件"和"近红外烟叶质量控制与配方设计专用软件"的设计开发模式;该软件系统的开发顺利完成了"十五"科技攻关项目"科学仪器研制与开发课题"中"专用近红外光谱分析仪研制与开发"子课题等项目中所要求的软件系统开发内容和任务. 相似文献
955.
Delong Cai Zhihua Yang Jingkun Yuan Xiaoming Duan Shengjin Wang Vaclav Ocelik D.I. Vainchteind J.TH.M. De Hossond Dechang Jia Yu Zhou 《Ceramics International》2018,44(2):1518-1525
In the present study, ablation behavior and properties of BN-MAS (magnesium aluminum silicate) composites impinged with an oxyacetylene flame at temperatures up to 3100 °C were investigated. As ablation time ranged from 5 to 30 s, the mass and linear ablation rates increased from 0.0027 g/s and 0.001 mm/s to 0.0254 g/s and 0.087 mm/s, respectively. A SiO2-rich protective oxide layer formed during the ablation process, which contributed to the oxidation resistance of the composites. Ablation products mainly consisted of magnesium-aluminum borosilicate glass, mullite, spinel and indialite. The thermal oxidation of h-BN during flame ablation and scouring of MAS by high-speed gas flow were the main ablation mechanisms. 相似文献
956.
Hainan Bai Jiulin Hu Xiaoguang Li Yusen Duan Feng Shao Takahiro Kozawa Makio Naito Jingxian Zhang 《Ceramics International》2018,44(6):6558-6563
Concerning the safety problems of conventional Li-ion batteries with liquid electrolytes, it is crucial to develop reliable solid-state electrolytes with high ionic conductivity. Li1+xAlxTi2?x(PO4)3 (LATP, x = 0.3) is regarded as one of the most promising solid electrolytes due to its high ionic conductivity and excellent chemical stability to humidity.Herein, a new strategy is proposed for improving the sintering behavior and enhancing the ionic conductivity of LATP by using LiBO2 as the sintering aid via liquid phase sintering. The as-prepared sample LATP with homogeneous microstructure and high relative density of 97.1% was successfully synthesized, yielding high total ionic conductivity of 3.5 × 10?4 S cm?1 and low activation energy of 0.39 eV at room temperature. It was found that the addition of LiBO2 could effectively enhance the densification and increase the ionic conductivity of LATP electrolyte, proving an effective way to synthesis LATP ceramics by a simple and reliable route. 相似文献
957.
Zhongren Zhou Yingjie Zhang Peng Dong Yixin Hua Qibo Zhang Ding Wang Jianguo Duan Zhen Zhang 《Ceramics International》2018,44(4):3596-3605
The molten salt electrolytic method for the preparation of titanium carbide and silicon carbide composites has been subjected to a systematic investigation by experimental analyses and thermodynamic calculations. It has been confirmed that the electrolysis of high titanium slag in the presence of mixed graphite powders generates intermediates CaTiO3, Ti2O3, TiO, Fe3Si and objective carbonous products TiC/SiC. It has been furthermore found that the deoxidization process depends critically on a number of process parameters, namely, electrolyte composition, graphitic regime, reaction temperature, cell voltage and reaction time. After careful optimization of these parameters, TiC/SiC nanocomposites with particle sizes of 10–174 nm has been produced by electrolysis of high titanium slag and graphite mixtures in molar ratio of 1:2 referred to Ti:C under 3.2 V at 900 °C for 6 h in 1 mol%CaO-CaCl2-NaCl molten salt and with particle sizes of 12 nm~207 nm in 1 mol%CaO-CaCl2 electrolyte. 相似文献
958.
Daxin Li Zhihua Yang Dechang Jia Xiaoming Duan Yu Zhou Dongli Yu Yongjun Tian Zihuan Wang Yinglong Liu 《Ceramics International》2018,44(4):3614-3624
Three types of SiBCN: carbon-lean, -moderate and -rich powders with the same Si/B/N mole ratio were subjected to high-energy ball milling to yield an amorphous structure. The effects of carbon content on microstructures, solid-state amorphization, surface characteristics and thermal stability of the as-milled powders were studied in detail. Results showed that the increases in carbon content can drive solid-state amorphization accompanied by strain-induced, crystallite refinement-induced and/or chemical composition-induced nucleation of nano-SiC from an amorphous body. The specific surface area increases as carbon content increases. The amorphous networks of Si–C, C–B/C–C, C–N, B–N and C–B–N bonds that compose the amorphous nature, but the species and contents of the chemical bonds are carbon content-dependent. Carbon-moderate powders possess satisfying thermal stability while carbon-rich ones perform the worst. Mechanical alloying derived SiBCN powders have outstanding oxidation resistance below 800 °C; however only carbon-moderate powders show desirable anti-oxidation ability at higher temperatures. Thus, mechanical alloying of SiBCN appears a suitable technique for developing amorphous matrix materials for practical applications. 相似文献
959.
基于小波高频分量的浮游植物活体荧光识别技术研究 总被引:1,自引:0,他引:1
提出了一种基于小波高频分量的浮游植物活体荧光识别技术。通过测量近海常见52种浮游植物的三维荧光光谱,利用小波函数将光谱分解6层后得到系列正交高频分量cd1~cd6,通过标准偏差选择稳定而特异性强的分量特征点及其组合作为浮游植物荧光识别特征谱,并对其稳定性和判别能力进行贝叶斯判别分析,以判别正确率为基准选择分量组合cd3~cd6作为最佳荧光识别特征谱构建浮游植物荧光标准特征谱库,结合非负最小二乘法实现了浮游植物群落组成门、属水平上的识别测定:单种浮游植物在门、属水平上的识别正确率分别为95.5%和85.7%;浮游植物混合样品(混合比例分别为100%,75%,25%)在门水平上的识别正确率分别为100%,90.9%,53.3%,平均识别相对含量分别为79.7%,68.3%,17.5%;优势藻(单种优势度达75%)在属水平上的识别正确率为81.2%。将该技术用于围隔实验和现场调查采集水样,有效实现了浮游植物在门水平上的定性定量识别测定。 相似文献
960.
介绍了高温高压水通过二次节流气液扩容分离和小孔变频扩散等多种方法,使排放时高达150dB的噪声降到50dB以下。 相似文献