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61.
62.
泸州老窖窖池是我国悠久文明史极为宝贵的文物 ,它是我国连续使用时间最长 ,保存完好并仍在继续使用的酿酒窖池。它不仅有宝贵的历史文物价值 ,还具有极为宝贵的科学研究价值和经济开发价值。早在二十世纪初四川军阀混战时 ,为争夺酒城泸州这个军事、经济、文化重镇 ,有的军阀就提出“打到泸州去 ,喝三百年老窖酒”的动员口号。解放以后 ,全国进行过五次评酒会 ,每次评酒会泸州老窖特曲都被列为国家名酒 ,泸州窖特曲也被确定为浓香型白酒的典型代表 ,这在众多的浓香型白酒厂家中 ,这是绝无仅有的殊荣。酿酒界业内人士都知道泸州老窖酒的生产… 相似文献
63.
随着我国新的《生活饮用水卫生标准》GB 5749-2006的颁布实施,相当数量的净水厂由于设施陈旧老化、处理能力不足、设计建造不够合理,或因水源变化、净水效果要求提高等多种原因,需要进行全面改造或局部改进。本文介绍了富兴堡水厂在原手动常规工艺处理方式下进行的自动化净水工艺的技术改造,着重论述了改造前后净水工艺控制方式的... 相似文献
64.
Tao Tang Kun Qian Tianyu Shi Fang Wang Jianqiang Li Yongsong Cao Qiongbo Hu 《Food Control》2011,22(8):1203-1208
Sufu is a nutritious fermented food whose consumption is currently increasing in many countries. The purpose of this study was to develop an HPLC method with SPE and pre-column derivatization for monitoring the content of biogenic amine in sufu and to understand the differences in the contents of biogenic amines with different processing technologies. Biogenic amines in sufu were extracted with 6% trichloroacetic acid, derivatized with 4-chloro-3,5-dinitrobenzotrifluoride, purified with Waters Oasis MCX cartridge, separated by HPLC using gradient elution, and detected by spectrophotometric UV at 254 nm. The method linearity, calculated for each biogenic amine, has a correlation coefficient higher than 0.9915. Detection limits of the biogenic amines were ranged from 0.016 mg/kg for putrescine to 0.067 mg/kg for spermine. Spiking experiments showed that the overall recoveries ranged between 83.6% and 103.5% with relative standard deviations of 1.26–5.24%. Of the seven biogenic amines under study, at least four biogenic amines were detectable in different kinds of sufu. Tryptamine, putrescine, histamine, and tyramine were the most prevailing biogenic amines in all sufu samples. The mean values of histamine, tryptamine, phenylethylamine, tyramine, putrescine, spermidine and spermine determined in samples were found to be 18.2 mg/kg, 39.0 mg/kg, 1.1 mg/kg, 21.7 mg/kg, 34.6 mg/kg, 11.1 mg/kg, and 8.7 mg/kg, respectively. The total contents of biogenic amines in bacteria fermented sufu samples (129.0 mg/kg) were slightly lower than those in enzymatically ripened sufu samples (137.7 mg/kg). The concentrations of biogenic amines detected in sufu samples were below the maximum permissible limits. 相似文献
65.
本文通过对中深孔爆破技术在我矿半煤岩巷掘进施工实际应用中的钻眼爆破方式、爆破参数、主要经济技术指标等进行综合分析和总结 ,提出今后推广应用中深孔爆破技术的最佳方案 ,应该注意的事项及采取的措施 ,对进一步提高单进水平 ,降低材料消耗具有一定的指导意义。 相似文献
66.
Xinge Zhang Mark Robertson Sing Yick Cyrille Dees-Petit Edward Styles Wei Qu Yongsong Xie Rob Hui Justin Roller Olivera Kesler Radenka Maric Dave Ghosh 《Journal of power sources》2006,160(2):1211-1216
The cathode is a key component in low temperature solid oxide fuel cells. In this study, composite cathode, 75 wt.% Sm0.5Sr0.5CoO3 (SSC) + 25 wt.% Sm0.2Ce0.8O1.9 (SDC), was applied on the cermet supported thin SDC electrolyte cell which was fabricated by tape casting, screen-printing, and co-firing. Single cells with the composite cathodes sintered at different temperatures were tested from 400 to 650 °C. The best cell performance, 0.75 W cm−2 peak power operating at 600 °C, was obtained from the 1050 °C sintered cathode. The measured thin SDC electrolyte resistance Rs was 0.128 Ω cm2 and total electrode polarization Rp(a + c) was only 0.102 Ω cm2 at 600 °C. 相似文献
67.
Shufang Wu Tianmo Liu Wen Zeng Shixiu Cao Kangguan Pan Shiyang Li Yongsong Yan Jiejun He Bin Miao Xianghe Peng 《Journal of Materials Science: Materials in Electronics》2014,25(2):974-980
Octahedral cuprous oxide has been synthesized by a simple hydrothermal method using copper sulphate and sodium hydroxide as raw materials in ethanol amine/distilled water mixed solution. The synthesized cuprous oxide powders were characterized by X-ray diffraction (XRD) and field emission scanning electron microscopy. XRD pattern exhibited that the nanocrystalline nature with cubic structure for the synthesized nanostructures. Analysis results reveal that pH value of solution plays an important role in the formation of octahedron shape for cuprous oxide. A probable formation mechanism of octahedral cuprous oxide is also proposed. 相似文献
68.
轻压下技术在高碳钢方坯连铸中的应用 总被引:4,自引:0,他引:4
台湾中钢、韩国浦项等5家钢厂在高碳钢方坯连铸中采用轻压技术之后,铸坯中碳和其它元素的中心偏析程度明显降低,缩孔和中心疏松缺陷也大大减少。从这些厂家的应用效果还可以看出,普通的轻压下技术,即机械轻压下技术用于小方坯连铸似乎存在一定的局限性,而热轻压下技术则为小方坯连铸提供了一种新的选择。 相似文献
69.
HPLC/UV analysis of chlorfenapyr residues in cabbage and soil to study the dynamics of different formulations 总被引:4,自引:0,他引:4
The chlorfenapyr analysis method of residue, its degradation and final residue in soil and cabbage were studied. Residues of chlorfenapyr were extracted from soil and cabbage with acetone/water, purified by liquid/liquid partition and chromatographic column, concentrated to a small volume, and then determined by HPLC equipped with UV detector. The mean accuracy of analytical method were 93.3% and 90.6% in soil and cabbage, respectively; the precision (repeatability) in cabbage ranging from 1.7% to 11.8%, in soil ranging from 2.8% to 11.2%; the precision (reproducibility) in cabbage ranged from 2.2% to 12.1%, in soil it ranged from 2.4% to 11.5%. The minimum detectable amount of chlorfenapyr was 0.65 ng, the minimum detectable concentration was 0.0162 mg kg-1. The degradation of chlorfenapyr formulations in soil and cabbage was determined. The results showed that chlorfenapyr nanoformulation and suspension concentration degradation in soil coincided with C=0.2538 e-0.1612t, C=0.537 e-0.1754t, respectively; the half-lives were about 4.3 d and 3.9 d, respectively. Two kinds of chlorfenapyr formulation degradation in cabbage coincided with C=4.0431 e-0.3103t, C=6.9611 e-0.2686t respectively; the half-lives were about 2.2 d and 2.6, d, respectively. When chlorfenapyr formulations were applied according to the double recommended dose, the final residues in cabbage were much lower than the USA EPA's maximum residue limit of 1 mg kg-1 in vegetables. The degradation rate of chlorfenapyr nanoformulation was faster than that of suspension concentration, and the former residue was also less in soil. Therefore, a harvest interval should be more than 5 d, and a dosage of 900 mL/hm2 was suggested for chlorfenapyr suspension concentration, which could be considered as safe to human beings and animals. Chlorfenapyr nanoformulation was safer than suspension concentration, its harvest interval and dosage can attain a high level. 相似文献
70.
鉴于现有几种应力测量方法在极高应力(岩体应力与强度比 >0.5)环境下的局限性,提出基于部分恢复变形的切缝解除法测量极高应力条件下岩体表面应力,并从理论模型上说明其确定极高应力的可行性。应用该方法对锦屏二级水电站科研试验洞开展实测研究,实测得到的最大应力可达80 MPa。该方法在测量过程中既不需获取完整岩芯,又不需要超高压力设备。测试设备轻便、操作简单,测量快速,适合于极高应力条件下表面应力测量,可为洞室岩爆防治、支护以及边坡治理提供实测地应力资料。 相似文献