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91.
文章提出用N2O-C2H2火焰原子吸收光谱法测定太阳电池材料用金中铁含量测定的研究。方法具有良好的灵敏度,干扰少,重现性好。铁量在1.0~10mg/mL范围内与吸收值呈良好的线性关系。其相对标准偏差小于1.0%。标准加入回收率在97.0%~98.0%(n=6)之间,适用于太阳电池材料用金中铁的质量控制分析和样品系统分析。 相似文献
92.
Developmental characteristics and response to iron toxicity of root border cells in rice seedlings
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Cheng-hua Xing Mei-hong Zhu Miao-zhen Cai Peng Liu Gen-di Xu Shao-hui Wu 《浙江大学学报(自然科学英文版)》2008,9(3):261-264
To investigate the Fe^2+ effects on root tips in rice plant, experiments were carried out using border cells in vitro. The border cells were pre-planted in aeroponic culture and detached from root tips. Most border cells have a long elliptical shape. The number and the viability of border cells in situ reached the maxima of 1600 and 97.5%, respectively, at 20---25 mm root length. This mortality was more pronounced at the first 1-12 h exposure to 250 mg/L Fe^2+ than at the last 12-36 h. After 36 h, the cell viability exposed to 250 mg/L Fe^2+ decreased to nought, whereas it was 46.5% at 0 mg/L Fe^2+. Increased Fe^2+ dosage stimulated the death of detached border cells from rice cultivars. After 4 h Fe^2+ treatment, the cell viabilities were _〉80% at 0 and 50 mg/L Fe^2+ treatment and were 〈62% at 150, 250 and 350 mg/L Fe^2+ treatment; The viability of border cells decreased by 10% when the Fe^2+ concentration increased by 100 mg/L. After 24 h Fe^2+ treatment, the viabilities of border cells at all the Fe^2+ levels were 〈65%; The viability of border cells decreased by 20% when the Fee+ concentration increased by 100 mg/L. The decreased viabilities of border cells indicated that Fe^2+ dosage and treatment time would cause deadly effect on the border cells. The increased cell death could protect the root tips from toxic harm. Therefore, it may protect root from the damage caused by harmful iron toxicity. 相似文献
93.
从结晶器设备构造、结晶器专家系统简介、结晶器液位控制、结晶器液压振动、结晶器在线调宽简介及故障处理等方面,介绍了太钢新炼钢连铸结晶器新技术及应用。 相似文献
94.
太钢质量管理工作的分析及对策 总被引:1,自引:0,他引:1
谢旭 《科技情报开发与经济》2008,18(32):220-221
介绍了质量管理的内容,分析了太钢质量管理的现状,探讨了太钢如何有效地进行质量管理的问题。 相似文献
95.
对燕山地带的河北兴隆蓝旗营冶铁遗址、河北滦平东沟冶铁遗址、河北赤城上仓冶铁遗址进行了田野调查,对采集的炉渣、炉壁、矿石等进行了实验室分析.通过初步研究发现三处冶铁遗址的性质比较接近,主要技术为生铁冶炼和炒铁,证明燕山地带的辽代居民掌握一定的生铁冶炼技术,并掌握了添加石灰石和白云石等作为助熔剂的技术,但综合冶炼技术不成熟.通过对比发现燕山地带辽代冶铁遗址的冶炼技术比较接近,随着遗址所处矿区的不同有一定的差异,初步印证了辽代的统治者对当时冶铁业进行了集中的管理,并且采取就近进行冶炼的作业方法. 相似文献
96.
97.
Alkaline treatment using sodium hydroxide was introduced to obtain a hierarchical pore structure in H-ZSM-5 zeolite.Fe-exchanged zeolite catalysts were prepared by impregnation on the original and alkali-treated zeolites,and were evaluated for NOx reduction by NH3,NO oxidation,and NH3 oxidation reactions.The highly dispersed iron species as active sites can be obtained by controlling the pore structure and particle size of zeolite.Therefore,the Fe/ZSM-5 catalyst treated mildly by sodium hydroxide before iron exchange,which contains amounts of highly dispersed Fe species,obtains over80% NOx conversion at a wide temperature range of 250-500℃. 相似文献
98.
钢铁冶炼中的温度是一个时变性、非线性的控制对象,很难对其构建准确的模型,采用数学模型技术在很大程度上无法得到准确的控制结果。为此,提出一种新的钢铁冶炼中的DCS波动温度稳定控制技术,给出钢铁冶炼炉DCS控制系统结构,介绍了钢铁冶炼中的DCS波动温度稳定控制原理,在PC机设定炉内最高温度后,下位机依据设定温度值令温度上升,通过模糊上升原理进行升温控制,达到设定温度值后,执行单神经元PID控制。将炉内温度偏差作为输入,将热电偶温度作为输出,通过单神经元PID技术进行DCS波动温度稳定控制。实验结果表明,所提方法稳定性和控制精度高。 相似文献
99.
Weijin Zhang Han Wang Hujun Cao Teng He Jianping Guo Guotao Wu Ping Chen 《自然科学进展(英文版)》2017,27(1):139-143
The effects of doping FeCl_3 on the LiNH_2-2LiH system were investigated systematically. FeCl_3 was prior to react with LiH during ball milling their mixtures. The metallic Fe, which is generated from metathesis reaction between FeCl_3 and LiH, plays an important role on improving the dehydrogenation kinetics of LiNH_2-2LiH system. The results indicated that the dehydrogenation peak and ending temperatures of the doped 1 mol%FeCl_3 sample shifted to low temperatures, and the dehydrogenation active energy changed from 102.45 k J/mol to 87.52 k J/mol. While increasing the amount of FeCl_3, an excess of LiCl, the by-product of metathesis reaction between FeCl_3 and Li H, can stabilize LiNH_2 and thus hinder hydrogen desorption. The dehydrogenation product is a new solid cubic phase solution of lithium imide-chloride. The high limit of the solid solution of LiCl and Li_2NH is near the molar ratio of 1:1. 相似文献
100.
YinQiu Cui ShiZhu Gao ChengZhi Xie QuanChao Zhang HaiJing Wang Hong Zhu Hui Zhou 《科学通报(英文版)》2009,54(21):3916-3923
Ancient mtDNA data of human remains were analyzed from four early Iron Age Tarim Basin sites (Yuansha, Zaghunluq, Sampula and Niya) in the southern Silk Road region. Haplogroup distributions show that ancient Tarim Basin population was comprised of well-differentiated Western and Eastern matrilineal lineages. Some West lineage of Tarim Basin population originated from Near East and Iran region. Of the East lineages, North and Northeast Asia originated lineages were the main components, and a few Southeast Asian lineages also existed, which indicated a more extensive origin and a more complex admixture. The genetic structure of ancient Tarim Basin population is relatively close to the modern populations of Xinjiang, which implied that the early Iron Age is an important period during the formation of the modern Xinjiang population. 相似文献