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891.
对合成缓溶磷酸铵铜多元微肥的新方法进行了研究,以聚乙二醇-400 (PEG-400)为模板,CuSO4•5H2O和(NH4)3PO4•3H2O为原料,用低热固相反应一步法成功合成得到磷酸铵铜。用产物XRD图谱数据计算得到的信噪比作为试验的考察指标,试验中应用了均匀设计试验法及数据挖掘技术,在数据挖掘成果的指导下进行了试验。试验结果表明,用最优工艺条件合成得到的产物为51nm的NH4CuPO4 ∙H2O。该合成方法除了得到微溶的磷酸铵铜外,还得可溶的硫酸铵或者硫酸氢铵,这些产物均是肥料,故在实际应用中,用本文的合成法合成磷酸铵铜微肥时,无需分离,其产物混合物就可以作为肥料作用了,不仅合成的工艺甚为简洁,而且生产过程没有废水的产生,无论是从工艺上,还是环保上均比液相法具有优势,是一种颇具工业应用前景的合成法。 相似文献
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R.RAVISANKAR RESWARAN N.RSESHADERSSAN Bramaji RAO 《核技术(英文版)》2007,18(4):204-211
Element profiles of some beach rock samples collected from South East Coast of Tamilnadu, India have been determined using single comparator method of INAA. The geo-chemical behavior of the elements in the region is discussed. The irradiations were done at thermal neutron flux of ~ 1011 cm-2·s-1 at 20kW power using Kalpakkam Mini Reactor (KAMINI), IGCAR, Kalpakkam, Tamilnadu, India. Around 19 elements have been determined from 15 samples by high-resolution gamma spectrometry. The accuracy and precision were evaluated by assaying the irradiated Standard Reference Material (SRM 1646a Estuarine sediment) and were found to be in good agreement with certified values. 相似文献
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采用碳热还原方法、以不同掺碳(葡萄糖为碳源)方式合成LiFePO4/C复合正极材料,利用X射线衍射仪、高倍率透射电镜以及电池测试仪等手段对样品进行了分析研究,并探讨了不同掺碳方式对复合LiFePO4/C正极材料性能的影响.结果表明,采用湿法加入葡萄糖制备的LiFePO4/C正极材料中LiFePO4的粒径范围在40~80nm左右,为纳米材料尺度,0.05C倍率下首次放电比容量达到160mAh/g,1C倍率下循环50次后,容量衰减仅为1.2%. 相似文献
897.
The impact of 2 different brines on the palatability and tenderness of select beef strip loin steaks was evaluated. Brines were differentiated by the type of alkaline agent, 4.5% sodium-based phosphate (control brine; CON) or 1% ammonium hydroxide (ammonium hydroxide treatment; AHT), incorporated into the formula. Injected steaks were placed in high oxygen (80% O(2)/20% CO(2)) MAP, stored 4 d at 4 °C in dark storage to simulate transportation, and then placed in retail display. Steaks were selected randomly on day 0, 7, and 14 retail display to measure pH, cook loss, shear force, and sensory characteristics. The pH for AHT steaks (pH 5.96) was slightly higher than CON steaks (pH 5.86; P < 0.05). Cook loss was lower (21%) for CON than AHT steaks (23%). There was neither a treatment nor day effect on tenderness as measured by Warner-Braztler shear force (P > 0.05). Sensory evaluation indicated that on day 0, retail display the initial juiciness, sustained juiciness, tenderness 1st impression, tenderness overall impression, and connective tissue in AHT steaks was not different from CON steaks (P > 0.05). A day effect (decrease) for those sensory parameters was observed only for sustained juiciness (P < 0.05). AHT steaks were rated higher in cooked beef flavor while CON steaks were higher in peppery and salty flavor. There was no difference in soapy and ammonia intensity between treatments. Results indicated that despite lower performance in cook loss the replacement of 4.5% sodium-based phosphate in a meat injection brine with 1% ammonium hydroxide produced a beef loin steak with comparable tenderness and palatability. Practical Application: The research in this study compares steaks that have been injected with a commercial brine formulated with sodium phosphates to steaks that have been injected with a brine where the sodium phosphate in the formulation was replaced with 1% ammonium hydroxide. Ammonium hydroxide is an USDA-FSIS approved ingredient in brines injected into fresh meats. Successful replacement of sodium phosphate with ammonium hydroxide would allow processors to significantly reduce the sodium content of injected fresh meat. 相似文献
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