共查询到18条相似文献，搜索用时 125 毫秒
1.
氧气作为氧化剂 ,直接氧化Fe(OH) 2 制备δ -FeOOH ,发现初始pH值对δ -FeOOH生成有显著影响。初始pH值越高 ,则氧化后pH值也越高 ,且Fe2 的转化率增大。若初始pH值在 8.7～ 9.1范围 ,生成纯相δ -FeOOH。用红外光谱对产物进行表征 相似文献
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氧气氧化氢氧化亚铁过程的研究——初始pH值对δ—FeOOH形成的影响 总被引：1，自引：0，他引：1
氧气作为氧化剂，直接氧化Fe(OH)2制备δ－FeOOH,发现初始pH值对δ－FeOOH生成有显影响。初始pH值越高，是氧化后pH值也越高，且Fe^2 的转化率增大。若初始pH值在8.7-9.1范围，生成纯相δ－FeOOH。用红外光谱对产物进行表征。 相似文献
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本文通过测量Co3Ti、 Ni3Al、 Fe3Al、 TiAl四种金属间化合物在氧气、氢气中在2×10-4/s形变速率下的拉伸性能，研究了
其在氢气中的室温环境脆性.研究结果表明，上述四利金属间化合物在H2中的脆化程度(用氢脆因子
IH2=[(δo2一δH2)/δo2]×100％表示)是不同的，其大小依次为Co3Ti＞Ni3 Al＞Fe3Al＞TiAl.其脆化程度的差异用金属间化合物中
基体金属对氢气的催化裂解作用的强弱进行了很好的解释. 相似文献
4.
Experimental study on the inhibition of biological reduction of Fe(Ⅲ)EDTA in NOx absorption solution
LI Wei WU Cheng-zhi ZHANG Shi-han SHI Yao LEI Le-cheng 《Journal of Zhejiang University. Science. B》2005,(10)
Scrubbing of NOx from the gas phase with Fe(Ⅱ)EDTA has been shown to be highly effective. A new biological method can be used to convert NO to N2 and regenerate the chelating agent Fe(Ⅱ)EDTA for continuous NO absorption. The core of this biological regeneration is how to effectively simultaneous reduce Fe(Ⅲ)EDTA and Fe(Ⅱ)EDTA-NO, two mainly products in the ferrous chelate absorption solution. The biological reduction rate of Fe(Ⅲ)EDTA plays a main role for the NOx removal efficiency. In this paper, a bacterial strain identified as Klebsiella Trevisan sp. was used to demonstrate an inhibition of Fe(Ⅲ)EDTA reduction in the presence of Fe(Ⅱ)EDTA-NO. The competitive inhibition experiments indicted that Fe(Ⅱ)EDTA-NO inhibited not only the growth rate of the iron-reduction bacterial strain but also the Fe(Ⅲ)EDTA reduction rate. Cell growth rate and Fe(Ⅲ)EDTA reduction rate decreased with increasing Fe(Ⅱ)EDTA-NO concentration in the solution. 相似文献
5.
Experimental study on the inhibition of biological reduction of Fe(Ⅲ)EDTA in NOx absorption solution
LI Wei WU Cheng-zhi ZHANG Shi-han SHI Yao LEI Le-cheng 《Journal of Zhejiang University. Science. B》2005,6(10)
Scrubbing of NOx from the gas phase with Fe(Ⅱ)EDTA has been shown to be highly effective. A new biological method can be used to convert NO to N2 and regenerate the chelating agent Fe(Ⅱ)EDTA for continuous NO absorption. The core of this biological regeneration is how to effectively simultaneous reduce Fe(Ⅲ)EDTA and Fe(Ⅱ)EDTA-NO, two mainly products in the ferrous chelate absorption solution. The biological reduction rate of Fe(Ⅲ)EDTA plays a main role for the NOx removal efficiency. In this paper, a bacterial strain identified as Klebsiella Trevisan sp. was used to demonstrate an inhibition of Fe(Ⅲ)EDTA reduction in the presence of Fe(Ⅱ)EDTA-NO. The competitive inhibition experiments indicted that Fe(Ⅱ)EDTA-NO inhibited not only the growth rate of the iron-reduction bacterial strain but also the Fe(Ⅲ)EDTA reduction rate. Cell growth rate and Fe(Ⅲ)EDTA reduction rate decreased with increasing Fe(Ⅱ)EDTA-NO concentration in the solution. 相似文献
6.
采用激光拉曼光谱(Laser Raman)和X射线衍射分析(XRD)等方法研究带锈铸铁经过不同周期干、湿大气腐蚀时锈层相的转变.带锈试样内、外层的激光拉曼光谱分析结果表明:试样内、外层腐蚀产物的相结构出现差异,外层主要由β、α、γ-FeOOH和Fe2O3,相结成,内层比外层还多出了Fe3O4相.X射线衍射分析结果表明:随着干、湿大气腐蚀周期的增加,腐蚀产物中β-FeOOH相逐渐增多,而α-FeOOH和γ-FeOOH两相变化不大. 相似文献
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在2005年高考试题中考查有关金属元素的内容比较多,分析发现,主要考查了铁、镁、铝、钠等知识,特别侧重对铁的考查·下面对试题中涉及到的金属元素知识和能力的考查进行归纳·一、考点归纳1·铁(1)Fe的性质,与水反应·(2)Fe2+的还原性·涉及的氧化性物质有Cl2;NO3-、H+;H+、MnO4-;NaCl O3以及Fe2+电解中的放电顺序·(3)Fe3+的氧化性·涉及与铁粉、I-的反应,被其他还原剂还原成Fe2+·(4)Fe3+的水解原理·(5)铁的氢氧化物的制取和碱的通性,红褐色沉淀生成,热不稳定性·硫化亚铁、二硫化铁与氧气的氧化还原反应·(6)以铁的化合价变化为… 相似文献
10.
研究UV254光照下,Fe(Ⅲ)-EDTA/H2O2对苯酚的催化光降解效能。首先考察反应时间、溶液初始pH值、Fe(Ⅲ)与EDTA的浓度比值对UV/Fe(Ⅲ)-EDTA催化光降解苯酚的影响,进而考察UV/Fe(Ⅲ)-EDTA/H2O2体系对苯酚的降解效能。结果表明:当溶液pH为7,Fe(Ⅲ)/EDTA浓度比值为1:1时,经过1h反应,UV/Fe(Ⅲ)-EDTA体系对苯酚的催化光降解效率达61.13%。在溶液初始pH为37时,UV/Fe(Ⅲ)-EDTA对苯酚的降解率均可达60%以上。在中性条件下,UV/Fe(Ⅲ)-EDTA体系添加H2O2后可把苯酚的降解率从61.13%提高到91.30%。反应前后溶液的紫外扫描光谱表明光降解过程中苯酚的苯环共轭结构被破坏。最后对UV/Fe(Ⅲ)-EDTA/H2O2体系催化光降解机理进行了初步探讨。 相似文献
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INTRODUCTION Nitrogen oxides (NOx) are significant airborne contaminants resulting from fossil fuels combustion. The use of metal chelate additives for combined re- moval of NOx and SO2 in FGD (flue-gas desulfuriza- tion) systems was investigated by several groups (Harriott et al., 1993; Tsai et al., 1989; Shi et al., 1996a; 1997). Fe(II)EDTA (EDTA, ethylenediami- netetraacetate) as an additive for removing nitric oxide (NO) from flue gas had been extensively stud- ied, with the … 相似文献
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Scrubbing of NO
x
from the gas phase with Fe(II)EDTA has been shown to be highly effective. A new biological method can be used to convert
NO to N2 and regenerate the chelating agent Fe(II)EDTA for continuous NO absorption. The core of this biological regeneration is how
to effectively simultaneous reduce Fe(III)EDTA and Fe(II)EDTA-NO, two mainly products in the ferrous chelate absorption solution.
The biological reduction rate of Fe(III)EDTA plays a main role for the NO
x
removal efficiency. In this paper, a bacterial strain identified asKlebsiella Trevisan sp. was used to demonstrate an inhibition of Fe(III)EDTA reduction in the presence of Fe(II)EDTA-NO. The competitive inhibition
experiments indicted that Fe(II)EDTA-NO inhibited not only the growth rate of the iron-reduction bacterial strain but also
the Fe(III)EDTA reduction rate. Cell growth rate and Fe(III)EDTA reduction rate decreased with increasing Fe(II)EDTA-NO concentration
in the solution.
Project (No. 20176052) supported by the National Natural Science Foundation of China and the Scientific Research Foundation
for Returned Overseas Chinese Scholars, Ministry of Education 相似文献
13.
双硫腙萃取滴定法快速测定矿石中的微量银 总被引：1，自引：0，他引：1
黄兆龙 《蒙自师范高等专科学校学报》2001,3(4):9-11
利用银与双硫腙生成稳定配合物的性质 ,在HNO3-NaAc缓冲溶液中 ,用双硫腙标准溶液对银进行萃取滴定 .Pb2 +、Cu2 +、Ni2 +、Co2 +、Fe2 +等离子的干扰 ,用大量EDTA掩蔽 ,Hg2 +等离子的干扰用水反萃取分离 .准确度与光度分析法相近 ,可测定低至 5 0g/T的银矿石 . 相似文献
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Ferrous chelate absorption is deemed a promising method for NO removal from flue gas, but the key problem is the difficulty to regenerate the absorption solution, i.e. the complexes of FeⅡ(EDTA)NO and FeⅢ(EDTA) in the solution. Two bacterial strains isolated recently from the sludge of the denitrification step of a municipal wastewater treatment plant could be applied effectively to regenerate the absorbent were Pseudomonas sp. and klebsiella trevisan sp. Pseudomonas sp. exhibited high reduction ability on FeⅡ(EDTA)NO and the klebsiella trevisan sp. was more suitable for FeⅢ(EDTA) reduction. 相似文献
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考察了在微波辅助技术的前提下32Fe ＋/Fe ＋摩尔比、氨水用量和微波功率变量因素对制备34Fe O 纳米材料的影响,并筛选出较优的制备条件。同时,对该样品进行X-射线衍射（XRD）和高分辨率透射电镜（TEM）扫描分析。其结果表明：（1）32Fe ＋/Fe ＋摩尔比1：1、氨水用量15mL、油酸钠1.00g、微波辐射功率200W 和反应30min 为制备34Fe O 纳米材料的最优条件;（2）根据Scherer公式计算,该样品的平均粒径为10nm～20nm,且样品微粒形状规则,近似球形,晶体形状较好,粒径大小较为均一;（3）通过对比研究制备34Fe O 纳米微粒的微波辅助合成法、共沉淀法和沉淀氧化法,从XRD谱图分析可知,用微波辅助合成法制得的34Fe O 纳米微粒的特征衍射峰明显,分散性好,且强度较高,说明该法所制得的34Fe O 微粒晶化度较高。 相似文献
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以水杨酸、8－羟基喹啉为配体与铁（Ⅲ）合成了一种新型未见文献报道的三元配合物,用元素分析、热重差热分析、红外光谱、紫外可见光谱等手段对其进行表征,确定其化学组成为[Fe（C7H5O3）2（C9H6NO）]。水杨酸脱质子以酸根形式与Fe（Ⅲ）离子成键,酚羟基不参与配位,而8－羟基喹啉以酚羟基氧和杂环上的氮原子双齿配位,形成五元螯环。采用分光光度法研究其对大肠杆菌生长的作用,并绘出其生长曲线,发现配合物浓度低于2 mmol· L^－1时,促进大肠杆菌的生长,高于2 mmol· L^－1时抑制其生长,浓度越大抑制作用越强,即配合物对大肠杆菌的生长具有双向生物效应。 相似文献
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采用绿色聚醚封端技术合成了含聚氧乙烯基重复单元的大分子单体烯丙基聚氧乙烯基羧酸,然后与丙烯酸在水相中通过自由基聚合反应合成了一种新型的双亲水嵌段共聚物阻垢剂,并深入研究了其在循环冷却水系统中阻碳酸钙和分散氧化铁的性能.实验结果表明该共聚物具有优异的阻碳酸钙和分散氧化铁性能,XRD表征表明加入无磷非氮的共聚物阻垢剂得到的碳酸钙晶体在方解石结构中混有了部分球文石结构,通过红外光谱、扫描电子显微镜和透射电子显微镜同样可以证实碳酸钙晶体结构的变化.提出了聚乙二醇链段与钙离子通过相互作用来抑制水垢形成的基本动力机理. 相似文献
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基于密度泛函理论,采用广义梯度近似下的交换关联泛函PW91和双数值极化函数基组DNP,对氧原子掺杂的铁团簇FenO（n=3～13）的稳定性和电磁特性进行了研究.相比于纯铁团簇Fen（n=3～13）,氧原子的掺入提高了团簇的结构稳定性和化学惰性;铁氧团簇的结合能随着原子数的增加而增加,除Fe10O外,团簇中氧原子的位置总是位于团簇的表面;通过计算FenO结合能的二阶差分发现,Fe6O,Fe9O,Fe11O团簇是相对稳定的幻数团簇,氧原子的加入使团簇的幻数发生了改变.在FenO团簇中总磁距与氧原子电荷转移的多少有关,当n＞7后,电荷转移量增加,磁距也随之增大. 相似文献