Chemical Forms of Heavy Metals in Carbonate-Derived Laterite and Enrichment of Its Iron Oxide Minerals

In this paper the seven-step continuous extracting method was employed in the studyof chemical forms of the six heavy metals Co, Zn, Pb, Cu, Cr and Mn. The result shows thatthe metals in the laterite are present in the chemical form of crystalline iron oxides andresidues, and they are transformed toward organic and exchangeable forms in the surface soil.Linear regression analysis indicates that the above heavy metals have a positive correlation withthe crystalline iron oxide minerals. The crystalline iron oxide minerals have a very importantrole to play in the enrichment of heavy metals, especially the solid components in the laterite.

Chemical forms and extractability of iron in sediments of three contrasting lakes of China and UK

Iron is a limiting factor for the eutrophication of lakes, especially those lakes that are enriched with phosphorus. Extractability of iron in sediments of West Lake and Taihu Lake in China and Lower Lough Erne in Northern Ireland of UK was comparatively investigated on the basis of analysing chemical forms of iron using different extractants. It was shown that extractable iron in sediments of the lakes was greatly different using various extractants. Reactive iron or easily released iron such as “active' iron oxides, total free iron oxide and water-soluble iron was not high, only accounting for 0.01%—0.15% of total iron. The efficiency of the extractants for exchangeable iron was decreased in the sequence 0.1 mol/L HCl DTPA+TEA mixed solution > 1 mol/L NH 4OAc > 0.5 mol/L MgCl 2 = 0.5 mol/L CaCl 2. It seems that the complexion of iron by organic matter was not strong because the concentration of organically bound iron was significantly lower than the concentration it was forecasted. Extractable iron is not entirely consistent with or dependent on total iron in lake sediments. To a certain extent, phosphate can inhibit the release of iron in sediments of the lakes. The selection of extractants is thus the first key step to evaluate bioavailability of iron in lake sediments.

Forms of Iron in the Phosphorites of Abu-Tartur Area,Egypt

The Campanian\|Maastrichtian phosphatic deposits in Egypt, called the Duwi Formation, comprise a part of the extensive Middle East to North African phosphogenic province of Late Cretaceous to Paleogene age. The province holds the greatest accumulation of phosphorites in the geological history, possibly in excess of 70 billion metric tons. The phosphate resources in Egypt alone exceed 3 billion metric tons. Two\|third of these three billions occur only in the Abu\|Tartur area.\; Among the phosphorite deposits in Egypt, the phosphorites of the Abu\|Tartur area are characterized by high contents of iron ranging from 3% to 7% with an average of 5%. The detailed mineralogical and geochemical studies on the Abu\|Tartur phosphorites revealed that iron is found in the form of pyrite, ankerite, clay minerals, microinclusions, and iron oxide. Pyrite, which is the major fraction, occurs as filling cement and partial to complete replacement of phosphatic grains and confined to the fresh phosphorites while iron oxide occurs as cryptocrystalline aggregates of red to brown particles and is confined to the weathered outcrops. Exclusive relations between pyrite in the fresh phosphorite samples inside the Abu\|Tartur mine and iron oxide in the equivalent horizon of the weathered exposure indicated that iron oxide was formed by the oxidation of pyrite as a result of weathering. All of these forms harm the quality of ore, manufacturing processes, and the produced phosphoric acid and fertilizers.

Iron and inorganic carbon in Liaodong Gulf sediments of Bohai Sea in China

Iron in seawater is an essential trace metal for phytoplankton that plays an important role in the marine carbon cycle. But most studies focused on oceanic iron fertilization in high nutrient low chlorophyll （HNLC） seawaters. A study of inorganic carbon （IC） forms and its influencing factors was presented in Liaodong Gulf sediments, and especially the influence of iron was discussed in detail. Inorganic carbon in Liaodong Gulf sediments was divided into five forms： NaCl, NH3·H2O, NaOH, NH2OH·HCl and HCl. The concentration of NaCl and NaOH forms were similar and they only occupied the minority of total inorganic carbon （TIC）. However, NH3 ·H2O, NH2OH · HCl and HCl forms were the principal forms of TIC and accounted for more than 80% of TIC. Especially, the percentage of NH3·H2O form was much higher than that in the Changjiang River Estuary and Jiaozhou Bay sediments. All forms of inorganic carbon were influenced by organic carbon, pore water, iron, pH, redox potential （Eh） and sulfur potential（Es） in sediments, moreover, the influences had different characteristics for different IC forms. However, the redox reactions of iron affected mainly active IC forms. Iron had little effect on NH2OH· HCl and HCl forms of IC which were influenced mainly by pH. Iron had a stronger influence on NaCl, NaOH and NH3· H2O forms of IC ; the influence of Fe^2＋ was higher than Fe^3＋ and its effect on NH3 ·H2O form was stronger than on NaCl and NaOH forms.

UBM STUDY ON DOUBLE-DIE IRONING PROCESS

The double-die ironing process is studied by means of UBM. The formulas of deformation load.contact stress on die surface, and tensile stress which acts on workpiece is obtained. Taking account of dirnensional accuracy, a new critical condition of limit reduction in cross section area is put forward for the flrst time. The test experiment indicats that results of theoretical analysis well accord with the actual conditions.[0]

Formation and properties of high Fe-content Fe-(B-Si)-Zr bulk amorphous alloys

The present work is devoted to the development of Fe-（B-Si）-Zr amorphous alloys with high glass-forming ability and good magnetic properties. Using the cluster-plus-glue-atom model proposed for ideal amorphous structures, [FeFe11B3Si]（Fe1-xZrx） was determined as the cluster formula of Fe-（B-Si）-Zr alloys. The glass formation and thermal stability of the serial alloys, namely, [FeFel^B3Si]（Fel_xZrx） （x = 0, 0.1, 0.2, 0.3, 0.4, 0.5, 0.6, 0.75, and 1.0）, were studied by the combination of copper mold casting, X-ray diffraction, and differential thermal analysis techniques. The maxima of glass-forming ability and thermal stability were found to occur at the compositions of [FeFe11B3Si] （Fe0.6Zr0.4） and [FeFe11B3Si]（Fe0.5Zr0.5）. The alloys can be cast into amorphous rods with 1.5 ram diameter, and upon reheating, the amorphous alloys exhibit a large undercooled liquid span of 37 K. The saturation magnetization of the [FeFe11B3Si]（Fe0.5Zr0.5） amorphous alloy was measured to be 1.4 T.

Level of Macronutrients and Microelements of Blood Plasma in Different Forms of Pulmonary Tuberculosis

By the method of atomic emission spectrometry with inductively coupled plasma, the content of macro and microelements in the blood plasma of 35 practically healthy people living in the Northern region of Azerbaijan and in the Nizhny Novgorod region of the Russian Federation was studied as well as of 23 patients with pulmonary tuberculosis with different phases of the disease. The elemental homeostasis of the blood plasma did not significantly differ depending on the region of residence, except for the potassium level (by 1.3 times greater for Russians) and strontium (by 10 times higher among the inhabitants of the Northern region of Azerbaijan). In patients with focal pulmonary tuberculosis, there were no significant differences in the content of elements in the blood plasma. With pulmonary tuberculosis, accompanied by decomposition processes, the content of calcium, copper, zinc and iron in blood plasma significantly increases in comparison with healthy people. Analysis of the level of these macro- and microelements can be used to determine the transition of the early form of pulmonary tuberculosis to infiltrative and/or cavernous forms, in which the patient becomes epidemiologically dangerous to others.

Carbon dioxide catalytic conversion to nano carbon material on the iron–nickel catalysts using CVD-IP method

The over-consumption of fossil fuels resulted in the large quantity emission of carbon dioxide （CO2）, which was the main reason for the climate change and more extreme weathers. Hence, it is extremely pressing to ex- plore efficient and sustainable approaches for the carbon-neutral pathway of CO2 utilization and recycling. In our recent works with this context, we developed successfully a novel ＂chemical vapor deposition integrated process （CVD-IP）＂ technology to converting robustly CO2 into the value-added solid-form carbon materials, The monometallic FeNi0-Al2O3 （FNi0） and bimetallic FeNix-Al2O3 （FNi2, FNi4, FNi8 and FNi20） samples were synthesized and effective for this new approach. The catalyst labeled FNi8 gave the better performance, exhibited the single pass solid carbon yield of 30%. These results illustrated alternative promising cases for the CO2 capture utilization storage （CCUS）, by means of the CO2 catalytic conversion into the solid-form nano carbon materials.

铁枪考

历史上有不少用铁枪之人。铁枪通身是铁的纯杆铁枪,还是另有其他形制呢?文章通过对相关问题的研究,认为铁枪主要有七种形制:铁枪头之铁枪、铁鐏铁枪头之铁枪、铁杆铁枪、拒马枪、铁脊枪、木杆铁枪、铁盘槊。

云南新平米底莫铁铜矿成矿机理及找矿标志

米底莫铁铜矿床位于红河断裂与绿汁江断裂的三角区域,是不同时期构造-岩浆运动和变质作用的产物。为探索米底莫铁铜矿床成矿规律,在总结区域成矿背景、矿床地质特征的基础上,对矿化规律及控矿因素进行分析总结。研究表明:矿区出露早元古代大红山群,上覆晚三叠统盖层,总体为浅—中等变质的钠质火山岩系,其中大红山群曼岗河组是主要的含矿层位;矿区继承了区域构造-岩浆特征,火山喷发中心为火山气液、后期热液叠加部分,火山岩厚度自喷发中心往外逐渐减小,矿床富集程度也随之降低;区内大红山群岩系经受了浅—中等程度的区域变质作用,变质矿物主要为角闪石、绿帘石、铁铅榴石、黑云母等,并伴随着硅化、绢云母化、电气石化、钠长石化等围岩蚀变;矿床具有严格的成矿专属性,并受控于火山活动中心、火山喷发-沉积旋回及地质构造,邻近的火山机构及相似的地层岩性和近矿围岩蚀变可作为有力的找矿标志。

冀东司家营条带状含铁建造铁矿石铁同位素特征及其地质意义

司家营条带状含铁建造(Banded iron formation,BIF)型铁矿床是冀东地区规模最大的铁矿床,前人对其进行了大量的年代学、岩石学和元素地球化学工作,但目前尚未对其进行Fe同位素研究。笔者等通过Fe同位素和主微量、稀土元素相结合的方法对司家营BIF的成矿物质来源和形成背景提出了有效制约,同时对司家营BIF的锆石U-Pb年龄数据进行补充。锆石U-Pb年代学显示,司家营BIF形成于2537~2531 Ma。地球化学数据显示司家营BIF矿石主要由TFe_(2)O_(3)和SiO_(2)组成,具有较低的Al_(2)O_(3)和TiO_(2)含量,富集Fe重同位素(δ^(56)Fe=0.341‰~0.525‰);稀土元素配分模式呈现轻稀土亏损、重稀土富集的特征,具有明显的Eu、Y、La正异常,Y/Ho值较高(Y/Ho=34.96~45.84)。这些特征表明司家营BIF是基本无碎屑物质参与的化学沉积岩,稀土元素来源于高温热液和海水的混合溶液,铁质来源于海相热液流体。司家营BIF缺乏真正的Ce负异常和Fe同位素组成均为正值指示其形成于缺氧环境。综合对比世界上其他地区太古宙BIF的Fe同位素特征,笔者等认为新太古代时期地球海洋含氧量逐步上升,此时海洋总体属于缺氧环境,但部分地区氧气含量较高。

去除铸造盲孔环形铁屑的新型刀具设计

铸造阀体是工程机械液压阀生产制造的关键工序之一。针对工程机械液压阀机加工去除铸造盲孔环形铁屑研究,提出了一种去除铸造盲孔环形铁屑的新型阶梯成型扩孔刀具结构设计方案,指出了4个创新点,即环形铁屑去除效果好;刀具寿命长;刀具成本低;成型扩孔刀加工精度高。

辽宁翁泉沟硼铁矿田地质特征及成矿因素分析

翁泉沟硼铁矿床是辽东地区已知的特大型硼铁矿床,累计探明B_(2)O_(3)组分量2185万t,B_(2)O_(3)平均品位7.23%;共生的铁矿储量28302万t,TFe平均品位30.65%,固体硼矿储量居亚洲第一位。后期在其外围又相继发现了马家西沟和于家岭2个中型硼铁矿床,及3个小型硼铁矿床。这些矿床矿石类型以磁铁矿-硼镁铁矿型、硼镁石磁铁矿型为主,具有铁、硼矿产共生,普遍呈现含铀、富镁、贫钙和多硫的特点,是在火山-沉积变质作用的基础上,又叠加了变质热液交代改造作用形成的。根据矿体地质特征,重点分析翁泉沟硼铁矿田成矿因素,并对其成矿模式进行探讨,为该区进一步的勘查找矿提供新的思路。

冀东松木庄铁矿床地球化学特征及其地质意义

沉积变质型铁矿是冀东地区最主要的铁矿类型,松木庄铁矿床是该类型的典型代表。本次工作通过对区内矿石进行主量元素、微量元素、稀土元素测试,还原松木庄铁矿的成矿环境,同时分析其成矿物质来源。研究结果表明:此类型铁矿石的主要是成分是TFe_(2)O_(3)和SiO_(2),同时有少量的陆源碎屑岩加入,成矿物质来源于热水和海水的混合液。

KDF3滤棒成型机滤条成型装置改进

【目的】解决KDF3滤棒成型机组滤条成型装置设计不合理导致的滤棒圆周标准偏差sd值较大的问题。【方法】设计一种新型长圆弧外折叠板和一种新型直线式无台阶封口烙铁。【结果】应用改进的成型装置后,滤棒圆周标准偏差sd值降低24.3%,滤棒不圆度平均值降低13.2%;改进前后,生产阶段废品持平,变化不明显。【结论】改进的成型装置可为提高KDF3成型机滤棒圆周质量提供支持。

添加分散剂和造孔剂制备高密度磷酸铁锂正极

磷酸铁锂锂离子电池能量密度的提升,可促进其进一步应用。研究高面密度磷酸铁锂极片制备工艺,解决活性材料分布不均匀、孔隙率低和极化大等问题。在磷酸铁锂浆料中,加入的分散剂和造孔剂质量分数分别为0.6%和0.3%,极片压实密度为2.36 g/cm~3时,制成电芯的直流内阻最小(0.86 mΩ,50%SOC)。1.00 C倍率下恒流比和能量效率分别为98.87%和91.85%;以1.00 C倍率在2.50~3.65 V循环1 000次后,容量保持率为93.12%。

铁和硫的形态转化与水体黑臭的关系

介绍了黑臭水体概念及形成原因,分析了自然水体中铁与硫的赋存形态、转化过程和影响因素,阐明铁与硫的形态转化与水体黑臭的关系:以有机物为主的耗氧物质破坏水体中铁与硫循环因而造成Fe2+与H2S大量累积,出现水体黑臭现象。

不同铁形态对水稻根表铁膜及铁吸收的影响

通过溶液培养试验研究了FeCl2.4H2O和FeCl3.6H2O对水稻根表铁膜数量及铁吸收的影响。结果表明,FeCl2处理时水稻根表铁膜浓度是FeCl3处理的197%～233%。利用EDTA-BPDS对铁膜形态分析看出,根表铁膜中Fe3+占85%～92%,Fe2+占8%～15%。水稻天优998(TY998)根表铁膜数量显著高于培杂泰丰(PZTF),其铁吸收是培杂泰丰的115%～138%。两种铁形态处理明显提高了水稻的根系活力,其中,FeCl2处理时水稻根系活力增加24%～69%,FeCl3为16%～54%。FeCl2处理时水稻根系SOD、POD和CAT活性分别增加11%～32%、15%～30%和30%～31%,但FeCl3处理没有明显影响。上述结果表明,一定浓度铁处理明显增加水稻根表铁浓度和铁吸收;与FeCl3处理相比,FeCl2处理能提高根系抗氧化酶活性,增加水稻的铁吸收和根表铁膜数量。

吉林西部土壤铁形态分布及其与土壤性质的关系研究

对吉林西部三个主要农牧区(洮南市、通榆县和乾安县)50个表层土样进行测试,探究其土壤铁形态分布及其与土壤性质的关系。研究结果表明,其土壤铁形态的含量分布为:残渣态铁(A)>铁锰结合态铁(B)>腐植酸结合态铁(C)>碳酸盐态铁(D)>强有机结合态铁(E)>水溶态铁(F)>离子交换态铁(G),主要以A形式存在,且全铁平均含量均低于中国铁元素背景值。A与阳离子交换量(CEC)呈极显著正相关,B与p H值呈极显著正相关,C、E与有机质呈极显著正相关。A与土壤矿质元素的关系最为密切,C、D、G次之。各形态铁之间,B、C、D两两呈极显著正相关,其他形态铁彼此间关系不大。

石灰性土壤中铁肥的形态转化及其供铁机理研究

通过土培试验的方法 ,研究了复混铁肥、硫酸亚铁两种肥料在石灰性土壤中的形态转化、对土壤因子的调控作用及在有效性上的差异。结果表明 ,与硫酸亚铁相比 ,复混铁肥具有更强的调控土壤因子的能力 ,并提高了铁在有效和较有效形态中的分配 ,显著增加了有效铁的供给。结果也表明 ,交换态铁、碳酸盐结合态铁和氧化锰结合态铁是石灰性土壤中有效铁的主要供给形态。土壤pH值。