Effects of long-term application of different green manures on ferric iron reduction in a red paddy soil in Southern China

Dissimilatory Fe（Ⅲ） reduction is an important process in the geochemical cycle of iron in anoxic environment. As the main products of dissimilatory iron reduction, the Fe（Ⅱ） species accumulation could indicate the reduction ability. The effects of different green manures on Fe（Ⅲ） reduction in paddy soil were explored based on a 31-year rice-rice-winter green manure cropping experiment. Four treatments were involved, i.e., rice-rice-milk vetch （RRV）, rice-rice-rape （RRP）, rice-rice-ryegrass （RRG） and rice-rice-winter fallow （RRF）. Soils were sampled at flowering stage of milk vetch and rape （S1）, before transplantation （S2）, at tillering （S3）, jointing （S4）, and mature （S5） stages of the early rice, and after the harvest of the late rice （S6）. The contents of TFeHa （HCI-extractable total Fe）, Fe（Ⅱ）HCI （HCI-extractable Fe（Ⅱ） species） and Fe（Ⅲ）HCI （HCI- extractable Fe（Ⅲ） species） were measured. The correlations among those Fe species with selected soil environmental factors and the dynamic characteristics of Fe（Ⅱ）HCI accumulation were investigated. The results showed that TFeHc~ in RRF was significantly higher than those in the green manure treatments at most of the sampling stages. Fe（II）Ha increased rapidly after the incorporation of green manures in all treatments and kept rising with the growth of early rice. Fe（Ⅱ）Ha in RRG was quite different from those in other treatments, i.e., it reached the highest at the S2 stage, then increased slowly and became the lowest one at the S4 and S5 stages. Fe（Ⅲ）Ha showed oppositely, and Fe（Ⅱ）HCI/Fe（Ⅲ）HCI performed similarly to Fe（Ⅱ）HCI The maximum accumulation potential of Fe（Ⅱ）HCI was significantly higher in RRF, while the highest maximum reaction rate of Fe（Ⅱ）Ha accumulation appeared in RRG. Significant correlations were found between the indexes of Fe（Ⅱ）HCI accumulation and soil pH, oxidation-reduction potential （Eh） and total organic acids, respectively. In together, we found that long-term application of green manures decreased the TFeHa in red paddy soils, but promoted the ability of Fe（lll） reduction, especially the ryegrass; Fe（Ⅱ）Ha increased along with the growth of rice and was affected by soil conditions and environmental factors, especially the water and redox ability.

Shrinkage Behaviour of Spheroidal Graphite Cast Iron in Green and Dry Sand Molds for the Benchmarking of Solidification Simulation

The effects of metallurgical and processing parameters on the formation of shrinkage cavities and porosities in spheroidal graphite cast iron have been studied, considering the parameters of carbon equivalent, inoculation, casting modulus, mold type (green or dry) and pouring temperature within specific ranges of these variables. Based on the orthogonal experiments, the metallurgical and processing parameters of the minimum casting shrinkage and the maximum casting shrinkage were obtained, and the effects of metallurgical and processing parameters on the formation of shrinkage cavities and porosities in spheroids graphite cast iron castings were discussed. Finally, two regression equations relating these variables to the formation of shrinkage porosity were derived based upon the orthogonal experiments conducted.

Ultrasound enhancement of the reduction of the Basic Green dye in wastewater by cast iron

Dyes in wastewater are of particular environmental concern since they give an undesirable color to the waters, dye and their derivatives are harmful to human health and the environment （ Annadurai et al., 2002）. Due to their biological persistency, conventional biological treat-ment processes such as activated sludge process are ineffective for their removal（Shaul et al., 1991）. There is a need to develop effective methods for the degradation of such persistent organic pollutants, either to less harmful compounds or, more desirable, to their complete mineralization.

Bioavailability of Iron and Related Components in Cooked Green Leafy Vegetables Consumed in Cameroon

Green leafy vegetables (GLVs) are a potential source of iron to combat iron deficiency in iron deficient population. The aim of this study was to determine the bioavailability of iron in seven species of leafy vegetables (Solanumscrabrun, Venonia amygdalina, Cucurbita maxima, Amarathus hybridus, Colococia esculenta, Solanum macrocarpon and Telfairia occidentalis) consumed in Bamenda, Cameroon. A survey was carried out in 70 households in Bamenda, Cameroon to determine methods of preparation of these green leafy vegetables. Iron, antinutrients and vitamin C levels were determined using standard methods and the bioavailability of iron was determined using an in vitro dialys ability method. The vegetables used for the study were cooked with the addition of tomatoes, peanuts, melon seeds and soybean seeds. The loss of iron in GLVs was as a result of dilution caused by addition of the principal ingredients. The V. amygdalina cooked with soybean contained the highest level of iron (128.28 mg/100g). The S. scrabrum cooked with tomatoes had the highest Total phenolic coumponds of 0.91 g/100g;the C. esculenta recorded the highest with values ranging between 0.14 - 0.35 g/100g;the C. maxima cooked with soybean recorded the highest oxalate level (6.46 g/100g);and the vegetables cooked with melon seeds recording the highest in phytatelevels (70 - 1.63 g/100g). Vitamin C levels were highest in the S. macrocarpon cooked with tomatoes (199.96 mg/100g). Iron bioavailability was highest in A. hybridus cooked with tomatoes (28.09%). The iron bioavailability negatively correlated with phytates and positively with vitamin C. GLV consumed in Bamenda are good sources of iron whose bioavailability can be improved by using tomatoes in cooking.

Green tea extract and epigallocatechin 3-gallate reduced labile iron pool and protected oxidative stress in iron-loaded cultured hepatocytes

Cellular and mitochondrial damage can be caused by labile iron pool (LIP) and mediated by reactive oxygen species (ROS). Livers of the thalassemias have highly increased levels of LIP and ROS. Green tea extract (GTE) and epigallocatechin 3-gallatte (EGCG) can potentially protect liver inflammation, fibrosis and cancer due to their anti-oxidative and iron-chelating activities. We studied the effects of GTE and EGCG on intracellular LIP and ROS, and mitochondrial membrane potential (ΔΨm) in mouse hepatocyte and HepG2 cell cultures using specific fluorescent techniques. Treatment with GTE (12.5 - 25 mg/dl) and EGCG (25 - 50 μM) significantly lowered levels of ΔΨm in the mouse hepatocytes;however, combined treatment of 25 μM DFP with GTE and EGCG did not enhance the decrease of hepatic ΔΨm. The results showed that GTE and EGCG effectively removed the intracellular LIP and ROS, and relieved the mitochondria membrane collapse of the liver cells, suggesting a hepatoprotective effect of green tea extract and EGCG in the hepatocytes with iron overload. Their actions might be related to iron-chelating and free radical-scavenging capacities. Whether the effects can improve iron overload and oxidative stress in thalassemia patients remains to be seen upon further examination.

Anti-malarial effect of 1-(N-acetyl-6-aminohexyl)-3-hydroxy-2-methylpyridin-4-one and green tea extract on erythrocyte-stage Plasmodium berghei in mice

Objective: To examine the efficacy of 1-(N-acetyl-6-aminohexyl)-3-hydroxy-2-methylpyridin-4-one(CM1) iron chelator and green tea extract(GTE) as anti-malarial activity in Plasmodium berghei(P. berghei) infected mice.Methods: The CM1(0–100 mg/kg/day) and GTE(0–100 mg(-)-epigallocatechin 3-gallate equivalent/kg/day) were orally administered to P. berghei infected mice for consecutive 4 days. Parasitized red blood cells(PRBC) were enumerated by using Giemsa staining microscopic method.Results: CM1 lowered percentage of PRBC in dose-dependent manner with an ED50 value of 56.91 mg/kg, when compared with pyrimethamine(PYR)(ED50= 0.76 mg/kg).GTE treatment did not show any inhibition of the malaria parasite growth. In combined treatment, CM1 along with 0.6 mg/kg PYR significantly inhibited the growth of P. berghei in mice while GTE did not enhance the PYR anti-malarial activity.Conclusions: CM1 would be effective per se and synergize with PYR in inhibiting growth of murine malaria parasites, possibly by limiting iron supply from plasma transferrin and host PRBC cytoplasm, and chelating catalytic iron cstitutive in parasites' mitochondrial cytochromes and cytoplasmic ribonucleotide reductase. CM1 would be a promising adjuvant to enhance PYR anti-malarial activity and minimize the drug resistance.

焦炉煤气GLT络合铁脱硫绿色低碳系统性解决方案分析

焦炉煤气PDS脱硫的硫磺收率在50%~60%,副盐累积产生大量脱硫废液,仅仅络合铁催化剂应用在HPF装置上存在诸多问题。从GLT络合铁脱硫的化学原理和工艺原理出发,结合工业改造实际,GLT络合铁技术应用在焦炉煤气净化中形成了系统化成套解决方案,不仅解决了络合铁催化剂应用的适配性问题,而且将硫膏资源化的同时实现零废液外排。通过案例对比分析了不同技术路线的技术经济性,GLT络合铁技术系统性解决焦炉煤气脱硫存在的环保问题,显著节省投资和运行费用,极大降低煤气净化过程的二氧化碳排放。

内蒙古白云鄂博某低品位含铁岩矿磁悬浮联合分级流程工业试验研究

白云鄂博铁矿石储量巨大,缓解了国家铁矿石对外依存度过高的问题,同时也助力了包钢集团生产发展。但是在采矿过程中,产生了大量TFe品位低于20%的低品位含铁岩矿。对该类矿石,采用传统连续磨矿-磁选流程,在细磨至-0.074 mm粒级含量95%情况下,铁精矿品位最高只有60.8%,无法达到合格铁精矿质量要求;如果采用浮选流程,选矿经济性能不佳,故该部分矿石一直进行堆放未得到应用。本文通过对原矿性质进行分析,引入新型磁悬浮精选机作为磁选精选设备,同时设计三条全磁工艺流程进行工业试验,均可得到TFe品位64.5%以上的合格铁精矿,同时铁精矿中杂质元素K、Na、Si含量远低于浮选工艺流程。其中,自主开发的阶段磨选-磁悬浮联合分级分选流程,在细磨至-0.074 mm粒级含量95%情况下,最终可得到铁精矿TFe品位64.5%、磁性铁回收率95.07%的优良技术指标,分选效率高,效果好。现场应用后可实现白云鄂博低品位含铁矿经济性绿色利用,经济效益显著,同时极大地延长了白云鄂博铁资源的供给年限,对国家自有铁矿石产能接续、矿山自身可持续发展及资源绿色利用具有深远意义。

A Simple and “Green” Method for Synthesis of Magnetic Hollow Silica Spheres and Its ⁹⁹Tc^mLabeled Targeting Studies

The magnetic hollow silica spheres (MHSS) with uniform cavity size and shell thickness were prepared by a simple and “green” method using functionalized SiO2 spheres as templates. Magnetic particles (Fe3O4) were deposited on the SiO2 surface by varying the molar ratio of [Fe2+]/[Fe3+] and the molar concentration of iron salts. The obtained magnetic hollow silica spheres exhibited a super-paramagnetic behavior at room temperature. Scanning electron microscopy (SEM), transmission electron microscopy (TEM), and X-ray powder scattering (XRD) were applied to characterize the MHSS. Besides, their unit cell parameters are calculated according to results indexing to XRD, the MHSS sample prepared at 0.10 M iron salts and 2:1 molar ratio of [Fe2+]/[Fe3+] has a largest cell angle (β) of unit cell. Due to large hollow cavity space and super-paramagnetic characteristics, the inner amino-functionalized MHSS could be labeled with radioisotope 99Tcm to study the MHSS’s magnetic targeting distribution in vivo. These results indicate that the MHSS has potential in the magnetic targeted drug delivery system which reduces the damage to normal cells and improves the therapeutic effect of cancer.

含铁纳米纤维电极去除水中孔雀石绿

作为一种典型的三苯甲烷类染料,孔雀石绿具有降解难度大、对生态环境和人类危害大等特点,因此水中孔雀石绿的治理问题不容忽视。本工作借助静电纺丝技术和液相还原法,将纳米铁颗粒物负载于高度蓬松的PVA纳米纤维,制备高性能的含铁纳米纤维,并利用其作为第三维电极构建三维电极反应体系,考察三维电极体系中孔雀石绿的去除行为。结果表明,未接通电源时含铁纳米纤维对水中孔雀石绿具有良好的吸附效果,吸附行为符合准二级动力学模型;在三维电极体系中,含铁纳米纤维先借助吸附作用对水中孔雀石绿进行富集浓缩,然后通过电解作用同时实现孔雀石绿的降解和含铁纳米纤维活性位点的再生。在预吸附-电解40 min后,水中孔雀石绿的去除率超过了95%,且反应体系呈现出较强的pH值耐受性。

木材气凝胶负载纳米零价铁的绿色合成及应用研究

植物提取物还原制备绿色纳米零价铁因环境友好、反应条件温和、形貌可控等优势成为当前的研究热点。以生物质资源木材气凝胶为载体,以落叶松单宁为多功能反应平台,成功制备了一种可高效去除亚甲基蓝的木材气凝胶负载纳米零价铁复合材料,并探究了铁盐种类、pH值等对亚甲基蓝去除效果的影响。采用扫描电镜(SEM)、X射线光电子能谱(XPS)和傅里叶变换红外光谱仪(FTIR)对木材气凝胶负载纳米零价铁复合材料进行了表征。结果表明:该复合材料在4次重复使用后对亚甲基蓝仍具有85%以上的去除率,且该方法在多种农林废弃物基材上都具有适用性,是一种绿色、环保、高效的通用型方法。

提升风电消纳的绿氢钢铁冶炼系统动力学建模

富裕风电电解水制氢,耦合高污染的钢铁冶炼过程,既促进炼钢产业低碳转型,又可有效提升风电消纳能力。为了模拟绿氢钢铁冶炼对风电消纳能力的影响,综合考虑钢铁冶炼的可靠性、氢能发展的经济性以及风力发电的环境性,确定绿电-氢能-钢铁冶炼耦合系统内部交互关系和反馈机制;结合钢铁行业发展趋势和绿氢替代潜力,建立了提升风电消纳的绿氢钢铁冶炼系统动力学模型;同时考虑到政府支持力度与制氢技术的发展,构建差异化情景,分析不同条件下的氢能需求规模和风电消纳水平。基于新疆案例表明,加大氢冶金支持力度和提高制氢电解效率,能够有效提升钢铁行业的绿氢替代率并加速绿氢成本降低,进而实现风电的全额消纳,有效解决“弃风”难题。

钒钛铁尾矿制备绿色建筑材料的研究进展

钒钛磁铁矿是以铁、钒、钛为主的多金属元素共生的复合矿,在世界分布不均衡。中国是该矿石的主要产出国之一,该矿石分布在五个主要矿带。钒钛铁尾矿是钒钛磁铁矿选矿过程中产生的固体工业废弃物,是一种多金属伴生的铁尾矿。该尾矿在中国的堆存量巨大,富含很多有用化学组分,也被称为人工矿床。该尾矿以硅酸盐为主,主要化学成分是二氧化硅、三氧化二铝、氧化钙和氧化铁等,主要矿物是脉石矿物。国内外学者对其在绿色建筑材料综合利用方面做了很多有益探索,但总体来看,这些研究更多停留在实验室里。主要原因是(1)不同尾矿库甚至同一尾矿库的钒钛铁尾矿理化性能可能有较大差异,尾矿原料的稳定性不足;(2)受尾矿原料不稳定的理化性能影响,中试结果经常出现较大差异,难以实现规模化利用;(3)钒钛铁尾矿库大多地处偏僻,运输成本高,且缺乏高附加值的尾矿产品,规模以上企业因投入大产出小望而生畏。本文综述了钒钛铁尾矿在中国的地域分布和堆存量,重点研究了其化学组成、矿物组成、粒度分布和重金属浸出,分析了其作为主要原料在绿色建筑材料方面的研究进展,指出了存在问题并展望了发展前景。

钢铁冶金过程铁前工序绿色智能制造的进展与展望

“碳达峰”“碳中和”等一系列概念提出,推动钢铁行业绿色智能制造升级。钢铁冶金生产过程中,铁前前端工序需要消耗大量能源,加快研究钢铁冶金过程铁前工序绿色智能制造,符合可持续发展战略要求。文章研究了钢铁冶金过程铁前工序绿色智能制造的进展与展望,在掌握铁前工序与低碳冶金技术概念的基础上,从运行状态智能感知、运行参数智能控制、运行性能智能优化、钢铁冶金过程智能协同管控几个方面出发,分析了钢铁冶金过程铁前工序绿色智能制造技术要点,同时,强调了钢铁冶金过程铁前工序绿色智能制造发展前景与方向,有助于提升整个铁前全流程性能,且优化控制钢铁冶金过程铁前工序过程。

模拟绿色植被的颜料复配与光谱混合模型研究

模拟绿色植被的伪装材料设计,需要满足与背景“同色”和“同谱”的要求.将无机颜料铁黄与铬绿混合以消除蓝峰,再与水滑石进一步混合,制得具有水吸收峰的绿色伪装颜料.将所得的绿色伪装颜料与绿色植物进行光谱比较,其光谱相似度最高达93.95%.通过建立光谱解混模型对伪装颜料进行分析,其结果表明,铬绿/铁黄混合颜料与水滑石进一步混合后,总体上具有较强的非线性特征,且在局部波段具有较强的线性混合特征.

“双碳”背景下钢铁冶金专业人才培养策略研究

近年来,中国相继发布多个关于低碳减排的政策文件,展现出国家对低碳减排的重视。钢铁冶金行业作为典型的重工业行业,迫切需要进行绿色低碳转型,而这一目标的实现不仅要求在技术上革新,更需要培养出适应该转型的专业人才。因此,文章探讨了钢铁行业人才培养的新挑战和新需求,分析了高校钢铁冶金专业在“双碳”背景下的人才培养策略:一是全面优化人才培养模式,二是深化产学研合作,三是系统优化课程体系,四是建立完善教学评价体系,以确保教育内容与行业需求高度一致。通过此综合性的措施,培养能够推动行业绿色低碳技术发展的高素质人才。

“双碳”背景下绿色转型对钢铁企业财务绩效影响研究

2020年“双碳”目标的提出,彰显了我国走绿色低碳之路的决心与毅力。高能耗、高污染企业首当其冲,尤其是钢铁企业积极响应国家号召,开展低碳绿色转型。文章以归纳分析、实证分析等方法系统研究了目前钢铁企业在“双碳”背景下进行绿色转型的动因及路径,并选取2022年45家上市钢铁企业作为样本,根据这些样本的财务指标平均值来分析企业绿色转型是否对财务绩效产生影响,以此为其他高能耗、高污染企业提供借鉴。

“双碳”目标下钢铁行业绿色转型路径研究

在“碳达峰”“碳中和”的目标背景下,低碳绿色已逐渐成为未来全球产业发展的主旋律。钢铁行业作为资源消耗密集型产业和典型的高碳排放行业,未来要想实现钢铁工业的可持续发展,低碳绿色将是重要发展主题之一。然而,节能减排核心技术缺乏、产业链协同创新机制尚未建立、科学规范的环境保护长效机制缺乏、行业产能过剩等问题,阻碍了钢铁企业绿色转型的进程。因此,基于国内外绿色转型前沿理论及行业发展趋势,文章探讨了钢铁行业绿色转型的策略建议:维持市场供需动态平衡、提高绿色低碳技术水平、构建钢铁产品全生命周期管控体系、引领产业链全面绿色转型、健全相关政策。

纳米零价铁基复合材料的绿色制备与应用研究

以硫酸亚铁为铁源,葡萄籽提取液为还原剂,活性炭为载体和分散剂,采用原位还原绿色制备了活性炭负载纳米零价铁复合材料(AC/nZVI)。利用SEM、EDS、XRD、FT-IR对制备的材料进行表征分析。最后,研究AC/nZVI对水中硝酸盐污染物的去除效率。结果表明,实验成功制备了平均直径为100nm的纳米零价铁,并且均匀分散在活性炭的表面及内部。AC/nZVI对硝酸盐去除结果显示,硝酸盐的去除符合准一级动力学,在pH为2,浴比为1∶50,硝酸盐初始浓度为100mg/L,反应30min后,对硝酸根的去除率可达99.98%。同时,对降解后的AC/nZVI进行回收再利用,重复降解10次后,在最优参数下对硝酸盐的去除率仍达到97.85%。以上结果表明,以葡萄籽提取液绿色制备的AC/nZVI在去除硝酸盐废水处理中具有充分的可行性和良好的应用前景。

安徽开发矿业有限公司铁尾矿全资源产品化梯级利用研究与实践

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