共查询到17条相似文献,搜索用时 93 毫秒
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利用水热法实验制备黄钾铁矾固溶系列样品AFe_3(SO_4)_2(OH)_6,其中A位置可以被K~+、Na~+和H_3O~+占据。此外,还制备近全钾占据的黄钾铁矾作为对比样品。对制备的黄钾铁矾群样品进行了拉曼光谱测试,黄钾铁矾的拉曼光谱分为羟基区(3000~4000cm~(-1))、硫酸根内部模式、点阵振动模三个主要部分,并对有异议的振动模的归属重新做了分析。利用拉曼光谱峰的数目以及频移,离子半径的大小、键长、键角的变化等信息,采用胡克定律分析了黄钾铁矾固溶系列A位置的离子替换作用。A位置离子的替换作用主要影响黄钾铁矾结构中OH基周围的环境,使得与羟基相关的振动模发生变化。 相似文献
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污泥生物淋滤过程中黄铁矾对重金属离子的吸附与共沉淀作用的模拟研究 总被引:4,自引:2,他引:4
生物淋滤处理可加速污泥中重金属(Zn,Cu和Cr)的溶出。但在淋滤后期,约有31%的已溶出的Cu2+被重新固持。并且,Cu2+浓度的再次下降与Fe3+沉淀形成黄铁矾的反应在时间上具有同步性。为阐明Cu2+固持机理,文章利用氧化亚铁硫杆菌的生物催化氧化作用,模拟生物淋滤环境在纯体系合成了黄铁矾。吸附试验表明,在pH 2.0~2.5的范围内(污泥生物淋滤过程中重金属溶出范围),黄铁矾对10 mg·L-1 Cu2+(该浓度与供试污泥生物淋滤中的Cu2+浓度相近)的吸附率低于9%,不能完全解释Cu2+的重新固持现象。共沉淀试验表明,Cu容易与黄铁矾形成共沉淀而掺入矿物的晶格。当Cu2+为10 mg·L-1时,约有44.6%的Cu2+与黄铁矾产生共沉淀而进入固相。可以认为,Cu与黄铁矾的共沉淀效应,是导致污泥生物淋滤后期Cu2+浓度再次下降的主要原因,黄铁矾对Cu2+的吸附只起极小的作用。 相似文献
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施氏矿物Schwertmannite的微生物法合成、鉴定及其对重金属的吸附性能 总被引:11,自引:2,他引:9
在K+缺乏的FeSO4-H2O体系(pH 2.5)中,利用氧化亚铁硫杆菌对亚铁的生物氧化作用,合成了一种新型羟基硫酸高铁矿物Schwertmannite(施氏矿物)。借助扫描电镜(SEM)、X射线衍射(XRD)、傅里叶转换红外光谱(FTIR)、电感耦合等离子体原子发射光谱(ICP-AES)等方法对其组成和结构进行了分析与表征,同时还对其重金属吸附性能进行了研究。结果表明,A.ferrooxidans LX5休止细胞可在2 d内将在FeSO4-H2O体系中0.2 mol·L-1 Fe2+全部氧化成Fe3+,溶液pH由起始的2.5下降至2.10,约有15%的Fe2+被转化成红棕色沉淀,余下85%的Fe2+氧化后以Fe3+形式存在于溶液中。鉴定结果表明合成的红棕色羟基硫酸高铁沉淀为施氏矿物。吸附试验表明,施氏矿物对重金属阳离子Cu2+,Zn2+与 Cr3+的吸附受pH的控制,吸附率随pH的升高而增加,约在6.0~7.0时达到最大吸附率。当溶液中三种金属离子浓度为50 mg·L-1时,最大吸持率分别为99.3%,99.4%与87.6%。 相似文献
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He-Ne激光、紫外线诱变氧化亚铁硫杆菌及耐砷菌株的选育 总被引:6,自引:0,他引:6
对适合氧化亚铁硫杆菌(Thiobacilus ferrooxidans)特点的诱变方法进行了研究:把菌体制成无铁细胞悬液进行小剂量、多次数的诱变.氧化亚铁硫杆菌菌株S1经多次紫外线和激光照射,并结合逐级驯化处理,最终选育出了优良耐砷菌株Sx,它能在含11g/LAs2O3的环境中生长,比出发菌株的0.7g/L提高了近14.7倍.在用该菌株进行浸矿的实验结果表明:浸矿能力良好,在同样是10%接种量时,浸出时间比出发菌缩短了一天,并且砷元素的浸出率由原先的76%提高至85.7%. 相似文献
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微波消化骨中钙、镁、磷、钾、钠、铁、锌和氟的测定 总被引:10,自引:0,他引:10
目前,微波消化技术广泛应用于分析化学领域,该技术与传统的样品消解方法(干法灰比、湿法消化)比较,具有简单、快速、省试剂、污染少、消化完全等优点。用原子吸收光谱法测定了骨中钙、镁、磷、钾、钠、铁、锌和氟等元素,除了氟、磷元素以外,加标回收率为66.40%-110.91%,变异系数(CV)为10%以内(0.32%-7.61%)。 相似文献
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Kiyoshi Nomura Masuo Takeda Takeshi Iiyama Hitoshi Sakai 《Hyperfine Interactions》2005,166(1-4):657-664
In order to confirm Mössbauer spectra of Jarosite, unidentified Fe3+ species (Fe3D3) and Fe2O3 found on Martian surface, some Jarosite specimens produced on Earth were characterized by 57Fe Mössbauer spectroscopy. For comparison, anhydrous ferric sulfate minerals, Mikasaite (Fe3+ 1.56Al0.44)(SO4)3, and Yavapaiite, KFe (SO4)2 were also measured. The thermal decomposition products of Jarosite and their hydration products were also traced by scattering Mössbauer spectra (CEMS and XMS). These data are useful for the identification of hydrous and anhydrous ferric sulfate phases on Mars, including Fe3D3. 相似文献
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以酿酒酵母为载体,常温下利用仿生法成功合成了CdS量子点。荧光发射光谱、紫外吸收光谱以及荧光显微镜照片证明,该方法合成的CdS量子点的荧光发射峰位置在443nm,在紫外灯下能发蓝绿色荧光。透射电子显微镜(TEM)表征结果表明,该仿生法合成的CdS量子点为六方纤锌矿结构。以荧光发射和紫外吸收光谱为性能指标,考察了酿酒酵母生长时期、Cd2+的反应浓度以及反应时间等条件对合成CdS量子点的影响。当酿酒酵母处于生长稳定期初期时,与浓度为0.5mmol.L-1的Cd2+共培养24h后所合成的CdS量子点荧光最强。实验中观察到,换液培养可有效提高酿酒酵母合成CdS量子点的产量。 相似文献
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Biological synthesis approach has been regarded as a green, eco-friendly and cost effective method for nanoparticles preparation without any toxic solvents and hazardous bi-products during the process. This present study reported a facile and rapid biosynthesis method for gold nanoparticles (GNPs) from Capsicum annuum var. grossum pulp extract in a single-pot process. The aqueous pulp extract was used as biotic reducing agent for gold nanoparticle growing. Various shapes (triangle, hexagonal, and quasi-spherical shapes) were observed within range of 6–37 nm. The UV–Vis spectra showed surface plasmon resonance (SPR) peak for the formed GNPs at 560 nm after 10 min incubation at room temperature. The possible influences of extract amount, gold ion concentration, incubation time, reaction temperature and solution pH were evaluated to obtain the optimized synthesis conditions. The effects of the experimental factors on NPs synthesis process were also discussed. The produced gold nanoparticles were characterized by transform electron microscopy (TEM), X-ray diffraction (XRD), energy dispersive X-ray (EDS) and Fourier Transform infrared spectroscopy (FTIR). The results demonstrated that the as-obtained GNPs were well dispersed and stable with good catalytic activity. Biomolecules in the aqueous extract were responsible for the capping and stabilization of GNPs. 相似文献
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N-硝基苯基脲化合物的合成与表征 总被引:2,自引:0,他引:2
一釜合成法合成了五个新的 N-硝基苯基脲类化合物 ,其产率分别为 4 6 .4 %、71.4 %、5 2 .3%、5 5 .4 %和 6 7.7% ,并通过元素分析、红外光谱 ,核磁氢谱对产品进行了结构表征 相似文献
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A simple method for synthesis of gold nanoparticles (AuNPs) using Aspergillum sp. WL-Au was presented in this study. According to UV–vis spectra and transmission electron microscopy images, the shape and size of AuNPs were affected by different parameters, including buffer solution, pH, biomass and HAuCl4 concentrations. Phosphate sodium buffer was more suitable for extracellular synthesis of AuNPs, and the optimal conditions for AuNPs synthesis were pH 7.0, biomass 100 mg/mL and HAuCl4 3 mM, leading to the production of spherical and pseudo-spherical nanoparticles. The biosynthesized AuNPs possessed excellent catalytic activities for the reduction of 2-nitrophenol, 3-nitrophenol, 4-nitrophenol, o-nitroaniline and m-nitroaniline in the presence of NaBH4, and the catalytic rate constants were calculated to be 6.3×10−3 s−1, 5.5×10−3 s−1, 10.6×10−3 s−1, 8.4×10−3 s−1 and 13.8×10−3 s−1, respectively. The AuNPs were also able to catalyze the decolorization of various azo dyes (e.g. Cationic Red X-GRL, Acid Orange II and Acid scarlet GR) using NaBH4 as the reductant, and the decolorization rates reached 91.0–96.4% within 7 min. The present study should provide a potential candidate for green synthesis of AuNPs, which could serve as efficient catalysts for aromatic pollutants degradation. 相似文献