从锌冶炼净化渣中回收高品位铜精矿

锌冶炼净化渣先进行高温浸出,使锌、钴、镉等有价金属进入浸出液,而铜留在渣中,所得铜渣再经高酸浸出及水洗后得到铜精矿。结果表明,最佳高温浸出条件为:液固比(6⁷)∶1,始酸浓度100g/L、终点pH=3.0、807)∶1,始酸浓度100g/L、终点pH=3.0、80⁸5℃浸出8h;高酸洗涤最佳条件为:液固比(485℃浸出8h;高酸洗涤最佳条件为:液固比(4⁶)∶1,终点酸度50g/L,706)∶1,终点酸度50g/L,70⁸0℃浸出6080℃浸出60⁹0min。铜精矿含铜65%以上、含锌小于2%。     

石煤钒矿直接硫酸浸出工艺扩大试验

采用添加助浸剂直接硫酸浸出新工艺,针对某石煤钒矿开展了处理规模为1.2 t/d的扩大试验。结果表明,采用两段浸出,一段浸出为常温,浸出时间1.5 h,二段浸出温度为90℃、浸出时间8 h,在保持浓硫酸添加量为25%、助浸剂添加量均为2.5%时,钒浸出率稳定在86%左右,浸出效果良好;萃取选用6级萃取、1级洗涤、4级反萃、2级反铁流程,钒萃取率99%以上,反萃率98.6%;主要杂质元素铁、铝的萃取率分别为2%³%、12%3%、12%¹5%。     

铜阳极泥加压浸出液中硒碲分离的研究

先通过脱除铜阳极泥加压浸出液中大部分的铜离子,再进行分步还原分离硒、碲,进而达到高效分离硒、碲的目的,硒、碲分离率＞98%。该方法解决了铜阳极泥加压浸出液在沉硒过程中硒不能完全沉淀、影响硒的直收率指标、后续沉碲尾料中硒含量偏高不利于碲精炼提取的问题。     

Effect of drought and irrigation on the fate of nitrogen applied to cut permanent grass swards in lysimeters: Nitrogen balance sheet and the effect of sward destruction and ploughing on nitrogen mineralisation

Fuor years after ¹⁵N labelled fertiliser nitrogen (as Ca(NO₃)₂ and equivalent to 400 kg N ha^?1) was applied to permanent grass swards growing in lysimeter monoliths, approximately one-quarter remained immobilised in soil organic matter. In the intervening years similar but non-labelled applications were made. Although differing rainfall regimes applied during the experiment had significantly affected nitrogen uptake by plants and nitrate loss in drainage, they caused no significant effect on the tracer nitrogen remaining in the soil, the ranges were 85–97 kg N ha^?1 and 79–94 kg N ha^?1 respectively for the 135 cm deep clay and silt loam soil monoliths. Labelled nitrogen unaccounted for in crop, drainage or soil was presumed to have been denitrified. These losses averaged 62 and 49 kg N ha^?1 on the clay and silt loam soils respectively; again the differing rainfall regimes caused no significant differences. The ratio between estimates of labelled nitrogen denitrified and of annual nitroux oxide loss was approximately 9:1 for both soils. The conversion from permanent grass to winter wheat in autumn 1981, involving killing and then burying the sward, resulted in no pronounced increase in net mineralisation of labelled nitrogen. However, the balance between crop uptake and the quantity leached did change. Labelled nitrogen assimilated was less for the wheat (growing without addition of fertiliser nitrogen) than for the grass in its last year, and the quantity leached was considerably greater than under grass swards that were supplied with an average rainfall distribution. Following the first wheat harvest total nitrogen leached averaged 51 and 44 kg N ha^?1 on the clay and silt loam soils respectively. Rates of nitrous oxide emissions during the autumn following sward destruction were greater than in earlier years, but this enhanced loss was of short duration. The crop clearly benefited from the succession of nitrogen applications made to grass, as grain yield and total nitrogen uptake exceeded 7 t ha^?1 and 120 kg N ha^?1 respectively on both soils. These quantities exceed the national averages for winter wheat and are also considerably greater than for crops from lysimeters which received no nitrogen fertiliser throughout the experiment.     

硫化铜精矿的硫酸铵焙烧浸出

将硫化铜精矿与硫酸铵混合进行硫酸化焙烧,不仅有利于铜的浸出,而且硫酸铵分解出的氨用于提铜废酸液的中和处理,可以实现硫酸铵的循环利用。结果表明,在硫酸铵用量为1.5n(n为硫酸铵与黄铜矿的摩尔比)、420℃焙烧180min的条件下,铜硫酸盐化的效果最好,硫酸铵基本上完全分解,产生的氨97%左右可用稀硫酸液吸收。烧渣按液固比为4在80℃浸出90 min时,铜的浸出率可达89.96%。     

铁矾渣酸浸液磷酸除铁副产磷酸铁性能研究

针对本研究团队提出的"铁矾渣活化焙烧-稀酸酸浸-酸浸液磷酸除铁-除铁后液提In和Zn"新工艺,本文重点研究磷酸除铁滤渣物性及热分析动力学。通过XRD、IR、TG-DSC等对磷酸除铁滤渣的组成和物相进行分析表征。结果表明,磷酸除铁滤渣为FePO_4·2H_2O,滤渣平均直径12.6μm。采用FWO、KAS两种等转化率法求得滤渣磷酸铁水合物脱水反应的活化能为47.28～52.88kJ/mol。     

食品中氯丙醇污染及其毒性

氯丙醇类化合物,尤其是3-MPCD对酱油污染成为国际上关注食品安全热点问题之一。为了对该类物质有一全面了解,该文对食品中氯丙醇类化合物的种类、特性、来源、毒性、检测方法和预防措施及各国限量标准进行综述。     

The effects of soaking of whole, dehulled and ground millet and soybean seeds on phytate degradation and Phy/Fe and Phy/Zn molar ratios

The degradation and leaching of phytates, phytase activity and iron and zinc concentrations have been studied after soaking of whole seeds, dehulled seeds and flours of millet and soybean, in order to investigate the efficiency of soaking on reducing Phy/Fe and Phy/Zn molar ratios. When using millet grains, dehulling and milling before soaking facilitated the leaching of phytates and phytases in the aqueous medium and hence phytate degradation. Dehulling of soybean seeds led to a marked increase in phytate content, whereas milling favoured reactions between phytases and phytates. The Phy/Fe and Phy/Zn molar ratios decreased only slightly during soaking. The highest decreases for millet were obtained after soaking of flour for 8 h (Phy/Fe: 10.8–7.7 and Phy/Zn: 20.3–15.1), and after soaking of whole seeds for 24 h for soybean (Phy/Fe: 10.4–9.4 and Phy/Zn: 23.8–19.1). Cooking of flours with water used for soaking did not increase phytate degradation.     

食品中二噁英类化合物痕量检测研究进展

介绍二噁英类化合物的提取和净化方法,综述近十年来二噁英类化合物的化学分析法、生物检测法、免疫法及其它测定方法的研究进展,并对我国开展二噁英化合物的快速分析检测提出了建议和展望。     

Controlled delivery of lipophilic agents to cell cultures for in vitro toxicity and biocompatibility assays

Synopsis
In this report, we present a novel method for delivering lipophilic compounds to cell cultures. The delivery system is based on a nanoemulsion stabilized by phospholipids. These nanoemulsions are well tolerated by cell cultures, such as TK6 lymphoblastoid cells and can be used to deliver defined amounts of encapsulated lipophilic compounds into cells.
We measured the growth inhibition of TK6 lymphoblastoid cells caused by different oils, UV-filters and fragrances to determine the biocompatibility or the toxicity of these compounds in simple cell culture experiments. Our data show that the applied nanoemulsion technology is also very suitable to study biological effects of the UV-A-irradiated compounds in cell culture assays.
Résumé
Dans ce compte-rendu, nous présentons une nouvelle méthode pour dispenser des composés lipophiles à des cultures de cellules. Le système de répartition est fondé sur une nanoémulsion stabilisée par des phospholipides. Ces nanoémulsions sont bien tolérées par les cultures cellulaires, comme les cellules lymphoblastoides TK6 et peuvent etre employées pour délivrer des quantités précises de composés lipophiles encapsulés aux cellules.
Nous avons mesuré l'inhibition de la croissance des cellules lymphoblastoides TK6 provoquée par diverses huiles, des filtres UV et des parfums pour déterminer la biocompatibilité ou la toxicité de ces composés par des essais sur de simples cultures de cellules. Nos données montrent que l'utilisation de la technologie des nanoémulsions convient également à l'étude des effects biologiques des composés irradiés par des UVA dans les cultures cellulaires.