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盐湖卤水提取工业硼酸产业化新技术研究 总被引:1,自引:1,他引:0
制取硼酸的盐湖卤水化学组成复杂,文章仅就青海省西台吉乃尔湖卤水提硼生产工艺进行了探讨,研究了"硼硫"分步沉降分离工艺,和真空结晶器精制硼酸技术. 相似文献
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烟田土壤中有效硼的测定 总被引:9,自引:1,他引:9
提出了一种测定烟田土壤中有效硼的改进方法。该法用普通的聚乙烯瓶代替昂贵的石英三角瓶和石英回流器 ,在沸水中提取土壤中的有效硼 ,用等离子体原子发射光谱法代替姜黄素比色法测定提取物中的有效硼含量。方法的检出限为 0 .0 0 87mg/kg ,相对标准偏差为 6.5 5 %。采用该法对国家土壤有效态一级标准物质GBW0 74 12和GBW0 74 14中的硼进行了测定 ,测定结果与标准值接近 ,并采用该法测定了 2 0个土壤样品中的有效硼 相似文献
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过度金属离子的存在对硼酸盐中硼的测定有干扰,以往标准硼酸甲酯蒸馏分离法存在时间冗长,操作繁杂等问题。本文提出一简便易行的硼含量测定方法。该方法利用8—羟基喹啉掩蔽金属离子,在不分离金属离子条件下能够快速准确地进行硼含量的测定。 相似文献
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目的研究腐竹加工过程中硼的迁移情况,分析原料硼本底值与产品中硼含量间的关系。方法通过搜集腐竹生产企业的大豆原料、腐竹成品,以及实验室购买大豆并模拟腐竹生产,经微波消解后,采用电感耦合等离子体质谱法测定样品中的硼含量。结果大豆、豆渣、腐竹中都含有硼本底,且豆渣中硼本底较高,大豆原料至腐竹成品的硼含量迁移率约为35%。结论结合大豆硼本底值和大豆至腐竹的硼迁移率,建议腐竹中硼含量的本底值约为14 mg/kg。 相似文献
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Matt K. John 《Journal of the science of food and agriculture》1975,26(12):1911-1915
Optimum extraction ratio, acid normality, and shaking conditions were established for HCl extraction of boron from plant materials. Within the range of low boron tissue levels (below 50 parts/106) encountered in diagnostic analysis for boron deficiency, the HCl extraction compared favourably with the dry ashing method for determination of total boron in plant materials. Although extraction was incomplete from samples with high boron content (above 80 parts/106), total boron determined by dry ashing was closely predicted from extracted boron. A rapid, yet consistent, HCl extraction for diagnostic plant boron analysis is proposed. 相似文献
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Although boron wood preservatives have many advantages, boron itself does not adequately protect wood in ground contact and exterior applications because its susceptibility to leaching. As a result of previous studies to limit or decrease boron leaching, several fixation systems have been developed. In this study, we evaluated the effects of N′-N-(1, 8-Naphthalyl) hydroxylamine (NHA-Na) and hydroxynaphthalimide (NHA-H) on boron leaching and decay and termite resistance via possible boron precipitation in wood after NHA treatments at varying concentrations. Results showed that treatment of wood blocks with disodium octaborate tetrahydrate (DOT), boric acid (BA), or calcium tetraborate (CaB) incorporation with 1.0% NHA-Na solutions in sequential processes appears to somewhat reduce the susceptibility of boron to leaching. Blocks treated sequentially with boron compounds and then 1.0% NHA-Na solutions showed about 30% less boron leaching compared to boron only treated blocks. In addition, the existence of boron and NHA-Na in wood together showed a synergistic effect against brown-rot fungus, Fomitopsis palustris. We conclude that the relationship between boron and NHA-Na concentration in wood as regards precipitation possibilities appears to be predictive for reducing boron leachability. 相似文献
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通过对云南曲靖烟区不同海拔植烟土壤有效硼和对应的烤烟硼含量的分析研究,得出该区土壤和烟叶中硼素分布的基本状况,在此基础上研究了土壤有效硼对烟叶硼含量的影响,并对不同海拔烟区的土壤有效硼含量和烟叶硼含量的分布特点进行了研究。结果表明:(1)曲靖植烟土壤有效硼平均含量基本处于适宜范围,平均为(0.46±0.25) mg/kg,但变幅较大(0.01~3.31 mg/kg);其中37.19%的土壤样本存在不同程度的缺硼(≤0.40 mg/kg)或硼含量偏高(>1.0 mg/kg),该地区能够满足优质烟叶正常生长发育所需的土壤有效硼含量土壤占62.81%,其余土壤需对硼素进行适当调整;(2)曲靖烟区烟叶的硼含量平均为(24.06±11.09) mg/kg,变幅为3.22~66.44 mg/kg,有81.42%的烟叶样本硼含量在10.00~40.00 mg/kg范围内;(3)研究表明烟叶的硼含量与土壤有效硼含量间呈极显著正相关关系;(4)在曲靖地区土壤有效硼和烟叶硼含量均表现出随海拔高度降低而逐渐降低的变化趋势,特别是在1300~1500 m的海拔范围内表现得尤为明显。 相似文献
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土壤培养条件下,研究缺硼对不同硼效率甘蓝型油菜品种及其相互嫁接植株下部叶片硼及其它矿质养分含量的影响。结果表明,缺硼条件下,硼高效油菜品种青油10号(QY10)下部叶片硼含量最高,低效品种Bakow(Ba)最低,嫁接植株介于高效品种与低效品种之间。推断甘蓝型油菜下部叶片硼含量受根系(砧木品种)和地上部(接穗品种)共同影响。硼对油菜下部叶片其它矿质元素影响的受控部位不完全相同,缺硼对氮、磷、钙和锌的影响主要取决于地上部,与根系关系相对较小,对钾的影响主要由根系决定,而对镁、锰、铁、铜的影响不明确,可能受地上部和根系共同控制。 相似文献
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目的检测浙江省部分水产品中硼的含量。方法在浙江省11个地市的超市和农贸市场采集部分水产品,按照GB/T 21918—2008《食品中硼酸的测定》的第二法测定样品的硼含量。结果共采集样品296份,硼检出率为66.2%(196/296),硼含量中位数、P25、P75和最大值分别为0.19、0.025、0.47和26.8 mg/kg。海水水产品硼检出率和硼含量高于淡水水产品。海水中甲壳类、鱼类、软体类硼检出率和硼含量差异无统计学意义(P0.05);淡水中甲壳类、鱼类硼检出率和硼含量差异无统计学意义(P0.05);淡水虾和淡水蟹硼检出率和硼含量差异无统计学意义(P0.05)。结论本研究淡水水产品均为活水产品,海水水产品均为冰鲜水产品,前者测得的硼含量可以认为是本底含量,而后者因不能确定是否人为添加了硼,故测得值尚不能认为是本底含量。因此,对于两种生活环境中水产品硼含量的比较尚不能确定不同生活环境(海水或淡水)会影响硼在生物体内的富集。本研究中淡水水产品硼含量的测定可为硼限量标准的制定提供一定的参考。 相似文献
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Boron fixation in wood: studies of fixation mechanisms using model compounds and maritime pine 总被引:1,自引:0,他引:1
The purpose of the research work reported in this paper was to study the kinetics and thermodynamics of reactions of some boron compounds with some simple wood model compounds and with maritime pine (Pinus pinaster Ait.). The wood model compounds were selected in order to reproduce in a simple way the possible reactions boron may undergo with wood. Two boron compounds were tested with the wood: sodium tetraborate decahydrate (borax) and boric acid. Boron containing solutions applied to wood and model compounds were tested in such a way that they could lead to the insolubilization of boron or to its chemical fixation. Thermodynamics of boric acid fixation on the wood surface was studied. Results suggest that, even though boron reacts faster with polysaccharides than with lignin, all reactions are very slow at 20 °C. Adsorption should be the preferential mechanism for the bonding of boric acid to wood. This weak bond explains why boron tends to leach out from wood in wet conditions after conventional preservative treatments. 相似文献