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雨生红球藻(Haematococcus pluvialis)破壁方法对虾青素提取率的影响 总被引:2,自引:0,他引:2
采用匀浆法、冻融温差法、超声波法、直接研磨法和低温研磨法等5种破壁方法,研究了雨生红球藻提取虾青素时破壁方法对虾青素提取率的影响。结果表明,对雨生红球藻进行破壁是必要的。其中匀浆法、冻融温差法、超声波法、直接研磨法和低温研磨法等的最佳破壁条件为:匀浆法破壁时间22min,水为介质;冻融温差法破壁温度为-70℃,时间为12h,冻融2次,水为介质;超声功率400W,每次超声时间5s,共超声25min;直接研磨法研磨时间1min;加液氮低温研磨法破壁2次,每次时间0·5min;虾青素的提取率依次为0·76%、0·93%、1·03%、1·51%和3·21%。匀浆法和超声波法破壁由于要使用溶剂或介质,对后续的虾青素提取和分离会有影响,而直接研磨法在破壁过程中产生高温,降低了虾青素的生理活性,所以它们都不是雨生红球藻破壁的最佳方法。加液氮低温研磨法在破壁过程中不添加化学试剂,不产生污染,能最大限度地保留虾青素的生理活性,是所选方法中最好的一种。 相似文献
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对我国油气资源评价工作中常用的基本概念与评价方法进行了详细阐述,其中包括美国石油工程师协会(SPE)、俄罗斯和我国新实行的油气资源分类标准和基本概念;将油气资源评价方法分为:成因法、类比法、统计法、德尔菲(Delphi)法4大类;较详细的介绍了盆地模拟法、氯仿沥青“A”法、有机碳法、面积丰度法、体积丰度法、统计趋势预测法、油气田(藏)规模概率分布法、地质因素分析法、圈闭法等具体评价方法,并简要分析了它们的适用范围和特征。 相似文献
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风浪和涌浪分离方法的比较 总被引:3,自引:2,他引:1
海浪通常以风浪和涌浪混合的形式存在。文中利用模型试验和实测资料,对目前提出的一种二维谱风涌浪分离方法(2D法)和3种一维谱风涌浪分离方法(PM法、WH法、JP法)进行了检验,分析发现:2D法给出的结果整体而言最为可靠,与2D法相比,PM法明显高估了风浪成分,WH法低风速时高估了风浪,高风速时跟2D法比较接近,而JP法在整体上高估了风浪成分。通过调整分割频率的比例系数,改进了PM法,改进后的PM法给出的分离结果与2D法最为一致。 相似文献
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Doaa Hassan Youssef 《Journal of Oceanography》2003,59(5):537-544
Concentrations of boron in seawater (from four regions along the Alexandria coastline, subjected to land disposal), brackish
water (Lake Edku) and drains water (e.g. El-Umum Drain) were determined during the period from February to August 2000. Boron
was determined spectrophotometrically by a modified curcumin method. For Lake Edku, boron concentration fluctuated between
0.023 and 0.105 mmol/l. There are several factors that affect the concentration of B in the Lake water: (a) effect of the
drainage water via El-Khairy and Barsiek Drains, (b) utilization of boron by hydrophytes, and (c) water exchange through the
sea-lake connection. It may be concluded that the level of boron in the Lake water cannot be considered a substantial hazard
to the Lake organisms. Boron concentration varied from 0.392 to 0.522 mmol/l in seawater samples and from 0.141 to 0.458 mmol/l
in the sites where the water from the drains (El-Umum Drain and El-Noubaria Canal) mixed with the seawater. The broader variation
of boron (mmol/l)/salinity ratios for seawater samples (0.0106–0.0138) may be due to that the samples were collected from
the upper seawater layers, where contributions from land run-off, atmospheric precipitation and differences in the biota affect
the concentration.
This revised version was published online in July 2006 with corrections to the Cover Date. 相似文献
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To achieve greater precision and accuracy in the measurement of seawater boron concentrations, we propose a series of modifications to an established (curcumin) method based on the reaction of boric acid with curcumin. The modifications were derived from a series of experiments evaluating the stability of the curcumin–acetic acid reagent, the dependence of the reaction on temperature and duration, the effect of evaporation during the dehydration process, the interference of water, and the effect of sea salts. Application of the modified method to analysis of seawater samples collected from the Pacific Ocean indicated that it yielded considerably better precision and accuracy for boron concentration measurements than both the conventional curcumin method and other analytical techniques. 相似文献
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阴离子螯合树脂吸附硼的研究 总被引:3,自引:0,他引:3
用 Amberlite IRA-743和国产 564型树脂来吸附硼,研究了pH、硼的 浓度、温度、杂质高子等因素对吸附的影响。结果表明:两种树脂皆能将硼的浓 度降到 1×10-6以下,但Amberlite IRA-743树脂的吸硼性能明显地优于国产 564型树脂。 相似文献
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微量元素硼的环境意义 总被引:6,自引:0,他引:6
杨锐 《海洋地质与第四纪地质》1993,13(3):91-96
本文根据国内外大量实际资料的深入综合研究分析,认为微量元素硼可以作为确定古水体盐度的主要依据,亦可以作为判别沉积环境的一种方法。在实际应用时必须充分考虑各种影响因素,否则不一定具有普遍意义,有时结果会适得其反。 相似文献
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详细地研究了硼在水合氧化锆吸附剂上的吸附行为。研究结果表明,水合氧化锆的吸硼速率较快,2h可完全达平衡,且吸附可用Freundlich等温吸附线很好地拟合。被吸附的硼易被碱液洗脱,通过水合氧化锆上硼的“吸附-脱附循环”研究,表明该吸附剂的吸附性能好,再生能力强,循环使用寿命长,是一种很有价值的高效脱硼吸附剂。 相似文献
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Boron isotopic fractionation during seawater evaporation 总被引:6,自引:0,他引:6
Y.K. Xiao S.Z. Li H.Z. Wei A.D. Sun W.G. Liu W.J. Zhou Z.Q. Zhao C.Q. Liu G.H. Swihart 《Marine Chemistry》2007,103(3-4):382-392
Laboratory experiments were undertaken to investigate the behaviour of boron at the seawater–air interface during seawater evaporation. Seawaters adjusted to different pH values were heated to 27, 33 and 40 °C inside a quartz evaporator. The vapor was collected with a quartz condenser using a cold trap. A natural seawater–vapor process in quiet air conditions and excluding the sea-spray component was realized using this arrangement. The results indicate an enrichment of 11B in the condensate. This implies that in the natural environment, rainfall with δ11B values lower than that of seawater has been affected either by continental boron sources or by the boron extracted from seawater under airflow conditions. While the net flux of boron carried away from the ocean by air masses due to seawater evaporation is significant compared to other fractionation-associated processes removing boron from the ocean, the effect of isotopic fractionation as boron enters the vapor phase on the isotopic composition of boron in the ocean over time is small. 相似文献
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硼作为海水中的重要组分,其准确测定对海洋环境生物地球化学过程研究具有重要意义。海水中硼的常用测定方法具有前处理步骤繁琐、耗时长、样品易被污染、灵敏度低等缺点,不适于大批量海水样品的准确测定。为剔除海水高盐基体效应及干扰,本文运用电感耦合等离子体发射光谱法(ICP-OES),将海水样品进行稀释,采用标准加入法建立工作曲线,对海水中硼含量进行准确测定。正交实验显示,ICP-OES最佳工作条件为射频功率1400 W,雾化气流量0.7 L/min,观测高度14 mm,进样泵速1.5 m L/min。标准加入法标准曲线相关系数大于0.999,相对标准偏差为0.76%~1.27%,加标回收率为94.6%~101.8%,方法检出限为1.073μg/L。实际的海水样品分析表明,该方法可消除海水基体干扰,减少测定误差,并且前处理操作简单快速,化学试剂用量少,回收率高,精密度好,灵敏度高,可用于海水及其它高盐样品中硼含量的准确测定。 相似文献
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胶束增溶增敏分光光度法直接测定海水中的硼 总被引:4,自引:1,他引:3
首次以含量为15 % 的非离子型乳化剂OP100 胶束体系为介质进行硼的分光光度法测定研究,确定最佳实验条件( 最大吸收波长为555nm ,姜黄素用量为4mL,酸试剂用量为5mL,胶束用量为5mL,显色温度为50 ℃,显色时间为15min) ,改进了现有的姜黄法,此方法适用于海水中硼的水相直接分光光度测定。实验结果表明测定灵敏度显著增加(E= 1 .5 ×105) ,线性范围变宽(0 ~1.2μg/25mL) ,络合物稳定性好,稳定时间长达50h。 相似文献
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杭州湾海水中的硼和锶的研究 总被引:1,自引:0,他引:1
采用作者研究的OP- 乳化剂增敏姜黄素分光光度法测定海水中的溶解硼,用ICP- AES法测定海水中的溶解锶。发现在杭州湾海水盐度5 .563 ~26 .397 ,氯度3.022 ~14 .582 范围内,硼浓度为0 .68 ~3.24mg/kg,锶浓度为1 .29~5 .88mg/kg,B(mg/kg)/Cl 比值为0 .219~0 .245,平均值为0.232±0 .007 ,Sr(mg/kg)/Cl 比值范围为0.398 ~0.440 ,平均值为0.417 ±0.011 。结果表明,湾内海水中的硼和锶浓度与海水盐度或氯度均有很好的线性正相关关系,丰水期与枯水期水样数据关系相同,不因采水时间不同而变化。实验数据统计回归线与理论稀释线比较后表明,湾内海水中锶与硼均具有良好保守性质;湾内海水中的硼和锶主要来自湾外潮汐输入。湾东北沿岸海水高的B/Cl比值,暗示着此处有含硼工业废水排入湾内,认为B/Cl 比可作为近岸河口海水硼污染的一种指标。杭州湾海水中未检测到硼有机络合物。 相似文献