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《成都理工学院学报》2002,29(4):453-457
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本文报导了在多聚磷酸作用下,0,0’-邻苯二酚二乙酸同三聚甲醛缩聚生成具有对钾离子吸着作用的树脂的反应。探讨了摩尔配比、反应温度和反应时间等影响树脂性能的因素。提出了合成0,0’-邻苯二酚二乙酸—甲醛树脂的最宜条件: CH_2O:CDAH_2=1:4(摩尔); (CH_2O+CDAH_2):PPA=1:4(重量); 温度=120—130℃;时间=1小时。树脂产率为84—91％。树脂在380PPm氯化钾水溶液中(相当于海水中的钾离子浓度)对钾离子的吸着容量是28—30毫克钾离子/克(干树脂)[动态法]。富集因数是73—78。 相似文献
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斜发沸石对钾离子的吸附/解吸动力学研究 总被引：1，自引：0，他引：1
以KCl为钾源、新疆某地所产斜发沸石为吸附剂,研究斜发沸石对K+的动力吸附与解吸效果,并探讨吸附时间、K+初始浓度与吸附量的关系。用pH=5的HCl溶液和(Ca2++Mg2+)浓度/(mmol.L-1)为1.6,3.2,6.4,12.8,19.2,25.6的混合溶液对饱和吸附了K+的斜发沸石进行解吸,实验结果表明:沸石对K+的吸附在4min能达到最大吸附率的96%,30min内达到平衡。Langmuir吸附等温式能对吸附曲线进行很好的描述。单位质量沸石对K+的最大吸附量为44.53×10-3,以阳离子交换吸附为主。pH=5的HCl溶液对K+的解吸量最小,随解吸溶液中(Ca2++Mg2+)浓度增加,解吸滞后系数减小,解吸速率远小于吸附速率。解吸量的自然对数与解吸时间的自然对数呈现明显的线性关系,用指数方程对(Ca2++Mg2+)浓度为25.6mmol/L的解吸曲线进行拟合,R=0.998,拟合方程为qt=3.890t0.210。理论上将吸附的K+全部解吸出来需要74.4d。 相似文献
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The effects of environmental Na /K ratio on the gill ion-transport enzyme activity,plasma osmolality and growth ofCynoglossus semi/aevis juveniles were investigated.The results showed that,plasma osmolality was similar among flounder adaptedto different Na /K ratios of saline groundwaters (P>0.05),while the growth,gill Na ,K -ATPase and HCO,3'--ATPase activities wereaffected by Na /K ratio significantly (P<0.05).The gill Na ,K -ATPase activity reached its maximum on day 3,then decreasedgradually from day 3 to day 9 and remained constant from day 9 to day 15.The peak values of gill Na ,K -ATPase activity weredetected on day 3 for all Na /K ratios of saline groundwaters,then the enzyme activities descended,and on day 9 the enzyme activi-ties achieved steady state,and the gill HCO,3--ATPase activity increased rapidly and achieved steady state after one day.Duringsteady state,the gill Na ,K -ATPase and HCO,3--ATPase activity of Na /K ratios 20 and 40 treatments were significantly higherthan those in the control group (Na /K ratio 27.5),while there were no significant differences between the Na /K ratio 30 treatmentand the control group; the gill Na ,K -ATPase activity of Na /K ratio 20 and 40 treatments were significantly higher than that forratio 30 treatment,but there were no significant differences of gill HCO3-ATPase activity among these treatments.At the end of the15-day experiment,the weight gain (%) and specific growth rate (SGR) of flounders maintained in seawater were significantly higherthan those in groundwaters; significant differences also occurred among the treatments; Na /K ratio 30 treatment had the highestvalues (33.7% and 1.94 respectively),which were significantly higher than those under Na /K ratios 20 and 40 treatments.There-fore,for the saline groundwater used in this experiment,it is suggested that the Na /K ratio be adjusted to approximately 30,I.e.,asclose to that of natural seawater as possible in the culture of flounder. 相似文献
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我们曾报道过以对钾离子有着良好选择吸着性能的O，O’-邻苯二酚二乙酸(简称CDAH2)为单体，在多聚磷酸存在下，同三聚甲醛反应，合成CDAH2-甲醛树脂的工作，并确定了该树脂在相当于海水中钾离子浓度的氯化钾溶液中的钾离子吸着性能。 相似文献
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Penguin and skua in the maritime Antarctic have high salt loadings in the body due to almost exclusive diet consumption of marine invertebrates. However, the storage and turnover of sodium and potassium in these animals are poorly investigated. Here we determined the concentration and microscopic distribution of the two elements in the bones of penguin and skua. The average concentrations of sodium and potassium in penguin bone were comparable with that in skua bone (0.18% and 0.82% for penguin bone; 0.19% and 0.76% for skua bone in dry weight). The ratios of sodium to calcium and potassium to calcium (0.0330 and 0.0075 for penguin, 0.0335 and 0.0082 for skua in average by weight) were somewhat higher than the reported ratios for terrestrial animals, indicating these marine animals' bone enrichment of salt. The ratios of sodium to potassium in average by weight were 6.75 and 4.65 for penguin and skua, respectively. This value is much lower compared with the bulk sea water ratio of about 27.0, implying that potassium is favorable to reside in the bone rather than sodium. Both sodium and potassium were found to significant correlation with the content of organic materials in bone based upon the intensity of native signal determined by electron paramagnetic resonance (EPR). It was estimated that almost all of potassium is kept within the organic phases, while about 30% of sodium is stored in organic phases and the other 70% within mineral phase. The microscopic distributions of potassium in the cross-section and/or surface were revealed by synchrotron radiation X-ray fluorescence (SR-XRF) technique. The ratio of potassium to calcium based upon the SR-XRF intensity counter varied considerably from the surface to the interior, and on the surface the highest concentration of potassium was observed in the middle section with decreasing amounts toward the edge. This indirectly documented that exchange of potassium between fluid and bone organic phase maybe occur. 相似文献
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引言 从海水中直接提取钾盐是海水资源化学的重要研究课题之一。海水中的钾以K2O估算，总储量达580万亿吨，如此丰富的钾资源取之不尽用之不竭，引起了人们对海水提钾的兴趣。但是，海水中钾的浓度仅约380毫克／升左右，且有将近30倍的钠离子共存，这就使用较低的成本从海水中提取钾盐成为难题。 相似文献
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首次报道了一种冠合型醇酸树脂的分子设计、合成方法及其对低浓度溶液和海水体系中钾离子的富集性能。基于近年来发展的＂主－客体化学＂（ＨｏｓｔＧｕｅｓｔＣｈｅｍｉｓｔｒｙ）等理论概念构思，设计并合成出一种冠合型聚双内酯类的新高分子钾离子富集剂，即均苯四酸－二甘醇聚大环醚双内酯（Ｐｏｌｙｍａｃｒｏｃｙｃｙｃｌｉｃｅｔｈｅｒｂｉｓｌａｃｔｏｎｅｏｆｄｉｅｔｈｌｅｎｅｇｌｙｃｏｌｐｙｒｏｍｙｌｌｉｔｉｃａｃｉｄ，以下简称ＰＢＬ树脂），产率几为定量，为９７．４％左右。笔者研究了这种热固性树脂对低浓度钾盐溶液、莱州湾海滨地下卤水和天然海水中钾离子的富集行为，实验结果表明ＰＢＬ树脂可适用于天然海水及莱州湾地下卤水等复杂体系中低浓度钾离子的富集分离，富集容量可分别达到２２．５×１０（－３）和３６．５×１０（－３）。初步探讨了ＰＢＬ树脂的捕钾机理，并对富氧大环高分子对钾离子选择性络合的孔径匹配理论提出了新的见解。 相似文献