火焰原子发射光谱法测定碳化钛中微量钠

对火焰原子发射光谱法测定碳化钛中微量钠的条件进行了试验。样品用硝酸-氢氟酸溶解，在0．30mol／L硝酸介质中，以硝酸钾作消电离剂消除钠的电离干扰，饱和硼酸溶液络合试液中过量的氟离子。方法检出限为0．015μg／mL，样品加标回收率为97．6％-105．6％，方法的精密度（RSD，n=6）小于2．5％。     

干旱胁迫下钠复合肥对霸王(Zygophyllum xanthoxylum)根系生长的促进作用

霸王(Zygophyllum xanthoxylum)是荒漠区广为分布的一种多浆旱生植物。采用盆栽育苗的方法,初步评价了干旱胁迫下Na+对霸王根系生长的贡献,探讨了一种新型钠复合肥对霸王根系形态、生理学指标的影响。结果显示,钠复合肥能显著促进霸王根系的生长并提高其抗旱性:(1)正常浇水时,钠复合肥对霸王的促进作用主要体现在株高的增加和侧根的增长上,根系活力显著增强;(2)自然干旱15d后,钠复合肥使得霸王根系活跃吸收面积显著提高24%,促进主根的加粗和伸长以吸收更多的水分和矿质养分;(3)干旱胁迫下,钠复合肥处理使霸王根部Na+浓度保持较高水平,K+浓度下降42%。因此认为,干旱前钠复合肥显著促进了霸王侧根的生长和根系活力的提高,干旱后钠复合肥通过促进根系活跃吸收面积的扩大和主根的生长以提高霸王的抗旱性,其主要原因是根和叶中积累了较多的Na+、而非K+。     

Preparation,Characterization and Pharmacokinetics of Fluorescence Labeled Propylene Glycol Alginate Sodium Sulfate

A rapid and sensitive fluorescence labeling method was developed and validated for the microanalysis of a sulfated polysaccharide drug,namely propylene glycol alginate sodium sulfate （PSS）,in rat plasma.Fluorescein isothiocyanate （FITC） was selected to label PSS,and 1,6-diaminohexane was used to link PSS and FITC in order to prepare FITC-labeled PSS （F-PSS） through a reductive amination reaction.F-PSS was identified by UV-Vis,FT-IR and ^1H-NMR spectrum.The cell stability and cytotoxicity of F-PSS were tested in Madin-Darby canine kidney （MDCK） cells.The results indicated that the labeling efficiency of F-PSS was 0.522%±0.0248% and the absolute bioavailability was 8.39%.F-PSS was stable in MDCK cells without obvious cytotoxicity.The method was sensitive and reliable; it showed a good linearity,precision,recovery and stability.The FITC labeling method can be applied to investigating the absorption and metabolism of PSS and other polysaccharides in biological samples.     

Effect of sodium chloride and cadmium on the growth,oxidative stress and antioxidant enzyme activities of Zygosaccharomyces rouxii

Zygosaccharomyces rouxii is a salt-tolerant yeast species capable of removing cadmium(Cd) pollutant from aqueous solution. Presently, the physiological characteristics of Z. rouxii under the stress of sodium chloride(NaCl) and Cd are poorly understood. This study investigated the effects of NaCl and Cd on the growth, oxidative stress and antioxidant enzyme activities of Z. rouxii after stress treatment for 24 h. Results showed that NaCl or Cd alone negatively affected the growth of Z. rouxii, but the growth-inhibiting effect of Cd on Z. rouxii was reduced in the presence of NaCl. Flow cytometry assay showed that under Cd stress, NaCl significantly reduced the production of reactive oxygen species(ROS) and cell death of Z. rouxii compared with those in the absence of NaCl. The activities of superoxide dismutase(SOD), catalase(CAT), and peroxidase(POD) of Z. rouxii were significantly enhanced by 2%–6% NaCl, which likely contributed to the high salt tolerance of Z. rouxii. The POD activity was inhibited by 20 mg L-1Cd while the SOD and CAT activities were enhanced by 8 mg L-1 Cd and inhibited by 20 mg L-1 or 50 mg L-1 Cd. The inhibitory effect of high-level Cd on the antioxidant enzyme activities of Z. rouxii was counteracted by the combined use of NaCl, especially at 6%. This probably accounted for the decrease in Cd-induced ROS production and cell death of Z. rouxii after incubation with NaCl and Cd. Our work provided physiological clues as to the use of Z. rouxii as a biosorbent for Cd removal from seawater and liquid highly salty food.     

一起地热井粘附卡钻事故的处理

针对钻探工程施工中频繁发生的粘附卡钻事故,分析了发生粘卡事故的原因及相关因素,介绍了采用氢氧化钠水溶液作为解卡液的使用方法、措施和效果。     

电感耦合等离子体发射光谱法同时测定锡矿石中锡钨钼铜铅锌

锡矿石是难分解的矿物,共生与伴生元素多,其中的锡钨钼在单一盐酸溶液中易沉淀,准确测定锡矿石中的主次量元素一直是分析技术难点。本文以过氧化钠为熔剂,高温熔融样品,在酒石酸-盐酸-双氧水体系中进行酸化,选用该矿种中仅含有少量的钴作为内标,建立了电感耦合等离子体发射光谱同时测定锡矿石中锡钨钼铜铅锌的分析方法。方法线性范围为0.00~40.0 mg/L;方法检出限为锡10 mg/kg,钨30 mg/kg,钼3.3 mg/kg,铜12 mg/kg,铅15 mg/kg,锌40 mg/kg;方法精密度(n = 9)小于5.0%,实际样品的测定值与传统化学方法及国家标准方法的测定值吻合较好。本方法采用过氧化钠碱熔锡矿石,溶样彻底,并省去了氢氟酸挥发硅的蒸酸过程,节约了样品处理时间;采用酒石酸-双氧水-盐酸体系溶解熔融物,有利于溶液中的锡钨钼形成稳定的络合物,避免了单纯盐酸体系下产生钨酸、钼酸和锡酸沉淀导致测定结果偏低的问题。     

Groundwater quality in some Voltaian and Birimian aquifers in northern Ghana—application of mulitvariate statistical methods and geographic information systems

Abstract

Groundwater is a priceless resource in the economies of the rural populations in northern Ghana. A combination of multivariate statistical and spatial analytical techniques was applied to groundwater data from the Voltaian and Birimian aquifers in parts of northern Ghana. The objective was to classify the groundwater quality control parameters and determine whether the aquifers deliver groundwater of acceptable quality for domestic and commercial irrigation purposes. It was found that groundwater quality is dominated by the weathering of accessory minerals that are predominant in the Obosum and Oti beds of the Middle Voltaian in the north, and incongruent silicate mineral weathering ranks second among the major causes of variation. The two processes account for over 70% of the total variance in the hydrochemistry and interpolation maps generated for these two major factors are discussed. The mineral weathering and dissolution processes are less apparent within the Birimian aquifers. Four spatial groundwater types were distinguished by differences in EC and pH, which are high among the water types within the Obosum and Oti beds, and generally low within the Birimian aquifers. Mineral stability diagrams suggest that montmorillonite is the most stable clay mineral phase in the system, a significant finding in terms of cation exchange processes. This, in turn, has affected the irrigation quality of groundwater from the aquifers in the area. Our findings suggest that the Birimian aquifers are more suitable for irrigation, due to generally low salinities and sodicities, and those associated with the Obosum and Oti beds of the Middle Voltaian are less suitable.

Editor D. Koutsoyiannis; Associate editor Y. Guttman

Citation Yidana, S.M., Banoeng-Yakubo, B., Aliou, A.-S., and Akabzaa, T., 2012. Groundwater quality in some Voltaian and Birimian aquifers in northern Ghana—application of mulitvariate statistical methods and geographic information systems. Hydrological Sciences Journal, 57 (6), 1168–1183.     

海洋沉积物细菌群落结构对芘和苯甲酸钠胁迫的响应

应用分子生态学方法, 研究在不同芳香族化合物胁迫下海洋沉积物中细菌群落结构的演替 规律。在实验室建立驯化系统, 在海洋沉积物中分别添加芘和苯甲酸钠, 采用Illumina MiSeq 高通量 测序技术分析实验组和对照组细菌群落16S rRNA 基因V3-V4 可变区数量的组成及变化, 研究沉积物 中添加芘、苯甲酸钠后, 微生物群落多样性和群落结构的变化。实验结果表明: 芘、苯甲酸钠极大地 降低了海洋沉积物中菌群丰度和多样性; 在添加苯甲酸钠的实验组, 变形杆菌门中海杆菌属 (Marinobacter)、假海源菌属(Pseudidiomarina)的细菌显著富集; 在添加芘实验组中拟杆菌门中的 Balneola 属、碳酸噬胞菌属(Aequorivita)极大富集。初步分析了在海洋沉积物环境中不同多环芳烃胁迫 下细菌群落结构的演替特征, 实验结果为海洋环境中针对不同芳香烃的微生物修复提供理论依据。     

Optimized water vapor permeability of sodium alginate films using response surface methodology

The water vapor permeability （WVP） of films is important when developing pharmaceutical applications. Films are frequently used as coatings, and as such directly influence the quality of the medicine. The optimization of processing conditions for sodium alginate films was investigated using response surface methodology. Single-factor tests and Box-Behnken experimental design were employed. WVP was selected as the response variable, and the operating parameters for the single-factor tests were sodium alginate concentration, carboxymethyl cellulose （CMC） concentration and CaClz solution immersion time. The coefficient of determination （R2） was 0.97, indicating statistical significance. A minimal WVP of 0.389 8 g-mm/（m^2.h.kPa） was achieved under the optimum conditions. These were found to be a sodium alginate concentration, CMC concentration and CaCl2 solution immersion time at 8.04%, 0.13%, and 12 min, respectively. This provides a reference for potential applications in manufacturing film-coated hard capsule shells.     

α-萘乙酸钠对温室辣椒产量和内源激素水平的影响

以陇椒2号为试验材料,研究了α-萘乙酸钠对荒漠区日光温室辣椒产量和内源激素水平的影响。结果表明:叶面喷施35 mg·L-1的α-萘乙酸钠显著提高了辣椒生育后期的单果重,降低了辣椒不同生育阶段的落花落果率,改善了辣椒植株的营养条件,加速了辣椒根系和地上部分中后期的生长速率和干物质积累量,提高了辣椒不同生育阶段单株的产量。单果重和单株平均产量较对照分别提高15.76%和43.18%,落花落果率较对照降低19.77%。叶面喷施30～35 mg·L-1的α-萘乙酸钠显著降低了辣椒植株生长过程中叶片内源激素脱落酸（ABA）和吲哚乙酸（IAA）的含量,而且浓度越高,效果越明显;改变了辣椒叶片内源激素赤霉素（GA）和玉米素（ZR）的浓度和分布。辣椒植株的单株产量与叶片内源激素ZR含量正相关,与IAA和ABA的含量负相关,与GA相关性不显著。