Separation and Precise Measurement of Lithium Isotopes in Three Reference Materials Using Multi Collector‐Inductively Coupled Plasma Mass Spectrometry

Lithium separation technique for three reference materials has been established together with precise determination of lithium isotope using a Neptune multi collector-inductively coupled plasma mass spectrometry (MC-ICP-MS). The solutions of lithium element standard reference materials, potassium, calcium, sodium, magnesium and iron single element, were used to evaluate analytical methods applied. Three separate stages of ion-exchange chromatography were carried out using organic cation-exchange resin (AG 50W-X8). Lithium was enriched for the three stages using different eluants, which are 2.8 M HCl, 0.15 M HCl and 0.5 M HCl in 30% ethanol, respectively. The columns for the first and second stages are made of polypropylene, and those for the third stage are made of quartz. Total reagent volume for the entire chemical process was 35 mL for three reference materials. The recovery yielded for the three stages is 98.9–101.2% with an average of 100.0%, 97.6–101.9% with an average of 99.9%, and 99.8–103.3% with an average of 100.6%, respectively. The precision of this technique is conservatively estimated to be ±0.72–1.04‰ (2σ population), which is similar to the precision obtained by different authors in different laboratories with MC-ICP-MS. The δ7Li values (7Li/6Li relative to the IRMM-016 standard) determined for andesite (AGV-2) and basalt (BHVO-2) are 5.68‰ (n=18), 4.33‰ (n=18), respectively. The δ7Li value (7Li/6Li relative to the L-SVEC standard) determined for IRMM-016 is –0.01‰ (n=15). All these analytical results are in good agreement with those previously reported. In addition, the results for the same kinds of samples analyzed at the MLR Key Laboratory of Metallogeny and Mineral Assessment, Institute of Mineral Resources, Chinese Academy of Geological Sciences, are consistent with those obtained at the Plasma Laboratory, University of Maryland, within analytical uncertainty. According to these experiment results, it is concluded that this proposed procedure is a suitable method for determining the lithium isotopic composition of natural samples.     

中药治疗便秘型肠易激综合征SD大鼠的实验研究

目的：研究柴胡疏肝散合济川煎对肝郁气滞合并阳虚型便秘型肠易激综合征（IBS-C）模型大鼠的治疗效果及作用机制。方法：将56只SPF级雄性SD大鼠随机分为正常组（8只）和模型组（48只）,模型组采用冰水灌胃、限制饮水结合慢性束缚应激的方法制备肝郁气滞合并阳虚型IBS-C大鼠模型。将造模成功的大鼠随机分为模型对照组、复方聚乙二醇电解质散（PEG-EP)组、黛力新组及中药低、中、高剂量组,每组各8只。各组进行药物干预14 d。观察指标包括大鼠一般状态、糖水偏好率、旷场实验评分、内脏敏感性、小肠推进率、结肠黏膜HE染色及血清5-羟色胺( 5-HT) 、生长抑素(SS) 、血管活性肠肽（VIP）含量测定。结果：与模型对照组相比,柴胡疏肝散合济川煎能使模型大鼠的粪便粒数、粪便含水量、Bristol 分值、内脏敏感性、旷场试验评分、糖水偏好百分比、小肠推进率增加(P<0.01 或P<0.05),血清5-HT、SS含量降低(P<0.05),血清VIP含量升高（P<0.05）;与PEG-EP组、黛力新组相比,中药高剂量组大鼠血清5-HT、SS均降低(P<0.05),VIP水平升高(P<0.05)。结论：大鼠肝郁气滞合并阳虚型IBS-C模型制备成功,柴胡疏肝散合济川煎可改善模型大鼠肝郁和便秘症状,其作用机制可能与降低大鼠血清5-HT、SS含量和升高大鼠血清VIP含量有关。     

Magnetic Fabric Study of Late Holocene Sediments in Huangqihai Lake,Inner Mongolia and its Sedimentary Significance

The detailed magnetic susceptibility anisotropy study on the sediments of two sections, which are located in the lake-center and the lakeshore of the Huangqihai Lake,Inner Mongolia, revealed their hydrodynamics and sedimentary environment changes in the recent 2000 years.The results show that the sediments of two sections both display normal depositional magnetic fabrics,of which the minimum susceptibility axes（K₃） are oriented perpendicular to the bedding plane and the maximum magnetic susceptibility axes（K₁） lie parallel with the bedding plane.In addition,the lakeshore presents higher magnetic anisotropy degree（P）,magnetic foliation（F） and current factor （F_s） than the lake-center,showing that the lakeshore has higher flow velocity.For the west Huangqihai Lake（HQW） section in the lake-center,the magnetic matrix grain degree（Q） and the inclination of the minimum susceptibility axes sharply increased and decreased,respectively,at a depth of about 10 cm,24 cm,45 cm and 74 cm,which indicate abnormal depositional events with strong kinetic energy.Through comparative analysis,the HQW section can be divided into three stages from top to bottom.The upper stage was a stable depositional environment with strong hydrodynamic energy and low water level,which shows relatively higher F_s value and the Q value varies similarly with P and F.The middle stage was a stable depositional environment with high water level and low hydrodynamic energy,intermitted with high-energy abnormal events,which shows relatively lower F_s and the Q value was negatively correlated with P and F.The lower stage was an unstable depositional environment with low hydrodynamic energy and high water level,which shows relatively lower P,F,and F_s value.     

桂西北喀斯特区常绿落叶阔叶混交林种群种间联结性与相关性

通过AC测定、X~2检验、Pearson相关检验和Spearman秩相关检验多种指标,分别测定广西木论国家自然保护区9个乔木优势种群在6种不同尺度取样面积下的种间联结性和相关性.结果表明:在中亚热带石灰岩常绿落叶阔叶混交林内,种间联结性测定的取样面积以64-100 m~2为宜,而在9×9 m~2取样中最能体现优势种群的种问联结性及整个群落的特征;9种优势种组成的36对种对中,有15对存在显著或极显著关联,其中正关联12对,占所有显著或极显著关联对数的80%,占所有种对数的33.33%;负关联3对,占所有关联对数的20%,占所有种对数的8.33%.     

澳大利亚兰杰一号铀矿之生命周期：地质、资源、生产与修复

兰杰一号铀矿及其所属的鳄鱼河铀矿田产于北澳太古宙克拉通内古元古代裂谷背景下发展起来的松溪造山带,矿体产于新太古代—古元古代结晶-变质基底/晚古元古代—中元古代康博尔吉红层建造不整合界面之下,铀矿化分3个时代,U_1为1720～1680Ma,U_2为1420～1040Ma,U_3为474±6Ma,U1是主矿化时代。该矿床于1969年后期通过航空放射性测量被发现,1970’s经勘探圈定了No.1和No.3两个铀矿体,总计资源储量124681t@0.23%U_3O_8。1980年10月正式露采,至2018年12月,总计生产了128739t U_3O_8。1985财年开始,ERA(澳大利亚能源资源有限责任公司)向世界核能市场共计销售了产于兰杰铀矿的119882t U_3O_8。2009年,发现了No.3深部矿,探明资源储量为43857t@0.22%U_3O_8,这部分资源将以地下开采方式利用。预计到2026年,采区地貌景观和生态环境将得到恢复。进一步讨论了澳北元古宙不整合面型铀矿找矿的方向,持续稳定的铀矿开采与生产的意义,以及投资澳大利亚铀矿业需要注意的政治与法律问题。这些内容可以为国内矿业企业及地勘单位合理部署澳洲铀矿勘查与开发提供参考。     

锂同位素在伟晶岩矿床成因研究中的应用

稀有金属矿产对现代工业和科技的发展极其重要,伟晶岩矿床作为稀有金属的主要来源,其成因与成矿作用有待深入研究,普遍争论的成因模式包括:花岗岩结晶分异、地壳部分熔融以及岩浆液态不混溶。研究表明地壳深熔过程中锂同位素不发生有意义的分馏,因此在解决花岗岩和伟晶岩的岩浆源区性质方面提供了强有力的证据。文章主要从花岗伟晶岩的成因、锂同位素分馏机制以及锂同位素在伟晶岩矿床中的应用三个方面系统综述了国内外近年来取得的一些研究进展。国内外学者以锂同位素分馏机制详细论述了花岗伟晶岩的Li同位素组成,认为伟晶岩矿床的成因主要为花岗岩结晶分异或地壳部分熔融。但是锂同位素应用于伟晶岩矿床成因方面的研究还不够成熟,需要开展更多的工作。     

吉林夹皮沟金矿带电、磁场与流体中成矿元素运移、富集效应

本文以吉林夹皮沟金矿带为例,通过板块碰撞或旋转所产生的磁斥力和电场来探讨流体中成矿元素运移和富集机制。基于块体转动与岩石剩磁磁斥力的产生,岩石电、磁场的形成和阴 阳离子相向漂移的地质证据及成矿流体与磁感应矢量、电导率间对应关系的讨论,表明:1)成矿元素的富集发生于新旧电、磁场交替变化过程中;2)岩石电场正、负极控制阴、阳离子作相向漂移运动,是流体中成矿元素运移、富集的主要控制因素之一;3)深大断裂界面间的磁斥力是Au、Ag、Cu、Pb和Zn等有色多金属抗磁性元素成矿的有利场所。     

科学数据共享领域的政策规范和法律规范

科学数据共享活动中有数据产生与汇交、数据保管与使用、数据共享评估与监督、数据共享保障四个领域,针对性四个领域出台不同的政策规范和建立不同的法律制度,规范科学数据共享领域的社会关系。     

日本刺沙蚕摄食沉积物的实验研究

日本刺沙蚕为典型的沉积食性底栖动物,通过大量吞食沉积物来获得能量,以维持自身的营养需求。作者于１９９６年１０月在山东省丁字湾北部泥滩潮间带采集日本刺沙蚕,利用肠道内含物分析方法测定了日本刺沙蚕对自然沉积物的摄食率,其结果为５．７１±２．７６ｍｇ．ｍｇ－１．ｄ－１,并估算出日本刺沙蚕饱食沉积物所需时间约为６．５８ｈ。日本刺沙蚕在摄食沉积物时偏向于选择较大的颗粒,这与最适觅食模型的结论相反。这一结果可用底栖生物对其栖居环境适应方式的特殊性来解释。     

剔除拟合法在ST盆地地震资料处理中的应用

利用一系列处理方法,特别是利用剔除拟合法替代水平叠加技术,可获得高分辨率、高保真度和高信噪比的地震资料。对该资料解释后认为具有以下特点：（１） 能提高地震资料的分辨率和信噪比;（２） 为地震资料的反演处理提供较理想的基础资料;（３） 能提高储层预测的精度;（４） 能提供合理的角道差三维数据体。