稀土元素与中草药关系的探讨

根据有关文献资料,介绍了稀土元素在农业中,特别是中草药中的应用,探讨了稀土元素对中草药药效的影响。     

南黄海表层沉积物稀土元素分布与物源关系

对南黄海295个表层沉积物样品稀土元素的电感耦合等离子体质谱法分析,结果表明,南黄海表层沉积物稀土元素平均含量为188.39μg.g-1,稀土富集与重矿物有密切关系;稀土元素的球粒陨石配分模式均呈现Eu负异常,模式具负斜率,表明表层沉积物物质主要来源于大陆地壳。从稀土元素地球化学特征的区域变化来看,南黄海东部沉积物来源于朝鲜半岛,西部沉积物来源于黄河和长江物质输入,中部细粒沉积物主要与黄河及长江物质东南、东北扩散有关,东南部为朝鲜半岛及黄河、长江物质共同作用的结果。     

BTMPPA与HPMBP协同萃取稀土元素（Ⅲ）的研究

研究了二（２，４，４－三甲基戊基）膦酸（ＢＴＭＰＰＡ，ＨＬ）和１－苯基－３－甲基－４－苯甲酰基吡唑酮－５（ＨＰＭＢＰ，ＨＡ）的苯溶液在不同矿物酸介质中，对稀土元素（Ⅲ）的ＡＡ类协同革取。以Ｎｄ￣（３＋）、Ｙｂ￣（３＋）为例，研究了ＢＴＭＰＰＡ－ＨＰＭＢＰ苯溶液从ＨＮＯ＿３介质中协同萃取稀土元素（Ⅲ）的机理。用斜率法确定了协萃配合物组成为Ｎｄ（ＨＬ＿２）Ａ＿２、Ｙｂ（ＨＬ）２）＿２·Ａ·ＨＡ，计算了协萃平衡常数。     

稀土元素1∶6系列钼钴酸盐的合成与性质研究

首次合成了具有Ａｎｄｅｒｓｏｎ 结构的稀土元素钼钴杂多酸盐Ｌｎ［ＣｏＭｏ６Ｏ２４Ｈ６］·ｘＨ２Ｏ，（Ｌｎ ＝ Ｌａ，Ｃｅ，Ｐｒ，Ｎｄ，Ｇｄ，ｘ＝ ７ ～１０）．此类化合物属Ａｎｄｅｒｓｏｎ 结构的Ｂ型，其特点是杂原子与６ 个—ＯＨ 相连形成八面体．通过ＩＣＰ，ＩＲ，ＵＶ，ＴＧ－ ＤＳＣ，ＣＶ，ＸＲＤ 等方法对产物进行了表征     

以稀土元素为载体加强分析化学教学中思政教育的探索与实践*

在分析化学课堂上开展以稀土元素为载体的思政教育,对于解决我国在稀土高新技术开发领域“卡脖子”的难题具有重要意义。介绍了本校将稀土元素融入分析化学课程思政的建设思路,就如何发挥稀土元素的载体作用,实现全方位、全过程的思政建设目标进行了探讨,并给出了的具体实践案例。     

落叶松与白桦树中微量及稀土元素的ICP-MS检测方法研究

利用微波消解法处理植物灰分样品,讨论了混合酸组成、混酸配比、固液比和微波消解时间对样品制备结果的影响.优选微波消解方案:微波压力(MPa)0.5、1.0、1.5、2.0,消解时间(min)4、3、3、10的微波程序,混合酸体系HNO3-HCl-HF-HClO4(体积比为6 ∶ 2 ∶ 1 ∶ 1).在此条件下, 进行了方法准确度实验和测量结果重复性实验, 该方法经植物国家标准物质(GBW07603)验证,微量元素测试结果的相对误差为1.06% ～5.60%,相对标准偏差为0.87% ～5.25%;稀土元素测试结果的相对误差为1.82% ～10.2%,相对标准偏差为2.14% ～8.00%.应用电感耦合等离子体质谱法(ICP-MS)同时测定植物灰分中21种微量元素和15种稀土元素.结果表明, 微波消解法处理植物灰分样品, 具有快速、简便、节省试剂、消解完全等特点, 测定结果的准确度和精密度令人满意.     

稀土元素与3,4-二羟基苯甲醛缩邻氨基苯甲酸配合物的合成和表征

本文在三乙胺存在下合成了3,4-二羟基苯甲醛缩邻氨基苯甲酸(H_3L)与稀土元素的配合物。元素分析和摩尔电导值等确定其组成为[REL·nH_2O],(RE=La、Pr、Nd、Sm,n=3;RE=Gd、Dy、Ho、Yb、Y,n=4)。钆和钇配合物皆属重稀土组。磁化率、TG-DTA、IR和NMR等结果表明,配合物中不含硝酸根离子,负三价的配体离子以一种“扭曲”的形式与稀土离子配位。     

稀土元素的电分析化学研究 VIII.钆与邻苯二酚紫的配合吸附波

In certain supporting electrolytes, pyrocatechol violet (PV) may be reduced at single-sweep polarograph and a well-defined wave can be observed. The height of this wave decreases when Gd3+ is added into the solution and a sharp-peaked new wave is observed at more negative potentials. The height of this new wave is proportional to the concentration of gadolinium added. NH4Cl-(CH2)6N4 mixture (pH 5.5) was chosen as the suitable supporting electrolyte, in which the new wave of the Gd3+-PV complex is higher and the difference of peak potentials between PV and complex is larger. The linear relationship between wave height and concentration of Gd3+ holds in the range of 1X10-6-2X10-5 M. In this system other rare earth elements exhibit similar wave peaks. This wave has been proved to be an adsorptive-complex wave by several experiments.     

一类新的4-取代胂酸型变色酸偶氮多卤显色剂的合成及其与稀土元素显色反应的研究

本文研究了五个结构新颖的显色剂与稀土元素的显色反应。其中的二溴羧基偶氮氯肿(CAsA-DBK)与稀土元素反应具有对比度大、灵敏度高、选择性好等优点。在0.6mol/LHClO_4介质中,不加任何掩蔽剂条件下,只与铈组稀土显色,与钇组稀土几乎不显色,是一个较有特色的铈组稀土试剂。     

世界环境日活动与化学教育

世界环境日活动与化学学科紧密相关。介绍了世界环境日的由来及意义、历届世界环境日的主题、活动以及所涉及的化学知识,同时对从事化学教育教学的工作者提出了几点思考。     

Studies in the Field of Rare Earth Elements

The article describes developed and implemented technologies in the field of rare earth elements. Besides, new promising technologies for the realization of the work, carried out at the Department of Chemistry MEPhI in recent years, are represented.     

稀土元素分离检测技术新进展

对2003年以来稀土元素分离检测技术的新进展进行了评述，重点集中于各种新型分离技术、新型检测技术及其在稀土元素分析中的应用。对于离子液体、纳米材料、离子印迹聚合物等新型材料以及浊点萃取、膜萃取、毛细管电泳等新型技术在稀士元素分离中的应用进行了详细讨论，并对中子活化分析、等离子体原子发射光谱和等离子体质谱在稀土元素检测中的应用进行了综述，重点讨论了等离子体质谱技术的应用。在回顾稀土元素分离检测技术进展的同时，对其在未来几年的发展趋势进行了评述。     

Biohydrometallurgy for Rare Earth Elements Recovery from Industrial Wastes

Biohydrometallurgy recovers metals through microbially mediated processes and has been traditionally applied for the extraction of base metals from low-grade sulfidic ores. New investigations explore its potential for other types of critical resources, such as rare earth elements. In recent times, the interest in rare earth elements (REEs) is growing due to of their applications in novel technologies and green economy. The use of biohydrometallurgy for extracting resources from waste streams is also gaining attention to support innovative mining and promote a circular economy. The increase in wastes containing REEs turns them into a valuable alternative source. Most REE ores and industrial residues do not contain sulfides, and bioleaching processes use autotrophic or heterotrophic microorganisms to generate acids that dissolve the metals. This review gathers information towards the recycling of REE-bearing wastes (fluorescent lamp powder, spent cracking catalysts, e-wastes, etc.) using a more sustainable and environmentally friendly technology that reduces the impact on the environment.     

微量稀土元素的药效及保健作用

根据国内外微量稀土元素在医药方面应用的研究,介绍了稀土元素的一系列特殊的药效及保健作用。稀土元素可广泛用于治疗烧伤,炎症,皮肤病,血栓病等。     

Thermal Stability of 4-Chloro-3-Nitro- and 5-Chloro-2-Nitrobenzoates of Rare Earth Elements

The physico-chemical properties and thermal stabilities in air of rare earth element 4-chloro-3-nitrobenzoates and 5-chloro-2-nitrobenzoates were compared and the influence of the positions of the Cl and NO₂ substituents on their thermal stabilities was investigated. The complexes of both series are crystalline, hydrated or anhydrous salts with colours typical of Ln³⁺. The carboxylate group in these complexes is a bidentate, chelating ligand. The NO₂ group in the chloronitro complexes does not undergo isomerization. The thermal stabilities of the 4-chloro-3-nitrobenzoates of Y and the lanthanides were studied in the temperature range 273-1173 K, but those of the 5-chloro-2-nitrobenzoates of these elements were studied only at 273-523 K, because they decompose explosively above 523 K. The positions of the Cl and NO₂ substituents on the benzene ring influence the thermal properties of the complexes and their decomposition mechanisms. The different thermal stabilities of the complexes are connected with various inductive and mesomeric effects of the Cl and NO₂ substituents on the electron density in the benzene ring. This revised version was published online in July 2006 with corrections to the Cover Date.     

计算机差谱法测定混合稀土元素

报道了在自装光电二极管阵列电感耦合等离子体原子发射光谱仪上采用计算机差谱法进行混合稀土元素分析。该法能有效而简便地消除光谱干扰，结果准确可靠。     

稀土元素在植物中的分异研究进展

有关对稀土农用的理论和实践、天然和农业生态系统中稀土的地球化学行为及稀土的增产生理过程与毒理等方面已开展了大量研究,而对稀土进入植物体内的迁移过程、分布分异现象和机制缺乏必要的了解。稀土元素在植物中的分异研究有助于“示踪”稀土元素在土壤(溶液)-植物系统中的迁移路径,进而查明控制稀土元素迁移和积累的体外和体内敏感因素。本文结合近5年的研究工作,就近年来国内外有关稀土元素在植物中的分异现象、机制及其研究意义进行了综述,并展望了此方面的研究趋势,期望能为稀土以及重金属的生物有效性研究开辟一条新思路。     

Spectrochemical and Thermal Behaviour of the 5-chloro-2-nitrobenzoates of Rare Earth Elements

The conditions of the formation of yttrium and lanthanide 5-chloro-2-nitrobenzoates were studied and their quantitative composition and solubilities in water at 298 K were determined. They are anhydrous or hydrated complexes and their solubilities are of the order of 10-3 mol dm-3. The IR and X-ray spectra for the complexes were recorded. All complexes are crystalline compounds. Their thermal decomposition was studied. It was found that on heating above 523 K the complexes decompose explosively. Therefore their thermal decomposition was carried out in the temperature range 273-523 K. Hydrated complexes lose crystallization water molecules in one step. From the results it appeared that during dehydration process no transformation of nitro group to nitrito took place. Some of physico-chemical properties of rare earth element 5-chloro-2-nitrobenzoates were compared with 2-nitro- and 3-chlorobenzoates of those elements. This revised version was published online in July 2006 with corrections to the Cover Date.     

Thermal Stability of 4-chloro-2-nitro- and 4-chloro-3-nitrobenzoates of Rare Earth Elements: Influence of substituent positions

The physico-chemical properties and thermal stability in air of rare earth element 4-chloro-2-nitro- and 4-chloro-3-nitrobenzoates of the general formulae Ln(C₇H₃NO₄Cl)₃2H₂O were compared and the influence of the position of the Cl and NO₂ substituents on their thermal stabilities was investigated. The complexes of both series are crystalline, hydrated salts with colours typical of Ln³⁺. The carboxylate group in these complexes is a bidentate, chelating ligand. The NO₂ group in the chloronitro complexes does not undergo isomerization. The thermal stabilities of the 4-chloro-3-nitrobenzoates of rare earth elements were studied in the temperature range 293–1173 K, but those of 4-chloro-2-nitrobenzoates of those elements were studied only at 293–523 K because they decompose explosively above 523 K. The positions of the Cl and NO₂ substituents on the benzene ring influence the thermal properties of the complexes and their decomposition mechanisms. The different thermal stabilities of the complexes are connected with various inductive and mesomeric effects of the Cl and NO₂ substituents on the electron density in benzene ring.This revised version was published online in November 2005 with corrections to the Cover Date.