Effect of Al Addition on Grain Refinement and Phase Transformation of the Mg-Gd-Y-Zn-Mn Alloy Containing LPSO Phase

The effect of 0–1.0 at.% Al additions on grain refinement and phase transformation of the Mg-2.0Gd-1.2Y-0.5Zn-0.2Mn (at.%) alloy containing a long period stacking ordered (LPSO) phase was investigated in this work. The addition of Al promoted the formation of the Al₂RE phase in the Mg-2.0Gd-1.2Y-0.5Zn-0.2Mn (at.%) alloy, and the dominant secondary phases in the as-cast Mg-2.0Gd-1.2Y-0.5Zn-0.2Mn-1.0Al (at.%) alloy were the Mg₃RE phase, LPSO phase, and Al₂RE phase. With increased Al addition, the area fraction of the Al₂RE phase increased monotonously, while the area fraction of LPSO phase and Mg₃RE phase decreased gradually. The orientation relationship between the Al₂RE phase and the α-Mg matrix was determined to be <112>_Al2RE//<112¯0>_α-Mg, {101}_Al2RE//{101¯0}_α-Mg, which was not affected by Zn and Mn concentrations in the Al₂RE phase. Since the Al₂RE particles with a size more than 6 μm located at the center of grains could act as nucleants for α-Mg grains, the average grain size of the as-cast alloys decreased from 276 μm to 49 μm after 1.0% Al addition. The effect of the Al addition on the grain refinement of the Mg-2.0Gd-1.2Y-0.5Zn-0.2Mn alloy was comparable to that of the Zr refined counterpart.     

深圳近岸海域海洋动物稀土元素组成特征及配分模式研究

目的建立定量测定深圳近岸海域海洋动物稀土元素(REE)的方法,并对REE组成特征以及配分模式进行分析研究。方法在深圳近岸海域采集60份海洋动物样本,采用电感耦合等离子体质谱法(ICP-MS)测定钇、镧、铈、镨、钕、钐、铕、钆、铽、镝、铒、钬、铥、镱、镥等15种稀土元素,并选择国家一级标准物质茶叶(GBW10016)进行定量分析的质量控制。结果软体动物、藤壶、鱼类及虾类的REE平均测定值分别为(2.66±2.28)、(4.69±1.32)、(0.03±0.03)和(0.07±0.02)μg/g;所测海洋动物的稀土配分特征总体上都表现为轻稀土元素的富集。结论(1)球粒陨石标准化处理表明,藤壶、软体动物和虾类与南海北部陆坡海洋沉积物、香港土壤以及中国大陆土壤稀土平均值配分模式较接近,而鱼类的则有所差异;(2)双壳类软体动物由于体内REE总量较高而存在食用安全风险;(3)由REE富集能力、与海洋沉积物相似的REE配分模式以及附着生长特性等方面的特征显示,藤壶及牡蛎是较好的海洋环境REE指示动物。     

Methanol Adsorption and Reaction on Samaria Thin Films on Pt(111)

We investigated the adsorption and reaction of methanol on continuous and discontinuous films of samarium oxide (SmO_x) grown on Pt(111) in ultrahigh vacuum. The methanol decomposition was studied by temperature programmed desorption (TPD) and infrared reflection absorption spectroscopy (IRRAS), while structural changes of the oxide surface were monitored by low-energy electron diffraction (LEED). Methanol dehydrogenates to adsorbed methoxy species on both the continuous and discontinuous SmO_x films, eventually leading to the desorption of CO and H₂ which desorbs at temperatures in the range 400–600 K. Small quantities of CO₂ are also detected mainly on as-prepared Sm₂O₃ thin films, but the production of CO₂ is limited during repeated TPD runs. The discontinuous film exhibits the highest reactivity compared to the continuous film and the Pt(111) substrate. The reactivity of methanol on reduced and reoxidized films was also investigated, revealing how SmO_x structures influence the chemical behavior. Over repeated TPD experiments, a SmO_x structural/chemical equilibrium condition is found which can be approached either from oxidized or reduced films. We also observed hydrogen absence in TPD which indicates that hydrogen is stored either in SmO_x films or as OH groups on the SmO_x surfaces.     

谈CT不良地线引起的故障及地线的制作方法

CT的地线引起的故障虽然不多,但维修停机时间长,造成的损失严重.本文通过对 CT地线不良引起的典型故障的维修,分析总结了 CT地线故障的特点.针对地线的制作提出了改进的方法.     

培土生金法治疗抗结核药物所致肝损害43例述要

目的 :观察培土生金法治疗抗结核药所致轻、中度肝损害的疗效。方法 :将抗结核药物所致肝损害病者 85例分为 2组 ,治疗组 43例不停用抗结核药而加用中药 ,对照组 42例不停用抗结核药但不用中药。两组均进行基础治疗 (服肌苷、维生素 B1)。结果 :两组总有效率分别为 88%或 67% ,有非常显著性差异 ( P<0 .0 1)。两组治疗前后 AL T、AST、TB指标也有明显变化 ( P<0 .0 1,P<0 .0 5)。结论 :培土生金法治疗抗结核药所致的轻、中度损害有明显效果。     

若干中草药中25种元素在不同浸取液中的分布

目的 :通过测定不同浸取液中 2 5种元素含量 ,探讨这些元素在中草药中的存在形态。方法 :对同一产地的 5种不同中草药密蒙花Buddleja officinalis、白鲜皮Dictamnus dasycarpus、肉豆蔻Myristica fragrans、合欢Albizia julibrissin、旋覆花Inula japonica进行水提、二氯甲烷浸取、残渣消化 ,分别得到水溶相、脂溶相、不溶相 ;参照药典方法对我国 9个不同产地的商陆Phytolacca acinosa进行了 0 %乙醇、50%乙醇、75%乙醇和 95%乙醇的浸取处理 ;使用ICP-MS(电感耦合等离子体质谱仪 )测定上述三相及各个乙醇浸取液中铍、镉、铈、铬、铜、镝、铕、铒、钆、锗、钬、镧、镥、钼、钕、铅、镨、钐、锶、铽、铊、铥、钇、镱和锌共 25种元素的含量。结果 :实验表明 ,用不同溶剂浸取中草药时微量元素的浸取率有较大差异 ,并以有机态与无机态形式共存。在优化实验条件下 ,ICP-MS能够同时测定中草药中的25种元素 ,其方法检出限为 0.003～0.71μg·L^-1。中草药中元素的加标回收率为 88%～119% ,相对标准偏差为1.7%～13.3%。结论 :上述结果对于在中成药生产过程中尽可能地浸取人体必须元素、除去有毒元素、促进中药出口具有一定的指导意义。     

稀土与肿瘤关系的探讨

为了探讨稀土与肿瘤的关系，我国按卫生部抗肿瘤药物体内药效实验规程，对混合轻稀土进行了体内抑瘤实验，结果在３２ｍｇ／ｋｇ剂量下其抑瘤率对Ｓ１８０肉瘤为３９．８７％，对Ｌｅｗｉｓ肺癌为３６．８２％有明显的抑瘤作用，超过了有效药物抑瘤标准（３０％）；体外抑瘤实验用ＭＴＴ法、３Ｈ－ＴｄＲ掺入法入及细胞倍增时间的测定结果，均证明对人体羊膜细胞有生长作用，而对人白血病瘤细胞Ｋ５６２有抑制作用。抗诱变实验结果表     

The Electrical and Thermal Transport Properties of La-Doped SrTiO3 with Sc2O3 Composite

Donor-doped strontium titanate (SrTiO₃) is one of the most promising n-type oxide thermoelectric materials. Routine doping of La at Sr site can change the charge scattering mechanism, and meanwhile can significantly increase the power factor in the temperature range of 423–773 K. In addition, the introduction of Sc partially substitutes Sr, thus further increasing the electron concentration and optimizing the electrical transport properties. Moreover, the excess Sc in the form of Sc₂O₃ composite suppresses multifrequency phonon transport, leading to low thermal conductivity of κ = 3.78 W·m⁻¹·K⁻¹ at 773 K for sample Sr_0.88La_0.06Sc_0.06TiO₃ with the highest doping content. Thus, the thermoelectric performance of SrTiO₃ can be significantly enhanced by synergistic optimization of electrical transport and thermal transport properties via cation doping and composite engineering.     

法天则地的中医现象学

文章认为基于中国传统文化法象思维模式建构的中医理论具有丰富的法之象和法于象的生动演绎和具体应用,认为法天则地是生物和人类进化适者生存的结果,取类比象是中医实现法天则地目的的现象学方法.通过东西方跨文化的比较发现,近现代西方科学的许多发现亦得益于类比方法,中医法象之说虽然具有时代的局限性,缺乏将复杂的事物进行简单化处理后...     

论培土生金法在肺癌治疗中的地位和作用

肺癌晚期常见脾虚证候,对肺癌的预后有重要的影响。培土生金法涵盖了重在脾阳的健脾法和重在脾阴的滋脾法,以培土生金为主的治法可提高患者生存质量、延长生存期,可作为晚期肺癌的长期治疗措施。