Modeling and Characterization of Complex Concentrated Alloys with Reduced Content of Critical Raw Materials

The continuous development of society has increased the demand for critical raw materials (CRMs) by using them in different industrial applications. Since 2010, the European Commission has compiled a list of CRMs and potential consumption scenarios with significant economic and environmental impacts. Various efforts were made to reduce or replace the CRM content used in the obtaining process of high-performance materials. Complex concentrated alloys (CCAs) are an innovative solution due to their multitude of attractive characteristics, which make them suitable to be used in a wide range of industrial applications. In order to demonstrate their efficiency in use, materials should have improved recyclability, good mechanical or biocompatible properties, and/or oxidation resistance, according to their destination. In order to predict the formation of solid solutions in CCAs and provide the optimal compositions, thermodynamic and kinetic simulations were performed. The selected compositions were formed in an induction furnace and then structurally characterized with different techniques. The empirical results indicate that the obtained CCAs are suitable to be used in advanced applications, providing original contributions, both in terms of scientific and technological fields, which can open new perspectives for the selection, design, and development of new materials with reduced CRM contents.     

Compatibility Tests between Three Commercially Available Organic PCMs and Metals Typically Used in Fin-and-Tube Heat Exchangers

Energy storage is one of the most effective ways to increase energy savings and efficiency of heating and air conditioning systems. Phase change materials (PCMs) are increasingly used in latent heat thermal energy storage (LHTES) systems to increase their capacity. In such systems, costs are a very important factor of viability so the typical heat transfer elements like fin-and-tube heat exchangers are used to construct the LHTES. The problem of this approach is a possibility of corrosion of metals in contact with PCM that shortens the life cycle of LHTES. Therefore, the main objective of this work is an experimental study of the compatibility of metals typically used in fin-and-tube heat exchangers (copper and aluminum) with three commercially available organic PCMs (RT15, RT18HC, and RT22HC). Compatibility of PCMs with copper and aluminum was tested for a period of approximately two months, during which a total of 35 heating and cooling cycles were carried out, each with a complete phase transition of the tested materials. In the course of the tests it was assessed whether the PCM caused corrosion of the tested metals. The evaluation was based on the gravimetric method, calculation of corrosion rate, and visual observations and measurements of the features on the metal sample’s surface using optical microscope. It was determined that RT15, RT18 HC, and RT22 HC show low corrosion rates for aluminum and copper samples. The visual tests indicate that there was no change in the PCM solutions during the tests, only a sediment was observed for the samples with the combination of copper and aluminum. Microscopic examination of the surface of the samples did not show any significant surface changes, except for the aluminum samples, on the surface of which local microdefects were observed. It follows from the present results that copper and aluminum can be used to design the heat transfer surface in contact with the chosen PCMs.     

新型骨组织工程支架材料生物相容性的体内研究

目的通过比较2种新型骨组织工程支架材料即聚消旋乳酸/聚乳酸－聚乙二醇－聚乳酸/磷酸三钙（A）、聚消旋乳酸/聚乳酸－聚乙二醇－聚乳酸（B）与对照组聚消旋乳酸（C）修复兔下颌骨缺损的效果,探讨新型可吸收性生物支架材料体内埋植的生物相容性。方法24只成年新西兰大白兔按取材时间随机分为4组。双侧下颌骨下缘形成15 mm×6 mm全层骨质缺损, 每一缺损作为一个实验单位。每组内按完全随机化设计植入实验材料和对照材料。术后2、4、8、12周取材行大体标本、X线、组织学观察及计算机图像分析。结果复合支架材料A、B与聚消旋乳酸相比,复合支架B生物相容性好,同期成骨量最大;复合支架A出现明显的异物肉芽肿反应。结论新型复合支架材料B生物相容性好,效果优于聚消旋乳酸,有可能成为一种较理想的支架材料。复合支架A不适宜作为骨组织工程生物支架材料。     

国家级精品课程《护理学基本技术》立体化教材的建设与体会

目的结合现代化的教学手段,建设《护理学基本技术》立体化教材,实现优质教学资源共享。方法根据教学大纲和培养目标,优化教学资源,在护理专业学生《护理学基本技术》教学中应用立体化教材。结果《护理学基本技术》的立体化教材被广泛使用,并得到好评,提高了教学效果和师生双方的满意度（P〈0．05）。结论个体化教材有助于教学资源的整合、教育要素配黄途径的优化及护生核心能力的培养,同时也满足了精品课程远程教育的需要。     

归纳性图表素材库在康复医学教育中的运用

归纳性图表素材库是为完善多媒体教学素材库而细化出的一个教学素材子库,具有简洁、清晰、重点突出等特点,可提高授课效率和教学质量。本文结合康复医学教育的具体情况,探讨了在课堂教学上侧重应用归纳性图表素材库的优势。     

中药复方中物质基础的增效因素

本文重点从中药复方中发生的化学成分间的变化及药效的关系,提出了复方中一些化学成分的变化是增效因素的观点,由于这方面的研究报道尚不多,研究工作还较粗浅,仅就已发现的一些物质基础化通过实例,暂归纳为６个方面的增效因素,（１）化学成分间的水解转化,促使某些成分发生量或质的变化,（２）某些化学成分促使提高有效成分的溶出率,（３）某些化学成分的变化减低了复方中主要成分的毒性,（４）某些化学成学可形成复合物,（５）复方煎者过程中产生新成分的可能,（６）复方煎煮过程中对无机成分的影响。     

The Clinical Study of Healon 5 in Phacoemulsification and IOL Implantation

Purpose: To compare a new ophthalmic viscoelastic device (OVD) Healon 5 with two other kinds of OVDs commonly used in China during phacoemulsification and intraocular lens (IOL) implantation in terms of removal time, intraocular pressure, corneal and anterior chamber response.Methods: This prospective randomized study, in which patients and observers are masked, comprises niety eyes. They were randomly divided into 3 groups with different OVDs. Healon 5 (sodium hyaluronate 5 000 2.3%) was compared with Healon GV (sodium hyaluronate 7 000 1.4%) and Iviz (sodium hyaluronate 1.0%) . The surgeries were performed with temporal corneal incision, phacoemulsification in situ and foldable lens intracapsular implantation. The characteristic and the removal time of the viscoelastic material as well as the postoperative IOP, corneal reaction and anterior chamber reactions of the eyes were observed preoperatively and 24 hrs postoperatively. Exclusion criteria were glaucoma, a preoperative dilated pupil diameter small     

统计方法在钙镁磷肥原料采样分析中的应用

采用统计方法 ,针对原料磷矿个体差异 ,解决磷矿采样的代表性。根据原料质量的波动 ,对确定的采样分析频率 ,估算其平均值与实际值的差值 ,并为严格按照配方生产 ,计算折标消耗提供可靠的计算依据     

微波样ICP—MS测定海产品中元素方法研究

本文利用微波消解电感藕合等离子体质谱法（ICP－MS）测定了海产品中Na、Mg、Al、P、Cr、Mn、Fe、Ni、Ca、Zn、As、Sr、Mo、Cd、Pb、Hg,并利用国家标准物质贻贝GBW08571验证了方法的准确度、准确度在85％－115％,平均值为96．7％,测定值与标准值吻合,相对标准偏差均小于5％,并用多内标法有效地校正了基体干扰,方法简便、快速、准确、可靠。     

中药复方药效物质基础的研究方法与技术

中药复方化学物质基础的研究和药效模型的建立是中药现代化的关键问题。本文利用现代高效色谱方法及其联用技术对中药全成分范畴进行系统分离和分析,并结合药理实验,以阐明起作用的主要组成或成分,进一步利用制备色谱重组,对这些组分或成分进行药效验证和配伍优化。