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1.
手性是指物质分子互成镜像但无法重合的性质,手性对映体在生物体内因不同的手性识别而呈现截然不同的作用,所以手性识别在生命科学、医药、食品及材料等领域均具有十分重要的科学意义。手性电化学传感器由于具有制备简单、检测快速和响应灵敏等优点而引起广泛的关注。手性识别材料是构建手性电化学传感器的基础,因此有关手性识别材料的研究在手性电化学检测中尤为重要。综述了近五年手性电化学传感器的研究进展,详细介绍了多种手性识别材料的具体应用,并对该领域的发展前景进行了展望,旨在为今后手性电化学传感器的设计提供参考。  相似文献   
2.

Fe-based bulk metallic glasses (BMGs) with high boron content have potential application as a coating material used in the framework for storing spent nuclear fuels to support their safe long-term disposal. The high glass forming ability (GFA) and large supercooled liquid region are therefore required for such Fe-based BMGs in either the glassy powder fabrication or the subsequent coating spraying. In order to meet these requirements, the influence of Nb content on the GFA of Fe57Cr10Zr8B18Mo7−xNbx (x=1–5, at.%) alloys was investigated, as Nb has positive roles in GFA and thermal stability of BMGs. The results indicate that a fully amorphous phase in the as-cast samples with 3 mm in diameter is obtained for both the Fe57Cr10Zr8B18Mo5Nb2 and Fe57Cr10Zr8B18Mo4Nb3 alloys. The corresponding supercooled liquid regions of the two BMGs are 78 K and 71 K, respectively. The mechanism for improving their GFA was analyzed based on the principle of metal solidification, the parameters for glass formation and thermal properties of the alloys. The compression strength and Vicker’s hardness of the two BMGs are 1,950 MPa and 1,310 HV, 2,062 MPa and 1,180 HV, respectively. The developed BMGs with high B content, good GFA, and very high hardness can be used as coating materials to the framework for spent nuclear fuels.

  相似文献   
3.
介绍了高分子材料导热性能影响因素研究进展,重点阐释了聚合物基体的结构特性(链结构、分子间相互作用、取向、结晶度等)、导热填料(种类、含量、形态、尺寸等)以及制备方法等对高分子材料导热性能的影响。  相似文献   
4.
张璐璐  谭伯川  李文坡 《化工学报》2021,72(10):5402-5411
采用简单的一步电沉积方法制备了Cu2+掺杂的MnO2材料。通过XRD、SEM、TEM等方法对材料进行了表征,结果表明其具有蓬松多孔的纳米结构,作为电池正极材料时有利于Zn2+的存储,具有较高的电池容量。与未掺杂样品相比Cu2+掺杂的MnO2材料有更好的电化学性能,在电流密度为200 mA/g时,比容量达到235 mAh/g,增加了47.8%,阻抗也由997.3 Ω降到了564.3 Ω。  相似文献   
5.
王欣  赵鹏  李清扬  田平芳 《化工学报》2021,72(5):2426-2435
半导体合成生物学是研究半导体技术与合成生物学之间协同作用的一门交叉学科。其涉及的活细胞-半导体材料杂合体系具有独特的能量和信号转导机制,不仅维持活细胞的代谢能力,而且保留半导体材料的光电学物理特性,在化工、通讯、计算、能源及医疗等领域具有广阔的应用前景。综述了半导体合成生物学在生物催化、智能生物传感以及新型DNA数据存储领域的最新研究进展,讨论了目前研究面临的技术难题及解决方案,旨在为合成生物学和半导体技术这两个影响化工发展的领域提供有价值的参考。  相似文献   
6.
For the purpose of developing biodegradable magnesium alloys with suitable properties for biomedical applications, Mg–Zn–Ca–Cu metallic glasses were prepared by copper mold injection methods. In the present work, the effect of Cu doping on mechanical properties, corrosion behavior, and glass-forming ability of Mg66Zn30Ca4 alloy was studied. The experimental findings demonstrated that the incorporation of Cu decreases the corrosion resistance of alloys, but increases the microhardness and degradation rate slightly. However, the addition of a trace amount of Cu can make the samples have antibacterial properties. Therefore, Mg–Zn–Ca–Cu has great advantages in clinical implantation and is the potential implant material.  相似文献   
7.
《Ceramics International》2021,47(23):32710-32719
The formation of micro-cracks in Ni-rich LiNi0.8Co0.1Mn0.1O2 (NCM811) cathode particles is an extremely important factor affecting the electrochemical characteristics after long-term cycling. Generally, cracks can be divided into intergranular crack and intracrystalline crack according to their positions. Coating has been confirmed as a highly effective strategy to relieve intergranular cracks. However, the intracrystalline cracks of primary-like particles have rarely been studied. In this work, ethoxy functional polysiloxane (EPS) was directly coated on the surface of original NCM811 by tetraethyl orthosilicate (TEOS) hydrolytic polycondensation method without any additives. Then, the microstructure, micromorphology, surface state and electrochemical properties were investigated in detail by XRD, SEM, TEM, CV and EIS. The results displayed that the micro-cracks of primary-like particles were effectively suppressed under appropriate EPS coating. Accordingly, excellent capacity retention of 95.6% (100 cycles, 1C) and rate performance (144.6 mA h/g, 5C) were obtained. These improved mechanical and electrochemical properties are considered to be related to the EPS stress buffer layer, suppressed oxygen vacancies, inhibited phase transition and reduced volume change.  相似文献   
8.
洪帆  宋洁  杜冰  郑环达  郑来久 《精细化工》2021,38(12):2377-2384
细菌纤维素(BC)是微生物生长过程中产生的以葡萄糖为基本骨架的结构性碳水化合物,具有高纯度、高聚合度、高结晶度、高持水性、高抗张强度和良好的机械强度,在功能材料领域显示了巨大的应用潜力.综述了近年来BC合成菌种筛选的研究现状;分析了BC在透气、吸湿排汗、力学性能和染色与脱色性能调控方面的进展情况;重点总结了BC基材料在抗菌、防紫外线、防辐射、防静电、拒水拒油、导电和传感等功能化改性方面的研究进展;最后,指出BC大规模高效成模和成型技术、差异化高功能BC材料制备技术是未来的重点研发方向.  相似文献   
9.
The glass-to-mold adhesion in precision glass molding could severely degrade the quality of molded optics and shorten the lifespan of the precious molds. Since the consequences of adhesion take effect during the separation between glass and molds, it is important to investigate the debonding behaviors of a typical glass molding interface. To this end, here we perform a probe tack test procedure for borosilicate glass BK7, where debonding is conducted at molding temperature and specific velocity. We fully characterize the debonding behaviors using the peak adhesion stress σmax and the work of debonding Wdeb. Experiments show that when temperature is decreased from 690°C to 655°C at 10 μm/s, σmax continuously increases, while Wdeb first increases but then sharply decreases. When the debonding velocity is increased from 10 to 50 μm/s at 680°C, σmax also increases while Wdeb overall decreases. Therefore, the debonding behaviors are highly temperature and rate dependent. More importantly, depending on the debonding conditions, three debonding types are identified, that is, the cohesive bulk deformation, the cohesive-interfacial transition and the interfacial fracture. The cohesive type can be converted into the interfacial fracture, by either decreasing temperature or increasing the debonding velocity. Based on the Wdeb criterion, the three debonding regimes can be clearly distinguished. Finally, analyses on the temperature and velocity experimental results are unified by incorporating the reduced crack velocity aTvc. The dependences of both viscoelasticity and Wdeb on aTvc qualitatively explain the transition condition for different debonding types. Concerning these findings, the work of debonding not only supplements the characterization of adhesion strength, but also throws insightful light on revealing the debonding mechanisms.  相似文献   
10.
以聚氯乙烯(PVC)为基体,对苯二甲酸二辛酯(DOTP)为增塑剂,与无机填料CaCO3、钙锌热稳定剂、乳化剂OP-10、润滑剂液体石蜡等复合改性制备PVC基阻尼材料,采用动态流变仪DHR、动态热机械分析仪DMA、扫描电镜SEM等对试样的性能和形态进行表征。运用正交设计探究各组分对性能的影响规律,结果表明,填料CaCO3和增塑剂DOTP比例对其阻尼性能影响最显著;当PVC: CaCO3: DOTP: OP-10比重为45: 33: 22: 2时,25℃时频率0.01~150 Hz范围内,tan δ最大值从0.497提高到0.604;剪切速率0.1 s-1时表观黏度为3738 Pa·s,剪切速率150 s-1时表观黏度为2.19 Pa·s,具有优异的抗流挂性与稳定性。通过LASD形态分析构建微观聚集态模型,提出刚性填料团聚-解团聚和聚合物微球变形对流变性能的作用机理,为LASD的持续研究提供技术思路和理论基础。  相似文献   
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