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91.
In this work, we used the hydrothermal method to synthesize Eu3+ ion-doped cubic BaF2 nanorods, which is a luminescent material. The clubbed structures were well crystallized and exhibited face-centred cubic structures, as indicated by powder X-ray diffraction, scanning electron microscopy, electron diffraction, and transmission electron microscopy. The luminescent properties were studied, and local symmetry surrounding Eu3+ ions and electronic transition processes included. The results indicated that Eu3+ occupied only one C4ν site in nanorods.  相似文献   
92.
Volumetric H2-uptake measurements on an Mo2N (79 m2g–1) sample reduced at 673 K have been carried out and the uptake isotherms in the temperature range of 308–623 K have been determined. Both the total and reversible hydrogen uptake increased with the uptake temperature. The irreversible hydrogen uptake increased abruptly when the uptake temperature was raised up to 423 K. The maximum of irreversible hydrogen uptake was measured at 473 K. The HIR/Mo ratio calculated from the uptakes obtained in the temperature range of 308–623 K varies in the range of 0.0010–0.0202. One possible mechanism for hydrogen adsorption is proposed to be heterolytic dissociation on Mo-N paris, in which the molybdenum atoms are in unsaturated coordination.  相似文献   
93.
活性酚醛树脂中羟甲基含量的测定   总被引:12,自引:0,他引:12  
王锋  赵临五 《分析化学》1995,23(9):1063-1065
本文提出一种酚醛树脂中羟甲基含量的化学分析法,分别以^13CNMR和化学分析法测定酚醛树脂的羟甲基含量。将两种测试结果与已知的投料量进行比较,证明所建立的化学分析法可行。  相似文献   
94.
Two (1,3,4)-oxadiazole ligands have been prepared. In one case the oxadiazole ring is flanked by two o-aniline groups, and in the other case it is an extension of the first where the amines are condensed with 2-picolyl groups. A monometallic copper(II) complex of the former has been prepared, and its crystal structure was determined. A number of bimetallic copper(II), cobalt(II), and nickel(II) complexes of the di-deprotonated latter ligand were prepared and isolated. The crystal structure of the cobalt(II) complex bearing two acetate bridges is reported. The work demonstrates that the seldom-employed oxadiazole ring can be used effectively for generating bimetallic complexes.  相似文献   
95.
96.
With the advent of the big data era, information storage and security are becoming increasingly important. However, high capacity information storage and multilevel anti-counterfeiting are typically difficult to achieve simultaneously. To address this challenge, herein, two electrochromic and electrofluorochromic dual-functional polymers with aggregation-induced emission (AIE) characteristics were rationally designed and facilely prepared. Upon applying voltages, the absorption and fluorescence spectra of the AIE polymers can undergo reversible changes, accompanied by variation of their color and emission. By utilizing the controllable characteristics of the polymers, dual-mode display devices were fabricated via a simple spraying technique. More interestingly, a four-dimensional color code device was constructed by adding color change multiplexing to the two-dimensional space, thereby achieving high capacity information storage. Moreover, the color code device can also be applied in the multilevel anti-counterfeiting area. The encrypted information can be dynamically converted under different voltages. Thus, the AIE polymers show great promise for applications in multidimensional information storage and dynamic anti-counterfeiting, and the design strategy may provide a new avenue for advanced information storage and high security technology.

By using electrical stimuli-responsive AIE polymers, dual-mode display devices, multidimensional information storage and anti-counterfeiting devices were constructed.  相似文献   
97.
Abstract

Poria cocos is an edible medicinal mushroom with the effects of inducing diuresis, excreting dampness, invigorating the spleen and tranquilizing the mind. The triterpenoids of Poria cocos as the main active ingredients have shown health benefits of the central nervous system of the human body. Accordingly, this study aimed at further understanding the antidepressant-like effect and a potential mechanism of the triterpenoids extracts from Poria cocos (TPC). As a result, the TPC significantly ameliorated depression-like behaviors on chronic unpredictable mild stress (CUMS) rats, and restored the levels of brain-derived neurotrophic factor and nerve growth factor in the hippocampus of rats. Gut microiota analysis revealed that TPC could increase the biodiversity and markedly regulate the relative abundance of [Prevotella], Allobaculum and Ochrobactrum of CUMS rats. The cecal contents metabolomics pointed to thirteen biomarkers associated with TPC antidepressant effect, which involved in primary bile acid biosynthesis, taurine and hypotaurine metabolism, arginine and proline metabolism. Correlation analysis further showed that there was a strong correlation relationship between the gut microbiota and the cecal contents metabolites, especially compounds involved in energy metabolism, inflammation and immunity. In conclusion, TPC showed a potential antidepressant effect, which was possibly mediated the gut microbiota and cecal contents metabolism.  相似文献   
98.
Deng  Chang-Song  Huang  Xing 《Potential Analysis》2022,56(2):213-226
Potential Analysis - Using coupling by change of measure and an approximation technique, Wang’s Harnack inequalities are established for a class of functional SDEs driven by subordinate...  相似文献   
99.
针对医用高值耗材种类繁多、管理难度大的问题,为减少人力成本、提高医用高值耗材的智能化管理水平。本文提出了基于物联网的高值医用耗材智能屋的管理系统,介绍了智能屋的整体架构、系统功能、核心业务及流程设计,主要分为结构模块、RFID模块、数据库模块、控制系统模块四大模块,具体有用户管理、出入库管理、综合查询、预警管理四大业务,通过GM(1,1)模型对2022年全年高值医用耗材的月消耗量进行预测分析,并且检验得该预测模型的精度等级为一级,模型预测效果很好,能够为医院采购人员采购提供了一个参考,避免因过度的主观估计而造成的耗材浪费。该系统能够有效地提高医院对于高值医用耗材的管理水平,减少人力、物力和财力的消耗,为广大患者提供更加优质的医疗服务。本文所提的高值医用耗材智能屋管理系统解决了传统的高值医用耗材管理的诸多难题。  相似文献   
100.

As an important research direction, operational research (OR) has always attracted scholars worldwide. We study the structure, trend and prospect in the OR field by conducting a bibliometric analysis of publications in the period of 1952–2020, which are included in the Web of Science (WoS) database. Using three effective bibliometric tools, namely, VOS viewer, CiteSpace, and Bibliometrix, a total of 5,353 publications were retrieved to show clear visual results using a series of scientific analyses. First, a performance analysis revealed the basic characteristics of publications considering the type distribution, annual trend, quantity and quality. Then, a cooperation analysis presented the influential countries/regions and showed the relationships among countries/regions, institutions and authors during different periods based on bibliometric indicators and co-authorship networks. Moreover, a keyword analysis was conducted to investigate the hot topics and development of the OR field, using co-occurrence analysis, timeline view analysis and evolution analysis. Finally, we discussed the implications and limitations, and summarized the main findings. This study hopes to provide important and valuable references for future research on the OR field.

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