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71.
Phototherapy: Metal–Organic‐Framework‐Derived Mesoporous Carbon Nanospheres Containing Porphyrin‐Like Metal Centers for Conformal Phototherapy (Adv. Mater. 38/2016) 下载免费PDF全文
72.
Patterning of Discotic Liquid Crystals with Tunable Molecular Orientation for Electronic Applications 下载免费PDF全文
Cheng Zou Jingxia Wang Meng Wang Yuchen Wu Kehua Gu Zhihao Shen Guirong Xiong Huai Yang Lei Jiang Tomiki Ikeda 《Small (Weinheim an der Bergstrasse, Germany)》2018,14(21)
The large‐area formation of functional micropatterns with liquid crystals is of great significance for diversified applications in interdisciplinary fields. Meanwhile, the control of molecular alignment in the patterns is fundamental and prerequisite for the adequate exploitation of their photoelectric properties. However, it would be extremely complicated and challenging for discotic liquid crystals (DLCs) to achieve the goal, because they are insensitive to external fields and surface chemistry. Herein, a simple method of patterning and aligning DLCs on flat substrates is disclosed through precise control of the formation and dewetting of the capillary liquid bridges, within which the DLC molecules are confined. Large‐area uniform alignment occurs spontaneously due to directional shearing force when the solvent is slowly evaporated and programmable patterns could be directly generated on desired substrates. Moreover, the in‐plane column direction of DLCs is tunable by slightly tailoring their chemical structures which changes their self‐assembly behaviors in liquid bridges. The patterned DLCs show molecular orientation–dependent charge transport properties and are promising for templating self‐assembly of other materials. The study provides a facile method for manipulation of the macroscopic patterns and microscopic molecular orientation which opens up new opportunities for electronic applications of DLCs. 相似文献
73.
Xiaojing Liu Luting Liu Xiujie Hu Shuyun Zhou Rinat Ankri Dror Fixler Zheng Xie 《Nano Research》2018,11(3):1262-1273
Advanced biocompatible and robust platforms equipped with diverse properties are highly required in biomedical imaging applications for the early detection of atherosclerotic vascular disease and cancers. Designing nanohybrids composed of noble metals and fluorescent materials is a new way to perform multimodal imaging to overcome the limitations of single-modality counterparts. Herein, we propose the novel design of a multimodal contrast agent; namely, an enhanced nanohybrid comprising gold nanorods (GNRs) and carbon dots (CDs) with silica (SiO2) as a bridge. The nanohybrid (GNR@SiO2@CD) construction is based on covalent bonding between SiO2 and the silane-functionalized CDs, which links the GNRs with the CDs to form typical core–shell units. The novel structure not only retains and even highly improves the optical properties of the GNRs and CDs, but also possesses superior imaging performance in both diffusion reflection (DR) and fluorescence lifetime imaging microscopy (FLIM) measurements compared with bare GNRs or fluorescence dyes and CDs. The superior bioimaging properties of the GNR@SiO2@CD nanohybrids were successfully exploited for in vitro DR and FLIM measurements of macrophages within tissue-like phantoms, paving the way toward a theranostic contrast agent for atherosclerosis and cancer. 相似文献
74.
The microscopic character of melting for quasi–two dimensional N
2
adlayers on graphite is examined for surface densities 0.2 1, where the upper limit corresponds to a complete monolayer. A Monte Carlo method, with the multiple histogram procedure, is employed to determine various thermodynamic quantities. Using the calculated specific heats and selected order parameters, determined at various surface densities, the mechanism for melting is shown to be vacancy mediated. The somewhat unusual behavior of the melting temperature versus density is shown to be entirely due to the vacancy concentration and their topology. Because this is determined by the free energy, our analysis should be general. Preliminary results for Xe on graphite supports this claim. 相似文献
75.
76.
Jichao ShiAuthor VitaeGujin HuAuthor Vitae Yan SunAuthor VitaeMing GengAuthor Vitae Jie WuAuthor VitaeYufeng LiuAuthor Vitae Meiying GeAuthor VitaeJunchao TaoAuthor Vitae Meng CaoAuthor VitaeNing DaiAuthor Vitae 《Sensors and actuators. B, Chemical》2011,156(2):820-824
WO3 nanocrystals have been prepared by a sol-gel route and characterized by X-ray diffractometry, scanning electron microscopy, and transmission electron microscopy. The experimental results show that WO3 nanocrystals have a high crystallographic quality and a good dispersivity. The particles’ sizes are in the range of 25-100 nm. The fabricated WO3 nanocrystal-based sensors have an excellent sensitivity and selectivity to acetone, and display a rapid response and recovery characteristics. The developed sensors exhibit a detection limit down to 0.05 ppm at 300 °C, rendering a promising application in noninvasive diagnosis of diabetes. The response mechanism of the WO3 nanocrystal sensor to low concentration of acetone has been discussed based on the depletion layer model. 相似文献
77.
在维吾尔语中,词缀的数量有限且构词具有一定的规律性。为了提高维吾尔语词切分算法的性能,在一个词缀库的基础上,通过分析维吾尔语的基本构词规则,提出了一种改进的非监督维吾尔语词切分方法。该方法对词进行规则切分,采用MAP切分评价模型对规则切分打分,选取得分最高的规则切分作为该词的最终切分形式。在一个5000词的测试语料上进行了实验,实验结果表明,使用该方法进行维吾尔语词切分具有更高的准确率。 相似文献
78.
在反胶束体系中研究了菁染料的吸收光谱以及ω值对菁染料荧光光谱的影响.讨论了不同粒径的AgCl纳米粒子对反胶束体系中菁染料的吸附状态及J-聚集体形成的影响.特别研究了反胶束水团空间限定效应对菁染料荧光量子产率及J-聚集体的影响。 相似文献
79.
为了实现可持续发展的长远目标,结合我国十二五规划及科技发展规划,针对现有公共建筑的能耗高、污染大,管理效率低下的问题,首次提出一种基于有/无线混合传感网络的建筑流态数据监控及总体优化协同控制,以实现建筑绿色化的SGB(Smart Green Building)技术;把运行中的公共服务建筑作为整体系统考虑,将采集到的数据划分为信息流、能量流、物质流、人员流,并做分层处理,从系统级的角度,得到了复杂系统的全局最优化解决方案;从而实现既有建筑的节能、减排与高效管理的改造,满足绿色化与智能化的要求。 相似文献
80.
Jia Quan ZhenJun Zhou YanJie Liu JianGuo Li YueXue Ma JingTao Liang 《中国科学:技术科学(英文版)》2014,57(11):2236-2240
Along with the development of space science and technology,miniature liquid helium temperature long life cryocooler is a focus subject in cryogenic study.Since it is the precondition of space detection researches,institutions of space in many countries do the research on it.In this article,we designed a compound cooling system.A three-stage high frequency thermal coupled pulse tube cryocooler was used to precool a Joule-Thomson(JT)cryocooler.This system has no moving parts at low temperatures and is hence suitable for space operation.Liquid helium temperature was successfully achieved in both open loop and closed cycle experiments.In the closed cycle experiment,when 473 W electric power was inputted,the cooling system reached a no-load temperature of 4.4 K,and a cooling capacity of 11.6 mW was provided at 4.54 K.It is the first miniature liquid helium temperature JT cryocooler in China and the research achievement paves a way for the space application of ultra-long wave infrared detection and THz technologies. 相似文献