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51.
Ruochen Lan Qian Wang Chen Shen Rui Huang Jinying Bao Zhongping Zhang Lanying Zhang Huai Yang 《Advanced functional materials》2021,31(51):2106419
Stimuli-responsive photonic crystals (PCs) have been extensively studied due to their potential in fabrication of anti-counterfeiting devices and information storage. In this work, using Ca2+ ionic crosslinker, a cholesteric liquid crystalline network (CLCN) based PC able to simultaneously present visible and fluorescence pattern by moisture treatment is designed and prepared. The circularly polarized light from helical structure of CLCN makes the reflected pattern distinguishable under different circular polarizer, implying the unique advantage of this novel coating as anti-counterfeiting devices. More importantly, due to the thermochromic property of the liquid crystal monomers, permanent pattern is achievable by chemically crosslinking specific region at different temperature. By integrating chemically crosslinking and physically ionic crosslinking, a permanent pattern and a dynamic humidity responsive pattern can be incorporated in a single device, indicating the great potential of this novel photonic coating in information storage. 相似文献
52.
Those who have been convicted of crimes are subjected to a stigma that affects many aspects of their social lives. The “felon” label brings collateral consequences that make it difficult to obtain basic human needs, including housing. This study uses the audit method to examine the effects of race, gender, and criminal history on housing outcomes. Testers, exhibiting characteristics suggestive of race and gender and disclosing one of three offenses, placed phone calls to rental property owners across the Midwest to inquire about renting a property. We found powerful negative effects for those with a criminal record seeking apartments, regardless of whether the offense was sexual or drug-related. However, we found no differences between minority and non-minority testers. We explain these findings in the context of housing as an essential resource for formerly incarcerated individuals. 相似文献
53.
This study aims to examine the practicality of a novel passive heat transport system “thermosyphon heat transport device” (THTD). It is a fluid-filled unit, with both source and sink amalgamated within it. A vertical tube-in-tube design has been incorporated, consisting of heat source, adiabatic height, and sink. To showcase the performance, a transient numerical analysis is performed using ANSYS Fluent, which is compared with the simple closed thermosiphon (SCT) for heat transport capability (1 kW) and different adiabatic heights (0.25, 1, and 1.5 m). Also, the influence of axial conduction is examined. The proposed Therminol VP1-based THTD has better heat transport capability over SCT due to a uniform flow pattern. Although the time response diminishes with adiabatic height, the novelty is justified as the heat gained by THTD (adiabatic height: 1.5 m) is 1.5 times more than SCT. Furthermore, the THTD performance is experimentally analyzed by varying the coolant flow rate (0.01, 0.02, and 0.03 kg/s), heat load (100−600 W), and transport distance (0.25 and 0.75 m), which yielded 80%−90% energy efficiency. As the THTD is crucial for a conceptual solar indoor cooker, the response under transient heating/cooling conditions is also investigated, which depicted 300 s for transient heating and 10−50 s for transient cooling. 相似文献
54.
Alison Jee Samantha Christine Sernoskie Jack Uetrecht 《International journal of molecular sciences》2021,22(6)
Idiosyncratic drug-induced liver injury (IDILI) remains a significant problem for patients and drug development. The idiosyncratic nature of IDILI makes mechanistic studies difficult, and little is known of its pathogenesis for certain. Circumstantial evidence suggests that most, but not all, IDILI is caused by reactive metabolites of drugs that are bioactivated by cytochromes P450 and other enzymes in the liver. Additionally, there is overwhelming evidence that most IDILI is mediated by the adaptive immune system; one example being the association of IDILI caused by specific drugs with specific human leukocyte antigen (HLA) haplotypes, and this may in part explain the idiosyncratic nature of these reactions. The T cell receptor repertoire likely also contributes to the idiosyncratic nature. Although most of the liver injury is likely mediated by the adaptive immune system, specifically cytotoxic CD8+ T cells, adaptive immune activation first requires an innate immune response to activate antigen presenting cells and produce cytokines required for T cell proliferation. This innate response is likely caused by either a reactive metabolite or some form of cell stress that is clinically silent but not idiosyncratic. If this is true it would make it possible to study the early steps in the immune response that in some patients can lead to IDILI. Other hypotheses have been proposed, such as mitochondrial injury, inhibition of the bile salt export pump, unfolded protein response, and oxidative stress although, in most cases, it is likely that they are also involved in the initiation of an immune response rather than representing a completely separate mechanism. Using the clinical manifestations of liver injury from a number of examples of IDILI-associated drugs, this review aims to summarize and illustrate these mechanistic hypotheses. 相似文献
55.
Effects of injection parameters on propagation patterns of hydrogen-fueled rotating detonation waves
《International Journal of Hydrogen Energy》2022,47(91):38811-38822
Two-dimensional rotating detonation waves (RDWs) with separate injections of hydrogen and air are simulated using the Navier–Stokes equations together with a detailed chemical mechanism. The effects of injection stagnation temperature and slot width on the detonation propagation patterns are investigated. Results find that extremely high temperatures can lead to a chaotic mode in which detonation waves are generated and extinguished randomly. Increasing the slot width can reduce the number of detonation waves and finally trigger detonation quenching at a low injection stagnation temperature. But increasing the slot width can change the RDW propagation pattern from a chaotic to a stable mode under high injection temperature. Furthermore, the kinetic parameter τ (representing the chemical reactivity of the mixture) and the kinematic parameter α (representing the mixing efficiency of hydrogen and oxygen) are introduced to distinguish the RDW propagation patterns. 相似文献
56.
遥感影像的地块背景特征复杂,当前地块分割方法不能较好地处理模糊的边缘信息,导致分割精度不理想;文章利用注意力机制处理地块特征,提出了一种基于全局坐标注意力机制的遥感地块分割网络:GCAT-U-Net;该方法在U-Net网络基础上嵌入了全局坐标注意力机制,加强了深度神经网络对于遥感影像数据中重要特征的关注度;在公开的GID数据集上的实验结果表明,文章提出的模型将准确率从0.9041提升到了0.9227,比传统U-Net网络提高了2百分点;结合特征自身重要性和特征位置信息的全局坐标注意力机制有助于更精确的目标定位,其输出相较于嵌入单一注意力机制,地块边界更为清晰,提升效果更为显著。 相似文献
57.
卢晓丽 《网络安全技术与应用》2014,(2):56-57
无线局域网通过无线方式发送和接收数据,尽量减少了对固定线路的依赖。这种业务服务的主要对象是在某些需要得到数据服务但缺乏有线数据接入条件的环境,如会议中心、展览中心、机场和酒店等。 相似文献
58.
MVVM 设计模式及其应用研究磁 总被引:1,自引:0,他引:1
陈涛 《计算机与数字工程》2014,(10)
MVVM 即 Model-View-ViewModel ,是微软 WPF 和 Silverlight 应用特有的一种界面设计模式。使用 MVVM设计模式可以帮助我们分离业务逻辑,显示逻辑和用户界面,使得我们的程序代码结构清晰,容易被阅读、测试、维护、替换、扩展和改进。论文意在通过逐层分解对 MVVM 及其应用进行研究。 相似文献
59.
In this paper, we deal with the problem of classification of interval type-2 fuzzy sets through evaluating their distinguishability. To this end, we exploit a general matching algorithm to compute their similarity measure. The algorithm is based on the aggregation of two core similarity measures applied independently on the upper and lower membership functions of the given pair of interval type-2 fuzzy sets that are to be compared. Based on the proposed matching procedure, we develop an experimental methodology for evaluating the distinguishability of collections of interval type-2 fuzzy sets. Experimental results on evaluating the proposed methodology are carried out in the context of classification by considering interval type-2 fuzzy sets as patterns of suitable classification problem instances. We show that considering only the upper and lower membership functions of interval type-2 fuzzy sets is sufficient to (i) accurately discriminate between them and (ii) judge and quantify their distinguishability. 相似文献
60.
Sacha inchi (Plukenetia volubilis L., Euphorbiaceae) seed oil is rich in α-linolenic acid, a kind of n-3 fatty acids with many health benefits. To discover the mechanism underlying α-linolenic acid accumulation in sacha inchi seeds, preliminary research on sacha inchi seed development was carried out from one week after fertilization until maturity, focusing on phenology, oil content, and lipid profiles. The results suggested that the development of sacha inchi seeds from pollination to mature seed could be divided into three periods. In addition, investigations on the effect of temperature on sacha inchi seeds showed that total oil content decreased in the cool season, while unsaturated fatty acid and linolenic acid concentrations increased. In parallel, expression profiles of 17 unsaturated fatty acid related genes were characterized during seed development and the relationships between gene expression and lipid/unsaturated fatty acid accumulation were discussed. 相似文献