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排序方式: 共有479条查询结果,搜索用时 15 毫秒
471.
472.
详细分析了<中国图书馆分类法>中图书分类编目的树形结构,如何将这种树形结构的数据写入TreeView拉件中,以及程序的改进优化方法. 相似文献
473.
Wei Yu Jing Li Tun Seng Herng Zishen Wang Xiaoxu Zhao Xiao Chi Wei Fu Ibrahim Abdelwahab Jun Zhou Jiadong Dan Zhongxin Chen Zhi Chen Zejun Li Jiong Lu Stephen J. Pennycook Yuan Ping Feng Jun Ding Kian Ping Loh 《Advanced materials (Deerfield Beach, Fla.)》2019,31(40)
Among van der Waals layered ferromagnets, monolayer vanadium diselenide (VSe2) stands out due to its robust ferromagnetism. However, the exfoliation of monolayer VSe2 is challenging, not least because the monolayer flake is extremely unstable in air. Using an electrochemical exfoliation approach with organic cations as the intercalants, monolayer 1T‐VSe2 flakes are successfully obtained from the bulk crystal at high yield. Thiol molecules are further introduced onto the VSe2 surface to passivate the exfoliated flakes, which improves the air stability of the flakes for subsequent characterizations. Room‐temperature ferromagnetism is confirmed on the exfoliated 2D VSe2 flakes using a superconducting quantum interference device (SQUID), X‐ray magnetic circular dichroism (XMCD), and magnetic force microscopy (MFM), where the monolayer flake displays the strongest ferromagnetic properties. Se vacancies, which can be ubiquitous in such materials, also contribute to the ferromagnetism of VSe2, although density functional theory (DFT) calculations show that such effect can be minimized by physisorbed oxygen molecules or covalently bound thiol molecules. 相似文献
474.
Appearance-based methods have been proven to be useful for face recognition tasks. The main problem with appearance-based methods originates from the multimodality of face images. It is known that images of different people in the original data space are more closely located to each other than those of the same person under different imaging conditions. In this paper, we propose a novel approach based on the nonlinear manifold embedding to define a linear subspace for illumination variations. This embedding based framework utilizes an optimization scheme to calculate the bases of the subspace. Since the optimization problem does not rely on the physical properties of the factor, the framework can also be used for other types of factors such as pose and expression. We obtained some promising recognition results under changing illumination conditions. Our error rates are comparable with state of art methods. 相似文献
475.
Poly(N‐isopropylacrylamide) (NIPAAm) is well known as a smart material with good thermal sensitivity and favorable biocompatibility. A series of new smart hydrogels, NIPAAm copolymerized with IAM (itaconamic acid; 4‐amino‐2‐methylene‐4‐oxobutanoic acid), were synthesized through radical solution polymerization in this work. Poly(NIPAAm‐co‐IAM) can respond to the changes of temperature as well as pH value. Such a characteristic is due to the fact that IAM contains not only a hydrophilic acrylic acid moiety but also an acrylamide moiety to be thermal and pH sensitive. The experimental results show that the lower critical solution temperature (LCST) of the copolymer increases as the molar fraction of IAM increases. Moreover, based on the current experimental data, 3 wt % of Poly(NIPAAm‐co‐IAM) aqueous solution in this study exhibits a phase transition temperature (37.8°C) close to the human body temperature in the buffer solution of pH 7 possibly to be useful in drug delivery. © 2015 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2015 , 132, 42367. 相似文献
476.
Image analysis methods are widely used tools for an objective pilling evaluation. However, due to their intrinsic limitations, simple image analysis of digital photographs is not a suitable procedure for the pilling evaluation of fabrics with complex structures and distinct patterns. Generally, a fabric pattern or a complex fabric structure have presented significant problem to the pills detection. This paper describes a system of the objective pilling evaluation of unicolor fabrics and even fabrics with complex patterns. The main points of the pilling evaluation system include a 3D fabric surface reconstruction from shading based on gradient field method, using image analysis tools for the pills detection and an estimation of an objective pilling grade. In order to enable the estimation of the objective pilling grade, a relationship between the pilling grades obtained by a subjective method and selected pill characteristics was specified using a linear regression model. The method was tested on a set of different fabrics and estimated pilling grades were compared with subjective pilling grades of the samples. Results showed that the proposed method is suitable and reliable tool for the objective pilling evaluation of various types of fabrics. 相似文献
477.
Kawasue Kikuhito Wai Pwint Phoo Win Khin Dagon Lee Geunho Iki Yusuke 《Artificial Life and Robotics》2023,28(1):89-95
Artificial Life and Robotics - Pig weights are important indicator for the healthcare and the economic operation of pig farms, and the development of a system to easily estimate these weights is... 相似文献
478.
Sheng Ye Quanle Cao Panxianzhi Ni Shuting Xiong Meng Zhong Tun Yuan Jing Shan Jie Liang Yujiang Fan Xingdong Zhang 《Small (Weinheim an der Bergstrasse, Germany)》2023,19(40):2302152
Cell migration is an essential bioactive ceramics property and critical for bone induction, clinical application, and mechanism research. Standardized cell migration detection methods have many limitations, including a lack of dynamic fluid circulation and the inability to simulate cell behavior in vivo. Microfluidic chip technology, which mimics the human microenvironment and provides controlled dynamic fluid cycling, has the potential to solve these questions and generate reliable models of cell migration in vitro. In this study, a microfluidic chip is reconstructed to integrate the bioactive ceramic into the microfluidic chip structure to constitute a ceramic microbridge microfluidic chip system. Migration differences in the chip system are measured. By combining conventional detection methods with new biotechnology to analyze the causes of cell migration differences, it is found that the concentration gradients of ions and proteins adsorbed on the microbridge materials are directly related to the occurrence of cell migration behavior, which is consistent with previous reports and demonstrates the effectiveness of the microfluidic chip model. This model provides in vivo environment simulation and controllability of input and output conditions superior to standardized cell migration detection methods. The microfluidic chip system provides a new approach to studying and evaluating bioactive ceramics. 相似文献
479.
Challenges Based on Antiplasmodial and Antiviral Activities of 7-Chloro-4-aminoquinoline Derivatives
Dr. Satoshi Mizuta Dr. Farhana Mosaddeque Dr. Mya Myat Ngwe Tun Dr. Awet Alem Teklemichael Mayumi Taniguchi Masashi Hosokawa Tomoko Yamaguchi Dr. Juliann Makau Dr. Nguyen Tien Huy Dr. Shusaku Mizukami Prof. Noriyuki Nishida Prof. Kouichi Morita Prof. Kenji Hirayama 《ChemMedChem》2023,18(7):e202200586
We report the structural functionalization of the terminal amino group of N1-(7-chloroquinolin-4-yl) butane-1,4-diamine, leading to a series of 7-chloro-4-aminoquinoline derivatives, and their evaluation as potent anti-malarial and anti-viral agents. Some compounds exhibited promising anti-malarial effects against the Plasmodium falciparum 3D7 (chloroquine-sensitive) and Dd2 (chloroquine-resistant) strains. In addition, these compounds were assayed in vitro against influenza A virus (IAV) and severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). Compound 5 h , bearing an N-mesityl thiourea group, displayed pronounced anti-infectious effects against malaria, IAV, and SARS-CoV-2. These results provide new insights into drug discovery for the prevention or treatment of malaria and virus co-infection. 相似文献