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101.
102.
Current visualization design toolkits help users to explore data and create visualizations. However, most of these systems do not record the executed actions during the visualization construction process with semantic context. In this paper, we present VisAct, a visualization design system based on semantic actions, that helps average users to construct visualizations step by step. Our system contributes a set of action-based visualization components and a high-level grammar for semantic actions. VisAct also guides the visualization construction process and provides an action tracker for history management and data collection. We demonstrate the usability of VisAct by visualizations and a plugin application. Finally, we conduct a user study to evaluate the efficiency and effectiveness of our system. 相似文献
103.
Wei Wei Shu-Hua Yang Ze-Han Bao Chong Zhang Chang Gao Wei-Ru Fan 《中国物理C(英文版)》2020,44(9):094104-094104-10
104.
Ortiz Adolfo Yang Jianhua Coccolo Mattia Seoane Jesús M. Sanjuán Miguel A. F. 《Nonlinear dynamics》2020,102(4):2323-2337
Nonlinear Dynamics - The main purpose of this paper is to study both the underdamped and the overdamped dynamics of the nonlinear Helmholtz oscillator with a fractional-order damping. For that... 相似文献
105.
The etch-stop structure including the in-situ SiN and AlGaN/GaN barrier is proposed for high frequency applications.The etch-stop process is realized by placing an in-situ SiN layer on the top of the thin AlGaN barrier.F-based etching can be self-terminated after removing SiN,leaving the AlGaN barrier in the gate region.With this in-situ SiN and thin barrier etch-stop structure,the short channel effect can be suppressed,meanwhile achieving highly precisely controlled and low damage etching process.The device shows a maximum drain current of 1022 mA/mm,a peak transconductance of 459 mS/mm,and a maximum oscillation frequency(fmax)of 248 GHz. 相似文献
106.
采用基于密度泛函理论的第一性原理计算法研究了新型稀磁半导体Li_(1±)_y(Zn_(1-)_xFe_x)P (x=0, 0.0625;y=0, 0.0625)的电子结构、磁性及光学性质.结果表明,Fe的掺入使体系产生自旋极化杂质带,Fe的3d态与Li2s态,Zn4s态以及P3p态的态密度峰在费米能级处出现重叠,产生sp-d轨道杂化,此时体系净磁矩最大,材料表现出金属性,导电性增强.当Li空位时,导电性减弱,但杂质带宽度最大,居里温度最高.而Li填隙时,体系形成能最低,材料变为半金属性,表现为100%自旋注入,表明掺杂体系的磁性和电性可以分别通过Fe的掺入和Li的含量进行调控.对比光学性质发现,Li空位时,在介电函数虚部和复折射率函数的低能区出现新峰,扩大了对低频电磁波的吸收范围.能量损失函数表明掺杂体系具有明显的蓝移效应,且Li填隙时有更强的等离子共振频率. 相似文献
107.
Xiaofeng Zheng Xinyu Zhao Jie Huang Hao Yang Qinghui Wang Yuhang Liu Peiwei Gong Laijin Tian Hongping Xiao Zhe Liu 《应用有机金属化学》2020,34(12):e5981
The low-cost, high specific surface area and porosity, controlled pore size, and chemical properties of metal–organic framework (MOF) materials have attracted much attention in the exploration of proton conduction. The method of chemically modifying MOF structures or introducing conductive medium into the holes can effectively improve the proton conductivities of the materials. Here, the structural tunability of ionic liquid (IL) and flexible MOF (fle-MOF) materials are matched to give full play to the conductivity of IL, the framework support, and the microporous effect of MOFs, which achieves the synergistic effect of performance and expands the temperature range of proton transfer. Three kinds of CS/IL@fle-MOF membranes were prepared by combining three fle-MOFs with 1-carboxymethyl-3-methylimidazole (CMMIM) in different proportions to obtain 15 pieces of membranes. The comparative analyses show that CS/IL@fle-MOF membranes have excellent proton conduction performance at a wider temperature range (263–353 K) and lower relative humidity (75% RH). Among them, the proton conductivities of CS/CMMIM@MIL-88A-25% and CS/CMMIM@MIL-88B-125% are up to 1.33 and 1.42 S cm−1 at 75% RH and 353 K, respectively; whereas those of CS/CMMIM@MIL-53(Fe)-75% and CS/CMMIM@MIL-88B-125% reach up to 2.1 × 10−3 and 1.28 × 10−3 S cm−1 at 75% RH and 263 K, respectively. The Ea of CS/CMMIM@fle-MOFs is in the range of 0.1–0.5 eV, suggesting that the proton transport follows predominantly the typical Grotthuss transfer mechanism. The results of this study indicate that the CS/CMMIM@fle-MOF membranes combinations offer great potential for the design of composite porous proton-conducting materials. 相似文献
108.
Zhiyong Chen Mengmeng Wang Yuanyuan Yang Xiaomin Cui Jing Hu Ye Li Feng Zhao 《Biomedical chromatography : BMC》2020,34(2):e4726
Multicompound determination for the quality control of traditional Chinese medicine (TCM) may often be inadequate, since these compounds may not be associated with, or fully represent, the clinical effects of TCM. Moreover, the individual contributions of each constituent to the pharmacological effect are often not considered. In China, Porana sinensis is widely used as a substitute for Erycibe sources to treat joint pain and rheumatoid arthritis. The existing quality control methods for P. sinensis neither consider the individual contributions of various compounds nor control the actual quality associated with different clinical efficacies. In the present study, a novel efficacy-oriented approach, named the effect-constituent index (ECI), was established for P. sinensis. Analyses of the spectrum–effect relationship and components in rat plasma were conducted to systematically and scientifically select quality markers. Quantitative analysis of multicomponents via a single marker method was introduced to enhance the practical application value of the established ECI. The established ECI shows a good ability to distinguish and predict the bioeffect-based quality of P. sinensis. The present study also provides a reference for the establishment and application of ECI as a quality control method for TCMs. 相似文献
109.
Meining Li Huahua Li Hong Yang Rina Cheng Pengdou Zheng Rui Guo 《Biomedical chromatography : BMC》2020,34(4):e4799
Spermiogenesis in mammals is an exclusive process during which haploid round spermatids mature into spermatozoa in the testis. Any abnormality in the process of spermiogenesis may result in male infertility. The aim of the present study was to characterize the differentially expressed proteins between round and elongated spermatids in mice using label-free quantitative mass spectrometry. Of the 2411 proteins identified in this study, 333 were differentially expressed with a ≥10-fold change, including 208 upregulated proteins and 125 downregulated proteins in round spermatids relative to elongated spermatids. Gene Ontology analysis showed that these differentially expressed proteins were categorized into 10 types of subcellular localizations, 9 molecular functions, and were involved in 9 biological processes. All the identified proteins participated in 268 different pathways. In addition, ubiquitin-mediated proteolysis and the proteasome pathway, autophagy, lysosome, and apoptosis pathways were involved in the mechanism of spermiogenesis. Our data may provide valuable information for a better understanding of spermiogenesis and help improve the diagnosis and treatment of male factor infertility. 相似文献
110.
Wenping Huang Zhiqi Wen Qi Wang Renhao Chen Zhifeng Li Yulin Feng Shilin Yang 《Biomedical chromatography : BMC》2020,34(7):e4828
Kalimeris indica (L) Sch-Bip is a medicinal plant used by the Miao ethnic group in the Guizhou province of China. It is widely used as a fresh vegetable to treat colds, diarrhea and gastric ulcers. However, few studies have been conducted on the mechanism of its effect on colds, and its quality control. The anticomplement and antitussive activities of different polar extracts of K. indica were evaluated. Fifty-nine compounds, mainly including phenols and flavonoids, were identified in K. indica extract by ultra-high-performance liquid chromatography quadrupole time-of-flight tandem mass spectrometry. A method was established through ultra-high-performance liquid chromatography with a photodiode array to simultaneously determine the anticomplement and antitussive activity of five compounds in K. indica combining chemical identification with chemometrics for discrimination and quality assessment. Also, 3,5-dicaffeoylquinic acid and 4,5-dicaffeoylquinic acid exhibited significantly higher anticomplementary activity than the other three compounds. The quantitative data were further analyzed by principal component analysis and orthogonal partial least-squares discriminant analysis. Heatmap visualization was conducted to clarify the distribution of the major compounds in different geographical origins. Screening pharmacological activities by a combination of chemometrics and chemical identification might be an effective method for the quality control of K. indica. 相似文献