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551.
Recently, emotional electroencephalography (EEG) has been of great importance in brain–computer interfaces, and it is more urgent to realize automatic emotion recognition. The EEG signal has the disadvantages of being non-smooth, non-linear, stochastic, and susceptible to background noise. Additionally, EEG signal processing network models have the disadvantages of a large number of parameters and long training time. To address the above issues, a novel model is presented in this paper. Initially, a deep sparse autoencoder network (DSAE) was used to remove redundant information from the EEG signal and reconstruct its underlying features. Further, combining a convolutional neural network (CNN) with long short-term memory (LSTM) can extract relevant features from task-related features, mine the correlation between the 32 channels of the EEG signal, and integrate contextual information from these frames. The proposed DSAE + CNN + LSTM (DCRNN) model was experimented with on the public dataset DEAP. The classification accuracies of valence and arousal reached 76.70% and 81.43%, respectively. Meanwhile, we conducted experiments with other comparative methods to further demonstrate the effectiveness of the DCRNN method. 相似文献
552.
在大学物理实验中,测量不确定度是实验分析的一个重要内容.根据不确定度的分析过程,再结合具体的实验数据,分别对大学物理实验中弹性模量、液体表面张力系数和平凸透镜的曲率半径这3个具有代表性实验的不确定度进行了分析讨论.通过本文的分析,可以为大学物理实验教学和学生处理实验数据提供一个参考,同时能够锻炼学生处理实验数据的能力,也有助于培养学生的意志品质. 相似文献
553.
Risheng Li Wen Sun Longfei Xia Zia U Xubo Sun Zhao Wang Yujie Wang Xu Deng 《Molecules (Basel, Switzerland)》2022,27(22)
Activated carbon can be applied to the treatment of wastewater loading with different types of pollutants. In this paper, a kind of activated carbon in granular form (GAC) was utilized to eliminate antibiotics from an aqueous solution, in which Tetracycline (TC), Thiamphenicol (THI), and Sulfamethoxazole (SMZ) were selected as the testing pollutants. The specific surface area, total pore volume, and micropore volume of GAC were 1059.011 m2/g, 0.625 cm3/g, and 0.488 cm3/g, respectively. The sorption capacity of GAC towards TC, THI, and SMZ was evaluated based on the adsorption kinetics and isotherm. It was found that the pseudo-second-order kinetic model described the sorption of TC, THI, and SMZ on GAC better than the pseudo-first-order kinetic model. According to the Langmuir isotherm model, the maximum adsorption capacity of GAC towards TC, THI, and SMZ was calculated to be 17.02, 30.40, and 26.77 mg/g, respectively. Thermodynamic parameters of ΔG0, ΔS0, and ΔH0 were obtained, indicating that all the sorptions were spontaneous and exothermic in nature. These results provided a knowledge base on using activated carbon to remove TC, THI, and SMZ from water. 相似文献
554.
555.
Yajie Zhang Xiaohuan Cao Yang Gao Yujie Xie Zhihao Huang Zhengbiao Zhang Xiulin Zhu 《中国化学》2021,(5):1273-1280
Main observation and conclusion
The on-demand building copoiymer structures,from sequence to architecture,is crucial in understanding the relation between pol-y... 相似文献
556.
557.
Liu Jinxiang Ge Yujie Wang Guohua Liu Yingjiu Xu Xiaofeng 《Journal of Radioanalytical and Nuclear Chemistry》2021,330(3):871-882
Journal of Radioanalytical and Nuclear Chemistry - Uranium-containing wastewater poses a major threat to human health because of its toxicity and radioactivity. To address this issue, tea... 相似文献
558.
Luan Qian Zhang Hao Lei Yujie Cai Yixin Bao Yuping Li Yan Tang Hu Li Xiuting 《Cellulose (London, England)》2021,28(9):5735-5744
Cellulose - In this study, regenerated cellulose-based macrogels with abundant carboxyl groups and interconnected microporous structures were synthesized from cellulose fibers (CFs)/cellulose... 相似文献
559.
The skull defects are challenging to self-heal, and autologous bone graft repair has numerous drawbacks. The scaffolds for the rapid and effective repair of skull defects have become an important research topic. In this study, polyvinyl alcohol (PVA)/β-tricalcium phosphate(β-TCP) composite scaffolds containing icariin (ICA) were prepared through direct-ink three-dimensional (3D) printing technology. β-TCP in the composite scaffold had osteoconductive capability, and the ICA molecule had osteoinductive capacity. The β-TCP and ICA components in the composite scaffold can enhance the capability to repair skull defects. We show that ICA exhibited a slow-release behaviour within 80 days. This behaviour helped the scaffold to continuously stimulate the formation of new bone. The results of in vitro cell compatibility experiments showed that the addition of ICA molecules contributed to the adhesion and proliferation of MC-3T3-E1 cells. The level of alkaline phosphatase secretion demonstrated that the slow release of ICA can promote the osteogenic differentiation of MC-3T3-E1 cells. The introduction of ICA molecules accelerated the in situ bone regeneration in in vivo. It is concluded that the 3D-printed PVA scaffold with β-TCP and ICA has a wide range of potential applications in the field of skull defect treatment. 相似文献
560.
Wa Gao Dr. Li Shi Wentao Hou Cheng Ding Prof. Qi Liu Prof. Ran Long Haoqiang Chi Prof. Yongcai Zhang Xiaoyong Xu Xueying Ma Zheng Tang Prof. Yong Yang Prof. Xiaoyong Wang Prof. Qing Shen Prof. Yujie Xiong Prof. Jinlan Wang Prof. Zhigang Zou Yong Zhou 《Angewandte Chemie (Weinheim an der Bergstrasse, Germany)》2024,136(9):e202317852
One-unit-cell, single-crystal, hexagonal CuInP2S6 atomically thin sheets of≈0.81 nm in thickness was successfully synthesized for photocatalytic reduction of CO2. Exciting ethene (C2H4) as the main product was dominantly generated with the yield-based selectivity reaching ≈56.4 %, and the electron-based selectivity as high as ≈74.6 %. The tandem synergistic effect of charge-enriched Cu−In dual sites confined on the lateral edge of the CuInP2S6 monolayer (ML) is mainly responsible for efficient conversion and high selectivity of the C2H4 product as the basal surface site of the ML, exposing S atoms, can not derive the CO2 photoreduction due to the high energy barrier for the proton-coupled electron transfer of CO2 into *COOH. The marginal In site of the ML preeminently targets CO2 conversion to *CO under light illumination, and the *CO then migrates to the neighbor Cu sites for the subsequent C−C coupling reaction into C2H4 with thermodynamic and kinetic feasibility. Moreover, ultrathin structure of the ML also allows to shorten the transfer distance of charge carriers from the interior onto the surface, thus inhibiting electron-hole recombination and enabling more electrons to survive and accumulate on the exposed active sites for CO2 reduction. 相似文献