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61.
Xia-Bing Zhou Zhong-Qing Wang Xing-Wei Liang Min Zhang Guo-Dong Zhou 《计算机科学技术学报》2022,37(5):1146-1160
There has been a recent line of work to automatically detect the emotions of posts in social media. In literature, studies treat posts independently and detect their emotions separately. Different from previous studies, we explore the dependence among relevant posts via authors' backgrounds, since the authors with similar backgrounds, e.g., "gender", "location", tend to express similar emotions. However, personal attributes are not easy to obtain in most social media websites. Accordingly, we propose two approaches to determine personal attributes and capture personal attributes between different posts for emotion detection: the Joint Model with Personal Attention Mechanism (JPA) model is used to detect emotion and personal attributes jointly, and capture the attributes-aware words to connect similar people; the Neural Personal Discrimination (NPD) model is employed to determine the personal attributes from posts and connect the relevant posts with similar attributes for emotion detection. Experimental results show the usefulness of personal attributes in emotion detection, and the effectiveness of the proposed JPA and NPD approaches in capturing personal attributes over the state-of-the-art statistic and neural models. 相似文献
62.
Xiao Chen Minlan Yuan Yuting Wang Yan Zhou Xiaohong Sun 《International Journal of Food Science & Technology》2022,57(5):2670-2679
The present study aimed to evaluate the effect of fermentation and gastrointestinal digestion of three kinds of fermented kiwifruit pulps with different Lactobacillus (Lactobacillus plantarum, Lactobacillus acidophilus and Lactobacillus casei). The changes in bioactive substances (total phenolic acid, total flavonoid, vitamin C and the viable count), antioxidant capacity (DPPH, ABTS, hydroxyl radical and superoxide anion radical scavenging activity) and phenolic profiles (protocatechuic acid, protocatechualdehyde, chlorogenic acid, caffeic acid and p-coumaric acid) were detected. The result showed, compared to non-fermented kiwifruit pulp, fermentation with LP and LA had higher content of TPA, TF and VC, as well as antioxidant capacity. Fermentation with LP and the content of protocatechualdehyde, p-coumaric acid and chlorogenic acid were increased. However, after digestion, LP showed more effect in maintaining the content of antioxidants, antioxidant capacity and the viable count rather than LA. During digestion, the content of protocatechualdehyde and p-coumaric acid was increased in fermented samples compared with non-fermented samples. Overall, compared with LA and LC, LP is more suitable for the fermentation of kiwifruit pulp. 相似文献
63.
Baohua Yuan Lili Wei Lixia Yang Liangjiu Bai Huawei Yang Donglei Wei Feng Wang Wenxiang Wang Hou Chen 《Journal of the American Ceramic Society》2022,105(2):801-805
Solar steam generation has attracted considerable interest due to its easy accessibility and sustainability. However, dye molecules were gradually concentrated on bulk water or the surface of solar absorbers during the disposal of dye wastewater. Herein, LaB6/g-C3N4 composites were immobilized on porous cotton cloth, served as a solar absorber resistant to dye clogging. The optimal solar absorber possessed solar harvesting of 92.3% and showed great application potential in the field of the treatment of dye wastewater. This study presented a new approach for the treatment of dye wastewater. 相似文献
64.
采用超高效液相色谱⁃四极杆⁃飞行时间高分辨质谱(UPLC⁃Q⁃TOF)对4类不同类型的含聚对苯二甲酸乙二醇酯(PET)材质的食品接触材料在4 %乙酸和50 %乙醇模拟物中的迁移出的非挥发性未知物进行筛查解析。结果表明,产品在4 %乙酸模拟物的迁移风险远小于50 %乙醇模拟物,主要迁移物质为聚合单体形成的寡聚物,抗氧剂、润滑剂、胶黏剂等加工助剂以及生产加工、迁移过程中形成的非有意添加物(NIAS)物质;纯PET材质的产品迁移物质较少,多层复合材料迁移物质较多。复合材质的产品中,PET材质可能在生产时添加了己二酸、癸二酸、新戊二醇等物质,进行了改性处理;此外,部分迁移物质会与模拟物中的乙醇发生反应,生成新的NIAS物质。 相似文献
65.
66.
67.
Pengyu Xu Hao Wang Wenjun Cui Qiangguo Chen Bingtian Tu Xiahan Sang Weimin Wang Zhengyi Fu 《Journal of the American Ceramic Society》2022,105(6):3735-3739
Here we report a transparent dual-phase ZnO·2.7Al2O3 ceramic. The composite is pore-free and consists of thin nanosheets with a spinel phase and a hexagonal phase, while the two phases match closely in both lattice and refractive index. Such features result in excellent optical transmittance (maximum value >80% in the visible spectrum) at comparable phase volume. This work may provide a new thought for the rational structural design of optical nanocomposites. 相似文献
68.
Kelin Hu Feipeng Wang Yuyang Yan Hongcheng Liu Zijia Shen 《Ceramics International》2021,47(11):15228-15236
In this paper, a novel hybrid structure of Pd doped ZnO/SnO2 heterojunction nanofibers with hexagonal ZnO columns was one step synthesized from electrospun precursor nanofibers. Due to the synergistic effect of hexagonal ZnO, SnO2 and Pd, the structure exhibited excellent hydrogen (H2) gas sensing properties. At low-temperature of 120 °C, the response (Ra/Rg) to 100 ppm H2 gas exceeded 160, the response/recovery time was only 20 s and 6 s respectively and the limit of detection was only 0.5 ppm. Meanwhile, it also had good selectivity for H2 gas and excellent linearity. In addition, the materials were characterized by XRD, FESEM, HRTEM, XPS, and the synthesis mechanism and gas sensing mechanism were proposed. 相似文献
69.
Wen-Sen He Jiaxin Rui Qingzhi Wang Zhen-Yu Chen 《European Journal of Lipid Science and Technology》2021,123(7):2000398
Piceatannol has shown to be a strong antioxidant in vivo, however, its ability to suppress lipid oxidation in foods has not been examined. The present study is to examine the antioxidant effect of piceatannol on heated canola oil compared with that of butylated hydroxytoluene (BHT). The oxidation of canola oil is conducted at 60, 90, 120, and 150 °C by monitoring the depletion of oxygen, the decrease in unsaturated fatty acids, and the changes of primary and secondary oxidation products. Results demonstrated that piceatannol can suppress lipid oxidation of canola oil in a dose-dependent manner with its effect being more effective than BHT. Practical Applications: Lipid oxidation is a major factor in the deterioration of food quality. Synthetic antioxidants, such as BHT and butylated hydroxyanisole, are used to inhibit oxidation in foods, but their safety has been always concerned. Piceatannol has exhibited a strong antioxidant activity to attenuate lipid oxidation and it should be further explored for use as a natural antioxidant in foods. 相似文献
70.
Quan-Qi Yu Juan-Juan Gao Xue-Xian Lang Hong-Yao Li Prof. Ming-Qi Wang 《Chembiochem : a European journal of chemical biology》2021,22(6):1042-1048
The development of small molecules that can selectively target G-quadruplex (G4) DNAs has drawn considerable attention due to their unique physiological and pathological functions. However, only a few molecules have been found to selectively bind a particular G4 DNA structure. We have developed a fluorescence ligand Q1 , a molecular scaffold with a carbazole–pyridine core bridged by a phenylboronic acid side chain, that acts as a selective ascaris telomere antiparallel G4 DNA ASC20 ligand with about 18 nm blue-shifted and enhanced fluorescence intensity. Photophysical properties revealed that Q1 was sensitive to the microenvironment and gave the best selectivity to ASC20 with an equilibrium binding constant Ka=6.04×105 M−1. Time-resolved fluorescence studies also demonstrated that Q1 showed a longer fluorescence lifetime in the presence of ASC20. The binding characteristics of Q1 with ASC20 were shown in detail in a fluorescent intercalator displacement (FID) assay, a 2-Ap titration experiment and by molecular docking. Ligand Q1 could adopt an appropriate pose at terminal G-quartets of ASC20 through multiple interactions including π–π stacking between aromatic rings; this led to strong fluorescence enhancement. In addition, a co-staining image showed that Q1 is mainly distributed in the cytoplasm. Accordingly, this work provides insights for the development of ligands that selectively targeting a specific G4 DNA structure. 相似文献