期刊：
Journal of Alloys and Compounds,2022年911:165092 ISSN：0925-8388
通讯作者：
Jiayong Si<&wdkj&>Gemei Cai
作者机构：
[Si, Jiayong; Zhang, Zhizhong; Tang, Jiamin] Cent South Univ Forestry & Technol, Coll Mech & Elect Engn, Changsha 410004, Hunan, Peoples R China.;[Cai, Gemei; Li, Guihua] Cent South Univ, Sch Mat Sci & Engn, Changsha 410083, Hunan, Peoples R China.;[Zhou, Tianliang] Xiamen Univ, Coll Mat, Xiamen 361005, Fujian, Peoples R China.
通讯机构：
[Jiayong Si] C;[Gemei Cai] S;School of Materials Science and Engineering, Central South University, Changsha, Hunan 410083, China<&wdkj&>College of Mechanical and Electrical Engineering, Central South University of Forestry and Technology, Changsha, Hunan 410004, China
摘要：
High thermal stability and quantum efficiency are the two very significant factors for phosphors when concerning all kinds of related applications. Therefore, it is still main research topics as long as referencing to the luminescence phosphors. It is well known that deep trap and large band gap are beneficial to excellent thermal stability. In this work, a series of Na2BaCa1-xSrx(PO4)2:0.03Eu(2+) phosphors have been prepared by traditional solid state reaction. When the Sr2+ content increases, the emission intensity exhibits a blue shift phenomenon with the highest peak around 448 nm caused by the varied centroid shift (epsilon(c)) and the crystal field splitting (epsilon(cfs)). The thermal stability of Na2BaCa0.2Sr0.8(PO4)(2):0.03Eu(2+) phosphor still approaches to 100.3% of that room temperature at 150 degrees C, while the external and internal quantum efficiency are greatly enhanced from 19.92% to 62.53%. It is due to the effect of the cation disorder by introducing the high level of Sr ion, which create the deep trap and broaden the bandgap, resulting in the anti-thermal quenching behavior and enhanced quantum efficiency. Moreover, Rietveld refinements, microstructure, decay curves and thermoluminescence are also adopted to shed light on related mechanism of luminous performance. Furthermore, a pc-WLED device has been fabricated through Na2BaCa0.2Sr0.8(PO4)(2):0.03Eu(2+) blue phosphor mixed with commercial yellow phosphor (SrSi2O2N2:Eu2+) and red phosphor (Sr2Si5N8:Eu2+), which performs a color temperature of 4721 K with a high color rendering index of Ra = 91.9. In view of zero thermal quenching and favorable quantum efficiency, this new phosphor is a prospect candidate for blue phosphors in WLED application. Further, the work provides a new method and reference for the great enhancement of thermal stability and quantum efficiency of luminescence materials. (C) 2022 Elsevier B.V. All rights reserved.
作者机构：
[Qin, Feng; Zhou, Qian] College of Materials Science and Engineering, Hebei University of Engineering, Handan 056038, China;College of Mechanical and Electrical Engineering, Central South University of Forestry and Technology, Changsha 410004, China;Author to whom correspondence should be addressed.;[Guo, Pengcheng] College of Mechanical and Electrical Engineering, Central South University of Forestry and Technology, Changsha 410004, China<&wdkj&>Author to whom correspondence should be addressed.
通讯机构：
[Pengcheng Guo] C;College of Mechanical and Electrical Engineering, Central South University of Forestry and Technology, Changsha 410004, China<&wdkj&>Author to whom correspondence should be addressed.
通讯机构：
[Lijun Li] C;[Shaobing Wu] K;Key Laboratory of Optoelectronic Devices and Systems of Ministry of Education and Guangdong Province, College of Optoelectronic Engineering, Shenzhen University, Shenzhen, 518060, China<&wdkj&>College of Mechanical and Electrical Engineering, Central South University of Forestry and Technology, Changsha, 410004, China
摘要：
As one of the most important reactive oxygen species, hypochlorite plays an important role in maintaining human immunity. Herein, we reported a plasmonic near field assistant highly sensitive detection of hypochlorite by a Astrazon Brilliant Red 4G modified lanthanide co-doped core/shell upconversion probe. The Astrazon Brilliant Red 4G on the upconversion nanoparticles surface serves as a green emission quencher, and the emission can be recovered by the adding hypochlorite. The plasmonic nanoparticle on the interface can generate local nearfield and hot carrier, which can accelerate the reaction and finally improved the sensing performance. A detection of 12 ppm was achieved. This fluorescence sensing strategy based on the inorganic composite can be used in real time and stable detection of hypochlorite in bio tissue fluid or industrial waste water.
期刊：
Journal of Mechanical Design,2022年144(2):022001 ISSN：1050-0472
通讯作者：
Wang, Hu
作者机构：
[Li, Yu; Wang, Hu; Wang, Jiaquan] Hunan Univ, State Key Lab Adv Design & Mfg Vehicle Body, Changsha 410082, Hunan, Peoples R China.;[Li, Biyu] Zhuzhou CRRC Times Elect Co Ltd, Technol Ctr, Zhuzhou 412001, Hunan, Peoples R China.;[Li, Enying] Cent South Univ Forestry & Technol, Coll Mech & Elect Engn, Changsha 41004, Peoples R China.
通讯机构：
[Wang, Hu] H;Hunan Univ, State Key Lab Adv Design & Mfg Vehicle Body, Changsha 410082, Hunan, Peoples R China.
关键词：
approximation-based optimal design;data-driven design;machine learning;surrogate model
摘要：
The purpose of this study is to obtain a margin of safety for material and process parameters in sheet metal forming. Commonly applied forming criteria are difficult to comprehensively evaluate the forming quality directly. Therefore, an image-driven criterion is suggested for uncertainty parameter identification of sheet metal forming. In this way, more useful characteristics, material flow, and distributions of safe and crack regions, can be considered. Moreover, to improve the efficiency for obtaining sufficient statistics of Approximate Bayesian Computation (ABC), a manifold learning-assisted ABC uncertainty inverse framework is proposed. Based on the framework, the design parameters of two sheet metal forming problems, an air conditioning cover and an engine inner hood, are identified.
作者机构：
[Mo, Weinan; Li, Ling; Cao, Ying] Cent South Univ Forestry & Technol, Coll Mech & Elect Engn, Changsha 410004, Peoples R China.;[Mo, Weinan; Sun, Zhexing; Cao, Ying] Kunming Univ Sci & Technol, Fac Modern Agr Engn, Kunming 650500, Yunnan, Peoples R China.
通讯机构：
[Ling Li] C;College of Mechanical and Electrical Engineering, Central South University of Forestry and Technology, Changsha 410004, China<&wdkj&>Author to whom correspondence should be addressed.
摘要：
With the rise of mobile social networks, an increasing number of consumers are shopping through Internet platforms. The information asymmetry between consumers and producers has caused producers to misjudge the positioning of agricultural products in the market and damaged the interests of consumers. This imbalance between supply and demand is detrimental to the development of the agricultural market. Sentiment tendency analysis of after-sale reviews of agricultural products on the Internet could effectively help consumers evaluate the quality of agricultural products and help enterprises optimize and upgrade their products. Targeting problems such as non-standard expressions and sparse features in agricultural product reviews, this paper proposes a sentiment analysis algorithm based on an improved Bidirectional Encoder Representations from Transformers (BERT) model with symmetrical structure to obtain sentence-level feature vectors of agricultural product evaluations containing complete semantic information. Specifically, we propose a recognition method based on speech rules to identify the emotional tendencies of consumers when evaluating agricultural products and extract consumer demand for agricultural product attributes from online reviews. Our results showed that the F1 value of the trained model reached 89.86% on the test set, which is an increase of 7.05 compared with that of the original BERT model. The agricultural evaluation classification algorithm proposed in this paper could efficiently determine the emotion expressed by the text, which helps to further analyze network evaluation data, extract effective information, and realize the visualization of emotion.
期刊：
Structural and Multidisciplinary Optimization,2022年65(11):1-10 ISSN：1615-147X
通讯作者：
Daihui Liao
作者机构：
[Xie, Huichao] Cent South Univ Forestry & Technol, Coll Mat Sci & Engn, Changsha 410004, Peoples R China.;[Liao, Daihui; Li, Jinwen] Cent South Univ Forestry & Technol, Coll Mech & Elect Engn, Changsha 410004, Peoples R China.
通讯机构：
[Daihui Liao] C;College of Mechanical and Electrical Engineering, Central South University of Forestry and Technology, Changsha, People’s Republic of China
关键词：
Structural reliability analysis;Non-parameterized P-box;Linear program;Failure probability bounds
摘要：
The probability box (P-box) model is an effective quantification tool that can deal with aleatory and epistemic uncertainties and can generally be categorized into two classes, namely, parameterized P-box and non-parameterized P-box ones. This paper proposes a new structural reliability analysis method with the non-parameterized P-box uncertainty, through which bounds of the failure probability can be obtained efficiently. For the convenience of calculation, the reliability analysis problems are divided into the univariate and multivariate ones. Firstly, structural failure probability bound analysis for the univariate problem is converted into solving two linear programming models by discretizing the cumulative distribution function (CDF) of the P-box variable, which can be solved efficiently by the simplex algorithm. Secondly, an iterative technique is used to decompose the multivariate problem into a series of univariate problems, in which only one non-parameterized P-box's CDF is optimized and the remaining counterparts are fixed. Hence, the failure probability bounds can be obtained by solving a series of linear programming problems. Finally, the effectiveness of the proposed method is demonstrated by investigating three numerical examples.
摘要：
In this article, amplitude, and vibrational characteristics of a rotating fiber metal laminated microdisk are presented. The current microstructure is modeled as a flexible microdisk surrounded by the two-parameter viscoelastic foundation. The centrifugal and coriolis effects due to the rotation are considered. The strains and stresses can be determined via the third-order shear deformable theory. For accessing to size-effects, the nonlocal strain gradient theory is used. The boundary conditions are derived through governing equations of the laminated rotating microdisk using an energy method known as Hamilton's principle and finally are solved using a numerical method based generalized differential quadrature method.
作者机构：
[Si, Jiayong; Fan, Xiaoyi; Tang, Jiamin] Cent South Univ Forestry & Technol, Coll Mech & Elect Engn, Changsha 410004, Peoples R China.;[Cai, Gemei; Liu, Yijia; Li, Guihua] Cent South Univ, Sch Mat Sci & Engn, Changsha 410083, Peoples R China.
通讯机构：
[Jiayong Si] C;[Gemei Cai] S;College of Mechanical and Electrical Engineering, Central South University of Forestry and Technology, Changsha 410004, China<&wdkj&>School of Materials Science and Engineering, Central South University, Changsha 410083, China
摘要：
A series of single Ce3+ doped and Ce3+ and Tb3+ co-doped Na2BaCa(PO4)(2) (NBCP) phosphors was synthesized by conventional solid-stated reaction method. The crystal structure, luminescence properties, thermal stability and energy transfer were carefully investigated. Ce3+ is inferred to substitute the Ba2+ site in NBCP lattice. The color-tunable emission from blue to green is observed by adjusting Tb3+ concentration among NBCP:0.03Ce(3+),yTb(3+) phosphors. The energy transfer behavior from Ce3+ to Tb3+ ions is both illustrated by co-doped PL spectra and decay curves. The energy transfer efficiency is as high as 91.5%. The mechanism of energy transfer is resonance type of dipole-dipole transition. In this work, the optimal phosphor exhibits the excellent thermal stability which keeps at 94.9% of that initial value at room temperature when temperature reaches to 150 degrees C. The Ce3+ and Tb3+ co-doped NBCP phosphor is a promising candidate for the application in the general lighting and display fields. (c) 2021 Chinese Society of Rare Earths. Published by Elsevier B.V. All rights reserved.
通讯机构：
[Jiujiu Chen] S;State Key Laboratory of Advanced Design and Manufacturing for Vehicle Body, College of Mechanical and Vehicle Engineering, Hunan University, Changsha 410082, China
