摘要：
During the process of developing commercial chips, the phosphors with single broadband emission are indispensable. In this report, a new ternary phosphate phosphor Na3Ba2Ca(PO4)(3):Eu2+ has been successfully synthesized by the high-temperature solid-state reaction (HSSR) method, which shows broad emitting band in the range of 350-600 nm centered at 436 nm (FWHM similar to 72.3 nm). The crystal structure of the Na3Ba2Ca(PO4)(3) and Eu2+ doped Na3Ba2Ca(PO4)(3) were determined by the Rietveld method, indicating the trigonal system with P31c space group. The selective two-site occupancy tendency of Eu2+ ions at Ba1O(9) and Ca2O(8) sites in the matrix was comprehensively revealed according to the split peaks (433 nm and 469 nm) at 298 K and 11 K, computational validation and fluorescence lifetime analysis of photoluminescence spectrum. Impressively, the optimal Na3Ba2Ca(PO4)(3):0.02Eu(2+) phosphor exhibits appropriate spectrum resemblance (SR) indexes (58.5% and 72.2%), proper thermostability (78.6%) and excellent chromaticity stability (Delta x = 8.68 x 10(-6) and Delta y = 3.64 x 10(-5)). Besides, the phosphor prepared by HSSR owns the higher internal quantum efficiency of 62.1% in comparison with that synthesized by polymerizable complex (PC) method. The new phosphor can serve as a potential broadband and blue-emitting phosphor for the application of solid-state lighting and plant growth.
摘要：
The new dual-emitting and color tunable single phase of Na2BaSr(PO4)(2):0.03Eu(2+), xMn(2+) (NBSP:0.03Eu(2+), xMn(2+)) phosphor are successful prepared in this work. The phase purity and photoluminescence properties are investigated. Regarding to the coordination, valence and cation radius, the Eu2+ ions occupy the Sr2 and Sr3 site and Mn2+ ions occupy the Sr3 site. According to the photoluminescence (PL) spectra of NBSP:0.03Eu(2+), xMn(2+) (x = 0-0.09), the strong energy transfer (ET) between Eu2+ and Mn2+ exists in these phosphors. The strong ET efficiency from Eu2+ to Mn2+ is as high as 92%, while the ET mechanism of Eu2+ and Mn2+ is quadrupole-quadrupole interaction. Moreover, the CIE coordinate of Eu2+ and Mn2+ co-doped Na2BaSr(PO4)(2) phosphors can realize the color tunable emission from blue to cold white. The temperature dependent photoluminescence intensity of NBSP:0.03Eu(2+), 0.05Mn(2+) phosphor still keeps 75.8% of that initial intensity when the temperature is 150 degrees C. In summary, the NBSP:0.03Eu(2+), xMn(2+) phosphors have a promising application in white light LED.
摘要：
In this paper, the performance and emission characteristics of a diesel engine were investigated with varying ratios of tung oil-based biodiesel blends (B10, B20, and B50) and neat diesel under different operating conditions. The experimental results showed that the addition of biodiesel blends had different effects on engine power and torque depending on the blend ratio. B10 displayed a slight increase in power and torque, which increased by 1.9% and 6.6%. At the same time, B20 and B50 showed declines slightly. The fuel consumption rate increased slightly with an increasing percentage of biodiesel added. In general, all the blends exhibited significantly lower emissions of CO, NOX, HC, and smoke compared to neat diesel. B10 displayed the most notable reduction of CO emissions, with a 42.86% decrease at medium to high loads. NOX emissions of tung oil-based biodiesel blends were reduced at all load conditions except for B50. In addition, HC emissions were all reduced, especially for B20, which led to a 27.54% reduction at 50% load. Among all the tested blends, B50 showed the greatest decrease in smoke emissions of 38.05% compared to neat diesel at 2000 rpm. The research concluded that using biodiesel fuels from renewable resources, such as tung oil, presents a promising environmentally friendly alternative fuel option.
摘要：
Tomato disease control is an urgent requirement in the field of intellectual agriculture, and one of the keys to it is quantitative identification and precise segmentation of tomato leaf diseases. Some diseased areas on tomato leaves are tiny and may go unnoticed during segmentation. Blurred edge also makes the segmentation accuracy poor. Based on UNet, we propose an effective image-based tomato leaf disease segmentation method called Cross-layer Attention Fusion Mechanism combined with Multi-scale Convolution Module (MC-UNet). First, a Multi-scale Convolution Module is proposed. This module obtains multiscale information about tomato disease by employing 3 convolution kernels of different sizes, and it highlights the edge feature information of tomato disease using the Squeeze-and-Excitation Module. Second, a Cross-layer Attention Fusion Mechanism is proposed. This mechanism highlights tomato leaf disease locations via gating structure and fusion operation. Then, we employ SoftPool rather than MaxPool to retain valid information on tomato leaves. Finally, we use the SeLU function appropriately to avoid network neuron dropout. We compared MC-UNet to the existing segmentation network on our self-built tomato leaf disease segmentation dataset and MC-UNet achieved 91.32% accuracy and 6.67M parameters. Our method achieves good results for tomato leaf disease segmentation, which demonstrates the effectiveness of the proposed methods.
摘要：
This study proposes a piecewise high-order differential interpolation method with rapid convergence to construct an ultrasmooth high-speed cam profile. The proposed method enables a solution to be realized to manipulate the dynamic performance of a cam profile with C3 continuity during the whole working process. The reconstruction characteristics of the cam profile by the high-order differential interpolation method are compared with the most commonly used linear profile interpolation strategy. Thus, the proposed piecewise high-order differential interpolation method is validated as a feasible and effective methodology to design and reconstruct an ultrasmooth cam profile.
摘要：
The ever-increasing demands for miniature integrated optics, mechanics, electronics, and biofluidics have generated great interest in high-performance glass components featuring functional micro/nanostructures. Focusing on micro/nanostructuring of optical glass, many landmark processing techniques have been developed. However, due to notable differences in the capabilities of these techniques, researchers often encounter difficulties in selecting the appropriate glass feedstock or determining the optimal/complementary strategy for achieving a specific production task with desired resolution, accuracy, and efficiency. To shed light on potential solutions, this paper presents a state-of-the-art review that covers subtractive, additive, and formative manufacturing of functional micro/nanostructures using the broadest forms of glass feedstocks (including blocks, powders, and precursors). Initiating with a complete technical classification, the fundamentals, developments, and recent breakthroughs in micro/nanostructuring of glass are comprehensively outlined. Subsequently, the essential features (including spatial resolution, surface finish, accuracy, and efficiency) of the collected glass micro/nanomanufacturing techniques are comparatively evaluated, followed by detailed discussions of their capabilities and current challenges. Finally, future prospects are summarized to highlight potential opportunities and directions in glass micro/nanofabrication. This review will offer a panoramic guideline to the selection and innovation of glass materials and processing strategies for application-oriented precision and efficient manufacturing of diverse glass-based functional micro/nanostructures.
期刊：
Separation and Purification Technology,2023年306:122521 ISSN：1383-5866
通讯作者：
Rongkui Su<&wdkj&>Liqing Li
作者机构：
[Xu, Wenjun; Ma, Xiancheng] Cent South Univ Forestry & Technol, Coll Mech & Elect Engn, Changsha 410083, Hunan, Peoples R China.;[Li, Liqing; Zeng, Zheng] Cent South Univ, Sch Energy Sci & Engn, Changsha 410083, Hunan, Peoples R China.;[Su, Rongkui; Wang, Hanqing] Cent South Univ Forestry & Technol, Coll Environm Sci & Engn, Changsha 410083, Hunan, Peoples R China.;[Shao, Lishu] Cent South Univ Forestry & Technol, Sch Mat Sci & Engn, Changsha, Peoples R China.
通讯机构：
[Rongkui Su] C;[Liqing Li] S;College of Environmental Science and Engineering, Central South University of Forestry and Technology, Changsha 410083, Hunan, China<&wdkj&>School of Energy Science and Engineering, Central South University, Changsha 410083, Hunan, China
摘要：
Porous carbon is one of the important CO2 adsorbents being developed at present. However, interpreting the potential mechanism of CO2 adsorption by porous carbon is still challenging due to their various functional groups, different structural characteristics and different adsorption conditions (temperature and pressure) during CO2 adsorption. Here, this study firstly applied machine learning to study the effects of pore structure, chemical properties, and adsorption conditions on CO2 adsorption performance based on 1594 CO2 adsorption datasets, and to predict CO2 adsorption capacity. The results show that the R2 of the random forest (RF) model is above 0.97 on the training and test data, which has good prediction performance. According to RF analysis results, the nitrogen groups of porous carbon have the greatest impact on CO2 capture at 0–0.15 bar, while ultra-micropores have the greatest impact on CO2 capture at 0.15–1 bar. Subsequently, we prepared three kinds of porous carbons with different pore structures and functional groups, and carried out CO2 adsorption isotherm tests. The results were consistent with the results of machine learning. However, the above results hardly reveal the effect of functional group type and pore size on CO2 capture. Finally, the relative importance of pore size and functional group on CO2 adsorption under different pressures was calculated by molecular simulation, and the mechanism of CO2 adsorption by a single pore size and functional group species was revealed. The results based on the aforementioned machine learning, experimental data and molecular simulation are of great significance for predicting gas adsorption and guiding the development of the carbon-based adsorbents.
摘要：
The BP neural network can effectively improve the accuracy of state of charge (SOC) estimation by the EKF algorithm. However, the BP neural network is strongly influenced by the initial weights and thresholds, which limits its application in the SOC estimation. To improve the current defects of the BP neural network for better application to the SOC estimation, this paper proposes a method to improve the performance of the EKF algo-rithm for SOC estimation by optimizing the BP neural network using the tuna swarm optimization (TSO) al-gorithm. Based on the constructed first-order RC battery model, the optimized BP neural network was trained offline and used to compensate the SOC estimation error of the EKF algorithm online. The superiority of the proposed algorithm for SOC applications was demonstrated by simulation experiments under both dynamic stress test (DST) and Beijing dynamic stress test (BJDST) operating conditions. In addition, comparative ex-periments with existing hybrid algorithms were conducted. The simulation results show that compared with the EKF algorithm and the traditional BP-EKF algorithm, the proposed algorithm has better estimation accuracy and convergence for SOC and can track the SOC variation well. Compared with the conventional BP-EKF algorithm, the RMSE and MAE values of the proposed algorithm decreased respectively by 35.7 % and 37 % under DST, and respectively by 38.4 % and 43.3 % under BJDST. Besides, the proposed algorithm has better performance than other hybrid algorithms.
作者机构：
[Luo, Qiang; Guo, Xin; Deng, Qianwang; Deng, QW] Hunan Univ, State Key Lab Adv Design & Mfg Vehicle Body, Changsha 410082, Peoples R China.;[Gong, Guiliang] Cent South Univ Forestry & Technol, Dept Mech & Elect Engn, Changsha 410004, Peoples R China.;[Chen, Liangwu; Zhao, Xinhe] China Railway Engn Equipment Grp Tech Serv Co Ltd, Zhengzhou 450003, Peoples R China.
通讯机构：
[Deng, QW ] H;Hunan Univ, State Key Lab Adv Design & Mfg Vehicle Body, Changsha 410082, Peoples R China.
关键词：
Distributed assembly hybrid flowshop;scheduling;Transportation resource;Early assembly;MOEA/D;Problem-based local search
摘要：
In the distributed assembly flowshop scheduling problem (DAFSP), the transportation resources between the production and assembly stages are rarely scheduled. However, for production managers, the transportation stage is important as it directly influences the cooperation between the production and assembly phases. Hence, in this study, a critical variant of the DAFSP, called the distributed assembly hybrid flowshop scheduling problem with transportation resource scheduling (DAHFSPT), is evaluated. DAHFSPT considers several vehicles for component delivery, and the early assembly is allowed in the assembly site. A mixed-integer linear programming model of the problem is developed to minimize the makespan and total energy consumption simultaneously. To solve the problem, an improved multi-objective evolutionary algorithm based on decomposition (IMOEA/D) is proposed. In the IMOEA/D, a well-designed encoding method, and eight heuristics decoding methods are embedded into the initialization operator to generate a high-quality initial population. A problem-based local search operator is presented to enhance the performance of the algorithm and accelerate its convergence. In addition, an elimination-reinitialization operator is designed to avoid optimal local solutions. A total of 200 instances based on classical benchmarks are formulated to verify the effectiveness of each improvement component in the IMOEA/D. Comprehensive experiments indicate that the IMOEA/D outperforms five well-known multi-objective algorithms concerning solution quality and distribution in solving the DAHFSPT.
通讯机构：
[Wan, YD ] C;Cent South Univ Forestry & Technol, Coll Mech & Elect Engn, Changsha 410004, Peoples R China.
关键词：
evaporative cooling;solar energy;mathematical models;hybrid system;sustainable development
摘要：
Recent advancements in single-stage evaporative cooling (EC) have showcased their effectiveness as an energy-efficient and sustainable air-conditioning (AC) solution. However, several challenges hinder the widespread adoption of EC in various applications. These challenges include climate sensitivity, substantial spatial requirements, and limitations in achieving desired output temperatures. To address these concerns, there has been a growing focus on integrating EC with solar energy (SE) systems. With traditional energy resources being depleted, the use of SE has gained prominence as a sustainable solution to meet future energy demands while mitigating environmental pollution. This paper presents a comprehensive review of hybrid EC-SE systems, aiming to elucidate the potential synergies, benefits, and challenges associated with this integration. The review explores the principles and mathematical approaches of various configurations of EC systems to assess their compatibility with SE sources. Furthermore, the review delves into the mathematical model of SE, encompassing both solar power generation and thermal collectors, with the aim of integrating it into the EC model. It delves into key aspects of energy consumption and performance, showcasing advancements in achieving higher efficiency and enhanced cooling capacity through the hybrid systems. Additionally, the review highlights research gaps in the existing literature, emphasizing the need for further exploration in this interdisciplinary field. In conclusion, this paper offers valuable insights into the potential of EC-SE systems to address energy and cooling requirements while promoting sustainable development.
作者机构：
[Huang, Longhui; Luo, Hong; Dong, Xinran; Gao, Jinghui] Cent South Univ Forestry & Technol, Coll Mech & Elect Engn, Changsha 410004, Peoples R China.;[Song, Yuxin] City Univ Hong Kong, Dept Mech Engn, Kowloon, Hong Kong 999077, Peoples R China.;[Wang, Cong; Duan, Ji-an] Cent South Univ, Coll Mech & Elect Engn, State Key Lab Precis Mfg Extreme Serv Performance, Changsha 410083, Peoples R China.
通讯机构：
[Dong, XR ] C;Cent South Univ Forestry & Technol, Coll Mech & Elect Engn, Changsha 410004, Peoples R China.
摘要：
Fog collection holds promise for addressing water shortage. However, the conventional fabrication of fog collection devices, normally chemical methods, suffers many challenges, such as complicated preparation and environmental issues. Herein, we proposed a green fabrication strategy to construct superhydrophobic/hydrophilic surfaces on the brass substrate via the combination of laser fabrication and heat treatment. The wettability of brass is directly dictated by the laser process parameters. The different superhydrophobic/hydrophilic hybrid pattern surface with a rectangular/triangular array was designed for an optimal fog collection performance. The maximum water collection efficiency of the prepared surface is measured up to 427.36 mg h(-1) cm(-2), which is 97% higher than that of the control sample. Furthermore, the surface can be folded into different forms to realize a flexible collector. We envision that our work provides a green fabrication strategy to construct a superwetting surface for highly efficient fog collection.
摘要：
This study explores the impact of shot peening residual compressive stress on repairing surface cracks in the 7075-T651 aluminum alloy. Two models were developed for crack repair via shot peening and fatigue test finite element modeling. A multi-step numerical simulation introduced shot peening-induced residual stress into the fatigue test model, and subsequent simulations analyzed the crack repair mechanism. The research results indicate that increasing pressure and projectile size improve repair effectiveness, but higher pressure causes material damage, and larger projectiles decrease fatigue life. Crack repair effectiveness decreased with higher loading levels, more significantly at higher loads. Experimental and simulation results matched well, validating the simulation model for shot peen repair processes and offering optimization possibilities.
期刊：
JOURNAL OF AGRICULTURAL ENGINEERING,2023年54(2) ISSN：1974-7071
通讯作者：
Li, LJ
作者机构：
[Fan, Ziyan; Li, Lijun; Gao, Zicheng] Coll Mech & Elect Engn, Cent South Univ Forestry & Technol, Changsha, Peoples R China.;[Li, Lijun] Cent South Univ Forestry & Technol, Coll Mech & Elect Engn, Changsha 410000, Peoples R China.
通讯机构：
[Li, LJ ] C;Cent South Univ Forestry & Technol, Coll Mech & Elect Engn, Changsha 410000, Peoples R China.
关键词：
camellia fruit picking machine;vibration frequency PID control;fuzzy wavelet neural network
摘要：
Due to the growth characteristics of the flowers and fruits of camellia in the same period, the vibrating camellia fruit picking machine needs to ensure the constant rotational speed of the vibrating hydraulic motor when the picking mechanism is operating, to achieve a constant vibration frequency, to ensure that the camellia fruit can smoothly fall off the branches through vibration. In contrast, the camellia fruit does not fall off. In this regard, this paper deduced the state space equation of the camellia fruit picking machine's valve-controlled vibrating hydraulic motor system and designed a fuzzy wavelet neural network PID controller (FWNN PID controller) based on the traditional incremental PID control principle. Then the designed vibration picking manipulator control system was simulated under no-load, 5 s load conditions, and load start conditions with MATLAB/Simulink, a general PID controller and a fuzzy RBF neural network PID controller (FRBFNN PID controller) were used to contrast with it. The results show that the general PID controller has a slow response speed and poor robustness, while fuzzy neural network PID controllers (including FWNN PID controller and FRBFNN PID controller) have a fast response speed and strong robustness, which can well meet the requirements of a specific vibration frequency. Finally, a field test was carried out. The results show that the FWNN PID control is better than the FRBFNN PID control. Furthermore, the FWNN PID controller obviously reduced the drop rate of camellia flowers within 6% while ensuring the picking efficiency above 90%, which can well meet the needs of the camellia fruit picking operation.
作者：
Huang, Shuai;Hu, Youmin;Jin, Wenwen;Huang, Dan
期刊：
LWT,2023年185:115139 ISSN：0023-6438
通讯作者：
Huang, D
作者机构：
[Huang, Shuai; Huang, Dan] Cent South Univ Forestry & Technol, Sch Mech & Elect Engn, Changsha 410000, Peoples R China.;[Hu, Youmin] Huazhong Univ Sci & Technol, Sch Mech Sci & Engn, Wuhan 430074, Peoples R China.;[Jin, Wenwen] Huazhong Univ Sci & Technol, Coll Life Sci & Technol, Wuhan 430074, Peoples R China.;[Huang, Dan] Cent South Univ Forestry & Technol, Sch Mech & Elect Engn, 589 Shaoshan South Rd, Changsha 410000, Peoples R China.
通讯机构：
[Huang, D ] C;Cent South Univ Forestry & Technol, Sch Mech & Elect Engn, 589 Shaoshan South Rd, Changsha 410000, Peoples R China.
关键词：
Bleaching process;Camellia oil;Modeling;Surrogate model
摘要：
The objective of this article is to study the effect of bleaching conditions on the quality of camellia oil. To achieve this goal, the relationship between bleaching conditions (e.g., heating temperature, stirring speed, stirring time, and adsorbent content) and quality indexes are established using four surrogate models. The performance of different surrogate models is then compared, and the best one is chosen to analyze the influence of process parameters on quality. Additionally, the global sensitive analysis (GSA) is conducted to determine the relative importance of the four process parameters on oil quality. The results show: the RSM yields the best modeling accuracy for bleaching rate (BR), while SVR performs best for peroxide value (PV); Activated clay is the most important factor affecting both BR and PV, followed by heating temperature, stirring time, and stirring speed; The BR of 96.33% and PV of 0.03 meq/kg are obtained under the optimum bleaching conditions (temperature of 80 degrees C, stirring time of 10 rmp, stirring speed of 60 rpm, and adsorbent content of 7 g/hg), which is validated by experiment under the same conditions.
