通讯机构：
[Dan Huang] D;Department of Mechanical and Electrical Engineering, Central South University of Forestry and Technology, Changsha, China
关键词：
color change;drying rate;energy consumption;mathematical model;ultrasonic pretreatment
摘要：
The ultrasound‐assisted hot air drying characteristics of Phyllanthus emblica was investigated in this paper. Appropriate ultrasonic time and power can improve the drying rate and rehydration rate of Phyllanthus emblica, and reduce the color difference and energy consumption of Phyllanthus emblica. Abstract The ultrasound‐assisted hot air drying characteristics of Phyllanthus emblica was investigated in this paper. The effects of hot air temperature (60°C, 65°C, 70°C, and 75°C), ultrasonic pretreatment time (2, 4, 6, and 8 min), and ultrasonic power (200, 250, 300, and 350 W) on the drying rate, energy consumption, color change, and rehydration rate were evaluated and compared. It was found that the drying rate of Phyllanthus emblica increased with the hot air temperature. The drying time of Phyllanthus emblica with ultrasonic pretreatment was reduced by 10.0%, 25.0%, 21.4%, and 9.0% at 60°C, 65°C, 70°C, and 75°C, respectively. However, the hot air drying was not proportionally promoted by the increase of ultrasonic power or the extension of pretreatment time. Only an appropriate ultrasonic power or pretreatment time can not only improve the drying rate and rehydration rate, but also reduce the energy consumption and the total color change of the dried samples. A new drying model that considered the influences of hot air temperature, pretreatment time, and ultrasonic power was developed to fit the drying process. The results showed that the new model can accurately predict the hot air drying process of Phyllanthus emblica with and without ultrasonic pretreatment. Practical applications Phyllanthus emblica contains a variety of nutrients and has various biological activities. However, the harvest period and shelf life of Phyllanthus emblica is very short, and the fruit is prone to mildrew and browning after picking, which in turn leads to the loss of its nutritional and economical value. Thus, for the long‐term preservation of Phyllanthus emblica, drying techniques are needed. In the food industry, hot air drying is widely used due to its low cost and easy operation; however, it also has some disadvantages such as long drying time, the oxygen‐rich drying environment. These shortcomings lead to a low quality of dried materials. Ultrasonic pretreatment before hot air drying can improve drying efficiency without adversely affecting the drying quality of the material. In recent years, ultrasonic pretreatment before food drying has become a research hotspot.
摘要：
Green and low-cost biomass-based porous carbon adsorbents have a good prospect for the removal of some environmental pollutants. Here, sodium lignosulphonate, chitosan, and activator were firstly combined into wet gel microbeads through in situ self-assembly method, and then derived the novel porous carbon adsorption materials (LC-Cs) by freeze-drying and one-step activation carbonization. The results showed that LC-Cs had large specific surface areas (892.4∼1307.8 m2/g), high microporosity (87.4∼89.2%), and rich nitrogen content (3.01∼4.92%), and these structural parameters showed good linear dependence with the dosage ratio of lignin to chitosan. Next, LC-Cs carbon showed efficient CO2 capture (173.9–215.2 mg/g) and high CO2/N2 selectivity (up to IAST:145.9, Henry’s law: 23.5), specially, the relationships between the CO2 capture and the structural parameters were investigated in detail, and also performed DFT calculation. In addition, LC-C22 had the maximum adsorption capacity of p-nitrophenol (PNP) as 592.8 mg/g, and the adsorption isotherms and kinetic study indicated that they belonged to the multilayer adsorption on the heterogeneous surfaces, and the chemical adsorption played the dominated roles, and then further studied the adsorption mechanism by characterization techniques. This work provided a green and facile strategy for preparing structurally controllable N-doped porous carbon materials, as well as offered good potential adsorbents for PNP removal and CO2 capture.
作者机构：
[Wang, Hu; Deng, Xinjian] Hunan Univ, State Key Lab Adv Design & Mfg Vehicle Body, Changsha 410082, Peoples R China.;[Li, Enying] Cent South Univ Forestry & Technol, Coll Mech & Elect Engn, Changsha 410004, Peoples R China.
通讯机构：
[Enying Li] C;College of Mechanical & Electrical Engineering, Central South University of Forestry and Technology, Changsha 410004, China<&wdkj&>Author to whom correspondence should be addressed.
摘要：
For the multi-objective design of heat sinks, several evolutionary algorithms usually require many iterations to converge, which is computationally expensive. Variable-fidelity multi-objective (VFO) methods were suggested to improve the efficiency of evolutionary algorithms. However, multi-objective problems are seldom optimized using VFO. Therefore, a variable-fidelity evolutionary method (VFMEM) was suggested. Similar to other variable-fidelity algorithms, VFMEM solves a high-fidelity model using a low-fidelity model. Compared with other algorithms, the distinctive characteristic of VFMEM is its application in multi-objective optimization. First, the suggested method uses a low-fidelity model to locate the region where the global optimal solution might be found. Sequentially, both high- and low-fidelity models can be integrated to find the real global optimal solution. Circulation distance elimination (CDE) was suggested to uniformly obtain the PF. To evaluate the feasibility of VFMEM, two classical benchmark functions were tested. Compared with the widely used multi-objective particle swarm optimization (MOPSO), the efficiency of VFMEM was significantly improved and the Pareto frontier (PFs) could also be obtained. To evaluate the algorithm's feasibility, a polygonal pin fin heat sink (PFHS) design was carried out using VFMEM. Compared with the initial design, the results showed that the mass, base temperature, and temperature difference of the designed optimum heat sink were decreased 5.5%, 18.5%, and 62.0%, respectively. More importantly, if the design was completed directly by MOPSO, the computational cost of the entire optimization procedure would be significantly increased.
摘要：
Previous research on the integrated scheduling problems generally considers the production and distribution stages, but ignores the arrangement of on-hand inventory saved in the warehouse. However, the overall optimal solution to meet customer demands must require a high degree of coordination between the production, inventory and distribution stages. Encouraged by this, we study a new production-inventory-distribution integrated scheduling problem, in which the production plan in a homogeneous flowshop environment, allocation plan of on-hand inventory and distribution decision of three-party logistics provider, are considered simultaneously. A mixed integer linear programming model with the goal of minimizing total earliness/tardiness penalty costs and total energy consumption is built for the problem. A modified NSGA-II (abbreviated as MNSGA) is proposed to solve the problem. In the MNSGA, a well-tailored three-layer encoding method is presented for the chromosome representation. The adaptive crossover and mutation operators are developed for a good global search. In addition, an objective-oriented local search operator is designed to improve the local exploitation ability. The superiority of the proposed MNSGA is verified by comparing four popular multi-objective optimization algorithms based on 540 benchmark instances. Furthermore, the proposed integration mode is demonstrated to be effective by comparing it with several sequential scheduling methods commonly used in actual production.
作者机构：
[Zhou, Jinxing] School of Soil and Water Conservation, Beijing Forestry University, Beijing, 100083, PR China;[Tan, Mengjiao; Qin, Xiaoli; Li, Hui] State Key Laboratory of Utilization of Woody Oil Resource, Hunan Academy of Forestry, Changsha, 410004, PR China;[Zhang, Liqiang] College of Mechanical and Electrical Engineering, Central South University of Forestry and Technology, Changsha, Hunan, 410004, PR China;Hunan Xinheng Environmental Technology Co., LTD, Changsha, Hunan, 410004, PR China;[Huang, Zhongliang] School of Soil and Water Conservation, Beijing Forestry University, Beijing, 100083, PR China<&wdkj&>State Key Laboratory of Utilization of Woody Oil Resource, Hunan Academy of Forestry, Changsha, 410004, PR China
通讯机构：
[Mengjiao Tan; Hui Li] S;State Key Laboratory of Utilization of Woody Oil Resource, Hunan Academy of Forestry, Changsha, 410004, PR China
摘要：
Background: On-site and rapid detection of glucose level in foods is important for monitoring and control glucose intake. Methods: Magnetic and N-doped nanofibrous carbon microspheres (Fe@NCMs) with hierarchical porosity were designed as a novel nanozyme (Fe@NCMzyme), and the catalytic mechanism was investigated via the density functional theory (DFT) calculation. Therefore, Fe@NCMzyme sensor and point-of-care testing (POCT) platform were developed for glucose detection in food samples. Significant findings: Fe@NCMzyme showed 3D porous structure, a larger surface area, and N-doped carbon material properties, resulting in an enhanced peroxidase (POD)-like activity. In Fe@NCMzyme, Fe3O4 nanoparticles (FeNPs) act as catalytic centers and N-doped carbon nanofibers could be used as substrate binding sites. DFT results revealed that Fe-induced Fenton-like reaction was the main catalytic mechanism. The low detection limit and linear range of Fe@NCMzyme sensor was 0.247 mu M and 1-900 mu M, respectively. The excellent recovery ration in spiked food samples was 85.0 %-110.0 %. The applicability of Fe@NCMzyme sensor for glucose detection was verified by the commercial Glucometer. Furthermore, Fe@NCMzyme POCT platform was established and a linear detection range (10-900 mu M) was obtained with low detection limit (3.125 mu M). Importantly, Fe@NCMzyme POCT platform was realized visual, on-site, and rapid detection of glucose in food samples.
关键词：
valley topological refraction;edge state;elastic wave;phononic crystals
摘要：
Valley topological refraction material (TRM) of elastic wave and its direction signal transmittance with robustness against structural disturbance is crucial for various applications such as communication, navigation and detection devices for medical and industrial purpose. However, the existing TRM is limited by the single topological band, which obviously hinders the exploration of the multi-band topological ultrasonic devices to guarantee its efficiency and stability. Here, we demonstrate the dual-band valley TRM for elastic waves, in which the valley edge states and their robustness are investigated. Furthermore, the topological refractions of the valley edge states from the interface into the free space at zigzag termination in two frequency bands are explored, where the mode conversion of the bulk elastic wave occurs at interface termination. Interestingly, the full mode conversion from longitudinal to transverse waves is revealed in the low frequency band while the non-full mode conversion between the longitudinal and transverse takes place in the high frequency band. The researched dual-band elastic TRM could facilitate the potential applications in multi-band and multi-directional devices.
摘要：
Previous reports have shown that it is difficult to improve the methanol adsorption performance of nitrogen and oxygen groups due to their low polarity. Here, we first prepared porous carbon with a high specific surface area and large pore volume using benzimidazole as a carbon precursor and KOH as an activating agent. Then, we improved the surface polarity of the porous carbon by doping with Lithium (Li) to enhance the methanol adsorption performance. The results showed that the methanol adsorption capacity of Li-doped porous carbon reached 35.4 mmol g(-1), which increased by 57% compared to undoped porous carbon. Molecular simulation results showed that Li doping not only improved the methanol adsorption performance at low pressure, but also at relatively high pressure. This is mainly because Li-modified porous carbon has higher surface polarity than nitrogen and oxygen-modified surfaces, which can generate stronger electrostatic interactions. Furthermore, through density functional theory (DFT) calculations, we determined the adsorption energy, adsorption distance, and charge transfer between Li atom and methanol. Our results demonstrate that Li doping enhances the adsorption energy, reduces the adsorption distance, and increases the charge transfer in porous carbon. The mechanism of methanol adsorption by Li groups was revealed through experimental and theoretical calculations, providing a theoretical basis for the design and preparation of methanol adsorbents.
作者机构：
[Chong F.] School of Physics and New Energy, Xuzhou University of Technology, Xuzhou, 221000, China;[廖凯] College of Mechanical and Electrical Engineering, Central South University of Forestry and Technology, Changsha, 410004, China
通讯机构：
[Chong, F.] S;School of Physics and New Energy, China
期刊：
Structural and Multidisciplinary Optimization,2023年66(12):1-12 ISSN：1615-147X
通讯作者：
Liao, DH
作者机构：
[Hu, Hao; Xie, Huichao] Cent South Univ Forestry & Technol, Coll Mat Sci & Engn, Changsha 410004, Peoples R China.;[Liao, DH; Liao, Daihui; Li, Jinwen] Cent South Univ Forestry & Technol, Coll Mech & Elect Engn, Changsha 410004, Peoples R China.;[Li, Jinwen] BYD Auto Ind Co Ltd, Auto Engn Res Inst, Shenzhen 518118, Peoples R China.;[Liu, Haibo] Hunan Univ Sci & Technol, Hunan Prov Key Lab Hlth Maintenance Mech Equipment, Xiangtan 411201, Peoples R China.
通讯机构：
[Liao, DH ] C;Cent South Univ Forestry & Technol, Coll Mech & Elect Engn, Changsha 410004, Peoples R China.
关键词：
Uncertainty propagation;CDF bounds;Non-parameterized P-box;Maximum entropy estimation;Dimension-reduction integral
摘要：
The purpose of the non-parameterized P-box uncertainty propagation analysis is to calculate the cumulative distribution function (CDF) bounds of the response function based on the CDF bounds of the input parameters for a system. Generally, the uncertainty propagation analysis of non-parameterized P-box involves a double-layer nested analysis problem, which leads to excessive and unacceptable computational burden. Therefore, an efficient uncertainty propagation analysis method based on dimension-reduction integral is proposed for the problem with non-parameterized P-box parameters to obtain bounds of the CDF for the response function. Firstly, determining the CDF upper and lower bounds of the response function is transformed to computing the CDFs for two auxiliary response functions. Secondly, the origin moments of the above auxiliary response functions are calculated using the dimension-reduction integral method. Thirdly, using maximum entropy method, the CDFs of the auxiliary response functions are obtained with the origin moments, that is, the CDF bounds of the response function. Finally, three examples are investigated to illustrate the effectiveness of the proposed method.
