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.
期刊：
Expert Systems with Applications,2023年224:119840 ISSN：0957-4174
通讯作者：
Guiliang Gong
作者机构：
[Gong, Guiliang; Li, Xiaoqiang; Zhang, Liqiang; Zhu, Kaikai; Huang, Dan] Cent South Univ Forestry & Technol, Dept Mech & Elect Engn, Changsha 410004, Peoples R China.;[Gong, Guiliang; Luo, Qiang] Hunan Univ, State Key Lab Adv Design & Mfg Vehicle Body, Changsha 410082, Peoples R China.;[Peng, Ningtao] Cent South Univ, Dept Mech & Elect Engn, Changsha 410083, Peoples R China.
通讯机构：
[Guiliang Gong] D;Department of Mechanical and Electrical Engineering, Central South University of Forestry and Technology, Changsha 410004, China<&wdkj&>State Key Laboratory of Advanced Design and Manufacturing for Vehicle Body, Hunan University, Changsha 410082, China
通讯机构：
[Liqiang Zhang] C;College of Mechanical and Electrical Engineering, Central South University of Forestry and Technology, Changsha, People’s Republic of China
摘要：
Warm compaction technology is an eco-friendly method to improve the added value of poplar. In this work, the wood powder was compacted in the mold between 120 degrees C to 200 degrees C, at 80 MPa for 30 min. The color change, chemical properties, and mechanical properties were evaluated. The color of the formed compaction darkened uniformly. The CIE lightness color coordinate (L*) and chroma coordinates a* and b* decreased with the increase of forming temperature. Fourier infrared spectral analysis showed degradation of carbohydrates, along with the formation of a new chemical structure of darker color. Mechanical properties including modulus of rupture (MOR) and modulus of elasticity (MOE) of compacted wood increased initially and then decreased. These results provide a reference for the surface color control of thermally forming materials.
摘要：
For modeling solidification process of casting accurately, a reliable heat transfer boundary condition data is required. In this paper, an inverse conduction model was established to determine the heat flux and heat transfer coefficient at the metal-sand mold interface for cylindrical casting in the lost foam process. The numerically calculated temperature was compared with analytic solution and simulation solution obtained by commercial software ProCAST to investigate the accuracy of heat conduction model. The instantaneous cast and sand mold temperatures were measured experimentally and these values were used to determine the interfacial heat transfer coefficient (IHTC). The IHTC values during lost foam casting were shown to vary from 20 to 800 W m(-2) K-1. Additionally, the characteristics of the time-varying IHTC have also been discussed in this study.
通讯机构：
[Li, Luoxing] H;Hunan Univ, State Key Lab Adv Design & Mfg Vehicle Body, Changsha 410082, Hunan, Peoples R China.
关键词：
Aluminum alloy;Interfacial heat transfer;Nucleation site density;Spray pressure;Spray quenching;Surface roughness
摘要：
The heat flux (q) and heat transfer coefficient (h) at the interface between hot aluminum surface and spray water were determined by using an inverse heat conduction method. Good agreements between numerically calculated temperatures with the inverse identified h and experimentally measurements demonstrate that the method is valid for solving the q and h of spray quenching process. The estimated heat flux consists of three main stages of transition boiling, nucleate boiling and single-phase cooling. The results show that both the heat flux and heat transfer coefficient increase with the increasing of spray pressure. When the surface temperature is lower than 170 °C, the q, h and the maximum heat transfer coefficient (hmax) decrease and then increase as surface roughness increases. However, when the surface temperature is higher than 170 °C, the influence of surface is insignificant. This phenomenon may be attributed to the variation of nucleation site density with surface roughness.
期刊：
International Journal of Microstructure and Materials Properties,2013年8(4-5):325-332 ISSN：1741-8410
通讯作者：
Zeng, H.(zonghong78@live.cn)
作者机构：
[Zhang, Liqiang] College of Mechanical and Electrical Engineering, Central South University of Forestry and Technology, Changsha, Hunan, 410004, China;[Zeng, Hong] Advance Technology and Materials Co., Ltd., China Iron and Steel Research Institute Group, Beijing 100081, China
通讯机构：
Advance Technology and Materials Co., Ltd., China Iron and Steel Research Institute Group, China
期刊：
Heat and Mass Transfer,2013年49(8):1071-1080 ISSN：0947-7411
通讯作者：
Zhang, Liqiang
作者机构：
[Zhang, Liqiang] Cent South Univ Forestry & Technol, Coll Mech & Elect Engn, Changsha 410004, Hunan, Peoples R China.;[Zhang, Liqiang; Li, Luoxing] Hunan Univ, State Key Lab Adv Design & Mfg Vehicle Body, Changsha 410082, Hunan, Peoples R China.
通讯机构：
[Zhang, Liqiang] C;Cent South Univ Forestry & Technol, Coll Mech & Elect Engn, Changsha 410004, Hunan, Peoples R China.
关键词：
Heat Flux;Heat Conduction Model;Interfacial Heat Transfer Coefficient;Inverse Algorithm;Tolerance Criterion
摘要：
The present work focuses on the determination of interfacial heat transfer coefficients (IHTCs) between the casting and metal chill during casting solidification. The proposed method is established based on the least-squares technique and sequential function specification method and can be applied to calculate heat fluxes and IHTCs for other alloys. The accuracy and stability of the method has been investigated by using a typical profile of heat fluxes simulating the practical conditions of casting solidification. In the test process, the effects of various calculation parameters in the inverse algorithm are also analyzed. Moreover, numerically calculated and experimental results are compared by applying the determined IHTCs into the forward heat conduction model with the same boundary conditions. The results show that the numerically calculated temperatures are in good agreement with those measured experimentally. This confirms that the proposed method is a feasible and effective tool for determination of the casting-mold IHTCs.
