Characterizing elastic constants of anisotropic materials by spherical indentation method
作者：
Liao, Yanguo;Xie, Shuibo
期刊：
Current Applied Physics ,2023年53:9-18 ISSN：1567-1739
通讯作者：
Xie, SB
作者机构：
[Xie, Shuibo; Liao, Yanguo] Univ South China, Sch Resource Environm & Safety Engn, Hengyang 421001, Peoples R China.;[Liao, Yanguo] Univ South China, Sch Math & Phys, Hengyang 421001, Peoples R China.;[Xie, Shuibo] Univ South China, Sch Civil Engn, Hengyang 421001, Peoples R China.
通讯机构：
[Xie, SB ] U;Univ South China, Sch Civil Engn, Hengyang 421001, Peoples R China.
关键词：
Elastic parameters /constants;Finite element (FE);Indentation modulus;Spherical indentation;Three dimensional (3D);Transversely isotropic materials
摘要：
By the theoretical analysis and the finite element (FE) method, a new model for measuring the elastic constants of transversely isotropic materials has been proposed from spherical indentation. A theoretical analysis of the spherical indentation modulus for the materials is presented. Extensive spherical indentation tests were implemented by three dimensional (3D) FE simulations. By fitting the simulation results, the analytical relationship correlating the elastic parameters with the indentation moduli at three different indentation orientation angles (0°, 45°, and 90°) was set up. The effectiveness of the proposed method was examined by a series of numerical indentation experiments. It is found that the calculated values by the proposed method are well consistent with the input elastic parameters. The sensitivity of the calculated elastic parameters to the experimental data was analyzed. Simultaneously, this method was applied to carbon fiber materials. The results calculated by the method proposed in this paper were compared with results obtained by the theoretical model and experimental measurement to verify the effectiveness of this method. Thus the proposed method is practiced and could be used to identify the elastic properties of transversely isotropic materials. © 2023
语种：
英文
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Evolutional solid phase and solid-liquid interface uranium immobilization mechanisms by nanoscale zero-valent iron and enhanced uranium stability control strategy
作者：
Hua, Yilong;Li, Donghan;Zou, Jinglan;Wang, Wei;Wu, Xiaoyan;...
期刊：
Chemical Engineering Journal ,2023年453:139924 ISSN：1385-8947
通讯作者：
Yang, Jianping(jianpingyang@dhu.edu.cn)
作者机构：
[Hua, Yilong; Li, Mi; Zou, Jinglan; Yang, Jianping; Zhang, Xiaowen; Wu, Xiaoyan; Li, Donghan] Univ South China, Sch Resource Environm & Safety Engn, Hengyang 421001, Hunan, Peoples R China.;[Hua, Yilong; Yang, Jianping] Donghua Univ, Coll Mat Sci & Engn, State Key Lab Modificat Chem Fibers & Polymer Mat, Shanghai 201620, Peoples R China.;[Hua, Yilong; Li, Mi; Zou, Jinglan; Wang, Wei; Zhang, Xiaowen; Wu, Xiaoyan; Li, Donghan] Univ South China, United Lab Heavy Met Pollut Control & Resource Reu, Hengyang 421001, Hunan, Peoples R China.;[Zhao, Guodong; Liu, Qing] Univ South China, Hunan Key Lab Pollut Control & Resource Reuse, Hengyang 421001, Hunan, Peoples R China.;[Zhang, Wei-xian] Tongji Univ, Coll Environm Sci & Engn, State Key Lab Pollut Control, Shanghai 200092, Peoples R China.
通讯机构：
[Jianping Yang] S;School of Resource Environment and Safety Engineering, University of South China, Hengyang, Hunan 421001, China<&wdkj&>State Key Laboratory for Modification of Chemical Fibers and Polymer Materials, College of Materials Science and Engineering, Donghua University, Shanghai 201620, China
关键词：
Continuous flow stirred tank reactor;Eh control strategy;Nanoscale zero-valent iron;Uranium stability;Uranium wastewater
摘要：
Uranium is a carbon dioxide free nuclear energy, and uranium-contained wastewater poses serious chronic health effects toward human. Nanoscale zero-valent iron (nZVI) separates uranium from wastewater with ultrafast kinetic, high capacity and selectivity. However, the dynamic interfacial uranium binding mechanisms and its stability, controlled by the phase transformation of nZVI, is important but poorly understood. After 120 h reaction, the fresh nZVI was oxidized and transformed to ferrihydrite and then lepidocrocite and hematite. Analysis for the structures and valence states of U, Fe species indicated that the dominate U(VI) uptake mechanism changed from Fe0 induced reduction to adsorption as nZVI transformed to iron (oxyhydr)oxides. Density functional theory calculation revealed that uranyl formed corner-sharing configurations on the surface of iron nanoparticles, and some uranium ions prefer to incorporate into the structure of lepidocrocite than hematite during the crystallization processes of ferrihydrite. Meanwhile, 100 ∼ 10000 μg/L uranyl ions were quickly captured, the residual uranium could be maintained at ∼9.31 μg/L and the content of uranium in reacted iron nanoparticles reached ∼24.16 wt%. Interestingly, the oxidization reduction potential (Eh) was a potential parameter to control uranium immobilization in the CSTR system, and the Eh control strategy could be used to increase the fraction of U(IV)/U(V), sparingly soluble and highly stable, higher than 90 %. The findings augment our understanding of U-nZVI reactions and guide nZVI technology to remedy real uranium-contained wastewater. © 2022 Elsevier B.V.
语种：
英文
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Phosphorus-rich biochar modified with Alcaligenes faecalis to promote U(VI) removal from wastewater: Interfacial adsorption behavior and mechanism
作者：
Wang, Chenxu;Wang, Guohua;Xie, Shuibo;Dong, Zhitao;Zhang, Lantao;...
期刊：
Journal of Hazardous Materials ,2023年454:131484 ISSN：0304-3894
通讯作者：
Xie, SB
作者机构：
[Xie, Shuibo; Dong, Zhitao; Wang, Chenxu; Zhang, Lantao; Zhang, Zhiyue; Wang, Guohua; Deng, Yibo; Song, Jian] Univ South China, Sch Civil Engn, Hengyang 421001, Peoples R China.;[Xie, Shuibo] Univ South China, Key Discipline Lab Natl Def Biotechnol Uranium Min, Hengyang 421001, Peoples R China.
通讯机构：
[Xie, SB ] U;Univ South China, Sch Civil Engn, Hengyang 421001, Peoples R China.
关键词：
Biofilms;Composite materials;Metabolites;Phosphorus;Reusability;Water pollution;Adsorption behaviour;Adsorption mechanism;Alcaligenes faecalis;Biochar;Biocomposite;Extracellular;Interfacial adsorption;Phosphorus stability;Polymeric substance;Synergistic effect;Adsorption;calcium;calcium ion;charcoal;graphene oxide;Lewis acid;magnesium;metal ion;phosphate;phosphoric acid;phosphorus;sodium;uranium;charcoal;mineral;phosphorus;adsorption;bacterium;biochar;phosphate;phosphorus;uranium;wastewater;adsorption;Alcaligenes faecalis;aqueous solution;Article;biofilm;biomineralization;biosorption;chemisorption;complex formation;controlled study;corrosion;crystal structure;degradation;deprotonation;diffusion;dissolution;Fourier transform infrared spectroscopy;immobilization;isoelectric point;nonhuman;particulate matter;pore volume;porosity;reaction time;scanning electron microscopy;surface area;surface property;swine manure;viscosity;waste component removal;wastewater;adsorption;kinetics;wastewater;Adsorption;Alcaligenes faecalis;Charcoal;Kinetics;Minerals;Phosphates;Phosphorus;Uranium;Wastewater
摘要：
Phosphorus-rich biochar (PBC) has been extensively studied due to its significant adsorption effect on U(VI). However, the release of phosphorus from PBC into solution decreases its adsorption performance and reusability and causes phosphorus pollution of water. In this study, Alcaligenes faecalis (A. faecalis) was loaded on PBC to produce a novel biocomposite (A/PBC). After adsorption equilibrium, phosphorus released into solution from PBC was 2.32 mg/L, while it decreased to 0.34 mg/L from A/PBC (p < 0.05). The U(VI) removal ratio of A/PBC reached nearly 100%, which is 13.08% higher than that of PBC (p < 0.05), and it decreased only by 1.98% after 5 cycles. When preparing A/PBC, A. faecalis converted soluble phosphate into insoluble metaphosphate minerals and extracellular polymeric substances (EPS). And A. faecalis cells accumulated through these metabolites and formed biofilm attached to the PBC surface. The adsorption of metal cations on phosphate further contributed to phosphorus fixation in the biofilm. During U(VI) adsorption by A/PBC, A. faecalis synthesize EPS and metaphosphate minerals by using the internal components of PBC, thus increasing the abundance of acidic functional groups and promoting U(VI) adsorption. Hence, A/PBC can be a green and sustainable material for U(VI) removal from wastewater. © 2023 Elsevier B.V.
语种：
英文
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An activated carbon from walnut shell for dynamic capture of high concentration gaseous iodine
作者：
Yang, Xiaomin;Xie, Dong;Wang, Weihao;Li, Suzhe;Tang, Zengming;...
期刊：
Chemical Engineering Journal ,2023年454:140365 ISSN：1385-8947
通讯作者：
Xie, Dong(xiedong@usc.edu.cn)
作者机构：
[Li, Suzhe; Tang, Zengming; Yang, Xiaomin] Univ South China, Sch Resource Environm & Safety Engn, Hengyang 421001, Peoples R China.;[Xie, Dong; Li, Suzhe; Tang, Zengming; Yang, Xiaomin] Natl & Local Joint Engn Res Ctr Airborne Pollutant, Hengyang 421001, Peoples R China.;[Xie, Dong; Dai, Shiliang] Univ South China, Sch Civil Engn, Hengyang 421001, Peoples R China.;[Dai, Shiliang; Wang, Weihao] Hunan Sunny Technol Engn Co Ltd, Hengyang 421001, Peoples R China.
通讯机构：
[Dong Xie] N;National and Local Joint Engineering Research Center of Airborne Pollutants Treatment and Radioactive Protection in Building Environment, Hengyang 421001, China<&wdkj&>School of Civil Engineering, University of South China, Hengyang 421001, China
关键词：
Activated carbon;Dynamic adsorption;Gaseous iodine;Grey relational analysis;Walnut shell
摘要：
In order to capture the high concentration gaseous iodine from off-gas streams under nuclear accident conditions, an advanced activated carbon was prepared by using walnut shell as a raw material and zinc chloride as an activator agent (named WS-ZnCl2). The pore structure and functional groups characteristics of the adsorbent were researched via three techniques including N2 adsorption–desorption isotherms, transmission electron microscope (TEM), and Fourier transform infrared spectroscopy (FTIR). The Brunauer-Emmett-Teller (BET) surface area, the total pore volume and the average pore size of the adsorbent were observed to be 1360 m2/g, 0.68 cm3/g and 2.00 nm, respectively. In addition, the adsorption capacities of the adsorbent to capture gaseous iodine were investigated with static and dynamic experimental adsorption methods. The results of the static experimental adsorption indicated that the gaseous iodine equilibrium adsorption capacity of the walnut shell before and after ZnCl2 activation increased from 606 mg/g to 2374 mg/g at condition of 80 °C and ambient pressure. The dynamic adsorption performance of the adsorbent for capture of gaseous iodine was studied by varying operating parameters, such as temperature, adsorption column height, and the flow rate. More significantly, the maximum dynamic adsorption capacity of the adsorbent for capture gaseous iodine reached a record of 1634 mg/g at 60 °C, 2.2 cm and 250 mL/min. Finally, the importance ranking of the influencing factors on the dynamic adsorption was analyzed by Grey relational analysis (GRA) method. The results showed that adsorption capacity was obviously affected by flow rate, whereas adsorption time was highly influenced by adsorption column height. The adsorbent researched in this paper has potential to capture high concentration gaseous iodine. © 2022 Elsevier B.V.
语种：
英文
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Preparation of manganese dioxide/hollow mesoporous silica spheres (MnO2/HMSS) composites for removal of Sr(Ⅱ) from aqueous solution
作者：
Zheng, Jiahao;Yang, Yuyin;Dai, Zhaolong;Wang, Jingsong;Xia, Yulin;...
期刊：
Colloids and Surfaces A: Physicochemical and Engineering Aspects ,2023年666:131298 ISSN：0927-7757
通讯作者：
Wang, JS
作者机构：
[Wang, JS; Wang, Jingsong; Dai, Zhaolong; Zheng, Jiahao] Univ South China, Sch Civil Engn, Hengyang 421001, Hunan, Peoples R China.;[Li, Chenxu; Yang, Yuyin; Xia, Yulin] Minist Ecol & Environm MEE, South China Inst Environm Sci SCIES, Guangzhou 510655, Peoples R China.
通讯机构：
[Wang, JS ] U;Univ South China, Sch Civil Engn, Hengyang 421001, Hunan, Peoples R China.
关键词：
Adsorption;Hollow mesoporous silica;Radioactive wastewater;Strontium
摘要：
Strontium ion in radioactive wastewater causes serious harm to the biological and ecological environment, so the removal of strontium ion is of great significance. We have prepared an inorganic adsorption material (MnO2/HMSS) by impregnation method. The adsorbent can effectively remove Sr2+ in radioactive wastewater. The synthetic materials were characterised by X-ray diffraction (XRD), Scanning electron microscope (SEM), X-ray spectroscopy (EDS), Fourier-transform infrared spectroscopy (FTIR), X-ray photoelectron spectroscopy (XPS) and N2 adsorption-desorption isotherms. The effects of the mass ratio of manganese dioxide and hollow mesoporous silica spheres, pH, initial concentration of Sr2+, adsorption time, competitive ion and other parameters on the adsorption properties were systematically investigated. The results showed that the 4:1Mn02/HMSS composite had the highest adsorption capacity. The adsorption of Sr2+ on MnO2/HMSS is highly dependent on pH and initial solubility. Furthermore, the adsorption equilibrium is reached at 120 min, with a maximum adsorption capacity of 138.70 mg/g. In addition, the composite still maintains a good adsorption capacity under a variety of competitive ions. The Langmuir and pseudo-second-order models can better fit the adsorption isotherm and kinetic data than the Freundlich and pseudo-first-order models, respectively. The new composite obtained in this work has the advantages of rapid adsorption, large adsorption capacity, strong selectivity and capable of large-scale preparation, which makes it expected to play an important role in the removal of strontium ions. © 2023 Elsevier B.V.
语种：
英文
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Application of the hybrid neural network model for energy consumption prediction of office buildings
作者：
Wang, Lize;Xie, Dong;Zhou, Lifeng;Zhang, Zixuan
期刊：
Journal of Building Engineering ,2023年72:106503 ISSN：2352-7102
通讯作者：
Xie, D
作者机构：
[Zhang, Zixuan; Xie, D; Xie, Dong; Zhou, Lifeng; Wang, Lize] Univ South China, Sch Civil Engn, Hengyang 421001, Peoples R China.;[Zhang, Zixuan; Xie, Dong; Zhou, Lifeng; Wang, Lize] Natl & Local Joint Engn Res Ctr Airborne Pollutant, Hengyang 421001, Peoples R China.
通讯机构：
[Xie, D ] U;Univ South China, Sch Civil Engn, Hengyang 421001, Peoples R China.
关键词：
Convolution;Energy utilization;Forecasting;Recurrent neural networks;Attention mechanisms;Bi-directional;Bi-directional gated recurrent unit;Building energy;Building energy prediction;Convolution neural network;Energy prediction;Hybrid neural networks;Prediction accuracy;Residual connection;Office buildings
摘要：
Accurate building energy consumption prediction is crucial to the rational planning of building energy systems. The energy consumption of buildings is influenced by various elements and is characterized by non-linearity and non-stationarity. To fully tap the time series characteristics of building energy consumption and heighten the model's prediction accuracy, this paper proposes a hybrid neural network prediction model combining attention mechanism, Bidirectional Gate Recurrent Unit (BiGRU), Convolutional Neural Networks (CNN), and the residual connection. The model uses BiGRU to train the extracted feature vectors by CNN on a two-way cycle. The attention mechanism highlights the key information extracted, and the residual connection is used to learn the features fully. Taking the energy consumption data of an office building in Guangzhou, China, as the object of study, the results indicate that the proposed model shows a stronger prediction accuracy than the commonly used model with an R2 of 90.74% and a CV-RMSE of 19.24%. Compared with the other five common models, the RMSE, MAPE, and MAE of the proposed model achieve lower error rates. Besides, the length 24 of the sliding window exceeds other lengths in the established model. The prediction accuracy of the established model in working hours outperforms the non-working hours of the office building. Building energy consumption prediction in the same season is better than that in the whole year. © 2023 Elsevier Ltd
语种：
英文
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Visible-light-driven removal of AO7 by peroxymonosulfate-assisted Z-scheme AgBr/LaFeO3 heterojunction vis accelerated electronic transfer
作者：
Huang, Shiyuan;Yuan, Hanqin;Dong, Wen;Wu, Xingliang;Wang, Guohua
期刊：
Materials Science in Semiconductor Processing ,2023年160:107414 ISSN：1369-8001
通讯作者：
Huang, Shiyuan(hsyuan_861@163.com)
作者机构：
[Dong, Wen; Huang, Shiyuan; Yuan, Hanqin; Wu, Xingliang; Wang, Guohua] Univ South China, Sch Civil Engn, Hengyang 421001, Hunan, Peoples R China.;[Wang, Guohua] Univ South China, Hunan Prov Key Lab Pollut Control & Resources Tech, Hengyang 421001, Hunan, Peoples R China.
通讯机构：
[Shiyuan Huang] S;School of Civil Engineering, University of South China, Hengyang, 421001, Hunan, China
关键词：
Bromine compounds;Charge transfer;Citrus fruits;Heterojunctions;Iron compounds;Photocatalysis;Precipitation (chemical);Reusability;Silver halides;Solar energy;Acid orange 7;Agbr/LaFeO3;Charge-separation;Electronic transfers;LaFeO 3;Peroxymonosulfate;Simple++;Synthesised;Visible-light-driven;Z-scheme;Lanthanum compounds
摘要：
In this work, AgBr/LaFeO3 (ALFO) Z-scheme heterojunction photocatalyst was successfully synthesized by simple in-situ precipitation method, and photocatalysis was coupled with peroxymonosulfate (PMS) to remove acid orange 7 (AO7) by enhanced electron transfer. The Z-scheme heterojunction between AgBr and LaFeO3 provides the driving force for charge transfer and improves the charge separation rate. At the same time, PMS can act as an electron acceptor to promote photogenerated charge separation and maximize the generation of reactive oxygen species. The obtained results showed that the prepared ALFO photocatalyst has excellent reusability and excellent AO7 removal efficiency. This work successfully demonstrated the synergistic effect of ALFO photocatalyst, promoted light utilization and PMS activation, and provided a potential application prospect for effectively reducing environmental pollution by using solar energy. © 2023 Elsevier Ltd
语种：
英文
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锰氮共掺杂稻壳生物炭活化过二硫酸盐降解酸性橙
作者：
黄仕元;林森焕;董雯;王国华;吴兴良;...
期刊：
复合材料学报 ,2023年40(2):1071-1084 ISSN：1000-3851
通讯作者：
Huang, Shiyuan(550903597@qq.com)
作者机构：
[黄仕元; 林森焕; 董雯; 王国华; 吴兴良; 袁瀚钦] School of Civil Engineering, University of South China, Hengyang;421001, China;[黄仕元; 林森焕; 董雯; 王国华; 吴兴良; 袁瀚钦] 421001, China
通讯机构：
[Huang, S.] S;School of Civil Engineering, China
关键词：
生物炭;杂原子;共掺杂;过二硫酸盐;降解染料
摘要：
为了更好地处理水环境中的偶氮染料(酸性橙,AO7)污染问题,以稻壳、尿素和锰盐为原料,通过热解法制备Mn、N共掺杂生物炭复合材料(Mn-N-BC),活化过二硫酸盐(PDS)降解酸性橙(AO7)染料废水。考察了AO7初始浓...展开更多 为了更好地处理水环境中的偶氮染料(酸性橙,AO7)污染问题,以稻壳、尿素和锰盐为原料,通过热解法制备Mn、N共掺杂生物炭复合材料(Mn-N-BC),活化过二硫酸盐(PDS)降解酸性橙(AO7)染料废水。考察了AO7初始浓度、PDS浓度、催化剂投加量、初始pH值等因素对AO7去除率的影响。结果显示:Mn-N-BC/PDS体系对AO7染料具有较高的去除率,在30 min内可达为98.6%,其表观速率常数kobs为0.125 min-1;并且对水环境中的无机阴离子表现出较高的抗性。在3次循环利用后,AO7的去除率仍在75%左右,表明Mn-N-BC对有机污染物的去除具有较高的可重复利用性和稳定性。自由基淬灭研究、XPS分析表明:Mn-N-BC/PDS体系中AO7的降解机制包括自由基途径(·OH、SO4-·)和非自由基途径(O2-·、1O2和电子转移),其中非自由基途径为主要作用。收起
语种：
中文
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A NEW ROCKBURST CRITERION OF STRESS-STRENGTH RATIO CONSIDERING STRESS DISTRIBUTION OF SURROUNDING ROCK
作者：
Liu, Xiqi;Wang, Gang;Song, Leibo;Han, Guansheng;Chen, Wenzhao;...
期刊：
Bulletin of Engineering Geology and the Environment ,2023年82(1):1-13 ISSN：1435-9529
通讯作者：
Wang, Gang(2021000077@usx.edu.cn)
作者机构：
[Liu, Xiqi; Wang, Gang] Wuhan Univ, Sch Civil Engn, Key Lab Geotech & Struct Engn Safety Hubei Prov, Wuhan 430070, Peoples R China.;[Han, Guansheng; Wang, Gang; Chen, Hao; Song, Leibo] Shaoxing Univ, Sch Civil Engn, Shaoxing 312000, Peoples R China.;[Chen, Wenzhao] Univ South China, Sch Civil Engn, Hengyang 421001, Peoples R China.
通讯机构：
[Gang Wang] K;Key Laboratory of Geotechnical and Structural Engineering Safety of Hubei Province, School of Civil Engineering, Wuhan University, Wuhan, China<&wdkj&>School of Civil Engineering, Shaoxing University, Shaoxing, China
关键词：
Rockburst intensities;Rockburst prediction;Strain rockburst;Stress gradient;Stress–strength ratio
摘要：
Rockburst is a common geological disaster in the process of deep rock excavation, and stress gradient is an important factor affecting rockburst. In this paper, the concept of “stress concentration” was proposed. The relevant data of a large number of engineering rockburst cases were statistically analyzed, and a new rockburst criterion of stress–strength ratio considering stress gradient of surrounding rock was established. The research results revealed that the rockburst criterion considering the stress gradient distribution of surrounding rock could effectively overcome the problem of non-uniform division of rockburst criteria in the traditional strength-to-stress ratio. It can fully reflect the influence of tunnel size effect on rockburst. There was a significant correlation between rockburst strength and stress gradient, and different rockburst strengths showed obvious zoning concentration phenomenon on the two-dimensional plane. The established rockburst criterion considering the stress intensity ratio of surrounding rock had strong applicability, and the prediction accuracy could reach more than 90%. The proposed rockburst criterion in this paper has certain theoretical and engineering guiding value for the early warning of underground engineering disasters. © 2022, Springer-Verlag GmbH Germany, part of Springer Nature.
语种：
英文
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Crack initiation mechanism and meso-crack evolution of pre-fabricated cracked sandstone specimens under uniaxial loading
作者：
Sun, Bing;Yang, Haowei;Zeng, Sheng;Yin, Yu;Fan, Junwei
期刊：
Geomechanics and Engineering ,2023年33(6):597-609 ISSN：2005-307X
通讯作者：
Sun, B;Zeng, S
作者机构：
[Sun, Bing; Fan, Junwei; Yang, Haowei] Univ South China, Sch Civil Engn, Hengyang 421001, Hunan, Peoples R China.;[Zeng, Sheng; Zeng, S; Yin, Yu] Univ South China, Sch Resources Environm & Safety Engn, Hengyang 421001, Hunan, Peoples R China.;[Yin, Yu] Sinosteel Maanshan Gen Inst Min Res Co Ltd, Maanshan 243000, Anhui, Peoples R China.
通讯机构：
[Sun, B ; Zeng, S ] U;Univ South China, Sch Civil Engn, Hengyang 421001, Hunan, Peoples R China.;Univ South China, Sch Resources Environm & Safety Engn, Hengyang 421001, Hunan, Peoples R China.
关键词：
acoustic emission;fracture mechanics;meso-crack evolution;pre-fabricated cracked sandstone;uniaxial compression
摘要：
The instability and failure of engineered rock masses are influenced by crack initiation and propagation. Uniaxial compression and acoustic emission (AE) experiments were conducted on cracked sandstone. The effect of the crack’s dip on the crack initiation was investigated using fracture mechanics. The crack propagation was investigated based on stress-strain curves, AE multi-parameter characteristics, and failure modes. The results show that the crack initiation occurs at the tip of the prefabricated crack, and the crack initiation angle increases from 0° to 70° as the dip angle increases from 0° to 90°. The fracture strength kcr is derived varies in a U-shaped pattern as β increased, and the superior crack angle βm is between 36.2 and 36.6 and is influenced by the properties of the rock and the crack surface. Low-strength, large-scale tensile cracks form during the crack initiation in the cracked sandstone, corresponding to the start of the AE energy, the first decrease in the b-value, and a low r-value. When macroscopic surface cracks form in the cracked sandstone, high-strength, large-scale shear cracks form, resulting in a rapid increase in the AE energy, a second decrease in the b-value and an abrupt increase in the r-value. This research has significant theoretical implications for rock failure mechanisms and establishment of damage indicators in underground engineering. © 2023 Techno-Press, Ltd.
语种：
英文
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主动平移模式下墙后非饱和砂土破坏模式及侧向土压力分布试验研究
作者：
邓波;杨明辉;赵明华
期刊：
岩土工程学报 ,2023年45(1):94-102 ISSN：1000-4548
通讯作者：
Yang, Minghui(yamih@hnu.edu.cn)
作者机构：
[邓波] School of Civil Engineering, University of South China, Hengyang;421001, China;[杨明辉] School of Architecture and Civil Engineering, Xiamen University, Xiamen;361005, China;[赵明华] College of Civil Engineering, Hunan University, Changsha
关键词：
非饱和土;主动土压力;界面粗糙度;刚性挡墙;模型试验
摘要：
在主动平移模式下，开展一系列不同墙面粗糙度和砂土含水量情况下刚性挡墙主动土压力室内模型试验，通过渗压计和土压力盒分别监测了基质吸力和土压力的变化，并基于DIC图像关联技术获取破裂面位置，进而分析了基质吸力和界面粗糙度对主动土压力和土体破裂面形状的影响。试验结果表明：随着含水量增加，砂土破裂面逐渐向外移，原因在于当砂土基质吸力大于其进气值时，吸应力随基质吸力的增大而减少，进而使土体抗剪强度降低；达到主动极限状态后，破裂面过墙踵，但比库仑破裂面要浅，二者差异随基质吸力减少而增大；墙土界面摩擦对滑动破裂面形状的影响很小。此外，主动土压力在墙体中上部区域，随着深度增加而近似呈线性增大，但在墙踵附近区域，松砂传递的摩阻力使土压力出现略有降低；实测主动土压力值始终小于库仑主动土压力值，其差值随着含水量的增大而增大；相比摩擦角的影响，吸应力对土压力作用更为明显。
语种：
中文
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Oxygen-containing functional groups enhance uranium adsorption by aged polystyrene microplastics: Experimental and theoretical perspectives
作者：
Tang, Zhenping;Zhu, Feiyu;Jiang, Tianyun;Wei, Fuxing;Gao, Yuanyuan;...
期刊：
Chemical Engineering Journal ,2023年465:142730 ISSN：1385-8947
通讯作者：
Zhou, Shuai(zs402606665@126.com)
作者机构：
[Zhou, Shuai; Duan, Yi; Xiang, Chao; Tang, Zhenping] Univ South China, Hunan Prov Key Lab Pollut Control & Resources Reus, Hengyang 421001, Peoples R China.;[Gao, Yuanyuan; Hua, Yilong; Zhou, Shuai; Wei, Fuxing; Zhu, Feiyu; Jiang, Tianyun; Tang, Zhenping] Univ South China, Hunan Prov Key Lab Rare Met Minerals Exploitat & G, Hengyang 421001, Peoples R China.;[Wang, Yayi] Tongji Univ, Coll Environm Sci & Engn, State Key Lab Pollut Control & Resources Reuse, Siping Rd, Shanghai 200092, Peoples R China.
通讯机构：
[Shuai Zhou] H;[Yayi Wang] S;State Key Laboratory of Pollution Control and Resources Reuse, College of Environmental Science and Engineering, Tongji University, Siping Road, Shanghai 200092, China<&wdkj&>Hunan Province Key Laboratory of Pollution Control and Resources Reuse Technology, University of South China, Hengyang 421001, China<&wdkj&>Hunan Province Key Laboratory of Rare Metal Minerals Exploitation and Geological Disposal of Wastes, University of South China, Hengyang 421001, China
关键词：
Polystyrene microplastics (PS MPs);Uranium (U);Aging;Oxygen -containing functional groups;Adsorption;Density functional theory
摘要：
Although oxygen-containing functional groups generated during unavoidable aging play a key role in improving the adsorption performance of heavy metals by microplastics (MPs), little is known about the contribution of such groups to the interactions between highly toxic radioactive heavy metals and aged MPs. Here, we used a combination of batch experiments and density functional theory calculations to examine the effects and mechanisms of aging and the produced oxygen-containing functional groups, i.e., C═O, –OH, phenolic hydroxyl (–OHm), and –COOH, on the adsorption behavior of representative radionuclide uranium (U) on polystyrene (PS) MPs. The kinetic experimental results showed that the amount of U adsorption by the aged PS MPs was significantly higher than that of virgin PS MPs (P < 0.05). Binding-energy and thermodynamic data indicated that the affinity of PS MPs to a typical U species, i.e., uranyl, followed the order of PS═O–OHm > PS═O > PS–COOH > PS–OH > PS–OHm > virgin PS. Characterization and surface potential analyses demonstrated that the electronegative oxygen atoms in oxygen-containing functional groups in the aged PS MPs increased along with the aging time, and could serve as potential sites for electrostatic interactions with uranyl. Intramolecular interaction calculations confirmed that hydrogen bonding by oxygen-containing functional groups could strengthen the interactions between uranyl and aged PS MPs via electrostatic and polarization effects. Our findings provide an in-depth understanding of the role of aging in U adsorption by MPs, which is critical for assessing the fate of coexisting radionuclides and MPs in the environment, and their associated risks.
语种：
英文
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Effects of high temperatures on the splitting tensile strength and gamma ray shielding performance of radiation shielding concrete
作者：
Luo, Lincheng;Chen, Zhenfu;Tao, Qiuwang;Xie, Liping;Jin, Dan;...
期刊：
Construction and Building Materials ,2022年343:127953 ISSN：0950-0618
通讯作者：
Tao, Qiuwang(taoqiuwang@usc.edu.cn)
作者机构：
[Deng, Du; Li, Zhujing; Chen, Zhenfu; Tao, Qiuwang; Jin, Dan; Luo, Lincheng] Univ South China, Sch Civil Engn, Hengyang 421001, Hunan, Peoples R China.;[Deng, Du; Chen, Zhenfu; Tao, Qiuwang; Luo, Lincheng] Univ South China, China Nucl Ind Key Lab High Performance Concrete, Hengyang 421001, Hunan, Peoples R China.;[Deng, Du; Li, Zhujing; Chen, Zhenfu; Tao, Qiuwang; Jin, Dan; Luo, Lincheng] Univ South China, Hunan Prov Key Lab High Performance Special Concre, Hengyang 421001, Hunan, Peoples R China.;[Xie, Liping] China Nucl Ind 22ND Construct Co Ltd, Yichang 443101, Hubei, Peoples R China.
通讯机构：
[Qiuwang Tao] S;School of Civil Engineering, University of South China, Hengyang 421001, Hunan Province, China<&wdkj&>China Nuclear Industry Key Laboratory of High-Performance Concrete, University of South China, Hengyang 421001, Hunan Province, China<&wdkj&>Hunan Provincial Key Laboratory of High-Performance Special Concrete, University of South China, Hengyang 421001, Hunan Province, China
关键词：
Barite;Gamma ray shielding;High temperature;Magnetite;Radiation shielding concrete;Splitting tensile strength
摘要：
The residual properties of radiation shielding concrete subjected to high temperatures require reassessment, considering that it may be exposed to high temperatures during service life. In this study, the effects of high temperatures on apparent characteristic, mass loss, splitting tensile strength, ultrasonic pulse velocity and gamma ray shielding performance of the more widely used barite concrete and magnetite concrete were investigated. The results showed that the relative velocity and damage index had a good correlation with the relative splitting tensile strength of radiation shielding concrete exposed to high temperatures, which could accurately reflect the failure of radiation shielding concrete subjected to high temperatures. Meanwhile, barite concrete appeared severe spalling phenomenon at 450 ℃, and magnetite concrete had better thermal stability, which had favorable physical, mechanical and shielding properties, thus it was more suitable for concrete under high temperature. © 2022 Elsevier Ltd
语种：
英文
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新型除氟吸附材料的研究进展
作者：
田追;张震;卢嫚;杨斌;杨金辉;...
期刊：
化工进展 ,2022年41(6):3051-3062 ISSN：1000-6613
作者机构：
[田追; 张震; 卢嫚; 杨斌; 杨金辉; 周书葵; 魏柏; 李聪] School of Civil Engineering, University of South China, Hunan, Hengyang;421001, China;[田追; 张震; 卢嫚; 杨斌; 杨金辉; 周书葵; 魏柏; 李聪] 421001, China
关键词：
吸附;吸附剂;改性;机理分析;氟离子
摘要：
半导体，稀土开采等行业所排放的氟废水所引发氟中毒现象备受关注。吸附法是去除废水中氟离子的有效方法之一，但传统吸附剂存在吸附容量低、选择性差等缺点问题，亟需研发具有高吸附容量能再生，且无二次污染的吸附材料。本文归纳了一些新型吸附材料:高分子材料吸附剂、生物炭、层状双氢氧化物、工业废弃物、纳米材料及其改性材料在含氟废水中的研究应用；总结了这些改性材料的制备过程，介绍了这些材料吸附除氟的能力，分析了新型吸附材料吸附除氟的机理以及共存离子干扰、pH适用范围等影响因素，并指出了材料制备存在的问题，为在今后除氟领域开发有效吸附剂，提出了未来如何制备对氟离子具有高选择性能的改性吸附材料的发展方向和材料循环利用所需解决的重要问题。
语种：
中文
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稻壳基材料应用于水污染治理领域的研究进展
作者：
胡世琴;杨金辉;杨斌;王劲松;周书葵;...
期刊：
材料导报 ,2022年36(4):45-55 ISSN：1005-023X
作者机构：
[胡世琴; 杨金辉; 杨斌; 王劲松; 周书葵; 雷增江; 骆毅] School of Civil Engineering, University of South China, Hengyang;421001, China;[胡世琴; 杨金辉; 杨斌; 王劲松; 周书葵; 雷增江; 骆毅] 421001, China
关键词：
稻壳;吸附;光催化;重金属离子;有机污染物
摘要：
随着工业的快速发展,电镀设备、采矿、纺织等行业排放的废水含有大量的重金属离子和有机污染物,这些污染物严重危害人类的身体健康。因此,如何快速有效地处理水体中的重金属离子和有机污染物是环境修复领域中亟待解决的问题。稻壳因具有来源广泛、可再生、环境友好等特点而被广泛应用于吸附材料和光催化材料领域。大量研究表明,稻壳能够去除污染水体中重金属离子和有机物的种类很多,但是对大多数污染物的去除能力不强,难以在实际应用中得到进一步推广。以稻壳为基体材料制备有高效去除能力的功能性材料,是近几年环境修复领域的研究热点。目前,研究者尝试以炭化、化学修饰等方式对稻壳改性,从而增大比表面积、孔隙率或者增加含氧官能团的数量,吸附性能也能随之改善,但是以上改性后的稻壳材料存在吸附能力弱和容易产生二次污染等问题。研究发现,负载Fe_3O_4制备的磁性稻壳生物炭复合材料,不仅吸附性能强,且具有易分离、稳定性强、不会对环境造成二次污染等优点,这为稻壳基材料在实际应用的推广奠定了基础。另外,有研究报道,将稻壳中的SiO_2作为半导体光催化剂(如TiO_2 、Ni_2 O_3 )的载体可提高其光催化性能、回收利用率,使其在光学领域具有良好的使用性能。本文综述了稻壳材料本身的特性和改性稻壳制备稻壳基吸附剂的方法,讨论了稻壳基及其复合材料在水污染治理领域中作为吸附剂和光催化剂的应用。从不同类型的污染物角度出发,论述了稻壳基材料针对重金属离子、有机污染物处理过程中稻壳掺杂材料功能及体系作用机理的影响,还分析了影响污染物吸附的重要因素,最后对目前稻壳基材料在水治理领域应用进行了总结和对今后的研究方向做了展望。
语种：
中文
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Hygro-thermo-elastic behavior for stiffened metal doubly-curved shallow shells with porous microcapsule coating under low-velocity impact considering in-plane initial load
作者：
He, Qi;Hong-Liang Dai;Zhang, Zhang;Tang, Hong
期刊：
Composite Structures ,2022年284:115213 ISSN：0263-8223
通讯作者：
Dai, HL
作者机构：
[Hong-Liang Dai; Dai, HL; He, Qi; Tang, Hong; Zhang, Zhang] Hunan Univ, State Key Lab Adv Design & Mfg Vehicle Body, Changsha 410082, Hunan, Peoples R China.;[He, Qi] Univ South China, Sch Civil Engn, Hengyang 421001, Peoples R China.
通讯机构：
[Dai, HL ] H;Hunan Univ, State Key Lab Adv Design & Mfg Vehicle Body, Changsha 410082, Hunan, Peoples R China.
关键词：
Doubly-curved shallow shell;In-plane initial load;Low-velocity impact;Microcapsule coating;Porosity
摘要：
Low-velocity impact response of stiffened metal doubly curved shallow shells with porous microcapsule coating in hygrothermal environment is analyzed considering the in-plane initial load. A modified nonlinear Hertzian contact law which ignores the influence of friction is considered for the low velocity impact problem. Based on the classical shell theory considering the von Kármán geometric nonlinearity, the governing equations of motion for this structure are derived from the Hamilton's variation principle while the finite difference method (FDM) and Newmark-β algorithm are used to solve the equations. The effects of temperature and moisture, initial velocity of impactor, properties of metal substrate, initial load, geometry parameters of microcapsules, geometry parameters of the stiffened shell and porosity on the transient impact response of the stiffened shell are examined and analyzed. Initial impact velocity, properties of metal substrate and porosity have a significant effect on contact force and central deflection. Normal stress is greatly affected by temperature, properties of metal substrate, geometry parameters of the stiffened shell and porosity. Moreover, the impact resistance of stiffened shells is enhanced by the in-plane initial tensile load while the effect of in-plane initial compressive load is opposite. © 2022
语种：
英文
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生物炭负载绿色纳米铁颗粒去除水中U(VI)
作者：
刘清;许艺文;招国栋;滑熠龙;李伟凡
期刊：
复合材料学报 ,2022年39(12):5934-5945 ISSN：1000-3851
通讯作者：
Liu, Qing(liuqing197901@163.com)
作者机构：
[刘清; 许艺文; 李伟凡] College of Civil Engineering, University of South China, Hengyang;421001, China;[招国栋; 滑熠龙] College of Resource Environment and Safety Engineering, University of South China, Hengyang;[刘清; 许艺文; 招国栋; 滑熠龙; 李伟凡] 421001, China
通讯机构：
[Liu, Q.] C;College of Civil Engineering, China
关键词：
向日葵叶;生物炭;纳米铁颗粒;铀;吸附;还原
摘要：
铀矿开采与水冶过程产生大量铀废水,对周边生态环境造成污染,因此高效绿色治理是保障核工业可持续发展及生态安全的重要基础。本文以向日葵叶为原料绿色合成生物炭负载纳米铁颗粒(GN-FeNPs/BC),并用于去除水中的U(VI)。利用向日葵叶制备植物提取液,然后将残渣热解制备成生物炭,最后将七水硫酸亚铁溶液、生物炭和植物提取液混合,成功制备出绿色纳米铁复合材料。探究了生物炭碳化温度、铁碳比、 pH值、温度、时间和U(VI)浓度对除铀的影响。在298 K、pH=5时,最大吸附量为96.43 mg·g~(-1),并进行动力学和热力学研究。结果表明,准二级动力学模型和Langmuir等温吸附模型拟合良好。热力学常数表明GNFeNPs/BC对U(VI)的吸附是一个自发吸热的过程。XPS分析表明去除机制包括吸附作用和还原作用。
语种：
中文
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MXene/SA凝胶微球的制备及对U(VI)的吸附性能
作者：
李仕友;胡俊毅;贺俊钦;汪杨;乔记帅;...
期刊：
复合材料学报 ,2022年39(10):4868-4878 ISSN：1000-3851
通讯作者：
Wang, Guohua(wghcsu@163.com)
作者机构：
[李仕友; 胡俊毅; 贺俊钦; 汪杨; 乔记帅; 王国华] School of Civil Engineering, University of South China, Hengyang;421001, China;Hunan Provincial Key Laboratory of Pollution Control and Resources Technology, University of South China, Hengyang;[李仕友; 王国华] 421001, China <&wdkj&> Hunan Provincial Key Laboratory of Pollution Control and Resources Technology, University of South China, Hengyang;[李仕友; 胡俊毅; 贺俊钦; 汪杨; 乔记帅; 王国华] 421001, China
通讯机构：
[Wang, G.] S;[Wang, G.] H;School of Civil Engineering, China;Hunan Provincial Key Laboratory of Pollution Control and Resources Technology, China
关键词：
海藻酸钠;凝胶微球;铀;吸附性能
摘要：
为了提高纳米材料MXene的吸附能力和可回收性,采用离子交联法将海藻酸钠(SA)和MXene混合,使Ti_3C_2Tx MXene纳米材料固定在SA凝胶基质上,经冷冻干燥后制备了MXene/SA凝胶微球。通过SEMEDS 、FTIR和XPS对凝胶微球结构进行了表征,并考察了不同因素影响下MXene/SA凝胶微球对水溶液中铀(VI)的吸附特性,并探究了其循环再生能力。结果表明,MXene/SA凝胶微球对铀吸附过程遵循拟二级动力学和Langmuir等温吸附模型,说明该吸附主要为单分子层化学吸附,且热力学参数表明其吸附过程是一个自发吸热的过程。在pH为4,温度为298 K时,MXene/SA凝胶微球对铀的最大吸附量为126.82 mg·g~(-1),其主要吸附机制是离子交换与络合作用。更重要的是该凝胶微球经5次循环后,去除率仍然保持在90%以上,说明吸附剂具有回收再生利用性能,且不会造成水环境的二次污染。因此,MXene/SA凝胶微球吸附剂在修复放射性核素铀废水污染方面表现出巨大潜力。
语种：
中文
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氨化烟末生物碳吸附剂的制备及其对Cr(VI)的吸附行为
作者：
杨金辉;胡世琴;杨斌;谢水波;雷增江;...
期刊：
复合材料学报 ,2022年39(1):222-231 ISSN：1000-3851
通讯作者：
Yang, Bin(932936624@qq.com)
作者机构：
[杨金辉; 胡世琴; 杨斌; 谢水波; 雷增江; 李聪] University of South China, School of Civil Engineering, 421001, China
通讯机构：
[Yang, B.] U;University of South China, School of Civil Engineering, China
关键词：
吸附;氨化;烟末;生物碳;机理
摘要：
以卷烟废弃烟末为原材料,对其进行碳化处理后再引入氨基功能团制备氨化烟末生物碳吸附剂(NH_2/TPB),研究pH、投加量、温度、吸附时间对NH_2/TPB吸附Cr(Ⅵ)的影响。通过扫描电镜(SEM)、傅里叶红外光谱(FTIR)、X射线光电子能谱(XPS)等技术进行机制分析。结果表明:初始浓度为210 mg/L、pH= 4、投加量为0.8 g/L、温度为45℃、吸附时间为120 min时,NH_2/TPB对Cr(Ⅵ)的最大吸附量为103.627 mg/g。吸附过程符合准二级动力学模型和Langmuir吸附等温模型。Cr(Ⅵ)吸附去除机制主要包括静电相互作用、还原反应以及与-NH_2、-OH、-COOH的配位络合,与Si-O-Si的"π-π"相互作用。通过5次吸附-解吸试验发现,Cr(Ⅵ)去除率在82.88%以上。研究表明氨化烟末生物碳具备处理与修复酸性含Cr(Ⅵ)废水污染的潜力。
语种：
中文
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钴强化铁磁体活化过一硫酸盐的实验研究
作者：
黄仕元;邓简;袁瀚钦;王国华;吴兴良
期刊：
化工学报 ,2022年73(7):3045-3056 ISSN：0438-1157
通讯作者：
Huang, Shiyuan(550903597@qq.com)
作者机构：
[黄仕元; 邓简; 袁瀚钦; 王国华; 吴兴良] School of Civil Engineering, University of South China, Hunan, Hengyang;421001, China;Hunan Provincial Key Laboratory of Pollution Control and Resources Technology, University of South China, Hunan, Hengyang;[黄仕元; 邓简; 袁瀚钦; 王国华; 吴兴良] 421001, China;[王国华] 421001, China<&wdkj&>Hunan Provincial Key Laboratory of Pollution Control and Resources Technology, University of South China, Hunan, Hengyang
关键词：
铁磁体;尖晶石;复合材料;活化;过硫酸盐;降解
摘要：
采用溶剂热法后高温煅烧的方式制备了铁钴双金属复合催化剂,用以活化过一硫酸盐(PMS)降解偶氮染料金橙Ⅱ(OGⅡ)。通过X射线衍射仪、扫描电子显微镜、振动样品磁强计和X射线光电子能谱仪等仪器对复合材料进行了表征。考察了钴复合量、不同去除体系、催化剂投加量、PMS投加量、污染物浓度、pH和共存阴离子等因素对OGⅡ降解效果的影响,并探究了铁钴复合催化剂重复利用的效果。实验结果表明,铁钴复合催化剂可以有效活化PMS降解OGⅡ,在n(Co_3O_4)∶n(Fe_2O_3)=0.1、催化剂投加量为1.0 g/L、PMS投加量为0.4 mmol/L、OGⅡ浓度为30 mg/L、溶液pH为6.2的条件下,反应60 min后,OGⅡ的降解率达到了95.81%,其降解过程符合准一级反应动力学模型,最大反应速率常数为0.0491 min-1。复合催化剂使用4次后对OGⅡ仍有68.85%的降解率。·SO_4~-、·OH和~1O_2是反应体系产生的活性氧物种,~1O_2在OGⅡ的降解中起主要作用。
语种：
中文
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