检索结果-南通市图书馆

Remediation of di(2-ethylhexyl)phthalate(DEHP)contaminated black soil by freeze-thaw aging biochar

在线全文

学校读者我要写书评

暂无评论

Journal of Environmental Sciences 2024年第1期135卷 681-692页

作者： Lei Wang Zeyu Dou Chaoran Ma Xiaochen Jia Hongye Wang Wenjing Bao Lei Wang Jianhua Qu Ying Zhang school of resources and Environment Northeast Agricultural UniversityHarbin 150030China

Di(2-ethylhexyl)phthalate(DEHP),a complex structure with high toxicity,is a common organic *** study investigated the effects of fresh biochar(FBC),and freeze-thaw cycled aged biochar(FTC-BC)on DEHP-contaminated soils using a pot *** specific surface area of FBC increased from 145.20 to 303.50 m~2/g,and oxygen-containing functional groups increased from 1.26 to 1.48 mol/g after freeze-thaw cycles,greatly enhancing the adsorption of DEHP by biochar in the *** comprehensive radar chart evaluation showed that FBC and FTC-BC reduced DEHP growth stress and improved the soil *** with FBC,FTC-BC performed better in protecting the normal growth of pakchoi and improving soil *** addition,the application of biochar increased the diversity and abundance of bacteria in the DEHP-contaminated soil and changed the composition of the soil bacterial *** partial least squares path model(PLS-PM)showed that adding biochar as a soil remediation agent significantly positively impacted soil nutrients and indirectly reduced the DEHP levels in soil and plants by increasing soil microbial *** with FBC,FTC-BC creates a more satisfactory living environment for microorganisms and has a better effect on the degradation of DEHP in the *** study provides a theoretical basis for future biochar remediation of DEHP-contaminated soils in cold high-latitude regions.

关键词： DEHP Freeze-thaw cycles Biochar Soil restoration

Precise separation and efficient recovery of Pd(Ⅱ) from high-level liquid waste by XAD-based adsorbents

在线全文

学校读者我要写书评

暂无评论

Rare Metals 2024年第10期43卷 5372-5390页

作者： Hao-Ran Dong Shun-Yan Ning Zeng-Yuan Li Si-Zhi Xu Feng-Tao Hu Feng Gao You-Bin Wang Li-Feng Chen Xiang-Biao Yin Toyohisa Fujita Mohammed F.Hamza Yue-Zhou Wei school of resources Environment and MaterialsGuangxi University school of Nuclear Science and Technology University of South China

Efficient separation of palladium (Pd（II）) from high-level liquid waste （HLLW） not only helps the safe disposal of nuclear waste,but also is a vital importan supplement to Pd（II） ***,16 kinds of nove Amberlite XAD resins-based adsorbents were prepared by vacuum impregnation method for the separation of Pd（II）from simulated HLLW,and the MMBT/XAD7HP prepared using 4-methyl-2-mercaptobenzothiazole （MMBT） as ligand and Amberlite XAD7HP resin （XAD7HP） as the carrier was selected as the optimal research *** analysis experiments proved the successful preparation of MMBT/XAD7HP,which exhibited ultrahigh adsorption selectivity for Pd（II）(distribution coefficient （Kd）≥12584.5 ml·g-1,separation factor (SFPd/M)≥2818.4) and superior adsorption capacity(Q≥130.1 mg·g-1).The adsorption kinetics and adsorption isotherms for Pd（II） matched with pseudo-secondorder （PSO） kinetics model and Langmuir model,indicating that the adsorption mode for Pd（II） by MMBT/XAD7 HP was monolayer chemical *** dynamic column experiments showed that MMBT/XAD7 HP achieved efficiently separation of Pd（II） from simulated HLLW,and the recovery rate was nearly 100% The adsorption mechanism was analyzed by Fourier transform infrared spectroscopy （FTIR）,X-ray photoelectron spectroscopy （XPS） and density functional theory（DFT）,and the ultrahigh selectivity of MMBT/XAD7 HP is attributed to the preferred affinity of the soft-N,S donor atoms in MMBT for Pd（II）.MMBT has the shortest frontline molecular orbital energy band gap （HOMO–LUMO） among the four ligands,which makes it easier to become an electron donor to attract Pd2+to participate in ***3-participates in the adsorption to keep charge *** summary,MMBT/XAD7 HP has broad application prospects for the treatment of Pd（II） in HLLW

关键词： Adsorption Column experiments HLLW Palladium XAD

Impact and mechanism of bisphosphonate depressant 1-hydroxypropane-1,1-diphosphonic acid on flotation decalcification of dolomite-rich magnesite ore

在线全文

同方期刊数据库

学校读者我要写书评

暂无评论

International Journal of Mining Science and Technology 2024年第7期34卷 1017-1032页

作者： Wengang Liu Xudong Chen Wenbao Liu Naixu Zhang Yong Mao Ying Guo school of resources&Civil Engineering Northeastern UniversityShenyang 110819China

Given the depletion of high-quality magnesite deposits and the rising demand for high-end magnesium materials,the separation and utilization of high-calcium magnesite ores have become ***,the similar surface properties and solubility of semi-soluble salt-type minerals,pose significant challenges for the utilization of dolomite-rich magnesite *** this study,1-hydroxypropane-1,1-di phosphonic acid(HPDP)was identified for the first time as a high-performance depressant for *** tests,including contact angle measurements,ζ potential analysis,X-ray photoelectron spectroscopy,and atomic force microscopy,were conducted to elucidate the interfacial interaction mechanisms of HPDP on the surfaces of the two minerals at different ***,molecular modeling calculations were used to detail the spatial matching relationship between HPDP and the crystal faces of the two *** was emphasized that HPDP specifically adsorbed onto the dolomite surface by forming calcium phosphonate,ensuring that the dolomite surface remained hydrophilic and ***,it was found that the adsorption strength of HPDP on the mineral surfaces depended on the activity of the metal sites and their spatial *** findings provide a theoretical foundation for the molecular design of flotation reagents for high-calcium magnesite ores.

关键词： Depressant Interfacial mechanism Magnesite Dolomite DFT Decalcification

Study of the pressure transient behavior of directional wells considering the effect of non-uniform flux distribution

在线全文

学校读者我要写书评

暂无评论

Petroleum Science 2024年第3期21卷 1765-1779页

作者： Yan-Zhong Liang Bai-Lu Teng Wan-Jing Luo school of Energy resources China University of Geosciences(Beijing)Beijing100083China

During the production,the fluid in the vicinity of the directional well enters the wellbore with different rates,leading to non-uniform flux distribution along the directional ***,in all existing studies,it is oversimplified to a uniform flux distribution,which can result in inaccurate results for field ***,this paper proposes a semi-analytical model of a directional well based on the assumption of non-uniform flux ***,the direction well is discretized into a carefully chosen series of linear sources,such that the complex well trajectory can be captured and the nonuniform flux distribution along the wellbore can be considered to model the three-dimensional flow *** using the finite difference method,we can obtain the numerical solutions of the transient flow within the *** the aid of Green's function method,we can obtain the analytical solutions of the transient flow from the matrix to the *** complete flow behavior of a directional well is perfectly represented by coupling the above two types of transient ***,on the basis of the proposed model,we conduct a comprehensive analysis of the pressure transient behavior of a directional *** computation results show that the flux variation along the direction well has a significant effect on pressure *** addition,the directional well in an infinite reservoir may exhibit the following flow regimes:wellbore afterflow,transition flow,inclined radial flow,elliptical flow,horizontal linear flow,and horizontal radial *** horizontal linear flow can be observed only if the formation thickness is much smaller than the well ***,a dip region that appears on the pressure derivative curve indicates the three-dimensional flow behavior near the wellbore.

关键词： Directional well Pressure transient behavior Semi-analytical model Non-uniform flux

Hybrid stacking ensemble algorithm and simulated annealing optimization for stability evaluation of underground entry-type excavations

在线全文

学校读者我要写书评

暂无评论

Underground Space 2024年第4期17卷 25-44页

作者： Leilei Liu Guoyan Zhao Weizhang Liang Zheng Jian school of resources and Safety Engineering Central South UniversityChangsha 410083China

The stability of underground entry-type excavations(UETEs)is of paramount importance for ensuring the safety of mining *** more engineering cases are accumulated,machine learning(ML)has demonstrated great potential for the stability evaluation of *** this study,a hybrid stacking ensemble method aggregating support vector machine(SVM),k-nearest neighbor(KNN),decision tree(DT),random forest(RF),multilayer perceptron neural network(MLPNN)and extreme gradient boosting(XGBoost)algorithms was proposed to assess the stability of ***,a total of 399 historical cases with two indicators were collected from seven ***,to pursue better evaluation performance,the hyperparameters of base learners(SVM,KNN,DT,RF,MLPNN and XGBoost)and meta learner(MLPNN)were tuned by combining a five-fold cross validation(CV)and simulated annealing(SA)*** on the optimal hyperparameters configuration,the stacking ensemble models were constructed using the training set(75%of the data).Finally,the performance of the proposed approach was evaluated by two global metrics(accuracy and Cohen’s Kappa)and three within-class metrics(macro average of the precision,recall and F1-score)on the test set(25%of the data).In addition,the evaluation results were compared with six base learners optimized by *** hybrid stacking ensemble algorithm achieved better comprehensive performance with the accuracy,Kappa coefficient,macro average of the precision,recall and F1-score were 0.92,0.851,0.885,0.88 and 0.883,*** rock mass rating(RMR)had the most important influence on evaluation ***,the critical span graph(CSG)was updated based on the proposed model,representing a significant improvement compared with the previous *** study can provide valuable guidance for stability analysis and risk management of ***,it is necessary to consider more indicators and collect more extensive and balanced dataset to validate the model in futur

关键词： Underground entry-type excavations(UETEs) Hybrid stacking ensemble Machine learning Simulated annealing Critical span graph Base and meta learners

Novel rockburst prediction criterion with enhanced explainability employing CatBoost and nature-inspired metaheuristic technique

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Underground Space 2024年第6期19卷 101-118页

作者： Yingui Qiu Jian Zhou school of resources and Safety Engineering Central South UniversityChangsha 410083China

Rockburst is a major challenge to hard rock engineering at great *** and timely assessment of rockburst risk can avoid unnecessary casualties and property *** the existence of various methods for rockburst assessment,there remains an urgent need for a comprehensive and reliable criterion that is easy to both apply and *** a new rockburst criterion based on simple parameters can potentially fill this *** its advantages,this criterion can facilitate a more effective and efficient prediction of rockburst potential,thereby contributing significantly to enhancing safety *** this paper,combined with the internal and external factors of rockburst,four control variables(i.e.,integrity index,stress index,brittleness index,and elastic energy index)were selected to be incorporated into a comprehensive rockburstability index(RBSI).Based on 116 sets of rockburst cases,the rockburst potential was accurately quantified and predicted using the categorical boosting(CatBoost)model and the nature-inspired metaheuristic African vultures optimization algorithm(AVOA).In its performance validation,the criterion achieved the highest accuracy of 90.48%,verifying the reliability and effectiveness of the proposed RBSI ***,an interpretive method was applied to analyze the variable influence on the criterion,facilitating the explanation of predictions and the analysis of the formula’s robustness under different *** general,compared with existing criterion methods involving relevant indicators,the newly proposed RBSI criterion enhances the accuracy of rockburst potential prediction,and it can effectively and swiftly evaluate the preliminary risk of ***,a graphical user interface was developed to provide a clear visualization of the assessment of rockburst potential.

关键词： Rockburst criterion CatBoost Metaheuristic optimization Model interpretation Graphical user interface

Numerical simulation of microwave-induced cracking and melting of granite based on mineral microscopic models

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

International Journal of Minerals,Metallurgy and Materials 2024年第7期31卷 1512-1524页

作者： Xiaoli Su Diyuan Li Junjie Zhao Mimi Wang Xing Su Aohui Zhou school of resources and Safety Engineering Central South UniversityChangsha 410083China

This study introduces a coupled electromagnetic–thermal–mechanical model to reveal the mechanisms of microcracking and mineral melting of polymineralic rocks under microwave *** tests validate the rationality of the proposed *** microscopic mineral sections into the granite model for simulation shows that uneven temperature gradients create distinct molten,porous,and nonmolten zones on the fracture ***,the varying thermal expansion coefficients and Young's moduli among the minerals induce significant thermal stress at the mineral *** and biotite with higher thermal expansion coefficients are subjected to compression,whereas plagioclase with smaller coefficients experiences tensile *** the molten zone,quartz undergoes transgranular cracking due to theα–βphase *** local high temperatures also induce melting phase transitions in biotite and *** numerical study provides new insights into the distribution of thermal stress and mineral phase changes in rocks under microwave irradiation.

关键词： microwave numerical modeling microcracking phase change granite

Gravel hardness effect on compaction characteristics of gravelly soil

在线全文

学校读者我要写书评

暂无评论

Journal of Mountain Science 2024年第4期21卷 1432-1443页

作者： SHI Yunfang LI Shengang JIANG Chen LIU Jinning school of resources and Civil Engineering Northeastern UniversityShenyang 110004China

The compaction characteristics of gravelly soil are affected by gravel *** investigate the evolution and influencing mechanism of different gravel hardness on the compaction characteristics of gravelly soil,heavy compaction tests and crushing tests were conducted on gravelly soils with gravels originated from hard,soft and extremely soft *** to orthogonal experiments and variance analysis,it was found that hardness has a significant impact on the maximum dry density of gravelly soil,followed by gravel content,and lastly,moisture *** gravel compositions with an average saturated uniaxial compressive strength less than 60 MPa,the order of compacted maximum dry density is soft gravels>hard gravels>extremely soft *** type of gravelly soil has a threshold for gravel content,with 60%for hard and soft gravels and 50%for extremely soft *** these thresholds,the compacted dry density decreases *** is a certain interaction between hardness,gravel content,and moisture *** hardness increases the influence of gravel content,whereas lower hardness increases the influence of moisture *** soils with the coarse aggregate(CA)between 0.7 and 0.8 typically achieve higher dry densities after *** addition,the prediction equations for the particle breakage rate and CA ratio in the Bailey method were proposed to estimate the compaction performance of gravelly soil *** results further revealed the compaction mechanism of different gravelly soils and can provide reference for subgrade filling construction.

关键词： Gravelly soil Hardness Compaction characteristics Crushing characteristics Particle breakage rate Bailey method

Research on Modeling and Parameter Identification of Comprehensive Load Model of Distribution Network in Industrial Park

在线全文

学校读者我要写书评

暂无评论

Chinese Journal of Electronics 2024年第1期33卷 264-273页

作者： Tingling WANG Xiaohe YAN school of Electric Engineering North China University of Water Resources and Electric Power Wenzhou Polytechnic

With the rapid development of industrial parks, its load model research has become a hot spot. In order to study the load of power system in industrial park, based on the characteristics of the industrial park load, a comprehensive load admittance static model with full voltage range adaptability is considered, and a comprehensive load model of distribution network of the industrial park is established. A complete parameter identification of the model is carried out through chaos particle swarm optimization. The simulation results show that the model can effectively describe the load characteristics of the distribution network in industrial parks.

关键词： Chaos Adaptation models Analytical models Parameter estimation Induction motors Simulation Distribution networks