作者机构：
[Chu, Yu-Ming] Hunan City Univ, Sch Sci, Yiyang 413000, Peoples R China.;[Chu, Yu-Ming] Huzhou Univ, Dept Math, Huzhou 313000, Peoples R China.;[Rashid, Saima] Govt Coll Univ, Dept Math, Faisalabad 38000, Pakistan.;[Sultana, Sobia] Imam Mohammad Ibn Saud Islamic Univ, Dept Math, Riyadh 12211, Saudi Arabia.;[Inc, Mustafa] Firat Univ, Sci Fac, Dept Math, Elazig, Turkiye.
通讯机构：
[SAIMA RASHID; MUSTAFA INC] D;Department of Mathematics, Government College University, Faisalabad 38000, Pakistan<&wdkj&>Department of Mathematics, Science Faculty, Firat University, Elaziğ, Turkey<&wdkj&>Department of Medical Research, China Medical University, Taichung 40402, Taiwan
作者机构：
[Li, Wenguo; Deng, Yaqi; Pei, Zhengwang; Deng, YQ; Jiang, Dongchu] Hunan City Univ, Sch Informat & Elect Engn, 518 Yingbin East Rd, Yiyang 413000, Peoples R China.;[Li, Wenguo; Deng, Yaqi; Deng, YQ; Jiang, Dongchu] Hunan City Univ, All Solid State Energy Storage Mat & Devices Key L, Yiyang 413000, Peoples R China.
通讯机构：
[Deng, YQ ] H;Hunan City Univ, Sch Informat & Elect Engn, 518 Yingbin East Rd, Yiyang 413000, Peoples R China.;Hunan City Univ, All Solid State Energy Storage Mat & Devices Key L, Yiyang 413000, Peoples R China.
摘要：
In an airborne passive radar, multipath (MP) clutter, which is caused by MP signals contained in the contaminated reference signal, degrades the space-time adaptive processing (STAP) performance. The MP clutter suppression algorithm before STAP can mitigate the influence of impure reference signals. However, the performances of the existing MP clutter suppression methods deteriorate when the intrinsic clutter motion (ICM) exists because the sparse model of MP clutter is disturbed. To eliminate the impacts of ICM on MP clutter suppression, a joint optimization algorithm is developed for airborne passive radar. Firstly, the sparse model of MP clutter is modified by taking ICM fluctuation into account. Subsequently, the joint optimization function of the ICM fluctuation and MP clutter profile is derived. Finally, based on the local search technique, MP clutter is suppressed with ICM error calibration and off-grid effects mitigation. A range of simulations verify the reliability and superiority of the proposed method.
摘要：
In this study, a novel three-dimensional semi-rigid steel joint with a channel steel component is proposed, in which the channel steel component is connected to the column flange through a hybrid connection of bolts and welds along the minor axis. The design of the minor axis connection in this study had no weakening effect on the column web, and it was more convenient and easier to attach the additional channel steel component than the additional plates to the column flanges by welding. In order to investigate the static behaviour and seismic performance of the proposed novel three-dimensional semi-rigid steel joint with a channel steel component and to evaluate the interaction between both axes, numerical analyses were conducted systematically. The finite element (FE) models are firstly calibrated against the experimental results in order to get accurate results, and then the rotating characteristics, joint moment capacity, joint stiffness, ductility and energy dissipation capacity of the proposed novel semi-rigid steel joints were analysed under ten loading cases along the major and minor axes. The results indicate that the proposed novel semi-rigid steel joint has good energy dissipation capacity and deformation performance. Loading in the major-axis direction has almost no influence on the ultimate joint moment capacity but has some influence on the initial stiffness, ductility, stiffness degradation and energy dissipation ability of the proposed novel semi-rigid steel joint along the minor axis. In addition, the modified moment-rotation (M-theta) hysteretic model for the proposed novel semi-rigid steel joint is capable of effectively characterising its hysteretic behaviours, which can provide a reference for practical applications.
摘要：
International Journal of Damage Mechanics, Volume 32, Issue 9, Page 1077-1098, September 2023. <br/>Understanding the shear mechanics mechanism of bolted joints is of great significance for predicting and preventing geological disasters. Most current studies seldom consider the rheological effects of bolted joints. In this paper, a comprehensive rheological constitutive model is proposed, accounting for initial damage and damage evolution across different rheological stages and bolt characteristics. The model incorporates an elastoplastic Hooke body for instantaneous deformation, parametric nonlinear Kelvin and viscous models for attenuation and steady creep stages, and a visco-plastic model based on time-dependent shear strength for accelerated creep stage. Additionally, a bolt-rock cooperative deformation model is introduced, considering the evolution of the bolt's elastic modulus. The resulting elasto-viscoplastic constitutive model effectively describes the shear rheological behavior of bolted joints, with its validity and superiority demonstrated through comparisons with shear creep tests and the Maxwell model. This research aims to provide valuable theoretical guidance for the construction and reinforcement of rock mass engineering projects.
摘要：
In this research, the nonlinear dynamics of a clamped circular composite plate placed on a softening elastic foundation under rapid thermal loading is investigated. In this situation, based on the amount of temperature supplied to the structure and the coefficients of softening elastic foundation, two instabilities may happen one after the other. The structure will thermally buckle and deform dynamically if the applied temperature exceeds a critical level. If the softening coefficient of the elastic foundation is critical, the structure will completely lose its stability after a certain deformation range. A polymer containing graphene platelets (GPL) makes up the system. Based on various functions, the volume fraction of fillers varies along the thickness. The system's nonlinear dynamic equations are obtained by applying Hamilton's principle and the Von-Karman theory. The transient heat conduction equation is solved by the cubic B-spline collocation (CBSC) and Crank- Nicolson procedures. The CBSC and the Newmark methods are used to solve spatially and temporally dependent governing nonlinear differential equations. Also, the Newton-Raphson method is used as a powerful tool to solve nonlinear algebraic equations. The temporal evolution, phase-plane, and post-buckling-to-maximum deflection paths are demonstrated to analyze the instabilities of the plate.
期刊：
Environmental Science and Pollution Research,2023年30(14):40388-40404 ISSN：0944-1344
通讯作者：
Yang, Nan
作者机构：
[Zhao, Yunlin; Xu, Zhenggang; Mo, Wenbo] Cent South Univ Forestry & Technol, Key Lab Forestry Remote Sensing Based Big Data & E, Changsha 410004, Peoples R China.;[Yang, Nan] Hunan City Univ, Coll Architecture & Urban Planning, Lab Key Technol Digital Urban Rural Spatial Planni, Yiyang 413000, Peoples R China.;[Yang, Nan] Hunan City Univ, Hunan Prov Engn Res Ctr DongTing Lake Reg Ecol Env, Yiyang 413000, Peoples R China.
通讯机构：
[Yang, Nan] L;Laboratory of Key Technologies of Digital Urban-Rural Spatial Planning of Hunan Province, College of Architecture & Urban Planning, Hunan City University, Yiyang, 413000, China.;Hunan Provincial Engineering Research Center of DongTing Lake regional ecological enviroment intelligent monitoring and disaster prevention and mitigation technology, Hunan City University, Yiyang, 413000, China.
关键词：
Ecological functional zoning;Ecosystem service bundles;Trade-offs;Dongjiang Lake Basin
摘要：
Although the research framework of ecological function zoning is complex and diverse, there are not many spatially continuous zoning results, which can be effectively applied to watershed management practices. Ecosystem service bundles and trade-offs can identify interactions among multiple ecosystem services, and achieve better social-ecosystem management when applying to ecological function zoning. Taking the Dongjiang Lake Basin, China, as research area, the study used the InVEST model to investigate the trade-offs and synergies of ecosystem services at township and grid scales, respectively. Then, the study conducted ecological function zoning based on the bundles and trade-off intensity among ecosystem services. The results showed that food production showed extremely significant trade-offs with other services in the two scales, in which the trade-off intensity between food production and water purification was the largest, and the water areas were the hotspots of trade-off intensity. Based on the ecosystem service bundles at the township, combined with the trade-off intensity, the watershed was finally divided into four ecological functional zones, namely, agricultural product supply area (southern part in the study area), economic forestry area (northeast regions in the study area), water supply area (western areas of the study area), and forest conservation area (northern areas in the study area), accounting for 29.27%, 14.63%, 17.07%, and 39.03%, respectively. The study contributed to the ecological function maintenance and sustainable development in Dongjiang Lake Basin and provided an important reference in ecological zoning.
期刊：
JOURNAL OF ORGANIC CHEMISTRY,2023年88(20):14697-14707 ISSN：0022-3263
通讯作者：
Chen, Shanping;Deng, GJ
作者机构：
[Quan, Siying; Fang, Fang; Xia, Jie; Chen, Shanping; Deng, Guo-Jun; Chen, SP; Deng, GJ] Xiangtan Univ, Key Lab Green Organ Synth & Applicat, Key Lab Environm Friendly Chem & Applicat, Coll Chem,Minist Educ Hunan Prov, Xiangtan 411105, Peoples R China.;[Fang, Fang] Hunan City Univ, Coll Mat & Chem Engn, Yiyang 413000, Peoples R China.;[Deng, Guo-Jun; Deng, GJ] Henan Normal Univ, Sch Chem & Chem Engn, Xinxiang 453007, Peoples R China.
通讯机构：
[Chen, SP; Deng, GJ ] X;Xiangtan Univ, Key Lab Green Organ Synth & Applicat, Key Lab Environm Friendly Chem & Applicat, Coll Chem,Minist Educ Hunan Prov, Xiangtan 411105, Peoples R China.;Henan Normal Univ, Sch Chem & Chem Engn, Xinxiang 453007, Peoples R China.
摘要：
A facile and practical approach for the preparation of substituted pyrimidines from ketones, NH4OAc, and N,N-dimethylformamide dimethyl acetal has been described. This NH4I-promoted three-component tandem reaction affords a broad range of substituted pyrimidines in acceptable yields under metal- and solvent-free conditions. The present methodology features the advantages of simple and easily available starting materials, metal- and solvent-free conditions, a broad substrate scope with good functional group tolerance, and gram-scale synthesis.
摘要：
Tetracycline (TC) is an important antibiotic extensively used in livestock breeding and aquaculture, and so an effective removal strategy is urgently needed. This study explores the use of a series of hydroxyapatite calcinated at different temperatures (300, 400, 500, 600, and 700 degrees C) to activate peroxymonosulfate (PMS) for the removal of TC. The optimal conditions for the removal of 10 mg/L TC using hydroxyapatite calcinated at 600 degrees C (CHAP600) as a catalyst were determined to be: pH of 6.0, a catalyst dosage of 0.2 g/L and a PMS concentration of 0.3 mM. Under these conditions, the removal efficiency of TC reached 94 %. The potential degradation pathway of TC was proposed by identifying the intermediates using High Performance Liquid Chromatography/ Triple Quad mass spectrometry. The characterization analysis revealed that the presence of calcium carbonate on the surface of CHAP600 promoted the generation of singlet oxygen (1O2). Additionally, the phosphate group in CHAP600 served as a catalyst for the production of sulfate radicals (SO4 & BULL;-) from PMS, which subsequently react with hydroxyl or surface hydroxyl group to generate hydroxyl radicals (& BULL;OH). And the active species 1O2 is the most significant contributor to the catalytic degradation process of TC by CHAP600 activated PMS, followed by & BULL;OH, and then SO4 & BULL;-. This study provides new insight for the mechanism of removing organic contaminants using PMS activated with calcined hydroxyapatite.
摘要：
The tea plant is a vital strategic forest resource in China. Dark tea produced from its leaves is an indispensable health-promoting product in western China due to its unique lipid-lowering function. Eurotium cristatum is the dominant strain in Fuzhuan brick tea (a variety of Anhua dark tea) and could produce many functional components, including lovastatin, a lipid-lowering compound. In this study, the lovastatin yield of dark tea was improved by breeding Eurotium cristatum using the protoplast fusion method. The experiments were carried out by inducing a fusion between inactivated Eurotium cristatum JH1205 and Monascus CICC5031. Among the 92 fusants screened the HPLC method, four strains (A4, A36, A54, and A76) with higher lovastatin production (more than three times as high) were obtained. The A76 strain had the highest lovastatin yield, which was 23.93 mu g/mL. The location of the tea forest strongly influenced the lovastatin yield of loose dark tea. The strain bred in this study improved the lovastatin yield of loose dark tea by more than three times when compared to wild Eurotium cristatum. These results are promising for the development of tea forest resources.
通讯机构：
[Tianyi Chen] D;Department of Architecture, College of Design and Engineering, National University of Singapore, 4 Architecture Drive, 117566 Singapore
摘要：
Low-carbon cities (LCCs) have attracted considerable attention from researchers over the past 15 years as an important initiative for mitigating global warming. The increased pilot LCCs in several countries and focus on theoretical research suggest the need to explore the associated research topics and characteristics, trends, and challenges. An in-depth analysis of literature on LCCs was conducted using the three-phase research involving documents searching, quantitative analyses and qualitative analyses. The quantitative analysis revealed that nearly 70% of LCC research was conducted in three countries. The results of the quantitative analysis also generated a map of term clusters, which identified the 9 major areas. A qualitative analysis of the literature indicated that transition to low-carbon energy is the most intensively researched category, and LCC planning and design dominates the research field. Based on the results of the quantitative and qualitative analyses, this study reports knowledge gaps in the literature and proposes future directions for LCC research in the context of four major trends: LCC planning and design, low-carbon energy transition, low-carbon decision support, and low-carbon management and policy. This study improves the existing knowledge on LCC-related research and pro-vides a future guidance for theoretical research and pilot practices related to LCC.
摘要：
Though building-scale energy demand and indoor thermal comfort have been extensively covered by recent studies, the automation of middle- and larger-scale outdoor microclimate evaluation in parametric design is less covered. The relatively slow computation and the need for sophisticated expertise are some of the current issues. This paper proposes a Rhino–Grasshopper custom script to automatically compute spatial indicators for a quick thermal comfort estimation. The Galapagos evolutionary algorithm is used to optimize thermal comfort and select the best combinations of spatial indicators. In a summer case study located in Shantou, China, the proposed workflow was three times faster than a non-automated indicator calculation in ArcGIS, while the optimization method achieved 25% to 33% reduction in land areas under extreme heat stress. This automated process applies to existing states and new urban designs. It is adaptable to customized prediction models under different climatic zones.
作者机构：
[Tang, Hui; Ao, Rongjun; Zhou, Xiaoqi; Aihemaitijiang, Yierfanjiang; Chen, Jing] Cent China Normal Univ, Key Lab Geog Proc Anal & Simulat Hubei Prov, Wuhan, Hubei, Peoples R China.;[Tang, Hui; Ao, Rongjun; Zhou, Xiaoqi; Aihemaitijiang, Yierfanjiang; Chen, Jing] Cent China Normal Univ, Coll Urban & Environm Sci, Wuhan, Hubei, Peoples R China.;[Tang, Hui] Hunan City Univ, Sch Architecture & Urban Planning, Yiyang, Hunan, Peoples R China.
通讯机构：
[Aihemaitijiang, Y ] C;Cent China Normal Univ, Key Lab Geog Proc Anal & Simulat Hubei Prov, Wuhan, Hubei, Peoples R China.;Cent China Normal Univ, Coll Urban & Environm Sci, Wuhan, Hubei, Peoples R China.
摘要：
High-quality regional development should be promoted by facilitating inter-regional mobility of heterogeneous labor force to optimize its spatial allocation. This study incorporates skill relatedness into spatial categorization and selection effects, and explores how skill-relatedness affects the location choice of heterogeneous labor force. To do so, we use labor force migration data and employee data by occupation subcategory from the 2000 National Population Census and 2015 National Population Sample Survey. The empirical evidence provides three major findings. First, there are significant regional differences in labor migration rates by the occupational group between cities in China, and the trend is increasing. Regional concentration of location choice is increasing and six significant agglomerations are formed. Second, skill relatedness positively affects the location choice of the heterogeneous labor force in Chinese cities. When cities' skill-relatedness is more robust, influence on labor location choice is more remarkable. In cities with high-size classes, the effect of high-skill relatedness on labor location choice is higher. Third, labor force with solid skill relatedness with regional employment moves to the location owing to the spatial sorting effect. Labor force without skill relatedness or weak relatedness moves out or does not move to the location owing to the spatial selection effect.
期刊：
Journal of Manufacturing Processes,2023年101:795-806 ISSN：1526-6125
通讯作者：
Cui, JJ
作者机构：
[Li, Guangyao; Cui, JJ; Zhu, Jiapei; Cui, Junjia; Chen, Chang; Jiang, Hao; Liu, Quanxiaoxiao] Hunan Univ, State Key Lab Adv Design & Mfg Technol Vehicle, Changsha 410082, Peoples R China.;[Chen, Chang] Hunan City Univ, Sch Mech & Elect Engn, Yiyang 413000, Peoples R China.;[Li, Guangyao] Beijing Inst Technol, Shenzhen Automot Res Inst, Shenzhen Res Inst, Natl Engn Lab Elect Vehicles, Shenzhen 518118, Peoples R China.
通讯机构：
[Cui, JJ ] H;Hunan Univ, State Key Lab Adv Design & Mfg Technol Vehicle, Changsha 410082, Peoples R China.
关键词：
Magnetic pulse spot welding;Aluminium alloy sheet;Mechanical property;Micro-morphology
摘要：
Magnetic pulse spot welding (MPSW) is a safe, efficient and environmentally friendly process, which is very suitable for joining aluminium alloys. AA5052 aluminium alloy sheets were joined by MPSW. Specifically, the bump on the flyer plate was driven to impact the parent plate at high velocity to achieve metallurgical bonding. The formation process, mechanical properties and micro-morphology of the joint were studied. The results showed that the bump of the flyer plate impacted the parent plate at high velocity caused by Lorentz force to form welding seam. The shape of the welding seam was two incompletely continuous symmetrical elliptical arcs due to the different welding velocities and welding angles in each zone. The strength of the joint was higher than that of the base metal at appropriate process parameters. Specifically, the relatively better process parameters were welding gap of 1.4 mm, welding diameter of 16 mm and discharge energy of 36 kJ. The maximum loads of tensile shear and cross-tension were 4887 N, 1744 N. There were a large amount of dimples at the fracture of welding seam, and the toughness of joint was good.
作者机构：
[Ge, Yaping; Tang, Huang; Yang, Yiming; Li, Hai] Hunan City Univ, Hunan Engn Res Ctr Dev & Applicat Ceramsite Concre, Yiyang 413000, Peoples R China.;[Tang, Huang] Changsha Univ Sci &Technol, Key Lab Safety Control Bridge Engn Minist Educ, Changsha 410114, Peoples R China.;[Xiao, Linfa] East China Jiaotong Univ, Sch Transportat Engn, Nanchang 330013, Jiangxi, Peoples R China.
通讯机构：
[Yang, YM ] H;Hunan City Univ, Hunan Engn Res Ctr Dev & Applicat Ceramsite Concre, Yiyang 413000, Peoples R China.
关键词：
Chloride salt erosion;Freeze-thaw cycle;Interface shear strength;Self-compacting concrete
摘要：
Self-compacting concrete (SCC) has been widely used for concrete jacketing to strengthen RC structures due to its high workability, fluidity, and segregation resistance. In this study, a test was carried out to study the effects of substrate curing including chloride salt erosion and the freeze–thaw cycle on the interface shear strength between ordinary concrete and the SCC. Eighty-four Z-type specimens were designed and tested through direct shear experiments, and the influence of interface treatment (implanting steel bar and cutting groove), concrete type, and substrate curing on the interface shear strength were analyzed. Four calculation models of interface shear strength based on different codes are compared, the applicability of these models is also analyzed. The results show that: For close the substrate concrete and the SCC strength, the effect of chloride salt erosion and freeze–thaw cycle will cause a slight decrease in the interface shear strength compared with the specimen that substrate is not cured, the influence of chloride ion erosion and freeze–thaw cycle on the degeneration of interface shear strength for specimen with implanting steel bar is not more obviously than specimen with cutting groove. Any single code model can not accurately predict the interface shear strength of all specimens with different interface treatments and substrate curing. The fib model can accurately predict interface shear strength of specimens which the average compressive strength of old and new concrete is less than 40 MPa and the substrate is not cured. Whether the substrate is cured or not, EC2 and CSA A23.3–14 models can quite accurately predict the interface shear strength of specimens with an implanting steel bar, but for specimens with cutting groove, the modified AASHTO model can accurately predict the interface shear strength. Except modified AASHTO model, the factor considering the effect of interface treatment should be taken into account when using fib, EC2 and CSA A23.3–14 models to calculate the interface shear strength.
摘要：
In recent years, the provision of applications based on conferencing services over Software-Defined Networking (SDN) is increasing. So far, extensive studies have been conducted on improving conferencing services and supporting high-quality communication in SDN, and the importance of the issue has been understood by the research society. One of the challenges of guaranteeing conferencing services in SDN is the routing of network traffic taking into account Quality of Service (QoS) requirements. Most routing techniques in SDN guarantee end-to-end delay and bandwidth constraints. However, resource loss also plays a role in network performance, where it is clearly neglected in existing works. This study presents a guaranteed Latency-Bandwidth-Loss Routing algorithm based on Fuzzy approach to improve the performance of conference services in SDN (LBLRF). The purpose of the fuzzy-based approach is to increase the number of routed requests and improve the performance of conference services in SDN. LBLRF uses a postponement mechanism to improve the conference service, where it gives higher priority to the requests with low resource demand for connection. In addition, LBLRF is equipped with a hold time mechanism to release the reserved resources after satisfying the request requirements. This mechanism can increase the processing capacity of future requests by conserving network resources. Evaluations have been done by defining several scenarios on a synthetic SDN environment. The results of the experiments show that LBLRF provides a better request acceptance rate between 7% and 16% compared to the best results of existing algorithms.
摘要：
Sulfur dioxide (SO(2)) derivatives are extensively utilized as both a preservative for foods and an active gaseous signal molecule in various physiological and pathological processes, but their excessive intake would bring harmful effects on human health; so, the determination of SO(2) derivatives is of great importance. Herein, we developed a ratiometric fluorescent probe named 2-(2'-hydroxyphenyl)benzothiazole-3-ethyl-1,1,2-trimethyl-1H-benzo[e]indolium (HBT-EMBI) by introducing a hemicyanine unit of EMBI to an HBT group for the detection of SO(2) derivatives via an excited-state intramolecular proton transfer (ESIPT) and intramolecular charge transfer (ICT) effects. The probe displays some advantages, such as a colorimetric change from purple to colorless, a ratiometric fluorescence with zero cross-talk, and a remarkably large emission shift (Δλ = 164 nm) under a single-wavelength excitation. Accordingly, the probe HBT-EMBI has been successfully employed for the colorimetric and ratiometric determination of SO(2) derivatives in real food samples and the quantitative visualization of SO(2) derivative variations in HepG2 cells.
摘要：
BiCuSeO compound is a promising thermoelectric material, which has attracted many experimental stud-ies through trial-and-error approaches to improve its thermoelectric performance by element doping, such that a fast and efficient prediction of thermoelectric property for unexplored and rarely explored doped-BiCuSeO is highly desired. In this work, a machine learning (ML) model for predicting the ZT value of M element doped-BiCuSeO (Bi1-xMxCuSeO) has been established via the correlation analysis for descriptors and the comparison among different ML approaches. The results show that Gradient Boosting Regressor is the most appropriate approach for our ML model, which is well validated by com-paring the predicted and experimental ZT values for the cases in the dataset. The ML model is also used to predict the ZT values of Bi1-xMxCuSeO with unexplored and rarely explored doping element M, and the optimal doping elements as well as their doping contents are screened out. The results indicate that the ZT of Bi0.86Po0.14CuSeO (Po-doped) and Bi0.88Cs0.12CuSeO (Cs-doped) are higher than that of pure BiCuSeO, and are improved by 104 % and 98 % at the 923 K, respectively. The enhancement is well explained by the first-principles calculations. The findings offer a guideline for exploring superior ther-moelectric performance in BiCuSeO.(c) 2023 The Author(s). Published by Elsevier Ltd. This is an open access article under the CC BY-NC-ND license (http://creativecommons.org/licenses/by-nc-nd/4.0/).
关键词：
Viscoelastic fluid;Activation energy;Stagnation point flow;Heat generation/absorption;Generalized Fourier and Fick ' s law;Stretching sheet
摘要：
This analysis describes the stagnation point and mixed convection flow of a viscoelastic micropolar fluid into a porous medium towards a stretchable sheet and magnetic field. Concentration and thermal stratification boundary conditions and activation energy are studied. For the flow of heat and mass transportation, Fourier and Fick's law is also accommodated into account. Suitable similarity variables are utilized to attain the dimen-sionless form of the governed equations. These dimensionless equations have been resolved numerically with the help of BVP4C approach. The velocity profile is reduced with the stronger estimations of eand M. The coefficient of skin friction has an increasing effect by improving values of K, fi, M, and SMALL ELEMENT OF. The velocity sketch has the opposite behavior for SMALL ELEMENT OF and fit. Stronger estimations of fi and Se lead to the decay of the temperature profile. The angular velocity of the fluid upsurges due to the stronger values of K.
作者机构：
[Peng, Zhigao; Peng, ZG; Feng, Haoxiong; Xiao, Ming] Hunan City Univ, Coll Civil Engn, Yiyang 413000, Peoples R China.;[Peng, Zhigao; Peng, ZG] Hunan City Univ, Hunan Engn Res Ctr Struct Safety & Disaster Preven, Yiyang 413000, Hunan, Peoples R China.;[Liu, Shenggui] Univ Min & Technol Beijing, Sch Mech & Civil Engn, Beijing 100083, Peoples R China.;[Long, Yanqing] Hunan Tunnel Engn Co LTD, Yiyang 413000, Peoples R China.
通讯机构：
[Peng, ZG ] H;Hunan City Univ, Coll Civil Engn, Yiyang 413000, Peoples R China.;Hunan City Univ, Hunan Engn Res Ctr Struct Safety & Disaster Preven, Yiyang 413000, Hunan, Peoples R China.
摘要：
The occurrence of coalbed methane adsorption-desorption hysteresis has been widely observed, but a unified understanding of its mechanism is lacking, and the factors affecting its degree are unclear. This study introduces a microscale LB model for gas diffusion-adsorption-desorption in porous media that also accounts for the adsorption-desorption hysteresis effect. The accuracy of the model has been validated using previous experimental data, and the primary controlling factors of adsorption-desorption hysteresis were analyzed. The findings are as follows: (1) In the process of methane diffusion-adsorption-desorption, Knudsen diffusion dominates in micro- and mesopores, while viscous flow prevails in macropores; our model can adaptively adjust gas transport regimes across a broad range of pore sizes and pressures. (2) The desorption amount and rate are close relative to the correction factors α and β. A higher α value corresponds to greater initial adsorption as well as longer desorption time, whereas a lower β value implies weaker desorption capacity and a slower desorption rate. (3) Pore size can affect gas diffusion-adsorption-desorption kinetics, where larger pore size corresponds to efficient gas diffusivity; when r < 10 nm, the desorption process is mainly controlled by the desorption rate. Overall, this study has offered new insights into the mechanism behind methane adsorption-desorption hysteresis at the microscale, identified primary controlling factors of methane diffusion-adsorption-desorption process, and provided a foundation for numerical simulations and experiments related to the adsorption-desorption hysteresis.
