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学者姓名：周剑
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摘要 ：
As anthropogenic antibiotics, quinolones, e.g., ofloxacin have adverse impacts on ecological systems and human heaths. The removal of quinolones is of great importance, and adsorption techniques have been widely used to remove this hazardous contaminant. However, a robust and easy-operating adsorbent is still emergently required due to the complex chemical structure of quinolones. In this study, we successfully synthesized the promising metallic carbons (MCs) containing carbon nanotubes and cobalt nanoparticles by carbonizing Zn/Co-ZIF at 900 degrees C. Three different molar ratios of Co and Zn were applied to optimize the adsorption capacity on ofloxacin (OFL). Results showed MC with molar ratio of Co and Zn at 3:1 (Co-CNT/NPC3/1) achieved the maximal adsorption capacity to 118.3 mg g-1. Its adsorption performance was satisfied in the pH range from 5 to 9 and ionic strengths at 0.01 M. The main mechanisms for these adsorptions were identified as electrostatic attraction, metal coordination and pi-pi EDA. Removal efficiencies of quinolones higher than 68 mg g-1 indicated the strong feasibility of this adsorbent for wastewater treatments. The regeneration of Co-CNT/NPC3/1 at 600 degrees C allowed its at least 4-time reusability and its magnetic property enabled external magnets to recycle it from real environments.
关键词 ：
Magnetic separation Magnetic separation Adsorption Adsorption Zn Zn Co zeolitic imidazolate frameworks Co zeolitic imidazolate frameworks Metallic carbides Metallic carbides
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| GB/T 7714 | Liang, Yixuan , Zhang, Qiyu , Li, Sumei et al. Highly efficient removal of quinolones by using the easily reusable MOF derived-carbon [J]. | JOURNAL OF HAZARDOUS MATERIALS , 2022 , 423 . |
| MLA | Liang, Yixuan et al. "Highly efficient removal of quinolones by using the easily reusable MOF derived-carbon" . | JOURNAL OF HAZARDOUS MATERIALS 423 (2022) . |
| APA | Liang, Yixuan , Zhang, Qiyu , Li, Sumei , Fei, Jiaying , Zhou, Jian , Shan, Saisai et al. Highly efficient removal of quinolones by using the easily reusable MOF derived-carbon . | JOURNAL OF HAZARDOUS MATERIALS , 2022 , 423 . |
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摘要 ：
岩体工程计算分析中结构面刚度系数是至关重要的力学参数,计算分析的精度和可靠程度与这个参数密不可分,结构面刚度系数取值仍然是一个难点.岩体中应力波传播至结构面处将会发生反射和透射现象,利用应力波透射系数可反演结构面动态刚度系数.本文从细观力学角度运用颗粒离散元方法,开发分段线性接触模型及应力波吸收边界模型,开展宏观岩体中应力波传播的模拟,结合准静态压缩试验模拟,研究了较为平直的岩体结构面分别在不同正应力条件下的动、静态刚度系数的变化特征.模拟结果表明:(1)利用C++语言开发的分段线性接触模型很好地实现了结构面非线性变形特征的模拟;(2)基于颗粒离散元方法能够准确地反映岩体中应力波传播规律,应力波通过不同刚度结构面的透射系数与理论解一致;(3)在离散颗粒模型中加入黏滞吸收边界条件很好地实现了在有限尺寸模型中远场应力波传播模拟;(4)在岩体模型中结构面接触部位运用分段线性接触模型,通过模拟应力波传播与单轴压缩试验分别获得了一致性较好的结构面动、静态刚度系数,结构面动/静态刚度系数之比值约为1.0.本文对岩体中结构面刚度的测试和取值具有重要的指导意义.
关键词 ：
黏结颗粒模型 黏结颗粒模型 吸收边界模型 吸收边界模型 结构面刚度系数反演 结构面刚度系数反演 接触模型 接触模型 应力波传播 应力波传播
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| GB/T 7714 | 周剑 , 王彦兵 , 张路青 et al. 基于离散颗粒模型的岩体结构面动-静态刚度系数对比的数值模拟研究 [J]. | 工程地质学报 , 2021 , 29 (1) : 25-33 . |
| MLA | 周剑 et al. "基于离散颗粒模型的岩体结构面动-静态刚度系数对比的数值模拟研究" . | 工程地质学报 29 . 1 (2021) : 25-33 . |
| APA | 周剑 , 王彦兵 , 张路青 , 金永军 , 涂新斌 . 基于离散颗粒模型的岩体结构面动-静态刚度系数对比的数值模拟研究 . | 工程地质学报 , 2021 , 29 (1) , 25-33 . |
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摘要 ：
基于离散颗粒模型的岩体结构面动-静态刚度系数对比的数值模拟研究
关键词 ：
黏结颗粒模型 黏结颗粒模型 吸收边界模型 吸收边界模型 结构面刚度系数反演 结构面刚度系数反演 接触模型 接触模型 应力波传播 应力波传播
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| GB/T 7714 | 周剑 , 王彦兵 , 张路青 et al. 基于离散颗粒模型的岩体结构面动-静态刚度系数对比的数值模拟研究 [J]. | 周剑 , 2021 , 29 (1) : 25-33 . |
| MLA | 周剑 et al. "基于离散颗粒模型的岩体结构面动-静态刚度系数对比的数值模拟研究" . | 周剑 29 . 1 (2021) : 25-33 . |
| APA | 周剑 , 王彦兵 , 张路青 , 金永军 , 涂新斌 , 工程地质学报 . 基于离散颗粒模型的岩体结构面动-静态刚度系数对比的数值模拟研究 . | 周剑 , 2021 , 29 (1) , 25-33 . |
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摘要 ：
本文研究了硫铝酸盐水泥(CSA)在盐酸和硫酸环境下的力学性能演化规律,并探究了其抗酸侵蚀机理.分别测试了水和酸溶液养护的CSA胶砂试件的抗折强度,计算了CSA的抗酸侵蚀系数.采用XRD、TGA、CT和SEM分析了酸侵蚀导致的产物种类和数量变化,表征了微观结构演化过程.结果表明:与普通硅酸盐水泥(OPC)相比,CSA在盐酸和硫酸中抗折强度损失率更低,具有更好的抗盐酸和硫酸侵蚀能力;CSA主要水化产物(钙矾石)比OPC主要水化产物(氢氧化钙和硅酸钙凝胶)更难与酸反应,因此抗酸侵蚀能力更强.盐酸与硫酸对CSA的侵蚀机制略有不同,盐酸对CSA的侵蚀过程实质上为氢离子对CSA水化产物钙矾石的酸解,硫酸对CSA的侵蚀则是氢离子和硫酸根离子的共同作用.
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| GB/T 7714 | 齐秋霖 , 周健 , 葛仲熙 et al. 硫铝酸盐水泥抗酸侵蚀性能与机理研究 [J]. | 硅酸盐通报 , 2021 , 40 (8) : 2508-2514,2533 . |
| MLA | 齐秋霖 et al. "硫铝酸盐水泥抗酸侵蚀性能与机理研究" . | 硅酸盐通报 40 . 8 (2021) : 2508-2514,2533 . |
| APA | 齐秋霖 , 周健 , 葛仲熙 , 李辉 , 徐名凤 , 陈智丰 et al. 硫铝酸盐水泥抗酸侵蚀性能与机理研究 . | 硅酸盐通报 , 2021 , 40 (8) , 2508-2514,2533 . |
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摘要 ：
Despite numerous inherent merits of metal-organic frameworks (MOFs), structural fragility has imposed great restrictions on their wider involvement in many applications, such as in catalysis. Herein, a strategy for enhancing stability and enabling functionality in a labile Zr(IV)-MOF has been proposed by in situ porphyrin substitution. A size- and geometry-matched robust linear porphyrin ligand 4,4'-(porphyrin-5,15-diyl)dibenzolate (DCPP2- ) is selected to replace the 4,4'-(1,3,6,8-tetraoxobenzo[lmn][3,8]phenanthroline-2,7(1H,3H,6H,8H)-diyl)dibenzoate (NDIDB2- ) ligand in the synthesis of BUT-109(Zr), affording BUT-110 with varied porphyrin contents. Compared to BUT-109(Zr), the chemical stability of BUT-110 series is greatly improved. Metalloporphyrin incorporation endows BUT-110 MOFs with high catalytic activity in the photoreduction of CO2 , in the absence of photosensitizers. By tuning the metal species and porphyrin contents in BUT-110, the resulting BUT-110-50%-Co is demonstrated to be a good photocatalyst for selective CO2 -to-CO reduction, via balancing the chemical stability, photocatalytic efficiency, and synthetic cost. This work highlights the advantages of in situ ligand substitution for MOF modification, by which uniform distribution and high content of the incoming ligand are accessible in the resulting MOFs. More importantly, it provides a promising approach to convert unstable MOFs, which mainly constitute the vast MOF database but have always been neglected, into robust functional materials.
关键词 ：
in situ ligand substitution in situ ligand substitution metal-organic frameworks metal-organic frameworks photocatalytic CO 2 reduction photocatalytic CO 2 reduction porphyrin ligands porphyrin ligands stability enhancement stability enhancement
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| GB/T 7714 | Kong Xiang-Jing , He Tao , Zhou Jian et al. In Situ Porphyrin Substitution in a Zr(IV)-MOF for Stability Enhancement and Photocatalytic CO2 Reduction. [J]. | Small , 2021 : e2005357 . |
| MLA | Kong Xiang-Jing et al. "In Situ Porphyrin Substitution in a Zr(IV)-MOF for Stability Enhancement and Photocatalytic CO2 Reduction." . | Small (2021) : e2005357 . |
| APA | Kong Xiang-Jing , He Tao , Zhou Jian , Zhao Chen , Li Tong-Chuan , Wu Xue-Qian et al. In Situ Porphyrin Substitution in a Zr(IV)-MOF for Stability Enhancement and Photocatalytic CO2 Reduction. . | Small , 2021 , e2005357 . |
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摘要 ：
Enhancing electrocatalytic water splitting performance by modulating the intrinsic electronic structure is of great importance. Here, porous bimetallic oxide and chalcogenide nanosheets grown on carbon paper denoted as NiCo2X4/CP (X = O, S, and Se) are prepared to demonstrate how the anion components affect the electronic structures and thereby disclose the correlation between their intermediates interaction and catalytic activities. The experimental characterization and theoretical calculation demonstrate that Se and S substitution can promote the ratio of Co3+/Co2+ and thereby modulate the electronic structure accompanied with the upshift of d band centers, which not only enhance the inner conductivity but also regulate the interaction between the catalyst surface and intermediates, especially for the adsorption of absorbed H and hydroperoxy intermediates towards respective hydrogen evolution reaction (HER) and oxygen evolution reaction (OER). As a result, a full alkaline electrolyzer using NiCo2Se4/CP and NiCo2S4/CP as cathode and anode delivers a low voltage of 1.51 V at 10 mAcm(-2), which is comparable even superior to most transition metal-based electrolyzers.
关键词 ：
bimetallic chalcogenide bimetallic chalcogenide electrocatalytic overall water splitting electrocatalytic overall water splitting electronic structure electronic structure high valence Co3+ high valence Co3+ intermediates interaction intermediates interaction
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| GB/T 7714 | Zhou, Jian , Dou, Yibo , He, Tao et al. Revealing the effect of anion-tuning in bimetallic chalcogenides on electrocatalytic overall water splitting [J]. | NANO RESEARCH , 2021 , 14 (12) : 4548-4555 . |
| MLA | Zhou, Jian et al. "Revealing the effect of anion-tuning in bimetallic chalcogenides on electrocatalytic overall water splitting" . | NANO RESEARCH 14 . 12 (2021) : 4548-4555 . |
| APA | Zhou, Jian , Dou, Yibo , He, Tao , Zhou, Awu , Kong, Xiang-Jing , Wu, Xue-Qian et al. Revealing the effect of anion-tuning in bimetallic chalcogenides on electrocatalytic overall water splitting . | NANO RESEARCH , 2021 , 14 (12) , 4548-4555 . |
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摘要 ：
Mineral grain size heterogeneity is one of the fundamental reasons leading to differences in rock mechanical behaviours. Several indices have been proposed to quantify grain size heterogeneity, however, the applicability of the existing indices is limited due to various preconditions. An improved grain size heterogeneity index H-e was proposed in this study. By comparing with the previous index, the improved index was proved to be more applicable for analysing rock mechanical properties. Through a series of grain-based model (GBM), the grain size heterogeneity effect, material heterogeneity effect and mineral content effect were further discussed. For a simple grain size heterogeneity effect, the crack initiation stress, damage stress, peak stress and crack initiation stress ratio of rock decreased linearly as the improved index H-e increased. After accounting for the material heterogeneity effect, the above characteristic stresses and elastic modulus decreased. A significant material heterogeneity effect and mineral content effect will impact the linear correlation between the rock macromechanical parameters and the H-e index. When the axial stress was low, the grain size heterogeneity had little effect on the number of microcracks, but this heterogeneity became the main factor affecting the evolution of microcracks as the axial stress increased. The number of intragrain tensile cracks increases and the number of intergrain shear cracks decreases with increasing H-e, when the axial stress reached the rock peak strength. Besides, the combined effects of material heterogeneity and mineral content may control the type and number of microcracks, further weakening the effect of grain size heterogeneity.
关键词 ：
Particle flow code Particle flow code Alxa granite Alxa granite Heterogeneity index Heterogeneity index Grain-based modelling Grain-based modelling Grain size heterogeneity Grain size heterogeneity
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| GB/T 7714 | Han, Zhenhua , Zhang, Luqing , Azzam, Rafig et al. A statistical index indicating the degree and mechanical effects of grain size heterogeneity in rocks [J]. | ENGINEERING GEOLOGY , 2021 , 293 . |
| MLA | Han, Zhenhua et al. "A statistical index indicating the degree and mechanical effects of grain size heterogeneity in rocks" . | ENGINEERING GEOLOGY 293 (2021) . |
| APA | Han, Zhenhua , Zhang, Luqing , Azzam, Rafig , Zhou, Jian , Wang, Song . A statistical index indicating the degree and mechanical effects of grain size heterogeneity in rocks . | ENGINEERING GEOLOGY , 2021 , 293 . |
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摘要 ：
The grain-based model (GBM) in two-dimensional Particle Flow Code (PFC2D) is widely employed to investigate the mechanical response characteristics of crystalline rocks under external load considering the realistic petrographic texture. However, due to the poor self-locking effect of the Parallel-Bond (PB) inside the minerals and unreasonable parametric assignment for the Smooth-Joint (SJ) at the mineral boundaries, the original GBM cannot reproduce the exact microcracking process of brittle rocks. To solve the problem, the novel grain-based model (nGBM) composed of the Flat-Joint (FJ) and the SJ was proposed in our previous research, which not only enhances the rotational resistance of particles, but also improves the simulation of the mineral boundaries. In this study, the nGBM was carefully established and calibrated based on the properties of Alxa porphyritic granite. A series of simulation tests of uniaxial compression, triaxial compression and direct tension under different mineral boundary parametric conditions were carried out to observe the deformation, microcracking and failure behaviors of the nGBM. Quantitative analyses of the mineral boundary properties and the mechanical behaviors of the numerical specimen revealed the extremely complicated relationships between them, which can help explain the micromechanical damage process of crystalline rocks and provide valuable reference for the model calibration. © 2020 Elsevier Ltd
关键词 ：
Crystalline rocks Crystalline rocks Microcracking Microcracking Minerals Minerals Textures Textures
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| GB/T 7714 | Wang, Song , Zhou, Jian , Zhang, Luqing et al. Parameter studies on the mineral boundary strength influencing the fracturing of the crystalline rock based on a novel Grain-Based Model [J]. | Engineering Fracture Mechanics , 2021 , 241 . |
| MLA | Wang, Song et al. "Parameter studies on the mineral boundary strength influencing the fracturing of the crystalline rock based on a novel Grain-Based Model" . | Engineering Fracture Mechanics 241 (2021) . |
| APA | Wang, Song , Zhou, Jian , Zhang, Luqing , Han, Zhenhua , Zhang, Fenxiang . Parameter studies on the mineral boundary strength influencing the fracturing of the crystalline rock based on a novel Grain-Based Model . | Engineering Fracture Mechanics , 2021 , 241 . |
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摘要 ：
The grain-based model (GBM) in two-dimensional Particle Flow Code (PFC2D) is widely used to simulate the deformation and brittle failure of crystalline rocks. However, the original GBM consisting of the parallel-bond (PB) and the smooth-joint (SJ) produces unrealistic micro-cracking processes in which excessive microcracks are distributed along the interfaces of mineral grains under uniaxial loading. To solve the problem, this research presents a discussion of the mechanical behavior of six GBMs composed of different contact models including PB, SJ, and flat-joint (FJ). After the uniaxial compressive and direct tensile tests of numerical granites, it is found that the different contact types in GBMs have a limited influence on the tensile strength (TS), elastic modulus (E), and Poisson's ratio (nu) but have a great impact on the uniaxial compressive strength (UCS) and microcrack pattern. The UCS calculated by the PB/FJ GBM is higher than the actual value. Microcrack distributions simulated by the FJ/SJ and FJ/PB GBMs show that numerous mineral grains are cut across under uniaxial loading instead of their interfaces. While the FJ/SJ and FJ/PB GBMs may well reproduce the brittle failure process of crystalline rocks, it remains to be seen whether they will be applicable to other rock mechanics issues, including triaxial compression, thermal cracking, and hydraulic fracturing.
关键词 ：
Crystalline rock Crystalline rock Grain-based model Grain-based model Micro-cracking evolution Micro-cracking evolution Numerical modeling Numerical modeling Particle Flow Code Particle Flow Code
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| GB/T 7714 | Wang, Song , Zhou, Jian , Zhang, Luqing et al. A modeling study of the micro-cracking behavior of brittle crystalline rocks under uniaxial loading considering different scenarios of grain-based models [J]. | ARABIAN JOURNAL OF GEOSCIENCES , 2021 , 14 (4) . |
| MLA | Wang, Song et al. "A modeling study of the micro-cracking behavior of brittle crystalline rocks under uniaxial loading considering different scenarios of grain-based models" . | ARABIAN JOURNAL OF GEOSCIENCES 14 . 4 (2021) . |
| APA | Wang, Song , Zhou, Jian , Zhang, Luqing , Han, Zhenhua , Zhang, Fenxiang . A modeling study of the micro-cracking behavior of brittle crystalline rocks under uniaxial loading considering different scenarios of grain-based models . | ARABIAN JOURNAL OF GEOSCIENCES , 2021 , 14 (4) . |
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摘要 ：
This paper studies the dynamic behaviors of a magnetically coupled oscillator with two degrees-of-freedom. For the certain parameter combinations, the target component (TC), which is excited by a base movement, enters the saturated steady-state responses. Another component, which is called as the spatially constrained system (SCS), is considered as an energy absorber pumping out of the energy from the TC under 1:3 internal resonance. The governing equations of motion are derived using a magnetic dipole model and then are solved with the method of multiple scales. The energy distributions between the TC and SCS can vary with the base movement amplitude and excitation frequency. The saturation behavior is found and used for constraining the moving amplitude of an excited system. The bifurcation diagrams reveal the complex and interesting responses when the excitation frequency and amplitude change. The results include the comparisons among the analytical predictions, numerical simulations, and experimental tests. For the purpose of suppressing the primary resonance, the present system effectively transf er the energy from the excited component. The jumping and saturation phenomena are found in the experiments and the changes in the spectrum of two steady-state responses are also observed. (C) 2020 Elsevier Ltd. All rights reserved.
关键词 ：
Internal resonance Internal resonance Magnetic coupled oscillator Magnetic coupled oscillator Method of multiple scales Method of multiple scales Resonance suppression Resonance suppression Spatially constrained system Spatially constrained system
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| GB/T 7714 | Zhou, J. , Zhang, W. , Wang, X. S. et al. Primary resonance suppression of a base excited oscillator using a spatially constrained system: Theory and experiment [J]. | JOURNAL OF SOUND AND VIBRATION , 2021 , 496 . |
| MLA | Zhou, J. et al. "Primary resonance suppression of a base excited oscillator using a spatially constrained system: Theory and experiment" . | JOURNAL OF SOUND AND VIBRATION 496 (2021) . |
| APA | Zhou, J. , Zhang, W. , Wang, X. S. , Mann, B. P. , Dowell, E. H. . Primary resonance suppression of a base excited oscillator using a spatially constrained system: Theory and experiment . | JOURNAL OF SOUND AND VIBRATION , 2021 , 496 . |
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