Underground geotechnical engineering encounters persistent challenges in ensuring the stability and safety of surrounding rock structures, particularly within rocky tunnels. Rock reinforcement techniques, including th...Underground geotechnical engineering encounters persistent challenges in ensuring the stability and safety of surrounding rock structures, particularly within rocky tunnels. Rock reinforcement techniques, including the use of steel mesh, are critical to achieving this goal. However, there exists a knowledge gap regarding the comprehensive understanding of the mechanical behavior and failure mechanisms exhibited by steel mesh under diverse loading conditions. This study thoroughly explored the steel mesh's performance throughout the entire loading-failure process, innovating with detailed analysis and modeling techniques. By integrating advanced numerical modeling with laboratory experiments, the study examines the influence of varying reinforcement levels and geometric parameters on the steel mesh strength and deformation characteristics. Sensitivity analysis, employing gray correlation theory, identifies the key factors affecting the mesh performance, while a BP (Backpropagation) neural network model predicts maximum vertical deformation with high accuracy. The findings underscore the critical role of steel diameter and mesh spacing in optimizing peak load capacity, displacement, and energy absorption, offering practical guidelines for design improvements. The use of a Bayesian Regularization (BR) algorithm further enhances the predictive accuracy compared to traditional methods. This research provides new insights into optimizing steel mesh design for underground applications, offering an innovative approach to enhancing structural safety in geotechnical projects.展开更多
Steel mesh is used as a passive skin confinement medium to supplement the active support provided by rock bolts for roof and rib control in underground coal mines. Thin spray-on liners(TSL) are believed to have the po...Steel mesh is used as a passive skin confinement medium to supplement the active support provided by rock bolts for roof and rib control in underground coal mines. Thin spray-on liners(TSL) are believed to have the potential to take the place of steel mesh as the skin confinement medium in underground mines.To confirm this belief, large scale laboratory experiments were conducted to compare the behaviour of welded steel mesh and a TSL, when used in conjunction with rock bolts, in reinforcing strata with weak bedding planes and strata prone to guttering, two common rock conditions which exist in coal mines. It was found that while the peak load taken by the simulated rock mass with weak bedding planes acting as the control sample(no skin confinement) was 2494 kN, the corresponding value of the sample with 5 mm thick TSL reinforcement reached 2856 kN. The peak load of the steel mesh reinforced sample was only2321 kN, but this was attributed to the fact that one of the rock bolts broke during the test. The TSL reinforced sample had a similar post-yield behaviour as the steel mesh reinforced one. The results of the large scale guttering test indicated that a TSL is better than steel mesh in restricting rock movement and thus inhibiting the formation of gutters in the roof.展开更多
The oxygen evolution reaction(OER)represents one of the major bottlenecks for broad-based applications of many clean energy storage/conversion technologies.The key to solving this problem lies in developing high-perfo...The oxygen evolution reaction(OER)represents one of the major bottlenecks for broad-based applications of many clean energy storage/conversion technologies.The key to solving this problem lies in developing high-performing,cost effective and stable catalysts for the OER.Herein,we demonstrate that ubiquitous stainless steel mesh(SSM)materials activated by a facile cathodization treatment can be employed as a high performing OER catalyst,as showcased by the impressively low overpotentials of 275 and 319 mV to reach the benchmark current densities of 10 and 100 mA cm^−2(1.0 M KOH),respectively.Cathodized SSM also exhibits excellent performance in a two-electrode water electrolyzer,which requires a low cell voltage of 1.58 at 10 mA cm^−2 and outperforms many of water electrolyzers using earth-abundant OER catalysts.Moreover,cathodized SSM with minor performance degradation after the stability test can also be readily healed by subjecting it to an additional cathodization treatment.It is disclosed that the superior performance of cathodized SSMs stems from the surface enrichment of OER active Ni(oxy)hydroxide,facile gas-bubble removal and transportation over the unique mesh-structured surfaces,while the abundant reservoir of nickel in the bulk allows healing of the catalyst by a facile cathodization.展开更多
Because of the increasing amount of oily wastewater produced each day,it is important to develop superhydrophilic/underwater superoleophobic oil/water separation membranes with ultrahigh flux and high separation effic...Because of the increasing amount of oily wastewater produced each day,it is important to develop superhydrophilic/underwater superoleophobic oil/water separation membranes with ultrahigh flux and high separation efficiency.In this paper,a superhydrophilic/underwater superoleophobic N-isopropylacrylamide-coated stainless steel mesh was prepared through a simple and convenient graft polymerization approach.The obtained mesh was able to separate oil/water mixtures only by gravity.In addition,the mesh showed high-efficiency separation ability(99.2%)and ultrahigh flux(235239 L·m^(−2)·h^(−1)).Importantly,due to the complex cross-linked bilayer structure,the prepared mesh exhibited good recycling performance and chemical stability in highly saline,alkaline and acidic environments.展开更多
The development of an electrocatalyst based on abundant elements for the oxygen evolution reaction （OER） is important for water splitting associated with renewable energy sources. In this study, we develop an interc...The development of an electrocatalyst based on abundant elements for the oxygen evolution reaction （OER） is important for water splitting associated with renewable energy sources. In this study, we develop an interconnected Ni（Fe）OxHy nanosheet array on a stainless steel mesh （SSNNi） as an integrated OER electrode, without using any polymer binder. Benefiting from the well- defined three-dimensional （3D） architecture with highly exposed surface area, intimate contact between the active species and conductive substrate improved electron and mass transport capacity, facilitated electrolyte penetration, and improved mechanical stability. The SSNNi electrode also has excellent OER performance, including low overpotential, a small Tafel slope, and long-term durability in the alkaline electrolyte, making it one of the most promising OER electrodes developed.展开更多
A series of zinc oxide(ZnO)nanorods arrays with different morphologies are synthesized on stainless steel mesh via a facile electrodeposition method.The influences of electrodeposition parameters on the diameter,lengt...A series of zinc oxide(ZnO)nanorods arrays with different morphologies are synthesized on stainless steel mesh via a facile electrodeposition method.The influences of electrodeposition parameters on the diameter,length,density and morphology of obtained ZnO nanorods are investigated systematically.The results indicate that the electrodeposition potential is the key factor for the morphology of the obtained ZnO nanorods,which further showed the effect on the photocatalytic property of the obtained samples.Meanwhile,the prepared ZnO nanorods array exhibits an excellent photocatalytic activity for methylene blue(MB)in ultraviolet light.The degradation efficiency for MB solution reaches 95.1%under the irradiation of ultraviolet light for 120 min.In addition,the photocatalytic property of the prepared ZnO nanorods can be extended to the visible light region after the modified with graphene oxide(GO).The obtained GO/ZnO composite also shows remarkable photocatalytic activity and photostability.The photodegradation efficiency for MB is 83.6%,and the catalytic performance retains 97.3% of its initial photocatalytic activity after five cycles.展开更多
Steel bar in concrete structures under harsh environmental conditions, such as chlorine corrosion, seriously affects its service life. Bidirectional electromigration rehabilitation （BIEM） is a new method of repair t...Steel bar in concrete structures under harsh environmental conditions, such as chlorine corrosion, seriously affects its service life. Bidirectional electromigration rehabilitation （BIEM） is a new method of repair technology for reinforced concrete structures in such chloride corrosion environments. By applying the BIEM, chloride ions can be removed from the concrete and the migrating corrosion inhibit can be moved to the steel surface. In conventional engineering, the concrete structure is often configured with a multi-layer steel mesh. However, the effect of the BIEM in such structures has not yet been investigated. In this paper, the relevant simulation test is carried out to study the migration law of chloride ions and the migrating corrosion inhibitor in a concrete specimen with complex steel mesh under different energizing modes. The results show that the efficiency of the BIEM increases 50% in both the monolayer steel mesh and the double-layer steel mesh. By using the single-sided BIEM, 87% of the chloride ions are removed from the steel surface. The different step modes can affect the chloride ion removal. The chloride ions within the range of the reinforcement protective cover are easier to be removed than those in the concrete between the two layers of steel mesh. However, the amount of migrating corrosion inhibitor is larger in the latter circumstances.展开更多
基金funded by the National Natural Science Foundation of China(Grant No.52178396).
文摘Underground geotechnical engineering encounters persistent challenges in ensuring the stability and safety of surrounding rock structures, particularly within rocky tunnels. Rock reinforcement techniques, including the use of steel mesh, are critical to achieving this goal. However, there exists a knowledge gap regarding the comprehensive understanding of the mechanical behavior and failure mechanisms exhibited by steel mesh under diverse loading conditions. This study thoroughly explored the steel mesh's performance throughout the entire loading-failure process, innovating with detailed analysis and modeling techniques. By integrating advanced numerical modeling with laboratory experiments, the study examines the influence of varying reinforcement levels and geometric parameters on the steel mesh strength and deformation characteristics. Sensitivity analysis, employing gray correlation theory, identifies the key factors affecting the mesh performance, while a BP (Backpropagation) neural network model predicts maximum vertical deformation with high accuracy. The findings underscore the critical role of steel diameter and mesh spacing in optimizing peak load capacity, displacement, and energy absorption, offering practical guidelines for design improvements. The use of a Bayesian Regularization (BR) algorithm further enhances the predictive accuracy compared to traditional methods. This research provides new insights into optimizing steel mesh design for underground applications, offering an innovative approach to enhancing structural safety in geotechnical projects.
文摘Steel mesh is used as a passive skin confinement medium to supplement the active support provided by rock bolts for roof and rib control in underground coal mines. Thin spray-on liners(TSL) are believed to have the potential to take the place of steel mesh as the skin confinement medium in underground mines.To confirm this belief, large scale laboratory experiments were conducted to compare the behaviour of welded steel mesh and a TSL, when used in conjunction with rock bolts, in reinforcing strata with weak bedding planes and strata prone to guttering, two common rock conditions which exist in coal mines. It was found that while the peak load taken by the simulated rock mass with weak bedding planes acting as the control sample(no skin confinement) was 2494 kN, the corresponding value of the sample with 5 mm thick TSL reinforcement reached 2856 kN. The peak load of the steel mesh reinforced sample was only2321 kN, but this was attributed to the fact that one of the rock bolts broke during the test. The TSL reinforced sample had a similar post-yield behaviour as the steel mesh reinforced one. The results of the large scale guttering test indicated that a TSL is better than steel mesh in restricting rock movement and thus inhibiting the formation of gutters in the roof.
基金funding from the European Research Council(ERC)under the European Union’s Horizon 2020 research and innovation program(grant agreement No.681719)L.-L.S.acknowledges the funding from the China Scholarship Council(No.201506210077)。
文摘The oxygen evolution reaction(OER)represents one of the major bottlenecks for broad-based applications of many clean energy storage/conversion technologies.The key to solving this problem lies in developing high-performing,cost effective and stable catalysts for the OER.Herein,we demonstrate that ubiquitous stainless steel mesh(SSM)materials activated by a facile cathodization treatment can be employed as a high performing OER catalyst,as showcased by the impressively low overpotentials of 275 and 319 mV to reach the benchmark current densities of 10 and 100 mA cm^−2(1.0 M KOH),respectively.Cathodized SSM also exhibits excellent performance in a two-electrode water electrolyzer,which requires a low cell voltage of 1.58 at 10 mA cm^−2 and outperforms many of water electrolyzers using earth-abundant OER catalysts.Moreover,cathodized SSM with minor performance degradation after the stability test can also be readily healed by subjecting it to an additional cathodization treatment.It is disclosed that the superior performance of cathodized SSMs stems from the surface enrichment of OER active Ni(oxy)hydroxide,facile gas-bubble removal and transportation over the unique mesh-structured surfaces,while the abundant reservoir of nickel in the bulk allows healing of the catalyst by a facile cathodization.
基金the National Natural Science Foundation of China，the China Postdoctoral Science Special Foundation，UTC Exploration Project，the Harbin City Science and Technology Projects
基金supported by the National Natural Science Foundation of China(Grant No.51473070).
文摘Because of the increasing amount of oily wastewater produced each day,it is important to develop superhydrophilic/underwater superoleophobic oil/water separation membranes with ultrahigh flux and high separation efficiency.In this paper,a superhydrophilic/underwater superoleophobic N-isopropylacrylamide-coated stainless steel mesh was prepared through a simple and convenient graft polymerization approach.The obtained mesh was able to separate oil/water mixtures only by gravity.In addition,the mesh showed high-efficiency separation ability(99.2%)and ultrahigh flux(235239 L·m^(−2)·h^(−1)).Importantly,due to the complex cross-linked bilayer structure,the prepared mesh exhibited good recycling performance and chemical stability in highly saline,alkaline and acidic environments.
基金This work is financially supported by the National Natural Science Foundation of China （Nos. 51472209, U1401241, 51522101, 51471075, 5163100, and 51401084）, and Specialized Research Fund for the Doctoral Program of Higher Education of China （No. 20110061120040）.
文摘The development of an electrocatalyst based on abundant elements for the oxygen evolution reaction （OER） is important for water splitting associated with renewable energy sources. In this study, we develop an interconnected Ni（Fe）OxHy nanosheet array on a stainless steel mesh （SSNNi） as an integrated OER electrode, without using any polymer binder. Benefiting from the well- defined three-dimensional （3D） architecture with highly exposed surface area, intimate contact between the active species and conductive substrate improved electron and mass transport capacity, facilitated electrolyte penetration, and improved mechanical stability. The SSNNi electrode also has excellent OER performance, including low overpotential, a small Tafel slope, and long-term durability in the alkaline electrolyte, making it one of the most promising OER electrodes developed.
基金supported by the National Natural Science Foundation of China(Nos.51774217,51604202 and 51604201)the Shanghai Sailing Program(No.19YF1415800)the Key Laboratory for Ferrous Metallurgy and Resources Utilization of Ministry of Education,China(No.FMRU-lab-20-2).
文摘A series of zinc oxide(ZnO)nanorods arrays with different morphologies are synthesized on stainless steel mesh via a facile electrodeposition method.The influences of electrodeposition parameters on the diameter,length,density and morphology of obtained ZnO nanorods are investigated systematically.The results indicate that the electrodeposition potential is the key factor for the morphology of the obtained ZnO nanorods,which further showed the effect on the photocatalytic property of the obtained samples.Meanwhile,the prepared ZnO nanorods array exhibits an excellent photocatalytic activity for methylene blue(MB)in ultraviolet light.The degradation efficiency for MB solution reaches 95.1%under the irradiation of ultraviolet light for 120 min.In addition,the photocatalytic property of the prepared ZnO nanorods can be extended to the visible light region after the modified with graphene oxide(GO).The obtained GO/ZnO composite also shows remarkable photocatalytic activity and photostability.The photodegradation efficiency for MB is 83.6%,and the catalytic performance retains 97.3% of its initial photocatalytic activity after five cycles.
基金financially supported by the National Natural Science Foundation of China(Grant No.51541904)the Natural Science Foundation of Zhejiang Province(Grant No.LY16E090007)the Natural Science Foundation of Ningbo(Grant No.2016A610219)
文摘Steel bar in concrete structures under harsh environmental conditions, such as chlorine corrosion, seriously affects its service life. Bidirectional electromigration rehabilitation （BIEM） is a new method of repair technology for reinforced concrete structures in such chloride corrosion environments. By applying the BIEM, chloride ions can be removed from the concrete and the migrating corrosion inhibit can be moved to the steel surface. In conventional engineering, the concrete structure is often configured with a multi-layer steel mesh. However, the effect of the BIEM in such structures has not yet been investigated. In this paper, the relevant simulation test is carried out to study the migration law of chloride ions and the migrating corrosion inhibitor in a concrete specimen with complex steel mesh under different energizing modes. The results show that the efficiency of the BIEM increases 50% in both the monolayer steel mesh and the double-layer steel mesh. By using the single-sided BIEM, 87% of the chloride ions are removed from the steel surface. The different step modes can affect the chloride ion removal. The chloride ions within the range of the reinforcement protective cover are easier to be removed than those in the concrete between the two layers of steel mesh. However, the amount of migrating corrosion inhibitor is larger in the latter circumstances.
