Water outlets for washing hands and medical equipment are essential for preventing hospital infection. The present study clarified the effects of water flow volume on the identification and quantitative evaluation of ...Water outlets for washing hands and medical equipment are essential for preventing hospital infection. The present study clarified the effects of water flow volume on the identification and quantitative evaluation of bacteria found around spouts in the 17 hand-washing stations. Pseu-domonas aeruginosa was detected from 4 sta-tions before adjustment and 2 after adjustment. Although no significant difference was identified in the detection rate of P. aeruginosa (p = 0.368), when combining P. aeruginosa and glucose non-fermentative Gram-negative bacilli (NFB), the number of stations with P. aeruginosa and/or NFB decreased significantly from 15 before adjustment to 9 after adjustment (p = 0.023). Before adjust-ment, quantity of bacteria was “2+” for 3 stations and “1+” for 7 stations, but was “1+” for 3 stations and “2+” for 0 stations after adjustment. These results show that quantity of bacteria could be reduced from spouts by adjusting flow volume. These results were also supported by experiments for cleanliness using Adenosine 5’-triphosphate bioluminescence me- thod.展开更多
The highly efficient KQ series Kangquan brand water mineralization and purification devices for faucets, produced by the Tianjin Kangquan Purification Equipment Factory, enables people to obtain pure mineralized water...The highly efficient KQ series Kangquan brand water mineralization and purification devices for faucets, produced by the Tianjin Kangquan Purification Equipment Factory, enables people to obtain pure mineralized water from their taps. The products combine the strong points展开更多
Microbial contamination in building plumbing systems poses significant risks to public health at the point of use.Stagnation and warm temperatures are well-known drivers of microbial regrowth,but the effects of common...Microbial contamination in building plumbing systems poses significant risks to public health at the point of use.Stagnation and warm temperatures are well-known drivers of microbial regrowth,but the effects of common short-term stagnation in touchless sensor faucets—widely used for hygiene and comfort—remain poorly understood.Here we show that microbial water quality in touchless sensor faucets changes during short-term stagnation(0.25-10 h)at varying temperatures(10,30,and 40℃).We identify two pivotal time points—2 and 4 h—where microbial diversity decreases and Legionella pneumophila concentrations increase significantly,driven by accelerated chlorine decay and biofilm contributions.Heating to 30℃ maximizes microbial biomass(measured as ATP)but minimizes L.pneumophila proliferation,whereas 40℃ reduces biomass while promoting L.pneumophila growth.These findings reveal a temperature-dependent microbial water quality guarantee period of 2-4 h,beyond which flushing is necessary to mitigate health risks.Optimizing faucet temperatures between 30 and 40℃ could balance microbial safety,user comfort,and energy efficiency,offering practical guidance for managing water quality in modern plumbing systems.展开更多
In this study,a one-dimensional two-phase flow four-equation model was developed to simulate the water faucet problem.The performance of six different Krylov subspace methods,namely the generalized minimal residual(GM...In this study,a one-dimensional two-phase flow four-equation model was developed to simulate the water faucet problem.The performance of six different Krylov subspace methods,namely the generalized minimal residual(GMRES),transpose-free quasi-minimal residual,quasi-minimal residual,conjugate gradient squared,biconjugate gradient stabilized,and biconjugate gradient,was evaluated with and without the application of an incomplete LU(ILU)factorization preconditioner for solving the water faucet problem.The simulation results indicate that using the ILU preconditioner with the Krylov subspace methods produces better convergence performance than that without the ILU preconditioner.Only the GMRES demonstrated an acceptable convergence performance under the Krylov subspace methods without the preconditioner.The velocity and pressure distribution in the water faucet problem could be determined using the Krylov subspace methods with an ILU preconditioner,while GMRES could determine it without the need for a preconditioner.However,there are significant advantages of using an ILU preconditioner with the GMRES in terms of efficiency.The different Krylov subspace methods showed similar performance in terms of computational efficiency under the application of the ILU preconditioner.展开更多
In this study,the reason for erosion-corrosion of drinking or mains water in the faucet was investigated by computational fluid dynamics.Pipes used in homes,the service sector,and industry are responsible for transpor...In this study,the reason for erosion-corrosion of drinking or mains water in the faucet was investigated by computational fluid dynamics.Pipes used in homes,the service sector,and industry are responsible for transporting different types of fluids from one place to another.Considering the faucet design,the SolidWorks program was used for 3D studies.In-faucet flow analyses were performed using Ansys Fluent,a computational fluid dynamics program based on the finite volume method.In the analyses,lime particles were chosen.At the end of the analysis,the amount of erosion in the faucet was obtained.展开更多
Cao Yu's work is known for its boldness,subversion,and uncompromising nature,earning her recognition as one of China's most influential young artists In front of a faded red brick wall,a woman in a black blaze...Cao Yu's work is known for its boldness,subversion,and uncompromising nature,earning her recognition as one of China's most influential young artists In front of a faded red brick wall,a woman in a black blazer and pants sits on a concrete sink,chest partly exposed,legs spread wide.From between them a broken faucet erupts,ejecting a violent stream of water like a flash of blinding light.The posture blurs the lines between masculine and feminine,and the subject's intense gaze commands attention,daring viewers to confront her and the explicitly subversive intent behind the image.展开更多
文摘Water outlets for washing hands and medical equipment are essential for preventing hospital infection. The present study clarified the effects of water flow volume on the identification and quantitative evaluation of bacteria found around spouts in the 17 hand-washing stations. Pseu-domonas aeruginosa was detected from 4 sta-tions before adjustment and 2 after adjustment. Although no significant difference was identified in the detection rate of P. aeruginosa (p = 0.368), when combining P. aeruginosa and glucose non-fermentative Gram-negative bacilli (NFB), the number of stations with P. aeruginosa and/or NFB decreased significantly from 15 before adjustment to 9 after adjustment (p = 0.023). Before adjust-ment, quantity of bacteria was “2+” for 3 stations and “1+” for 7 stations, but was “1+” for 3 stations and “2+” for 0 stations after adjustment. These results show that quantity of bacteria could be reduced from spouts by adjusting flow volume. These results were also supported by experiments for cleanliness using Adenosine 5’-triphosphate bioluminescence me- thod.
文摘The highly efficient KQ series Kangquan brand water mineralization and purification devices for faucets, produced by the Tianjin Kangquan Purification Equipment Factory, enables people to obtain pure mineralized water from their taps. The products combine the strong points
基金supported by the National Natural Science Foundation of China(52388101,52370105,52022103).
文摘Microbial contamination in building plumbing systems poses significant risks to public health at the point of use.Stagnation and warm temperatures are well-known drivers of microbial regrowth,but the effects of common short-term stagnation in touchless sensor faucets—widely used for hygiene and comfort—remain poorly understood.Here we show that microbial water quality in touchless sensor faucets changes during short-term stagnation(0.25-10 h)at varying temperatures(10,30,and 40℃).We identify two pivotal time points—2 and 4 h—where microbial diversity decreases and Legionella pneumophila concentrations increase significantly,driven by accelerated chlorine decay and biofilm contributions.Heating to 30℃ maximizes microbial biomass(measured as ATP)but minimizes L.pneumophila proliferation,whereas 40℃ reduces biomass while promoting L.pneumophila growth.These findings reveal a temperature-dependent microbial water quality guarantee period of 2-4 h,beyond which flushing is necessary to mitigate health risks.Optimizing faucet temperatures between 30 and 40℃ could balance microbial safety,user comfort,and energy efficiency,offering practical guidance for managing water quality in modern plumbing systems.
文摘In this study,a one-dimensional two-phase flow four-equation model was developed to simulate the water faucet problem.The performance of six different Krylov subspace methods,namely the generalized minimal residual(GMRES),transpose-free quasi-minimal residual,quasi-minimal residual,conjugate gradient squared,biconjugate gradient stabilized,and biconjugate gradient,was evaluated with and without the application of an incomplete LU(ILU)factorization preconditioner for solving the water faucet problem.The simulation results indicate that using the ILU preconditioner with the Krylov subspace methods produces better convergence performance than that without the ILU preconditioner.Only the GMRES demonstrated an acceptable convergence performance under the Krylov subspace methods without the preconditioner.The velocity and pressure distribution in the water faucet problem could be determined using the Krylov subspace methods with an ILU preconditioner,while GMRES could determine it without the need for a preconditioner.However,there are significant advantages of using an ILU preconditioner with the GMRES in terms of efficiency.The different Krylov subspace methods showed similar performance in terms of computational efficiency under the application of the ILU preconditioner.
文摘In this study,the reason for erosion-corrosion of drinking or mains water in the faucet was investigated by computational fluid dynamics.Pipes used in homes,the service sector,and industry are responsible for transporting different types of fluids from one place to another.Considering the faucet design,the SolidWorks program was used for 3D studies.In-faucet flow analyses were performed using Ansys Fluent,a computational fluid dynamics program based on the finite volume method.In the analyses,lime particles were chosen.At the end of the analysis,the amount of erosion in the faucet was obtained.
文摘Cao Yu's work is known for its boldness,subversion,and uncompromising nature,earning her recognition as one of China's most influential young artists In front of a faded red brick wall,a woman in a black blazer and pants sits on a concrete sink,chest partly exposed,legs spread wide.From between them a broken faucet erupts,ejecting a violent stream of water like a flash of blinding light.The posture blurs the lines between masculine and feminine,and the subject's intense gaze commands attention,daring viewers to confront her and the explicitly subversive intent behind the image.
