The high-entropy alloy composite coatings AlCu_(2)Ti(NiCr)_(2)-(WC)_(x)(x denotes powder feeding speeds,including 0,25,50,and 75 r/min)were prepared by plasma cladding using a hybrid mode of AlCu_(2)(NiCr)_(2)Ti cable...The high-entropy alloy composite coatings AlCu_(2)Ti(NiCr)_(2)-(WC)_(x)(x denotes powder feeding speeds,including 0,25,50,and 75 r/min)were prepared by plasma cladding using a hybrid mode of AlCu_(2)(NiCr)_(2)Ti cable-type welding wire(CWW)and tungsten carbide(WC)powder.The effect of WC powder feeding speed on the microstructure,hardness,and wear properties of the prepared coatings was investigated.The results show that the coatings consist of body-centered cubic main phases and face-centered cubic secondary phases,with carbide reinforcement phases formed due to the addition of WC.The hardness and wear resistance of the coatings are significantly improved compared to the TC11 substrate.When WC powder feeding speed is set at 50 r/min,the coating exhibits optimal wear resistance,with a minimum volume wear rate of 8.5869×10^(-6)mm^(3)·N^(-1)·m^(-1),greatly improving the wear properties of TC11 surface.The coincident CWW-powder plasma cladding provides a viable method for the preparation of highentropy alloy composite coatings with enhanced wear resistance.展开更多
网页认知走查法(Cognitive Walkthrough for the Web,CWW)是专门用于网页可用性评估的半自动评估工具,文章在国外相关研究的基础上结合对该工具的实际应用,对网页认知走查法的理论模型基础、研究进程、方法的思想来源、实现基础及运行...网页认知走查法(Cognitive Walkthrough for the Web,CWW)是专门用于网页可用性评估的半自动评估工具,文章在国外相关研究的基础上结合对该工具的实际应用,对网页认知走查法的理论模型基础、研究进程、方法的思想来源、实现基础及运行过程、优缺点评价等方面进行了详细评述,并对该方法的未来发展方向进行了展望。展开更多
Cable welding wire(CWW)CO2gas shielded welding is an innovative process arc welding with high efficiency,high quality and low consumption,in which cable wire is used as consumable electrode.CWW CO2gas shielded weldi...Cable welding wire(CWW)CO2gas shielded welding is an innovative process arc welding with high efficiency,high quality and low consumption,in which cable wire is used as consumable electrode.CWW CO2gas shielded welding and submerged arc welding(SAW)are used for contrast studies on processing property of high strength steel A36used in ship structure.The results show that the shapes of weld seam,using CWW CO2gas shielded welding and SAW,are good and no weld defect such as air hole,flaw,slag inclusion,incomplete fusion,lack of penetration and so on are found in the weld seam.Because the rotating of arc during CWW CO2gas shielded welding process has a strong stirring effect on molten pool,the grain in the heat affected zone(HAZ)of the joints,using CWW CO2 gas shielded welding,is small.Tensile failure positions of joints by CWW CO2gas shielded welding and SAW are all in the base metal,but tensile strength of CWW CO2gas shielded welding joint is higher than that of SAW joint by an average of 2.3%.The average impact energy of HAZ,using CWW CO2gas shielded welding and SAW,is almost equal,but the average impact energy of the weld seam using CWW CO2gas shielded welding is increased by 6%,and the average impact energy of the fusion line is increased by 7%.The 180°bending tests for the joints of CWW CO2 gas shielded welding and SAW are all qualified,and the joints hardness is all less than HV 355,but hardness of CWW CO2gas shielded welding wire welding joint near the fusion line is obviously lower.It can be concluded that the properties of CWW CO2gas shielded welding are better than those of the SAW joint,and CWW CO2gas shielded welding is suitable for welding high strength steel A36used in ship structure.展开更多
Currently, only a few states in the U.S. (e.g. Colorado and Ohio) require mandatory baseline groundwater sampling from nearby groundwater wells prior to drilling a new oil or gas well. Colorado is the first state to r...Currently, only a few states in the U.S. (e.g. Colorado and Ohio) require mandatory baseline groundwater sampling from nearby groundwater wells prior to drilling a new oil or gas well. Colorado is the first state to regulate groundwater testing before and after drilling, requiring one pre-drilling sample and two additional post-drilling samples within 6 - 12 months and 5 - 6 years of drilling, respectively. However, the monitoring method is limited to ex-situ sampling, which offers only a snapshot in time. To overcome the limitations and increase monitoring effectiveness, a new groundwater monitoring system, Colorado Water Watch (CWW), was introduced as a decision-making tool to support the state’s regulatory agency and also to provide real-time groundwater quality data to both industry and the public. The CWW uses simple in-situ water quality sensors based on surrogate sensing technology that employs an event detection system to screen the incoming data in near real-time. This objective of this study was to improve the understanding of groundwater quality in Wattenberg field and assess event detection methods. The data obtained from 5 sites (the earliest monitoring sites in the CWW network) for 3 years of the regional monitoring network in Wattenberg field is used to illustrate the background information about groundwater quality and its changing trend, and make comparisons between two outlier detection methods, CANARY and simple moving median.展开更多
基金National Natural Science Foundation of China(51764038)Gansu Science and Technology Planning Project(2022JR5RA314,22YF7WA151,22YF7GA138,23CXGA0151)+1 种基金Gansu Provincial Department of Education:Industrial Support Plan Project(2022CYZC-31)Gansu Provincial Association of Science and Technology Innovation Driving Force Project(GXH20230817-10)。
文摘The high-entropy alloy composite coatings AlCu_(2)Ti(NiCr)_(2)-(WC)_(x)(x denotes powder feeding speeds,including 0,25,50,and 75 r/min)were prepared by plasma cladding using a hybrid mode of AlCu_(2)(NiCr)_(2)Ti cable-type welding wire(CWW)and tungsten carbide(WC)powder.The effect of WC powder feeding speed on the microstructure,hardness,and wear properties of the prepared coatings was investigated.The results show that the coatings consist of body-centered cubic main phases and face-centered cubic secondary phases,with carbide reinforcement phases formed due to the addition of WC.The hardness and wear resistance of the coatings are significantly improved compared to the TC11 substrate.When WC powder feeding speed is set at 50 r/min,the coating exhibits optimal wear resistance,with a minimum volume wear rate of 8.5869×10^(-6)mm^(3)·N^(-1)·m^(-1),greatly improving the wear properties of TC11 surface.The coincident CWW-powder plasma cladding provides a viable method for the preparation of highentropy alloy composite coatings with enhanced wear resistance.
文摘网页认知走查法(Cognitive Walkthrough for the Web,CWW)是专门用于网页可用性评估的半自动评估工具,文章在国外相关研究的基础上结合对该工具的实际应用,对网页认知走查法的理论模型基础、研究进程、方法的思想来源、实现基础及运行过程、优缺点评价等方面进行了详细评述,并对该方法的未来发展方向进行了展望。
基金Sponsored by National Natural Science Foundation of China(51275224,51005106)Prospective Joint Research Project ofJiangsu Province of China(BY2012184)
文摘Cable welding wire(CWW)CO2gas shielded welding is an innovative process arc welding with high efficiency,high quality and low consumption,in which cable wire is used as consumable electrode.CWW CO2gas shielded welding and submerged arc welding(SAW)are used for contrast studies on processing property of high strength steel A36used in ship structure.The results show that the shapes of weld seam,using CWW CO2gas shielded welding and SAW,are good and no weld defect such as air hole,flaw,slag inclusion,incomplete fusion,lack of penetration and so on are found in the weld seam.Because the rotating of arc during CWW CO2gas shielded welding process has a strong stirring effect on molten pool,the grain in the heat affected zone(HAZ)of the joints,using CWW CO2 gas shielded welding,is small.Tensile failure positions of joints by CWW CO2gas shielded welding and SAW are all in the base metal,but tensile strength of CWW CO2gas shielded welding joint is higher than that of SAW joint by an average of 2.3%.The average impact energy of HAZ,using CWW CO2gas shielded welding and SAW,is almost equal,but the average impact energy of the weld seam using CWW CO2gas shielded welding is increased by 6%,and the average impact energy of the fusion line is increased by 7%.The 180°bending tests for the joints of CWW CO2 gas shielded welding and SAW are all qualified,and the joints hardness is all less than HV 355,but hardness of CWW CO2gas shielded welding wire welding joint near the fusion line is obviously lower.It can be concluded that the properties of CWW CO2gas shielded welding are better than those of the SAW joint,and CWW CO2gas shielded welding is suitable for welding high strength steel A36used in ship structure.
文摘Currently, only a few states in the U.S. (e.g. Colorado and Ohio) require mandatory baseline groundwater sampling from nearby groundwater wells prior to drilling a new oil or gas well. Colorado is the first state to regulate groundwater testing before and after drilling, requiring one pre-drilling sample and two additional post-drilling samples within 6 - 12 months and 5 - 6 years of drilling, respectively. However, the monitoring method is limited to ex-situ sampling, which offers only a snapshot in time. To overcome the limitations and increase monitoring effectiveness, a new groundwater monitoring system, Colorado Water Watch (CWW), was introduced as a decision-making tool to support the state’s regulatory agency and also to provide real-time groundwater quality data to both industry and the public. The CWW uses simple in-situ water quality sensors based on surrogate sensing technology that employs an event detection system to screen the incoming data in near real-time. This objective of this study was to improve the understanding of groundwater quality in Wattenberg field and assess event detection methods. The data obtained from 5 sites (the earliest monitoring sites in the CWW network) for 3 years of the regional monitoring network in Wattenberg field is used to illustrate the background information about groundwater quality and its changing trend, and make comparisons between two outlier detection methods, CANARY and simple moving median.