To improve drying uniformity and anthocyanin content of the raspberry puree dried in a continuous microwave dryer,the effects of process parameters(microwave intensity,air velocity,and drying time)on evaluation indexe...To improve drying uniformity and anthocyanin content of the raspberry puree dried in a continuous microwave dryer,the effects of process parameters(microwave intensity,air velocity,and drying time)on evaluation indexes(average temperature,average moisture content,average retention rate of the total anthocyanin content,temperature contrast value,and moisture dispersion value)were investigated via the response surface method(RSM)and the artificial neural network(ANN)with genetic algorithm(GA).The results showed that the microwave intensity and drying time dominated the changes of evaluation indexes.Overall,the ANN model was superior to the RSM model with better estimation ability,and higher drying uniformity and anthocyanin retention rate were achieved for the ANN-GA model compared with RSM.The optimal parameters were microwave intensity of 5.53 W•g^(-1),air velocity of 1.22 m·s^(-1),and drying time of 5.85 min.This study might provide guidance for process optimization of microwave drying berry fruits.展开更多
AIM: To identify the cut-off value for predicting the ability of elderly patients with dysphagia to swallow pureed diets using a new endoscopy scoring method. METHODS: Endoscopic swallowing evaluation of pureed diets ...AIM: To identify the cut-off value for predicting the ability of elderly patients with dysphagia to swallow pureed diets using a new endoscopy scoring method. METHODS: Endoscopic swallowing evaluation of pureed diets were done in patients ≥ 65 years with dysphagia. The Hyodo-Komagane score for endoscopic swallowing evaluation is expressed as the sum(0-12) of four degrees(0-3) with four parameters:(1) salivary pooling in the vallecula and piriform sinuses;(2) the response of glottal closure reflex induced by touching the epiglottis with the endoscope;(3) the location of the bolus at the time of swallow onset assessed by "white-out" following swallowing of test jelly; and(4) pharyngeal clearance after swallowing of test jelly. We used receiver operating characteristic(ROC) curve analysis to retrospectively analyze the association between the total score and successful oral intake of pureed diets. RESULTS: One hundred and seventy-eight patients were enrolled including 113 men(63%), mean age 83 years(range, 66-98). One hundred and twenty-six patients(71%) were able to eat pureed diets during the observation period(mean ± SD, 19 ± 14 d). In ROC analysis, the cut-off value of the score for eating the pureed diets was 7(sensitivity = 0.98; specificity = 0.91).CONCLUSION: The Hyodo-Komagane endoscopic score is useful to predict the ability to eat pureed diets in elderly patients with dysphagia.展开更多
An analytical method was developed and validated for determination of patulin in apple puree by HPLC. Extraction and clean-up ofpatulin from clear extract are achieved on AFFINIMIP SPEPATULIN cartridges. Patulin is th...An analytical method was developed and validated for determination of patulin in apple puree by HPLC. Extraction and clean-up ofpatulin from clear extract are achieved on AFFINIMIP SPEPATULIN cartridges. Patulin is then separated on a Hypersil GOLD column 150 mm × 4 mm, 5 μtmand detected at 276 nm. The recovery in the range of 5 μg/kg-80 μg/kg was 81.47%. The limit of detection (LOD) was 1.36 μg/kg, and the limit of quantification (LOQ) was 4.55 μg/kg. The patulin content of the commercial samples of apple puree and samples of apple and fruit puree forinfants and young children as well as the samples of apple puree prepared from two apple varieties intended for processing (Jonathan, Florina) and obtained from conventional and uncertified organic cultures has been evaluated in this paper. The 44.83% patulin concentration of the analyzed samples were under the maximum level of the European Commission Regulation (EC) 1881/2006, in 46.55% of the analyzed samples patulin was not detected and in 8.62% of samples patulin concentration was lower than LOQ (European Comission, 2006a) Patulin was not detected in samples of apple puree intended for infants and young children consumption.展开更多
In this study,the effect of adding essential oil from different plants on prolonging the shelf life of pistachio puree was investigated.For this purpose,Rancimat method,which is one of the accelerated shelf-life test(...In this study,the effect of adding essential oil from different plants on prolonging the shelf life of pistachio puree was investigated.For this purpose,Rancimat method,which is one of the accelerated shelf-life test(ASLT)methods,was used to determine the effect of oregano(OO)and rosemary(RO)essential oils on the oxidative stability of pistachio puree.Butylated hydroxyanisole(BHA)and the control sample were used for the comparison.Concentrations used for essential oils and synthetic antioxidants were 150,300 and 600 ppm and 150 ppm,respectively.The conductivity was followed at three temperatures,110,120 and 130℃,with the addition of essential oils and BHA to pistachio puree during ASLT.Pistachio puree with essential oils showed protection against the lipid oxidation process.As the temperature increased induction time was significantly decreased during ASLT(p<0.05).The same concentrations of essential oils and BHA were also added into pistachio puree to observe the change in peroxide value(PV)and free fatty acid(FFA)value under normal storage temperatures 15,25 and 40℃.The PV and FFA increase were lower in RO,OO and BHA added pistachio puree samples during 8-month storage(p<0.05).Six hundred(600)ppm of RO added sample had an antioxidative effect as much as 150 ppm BHA added sample for both ASLT and normal storage conditions.These essential oils could be used as natural antioxidants in foods with high lipid content increasing the shelf life of these products.展开更多
Temperature effect was evaluated over the viscosity of commercial carrot puree in the range 30 to 60 ℃, using aBrookfield viscometer, model 4535, Lab-Line instruments. In order to perform the viscosity tests, 28 spec...Temperature effect was evaluated over the viscosity of commercial carrot puree in the range 30 to 60 ℃, using aBrookfield viscometer, model 4535, Lab-Line instruments. In order to perform the viscosity tests, 28 specimens of carrot puree froma local market were used. Totally, 72 tests (each one with a couple replicas) were performed during five minutes, using fourtemperatures (30, 40, 50 and 60 ℃), six shear rates (0.26, 0.52, 1.05, 2.09, 5.24 and 10.47 s1) and three spindles (4, 5 and 6).Statistical analysis was performed using LSD and Duncan tests with a confidence interval of 95% (p value of 0.05). In the currentstudy, it was observed that an increase in the temperature triggers a reduction in the viscosity of the carrot specimens analyzed,although the samples tested at 60℃ were deviated from this trend, which may be due to denaturation of the starch containing carrotsamples at such temperature. Multiple biochemical and micro-structural changes inside the food specimens may begin to occur belowand over the physiological range (20-45 ℃). Experimental data were analyzed with Power Law model in order to obtain the bestfitted parameters as a function of shear rate: It was observed that the consistent index (k) decreased with an increment in thetemperature; while all the values of parameter "n" lesser than one, which means that the puree samples behaved as a pseudo-plasticfluid. Besides that, an Arrhenius model was used to fit the parameters as a function of temperature: Parameter A was lower usingtheexperimental data at shear rates of 10.47 s-1. The modeling performed may be helpful for the appropriate selection of some processvariables, as the shear rate and operation temperature, used for the production of carrot puree; all this is in order to obtain the finishedproduct with the desired consistency.展开更多
Coconut (Cocos nucifera) milk-based ice cream is one of the innovative non-dairy milk products gaining popularity among consumers. The objective was to develop coconut milk-based ice cream incorporated with soursop (A...Coconut (Cocos nucifera) milk-based ice cream is one of the innovative non-dairy milk products gaining popularity among consumers. The objective was to develop coconut milk-based ice cream incorporated with soursop (Annona muricata) fruit puree and gum Arabic from Acacia senegal var. kerensis, conduct a sensory evaluation using descriptive tests by trained panelists (n = 9) then evaluate for consumer acceptability by semi trained panelists (n = 30). A seven-point hedonic scale for colour, taste, flavour, texture and overall acceptability was used. The data obtained was subjected to analysis of variance (ANOVA) and the means were separated to determine their significance differences. Principal Component Analysis (PCA) was done for factor reduction to make it easy for the multi-dimensional descriptive data to be interpreted. PCA results indicated that unit increase in soursop and gum Arabic in the ice cream led to 83.1% increase in starchy taste, 78.3% increase in consistency and 73.6% decrease in coconut aroma. For consumer acceptability test, the obtained results showed that, soursop puree addition at successive levels led to a statistically significant effect (p < 0.05) on colour, flavour, texture, taste and overall acceptability while of gum Arabic incorporation was not significant (p > 0.05) for all attributes. The effect due to interaction between gum Arabic and soursop puree at the different levels however was significant for colour, flavour and texture but not significant for taste and overall acceptability. Our results therefore point to a potential application of soursop fruit and gum Arabic as alternative ingredients in the manufacture of a non-dairy ice cream with desirable sensory properties that would expand the variety of options consumers can choose from.展开更多
Consumption of functional foods with health promoting benefits and/or disease prevention has been on the increase globally. The study aimed at evaluating the potential of utilizing Kenyan orange fleshed sweet potato ...Consumption of functional foods with health promoting benefits and/or disease prevention has been on the increase globally. The study aimed at evaluating the potential of utilizing Kenyan orange fleshed sweet potato (Ipomoea batatas Lam.) for functional food production with aesthetics benefits. Purees from three different varieties of orange fleshed sweet potato (OFSP) were analyzed for nutritional, physicochemical and microbial quality, The findings of the study show that the three purees were all microbiologically safe and of near neutral pH, but differed significantly (P 〈 0.05) in nutrient content (dry matter content, 12.76-28.23%; crude fiber, 1.37-2.90% fresh weight basis (FWB); 13-carotene, 0.94-9.27 mg/100g dry weight basis (DWB); starch, 10.20-18.30% FWB & total sugar 27.08-31.76% DWB). The purees had attractive appearance (ranging from yellow to dark orange), with varying significantly different spectrophotometer hunters color scale (P 〈 0.05), and flow ability. Conclusions from the findings show great potential of utilizing the varying properties of OFSP puree to produce enriched functional food products such as probiotic/prebiotic dairy, beverages, bakery and baby foods.展开更多
It has been a common method to improve the mechanical properties of metals by manipulating their microstructures via static recrystallization,i.e.,through heat treatment.Therefore,the knowledge of recrystallization an...It has been a common method to improve the mechanical properties of metals by manipulating their microstructures via static recrystallization,i.e.,through heat treatment.Therefore,the knowledge of recrystallization and grain growth is critical to the success of the technique.In the present work,by using in-situ high temperature EBSD,the mechanisms that control recrystallization and grain growth of an extruded pure Mg were studied.The experimental results revealed that the grains of priority for dynamic recrystallization exhibit fading competitiveness under static recrystallization.It is also found that grain boundary movement or grain growth is likely to show an inverse energy gradient effect,i.e.,low energy grains tend to swallow or grow into high energy grains,and grain boundaries of close to 30°exhibit superior growth advantage to others.Another finding is that{10-12}tensile twin boundaries are sites of hardly observed for recrystallization,and are finally swallowed by adjacent recrystallized grains.The above findings may give comprehensive insights of static recrystallization and grain growth of Mg,and may guide the design of advanced materials processing in microstructural engineering.展开更多
The Sonid Zuoqi ductile detachment zone is located at the southeastern margin of the Central Asian orogenic belt(CAOB),striking EW and dipping to the S.The major rock type of the Sonid Zuoqi ductile detachment zone is...The Sonid Zuoqi ductile detachment zone is located at the southeastern margin of the Central Asian orogenic belt(CAOB),striking EW and dipping to the S.The major rock type of the Sonid Zuoqi ductile detachment zone is mylonite derived from granite.The sequence of mylonite features is:(1)S and C foliations of mylonite,and(2)extensional crenulation cleavage(ecc)or C′and the kinematic vorticity(Wk)value changed from 0.70 to 0.95 and from 0.37 to 0.69,respectively;the strain type of the mylonites within the Sonid Zuoqi ductile detachment zone is compressional to planar strain.The strong deformation mylonite and Halatu plutons yielded a zircon U-Pb age of 244 Ma and a zircon(U-Th)/He age of 214 Ma,respectively.Based on the strain and kinematic vorticity analysis,together with the zircon U-Pb and zircon(U-Th)/He ages and the regional tectonic background,the study area experienced three stage evolution:tangential simpleshear(244 Ma),simple-shear-dominated general shear represented by upper crustal extension(224 Ma)and pure-shear-dominated general shear represented by the Halatu pluton doming(214 Ma),which constrained the early Mesozoic NE-SW crustal extension at the southeastern margin of the CAOB.This NE-SW extension probably originated from the postorogenic extensional collapse of the CAOB,subsequent exhumation being controlled by the far afield effects of the closure of the Mongol-Okhotsk belt.展开更多
The recrystallization behavior,grain boundary characteristic distribution,and mechanical properties of pure Cu sheets that were subjected to different cold rolling paths,and then annealed at 400°C for 10,30,60,an...The recrystallization behavior,grain boundary characteristic distribution,and mechanical properties of pure Cu sheets that were subjected to different cold rolling paths,and then annealed at 400°C for 10,30,60,and 420 min,were investigated.Different rolling paths changed the grain boundary orientations of cold-rolled copper,causing recrystallized grains to nucleate and grow in an oriented manner.However,the evolution of the texture indicated that cold-rolled copper with different rolling paths did not show an obvious preferred orientation after annealing.The RD-60 specimen exhibited the smallest grain size(6.6μm).The results indicated that the grain size and low-ΣCSL grain boundaries worked together to provide RD-60 samples with appropriate mechanical properties and high plasticity.The yield strength,ultimate tensile strength,and elongation of RD-60 sample were 81 MPa,230 MPa,and 49%,respectively.These results could provide guidance for tuning the microstructures and properties of pure Cu foils,as well as designing fabrication routes for pure Cu foils through processes such as rolling and drawing.展开更多
Incorporation of higher content Si anode material beyond 5 wt% to Li-ion batteries(LIBs)is challenging,owing to large volume change,swelling,and solid electrolyte interphase(SEI)instability issues.Herein,a strategy of...Incorporation of higher content Si anode material beyond 5 wt% to Li-ion batteries(LIBs)is challenging,owing to large volume change,swelling,and solid electrolyte interphase(SEI)instability issues.Herein,a strategy of diacetoxydimethylsilane(DAMS)additive-directed SEI stabilization is proposed for a stable operation of Si-0.33FeSi_(2)(named as Si-Fe)anode without graphite,which provides siloxane inorganics and organics enrichment that compensate insufficient passivation of fluoroethylene carbonate(FEC)additive and reduce a dependence on FEC.Unprecedented stable cycling performance of highly loaded(3.5 mA h cm^(-2))pure Si-Fe anode is achieved with 2 wt%DAMS combined with 9 wt%FEC additives under ambient pressure,yielding high capacity 1270 mA h g^(-1)at 0.5 C and significantly improved capacity retention of 81% after 100 cycles,whereas short circuit and rapid capacity fade occur with FEC only additive.DAMS-directed robust SEI layer dramatically suppresses swelling and particles crossover through separator,and therefore prevents short circuit,demonstrating a possible operation of pure Si or Sidominant anodes in the next-generation high-energy-density and safe LIBs.展开更多
To address the incompatibility between high environmental adaptability and deep subwavelength characteristics in conventional local resonance metamaterials,and overcome the deficiencies in the stability of existing ac...To address the incompatibility between high environmental adaptability and deep subwavelength characteristics in conventional local resonance metamaterials,and overcome the deficiencies in the stability of existing active control techniques for band gaps,this paper proposes a design method of pure metal vibration damping metamaterial with continuously tunable stiffness for wideband elastic wave absorption.We design a dual-helix narrow-slit pure metal metamaterial unit,which possesses the triple advantage of high spatial compactness,low stiffness characteristics,and high structural stability,enabling the opening of elastic flexural band gaps in the low-frequency range.Similar to the principle of a sliding rheostat,the introduction of continuously sliding plug-ins into the helical slits enables the continuous variation of the stiffness of the metamaterial unit,achieving a continuously tunable band gap effect.This successfully extends the effective band gap by more than ten times.The experimental results indicate that this metamaterial unit can be used as an additional vibration absorber to absorb the low-frequency vibration energy effectively.Furthermore,it advances the metamaterial absorbers from a purely passive narrowband design to a wideband tunable one.The pure metal double-helix metamaterials retain the subwavelength properties of metamaterials and are suitable for deployment in harsh environments.Simultaneously,by adjusting its stiffness,it substantially broadens the effective band gap range,presenting promising potential applications in various mechanical equipment operating under adverse conditions.展开更多
Electrocatalytic reduction of CO_(2) converts intermittent renewable electricity into value-added liquid products with an enticing prospect,but its practical application is hampered due to the lack of high-performance...Electrocatalytic reduction of CO_(2) converts intermittent renewable electricity into value-added liquid products with an enticing prospect,but its practical application is hampered due to the lack of high-performance electrocatalysts.Herein,we elaborately design and develop strongly coupled nanosheets composed of Ag nanoparticles and Sn-SnO_(2) grains,designated as Ag/Sn-SnO_(2) nanosheets(NSs),which possess optimized electronic structure,high electrical conductivity,and more accessible sites.As a result,such a catalyst exhibits unprecedented catalytic performance toward CO_(2)-to-formate conversion with near-unity faradaic efficiency(≥90%),ultrahigh partial current density(2,000 mA cm^(−2)),and superior long-term stability(200 mA cm^(−2),200 h),surpassing the reported catalysts of CO_(2) electroreduction to formate.Additionally,in situ attenuated total reflection-infrared spectra combined with theoretical calculations revealed that electron-enriched Sn sites on Ag/Sn-SnO_(2)NSs not only promote the formation of*OCHO and alleviate the energy barriers of*OCHO to*HCOOH,but also impede the desorption of H*.Notably,the Ag/Sn-SnO_(2)NSs as the cathode in a membrane electrode assembly with porous solid electrolyte layer reactor can continuously produce~0.12 M pure HCOOH solution at 100 mA cm^(−2)over 200 h.This work may inspire further development of advanced electrocatalysts and innovative device systems for promoting practical application of producing liquid fuels from CO_(2).展开更多
Based on the production curves,changes in hydrocarbon composition and quantities over time,and production systems from key trial production wells in lacustrine shale oil areas in China,fine fraction cutting experiment...Based on the production curves,changes in hydrocarbon composition and quantities over time,and production systems from key trial production wells in lacustrine shale oil areas in China,fine fraction cutting experiments and molecular dynamics numerical simulations were conducted to investigate the effects of changes in shale oil composition on macroscopic fluidity.The concept of“component flow”for shale oil was proposed,and the formation mechanism and conditions of component flow were discussed.The research reveals findings in four aspects.First,a miscible state of light,medium and heavy hydrocarbons form within micropores/nanopores of underground shale according to similarity and intermiscibility principles,which make components with poor fluidity suspended as molecular aggregates in light and medium hydrocarbon solvents,such as heavy hydrocarbons,thereby decreasing shale oil viscosity and enhancing fluidity and outflows.Second,small-molecule aromatic hydrocarbons act as carriers for component flow,and the higher the content of gaseous and light hydrocarbons,the more conducive it is to inhibit the formation of larger aggregates of heavy components such as resin and asphalt,thus increasing their plastic deformation ability and bringing about better component flow efficiency.Third,higher formation temperatures reduce the viscosity of heavy hydrocarbon components,such as wax,thereby improving their fluidity.Fourth,preservation conditions,formation energy,and production system play important roles in controlling the content of light hydrocarbon components,outflow rate,and forming stable“component flow”,which are crucial factors for the optimal compatibility and maximum flow rate of multi-component hydrocarbons in shale oil.The component flow of underground shale oil is significant for improving single-well production and the cumulative ultimate recovery of shale oil.展开更多
BACKGROUND Numerous studies have found that patients experiencing sudden sensorineural hearing loss(SSHL),with or without accompanying vertigo,often show impaired vestibular function.However,there is a dearth of studi...BACKGROUND Numerous studies have found that patients experiencing sudden sensorineural hearing loss(SSHL),with or without accompanying vertigo,often show impaired vestibular function.However,there is a dearth of studies analyzing vestibularevoked myogenic potentials(VEMPs)in SSHL patients across various age groups.AIM To investigate vestibular condition in SSHL patients across various age demographics.METHODS Clinical data of 84 SSHL patients were investigated retrospectively.Audiometry,cervical vestibular evoked myogenic potentials(c-VEMPs),and ocular vestibular evoked myogenic potentials(o-VEMPs)were conducted on these patients.Parameters assessed included the latencies of P1 and N1 waves,as well as the amplitudes of P1–N1 waves.Moreover,the study evaluated the influence of factors such as sex,affected side,configuration of hearing loss,and presence of accompanying vertigo.RESULTS Among the 84 SSHL patients,no significant differences were observed among the three groups in terms of gender,affected side,and the presence or absence of vertigo.Group II(aged 41–60 years)had the highest number of SSHL cases.The rates of absent o-VEMPs in the affected ears were 20.83%,31.58%,and 22.72%for the three age groups,respectively,with no statistically significant difference among them.The rates of absent c-VEMPs in the affected ears were 8.3%,34.21%,and 18.18%for the three age groups,respectively,with significant differences.In the unaffected ears,there were differences observed in the extraction rates of o-VEMPs in the unaffected ears among the age groups.In the three age groups,no significant differences were noted in the three age groups in the latencies of P1 and N1 waves or in the amplitude of N1–P1 waves for c-VEMPs and o-VEMPs,either on the affected side or on the unaffected side,across the three age groups.CONCLUSION The extraction rate of VEMPs is more valuable than parameters.Regardless of the presence of vertigo,vestibular organs are involved in SSHL.Notably,SSHL patients aged 41–60 appear more susceptible to damage to the inferior vestibular nerve and saccule.展开更多
Electric vehicles use electric motors, which turn electrical energy into mechanical energy. As electric motors are conventionally used in all the industry, it is an established development site. It’s a mature technol...Electric vehicles use electric motors, which turn electrical energy into mechanical energy. As electric motors are conventionally used in all the industry, it is an established development site. It’s a mature technology with ideal power and torque curves for vehicular operation. Conventional vehicles use oil and gas as fuel or energy storage. Although they also have an excellent economic impact, the continuous use of oil and gas threatened the world’s reservation of total oil and gas. Also, they emit carbon dioxide and some toxic ingredients through the vehicle’s tailpipe, which causes the greenhouse effect and seriously impacts the environment. So, as an alternative, electric car refers to a green technology of decarbonization with zero emission of greenhouse gases through the tailpipe. So, they can remove the problem of greenhouse gas emissions and solve the world’s remaining non-renewable energy storage problem. Pure electric vehicles (PEV) can be applied in all spheres, but their special implementation can only be seen in downhole operations. They are used for low noise and less pollution in the downhole process. In this study, the basic structure of the pure electric command vehicle is studied, the main components of the command vehicle power system, namely the selection of the drive motor and the power battery, are analyzed, and the main parameters of the drive motor and the power battery are designed and calculated. The checking calculation results show that the power and transmission system developed in this paper meets the design requirements, and the design scheme is feasible and reasonable.展开更多
为降低汽车运输船(Pure Car Truck Carrier,PCTC)的噪声,减小其电力消耗,对风机房和风道的主要组成部分、独立风机房和结构风机房的不同的特点进行分析,并对货舱内部流场、通风阻力、噪声控制等3方面的关键技术进行研究。结果表明:货舱...为降低汽车运输船(Pure Car Truck Carrier,PCTC)的噪声,减小其电力消耗,对风机房和风道的主要组成部分、独立风机房和结构风机房的不同的特点进行分析,并对货舱内部流场、通风阻力、噪声控制等3方面的关键技术进行研究。结果表明:货舱内部流场主要取决于通风总体方案;控制风道通风阻力是设计的关键,对风机房选型和控制噪声有很大影响;计算流体力学(Computational Fluid Dynamics,CFD)分析可有效提高设计的准确性。研究成果可为PCTC货舱通风设计提供一定参考。展开更多
The cobalt ferrite nanoparticles were prepared by coprecipitation in the presence of poly (N-vinylpyrrolidone) (PVP) and characterized by XRD, TEM, EDX and magnetometry. XRD results suggest the formation of pure cobal...The cobalt ferrite nanoparticles were prepared by coprecipitation in the presence of poly (N-vinylpyrrolidone) (PVP) and characterized by XRD, TEM, EDX and magnetometry. XRD results suggest the formation of pure cobalt ferrite. The mean particle sizes of CoFe2O4 samples annealed at 400 ℃ and 600 ℃ were ca. 6 and 25 nm, respectively as obtained by transmission electron microscopy (TEM). The magnetic measurements indicated that nano-particles obtained at 400 ℃ were superparamagnetic while that prepared at 600 ℃ were ferrimagnetic.展开更多
The development of microstructure and texture during cold deep drawing of commercially pure titanium(CP-Ti) was investigated.Three parts,stretching region,drawing region and flange region,were sequentially formed in...The development of microstructure and texture during cold deep drawing of commercially pure titanium(CP-Ti) was investigated.Three parts,stretching region,drawing region and flange region,were sequentially formed in the deep drawing process of the hemispheric surface part,with reference to deformation modes and strain regimes.Results show that the plastic strain is accommodated by dislocation slip and deformation twinning in the whole deep drawing process.The texture of the CP-Ti sheet and its drawn part consists of rolling texture component and recrystallization texture component.The intensity and type of the initial texture varied during the drawing process are related to the production of deformation twinning and dislocation slip.Twinning weakens the initial texture by randomizing the orientations of crystals,especially for the recrystallization texture.The recrystallization texture in the drawing region disappears due to the significant forming of twinning.Furthermore,over drawing would result in the predominance of dislocation slip and the texture is strengthened.展开更多
Cu matrix composite reinforced with 10%(volume fraction) carbon nanotubes(CNTs/Cu) and pure Cu bulk were prepared by powder metallurgy techniques under the same consolidation processing condition.The effect of ele...Cu matrix composite reinforced with 10%(volume fraction) carbon nanotubes(CNTs/Cu) and pure Cu bulk were prepared by powder metallurgy techniques under the same consolidation processing condition.The effect of electrical current on tribological property of the materials was investigated by using a pin-on-disk friction and wear tester.The results show that the friction coefficient and wear rate of CNTs/Cu composite as well as those of pure Cu bulk increase with increasing the electrical current without exception,and the effect of electrical current is more obvious on tribological property of pure Cu bulk than on that of CNTs/Cu composite;the dominant wear mechanisms are arc erosion wear and plastic flow deformation,respectively;CNTs can improve tribological property of Cu matrix composites with electrical current.展开更多
基金Supported by the National Natural Science Foundation of China(32072352)。
文摘To improve drying uniformity and anthocyanin content of the raspberry puree dried in a continuous microwave dryer,the effects of process parameters(microwave intensity,air velocity,and drying time)on evaluation indexes(average temperature,average moisture content,average retention rate of the total anthocyanin content,temperature contrast value,and moisture dispersion value)were investigated via the response surface method(RSM)and the artificial neural network(ANN)with genetic algorithm(GA).The results showed that the microwave intensity and drying time dominated the changes of evaluation indexes.Overall,the ANN model was superior to the RSM model with better estimation ability,and higher drying uniformity and anthocyanin retention rate were achieved for the ANN-GA model compared with RSM.The optimal parameters were microwave intensity of 5.53 W•g^(-1),air velocity of 1.22 m·s^(-1),and drying time of 5.85 min.This study might provide guidance for process optimization of microwave drying berry fruits.
文摘AIM: To identify the cut-off value for predicting the ability of elderly patients with dysphagia to swallow pureed diets using a new endoscopy scoring method. METHODS: Endoscopic swallowing evaluation of pureed diets were done in patients ≥ 65 years with dysphagia. The Hyodo-Komagane score for endoscopic swallowing evaluation is expressed as the sum(0-12) of four degrees(0-3) with four parameters:(1) salivary pooling in the vallecula and piriform sinuses;(2) the response of glottal closure reflex induced by touching the epiglottis with the endoscope;(3) the location of the bolus at the time of swallow onset assessed by "white-out" following swallowing of test jelly; and(4) pharyngeal clearance after swallowing of test jelly. We used receiver operating characteristic(ROC) curve analysis to retrospectively analyze the association between the total score and successful oral intake of pureed diets. RESULTS: One hundred and seventy-eight patients were enrolled including 113 men(63%), mean age 83 years(range, 66-98). One hundred and twenty-six patients(71%) were able to eat pureed diets during the observation period(mean ± SD, 19 ± 14 d). In ROC analysis, the cut-off value of the score for eating the pureed diets was 7(sensitivity = 0.98; specificity = 0.91).CONCLUSION: The Hyodo-Komagane endoscopic score is useful to predict the ability to eat pureed diets in elderly patients with dysphagia.
文摘An analytical method was developed and validated for determination of patulin in apple puree by HPLC. Extraction and clean-up ofpatulin from clear extract are achieved on AFFINIMIP SPEPATULIN cartridges. Patulin is then separated on a Hypersil GOLD column 150 mm × 4 mm, 5 μtmand detected at 276 nm. The recovery in the range of 5 μg/kg-80 μg/kg was 81.47%. The limit of detection (LOD) was 1.36 μg/kg, and the limit of quantification (LOQ) was 4.55 μg/kg. The patulin content of the commercial samples of apple puree and samples of apple and fruit puree forinfants and young children as well as the samples of apple puree prepared from two apple varieties intended for processing (Jonathan, Florina) and obtained from conventional and uncertified organic cultures has been evaluated in this paper. The 44.83% patulin concentration of the analyzed samples were under the maximum level of the European Commission Regulation (EC) 1881/2006, in 46.55% of the analyzed samples patulin was not detected and in 8.62% of samples patulin concentration was lower than LOQ (European Comission, 2006a) Patulin was not detected in samples of apple puree intended for infants and young children consumption.
文摘In this study,the effect of adding essential oil from different plants on prolonging the shelf life of pistachio puree was investigated.For this purpose,Rancimat method,which is one of the accelerated shelf-life test(ASLT)methods,was used to determine the effect of oregano(OO)and rosemary(RO)essential oils on the oxidative stability of pistachio puree.Butylated hydroxyanisole(BHA)and the control sample were used for the comparison.Concentrations used for essential oils and synthetic antioxidants were 150,300 and 600 ppm and 150 ppm,respectively.The conductivity was followed at three temperatures,110,120 and 130℃,with the addition of essential oils and BHA to pistachio puree during ASLT.Pistachio puree with essential oils showed protection against the lipid oxidation process.As the temperature increased induction time was significantly decreased during ASLT(p<0.05).The same concentrations of essential oils and BHA were also added into pistachio puree to observe the change in peroxide value(PV)and free fatty acid(FFA)value under normal storage temperatures 15,25 and 40℃.The PV and FFA increase were lower in RO,OO and BHA added pistachio puree samples during 8-month storage(p<0.05).Six hundred(600)ppm of RO added sample had an antioxidative effect as much as 150 ppm BHA added sample for both ASLT and normal storage conditions.These essential oils could be used as natural antioxidants in foods with high lipid content increasing the shelf life of these products.
文摘Temperature effect was evaluated over the viscosity of commercial carrot puree in the range 30 to 60 ℃, using aBrookfield viscometer, model 4535, Lab-Line instruments. In order to perform the viscosity tests, 28 specimens of carrot puree froma local market were used. Totally, 72 tests (each one with a couple replicas) were performed during five minutes, using fourtemperatures (30, 40, 50 and 60 ℃), six shear rates (0.26, 0.52, 1.05, 2.09, 5.24 and 10.47 s1) and three spindles (4, 5 and 6).Statistical analysis was performed using LSD and Duncan tests with a confidence interval of 95% (p value of 0.05). In the currentstudy, it was observed that an increase in the temperature triggers a reduction in the viscosity of the carrot specimens analyzed,although the samples tested at 60℃ were deviated from this trend, which may be due to denaturation of the starch containing carrotsamples at such temperature. Multiple biochemical and micro-structural changes inside the food specimens may begin to occur belowand over the physiological range (20-45 ℃). Experimental data were analyzed with Power Law model in order to obtain the bestfitted parameters as a function of shear rate: It was observed that the consistent index (k) decreased with an increment in thetemperature; while all the values of parameter "n" lesser than one, which means that the puree samples behaved as a pseudo-plasticfluid. Besides that, an Arrhenius model was used to fit the parameters as a function of temperature: Parameter A was lower usingtheexperimental data at shear rates of 10.47 s-1. The modeling performed may be helpful for the appropriate selection of some processvariables, as the shear rate and operation temperature, used for the production of carrot puree; all this is in order to obtain the finishedproduct with the desired consistency.
文摘Coconut (Cocos nucifera) milk-based ice cream is one of the innovative non-dairy milk products gaining popularity among consumers. The objective was to develop coconut milk-based ice cream incorporated with soursop (Annona muricata) fruit puree and gum Arabic from Acacia senegal var. kerensis, conduct a sensory evaluation using descriptive tests by trained panelists (n = 9) then evaluate for consumer acceptability by semi trained panelists (n = 30). A seven-point hedonic scale for colour, taste, flavour, texture and overall acceptability was used. The data obtained was subjected to analysis of variance (ANOVA) and the means were separated to determine their significance differences. Principal Component Analysis (PCA) was done for factor reduction to make it easy for the multi-dimensional descriptive data to be interpreted. PCA results indicated that unit increase in soursop and gum Arabic in the ice cream led to 83.1% increase in starchy taste, 78.3% increase in consistency and 73.6% decrease in coconut aroma. For consumer acceptability test, the obtained results showed that, soursop puree addition at successive levels led to a statistically significant effect (p < 0.05) on colour, flavour, texture, taste and overall acceptability while of gum Arabic incorporation was not significant (p > 0.05) for all attributes. The effect due to interaction between gum Arabic and soursop puree at the different levels however was significant for colour, flavour and texture but not significant for taste and overall acceptability. Our results therefore point to a potential application of soursop fruit and gum Arabic as alternative ingredients in the manufacture of a non-dairy ice cream with desirable sensory properties that would expand the variety of options consumers can choose from.
文摘Consumption of functional foods with health promoting benefits and/or disease prevention has been on the increase globally. The study aimed at evaluating the potential of utilizing Kenyan orange fleshed sweet potato (Ipomoea batatas Lam.) for functional food production with aesthetics benefits. Purees from three different varieties of orange fleshed sweet potato (OFSP) were analyzed for nutritional, physicochemical and microbial quality, The findings of the study show that the three purees were all microbiologically safe and of near neutral pH, but differed significantly (P 〈 0.05) in nutrient content (dry matter content, 12.76-28.23%; crude fiber, 1.37-2.90% fresh weight basis (FWB); 13-carotene, 0.94-9.27 mg/100g dry weight basis (DWB); starch, 10.20-18.30% FWB & total sugar 27.08-31.76% DWB). The purees had attractive appearance (ranging from yellow to dark orange), with varying significantly different spectrophotometer hunters color scale (P 〈 0.05), and flow ability. Conclusions from the findings show great potential of utilizing the varying properties of OFSP puree to produce enriched functional food products such as probiotic/prebiotic dairy, beverages, bakery and baby foods.
文摘It has been a common method to improve the mechanical properties of metals by manipulating their microstructures via static recrystallization,i.e.,through heat treatment.Therefore,the knowledge of recrystallization and grain growth is critical to the success of the technique.In the present work,by using in-situ high temperature EBSD,the mechanisms that control recrystallization and grain growth of an extruded pure Mg were studied.The experimental results revealed that the grains of priority for dynamic recrystallization exhibit fading competitiveness under static recrystallization.It is also found that grain boundary movement or grain growth is likely to show an inverse energy gradient effect,i.e.,low energy grains tend to swallow or grow into high energy grains,and grain boundaries of close to 30°exhibit superior growth advantage to others.Another finding is that{10-12}tensile twin boundaries are sites of hardly observed for recrystallization,and are finally swallowed by adjacent recrystallized grains.The above findings may give comprehensive insights of static recrystallization and grain growth of Mg,and may guide the design of advanced materials processing in microstructural engineering.
基金supported by the National Natural Science Foundation of China(Grant No.41662014)。
文摘The Sonid Zuoqi ductile detachment zone is located at the southeastern margin of the Central Asian orogenic belt(CAOB),striking EW and dipping to the S.The major rock type of the Sonid Zuoqi ductile detachment zone is mylonite derived from granite.The sequence of mylonite features is:(1)S and C foliations of mylonite,and(2)extensional crenulation cleavage(ecc)or C′and the kinematic vorticity(Wk)value changed from 0.70 to 0.95 and from 0.37 to 0.69,respectively;the strain type of the mylonites within the Sonid Zuoqi ductile detachment zone is compressional to planar strain.The strong deformation mylonite and Halatu plutons yielded a zircon U-Pb age of 244 Ma and a zircon(U-Th)/He age of 214 Ma,respectively.Based on the strain and kinematic vorticity analysis,together with the zircon U-Pb and zircon(U-Th)/He ages and the regional tectonic background,the study area experienced three stage evolution:tangential simpleshear(244 Ma),simple-shear-dominated general shear represented by upper crustal extension(224 Ma)and pure-shear-dominated general shear represented by the Halatu pluton doming(214 Ma),which constrained the early Mesozoic NE-SW crustal extension at the southeastern margin of the CAOB.This NE-SW extension probably originated from the postorogenic extensional collapse of the CAOB,subsequent exhumation being controlled by the far afield effects of the closure of the Mongol-Okhotsk belt.
基金financially supported by the National Natural Science Foundation of China(No.52201099)the Scientific Research Starting Foundation of Anhui Polytechnic University,China(No.S022021004)+2 种基金Undergraduate Scientific Research Project of Anhui Polytechnic University,ChinaSchool Level Scientific Research Project of Anhui Polytechnic University,China(No.Xjky2022028)the Open Research Fund of Anhui Key Laboratory of High-Performance Non-ferrous Metal Materials,China(No.YSJS-2023-1)。
文摘The recrystallization behavior,grain boundary characteristic distribution,and mechanical properties of pure Cu sheets that were subjected to different cold rolling paths,and then annealed at 400°C for 10,30,60,and 420 min,were investigated.Different rolling paths changed the grain boundary orientations of cold-rolled copper,causing recrystallized grains to nucleate and grow in an oriented manner.However,the evolution of the texture indicated that cold-rolled copper with different rolling paths did not show an obvious preferred orientation after annealing.The RD-60 specimen exhibited the smallest grain size(6.6μm).The results indicated that the grain size and low-ΣCSL grain boundaries worked together to provide RD-60 samples with appropriate mechanical properties and high plasticity.The yield strength,ultimate tensile strength,and elongation of RD-60 sample were 81 MPa,230 MPa,and 49%,respectively.These results could provide guidance for tuning the microstructures and properties of pure Cu foils,as well as designing fabrication routes for pure Cu foils through processes such as rolling and drawing.
基金supported by the National Research Foundation grants funded by the Ministry of Science and ICT of Korea(2021M3H4A3A02086211 and RS-2023-00217581).
文摘Incorporation of higher content Si anode material beyond 5 wt% to Li-ion batteries(LIBs)is challenging,owing to large volume change,swelling,and solid electrolyte interphase(SEI)instability issues.Herein,a strategy of diacetoxydimethylsilane(DAMS)additive-directed SEI stabilization is proposed for a stable operation of Si-0.33FeSi_(2)(named as Si-Fe)anode without graphite,which provides siloxane inorganics and organics enrichment that compensate insufficient passivation of fluoroethylene carbonate(FEC)additive and reduce a dependence on FEC.Unprecedented stable cycling performance of highly loaded(3.5 mA h cm^(-2))pure Si-Fe anode is achieved with 2 wt%DAMS combined with 9 wt%FEC additives under ambient pressure,yielding high capacity 1270 mA h g^(-1)at 0.5 C and significantly improved capacity retention of 81% after 100 cycles,whereas short circuit and rapid capacity fade occur with FEC only additive.DAMS-directed robust SEI layer dramatically suppresses swelling and particles crossover through separator,and therefore prevents short circuit,demonstrating a possible operation of pure Si or Sidominant anodes in the next-generation high-energy-density and safe LIBs.
基金supported by the National Natural Science Foundation of China(No.52250287)the Outstanding Youth Science Fund Project of Shaanxi Province of China(No.2024JC-JCQN-49)。
文摘To address the incompatibility between high environmental adaptability and deep subwavelength characteristics in conventional local resonance metamaterials,and overcome the deficiencies in the stability of existing active control techniques for band gaps,this paper proposes a design method of pure metal vibration damping metamaterial with continuously tunable stiffness for wideband elastic wave absorption.We design a dual-helix narrow-slit pure metal metamaterial unit,which possesses the triple advantage of high spatial compactness,low stiffness characteristics,and high structural stability,enabling the opening of elastic flexural band gaps in the low-frequency range.Similar to the principle of a sliding rheostat,the introduction of continuously sliding plug-ins into the helical slits enables the continuous variation of the stiffness of the metamaterial unit,achieving a continuously tunable band gap effect.This successfully extends the effective band gap by more than ten times.The experimental results indicate that this metamaterial unit can be used as an additional vibration absorber to absorb the low-frequency vibration energy effectively.Furthermore,it advances the metamaterial absorbers from a purely passive narrowband design to a wideband tunable one.The pure metal double-helix metamaterials retain the subwavelength properties of metamaterials and are suitable for deployment in harsh environments.Simultaneously,by adjusting its stiffness,it substantially broadens the effective band gap range,presenting promising potential applications in various mechanical equipment operating under adverse conditions.
基金the National Science Fund for Distinguished Young Scholars(Grant No.52125103)the National Natural Science Foundation of China(Grant Nos.52301232,52071041,12074048,and 12147102)China Postdoctoral Science Foundation(Grant No.2022M720552).
文摘Electrocatalytic reduction of CO_(2) converts intermittent renewable electricity into value-added liquid products with an enticing prospect,but its practical application is hampered due to the lack of high-performance electrocatalysts.Herein,we elaborately design and develop strongly coupled nanosheets composed of Ag nanoparticles and Sn-SnO_(2) grains,designated as Ag/Sn-SnO_(2) nanosheets(NSs),which possess optimized electronic structure,high electrical conductivity,and more accessible sites.As a result,such a catalyst exhibits unprecedented catalytic performance toward CO_(2)-to-formate conversion with near-unity faradaic efficiency(≥90%),ultrahigh partial current density(2,000 mA cm^(−2)),and superior long-term stability(200 mA cm^(−2),200 h),surpassing the reported catalysts of CO_(2) electroreduction to formate.Additionally,in situ attenuated total reflection-infrared spectra combined with theoretical calculations revealed that electron-enriched Sn sites on Ag/Sn-SnO_(2)NSs not only promote the formation of*OCHO and alleviate the energy barriers of*OCHO to*HCOOH,but also impede the desorption of H*.Notably,the Ag/Sn-SnO_(2)NSs as the cathode in a membrane electrode assembly with porous solid electrolyte layer reactor can continuously produce~0.12 M pure HCOOH solution at 100 mA cm^(−2)over 200 h.This work may inspire further development of advanced electrocatalysts and innovative device systems for promoting practical application of producing liquid fuels from CO_(2).
基金Supported by the National Natural Science Foundation of China(U22B6004)Scientific Research and Technological Development Project of RIPED(2022yjcq03)Technology Research Project of PetroChina Changqing Oilfield Company(KJZX2023-01)。
文摘Based on the production curves,changes in hydrocarbon composition and quantities over time,and production systems from key trial production wells in lacustrine shale oil areas in China,fine fraction cutting experiments and molecular dynamics numerical simulations were conducted to investigate the effects of changes in shale oil composition on macroscopic fluidity.The concept of“component flow”for shale oil was proposed,and the formation mechanism and conditions of component flow were discussed.The research reveals findings in four aspects.First,a miscible state of light,medium and heavy hydrocarbons form within micropores/nanopores of underground shale according to similarity and intermiscibility principles,which make components with poor fluidity suspended as molecular aggregates in light and medium hydrocarbon solvents,such as heavy hydrocarbons,thereby decreasing shale oil viscosity and enhancing fluidity and outflows.Second,small-molecule aromatic hydrocarbons act as carriers for component flow,and the higher the content of gaseous and light hydrocarbons,the more conducive it is to inhibit the formation of larger aggregates of heavy components such as resin and asphalt,thus increasing their plastic deformation ability and bringing about better component flow efficiency.Third,higher formation temperatures reduce the viscosity of heavy hydrocarbon components,such as wax,thereby improving their fluidity.Fourth,preservation conditions,formation energy,and production system play important roles in controlling the content of light hydrocarbon components,outflow rate,and forming stable“component flow”,which are crucial factors for the optimal compatibility and maximum flow rate of multi-component hydrocarbons in shale oil.The component flow of underground shale oil is significant for improving single-well production and the cumulative ultimate recovery of shale oil.
基金the Innovative Program of Hebei Provincial Eye Hospital,No.2023ZZ107.
文摘BACKGROUND Numerous studies have found that patients experiencing sudden sensorineural hearing loss(SSHL),with or without accompanying vertigo,often show impaired vestibular function.However,there is a dearth of studies analyzing vestibularevoked myogenic potentials(VEMPs)in SSHL patients across various age groups.AIM To investigate vestibular condition in SSHL patients across various age demographics.METHODS Clinical data of 84 SSHL patients were investigated retrospectively.Audiometry,cervical vestibular evoked myogenic potentials(c-VEMPs),and ocular vestibular evoked myogenic potentials(o-VEMPs)were conducted on these patients.Parameters assessed included the latencies of P1 and N1 waves,as well as the amplitudes of P1–N1 waves.Moreover,the study evaluated the influence of factors such as sex,affected side,configuration of hearing loss,and presence of accompanying vertigo.RESULTS Among the 84 SSHL patients,no significant differences were observed among the three groups in terms of gender,affected side,and the presence or absence of vertigo.Group II(aged 41–60 years)had the highest number of SSHL cases.The rates of absent o-VEMPs in the affected ears were 20.83%,31.58%,and 22.72%for the three age groups,respectively,with no statistically significant difference among them.The rates of absent c-VEMPs in the affected ears were 8.3%,34.21%,and 18.18%for the three age groups,respectively,with significant differences.In the unaffected ears,there were differences observed in the extraction rates of o-VEMPs in the unaffected ears among the age groups.In the three age groups,no significant differences were noted in the three age groups in the latencies of P1 and N1 waves or in the amplitude of N1–P1 waves for c-VEMPs and o-VEMPs,either on the affected side or on the unaffected side,across the three age groups.CONCLUSION The extraction rate of VEMPs is more valuable than parameters.Regardless of the presence of vertigo,vestibular organs are involved in SSHL.Notably,SSHL patients aged 41–60 appear more susceptible to damage to the inferior vestibular nerve and saccule.
文摘Electric vehicles use electric motors, which turn electrical energy into mechanical energy. As electric motors are conventionally used in all the industry, it is an established development site. It’s a mature technology with ideal power and torque curves for vehicular operation. Conventional vehicles use oil and gas as fuel or energy storage. Although they also have an excellent economic impact, the continuous use of oil and gas threatened the world’s reservation of total oil and gas. Also, they emit carbon dioxide and some toxic ingredients through the vehicle’s tailpipe, which causes the greenhouse effect and seriously impacts the environment. So, as an alternative, electric car refers to a green technology of decarbonization with zero emission of greenhouse gases through the tailpipe. So, they can remove the problem of greenhouse gas emissions and solve the world’s remaining non-renewable energy storage problem. Pure electric vehicles (PEV) can be applied in all spheres, but their special implementation can only be seen in downhole operations. They are used for low noise and less pollution in the downhole process. In this study, the basic structure of the pure electric command vehicle is studied, the main components of the command vehicle power system, namely the selection of the drive motor and the power battery, are analyzed, and the main parameters of the drive motor and the power battery are designed and calculated. The checking calculation results show that the power and transmission system developed in this paper meets the design requirements, and the design scheme is feasible and reasonable.
文摘The cobalt ferrite nanoparticles were prepared by coprecipitation in the presence of poly (N-vinylpyrrolidone) (PVP) and characterized by XRD, TEM, EDX and magnetometry. XRD results suggest the formation of pure cobalt ferrite. The mean particle sizes of CoFe2O4 samples annealed at 400 ℃ and 600 ℃ were ca. 6 and 25 nm, respectively as obtained by transmission electron microscopy (TEM). The magnetic measurements indicated that nano-particles obtained at 400 ℃ were superparamagnetic while that prepared at 600 ℃ were ferrimagnetic.
基金Project(SKLSP200906) supported by the Fund of State Key Laboratory of Solidification Processing in NWPUProject(B08040) supported by Program of Introducing Talents of Discipline in the Project of Advanced Materials and Their Forming Technology
文摘The development of microstructure and texture during cold deep drawing of commercially pure titanium(CP-Ti) was investigated.Three parts,stretching region,drawing region and flange region,were sequentially formed in the deep drawing process of the hemispheric surface part,with reference to deformation modes and strain regimes.Results show that the plastic strain is accommodated by dislocation slip and deformation twinning in the whole deep drawing process.The texture of the CP-Ti sheet and its drawn part consists of rolling texture component and recrystallization texture component.The intensity and type of the initial texture varied during the drawing process are related to the production of deformation twinning and dislocation slip.Twinning weakens the initial texture by randomizing the orientations of crystals,especially for the recrystallization texture.The recrystallization texture in the drawing region disappears due to the significant forming of twinning.Furthermore,over drawing would result in the predominance of dislocation slip and the texture is strengthened.
基金Project(2007CB607603)supported by the National Basic Research Program of China
文摘Cu matrix composite reinforced with 10%(volume fraction) carbon nanotubes(CNTs/Cu) and pure Cu bulk were prepared by powder metallurgy techniques under the same consolidation processing condition.The effect of electrical current on tribological property of the materials was investigated by using a pin-on-disk friction and wear tester.The results show that the friction coefficient and wear rate of CNTs/Cu composite as well as those of pure Cu bulk increase with increasing the electrical current without exception,and the effect of electrical current is more obvious on tribological property of pure Cu bulk than on that of CNTs/Cu composite;the dominant wear mechanisms are arc erosion wear and plastic flow deformation,respectively;CNTs can improve tribological property of Cu matrix composites with electrical current.