Background: Missions organized by international societies and humanitarian organizations play a significant role in saving many patients’ lives and improving their quality of life, despite the surrounding frustrating...Background: Missions organized by international societies and humanitarian organizations play a significant role in saving many patients’ lives and improving their quality of life, despite the surrounding frustrating conditions. Methods: A team of plastic surgery volunteers was sent to Yemen by the KSHARC. Results: A successful mission was performed on 62 patients who underwent surgery, with more than 900 patients examined and receiving appropriate medications. Conclusion: Missions in disaster-affected areas are of great importance. The role of missions and humanitarian organizations should be empowered.展开更多
BACKGROUND As artificial intelligence(AI)continues to expand across medical specialties,its application in medical imaging within plastic and reconstructive surgery(PRS)remains limited in the literature.Imaging plays ...BACKGROUND As artificial intelligence(AI)continues to expand across medical specialties,its application in medical imaging within plastic and reconstructive surgery(PRS)remains limited in the literature.Imaging plays a critical role in surgical planning,intraoperative decision-making,and postoperative monitoring in PRS,presenting an opportunity for AI to enhance clinical outcomes.AIM To evaluate the current applications of AI in medical imaging for plastic surgery,with a focus on its use in preoperative planning,intraoperative guidance,and postoperative monitoring.METHODS A literature search was conducted using MEDLINE,EMBASE,ScienceDirect,and OVID up to February 2025.Studies were included based on relevance to AI use in plastic surgery imaging.Extracted data included AI modality,surgical context,outcomes,and limitations.The search followed PRISMA guidelines and was registered with PROSPERO(CRD420251008741).RESULTS AI tools have improved preoperative planning through three-dimensional vascular mapping,augmented reality,and thermographic imaging.Intraoperatively,AI-enabled navigation and robotic systems have increased surgical precision.Postoperative AI applications,including deep learning algorithms and sensorbased monitoring,support early complication detection and wound healing assessment.However,persistent barriers include data variability,model generalizability,surgeon unfamiliarity,and lack of regulatory standards.CONCLUSION AI-driven imaging technologies show promise in enhancing decision-making and outcomes in PRS.To ensure safe clinical integration,future efforts must focus on structured validation,standardization,and ethical oversight.展开更多
Objective:To explore the clinical application effect of autologous fat granule transplantation in facial depression plastic surgery.Methods:A total of 98 patients with facial depression admitted to the plastic surgery...Objective:To explore the clinical application effect of autologous fat granule transplantation in facial depression plastic surgery.Methods:A total of 98 patients with facial depression admitted to the plastic surgery department of our hospital from January 2021 to December 2023 were selected and divided into observation group(49 cases)and control group(49 cases)according to the random number table method.The observation group was treated with autologous fat granule transplantation,while the control group was treated with hyaluronic acid filling.The total effective rate of treatment,incidence of postoperative complications,improvement indicators of facial morphology(depth of depression,symmetry),and effect maintenance rate after 6 months of follow-up were compared between the two groups.Results:The total effective rate of treatment in the observation group was 93.88%(46/49),which was significantly higher than that in the control group(79.59%,39/49)(P<0.05).The incidence of postoperative complications in the observation group was 6.12%(3/49),which was lower than that in the control group(20.41%,10/49)(P<0.05).One month after surgery,the depth of depression(1.23±0.31 mm)and symmetry(1.02±0.15 points)in the observation group were better than those in the control group(P<0.05).After 6 months of follow-up,the effect maintenance rate in the observation group was 89.80%(44/49),which was significantly higher than that in the control group(67.35%,33/49)(P<0.05).Conclusion:Autologous fat granule transplantation for the treatment of facial depression can significantly improve facial morphology,enhance treatment effect and patient satisfaction,reduce the incidence of complications,and maintain a more durable effect.It is a clinically preferred facial depression plastic surgery solution.展开更多
Background:This study explored the value of integrating problem-based learning(PBL)and team-based learning(TBL)methods into plastic and reconstructive surgery clinical practice.By addressing the challenges faced in tr...Background:This study explored the value of integrating problem-based learning(PBL)and team-based learning(TBL)methods into plastic and reconstructive surgery clinical practice.By addressing the challenges faced in traditional teachings,this study aimed to enhance educational outcomes and prepare students for real-world surgical scenarios,thereby improving patient care in this specialized field.Methods:Fifty undergraduate students majoring in clinical medicine at the Shanghai Jiao Tong University School of Medicine were selected as research subjects.They were randomly divided into experimental and control groups.The experimental group received the combined PBL-TBL teaching method,whereas the control group received the traditional teaching.The teaching effect was evaluated based on student satisfaction and academic performance.Results:The student satisfaction in the experimental group was higher than that of the control group(P<0.05).Subjective scoring for academic performance by instructors was higher in the experimental group than in the control group(P<0.05).Conclusion:The PBL and TBL combination had a significant effect when applied in plastic and reconstructive surgery clinical practice.展开更多
To elucidate the mechanisms of regulating the microstructure uniformity in 7050 aluminum forgings through surface cumulative plastic deformation(SCPD),the microstructure under different solution treatments was investi...To elucidate the mechanisms of regulating the microstructure uniformity in 7050 aluminum forgings through surface cumulative plastic deformation(SCPD),the microstructure under different solution treatments was investigated using metallographic observation(OM),electron backscatter diffraction(EBSD),transmission electron microscopy(TEM),and X-ray diffraction(XRD).The findings demonstrate that the most uniform microstructure in the forgings is achieved with a solution treatment at 470℃for 30 min.The SCPD process generates a significant number of needle-shaped precipitates,resulting in a higher dislocation density and stored energy.Solution treatments alleviate the pinning effect of second-phase particles and facilitate static recrystallization(SRX)in forgings,leading to a reduction in grain size.Additionally,mechanical testing results demonstrate 7%−13%increase in tensile strength and more uniform elongation of the forgings in different directions.展开更多
General situation of China plastics industry in 2009 was reviewed,including the output/sales and export/import of plastics products,synthetic resins,plastics processing machinery and additives.
Microplastic pollution represents a side-effect stemming from a global plastic waste mismanagement problem and includes degraded particles or mass produced plastic particles less than 5 mm in largest dimension.The sma...Microplastic pollution represents a side-effect stemming from a global plastic waste mismanagement problem and includes degraded particles or mass produced plastic particles less than 5 mm in largest dimension.The small nature of microplastics gives this area of pollution different environmental concerns than general plastic waste in the environment.The biological toxicity of particles,their internal components,and their surface level changes all present opportunities for these particles to adversely affect the environment around them.Thus,it is necessary to review the current literature surrounding this topic and identify areas where the study of microplastic can be pushed forward.Here we present current methods in studying microplastics,some of the ways by which microplastics affect the environment and attempt to shed light on how this research can continue.In addition,we review current recycling methods developing for the processing of mixed-plastic waste.These methods,including hydrothermal processing and solvent extraction,provide a unique opportunity to separate plastic waste and improve the viability of the plastics recycling industry.展开更多
The selection of carbon sources and the biosynthesis of polyhydroxybutyrate(PHB)by the Azotobacter vinelandii N-15 strain using renewable raw materials were investigated.Among the tested substrates(starch,sucrose,mola...The selection of carbon sources and the biosynthesis of polyhydroxybutyrate(PHB)by the Azotobacter vinelandii N-15 strain using renewable raw materials were investigated.Among the tested substrates(starch,sucrose,molasses,bran),molasses as the carbon source yielded the highest PHB production.The maximum polymer yield(26%of dry biomass)was achieved at a molasses concentration of 40 g/L.PHB formation was confirmed via thinlayer chromatography,gas chromatography and Fourier transform infrared spectroscopy.Composite films based on PHB,polylactic acid(PLA),and their blends were fabricated using the solvent casting.The biodegradation of these films was studied with bacteria isolated from plastic-contaminated soil.These bacteria utilized the biopolymers as their sole carbon source,with the biodegradation process lasting three months.Structural and chemical changes in the films were analyzed using FTIR spectroscopy,differential scanning calorimetry,and thermogravimetry.Among the microorganisms used to study the biodegradation of PHB,PLA,and their blends,Streptomyces sp.K2 and Streptomyces sp.K4 exhibited the highest biodegradation efficiency.PHB-containing films demonstrated significant advantages over other biodegradable polymers,as they degrade under aerobic conditions via enzymatic hydrolysis using microbial depolymerases.展开更多
Increasing production and use of various novel plastics products,a low recycling rate,and lack of effective recycling/disposal methods have resulted in an exponential growth in plastic waste accumulation in landfills ...Increasing production and use of various novel plastics products,a low recycling rate,and lack of effective recycling/disposal methods have resulted in an exponential growth in plastic waste accumulation in landfills and in the environment.To better understand the effects of plastic waste,Life Cycle Analysis(LCA)was done to compare the effects of various production and disposal methods.LCA shows the specific effects of the cradle-to-grave or cradle-to-cradle scenarios for landfill,incineration,and mechanical recycling.The analysis clearly indicates that increasing recycling of plastics can significantly save energy and eliminate harmful emissions of various carcinogens and GHGs into the environment.As recycling increases,the need for virgin-plastic production can be greatly reduced.Furthermore,the results of this study may help improve current mechanical recycling processes as well as potential future recycling methods,such as chemical recycling.Concerns about the current recycling/disposal methods for plastics have brought increasing attention to the waste accumulation problem.However,with the current COVID-19 pandemic,plastic accumulation is expected to increase significantly in the near future.A better understanding of the quantitative effects of the various disposal methods can help guide policies and future research toward effective solutions of the plastic waste problem.展开更多
This study focused on the various surface treatments of grinding,Na OH etching,HCl pickling,micro-arc oxidation and anodic oxidation to strengthen adhesive bonding joint of Aluminum(Al)substrate and Carbon Fiber Reinf...This study focused on the various surface treatments of grinding,Na OH etching,HCl pickling,micro-arc oxidation and anodic oxidation to strengthen adhesive bonding joint of Aluminum(Al)substrate and Carbon Fiber Reinforced Plastics(CFRP).Different surface conditions were created by these treatments and simple Resin Pre-Coating(RPC)technique was further used to reduce the potential void defects at the root of those micro-cavities.Carbon Nanotubes(CNTs)were guided into the etched micro-cavities to construct quasi-Z-directional fiber bridging and form the“CNT-reinforced epoxy-pins”.The surface performance testing results imply that anodic oxidation of Al substrate created relatively even and continuous channels with higher hardness and better wettability among these treatments,which could provide quasi-vertical spaces for containing epoxy adhesive or CNTs.The single lap shear test results show combined treatments of anodic oxidation and upgraded RPC with CNTs technique on Al substrate yielded the highest bonding strength of 21.8 MPa(up to 243.3% greater than base strength).The constructed through-the-thickness“epoxy-pins”or“CNT-reinforced epoxy-pins”contributed to failure modes changing from complete debonding failure of Al substrate to peeled-off shallow fiber or delamination failure of CFRP panel.The combined treatments could be utilized to manufacture high-performance Al-CFRP composites for aviation industry application.展开更多
Steady state plastic flow of the ideal plastic half-space surface by sliding elliptical cylinder is numerically calculated with account of contact friction effect. Numerical solution of the plane strain hyperbolic dif...Steady state plastic flow of the ideal plastic half-space surface by sliding elliptical cylinder is numerically calculated with account of contact friction effect. Numerical solution of the plane strain hyperbolic differential equations with unknown contact pressure distribution is treated as nonlinear vector equation for the steady state plastic flow condition. Pronounced effect of the ellipse boundary curvature on the plastic flow mode is shown. Engineering application of the computer model is surface plastic deformation technology to improve wear and fatigue resistance of metal parts.展开更多
Apart from listening to the cry of a healthy newborn,it is the declaration by the attending paediatrician in the labour room that the child is normal which brings utmost joy to parents.The global incidence of children...Apart from listening to the cry of a healthy newborn,it is the declaration by the attending paediatrician in the labour room that the child is normal which brings utmost joy to parents.The global incidence of children born with congenital anomalies has been reported to be 3%-6%with more than 90%of these occurring in low-and middle-income group countries.The exact percentages/total numbers of children requiring surgical treatment cannot be estimated for several reasons.These children are operated under several surgical disciplines,viz,paediatric-,plastic reconstructive,neuro-,cardiothoracic-,orthopaedic surgery etc.These conditions may be life-threatening,e.g.,trachea-oesophageal fistula,critical pulmonary stenosis,etc.and require immediate surgical intervention.Some,e.g.,hydrocephalus,may need intervention as soon as the patient is fit for surgery.Some,e.g.,patent ductus arteriosus need‘wait and watch’policy up to a certain age in the hope of spontaneous recovery.Another extremely important category is that of patients where the operative intervention is done based on their age.Almost all the congenital anomalies coming under care of a plastic surgeon are operated as elective surgery(many as multiple stages of correction)at appropriate ages.There are advantages and disadvantages of intervention at different ages.In this article,we present a review of optimal timings,along with reasoning,for surgery of many of the common congenital anomalies which are treated by plastic surgeons.Obstetricians,paediatricians and general practitioners/family physicians,who most often are the first ones to come across such children,must know to guide the parents appropriately and convincingly impress upon the them as to why their child should not be operated immediately and also the consequences of too soon or too late.展开更多
Objective: to analyze the application and clinical significance of early burn plastic surgery. Methods: Methods: 156 cases of burn and plastic surgery patients in my hospital who received early plastic surgery after 1...Objective: to analyze the application and clinical significance of early burn plastic surgery. Methods: Methods: 156 cases of burn and plastic surgery patients in my hospital who received early plastic surgery after 10 days were compared. The cases of two groups of patients who received early plastic surgery after 10 days were compared, and 102 cases of two groups of patients who received early plastic surgery after 10 days were compared. Results: The excellent and good rates of the short-term therapeutic effects in the experimental group after the operation reached 93.99% respectively;However, in the control group, the excellent and good rate of the recent treatment after the recent treatment reached 79.29% respectively, and the comparative difference between the two was statistically significant (P<0.05). During the long-term follow-up of the patients, no case in the experimental group may have significant scar and scar hyperplasia in the operation area, so it is required to complete the secondary operation, which is equivalent to the control group. Only 19 hands may have significant scar and scar, and need to undergo the secondary operation again. The occurrence rate has reached 13.57%. The difference between the two groups has certain data and statistical significance (P<0.05). Conclusion: For patients with severe hand burn and inflammation, early reconstructive surgery should be adopted. In principle, the necessary surgical treatment should be completed. Effective surgical treatment or ideal recovery of body function should be given accordingly, which can be popularized and applied in clinical practice.展开更多
A three dimensional rate-dependent crystal plasticity model is applied to study the influence of crystal orientation and grain boundary on the void growth and coalescence. The 3D computational model is a unit cell inc...A three dimensional rate-dependent crystal plasticity model is applied to study the influence of crystal orientation and grain boundary on the void growth and coalescence. The 3D computational model is a unit cell including one sphere void or two sphere voids. The results of three different orientations for single crystal and bicrystals are compared. It is found that crystallographic orientation has noticeable influences on the void growth directionvoid shape, and void coalescence of single crystal. The void growth rate of bicrystals depends on the crystallographic orientations and grain boundary direction.展开更多
The effects of process parameters in rapid heat cycle moulding （RHCM） on parts warpage were investigated. A vehicle-used blue-tooth front shell （consisting of ABS material） was considered as a part example manufac...The effects of process parameters in rapid heat cycle moulding （RHCM） on parts warpage were investigated. A vehicle-used blue-tooth front shell （consisting of ABS material） was considered as a part example manufactured by RHCM method. The corresponding rapid heat response mould with an innovational conformal heating/cooling channel system and a dynamic mould temperature control system based on the Jll-W-160 type precise temperature controller was proposed. During heating/cooling process, the mould was able to be heated from room temperature to 160 ~C in 6 s and then cooled to 80 ~C in 22 s. The effects of processing conditions in RHCM on part warpage were investigated based on the single factor experimental method and Taguchi theory. Results reveal that the elevated mould temperature reduces unwanted freezing during the injection stage, thus improving mouldability and enhancing part quality, whereas the overheated of mould temperature will lead to defective product. The feasible mould temperature scope in RHCM should be no higher than 140 ~C, and the efficient mould temperature scope should be around the polymer heat distortion temperature. Melt temperature as well as injection pressure effects on warpage can be divided into two stages The lower stage gives a no explicit effect on warpage whereas the higher stage leads to a quasi-linear downtrend. But others affect the warpage as a V-type fluctuation, reaching to the minimum around the heat distortion temperature. Under the same mould temperature condition, the effects of process parameters on warpage decrease according to the following order, packing time, packing pressure, melt temperature, injection pressure and cooling time, respectively.展开更多
The electroplastic（EP） tensile properties of 5A90 Al–Li alloys compared with thermal tension were investigated.The microstructural variation at different conditions was observed by SEM and TEM.The current density s...The electroplastic（EP） tensile properties of 5A90 Al–Li alloys compared with thermal tension were investigated.The microstructural variation at different conditions was observed by SEM and TEM.The current density significantly influences the elongation and the flow stress.With increasing current density,wider and deeper dimples on the fracture surfaces and less dislocation density and pile-ups in the EP tension samples were observed compared with roomtemperature and thermal tension,which indicates the plasticity improvement and flow stress reduction.The EP effect（EPE） mainly results from a comprehensive function of Joule heating and pure EPE.Among them,Joule heating effect is perhaps a dominant factor.展开更多
The bulk metal forming processes were simulated by using a one-step finite element(FE)approach based on deformation theory of plasticity,which enables rapid prediction of final workpiece configurations and stress/stra...The bulk metal forming processes were simulated by using a one-step finite element(FE)approach based on deformation theory of plasticity,which enables rapid prediction of final workpiece configurations and stress/strain distributions.This approach was implemented to minimize the approximated plastic potential energy derived from the total plastic work and the equivalent external work in static equilibrium,for incompressibly rigid-plastic materials,by FE calculation based on the extremum work principle.The one-step forward simulations of compression and rolling processes were presented as examples,and the results were compared with those obtained by classical incremental FE simulation to verify the feasibility and validity of the proposed method.展开更多
Non-degradable polymers cause serious environmental pollution problem,such as the widely-used while unrecyclable coatings which significantly affect the overall degradation performance of products.It is imperative and ...Non-degradable polymers cause serious environmental pollution problem,such as the widely-used while unrecyclable coatings which significantly affect the overall degradation performance of products.It is imperative and attractive to develop biodegradable functional coatings.Herein,we proposed a novel strategy to successfully prepare biodegradable,thermoplastic and hydrophobic coatings with high transparence and biosafety by weakening the interchain interactions between cellulose chain.The natural cellulose and cinnamic acid were as raw materials.Via reducing the degree of polymerization(DP)of cellulose and regulating the degree of substitution(DS)of cinnamate moiety,the obtained cellulose cinnamate(CC)exhibited not only the thermalflow behavior but also good biodegradability,which solves the conflict between the thermoplasticity and biodegradability in cellulose-based materials.The glass transition temperature(T_(g))and thermalflow temperature(T_(f))of the CC could be adjusted in a range of 150–200℃ and 180–210℃,respectively.The CC with DS<1.2 and DP≤100 degraded more than 60%after an enzyme treatment for 7 days,and degraded more than 80%after a composting treatment for 42 days.Furthermore,CC had no toxicity to human epidermal cells even at a high concentration(0.5 mg mL^(-1)).In addition,CC could be easily fabricated into multifunctional coating with high hydrophobicity,thermal adhesion and high transparence.Therefore,after combining with cellophane and paperboard,CC coating with low DP and DS could be used to prepare fully-biodegradable heat-sealing packaging,art paper,paper cups,paper straws and food packaging boxes.展开更多
This study explores how parametric uncertainties in the production affect failure tensile loads of reinforced thermoplastic pipes(RTPs)under combined loading conditions.The stress distributions in RTPs are examined wi...This study explores how parametric uncertainties in the production affect failure tensile loads of reinforced thermoplastic pipes(RTPs)under combined loading conditions.The stress distributions in RTPs are examined with three-dimensional(3D)elasticity theory,and the analytical micromechanics of composites are evaluated.To evaluate the failure mechanisms for RTPs,3D Hashin–Yeh failure criteria are combined with the damage evolution model to establish a progressive failure model.The theoretical model has been validated through numerical simulations and axial tensile tests data.To analyze how randomness of relevant parameters affects the first-ply failure(FPF)tensile load and final failure(FF)tensile load in RTPs,many samples are produced with the Monte–Carlo approach.The stochastic analysis results are statistically evaluated through the Weibull probability density distribution function.For the randomness of production parameters,the failure tensile load of RTPs fluctuates near the mean value.As the ply number at the reinforced layer increases,the dispersion of failure tensile load increases,with a high probability that the FPF tensile load of RTPs is lower than the mean value.展开更多
文摘Background: Missions organized by international societies and humanitarian organizations play a significant role in saving many patients’ lives and improving their quality of life, despite the surrounding frustrating conditions. Methods: A team of plastic surgery volunteers was sent to Yemen by the KSHARC. Results: A successful mission was performed on 62 patients who underwent surgery, with more than 900 patients examined and receiving appropriate medications. Conclusion: Missions in disaster-affected areas are of great importance. The role of missions and humanitarian organizations should be empowered.
文摘BACKGROUND As artificial intelligence(AI)continues to expand across medical specialties,its application in medical imaging within plastic and reconstructive surgery(PRS)remains limited in the literature.Imaging plays a critical role in surgical planning,intraoperative decision-making,and postoperative monitoring in PRS,presenting an opportunity for AI to enhance clinical outcomes.AIM To evaluate the current applications of AI in medical imaging for plastic surgery,with a focus on its use in preoperative planning,intraoperative guidance,and postoperative monitoring.METHODS A literature search was conducted using MEDLINE,EMBASE,ScienceDirect,and OVID up to February 2025.Studies were included based on relevance to AI use in plastic surgery imaging.Extracted data included AI modality,surgical context,outcomes,and limitations.The search followed PRISMA guidelines and was registered with PROSPERO(CRD420251008741).RESULTS AI tools have improved preoperative planning through three-dimensional vascular mapping,augmented reality,and thermographic imaging.Intraoperatively,AI-enabled navigation and robotic systems have increased surgical precision.Postoperative AI applications,including deep learning algorithms and sensorbased monitoring,support early complication detection and wound healing assessment.However,persistent barriers include data variability,model generalizability,surgeon unfamiliarity,and lack of regulatory standards.CONCLUSION AI-driven imaging technologies show promise in enhancing decision-making and outcomes in PRS.To ensure safe clinical integration,future efforts must focus on structured validation,standardization,and ethical oversight.
文摘Objective:To explore the clinical application effect of autologous fat granule transplantation in facial depression plastic surgery.Methods:A total of 98 patients with facial depression admitted to the plastic surgery department of our hospital from January 2021 to December 2023 were selected and divided into observation group(49 cases)and control group(49 cases)according to the random number table method.The observation group was treated with autologous fat granule transplantation,while the control group was treated with hyaluronic acid filling.The total effective rate of treatment,incidence of postoperative complications,improvement indicators of facial morphology(depth of depression,symmetry),and effect maintenance rate after 6 months of follow-up were compared between the two groups.Results:The total effective rate of treatment in the observation group was 93.88%(46/49),which was significantly higher than that in the control group(79.59%,39/49)(P<0.05).The incidence of postoperative complications in the observation group was 6.12%(3/49),which was lower than that in the control group(20.41%,10/49)(P<0.05).One month after surgery,the depth of depression(1.23±0.31 mm)and symmetry(1.02±0.15 points)in the observation group were better than those in the control group(P<0.05).After 6 months of follow-up,the effect maintenance rate in the observation group was 89.80%(44/49),which was significantly higher than that in the control group(67.35%,33/49)(P<0.05).Conclusion:Autologous fat granule transplantation for the treatment of facial depression can significantly improve facial morphology,enhance treatment effect and patient satisfaction,reduce the incidence of complications,and maintain a more durable effect.It is a clinically preferred facial depression plastic surgery solution.
基金supported by grants from the National Natural Science Foundation of China(grant nos.82472554 and 82202449)the Fund for Excellent Young Scholars of Shanghai Ninth People’s Hospital,Shanghai Jiao Tong University School of Medicine(grant no.JYYQ006).
文摘Background:This study explored the value of integrating problem-based learning(PBL)and team-based learning(TBL)methods into plastic and reconstructive surgery clinical practice.By addressing the challenges faced in traditional teachings,this study aimed to enhance educational outcomes and prepare students for real-world surgical scenarios,thereby improving patient care in this specialized field.Methods:Fifty undergraduate students majoring in clinical medicine at the Shanghai Jiao Tong University School of Medicine were selected as research subjects.They were randomly divided into experimental and control groups.The experimental group received the combined PBL-TBL teaching method,whereas the control group received the traditional teaching.The teaching effect was evaluated based on student satisfaction and academic performance.Results:The student satisfaction in the experimental group was higher than that of the control group(P<0.05).Subjective scoring for academic performance by instructors was higher in the experimental group than in the control group(P<0.05).Conclusion:The PBL and TBL combination had a significant effect when applied in plastic and reconstructive surgery clinical practice.
基金supported by the Natural Science Foundation of Hebei Province,China(Nos.E2019203075,E2021203059)the National Natural Science Foundation of China(No.52171018)+1 种基金Top Young Talents Project of the Education Department of Hebei Province,China(No.BJ2019001)the Open Research Fund of State Key Laboratory of Precision Manufacturing for Extreme Service Performance,Central South University,China(No.Kfkt2023-09).
文摘To elucidate the mechanisms of regulating the microstructure uniformity in 7050 aluminum forgings through surface cumulative plastic deformation(SCPD),the microstructure under different solution treatments was investigated using metallographic observation(OM),electron backscatter diffraction(EBSD),transmission electron microscopy(TEM),and X-ray diffraction(XRD).The findings demonstrate that the most uniform microstructure in the forgings is achieved with a solution treatment at 470℃for 30 min.The SCPD process generates a significant number of needle-shaped precipitates,resulting in a higher dislocation density and stored energy.Solution treatments alleviate the pinning effect of second-phase particles and facilitate static recrystallization(SRX)in forgings,leading to a reduction in grain size.Additionally,mechanical testing results demonstrate 7%−13%increase in tensile strength and more uniform elongation of the forgings in different directions.
文摘General situation of China plastics industry in 2009 was reviewed,including the output/sales and export/import of plastics products,synthetic resins,plastics processing machinery and additives.
文摘Microplastic pollution represents a side-effect stemming from a global plastic waste mismanagement problem and includes degraded particles or mass produced plastic particles less than 5 mm in largest dimension.The small nature of microplastics gives this area of pollution different environmental concerns than general plastic waste in the environment.The biological toxicity of particles,their internal components,and their surface level changes all present opportunities for these particles to adversely affect the environment around them.Thus,it is necessary to review the current literature surrounding this topic and identify areas where the study of microplastic can be pushed forward.Here we present current methods in studying microplastics,some of the ways by which microplastics affect the environment and attempt to shed light on how this research can continue.In addition,we review current recycling methods developing for the processing of mixed-plastic waste.These methods,including hydrothermal processing and solvent extraction,provide a unique opportunity to separate plastic waste and improve the viability of the plastics recycling industry.
基金financial support of this paper by the Ministry of Education and Science of Ukraine under grant(Biotherm/0124U000789).
文摘The selection of carbon sources and the biosynthesis of polyhydroxybutyrate(PHB)by the Azotobacter vinelandii N-15 strain using renewable raw materials were investigated.Among the tested substrates(starch,sucrose,molasses,bran),molasses as the carbon source yielded the highest PHB production.The maximum polymer yield(26%of dry biomass)was achieved at a molasses concentration of 40 g/L.PHB formation was confirmed via thinlayer chromatography,gas chromatography and Fourier transform infrared spectroscopy.Composite films based on PHB,polylactic acid(PLA),and their blends were fabricated using the solvent casting.The biodegradation of these films was studied with bacteria isolated from plastic-contaminated soil.These bacteria utilized the biopolymers as their sole carbon source,with the biodegradation process lasting three months.Structural and chemical changes in the films were analyzed using FTIR spectroscopy,differential scanning calorimetry,and thermogravimetry.Among the microorganisms used to study the biodegradation of PHB,PLA,and their blends,Streptomyces sp.K2 and Streptomyces sp.K4 exhibited the highest biodegradation efficiency.PHB-containing films demonstrated significant advantages over other biodegradable polymers,as they degrade under aerobic conditions via enzymatic hydrolysis using microbial depolymerases.
基金The authors would like to thank the University of Massachusetts Lowell for providing start-up funds.N.F.andW.-T.C.would like to thank the financial support by the U.S.Department of Energy’s Office of Energy Efficiency and Renewable Energy(EERE)under the Advanced Manufacturing Office Award No.DE-EE0007897。
文摘Increasing production and use of various novel plastics products,a low recycling rate,and lack of effective recycling/disposal methods have resulted in an exponential growth in plastic waste accumulation in landfills and in the environment.To better understand the effects of plastic waste,Life Cycle Analysis(LCA)was done to compare the effects of various production and disposal methods.LCA shows the specific effects of the cradle-to-grave or cradle-to-cradle scenarios for landfill,incineration,and mechanical recycling.The analysis clearly indicates that increasing recycling of plastics can significantly save energy and eliminate harmful emissions of various carcinogens and GHGs into the environment.As recycling increases,the need for virgin-plastic production can be greatly reduced.Furthermore,the results of this study may help improve current mechanical recycling processes as well as potential future recycling methods,such as chemical recycling.Concerns about the current recycling/disposal methods for plastics have brought increasing attention to the waste accumulation problem.However,with the current COVID-19 pandemic,plastic accumulation is expected to increase significantly in the near future.A better understanding of the quantitative effects of the various disposal methods can help guide policies and future research toward effective solutions of the plastic waste problem.
基金supported financially by the National Natural Science Foundations of China(No.52102115)the Natural Science Foundation of Sichuan Province,China(No.2025HJRC0019)+1 种基金the Basalt Fiber and Composite Key Laboratory of Sichuan Province,China(No.XXKFJJ202308)Shock and Vibration of Engineering Materials and Structures Key Lab of Sichuan Province,China(No.23kfgk06)。
文摘This study focused on the various surface treatments of grinding,Na OH etching,HCl pickling,micro-arc oxidation and anodic oxidation to strengthen adhesive bonding joint of Aluminum(Al)substrate and Carbon Fiber Reinforced Plastics(CFRP).Different surface conditions were created by these treatments and simple Resin Pre-Coating(RPC)technique was further used to reduce the potential void defects at the root of those micro-cavities.Carbon Nanotubes(CNTs)were guided into the etched micro-cavities to construct quasi-Z-directional fiber bridging and form the“CNT-reinforced epoxy-pins”.The surface performance testing results imply that anodic oxidation of Al substrate created relatively even and continuous channels with higher hardness and better wettability among these treatments,which could provide quasi-vertical spaces for containing epoxy adhesive or CNTs.The single lap shear test results show combined treatments of anodic oxidation and upgraded RPC with CNTs technique on Al substrate yielded the highest bonding strength of 21.8 MPa(up to 243.3% greater than base strength).The constructed through-the-thickness“epoxy-pins”or“CNT-reinforced epoxy-pins”contributed to failure modes changing from complete debonding failure of Al substrate to peeled-off shallow fiber or delamination failure of CFRP panel.The combined treatments could be utilized to manufacture high-performance Al-CFRP composites for aviation industry application.
文摘Steady state plastic flow of the ideal plastic half-space surface by sliding elliptical cylinder is numerically calculated with account of contact friction effect. Numerical solution of the plane strain hyperbolic differential equations with unknown contact pressure distribution is treated as nonlinear vector equation for the steady state plastic flow condition. Pronounced effect of the ellipse boundary curvature on the plastic flow mode is shown. Engineering application of the computer model is surface plastic deformation technology to improve wear and fatigue resistance of metal parts.
文摘Apart from listening to the cry of a healthy newborn,it is the declaration by the attending paediatrician in the labour room that the child is normal which brings utmost joy to parents.The global incidence of children born with congenital anomalies has been reported to be 3%-6%with more than 90%of these occurring in low-and middle-income group countries.The exact percentages/total numbers of children requiring surgical treatment cannot be estimated for several reasons.These children are operated under several surgical disciplines,viz,paediatric-,plastic reconstructive,neuro-,cardiothoracic-,orthopaedic surgery etc.These conditions may be life-threatening,e.g.,trachea-oesophageal fistula,critical pulmonary stenosis,etc.and require immediate surgical intervention.Some,e.g.,hydrocephalus,may need intervention as soon as the patient is fit for surgery.Some,e.g.,patent ductus arteriosus need‘wait and watch’policy up to a certain age in the hope of spontaneous recovery.Another extremely important category is that of patients where the operative intervention is done based on their age.Almost all the congenital anomalies coming under care of a plastic surgeon are operated as elective surgery(many as multiple stages of correction)at appropriate ages.There are advantages and disadvantages of intervention at different ages.In this article,we present a review of optimal timings,along with reasoning,for surgery of many of the common congenital anomalies which are treated by plastic surgeons.Obstetricians,paediatricians and general practitioners/family physicians,who most often are the first ones to come across such children,must know to guide the parents appropriately and convincingly impress upon the them as to why their child should not be operated immediately and also the consequences of too soon or too late.
文摘Objective: to analyze the application and clinical significance of early burn plastic surgery. Methods: Methods: 156 cases of burn and plastic surgery patients in my hospital who received early plastic surgery after 10 days were compared. The cases of two groups of patients who received early plastic surgery after 10 days were compared, and 102 cases of two groups of patients who received early plastic surgery after 10 days were compared. Results: The excellent and good rates of the short-term therapeutic effects in the experimental group after the operation reached 93.99% respectively;However, in the control group, the excellent and good rate of the recent treatment after the recent treatment reached 79.29% respectively, and the comparative difference between the two was statistically significant (P<0.05). During the long-term follow-up of the patients, no case in the experimental group may have significant scar and scar hyperplasia in the operation area, so it is required to complete the secondary operation, which is equivalent to the control group. Only 19 hands may have significant scar and scar, and need to undergo the secondary operation again. The occurrence rate has reached 13.57%. The difference between the two groups has certain data and statistical significance (P<0.05). Conclusion: For patients with severe hand burn and inflammation, early reconstructive surgery should be adopted. In principle, the necessary surgical treatment should be completed. Effective surgical treatment or ideal recovery of body function should be given accordingly, which can be popularized and applied in clinical practice.
基金supported by National Natural Science Foundation of China(No.50575143)the Research Fund for the Doctoral Program of Higher Educa-tion (No.20040248005)
文摘A three dimensional rate-dependent crystal plasticity model is applied to study the influence of crystal orientation and grain boundary on the void growth and coalescence. The 3D computational model is a unit cell including one sphere void or two sphere voids. The results of three different orientations for single crystal and bicrystals are compared. It is found that crystallographic orientation has noticeable influences on the void growth directionvoid shape, and void coalescence of single crystal. The void growth rate of bicrystals depends on the crystallographic orientations and grain boundary direction.
基金Project(20122BAB206014)supported by National Natural Science Foundation of ChinaProject(51365038)supported by the Natural Science Foundation of Jiangxi Province,ChinaProject(GJJ13068)supported by the Science and Technology Program of Educational Committee of Jiangxi Province,China
文摘The effects of process parameters in rapid heat cycle moulding （RHCM） on parts warpage were investigated. A vehicle-used blue-tooth front shell （consisting of ABS material） was considered as a part example manufactured by RHCM method. The corresponding rapid heat response mould with an innovational conformal heating/cooling channel system and a dynamic mould temperature control system based on the Jll-W-160 type precise temperature controller was proposed. During heating/cooling process, the mould was able to be heated from room temperature to 160 ~C in 6 s and then cooled to 80 ~C in 22 s. The effects of processing conditions in RHCM on part warpage were investigated based on the single factor experimental method and Taguchi theory. Results reveal that the elevated mould temperature reduces unwanted freezing during the injection stage, thus improving mouldability and enhancing part quality, whereas the overheated of mould temperature will lead to defective product. The feasible mould temperature scope in RHCM should be no higher than 140 ~C, and the efficient mould temperature scope should be around the polymer heat distortion temperature. Melt temperature as well as injection pressure effects on warpage can be divided into two stages The lower stage gives a no explicit effect on warpage whereas the higher stage leads to a quasi-linear downtrend. But others affect the warpage as a V-type fluctuation, reaching to the minimum around the heat distortion temperature. Under the same mould temperature condition, the effects of process parameters on warpage decrease according to the following order, packing time, packing pressure, melt temperature, injection pressure and cooling time, respectively.
基金financially supported by the National Natural Science Foundation of China (No.51105248)
文摘The electroplastic（EP） tensile properties of 5A90 Al–Li alloys compared with thermal tension were investigated.The microstructural variation at different conditions was observed by SEM and TEM.The current density significantly influences the elongation and the flow stress.With increasing current density,wider and deeper dimples on the fracture surfaces and less dislocation density and pile-ups in the EP tension samples were observed compared with roomtemperature and thermal tension,which indicates the plasticity improvement and flow stress reduction.The EP effect（EPE） mainly results from a comprehensive function of Joule heating and pure EPE.Among them,Joule heating effect is perhaps a dominant factor.
基金Project(50575143)supported by the National Natural Science Foundation of ChinaProject(20040248005)supported by the Specialized Research Fund for the Doctoral Program of Higher Education of China
文摘The bulk metal forming processes were simulated by using a one-step finite element(FE)approach based on deformation theory of plasticity,which enables rapid prediction of final workpiece configurations and stress/strain distributions.This approach was implemented to minimize the approximated plastic potential energy derived from the total plastic work and the equivalent external work in static equilibrium,for incompressibly rigid-plastic materials,by FE calculation based on the extremum work principle.The one-step forward simulations of compression and rolling processes were presented as examples,and the results were compared with those obtained by classical incremental FE simulation to verify the feasibility and validity of the proposed method.
基金supported by the National Natural Science Foundation of China(No.52173292)the National Key Research and Development Project of China(No.2020YFC1910303)the Youth Innovation Promotion Association CAS(No.2018040).
文摘Non-degradable polymers cause serious environmental pollution problem,such as the widely-used while unrecyclable coatings which significantly affect the overall degradation performance of products.It is imperative and attractive to develop biodegradable functional coatings.Herein,we proposed a novel strategy to successfully prepare biodegradable,thermoplastic and hydrophobic coatings with high transparence and biosafety by weakening the interchain interactions between cellulose chain.The natural cellulose and cinnamic acid were as raw materials.Via reducing the degree of polymerization(DP)of cellulose and regulating the degree of substitution(DS)of cinnamate moiety,the obtained cellulose cinnamate(CC)exhibited not only the thermalflow behavior but also good biodegradability,which solves the conflict between the thermoplasticity and biodegradability in cellulose-based materials.The glass transition temperature(T_(g))and thermalflow temperature(T_(f))of the CC could be adjusted in a range of 150–200℃ and 180–210℃,respectively.The CC with DS<1.2 and DP≤100 degraded more than 60%after an enzyme treatment for 7 days,and degraded more than 80%after a composting treatment for 42 days.Furthermore,CC had no toxicity to human epidermal cells even at a high concentration(0.5 mg mL^(-1)).In addition,CC could be easily fabricated into multifunctional coating with high hydrophobicity,thermal adhesion and high transparence.Therefore,after combining with cellophane and paperboard,CC coating with low DP and DS could be used to prepare fully-biodegradable heat-sealing packaging,art paper,paper cups,paper straws and food packaging boxes.
基金financially supported by the National Natural Science Foundation of China(Grant No.U2006226]the National Key Research and Development Program of China(Grant No.2016YFC0303800)。
文摘This study explores how parametric uncertainties in the production affect failure tensile loads of reinforced thermoplastic pipes(RTPs)under combined loading conditions.The stress distributions in RTPs are examined with three-dimensional(3D)elasticity theory,and the analytical micromechanics of composites are evaluated.To evaluate the failure mechanisms for RTPs,3D Hashin–Yeh failure criteria are combined with the damage evolution model to establish a progressive failure model.The theoretical model has been validated through numerical simulations and axial tensile tests data.To analyze how randomness of relevant parameters affects the first-ply failure(FPF)tensile load and final failure(FF)tensile load in RTPs,many samples are produced with the Monte–Carlo approach.The stochastic analysis results are statistically evaluated through the Weibull probability density distribution function.For the randomness of production parameters,the failure tensile load of RTPs fluctuates near the mean value.As the ply number at the reinforced layer increases,the dispersion of failure tensile load increases,with a high probability that the FPF tensile load of RTPs is lower than the mean value.
