Recycling of junks is positive for the environmental protection.Along with the proposal of three-child policy,purchase volume of milk powder surely will experience a drastic growth,and the milk powder spoon as an affi...Recycling of junks is positive for the environmental protection.Along with the proposal of three-child policy,purchase volume of milk powder surely will experience a drastic growth,and the milk powder spoon as an affiliated product will win the attention of parents.Against the background of consumption upgrading,consumers have had higher requirements on the humanization and safety design of products.Most of milk powder spoons on the market are plastic,and the disposal of waste milk powder spoon has gradually become a burden for the environment.Based on the environment-friendly and developmental concept,and also the characteristics of infant development,this paper proposed the“in-one”design,applied color and tactile designs into the milk powder design,chose food grade silicone to make the milk powder spoon not only a spoon but also a baby teether toy,so as to expand the service life and functions of the product,meet the requirements of saving energy,protecting environment and developing circular economy,which also to some extent reduces the burden on environment brought by plastics,improves the efficiency of junk recycling,and meet the individualized needs of consumers.展开更多
How nutritional conditions during early development affect an organism’s phenotype at adulthood is still poorly understood despite a plethora of research on developmental plasticity.The"environmental matching&qu...How nutritional conditions during early development affect an organism’s phenotype at adulthood is still poorly understood despite a plethora of research on developmental plasticity.The"environmental matching"hypothesis predicts that individuals will have high fitness providing that their adult environment"matches"what they experienced during development.In contrast,the"silver spoon"hypothesis predicts that individuals who obtain better developmental resources will be generally superior.Here we tested these two hypotheses and examined the underlying hormonal mechanisms by manipulating the early dietary protein content of African clawed frogs(Xenopus laevis)for a year with a 2×2 factorial experimental design.We found that only a lowprotein food during development enhanced the vocal competition ability of male X.laevis,and that vocal dominance was associated with higher cortisol levels but not related with testosterone content.These results were not congruent with the"environmental matching"hypothesis or with the"silver spoon"hypothesis,suggesting the behavioral plasticity during development is more complex than our expectation in amphibians.展开更多
In this study, it is attempted to give an insight into the injection processability of three self-prepared polymers from A to Z. This work presents material analysis, injection molding simulation, design of ex- perime...In this study, it is attempted to give an insight into the injection processability of three self-prepared polymers from A to Z. This work presents material analysis, injection molding simulation, design of ex- periments alongside considering all interaction effects of controlling parameters carefully for green biodegradable polymeric systems, including polylactic acid （PLA）, polylactic acid-thermoplastic poly- urethane （PLA-TPU） and polylactic acid-thermoplastic starch （PLA-TPS）. The experiments were carried out using injection molding simulation software Autodesk Moldflov~~ in order to minimize warpage and volumetric shrinkage for each of the mentioned systems. The analysis was conducted by changing five significant processing parameters, including coolant temperature, packing time, packing pressure, mold temperature and melt temperature. Taguchi＇s [.27 （35） orthogonal array was selected as an efficient method for design of simulations in order to consider the interaction effects of the parameters and reduce spu- rious simulations. Meanwhile, artificial neural network （ANN） was also used for pattern recognition and optimization through modifying the processing conditions. The Taguchi coupled analysis of variance （ANOVA） and ANN analysis resulted in definition of optimum levels for each factor by two completely different methods. According to the results, melting temperature, coolant temperature and packing time had significant influence on the shrinkage and warpage. The ANN optimal level selection for minimiza- tion of shrinkage and/or warpage is in good agreement with ANOVA optimal level selection results. This investigation indicates that PLA-TPU compound exhibits the highest resistance to warpage and shrink- age defects compared to the other studied compounds.展开更多
基金Sponsored by 2022 Teaching Reform Project of Lingnan Normal University(000302201830)2022 Model Course of Lingnan Normal University(LingShiJiaoWu(2014)No.125)2023 Undergraduate Students’Innovation and entrepreneurship Planning of Lingnan Normal University(X202310579049X).
文摘Recycling of junks is positive for the environmental protection.Along with the proposal of three-child policy,purchase volume of milk powder surely will experience a drastic growth,and the milk powder spoon as an affiliated product will win the attention of parents.Against the background of consumption upgrading,consumers have had higher requirements on the humanization and safety design of products.Most of milk powder spoons on the market are plastic,and the disposal of waste milk powder spoon has gradually become a burden for the environment.Based on the environment-friendly and developmental concept,and also the characteristics of infant development,this paper proposed the“in-one”design,applied color and tactile designs into the milk powder design,chose food grade silicone to make the milk powder spoon not only a spoon but also a baby teether toy,so as to expand the service life and functions of the product,meet the requirements of saving energy,protecting environment and developing circular economy,which also to some extent reduces the burden on environment brought by plastics,improves the efficiency of junk recycling,and meet the individualized needs of consumers.
基金financially supported by grants for the National Natural Science Foundation of China(31370431)to JFCthe Sichuan Provincial Science and Technology Department(2018JY0617)to JFCthe Biodiversity Survey and Assessment Project of the Ministry of Ecology and Environment,China(2019HJ2096001006)to JFC。
文摘How nutritional conditions during early development affect an organism’s phenotype at adulthood is still poorly understood despite a plethora of research on developmental plasticity.The"environmental matching"hypothesis predicts that individuals will have high fitness providing that their adult environment"matches"what they experienced during development.In contrast,the"silver spoon"hypothesis predicts that individuals who obtain better developmental resources will be generally superior.Here we tested these two hypotheses and examined the underlying hormonal mechanisms by manipulating the early dietary protein content of African clawed frogs(Xenopus laevis)for a year with a 2×2 factorial experimental design.We found that only a lowprotein food during development enhanced the vocal competition ability of male X.laevis,and that vocal dominance was associated with higher cortisol levels but not related with testosterone content.These results were not congruent with the"environmental matching"hypothesis or with the"silver spoon"hypothesis,suggesting the behavioral plasticity during development is more complex than our expectation in amphibians.
文摘In this study, it is attempted to give an insight into the injection processability of three self-prepared polymers from A to Z. This work presents material analysis, injection molding simulation, design of ex- periments alongside considering all interaction effects of controlling parameters carefully for green biodegradable polymeric systems, including polylactic acid （PLA）, polylactic acid-thermoplastic poly- urethane （PLA-TPU） and polylactic acid-thermoplastic starch （PLA-TPS）. The experiments were carried out using injection molding simulation software Autodesk Moldflov~~ in order to minimize warpage and volumetric shrinkage for each of the mentioned systems. The analysis was conducted by changing five significant processing parameters, including coolant temperature, packing time, packing pressure, mold temperature and melt temperature. Taguchi＇s [.27 （35） orthogonal array was selected as an efficient method for design of simulations in order to consider the interaction effects of the parameters and reduce spu- rious simulations. Meanwhile, artificial neural network （ANN） was also used for pattern recognition and optimization through modifying the processing conditions. The Taguchi coupled analysis of variance （ANOVA） and ANN analysis resulted in definition of optimum levels for each factor by two completely different methods. According to the results, melting temperature, coolant temperature and packing time had significant influence on the shrinkage and warpage. The ANN optimal level selection for minimiza- tion of shrinkage and/or warpage is in good agreement with ANOVA optimal level selection results. This investigation indicates that PLA-TPU compound exhibits the highest resistance to warpage and shrink- age defects compared to the other studied compounds.
