Dramatically increasing waste polyurethane rigid foam(WPRF)draws the attention of the world.A mixture of ethylene glycol(EG)and diethylene glycol(DEG)is used as glycolysis agents.WPRF was subjected to alcoholysis usin...Dramatically increasing waste polyurethane rigid foam(WPRF)draws the attention of the world.A mixture of ethylene glycol(EG)and diethylene glycol(DEG)is used as glycolysis agents.WPRF was subjected to alcoholysis using different catalysts which are titanium ethylene glycol and potassium hydroxide to obtain recycled polyol,respectively.The effect of a different catalyst on the viscosity and hydroxyl value of recycled polyol is discussed.The regenerated polyurethane(RPU)is performed using the recycled polyol.Infrared spectrum,compressive strength,apparent density,water absorption,scanning electron microscope,and thermogravimetric analysis are carried out to investigate the effect of WPRF degradation using different catalysts.The results show that titanium glycol is more efficient than potassium hydroxide in almost all conditions.The viscosity of the recycled polyol is relatively low,and the hydroxyl value meets the requirements of industrial use.When the titanium glycol titanium addition amount is 0.05%,the prepared RPU has a compressive strength of 0.24 MPa,an apparent density of 41.75 kg/m^(3),and a good foam structure.Besides,the water absorption rate of the RPU under the two catalytic systems is not much different,and the thermal stability is good.The recycled polyol can generally partially replace traditional polyols to prepare polyurethane rigid foams with good comprehensive properties.展开更多
We studied the influence of doctor-patient communication skills training on brain functional architecture using resting-state functional MRI（rs-fMRI） with a regional homogeneity（ReHo） method. Ten medical students ...We studied the influence of doctor-patient communication skills training on brain functional architecture using resting-state functional MRI（rs-fMRI） with a regional homogeneity（ReHo） method. Ten medical students participated in the study. A 1-year long doctor-patient communication skills training program was conducted. RsfMRI data were collected at baseline, one month and one year after training. There was a significant increase in the communication skills test average scores between baseline and 1-month duration of training（P〈0.001）. After one month of communication skills training, medical students had decreased ReHo in the right superior temporal gyrus compared with the baseline. After one year of communication skills training, students had increased ReHo in multiple regions and decreased ReHo in several regions（P 〈0.05, Alphasim corrected）. The change of ReHo values in the superior temporal gyrus negatively correlated with the change of communication skills scale score between one month after communication skills training and baseline（r=-0.734, P= 0.036）. The training program we used can be an effective approach of improving doctor-patient communication skills, and the training resulted in functional plasticity of the brain’s architecture toward optimizing locally functional organization.展开更多
A bi-component alcoholysis agent containing propylene glycol(PG)and ethanolamine(ETA)was used to catalyst the degradation of the waste polyurethane rigid foam.The oligomer polyols obtained through degradation were use...A bi-component alcoholysis agent containing propylene glycol(PG)and ethanolamine(ETA)was used to catalyst the degradation of the waste polyurethane rigid foam.The oligomer polyols obtained through degradation were used as raw materials to produce recycled polyurethane rigid foam composites with lignin as reinforcing filler.The effect of alcoholysis mass ratio on degradation was investigated by analyzing the viscosity,hydroxyl content and chemical structure of the degradation products.The effect of lignin addition on the properties of regenerated polyurethane rigid foam were investigated by analyzing water absorption rate,compressive strength,porosity,thermal stability,thermal conductivity coefficient,morphology and thermal stability of the recycled polyurethane rigid foam.Results show that different mass ration of PG to ETA significantly affects the degradation of waste polyurethane rigid foam.Besides,only with the addition of appropriate amount of lignin,the regenerated polyurethane rigid foam composites can meet the Chinese national standard“rigid polyurethane foam for building thermal insulation”(GB/T21558-2008).At this point,the composite is with good mechanical and thermal prperties,including high compressive strength,excellent thermal insulation performance,complete cell morphology and good thermal stability.展开更多
To the Editor:The coronavirus disease 2019(COVID-19)pandemic has caused a significant global health crisis,led to staggering mortality rates,and imposed a substantial economic burden.[1]Pneumonia is the leading cause ...To the Editor:The coronavirus disease 2019(COVID-19)pandemic has caused a significant global health crisis,led to staggering mortality rates,and imposed a substantial economic burden.[1]Pneumonia is the leading cause of mortality in patients with COVID-19.During outbreak peaks,the surge in patients severely strained healthcare systems,highlighting the need for rapid and cost-effective screening methods.Although chest X-ray(CXR)is affordable and convenient,its low sensitivity limits its effectiveness for detecting lung abnormalities.Computed tomography(CT)is considered the gold standard for diagnosing pneumonia,including COVID-19 pneumonia,but it exposes patients to high doses of radiation(3-7 mSv)far exceeding the annual threshold of 1 mSv recommended by the World Health Organization.Even low-dose CT delivers an average effective dose of 1.6 mSv,adding to the patient’s radiation burden.展开更多
基金the 2019 Graduate Student Innovative Research Project of Qiqihar University Heilongjiang Province,China(YJSCX2019063)Qiqihar Science and Technology Bureau Project(GYGG-201902)Heilongjiang Provincial Department of Education Project(135409301).
文摘Dramatically increasing waste polyurethane rigid foam(WPRF)draws the attention of the world.A mixture of ethylene glycol(EG)and diethylene glycol(DEG)is used as glycolysis agents.WPRF was subjected to alcoholysis using different catalysts which are titanium ethylene glycol and potassium hydroxide to obtain recycled polyol,respectively.The effect of a different catalyst on the viscosity and hydroxyl value of recycled polyol is discussed.The regenerated polyurethane(RPU)is performed using the recycled polyol.Infrared spectrum,compressive strength,apparent density,water absorption,scanning electron microscope,and thermogravimetric analysis are carried out to investigate the effect of WPRF degradation using different catalysts.The results show that titanium glycol is more efficient than potassium hydroxide in almost all conditions.The viscosity of the recycled polyol is relatively low,and the hydroxyl value meets the requirements of industrial use.When the titanium glycol titanium addition amount is 0.05%,the prepared RPU has a compressive strength of 0.24 MPa,an apparent density of 41.75 kg/m^(3),and a good foam structure.Besides,the water absorption rate of the RPU under the two catalytic systems is not much different,and the thermal stability is good.The recycled polyol can generally partially replace traditional polyols to prepare polyurethane rigid foams with good comprehensive properties.
文摘We studied the influence of doctor-patient communication skills training on brain functional architecture using resting-state functional MRI（rs-fMRI） with a regional homogeneity（ReHo） method. Ten medical students participated in the study. A 1-year long doctor-patient communication skills training program was conducted. RsfMRI data were collected at baseline, one month and one year after training. There was a significant increase in the communication skills test average scores between baseline and 1-month duration of training（P〈0.001）. After one month of communication skills training, medical students had decreased ReHo in the right superior temporal gyrus compared with the baseline. After one year of communication skills training, students had increased ReHo in multiple regions and decreased ReHo in several regions（P 〈0.05, Alphasim corrected）. The change of ReHo values in the superior temporal gyrus negatively correlated with the change of communication skills scale score between one month after communication skills training and baseline（r=-0.734, P= 0.036）. The training program we used can be an effective approach of improving doctor-patient communication skills, and the training resulted in functional plasticity of the brain’s architecture toward optimizing locally functional organization.
文摘A bi-component alcoholysis agent containing propylene glycol(PG)and ethanolamine(ETA)was used to catalyst the degradation of the waste polyurethane rigid foam.The oligomer polyols obtained through degradation were used as raw materials to produce recycled polyurethane rigid foam composites with lignin as reinforcing filler.The effect of alcoholysis mass ratio on degradation was investigated by analyzing the viscosity,hydroxyl content and chemical structure of the degradation products.The effect of lignin addition on the properties of regenerated polyurethane rigid foam were investigated by analyzing water absorption rate,compressive strength,porosity,thermal stability,thermal conductivity coefficient,morphology and thermal stability of the recycled polyurethane rigid foam.Results show that different mass ration of PG to ETA significantly affects the degradation of waste polyurethane rigid foam.Besides,only with the addition of appropriate amount of lignin,the regenerated polyurethane rigid foam composites can meet the Chinese national standard“rigid polyurethane foam for building thermal insulation”(GB/T21558-2008).At this point,the composite is with good mechanical and thermal prperties,including high compressive strength,excellent thermal insulation performance,complete cell morphology and good thermal stability.
基金supported by the National Natural Science Foundation of China(No.82104771)Key Program of the National Natural Science Foundation of China(No.81930001)+2 种基金Shanghai Jiao Tong University Medical-Industrial Intersection Research Fund Project(No.YG2021QN94)Open Fund of Xuzhou Medical University(No.XXKF202119)Shanghai Sixth People’s Hospital Emergency Special Project for Combating COVID-19(No.ynxg202208)
文摘To the Editor:The coronavirus disease 2019(COVID-19)pandemic has caused a significant global health crisis,led to staggering mortality rates,and imposed a substantial economic burden.[1]Pneumonia is the leading cause of mortality in patients with COVID-19.During outbreak peaks,the surge in patients severely strained healthcare systems,highlighting the need for rapid and cost-effective screening methods.Although chest X-ray(CXR)is affordable and convenient,its low sensitivity limits its effectiveness for detecting lung abnormalities.Computed tomography(CT)is considered the gold standard for diagnosing pneumonia,including COVID-19 pneumonia,but it exposes patients to high doses of radiation(3-7 mSv)far exceeding the annual threshold of 1 mSv recommended by the World Health Organization.Even low-dose CT delivers an average effective dose of 1.6 mSv,adding to the patient’s radiation burden.
