This study delves into the pivotal role of sulfur vulcanization in defining the mechanical characteristics of natural rubber(NR)latex-dipped products.Utilizing sulfur vulcanization,known for its operational simplicity...This study delves into the pivotal role of sulfur vulcanization in defining the mechanical characteristics of natural rubber(NR)latex-dipped products.Utilizing sulfur vulcanization,known for its operational simplicity and cost-effectiveness,we examine its ability to enhance product elasticity and mechanical strength through various sulfidic bond formations such as mono-,di-,and polysulfidic bonds.Different vulcanization systems and sulfur contents were evaluated for their influence on the mechanical attributes of latex films,employing three types of NR latex,namely concentrated NR(CNR),deproteinized NR(DPNR),and small rubber particle NR(SRP),each representing distinct non-rubber components(NRCs).The study utilized advanced atomic force microscopy(AFM)equipped with PeakForce Quantitative Nanomechanical Mapping(QNM)to visualize and measure Young’s modulus distribution across the film of pre-vulcanized latex.Our findings reveal that films by CNR processed using the conventional vulcanization(CV)system exhibited enhanced tensile strength and elongation at break.It even showed a lower crosslink density than those processed using the efficient vulcanization(EV)system.Interestingly,DPNR films showed a more uniform distribution of Young’s modulus,correlating well with their superior mechanical strength.In contrast,SRP films showed excessive network structure formation in the particles due to accelerated vulcanization rates,hampering subsequent post-vulcanization interparticle crosslinking in film formation and remaining more rigid.The overall results Illustrate clearly that the ultimate mechanical properties of the latex films are strongly dependent on the type of sulfidic bonds formed.This research reveals further the very intricate relationship between the vulcanization methods,sulfur content,and latex type in optimizing the mechanical performance of NR latex products.It provides valuable insights for industry practices aimed at improving the quality and performance of latex-dipped goods.展开更多
Selenium nanoparticles(SeNPs)have garnered extensive research interest and shown promising applications across diverse fields owing to their distinctive properties,including antioxidant,anticancer,and antibacterial ac...Selenium nanoparticles(SeNPs)have garnered extensive research interest and shown promising applications across diverse fields owing to their distinctive properties,including antioxidant,anticancer,and antibacterial activity(Ojeda et al.,2020;Qu et al.,2023;Zambonino et al.,2021,2023).Among the various approaches employed for SeNP synthesis,green synthesis has emerged as a noteworthy and eco-friendly methodology.Keshtmand et al.(2023)underscored the significance of green-synthesized SeNPs,presenting a compelling avenue in this domain.This innovative strategy harnesses the potential of natural resources,such as plant extracts or microorganisms,to facilitate the production of SeNPs.展开更多
Dear Editor,The COVID-19 pandemic,caused by the severe acute respiratory syndrome coronavirus 2(SARS-CoV-2),has resulted in millions of deaths worldwide.It poses significant challenges in the management of immunocompr...Dear Editor,The COVID-19 pandemic,caused by the severe acute respiratory syndrome coronavirus 2(SARS-CoV-2),has resulted in millions of deaths worldwide.It poses significant challenges in the management of immunocompromised patients,particularly people with HIV(PWH).Whether PWH are more vulnerable to COVID with more adverse outcomes has been extensively studied,but the findings are inconsistent.Many cohort studies and meta-analyses support that PWH have a higher risk of SARSCoV-2 infection and more severe COVID-19 outcomes(Bertagnolio et al.,2022;Ssentongo et al.,2021).展开更多
基金supported by Mahidol University(Fundamental Fund:fiscal year 2024 by the National Science Research and Innovation Fund(NSRF),FF-078/2567)Academy of Tropical Agricultural Sciences for Science and Technology Innovation Team of National Tropical Agricultural Science Center(No.CATASCXTD202401)the National Research Council of Thailand(NRCT)via the Royal Golden Jubilee Ph.D.Program(No.PHD/0150/2560)。
文摘This study delves into the pivotal role of sulfur vulcanization in defining the mechanical characteristics of natural rubber(NR)latex-dipped products.Utilizing sulfur vulcanization,known for its operational simplicity and cost-effectiveness,we examine its ability to enhance product elasticity and mechanical strength through various sulfidic bond formations such as mono-,di-,and polysulfidic bonds.Different vulcanization systems and sulfur contents were evaluated for their influence on the mechanical attributes of latex films,employing three types of NR latex,namely concentrated NR(CNR),deproteinized NR(DPNR),and small rubber particle NR(SRP),each representing distinct non-rubber components(NRCs).The study utilized advanced atomic force microscopy(AFM)equipped with PeakForce Quantitative Nanomechanical Mapping(QNM)to visualize and measure Young’s modulus distribution across the film of pre-vulcanized latex.Our findings reveal that films by CNR processed using the conventional vulcanization(CV)system exhibited enhanced tensile strength and elongation at break.It even showed a lower crosslink density than those processed using the efficient vulcanization(EV)system.Interestingly,DPNR films showed a more uniform distribution of Young’s modulus,correlating well with their superior mechanical strength.In contrast,SRP films showed excessive network structure formation in the particles due to accelerated vulcanization rates,hampering subsequent post-vulcanization interparticle crosslinking in film formation and remaining more rigid.The overall results Illustrate clearly that the ultimate mechanical properties of the latex films are strongly dependent on the type of sulfidic bonds formed.This research reveals further the very intricate relationship between the vulcanization methods,sulfur content,and latex type in optimizing the mechanical performance of NR latex products.It provides valuable insights for industry practices aimed at improving the quality and performance of latex-dipped goods.
基金National Natural Science Foundation of China(No.32202158)Natural Science Foundation of Jiangsu Province,China(No.BK20220703)Undergraduate Innovation&Entrepreneurship Training Program of Jiangsu Province(No.202311049168XJ),China.
文摘Selenium nanoparticles(SeNPs)have garnered extensive research interest and shown promising applications across diverse fields owing to their distinctive properties,including antioxidant,anticancer,and antibacterial activity(Ojeda et al.,2020;Qu et al.,2023;Zambonino et al.,2021,2023).Among the various approaches employed for SeNP synthesis,green synthesis has emerged as a noteworthy and eco-friendly methodology.Keshtmand et al.(2023)underscored the significance of green-synthesized SeNPs,presenting a compelling avenue in this domain.This innovative strategy harnesses the potential of natural resources,such as plant extracts or microorganisms,to facilitate the production of SeNPs.
基金National Key Research and Development Project of China(2023YFC2306600)Key Program of the National Natural Science Foundation of China(82430070)+6 种基金Shanghai Pujiang Program(No.23PJ1410800)National Natural Science Foundation of China(82072260,32370168)Eastern Talent Plan Leading Project,Shanghai Hospital Development Center Foundation(SHDC12022121)Shanghai 2020“Science and Technology Innovation Action Plan”Medical Innovation Research Special(20Z11900900)Three-year Action Plan(2023-2025)Key Discipline Program on Public Health System Construction of Shanghai(GWVI-11.1-15)Construction of the Major Infectious Disease Medical Treatment System(GWVI-2.2).
文摘Dear Editor,The COVID-19 pandemic,caused by the severe acute respiratory syndrome coronavirus 2(SARS-CoV-2),has resulted in millions of deaths worldwide.It poses significant challenges in the management of immunocompromised patients,particularly people with HIV(PWH).Whether PWH are more vulnerable to COVID with more adverse outcomes has been extensively studied,but the findings are inconsistent.Many cohort studies and meta-analyses support that PWH have a higher risk of SARSCoV-2 infection and more severe COVID-19 outcomes(Bertagnolio et al.,2022;Ssentongo et al.,2021).
