This study explores the corrosion issues arising from the coupled combustion of coal and biomass and proposes potential solutions.Biomass,as a renewable energy source,offers advantages in energy-saving and carbon redu...This study explores the corrosion issues arising from the coupled combustion of coal and biomass and proposes potential solutions.Biomass,as a renewable energy source,offers advantages in energy-saving and carbon reduction.However,the corrosive effects of alkali metal compounds,sulfur(S)and chlorine(Cl)elements in the ash after combustion cannot be underestimated due to the high volatile content of biomass fuels.We investigate the corrosion mechanisms,as well as the transfer of Cl and alkali metal elements during this process.Comparative corrosion analyses are conducted among coal-fired boilers,pure biomass boilers and boilers with coupled combustion.Various biomass types in co-firing are studied to understand different corrosion outcomes.The main factors influencing corrosion include the physicochemical properties of biomass feedstock,furnace temperature and heating surface materials,with the chemical composition and ash content of biomass playing a dominant role.Currently,the methods used for anti-corrosion include water washing pretreatment of biomass feedstock,application of novel alloys and coatings and the development of additives to inhibit fouling,ash deposition and corrosion.Efficient inhibitors are economical and easy to produce.Additionally,biomass can be converted into biomass gasification gas,although challenges related to tar still need to be addressed.展开更多
For the aqueous Zn-ion battery,dendrite formation,corrosion,and interfacial parasitic reactions are major issues,which greatly inhibits their practical application.How to develop a method of Zn construction or treatme...For the aqueous Zn-ion battery,dendrite formation,corrosion,and interfacial parasitic reactions are major issues,which greatly inhibits their practical application.How to develop a method of Zn construction or treatment to solve these issues for Zn anodes are still great challenges.Herein,a simple and cheap metal passivation technique is proposed for Zn anodes from a corrosion science perspective.Similar to the metal anticorrosion engineering,the formed interfacial protective layer in a chemical way can sufficiently solve the corrosion issues.Furthermore,the proposed passivity approach can reconstruct Zn surface-preferred crystal planes,exposing more(002)planes and improving surface hydrophilicity,which inhibits the formation of Zn dendrites and hydrogen evolution effectively.As expected,the passivated Zn achieves outstanding cycling life(1914 h)with low voltage polarization(<40 mV).Even at 6 mA cm^(−2) and 3 mA h cm^(−2),it can achieve stable Zn deposition over 460 h.The treated Zn anode coupled with MnO_(2) cathode shows prominently reinforced full batteries service life,making it a potential Zn anode candidate for excellent performance aqueous Zn-ion batteries.The proposed passivation approach provides a guideline for other metal electrodes preparation in various batteries and establishes the connections between corrosion science and batteries.展开更多
Background: low back pain affects many individuals, with 80% classified as non-specific low back pain (NSLBP) due to mechanical rather than structural issues. The link between pelvic alignment and lumbopelvic-hip rota...Background: low back pain affects many individuals, with 80% classified as non-specific low back pain (NSLBP) due to mechanical rather than structural issues. The link between pelvic alignment and lumbopelvic-hip rotation movement for NSLBP is controversial. Methods: twenty males with NSLBP and 20 healthy males participated. Data collected included static pelvic asymmetry and active lumbopelvic-hip rotation with motion capture system for kinematic analysis. Results: Unpaired T test was used to compare the difference of kinematic parameters between two groups. NSLBP group showed significantly larger angles between the ASIS-PSIS line and the z-axis (p Conclusion: Evaluations focusing on bone structure alone may be inadequate. A more comprehensive approach including functional assessments like muscle strength and range of motion could be beneficial. Integrating lumbopelvic-hip movement patterns and pelvic symmetry into clinical assessments should be considered, as they may be influenced by physical activity.展开更多
Background: Low back pain (LBP) is a very common health problem amongst the general population and a major cause of disability that affects work performance and well-being. Healthcare workers (HCWs) are especially at ...Background: Low back pain (LBP) is a very common health problem amongst the general population and a major cause of disability that affects work performance and well-being. Healthcare workers (HCWs) are especially at risk of developing LBP because of physical and emotional factors. Little is known about the burden of LBP in Cameroon. Objective: To determine the prevalence of low back pain and identify its associated factors among healthcare workers. Methods: A cross-sectional study using a self-administered questionnaire was conducted among healthcare workers in the Yaound Central Hospital and the Yaound University Teaching Hospital. The questionnaire collected data regarding recent, past year and lifetime occurrences of LBP, socio-demographics and work conditions. Data were analysed using IBM Statistical Package for Social Sciences (SPSS) version 26. Results: A total number of 268 HCWs participated in the study, including 197 (73.5%) females and 71 (26.5%) males. The mean age of the study participants was 40.60 8.38 years (extremes of 20 and 65 years). The lifetime, annual, and point prevalences of LBP among the participants were 67.5% (CI: 61.6 - 73.1), 61.5% (CI: 55.6 - 67.1) and 35.7% (CI: 29.7 - 41.5) respectively. Multivariate analysis confirmed a moderate stress level, a sedentary lifestyle, working in the medicine and specialities department, lifting heavy objects and bending to work as associated factors to LBP. Most sufferers had a minimal functional disability (65.7%) while 34.3% had a moderate to severe disability. Conclusions: Healthcare providers have a considerably high prevalence of low back pain. Factors associated with LBP found in this study were similar to those widely recognized in the literature. A substantial proportion of healthcare providers are suffering from functional disability associated with low back pain, affecting their social and work lives. There is a need for multilevel interventions to prevent and control low back pain in this highly vulnerable occupational group.展开更多
文摘This study explores the corrosion issues arising from the coupled combustion of coal and biomass and proposes potential solutions.Biomass,as a renewable energy source,offers advantages in energy-saving and carbon reduction.However,the corrosive effects of alkali metal compounds,sulfur(S)and chlorine(Cl)elements in the ash after combustion cannot be underestimated due to the high volatile content of biomass fuels.We investigate the corrosion mechanisms,as well as the transfer of Cl and alkali metal elements during this process.Comparative corrosion analyses are conducted among coal-fired boilers,pure biomass boilers and boilers with coupled combustion.Various biomass types in co-firing are studied to understand different corrosion outcomes.The main factors influencing corrosion include the physicochemical properties of biomass feedstock,furnace temperature and heating surface materials,with the chemical composition and ash content of biomass playing a dominant role.Currently,the methods used for anti-corrosion include water washing pretreatment of biomass feedstock,application of novel alloys and coatings and the development of additives to inhibit fouling,ash deposition and corrosion.Efficient inhibitors are economical and easy to produce.Additionally,biomass can be converted into biomass gasification gas,although challenges related to tar still need to be addressed.
基金financialy supported by the National Key R&D Program of China(Grant No.2018YFB0905400)the National Natural Science Foundation of China(Grant Nos.22075331,51702376)+2 种基金the Fundamental Research Funds for the Central Universities(19lgzd02)the Guangdong Pearl River Talents Plan(2019QN01L117)the National Thousand Youth Talents Project of the Chinese Government
文摘For the aqueous Zn-ion battery,dendrite formation,corrosion,and interfacial parasitic reactions are major issues,which greatly inhibits their practical application.How to develop a method of Zn construction or treatment to solve these issues for Zn anodes are still great challenges.Herein,a simple and cheap metal passivation technique is proposed for Zn anodes from a corrosion science perspective.Similar to the metal anticorrosion engineering,the formed interfacial protective layer in a chemical way can sufficiently solve the corrosion issues.Furthermore,the proposed passivity approach can reconstruct Zn surface-preferred crystal planes,exposing more(002)planes and improving surface hydrophilicity,which inhibits the formation of Zn dendrites and hydrogen evolution effectively.As expected,the passivated Zn achieves outstanding cycling life(1914 h)with low voltage polarization(<40 mV).Even at 6 mA cm^(−2) and 3 mA h cm^(−2),it can achieve stable Zn deposition over 460 h.The treated Zn anode coupled with MnO_(2) cathode shows prominently reinforced full batteries service life,making it a potential Zn anode candidate for excellent performance aqueous Zn-ion batteries.The proposed passivation approach provides a guideline for other metal electrodes preparation in various batteries and establishes the connections between corrosion science and batteries.
文摘Background: low back pain affects many individuals, with 80% classified as non-specific low back pain (NSLBP) due to mechanical rather than structural issues. The link between pelvic alignment and lumbopelvic-hip rotation movement for NSLBP is controversial. Methods: twenty males with NSLBP and 20 healthy males participated. Data collected included static pelvic asymmetry and active lumbopelvic-hip rotation with motion capture system for kinematic analysis. Results: Unpaired T test was used to compare the difference of kinematic parameters between two groups. NSLBP group showed significantly larger angles between the ASIS-PSIS line and the z-axis (p Conclusion: Evaluations focusing on bone structure alone may be inadequate. A more comprehensive approach including functional assessments like muscle strength and range of motion could be beneficial. Integrating lumbopelvic-hip movement patterns and pelvic symmetry into clinical assessments should be considered, as they may be influenced by physical activity.
文摘Background: Low back pain (LBP) is a very common health problem amongst the general population and a major cause of disability that affects work performance and well-being. Healthcare workers (HCWs) are especially at risk of developing LBP because of physical and emotional factors. Little is known about the burden of LBP in Cameroon. Objective: To determine the prevalence of low back pain and identify its associated factors among healthcare workers. Methods: A cross-sectional study using a self-administered questionnaire was conducted among healthcare workers in the Yaound Central Hospital and the Yaound University Teaching Hospital. The questionnaire collected data regarding recent, past year and lifetime occurrences of LBP, socio-demographics and work conditions. Data were analysed using IBM Statistical Package for Social Sciences (SPSS) version 26. Results: A total number of 268 HCWs participated in the study, including 197 (73.5%) females and 71 (26.5%) males. The mean age of the study participants was 40.60 8.38 years (extremes of 20 and 65 years). The lifetime, annual, and point prevalences of LBP among the participants were 67.5% (CI: 61.6 - 73.1), 61.5% (CI: 55.6 - 67.1) and 35.7% (CI: 29.7 - 41.5) respectively. Multivariate analysis confirmed a moderate stress level, a sedentary lifestyle, working in the medicine and specialities department, lifting heavy objects and bending to work as associated factors to LBP. Most sufferers had a minimal functional disability (65.7%) while 34.3% had a moderate to severe disability. Conclusions: Healthcare providers have a considerably high prevalence of low back pain. Factors associated with LBP found in this study were similar to those widely recognized in the literature. A substantial proportion of healthcare providers are suffering from functional disability associated with low back pain, affecting their social and work lives. There is a need for multilevel interventions to prevent and control low back pain in this highly vulnerable occupational group.
