The effects of nano-CaO contents on the microstructure,mechanical properties and corrosion resistance of lean Mg-1Zn alloy were investigated.The results showed that the addition of nano-CaO significantly refined the g...The effects of nano-CaO contents on the microstructure,mechanical properties and corrosion resistance of lean Mg-1Zn alloy were investigated.The results showed that the addition of nano-CaO significantly refined the grain size and improved mechanical properties of the Mg-1Zn alloy.At the same time,CaO reacted with molten Mg in situ to form nano-MgO,whose corrosion product in SBF solution was the same with the degradation product of Mg matrix,resulting in the enhanced compactness of the Mg(OH)_(2) layer and reduced corrosion rate of matrix.The Mg-1Zn alloy had lower corrosion resistance due to excessively large grain size and shedding of corrosion products.The composite with 0.5 wt.%CaO had the best corrosion resistance with a weight loss of 9.875 mg·y^(-1)·mm^(-2)due to the small number of Ca_(2)Mg_(6)Zn_(3) phase and suitable grain size.While for composites with high content of CaO(0.7 wt.%and 1.0 wt.%),they had lower corrosion resistance due to the coexistence of large number of Ca_(2)Mg_(6)Zn_(3) and Mg_(2)Ca at grain boundaries,especially for 1.0 wt.%CaO composite,resulting from the strong micro-galvanic corrosion.展开更多
BACKGROUND A new nomenclature consensus has emerged for liver diseases that were previously known as non-alcoholic fatty liver disease(NAFLD)and metabolic dysfunction-associated fatty liver disease(MAFLD).They are now...BACKGROUND A new nomenclature consensus has emerged for liver diseases that were previously known as non-alcoholic fatty liver disease(NAFLD)and metabolic dysfunction-associated fatty liver disease(MAFLD).They are now defined as metabolic dysfunction-associated steatotic liver disease(MASLD),which includes cardiometabolic criteria in adults.This condition,extensively studied in obese or overweight patients,constitutes around 30%of the population,with a steady increase worldwide.Lean patients account for approximately 10%-15%of the MASLD population.However,the pathogenesis is complex and is not well understood.AIM To systematically review the literature on the diagnosis,pathogenesis,characteristics,and prognosis in lean MASLD patients and provide an interpretation of these new criteria.METHODS We conducted a comprehensive database search on PubMed and Google Scholar between January 2012 and September 2023,specifically focusing on lean NAFLD,MAFLD,or MASLD patients.We include original articles with patients aged 18 years or older,with a lean body mass index categorized according to the World Health Organization criteria,using a cutoff of 25 kg/m2 for the general population and 23 kg/m2 for the Asian population.RESULTS We include 85 studies in our analysis.Our findings revealed that,for lean NAFLD patients,the prevalence rate varied widely,ranging from 3.8%to 34.1%.The precise pathogenesis mechanism remained elusive,with associations found in genetic variants,epigenetic modifications,and adaptative metabolic response.Common risk factors included metabolic syndrome,hypertension,and type 2 diabetes mellitus,but their prevalence varied based on the comparison group involving lean patients.Regarding non-invasive tools,Fibrosis-4 index outperformed the NAFLD fibrosis score in lean patients.Lifestyle modifications aided in reducing hepatic steatosis and improving cardiometabolic profiles,with some medications showing efficacy to a lesser extent.However,lean NAFLD patients exhibited a worse prognosis compared to the obese or overweight counterpart.CONCLUSION MASLD is a complex disease comprising epigenetic,genetic,and metabolic factors in its pathogenesis.Results vary across populations,gender,and age.Limited data exists on clinical practice guidelines for lean patients.Future studies employing this new nomenclature can contribute to standardizing and generalizing results among lean patients with steatotic liver disease.展开更多
Lithium–sulfur(Li–S) batteries have received widespread attention, and lean electrolyte Li–S batteries have attracted additional interest because of their higher energy densities. This review systematically analyze...Lithium–sulfur(Li–S) batteries have received widespread attention, and lean electrolyte Li–S batteries have attracted additional interest because of their higher energy densities. This review systematically analyzes the effect of the electrolyte-to-sulfur(E/S) ratios on battery energy density and the challenges for sulfur reduction reactions(SRR) under lean electrolyte conditions. Accordingly, we review the use of various polar transition metal sulfur hosts as corresponding solutions to facilitate SRR kinetics at low E/S ratios(< 10 μL mg~(-1)), and the strengths and limitations of different transition metal compounds are presented and discussed from a fundamental perspective. Subsequently, three promising strategies for sulfur hosts that act as anchors and catalysts are proposed to boost lean electrolyte Li–S battery performance. Finally, an outlook is provided to guide future research on high energy density Li–S batteries.展开更多
This paper presents a study on the design strategy of leaning-type arch bridges.The main characteristics of leaning-type arch bridges are first introduced;Kunshan Yufeng Bridge is taken as an example to discuss differ...This paper presents a study on the design strategy of leaning-type arch bridges.The main characteristics of leaning-type arch bridges are first introduced;Kunshan Yufeng Bridge is taken as an example to discuss different aspects of a design strategy,which includes self-system optimization,selection of beam length and bridge deck position,and other aspects.This paper can be used as a reference to further improve and develop bridge design.展开更多
There are frequent failures in the project delivery in time and increasing the waste in Oman construction industry.Lean Construction(LC)principles which are lean thinking in design and construction process may be a po...There are frequent failures in the project delivery in time and increasing the waste in Oman construction industry.Lean Construction(LC)principles which are lean thinking in design and construction process may be a possible solution.Hence,the paper is aimed on exploring the status of the LC practices and its impact on Omani Construction Industry(OCI).The paper presents barriers,potential benefits,and the measures of suitability and acceptability of LC principles.A quantitative research approach was adopted and research data was collected using an online questionnaire survey in Oman.The data were analysed and results are presented in tables and charts followed by critical discussions.The survey found that onethird of the construction professionals have a good awareness and half of them having a higher level awareness about LC practices.More than one third of the construction organisations are adopting LC principles with a high consensus on the suitability and acceptability,and they recognised that time commitment is necessary for the successful implementation and achieve benefits.The study concludes that the reduction in project delivery time and construction at site waste is the key advantage of implementing LC priciples in design and construction stages in the omani construction industry.展开更多
Much has been published on the characteristics of type 2 diabetes mellitus and its association with the epidemic of obesity.But relatively little is known about the incidence of lean diabetes,progression of disease an...Much has been published on the characteristics of type 2 diabetes mellitus and its association with the epidemic of obesity.But relatively little is known about the incidence of lean diabetes,progression of disease and fate of the patients with low-normal body mass index(< 25).Studies in developing countries have shown that the clinical characteristics of these patients include history of childhood malnutrition,poor socioeconomic status,relatively early age of onset and absence of ketosis on withdrawal of insulin.In the United States,recent studies showed that the lean,normal weight diabetes is not rare especially among minority populations.They showed that these patients are mainly males,have higher prevalence of insulin use indicating rapid beta cell failure.They might have increased total,cardiovascular and non cardiovascular mortality when compared to obese diabetic patients.In this review,the epidemiologic and clinical features of lean diabetes are presented.The potential causal mechanisms of this emerging diabetes type that may include genetic,autoimmune,acquired and behavioral factors are discussed.The need for studies to further elucidate the causation as well as specific prevention and treatment of lean diabetes is emphasized.展开更多
BACKGROUND Nonalcoholic fatty liver disease(NAFLD)is one of the most common chronic diseases in the world.Nowadays,the percentage of non-obese or lean patients with NAFLD is increasing.NAFLD in non-obese populations,e...BACKGROUND Nonalcoholic fatty liver disease(NAFLD)is one of the most common chronic diseases in the world.Nowadays,the percentage of non-obese or lean patients with NAFLD is increasing.NAFLD in non-obese populations,especially the lean subgroup with a normal waist circumference(WC),might lead to more problems than obese individuals,as these individuals may not visit clinics for NAFLD diagnosis or ignore the diagnosis of NAFLD.If the precise characteristics of these populations,especially the lean subgroup,are identified,the clinicians would be able to provide more appropriate advice and treatment to these populations.AIM To investigate the prevalence,clinical characteristics,risk factors,and possible indicators for NAFLD in lean Chinese adults with a normal WC.METHODS People without diabetes mellitus or significant alcohol consumption who underwent routine health examinations were included.Their fatty liver index(FLI),abdominal ultrasonography results,and controlled attenuation parameter were all assessed.Genotyping for single-nucleotide polymorphisms associated with NAFLD was performed in another small group consisting of biopsy-proven NAFLD subjects and healthy controls.RESULTS A total of 2715 subjects who underwent routine health examinations were included in the study.Among 810 lean participants with a normal WC,142(17.5%)fulfilled the diagnostic criteria for NAFLD.Waist-height ratio,hemoglobin,platelets,and triglycerides were significant factors associated with the presence of NAFLD in these participants.The appropriate cut-off value of the FLI score in screening for NAFLD in the lean subjects with a normal WC was 25.15,which had a 77.8%sensitivity and 75.9%specificity.There was no significant difference in the single-nucleotide polymorphisms in the SIRT1,APOC3,PNPLA3,AGTR1,and PPARGC1A genes between lean subjects with and without NAFLD(P<0.05).CONCLUSION NAFLD is not uncommon in lean Chinese adults even with a normal WC.Metabolic factors,rather than genetic factors,may play important roles in the development of NAFLD in this population.A lower cut-off value of the FLI score in screening for NAFLD should be used for lean Chinese adults with a normal WC.展开更多
In this work, the microstructure and the strain partitioning of lean duplex stainless steel 2101 (LDX 2101) during different hot-rolling processes are investigated by optical microscopy and electron-backscattered diff...In this work, the microstructure and the strain partitioning of lean duplex stainless steel 2101 (LDX 2101) during different hot-rolling processes are investigated by optical microscopy and electron-backscattered diffraction (EBSD). The results show that the LDX 2101 exhibits poor thermoplasticity at high temperature. The four-pass hot-rolled plates show fewer edge-cracking defects and superior thermoplasticity compared with the two-pass hot-rolled plates prepared at different temperature. The phase boundary is the weakest site in the LDX 2101. The cracks are initiated and propagated along the phase boundaries during the hot-rolling process. According to the EBSD analysis, the increase of the hot-rolling pass can dramatically improve the strain distribution in ferrite and austenite phases and promote the strain transmission in the constituent phases, thereby improving the coordinated deformation ability of the two phases. This effect further in- creases the thermoplasticity and reduces the formation of edge cracks in LDX 2101.展开更多
Lithium-sulfur(Li-S)batteries possess overwhelming energy density of 2654 Wh kg-1,and are considered as the next-generation battery technology for energy demanding applications.Flooded electrolytes are ubiquitously em...Lithium-sulfur(Li-S)batteries possess overwhelming energy density of 2654 Wh kg-1,and are considered as the next-generation battery technology for energy demanding applications.Flooded electrolytes are ubiquitously employed in cells to ensure sufficient redox kinetics and preclude the interference of the electrolyte depletion due to side reactions with the lithium metal anode.This strategy is capable of enabling long-lasting,high-capacity and excellent-rate battery performances,but it mask the requirements of practical Li-S batteries,where high-sulfur-loading/content and lean electrolyte are prerequisite to realize the energy-dense Li-S batteries.Sparingly and highly solvating electrolytes have emerged as effective yet simple approaches to decrease the electrolyte/sulfur ratio through altering sulfur species and exerting new reaction pathways.Sparingly solvating electrolytes are characterized by few free solvents to solvate lithium polysulfides,rendering a quasi-solid sulfur conversion and decoupling the reaction mechanisms from electrolyte quantity used in cells;while highly solvating electrolytes adopt highdonicity or high-permittivity solvents and take their advantages of strong solvation ability toward polysulfide intermediates,thereby favoring the polysulfide formation and stabilizing unique radicals,which subsequently accelerate redox kinetics.Both solvation chemistry approaches have their respective features to allow the operation of cells under electrolyte-starved conditions.This Review discusses their unique features and basic physicochemical properties in the working Li-S batteries,presents remaining technical and scientific issues and provides future directions for the electrolyte chemistry to attain highenergy Li-S batteries.展开更多
AIM:To study the prevalence and clinical biochemical,blood cell and metabolic features of lean-non-alcoholic fatty liver disease(lean-NAFLD)and its association with other diseases.METHODS:Demographic,biochemical and b...AIM:To study the prevalence and clinical biochemical,blood cell and metabolic features of lean-non-alcoholic fatty liver disease(lean-NAFLD)and its association with other diseases.METHODS:Demographic,biochemical and blood examinations were conducted in all the subjects in this study.We classified the subjects into four groups according to their weight and NAFLD status:lean-control,lean-NAFLD[body mass index(BMI)<24 kg/m2],overweight-obese control and overweight-obese NAFLD.One-way analysis of variance(ANOVA)was used to compare the means of continuous variables(age,BMI,blood pressure,glucose,lipid,insulin,liver enzymes and blood cell counts)and theχ2 test was used to compare the differences in frequency of categorical variables(sex,education,physical activity,smoking,alcohol consumption and prevalence of hypertension,hyperlipidemia,diabetes,metabolic syndrome central obesity and obesity).Both univariate and multivariate logistic regression models were adopted to calculate odds ratios(ORs)and predict hyperlipidemia,hypertension,diabetes and metabolic syndrome when we respectively set all controls,lean-control and overweightobese-control as references.In multivariate logistic regression models,we adjusted potential confounding factors,including age,sex,smoking,alcohol consumption and physical activity.RESULTS:The prevalence of NAFLD was very high in China.NAFLD patients were older,had a higher BMI,waist circumference,blood pressure,fasting blood glucose,insulin,blood lipid,liver enzymes and uric acid than the controls.Although lean-NAFLD patients had lower BMI and waist circumstance,they had significantly higher visceral adiposity index than overweightobese controls.Lean-NAFLD patients had comparable triglyceride,cholesterin and low-density lipoprotein cholesterin to overweight-obese NAFLD patients.In blood cell examination,both lean and overweightobese NAFLD was companied by higher white blood cell count,red blood cell count,hemoglobin and hematocrit value.All NAFLD patients were at risk of hyperlipidemia,hypertension,diabetes and metabolic syndrome(Met S).Lean-NAFLD was more strongly associated with diabetes(OR=2.47,95%CI:1.14-5.35),hypertension(OR=1.72,95%CI:1.00-2.96)and Met S(OR=3.19,95%CI:1.17-4.05)than overweight-obese-NAFLD(only OR for Met S was meaningful:OR=1.89,95%CI:1.29-2.77).NAFLD patients were more likely to have central obesity(OR=1.97,95%CI:1.38-2.80),especially in lean groups(OR=2.17,95%CI:1.17-4.05).CONCLUSION:Lean-NAFLD has unique results in demographic,biochemical and blood examinations,and adds significant risk for diabetes,hypertension and Met S in lean individuals.展开更多
As a primary type of clean energy,methane is also the second most important greenhouse gas after CO_(2)due to the high global warming potential.Large quantities of lean methane(0.1–1.0 vol%)are emitted into the atmos...As a primary type of clean energy,methane is also the second most important greenhouse gas after CO_(2)due to the high global warming potential.Large quantities of lean methane(0.1–1.0 vol%)are emitted into the atmosphere without any treatment during coal mine,oil,and natural gas production,thus leading to energy loss and greenhouse effect.In general,it is challenging to utilize lean methane due to its low concentration and flow instability,while catalytic combustion is a vital pathway to realize an efficient utilization of lean methane owing to the reduced emissions of polluting gases(e.g.,NOxand CO)during the reaction.In particular,to efficiently convert lean methane,it necessitates both the designs of highly active and stable heterogeneous catalysts that accelerate lean methane combustion at low temperatures and smart reactors that enable autothermal operation by optimizing heat management.In this review,we discuss the in-depth development,challenges,and prospects of catalytic lean methane combustion technology in various configurations,with particular emphasis on heat management from the point of view of material design combined with reactor configuration.The target is to describe a framework that can correlate the guiding principles among catalyst design,device innovation and system optimization,inspiring the development of groundbreaking combustion technology for the efficient utilization of lean methane.展开更多
基金the financial support for this work from the National Natural Science Foundation of China(Nos.52171241,52201301 and 51871166)。
文摘The effects of nano-CaO contents on the microstructure,mechanical properties and corrosion resistance of lean Mg-1Zn alloy were investigated.The results showed that the addition of nano-CaO significantly refined the grain size and improved mechanical properties of the Mg-1Zn alloy.At the same time,CaO reacted with molten Mg in situ to form nano-MgO,whose corrosion product in SBF solution was the same with the degradation product of Mg matrix,resulting in the enhanced compactness of the Mg(OH)_(2) layer and reduced corrosion rate of matrix.The Mg-1Zn alloy had lower corrosion resistance due to excessively large grain size and shedding of corrosion products.The composite with 0.5 wt.%CaO had the best corrosion resistance with a weight loss of 9.875 mg·y^(-1)·mm^(-2)due to the small number of Ca_(2)Mg_(6)Zn_(3) phase and suitable grain size.While for composites with high content of CaO(0.7 wt.%and 1.0 wt.%),they had lower corrosion resistance due to the coexistence of large number of Ca_(2)Mg_(6)Zn_(3) and Mg_(2)Ca at grain boundaries,especially for 1.0 wt.%CaO composite,resulting from the strong micro-galvanic corrosion.
文摘BACKGROUND A new nomenclature consensus has emerged for liver diseases that were previously known as non-alcoholic fatty liver disease(NAFLD)and metabolic dysfunction-associated fatty liver disease(MAFLD).They are now defined as metabolic dysfunction-associated steatotic liver disease(MASLD),which includes cardiometabolic criteria in adults.This condition,extensively studied in obese or overweight patients,constitutes around 30%of the population,with a steady increase worldwide.Lean patients account for approximately 10%-15%of the MASLD population.However,the pathogenesis is complex and is not well understood.AIM To systematically review the literature on the diagnosis,pathogenesis,characteristics,and prognosis in lean MASLD patients and provide an interpretation of these new criteria.METHODS We conducted a comprehensive database search on PubMed and Google Scholar between January 2012 and September 2023,specifically focusing on lean NAFLD,MAFLD,or MASLD patients.We include original articles with patients aged 18 years or older,with a lean body mass index categorized according to the World Health Organization criteria,using a cutoff of 25 kg/m2 for the general population and 23 kg/m2 for the Asian population.RESULTS We include 85 studies in our analysis.Our findings revealed that,for lean NAFLD patients,the prevalence rate varied widely,ranging from 3.8%to 34.1%.The precise pathogenesis mechanism remained elusive,with associations found in genetic variants,epigenetic modifications,and adaptative metabolic response.Common risk factors included metabolic syndrome,hypertension,and type 2 diabetes mellitus,but their prevalence varied based on the comparison group involving lean patients.Regarding non-invasive tools,Fibrosis-4 index outperformed the NAFLD fibrosis score in lean patients.Lifestyle modifications aided in reducing hepatic steatosis and improving cardiometabolic profiles,with some medications showing efficacy to a lesser extent.However,lean NAFLD patients exhibited a worse prognosis compared to the obese or overweight counterpart.CONCLUSION MASLD is a complex disease comprising epigenetic,genetic,and metabolic factors in its pathogenesis.Results vary across populations,gender,and age.Limited data exists on clinical practice guidelines for lean patients.Future studies employing this new nomenclature can contribute to standardizing and generalizing results among lean patients with steatotic liver disease.
基金the Research Foundation-Flanders (FWO) for a Research Project (G0B3218N)the financial support by the National Natural Science Foundation of China (22005054)+3 种基金Natural Science Foundation of Fujian Province (2021J01149)State Key Laboratory of Structural Chemistry (20200007)Sichuan Science and Technology Program (project No.: 2022ZYD0016 and 2023JDRC0013)the National Natural Science Foundation of China (project No. 21776120)。
文摘Lithium–sulfur(Li–S) batteries have received widespread attention, and lean electrolyte Li–S batteries have attracted additional interest because of their higher energy densities. This review systematically analyzes the effect of the electrolyte-to-sulfur(E/S) ratios on battery energy density and the challenges for sulfur reduction reactions(SRR) under lean electrolyte conditions. Accordingly, we review the use of various polar transition metal sulfur hosts as corresponding solutions to facilitate SRR kinetics at low E/S ratios(< 10 μL mg~(-1)), and the strengths and limitations of different transition metal compounds are presented and discussed from a fundamental perspective. Subsequently, three promising strategies for sulfur hosts that act as anchors and catalysts are proposed to boost lean electrolyte Li–S battery performance. Finally, an outlook is provided to guide future research on high energy density Li–S batteries.
文摘This paper presents a study on the design strategy of leaning-type arch bridges.The main characteristics of leaning-type arch bridges are first introduced;Kunshan Yufeng Bridge is taken as an example to discuss different aspects of a design strategy,which includes self-system optimization,selection of beam length and bridge deck position,and other aspects.This paper can be used as a reference to further improve and develop bridge design.
文摘There are frequent failures in the project delivery in time and increasing the waste in Oman construction industry.Lean Construction(LC)principles which are lean thinking in design and construction process may be a possible solution.Hence,the paper is aimed on exploring the status of the LC practices and its impact on Omani Construction Industry(OCI).The paper presents barriers,potential benefits,and the measures of suitability and acceptability of LC principles.A quantitative research approach was adopted and research data was collected using an online questionnaire survey in Oman.The data were analysed and results are presented in tables and charts followed by critical discussions.The survey found that onethird of the construction professionals have a good awareness and half of them having a higher level awareness about LC practices.More than one third of the construction organisations are adopting LC principles with a high consensus on the suitability and acceptability,and they recognised that time commitment is necessary for the successful implementation and achieve benefits.The study concludes that the reduction in project delivery time and construction at site waste is the key advantage of implementing LC priciples in design and construction stages in the omani construction industry.
文摘Much has been published on the characteristics of type 2 diabetes mellitus and its association with the epidemic of obesity.But relatively little is known about the incidence of lean diabetes,progression of disease and fate of the patients with low-normal body mass index(< 25).Studies in developing countries have shown that the clinical characteristics of these patients include history of childhood malnutrition,poor socioeconomic status,relatively early age of onset and absence of ketosis on withdrawal of insulin.In the United States,recent studies showed that the lean,normal weight diabetes is not rare especially among minority populations.They showed that these patients are mainly males,have higher prevalence of insulin use indicating rapid beta cell failure.They might have increased total,cardiovascular and non cardiovascular mortality when compared to obese diabetic patients.In this review,the epidemiologic and clinical features of lean diabetes are presented.The potential causal mechanisms of this emerging diabetes type that may include genetic,autoimmune,acquired and behavioral factors are discussed.The need for studies to further elucidate the causation as well as specific prevention and treatment of lean diabetes is emphasized.
基金National Key R&D Program of China,No.2017YFC0908900National Natural Science Foundation of China,No.81873565 and No.81900507Hospital Funded Clinical Research,Xinhua Hospital Affiliated to Shanghai Jiao Tong University School of Medicine,No.17CSK04 and No.15LC06.
文摘BACKGROUND Nonalcoholic fatty liver disease(NAFLD)is one of the most common chronic diseases in the world.Nowadays,the percentage of non-obese or lean patients with NAFLD is increasing.NAFLD in non-obese populations,especially the lean subgroup with a normal waist circumference(WC),might lead to more problems than obese individuals,as these individuals may not visit clinics for NAFLD diagnosis or ignore the diagnosis of NAFLD.If the precise characteristics of these populations,especially the lean subgroup,are identified,the clinicians would be able to provide more appropriate advice and treatment to these populations.AIM To investigate the prevalence,clinical characteristics,risk factors,and possible indicators for NAFLD in lean Chinese adults with a normal WC.METHODS People without diabetes mellitus or significant alcohol consumption who underwent routine health examinations were included.Their fatty liver index(FLI),abdominal ultrasonography results,and controlled attenuation parameter were all assessed.Genotyping for single-nucleotide polymorphisms associated with NAFLD was performed in another small group consisting of biopsy-proven NAFLD subjects and healthy controls.RESULTS A total of 2715 subjects who underwent routine health examinations were included in the study.Among 810 lean participants with a normal WC,142(17.5%)fulfilled the diagnostic criteria for NAFLD.Waist-height ratio,hemoglobin,platelets,and triglycerides were significant factors associated with the presence of NAFLD in these participants.The appropriate cut-off value of the FLI score in screening for NAFLD in the lean subjects with a normal WC was 25.15,which had a 77.8%sensitivity and 75.9%specificity.There was no significant difference in the single-nucleotide polymorphisms in the SIRT1,APOC3,PNPLA3,AGTR1,and PPARGC1A genes between lean subjects with and without NAFLD(P<0.05).CONCLUSION NAFLD is not uncommon in lean Chinese adults even with a normal WC.Metabolic factors,rather than genetic factors,may play important roles in the development of NAFLD in this population.A lower cut-off value of the FLI score in screening for NAFLD should be used for lean Chinese adults with a normal WC.
基金financially supported by the National Natural Science Foundation of China (Nos. U1806220 and U1660114)
文摘In this work, the microstructure and the strain partitioning of lean duplex stainless steel 2101 (LDX 2101) during different hot-rolling processes are investigated by optical microscopy and electron-backscattered diffraction (EBSD). The results show that the LDX 2101 exhibits poor thermoplasticity at high temperature. The four-pass hot-rolled plates show fewer edge-cracking defects and superior thermoplasticity compared with the two-pass hot-rolled plates prepared at different temperature. The phase boundary is the weakest site in the LDX 2101. The cracks are initiated and propagated along the phase boundaries during the hot-rolling process. According to the EBSD analysis, the increase of the hot-rolling pass can dramatically improve the strain distribution in ferrite and austenite phases and promote the strain transmission in the constituent phases, thereby improving the coordinated deformation ability of the two phases. This effect further in- creases the thermoplasticity and reduces the formation of edge cracks in LDX 2101.
基金supported by the National Natural Science Foundation of China(21805162 and 21671096)National Key Research and Development Program(2018YFB0104300)+3 种基金Key Program of the Natural Science Foundation of China(51732005)Guangdong Provincial Key Laboratory of Energy Materials for Electric Power(2018B030322001)Shenzhen Key Laboratory of Solid State Batteries(No.ZDSYS201802081843465)Research Support for Postdoctoral Scholars coming to Shenzhen(K19407556)。
文摘Lithium-sulfur(Li-S)batteries possess overwhelming energy density of 2654 Wh kg-1,and are considered as the next-generation battery technology for energy demanding applications.Flooded electrolytes are ubiquitously employed in cells to ensure sufficient redox kinetics and preclude the interference of the electrolyte depletion due to side reactions with the lithium metal anode.This strategy is capable of enabling long-lasting,high-capacity and excellent-rate battery performances,but it mask the requirements of practical Li-S batteries,where high-sulfur-loading/content and lean electrolyte are prerequisite to realize the energy-dense Li-S batteries.Sparingly and highly solvating electrolytes have emerged as effective yet simple approaches to decrease the electrolyte/sulfur ratio through altering sulfur species and exerting new reaction pathways.Sparingly solvating electrolytes are characterized by few free solvents to solvate lithium polysulfides,rendering a quasi-solid sulfur conversion and decoupling the reaction mechanisms from electrolyte quantity used in cells;while highly solvating electrolytes adopt highdonicity or high-permittivity solvents and take their advantages of strong solvation ability toward polysulfide intermediates,thereby favoring the polysulfide formation and stabilizing unique radicals,which subsequently accelerate redox kinetics.Both solvation chemistry approaches have their respective features to allow the operation of cells under electrolyte-starved conditions.This Review discusses their unique features and basic physicochemical properties in the working Li-S batteries,presents remaining technical and scientific issues and provides future directions for the electrolyte chemistry to attain highenergy Li-S batteries.
基金Supported by National Natural Science Fund of China,No.81130049,No.8120218412~(th) China Five-Year Scientific and Technical Plan,No.2012BAI02B02
文摘AIM:To study the prevalence and clinical biochemical,blood cell and metabolic features of lean-non-alcoholic fatty liver disease(lean-NAFLD)and its association with other diseases.METHODS:Demographic,biochemical and blood examinations were conducted in all the subjects in this study.We classified the subjects into four groups according to their weight and NAFLD status:lean-control,lean-NAFLD[body mass index(BMI)<24 kg/m2],overweight-obese control and overweight-obese NAFLD.One-way analysis of variance(ANOVA)was used to compare the means of continuous variables(age,BMI,blood pressure,glucose,lipid,insulin,liver enzymes and blood cell counts)and theχ2 test was used to compare the differences in frequency of categorical variables(sex,education,physical activity,smoking,alcohol consumption and prevalence of hypertension,hyperlipidemia,diabetes,metabolic syndrome central obesity and obesity).Both univariate and multivariate logistic regression models were adopted to calculate odds ratios(ORs)and predict hyperlipidemia,hypertension,diabetes and metabolic syndrome when we respectively set all controls,lean-control and overweightobese-control as references.In multivariate logistic regression models,we adjusted potential confounding factors,including age,sex,smoking,alcohol consumption and physical activity.RESULTS:The prevalence of NAFLD was very high in China.NAFLD patients were older,had a higher BMI,waist circumference,blood pressure,fasting blood glucose,insulin,blood lipid,liver enzymes and uric acid than the controls.Although lean-NAFLD patients had lower BMI and waist circumstance,they had significantly higher visceral adiposity index than overweightobese controls.Lean-NAFLD patients had comparable triglyceride,cholesterin and low-density lipoprotein cholesterin to overweight-obese NAFLD patients.In blood cell examination,both lean and overweightobese NAFLD was companied by higher white blood cell count,red blood cell count,hemoglobin and hematocrit value.All NAFLD patients were at risk of hyperlipidemia,hypertension,diabetes and metabolic syndrome(Met S).Lean-NAFLD was more strongly associated with diabetes(OR=2.47,95%CI:1.14-5.35),hypertension(OR=1.72,95%CI:1.00-2.96)and Met S(OR=3.19,95%CI:1.17-4.05)than overweight-obese-NAFLD(only OR for Met S was meaningful:OR=1.89,95%CI:1.29-2.77).NAFLD patients were more likely to have central obesity(OR=1.97,95%CI:1.38-2.80),especially in lean groups(OR=2.17,95%CI:1.17-4.05).CONCLUSION:Lean-NAFLD has unique results in demographic,biochemical and blood examinations,and adds significant risk for diabetes,hypertension and Met S in lean individuals.
基金financially supported by the National Natural Science Foundation of China(21922606,21876139)the National Natural Science Foundation of Shaanxi Province(2020JQ-919)+2 种基金the Shaanxi Natural Science Fundamental Shaanxi Coal Chemical Joint Fund(2019JLM-14)the Initial Scientific Research Fund for Special Zone’s Talents(XJ18T06)K.C.Wong Education Foundation。
文摘As a primary type of clean energy,methane is also the second most important greenhouse gas after CO_(2)due to the high global warming potential.Large quantities of lean methane(0.1–1.0 vol%)are emitted into the atmosphere without any treatment during coal mine,oil,and natural gas production,thus leading to energy loss and greenhouse effect.In general,it is challenging to utilize lean methane due to its low concentration and flow instability,while catalytic combustion is a vital pathway to realize an efficient utilization of lean methane owing to the reduced emissions of polluting gases(e.g.,NOxand CO)during the reaction.In particular,to efficiently convert lean methane,it necessitates both the designs of highly active and stable heterogeneous catalysts that accelerate lean methane combustion at low temperatures and smart reactors that enable autothermal operation by optimizing heat management.In this review,we discuss the in-depth development,challenges,and prospects of catalytic lean methane combustion technology in various configurations,with particular emphasis on heat management from the point of view of material design combined with reactor configuration.The target is to describe a framework that can correlate the guiding principles among catalyst design,device innovation and system optimization,inspiring the development of groundbreaking combustion technology for the efficient utilization of lean methane.
