In this work,a series of experiments are carried out to investigate the effect of charge/discharge rates(1,2,3 and 4 C)and state of charges(SOCs,namely 0%,50%,75%and 100%)on thermal runaway(TR)and fire behavior of lit...In this work,a series of experiments are carried out to investigate the effect of charge/discharge rates(1,2,3 and 4 C)and state of charges(SOCs,namely 0%,50%,75%and 100%)on thermal runaway(TR)and fire behavior of lithium iron phosphate(LFP)batteries.The TR process caused by overheating LFP batteries is usually divided into four stages,with high temperatures and fire risks.High-rate charge and discharge damage the internal morphology and structural stability of materials seriously.The TR behavior of battery is fully aggravated,which is further manifested by the advanced opening of the safety vent,release of gas and occurrence of TR.With the increase of charging rate,the deteriorated TR characteristics can be discerned,such as the lower TR temperature,the shorter TR time,and the more serious TR consequences.Such changes can be assigned to the decline of battery stability.In addition,the battery SOC greatly impacts safety,especially the flame temperature and the severity of consequences.As for the 100%SOC battery cycled at 4 C,there is still a high risk of thermal runaway propagation at the position 1 m far away from the battery.This work helps to realize the TR and fire features of battery in-depth,enlightening the safety protection of battery.展开更多
Multimodal ultrasonic vibration(UV)assisted micro-forming has been widely investigated for its advantages of further reducing forming loads and improving forming quality.However,the influence mechanism of different UV...Multimodal ultrasonic vibration(UV)assisted micro-forming has been widely investigated for its advantages of further reducing forming loads and improving forming quality.However,the influence mechanism of different UV modes on microstructure evolution and mechanical properties was still unclear.Mul-timodal UV assisted micro-compression tests on T2 copper with different grains and sample sizes were conducted in this study.The microstructure evolution for different UV modes was observed by EBSD.The results showed that the true stress reduction caused by UV was increased sequentially with tool ultrasonic vibration(TV),mold ultrasonic vibration(MV)and compound ultrasonic vibration(CV).The region of grain deformation was shifted along the direction of UV,and the MV promoted the uniform distribution of deformation stress.The grain refinement,fiber streamline density,grain deformation and rotation degree were further enhanced under CV,due to the synergistic effect of TV and MV.Additionally,a coupled theoretical model considering both acoustic softening effect and size effect was proposed for describing the mechanical properties.And a physical model of dislocation motion in different UV modes was developed for describing the microstructure evolution.The maximum error between the theoretical and experimental results was only 2.39%.This study provides a theoretical basis for the optimization of UV assisted micro-forming process.展开更多
Semicrystalline polymers usually undergo multilevel microstructural evolutions with annealing and stretching processes,which is es-sential to tailor the physical properties of the polymer.Here,poly(butylene carbonate)...Semicrystalline polymers usually undergo multilevel microstructural evolutions with annealing and stretching processes,which is es-sential to tailor the physical properties of the polymer.Here,poly(butylene carbonate)(PBC)sheets were prepared via isothermal annealing and unidirectional pre-stretching processes,then the changes of PBC in crystallinity,mechanical properties,thermal properties and microscopic changes before and after annealing and stretching were measured,as well as the relationship between microstructure and macroscopic proper-ties before and after stretching.The strengthening mechanism of PBC was also described.It was demonstrated that shish-kabab structure emerged under the pre-stretching process.With the increase of the tensile ratio,the crystallinity,structure and mechanical properties are in-creased differently.Among them,the crystallinity and tensile strength after annealing-stretching treatment increased to 24.45%and 104.5 MPa,respectively,which were about 1.55 times and 3.4 times of those-without any treatment.展开更多
BACKGROUND As a non-coding RNA molecule,circular RNAs(circRNAs)have significant specificity,and existing data suggest a close relationship between them and the prognosis of patients with gastric cancer(GC).However,thi...BACKGROUND As a non-coding RNA molecule,circular RNAs(circRNAs)have significant specificity,and existing data suggest a close relationship between them and the prognosis of patients with gastric cancer(GC).However,this mechanism has no evidence yet.This article explores the functions of hsa_circRNA_102415 in the malignant behavior and potential downstream signaling of GC cells.The chosen approach is loss of signal and functional gain.AIM To investigate and analyze the relationship between hsa_circRNA_102415 and GC and explore its specific role.Results provide reference for other researchers to develop targeted treatment plans.METHODS The gene expression omnibus(GEO)database can be used to obtain the microarray dataset GSE83521.Data were analyzed using the GEO2R tool to identify differences in circRNAs between normal and GC samples.Quantitative real-time polymerase chain reaction was used to detect differentially expressed genes in GC tissue samples and adjacent cancer tissue samples.GC cells were transfected with small interfering-hsa_circRNA_104415 and plasmid DNA(pcDNA)-hsa_ircRNA_102415.Multiple detection methods,such as Transwell and cell counting kit 8,were used to evaluate cellular physiological activities,including cell invasion and proliferation.The relationship between Wnt family members 2B,microRNA(miR)-4529-5p,etc.,including argonaute 2-RNA immunoprecipitation and luciferase reporter genes was analyzed.Rescue experiments were conducted to analyze and explore the relationship between the malignant behavior of GC cells and hsa_circRNA_102415.RESULTS GEO2R analysis confirmed that hsa_circRNA_102415 had significantly higher expression levels in disease tissues.hsa_circRNA_102415 and miR-4529-5p showed a negative correlation in disease cells,suggesting that hsa_circRNA_102415 upregulated WNT2B expression in GC cells as a competing endogenous RNA for miR-4529-5p.miR-4529-5p mimic or small interfering-WNT2B reversed the effects of pcDNA-hsa_circRNA_102415 or miR-4529-5p inhibitor on cell malignant functions.CONCLUSION miR-4529-5p was used to successfully activate the potential of WNT2B,clarify the role of hsa_circRNA_102415 in GC cells,and provide reference for other researchers to develop targeted treatment plans.展开更多
目的探讨Ilizarov外固定架技术联合髓内钉治疗先天性胫骨假关节(congenital pseudarthrosis of the tiaba,CPT)的临床效果。方法回顾性分析2008年1月至2013年12月解放军第964医院收治的19例CPT患儿资料,均为BoydⅡ型,其中男5例,女14例;...目的探讨Ilizarov外固定架技术联合髓内钉治疗先天性胫骨假关节(congenital pseudarthrosis of the tiaba,CPT)的临床效果。方法回顾性分析2008年1月至2013年12月解放军第964医院收治的19例CPT患儿资料,均为BoydⅡ型,其中男5例,女14例;年龄1~6岁,平均(3.2±1.3)岁。其中7例行Ilizarov外固定架治疗(A组),7例行Ilizarov外固定架+髓内钉治疗(B组),5例行Ilizarov外固定架+骨搬移治疗(C组)。比较不同手术方式的疗效。结果术后随访均>4年。A组首次术后骨性愈合100%;术后再骨折71.4%,踝外翻71.4%,残留膝部畸形28.6%,残留短肢体畸形100%,胫骨前弓14.3%。B组首次术后骨性愈合85.7%;术后再骨折14.3%,残留膝部畸形14.3%,残留短肢体畸形28.6%,胫骨前弓14.3%。C组首次术后骨性愈合100%;术后再骨折100%,踝外翻80%,残留膝部畸形50%,残留短肢体畸形80%,胫骨前弓40%。结论对于CPT的治疗,Ilizarov外固定架联合髓内钉术后再骨折率最低,可通过髓内钉维持骨愈合,减少了并发症。展开更多
采用低温固相燃烧法快速制备了一种具有{111}、{110}和{100}晶面的去顶角八面体LiNi_(0.08)Mn_(1.92)O_(4)(LNMO)正极材料,其高暴露{111}晶面可以减少充放电过程中Mn的溶解,面积相对较小的{110}和{100}晶面可增加Li^(+)快速扩散的通道....采用低温固相燃烧法快速制备了一种具有{111}、{110}和{100}晶面的去顶角八面体LiNi_(0.08)Mn_(1.92)O_(4)(LNMO)正极材料,其高暴露{111}晶面可以减少充放电过程中Mn的溶解,面积相对较小的{110}和{100}晶面可增加Li^(+)快速扩散的通道.测试结果表明,所合成的LNMO具有LiMn_(2)O_(4)特有的立方晶系结构,其颗粒尺寸为亚微米级.LNMO的高温电化学性能优异,在55℃,1和5 C的首次放电比容量分别为109.9和98.0 m Ah/g,分别循环300次后容量保持率为75.8%和80.5%;即使在55℃,10和15 C下分别循环1000次后仍具有48.4%和49.4%的容量保持率,而未掺杂的LiMn_(2)O_(4)于15 C循环1000次后容量损失高达98%.LNMO在55℃有较高的Li^(+)扩散系数(D=3.86×10^(-15)cm^(2)/s)和较小的电荷转移阻抗(循环前、后R_(ct)=158.0和279.8Ω)以及较低的表观活化能(E_(a)=17.63 k J/mol),说明Ni掺杂能够提高Li^(+)在尖晶石型LiMn_(2)O_(4)内的扩散速率及减小锂离子在脱嵌过程中的能垒,从而提高锂离子的扩散速率和倍率性能.对LNMO于55℃循环1000次后的极片进行X射线衍射(XRD)分析,发现LNMO电极材料的晶体结构基本保持不变,表明Ni掺杂提高了锰酸锂材料在55℃长循环过程中的晶体结构稳定性,有效抑制了Jahn-Teller效应及Mn的溶解,显著提升了其高温电化学性能.本工作为尖晶石LiMn_(2)O_(4)电极材料在高温方面的应用提供了借鉴.展开更多
In recent years,with the wide applications and mineral exploitation of rare earth elements,their potential environmental and health effects have caused increasing public concern.Effect of rare earth elements La and Yb...In recent years,with the wide applications and mineral exploitation of rare earth elements,their potential environmental and health effects have caused increasing public concern.Effect of rare earth elements La and Yb on the morphological and functional development of zebrafish embryos were studied.The embryos were exposed to La3+ or Yb3+ at 0,0.01,0.1,0.3,0.5 and 1.0 mmol/L,respectively.Early life stage parameters such as egg and embryo mortality,gastrula development,tail detachment,eyes,somite formation,circulatory system,pigmentation,malformations,hatching rate,length of larvae and mortality were investigated.The results showed La3+ and Yb3+ delayed zebrafish embryo and larval development,decreased survival and hatching rates,and caused tail malformation in a concentration-dependent way.Moreover,heavy rare-earth ytterbium led to more severe acute toxicity of zebrafish embryo than light rare-earth lanthanum.展开更多
基金supported by the National Key Research and Development Plan(2023YFC3009900)the National Natural Science Foundation of China(52104197,52272396,52474233)+3 种基金Hongkong Scholar Program(XJ2022022)Research Grants Council of the Hong Kong Special Administrative Region(City U11214221)Natural Science Foundation of the Jiangsu Higher Education Institutions(21KJB620001)the Open Fund of the State Key Laboratory of Fire Science(SKLFS)Program(HZ2022-KF04)。
文摘In this work,a series of experiments are carried out to investigate the effect of charge/discharge rates(1,2,3 and 4 C)and state of charges(SOCs,namely 0%,50%,75%and 100%)on thermal runaway(TR)and fire behavior of lithium iron phosphate(LFP)batteries.The TR process caused by overheating LFP batteries is usually divided into four stages,with high temperatures and fire risks.High-rate charge and discharge damage the internal morphology and structural stability of materials seriously.The TR behavior of battery is fully aggravated,which is further manifested by the advanced opening of the safety vent,release of gas and occurrence of TR.With the increase of charging rate,the deteriorated TR characteristics can be discerned,such as the lower TR temperature,the shorter TR time,and the more serious TR consequences.Such changes can be assigned to the decline of battery stability.In addition,the battery SOC greatly impacts safety,especially the flame temperature and the severity of consequences.As for the 100%SOC battery cycled at 4 C,there is still a high risk of thermal runaway propagation at the position 1 m far away from the battery.This work helps to realize the TR and fire features of battery in-depth,enlightening the safety protection of battery.
基金supported by the National Key Research and Development Program(No.2022YFB4602502)the Guangdong Basic and Applied Basic Research Foundation(No.2021A1515011991)+2 种基金the Key Research and Development Program Fund of Hubei Province(No.2022BAA057)the state Key Lab-oratory of Solidification Processing in NPU(No.SKLSP202325)the China Scholarship Council Visiting PhD Program(No.202306410136).
文摘Multimodal ultrasonic vibration(UV)assisted micro-forming has been widely investigated for its advantages of further reducing forming loads and improving forming quality.However,the influence mechanism of different UV modes on microstructure evolution and mechanical properties was still unclear.Mul-timodal UV assisted micro-compression tests on T2 copper with different grains and sample sizes were conducted in this study.The microstructure evolution for different UV modes was observed by EBSD.The results showed that the true stress reduction caused by UV was increased sequentially with tool ultrasonic vibration(TV),mold ultrasonic vibration(MV)and compound ultrasonic vibration(CV).The region of grain deformation was shifted along the direction of UV,and the MV promoted the uniform distribution of deformation stress.The grain refinement,fiber streamline density,grain deformation and rotation degree were further enhanced under CV,due to the synergistic effect of TV and MV.Additionally,a coupled theoretical model considering both acoustic softening effect and size effect was proposed for describing the mechanical properties.And a physical model of dislocation motion in different UV modes was developed for describing the microstructure evolution.The maximum error between the theoretical and experimental results was only 2.39%.This study provides a theoretical basis for the optimization of UV assisted micro-forming process.
基金supported by the Sichuan Provincial Regional Innovation Cooperation Project(No.2024YFHZ0159).
文摘Semicrystalline polymers usually undergo multilevel microstructural evolutions with annealing and stretching processes,which is es-sential to tailor the physical properties of the polymer.Here,poly(butylene carbonate)(PBC)sheets were prepared via isothermal annealing and unidirectional pre-stretching processes,then the changes of PBC in crystallinity,mechanical properties,thermal properties and microscopic changes before and after annealing and stretching were measured,as well as the relationship between microstructure and macroscopic proper-ties before and after stretching.The strengthening mechanism of PBC was also described.It was demonstrated that shish-kabab structure emerged under the pre-stretching process.With the increase of the tensile ratio,the crystallinity,structure and mechanical properties are in-creased differently.Among them,the crystallinity and tensile strength after annealing-stretching treatment increased to 24.45%and 104.5 MPa,respectively,which were about 1.55 times and 3.4 times of those-without any treatment.
文摘BACKGROUND As a non-coding RNA molecule,circular RNAs(circRNAs)have significant specificity,and existing data suggest a close relationship between them and the prognosis of patients with gastric cancer(GC).However,this mechanism has no evidence yet.This article explores the functions of hsa_circRNA_102415 in the malignant behavior and potential downstream signaling of GC cells.The chosen approach is loss of signal and functional gain.AIM To investigate and analyze the relationship between hsa_circRNA_102415 and GC and explore its specific role.Results provide reference for other researchers to develop targeted treatment plans.METHODS The gene expression omnibus(GEO)database can be used to obtain the microarray dataset GSE83521.Data were analyzed using the GEO2R tool to identify differences in circRNAs between normal and GC samples.Quantitative real-time polymerase chain reaction was used to detect differentially expressed genes in GC tissue samples and adjacent cancer tissue samples.GC cells were transfected with small interfering-hsa_circRNA_104415 and plasmid DNA(pcDNA)-hsa_ircRNA_102415.Multiple detection methods,such as Transwell and cell counting kit 8,were used to evaluate cellular physiological activities,including cell invasion and proliferation.The relationship between Wnt family members 2B,microRNA(miR)-4529-5p,etc.,including argonaute 2-RNA immunoprecipitation and luciferase reporter genes was analyzed.Rescue experiments were conducted to analyze and explore the relationship between the malignant behavior of GC cells and hsa_circRNA_102415.RESULTS GEO2R analysis confirmed that hsa_circRNA_102415 had significantly higher expression levels in disease tissues.hsa_circRNA_102415 and miR-4529-5p showed a negative correlation in disease cells,suggesting that hsa_circRNA_102415 upregulated WNT2B expression in GC cells as a competing endogenous RNA for miR-4529-5p.miR-4529-5p mimic or small interfering-WNT2B reversed the effects of pcDNA-hsa_circRNA_102415 or miR-4529-5p inhibitor on cell malignant functions.CONCLUSION miR-4529-5p was used to successfully activate the potential of WNT2B,clarify the role of hsa_circRNA_102415 in GC cells,and provide reference for other researchers to develop targeted treatment plans.
文摘目的探讨Ilizarov外固定架技术联合髓内钉治疗先天性胫骨假关节(congenital pseudarthrosis of the tiaba,CPT)的临床效果。方法回顾性分析2008年1月至2013年12月解放军第964医院收治的19例CPT患儿资料,均为BoydⅡ型,其中男5例,女14例;年龄1~6岁,平均(3.2±1.3)岁。其中7例行Ilizarov外固定架治疗(A组),7例行Ilizarov外固定架+髓内钉治疗(B组),5例行Ilizarov外固定架+骨搬移治疗(C组)。比较不同手术方式的疗效。结果术后随访均>4年。A组首次术后骨性愈合100%;术后再骨折71.4%,踝外翻71.4%,残留膝部畸形28.6%,残留短肢体畸形100%,胫骨前弓14.3%。B组首次术后骨性愈合85.7%;术后再骨折14.3%,残留膝部畸形14.3%,残留短肢体畸形28.6%,胫骨前弓14.3%。C组首次术后骨性愈合100%;术后再骨折100%,踝外翻80%,残留膝部畸形50%,残留短肢体畸形80%,胫骨前弓40%。结论对于CPT的治疗,Ilizarov外固定架联合髓内钉术后再骨折率最低,可通过髓内钉维持骨愈合,减少了并发症。
文摘采用低温固相燃烧法快速制备了一种具有{111}、{110}和{100}晶面的去顶角八面体LiNi_(0.08)Mn_(1.92)O_(4)(LNMO)正极材料,其高暴露{111}晶面可以减少充放电过程中Mn的溶解,面积相对较小的{110}和{100}晶面可增加Li^(+)快速扩散的通道.测试结果表明,所合成的LNMO具有LiMn_(2)O_(4)特有的立方晶系结构,其颗粒尺寸为亚微米级.LNMO的高温电化学性能优异,在55℃,1和5 C的首次放电比容量分别为109.9和98.0 m Ah/g,分别循环300次后容量保持率为75.8%和80.5%;即使在55℃,10和15 C下分别循环1000次后仍具有48.4%和49.4%的容量保持率,而未掺杂的LiMn_(2)O_(4)于15 C循环1000次后容量损失高达98%.LNMO在55℃有较高的Li^(+)扩散系数(D=3.86×10^(-15)cm^(2)/s)和较小的电荷转移阻抗(循环前、后R_(ct)=158.0和279.8Ω)以及较低的表观活化能(E_(a)=17.63 k J/mol),说明Ni掺杂能够提高Li^(+)在尖晶石型LiMn_(2)O_(4)内的扩散速率及减小锂离子在脱嵌过程中的能垒,从而提高锂离子的扩散速率和倍率性能.对LNMO于55℃循环1000次后的极片进行X射线衍射(XRD)分析,发现LNMO电极材料的晶体结构基本保持不变,表明Ni掺杂提高了锰酸锂材料在55℃长循环过程中的晶体结构稳定性,有效抑制了Jahn-Teller效应及Mn的溶解,显著提升了其高温电化学性能.本工作为尖晶石LiMn_(2)O_(4)电极材料在高温方面的应用提供了借鉴.
基金supported by the National Natural Science Foundation of China (No. 10875136,10905062,11005118)the Ministry of Science and Technology of China (No. 2011CB933400)
文摘In recent years,with the wide applications and mineral exploitation of rare earth elements,their potential environmental and health effects have caused increasing public concern.Effect of rare earth elements La and Yb on the morphological and functional development of zebrafish embryos were studied.The embryos were exposed to La3+ or Yb3+ at 0,0.01,0.1,0.3,0.5 and 1.0 mmol/L,respectively.Early life stage parameters such as egg and embryo mortality,gastrula development,tail detachment,eyes,somite formation,circulatory system,pigmentation,malformations,hatching rate,length of larvae and mortality were investigated.The results showed La3+ and Yb3+ delayed zebrafish embryo and larval development,decreased survival and hatching rates,and caused tail malformation in a concentration-dependent way.Moreover,heavy rare-earth ytterbium led to more severe acute toxicity of zebrafish embryo than light rare-earth lanthanum.