Discovery of materials using“bottom-up”or“top-down”approach is of great interest in materials science.Layered materials consisting of two-dimensional(2D)building blocks provide a good platform to explore new mater...Discovery of materials using“bottom-up”or“top-down”approach is of great interest in materials science.Layered materials consisting of two-dimensional(2D)building blocks provide a good platform to explore new materials in this respect.In van der Waals(vdW)layered materials,these building blocks are charge neutral and can be isolated from their bulk phase(top-down),but usually grow on substrate.In ionic layered materials,they are charged and usually cannot exist independently but can serve as motifs to construct new materials(bottom-up).In this paper,we introduce our recently constructed databases for 2D material-substrate interface(2DMSI),and 2D charged building blocks.For 2DMSI database,we systematically build a workflow to predict appropriate substrates and their geometries at substrates,and construct the 2DMSI database.For the 2D charged building block database,1208 entries from bulk material database are identified.Information of crystal structure,valence state,source,dimension and so on is provided for each entry with a json format.We also show its application in designing and searching for new functional layered materials.The 2DMSI database,building block database,and designed layered materials are available in Science Data Bank at https://doi.org/10.57760/sciencedb.j00113.00188.展开更多
Quasi-2D perovskites have attracted tremendous interest for application as lightemission layers in light-emitting diodes(LEDs).However,the heterogeneous n phase and non-uniform distribution still severely limit the fu...Quasi-2D perovskites have attracted tremendous interest for application as lightemission layers in light-emitting diodes(LEDs).However,the heterogeneous n phase and non-uniform distribution still severely limit the further development of quasi-2D perovskite LEDs(Pero-LEDs).Meanwhile,the increased defect density caused by the reduced dimension and grain size induces non-radiative recombination and further deteriorates the device performance.Here,we found that a series of molecules containing phosphoryl chloride functional groups have noticeable enhancement effects on the device performance of quasi-2D Pero-LEDs.Then,we studied the modification mechanism by focusing on the bis(2-oxo-3-oxazolidinyl)phosphinic chloride(BOPCl).It is concluded that the BOPCl can not only regulate the phase distribution by decreasing the crystallization rate but also remain in the grain boundaries and passivate the defects.As a result,the corresponding quasi-2D Pero-LEDs obtained a maximum external quantum efficiency(EQE_(max))of 20.82%and an average EQE(EQE_(ave))of around 20%on the optimal 50 devices,proving excellent reproducibility.Our work provides a new selection of molecular types for regulating the crystallization and passivating the defects of quasi-2D perovskite films.展开更多
In this paper,we obtain Green’s functions of two-dimensional(2D)piezoelectric quasicrystal(PQC)in half-space and bimaterials.Based on the elastic theory of QCs,the Stroh formalism is used to derive the general soluti...In this paper,we obtain Green’s functions of two-dimensional(2D)piezoelectric quasicrystal(PQC)in half-space and bimaterials.Based on the elastic theory of QCs,the Stroh formalism is used to derive the general solutions of displacements and stresses.Then,we obtain the analytical solutions of half-space and bimaterial Green’s functions.Besides,the interfacial Green’s function for bimaterials is also obtained in the analytical form.Before numerical studies,a comparative study is carried out to validate the present solutions.Typical numerical examples are performed to investigate the effects of multi-physics loadings such as the line force,the line dislocation,the line charge,and the phason line force.As a result,the coupling effect among the phonon field,the phason field,and the electric field is prominent,and the butterfly-shaped contours are characteristic in 2D PQCs.In addition,the changes of material parameters cause variations in physical quantities to a certain degree.展开更多
Lithium-sulfur(Li-S)batteries are receiving increasing attention as one of the potential next-generation batteries,owing to their high energy densities and low cost.However,practical Li-S batteries with high energy de...Lithium-sulfur(Li-S)batteries are receiving increasing attention as one of the potential next-generation batteries,owing to their high energy densities and low cost.However,practical Li-S batteries with high energy densities are extremely hindered by the sulfur loss,low Coulombic efficiency,and short cycling life originating from the polysulfide(LiPS)shuttle.In this study,two-dimensional(2D)ZnCo_(2)O_(4) microsheets fabricated by a facile hydrothermal process are employed to modify the separator,for improving the electrochemical performances of Li-S cells.The resulting 2D Zn Co_(2)O_(4)-coated separator features a coating thickness of approximately 10 lm,high ionic conductivity of 1.8 m S/cm,and low mass loading of 0.2 mg/cm^(2).This 2D ZnCo_(2)O_(4)-coated separator effectively inhibits Li PS shuttle by a strong chemical interaction with Li PS as well as promotes the redox kinetics by Zn CO2O4-coated layers,as determined by X-ray photoelectron spectroscopy analysis,self-discharge,time-dependent permeation test,Li symmetric cell test,and Li2S nucleation analyses.Consequently,the Li-S batteries based on the 2D Zn Co_(2)O_(4)-coated separator exhibit a high initial discharge capacity of 1292.2 m Ah/g at 0.1 C.Moreover,they exhibit excellent long cycle stability at 1 and 2 C with capacity retention of 84%and 86%even after800 cycles,corresponding to a capacity fading rate of 0.020%and 0.016%per cycle,respectively.Effectively,these Li-S cells with a high sulfur loading at 5.3 mg/cm^(2) and low electrolyte concentration of 9 l L/mg deliver a high discharge capacity of 4.99 m Ah/cm^(2) after 200 cycles at 0.1 C.展开更多
The authors introduce nonseparable scaling function interpolation and show that its approximation can provide similar convergence properties as scalar wavelet system. Several equivalent statements of accuracy of nonse...The authors introduce nonseparable scaling function interpolation and show that its approximation can provide similar convergence properties as scalar wavelet system. Several equivalent statements of accuracy of nonseparable scaling function are also given. In the numerical experiments, it appears that nonseparable scaling function interpolation has better convergence results than scalar wavelet systems in some cases.展开更多
目的:探讨维生素D治疗新生儿感染性肺炎的效果及其对Toll样受体2(Toll-like receptor 2,TLR2)的影响。方法:选取2021年1月—2022年12月厦门医学院附属第二医院收治的85例新生儿感染性肺炎患儿。根据电脑编号单双差异随机将其分为试验组...目的:探讨维生素D治疗新生儿感染性肺炎的效果及其对Toll样受体2(Toll-like receptor 2,TLR2)的影响。方法:选取2021年1月—2022年12月厦门医学院附属第二医院收治的85例新生儿感染性肺炎患儿。根据电脑编号单双差异随机将其分为试验组(42例)及参考组(43例)。参考组给予常规抗感染治疗,试验组在参考组基础上给予维生素D。比较两组临床疗效、时间指标,治疗前1 d及治疗7 d后炎症因子、免疫功能。结果:试验组治疗总有效率高于参考组,差异有统计学意义(P<0.05)。试验组病原学检查转阴时间、临床症状消失时间早于参考组,住院时间短于参考组,差异有统计学意义(P<0.05)。治疗7 d后,试验组TLR2及白细胞介素-6(interleukin-6,IL-6)、白细胞介素-8(interleukin-8,IL-8)水平均低于参考组,差异有统计学意义(P<0.05)。治疗7 d后,两组CD3^(+)、CD4^(+)、红细胞C3b受体花环率(adherence rate of complement 3b-receptor on the surface of red blood cell,RBC-C3bR)均高于治疗前1 d,试验组高于参考组,两组CD8^(+)、红细胞免疫复合物花环率(immune complex adherence rate of red blood cell,RBC-ICR)均低于治疗前1 d,试验组低于参考组,差异有统计学意义(P<0.05)。结论:维生素D治疗新生儿感染性肺炎的效果较佳,且能减轻炎症反应,改善免疫功能。展开更多
<strong>Background:</strong><span style="font-family:Verdana;"> Heart failure is the commonest cardiovascular complication in type 2 diabetes mellitus. However, subclinical left ventricular...<strong>Background:</strong><span style="font-family:Verdana;"> Heart failure is the commonest cardiovascular complication in type 2 diabetes mellitus. However, subclinical left ventricular dysfunction can’t be detected using 2D echocardiography which </span><span style="font-family:Verdana;">is </span><span style="font-family:;" "=""><span style="font-family:Verdana;">routinely used for cardiac evaluation of diabetic patients. We aimed to determine the prevalence and factors associated to left ventricular global longitudinal strain (LV GLS) impairment in type 2 diabetes Cameroonians patients. </span><b><span style="font-family:Verdana;">Methods:</span></b><span style="font-family:Verdana;"> We conducted a cross-sectional study from January 2019 to June 2019, including type 2 diabetes patients with preserved left ventricle ejection fraction. Clinical and echocardiographic data were collected, and LV GLS was assessed using speckle tracking technique, a value ≤</span></span><span style="font-family:Verdana;"> -</span><span style="font-family:;" "=""><span style="font-family:Verdana;">16% been considered as normal value. </span><b><span style="font-family:Verdana;">Results:</span></b><span style="font-family:Verdana;"> We recruited 95 patients, with a mean age of 57.4 ± 11.8 years old and median diabetes duration of 5 [2 </span></span><span style="font-family:Verdana;">-</span><span style="font-family:Verdana;"> 12] years. Echocardiographic evaluation found 56.3% of left ventricle remodelling, 51.6% of left ventricle diastolic dysfunction and mean left ventricle ejection of 63.3</span><span style="font-family:Verdana;">%</span><span style="font-family:Verdana;"> ± 6.6%. LV GLS impairment was present in 43.2% (95% CI: 32.6 </span><span style="font-family:Verdana;">-</span><span style="font-family:Verdana;"> 53.7) of the participants. After adjustment to all significantly associated factors, Obesity (aOR: 4;95% CI: 1.5 </span><span style="font-family:Verdana;">-</span><span style="font-family:Verdana;"> 10.6) and diastolic dysfunction (aOR: 3.1;95% CI: 1.2 </span><span style="font-family:Verdana;">-</span><span style="font-family:;" "=""><span style="font-family:Verdana;"> 8.2) were independent factors associated with LV GLS. </span><b><span style="font-family:Verdana;">Conclusions:</span></b><span style="font-family:Verdana;"> Subclinical systolic dysfunction assessed by LV GLS impairment is frequent in diabetic patients. Further research should be carried out more extensively to integrate LV GLS in the type 2 diabetes patients’ routine follow up for a better prognostic outcome, especially in low-incomes countries.</span></span>展开更多
基金Project supported by the National Natural Science Foundation of China(Grant Nos.61888102,52272172,and 52102193)the Major Program of the National Natural Science Foundation of China(Grant No.92163206)+2 种基金the National Key Research and Development Program of China(Grant Nos.2021YFA1201501 and 2022YFA1204100)the Strategic Priority Research Program of the Chinese Academy of Sciences(Grant No.XDB30000000)the Fundamental Research Funds for the Central Universities.
文摘Discovery of materials using“bottom-up”or“top-down”approach is of great interest in materials science.Layered materials consisting of two-dimensional(2D)building blocks provide a good platform to explore new materials in this respect.In van der Waals(vdW)layered materials,these building blocks are charge neutral and can be isolated from their bulk phase(top-down),but usually grow on substrate.In ionic layered materials,they are charged and usually cannot exist independently but can serve as motifs to construct new materials(bottom-up).In this paper,we introduce our recently constructed databases for 2D material-substrate interface(2DMSI),and 2D charged building blocks.For 2DMSI database,we systematically build a workflow to predict appropriate substrates and their geometries at substrates,and construct the 2DMSI database.For the 2D charged building block database,1208 entries from bulk material database are identified.Information of crystal structure,valence state,source,dimension and so on is provided for each entry with a json format.We also show its application in designing and searching for new functional layered materials.The 2DMSI database,building block database,and designed layered materials are available in Science Data Bank at https://doi.org/10.57760/sciencedb.j00113.00188.
基金supported by the National Natural Science Foundation of China(U21A2078)Natural Science Foundation of Fujian Province(2020J06021,2019J01057,and 2020J01064)Scientific Research Funds of Huaqiao University.
文摘Quasi-2D perovskites have attracted tremendous interest for application as lightemission layers in light-emitting diodes(LEDs).However,the heterogeneous n phase and non-uniform distribution still severely limit the further development of quasi-2D perovskite LEDs(Pero-LEDs).Meanwhile,the increased defect density caused by the reduced dimension and grain size induces non-radiative recombination and further deteriorates the device performance.Here,we found that a series of molecules containing phosphoryl chloride functional groups have noticeable enhancement effects on the device performance of quasi-2D Pero-LEDs.Then,we studied the modification mechanism by focusing on the bis(2-oxo-3-oxazolidinyl)phosphinic chloride(BOPCl).It is concluded that the BOPCl can not only regulate the phase distribution by decreasing the crystallization rate but also remain in the grain boundaries and passivate the defects.As a result,the corresponding quasi-2D Pero-LEDs obtained a maximum external quantum efficiency(EQE_(max))of 20.82%and an average EQE(EQE_(ave))of around 20%on the optimal 50 devices,proving excellent reproducibility.Our work provides a new selection of molecular types for regulating the crystallization and passivating the defects of quasi-2D perovskite films.
基金the National Natural Science Foundation of China(Nos.11972365 and 12102458)。
文摘In this paper,we obtain Green’s functions of two-dimensional(2D)piezoelectric quasicrystal(PQC)in half-space and bimaterials.Based on the elastic theory of QCs,the Stroh formalism is used to derive the general solutions of displacements and stresses.Then,we obtain the analytical solutions of half-space and bimaterial Green’s functions.Besides,the interfacial Green’s function for bimaterials is also obtained in the analytical form.Before numerical studies,a comparative study is carried out to validate the present solutions.Typical numerical examples are performed to investigate the effects of multi-physics loadings such as the line force,the line dislocation,the line charge,and the phason line force.As a result,the coupling effect among the phonon field,the phason field,and the electric field is prominent,and the butterfly-shaped contours are characteristic in 2D PQCs.In addition,the changes of material parameters cause variations in physical quantities to a certain degree.
基金supported by a grant from R&D Program of the Korea Railroad Research Institute,Republic of Korea。
文摘Lithium-sulfur(Li-S)batteries are receiving increasing attention as one of the potential next-generation batteries,owing to their high energy densities and low cost.However,practical Li-S batteries with high energy densities are extremely hindered by the sulfur loss,low Coulombic efficiency,and short cycling life originating from the polysulfide(LiPS)shuttle.In this study,two-dimensional(2D)ZnCo_(2)O_(4) microsheets fabricated by a facile hydrothermal process are employed to modify the separator,for improving the electrochemical performances of Li-S cells.The resulting 2D Zn Co_(2)O_(4)-coated separator features a coating thickness of approximately 10 lm,high ionic conductivity of 1.8 m S/cm,and low mass loading of 0.2 mg/cm^(2).This 2D ZnCo_(2)O_(4)-coated separator effectively inhibits Li PS shuttle by a strong chemical interaction with Li PS as well as promotes the redox kinetics by Zn CO2O4-coated layers,as determined by X-ray photoelectron spectroscopy analysis,self-discharge,time-dependent permeation test,Li symmetric cell test,and Li2S nucleation analyses.Consequently,the Li-S batteries based on the 2D Zn Co_(2)O_(4)-coated separator exhibit a high initial discharge capacity of 1292.2 m Ah/g at 0.1 C.Moreover,they exhibit excellent long cycle stability at 1 and 2 C with capacity retention of 84%and 86%even after800 cycles,corresponding to a capacity fading rate of 0.020%and 0.016%per cycle,respectively.Effectively,these Li-S cells with a high sulfur loading at 5.3 mg/cm^(2) and low electrolyte concentration of 9 l L/mg deliver a high discharge capacity of 4.99 m Ah/cm^(2) after 200 cycles at 0.1 C.
文摘The authors introduce nonseparable scaling function interpolation and show that its approximation can provide similar convergence properties as scalar wavelet system. Several equivalent statements of accuracy of nonseparable scaling function are also given. In the numerical experiments, it appears that nonseparable scaling function interpolation has better convergence results than scalar wavelet systems in some cases.
文摘目的:探讨维生素D治疗新生儿感染性肺炎的效果及其对Toll样受体2(Toll-like receptor 2,TLR2)的影响。方法:选取2021年1月—2022年12月厦门医学院附属第二医院收治的85例新生儿感染性肺炎患儿。根据电脑编号单双差异随机将其分为试验组(42例)及参考组(43例)。参考组给予常规抗感染治疗,试验组在参考组基础上给予维生素D。比较两组临床疗效、时间指标,治疗前1 d及治疗7 d后炎症因子、免疫功能。结果:试验组治疗总有效率高于参考组,差异有统计学意义(P<0.05)。试验组病原学检查转阴时间、临床症状消失时间早于参考组,住院时间短于参考组,差异有统计学意义(P<0.05)。治疗7 d后,试验组TLR2及白细胞介素-6(interleukin-6,IL-6)、白细胞介素-8(interleukin-8,IL-8)水平均低于参考组,差异有统计学意义(P<0.05)。治疗7 d后,两组CD3^(+)、CD4^(+)、红细胞C3b受体花环率(adherence rate of complement 3b-receptor on the surface of red blood cell,RBC-C3bR)均高于治疗前1 d,试验组高于参考组,两组CD8^(+)、红细胞免疫复合物花环率(immune complex adherence rate of red blood cell,RBC-ICR)均低于治疗前1 d,试验组低于参考组,差异有统计学意义(P<0.05)。结论:维生素D治疗新生儿感染性肺炎的效果较佳,且能减轻炎症反应,改善免疫功能。
文摘<strong>Background:</strong><span style="font-family:Verdana;"> Heart failure is the commonest cardiovascular complication in type 2 diabetes mellitus. However, subclinical left ventricular dysfunction can’t be detected using 2D echocardiography which </span><span style="font-family:Verdana;">is </span><span style="font-family:;" "=""><span style="font-family:Verdana;">routinely used for cardiac evaluation of diabetic patients. We aimed to determine the prevalence and factors associated to left ventricular global longitudinal strain (LV GLS) impairment in type 2 diabetes Cameroonians patients. </span><b><span style="font-family:Verdana;">Methods:</span></b><span style="font-family:Verdana;"> We conducted a cross-sectional study from January 2019 to June 2019, including type 2 diabetes patients with preserved left ventricle ejection fraction. Clinical and echocardiographic data were collected, and LV GLS was assessed using speckle tracking technique, a value ≤</span></span><span style="font-family:Verdana;"> -</span><span style="font-family:;" "=""><span style="font-family:Verdana;">16% been considered as normal value. </span><b><span style="font-family:Verdana;">Results:</span></b><span style="font-family:Verdana;"> We recruited 95 patients, with a mean age of 57.4 ± 11.8 years old and median diabetes duration of 5 [2 </span></span><span style="font-family:Verdana;">-</span><span style="font-family:Verdana;"> 12] years. Echocardiographic evaluation found 56.3% of left ventricle remodelling, 51.6% of left ventricle diastolic dysfunction and mean left ventricle ejection of 63.3</span><span style="font-family:Verdana;">%</span><span style="font-family:Verdana;"> ± 6.6%. LV GLS impairment was present in 43.2% (95% CI: 32.6 </span><span style="font-family:Verdana;">-</span><span style="font-family:Verdana;"> 53.7) of the participants. After adjustment to all significantly associated factors, Obesity (aOR: 4;95% CI: 1.5 </span><span style="font-family:Verdana;">-</span><span style="font-family:Verdana;"> 10.6) and diastolic dysfunction (aOR: 3.1;95% CI: 1.2 </span><span style="font-family:Verdana;">-</span><span style="font-family:;" "=""><span style="font-family:Verdana;"> 8.2) were independent factors associated with LV GLS. </span><b><span style="font-family:Verdana;">Conclusions:</span></b><span style="font-family:Verdana;"> Subclinical systolic dysfunction assessed by LV GLS impairment is frequent in diabetic patients. Further research should be carried out more extensively to integrate LV GLS in the type 2 diabetes patients’ routine follow up for a better prognostic outcome, especially in low-incomes countries.</span></span>
