Metal-free g-C_3N_4 is widely used in photocatalytic reactions owing to its suitable band structure.However, it has low specific surface area and insufficient absorbance for visible light, and its photoexcited carrier...Metal-free g-C_3N_4 is widely used in photocatalytic reactions owing to its suitable band structure.However, it has low specific surface area and insufficient absorbance for visible light, and its photoexcited carriers have high recombination rates. In this study, the 3 D macropore C-vacancy g-C_3N_4 was prepared through a facile one-step route. Polymethylmethacrylate is used as a template to increase the surface reaction sites of g-C_3N_4 and extend its visible-light range. Compared to unmodified g-C_3N_4, the H2 production and CO_2 reduction rates of the fabricated g-C_3N_4 significantly improved. The special pore structure significantly improved the light utilization efficiency of g-C_3N_4 and increased the number of surface-active sites. The introduction of C-vacancy extended the absorption band of visible-light and suppressed the carrier recombination. The newly developed synthesis strategy can improve solar energy conversion efficiency and potentially modifies g-C_3N_4.展开更多
Sepiolite(ST) was used as a supporting matrix in compiste phase change materials(PCMs) due to its unique microstructure, good thermal stability, and other raw material advantages. In this paper, microwave acid treatme...Sepiolite(ST) was used as a supporting matrix in compiste phase change materials(PCMs) due to its unique microstructure, good thermal stability, and other raw material advantages. In this paper, microwave acid treatment were innovatively used for the modification of sepiolite. The modified sepiolite(ST_(m)) obtained in different hydrochloric acid concentrations(0.25, 0.5, 0.75, and 1.0 mol·L^(-1)) was added to stearic acid(SA) via vacuum impregnation method. The thermophysical properties of the composites were changed by varying the hydrochloric acid concentration. The SA-ST_(m0.5)obtained by microwave acid treatment at 0.5 mol·L^(-1)hydrochloric acid concentration showed a higher loading capacity(82.63%) than other composites according to the differential scanning calorimeter(DSC) analysis. The melting and freezing enthalpies of SA-ST_(m0.5)were of 152.30 and 148.90 J·g^(-1), respectively. The thermal conductivity of SA-ST_(m0.5)was as high as 1.52 times that of pure SA. In addition, the crystal structure, surface morphology, and microporous structure of ST_(m)were studied, and the mechanism of SAST_(m0.5)performance enhancement was further revealed by Brunauere Emmett Teller(BET) analysis. Leakage experiment showed that SAST_(m0.5)had a good morphological stability. These results demostrate that SA-ST_(m0.5)has a potential application in thermal energy storage.展开更多
In recent years,many studies have investigated the correlations between Parkinson's disease(PD)and vitamin D status,but the conclusion remains elusive.The present review focuses on the associations between PD and ...In recent years,many studies have investigated the correlations between Parkinson's disease(PD)and vitamin D status,but the conclusion remains elusive.The present review focuses on the associations between PD and serum vitamin D levels by reviewing studies on the associations of PD with serum vitamin D levels and vitamin D receptor(VDR)gene polymorphisms from PubMed,Web of Science,Cochrane Library,and Embase databases.We found that PD patients have lower vitamin D levels than healthy controls and that the vitamin D concentrations are negatively correlated with PD risk and severity.Furthermore,higher vitamin D concentrations are linked to better cognitive function and mood in PD patients.Findings on the relationship between VDR gene polymorphisms and the risk of PD are inconsistent,but the Fokl(C/M)polymorphism is significantly linked with PD.The occurrence of Fokl(CT)gene polymorphism may influence the risk,severity,and cognitive ability of PD patients,while also possibly influencing the effect of Vitamin D3 supplementation in PD patients.In view of the neuroprotective effects of vitamin D and the close association between vitamin D and dopaminergic neurotransmission,interventional prospective studies on vitamin D supplementation in PD patients should be conducted in the future.展开更多
基金financial support from the National Natural Science Foundation of China (51862023, 51662030, 21868016)the Natural Science Foundation of Jiangxi Province (20171BAB206014, 2018BCD40004)。
文摘Metal-free g-C_3N_4 is widely used in photocatalytic reactions owing to its suitable band structure.However, it has low specific surface area and insufficient absorbance for visible light, and its photoexcited carriers have high recombination rates. In this study, the 3 D macropore C-vacancy g-C_3N_4 was prepared through a facile one-step route. Polymethylmethacrylate is used as a template to increase the surface reaction sites of g-C_3N_4 and extend its visible-light range. Compared to unmodified g-C_3N_4, the H2 production and CO_2 reduction rates of the fabricated g-C_3N_4 significantly improved. The special pore structure significantly improved the light utilization efficiency of g-C_3N_4 and increased the number of surface-active sites. The introduction of C-vacancy extended the absorption band of visible-light and suppressed the carrier recombination. The newly developed synthesis strategy can improve solar energy conversion efficiency and potentially modifies g-C_3N_4.
基金financially supported by the National Natural Science Foundation of China (No.52274252)the Special Fund for the Construction of Innovative Provinces in Hunan Province,China (Nos.2020RC3038 and 2022WK4004)the Changsha City Fund for Distinguished and Innovative Young Scholars,China (No.kq1802007)。
文摘Sepiolite(ST) was used as a supporting matrix in compiste phase change materials(PCMs) due to its unique microstructure, good thermal stability, and other raw material advantages. In this paper, microwave acid treatment were innovatively used for the modification of sepiolite. The modified sepiolite(ST_(m)) obtained in different hydrochloric acid concentrations(0.25, 0.5, 0.75, and 1.0 mol·L^(-1)) was added to stearic acid(SA) via vacuum impregnation method. The thermophysical properties of the composites were changed by varying the hydrochloric acid concentration. The SA-ST_(m0.5)obtained by microwave acid treatment at 0.5 mol·L^(-1)hydrochloric acid concentration showed a higher loading capacity(82.63%) than other composites according to the differential scanning calorimeter(DSC) analysis. The melting and freezing enthalpies of SA-ST_(m0.5)were of 152.30 and 148.90 J·g^(-1), respectively. The thermal conductivity of SA-ST_(m0.5)was as high as 1.52 times that of pure SA. In addition, the crystal structure, surface morphology, and microporous structure of ST_(m)were studied, and the mechanism of SAST_(m0.5)performance enhancement was further revealed by Brunauere Emmett Teller(BET) analysis. Leakage experiment showed that SAST_(m0.5)had a good morphological stability. These results demostrate that SA-ST_(m0.5)has a potential application in thermal energy storage.
基金The authors of this review were supported by the National Natural Science Foundation of China(81971201)the National Science Foundation of Hunan Province(2019J40450).
文摘In recent years,many studies have investigated the correlations between Parkinson's disease(PD)and vitamin D status,but the conclusion remains elusive.The present review focuses on the associations between PD and serum vitamin D levels by reviewing studies on the associations of PD with serum vitamin D levels and vitamin D receptor(VDR)gene polymorphisms from PubMed,Web of Science,Cochrane Library,and Embase databases.We found that PD patients have lower vitamin D levels than healthy controls and that the vitamin D concentrations are negatively correlated with PD risk and severity.Furthermore,higher vitamin D concentrations are linked to better cognitive function and mood in PD patients.Findings on the relationship between VDR gene polymorphisms and the risk of PD are inconsistent,but the Fokl(C/M)polymorphism is significantly linked with PD.The occurrence of Fokl(CT)gene polymorphism may influence the risk,severity,and cognitive ability of PD patients,while also possibly influencing the effect of Vitamin D3 supplementation in PD patients.In view of the neuroprotective effects of vitamin D and the close association between vitamin D and dopaminergic neurotransmission,interventional prospective studies on vitamin D supplementation in PD patients should be conducted in the future.