Active and poisoning-resistant Ru-based electrocatalysts for the hydrogen oxidation reaction(HOR)are designed and fabricated by integrating Cu/Ru dual single atoms and alloy CuRu nanoparticles(N-(CuRu)_(NP+SA)@NC)thro...Active and poisoning-resistant Ru-based electrocatalysts for the hydrogen oxidation reaction(HOR)are designed and fabricated by integrating Cu/Ru dual single atoms and alloy CuRu nanoparticles(N-(CuRu)_(NP+SA)@NC)through a strategy involving weak chemical reduction and ammonia-assisted gas-phase nitridation.The resultant N-(CuRu)_(NP+SA)@NC electrocatalysts feature nitrogen atoms coordinated to both Cu and Ru metal atoms via strong N-metal interactions.Density functional theory calculations revealed that alloyed CuRu nanoparticles and monodispersed Cu atoms are vital for altering the electronic configuration of the host Ru elements.This finely tuned structure enhanced the adsorption of H and OH and promoted CO oxidation over the N-(CuRu)_(NP+SA)@NC electrocatalyst,resulting in high alkaline HOR activity,as evidenced by the higher exchange current density of 3.74 mA cm^(-2)and high mass activity of 3.28 mAμg_(Ru)^(-1),which are far superior to those of most Ru-based catalysts reported to date.Moreover,the N-(CuRu)_(NP+SA)@NC electrocatalysts are resistant to CO poisoning and can be used at a high concentration of 1000 ppm CO with no distinct decay in the activity,in stark contrast to the commercial Pt/C catalyst under the same conditions.展开更多
BA_(2)(MA)_(n-1)Pb_nI_(3n+1)series low-dimensional(2D)perovskites have been widely investigated for their re markable environmental stability,but still suffer the poor light absorption and disordered phase distri buti...BA_(2)(MA)_(n-1)Pb_nI_(3n+1)series low-dimensional(2D)perovskites have been widely investigated for their re markable environmental stability,but still suffer the poor light absorption and disordered phase distri bution,hindering their practical applications.In this work,we combine the introduction of FA and the addition of PbCl_(2)to optimize the film quality,strengthen the light absorption,regulate internal phase distribution,and promote carrier transport inside 2D perovskite films.The incorporation of FA promote sufficient light absorption and improve the film crystallinity.Furthermore,the addition of Pb Cl_(2)elimi nates the low n phase(n=1)and suppresses the forming of the low n phase of n=2,enhancing the film conductivity and diminishing carrier recombination.The synergistic of A-site cation engineering and phase manipulation achieves a high efficiency of 16.48%.Importantly,the synergistic prepared perovskite film does not show any changes after 60 days in the air with an average humidity of 57%±3%,and the corresponding solar cell maintains 85%of the original efficiency after more than 800 h,demonstrating remarkable environmental stability.The results indicate that the synergistic of A-site cation engineering and phase manipulation is promising for producing superior efficiency,along with satisfying humidity stability.展开更多
The major solving ways for the material wear are surface modification and lubrication. Currently, the researches at home and abroad are all limited to the single study of either nano-lubricating oil additive or electr...The major solving ways for the material wear are surface modification and lubrication. Currently, the researches at home and abroad are all limited to the single study of either nano-lubricating oil additive or electroless deposited coating. The surface coating has high hardness and high wear resistance, however, the friction reduction performance of the coating with high hardness is not good, the thickness of the coating is limited, and the coating can not regenerate after wearing. The nano-lubricating additives have good tribological performance and self-repair function, but under heavy load, the self-repair rate to the worn surface with the nano-additives is smaller than the wearing rate of the friction pair. To solve the above problems, the Ni-W-P alloy coating and deposition process with excellent anti-wear, and suitable for industrial application were developed, the optimum bath composition and process can be obtained by studying the influence of the bath composition, temperature and PH value to the deposition rate and the plating solution stability. The tribological properties as well as anti-wear and friction reduction mechanism of wear self-repair nano-ceramic lubricating additives are also studied. The ring-block abrasion testing machine and energy dispersive spectrometer are used to explore the internal relation between the coating and the nano-lubricating oil additives, and the tribology mechanism, to seek the synergetic effect between the two. The test results show that the wear resistance of Ni-W-P alloy coating （with heat treatment and in oil with nano-ceramic additives） has increased hundreds times than 45 steel as the metal substrate in basic oil, the friction reduction performance is improved. This research breaks through the bottleneck of previous separate research of the above-mentioned two methods, and explores the combination use of the two methods in industrial field.展开更多
Orbital hybridization plays a crucial role in catalytic processes,yet elucidating its mechanism remains a significant challenge.Here,we have developed a strategy for the formation of Yb-C bond by unconventional p-d or...Orbital hybridization plays a crucial role in catalytic processes,yet elucidating its mechanism remains a significant challenge.Here,we have developed a strategy for the formation of Yb-C bond by unconventional p-d orbital hybridization,which induced carbon nitride modified by rare-earth metal element Yb.The optimal sample exhibits catalytic performance 11.2 times greater than that of g-C_(3)N_(4)with N vacancies(NvCN).Yb-C bond and N vacancies reduced the energy barrier and optimized the rate-determining step(*COO+*H→*CO+*OH).Additionally,the intense Yb-C interaction created a specific electrons bridge,which accelerated the transfer rate of electrons on the photocatalytic surface.Next,the CO_(2) conversion reaction mechanism was studied by in situ infrared spectroscopy and theoretical calculations,and the unconventional p-d orbital hybridization contributed to the generation of vital intermediate*CO.This study provides a theoretical basis for designing single-atom photocatalysts for the reduction of CO_(2).展开更多
Marine pollution poses a critical threat to biodiversity.The synergistic effects of microplastics,specifically high-density polyethylene(HDPE),combined with benzo[a]pyrene(B[a]P)and heavy metals,on the physiology and ...Marine pollution poses a critical threat to biodiversity.The synergistic effects of microplastics,specifically high-density polyethylene(HDPE),combined with benzo[a]pyrene(B[a]P)and heavy metals,on the physiology and feeding behavior of the seahorse,Hippocampus erectus were studied.The growth parameters,pollutant bioaccumulation,enzymatic response,and feeding dynamics were extensively analyzed.Seahorses exposed to microplastics-borne B[a]P and heavy metals exhibited notable reductions in body length and weight,as well as in survival rates,indicating severe stress from these contaminants.The accumulation of pollutant particularly B[a]P in seahorse exceeded China’s national regulatory limit of 5μg/kg,and the B[a]P accumulation in seahorses was obviously aided by HDPE microplastics,posing a risk to marine organisms and human health via the food chain.The adaptive response of the seahorses was evident shown in the elevation of antioxidant enzyme activities,which is a biological mechanism to mitigate oxidative stress induced by the pollutants.However,this physiological adaptation comes at a cost,as evidenced by marked changes in the feeding behavior.Results show that the efficiency and frequency of feeding were greatly reduced,indicating a heavy impact on the ecological role and survival of this marine creature in polluted habitats.This research offers a crucial perspective on the compound threats of microplastics and associated pollutants in marine ecosystems.It highlights the urgent need develop comprehensive strategies to address these environmental issues.The findings are an important contribution to ecotoxicology,providing a deeper understanding of how microplastics act as vectors for other contaminants and their profound effects on marine life,especially species like seahorses.This study calls for action to strengthen environmental policies and practices aimed at mitigating the impact of marine pollution.展开更多
The coating and deposition process with excellent anti wear and suitable for industrial application were developed, and the optimum bath composition and process were obtained by studying the influence of the bath comp...The coating and deposition process with excellent anti wear and suitable for industrial application were developed, and the optimum bath composition and process were obtained by studying the influence of the bath composition, temperature and pH value on the deposition rate and the plating solution stability. Moreover, the tribological properties of nano-Cu lubricating additives and electroless deposited Ni-W-P coating as well as their synergistic effect are researched using ring-block abrasion testing machine and energy dispersive spectrometer. Research results show that Ni-W-P alloy coating and nano-Cu lubricating additive have excellent synergistic effect, e g, the wear resistance of Ni-W-P alloy coating （with heat treatment and the oil with nano-Cu additives） has increased hundreds times than 45 steel as the metal substrate with the basic oil, and zero wear is achieved, which breaks through the bottleneck of previous separate research of the above-mentioned two aspects.展开更多
We have analyzed the photorefractive（PR） effect of a polymer composite was reported which combines a novel bi-functional poly（N-vinyl）-3-[p-nitrophenylazo]carbazolyl（PVNPAK） and 2,4,7-trinitro-9-fluorenone（TNF...We have analyzed the photorefractive（PR） effect of a polymer composite was reported which combines a novel bi-functional poly（N-vinyl）-3-[p-nitrophenylazo]carbazolyl（PVNPAK） and 2,4,7-trinitro-9-fluorenone（TNF）. PVNPAK was synthesized by a post-azo-coupling reaction, with an azo derivative as the electrooptic chromophore and carbazolyl as photoconductive moiety. The asymmetric two-beam coupling gain of 13.9 cm-1 and diffraction efficiency of 1.2% for poled polymer film fabricated using a corona poling are obtained at the wavelength of 647.1 nm, confirming photorefractivity. We interpreted this result as the orientational enhancement, in which the spatial charge field may enhance the modulated orientation of the azobenzen chromophore. It is unexpected that the photorefractive gain of 9.5 cm-1 for the unpoled polymer film also was observed without external field in two-beam coupling（TBC） experiment. This phenomenon is attributed to a light-induced orientational grating when the azobenzene groups are illuminated by polarized light.展开更多
Objective Loss-of-function mutation of p53,a tumor suppressor gene,is an important mechanism for the development of human cancers. In this study we tried to transfect p53N15-based fusion peptide into H1299,a lung canc...Objective Loss-of-function mutation of p53,a tumor suppressor gene,is an important mechanism for the development of human cancers. In this study we tried to transfect p53N15-based fusion peptide into H1299,a lung cancer cell line,and evaluate the anti-tumor effects of the fusion peptide. Methods Adeno-associated virus (AAV) vectors were used for transfecting p53N15 fusion peptide into p53-null lung adenocarcinoma H1299 cells.展开更多
文摘Active and poisoning-resistant Ru-based electrocatalysts for the hydrogen oxidation reaction(HOR)are designed and fabricated by integrating Cu/Ru dual single atoms and alloy CuRu nanoparticles(N-(CuRu)_(NP+SA)@NC)through a strategy involving weak chemical reduction and ammonia-assisted gas-phase nitridation.The resultant N-(CuRu)_(NP+SA)@NC electrocatalysts feature nitrogen atoms coordinated to both Cu and Ru metal atoms via strong N-metal interactions.Density functional theory calculations revealed that alloyed CuRu nanoparticles and monodispersed Cu atoms are vital for altering the electronic configuration of the host Ru elements.This finely tuned structure enhanced the adsorption of H and OH and promoted CO oxidation over the N-(CuRu)_(NP+SA)@NC electrocatalyst,resulting in high alkaline HOR activity,as evidenced by the higher exchange current density of 3.74 mA cm^(-2)and high mass activity of 3.28 mAμg_(Ru)^(-1),which are far superior to those of most Ru-based catalysts reported to date.Moreover,the N-(CuRu)_(NP+SA)@NC electrocatalysts are resistant to CO poisoning and can be used at a high concentration of 1000 ppm CO with no distinct decay in the activity,in stark contrast to the commercial Pt/C catalyst under the same conditions.
基金supported by the Chengdu Science and Technology Program(No.2021GH0200032HZ)Sichuan Engineering Technology Research Center of Basalt Fiber Composites Development and Application(No.2022SCXWYXWFC006)Natural Science Foundation of Sichuan Province(No.2022NSFSC0356)。
文摘BA_(2)(MA)_(n-1)Pb_nI_(3n+1)series low-dimensional(2D)perovskites have been widely investigated for their re markable environmental stability,but still suffer the poor light absorption and disordered phase distri bution,hindering their practical applications.In this work,we combine the introduction of FA and the addition of PbCl_(2)to optimize the film quality,strengthen the light absorption,regulate internal phase distribution,and promote carrier transport inside 2D perovskite films.The incorporation of FA promote sufficient light absorption and improve the film crystallinity.Furthermore,the addition of Pb Cl_(2)elimi nates the low n phase(n=1)and suppresses the forming of the low n phase of n=2,enhancing the film conductivity and diminishing carrier recombination.The synergistic of A-site cation engineering and phase manipulation achieves a high efficiency of 16.48%.Importantly,the synergistic prepared perovskite film does not show any changes after 60 days in the air with an average humidity of 57%±3%,and the corresponding solar cell maintains 85%of the original efficiency after more than 800 h,demonstrating remarkable environmental stability.The results indicate that the synergistic of A-site cation engineering and phase manipulation is promising for producing superior efficiency,along with satisfying humidity stability.
文摘The major solving ways for the material wear are surface modification and lubrication. Currently, the researches at home and abroad are all limited to the single study of either nano-lubricating oil additive or electroless deposited coating. The surface coating has high hardness and high wear resistance, however, the friction reduction performance of the coating with high hardness is not good, the thickness of the coating is limited, and the coating can not regenerate after wearing. The nano-lubricating additives have good tribological performance and self-repair function, but under heavy load, the self-repair rate to the worn surface with the nano-additives is smaller than the wearing rate of the friction pair. To solve the above problems, the Ni-W-P alloy coating and deposition process with excellent anti-wear, and suitable for industrial application were developed, the optimum bath composition and process can be obtained by studying the influence of the bath composition, temperature and PH value to the deposition rate and the plating solution stability. The tribological properties as well as anti-wear and friction reduction mechanism of wear self-repair nano-ceramic lubricating additives are also studied. The ring-block abrasion testing machine and energy dispersive spectrometer are used to explore the internal relation between the coating and the nano-lubricating oil additives, and the tribology mechanism, to seek the synergetic effect between the two. The test results show that the wear resistance of Ni-W-P alloy coating （with heat treatment and in oil with nano-ceramic additives） has increased hundreds times than 45 steel as the metal substrate in basic oil, the friction reduction performance is improved. This research breaks through the bottleneck of previous separate research of the above-mentioned two methods, and explores the combination use of the two methods in industrial field.
基金financially supported by the National Natural Science Foundation of China(No.52370109)Guangdong Province Scientific Research Platform Project(Nos.2023ZDZX4052,2022ZDZX4046)+3 种基金Shaoguan Science and Technology Projects(No.230616088031998)High Level Talents Introduction Project of"Pearl River Talent Plan"in Guangdong Province(No.2019CX01L308)the Support Scheme of Guangzhou for Leading Talents in Innovation and Entrepreneurship Funding(No.2016015)the Science and Technology Research Program of Chongqing Municipal Education Commission of China(No.KJZDM202400802)
文摘Orbital hybridization plays a crucial role in catalytic processes,yet elucidating its mechanism remains a significant challenge.Here,we have developed a strategy for the formation of Yb-C bond by unconventional p-d orbital hybridization,which induced carbon nitride modified by rare-earth metal element Yb.The optimal sample exhibits catalytic performance 11.2 times greater than that of g-C_(3)N_(4)with N vacancies(NvCN).Yb-C bond and N vacancies reduced the energy barrier and optimized the rate-determining step(*COO+*H→*CO+*OH).Additionally,the intense Yb-C interaction created a specific electrons bridge,which accelerated the transfer rate of electrons on the photocatalytic surface.Next,the CO_(2) conversion reaction mechanism was studied by in situ infrared spectroscopy and theoretical calculations,and the unconventional p-d orbital hybridization contributed to the generation of vital intermediate*CO.This study provides a theoretical basis for designing single-atom photocatalysts for the reduction of CO_(2).
基金Supported by the Marine Economic Development Project(No.GDNRC[2022]36)the National Key Research and Development Program of China(No.2018YFD0900206)the Tianjin Science and Technology Program Project(No.21YDTPJC00340)。
文摘Marine pollution poses a critical threat to biodiversity.The synergistic effects of microplastics,specifically high-density polyethylene(HDPE),combined with benzo[a]pyrene(B[a]P)and heavy metals,on the physiology and feeding behavior of the seahorse,Hippocampus erectus were studied.The growth parameters,pollutant bioaccumulation,enzymatic response,and feeding dynamics were extensively analyzed.Seahorses exposed to microplastics-borne B[a]P and heavy metals exhibited notable reductions in body length and weight,as well as in survival rates,indicating severe stress from these contaminants.The accumulation of pollutant particularly B[a]P in seahorse exceeded China’s national regulatory limit of 5μg/kg,and the B[a]P accumulation in seahorses was obviously aided by HDPE microplastics,posing a risk to marine organisms and human health via the food chain.The adaptive response of the seahorses was evident shown in the elevation of antioxidant enzyme activities,which is a biological mechanism to mitigate oxidative stress induced by the pollutants.However,this physiological adaptation comes at a cost,as evidenced by marked changes in the feeding behavior.Results show that the efficiency and frequency of feeding were greatly reduced,indicating a heavy impact on the ecological role and survival of this marine creature in polluted habitats.This research offers a crucial perspective on the compound threats of microplastics and associated pollutants in marine ecosystems.It highlights the urgent need develop comprehensive strategies to address these environmental issues.The findings are an important contribution to ecotoxicology,providing a deeper understanding of how microplastics act as vectors for other contaminants and their profound effects on marine life,especially species like seahorses.This study calls for action to strengthen environmental policies and practices aimed at mitigating the impact of marine pollution.
文摘The coating and deposition process with excellent anti wear and suitable for industrial application were developed, and the optimum bath composition and process were obtained by studying the influence of the bath composition, temperature and pH value on the deposition rate and the plating solution stability. Moreover, the tribological properties of nano-Cu lubricating additives and electroless deposited Ni-W-P coating as well as their synergistic effect are researched using ring-block abrasion testing machine and energy dispersive spectrometer. Research results show that Ni-W-P alloy coating and nano-Cu lubricating additive have excellent synergistic effect, e g, the wear resistance of Ni-W-P alloy coating （with heat treatment and the oil with nano-Cu additives） has increased hundreds times than 45 steel as the metal substrate with the basic oil, and zero wear is achieved, which breaks through the bottleneck of previous separate research of the above-mentioned two aspects.
基金Funded by the National Natural Science Foundation of China(No.51303115)
文摘We have analyzed the photorefractive（PR） effect of a polymer composite was reported which combines a novel bi-functional poly（N-vinyl）-3-[p-nitrophenylazo]carbazolyl（PVNPAK） and 2,4,7-trinitro-9-fluorenone（TNF）. PVNPAK was synthesized by a post-azo-coupling reaction, with an azo derivative as the electrooptic chromophore and carbazolyl as photoconductive moiety. The asymmetric two-beam coupling gain of 13.9 cm-1 and diffraction efficiency of 1.2% for poled polymer film fabricated using a corona poling are obtained at the wavelength of 647.1 nm, confirming photorefractivity. We interpreted this result as the orientational enhancement, in which the spatial charge field may enhance the modulated orientation of the azobenzen chromophore. It is unexpected that the photorefractive gain of 9.5 cm-1 for the unpoled polymer film also was observed without external field in two-beam coupling（TBC） experiment. This phenomenon is attributed to a light-induced orientational grating when the azobenzene groups are illuminated by polarized light.
文摘Objective Loss-of-function mutation of p53,a tumor suppressor gene,is an important mechanism for the development of human cancers. In this study we tried to transfect p53N15-based fusion peptide into H1299,a lung cancer cell line,and evaluate the anti-tumor effects of the fusion peptide. Methods Adeno-associated virus (AAV) vectors were used for transfecting p53N15 fusion peptide into p53-null lung adenocarcinoma H1299 cells.
