In the field of quantum error mitigation,most current research separately addresses quantum gate noise mitigation and measurement noise mitigation.However,due to the typically high complexity of measurement noise miti...In the field of quantum error mitigation,most current research separately addresses quantum gate noise mitigation and measurement noise mitigation.However,due to the typically high complexity of measurement noise mitigation methods,such as those based on estimating response matrices,the overall complexity of noise mitigation schemes increases when combining measurement noise mitigation with other quantum gate noise mitigation approaches.This paper proposes a low-complexity quantum error mitigation scheme that jointly mitigates quantum gate and measurement noise,specifically when measurement noise manifests as an amplitude damping channel.The proposed scheme requires estimating only three parameters to jointly mitigate both types of noise,whereas the zero-noise extrapolation method enhanced by response matrix estimation requires estimating at least six parameters under the same conditions.展开更多
Dear Editor,In this study,we re-identified the hosts of cyanophage PP.Twenty-three candidate algal strains were tested,and the results indicated that seven strains belonging to Plectonema and Phormidium are the hosts ...Dear Editor,In this study,we re-identified the hosts of cyanophage PP.Twenty-three candidate algal strains were tested,and the results indicated that seven strains belonging to Plectonema and Phormidium are the hosts of cyanophage PP,including two previously reported filamentous cyanobacteria,Plectonema boryanum and Phormidium展开更多
The increasing occurrence of Microcystis blooms is of great concern to public health and ecosystem due to the potential hepatotoxic microcystins （MCs） produced by these colonial cyanobacteria. In order to interpret ...The increasing occurrence of Microcystis blooms is of great concern to public health and ecosystem due to the potential hepatotoxic microcystins （MCs） produced by these colonial cyanobacteria. In order to interpret the relationships between variations of Microcyst/s morphospedes and extracellular MC concentrations, the seasonal dynamics of phytoplankton community composition, MC concentrations, and environmental parameters were monitored monthly from August, 2009 to July, 2010. The results indicated that Microcystis dominated total phytoplankton abundance from May to December （96%--99% of total biovolume）, with toxic Microcystis viridis and non-toxic Microcystis wesenbergii dominating after July （constituting 65%- 95% of the Microcystis population）, followed by M. viridis as the sole dominant species from November to January （49%--93%）. Correlation analysis revealed that water temperature and nutrient were the most important variables accounting for the occurrence ofM. wesenbergii, while the dominance ofM. viridis was related with nitrite and nitrate. The relatively low content of MCs was explained by the association with a large proportion of M. viriclis and M. wesenbergii, small colony size of Microcystis populations, and low water temperature, pH and dissolved oxygen. The extracellular MC （mean of 0.5 ± 0.2 μg/L） of water samples analyzed by enzyme-linked immunosorbent assay （ELISA） demonstrated the low concentrations of MC in Dianchi Lake which implied the low potential risk for human health in the basin. The survey provides the first whole lake study of the occurrence and seasonal variability of Microcyst/s population and展开更多
Owing to the exorbitant overpotential and serious carrier recombination of graphitic carbon nitride(gC_(3)N_(4)),noble metal(NM)is usually served as the H_(2)evolution co-catalyst.Although the NM(such as Pt)nanopartic...Owing to the exorbitant overpotential and serious carrier recombination of graphitic carbon nitride(gC_(3)N_(4)),noble metal(NM)is usually served as the H_(2)evolution co-catalyst.Although the NM(such as Pt)nanoparticles can reduce the H_(2)evolution overpotential,the weak van der Waals interaction between Pt and g-C_(3)N_(4)makes against the charge transfer.Herein,the solvothermal method is developed to achieve semi-chemical interaction between Pt and g-C_(3)N_(4)nanotube(Pt-CNNT)for fast charge transfer.Moreover,the generated in-plane homojunction of CNNT can accelerate charge separation and restrain recombination.Meanwhile,the metallic Pt is an excellent H_(2)evolution co-catalyst.Photo/electrochemical tests verify that the semi-chemical interaction can improve photogenerated charge separation and transferability of CNNT.As a result,the photocatalytic H_(2)evolution turnover frequency(TOF)of Pt-CNNT under visible light irradiation reaches up to 918 h^(-1),which is one of the highest in the g-C_(3)N_(4)-based photocatalysts.This work provides a new idea to improve the charge transfer for efficient photocatalytic H_(2)evolution.展开更多
To learn the relationship between sunlight intensity and cyanobacterial proliferations for the further control of the heavy blooms, enclosure experiment were conducted in Meiliang Bay, Lake Taihu by regulating the nat...To learn the relationship between sunlight intensity and cyanobacterial proliferations for the further control of the heavy blooms, enclosure experiment were conducted in Meiliang Bay, Lake Taihu by regulating the natural light intensities with different shading ratio （0% （full sunlight）, 10%, 25%, 50% and 75% of original natural sunlight intensities） from September to November in 2010. The results indicated that phytoplankton biomass （mean） decreased significantly when the shading ratios reached 50% or more. Higher shading ratios （e.g. 75%） were very efficient in controlling the average and total cyanobacterialbloom biomass, while 50% shading ratio was proven very effective either in controlling the peak value of phytoplankton biomass or postponing the occurrence of cyanobacterial blooms in Lake Talhu. In addition, phytoplankton composition and photosynthesis efficiency were also affected by altering the shading ratios, and in turn, they might also act on phytoplankton growth. Based on the results from the present study, intermediate shading strategies such as regulation of water level or turbidity through the hydrology regulations would probably be an effective and efficient method in controlling cyanobacterial blooms in large and shallow lakes.展开更多
[Objectives]This study was conducted to investigate the effects of different heavy metal stresses on seed germination,in order to provide a theoretical basis for phytoremediation of soil heavy metal pollution.[Methods...[Objectives]This study was conducted to investigate the effects of different heavy metal stresses on seed germination,in order to provide a theoretical basis for phytoremediation of soil heavy metal pollution.[Methods]With the seeds of A.julibrissin as an experimental material,the germination test of A.julibrissin seeds under different concentrations of Cu^(2+),Zn^(2+) and Pb^(2+) was carried out.The germination potential,germination rate,germination index,radicle length,embryo length and other indexes were measured.[Results]①Different heavy metals had different effects on the germination of A.julibrissin seeds.Low concentrations of Cu^(2+),Zn^(2+) and Pb^(2+) stresses had certain promotion effects on the germination of A.julibrissin seeds,but high concentrations of Cu^(2+),Zn^(2+),Pb^(2+) stresses had obvious inhibitory effects on the germination of A.julibrissin seeds.②There were obvious differences in the tolerance of A.julibrissin seeds to different metal ion stresses.According to the comparison of the average values of membership functions,the order of their tolerance to different heavy metal ions was:Zn^(2+)>Cu^(2+)>Pb^(2+).[Conclusions]In the case of light pollution,the germination of A.julibrissin seeds was not inhibited,and the use of this plant for the remediation of lightly contaminated soil with heavy metals can also be considered.展开更多
In this paper, a method for predicting the position of towline is presented. The location of the finite node is determined by installing fixed spaced attitude sensors in towline arrays, then the appropriate objective ...In this paper, a method for predicting the position of towline is presented. The location of the finite node is determined by installing fixed spaced attitude sensors in towline arrays, then the appropriate objective functions are selected for water depth profile and course profile respectively, and the interpolation fitting method is combined with the determined predicted positions. Through the hydrodynamic analysis of the existing towing cable’s underwater motion, the position of the towing cable under the steady state motion is obtained as the reference basis, and two methods are put forward, which are improved spline interpolation method, polynomial fitting method and multivariate nonlinear regression analysis. In the case of steady state motion, the two methods are compared and compared with the hydrodynamic simulation results. Finally, a more suitable method is selected as the basis of cable location inversion and applied to deep-sea towing operations.展开更多
With the continuous improvement of the social and economic level, the number of vehicles has exploded in the city, and traditional manual identification license plates have been unable to meet the demand. In this pape...With the continuous improvement of the social and economic level, the number of vehicles has exploded in the city, and traditional manual identification license plates have been unable to meet the demand. In this paper, a Convolutional neural network (CNN)-based license plate recognition system is designed. The recognition module uses the CNN+LSTM+CTC model to simplify the convolutional layer structure to adapt to the lightweight training mode. The two-way LSTM structure is used to learn from both sides of the license plate to enhance the end-to-end recognition effect. Compared with the traditional scheme, the CTC loss calculation method eliminates the need for character alignment, streamlines the steps, and improves the recognition accuracy. The experiment shows that the license plate recognition software system designed in this paper has a high recognition accuracy rate of 98.59%.展开更多
C-Myc and signal transducer and activator of transcription(STAT) family proteins have been proposed to be important downstream genes of BCR-ABL, which characterizes most cases of chronic myeloid leukemia(CML). Here, w...C-Myc and signal transducer and activator of transcription(STAT) family proteins have been proposed to be important downstream genes of BCR-ABL, which characterizes most cases of chronic myeloid leukemia(CML). Here, we report a c-Myc pathway-targeted screening of seven natural anticancer compounds, in which we identified cryptotanshinone as a highly promising agent for CML therapy. Cryptotanshinone depletes c-Myc in CML by repressing the phosphorylation of STAT5.Decreased viability of K562 cells correlated with p-STAT5 suppression. Unexpectedly, imatinib activates rather than inhibits the phosphorylation of STAT3 in K562 cells. We demonstrated that cryptotanshinone, as a dual inhibitor of p-STAT5 and p-STAT3,can effectively block IL-6-mediated STAT3 activation and reverse BCR-ABL kinase-independent drug resistance. Moreover, we showed that the epigenetic rebalance between decreased BCR-ABL/STAT5/c-Myc and enhanced STAT3/multi-drug resistance(MDR) pathways is characteristic of the cancer stem cell-like property of K562/ADR. Simultaneously suppressing these two pathways using cryptotanshinone proves to be critical for the malignant network redress and MDR reversal of K562/ADR. These studies reveal the dual functions of cryptotanshinone that suppress key oncogenic proliferation and drug-resistant pathways in CML cells by targeting p-STAT5 and p-STAT3, providing a new strategy for CML therapy that takes advantage of natural products.展开更多
For the first time in 2009,the inorganic-organic hybrid perovskite materials were applied in liquid dye-sensitized solar cells.In 2013,the power conversion efficiency successfully reached 15%,followed by great amount ...For the first time in 2009,the inorganic-organic hybrid perovskite materials were applied in liquid dye-sensitized solar cells.In 2013,the power conversion efficiency successfully reached 15%,followed by great amount of research papers bursting out.Till August 2014,the highest efficiency is certified to 17.9%,and the reported efficiency is even up to 19.3%.They quickly go beyond dye-sensitized solar cells and organic solar cells.It is expected the perovskite has its efficiency same to the single-crystal silicon cells.The“game changer”of solar cells is coming.The perovskite solar cells are cheap and easily to be made,which will benefit both science and industry.This review summarized recent development of both perovskite materials and solar cell devices,not only including new material developments of perovskite compositions,structures,and fabrication methods,but also focusing on device structures,charge transfer mechanism and stability properties of perovskite solar cells.Their perspective is also estimated.展开更多
Carbon-based materials with tunable properties have emerged as promising candidates to replace Pt-based catalysts for accelerating oxygen reduction reaction(ORR)in fuel cells or metal-air batteries.In this work,we con...Carbon-based materials with tunable properties have emerged as promising candidates to replace Pt-based catalysts for accelerating oxygen reduction reaction(ORR)in fuel cells or metal-air batteries.In this work,we constructed a carbon hybrid which consists of one-dimensional(1D)carbon nanotubes and flake-like carbons by pyrolysis of leaf-like metal-organic frameworks.The optimal hybrid electrocatalyst of Fe_(7%)-L-CNT-900 possesses the desired features for ORR,including active Fe species,high degree of graphitization,large specific surface area,and hierarchical porous structures.Consequently,Fe_(7%)-L-CNT900 performs a high electrocatalytic activity for ORR with a half-wave potential of 0.88 V,which is comparable to that of Pt/C(20 wt.%).This strategy provides an insight into the investigation of highly efficient and low-cost composite electrocatalyst for oxygen reduction reaction.展开更多
Skeletal muscle differentiation is a highly coordinated process that involves many cellular signaling pathways and microRNAs(miRNAs).A group of muscle-specific miRNAs has been reported to promote myogenesis by suppres...Skeletal muscle differentiation is a highly coordinated process that involves many cellular signaling pathways and microRNAs(miRNAs).A group of muscle-specific miRNAs has been reported to promote myogenesis by suppressing key signaling pathways for cell growth.However,the functional role and regulatory mechanism of most non-muscle-specific miRNAs with stage-specific changes during differentiation are largely unclear.Here,we describe the functional characterization of miR-101a/b,a pair of non-muscle-specific miRNAs that show the largest change among a group of transiently upregulated miRNAs during myogenesis in C2C12 cells.The overexpression of miR-101a/b inhibits myoblast differentiation by suppressing the p38/MAPK,Interferon Gamma,and Wnt pathways and enhancing the C/EBP pathway.Mef2a,a key protein in the p38/MAPK pathway,was identified as a direct target of miR-101a/b.Interestingly,we found that the long non-coding RNA(lncRNA)Malat1,which promotes muscle differentiation,interacts with miR-101a/b,and this interaction competes with Mef2a mRNA to relieve the inhibition of the p38/MAPK pathway during myogenesis.These results uncovered a“braking”role in differentiation of transiently upregulated miRNAs and provided new insights into the competing endogenous RNA(ceRNA)regulatory mechanism in myoblast differentiation and myogenesis.展开更多
近年来,有机太阳能电池(organic solar cells,OSCs)因其轻质、柔性、颜色可变、带隙可调,以及适用于低成本卷对卷制造工艺等优势而备受关注.在OSCs的应用中,ZnO具有高载流子迁移率、与活性层能级匹配、易于制备等优点,是最关键的电子传...近年来,有机太阳能电池(organic solar cells,OSCs)因其轻质、柔性、颜色可变、带隙可调,以及适用于低成本卷对卷制造工艺等优势而备受关注.在OSCs的应用中,ZnO具有高载流子迁移率、与活性层能级匹配、易于制备等优点,是最关键的电子传输界面材料之一.但是,ZnO纳米颗粒(nanoparticles,NPs)构成的电子传输层(electron transport layer,ETL)容易存在大量缺陷,其电子传输性能也有待进一步提升.因此,本文合成了传输性能优异的ZnO纳米棒(nanorods,NRs),将其与ZnO NPs混合制备复合薄膜,用于OSCs中的电子传输界面.通过调节与优化二者混合比例,当ZnO NRs在复合薄膜中的质量分数为50%时,器件在一个标准太阳光下的能量转换效率达到了14.50%,明显高于仅使用ZnO NPs作为ETL的器件(13.69%).这主要归功于ZnO NRs的加入,使得活性层上的电子传输界面具有更优异的电荷传输与收集性能.同时,传输层界面粗糙度的适当增加还提升了器件的光捕获能力.该研究为ZnO在高性能OSCs中的应用提供了新的思路和依据.展开更多
基金supported by the National Natural Science Foundation of China(Grant No.62271265)。
文摘In the field of quantum error mitigation,most current research separately addresses quantum gate noise mitigation and measurement noise mitigation.However,due to the typically high complexity of measurement noise mitigation methods,such as those based on estimating response matrices,the overall complexity of noise mitigation schemes increases when combining measurement noise mitigation with other quantum gate noise mitigation approaches.This paper proposes a low-complexity quantum error mitigation scheme that jointly mitigates quantum gate and measurement noise,specifically when measurement noise manifests as an amplitude damping channel.The proposed scheme requires estimating only three parameters to jointly mitigate both types of noise,whereas the zero-noise extrapolation method enhanced by response matrix estimation requires estimating at least six parameters under the same conditions.
基金Chinese Academy of Sciences Projects,KSCX2-EW-Z-3 and CZBZX-1
文摘Dear Editor,In this study,we re-identified the hosts of cyanophage PP.Twenty-three candidate algal strains were tested,and the results indicated that seven strains belonging to Plectonema and Phormidium are the hosts of cyanophage PP,including two previously reported filamentous cyanobacteria,Plectonema boryanum and Phormidium
基金supported by the National Basic Research Program of China (No.2008CB418006)the Major Science and Technology Program for Water Pollution Control and Treatment (No.2013ZX07102-005)+1 种基金the Natural Science Foundation of China--Yunnan Project (No.U0833604)the National Science Foundation of China (No.31123001)
文摘The increasing occurrence of Microcystis blooms is of great concern to public health and ecosystem due to the potential hepatotoxic microcystins （MCs） produced by these colonial cyanobacteria. In order to interpret the relationships between variations of Microcyst/s morphospedes and extracellular MC concentrations, the seasonal dynamics of phytoplankton community composition, MC concentrations, and environmental parameters were monitored monthly from August, 2009 to July, 2010. The results indicated that Microcystis dominated total phytoplankton abundance from May to December （96%--99% of total biovolume）, with toxic Microcystis viridis and non-toxic Microcystis wesenbergii dominating after July （constituting 65%- 95% of the Microcystis population）, followed by M. viridis as the sole dominant species from November to January （49%--93%）. Correlation analysis revealed that water temperature and nutrient were the most important variables accounting for the occurrence ofM. wesenbergii, while the dominance ofM. viridis was related with nitrite and nitrate. The relatively low content of MCs was explained by the association with a large proportion of M. viriclis and M. wesenbergii, small colony size of Microcystis populations, and low water temperature, pH and dissolved oxygen. The extracellular MC （mean of 0.5 ± 0.2 μg/L） of water samples analyzed by enzyme-linked immunosorbent assay （ELISA） demonstrated the low concentrations of MC in Dianchi Lake which implied the low potential risk for human health in the basin. The survey provides the first whole lake study of the occurrence and seasonal variability of Microcyst/s population and
基金the National Natural Science Foundation of China(Nos.51868050,51938007,51878325,51868052,52100186,52170082,and 52063024)the Natural Science Foundation of Jiangxi Province(Nos.20202BAB213011 and 20181BBG78034)the Scientific Research Foundation of Nanchang Hangkong University(No.EA201902377)。
文摘Owing to the exorbitant overpotential and serious carrier recombination of graphitic carbon nitride(gC_(3)N_(4)),noble metal(NM)is usually served as the H_(2)evolution co-catalyst.Although the NM(such as Pt)nanoparticles can reduce the H_(2)evolution overpotential,the weak van der Waals interaction between Pt and g-C_(3)N_(4)makes against the charge transfer.Herein,the solvothermal method is developed to achieve semi-chemical interaction between Pt and g-C_(3)N_(4)nanotube(Pt-CNNT)for fast charge transfer.Moreover,the generated in-plane homojunction of CNNT can accelerate charge separation and restrain recombination.Meanwhile,the metallic Pt is an excellent H_(2)evolution co-catalyst.Photo/electrochemical tests verify that the semi-chemical interaction can improve photogenerated charge separation and transferability of CNNT.As a result,the photocatalytic H_(2)evolution turnover frequency(TOF)of Pt-CNNT under visible light irradiation reaches up to 918 h^(-1),which is one of the highest in the g-C_(3)N_(4)-based photocatalysts.This work provides a new idea to improve the charge transfer for efficient photocatalytic H_(2)evolution.
基金supported by the National Major Science and Technology Program for Water Pollution Control and Treatment(No.2009ZX07101-013)the National High Technology Research and Development Program(863)of China(No.2009AA063005)
文摘To learn the relationship between sunlight intensity and cyanobacterial proliferations for the further control of the heavy blooms, enclosure experiment were conducted in Meiliang Bay, Lake Taihu by regulating the natural light intensities with different shading ratio （0% （full sunlight）, 10%, 25%, 50% and 75% of original natural sunlight intensities） from September to November in 2010. The results indicated that phytoplankton biomass （mean） decreased significantly when the shading ratios reached 50% or more. Higher shading ratios （e.g. 75%） were very efficient in controlling the average and total cyanobacterialbloom biomass, while 50% shading ratio was proven very effective either in controlling the peak value of phytoplankton biomass or postponing the occurrence of cyanobacterial blooms in Lake Talhu. In addition, phytoplankton composition and photosynthesis efficiency were also affected by altering the shading ratios, and in turn, they might also act on phytoplankton growth. Based on the results from the present study, intermediate shading strategies such as regulation of water level or turbidity through the hydrology regulations would probably be an effective and efficient method in controlling cyanobacterial blooms in large and shallow lakes.
基金Guangxi Natural Science Foundation(GKZ 0832273)Laboratory for Comprehensive Prevention and Control of Rocky Desertification in Karst Areas in Northwest Guangxi(XZF[2016]91)Hechi University Master s Professional Degree Construction Fund(2016HJA007).
文摘[Objectives]This study was conducted to investigate the effects of different heavy metal stresses on seed germination,in order to provide a theoretical basis for phytoremediation of soil heavy metal pollution.[Methods]With the seeds of A.julibrissin as an experimental material,the germination test of A.julibrissin seeds under different concentrations of Cu^(2+),Zn^(2+) and Pb^(2+) was carried out.The germination potential,germination rate,germination index,radicle length,embryo length and other indexes were measured.[Results]①Different heavy metals had different effects on the germination of A.julibrissin seeds.Low concentrations of Cu^(2+),Zn^(2+) and Pb^(2+) stresses had certain promotion effects on the germination of A.julibrissin seeds,but high concentrations of Cu^(2+),Zn^(2+),Pb^(2+) stresses had obvious inhibitory effects on the germination of A.julibrissin seeds.②There were obvious differences in the tolerance of A.julibrissin seeds to different metal ion stresses.According to the comparison of the average values of membership functions,the order of their tolerance to different heavy metal ions was:Zn^(2+)>Cu^(2+)>Pb^(2+).[Conclusions]In the case of light pollution,the germination of A.julibrissin seeds was not inhibited,and the use of this plant for the remediation of lightly contaminated soil with heavy metals can also be considered.
文摘In this paper, a method for predicting the position of towline is presented. The location of the finite node is determined by installing fixed spaced attitude sensors in towline arrays, then the appropriate objective functions are selected for water depth profile and course profile respectively, and the interpolation fitting method is combined with the determined predicted positions. Through the hydrodynamic analysis of the existing towing cable’s underwater motion, the position of the towing cable under the steady state motion is obtained as the reference basis, and two methods are put forward, which are improved spline interpolation method, polynomial fitting method and multivariate nonlinear regression analysis. In the case of steady state motion, the two methods are compared and compared with the hydrodynamic simulation results. Finally, a more suitable method is selected as the basis of cable location inversion and applied to deep-sea towing operations.
文摘With the continuous improvement of the social and economic level, the number of vehicles has exploded in the city, and traditional manual identification license plates have been unable to meet the demand. In this paper, a Convolutional neural network (CNN)-based license plate recognition system is designed. The recognition module uses the CNN+LSTM+CTC model to simplify the convolutional layer structure to adapt to the lightweight training mode. The two-way LSTM structure is used to learn from both sides of the license plate to enhance the end-to-end recognition effect. Compared with the traditional scheme, the CTC loss calculation method eliminates the need for character alignment, streamlines the steps, and improves the recognition accuracy. The experiment shows that the license plate recognition software system designed in this paper has a high recognition accuracy rate of 98.59%.
基金supported by the National Natural Science Foundation of China (31471223, 31230042, 31771459, 31770879)the Project of Science and Technology of Guangzhou (201504010022)the National Key R&D Program of China (2017YFA0504400) from the Ministry of Science and Technology of China
文摘C-Myc and signal transducer and activator of transcription(STAT) family proteins have been proposed to be important downstream genes of BCR-ABL, which characterizes most cases of chronic myeloid leukemia(CML). Here, we report a c-Myc pathway-targeted screening of seven natural anticancer compounds, in which we identified cryptotanshinone as a highly promising agent for CML therapy. Cryptotanshinone depletes c-Myc in CML by repressing the phosphorylation of STAT5.Decreased viability of K562 cells correlated with p-STAT5 suppression. Unexpectedly, imatinib activates rather than inhibits the phosphorylation of STAT3 in K562 cells. We demonstrated that cryptotanshinone, as a dual inhibitor of p-STAT5 and p-STAT3,can effectively block IL-6-mediated STAT3 activation and reverse BCR-ABL kinase-independent drug resistance. Moreover, we showed that the epigenetic rebalance between decreased BCR-ABL/STAT5/c-Myc and enhanced STAT3/multi-drug resistance(MDR) pathways is characteristic of the cancer stem cell-like property of K562/ADR. Simultaneously suppressing these two pathways using cryptotanshinone proves to be critical for the malignant network redress and MDR reversal of K562/ADR. These studies reveal the dual functions of cryptotanshinone that suppress key oncogenic proliferation and drug-resistant pathways in CML cells by targeting p-STAT5 and p-STAT3, providing a new strategy for CML therapy that takes advantage of natural products.
基金the National Natural Science Foundation of China(Nos.61177020,11121091)the National Basic Research Program of China(No.2013CB921904).
文摘For the first time in 2009,the inorganic-organic hybrid perovskite materials were applied in liquid dye-sensitized solar cells.In 2013,the power conversion efficiency successfully reached 15%,followed by great amount of research papers bursting out.Till August 2014,the highest efficiency is certified to 17.9%,and the reported efficiency is even up to 19.3%.They quickly go beyond dye-sensitized solar cells and organic solar cells.It is expected the perovskite has its efficiency same to the single-crystal silicon cells.The“game changer”of solar cells is coming.The perovskite solar cells are cheap and easily to be made,which will benefit both science and industry.This review summarized recent development of both perovskite materials and solar cell devices,not only including new material developments of perovskite compositions,structures,and fabrication methods,but also focusing on device structures,charge transfer mechanism and stability properties of perovskite solar cells.Their perspective is also estimated.
基金The authors acknowledge the financial support from the National Natural Science Foundation of China(No.22005099)sponsored by Shanghai Pujiang Program(No.19PJ1402500)and Fundamental Research Funds for the Central Universities.
文摘Carbon-based materials with tunable properties have emerged as promising candidates to replace Pt-based catalysts for accelerating oxygen reduction reaction(ORR)in fuel cells or metal-air batteries.In this work,we constructed a carbon hybrid which consists of one-dimensional(1D)carbon nanotubes and flake-like carbons by pyrolysis of leaf-like metal-organic frameworks.The optimal hybrid electrocatalyst of Fe_(7%)-L-CNT-900 possesses the desired features for ORR,including active Fe species,high degree of graphitization,large specific surface area,and hierarchical porous structures.Consequently,Fe_(7%)-L-CNT900 performs a high electrocatalytic activity for ORR with a half-wave potential of 0.88 V,which is comparable to that of Pt/C(20 wt.%).This strategy provides an insight into the investigation of highly efficient and low-cost composite electrocatalyst for oxygen reduction reaction.
基金supported by the National Natural Science Foundation of China(31970604,31701116,31770879,31771459,31900903,81870449,81974436)the Major Research Plan of the National Natural Science Foundation of China(91940000)+1 种基金the Fundamental Research Funds for the Central Universities(20lgpy112)Science and Technology New Star in ZhuJiang Guangzhou City(201806010151).
文摘Skeletal muscle differentiation is a highly coordinated process that involves many cellular signaling pathways and microRNAs(miRNAs).A group of muscle-specific miRNAs has been reported to promote myogenesis by suppressing key signaling pathways for cell growth.However,the functional role and regulatory mechanism of most non-muscle-specific miRNAs with stage-specific changes during differentiation are largely unclear.Here,we describe the functional characterization of miR-101a/b,a pair of non-muscle-specific miRNAs that show the largest change among a group of transiently upregulated miRNAs during myogenesis in C2C12 cells.The overexpression of miR-101a/b inhibits myoblast differentiation by suppressing the p38/MAPK,Interferon Gamma,and Wnt pathways and enhancing the C/EBP pathway.Mef2a,a key protein in the p38/MAPK pathway,was identified as a direct target of miR-101a/b.Interestingly,we found that the long non-coding RNA(lncRNA)Malat1,which promotes muscle differentiation,interacts with miR-101a/b,and this interaction competes with Mef2a mRNA to relieve the inhibition of the p38/MAPK pathway during myogenesis.These results uncovered a“braking”role in differentiation of transiently upregulated miRNAs and provided new insights into the competing endogenous RNA(ceRNA)regulatory mechanism in myoblast differentiation and myogenesis.
文摘近年来,有机太阳能电池(organic solar cells,OSCs)因其轻质、柔性、颜色可变、带隙可调,以及适用于低成本卷对卷制造工艺等优势而备受关注.在OSCs的应用中,ZnO具有高载流子迁移率、与活性层能级匹配、易于制备等优点,是最关键的电子传输界面材料之一.但是,ZnO纳米颗粒(nanoparticles,NPs)构成的电子传输层(electron transport layer,ETL)容易存在大量缺陷,其电子传输性能也有待进一步提升.因此,本文合成了传输性能优异的ZnO纳米棒(nanorods,NRs),将其与ZnO NPs混合制备复合薄膜,用于OSCs中的电子传输界面.通过调节与优化二者混合比例,当ZnO NRs在复合薄膜中的质量分数为50%时,器件在一个标准太阳光下的能量转换效率达到了14.50%,明显高于仅使用ZnO NPs作为ETL的器件(13.69%).这主要归功于ZnO NRs的加入,使得活性层上的电子传输界面具有更优异的电荷传输与收集性能.同时,传输层界面粗糙度的适当增加还提升了器件的光捕获能力.该研究为ZnO在高性能OSCs中的应用提供了新的思路和依据.
