Understanding the topographic patterns of the seafloor is a very important part of understanding our planet.Although the science involved in bathymetric surveying has advanced much over the decades,less than 20%of the...Understanding the topographic patterns of the seafloor is a very important part of understanding our planet.Although the science involved in bathymetric surveying has advanced much over the decades,less than 20%of the seafloor has been precisely modeled to date,and there is an urgent need to improve the accuracy and reduce the uncertainty of underwater survey data.In this study,we introduce a pretrained visual geometry group network(VGGNet)method based on deep learning.To apply this method,we input gravity anomaly data derived from ship measurements and satellite altimetry into the model and correct the latter,which has a larger spatial coverage,based on the former,which is considered the true value and is more accurate.After obtaining the corrected high-precision gravity model,it is inverted to the corresponding bathymetric model by applying the gravity-depth correlation.We choose four data pairs collected from different environments,i.e.,the Southern Ocean,Pacific Ocean,Atlantic Ocean and Caribbean Sea,to evaluate the topographic correction results of the model.The experiments show that the coefficient of determination(R~2)reaches 0.834 among the results of the four experimental groups,signifying a high correlation.The standard deviation and normalized root mean square error are also evaluated,and the accuracy of their performance improved by up to 24.2%compared with similar research done in recent years.The evaluation of the R^(2) values at different water depths shows that our model can achieve performance results above 0.90 at certain water depths and can also significantly improve results from mid-water depths when compared to previous research.Finally,the bathymetry corrected by our model is able to show an accuracy improvement level of more than 21%within 1%of the total water depths,which is sufficient to prove that the VGGNet-based method has the ability to perform a gravity-bathymetry correction and achieve outstanding results.展开更多
A kind of solar thermochemical cycle based on methanothermal reduction of SnO2 is proposed for H2 and CO production. We find that the oxygen release capacity and thermodynamic driven force for methanothermal reduction...A kind of solar thermochemical cycle based on methanothermal reduction of SnO2 is proposed for H2 and CO production. We find that the oxygen release capacity and thermodynamic driven force for methanothermal reduction of SnO2 are large, and suggest CH4 :SnO2 = 2:1 as the feasible reduction condition for achieving high purities of syngas and avoiding vaporization of produced Sn. Subsequently, the amount of H2 and energetic upgrade factors under different oxidation conditions are compared, in which excess water vapor is found beneficial for hydrogen production and fuel energetic upgradation. Moreover, the effect of incom plete recovery of SnO2 on the subsequent cycle is underscored and explained. After accounting for factors such as isothermal operation and cycle stability, CH4 :SnO2 = 2:1 and H2O:Sn = 4:1 are suggested for highest solar-to-fuel efficiency of 46.1% at nonisothermal condition, where the reduction and oxidation temperature are 1400 and 600 K, respectively.展开更多
All-small-molecule organic solar cells (ASM OSCs) are promising for commercial application due to the well-defined chemical structures, convenient purifying process and low batch-to-batch variation. However, the simil...All-small-molecule organic solar cells (ASM OSCs) are promising for commercial application due to the well-defined chemical structures, convenient purifying process and low batch-to-batch variation. However, the similarity of molecule structures between small molecule donors and acceptors makes a hard regulation of their blend morphology, which will limit the efficiency.展开更多
With the tactful material design,skillful device engineering,and in-depth understanding of morphology optimization,organic solar cells (OSCs) have achieved considerable success.Therefore,OSCs have reached high power c...With the tactful material design,skillful device engineering,and in-depth understanding of morphology optimization,organic solar cells (OSCs) have achieved considerable success.Therefore,OSCs have reached high power conversion efficiencies (PCEs) exceeding 19%.Especially,continuously emerging new materials have been considered as one of the key factors to improve the PCEs of OSCs.Among molecular design strategies,side-chain engineering is an easy and commonly-used means which can optimize the solubility,alter intermolecular stacking arrangement,fine-tune the open circuit voltage (VOC),thus ultimately improve the performance.As hybrid side chains,silane and siloxane side chains have considerable effects,not only in increasing the carrier mobility and tuning the energy level,but also in affecting the crystallinity and molecular orientation.In this review,the latest developments in photovoltaic materials based on silane and siloxane side chains are presented to illustrate the structure-property relationships.The review comprehensively includes silane-side based polymer/small molecule donors;siloxane-side based polymer/small molecule donors,and polymer/small molecule acceptors.Then the similarities and differences between these two side chains are demonstrated.Finally,the possible applications and future prospects of silane and siloxane side chains are presented.展开更多
Rationally designed organic electro-optic (OEO) materials demonstrate ultra-large electro-optic (EO) activities, affording inorganic-organic hybrid photonic devices with low drive voltage, large bandwidth, low energy ...Rationally designed organic electro-optic (OEO) materials demonstrate ultra-large electro-optic (EO) activities, affording inorganic-organic hybrid photonic devices with low drive voltage, large bandwidth, low energy consumption, and small footprint. OEO materials hold the potential to achieve EO coefficients (r_(33)) over 1000 pm/V. Over the past decade, however, the best performance of OEO materials is limited to 300—600 pm·V^(−1). This is partly because of the concern of increasing dipole moment and optical loss due to the redshifted absorbance of high hyperpolarizability chromophores. Recent advance of theory-guided design enables the OEO materials to achieve greatly enhanced hyperpolarizability and EO activity with dipole moment and propagation loss within acceptable constraints. Simultaneously, progress in hybrid device designs has greatly shortened the length of modulating waveguide, which resulted in significantly reduced sensitivity to propagation loss from redshifted absorption of OEO materials. Driven by theory-guided design method, several high-performance OEO materials have been presented with greatly enhanced EO coefficients beyond 1000 pm·V^(−1). This brief review summarizes the strategies to improve the EO activity including molecular engineering and hyperpolarizability, highlights the recent great progress in design of high-performance OEO materials, and discusses the problems needed to be solved in application for current OEO materials.展开更多
Organic solar cells(OSCs)have become a major focus in the field of the third-generation renewable energy thanks to their outstanding advantages of low cost,light weight and flexibility.In recent years,efforts dedicate...Organic solar cells(OSCs)have become a major focus in the field of the third-generation renewable energy thanks to their outstanding advantages of low cost,light weight and flexibility.In recent years,efforts dedicated to OSCs via material design,morphology optimization,and mechanism analysis have made remarkable progress,with power conversion efficiency(PCE)exceeding 19%.However,compared with inorganic solar cells(e.g.,Si or perovskite),the performance of OSCs remains limited by non-ideal exciton and charge transport.展开更多
基金The National Key R&D Program of China under contract Nos 2022YFC3003800,2020YFC1521700 and 2020YFC1521705the National Natural Science Foundation of China under contract No.41830540+3 种基金the Open Fund of the East China Coastal Field Scientific Observation and Research Station of the Ministry of Natural Resources under contract No.OR-SECCZ2022104the Deep Blue Project of Shanghai Jiao Tong University under contract No.SL2020ZD204the Special Funding Project for the Basic Scientific Research Operation Expenses of the Central Government-Level Research Institutes of Public Interest of China under contract No.SZ2102the Zhejiang Provincial Project under contract No.330000210130313013006。
文摘Understanding the topographic patterns of the seafloor is a very important part of understanding our planet.Although the science involved in bathymetric surveying has advanced much over the decades,less than 20%of the seafloor has been precisely modeled to date,and there is an urgent need to improve the accuracy and reduce the uncertainty of underwater survey data.In this study,we introduce a pretrained visual geometry group network(VGGNet)method based on deep learning.To apply this method,we input gravity anomaly data derived from ship measurements and satellite altimetry into the model and correct the latter,which has a larger spatial coverage,based on the former,which is considered the true value and is more accurate.After obtaining the corrected high-precision gravity model,it is inverted to the corresponding bathymetric model by applying the gravity-depth correlation.We choose four data pairs collected from different environments,i.e.,the Southern Ocean,Pacific Ocean,Atlantic Ocean and Caribbean Sea,to evaluate the topographic correction results of the model.The experiments show that the coefficient of determination(R~2)reaches 0.834 among the results of the four experimental groups,signifying a high correlation.The standard deviation and normalized root mean square error are also evaluated,and the accuracy of their performance improved by up to 24.2%compared with similar research done in recent years.The evaluation of the R^(2) values at different water depths shows that our model can achieve performance results above 0.90 at certain water depths and can also significantly improve results from mid-water depths when compared to previous research.Finally,the bathymetry corrected by our model is able to show an accuracy improvement level of more than 21%within 1%of the total water depths,which is sufficient to prove that the VGGNet-based method has the ability to perform a gravity-bathymetry correction and achieve outstanding results.
基金supported by the National Key R&D Program of China (Grant no. 2018YFB1502005)the National Natural Science Foundation of China (Grant nos. 51476163 , 51806209 and 81801768)Institute of Electrical Engineering, Chinese Academy of Sciences (No.Y770111CSC)
文摘A kind of solar thermochemical cycle based on methanothermal reduction of SnO2 is proposed for H2 and CO production. We find that the oxygen release capacity and thermodynamic driven force for methanothermal reduction of SnO2 are large, and suggest CH4 :SnO2 = 2:1 as the feasible reduction condition for achieving high purities of syngas and avoiding vaporization of produced Sn. Subsequently, the amount of H2 and energetic upgrade factors under different oxidation conditions are compared, in which excess water vapor is found beneficial for hydrogen production and fuel energetic upgradation. Moreover, the effect of incom plete recovery of SnO2 on the subsequent cycle is underscored and explained. After accounting for factors such as isothermal operation and cycle stability, CH4 :SnO2 = 2:1 and H2O:Sn = 4:1 are suggested for highest solar-to-fuel efficiency of 46.1% at nonisothermal condition, where the reduction and oxidation temperature are 1400 and 600 K, respectively.
基金The authors thank the National Natural Science Foundation of China(52103221,52172048)the Shandong Provincial Natural Science Foundation(ZR2021QB179,ZR2021QB024,ZR2021ZD06)the Fundamental Research Funds of Shandong University.
文摘All-small-molecule organic solar cells (ASM OSCs) are promising for commercial application due to the well-defined chemical structures, convenient purifying process and low batch-to-batch variation. However, the similarity of molecule structures between small molecule donors and acceptors makes a hard regulation of their blend morphology, which will limit the efficiency.
基金National Natural Science Foundation of China(52103221,52172048,22205130)Shandong Provincial Natural Science Foundation(ZR2021QB179,ZR2021QB024,ZR2021ZD06)+1 种基金Guangdong Natural Science Foundation of China(2023A1515012323,2023A1515010943,2022A1515110643)the National Key Research and Development Program of China(2022YFB4200400)funded by MOST and the Fundamental Research Funds of Shandong University.
文摘With the tactful material design,skillful device engineering,and in-depth understanding of morphology optimization,organic solar cells (OSCs) have achieved considerable success.Therefore,OSCs have reached high power conversion efficiencies (PCEs) exceeding 19%.Especially,continuously emerging new materials have been considered as one of the key factors to improve the PCEs of OSCs.Among molecular design strategies,side-chain engineering is an easy and commonly-used means which can optimize the solubility,alter intermolecular stacking arrangement,fine-tune the open circuit voltage (VOC),thus ultimately improve the performance.As hybrid side chains,silane and siloxane side chains have considerable effects,not only in increasing the carrier mobility and tuning the energy level,but also in affecting the crystallinity and molecular orientation.In this review,the latest developments in photovoltaic materials based on silane and siloxane side chains are presented to illustrate the structure-property relationships.The review comprehensively includes silane-side based polymer/small molecule donors;siloxane-side based polymer/small molecule donors,and polymer/small molecule acceptors.Then the similarities and differences between these two side chains are demonstrated.Finally,the possible applications and future prospects of silane and siloxane side chains are presented.
基金support of the National Natural Science Foundation of China(52172048,52103221)the Shandong Provincial Natural Science Foundation(ZR2021ZD06,ZR2021QB024,ZR2021QB179)the Fundamental Research Funds of Shandong University.
文摘Rationally designed organic electro-optic (OEO) materials demonstrate ultra-large electro-optic (EO) activities, affording inorganic-organic hybrid photonic devices with low drive voltage, large bandwidth, low energy consumption, and small footprint. OEO materials hold the potential to achieve EO coefficients (r_(33)) over 1000 pm/V. Over the past decade, however, the best performance of OEO materials is limited to 300—600 pm·V^(−1). This is partly because of the concern of increasing dipole moment and optical loss due to the redshifted absorbance of high hyperpolarizability chromophores. Recent advance of theory-guided design enables the OEO materials to achieve greatly enhanced hyperpolarizability and EO activity with dipole moment and propagation loss within acceptable constraints. Simultaneously, progress in hybrid device designs has greatly shortened the length of modulating waveguide, which resulted in significantly reduced sensitivity to propagation loss from redshifted absorption of OEO materials. Driven by theory-guided design method, several high-performance OEO materials have been presented with greatly enhanced EO coefficients beyond 1000 pm·V^(−1). This brief review summarizes the strategies to improve the EO activity including molecular engineering and hyperpolarizability, highlights the recent great progress in design of high-performance OEO materials, and discusses the problems needed to be solved in application for current OEO materials.
文摘Organic solar cells(OSCs)have become a major focus in the field of the third-generation renewable energy thanks to their outstanding advantages of low cost,light weight and flexibility.In recent years,efforts dedicated to OSCs via material design,morphology optimization,and mechanism analysis have made remarkable progress,with power conversion efficiency(PCE)exceeding 19%.However,compared with inorganic solar cells(e.g.,Si or perovskite),the performance of OSCs remains limited by non-ideal exciton and charge transport.