This paper proposes an innovative plan and its implement strategy of Hemu urban wetland. The plan takes into consideration its historical background and current status, its protection significance, strategies, solutio...This paper proposes an innovative plan and its implement strategy of Hemu urban wetland. The plan takes into consideration its historical background and current status, its protection significance, strategies, solutions and support conditions. It highlights the landscape characteristics of rivers and lakes, and restores its historical flood prevention functions and climate regulation for the city. Especially, this paper proposes to achieve the restoration of “Mulberry-sided Fish Pond” farming style—an important agricultural heritage created by the ancestors inside the wetland, which is a unique and creative way to use low land for ecological agriculture and cycling economy. The proposed wetland sewage treatment schemes would be of practical importance to improve and enhance the ecological environment and promote the construction of ecological civilization in the region. The “Two zones—One block and Three complexes” protection and utilization plan is reasonable and feasible. It fully presents the functions of the wetland for its production, living, life forms and ecology, and is characterized by joint protection of the wetland by original residents and social public. This will result in active, instead of passive, wetland protection, like turning a “blood transfusion protection” to “hematopoietic protection”, which reflects the sustainable development. The paper offers valuable information and strategies for planning and development of urban wetland.展开更多
Restoration of grassland such as exclusion of grazing has been considered to increase aboveground plant diversity and soil fertility. However, knowledge on the effect of long-term exclusion of grazing on soil bacteria...Restoration of grassland such as exclusion of grazing has been considered to increase aboveground plant diversity and soil fertility. However, knowledge on the effect of long-term exclusion of grazing on soil bacterial community structure and diversity is not well understood. The two sites were selected in the Inner Mongolian grassland, i.e., one fenced off since 1979 (UG79) and the other continually grazed by sheep (FG) all along. Soil microbial biomass was measured using fumigation method and bacterial community structure and diversity were assessed using methods of Denaturing Gradient Gel Electrophoresis (DGGE) and clone library. Results showed that the UG79 soil had significantly higher microbial biomass carbon and nitrogen compared with the FG soil. There was a clear separation in soil bacterial community structure, but not in bacterial diversity between the two sites. Moreover, 55 clones from the UG79 soil and 56 clones from the FG soil were selected and sequenced. Phylogenetic analysis of all clone sequences indicated that bacterial communities were dominated by the groups of Actinomycetes, Proteobacteria and Bacteroidetes, but there were no significant differences in bacterial diversity between the two sites, consistent with the results obtained from DGGE. The results highlighted that although long-term exclusion of grazing increased soil microbial biomass, but it did not harbor higher bacterial diversity compared with freely grazed site.展开更多
INTRODUCTION On 24 August 2023,the Japanese government insisted on initiating the discharge of Fukushima nuclearcontaminated water into the sea,causing widespread global concerns regarding marine biological safety,sea...INTRODUCTION On 24 August 2023,the Japanese government insisted on initiating the discharge of Fukushima nuclearcontaminated water into the sea,causing widespread global concerns regarding marine biological safety,seafood and marine resources(TEPCO 2023).Although the Japanese government has consistently emphasized that the nuclear wastewater has been treated using an Advanced Liquid Processing System(ALPS),resulting in very low concentrations of various nuclear elements,and that the International Atomic Energy Agency(IAEA)has conducted real-time monitoring of the treatment process and discharge fow(IAEA 2023),people around the world still harbor signifcant concerns.Here are a few reasons for this ongoing apprehension.展开更多
Alkanoate-coated CdSe/CdS core/shell quantum dots(QDs)with near-unity photoluminescence(PL)quantum yield and monoexponential PL decay dynamics are applied for studying quasi-stationary charge transfer from photo-excit...Alkanoate-coated CdSe/CdS core/shell quantum dots(QDs)with near-unity photoluminescence(PL)quantum yield and monoexponential PL decay dynamics are applied for studying quasi-stationary charge transfer from photo-excited QDs to quinone derivatives physically-adsorbed within the ligand monolayer of a QD.Though PL quenching efficiency due to electron transfer can be up to>80%,transient PL and transient absorption spectra reveal that the charge transfer rate ranges from single-digit nanoseconds to sub-nanoseconds,which is~3 orders of magnitude slower than that of static charge transfer and〜2 orders of magnitude faster than that of collisional charge transfer.The physically-adsorbed acceptors can slowly(500-1,000 min dependent on the size of the quinone derivatives)desorb from the ligand monolayer after removal of the free acceptors.Contrary to collisional charge transfer,the efficiency of quasi-stationary charge transfer increases as the ligand length increases by providing additional adsorption compartments in the elongated hydrocarbon chain region.Because ligand monolayer commonly exists for a typical colloidal nanocrystal,the quasi-stationary charge transfer uncovered here would likely play an important role when colloidal nanocrystals are involved in photocatalysis,photovoltaic devices,and other applications related to photo-excitation.展开更多
Quantum mechanics provides a disembodied way to transfer quantum information from one quantum object to another.In theory,this quantum information transfer can occur between quantum objects of any dimension,yet the re...Quantum mechanics provides a disembodied way to transfer quantum information from one quantum object to another.In theory,this quantum information transfer can occur between quantum objects of any dimension,yet the reported experiments of quantum information transfer to date have mainly focused on the cases where the quantum objects have the same dimension.Here,we theoretically propose and experimentally demonstrate a scheme for quantum information transfer between quantum objects of different dimensions.By using an optical qubit-ququart entangling gate,we observe the transfer of quantum information between two photons with different dimensions,including the flow of quantum information from a four-dimensional photon to a twodimensional photon and vice versa.The fidelities of the quantum information transfer range from 0.700 to 0.917,all above the classical limit of 2/3.Our work sheds light on a new direction for quantum information transfer and demonstrates our ability to implement entangling operations beyond two-level quantum systems.展开更多
With high integration density and excellent optical properties, silicon photonics is becoming a promising platform for complete integration and large-scale optical quantum information processing. Scalable quantum info...With high integration density and excellent optical properties, silicon photonics is becoming a promising platform for complete integration and large-scale optical quantum information processing. Scalable quantum information applications need photon generation and detection to be integrated on the same chip, and we have seen that various devices on the silicon photonic chip have been developed for this goal. This paper reviews the relevant research results and state-of-the-art technologies on the silicon photonic chip for scalable quantum applications. Despite the shortcomings, the properties of some components have already met the requirements for further expansion. Furthermore, we point out the challenges ahead and future research directions for on-chip scalable quantum information applications.展开更多
The Einstein–Podolsky–Rosen(EPR)paradox is one of the milestones in quantum foundations,arising from the lack of a local realistic description of quantum mechanics.The EPR paradox has stimulated an important concept...The Einstein–Podolsky–Rosen(EPR)paradox is one of the milestones in quantum foundations,arising from the lack of a local realistic description of quantum mechanics.The EPR paradox has stimulated an important concept of“quantum nonlocality,”which manifests itself in three types:quantum entanglement,quantum steering,and Bell’s nonlocality.Although Bell’s nonlocality is more often used to show“quantum nonlocality,”the original EPR paradox is essentially a steering paradox.In this work,we formulate the original EPR steering paradox into a contradiction equality,thus making it amenable to experimental verification.We perform an experimental test of the steering paradox in a two-qubit scenario.Furthermore,by starting from the steering paradox,we generate a generalized linear steering inequality and transform this inequality into a mathematically equivalent form,which is friendlier for experimental implementation,i.e.,one may measure the observables only in the x,y,or z axis of the Bloch sphere,rather than other arbitrary directions.We also perform experiments to demonstrate this scheme.Within the experimental errors,the experimental results coincide with theoretical predictions.Our results deepen the understanding of quantum foundations and provide an efficient way to detect the steerability of quantum states.展开更多
文摘This paper proposes an innovative plan and its implement strategy of Hemu urban wetland. The plan takes into consideration its historical background and current status, its protection significance, strategies, solutions and support conditions. It highlights the landscape characteristics of rivers and lakes, and restores its historical flood prevention functions and climate regulation for the city. Especially, this paper proposes to achieve the restoration of “Mulberry-sided Fish Pond” farming style—an important agricultural heritage created by the ancestors inside the wetland, which is a unique and creative way to use low land for ecological agriculture and cycling economy. The proposed wetland sewage treatment schemes would be of practical importance to improve and enhance the ecological environment and promote the construction of ecological civilization in the region. The “Two zones—One block and Three complexes” protection and utilization plan is reasonable and feasible. It fully presents the functions of the wetland for its production, living, life forms and ecology, and is characterized by joint protection of the wetland by original residents and social public. This will result in active, instead of passive, wetland protection, like turning a “blood transfusion protection” to “hematopoietic protection”, which reflects the sustainable development. The paper offers valuable information and strategies for planning and development of urban wetland.
文摘Restoration of grassland such as exclusion of grazing has been considered to increase aboveground plant diversity and soil fertility. However, knowledge on the effect of long-term exclusion of grazing on soil bacterial community structure and diversity is not well understood. The two sites were selected in the Inner Mongolian grassland, i.e., one fenced off since 1979 (UG79) and the other continually grazed by sheep (FG) all along. Soil microbial biomass was measured using fumigation method and bacterial community structure and diversity were assessed using methods of Denaturing Gradient Gel Electrophoresis (DGGE) and clone library. Results showed that the UG79 soil had significantly higher microbial biomass carbon and nitrogen compared with the FG soil. There was a clear separation in soil bacterial community structure, but not in bacterial diversity between the two sites. Moreover, 55 clones from the UG79 soil and 56 clones from the FG soil were selected and sequenced. Phylogenetic analysis of all clone sequences indicated that bacterial communities were dominated by the groups of Actinomycetes, Proteobacteria and Bacteroidetes, but there were no significant differences in bacterial diversity between the two sites, consistent with the results obtained from DGGE. The results highlighted that although long-term exclusion of grazing increased soil microbial biomass, but it did not harbor higher bacterial diversity compared with freely grazed site.
基金the National Natural Science Foundation of China(32171635).
文摘INTRODUCTION On 24 August 2023,the Japanese government insisted on initiating the discharge of Fukushima nuclearcontaminated water into the sea,causing widespread global concerns regarding marine biological safety,seafood and marine resources(TEPCO 2023).Although the Japanese government has consistently emphasized that the nuclear wastewater has been treated using an Advanced Liquid Processing System(ALPS),resulting in very low concentrations of various nuclear elements,and that the International Atomic Energy Agency(IAEA)has conducted real-time monitoring of the treatment process and discharge fow(IAEA 2023),people around the world still harbor signifcant concerns.Here are a few reasons for this ongoing apprehension.
基金supported by the National Natural Science Foundation of China(No.21902142)the Key Research and Development Program of Zhejiang Province(No.2020C01001).
文摘Alkanoate-coated CdSe/CdS core/shell quantum dots(QDs)with near-unity photoluminescence(PL)quantum yield and monoexponential PL decay dynamics are applied for studying quasi-stationary charge transfer from photo-excited QDs to quinone derivatives physically-adsorbed within the ligand monolayer of a QD.Though PL quenching efficiency due to electron transfer can be up to>80%,transient PL and transient absorption spectra reveal that the charge transfer rate ranges from single-digit nanoseconds to sub-nanoseconds,which is~3 orders of magnitude slower than that of static charge transfer and〜2 orders of magnitude faster than that of collisional charge transfer.The physically-adsorbed acceptors can slowly(500-1,000 min dependent on the size of the quinone derivatives)desorb from the ligand monolayer after removal of the free acceptors.Contrary to collisional charge transfer,the efficiency of quasi-stationary charge transfer increases as the ligand length increases by providing additional adsorption compartments in the elongated hydrocarbon chain region.Because ligand monolayer commonly exists for a typical colloidal nanocrystal,the quasi-stationary charge transfer uncovered here would likely play an important role when colloidal nanocrystals are involved in photocatalysis,photovoltaic devices,and other applications related to photo-excitation.
基金National Natural Science Foundation of China(61974168)Special Project for Research and Development in Key Areas of Guangdong Province(2018B030329001,2018B030325001)National Key Research and Development Program of China(2017YFA0305200,2016YFA0301300)。
文摘Quantum mechanics provides a disembodied way to transfer quantum information from one quantum object to another.In theory,this quantum information transfer can occur between quantum objects of any dimension,yet the reported experiments of quantum information transfer to date have mainly focused on the cases where the quantum objects have the same dimension.Here,we theoretically propose and experimentally demonstrate a scheme for quantum information transfer between quantum objects of different dimensions.By using an optical qubit-ququart entangling gate,we observe the transfer of quantum information between two photons with different dimensions,including the flow of quantum information from a four-dimensional photon to a twodimensional photon and vice versa.The fidelities of the quantum information transfer range from 0.700 to 0.917,all above the classical limit of 2/3.Our work sheds light on a new direction for quantum information transfer and demonstrates our ability to implement entangling operations beyond two-level quantum systems.
基金National Natural Science Foundation of China(12004373,61974168,62005239,62061160487,62075243)Innovation Program for Quantum Science and Technology(2021ZD0303200)+3 种基金Natural Science Foundation of Zhejiang Province(LQ21F050006)National Key Research and Development Program of China(2017YFA0305200)Key Research and Development Program of Guangdong Province of China(2018B030325001,2018B030329001)China Postdoctoral Science Foundation(2021T140647).
文摘With high integration density and excellent optical properties, silicon photonics is becoming a promising platform for complete integration and large-scale optical quantum information processing. Scalable quantum information applications need photon generation and detection to be integrated on the same chip, and we have seen that various devices on the silicon photonic chip have been developed for this goal. This paper reviews the relevant research results and state-of-the-art technologies on the silicon photonic chip for scalable quantum applications. Despite the shortcomings, the properties of some components have already met the requirements for further expansion. Furthermore, we point out the challenges ahead and future research directions for on-chip scalable quantum information applications.
基金National Key Research and Development Program of China(2017YFA0305200,2016YFA0301300)National Natural Science Foundation of China(11875167,12075001,12075245,61974168)+1 种基金Key R&D Program of Guangdong Province(2018B030325001,2018B030329001)Xiaoxiang Scholars Programme of Hunan Normal University.
文摘The Einstein–Podolsky–Rosen(EPR)paradox is one of the milestones in quantum foundations,arising from the lack of a local realistic description of quantum mechanics.The EPR paradox has stimulated an important concept of“quantum nonlocality,”which manifests itself in three types:quantum entanglement,quantum steering,and Bell’s nonlocality.Although Bell’s nonlocality is more often used to show“quantum nonlocality,”the original EPR paradox is essentially a steering paradox.In this work,we formulate the original EPR steering paradox into a contradiction equality,thus making it amenable to experimental verification.We perform an experimental test of the steering paradox in a two-qubit scenario.Furthermore,by starting from the steering paradox,we generate a generalized linear steering inequality and transform this inequality into a mathematically equivalent form,which is friendlier for experimental implementation,i.e.,one may measure the observables only in the x,y,or z axis of the Bloch sphere,rather than other arbitrary directions.We also perform experiments to demonstrate this scheme.Within the experimental errors,the experimental results coincide with theoretical predictions.Our results deepen the understanding of quantum foundations and provide an efficient way to detect the steerability of quantum states.