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[IEEE IGARSS 2018 - 2018 IEEE International Geoscience and Remote Sensing Symposium - Valencia, Spain (2018.7.22-2018.7.27)] IGARSS 2018 - 2018 IEEE International Geoscience and Remote Sensing Symposium - Operational Derivation of Water Quality, Water Depth and Sea Bottom Type from Remote Sensing Satellite Data
摘要： An automated procedure to operationally derive water parameters from high spatial resolution coastal images is presented. The choice of imagery is Planet’s 3 m resolution images with a potential daily revisit time. A semi-analytical model is adopted and modified using a 2-step process to retrieve the water parameters from Planet’s 4-band images. Initial validation between the retrieved water depth and nautical chart depths show good results with on-going field measurements for validation of the retrieved water optical properties.
关键词： Optical,water retrieval,PlanetLabs,operational
更新于2025-09-23 15:21:21
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[IEEE IGARSS 2018 - 2018 IEEE International Geoscience and Remote Sensing Symposium - Valencia, Spain (2018.7.22-2018.7.27)] IGARSS 2018 - 2018 IEEE International Geoscience and Remote Sensing Symposium - Estimating Gravimetric Moisture of Vegetation Using an Attenuation-Based Multi-Sensor Approach
摘要： Estimating parameters for global climate models via combined active and passive microwave remote sensing data has been a subject of intensive research in recent years. A variety of retrieval algorithms has been proposed for the estimation of soil moisture, vegetation optical depth and other parameters. A novel attenuation-based retrieval approach is proposed here to globally estimate the gravimetric moisture of vegetation (????) and retrieve information about the amount of water [kg] per amount of wet vegetation [kg]. The parameter ???? is particularly interesting for agro-ecosystems, to assess the status of growing vegetation. The key feature of the proposed approach is that it relies on multi-sensor data from three sensor types (microwave radar, microwave radiometer, and lidar) to solve the physics equations and obtain ????-estimates. The comparability of these estimates to literature values as well as to results of a globally applied, retrieval approach of Grant [4], reveal the potential of the developed method.
关键词： lidar,radiometer,Multi-sensor,SMAP,vegetation water content,vegetation optical depth,radar
更新于2025-09-23 15:21:21
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[IEEE IGARSS 2018 - 2018 IEEE International Geoscience and Remote Sensing Symposium - Valencia, Spain (2018.7.22-2018.7.27)] IGARSS 2018 - 2018 IEEE International Geoscience and Remote Sensing Symposium - A Integrated Inversion Method for Estimating Global Leaf Area Index from Chinese FY-3A Mersi Data
摘要： Global leaf area index (LAI) generally produced based on the satellite sensors with 1 km spatial resolution, such as the advanced very high resolution radiometer (AVHRR), moderate resolution imaging spectroradiometer (MODIS) and VEGETATION. At present, there isn’t a LAI product estimated from the Chinese Feng Yun No. 3 (FY-3) images. This study aims to generate a 10-day composite LAI product from FY-3A with a medium resolution spectral imaging (MERSI) at global scale in 2011. Making use of the land cover type as priori knowledge, the LAI for pure vegetation types was inversed from a lookup-table (LUT) based on an stochastic three-dimensional radiative transfer model (3D RTM). For the mixed water and vegetation types, LAI was inversed based on an improved linear decomposition method. The accuracy of LAI inversion from FY-3A MERSI was assessed by LAI field measurements from the Chinese ecosystem research network (CERN) in 2011.
关键词： FY-3A MERSI,LUT,LAI,mixed water and vegetation type,stochastic 3D RTM
更新于2025-09-23 15:21:21
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Pseudomorphic Transformation of Interpenetrated Prussian Blue Analogs into Defective Nickel Iron Selenides for Enhanced Electrochemical and Photo-Electrochemical Water Splitting
摘要： A significant methodology gap remains in the construction of advanced electrocatalysts, which has collaborative defective functionalities and structural coherence that maximizes electrochemical redox activity, electrical conductivity, and mass transport characteristics. Here, a coordinative self-templated pseudomorphic transformation of an interpenetrated metal organic compound network is conceptualized into a defect-rich porous framework that delivers highly reactive and durable photo(electro)chemical energy conversion functionalities. The coordinative-template approach enables previously inaccessible synthesis routes to rationally accomplish an interconnected porous conductive network at the microscopic level, while exposing copious unsaturated reactive sites at the atomic level without electronic or structural integrity trade-offs. Consequently, porous framework, interconnected motifs, and engineered defects endow remarkable electrocatalytic hydrogen evolution reaction and oxygen evolution reaction activity due to intrinsically improved turnover frequency, electrochemical surface area, and charge transfer. Moreover, when the hybrid is coupled with a silicon photocathode for solar-driven water splitting, it enables photon assisted redox reactions, improved charge separation, and enhanced carrier transport via the built-in heterojunction and additive co-catalyst functionality, leading to a promising photo(electro)chemical hydrogen generation performance. This work signifies a viable and generic approach to prepare other functional interconnected metal organic coordinated compounds, which can be exploited for diverse energy storage, conversion, or environmental applications.
关键词： MOF,PBA,electrochemical and PEC water splitting,metal-organic
更新于2025-09-23 15:21:21
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The design and properties study of a novel styryl-pyridinium-based water-soluble fluorescent copolymer as tracing agent
摘要： A water-soluble ?uorescent copolymer poly(acrylamide-acrylic acid-styrene pyridinium) (PAAS) for detecting polymer concentration in real time was synthesized via micellar free-radical polymerization by acrylamide, acrylic acid, and styryl-pyridinium salt derivative (SP-4). The special Donor-π-Acceptor unit and ionic structure of SP-4 endued the copolymer with excellent ?uorescent properties and remarkable water solubility. The ?uorescent copolymer was fully characterized by Fourier transform infrared, 1H nuclear magnetic resonance, thermogravimetry, Ubbelohde viscosity, ultraviolet–visible spectroscopy, and ?uorescence measurements. Furthermore, the ?uorescence intensity and the concentration of PAAS were veri?ed to have ideal linear relationship with a correlation coef?cient up to 0.9993, indicating that the copolymer’s concentration can be easily measured by detecting its ?uorescence intensity. Most importantly, the introduction of water-soluble ?uorescent monomer SP-4 endowed the PAAS with good ?uorescent stability in a wide range of temperature, pH, and brine concentrations. This study demonstrated that the ?uorescent copolymer PAAS exhibits great potential application in detecting polymer concentration in various environments.
关键词： ?uorescent polymer,water-soluble,tracing agent
更新于2025-09-23 15:21:21
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Control of Spatially Homogeneous Distribution of Heteroatoms to Produce Red TiO2 Photocatalyst for Visible-Light Photocatalytic Water Splitting
摘要： The strong band-to-band absorption of photocatalysts spanning the whole visible light region (400-700 nm) is critically important for solar-driven photocatalysis. Although it is actively and widely used as photocatalyst for various reactions in the past four decades, TiO2 has a very poor ability to capture the whole-spectrum visible light. Here, by controlling the spatially homogeneous distribution of boron and nitrogen heteroatoms in anatase TiO2 microspheres with a predominance of high-energy {001} facets, a strong visible light absorption spectrum with a sharp edge beyond 680 nm is achieved. The red TiO2 with the homogeneous doping of boron and nitrogen obtained shows no increase in defects like Ti3+ that are commonly observed in doped TiO2. More importantly, it has the ability to induce photocatalytic water oxidation to produce oxygen under the irradiation of visible light beyond 550 nm and also photocatalytic reducing water to produce hydrogen under visible light. These results demonstrate the great promise of using the red TiO2 for visible light photocatalytic water splitting and also provide an attractive strategy for realizing the wide-spectrum visible light absorption of wide-bandgap oxide photocatalysts.
关键词： Titanium Dioxide,Photocatalysis,Water Splitting,Homogeneous Doping,Visible Light
更新于2025-09-23 15:21:21
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Structural, optical and photocatlytic properties of zinc oxide nanoparticles obtained by simple plant extract mediated synthesis
摘要： We report a facile and inexpensive method to prepare zinc oxide nanoparticles with different particle size and shape using Achyranthes aspera and Couroupita guianensis leaf extracts as the reducing agent and zinc nitrate as a precursor. The prepared zinc oxide nanoparticles were analyzed by various characterization methods and obtained results evidently revealed that crystalline parameter, purity, optical absorption, band gap, particle size and shape of the ZnO nanoparticles significantly influenced by the type of leaf extract used as reducing agent. Further, photocatlytic activity study obviously demonstrates that prepared samples exhibits superior photocatlytic activity for the degradation of methylene blue dye by creating superoxide anion radicals and OH radicals under photonic irradiation. Hence, prepared zinc oxide nanoparticles by plant extract mediated synthesis can be applied as a photocatlyst for the possible waste water treatment in textile industry.
关键词： Waste water treatment,Photocatalytic activity,Plant extract mediated synthesis,Methylene blue dye,Zinc oxide nanoparticles
更新于2025-09-23 15:21:21
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CuO/ZnO Heterojunction Nanoarrays for Enhanced Photoelectrochemical Water Oxidation
摘要： Photoelectrochemical (PEC) water splitting offers a promising route for producing chemical energy from abundant solar energy, but a bottleneck remains for PEC practical applications because of the lack of efficient, stable and earth-abundant photoelectrodes. Here, we report simultaneous improvements in carrier separation and light harvesting by constructing p-n heterojunctions in CuO/ZnO nanorod arrays. The novelty of this work is developing a new strategy for preparing a CuO/ZnO p-n heterojunction photoanode for PEC water splitting, in which Cu(OH)2/ZnO is first prepared by a chemical solution strategy and then transformed into CuO/ZnO by annealing. The CuO/ZnO heterojunction photoanode exhibited a significant negative shift of 150 mV for the onset potential and an approximately 4-fold enhancement in the photocurrent at 1.23 V vs reversible hydrogen electrode (RHE) compared with those of pristine ZnO NRs. This work offers a facile strategy for preparing oxide-based p-n heterojunction photoanodes for enhanced PEC water splitting.
关键词： Water Splitting,Light Absorption,Photoelectrochemical (PEC),Heterojunction,Photoanode,P-N Junction
更新于2025-09-23 15:21:21
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Fabrication of Robust Nanostructured (Zr)BiVO4/Nickel Hexacyanoferrate Core/Shell Photoanodes for Solar Water Splitting
摘要： A highly conformal 10-15 nm layer of NiFe based Prussian blue co-catalyst is coated on BiVO4 electrodes. The coating boosted the photocurrent of BiVO4 electrodes by 10-fold to 3.23 mA/cm2. A low onset potential of 0.2 V and photo-corrosion inhibition for > 50 hours are also achieved.
关键词： Prussian blue,bismuth vanadate,solar water splitting,oxygen evolution catalyst
更新于2025-09-23 15:21:21
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Surfactant-free Exfoliation of Multilayer Molybdenum Disulfide Nanosheets in Water
摘要： In this study, we report a potentially scalable method for producing multilayer molybdenum disulfide (MoS2) nanosheets. The addition of a small amount of ammonia solution can improve the exfoliation of MoS2 nanosheets in water. The surface charge induced by spontaneous adsorption of hydroxyl ions on MoS2 surfaces favors the exfoliation process. The edge charge generated by the ionization of edge-attached groups facilities the dispersion of exfoliated nanosheets in water. It is also found that smaller MoS2 nanosheets show an improved photocatalytic performance, which stems from enhanced edge effects and a reduced flake thickness. This work opens a new vista on preparation and application of multilayer MoS2 nanosheets.
关键词： edge effects,ammonia solution,dispersion,water,multilayer MoS2 nanosheets,exfoliation
更新于2025-09-23 15:21:21