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Rapid quantification and characterization of the pyrolytic lignin fraction of bio-oils by size exclusion chromatography coupled with multi-angle laser light scattering detector (SEC-MALS)
摘要： A rapid method was developed to characterize the Pyrolytic Lignin (PL) fraction of flash pyrolysis bio-oils, based on size exclusion chromatography (SEC) coupled to differential refractive index (DRI) and multi-angle laser light scattering (MALS) detectors. Two beech wood bio-oils with different PL content were used in the study. The first was produced with a single-stage condensation system (BO), while the second was an organic fraction collected in the first stage of a two-stage condensation system (F1). PL was isolated from both the BO and F1 bio-oils by the water precipitation method. Our results suggested that quantification of the pyrolytic lignin fraction of bio-oils can be performed by the SEC-MALS-DRI method provided that the specific refractive index increment (dn/dc) is known, and the integration interval is carefully chosen. Average molar mass (Mn) values for the BO and F1 samples were 580 ± 50 Da and 890 ± 50 Da, respectively. Our results indicated that the condensation system and the water precipitation method affect the average molar mass of isolated PL oligomers.
关键词： Pyrolytic lignin,Polymer characterization,Bio-oil,Biomass,Fractional condensation,SEC-MALS,Flash pyrolysis,MALS
更新于2025-09-19 17:13:59
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[IEEE IGARSS 2019 - 2019 IEEE International Geoscience and Remote Sensing Symposium - Yokohama, Japan (2019.7.28-2019.8.2)] IGARSS 2019 - 2019 IEEE International Geoscience and Remote Sensing Symposium - Measuring Leaf Equivalent Water Thickness of Short-Rotation Coppice Willow Canopy Using Terrestrial Laser Scanning
摘要： Accurate measurements of leaf Equivalent Water Thickness (EWT) can help in early detection of vegetation stress. Terrestrial Laser Scanning (TLS) intensity data have the potential to provide 3D estimates of EWT, overcoming the limitations of the 2D estimates provided by remote sensing optical data. Such limitations include the sensors being solar illumination dependent and unable to provide information about the vertical variation in EWT. In this study, intensity data from the Leica P20 and P40 commercial TLS instruments were combined in a Normalized Difference Index (NDI). NDI was used to measure EWT in six short-rotation coppice willow (Salix spp.) plots from different varieties with an average error of 7.3% (R2 = 0.8, RMSE = 0.0011 g cm-2). The effects of wind and senescence of leaves on the accuracy of the EWT estimation were also investigated.
关键词： agricultural crops,ground LiDAR,biomass energy,water stress,Vegetation water content
更新于2025-09-19 17:13:59
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[IEEE 2019 IEEE 46th Photovoltaic Specialists Conference (PVSC) - Chicago, IL, USA (2019.6.16-2019.6.21)] 2019 IEEE 46th Photovoltaic Specialists Conference (PVSC) - Epitaxial GaP grown on Silicon by MEE and MBE Techniques as a Pathway for Dilute Nitride-Si Tandem Solar Cells
摘要： For long-wavelength space-based radars, such as the P-band radar on the recently selected European Space Agency BIOMASS mission, system distortions (crosstalk and channel imbalance), Faraday rotation, and system noise all combine to degrade the measurements. A first-order analysis of these effects on the measurements of the polarimetric scattering matrix is used to derive differentiable expressions for the errors in the polarimetric backscattering coefficients in the presence of Faraday rotation. Both the amplitudes and phases of the distortion terms are shown to be important in determining the errors and their maximum values. Exact simulations confirm the accuracy and predictions of the first-order analysis. Under an assumed power-law relation between σhv and the biomass, the system distortions and noise are converted into biomass estimation errors, and it is shown that the magnitude of the deviation of the channel imbalance from unity must be 4–5 dB less than the crosstalk, or it will dominate the error in the biomass. For uncalibrated data and midrange values of biomass, the crosstalk must be less than ?24 dB if the maximum possible error in the biomass is to be within 20% of its true value. A less stringent condition applies if the amplitudes and phases of the distortion terms are considered random since errors near the maximum possible are very unlikely. For lower values of the biomass, the noise becomes increasingly important because the σhv signal-to-noise ratio is smaller.
关键词： Biomass,Faraday rotation,polarimetric measurements,system distortion,calibration,long-wavelength radar
更新于2025-09-19 17:13:59
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ESTIMATING SINGLE TREE STEM AND BRANCH BIOMASS USING TERRESTRIAL LASER SCANNING
摘要： This paper presents a novel non-destructive approach for individual tree stem and branch biomass estimation using terrestrial laser scanning data. The study area is located at the Royal Belum Reserved Forest area, Gerik, Perak. Each forest plot was designed with a circular shape and contains several scanning locations to ensure good visibility of each tree. Unique tree signage was located on trees with diameter at breast height (DBH) of 10cm and above. Extractions of individual trees were done manually and the matching process with the field collected tree properties were relied on the tree signage and tree location as collected by total station. Individual tree stems were reconstructed based on cylinder models from which the total stem volume was calculated. Biomass of individual tree stems was calculated by multiplying stem volume with specific wood density. Biomass of individual was estimated using similar concept of tree stem with the volume estimated from alpha-hull shape. The root mean squared errors (RMSE) of estimated biomass are 50.22kg and 27.20kg for stem and branch respectively.
关键词： Terrestrial laser scanner,stem and branch biomass
更新于2025-09-19 17:13:59
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Examination of the Potential of Terrestrial Laser Scanning and Structure-from-Motion Photogrammetry for Rapid Nondestructive Field Measurement of Grass Biomass
摘要： Above ground biomass (AGB) is a parameter commonly used for assessment of grassland systems. Destructive AGB measurements, although accurate, are time consuming and are not easily undertaken on a repeat basis or over large areas. Structure-from-Motion (SfM) photogrammetry and Terrestrial Laser Scanning (TLS) are two technologies that have the potential to yield precise 3D structural measurements of vegetation quite rapidly. Recent advances have led to the successful application of TLS and SfM in woody biomass estimation, but application in natural grassland systems remains largely untested. The potential of these techniques for AGB estimation is examined considering 11 grass plots with a range of biomass in South Dakota, USA. Volume metrics extracted from the TLS and SfM 3D point clouds, and also conventional disc pasture meter settling heights, were compared to destructively harvested AGB total (grass and litter) and AGB grass plot measurements. Although the disc pasture meter was the most rapid method, it was less effective in AGB estimation (AGBgrass r2 = 0.42, AGBtotal r2 = 0.32) than the TLS (AGBgrass r2 = 0.46, AGBtotal r2 = 0.57) or SfM (AGBgrass r2 = 0.54, AGBtotal r2 = 0.72) which both demonstrated their utility for rapid AGB estimation of grass systems.
关键词： Structure-from-Motion (SfM) photogrammetry,disc pasture meter,grass,aboveground biomass (AGB),compact biomass LiDAR (CBL),terrestrial laser scanning (TLS),volume
更新于2025-09-16 10:30:52
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Nondestructive Estimation of the Above-Ground Biomass of Multiple Tree Species in Boreal Forests of China Using Terrestrial Laser Scanning
摘要： Above-ground biomass (AGB) plays a pivotal role in assessing a forest’s resource dynamics, ecological value, carbon storage, and climate change effects. The traditional methods of AGB measurement are destructive, time consuming and laborious, and an efficient, relatively accurate and non-destructive AGB measurement method will provide an effective supplement for biomass calculation. Based on the real biophysical and morphological structures of trees, this paper adopted a non-destructive method based on terrestrial laser scanning (TLS) point cloud data to estimate the AGBs of multiple common tree species in boreal forests of China, and the effects of differences in bark roughness and trunk curvature on the estimation of the diameter at breast height (DBH) from TLS data were quantitatively analyzed. We optimized the quantitative structure model (QSM) algorithm based on 100 trees of multiple tree species, and then used it to estimate the volume of trees directly from the tree model reconstructed from point cloud data, and to calculate the AGBs of trees by using specific basic wood density values. Our results showed that the total DBH and tree height from the TLS data showed a good consistency with the measured data, since the bias, root mean square error (RMSE) and determination coefficient (R2) of the total DBH were ?0.8 cm, 1.2 cm and 0.97, respectively. At the same time, the bias, RMSE and determination coefficient of the tree height were ?0.4 m, 1.3 m and 0.90, respectively. The differences of bark roughness and trunk curvature had a small effect on DBH estimation from point cloud data. The AGB estimates from the TLS data showed strong agreement with the reference values, with the RMSE, coefficient of variation of root mean square error (CV(RMSE)), and concordance correlation coefficient (CCC) values of 17.4 kg, 13.6% and 0.97, respectively, indicating that this non-destructive method can accurately estimate tree AGBs and effectively calibrate new allometric biomass models. We believe that the results of this study will benefit forest managers in formulating management measures and accurately calculating the economic and ecological benefits of forests, and should promote the use of non-destructive methods to measure AGB of trees in China.
关键词： nondestructive method,above-ground biomass,DBH,bark roughness,terrestrial laser scanning
更新于2025-09-16 10:30:52
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Integrated Bioprocess Engineering || 8. Microalgae – the solar cell factory
摘要： The dramatic increase of the world population from seven billion in 2016 to an anticipated eight billion in 2030 is a global challenge. This makes an increase of food production of 40%, energy of 50%, and raw materials of 100% urgently necessary. Economics based on fossil resources has reached its limits and even now cannot meet the demands of climate and environment protection. Global carbon dioxide emissions are stable at about 40 billion tons per year but are much too high to mitigate global warming. In the Paris climate agreement of 2015 a consensus was reached to reduce greenhouse gases and environmental destruction. But how can that be done and what is the contribution of process engineering?
关键词： photobiotechnology,sustainability,solar cell factory,biomass,microalgae
更新于2025-09-16 10:30:52
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The fabrication of a biomass carbon quantum dot-Bi <sub/>2</sub> WO <sub/>6</sub> hybrid photocatalyst with high performance for antibiotic degradation
摘要： A novel biomass carbon quantum dots@Bi2WO6 (BC-QDs@Bi2WO6) photocatalyst with uniform dispersivity was prepared via a dialysis-assisted hydrothermal process. Multiple techniques including HR-TEM, XPS, UV-Vis, PL, photocurrent analysis, and electrochemical impedance spectroscopy were employed to investigate the morphology and structures as well as the optical and electronic properties of the as-prepared samples. The photocatalytic activity of BC-QDs@Bi2WO6 was assessed by the degradation of antibiotics (tetracycline, ciprofloxacin, and gatifloxacin). The improved photocatalytic activity was attributed to the quantum effect of BC-QDs, which acted as the light harvesting center, electron reservoir, and reaction center for degrading the pollutants. Furthermore, a plausible mechanism for photocatalysis was put forward according to the ESR and quenching experiments. The present work can have significant advantages in the construction of biomass carbon-based photocatalysts in pollutant degradation and improved light utilization.
关键词： Bi2WO6,dialysis-assisted hydrothermal process,photocatalyst,biomass carbon quantum dots,antibiotic degradation
更新于2025-09-16 10:30:52
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A new ratiometric fluorescence assay based on resonance energy transfer between biomass quantum dots and organic dye for the detection of sulfur dioxide derivatives
摘要： Sulfur dioxide (SO2) is considered as the fourth gas signal molecule after nitric oxide (NO), carbon monoxide (CO) and hydrogen sulfide (H2S). It plays important roles in several physiological processes. Therefore, the design and synthesis of nanoprobes for the detection of SO2 derivatives in cells is of great significance. Herein, we report a new ratiometric fluorescence nanoprobe based on resonance energy transfer (RET) between biomass quantum dots (BQDs) and organic dye (DMI) for the detection of SO2 derivatives. The proposed ratiometric fluorescence assay allows the determination of HSO3? in the range of 1.0 to 225 μM with a detection limit of 0.5 μM. Importantly, the proposed ratiometric fluorescence nanoprobe exhibits a high photostability and good selectivity for HSO3? over other chemical species including H2S and biological mercaptans. Quantitation of HSO3? in cell lysates by using the nanoprobe is demonstrated.
关键词： ratiometric fluorescence,resonance energy transfer,organic dye,Sulfur dioxide,biomass quantum dots,nanoprobe
更新于2025-09-16 10:30:52
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Feasibility and Cost Analysis of Photovoltaic-Biomass Hybrid Energy System in Off-Grid Areas of Bangladesh
摘要： In this progressing technological advancement world, hybrid systems for power generation is one of the most promising fields for any researcher. In this context, photovoltaic-biomass hybrid systems with off-grid applications have become extremely popular with both Governments and individual users in rural areas of any part of the world. This system has gained popularity because of low cost, sustainability and very effective outcome with the use of natural resources at the rural areas. In this paper a proposed hybrid system which contains photovoltaics (PV) and biomass along with an additional storage has been considered to find the different aspects from an end user point of view. It also discusses the feasibility of the proposed model for an off-grid power system located in the remote areas of Ashuganj, Bangladesh. In order to analyse the pollutant emissions and calculate the cost parameters of the proposed system, RETScreen simulation software was deployed. This research also carries out a brief financial analysis considering the annual income of the end user and the payback periods for the installed system. It endeavours to provide complete information about different parameters which also includes the environmental impacts involved in establishing the proposed system. The conventional system in the pilot area is a kerosene-based system, hence in this research, a comparison between the proposed and the conventional system has been analysed using simulated results. The simple payback of the project was estimated to be 6.9 years and this model will be able to reduce the CO2 emissions by approximately 3.81 tonnes per year. The results have significantly supported the proposed system to be more reliable, environmentally-friendly and less costly than the conventional kerosene-based system.
关键词： feasibility analysis,cost analysis,CO2 emissions,photovoltaics (PV),battery storage,renewable energy,simple payback period,biomass,off-grid electrification
更新于2025-09-16 10:30:52