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Development of Raman Lidar for Remote Sensing of CO2 Leakage at an Artificial Carbon Capture and Storage Site
摘要： We developed a Raman lidar system that can remotely detect CO2 leakage and its volume mixing ratio (VMR). The system consists of a laser, a telescope, an optical receiver, and detectors. Indoor CO2 cell measurements show that the accuracy of the Raman lidar is 99.89%. Field measurements were carried out over a four-day period in November 2017 at the Eumsong Environmental Impact Evaluation Test Facility (EIT), Korea, where a CO2 leak was located 0.2 km from the Raman lidar. The results show good agreement between CO2 VMR measured by the Raman lidar system (CO2 VMRRaman LIDAR) and that measured by in situ instruments (CO2 VMRIn-situ). The correlation coefficient (R), mean absolute error (MAE), root mean square error (RMSE), and percentage difference between CO2 VMRIn-situ and CO2 VMRRaman LIDAR are 0.81, 0.27%, 0.37%, and 4.92%, respectively. The results indicate that Raman lidar is an effective tool in detecting CO2 leakage and in measuring CO2 VMR remotely.
关键词： CO2,CO2 leakage remote sensing,Carbon capture and storage,Raman lidar
更新于2025-09-23 15:22:29
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Controlling Silver Ion Release from Ag-Based Nanocoatings by Plasma Surface Engineering
摘要： Environmental surfaces have been widely recognized as an important source of hospital-associated transmissions. A number of silver-based antibacterial coatings have been reported in the literature. However, the success of any antibacterial strategy depends on the ability to control the kinetics of the silver ions released from the coating. The novel strategy proposed in this work is based on plasma surface engineering for a controlled-release of silver ions. Plasma-based nanocoatings, plasma oxidation processes and surface patterning of silver coatings were designed and optimized. Surface analyses such as XPS and AFM, as well as silver ion release over 168 h, was evaluated by MIP-AES. Results showed that surface plasma engineering successfully allow tuning the silver release and bioactivity in Ag-containing antibacterial coatings.
关键词： diamond-like carbon,plasma oxidation,silver release,antibacterial activity
更新于2025-09-23 15:22:29
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Double-layer Electromagnetic Wave Absorber Based on Carbon Nanotubes Doped with La(NO3)3 and Fe3O4 Nanoparticles
摘要： Double-layer structure absorbing materials based on the impedance matching principle and transmission line theory can effectively improve the electromagnetic wave absorbing properties. In this paper, the electromagnetic wave absorbing properties of double-layer absorbers (MWCNT)-La(NO3)3/polyvinyl chloride (PVC) and MWCNT-Fe3O4/PVC composites had been taken turns as the absorption layer and matching layer, were investigated in 2 – 18 GHz range. The absorbing properties of single- and double-layer structure and different each-layer thickness with two types of combinations were compared. The results showed that the design of double-layer structure for composites could effectively broaden the absorption frequency area, and increase the absorption intensity. When MWCNT-La(NO3)3/PVC composite were used as absorption layers with 0.6 mm thickness, the absorption bandwidth (< – 15 dB or > 97 %) of double-layer composite was the widest, reaching a maximum of about 3.36 GHz, and the absorption peak value was also the lowest about – 46.02 dB at 16.24 GHz.
关键词： La(NO3)3,multiwall carbon nanotubes,Fe3O4,electromagnetic wave absorbing properties
更新于2025-09-23 15:22:29
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Evaluation of [ <sup>11</sup> C]NMS-E973 as a PET tracer for <i>in vivo</i> visualisation of HSP90
摘要： Heat shock protein 90 is an ATP-dependent molecular chaperone important for folding, maturation and clearance of aberrantly expressed proteins and is abundantly expressed (1-2% of all proteins) in the cytosol of all normal cells. In some tumour cells, however, strong expression of HSP90 is also observed on the cell membrane and in the extracellular matrix and the affinity of tumoural HSP90 for ATP domain inhibitors was reported to increase over 100-fold compared to that of HSP90 in normal cells. Here, we explore [11C]NMS-E973 as a PET tracer for in vivo visualisation of HSP90 and as a potential tool for in vivo quantification of occupancy of HSP90 inhibitors. Methods: HSP90 expression was biochemically characterized in a panel of established cell lines including the melanoma line B16.F10. B16.F10 melanoma xenograft tumour tissue was compared to non-malignant mouse tissue. NMS-E973 was tested in vitro for HSP90 inhibitory activity in several tumour cell lines. HSP90-specific binding of [11C]NMS-E973 was evaluated in B16.F10 melanoma cells and B16.F10 melanoma, prostate cancer LNCaP and PC3, SKOV-3 xenograft tumour slices and in vivo in a B16.F10 melanoma mouse model. Results: Strong intracellular upregulation and abundant membrane localisation of HSP90 was observed in the different tumour cell lines, in the B16.F10 tumour cell line and in B16.F10 xenograft tumours compared to non-malignant tissue. NMS-E973 showed HSP90-specific inhibition and reduced proliferation of cells. [11C]NMS-E973 showed strong binding to B16.F10 melanoma cells, which was inhibited by 200 μM of PU-H71, a non-structurally related HSP90 inhibitor. HSP90-specific binding was observed by in vitro autoradiography of murine B16.F10 melanoma, LNCaP and PC3 prostate cancer and SKOV-3 ovary carcinoma tissue slices. Further, B16.F10 melanoma-inoculated mice were subjected to a μPET study, where the tracer showed fast and persistent tumour uptake. Pretreatment of B16.F10 melanoma mice with PU-H71 or Ganetespib (50 mg/kg) completely blocked tumour accumulation of [11C]NMS-E973 and confirmed in vivo HSP90 binding specificity. HSP90-specific binding of [11C]NMS-E973 was observed in blood, lungs and spleen of tumour-bearing animals but not in control animals. Conclusion: [11C]NMS-E973 is a PET tracer for in vivo visualisation of tumour HSP90 expression and can potentially be used for quantification of HSP90 occupancy. Further translational evaluation of [11C]NMS-E973 is warranted.
关键词： HSP90,melanoma,PET imaging,carbon-11,NMS-E973
更新于2025-09-23 15:22:29
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Carbon Nanomaterials for Bioimaging, Bioanalysis, and Therapy || Photoacoustic Imaging with Carbon Nanomaterials
摘要： Photoacoustic imaging is a novel, noninvasive biomedical imaging modality that has evolved considerably over the last few decades. As a label‐free imaging modality using both endogenous and exogenous contrast agent it has shown many advantages to safely and effectively differentiate diseased tissue from healthy tissues at a deeper depth. While endogenous light‐absorbing objects in living subjects such as hemoglobin, melanin, and glucose, have been useful in imaging, the use of exogenous contrast agents can improve the detection sensitivity and specific tissue‐targeting capabilities of photoacoustic imaging modality further. The carbon nanomaterial has been found to be one of the best contrast agents for photoacoustic imaging, which has strong absorption properties and great biocompatibility. This chapter covers the basic introduction of photoacoustic imaging and the application of carbon nanomaterials contrast agent such as imaging‐guided therapy and multimodal imaging in photoacoustic imaging.
关键词： photoacoustic imaging,contrast agents,photothermal therapy,photodynamic therapy,multimodal imaging,biomedical imaging,carbon nanomaterials
更新于2025-09-23 15:22:29
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Highly Stretchable Carbon Nanotube Fibers with Tunable and Stable Light Emission
摘要： Carbon nanotubes (CNTs) possess intriguing photoluminescence properties, and CNT fibers emit strong incandescent light thus act as macroscopic light sources. So far, straight-shaped CNT fibers are a focus of study and their emission properties are elucidated. Here, the authors show that helical-shaped single-walled carbon nanotube (SWNT) fibers produce uniform and stable incandescent light along the entire fiber under moderate voltages, and the emission intensity is tailored over a wide range by the applied voltage and the elongation of the fiber (up to 70% strain), and in a reversible way during mechanical deformation. Their highly stretchable SWNT fibers with tunable light emission have promising applications in emerging research areas such as wearable electronics and high-performance optoelectronic fiber systems.
关键词： single-wall carbon nanotubes,stretchable device,helical fiber,light emission
更新于2025-09-23 15:22:29
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Liquid exfoliation of g-C3N4 nanosheets to construct 2D-2D MoS2/g-C3N4 photocatalyst for enhanced photocatalytic H2 production activity
摘要： Although graphitic carbon nitride (g-C3N4) is an attractive photocatalyst for solar H2 generation, the preparation of g-C3N4 nanosheets via a “green” and simple method as well as the construction of highly-efficient g-C3N4-based photocatalysts are still challenges. In this study, g-C3N4 nanosheets prepared by a simple probe sonication assisted liquid exfoliation method were used to construct 2D-2D MoS2/g-C3N4 photocatalyst for photocatalytic H2 production. The 2D-2D MoS2/g-C3N4 photocatalyst containing 0.75% MoS2 showed the highest H2 evolution rate of 1155 μmol·h-1·g-1 with an apparent quantum yield of 6.8% at 420 nm monochromatic light, which is much higher than that of the optimized 0D-2D Pt/g-C3N4 photocatalyst. The high photocatalytic H2 production activity of 2D-2D MoS2/g-C3N4 photocatalyst can be attributed to the large surface area and the formed 2D interfaces between MoS2 and g-C3N4 nanosheets. As demonstrated by photoluminescence quenching and time-resolved fluorescence decay studies, the 2D interfaces can accelerate the photoinduced charge transfer, resulting in the high photocatalytic H2 production performance. This study provides a new strategy in developing highly-efficient g-C3N4-based photocatalysts for H2 production via using 2D nanojunction as a bridge to promote the photoinduced charge separation and transfer.
关键词： Hydrogen generation,Molybdenum disulfide,Graphitic carbon nitride,Photocatalysis,2D photocatalyst
更新于2025-09-23 15:22:29
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In situ derived Ni2P/Ni encapsulated in carbon/g-C3N4 hybrids from metal–organic frameworks/g-C3N4 for efficient photocatalytic hydrogen evolution
摘要： Tightly coupling multiple cocatalysts into semiconductors for efficient charge separation is a promising way to enhance photocatalytic H2 production. In this work, Ni2P/Ni nanoparticles (NPs) encapsulated in carbon/g-C3N4 hybrids derived from in situ pyrolysis and phosphidation of Ni-based metal-organic frameworks/g-C3N4 (Ni-MOF/g-C3N4) precursor were used as photocatalysts for H2-evolution under visible-light irradiation. The highest H2-evolution rate over optimized Ni2P/Ni@C/g-C3N4-550 was 18.04 mmol g?1 h?1 with 1.0 mmol L?1 of Eosin Y (EY)-sensitization (compared to 0.21 mmol g?1 h?1 without EY-sensitization), 13 times higher than that of pristine g-C3N4 (1.33 mmol g?1 h?1). The apparent quantum efficiency at 420 nm was 58.1%. This enhanced photocatalytic activity can be attributed to an efficient and rapid separation of the photo-generated charges from excited EY and g-C3N4 to Ni2P/Ni with carbon as an electron transport bridge, intimate contact of each components, staggered band alignment among g-C3N4, Ni and Ni2P, as well as accelerated proton reduction reaction by Ni2P/Ni NPs. This work provides new insights into the construction of MOFs-derived cocatalyst for photocatalytic H2 production.
关键词： H2 evolution,g-C3N4,Ni-MOF-derived,carbon materials,Ni2P/Ni
更新于2025-09-23 15:22:29
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Carbon Dots Dispersed on Graphene/SiO <sub/>2</sub> /Si: A Morphological Study
摘要： Low-dimensional carbon materials occupy a relevant role in the field of nanotechnology. Herein, the authors report a study conducted by atomic force microscopy and Raman spectroscopy on the deposition of carbon dots onto graphene surfaces. The study aims at understanding if and how the morphology and the microstructure of chemical vapor deposited graphene on Si/SiO2 may change due to the interaction with the carbon dots. Potential alteration in the graphene’s electrical properties might be detrimental for optoelectronic applications. The deposition of carbon dots dispersed in water and ethanol solvents are explored to investigate the effect of solvents with different fluidic properties. The obtained results indicate that the carbon dots do not alter the quality of graphene.
关键词： Raman spectroscopy,carbon dots,atomic force microscopy,chemical vapor deposited graphene
更新于2025-09-23 15:22:29
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Strengthened spatial charge separation over Z-scheme heterojunction photocatalyst for efficient photocatalytic H2 evolution
摘要： Graphitic carbon nitride (g-C3N4) is a very promising earth abundant and visible light response photocatalyst for H2 production. Fabricating novel nanostructure or combining with other semiconductors have been attempted to further enhance its activity. α-FeOOH, due to its structures greatly facilitating electrolyte transport, has been widely used as an excellent OER cocatalyst assisting the PEC water splitting process. However, to the best of our knowledge, it has not been attempted in photocatalytic H2 generation. Herein, g-C3N4 modi?ed with β-FeOOH was designed for the ?rst time for photocatalytic H2 production. It showed H2 production rate as 2.02 mmol·h?1·g?1, which was almost 6 times of pure g-C3N4. The signi?cantly promoted catalytic activity was ascribed to the greatly enhanced charge separation e?ciency by forming spatial separated reservoirs of photo activated electrons and holes in the Z-scheme heterojunction, corresponding to the conduction band of g-C3N4 and the valence band of β-FeOOH, respectively. Our work should be valuable for fabricating visible-light response heterojunction based photocatalysts with better photocatalytic performance.
关键词： Hydrogen evolution,β-FeOOH,Graphitic carbon nitride,Photocatalysis,Heterojunction
更新于2025-09-23 15:22:29