- 标题
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- 实验方案
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Enhanced removal and detection of benzo[a]pyrene in environmental water samples using carbon dots-modified magnetic nanocomposites
摘要： Magnetic nanoparticles (MNPs) have already proven their e?cacy in the disposal of a wide array of environmental contaminants in recent years. However, the di?culties in dispersibility and agglomeration of MNPs arising from its own physical and chemical properties limit its large-scale application. Herein, we fabricated the carbon dots/fatty acid-coated MNPs (CDs/C11-Fe3O4) through a facile and simple method. To utilize the advantage of carbon dots, these limitations can be mitigated by diminishing the size of MNPs and modifying the surface of MNPs. Detailed characterization including VSM, FT-IR, XPS and TEM conformed that the higher adsorption capacity of CDs/C11-Fe3O4 is mainly attributed to low average size (< 8 nm), which is obviously lower than that of C11-Fe3O4 (about 13 nm). The CDs/C11-Fe3O4 showed higher adsorption performance than that of C11-Fe3O4 nanocomposites (76.23 ng mg?1 for CDs/C11-Fe3O4 and 59.89 ng mg?1 for C11-Fe3O4). The adsorption processes of BaP on both C11-Fe3O4 and CDs/C11-Fe3O4 nanocomposites are exothermic, and well simulated by pseudo-second-order model. Moreover, the CDs/C11-Fe3O4 were also applied for the detection of BaP in large-volume water samples, which satis?es the China environmental protection standard, are promising candidates for water remediation.
关键词： Magnetic nanocomposites,Carbon dots,Hydrophilicity,Adsorption,Benzo[a]pyrene
更新于2025-11-14 17:15:25
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Synthesis of High Performance Cyclic Olefin Polymers (COPs) with Ester Group via Ring-Opening Metathesis Polymerization
摘要： Novel ester group functionalized cyclic olefin polymers (COPs) with high glass transition temperature, high transparency, good mechanical performance and excellent film forming ability have been achieved in this work via efficient ring-opening metathesis copolymerization of exo-1,4,4a,9,9a,10-hexahydro-9,10(1′,2′)-benzeno-l,4-methanoanthracene (HBM) and comonomers (5-norbornene-2-yl methylacetate (NMA), 5-norbornene-2-yl methyl 2-ethylhexanoate (NME) or 5-norbornene-2-yl methyldodecanoate (NMD)) utilizing the Grubbs first generation catalyst, Ru(CHPh)(Cl)2(PCy3)2 (Cy = cyclohexyl, G1), followed by hydrogenation of double bonds in the main chain. The fully hydrogenated copolymers were characterized by nuclear magnetic resonance, FT-IR spectroscopy analysis, gel permeation chromatography, and thermo gravimetric analysis. Differential scanning calorimetry curves showed that the glass transition temperatures (Tg) linearly decreased with the increasing of comonomers content, which was easily controlled by changing feed ratios of HBM and comonomers. Static water contact angles tests indicate that hydrophilicity of copolymers can also be modulated by changing the comonomers incorporation. Additionally, the mechanical performances of copolymers were also investigated.
关键词： dimensional stability,optical materials,COPs (cyclic olefin polymers),ROMP (ring-opening metathesis polymerization),hydrophilicity
更新于2025-09-23 15:22:29
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Contact Angle Relaxation and Long-lasting Hydrophilicity of Sputtered Anatase TiO <sub/>2</sub> Thin Films by Novel Quantitative XPS Analysis
摘要： The contact angle relaxation of TiO2 surfaces is an important problem that must be understood, particularly for long-lasting hydrophilicity under dark conditions. The relaxation of sputtered anatase TiO2 thin films over a long time (~22 days) in an atmospheric environment was observed using quantitative XPS analysis. A new peak was identified as H2O within a donor-acceptor complex at ~2.57 eV above the lattice oxygen peak. This donor?acceptor complex turns out to be a key factor for long lasting hydrophilicity, and our model is presented. Adventitious carbon contamination was not the main cause of the contact angle relaxation. Instead, samples with lower amounts of donor?acceptor complexes (IDAC/Ibulk ≤ ~5%) underwent contact angle relaxation over time, and samples with a high density of donor?acceptor complexes (IDAC/Ibulk ≥ ~10%) showed good hydrophilicity (contact angle ≤ 20°) over 22 days. Larger amounts of basic Ti?OH relative to acidic OHbridge (ITi?OH/Ibridge ≥ 1) resulted in greater amounts of donor?acceptor complexes (IDAC/Ibulk ≥ ~10%). Thus, basic Ti?OH groups interact with H2O by forming a strong electrostatic donor?acceptor complex, leading to long-lasting hydrophilicity. Indeed, TiO2 was transformed to show long lasting hydrophilicity by high-density oxygen plasma treatment by forming sufficient Ti?OH groups and H2O molecules in the donor?acceptor complexes. Contact angle relaxation is closely related to the interactions between water molecules and the TiO2 surface in the dark. It is suggested that the relaxation depends on the number of electrostatic donor?acceptor complexes. This study provides new insight by linking theoretical studies with the experimental contact angle at the TiO2 surface in an ambient environment and is the first study that provides the presented relaxation mechanism.
关键词： Hydrophilicity,Sputtering,Plasma treatment,Contact angle relaxation,XPS analysis,Donor-acceptor complex,TiO2 thin films
更新于2025-09-23 15:22:29
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Phase-Control-Enabled Enhancement in Hydrophilicity and Mechanical Toughness in Nanocrystalline Tungsten Oxide Films for Energy-Related Applications
摘要： We report on the phase-control-enabled enhancement in the hydrophilicity and mechanical properties of nanostructured WO3 films for energy-related applications. Nanostructured WO3 films were fabricated by utilizing reactive magnetron sputter deposition onto silicon (100) substrates with varying deposition temperature (Ts = 25?500 °C) at a fixed oxygen partial pressure of ～4 mTorr. Extensive characterization performed indicates that the fundamental surface/interface structure?phase?hydrophilicity?mechanical property correlation enables tailoring nanocrystalline WO3 films to meet the requirements of various technological applications. Crystal structure, surface/interface morphology, and microstructure characterization indicate the deposition processing conditions induce phase transformations and surface/interface quality variation, which in turn controls the hydrophilicity and mechanical behavior of WO3 films. Carefully tuned processing conditions induce an amorphous to crystalline structural transformation, which progresses through amorphous to monoclinic to tetragonal phases, coupled with variation in surface roughness and crystallite size. Mechanical characterization using nanoindentation reveals that the mechanical response, in terms of hardness (H), elastic modulus (E), and scratch parameters, of WO3 films is highly sensitive to their phase and microstructure evolution. Nanostructured WO3 films crystallized in monoclinic phase exhibit superior mechanical response compared to either amorphous or tetragonal phase WO3 films. The maximum hardness (～38 GPa) and elastic modulus (～320 GPa) values were obtained for WO3 films deposited at Ts = 400 °C. The phase transformation sequence coupled with surface/interface structure affects the contact angle values significantly. The contact angle decreases significantly from 70° to nearly 5° with variation in phase, microstructure, and surface/interface quality of WO3 films. A direct structure?phase?microstructure?hydrophilicity?mechanical property relationship found suggest that tuning properties of WO3 films for photoelectrochemical, photocatalytic, and energy-related applications can be achieved by tuning the deposition conditions and controlling the phase at the nanoscale dimensions.
关键词： WO3 thin films,hydrophilicity,phase transformation,nanostructure
更新于2025-09-23 15:19:57
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[IEEE 2019 SBFoton International Optics and Photonics Conference (SBFoton IOPC) - Sao Paulo, Brazil (2019.10.7-2019.10.9)] 2019 SBFoton International Optics and Photonics Conference (SBFoton IOPC) - Femtosecond Laser Micromachining for Controlling Surface Wettability
摘要： The use of femtosecond laser to modify the surface of polymeric materials has received great attention in the last decade, due to the possibilities of tailoring the material’s properties yielding technological applications. Here, we report on the microfabrication of an azopolymer by using femtosecond laser pulses, aiming at the control of surface wettability. By properly patterning the polymeric surface structure we were able to increase the surface hydrophilicity, decreasing the water contact angle in about 20 degrees.
关键词： Laser ablation,hydrophilicity,femtosecond micromachining,azopolymer
更新于2025-09-16 10:30:52
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Nonaqueous synthesis of TiO2 nanorods using inductively coupled plasma
摘要： Titanium dioxide (TiO2) nanorods are widely used in many fields such as self-cleaning surfaces, photocatalytic lithography and pollutant control, owing to their outstanding physical, chemical and optical properties. Traditional methods for synthesizing TiO2 nanorods are mostly tedious with high cost and tremendous energy consumption. In this work, TiO2 nanorods with excellent optical, electrochemical, and hydrophilic properties were rapidly synthesized on titanium alloy (TC4) by using inductively coupled plasma (ICP) with strong chemical reactivity and high temperature characteristic. XRD patterns and SEM images confirm the conversion of TC4 into rutile TiO2 nanorods after irradiated by ICP at 800 W for only one pass, and the nanorods tend to grow longitudinally under prolonged ICP processing. Moreover, the well-developed single-crystalline feature of TiO2 nanorod is affirmed by TEM test. To reveal the growth mechanism of TiO2 nanorods, three types of substrates (polished TC4 by electrochemical polishing (ECP), polished TA2 by ECP and oxidized TC4 by anodizing) were used to grow TiO2 nanorods. However, TiO2 nanorods with good morphology were only formed on the first type of substrate due to the existence of β phase Ti, which could suppress thermal transmission between grains. In addition, the results of UV–Vis absorption spectrum, electrochemical test, and static water contact angle of the treated TC4 samples show that TiO2 nanorods synthesized by ICP possess excellent optical, electrochemical, and hydrophilic properties.
关键词： Inductively coupled plasma,Hydrophilicity,Optical property,TiO2 nanorods,Thermal oxidation
更新于2025-09-12 10:27:22
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Photo-activated implants: a triple-blinded, split-mouth, randomized controlled clinical trial on the resistance to removal torque at various healing intervals
摘要： Objectives Hydrophilic implant surfaces promote faster osseointegration of dental implants with a higher bone-implant contact (BIC) rate. Animal and in vitro studies proved that ultraviolet (UV) irradiation of titanium implants regains hydrophilicity. Clinical impact is still unclear. The objective of this RCT was to assess the removal torque (RT) required to unfix a surface-treated implant (test group) versus the original surface implant (control group) performed at various points in time. The null hypothesis stated that test and control implants will show the same deliberation force at specific time points. Material and methods One hundred eighty partially edentulous patients were randomly assigned to six groups. In single-stage surgery, each patient received one test and one control implant. In total, 180 test and 180 control implants were placed epicrestally. Test implants received a surface treatment with UV irradiation prior to insertion, in order to reduce carbon and enhance hydrophilicity and thus wettability. Maximum RT values for test and control implants were recorded with a torque measuring device at implant placement (T1), after 1 (group 1), 2 (group 2), 3 (group 3), 4 (group 4), 6 (group 5) (T2), and 8 weeks (group 6) of healing. Subsequently, implants were returned to their original position for the continuation of the healing process. Results No implant was lost. Age, gender, smoking, implant position, and bone quality could be excluded as confounding factors because of the lack of statistical significance. At T2, RT values were higher for test implants compared with those for control implants, being statistically significant in groups 2, 3, 4, and 6 (p < 0.05). Conclusions Our data support rejection of the null hypothesis. Clinical relevance Photo-activation of the surface of titanium implants leads to higher resistance to RT forces compared with that of non-treated implants, indicating improved healing and implant stability especially in the early healing phase.
关键词： Bone to implant contact rate,Photo-activated implants,Removal torque,Hydrophilicity,healing intervals
更新于2025-09-11 14:15:04
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Research on the Effects of Process Parameters on Surface Roughness in Wet-Activated Silicon Direct Bonding Base on Orthogonal Experiments
摘要： Surface roughness is a very important index in silicon direct bonding and it is affected by processing parameters in the wet-activated process. These parameters include the concentration of activation solution, holding time and treatment temperature. The effects of these parameters were investigated by means of orthogonal experiments. In order to analyze the wafer roughness more accurately, the bear ratio of the surface was used as the evaluation index. From the results of the experiments, it could be concluded that the concentration of the activation solution affected the roughness directly and the higher the concentration, the lower the roughness. Holding time did not affect the roughness as acutely as that of the concentration, but a reduced activation time decreased the roughness perceptibly. It was also discovered that the treatment temperature had a weak correlation with the surface roughness. Based on these conclusions, the parameters of concentration, temperature and holding time were optimized respectively as NH4OH:H2O2=1:1 (without water), 70 °C and 5 min. The results of bonding experiments proved the validity of the conclusions of orthogonal experiments.
关键词： wet activation,process optimization,wafer bonding,surface hydrophilicity
更新于2025-09-09 09:28:46
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Persistent hydrophilicity for Titanium oxide (TiO2) thin films by Silicon oxide (SiO2) over nanolayers
摘要： SiO2 thin layers in thicknesses (1, 5, 10, 18 nm) on TiO2 thin layer in thickness 79 nm deposited by reactive RF sputtering technique. The deposited films were heat treated at temperatures (200, 400, 500, 600°C). The surface properties of thin films by atomic force microscopy (AFM), surface chemical composition by X-ray photoelectron spectroscopy (XPS) and self-cleaning effect in bi layers, were studied. In addition, enhanced hydrophilicity property in the films under the effect of annealed temperature and persistence without UV light illumination were evaluated.
关键词： Nanolayers,X-ray photoelectron spectroscopy (XPS),hydrophilicity,annealed temperature
更新于2025-09-09 09:28:46