A nanodiamond with an embedded nitrogen-vacancy(NV)center is one of the experimental systems that can be coherently manipulated within current technologies.Entanglement between NV center electron spin and mechanical r...A nanodiamond with an embedded nitrogen-vacancy(NV)center is one of the experimental systems that can be coherently manipulated within current technologies.Entanglement between NV center electron spin and mechanical rotation of the nanodiamond plays a fundamental role in building a quantum network connecting these microscopic and mesoscopic degrees of motions.Here we present a protocol to asymptotically prepare a highly entangled state of the total quantum angular momentum and electron spin by adiabatically boosting the external magnetic field.展开更多
Photocatalysis is an environmentally friendly and energy-saving technology, which can effectively remove persistent dangerous pollutants in the water. Pitifully, optical absorption capacity and carrier separation have...Photocatalysis is an environmentally friendly and energy-saving technology, which can effectively remove persistent dangerous pollutants in the water. Pitifully, optical absorption capacity and carrier separation have become major bottlenecks for marvelous photocatalytic performance of photocatalysts.Herein, to address these issue, Nanodiamonds/yolk-shell ZnFe_(2)O_(4) spheres(NDs/ZFO) nanocomposites were successfully constructed via a facile two-step of solvothermal and calcination methods. The synthesized optimal NDs/ZFO-10 nanocomposite exhibits superior photocatalytic degradation activity of antibiotic under visible light, approximately 85% of the total tetracycline(TC) is degraded, and this photocatalyst shows durable cycling stability. This stems from two aspects of refinement: improvement of light absorption capacity and photo-induced charges migration and separation. In addition, the NDs/ZFO composite photocatalyst features excellent magnetic recovery capability, facilitating the recovery of photocatalyst in industry. This study opens a new chapter in the combination of NDs with magnetic materials, and deepens the understanding of the application of NDs modified composite photocatalysts.展开更多
Sol-gel coatings containing various amounts of hydroxylated nanodiamond(HND)particles were applied on the magnesium alloy for corrosion protection.The micrometric defects in the sol-gel coating completely disappeared ...Sol-gel coatings containing various amounts of hydroxylated nanodiamond(HND)particles were applied on the magnesium alloy for corrosion protection.The micrometric defects in the sol-gel coating completely disappeared after adding 0.01,0.02 and 0.05 wt.%of the HND nanoparticles.The AFM analyses showed that average roughness of the sol-gel film is about 6.7 nm which increases to 16.1 and 20.2 nm after incorporating 0.005 and 0.02 wt.%of the HNDs,respectively.The corrosion resistance of the coatings was tested in Harrison’s solution by means of EIS technique after 15,30,60 and 120 min immersion.The corrosion resistance of the sol-gel coating was remarkably enhanced by incorporating different contents of the HNDs and the best result was obtained for 0.01 wt.%.The results of the EIS experiments were confirmed by the potentiodynamic polarization tests.The corrosion resistance enhancement was attributed to the film compactness(due to the chemical interaction with the HNDs),formation of tortuous pathways for diffusion of the corrosive solution,and filling of the defects by the nanoparticles.However,the beneficial effect of the HNDs on the corrosion resistance gradually diminished as the content of nanoparticle was increased.Finally,the micromorphology of the sol-gel nanocomposites was studied after the corrosion tests.展开更多
A technology of mechanochemical treatment (MCT) is introduced to modify nanodiamond (ND) surface aiming to obtaining a stable suspension with well-dispersed ND particles in aqueous medium. ND investigated in this pape...A technology of mechanochemical treatment (MCT) is introduced to modify nanodiamond (ND) surface aiming to obtaining a stable suspension with well-dispersed ND particles in aqueous medium. ND investigated in this paper is a purified product of nanometer-sized diamond synthesized by explosive detonation. As obvious aggregation and sediment were observed when the sample was added into deionized water, it is crucial to conduct deaggregation and dispersion investigations. Amid a series of mechanical treatments, i.e. grinding, stirring, ultrasonic and classification, some reagents are introduced to modify the newly created surface during aggregates comminution. For the co-effects of mechanical forces and surfactants, the mean size of particles was reduced and a stable system containing ND with narrow size distribution was prepared. Mechanism of surface reaction and modification are discussed, while AFM, Zetasizer3000HS, XRD, XPS and FTIR are utilized for the analysis. The functional chemical structure of ND particle surface and surface electrical property changed during the modification processes, and the dispersion character and stability of suspension can consequently be improved.展开更多
Carbon materials have been playing important roles in advancing energyrelated technologies and offering great promise to addressing the rising global energy demands and environmental issues.Nanodiamonds,an exciting cl...Carbon materials have been playing important roles in advancing energyrelated technologies and offering great promise to addressing the rising global energy demands and environmental issues.Nanodiamonds,an exciting class of carbon materials,with excellent mechanical,chemical,electronic,and optical properties,have great potentials in energy-related applications.In this contribution,we summarized some of the recent progress on nanodiamonds for energy storage,conversion,and other related applications in sustainable energy research.We discussed the promising opportunities and outlooks for nanodiamonds in energy-related fields.展开更多
Annealing nanodiamonds(ND) at high temperatures up to 1700 ℃ is a common method to synthesize carbon onions. The transformation from NDs to carbon onions is particularly interesting because of carbon onions' pote...Annealing nanodiamonds(ND) at high temperatures up to 1700 ℃ is a common method to synthesize carbon onions. The transformation from NDs to carbon onions is particularly interesting because of carbon onions' potential in the field of tribology and their application in ultra-charge/discharge devices. In this paper, a novel surface-enhanced Raman scattering technique that involves coating the sample with nanoscopic gold particles is proposed to characterize the NDs after different annealing treatments. Conventional Raman and surfaceenhanced Raman spectra were obtained, and the changes of peak parameters as the function of annealing temperature were evaluated. It was found that the widths of the D and the G peaks decreased with increasing annealing temperature, reflecting an improved order in the sp^2-hybridized carbon during the transformation from NDs to carbon onions. After annealing at 1700 ℃, the sp^2?carbon was highly ordered, indicating desirable electrical conductivity and lubricity. With increasing annealing temperature, the D peak showed a blue shift of almost30 cm^(-1), while the G peak merely shifted by 5 cm^(-1). For annealing temperatures above 1100 ℃, an increase of intensity ratio ID/IGwas observed. Compared to the uncoated area, red shifts of 0.5-2 cm^(-1) and of 5-9 cm^(-1) for the G and D peaks, respectively, were detected for the gold-coated area, which was due to the coupling of the plasmons and the phonons of the samples.展开更多
In order to investigate the effect of nanodiamond (ND) on the mechanical properties of dental composite resins, bisphenol-A-glycidyl dimethacrylate ( Bis-GMA ), triethylene glycol dime- thacrylate ( TEGDMA), bar...In order to investigate the effect of nanodiamond (ND) on the mechanical properties of dental composite resins, bisphenol-A-glycidyl dimethacrylate ( Bis-GMA ), triethylene glycol dime- thacrylate ( TEGDMA), barium glass (BG) powder, DL-camphoroquinone (CQ) and dimethylamin- oethylmethacrylate (DMAEMA) were mixed as the matrix for the experiments. NDs of three diame- ters ( 100 nm, 220 nm, 500 nm) modified with 3-(trimethoxysilyl) propyl methacrylate (γ-MPS) were added to the mixture separately in 0. 2% to get test samples. The fiexural strength and elastic modulus of these samples and the mixture without ND (as the reference group, RG) were characterized with standard specification tests. Results reveal that the mechanical properties and elastic modulus of resins containing 220 nm ND ( R-220 ) and 500 nm ND ( R-500 ) were significantly different from those of RG. R-500 had the highest flexural strength and elastic modulus ( by average data), and all of its five specimens were found to have mean flexural strength values greater than the minimum value (80MPa) prescribed by ISO 4049: 2000. Different sizes of diamonds have different effects on mechanical properties of dental composite resins, and the performances of 220 nm and 500 nm diamonds are better than that of 100 nm diamond.展开更多
Nanodiamonds have outstanding mechanical properties,chemical inertness,and biocompatibility,which give them potential in various applications.Current methods for preparing nanodiamonds often lead to products with impu...Nanodiamonds have outstanding mechanical properties,chemical inertness,and biocompatibility,which give them potential in various applications.Current methods for preparing nanodiamonds often lead to products with impurities and uneven morphologies.We report a two-step high-pressure high-temperature(HPHT) method to synthesize nanodiamonds using naphthalene as the precursor without metal catalysts.The grain size of the diamonds decreases with increasing carbonization time(at constant pressure and temperature of 11.5 GPa and 700℃,respectively).This is discussed in terms of the different crystallinities of the carbon intermediates.The probability of secondary anvil cracking during the HPHT process is also reduced.These results indicate that the two-step method is efficient for synthesizing nanodiamonds,and that it is applicable to other organic precursors.展开更多
Several factors affecting the ζ-potential of nanodiamonds were studied. The Chemical Mechanical Modification (CMM) of surface, different surfactants and its dosage, and inorganic ions on the ζ-potential of nanodiamo...Several factors affecting the ζ-potential of nanodiamonds were studied. The Chemical Mechanical Modification (CMM) of surface, different surfactants and its dosage, and inorganic ions on the ζ-potential of nanodiamond sample L were studied using ZETASIZER3000HS and Nexus470. Results show that the ζ-potential changes with its parameters of detonation synthesis and purification. Results also suggest that CMM and subsequent treatments employed can alter apparently the ζ-potential and that some anionic surfactants increase the absolute value of the ζ-potential in the alkaline surrounding.展开更多
Fourier transform infrared spectroscopy (FT-IR) and ζ-potential were introduced to study the effect of different modification parameters on the surface properties of nanodiamond (ND). Results showed that under st...Fourier transform infrared spectroscopy (FT-IR) and ζ-potential were introduced to study the effect of different modification parameters on the surface properties of nanodiamond (ND). Results showed that under stirring grinding grinding conditions, ND hard aggregates were smashed and some active spots on them reacted with surfactant molecules, which led to the increase in its ζ-potential and stability. Different models of surface modification were also given in this study.展开更多
Onion-like carbon (OLC) was fabricated by annealing nanodiamond at 1000 ℃ for 2 hours in low vacuum (1 Pa). The OLC was characterized by X-ray diffraction (XRD), high resolution transmission electron microscopy...Onion-like carbon (OLC) was fabricated by annealing nanodiamond at 1000 ℃ for 2 hours in low vacuum (1 Pa). The OLC was characterized by X-ray diffraction (XRD), high resolution transmission electron microscopy (HRTEM), Fourier transform infrared spectroscopy (FTIR), Raman spectroscopy and differential scanning calorimetry (DSC). The experimental results show that the OLC exhibits similarity to the original nanodiamond particles in shape. The size of the OLC is found to be approximately 5 nm. The transformation mechanism of the OLC from nanodiamond was discussed also.展开更多
Nanodiamond is a new material which has the dual properties of diamond and nanomaterial.The dual properties have contributed to its wide applications in many industrial sectors.This paper briefly reviews the developme...Nanodiamond is a new material which has the dual properties of diamond and nanomaterial.The dual properties have contributed to its wide applications in many industrial sectors.This paper briefly reviews the development of nanodiamond,describes its synthesis technology under dynamic high-temperature and high-pressure conditions,and introduces its properties as well as applications.Predictions are made about nanodiamond’ s potentially successful applications in the future.展开更多
Nanodiamonds(NDs)have been widely explored for applications in drug delivery,optical bioimaging,sensors,quantum computing,and others.Room-temperature nanomanufacturing of NDs in open air using confined laser shock det...Nanodiamonds(NDs)have been widely explored for applications in drug delivery,optical bioimaging,sensors,quantum computing,and others.Room-temperature nanomanufacturing of NDs in open air using confined laser shock detonation(CLSD)emerges as a novel manufacturing strategy for ND fabrication.However,the fundamental process mechanism remains unclear.This work investigates the underlying mechanisms responsible for nanomanufacturing of NDs during CLSD with a focus on the laser-matter interaction,the role of the confining effect,and the graphite-to-diamond transition.Specifically,a first-principles model is integrated with a molecular dynamics simulation to describe the laser-induced thermo-hydrodynamic phenomena and the graphite-to-diamond phase transition during CLSD.The simulation results elucidate the confining effect in determining the material’s responses to laser irradiation in terms of the temporal and spatial evolutions of temperature,pressure,electron number density,and particle velocity.The integrated model demonstrates the capability of predicting the laser energy threshold for ND synthesis and the efficiency of ND nucleation under varying processing parameters.This research will provide significant insights into CLSD and advance this nanomanufacturing strategy for the fabrication of NDs and other high-temperature-high-pressure synthesized nanomaterials towards extensive applications.展开更多
Model test-systems for biochemical determination of glucose and cholesterol are designed by covalent coupling of enzymes to the surface of modified nanodiamonds (MND). In both cases after immobilization on MND the enz...Model test-systems for biochemical determination of glucose and cholesterol are designed by covalent coupling of enzymes to the surface of modified nanodiamonds (MND). In both cases after immobilization on MND the enzymes exhibit activity and catalyze the formation of a colored product in the chain of successive enzymatic reactions of oxidative azocoupling (Н2О2—4-aminoantipyrine—phenol). Produced MND-enzymes complexes: function in DI water and various buffers, over a wide range of temperature and pH, provide for the linear product yield over a broad concentration range of analyzed substances, make possible to test cholesterol and glucose in vitro many times, exhibit functional activity after long storage at + 4°C.展开更多
The work in this study is focused on investigation of composite nickel coatings. The coatings were deposited on ductile cast iron samples of different composition by electroless method EFTTOM NICKEL with addition of s...The work in this study is focused on investigation of composite nickel coatings. The coatings were deposited on ductile cast iron samples of different composition by electroless method EFTTOM NICKEL with addition of strengthening nanodiamond particles (2-4 nm), The samples were prepared by casting and austempering. The microstructure, microhardness and wear resistance of the coatings were investigated. The thickness of the coatings was also determined (8-10μm). Metallographic analyses, SEM (scanning electron microscopic) investigation, microhardness measurements by knoop method, wear resistance tests were carried out. The coatings with and without heat treatment at 290℃, 6 h were tested. Duplication of microhardness value and improvement of the coating's properties of heat treated coatings were observed.展开更多
The protective effect of modified nanodiamonds (MND) under the action of cobalt and nickel ions on the skin of Guinea pigs was shown. At the action of chromium ions on the skin of animals, the protective effect of MND...The protective effect of modified nanodiamonds (MND) under the action of cobalt and nickel ions on the skin of Guinea pigs was shown. At the action of chromium ions on the skin of animals, the protective effect of MND was not found. The differences are related to different adsorption properties of MND to the investigated colored metal ions. It is shown in vitro that MND can adsorb ions of cobalt and nickel and don’t bind ions of chromium from aqueous medium. The perspectives using of MND as a new drug for the prevention allergic dermatitis caused by action of bivalent ions of metals are discussed.展开更多
The effect of Chemical Mechanical Modification (CMM) and dispersants on the ζ potential of nanodiamond particles in aqueous system and the influence of the ultrasonic or shearing techniques on its size distribution w...The effect of Chemical Mechanical Modification (CMM) and dispersants on the ζ potential of nanodiamond particles in aqueous system and the influence of the ultrasonic or shearing techniques on its size distribution were studied CMM and the addition of dispersants AD 2 and AD 8 improve the stability of its suspension With ultrasonic time prolonged, the mean average size of nanodiamond decreases, while with the prolongation of shearing time, its mean size decreases first, then increases a little In the speed range used, the mean size decreases with the rising speed If the whole ultrasonic time kept constant, it is better to add the dispersants before展开更多
The methods of chemical-mechanical treatments (CMT) were utilized for surface modification of nanodiamond in aqueous medium, and a considerably stable suspension system was thus obtained. The size of all the particles...The methods of chemical-mechanical treatments (CMT) were utilized for surface modification of nanodiamond in aqueous medium, and a considerably stable suspension system was thus obtained. The size of all the particles in the provided system was less than 100 nm with a narrow distribution and excellent stability, and no obvious change of particle crystal structure after the treatments was observed. The mechanism of the treatments was also discussed. The results show that, because of mechanical treatment effect, addition of ionic surfactants and inorganic regulators, the ζ-potential of nanodiamond shifts upwards during the treatments, and the composition of surface functional groups changes. Carboxyl and hydroxyl groups are intensified after the surface modification, which may contribute to the improvement of dispersion and stability. Meanwhile, the addition of non-ionic polymer can also benefit the suspension stability.展开更多
Well-dispersed nanodiamond(ND) aqueous suspensions in both acidic and alkaline environments is prepared by mechanochemical treatment. All the ND particles in the suspensions are smaller than 100nm in dimension with a ...Well-dispersed nanodiamond(ND) aqueous suspensions in both acidic and alkaline environments is prepared by mechanochemical treatment. All the ND particles in the suspensions are smaller than 100nm in dimension with a narrow size distribution, and no destabilization phenomena were detected in a duration of more than one year. Stable dispersion of ND in the media may attributed to the strong electrostatic repulsion between particles because of the adsorption of dispersants, while mechanical forces may strengthen this adsorption reaction. Good adaptability and applicability of the suspensions to the change of ND concentration and surrounding temperature are observed, and improved performances of ND diamonds are obtained when used in ultrafine polishing and composite plating.展开更多
Benefiting from its surface-rich functional groups,eco-friendliness,impressive electrochemical properties,excellent light absorption,structural tunability at the atomic/morphological level,and ultra-high stability und...Benefiting from its surface-rich functional groups,eco-friendliness,impressive electrochemical properties,excellent light absorption,structural tunability at the atomic/morphological level,and ultra-high stability under harsh conditions,nanodiamond has emerged as a promising carbon-based non-metallic material in the field of energy conversion such as electrocatalysis and photocatalysis.Furthermore,nanodiamond,as a new generation of green catalysts,can overcome the poisoning of catalysts by complex pollutants in advanced oxidation processes,thus effectively removing organic matter from water,which is unparalleled in reducing the cost of water purification and avoiding secondary cross-contamination of water by traditional heavy metal-based catalysts.Here,we review the research and development of nanodiamonds as major electrocatalysts and photocatalysts for energy conversion and for air/water treatment for environmental remediation.The relevant properties,trimming strategy,mechanistic understanding,and design principles of nanodiamond as a catalyst are described,as well as the challenges and prospects of this emerging field.展开更多
基金Project supported by the National Key Research and Development Program of China(Grant Nos.2021YFA0718302 and 2021YFA1402104)the National Natural Science Foundation of China(Grant No.12075310)the Strategic Priority Research Program of Chinese Academy of Sciences(Grant No.XDB28000000).
文摘A nanodiamond with an embedded nitrogen-vacancy(NV)center is one of the experimental systems that can be coherently manipulated within current technologies.Entanglement between NV center electron spin and mechanical rotation of the nanodiamond plays a fundamental role in building a quantum network connecting these microscopic and mesoscopic degrees of motions.Here we present a protocol to asymptotically prepare a highly entangled state of the total quantum angular momentum and electron spin by adiabatically boosting the external magnetic field.
基金the founding support from the National Natural Science Foundation of China(21906072 and 22006057)the Natural Science Foundation of Jiangsu Province(BK20190982)+2 种基金Henan Postdoctoral Foundation(202003013)“Doctor of Mass entrepreneurship and innovation” Project in Jiangsu ProvinceOpen Fund for Hebei Province Key Laboratory of Sustained Utilization & Development of Water Recourse(HSZYL2021003)。
文摘Photocatalysis is an environmentally friendly and energy-saving technology, which can effectively remove persistent dangerous pollutants in the water. Pitifully, optical absorption capacity and carrier separation have become major bottlenecks for marvelous photocatalytic performance of photocatalysts.Herein, to address these issue, Nanodiamonds/yolk-shell ZnFe_(2)O_(4) spheres(NDs/ZFO) nanocomposites were successfully constructed via a facile two-step of solvothermal and calcination methods. The synthesized optimal NDs/ZFO-10 nanocomposite exhibits superior photocatalytic degradation activity of antibiotic under visible light, approximately 85% of the total tetracycline(TC) is degraded, and this photocatalyst shows durable cycling stability. This stems from two aspects of refinement: improvement of light absorption capacity and photo-induced charges migration and separation. In addition, the NDs/ZFO composite photocatalyst features excellent magnetic recovery capability, facilitating the recovery of photocatalyst in industry. This study opens a new chapter in the combination of NDs with magnetic materials, and deepens the understanding of the application of NDs modified composite photocatalysts.
文摘Sol-gel coatings containing various amounts of hydroxylated nanodiamond(HND)particles were applied on the magnesium alloy for corrosion protection.The micrometric defects in the sol-gel coating completely disappeared after adding 0.01,0.02 and 0.05 wt.%of the HND nanoparticles.The AFM analyses showed that average roughness of the sol-gel film is about 6.7 nm which increases to 16.1 and 20.2 nm after incorporating 0.005 and 0.02 wt.%of the HNDs,respectively.The corrosion resistance of the coatings was tested in Harrison’s solution by means of EIS technique after 15,30,60 and 120 min immersion.The corrosion resistance of the sol-gel coating was remarkably enhanced by incorporating different contents of the HNDs and the best result was obtained for 0.01 wt.%.The results of the EIS experiments were confirmed by the potentiodynamic polarization tests.The corrosion resistance enhancement was attributed to the film compactness(due to the chemical interaction with the HNDs),formation of tortuous pathways for diffusion of the corrosive solution,and filling of the defects by the nanoparticles.However,the beneficial effect of the HNDs on the corrosion resistance gradually diminished as the content of nanoparticle was increased.Finally,the micromorphology of the sol-gel nanocomposites was studied after the corrosion tests.
文摘A technology of mechanochemical treatment (MCT) is introduced to modify nanodiamond (ND) surface aiming to obtaining a stable suspension with well-dispersed ND particles in aqueous medium. ND investigated in this paper is a purified product of nanometer-sized diamond synthesized by explosive detonation. As obvious aggregation and sediment were observed when the sample was added into deionized water, it is crucial to conduct deaggregation and dispersion investigations. Amid a series of mechanical treatments, i.e. grinding, stirring, ultrasonic and classification, some reagents are introduced to modify the newly created surface during aggregates comminution. For the co-effects of mechanical forces and surfactants, the mean size of particles was reduced and a stable system containing ND with narrow size distribution was prepared. Mechanism of surface reaction and modification are discussed, while AFM, Zetasizer3000HS, XRD, XPS and FTIR are utilized for the analysis. The functional chemical structure of ND particle surface and surface electrical property changed during the modification processes, and the dispersion character and stability of suspension can consequently be improved.
基金We acknowledge the support from the Department of Energy,Office of Basic Energy Sciences,Division of Materials Sciences and Engineering,under contract DE‐AC02-76SF00515.
文摘Carbon materials have been playing important roles in advancing energyrelated technologies and offering great promise to addressing the rising global energy demands and environmental issues.Nanodiamonds,an exciting class of carbon materials,with excellent mechanical,chemical,electronic,and optical properties,have great potentials in energy-related applications.In this contribution,we summarized some of the recent progress on nanodiamonds for energy storage,conversion,and other related applications in sustainable energy research.We discussed the promising opportunities and outlooks for nanodiamonds in energy-related fields.
基金supported by National Natural Science Foundation of China (No. 51575389, 51761135106, 51511130074)National Key Research and Development Program of China (2016YFB1102203)State key laboratory of precision measuring technology and instruments (Pilt1705)
文摘Annealing nanodiamonds(ND) at high temperatures up to 1700 ℃ is a common method to synthesize carbon onions. The transformation from NDs to carbon onions is particularly interesting because of carbon onions' potential in the field of tribology and their application in ultra-charge/discharge devices. In this paper, a novel surface-enhanced Raman scattering technique that involves coating the sample with nanoscopic gold particles is proposed to characterize the NDs after different annealing treatments. Conventional Raman and surfaceenhanced Raman spectra were obtained, and the changes of peak parameters as the function of annealing temperature were evaluated. It was found that the widths of the D and the G peaks decreased with increasing annealing temperature, reflecting an improved order in the sp^2-hybridized carbon during the transformation from NDs to carbon onions. After annealing at 1700 ℃, the sp^2?carbon was highly ordered, indicating desirable electrical conductivity and lubricity. With increasing annealing temperature, the D peak showed a blue shift of almost30 cm^(-1), while the G peak merely shifted by 5 cm^(-1). For annealing temperatures above 1100 ℃, an increase of intensity ratio ID/IGwas observed. Compared to the uncoated area, red shifts of 0.5-2 cm^(-1) and of 5-9 cm^(-1) for the G and D peaks, respectively, were detected for the gold-coated area, which was due to the coupling of the plasmons and the phonons of the samples.
文摘In order to investigate the effect of nanodiamond (ND) on the mechanical properties of dental composite resins, bisphenol-A-glycidyl dimethacrylate ( Bis-GMA ), triethylene glycol dime- thacrylate ( TEGDMA), barium glass (BG) powder, DL-camphoroquinone (CQ) and dimethylamin- oethylmethacrylate (DMAEMA) were mixed as the matrix for the experiments. NDs of three diame- ters ( 100 nm, 220 nm, 500 nm) modified with 3-(trimethoxysilyl) propyl methacrylate (γ-MPS) were added to the mixture separately in 0. 2% to get test samples. The fiexural strength and elastic modulus of these samples and the mixture without ND (as the reference group, RG) were characterized with standard specification tests. Results reveal that the mechanical properties and elastic modulus of resins containing 220 nm ND ( R-220 ) and 500 nm ND ( R-500 ) were significantly different from those of RG. R-500 had the highest flexural strength and elastic modulus ( by average data), and all of its five specimens were found to have mean flexural strength values greater than the minimum value (80MPa) prescribed by ISO 4049: 2000. Different sizes of diamonds have different effects on mechanical properties of dental composite resins, and the performances of 220 nm and 500 nm diamonds are better than that of 100 nm diamond.
基金Project supported by the National Key R&D Program of China(Grant No.2018YFB0406500)the National Natural Science Foundation of China(Grant Nos.U1804155,U1604263,and 11804307)the China Postdoctoral Science Foundation(Grant Nos.2018M630830 and 2019T120631).
文摘Nanodiamonds have outstanding mechanical properties,chemical inertness,and biocompatibility,which give them potential in various applications.Current methods for preparing nanodiamonds often lead to products with impurities and uneven morphologies.We report a two-step high-pressure high-temperature(HPHT) method to synthesize nanodiamonds using naphthalene as the precursor without metal catalysts.The grain size of the diamonds decreases with increasing carbonization time(at constant pressure and temperature of 11.5 GPa and 700℃,respectively).This is discussed in terms of the different crystallinities of the carbon intermediates.The probability of secondary anvil cracking during the HPHT process is also reduced.These results indicate that the two-step method is efficient for synthesizing nanodiamonds,and that it is applicable to other organic precursors.
文摘Several factors affecting the ζ-potential of nanodiamonds were studied. The Chemical Mechanical Modification (CMM) of surface, different surfactants and its dosage, and inorganic ions on the ζ-potential of nanodiamond sample L were studied using ZETASIZER3000HS and Nexus470. Results show that the ζ-potential changes with its parameters of detonation synthesis and purification. Results also suggest that CMM and subsequent treatments employed can alter apparently the ζ-potential and that some anionic surfactants increase the absolute value of the ζ-potential in the alkaline surrounding.
基金the financial support of Jiangsu Provincial Natural Science Foundation of China (No. BK2006191) Jiangsu Provincial Foundation of Summit Talents in Six Trades (No. 06-D- 024).
文摘Fourier transform infrared spectroscopy (FT-IR) and ζ-potential were introduced to study the effect of different modification parameters on the surface properties of nanodiamond (ND). Results showed that under stirring grinding grinding conditions, ND hard aggregates were smashed and some active spots on them reacted with surfactant molecules, which led to the increase in its ζ-potential and stability. Different models of surface modification were also given in this study.
文摘Onion-like carbon (OLC) was fabricated by annealing nanodiamond at 1000 ℃ for 2 hours in low vacuum (1 Pa). The OLC was characterized by X-ray diffraction (XRD), high resolution transmission electron microscopy (HRTEM), Fourier transform infrared spectroscopy (FTIR), Raman spectroscopy and differential scanning calorimetry (DSC). The experimental results show that the OLC exhibits similarity to the original nanodiamond particles in shape. The size of the OLC is found to be approximately 5 nm. The transformation mechanism of the OLC from nanodiamond was discussed also.
文摘Nanodiamond is a new material which has the dual properties of diamond and nanomaterial.The dual properties have contributed to its wide applications in many industrial sectors.This paper briefly reviews the development of nanodiamond,describes its synthesis technology under dynamic high-temperature and high-pressure conditions,and introduces its properties as well as applications.Predictions are made about nanodiamond’ s potentially successful applications in the future.
基金National Science Foundation(NSF)under award numbers CMMI-1826439 and CMMI-1825739。
文摘Nanodiamonds(NDs)have been widely explored for applications in drug delivery,optical bioimaging,sensors,quantum computing,and others.Room-temperature nanomanufacturing of NDs in open air using confined laser shock detonation(CLSD)emerges as a novel manufacturing strategy for ND fabrication.However,the fundamental process mechanism remains unclear.This work investigates the underlying mechanisms responsible for nanomanufacturing of NDs during CLSD with a focus on the laser-matter interaction,the role of the confining effect,and the graphite-to-diamond transition.Specifically,a first-principles model is integrated with a molecular dynamics simulation to describe the laser-induced thermo-hydrodynamic phenomena and the graphite-to-diamond phase transition during CLSD.The simulation results elucidate the confining effect in determining the material’s responses to laser irradiation in terms of the temporal and spatial evolutions of temperature,pressure,electron number density,and particle velocity.The integrated model demonstrates the capability of predicting the laser energy threshold for ND synthesis and the efficiency of ND nucleation under varying processing parameters.This research will provide significant insights into CLSD and advance this nanomanufacturing strategy for the fabrication of NDs and other high-temperature-high-pressure synthesized nanomaterials towards extensive applications.
文摘Model test-systems for biochemical determination of glucose and cholesterol are designed by covalent coupling of enzymes to the surface of modified nanodiamonds (MND). In both cases after immobilization on MND the enzymes exhibit activity and catalyze the formation of a colored product in the chain of successive enzymatic reactions of oxidative azocoupling (Н2О2—4-aminoantipyrine—phenol). Produced MND-enzymes complexes: function in DI water and various buffers, over a wide range of temperature and pH, provide for the linear product yield over a broad concentration range of analyzed substances, make possible to test cholesterol and glucose in vitro many times, exhibit functional activity after long storage at + 4°C.
文摘The work in this study is focused on investigation of composite nickel coatings. The coatings were deposited on ductile cast iron samples of different composition by electroless method EFTTOM NICKEL with addition of strengthening nanodiamond particles (2-4 nm), The samples were prepared by casting and austempering. The microstructure, microhardness and wear resistance of the coatings were investigated. The thickness of the coatings was also determined (8-10μm). Metallographic analyses, SEM (scanning electron microscopic) investigation, microhardness measurements by knoop method, wear resistance tests were carried out. The coatings with and without heat treatment at 290℃, 6 h were tested. Duplication of microhardness value and improvement of the coating's properties of heat treated coatings were observed.
文摘The protective effect of modified nanodiamonds (MND) under the action of cobalt and nickel ions on the skin of Guinea pigs was shown. At the action of chromium ions on the skin of animals, the protective effect of MND was not found. The differences are related to different adsorption properties of MND to the investigated colored metal ions. It is shown in vitro that MND can adsorb ions of cobalt and nickel and don’t bind ions of chromium from aqueous medium. The perspectives using of MND as a new drug for the prevention allergic dermatitis caused by action of bivalent ions of metals are discussed.
文摘The effect of Chemical Mechanical Modification (CMM) and dispersants on the ζ potential of nanodiamond particles in aqueous system and the influence of the ultrasonic or shearing techniques on its size distribution were studied CMM and the addition of dispersants AD 2 and AD 8 improve the stability of its suspension With ultrasonic time prolonged, the mean average size of nanodiamond decreases, while with the prolongation of shearing time, its mean size decreases first, then increases a little In the speed range used, the mean size decreases with the rising speed If the whole ultrasonic time kept constant, it is better to add the dispersants before
文摘The methods of chemical-mechanical treatments (CMT) were utilized for surface modification of nanodiamond in aqueous medium, and a considerably stable suspension system was thus obtained. The size of all the particles in the provided system was less than 100 nm with a narrow distribution and excellent stability, and no obvious change of particle crystal structure after the treatments was observed. The mechanism of the treatments was also discussed. The results show that, because of mechanical treatment effect, addition of ionic surfactants and inorganic regulators, the ζ-potential of nanodiamond shifts upwards during the treatments, and the composition of surface functional groups changes. Carboxyl and hydroxyl groups are intensified after the surface modification, which may contribute to the improvement of dispersion and stability. Meanwhile, the addition of non-ionic polymer can also benefit the suspension stability.
文摘Well-dispersed nanodiamond(ND) aqueous suspensions in both acidic and alkaline environments is prepared by mechanochemical treatment. All the ND particles in the suspensions are smaller than 100nm in dimension with a narrow size distribution, and no destabilization phenomena were detected in a duration of more than one year. Stable dispersion of ND in the media may attributed to the strong electrostatic repulsion between particles because of the adsorption of dispersants, while mechanical forces may strengthen this adsorption reaction. Good adaptability and applicability of the suspensions to the change of ND concentration and surrounding temperature are observed, and improved performances of ND diamonds are obtained when used in ultrafine polishing and composite plating.
基金funded by National Natural Science Foundation of China(Nos.52102162 and 11975205)Guangdong Basic and Applied Basic Research Foundation(Nos.2022A1515011794 and 2020B1515120048)+1 种基金the Young Talents in Higher Education of Guangdong(No.2021KQNCX273)the support from Jiangsu Science and Technology Programme-YoungScholar(BK20200251)。
文摘Benefiting from its surface-rich functional groups,eco-friendliness,impressive electrochemical properties,excellent light absorption,structural tunability at the atomic/morphological level,and ultra-high stability under harsh conditions,nanodiamond has emerged as a promising carbon-based non-metallic material in the field of energy conversion such as electrocatalysis and photocatalysis.Furthermore,nanodiamond,as a new generation of green catalysts,can overcome the poisoning of catalysts by complex pollutants in advanced oxidation processes,thus effectively removing organic matter from water,which is unparalleled in reducing the cost of water purification and avoiding secondary cross-contamination of water by traditional heavy metal-based catalysts.Here,we review the research and development of nanodiamonds as major electrocatalysts and photocatalysts for energy conversion and for air/water treatment for environmental remediation.The relevant properties,trimming strategy,mechanistic understanding,and design principles of nanodiamond as a catalyst are described,as well as the challenges and prospects of this emerging field.