The idea of adding reinforcing materials, or fillers, to polymers has been around for many decades. The reason for the creation of polymer composite materials came about due of the need for materials with specific pro...The idea of adding reinforcing materials, or fillers, to polymers has been around for many decades. The reason for the creation of polymer composite materials came about due of the need for materials with specific properties for specific applications. For example, composite materials are unique in their ability to allow brittle and ductile materials to become softer and stronger. It is expected that good tribological properties can be obtained for polymers filled with nano-scale fillers. A soft plastic can become harder and stronger by the addition of a light weight high stiffness material. In the present work, the effect of adding different percentages of carbon nano-particulates to polystyrene (PS) on the mechanical properties of nano-composites produced was investigated. Based on the experimental observations, it was found that as the percentage of the carbon nano-particulates (CNPS) increased hardness increased and consequently friction coefficient remarkably decreased.展开更多
<strong>Background:</strong> We aimed to investigate the ability of carbon nanoparticles to identify parathyroid glands with vasculature during thyroid surgery. <strong>Material and methods:</stro...<strong>Background:</strong> We aimed to investigate the ability of carbon nanoparticles to identify parathyroid glands with vasculature during thyroid surgery. <strong>Material and methods:</strong> Totally 42 patients with various thyroid diseases were selected for the prospective research of carbon nanoparticle injection used in thyroidectomy. Another 42 patients without receiving carbon nanoparticle injection were selected as the control group. All cases underwent total or subtotal bilateral thyroidectomy. Before the ligation of the superior and inferior poles of the thyriod lobes, 0.1 mL of a carbon nanoparticle suspension was injected into the two poles. Important tissues such as the recurrent laryngeal nerve, parathyroid gland with blood supply and the inferior thyroid artery were identified and protected. <strong>Results:</strong> The parathyroid glands with vasculature were not stained and thus remained the primary color in all cases, while abnormal thyroid tissues were stained black. After 5 minutes, thyroid lobes were injected with the carbon nanoparticle suspension and the original color of parathyroid glands was unchanged. Even the parathyroids with blood supply can be identified and protected. The number of parathyroid glands for autotransplantation was one in the test group and six in the control group. At one day after the thyroid surgery, hypocalcemia became detectable in four patients of the test group and in five of the control group. Twenty-four instances of hypoparathyroidism occurred at 1 day after surgery in the control group, while ten instances in the test group. <strong>Conclusion:</strong> Intraoperatvie carbon nanoparticle suspension injection is an effective and safe technique for guiding thyroid surgery. The carbon nanoparticle suspension plays an important role in identifying the vasculatural parathyroid glands, while protecting the physiologic function of the parathyroid glands during surgery.展开更多
X-Ray Absorption Spectroscopy (XAS) on the carbon K edge of carbon nanostructures (nanotubes, nanofibers, nanowalls) is reported here. They are grown on plain SiO2 (8 nm thick)/Si(100) substrates by a Plasma and Hot F...X-Ray Absorption Spectroscopy (XAS) on the carbon K edge of carbon nanostructures (nanotubes, nanofibers, nanowalls) is reported here. They are grown on plain SiO2 (8 nm thick)/Si(100) substrates by a Plasma and Hot Filaments-enhanced Catalytic Chemical Vapor Deposition (PE HF CCVD) process. The morphology and the nature of these carbon nanostructures are characterized by SEM, TEM and Raman spectroscopy. According to conditions of catalyst preparation and DC HF CCVD process, carbon nanotubes (CNTs), carbon nanofibers (CNFs), carbon nanowalls (CNWs), carbon nanoparticles (CNPs) with different orientation of the graphene plans or shells can be prepared. From the angular dependence of the incident light and geometrical morphology of the nanostructures, wide variations of the C K-edge intensity of the transitions to the empty π* and σ* states occur. A full lineshape analysis of the XAS spectra has been carried out using a home-made software, allowing estimating the relative proportion of π* and σ* transitions. A geometrical model of the angular dependence with the incidence angle of the light and the morphology of the carbon nanostructures is derived. With normalization to the HOPG (Highly Oriented Pyrolytic Graphite graphite) reference case, a degree of alignment can be extracted which is representative of the localized orientation of the graphitic carbon π bonds, accounting not only for the overall orientation, but also for local defects like impurities incorporation, structural defects ... This degree of alignment shows good agreement with SEM observations. Thus CNTs films display degrees of alignment around 50%, depending on the occurrence of defects in the course of the growth, whereas no special alignment can be detected with CNFs and CNPs, and a weak one (about 20%) is detected on CNWs.展开更多
The astonishingly distinct lubricity difference between the ionic liquid modified carbon nanoparticles grafted by anion and cation moieties(A-g-CNPs and C-g-CNPs)was well established as additives of polyethylene glyco...The astonishingly distinct lubricity difference between the ionic liquid modified carbon nanoparticles grafted by anion and cation moieties(A-g-CNPs and C-g-CNPs)was well established as additives of polyethylene glycol(PEG200).The peripheral anion moieties and positively charged inner parts of C-g-CNPs could successively absorb onto the friction interfaces by electrostatic interactions to form the organic-inorganic electric double layer structures,tremendously boosting the lubricity of PEG200.Contrarily,the preferentially electrostatic adsorption of negatively charged inner parts but repulsion of the peripheral cation moieties determined the weak embedded stability of A-g-CNPs between the friction interfaces,even impairing the lubricity of PEG200.This work can offer solidly experimental and theoretical guidance for designing and developing the high-performance nanoadditives modified by ionic molecules.展开更多
A simple （2×2） pixelated flexible infrared nanosensor array based on carbon nanoparticles （CNPs） was fabricated through a simple and low-cost flame method. By integrated with a micro controller unit, the sens...A simple （2×2） pixelated flexible infrared nanosensor array based on carbon nanoparticles （CNPs） was fabricated through a simple and low-cost flame method. By integrated with a micro controller unit, the sensor array could detect power density of incident infrared light in real-time. The mechanism for the superior infrared sensing property of the flexible sensor array based on CNP was also studied in detail in this work.展开更多
文摘The idea of adding reinforcing materials, or fillers, to polymers has been around for many decades. The reason for the creation of polymer composite materials came about due of the need for materials with specific properties for specific applications. For example, composite materials are unique in their ability to allow brittle and ductile materials to become softer and stronger. It is expected that good tribological properties can be obtained for polymers filled with nano-scale fillers. A soft plastic can become harder and stronger by the addition of a light weight high stiffness material. In the present work, the effect of adding different percentages of carbon nano-particulates to polystyrene (PS) on the mechanical properties of nano-composites produced was investigated. Based on the experimental observations, it was found that as the percentage of the carbon nano-particulates (CNPS) increased hardness increased and consequently friction coefficient remarkably decreased.
文摘<strong>Background:</strong> We aimed to investigate the ability of carbon nanoparticles to identify parathyroid glands with vasculature during thyroid surgery. <strong>Material and methods:</strong> Totally 42 patients with various thyroid diseases were selected for the prospective research of carbon nanoparticle injection used in thyroidectomy. Another 42 patients without receiving carbon nanoparticle injection were selected as the control group. All cases underwent total or subtotal bilateral thyroidectomy. Before the ligation of the superior and inferior poles of the thyriod lobes, 0.1 mL of a carbon nanoparticle suspension was injected into the two poles. Important tissues such as the recurrent laryngeal nerve, parathyroid gland with blood supply and the inferior thyroid artery were identified and protected. <strong>Results:</strong> The parathyroid glands with vasculature were not stained and thus remained the primary color in all cases, while abnormal thyroid tissues were stained black. After 5 minutes, thyroid lobes were injected with the carbon nanoparticle suspension and the original color of parathyroid glands was unchanged. Even the parathyroids with blood supply can be identified and protected. The number of parathyroid glands for autotransplantation was one in the test group and six in the control group. At one day after the thyroid surgery, hypocalcemia became detectable in four patients of the test group and in five of the control group. Twenty-four instances of hypoparathyroidism occurred at 1 day after surgery in the control group, while ten instances in the test group. <strong>Conclusion:</strong> Intraoperatvie carbon nanoparticle suspension injection is an effective and safe technique for guiding thyroid surgery. The carbon nanoparticle suspension plays an important role in identifying the vasculatural parathyroid glands, while protecting the physiologic function of the parathyroid glands during surgery.
文摘X-Ray Absorption Spectroscopy (XAS) on the carbon K edge of carbon nanostructures (nanotubes, nanofibers, nanowalls) is reported here. They are grown on plain SiO2 (8 nm thick)/Si(100) substrates by a Plasma and Hot Filaments-enhanced Catalytic Chemical Vapor Deposition (PE HF CCVD) process. The morphology and the nature of these carbon nanostructures are characterized by SEM, TEM and Raman spectroscopy. According to conditions of catalyst preparation and DC HF CCVD process, carbon nanotubes (CNTs), carbon nanofibers (CNFs), carbon nanowalls (CNWs), carbon nanoparticles (CNPs) with different orientation of the graphene plans or shells can be prepared. From the angular dependence of the incident light and geometrical morphology of the nanostructures, wide variations of the C K-edge intensity of the transitions to the empty π* and σ* states occur. A full lineshape analysis of the XAS spectra has been carried out using a home-made software, allowing estimating the relative proportion of π* and σ* transitions. A geometrical model of the angular dependence with the incidence angle of the light and the morphology of the carbon nanostructures is derived. With normalization to the HOPG (Highly Oriented Pyrolytic Graphite graphite) reference case, a degree of alignment can be extracted which is representative of the localized orientation of the graphitic carbon π bonds, accounting not only for the overall orientation, but also for local defects like impurities incorporation, structural defects ... This degree of alignment shows good agreement with SEM observations. Thus CNTs films display degrees of alignment around 50%, depending on the occurrence of defects in the course of the growth, whereas no special alignment can be detected with CNFs and CNPs, and a weak one (about 20%) is detected on CNWs.
基金financially supported by the National Natural Science Foundation of China(No.51975493).
文摘The astonishingly distinct lubricity difference between the ionic liquid modified carbon nanoparticles grafted by anion and cation moieties(A-g-CNPs and C-g-CNPs)was well established as additives of polyethylene glycol(PEG200).The peripheral anion moieties and positively charged inner parts of C-g-CNPs could successively absorb onto the friction interfaces by electrostatic interactions to form the organic-inorganic electric double layer structures,tremendously boosting the lubricity of PEG200.Contrarily,the preferentially electrostatic adsorption of negatively charged inner parts but repulsion of the peripheral cation moieties determined the weak embedded stability of A-g-CNPs between the friction interfaces,even impairing the lubricity of PEG200.This work can offer solidly experimental and theoretical guidance for designing and developing the high-performance nanoadditives modified by ionic molecules.
文摘A simple （2×2） pixelated flexible infrared nanosensor array based on carbon nanoparticles （CNPs） was fabricated through a simple and low-cost flame method. By integrated with a micro controller unit, the sensor array could detect power density of incident infrared light in real-time. The mechanism for the superior infrared sensing property of the flexible sensor array based on CNP was also studied in detail in this work.
基金Project supported by the National Natural Science Foundation of China(Nos.41303093,41222025,and 41273138)the Program for New Century Excellent Talents in University of Ministry of Education of Chinathe Recruitment Program of HighlyQualified Scholars in Yunnan Province(No.2010CI109),China
