We propose a simple and efficient method that uses a single focused hybrid vector beam to confine metallic Rayleigh particles at multiple positions.We study the force mechanisms of multiple trapping by analyzing the g...We propose a simple and efficient method that uses a single focused hybrid vector beam to confine metallic Rayleigh particles at multiple positions.We study the force mechanisms of multiple trapping by analyzing the gradient and scattering forces.It is observed that the wavelength and topological charges of the hybrid vector beam regulate the trapping positions and number of optical trap sites.The proposed method can be implemented easily in three-dimensional space, and it facilitates both trapping and organization of particles.Thus, it can provide an effective and controllable means for nanoparticle manipulation.展开更多
Optical tweezers use the radiation pressure to trap and manipulate the microscopic particles. Using various algorithms multiple traps are being formed which can trap a number of particles simultaneously. In contrast t...Optical tweezers use the radiation pressure to trap and manipulate the microscopic particles. Using various algorithms multiple traps are being formed which can trap a number of particles simultaneously. In contrast to multiple traps, many particles can be trapped at a single trap position. It is known that when two or more particles are trapped in a single trap they align themselves in axial direction and it appears as if only one particle is trapped. We present a study of the dependence of the optical trapping force on the number of particles in a single trap using equipartition method;the study was carried out for particles of different sizes. The trapping force was first found to increase then decrease with number of particles in trap for all particle sizes. We feel that our studies will be useful in applications of optical tweezers involving trapping of multiple particles in a single trap.展开更多
建立了多次顶空-捕集阱捕集/气相色谱质谱联用-基质加标校正曲线测定皮革中的挥发性有机物的方法。在10 m L无挥发性有机物的试剂水中加入1g皮革样品和2 g NaCl,顶空时间30 min,温度80℃,捕集阱加压循环3次。气质联用法分析皮革中的挥...建立了多次顶空-捕集阱捕集/气相色谱质谱联用-基质加标校正曲线测定皮革中的挥发性有机物的方法。在10 m L无挥发性有机物的试剂水中加入1g皮革样品和2 g NaCl,顶空时间30 min,温度80℃,捕集阱加压循环3次。气质联用法分析皮革中的挥发性有机物,采用DB-624（60 m×0.25 mm×1.4μm）的色谱柱分离挥发性有机物,并采用基质加标校正标准曲线对目标化合物进行定量。目标化合物在1~400μg/L或20~400μg/L的内线性关系良好,R在0.995~0.999之间,不同浓度的加标回收率在80.8%~125%之间,相对标准偏差在1.3%~16%之间,检出限在0.08~21.7μg/kg。展开更多
A class of n-dimensional ODEs with up to n feedbacks from the n’th variable is analysed. The feedbacks are represented by non-specific, bounded, non-negative C<sup>1</sup> functions. The main result is th...A class of n-dimensional ODEs with up to n feedbacks from the n’th variable is analysed. The feedbacks are represented by non-specific, bounded, non-negative C<sup>1</sup> functions. The main result is the formulation and proof of an easily applicable criterion for existence of a globally stable fixed point of the system. The proof relies on the contraction mapping theorem. Applications of this type of systems are numerous in biology, e.g., models of the hypothalamic-pituitary-adrenal axis and testosterone secretion. Some results important for modelling are: 1) Existence of an attractive trapping region. This is a bounded set with non-negative elements where solutions cannot escape. All solutions are shown to converge to a “minimal” trapping region. 2) At least one fixed point exists. 3) Sufficient criteria for a unique fixed point are formulated. One case where this is fulfilled is when the feedbacks are negative.展开更多
Metal-Oxide-Semiconductor Capacitance-Voltage （MOSCV） characteristics containing giant carrier trapping capacitances from 3-charge-state or 2-energy-level impurities are presented for not-doped, n-doped, p- doped an...Metal-Oxide-Semiconductor Capacitance-Voltage （MOSCV） characteristics containing giant carrier trapping capacitances from 3-charge-state or 2-energy-level impurities are presented for not-doped, n-doped, p- doped and compensated silicon containing the double-donor sulfur and iron, the double-acceptor zinc, and the amphoteric or one-donor and one-acceptor gold and silver impurities. These impurities provide giant trapping ca- pacitances at trapping energies from 200 to 800 meV （50 to 200 THz and 6 to 1.5 μm）, which suggest potential sub-millimeter, far-infrared and spin electronics applications.展开更多
基金Project supported by the National Natural Science Foundation of China(Grant Nos.11604050,91636109,61575041,and 61875242)the Fundamental Research Funds for the Central Universities at Xiamen University,China(Grant No.20720190057)+3 种基金the Natural Science Foundation of Fujian Province of China for Distinguished Young Scientists(Grant No.2015J06002)the Program for New Century Excellent Talents in University of China(Grant No.NCET-13-0495)the Science and Technology Planning Project of Guangdong Province,China(Grant No.2016B010113004)the Natural Science Foundation of Guangdong Province,China(Grant Nos.2015A030310296 and 2018A030313347)
文摘We propose a simple and efficient method that uses a single focused hybrid vector beam to confine metallic Rayleigh particles at multiple positions.We study the force mechanisms of multiple trapping by analyzing the gradient and scattering forces.It is observed that the wavelength and topological charges of the hybrid vector beam regulate the trapping positions and number of optical trap sites.The proposed method can be implemented easily in three-dimensional space, and it facilitates both trapping and organization of particles.Thus, it can provide an effective and controllable means for nanoparticle manipulation.
文摘Optical tweezers use the radiation pressure to trap and manipulate the microscopic particles. Using various algorithms multiple traps are being formed which can trap a number of particles simultaneously. In contrast to multiple traps, many particles can be trapped at a single trap position. It is known that when two or more particles are trapped in a single trap they align themselves in axial direction and it appears as if only one particle is trapped. We present a study of the dependence of the optical trapping force on the number of particles in a single trap using equipartition method;the study was carried out for particles of different sizes. The trapping force was first found to increase then decrease with number of particles in trap for all particle sizes. We feel that our studies will be useful in applications of optical tweezers involving trapping of multiple particles in a single trap.
文摘建立了多次顶空-捕集阱捕集/气相色谱质谱联用-基质加标校正曲线测定皮革中的挥发性有机物的方法。在10 m L无挥发性有机物的试剂水中加入1g皮革样品和2 g NaCl,顶空时间30 min,温度80℃,捕集阱加压循环3次。气质联用法分析皮革中的挥发性有机物,采用DB-624（60 m×0.25 mm×1.4μm）的色谱柱分离挥发性有机物,并采用基质加标校正标准曲线对目标化合物进行定量。目标化合物在1~400μg/L或20~400μg/L的内线性关系良好,R在0.995~0.999之间,不同浓度的加标回收率在80.8%~125%之间,相对标准偏差在1.3%~16%之间,检出限在0.08~21.7μg/kg。
文摘A class of n-dimensional ODEs with up to n feedbacks from the n’th variable is analysed. The feedbacks are represented by non-specific, bounded, non-negative C<sup>1</sup> functions. The main result is the formulation and proof of an easily applicable criterion for existence of a globally stable fixed point of the system. The proof relies on the contraction mapping theorem. Applications of this type of systems are numerous in biology, e.g., models of the hypothalamic-pituitary-adrenal axis and testosterone secretion. Some results important for modelling are: 1) Existence of an attractive trapping region. This is a bounded set with non-negative elements where solutions cannot escape. All solutions are shown to converge to a “minimal” trapping region. 2) At least one fixed point exists. 3) Sufficient criteria for a unique fixed point are formulated. One case where this is fulfilled is when the feedbacks are negative.
基金Supported by the Xiamen University,China,and the CISAH Associates(CTSA),founded by the late Linda Su-Nan Chang Sah
文摘Metal-Oxide-Semiconductor Capacitance-Voltage （MOSCV） characteristics containing giant carrier trapping capacitances from 3-charge-state or 2-energy-level impurities are presented for not-doped, n-doped, p- doped and compensated silicon containing the double-donor sulfur and iron, the double-acceptor zinc, and the amphoteric or one-donor and one-acceptor gold and silver impurities. These impurities provide giant trapping ca- pacitances at trapping energies from 200 to 800 meV （50 to 200 THz and 6 to 1.5 μm）, which suggest potential sub-millimeter, far-infrared and spin electronics applications.
