15 research outputs found
What is the meaning of physical quantity in the expression of photon energy ?
It is well known that, for an incident light of not so high intensity and in
a certain range of frequency, the stopping voltage of photoelectric effect is
independent of the intensity but dependent on the frequency of the light, which
is described by the equation , where is the stopping
voltage, is the Planck constant, is the frequency of incident light,
is the electron charge, and is the work function. It means that the
larger the frequency of incident light, the higher the stopping voltage is.
However, the present experiment finds that for a non-monochromatic incident
light, the stopping voltage is not determined by the maximum frequency
component of the incident light, but by the maximum center frequency of all the
wave train components (with different center frequencies) involved in the
incident light, that is to say, in the photon energy expression ,
physical quantity does not refer to the frequency of a monochromatic
light, but represents the center frequency of a wave train spectrum. The
spectral bandwidth of a wave train component can be as large as 122 nm in
visible and near-infrared region. This should arouse more attention in the
study of energy exchange between light and matter.Comment: 7pagers,4figure
Observation of a push force on the end face of a nm fiber taper exerted by outgoing light
There are two different proposals for the momentum of light in a transparent
dielectric of refractive index n: Minkowski's version nE/c and Abrahm's version
E/(nc), where E and c are the energy and vacuum speed of light, respectively.
Despite many tests and debates over nearly a century, momentum of light in a
transparent dielectric remains controversial. In this Letter, we report a
direct observation of the inward push force on the end face of a free nm fiber
taper exerted by the outgoing light. Our results clearly support Abraham
momentum. Our experiment also indicates an inward surface pressure on a
dielectric exerted by the incident light, different from the commonly
recognized pressure due to the specular reflection. Such an inward surface
pressure by the incident light may be useful for precise design of the
laser-induced inertially-confined fusion.Comment: 9 pages, 3 figures;Accepted for publication as a Letter in Physical
Review Letters(CODE: LP11093
Engineering pressure retarded osmosis membrane bioreactor (PRO-MBR) for simultaneous water and energy recovery from municipal wastewater
Osmotic membrane bioreactors (OMBR) have gained increasing interest in wastewater treatment and reclamation due to their high product water quality and fouling resistance. However, high energy consumption (mostly by draw solution recovery) restricted the wider application of OMBR. Herein, we propose a novel pressure retarded osmosis membrane bioreactor (PRO-MBR) for improving the economic feasibility. In comparison with conventional FO-MBR, PRO-MBR exhibited similar excellent contaminants removal performance and comparable water flux. More importantly, a considerable amount of energy can be recovered by PRO-MBR (4.1 kWh/100 m2·d), as a result of which, 10.02% of the specific energy consumption (SEC) for water recovery was reduced as compared with FO-MBR (from 1.42 kWh/m3 to 1.28 kWh/m3). Membrane orientation largely determined the performance of PRO-MBR, higher power density was achieved in AL-DS orientation (peak value of 3.4 W/m2) than that in AL-FS orientation (peak value of 1.4 W/m2). However, PRO-MBR suffered more severe and complex membrane fouling when operated in AL-DS orientation, because the porous support layer was facing sludge mixed liquor. Further investigation revealed fouling was mostly reversible for PRO-MBR, it exhibited similar flux recoverability (92.4%) to that in FO-MBR (95.1%) after osmotic backwash. Nevertheless, flux decline due to membrane fouling is still a restricting factor to power generation of PRO-MBR, its power density was decreased by 38.2% in the first 60 min due to the formation of fouling. Overall, in perspective of technoeconomic feasibility, the PRO-MBR demonstrates better potential than FO-MBR in wastewater treatment and reclamation and deserves more research attention in the future.This work was supported by the National Natural Science Foundation of China [grant number 51978312]; the Six Major Talent Peaks of Jiangsu Province [grant number 2018-JNHB-014]; and the Program to Cultivate Middle-aged and Young Science Leaders of Colleges and Universities of Jiangsu Province
Engineering pressure retarded osmosis membrane bioreactor (PRO-MBR) for simultaneous water and energy recovery from municipal wastewater
Osmotic membrane bioreactors (OMBR) have gained increasing interest in wastewater treatment and reclamation due to their high product water quality and fouling resistance. However, high energy consumption (mostly by draw solution recovery) restricted the wider application of OMBR. Herein, we propose a novel pressure retarded osmosis membrane bioreactor (PRO-MBR) for improving the economic feasibility. In comparison with conventional FO-MBR, PRO-MBR exhibited similar excellent contaminants removal performance and comparable water flux. More importantly, a considerable amount of energy can be recovered by PRO-MBR (4.1 kWh/100 m2·d), as a result of which, 10.02% of the specific energy consumption (SEC) for water recovery was reduced as compared with FO-MBR (from 1.42 kWh/m3 to 1.28 kWh/m3). Membrane orientation largely determined the performance of PRO-MBR, higher power density was achieved in AL-DS orientation (peak value of 3.4 W/m2) than that in AL-FS orientation (peak value of 1.4 W/m2). However, PRO-MBR suffered more severe and complex membrane fouling when operated in AL-DS orientation, because the porous support layer was facing sludge mixed liquor. Further investigation revealed fouling was mostly reversible for PRO-MBR, it exhibited similar flux recoverability (92.4%) to that in FO-MBR (95.1%) after osmotic backwash. Nevertheless, flux decline due to membrane fouling is still a restricting factor to power generation of PRO-MBR, its power density was decreased by 38.2% in the first 60 min due to the formation of fouling. Overall, in perspective of technoeconomic feasibility, the PRO-MBR demonstrates better potential than FO-MBR in wastewater treatment and reclamation and deserves more research attention in the future.</p
Spin-orbit hybrid entanglement of photons and quantum contextuality (vol 82, 022115, 2010)
We demonstrate electromagnetic quantum states of single photons and of correlated photon pairs exhibiting ''hybrid'' entanglement between spin and orbital angular momentum. These states are obtained from entangled photon pairs emitted by spontaneous parametric down conversion by employing a q plate for coupling the spin and orbital degrees of freedom of a photon. Entanglement and contextual quantum behavior (that is also nonlocal, in the case of photon pairs) is demonstrated by the reported violation of the Clauser-Horne-Shimony-Holt inequality. In addition, a classical analog of the hybrid spin-orbit photonic entanglement is reported and discussed