light barrier
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2022 ◽  
Vol 2148 (1) ◽  
pp. 012004
Author(s):  
Zhong Guan

Abstract There discovered the maximum possible magnetic induction in nature, equal to the magnetic induction at the poles of an electron’s spin, When the spin magnetic moments of two electrons are close to each other, they act on each other with the maximum possible magnetic induction, and finally entered the maximally entangled state after the energy drops. By this time, the spin magnetic moments on both sides situated in anti-parallel, between them there existed four invisible magnetic circuit, and each magnetic circuit just contain a fluxon. No matter how far the distance between the spins, owing to the inalienability of fluxon, no magnetic flux leakage (coupling degree 100%), so these four magnetic circuit will always existed, maintaining the maximally entangled state system immutably. This is the material basis for the entangled state to be existed, nothing to do with “spooky action at a distance”. In this paper, a visual schematic diagram has drawn to describe these, and the magnetic force state, force relationship and “light barrier” problem are analyzed.


Membranes ◽  
2021 ◽  
Vol 12 (1) ◽  
pp. 46
Author(s):  
María Carpintero ◽  
Ismael Marcet ◽  
Manuel Rendueles ◽  
Mario Díaz

Polylactic acid (PLA) is known to be one of the most extensively used biodegradable thermoplastic polyesters, with the potential to replace conventional petroleum-based packaging materials; however, the low flexibility of films prepared using PLA has limited the applications of this biopolymer. In this study, in order to improve the mechanical properties of PLA films and to provide them with antioxidant properties, egg yolk oil was used as a biobased plasticizer. For this purpose, PLA films with increasing concentrations of egg yolk oil were prepared and the effects of this oil on the light transmission, transparency, colour, water vapour permeability, solubility, antioxidant activity and mechanical properties of the films were characterized. In addition, electron microscopy of the structure of the transverse section of the films was also performed. Results showed that the formulations with higher concentrations of egg yolk oil increased the films’ elasticity, and their light barrier and antioxidant properties. Finally, in order to test the films as a packaging material for food applications, extra virgin olive oil and resveratrol, both photosensitive compounds, were packed and exposed to ambient light. Overall, the results show the potential of egg yolk oil as an environmentally friendly plasticizer that can improve the flexibility of PLA films and provide them with additional photoprotective properties.


2021 ◽  
Author(s):  
Andreas Wieser ◽  
Jessica Beyerl ◽  
Albrecht von Brunn ◽  
Vincent Rieker ◽  
Marcus Rieker ◽  
...  

Background: The SARS-CoV-2 pandemic demonstrated the vulnerability of our societies to aerosol transmitted pathogens. With no less than 260mio known cases and >5mio deaths, SARS-CoV-2 is a global catastrophe leading to human and economic losses unprecedented in recent history. Thus, effective methods to limit the spread of aerosol transmitted pathogens are needed. Universal masking and curfew laws are effective but no permanent solution. Methods: A mass producible LED light source emitting homogeneous parallel UV-C light was used as a light-barrier to block the spread of infectious aerosols. In an aerosol test channel, Gram-negative and Gram-positive bacteria as well as coronavirus were nebulized and inactivation rates were determined. Findings: With air speeds of 0.1ms-1 an exposure time of 1s in the UV-C light is obtained. Reduction in CFU for E. coli was >3log10 and for S. aureus ~2.8log10. Plug-forming-units of the murine coronavirus (Mouse Hepatitis Virus, MHV) were reduced by about 3log10. Interpretation: The concept of a UV-C light barrier to ward off infectious aerosols if feasible and possible with a light element as described here. Coupled with sensor based activation/deactivation, such a technology could greatly reduce the transmission rates of aerosol transmitted pathogens while not disturbing natural human behaviour. This is an interesting technology allowing a new normal in societies after/with SARS-CoV-2.


Nanophotonics ◽  
2021 ◽  
Vol 0 (0) ◽  
Author(s):  
John Pendry ◽  
Paloma Huidobro ◽  
Mario Silveirinha ◽  
Emanuele Galiffi

Abstract We ask the question “what happens to Bloch waves in gratings synthetically moving at near the speed of light?”. First we define a constant refractive index (CRI) model in which Bloch waves remain well defined as they break the light barrier, then show their dispersion rotating through 360° from negative to positive and back again. Next we introduce the effective medium approximation (EMA) then refine it into a 4-wave model which proves to be highly accurate. Finally using the Bloch waves to expand a pulse of light we demonstrate sudden inflation of pulse amplitude combined with reversal of propagation direction as a luminal grating is turned on.


Polymers ◽  
2021 ◽  
Vol 13 (20) ◽  
pp. 3472
Author(s):  
Smarak Bandyopadhyay ◽  
Tomáš Sáha ◽  
Daniel Sanétrník ◽  
Nabanita Saha ◽  
Petr Sáha

There is a gap in the literature for the preparation of agar-xanthan gum-carboxymethyl cellulose-based films by thermo compression methods. The present work aims to fill this gap by blending the polysaccharides in a plastograph and preparation of films under high pressure and temperature for a short duration of time. The pivotal aim of this work is also to know the effect of different mixing conditions on the physical, chemical, mechanical and thermal properties of the films. The films are assessed based on results from microscopic, infrared spectroscopic, permeability (WVTR), transmittance, mechanical, rheological and thermogravimetric analysis. The results revealed that the mixing volume and mixing duration had negative effects on the films’ transparency. WVTR was independent of the mixing conditions and ranged between 1078 and 1082 g/m2.d. The mixing RPM and mixing duration had a positive effect on the film tensile strength. The films from the blends mixed at higher RPM for a longer time gave elongation percentage up to 78%. Blending also altered the crystallinity and thermal behavior of the polysaccharides. The blend prepared at 80 RPM for 7 min and pressed at 140 °C showed better percent elongation and light barrier properties.


Polymers ◽  
2021 ◽  
Vol 13 (15) ◽  
pp. 2403
Author(s):  
Karina Dyasti Hari ◽  
Coralia V. Garcia ◽  
Gye-Hwa Shin ◽  
Jun-Tae Kim

Pectin-based antibacterial bionanocomposite films were prepared by crosslinking with calcium chloride (CaCl2) and mixing with zinc oxide nanoparticles (ZnO-NPs) at various concentrations (0.5%, 1%, and 1.5% w/w, based on pectin). Crosslinking with 1% CaCl2 significantly (p < 0.05) improved the tensile strength of the pectin films, although their elongation at break was decreased. The UV-light barrier property of the pectin/ZnO bionanocomposite films was significantly (p < 0.05) improved with increasing ZnO-NP concentrations. In addition, the bionanocomposite films incorporating 1.5% ZnO-NPs showed excellent antibacterial effects against both Escherichia coli and Staphylococcus aureus, inhibiting over 99% of the bacteria. Therefore, the developed crosslinked pectin/ZnO bionanocomposite films show great potential as active packaging materials with excellent UV-blocking and antibacterial properties.


Molecules ◽  
2020 ◽  
Vol 25 (23) ◽  
pp. 5563
Author(s):  
Luisa Bataglin Avila ◽  
Elis Regina Correa Barreto ◽  
Paloma Krolow de Souza ◽  
Bárbara De Zorzi Silva ◽  
Thamiris Renata Martiny ◽  
...  

This research investigated the bioactive potential of jaboticaba peel extract (JPE) and proposed an innovative material for food packaging based on carrageenan films incorporated with JPE. The extract was obtained through microwave assisted extraction (MAE) according to central composite rotational design and the optimized conditions showed a combined antimicrobial and antioxidant actions when the extraction process is accomplished at 80 °C and 1 min. The carrageenan film incorporated with JPE was manageable, homogeneous and the presence of JPE into film increased the thickness and improved the light barrier of the film. The results of solubility and mechanical properties did not show significant differences. The benefit of using MAE to improve the recovery of bioactive compounds was demonstrated and the carrageenan film with JPE showed a great strategy to add additives into food packaging.


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