Aug 2022 • Advanced Functional Materials
Naga Prathibha Jasti, Gennady E Shter, Yishay Feldman, Davide Raffaele Ceratti, Adi Kama, Isaac Buchine, Gideon S Grader, David Cahen
The environment humidity effects on performance of halide perovskites (HaPs), especially MAPbI3, are known. Nevertheless, it is hard to find direct experimental evidence of H2O in the bulk materials at the levels lower than that of Monohydrate (MAPbI3.H2O). Here, for the first time, direct experimental evidence of water being released from bulk (µm‐s deep) of MAPbI3 single crystal is reported. The thermogravimetric analysis coupled with mass spectrometry (TGA‐MS) of evolved gases is used to detect the MS signal of H2O from the penetrable depth and correlate it with the TGA mass loss due to H2O leaving the material. These measurements yield an estimate of the average H2O content of 1 H2O molecule per three MAPbI3 formula units (MAPbI3.0.33H2O). Under the relatively low temperature conditions no other evolved gases that can correspond to MAPbI3 decomposition products, are observed in the MS. In …
Show moreAug 2022 • Physical Review B
Jakob Bätge, Amikam Levy, Wenjie Dou, Michael Thoss
In this paper we explore the effects of nonadiabatic external driving on the dynamics of an electronic system coupled to two electronic leads and to a phonon mode, with and without damping. In the limit of slow driving, we establish nonadiabatic corrections to thermodynamic and transport quantities. In particular, we study the first-order correction to the work done by the driving, the charge current, and the vibrational excitation using a perturbative expansion. We then compare the results to the numerically exact hierarchical equations of motion (HEOM) approach. Furthermore, the HEOM analysis spans both the weak and strong system-bath coupling regime and the slow-and fast-driving limits. We show that the electronic friction and the nonadiabatic corrections to the charge current provide a clear indicator for the Franck-Condon effect and for nonresonant tunneling processes. We also discuss the validity of the …
Show moreAug 2022 • Viruses
Nofar Atari, K Shanmugha Rajan, Vaibhav Chikne, Smadar Cohen-Chalamish, Tirza Doniger, Odelia Orbaum, Avi Jacob, Inna Kalt, Shulamit Michaeli, Ronit Sarid
The nucleolus is a subnuclear compartment whose primary function is the biogenesis of ribosomal subunits. Certain viral infections affect the morphology and composition of the nucleolar compartment and influence ribosomal RNA (rRNA) transcription and maturation. However, no description of nucleolar morphology and function during infection with Kaposi’s sarcoma-associated herpesvirus (KSHV) is available to date. Using immunofluorescence microscopy, we documented extensive destruction of the nuclear and nucleolar architecture during the lytic reactivation of KSHV. This was manifested by the redistribution of key nucleolar proteins, including the rRNA transcription factor UBF. Distinct delocalization patterns were evident; certain nucleolar proteins remained together whereas others dissociated, implying that nucleolar proteins undergo nonrandom programmed dispersion. Significantly, the redistribution of UBF was dependent on viral DNA replication or late viral gene expression. No significant changes in pre-rRNA levels and no accumulation of pre-rRNA intermediates were found by RT-qPCR and Northern blot analysis. Furthermore, fluorescent in situ hybridization (FISH), combined with immunofluorescence, revealed an overlap between Fibrillarin and internal transcribed spacer 1 (ITS1), which represents the primary product of the pre-rRNA, suggesting that the processing of rRNA proceeds during lytic reactivation. Finally, small changes in the levels of pseudouridylation (Ψ) and 2′-O-methylation (Nm) were documented across the rRNA; however, none were localized to the functional domain. Taken together, our results suggest that …
Show moreAug 2022 • ACS applied materials & interfaces
Angela Gala Morena, Arnau Bassegoda, Michal Natan, Gila Jacobi, Ehud Banin, Tzanko Tzanov
In recent years, lignin has drawn increasing attention for different applications due to its intrinsic antibacterial and antioxidant properties, coupled with biodegradability and biocompatibility. However, chemical modification or combination with metals is usually required to increase its antimicrobial functionality and produce biobased added-value materials for applications wherein bacterial growth should be avoided, such as biomedical and food industries. In this work, a sonoenzymatic approach for the simultaneous functionalization and nanotransformation of lignin to prepare metal-free antibacterial phenolated lignin nanoparticles (PheLigNPs) is developed. The grafting of tannic acid, a natural phenolic compound, onto lignin was achieved by an environmentally friendly approach using laccase oxidation upon the application of high-intensity ultrasound to rearrange lignin into NPs. PheLigNPs presented higher …
Show moreAug 2022 • Optical Fiber Sensors, Th4. 67, 2022
Keren Shemer, Gil Bashan, Elad Zehavi, Hilel Hagai Diamandi, Alon Bernstein, Kavita Sharma, Yosef London, David Barrera, Salvador Sales, Avi Zadok
Forward Brillouin point sensing is demonstrated in a multi-core fiber. Acoustic waves are stimulated by light in one core and monitored using a grating in another. Measurements distinguish between ethanol and water outside the cladding.
Show moreAug 2022 • Current Opinion in Electrochemistry 36, 101107, 2022
Eran Avraham, Barak Shapira, Izaak Cohen, Doron Aurbach
The important phenomenon of electrical double layer (EDL) is often described by mathematical relations between surface charges, variation of electrostatic potentials with distance and distribution of ions across the interface between charged surfaces (or particles) and electrolyte solutions. A major advance was made in the last decade in understanding complex EDL relationships with an emphasis on nano-porous carbonaceous materials. These understandings were usually exploited for the interpretation of electro-sorption phenomena connected to capacitive deionization (CDI) processes. The aim of this short paper is to demonstrate, based on previous studies, how models of EDL in nano-porous carbons can be the basis for modification of carbonaceous materials for other applications, like sensors and energy extraction from salinity gradients.
Show moreAug 2022 • Micromachines
Ari Leshno, Avraham Kenigsberg, Heli Peleg-Levy, Silvia Piperno, Alon Skaat, Hagay Shpaisman
Various conditions cause dispersions of particulate matter to circulate inside the anterior chamber of a human eye. These dispersed particles might reduce visual acuity or promote elevation of intraocular pressure (IOP), causing secondary complications such as particle related glaucoma, which is a major cause of blindness. Medical and surgical treatment options are available to manage these complications, yet preventive measures are not currently available. Conceptually, manipulating these dispersed particles in a way that reduces their negative impact could prevent these complications. However, as the eye is a closed system, manipulating dispersed particles in it is challenging. Standing acoustic waves have been previously shown to be a versatile tool for manipulation of bioparticles from nano-sized extracellular vesicles up to millimeter-sized organisms. Here we introduce for the first time a novel method utilizing standing acoustic waves to noninvasively manipulate intraocular particles inside the anterior chamber. Using a cylindrical acoustic resonator, we show ex vivo manipulation of pigmentary particles inside porcine eyes. We study the effect of wave intensity over time and rule out temperature changes that could damage tissues. Optical coherence tomography and histologic evaluations show no signs of damage or any other side effect that could be attributed to acoustic manipulation. Finally, we lay out a clear pathway to how this technique can be used as a non-invasive tool for preventing secondary glaucoma. This concept has the potential to control and arrange intraocular particles in specific locations without causing any damage to …
Show moreAug 2022 • Proceedings of the National Academy of Sciences
Subhradeep Misra, Michael Stern, Vladimir Umansky, Israel Bar-Joseph
We show that a Bose–Einstein condensate consisting of dark excitons forms in GaAs coupled quantum wells at low temperatures. We find that the condensate extends over hundreds of micrometers, well beyond the optical excitation region, and is limited only by the boundaries of the mesa. We show that the condensate density is determined by spin-flipping collisions among the excitons, which convert dark excitons into bright ones. The suppression of this process at low temperature yields a density buildup, manifested as a temperature-dependent blueshift of the exciton emission line. Measurements under an in-plane magnetic field allow us to preferentially modify the bright exciton density and determine their role in the system dynamics. We find that their interaction with the condensate leads to its depletion. We present a simple rate-equations model, which well reproduces the observed temperature, power, and …
Show moreAug 2022 • ACS Applied Bio Materials
Akanksha Gupta, Moorthy Maruthapandi, Poushali Das, Arumugam Saravanan, Gila Jacobi, Michal Natan, Ehud Banin, John HT Luong, Aharon Gedanken
Considering the global spread of bacterial infections, the development of anti-biofilm surfaces with high antimicrobial activities is highly desired. This work unraveled a simple, sonochemical method for coating Cu2O nanoparticles (NPs) on three different flexible substrates: polyester (PE), nylon 2 (N2), and polyethylene (PEL). The introduction of Cu2O NPs on these substrates enhanced their surface hydrophobicity, induced ROS generation, and completely inhibited the growth of sensitive (Escherichia coli and Staphyloccocus aureus) and drug-resistant (MDR E. coli and MRSA) planktonic and biofilm. The experimental results confirmed that Cu2O-PE exhibited complete biofilm mass reduction ability for all four strains, whereas Cu2O-N2 showed more than 99% biomass inhibition against both drug-resistant and sensitive pathogens in 6 h. Moreover, Cu2O-PEL also indicated a 99.95, 97.73, 98.00, and 99.20 …
Show moreAug 2022 • ACS nano
Channa Shapira, Daniel Itshak, Hamootal Duadi, Yifat Harel, Ayelet Atkins, Anat Lipovsky, Ronit Lavi, Jean Paul Lellouche, Dror Fixler
Carbon-based nanoparticles (NPs) are widely used in nanotechnology. Among them, nanodiamonds (NDs) are suitable for biotechnology and are especially interesting for skin delivery and topical treatments. However, noninvasive detection of NDs within the different skin layers or analyzing their penetration ability is complicated due to the turbid nature of the tissue. The iterative multiplane optical properties extraction (IMOPE) technique detects differences in the optical properties of the measured item by a phase-image analysis method. The phase image is reconstructed by the multiplane Gerchberg–Saxton algorithm. This technique, traditionally, detects differences in the reduced scattering coefficients. Here, however, due to the actual size of the NDs, the IMOPE technique’s detection relies on absorption analysis rather than relying on scattering events. In this paper, we use the IMOPE technique to detect the …
Show moreAug 2022 • SPring-8/SACLA Research Report
Priyanka Chakraborti, Ozgur Culfa, Matthias Fuchs, Johann Haber, David Reis, Sharon Shwartz, Kenji Tamasaku, Samuel Teitelbaum
The goal of the experiment was to investigate higher-order X-ray-optical sum-frequency generation (XSFG) as a means to study the dynamics of linear and nonlinear optically-induced local polarization effects in solids with Angstrom resolution. XSFG can be used as time-resolved atomic-scale probe of the dynamics of optically induced charge densities. The ability to optically control carrier dynamics in samples at the microscopic scale has the potential to become the basis of ultrafast optical switching of currents and future petahertz optoelectronic devices.
Show moreAug 2022 • Optica 9 (3), 273-279, 2022
Marc Jankowski, Nayara Jornod, Carsten Langrock, Boris Desiatov, Alireza Marandi, Marko Lončar, Martin M Fejer
We use dispersion-engineered PPLN nanowaveguides to demonstrate opti-cal parametric amplification without either temporal walk-off or group velocity dispersion. These quasi-static devices achieve large gains (> 145 dB/cm) across> 900 nanometers using picojoules of pump pulse energy.
Show moreAug 2022 • Journal of Chemical Theory and Computation
Khadiza Begam, Lilian Cohen, Gil Goobes, Barry D Dunietz
Nuclear magnetic resonance (NMR) properties of solvated molecules are significantly affected by the solvent. We, therefore, employ a polarization consistent framework that efficiently addresses the solvent polarizing environment effects. Toward this goal a dielectric screened range separated hybrid (SRSH) functional is invoked with a polarizable continuum model (PCM) to properly represent the orbital gap in the condensed phase. We build on the success of range separated hybrid (RSH) functionals to address the erroneous tendency of traditional density functional theory (DFT) to collapse the orbital gap. Recently, the impact of RSH that properly opens up the orbital gap in gas-phase calculations on NMR properties has been assessed. Here, we report the use of SRSH-PCM that produces properly solute orbital gaps in calculating isotropic nuclear magnetic shielding and chemical shift parameters of molecular …
Show moreAug 2022 • 2022 47th International Conference on Infrared, Millimeter and Terahertz …, 2022
N Lander Gower, S Piperno, A Albo
We have studied the effect of doping on the temperature performance of a split-well (SW) direct-phonon (DP) terahertz (THz) quantum-cascade laser (QCL) scheme supporting a clean three-level system. We expected to obtain a similar improvement in the temperature performance to that observed in resonant-phonon (RP) schemes after increasing the carrier concentration from To our surprise, in the devices we checked, the results show the contrary. However, we observed a significant increase in gain broadening and a reduction in the dephasing time as the doping and temperature increased. We attribute these effects to enhanced ionized-impurity scattering (IIS). The observation and study of effects related to dephasing included in our experimental work have previously only been possible via simulation.
Show moreAug 2022 • Journal of Chemical Theory and Computation
Khadiza Begam, Lilian Cohen, Gil Goobes, Barry D Dunietz
Nuclear magnetic resonance (NMR) properties of solvated molecules are significantly affected by the solvent. We, therefore, employ a polarization consistent framework that efficiently addresses the solvent polarizing environment effects. Toward this goal a dielectric screened range separated hybrid (SRSH) functional is invoked with a polarizable continuum model (PCM) to properly represent the orbital gap in the condensed phase. We build on the success of range separated hybrid (RSH) functionals to address the erroneous tendency of traditional density functional theory (DFT) to collapse the orbital gap. Recently, the impact of RSH that properly opens up the orbital gap in gas-phase calculations on NMR properties has been assessed. Here, we report the use of SRSH-PCM that produces properly solute orbital gaps in calculating isotropic nuclear magnetic shielding and chemical shift parameters of molecular …
Show moreAug 2022 • Physical Review Letters
Lior Zarfaty, Eli Barkai, David A Kessler
Extreme value (EV) statistics of correlated systems are widely investigated in many fields, spanning the spectrum from weather forecasting to earthquake prediction. Does the unavoidable discrete sampling of a continuous correlated stochastic process change its EV distribution? We explore this question for correlated random variables modeled via Langevin dynamics for a particle in a potential field. For potentials growing at infinity faster than linearly and for long measurement times, we find that the EV distribution of the discretely sampled process diverges from that of the full continuous dataset and converges to that of independent and identically distributed random variables drawn from the process’s equilibrium measure. However, for processes with sublinear potentials, the long-time limit is the EV statistics of the continuously sampled data. We treat processes whose equilibrium measures belong to the three EV …
Show moreAug 2022 • IEEE Photonics Journal
Ariel Ashkenazy, Racheli Ron, Tchiya Zar, Hannah Aharon, Adi Salomon, Dror Fixler, Eliahu Cohen
Two-photon interactions of entangled-photon pairs with metallic nanoparticles (NPs) can be enhanced by localized surface-plasmon resonance. Recently, we have described how the properties of this quantum light-matter interaction can be deduced from classical second-harmonic generation measurements performed using a reference-free hyper-Rayleigh scattering method. Herein, we report the results of such classical-light characterization measurements. We obtain a large hyperpolarizability for the NPs, present the dependence of the hyperpolarizability on the NPs' spectral features, and show a dipolar emission pattern for the second-harmonic signal. Our results can be used to optimize entangled-photon pair interactions with metallic NPs to enable first ever detection of this process. Moreover, these results suggest that NPs may be used as source for ultra-broadband entangled-photon pairs through nonphase …
Show moreAug 2022 • Physical Review Letters
Lior Zarfaty, Eli Barkai, David A Kessler
Extreme value (EV) statistics of correlated systems are widely investigated in many fields, spanning the spectrum from weather forecasting to earthquake prediction. Does the unavoidable discrete sampling of a continuous correlated stochastic process change its EV distribution? We explore this question for correlated random variables modeled via Langevin dynamics for a particle in a potential field. For potentials growing at infinity faster than linearly and for long measurement times, we find that the EV distribution of the discretely sampled process diverges from that of the full continuous dataset and converges to that of independent and identically distributed random variables drawn from the process’s equilibrium measure. However, for processes with sublinear potentials, the long-time limit is the EV statistics of the continuously sampled data. We treat processes whose equilibrium measures belong to the three EV …
Show moreAug 2022 • Catalysts 12 (8), 909, 2022
Amudhavalli Victor, Pankaj Sharma, Indra Neel Pulidindi, Aharon Gedanken
Levulinic acid (LA) is one of the top twelve chemicals listed by the US Department of Energy that can be derived from biomass. It serves as a building block and platform chemical for producing a variety of chemicals, fuels and materials which are currently produced in fossil based refineries. LA is a key strategic chemical, as fuel grade chemicals and plastic substitutes can be produced by its catalytic conversion. LA derivatisation to various product streams, such as alkyl levulinates via esterification, γ-valerolactone via hydrogenation and N-substituted pyrrolidones via reductive amination and many other transformations of commercial utility are possible owing to the two oxygen functionalities, namely, carbonyl and carboxyl groups, present within the same substrate. Various biomass feedstock, such as agricultural wastes, marine macroalgae, and fresh water microalgae were successfully converted to LA in high yields. Finding a substitute to mineral acid catalysts for the conversion of biomass to LA is a challenge. The use of an ultrasound technique facilitated the production of promising nano-solid acid catalysts including Ga salt of molybophosphoric acid and Ga deposited mordenite zeolite, with optimum amounts of Lewis and Bronsted acidities needed for the conversion of glucose to LA in high yields, being 56 and 59.9 wt.% respectively. Microwave irradiation technology was successfully utilized for the accelerated production of LA (53 wt.%) from glucose in a short duration of 6 min, making use of the unique synergistic catalytic activity of ZnBr 2 and HCl. View Full-Text
Show moreAug 2022 • Advanced Functional Materials
Tianju Fan, Wang Kai, Villa Krishna Harika, Cunsheng Liu, Amey Nimkar, Nicole Leifer, Sandipan Maiti, Judith Grinblat, Merav Nadav Tsubery, Xiaolang Liu, Meng Wang, Leimin Xu, Yuhao Lu, Yonggang Min, Netanel Shpigel, Doron Aurbach
The need for high power density cathodes for Li‐ion batteries can be fulfilled by application of a high charging voltage above 4.5 V. As lithium cobalt oxide (LCO) remains a dominant commercial cathode material, tremendous efforts are invested to increase its charging potential toward 4.6 V. Yet, the long‐term performance of high voltage LCO cathodes still remains poor. Here, an integrated approach combining the application of an aluminum fluoride coating and the use of electrolyte solutions comprising 1:1:8 mixtures of difluoroethylene:fluoroethylene carbonate:dimethyl carbonate and 1 m LiPF6 is reported. This results in superior behavior of LCO cathodes charged at 4.6 V with high initial capacity of 223 mAh g−1, excellent long‐term performance, and 78% capacity retention after 500 cycles. Impressive stability is also found at 450 °C with an initial capacity of 220 mAh g−1 and around 84% capacity retention …
Show moreAug 2022 • Optical Fiber Sensors, Tu1. 4, 2022
Elad Zehavi, Alon Bernstein, Gil Bashan, Yosef London, Hilel Hagai Diamandi, Kavita Sharma, Mirit Hen, A Zadok
Brillouin optical time domain analysis of coupling to cladding modes of standard, coated fiber is demonstrated. Uncertainty in local changes of effective indices is below 10-6 RIU. Local effect of acetone on coating is identified.
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