100 research outputs found
Coherence loss and revivals in atomic interferometry: A quantum-recoil analysis
The coherence effects induced by external photons coupled to matter waves
inside a Mach-Zehnder three-grating interferometer are analyzed. Alternatively
to atom-photon entanglement scenarios, the model considered here only relies on
the atomic wave function and the momentum shift induced in it by the photon
scattering events. A functional dependence is thus found between the
observables, namely the fringe visibility and the phase shift, and the
transversal momentum transfer distribution. A good quantitative agreement is
found when comparing the results obtained from our model with the experimental
data.Comment: 18 pages, 4 figure
On Wheeler's delayed-choice Gedankenexperiment and its laboratory realization
Here, we present an analysis and interpretation of the experiment performed
by Jacques et al. (2007 Science 315, 966), which represents a realization of
Wheeler's delayed-choice Gedankenexperiment. Our analysis is based on the
evolution of the photon state, since the photon enters into the Mach-Zehnder
interferometer with a removable beam-splitter until it exits. Given the same
incident photon state onto the output beam-splitter, BS_output, the photon's
state at the exit will be very different depending on whether BS_output is on
or off. Hence, the statistics of photon counts collected by the two detectors,
positioned along orthogonal directions at the exit of the interferometer, is
also going to be very different in either case. Therefore, it is not that the
choice of inserting (on) or removing (off) a beam-splitter leads to a delayed
influence on the photon behavior before arriving at the beam-splitter, but that
such a choice influences the photon state at and after BS_output, i.e., after
it has exited from the Mach-Zehnder interferometer. The random on/off choice at
BS_output has no delayed effect on the photon to behave as a wave or a
corpuscle at the entrance and inside the interferometer, but influences the
subsequent evolution of the photon state incident onto BS_output.Comment: 7 pages, 4 figure
Supplementary data for article: LonÄar, N.; SlaviÄ, M. Å .; VujÄiÄ, Z.; BožiÄ, N. Mixed-Mode Resins: Taking Shortcut in Downstream Processing of Raw-Starch Digesting Ī±-Amylases. Scientific Reports 2015, 5. https://doi.org/10.1038/srep15772
Supplementary material for: [https://doi.org/10.1038/srep15772]Related to published version: [http://cherry.chem.bg.ac.rs/handle/123456789/1985
Mixed-mode resins: taking shortcut in downstream processing of raw-starch digesting alpha-amylases
Bacillus licheniformis 9945a alpha-amylase is known as a potent enzyme for raw starch hydrolysis. In this paper, a mixed mode Nuvia cPrime (TM) resin is examined with the aim to improve the downstream processing of raw starch digesting amylases and exploit the hydrophobic patches on their surface. This resin combines hydrophobic interactions with cation exchange groups and as such the presence of salt facilitates hydrophobic interactions while the ion-exchange groups enable proper selectivity. alpha-Amylase was produced using an optimized fed-batch approach in a defined media and significant overexpression of 1.2 g L-1 was achieved. This single step procedure enables simultaneous concentration, pigment removal as well as purification of amylase with yields of 96% directly from the fermentation broth.Supplementary material: [http://cherry.chem.bg.ac.rs/handle/123456789/3384
On the influence of resonance photon scattering on atom interference
Here, the influence of resonance photon-atom scattering on the atom
interference pattern at the exit of a three-grating Mach-Zehnder interferometer
is studied. It is assumed that the scattering process does not destroy the
atomic wave function describing the state of the atom before the scattering
process takes place, but only induces a certain shift and change of its phase.
We find that the visibility of the interference strongly depends on the
statistical distribution of transferred momenta to the atom during the
photon-atom scattering event. This also explains the experimentally observed
(Chapman et al 1995 Phys. Rev. Lett. 75 2783) dependence of the visibility on
the ratio d_p/\lambda_i = y'_{12} (2\pi/kd\lambda_i), where y'_{12} is distance
between the place where the scattering event occurs and the first grating, k is
the wave number of the atomic center-of-mass motion, is the grating
constant and \lambda_i is the photon wavelength. Furthermore, it is remarkable
that photon-atom scattering events happen experimentally within the Fresnel
region, i.e. the near field region, associated with the first grating, which
should be taken into account when drawing conclusions about the relevance of
"which-way" information for the interference visibility.Comment: 9 pages, 1 figur
Uporedna analiza izoformi Ī±-amilaze iz srednjeg creva larvi Cerambyx cerdo L. (Coleoptera: Cerambycidae) iz prirode i gajenih na veÅ”taÄkoj podlozi
alpha-Amylase isoforms of Cerambyx cerdo larvae from the wild (ML and SL) and reared in the laboratory (ADL) were compared. Three amylase isoforms were presented in the SL and ML extracts while two isoforms were presented in the ADL according to zymogram after isoelectric focusing (IEF). All C. cerdo amylase isoforms were acidic proteins (pI lt 3.5). Seven amylase isoforms (ACC 1-7) from the midgut of C. cerdo larvae were found in the ML midgut extract, six in the SL extract, and four in the ADL extract according to native PAGE zymogram. The ADL amylase had the highest activity. All crude midgut extracts of C. cerdo larvae were fractionated on a Superose 12 HR column. The molecular mass of the ACC was estimated to be 34 kDa.UporeÄene su izoforme Ī±-amilaze larvi Cerambyx cerdo sakupljenih iz prirode (ML i SL) i gajenih na veÅ”taÄkoj podlozi u laboratoriji (ADL). Zimogramskom detekcijom posle IEF-a po tri izoforme su detektovane u ML i SL ekstraktima, a u ADL dve izoforme. Sve amilazne izoforme iz C. cerdo su bile kisele (pI lt 3.5). Zimogramskom detekcijom posle nativne elektroforeze sedam izoformi je detektovano u ML ekstraktu, Å”est u SL ekstraktu i Äetiri u ADL ekstraktu. NajveÄa amilazna aktivnost je detektovana u ADL ekstraktu. Svi ekstrakti srednjih creva larvi C. cerdo su frakcionisani na koloni Superose 12 HR. Molekulska masa ACC-a je bila 34 kDa
Properties and nature of Be stars 30. Reliable physical properties of a semi-detached B9.5e+G8III binary BR CMi = HD 61273 compared to those of other well studied semi-detached emission-line binaries
Reliable determination of the basic physical properties of hot emission-line
binaries with Roche-lobe filling secondaries is important for developing the
theory of mass exchange in binaries. It is a very hard task, however, which is
complicated by the presence of circumstellar matter in these systems. So far,
only a small number of systems with accurate values of component masses, radii,
and other properties are known. Here, we report the first detailed study of a
new representative of this class of binaries, BR CMi, based on the analysis of
radial velocities and multichannel photometry from several observatories, and
compare its physical properties with those for other well-studied systems. BR
CMi is an ellipsoidal variable seen under an intermediate orbital inclination
of ~51 degrees, and it has an orbital period of 12.919059(15) d and a circular
orbit. We used the disentangled component spectra to estimate the effective
temperatures 9500(200) K and 4655(50) K by comparing them with model spectra.
They correspond to spectral types B9.5e and G8III. We also used the
disentangled spectra of both binary components as templates for the 2-D
cross-correlation to obtain accurate RVs and a reliable orbital solution. Some
evidence of a secular period increase at a rate of 1.1+/-0.5 s per year was
found. This, together with a very low mass ratio of 0.06 and a normal mass and
radius of the mass gaining component, indicates that BR CMi is in a slow phase
of the mass exchange after the mass-ratio reversal. It thus belongs to a still
poorly populated subgroup of Be stars for which the origin of Balmer emission
lines is safely explained as a consequence of mass transfer between the binary
components.Comment: 17 pages, 5 figures, accepted for publication in Astronomy and
Astrophysics. appears in Astronomy and Astrophysics 201
Supplementary data for the article: Loncar, N.; Bozic, N.; Vujcic, Z. Expression and Characterization of a Thermostable Organic Solvent-Tolerant Laccase from Bacillus Licheniformis ATCC 9945a. J. Mol. Catal. B-Enzym. 2016, 134, 390ā395. https://doi.org/10.1016/j.molcatb.2016.06.005
Supplementary material for: [https://doi.org/10.1016/j.molcatb.2016.06.005]Related to published version: [http://cherry.chem.bg.ac.rs/handle/123456789/2375]Related to accepted version: [http://cherry.chem.bg.ac.rs/handle/123456789/3517
Supplementary data for the article: LonÄar, N.; DraÅ”koviÄ, N.; BožiÄ, N.; Romero, E.; SimiÄ, S.; Opsenica, I.; VujÄiÄ, Z.; Fraaije, M. W. Expression and Characterization of a Dye-Decolorizing Peroxidase from Pseudomonas Fluorescens Pf0-1. Catalysts 2019, 9 (5). https://doi.org/10.3390/catal9050463
Supplementary material for: [https://doi.org/10.3390/catal9050463]Related to published version: [http://cherry.chem.bg.ac.rs/handle/123456789/3709
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