235 research outputs found
Organocatalytic Fluorogenic Synthesis of Chromenes
Two fluorescent derivatives of 2-amino-3-carbonitrile-4H-chromene were synthesized by means of a fluorogenic Michael addition of dimedone to dicyano alkene labeled BODIPY derivatives. Different organocatalysts were used in different conditions to obtain compounds 3 and 4 in good yield (up to 65% and 85 and moderate enantiomeric excess (51% and 41% ee, respectively). This work provides the first example of an enantioselective organocatalytic conversion combined with fluorogenesis
Quantum reading of quantum information
We extend the notion of quantum reading to the case where the information to be retrieved, which is encoded into a set of quantum channels, is of quantum nature. We use two-qubit unitaries describing the system-environment interaction, with the initial environment state determining the system's input-output channel and hence the encoded information. The performance of the most relevant two-qubit unitaries is determined with two different approaches: (i) one-shot quantum capacity of the channel arising between environment and system's output; (ii) estimation of parameters characterizing the initial quantum state of the environment. The obtained results are mostly in (qualitative) agreement, with some distinguishing features that include the CNOT unitary
Union bound for quantum information processing
In this paper, we prove a quantum union bound that is relevant when
performing a sequence of binary-outcome quantum measurements on a quantum
state. The quantum union bound proved here involves a tunable parameter that
can be optimized, and this tunable parameter plays a similar role to a
parameter involved in the Hayashi-Nagaoka inequality [IEEE Trans. Inf. Theory,
49(7):1753 (2003)], used often in quantum information theory when analyzing the
error probability of a square-root measurement. An advantage of the proof
delivered here is that it is elementary, relying only on basic properties of
projectors, the Pythagorean theorem, and the Cauchy--Schwarz inequality. As a
non-trivial application of our quantum union bound, we prove that a sequential
decoding strategy for classical communication over a quantum channel achieves a
lower bound on the channel's second-order coding rate. This demonstrates the
advantage of our quantum union bound in the non-asymptotic regime, in which a
communication channel is called a finite number of times. We expect that the
bound will find a range of applications in quantum communication theory,
quantum algorithms, and quantum complexity theory.Comment: v2: 23 pages, includes proof, based on arXiv:1208.1400 and
arXiv:1510.04682, for a lower bound on the second-order asymptotics of
hypothesis testing for i.i.d. quantum states acting on a separable Hilbert
spac
Effect of packing density on thermal properties of granular activated carbon packed bed by using of inverse heat conduction method
Paper presented to the 10th International Conference on Heat Transfer, Fluid Mechanics and Thermodynamics, Florida, 14-16 July 2014.The ability of granular activated carbon (GAC) to adsorb large mass of refrigerant gases makes it ideal for use in thermal compressor. In order to make thermal compressor economically viable, the size must be reduced and for that reason thermal responses should be increase as much as possible during heating and cooling process. This paper investigates the effect of GAC bed density on the thermal transient responses when a sudden change in temperature is imposed on wall of a test sample reactor. The test sample consists of 1” OD stainless steel with 0.71 [mm]thickness and 200[mm]length that is loaded with compacted granular activated. The granular carbon used is 208C (coconut shell base) with 13×30 mesh size and provided by ‘Chemviron Carbon Company’. To find the heat transfer coefficient of the contact wall/packed carbon (h) and packed bed thermal conductivity (k) a numerical inverse heat conduction method is used in conjunction with an iterative process based on minimizing the Mean Square Error (MSE) from measured temperatures. Experimental work is carried out by measuring the wall and centre temperatures of submerged sample in a temperature controlled water bath at around 85[oC]. Five samples with the packed bed density ranging from 500 [kg/m3] to 800 [kg/m3] were tested and the results show a quasi-linear increase of both thermal conductivity (k) and heat transfer coefficient of the contact wall/packed carbon (h) with the packed bed density: 0.15 [W/m.K]< k < 0.45[W/m.K]and 150 [W/m2.K]< h < 1400 [W/m2.K].dc201
Optimal input states for quantifying the performance of continuous-variable unidirectional and bidirectional teleportation
Continuous-variable (CV) teleportation is a foundational protocol in quantum
information science. A number of experiments have been designed to simulate
ideal teleportation under realistic conditions. In this paper, we detail an
analytical approach for determining optimal input states for quantifying the
performance of CV unidirectional and bidirectional teleportation. The metric
that we consider for quantifying performance is the energy-constrained channel
fidelity between ideal teleportation and its experimental implementation, and
along with this, our focus is on determining optimal input states for
distinguishing the ideal process from the experimental one. We prove that,
under certain energy constraints, the optimal input state in unidirectional, as
well as bidirectional, teleportation is a finite entangled superposition of
twin-Fock states saturating the energy constraint. Moreover, we also prove
that, under the same constraints, the optimal states are unique; that is, there
is no other optimal finite entangled superposition of twin-Fock states.Comment: 26 pages, 4 figures, accepted for publication in Physical Review
Molecular Identification and Differentiation of Fasciola Isolates Using PCR- RFLP Method Based on Internal Transcribed Spacer (ITS1, 5.8S rDNA, ITS2)
Background: In this study, we used both ITS1 and ITS2 for molecular identification of Fasciola species.Methods: The region between 18S and 28S of ribosomal DNA was used in PCR-RFLP method for molecular identification of Fasciola species. Ninety trematodes of Fasciola were collected during abattoir inspection from livers of naturally infected sheep and cattle from Khorasan, East Azerbaijan, and Fars provinces in Iran. After DNA extraction, PCR was performed to amplify region ITS1, 5.8S rDNA, ITS2. To select a suitable restriction enzyme, we sequenced and ana-lyzed the PCR products of F. hepatica and F. gigantica samples from sheep and cattle. Tsp509I fast digest restriction enzyme was selected for RFLP method that caused the separation specifi-cally of Fasciola species. Results: The fragment approximately 1000bp in all of the Fasciola samples was amplified and then digested with the Tsp509I restriction endonuclease. Seventy F. hepatica and 20 F. gigantica were identified of total 90 Fasciola isolates.Conclusion: The new PCR-RFLP assay using Tsp509I restriction enzyme provides a simple, practical, fast, low cost, and reliable method for identification and differentiation of Fasciola isolates
Two Inputs Five-Level Quasi-Z-Source Inverter
This paper combines quasi-Z-source into a typical five-level inverter, which includes two dc voltage sources, two quasi-Z-sources and five switching devices. In this structure, the output voltage amplitude is not limited to dc voltage source and it can be increased by quasi-Z-source. Besides, due to nature of Z-source families, this new structure is reliable and higher efficiency. Also, in this inverter, two quasi-Z-networks can be controlled independently. This paper also proposes new switching algorithms for proposed five-level dual quasi-Z-Source inverter based on pulse width modulation (PWM) and selective harmonic elimination method (SHEM) algorithms .The performance of proposed inverter and switching algorithm are validated with simulation results using MATLAB/SIMULINK software and experimental results based PCI-1716 data acquisition system
Inaktivacija bakterije Listeria monocytogenes u podlozi s agarom i goveđim mesom pomoću UVC zraka
The aim of this study is to evaluate the eff ect of meat content and surface smoothness on the deactivation of Listeria monocytogenes in beef-agar food models achieved by shortwave ultraviolet (UVC) light. Food models with various meat contents were made using chopped beef slices and agar solution. Prepared models together with a Listeria selective agar (LSA) plate and a slice of cooked beef were inoculated with L. monocytogenes and then exposed to UVC light. Population of Listeria reduced to below the level of detection on the LSA plates. As the content of beef in the beef-agar models increased, more L. monocytogenes cells survived. Survival was greatest on the treated cooked slice of beef. To bett er understand the effect of surface irregularities, a white light interferometer was used to analyse the surface smoothness of beef-agar media and LSA plates. No correlation was observed between the surface roughness of seven out of nine types of produced beef-agar media and the degree of inactivation resulting from UVC radiation at the given dose, whereas, less bacterial cells were killed as beef content of the food models increased. The findings of the current study show that the chemical composition of the treated sample also plays an important role in pathogen resistance and survival, meaning that two samples with similar surface irregularities but diff erent chemical composition might produce very diff erent inactivation results when exposed to UVC light.Svrha je ovoga rada bila ispitati učinak sastava (udjela mesa) i teksture podloge s agarom i goveđim mesom na inaktivaciju bakterije Listeria monocytogenes pomoću kratkovalnog ultraljubičastog (UVC) zračenja. Podloge su pripremljene s različitim udjelima komadića mesa te s otopinom agara. Podloge s goveđim mesom, selektivne podloge za izolaciju bakterije Listeria monocytogenes (engl. Listeria selective agar, LSA) i kuhani goveđi odresci inokulirani su bakterijom L. monocytogenes i zatim izloženi UVC zračenju. Populacija se L. monocytogenes na LSA podlozi nakon zračenja smanjila ispod granice detekcije. U podlogama s većim udjelom mesa preživio je i veći broj bakterija. Najviše je bakterija preživjelo na kuhanom goveđem odresku. Za bolje shvaćanje utjecaja površinskih nepravilnosti na inaktivaciju bakterija interferometrom su analizirane podloge s goveđim mesom i LSA podloga. U sedam od devet uzoraka nije utvrđena nikakva korelacija između površinskih neravnina i stupnja inaktivacije bakterije UVC zračenjem. U podlogama s većim udjelom mesa inaktivirano je manje stanica bakterija. Rezultati ovog istraživanja pokazuju da kemijski sastav uzorka ima bitnu ulogu u rezistenciji i preživljavanju patogena, što znači da na površinama sličnih tekstura ali različitog kemijskog sastava inaktivacija UVC zračenjem može imati sasvim različit učinak
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