3,799 research outputs found
Formation of nanocrystalline aluminum magnesium alloys by mechanical alloying
The effect of the nominal Mg content and the milling time on the microstructure and the
hardness of mechanically alloyed Al (Mg) solid solutions is studied. The crystallite size
distribution and the dislocation structure are determined by X-ray diffraction peak
profile analysis and the hardness is obtained from depth sensing indentation test.
Magnesium gradually goes into solid solution during ball milling and after about 3 h
almost complete solid solution state is attained up to the nominal Mg content of the
alloys. With increasing milling time the dislocation density, the hardness and the Mg
content in solid solution are increasing, whereas the crystallite size is decreasing. A
similar tendency of these parameters is observed at a particular duration of ball milling
with increasing of the nominal Mg content. At the same time for long milling period the
dislocation density slightly decreases together with a slight reduction of the hardness
In vitro starch binding experiments: Study of the proteins related to grain hardness of wheat
Two friabilin components, puroindoline a and GSP-1 were expressed in Escherichia coli. Starch
binding properties of the recombinant polypeptides and of friabilin extracted from wheat flour were
compared in vitro. The produced proteins as well as native wheat friabilin bound to starch granules
prepared from different (soft, hard and durum) wheat cultivars. Starch granules also bound
specifically several wheat endosperm proteins other than friabilin
Testing the Structure of Multipartite Entanglement with Bell Inequalities
We show that the rich structure of multipartite entanglement can be tested
following a device-independent approach. Specifically we present Bell
inequalities for distinguishing between different types of multipartite
entanglement, without placing any assumptions on the measurement devices used
in the protocol, in contrast with usual entanglement witnesses. We first
address the case of three qubits and present Bell inequalities that can be
violated by W states but not by GHZ states, and vice versa. Next, we devise
'sub-correlation Bell inequalities' for any number of parties, which can
provably not be violated by a broad class of multipartite entangled states
(generalizations of GHZ states), but for which violations can be obtained for W
states. Our results give insight into the nonlocality of W states. The
simplicity and robustness of our tests make them appealing for experiments.Comment: 7 page
Post-selected weak measurement beyond the weak value
Closed expressions are derived for the quantum measurement statistics of
pre-and postselected gaussian particle beams. The weakness of the pre-selection
step is shown to compete with the non-orthogonality of post-selection in a
transparent way. The approach is shown to be useful in analyzing
post-selection-based signal amplification, allowing measurements to be extended
far beyond the range of validity of the well-known Aharonov-Albert-Vaidman
limit.Comment: The published version; with respect to previous one, note changes in
Eqs. (16),(17),(19)
Effects of the disk tillage on soil condition, crop yield and weed infestation
This research was instigated by the fact that during the last decade annually repeated shallow disk tillage on the same field became frequent practice in Hungary. In order to study the changes of soil condition associated with disk tillage and to assess it is consequences, long-term tillage field experiments with different levels of nutrients were set up in 1991 (A) and in 1994 (B) on Chromic Luvisol at Gödöllö. The effects of disk tillage (D) and disk tillage combined with loosening (LD) on soil condition, on yield of maize and winter wheat, and on weed infestation were examined. The evaluation of soil condition measured by cone index and bulk density indicated that use of disking annually resulted in a dense soil layer below the disking depth (diskpan-compaction). It was found, that soil condition deteriorated by diskpan-compaction decreased the yield of maize significantly by 20 and 42% (w/w), and that of wheat by 13 and 15% (w/w) when compared to soils with no diskpan-compaction. Averaged over seven years, and three fertilizer levels, the cover % of the total, grass and perennial weeds on loosened soils were 73, 69 and 65% of soils contained diskpan-compaction
Shock waves on complex networks
Power grids, road maps, and river streams are examples of infrastructural
networks which are highly vulnerable to external perturbations. An abrupt local
change of load (voltage, traffic density, or water level) might propagate in a
cascading way and affect a significant fraction of the network. Almost
discontinuous perturbations can be modeled by shock waves which can eventually
interfere constructively and endanger the normal functionality of the
infrastructure. We study their dynamics by solving the Burgers equation under
random perturbations on several real and artificial directed graphs. Even for
graphs with a narrow distribution of node properties (e.g., degree or
betweenness), a steady state is reached exhibiting a heterogeneous load
distribution, having a difference of one order of magnitude between the highest
and average loads. Unexpectedly we find for the European power grid and for
finite Watts-Strogatz networks a broad pronounced bimodal distribution for the
loads. To identify the most vulnerable nodes, we introduce the concept of
node-basin size, a purely topological property which we show to be strongly
correlated to the average load of a node
Multisetting Bell-type inequalities for detecting genuine tripartite entanglement
In a recent paper, Bancal et al. put forward the concept of
device-independent witnesses of genuine multipartite entanglement. These
witnesses are capable of verifying genuine multipartite entanglement produced
in a lab without resorting to any knowledge of the dimension of the state space
or of the specific form of the measurement operators. As a by-product they
found a three-party three-setting Bell inequality which enables to detect
genuine tripartite entanglement in a noisy 3-qubit Greenberger-Horne-Zeilinger
(GHZ) state for visibilities as low as 2/3 in a device-independent way. In this
paper, we generalize this inequality to an arbitrary number of settings,
demonstrating a threshold visibility of 2/pi~0.6366 for number of settings
going to infinity. We also present a pseudo-telepathy Bell inequality achieving
the same threshold value. We argue that our device-independent witnesses are
optimal in the sense that the above value cannot be beaten with
three-party-correlation Bell inequalities.Comment: 7 page
Unjamming of Granular Packings due to Local Perturbations: Stability and Decay of Displacements
We study the mechanical response generated by local deformations in jammed
packings of rigid disks. Based on discrete element simulations we determine the
critical force of the local perturbation that is needed to break the mechanical
equilibrium and examine the generated displacement field. Displacements decay
as a power law of the distance from the perturbation point. The decay exponent
and the critical force exhibit nontrivial dependence on the friction: Both
quantities are nonmonotonic and have a sharp maximum at the friction
coefficient 0.1. We find that the mechanical response properties are closely
related to the problem of force-indeterminacy where similar nonmonotonic
behavior was observed previously. We establish direct connection between the
critical force and the ensemble of static force networks.Comment: 4 pages, 4 figure
Megszabva. Városi kormányzás másutt és itthon
A helyi önkormányzatokat szokásos megközelĂtĂ©s szerint az állami terĂĽletbeosztáshoz kötik. A feladatok ellátása ugyanakkor a városiasság kĂĽlönbözĹ‘ fokait feltĂ©telezi, tekintet nĂ©lkĂĽl adott telepĂĽlĂ©s Ă©s környezete közigazgatási besorolásának milyensĂ©gĂ©re. Az állami terĂĽletbeosztáshoz nem kötött városi kormányzás kötetlen formái mindig is „körbelengik” a merevebb hivatalszervezĂ©si struktĂşrákat. A jelensĂ©g ebben az Ă©rtelemben manapság reneszánszát Ă©li EurĂłpában Ă©s a fejlett világ többi rĂ©szĂ©n. A hálĂłzatos formák tapinthatĂłak az urbanizált helyek között Ă©s közössĂ©geikben, de ezek mindig egyĂĽtt Ă©lnek merevebb struktĂşrákkal is. Ilyen a hierarchikus állami szerepek Ă©rvĂ©nyesĂĽlĂ©se, ami egyben veszĂ©lyeket hordoz a hálĂłzatosságra. De mind az államigazgatás szokásos struktĂşrája, mind a hálĂłzati rendszer potenciálisan kikezdi magát a helyi demokráciát is. A problĂ©ma feltárása Ă©rdekĂ©ben a tanulmány analitikus Ă©s empirikus mĂłdszert alkalmaz, az utĂłbbit összehasonlĂtĂł kĂ©rdĹ‘Ăves felmĂ©rĂ©sek adatainak elemzĂ©se Ăştján
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