The TOTEM collaboration has measured the proton-proton total cross section at √s=8 TeV using a luminosity-independent method. In LHC fills with dedicated beam optics, the Roman pots have been ...inserted very close to the beam allowing the detection of ~90% of the nuclear elastic scattering events. Simultaneously the inelastic scattering rate has been measured by the T1 and T2 telescopes. By applying the optical theorem, the total proton-proton cross section of (101.7±2.9) mb has been determined, well in agreement with the extrapolation from lower energies. This method also allows one to derive the luminosity-independent elastic and inelastic cross sections: σ(el)=(27.1±1.4) mb; σ(inel)=(74.7±1.7) mb.
Safety in an integral sense is a comprehensive tool by which the humans ensure the level of their security and the sustainable development of them and of other basic public assets in a given ...territory. In addition to individual parts of human system it is necessary to consider their mutual links and flows being among them. One of the sectors in which security plays an important role is tourism. An integral part of it is transportation of persons, but also material and its associated safety. Safety is fundamental to any transport system; it must always be the top priority. The authors of this article focused on one particular specific area: the safety of transporting dangerous goods in the Czech Republic. The main reason was that traffic accidents with dangerous goods have big impacts on goods and vicinity, i.e. humans and environment (Maturo in Ecol Indic 90:305–315,
2018
). They are accompanied by fire, explosion, leakage of dangerous substances, or combination of these phenomena. These facts have economic impacts on carriers (damage or destruction of goods) and as well as on protected assets at the accident site (damage to infrastructure, human health injury or loss of human lives of persons being in the vicinity, harms in environment). The aim of the paper is to analyse the traffic accidents involving dangerous substances on the motorways and main railway routes in the Czech Republic, to characterize their impacts, to judge response in case of accidents´ occurrences and on evaluation of real data to suggest the measures for increasing safety in the carriage of dangerous substances. The authors focused on the statistical evaluation of accidents and on analysis of accidents during the transport of dangerous substances from the perspective of the impacts on people and other public assets.
Abstract
The TOTEM collaboration at the CERN LHC has measured the differential cross-section of elastic proton–proton scattering at
$$\sqrt{s} = 8\,\mathrm{TeV}$$
s
=
8
TeV
in the squared ...four-momentum transfer range
$$0.2\,\mathrm{GeV^{2}}< |t| < 1.9\,\mathrm{GeV^{2}}$$
0.2
GeV
2
<
|
t
|
<
1.9
GeV
2
. This interval includes the structure with a diffractive minimum (“dip”) and a secondary maximum (“bump”) that has also been observed at all other LHC energies, where measurements were made. A detailed characterisation of this structure for
$$\sqrt{s} = 8\,\mathrm{TeV}$$
s
=
8
TeV
yields the positions,
$$|t|_{\mathrm{dip}} = (0.521 \pm 0.007)\,\mathrm{GeV^2}$$
|
t
|
dip
=
(
0.521
±
0.007
)
GeV
2
and
$$|t|_{\mathrm{bump}} = (0.695 \pm 0.026)\,\mathrm{GeV^2}$$
|
t
|
bump
=
(
0.695
±
0.026
)
GeV
2
, as well as the cross-section values,
$$\left. {\mathrm{d}\sigma /\mathrm{d}t}\right| _{\mathrm{dip}} = (15.1 \pm 2.5)\,\mathrm{{\mu b/GeV^2}}$$
d
σ
/
d
t
dip
=
(
15.1
±
2.5
)
μ
b
/
GeV
2
and
$$\left. {\mathrm{d}\sigma /\mathrm{d}t}\right| _{\mathrm{bump}} = (29.7 \pm 1.8)\,\mathrm{{\mu b/GeV^2}}$$
d
σ
/
d
t
bump
=
(
29.7
±
1.8
)
μ
b
/
GeV
2
, for the dip and the bump, respectively.
Celotno besedilo
Dostopno za:
DOBA, IZUM, KILJ, NUK, PILJ, PNG, SAZU, SIK, UILJ, UKNU, UL, UM, UPUK
When used in construction, the properties of wood-based materials they are mainly affected by moisture. Moisture sorption and the associated swelling has an impact on the resistance of materials to ...biocidal attacks, on their mechanical properties or air permeability, and on comfort of use and durability of the structure. Equilibrium moisture content (EMC) and thickness swelling (TS) depending on the relative humidity for plywood (PW), particleboard (PB) and oriented strand board (OSB), for load-bearing purposes in humid environments and bonded with melamine-urea-formaldehyde resin (MUF), are studied in detail in this paper. Equilibrium moisture content and thickness swelling are influenced by the type of material, density, quantity of adhesive composition, and paraffin. The highest values of equilibrium moisture content were found in plywood, whilst the highest thickness swelling was achieved by OSB. A high dependency of nonrecoverable thickness swelling on the equilibrium moisture of the material was also ascertained. The proportion of nonrecoverable thickness swelling increases exponentially, in particular if the material's equilibrium moisture content exceeds 12%.
Low capacity of river banks is a problem of many world cities. Extension can be realised in many ways. One of the ways is to use a system of floating piers. Usual types of piers are filled with ...floating material, which supports the pier for the whole lifetime. The system of piers described in this article is innovative, because it is supported by an air bag, which can be deflated and then the whole system sinks down to the bottom of the river. This can be helpful in case of danger of floods, because there will be no need to transport the piers to a secure dock. Piers are designed for easy modular connection in various groups. The main types of groups are linear and areal. This article briefly describes the design of fibre reinforced concrete pier and other support constructions which are necessary for the right function of the system. The design of the pier was verified by hydraulic experiments on models in scale 1:10 to real pier. The article contains the description and results of the experiments that have proven the system to be feasible.
The proton–proton elastic differential cross section
d
σ
/
d
t
has been measured by the TOTEM experiment at
s
=
2.76
TeV
energy with
β
∗
=
11
m
beam optics. The Roman Pots were inserted to 13 times ...the transverse beam size from the beam, which allowed to measure the differential cross-section of elastic scattering in a range of the squared four-momentum transfer (|
t
|) from 0.36 to
0.74
GeV
2
. The differential cross-section can be described with an exponential in the |
t
|-range between 0.36 and
0.54
GeV
2
, followed by a diffractive minimum (dip) at
|
t
dip
|
=
(
0.61
±
0.03
)
GeV
2
and a subsequent maximum (bump). The ratio of the
d
σ
/
d
t
at the bump and at the dip is
1.7
±
0.2
. When compared to the proton–antiproton measurement of the D0 experiment at
s
=
1.96
TeV
, a significant difference can be observed. Under the condition that the effects due to the energy difference between TOTEM and D0 can be neglected, the result provides evidence for the exchange of a colourless C-odd three-gluon compound state in the
t
-channel of the proton–proton and proton–antiproton elastic scattering.
Celotno besedilo
Dostopno za:
DOBA, IZUM, KILJ, NUK, PILJ, PNG, SAZU, SIK, UILJ, UKNU, UL, UM, UPUK
The paper reports on the behaviour of low alloyed TRIP (transformation induced plasticity) steel with Niobium during tensile test. The structures were analysed using in-situ tensile testing coupled ...with electron backscattering diffraction (EBSD) analysis carried out in scanning electron microscope (SEM). Steel specimens were of same chemical composition; however three different annealing temperatures, 800 °C, 850 °C and 950 °C, were applied to the material during the heat treatment. The treatment consisted of annealing for 20 minutes in the furnace; cooling in salt bath after the heating and holding at 425 °C for 20 minutes for all the samples. Untreated bar was used as reference material. Flat samples for deformation stage were cut out of the heat-treated bars. In situ documentation of microstructure and crystallography development were carried out during the deformation experiments. High deformation lead to significant degradation of EBSD signal.
Norway spruce (Picea abies L. Karst.) provenances from Central Europe (Hercynian-Sudetes area) were evaluated in a long-term experimental project (Germany-Czech Republic) 36 years after the ...outplanting. The growth characteristics, mortality and qualitative morphological characteristics of 64 spruce provenances were evaluated on the experimental plot Ledeč-Zaháj, in the Czech-Moravian Highland region of the Czech Republic, in typical conditions for Norway spruce cultivation. Results show 15-20% differences in height and radial growth between provenances and insignificant differences in qualitative characteristics e.g. stem shape, branch density and shape and also health state. Environmental variables that significantly influenced production characteristics include longitude, latitude and altitude of the original locations of the provenances, while average annual temperature and average annual precipitation were not significant. Given conditions of the experimental plot, optimal production occurred with those provenances originally from 49-51 N latitude and 13-20 E longitude.
Based on our generic concept for the design of superhard (HVickers > or = 40 GPa) nanocomposites with a high thermal stability and oxidation resistance we discuss the role of nitrogen pressure and ...substrate temperature during the deposition and the detrimental effect of impurities on the formation of superhard nanocomposites with a high thermal stability. It is shown that inappropriate choice of the deposition parameters or impurities in the coatings are the possible reason of the poor reproducibility of our results by some authors. In order to differentiate between the superhard nanocomposites in which the superhardness originates from a stable nanostructure and ordinary coatings in which the hardness enhancement is due to energetic ion bombardment during their deposition we discuss the different behavior of such coatings and nc-TiN/a-Si3N4 superhard nanocomposites upon annealing. It is further shown that hydrogen and oxygen impurities degrade the hardnes the oxygen content in the coatings amounts to about 0.5 at.% or more, the hardness remains limited to 35 GPa or less.
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