826 research outputs found
Variational optimization of tensor-network states with the honeycomb-lattice corner transfer matrix
We develop a method of variational optimization of the infinite projected
entangled pair states on the honeycomb lattice. The method is based on the
automatic differentiation of the honeycomb lattice corner transfer matrix
renormalization group. We apply the approach to the antiferromagnetic
Heisenberg spin-1/2 model on the honeycomb lattice. The developed formalism
gives quantitatively accurate results for the main physical observables and has
a necessary potential for further extensions
Usage of polymeric fuel tanks in the automotive industry
© Published under licence by IOP Publishing Ltd. The paper investigates usage of polymeric fuel tanks in the automotive industry
Clinical-anatomical grounding for pancreatoduodenectomy with preservation of the lesser pancreas
The article presents clinical-anatomical grounding and the first clinical experience of pancreatoduodenectomy with preservation of the lesser pancreas. Implementation of this technique is feasible due to relative anatomical and functional isolation of the lesser pancreas. For the first time in Russia, in the Clinic of Hospital Surgery of Siberian State Medical University pancreatoduodenectomy surgery with preservation of the lesser pancreas was successfully performed in female patient with cancer of the head of pancreas. Pancreatoduodenectomy with preservation of the lesser pancreas enables to augment surgical radicality and to achieve endocrine function of the pancreas at the level requiring relatively low doses of insulin therapy if any. This approach increases the length of life in this category of patients and preserves the quality of life
Pyroelectric and electrocaloric effects in PMN-based relaxors
The work was supported by the Russian Foundation of Basic Research under grant 18-02-00394
Study of Silicon Photomultiplier External Cross-Talk
Optical cross-talk is a critical characteristic of Silicon Photomultipliers
(SiPMs) and represents a significant source of the excess noise factor,
exerting a substantial influence on detector performance. During the avalanche
process of SiPMs, photons generated can give rise to both internal cross-talk
within the same SiPM and external cross-talk when photons escape from one SiPM
and trigger avalanches in others. In scenarios where SiPMs are arranged in a
compact configuration and positioned facing each other, the external cross-talk
could even dominate the cross-talk phenomenon. This paper investigates two
distinct methods for measuring external cross-talk: the counting method, which
involves operating SiPMs face-to-face and measuring their coincident signals,
and the reflection method, which employs a highly reflective film attached to
the surface of the SiPMs. External cross-talk measurements have been conducted
on several types of SiPMs, including Vacuum Ultra-Violet (VUV) sensitive SiPMs
that Fondazione Bruno Kessler (FBK) and Hamamatsu Photonics Inc (HPK) produced
for nEXO as well as visible-sensitive SiPMs provided by FBK, HPK and SensL
Technologies Ltd (SenSL) for JUNO-TAO. The results reveal a significant
presence of external cross-talk in all tested SiPMs, with HPK's SiPMs
exhibiting a dominant external cross-talk component due to the implementation
of optical trenches that effectively suppress internal cross-talk. Furthermore,
we found that the number of fired pixels resulting from internal cross-talk can
be described by combining Geometric and Borel models for all tested SiPMs,
while the external cross-talk can be predicted using a pure Borel model. These
distinct probability distributions lead to different excess noise factors,
thereby impacting the detector performance in varying ways
Hydrothermal transformations of organic matter of low permeability rocks from domanic formation of the romashkino oil field
© 2018, © 2018 Taylor & Francis Group, LLC. The oil generating potential of Domanic rocks from Dankov–Lebedyan horizon of the Zelenogorsk area of Romashkino oil field was evaluated by Rock-Eval pyrolysis technique. The result of given method depends on the content, composition, and thermal stability of organic matter in rocks. During hydrothermal processes, the distinctive conversion behavior of organic matter at temperatures of 200°С, 250°С, 300°С, and 350°С in CO2environment was revealed. The yield of obtained aquathermolysis products and their quality were evaluated. The results of the studies suggest that low-permeability carbonate rocks of the Dankov–Lebedyan horizon contain productive beds with content of Corg1.89–3.03%, which when developed using thermal methods, can become an additional source of liquid hydrocarbons
Tectonic history of the Kolyvan–Tomsk folded zone (KTFZ), Russia : insight from zircon U / Pb geochronology and Nd isotopes
The Kolyvan-Tomsk folded zone (KTFZ) represents part of the Central Asian Orogenic Belt (CAOB). The KTFZ is mainly composed of detrital Late Palaeozoic sedimentary deposits, with minor intrusions. Detrital zircon geochronology on the Upper Devonian to Lower Permian sedimentary sequences of the KTFZ and the associated Gorlovo foreland basin yields four age peaks, reflecting the magmatic events in the source terranes. These events consist of (a) a minor Neoproterozoic peak (0.9-0.7 Ga), (b) a significant Early Palaeozoic peak (550-460 Ma), with a maximum at 500 Ma, and two well-defined Late Palaeozoic peaks during (c) the Middle-Late Devonian (385-360 Ma) and (d) the Carboniferous-Early Permian (360-280 Ma), with a maximum at 320 Ma. Older zircons (>1 Ga) are quite rare in the sampled sedimentary sequences. Slightly negative epsilon Nd values and associated relatively young Nd model ages were obtained (epsilon Nd(T) = -0.78, T (DM) ~1.1 Ga for Upper Devonian sandstones, epsilon Nd(T) = -1.1, T (DM) ~1.1 Ga for Lower Permian sandstones), suggesting only minor contribution of ancient continental crust to the main sedimentary units of the KTFZ. All intrusive and volcaniclastic rocks on the contrary are characterized by high positive epsilon Nd(T) values in the range of 3.78-6.86 and a Late Precambrian model age (T (DM) = 581-916 Ma), which corroborates its juvenile nature and an important depleted mantle component in their source. The oldest unit of the KTFZ, the Bugotak volcanic complex formed at the Givetian-Early Frasnian transition, at about 380 Ma. Upper Devonian detrital deposits of the KTFZ were formed in the Early Palaeozoic accretion belt of the Siberian continent and specifically in a passive continental margin environment. Deposits of the Gorlovo foreland basin, adjoining the KTFZ, were accumulated as a result of erosion of the Carboniferous-Early Permian volcanic rocks, which are now buried under the Meso-Cenozoic sedimentary cover of the West Siberian Basin. The magmatic events, recorded in the KTFZ zircon data, correspond to the most significant magmatic stages that affected the western part of the CAOB as a whole
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