breaking time
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Author(s):  
Alexander Lopez ◽  
Solmar Varela ◽  
Ernesto Medina

Abstract The spin activity in macromolecules such as DNA and oligopeptides, in the context of the Chiral Induced Spin Selectivity (CISS) has been proposed to be due to the atomic Spin-Orbit Coupling (SOC) and the associated chiral symmetry of the structures. This coupling, associated with carbon, nitrogen, and oxygen atoms in biological molecules, albeit small (meV), can be enhanced by the geometry, and strong local polarization effects such as hydrogen bonding (HB). A novel way to manipulate the spin degree of freedom is by modifying the spectrum using a coupling to the appropriate electromagnetic radiation field. Here we use the Floquet formalism in order to show how the half-filled band Hamiltonian for DNA, can be modulated by the radiation to produce up to a tenfold increase of the effective SOC once the intrinsic coupling is present. On the other hand, the chiral model, once incorporating the orbital angular momentum of electron motion on the helix, opens a gap for different helicity states (helicity splitting) that chooses spin polarization according to transport direction and chirality, without breaking time-reversal symmetry. The observed effects are feasible in physically reasonable parameter ranges for the radiation field amplitude and frequency.


2021 ◽  
Vol 1 (1) ◽  
pp. 219-224
Author(s):  
Boni Swadesi ◽  
Ahmad Sobri ◽  
Dewi Asmorowati ◽  
Mia Feria Helmy ◽  
Ahmad Azhar ◽  
...  

Hydraulic fracturing operation is the common method to stimulate an oil well in order to make the permeability around the well become higher by injecting a mixing of fracturing fluid and proppant. Hopefully, this higher permeability can contribute to increase the production of oil and/or gas. The fundamental laboratory assessment of fracturing fluid as a part of injected component is important to be conducted before field scale implementation. One of the fundamental assessment is the static laboratory testing. In this test, the fracturing fluid sample is measured to obtain the data about its properties such as water quality, rheology, crown time and breaking time. These properties give important role to calculate the performance of the hydraulic fracturing field scale operation would be. In this research, we conducted the static laboratory testing for fracturing fluid in sensitivity of concentration which are 35, 40 and 45 systems. Every concentration have been measured its properties in order to compare each other to evaluate and select best fracturing fluid candidate for field scale application.


2021 ◽  
Author(s):  
Philippe Bourges ◽  
Dalila Bounoua ◽  
Yvan Sidis ◽  
Toshinao Loew ◽  
Bourdarot Bourdarot ◽  
...  

Abstract Despite decades of intense researches, the enigmatic pseudo-gap (PG) phase of superconducting cuprates remains an unsolved mystery. In the last 15 years, various symmetry breakings in the PG state have been discovered, spanning an intra-unit cell (IUC) magnetism, preserving the lattice translational (LT) symmetry but breaking time-reversal symmetry and parity, and an additional incipient charge density wave breaking the LT symmetry upon cooling. However, none of these states can (alone) account for the partial gapping of the Fermi surface. Here we report a hidden LT-breaking magnetism which is crucial for elucidating the PG puzzle. Our polarized neutron diffraction measurements reveal magnetic correlations, in two different underdoped YBa2Cu3O6.6 single crystals, that settle at the PG onset temperature with i) a planar propagation wave vector (π, 0) ≡ (0, π), yielding a doubling or quadrupling of the magnetic unit cell and ii) magnetic moments mainly pointing perpendicular to the CuO2 layers. The LT-breaking magnetism is at short range suggesting the formation of clusters of 5-6 unit cells that, together with the previously reported IUC magnetism, yields a hidden magnetic texture of the CuO2 unit cells hosting loop currents.


2021 ◽  
Vol ahead-of-print (ahead-of-print) ◽  
Author(s):  
Veronica Johansson ◽  
Jörgen Stenlund

PurposeRepresentations of time are commonly used to construct narratives in visualisations of data. However, since time is a value-laden concept, and no representation can provide a full, objective account of “temporal reality”, they are also biased and political: reproducing and reinforcing certain views and values at the expense of alternative ones. This conceptual paper aims to explore expressions of temporal bias and politics in data visualisation, along with possibly mitigating user approaches and design strategies.Design/methodology/approachThis study presents a theoretical framework rooted in a sociotechnical view of representations as biased and political, combined with perspectives from critical literacy, radical literacy and critical design. The framework provides a basis for discussion of various types and effects of temporal bias in visualisation. Empirical examples from previous research and public resources illustrate the arguments.FindingsFour types of political effects of temporal bias in visualisations are presented, expressed as limitation of view, disregard of variation, oppression of social groups and misrepresentation of topic and suggest that appropriate critical and radical literacy approaches require users and designers to critique, contextualise, counter and cross beyond expressions of the same. Supporting critical design strategies involve the inclusion of multiple datasets and representations; broad access to flexible tools; and inclusive participation of marginalised groups.Originality/valueThe paper draws attention to a vital, yet little researched problem of temporal representation in visualisations of data. It offers a pioneering bridging of critical literacy, radical literacy and critical design and emphasises mutual rather than contradictory interests of the empirical sciences and humanities.


2021 ◽  
pp. 654-662
Author(s):  
Zhenhua Xie ◽  
Yang Wang ◽  
Kefeng Yuan ◽  
Liang Du

2021 ◽  
Author(s):  
Kousik Bhattacharya ◽  
Sujit Kumar De

Abstract This article deals with a cost minimization objective function of an economic production quantity (EPQ) inventory model with production breakdown and deterioration. The process reliability and the environmental pollution due to over production have also been considered. The model has been split into two different scenarios according to the breaking time before and after the production period. In scenario 1, no machinery failure occurs during production run time and that of scenario 2 the failure occurs during production run time. We develop a deterministic cost minimization problem first then we fuzzify the model by considering the production rate, the demand rate and all the cost components as lock fuzzy numbers. We convert the fuzzy model into equivalent game problem by considering Gaussian normal strategic probabilities. The model has been solved with the help of different key vectors employed by the decision maker. We have shown that the value of the game might be changed with the change of different key vectors. A comparative study has been made with the numerical results of the general fuzzy and crisp models. Finally, graphical illustrations and sensitivity analysis have been done followed by a conclusion.


2021 ◽  
Vol 2 (2) ◽  
pp. p64
Author(s):  
Ren Guangling

Seabuckthorn seed oil was extracted by fat extraction method. The effects of quality of seabuckthorn seed, breaking time, soaking time and extraction solvent on the extraction rate were investigated by single factor experiment and response surface methodology. The fatty acids in seabuckthorn seed oil were determined. The research results show that the most suitable extraction conditions for using a fat extraction instrument are: seabuckthorn seed mass is 1.40 g, crushing time is 11 s, soaking time is 26 min, extraction time is 4 h, temperature is 70?, and the extraction solvent is petroleum ether. The extraction rate can reach 6.56%; the extracted seabuckthorn seed oil mainly contains three main fatty acids: linoleic acid, linolenic acid and oleic acid, these three fatty acids are also the main sn-2 fatty acids.


2021 ◽  
Vol 12 (1) ◽  
Author(s):  
P. K. Biswas ◽  
S. K. Ghosh ◽  
J. Z. Zhao ◽  
D. A. Mayoh ◽  
N. D. Zhigadlo ◽  
...  

AbstractChiral superconductors are novel topological materials with finite angular momentum Cooper pairs circulating around a unique chiral axis, thereby spontaneously breaking time-reversal symmetry. They are rather scarce and usually feature triplet pairing: a canonical example is the chiral p-wave state realized in the A-phase of superfluid He3. Chiral triplet superconductors are, however, topologically fragile with the corresponding gapless boundary modes only weakly protected against symmetry-preserving perturbations in contrast to their singlet counterparts. Using muon spin relaxation measurements, here we report that the weakly correlated pnictide compound LaPt3P has the two key features of a chiral superconductor: spontaneous magnetic fields inside the superconducting state indicating broken time-reversal symmetry and low temperature linear behaviour in the superfluid density indicating line nodes in the order parameter. Using symmetry analysis, first principles band structure calculation and mean-field theory, we unambiguously establish that the superconducting ground state of LaPt3P is a chiral d-wave singlet.


2021 ◽  
Vol 108 (Supplement_3) ◽  
Author(s):  
S García Cabeza ◽  
M Lara Guerrero ◽  
F Salinas Ramila ◽  
G J Martínez Magide ◽  
S Carnero López ◽  
...  

Abstract INTRODUCTION The present study compares ultimate tensile strength, gap strength (2, 4, 6 mm), distortion time and breaking time in a new flexor tendon suture, to a conventional technique. MATERIAL AND METHODS The flexor digitorum profundus tendons of 40 porcine forelimbs were repaired. The biomechanical analysis was carried out in a universal testing machine applying a constant speed. Tenotomy gap, the force applied and the rupture point were analysed. RESULTS The ultimate tensile strength, and 4 and 6 mm gap strength were significantly higher with the new technique compared with the conventional 4-strand cruciate technique. CONCLUSIONS The new technique is a higher provider of repair strength during early active mobilization when compared with the conventional 4-strand cruciate technique. These findings suggest that this new suture can be considered a biomechanically favourable technique for the repair of flexor tendon lacerations.


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