indeed enhanced and is increased as the system size increases in the 2D Hubbard **model**. The enhancement ratio increases almost linearly L as the system size is increased, which is an indication of the existence of **superconductivity**. Our criterion is that when the en- hancement ratio as a function of the system size L is proportional to a certain power of L , **superconductivity** will be developed. This ratio depends on U and is reduced as U is decreased. The dependence on the band filling shows a dome structure as a function of the electron density. In the 10 10 system, the ratio is greater than 1 in the **range** 0.3 n e 0.9 . Let us also mention on **superconductivity** at half-filling. Our results indicates the absence of **superconductivity** in the half-filling case because there is no enhancement of pair correlation functions

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In addition to this two-step strategy, we propose a sampling method for selecting the initial random state. It is well known that the random vector method is quite effective for the trace calculation of the partition function. If the Hamiltonian has some symmetry, the basis states are divided into symmetry sectors. In each symmetry sec- tor we calculate the partition function. At the infinitely **high** T a sampling weight of each symmetry sector is proportional to the number of basis states in the symmetry sector. But at very low T , the partition function de- pends extremely on the lowest energy E s of the symmetry sector s . Based on this consideration, we use a product of exp ( − E T s 1 ) and the number of basis states for a sample weight of a sector.

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and long mean free path [9]. These properties make them long sought-after realizations of 1D conductors. In one dimension, repulsive electron-electron interactions lead to an exotic correlated electronic state, the Luttinger liquid (LL) [10, 11]. In a LL, collective plasmon- like excitations give rise to anomalies in the single-particle density of states, and long-**range** order cannot survive even at zero **temperature**. The low-energy theory of SWNTs [12, 13] predicts a metallic SWNT to constitute a realization of a four-channel LL, with channel index a = c+, c − , s+, s − corresponding to total/relative charge/spin degrees of freedom. These arise due to the K − K ′ degeneracy and the electronic spin. The interaction strength

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mark that, in order to obtain an analytical expression for even larger interaction ranges, one should take into account further terms in the approximation above Eq. (C5), which may be- come relevant for sufficiently-small detunings. In any case, such small MS detunings compromise the validity of a pure effective spin **model**, as errors due to a thermal phonon popu- lation start playing a dangerous role 10 .

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Using this macroscopic wave function, this paper describes the derived London equation. In this process, we introduce the concept of an internal toroid and its inductance L. Calculating the value of the above-mentioned inductance L, we introduce an equivalent circuit. Using this equivalent circuit and the PSIM software, the time dependences of the voltages and current on the sample can be found. As a result, the voltage of the sample converging to zero experiences a negative voltage immediately prior to the transition time, which is an evidence of the Meissner effect. Even though the values of the resistances and currents were varied, the result of our **superconductivity** with negative voltages remains.

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[5] Johnston D C, Prakash H, Zachariasen W H, Viswanathan R 1973 **High** **temperature** **superconductivity** in the LiTiO ternary system Materials Research Bulletin 8 777-784 [6] Sleight A W, Gillson J L, Bierstedt P E 1975 **High**-**temperature** **superconductivity** in the BaPb 1-x Bi x O 3 systems Solid State Communications 17 27-28

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shows the influence of pressing **temperature** on the MOE of bagasse and recycled chip binderless particleboard. The MOE improved with the increase of pressing **temperature**. For bagasse particleboard, a peak value of 3.51 GPa was recorded at the pressing **temperature** of 260 °C, which was twice as **high** of that at 200 °C. Recycled chip particle- board showed a peak value of 2.53 GPa at the pressing **temperature** of 280 °C. Both the MOR and MOE values of recycled chip particleboard were about 40 % lower than those of bagasse particleboard at every tested **temperature**. From these results, we conclude that the pressing temper- ature greatly influenced the bending properties of binder- less particleboards, and the optimum condition for the experiment was approximately 260 °C. The raw material type also affected the bending properties of the relevant board; particularly, favorable properties were observed for bagasse. Bagasse binderless particleboard manufactured at 260 °C exceeded the minimum permitted values for the MOE of 3 GPa for grade 18-type particleboard by JIS A 5908 and showed an equivalent value to that of the PMDI particleboard.

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as unconventional superconductor which is nicely matched the location of other NRT superhydrides in the Uemura plot. It is also shown the thermodynamic fluctuations of the order parameter amplitude is dominating factor which limits superconducting transition **temperature** in superhydrides of yttrium.

vertical, 20 **model** levels are used which increase in depth from 10 m in the shallowest layer to 616 m in the deepest layer. A time step of 60 min is employed and the ocean and atmosphere components exchange required fields once per day. The ocean component is based on the Cox (1984) **model**, solving the full primitive equation set in three dimensions. A staggered Arakawa B grid is employed in both atmosphere and ocean models. Sea ice is treated as a zero thickness layer on the surface of the ocean grid. Ice is assumed to form at the base at a freezing point of − 1.8 ◦ C but can also form from freezing in ice leads and by falling snow. A simple pa- rameterisation of sea-ice dynamics is also employed (Gordon et al., 2000) and sea-ice formation due to convergence from drift being limited to 4 m thick. Sea-ice albedo is fixed at 0.8 for temperatures below −10 ◦ C, decreasing linearly to 0.5 at

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of the Sweden KRITZ reactor. To quantify the contribution of each component of the **infinite** multiplication factor to the **temperature** coefficient, calculations were performed for the three configurations of KRITZ benchmark at two temperatures: room **temperature** 20°C and an elevated **temperature** 245°C, using MCNPX which is a continuous energy Monte Carlo reference code for the ed for this work were processed by means of the 4, JENDL-3.3, JEFF-3.1, ENDF/B-VII, and VII.1. The performed studies on the **temperature** coefficient have shown an agreement d those obtained from the final report published by the OECD in 2005

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We can ask the question: should the uncertainty principle be in **high** school curriculum (profile classes)? The answer is affirmative (because of fast nanotechnology developing), but we should strike a happy medium, it means we should arrange a clear way of principle presentation, easily understood by pupils.

After choosing the proper modelling solution by simula- tion, the resulting split-**range** algorithm was tested on the pilot plant. The results of the test measurement can be seen in Figure 13. During the test measurements, similar to the simulation, constant reaction heat was introduced to the reactor with a special loop design for the physical simulation of chemical reactions [11]. The most notable differences between the simulation and test measurement result are caused by the varying temperatures of the monofluid loops of the thermoblock, which remained constant during the simulation. The oscillation between 500 and 1000 seconds, where a near-zero valve opening would be needed, can be explained with the construction of the system and the lag of the control valve in that re- gion.

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The **temperature** of object is essentially a measure of the average energy of thermal motion of molecules and atoms. Heat transformation between molecules and atoms is realized through the interaction of electrons outside the nuc- leus. In traditional theory, the electrons are regarded as the heat conduction and heat radiation messenger or carrier, however, any hot meanings has not been given in itself, in other words, the concept of **temperature** of electron were regarded meaningless. Was that reasonable? Have any proof of electron that should have no **temperature** meaning? In statistical view, the **temperature** relates to a degree of confusion. Electrons are all in doing their own business in order. It doesn’t seem to make sense that the degree of confusion of electrons is almost unchanged after heat effect.

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It is known that a partial substitution (10 percent) of oxygen by fluorine in LaOFeAs accompaned by introduc- tion of additional electrons into the FeAs layer gives rise to **superconductivity**. It can be supposed that each in- troduced electron is paired with one of two unpaired electrons of As 3− participating in formation of 1e bonds. The pair formation breaks the 1e bond, bonding between the ions becomes purely ionic, and Fe 2+ gets an unoccupied electron state. The singlet pair localizes at As 3− and becomes a new unshared pair of As 3− (in addition to the un- shared one in its apical electron state). The bonding of the new pair with As 3− becomes much weaker than that of its parent unpaired electron due to enhanced Coulomb repulsion from the 2e bond pairs present in the As 3− coor- dination polyhedron (Figure 1(b) and Figure 7). It is quite possible that the new pair will even pass from the d 4 s state into a higher-energy As 3− state formed by adding a part of the p state (or even into a new d 4 p state).

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genation takes place only at higher **temperature**. In case when the hydrogenation and de-hydrogenation steps, working at higher temperatures, are excluded in the thermodynamic route at 633 K, the maximum hydrogen absorption is limited to 2.03 mass% lower than the theoretical amount. Hence, relatively **high** holding **temperature** is still necessary to obtain maximum hydrogen absorption equivalent to theoretical capacity for Mg 2 Co without chemical modiﬁcations.

closed, w be an admissible weight function on E, and a be a fixed positive Borel measure defined on E.. We also continue the notation described in Section 2.[r]

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spin state formation and the non-Fermi liquid charac- ter of the normal phase [6]. Unfortunately, details of his original approach, such as suppression of interlayer hopping in the normal phase as the main factor of super- conductivity, seems to contradict experimental data [11]. The latest version of the RVB theory is presented in [12]. We believe, that the main assumption of the strongly correlated limit as the base of understanding the **high**- **temperature** **superconductivity** is correct, as well as em- phasizing a crucial role of spin singlet states, but impor- tant details were missing. Below we present arguments for the thesis, that the minimal object of HTSC-theory is the plaquette in the so-called effective t, t 0 Hubbard **model** [13], rather than the conventional atomic limit typical for the theory of Mott insulators [6, 9]. The best practical realization of this atomic based theory is the dynamical mean-field theory (DMFT) [14]. The obvi- ous minimal generalization in the case of d x 2 −y 2 -wave

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perimental as well as theoretical views. Nowadays, understanding the mechanism of **superconductivity** in such system is one of the challenging research areas. According to reviews on iron based superconductors [2] [3], magnetic interactions are important for understanding the mechanism of **superconductivity**. Experimental ob- servation and theoretical prediction show that knowing the interplay of **superconductivity** and magnetism may suggest the possible mechanism of **superconductivity**.