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The structure of the Tajik Basin is characterized by a series of NE-trending fold-thrust belts that share a common detachment layer composed of Upper Jurassic evaporite rocks. These fold-thrust structures, thrusting face to face, converge toward the Vakhsh Depression. Due to limitations of seismic and drilling data, the controlling factors of the formation of the fold-thrust belts in the Tajik Basin remain controversial. Taking the Tajik Basin as a geological prototype, structural physical simulation experiments were conducted to decipher the controlling factors of salt-related structure deformation. The experiment results indicate that the tectonic deformation of the strata above the Jurassic evaporite rocks in the Tajik Basin is mainly controlled by the detachment layer of the Upper Jurassic evaporite rocks. The early salt diapirs in the Upper Jurassic played a key role in the formation of the thrust belts. Additionally, tectonic stress near the mountain front was rapidly transmitted to the inner basin due to the load of the structural wedge. Based on the results of physical simulation experiments, we speculate that the tectonic deformation of the subsalt strata and the basement in the Tajik Basin is primarily controlled by a deep detachment layer. The deformation of the subsalt strata is relatively gentle, which is conducive to the formation of large-scale, broad and gentle anticlinal structures. The anticlinal structures of the subsalt strata can form effective traps due to the sealing effect of the Upper Jurassic evaporite layer, offering promising exploration potential.

The effect of different solution temperatures (1140, 1160 ℃ and 1180 ℃) and cooling conditions (AC, FC-900 ℃+AC, FC) on the microstructures and mechanical properties of K439B alloy were investigated using metallographic microscopy and field emission scanning electron microscopy (FE-SEM). The results show that the optical microstructures and morphology of γ' precipitates are similar and the width of grain boundary slightly increases after increasing the solution temperature. When cooled with AC, γ' precipitates are uniformly distributed and the average size is 50.7 nm; when cooled with FC-900 ℃+AC, the larger γ' precipitates of 250-510 nm are precipitated at the interdendritic area region and near the grain boundary, exhibiting a bimodal γ' microstructure; when cooled with FC, the volume fraction of larger γ' precipitates increases and the content of granular M23C6 carbides at grain boundary improves. The stress rupture life of K439B alloy at 815 ℃/379 MPa is enhanced after reducing the cooling rate, while different solution parameters have little effect on the room-temperature tensile property.

[Objective] Precipitation is the main source of soil water in arid and semi-arid regions. By combining field observation and model simulation to study the regularity of rainfall infiltration, the soil water deficit can be mastered more systematically. [Methods] Through fixed point observation, the Hydrus-1d model was applied to simulate the dynamic change of soil water in Platycladus orientalis on the artificial of Nanshan Mountain in Lanzhou, evaluate the applicability of the model in arid region, and analyze the soil water response and infiltration mechanism under different rainfall conditions. [Results] The Hydrus-1d model had good applicability in the artificial side of Nanshan in Lanzhou, and the deep simulation effect was better. When the rainfall was less than 30 mm, the soil moisture content at 10 cm has the strongest response to rainfall, while the influence of rainfall at 30 and 50 cm was relatively small and had an obvious lag, and there was no response below 70 cm. There was a wetness peak when the rainfall was more than 8.2 mm. During the simulation period, the maximum infiltration depth was 70 cm and the maximum infiltration volume was 23.7 mm. The infiltration depth increased with time, while the infiltration volume and infiltration rate decreased with time. Rainfall was positively correlated with infiltration volume, infiltration depth and infiltration rate (p

In this article, we design a family of scale-free networks and study its random target access time and weighted spanning trees through the eigenvalues of transition weight matrix. First, we build a type of fractal network with a weight factor rr and a parameter mm. Then, we obtain all the eigenvalues of its transition weight matrix by revealing the recursive relationship between eigenvalues in every two consecutive time steps and obtain the multiplicities corresponding to these eigenvalues. Furthermore, we provide a closed-form expression of the random target access time for the network studied. The obtained results show that the random target access is not affected by the weight; it is only affected by parameters mm and tt. Finally, we also enumerate the weighted spanning trees of the studied networks through the obtained eigenvalues.

It is known that there are no polynomial quantum algorithms to solve some lattice difficult problems. Uncolored graphic lattice and colored graphic lattice are the products of multidisciplinary intersection inspired by lattice theory. A uncolored graphic lattice or a colored graphic lattice in topological coding is based on some graph operations and a set of disjoint connected graphs or disjoint connected colored graphs. Based on password authentication or digital file encryption, this paper introduces the number-based string topological authentication problem, and gives an asymmetric encryption system by topological coding. Topological coding can form an asymmetric encryption system with one public key corresponding to two or more private keys and, more public keys corresponding to more private keys. Topology authentication in topology coding requires two different fields of mathematical knowledge and can produce exponential level algorithm. Based on the edge-joining operation and vertex-coinciding operation of graphs, the existence of colored graphic lattice admitting graceful total colorings is shown, and graphic lattice and F-graphic lattice are established with infinite elements closed to graceful total coloring. Topological vectors for special coloring graphs are defined, and a connection between graphic lattice and non-negative integer traditional lattice is built up to provide a feasible technique for quantum resistance calculation, since there is no polynomial algorithm for solving number-based strings up to now. Because graph isomorphism problem is NP-hard, topological coding lattice has the function of resisting supercomputer and quantum computer.

The microstructures and mechanical properties of Inconel 718 alloy were analyzed by using 982 ℃ water cooled solid solution bar after repeated solution and re-aging treatment, and compared with direct aging treatment.The effects of repeated solution treatment temperatures ranging from 941 to 1010 ℃ on microstructures and mechanical properties of the alloy were systematically studied. The results show that with the increase of repeated solution temperature, the content of γ′′ phase / δ phase gradually increases / decreases with no obvious change in grain size, leading to an evident improvement on room-temperature hardness, high-temperature tensile strength and stress-rupture life of the alloy. The maximum values of the tensile elongation and the stress rupture ductility are reached at the repeated solution temperature of 982 ℃. As compared to the direct aging treatment condition, there is no apparent change in microstructure and mechanical properties of the alloy aged after the repeated solution treatment at 982℃. On the contrary to the higher repeated solution temperature, the lower repeated temperature produces unfavorable effect on the mechanical properties.

The purpose of the present study was to evaluate the role of co-treatment of rosuvastatin (RSV) and dapagliflozin (DGZ) preconditioning in myocardium ischemia/reperfusion (I/R) injury and to further investigate the underlying mechanism.

BackgroundThe interstitial atoms in nuclear graphite of the reactor will lead to the change of the properties and structure of the nuclear graphite. However, the migration and configuration of interstitial atoms in nuclear graphite are not well understood.PurposeThis study aims to clarify the migration and combination mechanism of interstitial atoms in nuclear graphite by First-principles calculation.MethodIn this research, the Vienna Ab-initio Simulation Package was used to calculate the properties of the system. First-principles calculation was used to study the interaction between interstitial atoms and the migration and combination behavior of interstitial atoms. The diffusion energy barrier was estimated by the climbing image nudge elastic band (CI-NEB) method.ResultsThere is a gravitational force between the interstitial atoms on the same graphite sheet, but it can be negligible while the distance between two interstitial atoms is greater than 0.5 nm. The interstitial atoms tend to migrate and combine along the armchair direction. The combination of two interstitial atoms reduces the structural energy by about 6.0 eV. The energy barrier of the entire migration and combination is about 0.4 eV during the migration process.ConclusionThe most stable cluster structure of interstitial atoms in graphite is the chain-like structure, and the secondary is the spiro structure of the closely adjacent interstitial atoms. When the number of interstitial atoms is more than 6, the structure of interstitial atoms exists as a cluster containing six-membered carbon rings and stacked with the bottom surface vertically into an AB configuration. If more interstitial atoms are combined, a new graphite sheet will eventually be formed.

Continuous cleaning process of the molten copper slags in a channel reactor under a vertical electric field is proposed. The copper-matte settling velocity under the vertical electric field is much faster than that only under the gravity in the molten slags, and the electric field can also accelerate the magnetite reduction. Cu content in the slag can fall below 0.35 wt. % during the continuous cleaning process, which exceeds much more existing slag treatment process. In addition, the behaviours of some other heavy metal elements in the molten slags during the continuous process are also discussed.

Abstract Though much research has been conducted for nanoparticles, naturally occurring nanoparticles have not yet been well explored for their diverse properties and potential applications. This paper reports the optical absorption and scattering properties of nanoparticles secreted by English ivy. Both experimental and theoretical studies have been conducted. Strong ultraviolet extinction and excellent visible transparency are observed, compared to the inorganic TiO2 and ZnO nanoparticles at similar concentrations. The contributions of absorption and scattering to the total extinction are quantified by simulation of the Mie scattering theory.