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Interaction, as an important computing paradigm, is far beyond incremental technological development. Various models such as interaction machines and process algebras have been developed to help design and analyze interaction systems. However, little is reported on the computability theory of interaction, and the design and analysis still have to be performed in an ad hoc way. Hence, the question is: how to uniformly evaluate the power of interaction? Roughly, I plan to explore this question in three steps. The first is to find out a universal formal model for interaction. The second is to abstract the tasks of interaction. The third is to evaluate the capability of interaction in terms of the results of step 1 and 2. The anticipated result may be expressed as a hierarchy that extends Chomsky hierarchy from above. Possible application of the hierarchy is also presented.

Herein, we present a new series of CuI-based hybrid materials with tunable structures and semiconducting properties. The CuI inorganic modules can be tailored into a one-dimensional (1D) chain and two-dimensional (2D) layer and confined/stabilized in coordination frameworks of potassium isonicotinic acid (HINA) and its derivatives (HINA-R, R = OH, NO2, and COOH). The resulting CuI-based hybrid materials exhibit interesting semiconducting behaviors associated with the dimensionality of the inorganic module; for instance, the structures containing the 2D-CuI module demonstrate significantly enhanced photoconductivity with a maximum increase of five orders of magnitude compared to that of the structures containing the 1D-CuI module. They also represent the first CuI-bearing hybrid chemiresistive gas sensors for NO2with boosted sensing performance and sensitivity at multiple orders of magnitude over that of the pristine CuI. Particularly, the sensing ability of CuI-K-INA containing both 1D- and 2D-CuI modules is comparable to those of the best NO2chemiresistors reported thus far.

Rationally designing efficient catalysts for semi-hydrogenation of acetylene is significant but challenging. Herein, Pd isolated single-atom sites (ISAS) on a covalent-organic-framework (COF)-derived nanosphere (Pd-ISAS/CN) are synthesized by a COF-absorption–pyrolysis strategy. This synthetic strategy is also applicable for Pt and Ru ISAS catalysts, demonstrating that it is a general method to synthesize noble-metal ISAS on COF-derived carbon materials. Pd-ISAS/CN exhibits outstanding reactivity and high selectivity for semi-hydrogenation of acetylene, with 92% conversion of acetylene, 80% selectivity toward ethylene at 100 °C, and corresponding activity is as high as 712 molacetylenemolmetal–1h–1. Extended X-ray absorption fine structure (EXAFS) measurement and density functional theory (DFT) calculation reveal the Pd-N1C3sites from Pd-ISAS/CN efficiently boost the reactivity for semi-hydrogenation of acetylene. This work will bring inspiration to rationally design noble-metal-based ISAS catalysts derived from COF materials and boost catalytic performance by optimizing the coordination environment of catalytic sites.

ABSTRACT According to the failure characteristics of asphalt overlay on rigid pavement, a special-purpose test apparatus and method were developed for interlaminar shear fatigue tests to evaluate interlaminar shear fatigue [...]

The Xingmeng orogenic belt is located in the eastern section of the Central Asian orogenic belt, which is one of the key areas to study the formation and evolution of the Central Asian orogenic belt. At present, there is a huge controversy over the closure time of the Paleo-Asian Ocean in the Xingmeng orogenic belt. One of the reasons is that the genetic tectonic setting of the Carboniferous volcanic rocks is not clear. Due to the diversity of volcanic rock geochemical characteristics and its related interpretations, there are two different views on the tectonic setting of Carboniferous volcanic rocks in the Xingmeng orogenic belt: island arc and continental rift. In recent years, it is one of the important development directions in the application of geological big data technology to analyze geochemical data based on machine learning methods and further infer the tectonic background of basalt. This paper systematically collects Carboniferous basic rock data from Dongwuqi area of Inner Mongolia, Keyouzhongqi area of Inner Mongolia and Beishan area in the southern section of the Central Asian Orogenic Belt. Random forest algorithm is used for training sets of major elements and trace elements in global island arc basalt and rift basalt, and then the trained model is used to predict the tectonic setting of the Carboniferous magmatic rock samples in the Xingmeng orogenic belt. The prediction results shows that the island arc probability of most of the research samples is between 0.65 and 1, which indicates that the island arc tectonic setting is more credible. In this paper, it is concluded that magmatism in the Beishan area of the southern part of the Central Asian Orogenic belt in the Early Carboniferous may have formed in the heyday of subduction, while the Xingmeng orogenic belt in the Late Carboniferous may have been in the late subduction stage to the collision or even the early rifting stage. This temporal and spatial evolution shows that the subduction of the Paleo-Asian Ocean is different from west to east. Therefore, the research results of this paper show that the subduction of the Xingmeng orogenic belt in the Carboniferous has not ended yet.

•CBLC levels was elevated in tumor tissues of CRC patients.•CBLC promoted CRC cell proliferation, migration and invasion.•CBLC accelerated tumor growth and promoted tumor metastasis to the lung.•CBLC induced the activation of ERK signaling pathway.•CBLC decreased ABI1 protein levels through its ubiquitin ligase activity.•ABI1 overexpression abolished the effects of CBLC on the tumorigenesis of CRC.

The properties from both bulk phases (magnetism and thermal stability) and surface (composition, orientation, and stability) of iron silicide model compounds were evaluated by a theoretical study with a combination of density functional theory, ab initio atomistic thermodynamics, and Wulff construction. Magnetism, one of the properties originated from bulk phases, has been chosen as an example to demonstrate how to correlate it with the local chemical environment to provide an in-depth understanding. We found that increasing the number of coordinative Si atoms adjacent to an Fe center would cause a decrease in magnetic moment. To reveal surface structural features relevant to surface properties of iron silicides, we evaluated the influence of Si chemical potential (μSi) on surface thermal stability over a range of temperature (T) and partial pressure of SiH4(PSiH4). It turns out that the thermal stability of the Si-rich surfaces has been improved with increasing μSiunder high Tand PSiH4. We then acquired the surface free energy of all possibly exposed facets, built up reasonable crystalline models via Wulff construction, and thereby systematically assessed morphology evolution of all of the Fe–Si models as a function of changing Tand PSiH4. We found that low Miller index facets are more likely to be exposed with the rising Tand PSiH4.

Carbon–carbon bond-forming reductive elimination from elusive organocopper(III) complexes has been considered the key step in many copper-catalyzed and organocuprate reactions. However, organocopper(III) complexes with well-defined structures that can undergo reductive elimination are extremely rare, especially for the formation of Csp3–Csp3bonds. We report herein a general method for the synthesis of a series of [alkyl-CuIII-(CF3)3]−complexes, the structures of which have been unequivocally characterized by NMR spectroscopy, mass spectrometry, and X-ray crystal diffraction. At elevated temperature, these complexes undergo reductive elimination following first-order kinetics, forming alkyl-CF3products with good yields (up to 91%). Both kinetic studies and DFT calculations indicate that the reductive elimination to form Csp3–CF3bonds proceeds through a concerted transition state, with a ΔH⧧= 20 kcal/mol barrier.

The stability of β-Mo2C surfaces has been computed at the level of density functional theory under the consideration of the temperature, pressure, and molar ratios of CH4/H2and CO/CO2gas mixtures by using ab initio atomistic thermodynamic calculations. It was found that the (001) surface is most stable at low temperature, whereas (101) becomes dominant at high temperature with CH4as carbon source, and the computed surface stability is supported by the experimental X-ray diffraction pattern and intensity. For CO as carbon source, the (101) surface has the smallest surface Gibbs free energy at temperatures up to 1000 K and is most stable. On the basis of the Wulff-type particle shapes from surface Gibbs free energies the (101) facet represents the largest surface area of β-Mo2C. Our findings are in perfect agreement with the results of high-resolution transmission electron microscopy.