Samples of laser powder bed processed AlSi10Mg have been examined using scanning electron microscopy (SEM), transmission electron microscopy (TEM), and scanning TEM so that the complex ...microstructures of as-fabricated samples could be characterised. In longitudinal sections, columnar Al grains, about 10 μm in diameter, dominate the microstructure, but some equiaxed regions are seen. The columnar grains are made up of long cells, about 500 nm in width, rather than dendrites, which are separated from adjacent identical orientation long cells and from non-parallel cells at Al grain boundaries, by Al-Si eutectic. There is a substructure on the scale of 300–500 nm, of identical orientation “sub-cells” throughout the length of the long cells also separated by regions of the Al-Si eutectic. Microdiffraction is necessary to distinguish between cell boundaries, sub-cell boundaries and grain boundaries. The “cell-like” structures observed in cross section samples are cross sections of these long cells and of the Al-Si eutectic at cell boundaries. Deformed as-fabricated samples have been examined in TEM to assess the role of Si particles within the cells and of the Al-Si-eutectic boundaries on the response of SLMed samples to plastic deformation. In addition in situ compression tests in a TEM have been carried out which show that cell boundaries, sub-cell boundaries and particles within the cells limit dislocation movement during deformation.
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Logical qubit encoding and quantum error correction (QEC) protocols have been experimentally demonstrated in various physical systems with multiple physical qubits, generally without reaching the ...break-even point, at which the lifetime of the quantum information exceeds that of the single best physical qubit within the logical qubit. Logical operations are challenging, owing to the necessary non-local operations at the physical level, making bosonic logical qubits that rely on higher Fock states of a single oscillator attractive, given their hardware efficiency. QEC that reaches the break-even point and single logical-qubit operations have been demonstrated using the bosonic cat code. Here, we experimentally demonstrate repetitive QEC approaching the break-even point of a single logical qubit encoded in a hybrid system consisting of a superconducting circuit and a bosonic cavity using a binomial bosonic code. This is achieved while simultaneously maintaining full control of the single logical qubit, including encoding, decoding and a high-fidelity universal quantum gate set with 97% average process fidelity. The corrected logical qubit has a lifetime 2.8 times longer than that of its uncorrected counterpart. We also perform a Ramsey experiment on the corrected logical qubit, reporting coherence twice as long as for the uncorrected case.Repeated error correction creates a logical qubit encoded in the hybrid state of a superconducting circuit and a bosonic cavity, which is shown to be fully controllable under a universal single-qubit gate set.
Sorption thermal storage for solar energy Yu, N.; Wang, R.Z.; Wang, L.W.
Progress in energy and combustion science,
10/2013, Letnik:
39, Številka:
5
Journal Article
Recenzirano
Sorption technologies, which are considered mainly for solar cooling and heat pumping before, have gained a lot of interests for heat storage of solar energy in recent years, due to their high energy ...densities and long-term preservation ability for thermal energy. The aim of this review is to provide an insight into the basic knowledge and the current state of the art of research on sorption thermal storage technologies. The first section is concerned with the terminology and classification for sorption processes to give a clear scope of discussion in this paper. Sorption thermal storage is suggested to cover four technologies: liquid absorption, solid adsorption, chemical reaction and composite materials. Then the storage mechanisms and descriptions of basic closed and open cycles are given. The progress of sorption materials, cycles, and systems are also reviewed. Besides the well-known sorbents like silica gels and zeolites, some new materials, including aluminophosphates (AlPOs), silico-aluminophosphates (SAPOs) and metal-organic frameworks (MOFs), are proposed for heat storage. As energy density is a key criterion, emphais is given to the comparison of storage densities and charging tempertures for different materials. Ongoing research and development studies show that the challenges of the technology focus on the aspects of different types of sorption materials, the configurations of absorption cycles and advanced adsorption reactors. Booming progress illustrates that sorption thermal storage is a realistic and sustainable option for storing solar energy, especially for long-term applications. To bring the sorption storage solution into market, more intensive studies in fields of evaluation of advanced materials and development of efficient and compact prototypes are still required.
We show that it is possible to use gravitational wave detectors to observe the occurrence of a first order phase transition in Pati-Salam extensions of the Standard Model. We show that the peak ...frequency of the expected gravitational wave signals ranges within 0.1–10 Hz. We find amusing that the next generation of gravity waves detectors are able to explore time-honored extensions of the Standard Model occurring at energy scales inaccessible by present and future particle physics accelerators.
The dispersive sweep of fast radio bursts (FRBs) has been used to probe the ionized baryon content of the intergalactic medium
, which is assumed to dominate the total extragalactic dispersion. ...Although the host-galaxy contributions to the dispersion measure appear to be small for most FRBs
, in at least one case there is evidence for an extreme magneto-ionic local environment
and a compact persistent radio source
. Here we report the detection and localization of the repeating FRB 20190520B, which is co-located with a compact, persistent radio source and associated with a dwarf host galaxy of high specific-star-formation rate at a redshift of 0.241 ± 0.001. The estimated host-galaxy dispersion measure of approximately Formula: see text parsecs per cubic centimetre, which is nearly an order of magnitude higher than the average of FRB host galaxies
, far exceeds the dispersion-measure contribution of the intergalactic medium. Caution is thus warranted in inferring redshifts for FRBs without accurate host-galaxy identifications.
Aims
The objective of this study was twofold: (i) to examine the effect of Clostridium butyricum on intestinal barrier function and (ii) to elucidate the mechanisms involved in enhanced intestinal ...barrier function.
Methods and Results
Forty‐eight weaned piglets were assigned randomly to either a basal diet or a C. butyricum‐supplemented diet. On day 15, all pigs were orally challenged with enterotoxigenic Escherichia coli (ETEC) K88 or saline. Clostridium butyricum decreased serum diamine oxidase activity and d‐lactic acid concentration, as well as increased intestinal tight junction proteins (ZO‐1, claudin‐3 and occludin) expression in ETEC K88‐infected pigs. Moreover, C. butyricum decreased IL‐1β and IL‐18 levels in serum and gut, whereas it increased IL‐10 levels. Furthermore, C. butyricum downregulated NLRP3 and caspase‐1 expression in ETEC K88‐challenged pig gut, but did not affect apoptosis‐associated speck‐like protein expression.
Conclusions
Clostridium butyricum enhanced intestinal barrier function and inhibited apoptosis‐associated speck‐like protein‐independent NLRP3 inflammasome signalling pathway in weaned piglets after ETEC K88 challenge.
Significance and Impact of the Study
The novelty of this study lies in the beneficial effects of C. butyricum on intestinal health, likely by improving intestinal barrier function and alleviating inflammatory reactions.
A mandrel winding method, which can realize remarkable homogeneous plastic deformation at room temperature for various metallic glasses, is applied to characterize plastic flow units and study their ...relationship with macroscopic deformations and relaxations. The method can provide information on the activation energy, activation time, size, intrinsic relaxation time, distribution, and density of flow units. We find the plasticity of a metallic glass can be controlled through modulating the features of flow units. The results have benefits for better understanding the structural origins of deformations and relaxations, and for designing metallic glasses with improved performances.
Bacterial diseases of crabs: A review Wang, W.
Journal of invertebrate pathology,
2011, 2011-Jan, 2011-1-00, 20110101, Letnik:
106, Številka:
1
Journal Article
Recenzirano
Bacterial diseases of crabs are manifested as bacteremias caused by organisms such as
Vibrio,
Aeromonas, and a Rhodobacteriales-like organism or tissue and organ tropic organisms such as ...chitinoclastic bacteria, Rickettsia intracellular organisms, Chlamydia-like organism, and
Spiroplasma. This paper provides general information about bacterial diseases of both marine and freshwater crabs. Some bacteria pathogens such as
Vibrio cholerae and
Vibrio vulnificus occur commonly in blue crab haemolymph and should be paid much attention to because they may represent potential health hazards to human beings because they can cause serious diseases when the crab is consumed as raw sea food. With the development of aquaculture, new diseases associated with novel pathogens such as spiroplasmas and Rhodobacteriales-like organisms have appeared in commercially exploited crab species in recent years. Many potential approaches to control bacterial diseases of crab will be helpful and practicable in aquaculture.
The broaching of fluid through cement sheath imposes serious challenges to the integrity of the wellbore. Wellbore integrity is highly dependent upon the integrity of the interfacial bonding of the ...cement to the formation and casing. We developed a workflow to utilize three-dimensional numerical analysis to simulate propagation of cement failures due to fluid leakage at the casing shoe. The excessive fluid pressure provided by the leakage is the driving force for the cement failure. The interfaces of the cement sheath with the formation and casing are potential paths for growth of delamination cracks. These paths are represented by pre-inserted cohesive elements. Existence of non-uniform failure pattern around the wellbore is shown for different in situ stress conditions and cement properties. These spatial failure patterns cannot be predicted by traditional two-dimensional models. Our simulations show the significant role of radial and tangential stress on failure propagations, but shear stress has a significant effect on failure initiations. Furthermore, the possibility of fracture containment and broaching is investigated by sensitivity analysis of cement interface properties. From these sensitivity tests, normal (and shear) strength of the interface, and in situ stresses have been considered as major factors for fracture containment. It is found that larger values of cohesive interface normal (shear) strength, or the rigidness of the cement can effectively reduce the likelihood of failure around the wellbore. The presented model provides a systematic approach to understand and assess wellbore integrity in design and production stages.
•Wellbore integrity problem is treated as a fluid driven cylindrical crack.•Cohesive interface method is utilized to model cement interface behavior.•An approach to derive cohesive element parameters is demonstrated.•Dimensional analysis for wellbore integrity failure is performed.
The high-entropy alloys are defined as solid-solution alloys containing five or more than five principal elements in equal or near-equal atomic percent. The concept of high mixing entropy introduces ...a new way for developing advanced metallic materials with unique physical and mechanical properties that cannot be achieved by the conventional microalloying approach based on only a single base element. The metallic glass (MG) is the metallic alloy rapidly quenched from the liquid state, and at room temperature it still shows an amorphous liquid-like structure. Bulk MGs represent a particular class of amorphous alloys usually with three or more than three components but based on a single principal element such as Zr, Cu, Ce, and Fe. These materials are very attractive for applications because of their excellent mechanical properties such as ultrahigh (near theoretical) strength, wear resistance, and hardness, and physical properties such as soft magnetic properties. In this article, we review the formation and properties of a series of high-mixing-entropy bulk MGs based on multiple major elements. It is found that the strategy and route for development of the high-entropy alloys can be applied to the development of the MGs with excellent glass-forming ability. The high-mixing-entropy bulk MGs are then loosely defined as metallic glassy alloys containing five or more than five elements in equal or near-equal atomic percent, which have relatively high mixing entropy compared with the conventional MGs based on a single principal element. The formation mechanism, especially the role of the mixing entropy in the formation of the high-entropy MGs, is discussed. The unique physical, mechanical, chemical, and biomedical properties of the high-entropy MGs in comparison with the conventional metallic alloys are introduced. We show that the high-mixing-entropy MGs, along the formation idea and strategy of the high-entropy alloys and based on multiple major elements, might provide a novel approach in search for new MG-forming systems with significances in scientific studies and potential applications.
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