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In this work, the gravitational field is investigated in detailed and the quantum mechanics equation under the gravitational field has been derived. Then, the Schrodinger and Dirac equations are accordantly solved under the gravitational field condition by separating variables. As a result, the Rydberg formula is deduced in such conditions, which proves that the change of the external gravitational field intensity will cause the overall spectral movement. Obviously, the partial redshift of quasar spectrum should assign to this effect. Furthermore, by applying this gravitational field together with the energy and mass concepts into the symmetry, gravity theory and gauge theory, it is deduced that the interaction of “gravity” between matter and anti-matter is repulsive force, which is the originator of the accelerated expansion phenomenon for dark energy in the universe. It is found that the calculated cosmological constant is a small variable related to the radial and angular direction of the universe, and the “spontaneous breaking of vacuum symmetry” is caused by this gravitational field. Further, the gravitational field lead to the non-conservation of weak action parity. The equal number of baryon and antibaryon as well as the energy conservation in the universe are confirmed. In this work, the gravitational field is introduced into quantum theory, which will promote the integrality of the quantum mechanics, and explain the dark energy phenomenon constitutionally. This study will push the astrophysical theory and the gauge theory of particle physics for the further study of energy level, basic particle structure, and quantum gravity theory.

Components and crystal structures of the intermetallic phases in a gravity die-cast Mg−6.0Zn−1.5Nd−0.5Zr (wt%) alloy were investigated using transmission electron microscopy. The results indicate that this alloy has multiple intermetallic phases and various inner faults. Totally, six eutectoid intermetallic phases, namely W (MgNdZn3), T (Mg39Zn55Nd6), (Mg,Zr)Zn2, Z (Mg28Zn65Nd7), H2 (Mg15Zn70Nd15), and H1 (Mg24Zn64Nd11), were simultaneously observed at grain boundaries, and six precipitates (Z, Mg7Zn3, T, Mg4Zn7, β1′-MgZn2 and β2′-MgZn2) were found in α-Mg grains. Furthermore, faults like sub-grain boundaries, orientation domains (coherent with the same matching plane but with different orientations), stacking faults and twins were observed in the eutectoid intermetallic phases. Finally, some new orientation relationships between the known intermetallic phases were revealed. This paper can provide new insight into alloy design for Mg−Zn−RE (RE: rare earth) based alloys.

Twinning and precipitation play important roles in deformation and strengthening of magnesium alloys. In this work, interfacial precipitation in {10 1 ¯ 2} twin boundaries (TBs) of a cold-stamped Mg−12Gd−1.2Zn−0.4Zr alloy was investigated using atomic-resolution high-angle annular dark-field scanning transmission electron microscopy. Extended periodic segregation of Gd + Zn atoms in the ~86.2° {10 1 ¯ 2} TBs with basal-prismatic facets and in the symmetric tilting TBs (obviously > 86.2°) frequently occurred, resulted in the formation of new interfacial phases, namely βTB’ having a monoclinic structure in the TBs with two segregation layers and βTB having a tetragonal structure in the TBs with three or more segregation layers. The formation of βTB clearly accelerates peak-aging and improves the alloy's strength.

The emerging polyethylenimine (PEI)-functionalized solid adsorbents have witnessed significant development in the implementation of CO2 capture and separation because of their decent adsorption capacity, recyclability, and scalability. As an indispensable substrate, the importance of selecting porous solid supports in PEI functionalization for CO2 adsorption was commonly overlooked in many previous investigations, which instead emphasized screening amine types or developing complex porous materials. To this end, we scrutinized the critical role of different commercial porous supports (silica, alumina, activated carbon, and polymeric resins) in PEI impregnation in this study, taking into account multiple perspectives. Hereinto, the present results identified that abundant larger pore structures and surface functional groups were conducive to loading a considerable amount of PEI molecules. Various supports after PEI functionalization had great differences in adsorption capacities, amine efficiencies, and the corresponding optimal temperatures. In addition, more attention was paid to the role of porous supports in long-term stability during the consecutive adsorption-regeneration cycles, while N2 and CO2 purging as regeneration strategies, respectively. Especially, CO2-induced degradation due to urea species formation was specifically recognized in a SiO2-based adsorbent, which would induce serious concerns in CO2 cyclic capture. On the other side, we also confirmed that adopting conventional porous supports, for example, HP20, could achieve superior adsorption performance (above 4 mmol CO2/g) and cyclic stability (around 1% loss after 30 cycles) rather than the ones synthesized through complex approaches, which ensured the availability and scalability of PEI-functionalized CO2 adsorbents.

As a narrow band gap semiconductor, wurtzite β-CuGaO2 has drawn increasing attention in the area of solar energy. Although β-CuGaO2 has been theoretically predicted to possess ferroelectric polarization, its experimental ferroelectric characterization and practical applications have not yet been presented. Herein, firstly we experimentally confirmed its ferroelectric property via hysteresis loop measurement. The result showed a remanent polarization value of 10.20 μC·cm−2 with low coercive electric field of 6.45 kV·cm−1 at 20 Hz at room temperature, while the leakage current density (J) value was found to be 1.188 A·cm−2, which suggested the property of a larger remnant polarization with low coercive electric field than current value if the compactness was strengthened. Then, the synergistic effect of ferroelectric and semiconductor was comparatively highlighted by the experiment of pollutant degradation. Within 30 min, methyl orange degradation efficiency had reached 30.73% only in the case of spontaneous polarization (electricity), while it could reach 67.58% under the effect of pre-polarized β-CuGaO2 powder due to the modulating orientation of ferroelectric domains. Once irradiated (light), it was up to 92% within 30 min; in comparison, it merely took 16 min up to 92% degradation efficiency under both illumination and pre-polarization. If without illumination, it was 92.01% with 30 min in the condition of ordinary ultrasonic vibration (force) while under both illumination and ultrasonic vibration, only 11 min was spent to reach 92.79% degradation efficiency. All these results felicitously indicated that β-CuGaO2 had fascinating potential in energy harvesting (such as electricity, light, force) and transformation as wastewater environment remediation catalyst.

Long non-coding RNAs (lncRNAs), microRNAs (miRNAs or miRs), and genes are emerging players in cancer progression. In the present study, we explored the roles and interactions of oncogenic lncRNA small nucleolar RNA host gene 1 (SNHG1), miR-376, forkhead box protein K1 (FOXK1), and Snail in hepatocellular carcinoma (HCC). Expression of SNHG1, miR-376, and FOXK1 in HCC was characterized in clinical HCC tissues of 75 patients with HCC. The interactions between SNHG1 and miR-376 and between miR-376 and FOXK1 were predicted and confirmed by dual-luciferase reporter gene and RNA immunoprecipitation assays. Overexpression and knockdown experiments were performed in HCC cells to examine the effects of the SNHG1/miR-376/FOXK1/Snail axis on viability, apoptosis, invasiveness, and migrating abilities. Their effects on tumor growth and metastasis were validated in nude mouse models. SNHG1 and FOXK1 were upregulated, and miR-376a was downregulated in HCC. SNHG1 knockdown contributed to suppression of HCC cell viability, invasion, and migration properties and promotion of apoptosis. SNHG1 could competitively bind to miR-376a to upregulate its target gene FOXK1, which upregulated Snail. SNHG1 knockdown delayed cancer progression both in vitro and in vivo by upregulating miR-376a and downregulating FOXK1 and Snail. SNHG1 knockdown exerts anti-tumor activity in HCC, suggesting a therapeutic target., Graphical Abstract, SNHG1 is highly expressed in HCC. SNHG1 competitively binds to miR-376a and inhibits the expression of miR-376a, thereby promoting FOXK1 and Snail expression, leading to reduction of HCC cell proliferative, migrating, and invasive properties, and promotes cell apoptosis and promotion of tumor growth and metastasis in HCC.

The development of multiphase composite electrocatalysts plays a key role in achieving the efficient and durable operation of intermediate-temperature solid oxide fuel cells (IT-SOFCs). Herein, a self-assembled nanocomposite is developed as the oxygen reduction reaction (ORR) catalyst for IT-SOFCs through a coprecipitation method. The nanocomposite is composed of a doped (Mn0.6Mg0.4)0.8Sc0.2Co2O4 (MMSCO) spinel oxide (84 wt %), an orthorhombic perovskite phase (11.3 wt %, the spontaneous combination of PrO2 additives and spinel), and a minor Sc2O3 phase (4.7 wt %). The surface of the (Mn0.6Mg0.4)0.8Sc0.2Co2O4 phase is activated by the self-assembled nanocoating with many heterogeneous interfaces. Thence, the ORR kinetics is obviously accelerated and an area-specific resistance (ASR) of ∼0.11 Ω cm2 is obtained at 750 °C. Moreover, a single cell with the cathode shows a peak power density (PPD) of 1144.1 mW cm-2 at 750 °C, much higher than that of the cell with the MnCo2O4 cathode (456.2 mW cm-2). An enhanced stability of ∼120 h (0.8 A cm-2, 750 °C) is also achieved, related to the reduced thermal expansion coefficient (13.9 × 10-6 K-1). The improvement in ORR kinetics and stability can be attributed to the refinement of grains, the formation of heterointerfaces, and the enhancement of mechanical compatibility.

In recent years, global warming has become an important topic of public concern. As one of the most promising carbon capture technologies, solid amine adsorbents have received a lot of attention because of their high adsorption capacity, excellent selectivity, and low energy cost, which is committed to sustainable development. The preparation methods and support materials can influence the thermal stability and adsorption capacity of solid amine adsorbents. As a supporting material, it needs to meet the requirements of high pore volume and abundant hydroxyl groups. Industrial and biomass waste are expected to be a novel and cheap raw material source, contributing both carbon dioxide capture and waste recycling. The applied range of solid amine adsorbents has been widened from flue gas to biogas and ambient air, which require different research focuses, including strengthening the selectivity of CO

Biodrying is a promising method that produces bio-stabilized output with minimum pretreatment requirements. In this study, a hot-air supply system was added to the traditional biodrying process for kitchen waste, which showed significant reduction in moisture content in 5 days (maximum reduction of 37.45%). A series of experiments was conducted to optimize the hot-air biodrying system utilizing different aeration rates, temperatures, and mixing ratios of feedstock to bulking agents. The results showed that a 65 °C aeration temperature led to the highest water removal rate and low volatile solids consumption rate, with the biodrying index reaching 4.9 g water per gram of volatile solids. On the other hand, evaluation of the overall biodrying efficiency based on the weight loss and bio-stabilization showed that intermittent aeration temperature at 55 °C performed best, offering suitable conditions for water evaporation and bio-degradation. In combination with a flow rate of 0.8 L/kg*min and 1:1 mixing ratio, these conditions resulted in the maximum volatile solids consumption of 26.26% in 5 days. The volatile solids consumption and 34.47% water removal rate of the trial had contributed to a total of 64.13% weight loss. The weight loss was even higher than that of a conventional biodrying system which was conducted for more than 14 days.

A newly developed Mg-4Zn-2La-3Y alloy with high strength was fabricated by high-pressure die casting method, and its microstructures were thoroughly studied using transmission electron microscopy. The results demonstrate that it owns fine grains and approximately highly interconnected intermetallic phase skeletons, and exhibits ultra-high strength at both room and high temperatures. Interestingly, the eutectic intermetallic skeleton of this alloys is consisted of numerous fine particles, which are mainly consisted of two intermetallic phases, namely W and Mg12RE. Multiple {101} twins and SFs were found in the Mg12RE phase while a few of SFs in the W phase. Additionally, minor long-period stacking ordered phase was observed in the eutectoid phase, and it probably nucleated on the Mg12RE phase following a certain OR as (0002)14H//(110)Mg12RE and [ 11 2 ¯ 0 ]14H//[ 1 1 ¯ 1 ¯ ]Mg12RE, or (0002)14H//(211)Mg12RE and [ 11 2 ¯ 0 ]14H//[ 1 1 ¯ 1 ¯ ]Mg12RE. This special intermetallic skeleton with many interfaces and planar faults can efficiently transfer dislocations across grain boundaries, and this is the key factor for the outstanding mechanical properties of the studied alloy.

Herbaceous peony is a promising oilseed crop. ‘Hangshao’ and ‘Fenghuang Niepan’ are two cultivars with high yield and oil content. In this study, seed reserved nutrient of these two genotypes were investigated during seed development process. Results showed that ‘Hangshao’ and ‘Fenghuang Niepan’ matured approximately 85 ​d after flowering (DAF). The development process could be divided into four stages: seed formation and enlargement stage (S1), seed inclusion and enrichment stage (S2), crude fat rapid accumulation stage (S3) and dehydration and color transition stage (S4). During this process, 100-seed fresh weight (HFW) and 100-seed dry weight (HDW) increased, whereas water content (WC) decreased. HFW, HDW and WC for ‘Hangshao’ seed at 85 DAF were 28.56 g, 20.78 ​g and 37.50% respectively, whereas those for ‘Fenghuang Niepan’ seed were 27.2 ​g, 19.78 ​g, and 30.85% respectively. In terms of the primary metabolites measuring, soluble protein content was consistently low (only 2.24%–3.15%), while starch content was relatively high (5.60%–24.81%). They displayed a trend of gradual increasing in early stage, followed by rapid decline. Crude fat tended to accumulate continuously with a linear upward trend starting at 40 DAF, and its maximum level was reached at 85 DAF (27.57% for ‘Hangshao’ and 29.57% for ‘Fenghuang Niepan’). For the secondary metabolites determination, total phenols content was relatively steady, maintaining at 107.7–129.9 ​mg/g for both cultivars, while total flavonoids content varied within 25.33–65.33 ​mg/g for ‘Hangshao’ and 24.33–52.37 ​mg/g for ‘Fenghuang Niepan’. The maximum level for both cultivars occurred at 55 DAF. Furthermore, crude fat content was found to be highly correlated with WC by correlation analysis and linear regression model definition (P ​≤ ​0.01 and r ​= ​0.954). Thus, WC was recommended for evaluating crude fat in peony seed. These findings could provide scientific reference for high-yielding production practice for oleaginous peony plant.

Because the valence state of metal with variable valences is sensitive to oxidation atmosphere, it is difficult to fabricate single-phased metal oxide with intermediate valence by vapor or vacuum deposition. In this work, the copper valence state in oxides was controlled by introducing a nitrogen flow into the sputtering chamber. The surface chemical potential of oxygen can be efficiently tuned through adsorption competition on the growth surface. The transition process from CuO–Cu2O mixture to single Cu2O was observed with increasing the nitrogen flow rate. For the single-phased Cu2O, the hole concentration was tuned in a range of 2.6 × 1017 to 1.1 × 1018 cm−3.

Pyrolysis characteristics of chemical extraction microalgae residue in the presence and absence of catalysts (KCl, KOH, K2CO3, Al2O3, CaO, MgO and pyrolysis char of microalgae residue) were evaluated using a thermal analyzer and a tube furnace reactor. These catalysts can effectively improve the oil yield during microalgae residue pyrolysis. The order of the strength on increasing the oil yield was: pyrolysis char of microalgae residue > Al2O3>CaO > K2CO3>MgO > KCl > KOH. The addition of all the catalysts can effectively reduce the potential ecological risk of heavy metals in pyrolysis chars. The addition of KCl, MgO and Al2O3 can increase the content of gasoline components in pyrolysis oil. All the catalysts can reduce the content of CO2 in the pyrolysis gas, and increase the content of CO and hydrocarbon gases. KCl addition showed considerable increase in both yield and quality of pyrolysis oil and gas with a proportion of 5 wt % during microalgae residue pyrolysis.

Pyrolysis characteristics of microalgae (MA) and its chemical extraction residue (MR) were evaluated and compared using a thermal analyzer and a tube furnace reactor. Results showed that the pyrolysis process of MA and MR can be divided into three stages, which corresponded to the volatile of free water, the decomposition of organic compounds and the stabilization of residues, respectively. Due to the removal of lipids after MA extraction, only one weight loss peak was recorded in the second stage of MR. Using the methods of Friedman, FWO and Starink, the average activation energies of MA and MR were calculated as 204.72 and 178.51 kJ/mol, respectively. Pyrolysis oil, gas, and char products were obtained from both MA and MR pyrolysis. Main gas products from pyrolysis of MA and MR contained CO2, CO, H2 and CHs. Compared with MA pyrolysis, the relative contents of CHs were lower (

State-of-the-art techniques for image and video classification take a bottom-up approach where local features are aggregated into a global final representation. Existing frameworks (i.e., bag of words or Fisher vectors) are specifically designed to aggregate vector-valued features such as SIFT descriptors. In this article, we propose a technique to aggregate local descriptors in the form of covariance descriptors (CovDs) into a rich descriptor, which in essence benefit from the second-order statistics along the coding pipeline. The difficulty in aggregating CovDs arises from the fact that CovDs lie on the Riemannian manifold of symmetric positive definite (SPD) matrices. Therefore, the aggregating scheme must take advantage of metrics and the geometry of the SPD manifolds. In our proposal, we make use of the Stein divergence and Nyström method to embed the SPD manifold into a Hilbert space. We compare our proposal, dubbed CovLets, against state-of-the-art methods on several image and video classification problems including facial expression recognition and action recognition.