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High energy storage density with low-energy loss polymer films are essential for high-performance electric devices. To avoid the high-energy loss of utilizing nonlinear polymer materials, a sandwich nanostructure comprising a linear polymer poly(methyl methacrylate) (PMMA) matrix embedded with a high dielectric constant BaTiO3 (BT) interlayer and poly(vinylidene fluoride) (PVDF) binder was constructed using a solution casting strategy. This structural design takes advantage of each component in the composite. The good dispersion of BT particles in the binder, which was incorporated between PMMA, enabled a high dielectric constant and fewer defects. Additionally, the excellent film formation ability of the PVDF binder guarantees the uniform thickness and stable structure of the BT mid-layer, and good miscibility between PVDF and PMMA enhanced the interaction between each layer. Interestingly, since the dielectric constant of PVDF was between BT fillers and PMMA, a dielectric gradient distribution mitigated the local electric field concentration, as proven by the simulation results. Consequently, a low-loss linear PMMA composite film exhibited satisfying breakdown strength and excellent discharged energy density, which were 25% and 460% higher than those of pristine PMMA, respectively.

Nanocomposite polymer materials are commonly used in energy storage devices on account of the excellent dielectric performance. However, there is a long-standing contradiction between dielectric constant and breakdown strength of nanocomposite. In this study, polyurea (PUA) is designed to in situ modify BaTiO3 (BT) nanoparticles. Based on the excellent dispersity, favorable compatibility and outstanding insulating performance of BT@PUA particles, the P(VDF-CTFE)/BT@PUA nanocomposite exhibits enhanced breakdown strength and reliability. In addition, the introduction of BT@PUA enhanced the dielectric constant to 10.72 and 35% larger than that of pure P(VDF-CTFE). As a result, the energy density of BT@PUA composite reaches 8.94 J/cm3, which is 1.65 times than P(VDF-CTFE) (5.41 J/cm3) and 4.5 times than the commercial biaxially oriented polypropylenes. Meanwhile, the quantified simulation illustrates the necessity of extremely high breakdown strength of the shell. Experiment results and simulation reveal that coating PUA is a novel and effective way to enhance energy storage performance for polymer nanocomposites with a promising broad application prospect.

The collective excitation of ordered spins, known as spin waves or magnons, can in principle radiate by emitting travelling photons to an open system when decaying to the ground state. However, in contrast to the electric dipoles, magnetic dipoles contributed by magnons are more isolated from electromagnetic environment with negligible radiation in the vacuum, limiting their application in coherent communication by photons. Recently, strong interaction between cavity standing-wave photons and magnons has been reported, indicating the possible manipulation of magnon radiation via tailoring photon states. Here, with loading an yttrium iron garnet sphere in a one-dimensional circular waveguide cavity in the presence of both travelling and standing photon modes, we demonstrate an efficient photon emissions from magnon and a significant magnon radiative damping with radiation rate found to be proportional to the local density of states (LDOS) of photon. By modulating the LDOS including its magnitude and/or polarization, we can flexibly tune the photon emission and magnon radiative damping on demand. Our findings provide a general way in manipulating photon emission from magnon radiation for harnessing energy and angular momentum generation, transfer and storage modulated by magnon in the cavity and waveguide electrodynamics., Comment: 9+7 pages, 4+2 figures

The application prospects of dielectric materials such as polyvinylidene fluoride polymers in the field of energy storage have stimulated extensive research, and the performances are mainly affected by crystallization. However, most of them are focused on the influences of single-layer crystalline rather than macroscopic structures. In this study, a unique sandwich structure is proposed by combining layer-by-layer casting and multi-step thermal processing methods to control the macroscopic crystallization in each layer. Four heating temperatures were first set, and it was found that as the drying temperature increases, the films present different crystallization, which results in different dielectric performances. According to this feature, a sandwich structure was proposed for modification of macroscopic crystallization and the influences on energy storage performance were studied. After macroscopic modification of the crystallization, a low loss [Formula: see text], high energy density (7.12[Formula: see text]J/cc) with the highest charge-discharging efficiency was obtained, which presents the advantages of this methods, and the related mechanisms were discussed.

The current research on the characteristics of clay minerals in oil-sand reservoirs of China is still in its infancy. The burial depth of oil sands in the western slope of the Songliao basin is relatively shallow, and the reservoir contains clay minerals. Scanning electron microscope observations and X-ray diffraction analysis were used to test the chemical composition and characteristics of clay minerals. Comprehensive analysis and further research found that the clay mineral content of the oil-sand reservoir was relatively low and the clay minerals belonged to the illite–montmorillonite mixed-layer, composed of montmorillonite and illite, with occasional kaolinite, but no chlorite. The oil-bearing property of the oil-sand reservoir was consistent with the type of clay mineral found. The reservoir containing a mixed layer of illite–montmorillonite has a relatively good oil-bearing potential, and the oil content ranged from 3.80% to 16.17%.

High performance dielectric polymer materials are a key point for energy storage capacitors, especially film capacitors. In this paper, a sandwich-structured polymer film is constructed to achieve high energy density and high efficiency. High dielectric materials of poly(vinylidene fluoride-hexafluoropropylene) (P(VDF-HFP)) doped with barium titanate (BaTiO3) are used as the outer layer to achieve a high dielectric constant, and a boron nitride nanosheet (BNNS) layer is inserted between P(VDF-HFP)/BaTiO3 to obtain a high breakdown field strength of composite films. The results indicate that when the doping amount of the BaTiO3 nanoparticles reaches 10 wt% and the mass fraction of the BNNS layer is 0.75 wt%, a significant improvement of energy storage performance is obtained. The energy storage density of the P(VDF-HFP)/BaTiO3/BNNSs composite film can reach 8.37 J cm−3, which is higher than 6.65 J cm−3 of the pure P(VDF-HFP) film. Compared with the P(VDF-HFP) film doped with BaTiO3, significant improvement of the breakdown field strength (about 148.5%) is achieved and the energy storage density increases 235% accordingly, resulting from the inserted BNNSs layer blocking the growth of electrical branches and suppressing leakage current. This novel sandwich-structured film shows promising future applications for high performance dielectric capacitors.

Most parts of China suffer often from haze pollution, which has a huge impact on human health. Road traffic has made the largest contribution to the haze. Of all the kinds of vehicular systems, the diesel engine produces the most PM; therefore, to reduce haze pollution, it is necessary research methods to reduce the PM produced by diesel engines. HHO (Brown's gas, Rhode's gas and HRG) is formed from H2 (60.79%) and O2 (30.39%) as well as a small amount of water vapour and active substances, such as oxygen radicals (O) and hydroxyl radicals (OH), which have quite strong oxidizing properties in the engine process, stimulating the C–H chain reaction during the combustion period and accelerating the oxidation of HC, CO and PM emissions as a result. The influence of blending HHO with diesel on diesel engine emission characteristics is well-researched, based on an 186FA single-cylinder diesel engine. The HHO was combined with air in the intake pipe. The influence of HHO on the amount of CO, HC, NO and PM emissions was analysed by collecting data under various speeds and loads. Through MOUDI, particles of various diameters under the highest torque working conditions and declared working conditions were collected to analyse how HHO affected the particle mass distribution in different diameter ranges. The analysis showed that when the speed was stable, the quantities of CO, HC and PM created were decreased by adding HHO; in addition, HHO had the greatest effect on PM. As the load increased, the amount of CO, HC and smoke declined gradually, but the decline of NO was smaller comparatively. Moreover, after blending with HHO, the quantity of NO created increased by 9.52% when the diesel engine operated according to external characteristics, and the quantity of HC, CO and PM created decreased by 31.6%, 11.3% and 20.71%, respectively. Finally, the gross mass of the particles dropped 67.48% and 42.53% under the highest torque working conditions and declared working conditions, respectively, with the distribution of diameters moving to smaller sizes. Introducing HHO into diesel can effectively reduce the generation of PM, which plays a positive role in reducing haze pollution.

The application prospects of dielectric materials such as poly(vinylidene fluoride) (PVDF) based polymers in the field of energy storage have stimulated extensive research. In this study, the energy storage characteristics of poly(vinylidene fluoride-hexafluoropropylene) (P(VDF-HFP)) films crystallized from several solvents with different vapor pressure were investigated. The charge-discharge efficiency of the P (VDF-HFP) film crystallized from N, N-dimethylformamide (DMF) demonstrates an efficiency of 85% under an electric field of 1000 kV cm−1, which is 1.42 times of the film crystallized from dimethyl sulfoxide (DMSO). Meanwhile, the insulation resistivity of the film crystallized from DMF is also higher than other films, and the energy storage characteristics are optimal in this study. This work provides guidance for the preparation of PVDF-based polymer films using the solution method.

The Fulongquan Depression is a major production area for natural gas in the Songliao Basin. This study was based on geochemical analysis of source rocks. Our results indicate that the kerogen types are primarily type III. These rocks represent a source of gas in a highly mature stage. The basin was formed during two major events of tectonic subsidence and uplift between 144 and 95 Ma before present. These periods were followed by a stable sedimentary burial phase. In the Cretaceous fault period, processes of secondary hydrocarbon generation were present. Corresponding to the two major tectonic subsidence movements, there were two key hydrocarbon generation processes. Contingent on research on sedimentary facies, source rock thicknesses, and the distribution and intensity of hydrocarbon generation, the northern and southern parts of this depression represent favorable areas for the exploration and development of hydrocarbon extraction.

The sliding wear tests were performed under the atmospheric conditions at 400 °C for H13 steel. The effects of load on the wear mechanisms and delamination patterns were studied. A new delamination pattern was found to appear in the mild-severe transition region of the elevated-temperature wear. The delamination pattern could be proved by the belt-like debris and the corresponding wide ditches on worn surfaces. Under the loads of 50–100 N, mild oxidative wear prevailed with the characteristics of the plate-like oxide debris and low wear loss and its delamination was from inside oxides or the interface between the oxides and bulk metal. The wear rate increased with increasing load; the mild–severe wear transitions occurred under the loads of 100–200 N concomitant with more and more belt-like debris and wide ditches on worn surfaces. In this case, the wear loss would be mainly attributed to a special delamination from inside the bulk metal underneath the tribo-oxides with the formation of belt-like debris containing oxide and bulk metal. The delamination pattern was realized by the way that the ploughed furrows were first formed by the micro-cutting of oxide particles in the delaminated zone, whereby cracks initiate from the furrow wall and propagate parallel to worn surface to cause the delamination.

A new in situ Al–Zr–O–B system is exploited. The Al–Zr(CO3)2–KBF4 components are used to fabricate the particle reinforced aluminum matrix composites by the direct melt reaction method. The analytical results of XRD and SEM show that the in situ endogenetic particles are ZrAl3, ZrB2 and Al2O3, which are well distributed in the aluminum matrix. The sizes of reinforced particles are 0.5–2.5 μm. The results of mechanical properties of the composites show that the tensile strength and yield strength are improved with the increase of theoretical volume fraction of particles in matrix in the range of 0–12%, which are much superior to those of aluminum matrix. The best elongation of composites is 33% when the theoretical volume fraction is 3%. The fracture mechanism belongs to a ductile one. The wear resistance properties of the composites are much higher than that of aluminum matrix. The best abradability is got when the theoretical volume fraction of particles is 6%. The wear mechanism of the aluminum matrix is adhesive wear while the wear mechanism of (ZrAl3 + ZrB2 + Al2O3)p/Al composites is abrasive wear.

2-Deoxyglucose (2-DG; 10 mM) replacing glucose for ∼15 min regularly causes a very sustained enhancement of synaptic transmission in the CA1 hippocampal zone (2-DG-induced long-term potentiation, 2-DG-LTP). This LTP is prevented by dantrolene (10μM) or by the NMDA antagonist aminophosphonovalerate (APV; 50–100 μM); it is Ca-dependent [1, 2], and is not depressed by adenosine antagonists (DPCPX and 8-SPT), which prevent the initial block of EPSP caused by 2-DG, but is not observed if glucose is replaced by sucrose instead of 2-DG. To clarify the role of [Ca]i, in 2-DG-LTP, we monitored fluo-3 fluorescence inCA1 neurons, in submerged slices kept at 30°C. 2-DG applied as above consistently led to a rapid, but reversible rise in fluorescece. Isomodar sucrose (for 15–40 min) elicited smaller, but significant increases in fluorescence. Dantrolene and APV greatly reduced 2-DG's effect, but Ca-free medium did not abolish it. Paradoxically, it was fully suppressed by 8-SPT, but not at all by DPCPX. The discrepancies between the effects of sucrose and 8-SPT on the fluorescence changes and on 2-DG-LTP suggest that the observed increases in the postsynaptic [Ca] i are not essential for 2-DG-LTP. In further experiments, intracellular recordings showed that 2-DG applications consistently hyperpolarizeCA1 neurons, probably owing to adenosine-mediated activation of K+ conductance (which could be prevented by DPCPX or 8-SPT, but not by a KATP antagonist, glyburide). The 2-DG-LTP of EPSP was not suppressed by EGTA leakage from electrodes, in keeping with the above evidence that the [Ca] i changes needed for the induction of 2-DG-LTP are not those observed postsynaptically. In this respect, as well as in the absence of postsynaptic depolarization, 2-DG-LTP offers a marked contrast to more conventional forms of LTP.

Temporary block of glycolysis by 2-deoxy-D-glucose (2-DG) reversibly suppresses synaptic transmission in the CA1 region of hippocampal slices. Recovery of responses is followed by a sustained potentiation of field excitatory postsynaptic potentials (EPSPs) (2-DG-LTP). To investigate the mechanisms involved in this type of LTP, we studied the effects of 2-DG on membrane properties of CA1 neurons (in slices from SpraguenDawley rats), recorded with sharp intracellular electrodes containing 3 M KCl, as well as patch electrodes, filled mainly with 150 mM KMeSO4 and Hepes. The predominant change produced by 15- to 20-min applications of 2-DG (10 mM, replacing glucose) was hyperpolarization (n5.6 ± 1.1 mV for 18 intracellular recordings and n7.2 ± 0.80 mV for 17 whole-cell recordings) accompanied by a fall in resistance (n33 ± 2.5% for 14 intracellular recordings and n11.6 ± 7.1% for 15 whole-cell recordings). Virtually identical hyperpolarizations were recorded in the presence of 20 μM glyburide (n5.5 ± 1.5 mV, n = 6), but they were abolished by adenosine antagonists 8-(p-sulfophenyl)theophylline (8-SPT) and 8-cyclopentyl-3,7-dihydro-1,3-dipropyl-1H-purine-2,6- dione (DPCPX) (2.8 ± 1.6 and 4.0 ± 1.7 mV, respectively; n = 5 for both). It was concluded that the hyperpolarization is most likely caused by an increase in K + conductance, activated by a 2-DG-induced rise in adenosine release. After such applications of 2-DG, a sustained potentiation of EPSPs (similar to the 2-DG-LTP of field EPSPs) was evident in five neurons recorded with intracellular electrodes but not in any of nine whole-cell recordings, where it was replaced by sustained, LTD-like depression. We conclude that a factor essential for 2-DG-LTP induction is lost during whole-cell recording.

Human adrenomedullin (hADM) is a newly isolated peptide with hypotensive activity in normotensive rats. The objective of this study was to investigate the effect of hADM(13–52) on hypertensive animals. hADM(13–52) induced a dose-dependent decrease in the blood pressure of spontaneously hypertensive rats and renal hypertensive rats. This result suggests that hADM is a novel antihypertensive peptide. In isolated rat aortic arteries, hADM(13–52) produced nitric oxide dependent relaxation and inhibited endothelin 1 and angiotensin II release. These in vitro effects may represent the molecular mechanisms underlying the hypotensive action of hADM in vivo.Key words: human adrenomedullin, nitric oxide, endothelin 1, angiotensin II, hypertension.