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Organic-rich continental shale, widespread in the Sichuan Basin during the deposition of the Jurassic Dongyuemiao Member (J1d), is considered the next shale hydrocarbon exploration target in southern China. To identify a shale gas sweetspot and reduce exploration risk, it is of great significance to determine the organic matter (OM) enrichment mechanism of J1d shale. In this study, based on sedimentological characteristics and organic matter content, high-resolution major and trace elements were systematically analyzed to demonstrate terrigenous influx, paleoredox, paleosalinity, paleoproductivity, and paleoclimate. The 1st section interval of the J1d 1st submember is dominated by shallow lake subfacies, while the other intervals have the characteristic of semideep to deep lake subfacies. The 1st submember interval of J1d lacustrine shale is characterized by the warmest-humid paleoclimate, strongest weathering degree, highest terrigenous input, moderate paleoproductivity, and paleoredox condition. Within the Dongyuemiao 1st submember, the 4th section interval has the highest paleoproductivity and the most oxygen-deficient condition in bottom water. During the deposition period of the 2nd submember, the sedimentary environment turned to a cold-dry paleoclimate, weak weathering degree, low terrigenous input, low paleosalinity, and high paleoproductivity. Under the background of semideep and deep lake, the terrigenous OM input plays the most critical role in controlling OM enrichment. Moreover, the high primary productivity of lake surface water and the suboxic condition of lake bottom water contribute to the formation of relatively higher TOC lacustrine shale interval in the 4th section of 1st submember. [ABSTRACT FROM AUTHOR]

The centroid of Lie algebra is a basic concept and a necessary tool for studying the structure of Lie algebraic structure. The extended Heisenberg algebra is an important class of solvable Lie algebras. In any Lie algebra, the anti symmetry of Lie operations is an important property of Lie algebra. This article investigates the centroids and structures of 2 n + 2 dimensional extended Heisenberg algebras, where all invertible elements form a group and all elements form a ring. Then, its main research results are extended to infinite dimensional extended Heisenberg algebras. [ABSTRACT FROM AUTHOR]

We define a four-dimensional Lie algebra g in this paper and then prove that this Lie algebra is solvable but not nilpotent. Due to the fact that g is a Lie algebra, ∀ x , y ∈ g , [ x , y ] = − [ y , x ] , that is, the operation [ , ] has anti symmetry. Symmetry is a very important law, and antisymmetry is also a very important law. We studied the structure of Poisson algebras on g using the matrix method. We studied the necessary and sufficient conditions for the automorphism of this class of Lie algebras, and give the decomposition of its automorphism group by A u t (g) = G 3 G 1 G 2 G 3 G 4 G 7 G 8 G 5 , or A u t (g) = G 3 G 1 G 2 G 3 G 4 G 7 G 8 G 5 G 6 , or A u t (g) = G 3 G 1 G 2 G 3 G 4 G 7 G 8 G 5 G 3 , where G i is a commutative subgroup of A u t (g) . We give some subgroups of g's automorphism group and systematically studied the properties of these subgroups. [ABSTRACT FROM AUTHOR]

The selective fluorination of aramid fiber surface was reported by Fe 3+ coordination on the benzimidazole unit. After the coordination, both of the two parts in benzimidazole unit, benzene ring and imidazole ring, take priority in the reaction with the fluorine gas, while the reaction with the amide bond is restrained. In this way, selective fluorination on benzimidazole unit is achieved, with the surface polarity increasing and chain scission behavior suppressed simultaneously. What’s more, the increased surface polarity enables the improvement of the interfacial shear strength by 24%, compared with that in a traditional fluorination way. In all, the study offers an easy and effective strategy for the regulation and controlling of direct fluorination reaction, and it provides a guideline for further adjustment of the reaction mechanism to meet the requirement in other applications. [ABSTRACT FROM AUTHOR]

A mesoporous silica loaded with molybdenum phosphide nanoparticles (MoP@MSN) was synthesized using Pluronic F-127 as a hard template. Using the method of XRD and HRTEM, the crystallinity, the phase structure, and the morphologies of the MoP@MSN were investigated. The results showed that the MoP@MSN were composed of nanoflakes with approximately 100 nm. Through the linear sweep voltammetry (LSV), the Tafel slopes of 100 and 341 mV were yielded for MoP@MSN and pure MoP, respectively, meaning that the composite of MSN can significantly improve the conductivity of the products. Meanwhile, the mesoporous MoP@MSN presented excellent electrochemical activity and stability toward hydrogen evolution compared with those of bulk MoP nanoparticles, showing a promising prospect in hydrogen production. [ABSTRACT FROM AUTHOR]

• Aeolian particle trajectories are studied through wind-tunnel experiments. • A method is proposed for estimating wind-blown grain lift-off parameters. • Particle velocities at heights below 1 mm from the ground are estimated. • The probability distribution of near-bed lift-off grain velocities is bimodal, and not unimodal. • Rebound and splash particles contribute two distinct peaks to the lift-off velocity distribution. The probability distribution function (PDF) of the lift-off velocities of Aeolian (wind-blown) sand particles – i.e., the velocities with which the particles rebound or are ejected from the bed owing to a granular-bed collision – is an important parameter in models of sediment transport and dust emission. However, in order to reliably describe this distribution function, measurements of the individual particle trajectories near the sand bed during sediment transport are required. Such measurements are challenging due to the high particle concentration near the bed, which makes it difficult to track the dynamics of the particles involved in the lift-off process. Here we seek to overcome this difficulty by applying an experimental method for grain trajectory detection, which allows us to obtain a large number of near-bed lift-off particle trajectories during sand transport in a boundary layer wind tunnel. The PDFs of horizontal and vertical lift-off velocities all were found to display a bimodal distribution at a height smaller than 1 mm from the bed. The first and second maxima in the distribution curve of horizontal and vertical lift-off velocities occur at around 0.25 and 1.0 ms−1, and at 0 and 1.0 ms−1, respectively. Moreover, the first maximum is mainly associated with splashed particles, whereas the second peak is mainly caused by rebound particles. However, the lift-off velocities far from the bed follow a unimodal distribution, in agreement with previous experiments. Our results are providing, thus, unprecedented insights about near-bed transport processes over wind-blown soils, and have implication for modelling granular-bed interactions in Aeolian sand transport and geomorphodynamic models. [ABSTRACT FROM AUTHOR]

Abstract: Nd2SiO5 ceramics were synthesized and their microwave dielectric properties were investigated. The hexagonal Nd4Si3O12 second phase disappeared and the pure monoclinic Nd2SiO5 phase could be obtained when the molar ratio of Nd2O3/SiO2 was 1:1.05 at 1450°C. The relative density of Nd2SiO5 ceramics increased with increasing temperature. The Nd2SiO5 ceramics sintered at 1500°C exhibited microwave dielectric properties: a dielectric constant (ε r) of 7.94, a quality factor (Q × f) of 38 800GHz and a temperature coefficient of resonant frequency (τ f) of −53ppm/°C. High resonant frequency led to a low dielectric constant and low Q × f value. Nd2SiO5 ceramics have a wide sintering temperature region. They are promising candidate materials for microwave passive components. [Copyright &y& Elsevier]

The Sm2SiO5 ceramics were synthesized and their microwave dielectric properties were investigated. The pure monoclinic Sm2SiO5 phase could be obtained when the molar ratio of Sm2O3/SiO2 was 1:1.05 at 1350°C. A small amount of hexagonal Sm4(SiO4)3 second phase occurred as temperature increased. The relative density of Sm2SiO5 ceramics increased with increasing temperature. The Sm2SiO5 ceramics sintered at 1500°C exhibited microwave dielectric properties: a dielectric constant (εr) of 8.44, a quality factor ( Q × f) of 64 000 GHz, and a temperature coefficient of resonant frequency (τf) of −37 ppm/°C. The Sm2SiO5 ceramics have a wide sintering temperature region and small negative τf values. They are promising candidate materials for millimeter-wave devices. [ABSTRACT FROM AUTHOR]

Continental shale in China is a key exploration target with regard to unconventional hydrocarbons. Systematic research on the mineral composition, organic geochemistry, and hydrocarbon mobility has been performed in the Da'anzhai (J1dn) lacustrine shale oil reservoirs, clarifying the factors controlling shale oil accumulation. The results suggest that J1dn consists of three sub-members, with an organic-rich interval developed within the second sub-member. Three types of lithological associations have developed within the organic-rich interval: Type 1 represents the interbedding relationship between shale and shell limestone and Type 2 represents shale with intercalated limestone, followed by Type 3. The brittleness index of the J1dn continental organic-rich shale is relatively low. The porosity of the Da'anzhai lacustrine shale ranges between 0.5% and 10.5% (average value of 5.89%). The porosity is predominantly due to inorganic pores, with a small amount being attributable to nanoscale microfractures and organic pores. The average porosity of the shell limestone is only 1.2%, but fractures at the micron and centimeter scales are well developed. The organic matter in the J1dn continental shale is mainly II1–II2, with maturity in the oil generation stage. The average oil saturation of the J1dn continental shale is 3.15%, with most samples having oil saturation of less than 4%. The J1dn continental shale has great exploration potential with regard to shale oil. Type 1 shale oil is affected by multiscale fractures, including bedding fractures, and has the best mobility. The high hydrocarbon generation capacity of lacustrine shale, coupled with the multiscale fractures within shell limestone and shale, is the principal controlling factor for hydrocarbon enrichment. Based on exploration practices, the Type 1 shale association may represent the optimal interval for future shale oil exploration in the Da'anzhai Member. [ABSTRACT FROM AUTHOR]

The weak interfacial adhesion of aramid fiber with resin matrix is believed as a major limitation for its wide application. In this study, a nondestructive grafting method was applied for surface modification of benzimidazole-contained aramid fiber. Using the NH in benzimidazole unit as active sites, aramid fiber surface was firstly decorated with densely SiO 2 structure, and a rough surface was obtained. Then, high density of NH 2 and C=C groups were introduced on fiber surface by the reaction with silane coupling agents. These functionalized NH 2 /C=C groups endow the fiber with the ability to chemically bonding with resin in a wide polarity range, including rubber, bismaleimide and epoxy resin. Also, the SiO 2 -decorated rough surface improves the level of mechanical interlocking with them. Experimental results show that the interfacial shear strength of functionalized fiber with natural rubber, bismaleimide and epoxy resin correspondingly increases 117%, 166% and 43%, compared with that of untreated fibers. Meanwhile, the grafting method is confirmed as nondestructive, and the superior mechanical property of aramid fiber is preserved. In all, the study presents a new effective method for the preparation of aramid fiber with excellent interfacial properties suitable for resin composite in a wide polarity range. [ABSTRACT FROM AUTHOR]

A solution-based “hot-injection” approach was developed to synthesize amorphous carbon-decorated and graphene-anchored hollow Co 9 S 8 nanoparticles as anode material for Li ion battery application. Such a rationally designed dually-protected structure could effectively accommodate the volume expansion of Co 9 S 8 nanoparticles during Li-cycling. As a result, as-synthesized nanocomposites could be successfully operated under ultrawide temperature window of −20 °C–70 °C, rendering excellent electrochemical performances, i.e., remarkable reversible capacities of 910 mA h g −1 after 100 cycles (at 500 mA g −1 ) and 622 mA h g −1 after 200 cycles (at 1000 mA g −1 ) at 70 °C. These attributes enable three-dimensional structured Co 9 S 8 nanoparticles to be promising anode materials of advanced Li-ion batteries for large-power applications such as electric vehicles under extreme temperature environments. [ABSTRACT FROM AUTHOR]

Reduced graphene oxide (rGO)-encapsulated MnGeO 3 microspheres have been yielded via a facile, scalable and environmentally friendly route. Hydrothermal method was utilized to recrystallize MnGeO 3 particles and form rGO encapsulation. Such rationally designed rGO-encapsulated MnGeO 3 microspheres afforded excellent electrochemical performances, i.e. high first discharge capacity of 1364 mAh g −1 and charge capacity of 810.8 mAh g −1 , and reversible capacity of 624.6 mAh g −1 after 50 cycles at a current density of 200 mA g −1 when they were employed as anode materials for Li ion batteries. These advantageous attributes make rGO-encapsulated MnGeO 3 microspheres the potential anode materials for Li-ion batteries. [ABSTRACT FROM AUTHOR]

Abstract: SnO2-doped CaSiO3 ceramics were successfully synthesized by a solid-state method. Effects of different SnO2 additions on the sintering behavior, microstructure and dielectric properties of Ca(Sn1−x Si x )O3 (x=0.5–1.0) ceramics have been investigated. SnO2 improved the densification process and expanded the sintering temperature range effectively. Moreover, Sn4+ substituting for Si4+ sites leads to the emergence of Ca3SnSi2O9 phase, which has a positive effect on the dielectric properties of CaO–SiO2–SnO2 materials, especially the Qf value. The Ca(Sn0.1Si0.9)O3 ceramics sintered at 1375°C possessed good microwave dielectric properties: ε r =7.92, Qf =58,000GHz and τ f =−42ppm/°C. The Ca(Sn0.4Si0.6)O3 ceramics sintered at 1450°C also exhibited good microwave dielectric properties of ε r=9.27, Qf=63,000GHz, and τ f =−52ppm/°C. Thus, they are promising candidate materials for millimeter-wave devices. [Copyright &y& Elsevier]

A facile hydrothermal approach has been successfully adopted to synthesize two‐dimensional Nb2CTx MXene, targeting sodium storage approach in two‐dimensional MXene. As an anode material for sodium‐ion batteries (SIBs), as‐prepared Nb2CTx MXene delivered a stable electrochemical performance of ∼102 mA h g−1 after 500 cycles at a current density of 1.0 A g−1. Further, the full cell comprising of Na3V2(PO4)3@C cathode and Nb2CTx MXene anode also rendered a reversible capacity of 181 mA h g−1 at a current density of 100 mA g−1 after 50 cycles. The good sodium storage could be ascribed to the contribution of hybrid pseudocapacitance, effectively promoted charge storage, unique layered structure and expedited dynamic diffusion of ions. Accordingly, these facts enabled the Nb2CTx MXene to be a promising candidate as an anode material for sodium‐ion batteries. [ABSTRACT FROM AUTHOR]

Optogenetics is an innovative method for precise control of biological function, which makes light manipulation displays more advantages than electric energy because of contactless spatial flexibility and cell-to-cell synchronous communication. The aim of this study was to perform different illumination modes with blue laser to investigate optical control of the mice hearts. In this study, we transfected the light sensitive protein ChR2(H134R) into mouse hearts, which were illuminated with a 473 nm laser on the Langendorff apparatus. We recorded all the signals of electrograms (EGs), epicardium monophasic action potential (MAPs) and light output signals to analyze myocardial electrical activity. EGs and MAP showed that ChR2 expression in the heart can be flexibly controlled by blue light across different illumination sites with corresponding triggered ectopic rhythm. Illumination intensity, pulse duration, and impulse frequency were associated with the light capture rate. Continuous illumination with the threshold intensity on the left ventricle had little influence on sinus rhythm and ventricular electrophysiology. Our results support that flexible control of the cardiac rhythm with optogenetics provides an innovative approach to cardiac research and therapy. • Heart expressed ChR2 can be controlled by blue light. • Light pulses initiated different ectopic rhythm with different illumination sites. • The constant illumination in threshold intensity was safe. • Different mode of light control can be used in cardiac research and therapy. [ABSTRACT FROM AUTHOR]

Hydrothermal mineral assemblages and related hydrothermally enhanced fracturing are common in the Precambrian Dengying Formation of Central Sichuan Basin. Petrographic and geochemical analyses of core samples show that the hydrothermal dolomite reservoirs of Dengying Formation consist of four main types of pores in the reservoir facies. These include: 1) hydrothermal dissolution vug (or pore), 2) intercrystalline pore, 3) residual inter‐breccia vug (or pore), and 4) enlarged dissolved‐fracture. There are three different fabrics dolomite in hydrothermal dolomite reservoirs, namely, saddle dolomite, fine‐medium dolomite and micritic dolomite. Micritic dolomite is the original lithology of host rock. Saddle dolomite with curved or irregular crystal faces was directly crystallized from hydrothermal fluids (average temperature 192°C). Fine‐medium dolomites are the products of recrystallization of micritic dolomite, resulting in abnormal geochemical characteristics, such as slight depletion of δ18O, significant enrichment of Mn‐Fe and 87Sr/86Sr, and positive Eu anomaly. A model for the distribution of various hydrothermal dolomite reservoir facies is proposed here, which incorporates three fundamental geological controls: 1) extensional tectonics and tectono‐hydrothermal events (i.e., the Xingkai Taphrogenesis of Late Sinian‐Early Cambrian, and Emei Taphrogenesis of Late Permian), 2) hydrothermal fluid storage in clastic rocks with large thickness (e.g., Nanhua System of Chengjiang Formation and part of Doushantuo Formation), and 3) confining bed for hydrothermal fluids (such as, the shale in Qiongzhusi Formation). The supply of hydrothermal fluid is critical. Large basement‐rooted faults and associated grid‐like fracture system may function as the channels for upward migration of hydrothermal fluid flow. The intersection of the above‐mentioned faults (including the conversion fault), especially transtensional sags above negative flower structures on wrench faults can serve as a key target for future hydrocarbon exploration. [ABSTRACT FROM AUTHOR]

The poor Uv stability and weak interfacial adhesion are considered as the bottleneck problems for further application of aramid fiber. Herein, a new strategy, Fe 3+ coordination, was reported for aramid fiber to simultaneous improve its Uv resistance and composite interfacial shear strength. Fe 3+ was introduced onto aramid fiber by coordinating with benzimidazole unit of fiber structure. It can reach a doping capacity of as high as 1516ug/g fiber, and the fiber surface is saturatedly covered with Fe 3+ . The chemical structure of Fe 3+ -benzimidazole brings about strong metal-enhanced fluorescence emission effect, which, in turn, greatly raises its Uv stability. Owing to the Fe 3+ coordination, the tensile strength of Fe-coordinated fiber could preserve as high as 96% after Uv irradiation, compared with 73% of untreated fiber. Meanwhile, the introduction of Fe 3+ improves the surface polarity of aramid fiber and consequently leads to the increase of the composite interfacial shear strength by 39%. It is believed that the Fe-coordinated fiber integrates the advantages of easy production, cost-effective and increased Uv stability, as well as high composite interfacial adhesion, and can be used as promising enhancement for the advanced composite material in harsh environment. [ABSTRACT FROM AUTHOR]

Graphene-covered and carbon-encapsulated CoSO 4 nanoparticles (a-C@CoSO 4 @GNs) were first prepared by a facile solution-phase route followed by heat treatment. Subsequently, a-C@CoSO 4 @GNs nanoparticles were utilized as anode materials of Li ion batteries. Such a rationally designed three-dimensional nanostructure could effectively accommodate the volume expansion of CoSO 4 particles during Li-cycling. As a consequence, a-C@CoSO 4 @GNs have delivered remarkable electrochemical performances, i.e., high first discharge capacity (994 mA h g −1 ), prominent cyclic performance of 662.7 mA h g −1 at a current density of 200 mA g −1 and excellent large-current capacity of 497 mA h g −1 at a current density of 1.5 A g −1 after 50 cycles due to catalytically reduced mechanism. More importantly, a-C@CoSO 4 @GNs electrodes possessed outstanding low/high temperature properties, i.e., reversible capacity of 130 mA h g −1 at −20 °C and 1362 mA h g −1 at 60 °C at a current density of 200 mA g −1 . These advantageous attributes make inexpensive, easily available, widespread and non-toxic CoSO 4 promising candidate as anode materials for high-performance lithium-ion batteries under extremely operational environments. [ABSTRACT FROM AUTHOR]

Abstract: The aim of this study is to observe the synergistically enhanced percutaneous penetration and skin analgesia of tetracaine gel containing menthol and ethanol through experimental and clinical studies. Four anesthetic gels containing 4% tetracaine in carbomer vehicle named T-gel (containing no menthol or ethanol), 5%M/T-gel (containing 5% menthol), 70%E/T-gel (containing 70% ethanol, an optimal concentration for antiseptic), and 5%M+70%E/T-gel (containing both 5% menthol and 70% ethanol), respectively, were fabricated. The in vitro mouse skin permeation was investigated using a Franz diffusion cell. The mouse skin morphology was examined by a scanning electron microscope. The in vivo skin analgesic effect in mice was evaluated using the von Frey tests. To determine the efficacy of tetracaine gels for managing the pain in human volunteers, a paralleled, double-blinded, placebo-controlled, randomized controlled trial design combined with verbal pain scores (VPS) was performed. The combination of menthol and ethanol (5%M+70%E/T-gel) conferred significantly higher tetracaine diffusion across full-thickness mouse skin than 5%M/T-gel, 70%E/T-gel, and T-gel. The ultra structure changes of mouse skin stratum corneum treated with 5%M+70%E/T-gel were more marked compared with those of any other tetracaine gel. von Frey tests in mice showed a synergistically enhanced effect of menthol and ethanol on the analgesia of tetracaine gel. The mean VPS were significantly lower for volunteers treated with 5%M+70%E/T-gel than those receiving other gels or the EMLA cream. 5%M+70%E/T-gel possessed the shortest anesthesia onset time, the longest anesthesia duration and the strongest anesthesia efficacy. Seventy percent ethanol in 5%M+70%E/T-gel not only improved the analgesic efficacy of the tetracaine gel through synergistically enhanced percutaneous permeation with menthol but also served as an antiseptic agent keeping drug application site from infection. 5%M+70%E/T-gel is a potential topical anesthesia preparation for clinical use. [Copyright &y& Elsevier]

Introduction: Optogenetics is an innovative approach combined with genetic encoding of light sensitive proteins and optical manipulation techniques, which provide a cell-specific, high spatial-temporal, flexible and pain-free resolution for cardiac modulation. Hypothesis: Optogenetics enables optoelectronic conversion which can exhibit diversity modulation of the cardiac rhythm according to the illumination alterations. Methods: Adeno-associated virus (AAV) vectors encoding Channelrhodopsin-2 (ChR2) (AAV9-CAG-hChR2 (H134R)-mCherry) were injected into the rat jugular vein to derive ChR2 expression in the whole heart (n=5). Eight weeks later pulse illumination generated by a 473nm laser was focused on different sites of the heart in a 2mm diameter circle to evoke optical pacing of 1:1 capture. After that ventricular fibrillation was induced by coronary artery ligation and burst stimulation in vivo and continuous illumination of 1 second in 2 times of threshold intensity was located on the infarct area, right ventricle and apex 5 seconds after induced arrhythmia to observe the termination efficacy respectively. Results: Pulse illumination on the right atrium, left and right ventricle, septum and apex succeeded in 1:1 pacing (Figure 1A and 1B). The light capture rate detected on the right ventricular illumination raised with the light intensity and pulse duration as presented in the curve (Figure 1C and 1D). The induced ventricular arrhythmia was terminated as the light continuously illuminated on the infarct zone, right ventricle and apex. The successful termination rate was calculated to be 100% in apex and lower in the other two sites (Figure 1E and 1F). Conclusions: These in vivo evidence suggested that epicardial light irradiation on the ChR2 expression heart achieved different cardiac manipulations according to the different illumination pattern. Optogenetic pacing and defibrillation could provide an alternative strategy for arrhythmia therapy. [ABSTRACT FROM AUTHOR]