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CFNCs with a high-curvature 3D hollow structure and rich interfaces enable activation of –CF and –CF2 groups, which results in cathode capacity of 1056 mAh g−1 and energy density up to 2487 Wh kg−1 beyond the theoretical limits of the Li-CFx system.

2D metal thiophosphate SnP2S6 was discovered as a new dielectric layer with a high dielectric constant (≈23), realizing a low subthreshold slope down to 69.4 mV dec−1 in the field effect transistor device geometry.

A novel complex [PtAg(dppm)2(CCC6H4COOCH3-4)2Cl] with two crystal morphologies as rod-like and prism was separately obtained by manipulating the recrystallization solvents. They exhibit glamorous morphology-dependent photoluminescence.

Poor high-temperature stability (HTS) and weak microwave absorption performance (MAP) are a major restriction for wave-absorbing materials in elevated temperature ambient. Consequently, the Stöber process and the sol–gel method are first devised and used to create multi-core/shell SiO2@Al2O3 nanostructures (MCSNs) on Ti3AlC2 (TAC). The MCSNs with a thickness of 135–215 nm raise the starting oxidation temperature of the matrix by 400°C. Furthermore, the weight gain drops from 17.44 to 2.32% within 1 h at 800°C. The effective absorption bandwidth with a reflection loss (RL) ≤ −10 dB of the MCSNs-coated TAC is 3.25 GHz (8.68–11.27 and 11.63–12.29 GHz) at a thickness of 2.0 mm, which is 4.7 times that of the matrix. The minimum RL is reduced by a factor of 2.77 from −10.68 to −29.55 dB. The enhanced MAP is due to the introduced multiple reflection events and scattering mechanism as well as the enhanced electronic polarization, interface polarization, and polarization relaxation. The growth of the MCSNs provides a reference for the design and preparation of bifunctional materials with good HTS and MAP.

Ductal carcinoma in situ (DCIS) is considered a non-invasive precursor to breast cancer, and although associated with an increased risk of developing invasive disease, many women with DCIS will never progress beyond their in situ diagnosis. The path from normal duct to invasive ductal carcinoma (IDC) is not well understood, and efforts to do so are hampered by the substantial heterogeneity that exists between patients, and even within patients. Here we show gene expression analysis from > 2,000 individually micro-dissected ductal lesions representing 145 patients. Combining all samples into one continuous trajectory we show there is a progressive loss in basal layer integrity heading towards IDC, coupled with two epithelial to mesenchymal transitions, one early and a second coinciding with the convergence of DCIS and IDC expression profiles. We identify early processes and potential biomarkers, including CAMK2N1, MNX1, ADCY5, HOXC11 and ANKRD22, whose reduced expression is associated with the progression of DCIS to invasive breast cancer.

ZrB2 is widely used in refractory linings and electrodes as well as in a range of applications including microelectronics and cutting tools, owing to its excellent characteristics, such as high hardness, high melting point, high strength, high thermal conductivity, and good thermal shock resistance. However, ZrB2 readily oxidizes, especially at high temperatures, which is ascribed to the reaction between ZrB2 and O2 in air. This study shows that a structural self-deterioration phenomenon occurs in ZrB2, even in vacuum or inert atmosphere. ZrB2 exhibits a characteristic, irreversible increase in resistivity in a high vacuum–high temperature environment. During repeated variable temperature resistivity testing, the resistivity of ZrB2 increases by 3.28% in the first cycle and 0.61% in the second. To investigate further, in-situ TEM showed that ZrB2 experiences an unusual phase transition reaction at high temperatures, even under a high vacuum environment. Oxidation results in a large number of disordered, layered structures and holes inside the ZrB2 particles. This microstructure evolution mechanism decreases the electrical conductivity and affects the performance of ZrB2. The study demonstrates the need to thoroughly investigate the microstructure changes in ZrB2 at high temperatures, under an inert atmosphere or high vacuum, and to widen the investigations to other properties beyond electrical resistivity.

The hydrogen evolution reaction (HER) is an emerging renewable energy source to derive clean, efficient, and high-energy-density hydrogen fuel from electrochemical water splitting mostly by using t...

Traditional fluorinated carbon (CFx) batteries are greatly limited in their applications mostly because of inferior rate performances, initial voltage delay and low fluorine-to-carbon ratio below one. This work innovatively applies graphite nanosheets (NSs) as carbon source and optimizes the fluorination process at temperature range of 250–400 °C to prepare CFx NSs. Specifically, the edge defects and –CF2, –CF3 perfluorinated functional group active sites are introduced into NSs in the form of covalent/semi-covalent/semi-ionic bonds by adjusting the temperature which also breaks the limit of fluorocarbon ratio to achieve ultra-thin microstructure with high performances. In the battery assembly process, a series of discharge electrolytes are introduced to improve the quality and realize the ultrahigh specific capacity. The optimized CFx-400 °C NSs deliver an excellent specific capacity of 921 mAh·g−1 at a current density of 10 mA·g−1 with a high energy density value of 2210 Wh·kg−1. Moreover, the new electrolytes are selected which not only serve as electrolytes but also can be loaded on CFx surface for various discharge reactions without affecting the actual battery function. Thus, the lightweight tabs and current collectors are selected to control the loading of active material and injection coefficient. The presented battery design strategy provides a new strategy to achieve an ultrahigh specific energy density of 1116 Wh·kg−1.

Most of the magnetic microwave absorbers are ineffective in extreme corrosive environments of acids and alkalis which abruptly reduce their performance. Therefore, it is urgent and worthwhile to produce the bifunctional materials with excellent corrosion resistance and microwave absorption property. This work presents the in-situ growth of double shells of silica and carbon on FeSiAl (FSA) alloy surface to obtain an integrated FSA@SiO2@C hybrid structure via combined Stober and catalytic chemical vapor deposition (CCVD) techniques. The hybrid structure acquires the strengthened bi-functional for anti-corrosion and microwave absorption due to the excellent corrosion shielding protection and well dielectric properties of SiO2 and carbon hybrid structure. Importantly, the hybrid morphology retains excellent stability of more than 150 h in 5.0 wt% NaCl acid solution. Moreover, FSA@SiO2@C hybrid possesses enhanced microwave absorption performance with a minimum reflection loss (RLmin) of −46.75 dB at 5.74 GHz with a matching thickness of 3.5 mm, and the effective bandwidth (RL

The sensitivity of ethanol sensor is of paramount importance in a variety of areas, including chemical production with ethanol, alcohol testing for driving safety, etc. Herein, α-Fe2O3 nano-cylinders with atomic carbon layers are synthesized, for the first time, through in-situ catalytic chemical vapor deposition combined with hydrothermal techniques for the detection of ethanol. The reported α-Fe2O3@C nano-cylinders with double surficial strain effects deliver an ethanol detection sensitivity of ～8 times as compared with α-Fe2O3 nano-cylinders, ∼10 times higher as compared with its detection sensitivity to ammonia, para-xylene, methanol and benzene. The sensor also exhibits over-14-day operation stability and the minimum detection limit of 10 ppm. To our best knowledge, the performances surpass those of previously reported α-Fe2O3. Such attractive performances are attributed to the enhanced charge transfer in α-Fe2O3 owing to the double surficial strain effects of α-Fe2O3@C nano-cylinders and the efficient adsorption of ethanol with atomic carbon layers.

In order to study the occurrence mechanism of rock burst in L-shaped zone during a fully mechanized mining period, the No. 705 working face which is located in Baojishan Colliery is taken as a typical engineering background. By means of in situ investigation, theoretical analysis, numerical simulation, in situ tests, and relevant monitoring methods, the occurrence mechanism of rock burst and corresponding prevention technology are studied. The results show that a coal pillar with some confining pressure in the L-shaped zone is established by FLAC3D numerical simulation software, and the numerical simulation results indicate that the change in static load has a greater effect than dynamic load on coal pillar unstable failure; the static load plays a role in storing energy, and dynamic load plays a role in inducing rock burst; the bolt-mesh-cable support and high-pressure water jet unloading combined technology is put forward to prevent rock burst in roadways, and the numerical simulation results show that stress distribution of surrounding rock meets the model of strong-soft-strong (3S) structure, and the moment distribution is reasonable. In the follow-up mining, a limit value of coal fines is used to determine that this measure is a reasonable method to prevent rock burst. The study conclusions provide theoretical foundation and new guidance for preventing rock burst by synergistic effect technology in roadways.

Chemical stability of phosphors is critical to the efficiency and lifetime of the white light-emitting diodes. Therefore, many strategies have been adopted to improve the stability of phosphors. However, it is still lack of report on the improvement of thermal stability and hydrolysis resistance of phosphors by a single layer coating. Due to the high transmittance and high chemical inertness of graphene, it was coated on the surface of Sr2Si5N8:Eu2+ phosphor by chemical vapor deposition, aiming to improve its thermal stability and hydrolysis resistance. The chemical composition and microstructure of the coating were characterized and analyzed. A nanoscale carbon layer was attached on the surface of Sr2Si5N8:Eu2+ phosphor particles in an amorphous state. In coated Sr2Si5N8:Eu2+ phosphor, the oxidation degree of Eu2+ to Eu3+ was significantly suppressed. At the same time, the surface of Sr2Si5N8:Eu2+ particle turned from hydrophilic to hydrophobic after carbon coating, and consequently the hydrolysis resistance of Sr2Si5N8:Eu2+ phosphor was greatly improved. After tests at 85 °C and 85% humidity for 200 h, the carbon coated Sr2Si5N8:Eu2+ phosphor still maintained about 95% of its initial luminous intensity as compared with 35% of the uncoated. By observing the in-situ microstructure evolution of coated phosphor in air-water vapor environment, remained presence of the carbon layer even at 500 °C explained the excellent chemical stability of carbon coated Sr2Si5N8:Eu2+ phosphor in complex environment. These results indicate that a nanoscale carbon layer can be used to provide superior thermal stability and hydrolysis resistance of (oxy) nitrides phosphors.

Robust neuromorphic computing in the Big Data era calls for long-term stable crossbar-array memory cells; however, the elemental segregation in the switch unit and memory unit that inevitably occurs upon cycling breaks the compositional and structural stability, making the whole memory cell a failure. Searching for a novel material without segregation that can be used for both switch and memory units is the major concern to fabricate robust and reliable nonvolatile cross-array memory cells. Tellurium (Te) is found recently to be the only peculiar material without segregation for switching, but the memory function has not been demonstrated yet. Herein, apparent piezoelectricity is experimentally confirmed with spontaneous polarization behaviors in elementary 2D Te, even in monolayer tellurene (0.4 nm), due to the highly oriented polarization of the molecular structure and the non-centrosymmetric lattice structure. A large memory window of 7000, a low working voltage of 2 V, and high on switching current up to 36.6 µA µm

The helical structures possess unique physical and chemical properties, such as superelasticity, high specific strength, chirality, and electromagnetic cross-polarization characteristics. With the development of nanoscience and nanotechnology, helical structures with various scales have been discovered or synthesized artificially. Among them, the helical carbon materials receive much attention around the world. Herein, we present a brief review of the development of helical carbon materials in terms of structures, synthesis techniques and mechanisms, and applications. The controllable designing of catalysts, carbon sources and reaction parameters plays a key role to optimize the properties of the helical carbon materials. At the same time, the applications in microwave absorption devices, sensors, catalysts, energy conversions and storage devices, and solar cell are also presented. For the good chemical and physical properties, helical carbon materials have a good application prospect in many fields. The potential issues and future opportunities of the helical carbon materials are also proposed.

To develop and validate a mathematical model for predicting intracranial pressure (ICP) noninvasively using phase-contrast cine MRI (PC-MRI). We performed a retrospective analysis of PC-MRI from patients with communicating hydrocephalus (n = 138). The patients were recruited from Shenzhen Second People’s Hospital between November 2017 and April 2020, and randomly allocated into training (n = 97) and independent validation (n = 41) groups. All participants underwent lumbar puncture and PC-MRI in order to evaluate ICP and cerebrospinal fluid (CSF) parameters (i.e., aqueduct diameter and flow velocity), respectively. A novel ICP-predicting model was then developed based on the nonlinear relationships between the CSF parameters, using the Levenberg–Marquardt and general global optimisation methods. There was no significant difference in baseline demographic characteristics between the training and independent validation groups. The accuracy of the model for predicting ICP was 0.899 in the training cohort (n = 97) and 0.861 in the independent validation cohort (n = 41). We obtained an ICP-predicting model that showed excellent performance in the noninvasive diagnosis of clinically significant communicating hydrocephalus.

Low infrared emissivity in 3–5 μm or 8–14 μm band has been realized in different host materials. Realizing the low infrared emissivity in single material covering the entire band is rarely achieved. This research explores a binary system of ultra-high temperature ceramic ZrB2–CeO2 composites prepared by solid state sintering. their phase composition, microstructure evolution, reaction mechanism and infrared emissivity performance were discussed in detail. It was found that CeO2, ZrB2, ZrO2, and ZrnCe1-nO2 existed in the sample in addition to the coated glass phase of CeO2 on the surface of the sample. In-situ HRTEM results clearly revealed a series of reaction mechanism of CeO2 and ZrB2. With the increase of sintering temperature, the CeO2 particles gradually transformed into a glass phase, and were distributed on the surface of ZrB2 particles, and ZrO2 was formed on the surface of ZrB2, simultaneously. Consequently, ZrnCe1-nO2 is formed as the reaction of ZrO2 and CeO2. Compared with the infrared emissivity spectra of pure CeO2 and ZrB2, a low infrared emissivity less than 0.2 in a wider coverage band of 3–5 and 8–14 μm in ZrB2–CeO2 compounds was achieved as a result of synergistic interaction between CeO2 and ZrB2. The obtained information about the phase composition and microstructure evolution helps to realize low infrared emissivity in a wider coverage band in compounds via composition and microstructure modification.

K2SiF6:Mn4+ phosphor is well known for its excellent red emission performance which is vital for improving the color rendering of white light-emitting diodes. However, the poor moisture resistance limits its application in optical devices. In this paper, K2SiF6:Mn4+ phosphor is coated with an inorganic hydrophobic protective layer to obtain good moisture resistance. Chemical vapor deposition method was used to decompose acetylene at high temperature, and the generated nanoscale carbon layer worked as a hydrophobic protective coating on the surface of the phosphor. Microstructure, compositions and properties of the synthesized K2SiF6:Mn4+@C phosphor were investigated in detail. It is found that most of the deposited carbon is coated on the surface of phosphor crystals in amorphous state. The carbon atoms are bonded with the fluorine element in K2SiF6:Mn4+ phosphor, forming carbon-fluorine (C–F) covalent bonds. The moisture resistance of K2SiF6:Mn4+@C phosphor is improved owing to the protection of the hydrophobic carbon. The relative emission intensity of K2SiF6:Mn4+@C phosphor could maintain 73% of the initial luminous intensity after immersing in the aqueous solution at room temperature for 8 h, whereas K2SiF6:Mn4+ phosphor without carbon coating was only 0.7% remaining of the initial value under the same conditions.

Hydrogen production from direct water electrolysis has long been pursued as a key that may revolutionize the hydrogen economy. With the rapid availability of electricity generated using renewable energy resources, this long-pursued target is now closer to reality than ever before. To date, most studies regarding electrocatalytic hydrogen evolution reaction (HER) are carried out in strong acidic/alkali electrolytes. However, hydrogen production from HER under extreme pH conditions has several drawbacks, including a corrosive working environment, the requirement of expensive anion/cation exchange membranes, and acidic/alkali withstanding electrocatalysts. The more sustainable approach to address these drawbacks is to deploy neutral/near-neutral electrolytes for HER. Regretfully, both theoretical discussions and practical applications regarding HER under neutral/near-neutral conditions are relatively rare and very elusive. In this review, we systematically discuss the current understandings of HER mechanisms under neutral conditions and analyze the influences of different types of neutral electrolytes. The most recent advances in the development of neutral HER electrocatalysts are summarized and exemplified, and general electrocatalyst design principles are highlighted. Lastly, we provide our perspective on the potential future research direction. We hope that this review inspires future endeavors to realize efficient HER for hydrogen production under neutral conditions.

Bifunctional catalysts for water-electrolysis are developed to simplify electrode- and cell-manufacturing. Hitherto, screening bifunction catalysts relies on experimental trials of high-performance cells and theoretical calculations of free-energy changes in the HER/OER intermediate steps, with high costs and constraints. Herein, we derive from the inevitable electrode-surface oxidation in water electrolysis and the semiconductor physics of such an oxidized electrode surface a band-diagram perspective: the oxidized electrode surface governing the catalytic activities in a bifunctional water-electrolysis cell should be a semiconductor with an effective bandgap not much larger than the HER-OER electrochemical potential gap of 1.23 eV. This perspective and its applications are elaborated with a set of experimental and DFT-computational results with FeP as a nominal bifunctional catalyst on nickel electrodes for the construction of a high-performance cell exhibiting 10 mA cm−2 at 1.40 V. The proposed “bandgap screening” is easy, low-cost, and applicable for expediting the development of new bifunctional catalysts.

The large size of sodium ions (Na+) restricts the choice of electrode materials; therefore, to realize low-cost energy storage systems, exceptional electrodes are required. Here, we have overcome this bottleneck by developing porous quasi-graphitic carbon (PGC) sheets at the surface of water-soluble KCl crystals as a green catalyst. The KCl crystals not only avoid the use of hazardous chemicals but also provide easy manipulation of the structural and surface chemistry of PGC sheets on a large-scale. The as-synthesized PGC sheets are enriched with micropores and amorphous reservoirs, which serve as mass transport channels and storage sites for Na+, respectively. Interestingly, when PGC sheets are employed as an anode in the sodium-ion battery, they showed an excellent reversible specific capacity of 237 mA h g−1 with outstanding cyclic stability by retaining 83.5% capacity after 250 cycles at 0.1 A g−1 at a capacity decay of 0.07% per cycle, while remaining stable up to 550 cycles when tested at 0.5 A g−1. Thus, the simple synthesis and large-scale production of PGC with high sodium storage capacity make it a potential candidate for secondary ion batteries.

Excessive activation of voltage-gated sodium channel Nav1.3 has been recently reported in secondary traumatic brain injury (TBI). However, the molecular mechanisms underlying regulating voltage-gated sodium channel (Nav1.3) has not been well understood. The present study used a TBI rat model induced by a fluid percussion device and performed a circRNA microarray (n=3) to profile the altered circRNAs in the hippocampus after TBI. After PCR validation, certain circRNA was selected to investigate the function and mechanism in regulating Nav1.3 in the TBI rat model by intracerebroventricular (ICV) injection with lentivirus. The neurological outcome was evaluated by Morris water maze (MWM) test, modified Neurological Severity Score (mNSS), brain water content measurement, hematoxylin, and eosin (H&E) staining. The related molecular mechanisms were explored with PCR, western blotting, luciferase reporter, chromatin immunoprecipitation (ChIP), and electrophoretic mobility shift assay (EMSA). A total of 347 circRNAs were observed to be differentially expressed (FC ≥1.2 and p < 0.05) after TBI, including 234 up-regulated and 113 down-regulated circRNAs. Among 10 validated circRNAs, we selected circRNA_009194 with the maximized up-regulated fold change (n=5, FC=4.45, p