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This article discusses the development of an improved and eco-friendly synthesis method for (R)-5,7-difluorochroman-4-ol, a key intermediate in the production of Tegoprazan, a medication used to treat acid-related diseases. The researchers optimized the reaction conditions and achieved a high yield and purity of the desired product using lipase-catalyzed resolution and Mitsunobu inversion. This method shows promise for practical use in the green synthesis of Tegoprazan due to its efficiency and environmental sustainability. The document provides a detailed account of the synthesis process and acknowledges financial support from the CQMU Program for Youth Innovation in Future Medicine. [Extracted from the article]

Industrial alumina was used as raw material in the high-temperature calcination process, and AlF 3 was introduced to promote mass transfer in the gas phase. The calcination environment, such as sealing, calcination temperature, and holding time, was analyzed to enhance the effect of AlF 3 to promote the crystal growth of alumina. Here, round-like flake α-Al 2 O 3 with an average particle size (D50) of about 18–38 μm were obtained at low dosages (0.1–0.4 wt%) of AlF 3. The morphology and particle size of α-Al 2 O 3 were further adjusted by introducing different types of micron-scaled nuclei as template inducers. Round-like flake and spherical-like large single crystals α-Al 2 O 3 with an average particle size greater than 35 μm were obtained, respectively, with 65 wt% of 15 μm flake and 10 μm bulk α-Al 2 O 3 nuclei added. In addition, the regulation mechanism of AlF 3 and nuclei on alumina crystal growth was also discussed. Finally, a theoretical basis and technical support for preparing high-performance, low-cost, and high thermal conductivity alumina fillers was provided. [Display omitted] [ABSTRACT FROM AUTHOR]

In this work, the thermal stability of nanocrystalline (NC) AZ31/TiB2 magnesium matrix composites was investigated, while the microstructure evolution and mechanical properties were analyzed. The results indicated the AZ31/TiB2 still maintained NC structure after annealing at 350 °C for 180 min. Even at the high annealing temperature of 400 °C and 450 °C for 180 min, their average grain size just reached about 124 nm and 155 nm, indicating excellent thermal stability. The TiB2 particles with sub-micron size uniformly distributed in Mg matrix had no change in size and no reaction with matrix during the annealing treatment. Due to the strong Zener pinning effect of TiB2 particles, the grain growth of Mg matrix at high temperature was effectively inhibited. Meanwhile, the solution and precipitation behavior of Al atoms were completed in a short time, due to the existence of many grain boundaries and structural defects. By calculation, the grain growth kinetics was described by the kinetics equation D 8 - D 0 8 = k t and the activation energy Eg for grain growth was 131.6 kJ/mol, which was much higher than that of pure Mg (92 kJ/mol). Due to their excellent thermal stability, the decrease in both compressive yield strength and ultimate compressive strength was no more than 12.2% after annealing treatment. Even annealing at 450 °C for 180 min, the CYS and UCS of the samples were still above 283 MPa and 295 MPa, respectively. [ABSTRACT FROM AUTHOR]

In the context of globalization, the international common language is English and it is more and more widely used. However, there is a shortage of talents with high English proficiency in all industries. According to the demand of the Chinese market, we should pay attention to students' English language ability. Deep learning is a machine learning method based on feature learning and feature hierarchical structure, which simulates the analysis and learning of the human brain, carries out feature transformation layer by layer, trains a single-layer network each time, and transforms the features of samples in the original space to a new feature space, thus making classification or prediction easier. There are still some defects in the current machine translation (MT) results of online MT, especially the disadvantages of low efficiency and low accuracy of MT when the full-text range uses the server to compare the data of different languages to obtain the grammar and text-related rules among different languages. Therefore, other modern intelligent recognition technologies should be adopted to achieve accurate English MT. Generally speaking, the closer the training data is to the domain of the target text, the higher the quality of sentence alignment and the more sentence pairs, the more helpful it is to learn more accurate translation rules, so as to obtain a more robust translation. [ABSTRACT FROM AUTHOR]

With photoconductor being transferred and separated, interface contact plays a crucial role in developing composites photocatalyst. In the present work, 2D crystalline g-C 3 N 4 (called as CCN) with 2D TiO 2 nanosheets (called as TO) obtained in situ oxidized single-layered Ti 3 C 2 T x MXene is designed by an electrostatic self-assembly technology. This CCN/TO nanosheets system with a few TiO 2 nanosheets distributed to the surface is not only prolonging lifetime of photoelectron but also stimulating photogenerated carriers transferred in contact interface. The electron transfer mechanism of CCN/TO is further proved by Pt photo-deposition method. Therein, the optimal CCN-TO-0.6 exhibits excellent performance of H 2 generation compared with single photocatalyst of CCN. The result shows that the crystalline g-C 3 N 4 photocatalysts introduced TiO 2 with interfacial effect favorably reduce H+ to H 2 and enhance photocatalytic activity. • The photocatalytic composites were synthesized by electrostatic self-assembly. • The 2D TiO 2 was obtained by in situ oxidized ultrathin Ti 3 C 2 T x MXene. • The composite role in light-excited carrier transfer and separation is described. • The effect of compound ratio of photocatalytic H 2 production was discovered. • The sample of 1:0.01 composite ratio showed the best photocatalytic activity. [ABSTRACT FROM AUTHOR]

Amine-functionalized graphitic carbon nitride decorated with small-sized Au nanoparticles exhibited the enhanced photocatalytic activity for CO 2 reduction under visible-light irradiation. • Amine-functionalized graphitic carbon nitride decorated with Au nanoparticles was prepared. • CN/Au exhibited enhanced photocatalytic activity for CO 2 reduction. • Time-of-flight secondary ion mass spectrometry confirmed the introduction of amino groups. • The introduced amino group improved the adsorption capacity of CN/Au for CO 2. Amine-functionalized graphitic carbon nitride (g-C 3 N 4) decorated with Au nanoparticles (CN/Au) was prepared by N 2 plasma treatment of g-C 3 N 4 powders impregnated with HAuCl 4 ·3H 2 O. Well-dispersed Au nanoparticles with a small particle size were deposited on g-C 3 N 4 nanosheets. In addition, the amino group was introduced into the CN/Au system. Without the addition of cocatalyst and sacrificial agent, CN/Au exhibited enhanced photocatalytic activity for CO 2 reduction under visible-light irradiation. CO and CH 4 evolution rates of CN/Au reached 28.3 and 1.3 μmol·h−1·g−1, which were 7.6 and 2.6 times higher than those of pristine g-C 3 N 4 (CN-0), respectively. The enhanced activity can be explained by these factors. (1) The introduced amino group improved the adsorption capacity of CN/Au for CO 2 ; (2) the hot electrons generated by Au nanoparticles activated the surrounding electrons through energy transfer and caused local temperature to rise, increasing the efficiency of the photoreduction reaction of CO 2 ; (3) the Schottky junction between Au and g-C 3 N 4 promoted the migration of electrons from g-C 3 N 4 to Au nanoparticles, suppressing the recombination of the carriers. Time-of-flight secondary ion mass spectrometry confirmed the introduction of amino groups, and solid-state 13C nuclear magnetic resonance spectra provided a support for inferring the position of the amino group. [ABSTRACT FROM AUTHOR]

The electrochemical production of hydrogen peroxide (H2O2) using metal‐free catalysts has emerged as a viable and sustainable alternative to the conventional anthraquinone process. However, the precise architectural design of these electrocatalysts poses a significant challenge, requiring intricate structural engineering to optimize electron transfer during the oxygen reduction reaction (ORR). Herein, we introduce a novel design of covalent organic frameworks (COFs) that effectively shift the ORR from a four‐electron to a more advantageous two‐electron pathway. Notably, the JUC‐660 COF, with strategically charge‐modified benzyl moieties, achieved a continuous high H2O2 yield of over 1200 mmol g−1 h−1 for an impressive duration of over 85 hours in a flow cell setting, marking it as one of the most efficient metal‐free and non‐pyrolyzed H2O2 electrocatalysts reported to date. Theoretical computations alongside in situ infrared spectroscopy indicate that JUC‐660 markedly diminishes the adsorption of the OOH* intermediate, thereby steering the ORR towards the desired pathway. Furthermore, the versatility of JUC‐660 was demonstrated through its application in the electro‐Fenton reaction, where it efficiently and rapidly removed aqueous contaminants. This work delineates a pioneering approach to altering the ORR pathway, ultimately paving the way for the development of highly effective metal‐free H2O2 electrocatalysts. [ABSTRACT FROM AUTHOR]

In present work, a novel Co-free (CrFeNi 2) 100- x Y x (x = 0, 3, 6, 9) medium entropy alloys (MEAs) were successfully prepared by vacuum arc-melting method. The results revealed that the addition of rare-earth element Y had a great effect on the phase composition of CrFeNi 2 MEA, which was transformed from the single FCC phase structure to the duplex structure of the FCC and HCP (YNi 5 type) phases. Meanwhile, the phase evolution of the current alloy system was evaluated using the previous criteria (ΔH mix - δ , Ω - δ , Δ χ , VEC and Λ). In addition, the volume fraction of the HCP phase increased significantly with the increasing Y content, which caused the obvious grain refinement. On the other hand, the nanoindentation test results revealed that the nanohardness of the HCP phase (∼10.7 GPa) was more than three times of the FCC phase (∼3.4 GPa). The dislocation nucleation types of the FCC phase (3.68 GPa) and the HCP phase (6.46 GPa) were discussed by calculating their maximum initial plastic shear stress. With the increasing Y content, both the hardness and strength of the alloy were significantly improved, but the plasticity deteriorated. The second phase strengthening played a dominant role in the strength improvement of (CrFeNi 2) 100- x Y x MEAs, while both the solid solution strengthening and grain boundary strengthening contributed slightly to the strength increment. • The expensive Co elements were replaced with atoms by the lower-cost Ni element to reduce costs. • Phase precipitation behavior and mechanical properties of (CrFeNi 2) 100- x Y x (x = 0,3,6,9) MEAs were investigated for the first time. • The differences in mechanical properties and deformation behavior of FCC and HCP phases were explored. • The yield strength and hardness of (CrFeNi 2) 100- x Y x (x = 9) MEAs were increased to 1265 MPa and 485HV, respectively. [ABSTRACT FROM AUTHOR]

Graphical abstract Highlights • Ultrafine-grained Ti/AZ31 magnesium matrix composites were prepared by powder metallurgy. • AZ31 alloys distributed uniformly by submicron/nanometer sized titanium were obtained. • The strengthening mechanisms for Ti/AZ31 composites at room temperature were analyzed quantitatively. • Outstanding strength at elevated temperature of ultrafine-grained Ti/AZ31 composites was confirmed experimentally. Abstract The microstructure of ultrafine grain for magnesium alloys can result in drastic enhancement in their room temperature strength, but the issue of low strength at elevated temperature becomes more serious as well due to grain boundary slide. Here ultrafine-grained Ti/AZ31 magnesium matrix composites with high strength at both room and elevated temperature were prepared by vacuum hot pressing and subsequent hot extrusion. The microstructure of the composite samples before and after consolidation processing was characterized, and the mechanical properties of the as-consolidated bulk samples were measured at room and elevated temperatures. The results indicate that after extrusion ultrafine-grained magnesium alloys were obtained and Ti particulates with particulate size of ∼310 nm disperse in Mg matrix. The magnesium grain of AZ31-15at.%Ti grows from 66 nm to 800 nm. Meanwhile, the relative densities of Ti/AZ31 composites are higher than 99%. The yield strength (YS) of extruded AZ31-15at.%Ti composite at room temperature is 341 MPa, being 2.4 times higher than original AZ31 alloy. Theoretical estimation shows that remarkably enhanced room-temperature mechanical strength attributes to grain boundary strengthening with the contribution ratio of 74%. In addition, the peak stress of extruded AZ31-15at.%Ti composite at 573 K is 82 MPa and ultrafine Ti dispersions are responsible for the enhanced strength. [ABSTRACT FROM AUTHOR]

Abstract: Efficient and affordable synthesis of graphene at low temperatures remains a significant challenge that potentially limits the use of this material in real‐life applications. We describe here a simple, efficient, highly controllable technique to synthesize graphene by sputtering carbon from a solid source with the assistance of inductively coupled plasma (ICP), followed by controllable low‐temperature annealing at about 550 oC. Raman scattering and X‐ray diffraction characterizations have revealed the formation of a few layer graphene of high quality, confirmed by a low (∼0.48) ID/IG ratio. Raman analysis of samples formed at various annealing temperatures has revealed an upper limit for annealing temperature of 585 oC, beyond which the formed graphene reversibly dissolves in the metal. The ICP‐assisted process was innovatively employed to improve the quality of thus‐fabricated graphene at low temperatures. The mechanism of graphene formation was attributed to the metal induced graphitization in combination with the carbon precipitation onto the catalyst surface. [ABSTRACT FROM AUTHOR]

The nanocrystalline AZ31 magnesium (Mg) alloy with 18 wt% titanium (Ti) addition was isothermally annealed in the temperature range of 300–400 °C for different durations. A study on the thermal stability, including solid solubility evolution, phase transformation, grain growth kinetics and hardness evolution, was carried out. The microstructure evolution at elevated temperatures was investigated by the means of X-ray diffraction (XRD), scanning electron microscope (SEM), transmission electron microscope (TEM) and high angle annular dark field (HAADF). Based on lattice parameters evolution and TEM observation, it was confirmed that the Ti element precipitated from Mg matrix as Ti phase. After the material being annealed at 400 °C for 300min, as to the original Ti particulates, there is no segregation and growth with the average particulate size being approximately 367 nm, meanwhile, magnesium matrix shows limited grain coarsening with the average grain size increasing from 95 nm to 210 nm. In addition, the grain growth kinetics could be well described by the kinetics equation, D 7 − D 0 7 = k t . The activation energy for grain growth was calculated to be 120 kJ/mol, which is about 28 kJ/mol greater than that of pure Mg. Simultaneously, the stability of mechanical property was investigated by microhardness evolution at different annealing temperatures. It was found that after this material being annealed at 400 °C for 300min, the microhardness remained 105HV, which is two times larger than that of the as-cast AZ31 Mg alloy. [ABSTRACT FROM AUTHOR]

The compact VDW heterojunctions and Zn/Cd molar ratios modulation induces the interfacial Cd-N bonds between Zn x Cd 1-x S and g-C 3 N 4 for efficient charge separation, leading to an enhanced CO 2 photoreduction. [Display omitted] • 2D/2D Zn x Cd 1-x S/g-C 3 N 4 photocatalysts was prepared through solvothermal method. • Zn x Cd 1-x S/g-C 3 N 4 exhibited enhanced photocatalytic activity for CO 2 reduction. • The Van der Waals heterojunctions was modulated by the interface engineering. • The interfacial Cd-N bonds function as an electron transport bridge to accelerate charge transfer directionally. The fabrication of Van der Waals (VDW) heterojunctions between two-dimensional materials has recently sparked the curiosity of researchers due to their compact interfaces, low energy barriers and efficient interfacial electron mobility efficiency. However, the relatively weak VDW interactions and VDW gap inhibits the migration of carriers across layers. Herein, we developed a novel 2D/2D Zn x Cd 1-x S/g-C 3 N 4 catalysts for regulating VDW heterojunctions by the interface engineering. Zn x Cd 1-x S nanosheets are strongly coordinated with g-C 3 N 4 , and the compact VDW heterojunctions and Zn/Cd molar ratios modulation induces Cd-N bonds to modulate the electronic structure at the interface. Evidenced by the experimental and theoretical calculation analysis, the constructed interfacial Cd-N bonds could function as a novel electron transport bridge between Zn 0.8 Cd 0.2 S and g-C 3 N 4 , enabling the photogenerated electron-hole pairs to be efficiently migrated directionally across the interlayer potential barrier. Therefore, Zn 0.8 Cd 0.2 S/g-C 3 N 4 exhibits the enhanced CO 2 reduction performance that is 3.2 times better than that of pure g-C 3 N 4 without the usage of co-catalysts or sacrificial agents. This work introduces an avenue to regulate Van der Waals heterojunctions and provides an efficient photocatalyst for green energy conversion. [ABSTRACT FROM AUTHOR]

The twinning evolution of a typical nickel-based superalloy was investigated by means of isothermal compression tests in the temperature range of 960–1160 °C and strain rate range of 0.001–1 s −1 . During hot deformation, the original Σ 3 boundaries lost their Σ 3 misorientation due to crystal rotations, while lots of new Σ 3 boundaries were formed mainly by growth accidents. With the increasing temperature and decreasing strain rate, the distributions of twin boundaries became more and more uniform, while the length and width of twin boundaries increased in size. In particular, the existing twins promoted the formation of more additional stacking error, and resulted in the occurrence of twinning adjacent to the existing twins, which coalesced with the existing twins and increased the twin width. Moreover, the fraction and density of Σ 3 boundaries increased with the increasing deformation temperature and decreasing strain rate firstly, and then they decreased again. At the higher temperature and lower strain rate, the accelerating grain growth inhibited the occurrence of twinning, leading to the decreasing fraction and density of Σ 3 boundaries. On the other hand, the higher deformation temperature and lower strain rate would also lead to the lower fraction of incoherent Σ 3 boundaries, the reason of which was also discussed. [ABSTRACT FROM AUTHOR]

Mechanical milling was used to prepare nanocrystalline AZ31 magnesium (Mg) alloy with titanium (Ti) addition. During milling, the crystallite size of the AZ31 Mg matrix decreased steadily with the increase of milling time. After milling for 110 h, the crystallite size of the Mg phase of the alloy with 18 wt.% and 27 wt.% Ti additions was refined to 86 nm and 66 nm respectively, leading to the formation of a nanocrystalline Mg matrix microstructure. Meanwhile, the size of Ti particles added in the alloy also decreased gradually with the increase of milling time, and the Ti dispersions presented a positive effect on the refinement of the Mg matrix grains. By milling for 110 h, the average size of Ti particles was refined to less than 1 μm in the AZ31 Mg alloy with 18 wt.% Ti addition. After mechanical milling, the as-milled powders were cold pressed into green compacts, and the mechanical properties were characterized by Vickers' hardness and uni-axial compressive tests. It was found that the micro-hardness of mechanically milled AZ31 Mg alloy with 27 wt.% Ti addition reached about 147 Hv, which was almost three times larger than that of the as-received AZ31 Mg alloy. Meanwhile, the yield strength of mechanically milled Ti-added AZ31 Mg alloy was seen to be as high as 293 MPa at room temperature and 60 MPa at 300 °C, respectively. [ABSTRACT FROM AUTHOR]

• The modified EPDM significantly improved the mechanical property of the composite coatings. • Coatings with both infrared stealth and low dielectric property. • Comparison of modification effects of AA and MAH monomers. Composite coating materials or structures with low infrared emissivity and high radar transmittance are in urgent need in practical applications, among which binder is one of the important factors affecting the mechanical properties, infrared and dielectric properties of coatings. Acrylic acid (AA) and maleic anhydride (MAH) were used as graft monomers to modify ethylene propylene diene monomer (EPDM) binder. Composite coating with low infrared emissivity and low dielectric properties was prepared by using modified EPDM as binder, floating aluminum (Al) powder and antistatic carbonaceous fiber (CF) as filler. The effects of the type and amount of modified monomer on the mechanical properties, infrared emissivity and dielectric properties of the binder and the composite coating were systematically studied. The results show that the tensile strength (σ b) and elongation at break (e) of the composite coating can be increased by 32% and 18%, respectively, by appropriate grafting modification of the binder. The infrared emissivity and the dielectric properties of the composite coating has a slight change with the increase of graft monomer content. Grafting modification of the binder improves the compatibility, wettability and interfacial bonding between filler and binder, which remarkably enhanced the mechanical and comprehensive properties of the composite coating. The effect mechanism of grafting modification of AA and MAH is disclosed from the aspects of polarity, branching and crosslinking. This work increases the selection range of binders needed to prepare low infrared emissivity materials. [ABSTRACT FROM AUTHOR]

In order to improve the efficiency and reduce the labor cost of cafeterias, an intelligent master–slave collaborative robot system is developed for cafeteria service in this paper. The developed system can automatically complete the tasks of scooping dishes, taking bowls and pouring dishes into the bowl based on master–slave collaboration. Specifically, a dynamic geometry feature graph convolution network (DGG) is devised using the 3D point cloud of the dish, which can efficiently predict the scooping positions of the different dishes. Moreover, a master–slave motion planning control method is proposed to achieve fast and smooth trajectories for both arms, which can accomplish the cafeteria service tasks collaboratively. Furthermore, we establish a dataset containing point clouds and color images of various Chinese food. Experiments demonstrate that the DGG network can achieve superior performance over other state-of-the-art point cloud segmentation networks. Besides, the designed robot system can well meet the requirements of operation accuracy and speed, confirming its practicality in cafeteria services. • An intelligent master–slave collaborative robot system is developed for cafeteria service. • A novel point cloud segmentation network DGG is devised to predict the scooping positions of different dishes. • Using the master–slave motion planning, the proposed system can realize efficient and close coordination. [ABSTRACT FROM AUTHOR]

The method of mechanical milling was applied to synthesize nanocrystalline Mg x Ti 100 − x ( x = 95, 90, 85) composite powders. The results reveal that mechanical milling is an effective method for preparing Mg–Ti composite powders, which consist of nanocrystalline Mg matrix and fine dispersed Ti particles. Moreover, the microstructure evolution and morphology of the as-milled powders were observed, and the corresponding mechanisms were also discussed. After milling for 60 h, the crystallite size of the matrix Mg in Mg x Ti 100 − x ( x = 95, 90, 85) composite powders was refined to 105 nm, 84 nm, and 76 nm, respectively. Meanwhile, the average size of the dispersed Ti particles in Mg x Ti 100 − x ( x = 90) composite powders was refined to about 1 μm. Based on the XRD data, the solid solubility of Ti in Mg was calculated by using the Vegard's law. For all these Mg–Ti composite powders, the solid solubility of Ti in Mg seemed to be closely related with the milling time and the content of Ti. In the 60 h-milled Mg x Ti 100 − x ( x = 95, 90, 85) composite powders, the solid solubility of Ti in Mg was estimated to be 0.56 at.%, 1.32 at.% and 2.35 at.%, respectively. [ABSTRACT FROM AUTHOR]

• A series of 2,4-dianilinopyrimidine derivatives as potent dual JAK2 and HDAC inhibitors were synthesized. • Compound 7l demonstrated balanced and considerable inhibitory activity against JAK2 and HDAC1. • Compound 7l exhibited potent anticancer activity against tested cancer cell lines (A549, HepG-2, MDA-MB-231 and Jurkat). • Compound 7l induced cell death via apoptosis and cell cycle arrested in a dose-dependent manner. Dual or multiple-targeting inhibition of oncogenic targets in a single molecule could be an alternative approach to drug combinations. Previous studies have revealed that histone deacetylases (HDAC) inhibitor in combination with janus kinase (JAK) inhibitor could exhibit synergistically anti-proliferative effects in cancer treatment. Herein, we presented a novel series of 2,4-dianilinopyrimidine derivatives, which could simultaneously inhibit JAK2 and HDAC1. Among which, 7l was found to be the most potent compound and displayed balanced inhibitory activity against HDAC1 (IC 50 = 1.9 nM) and JAK2 (IC 50 = 0.5 nM), respectively. 7l also demonstrated good antiproliferative activity against tested cancer cell lines (A549, HepG-2, MDA-MB-231 and Jurkat). Moreover, flow cytometric analysis showed that 7l induced apoptosis and cell cycle arrest in a dose-dependent manner, and the insight into mechanisms of 7l indicated that it could decrease the phosphorylation of STAT-3 and promote histone acetylation. In conclusion, these results together suggested that 7l would be a promising lead candidate and deserved further research and development. [Display omitted] [ABSTRACT FROM AUTHOR]

An efficient synthetic method for 2, 3-dihydro-1 H-indene-1-methanamine and its derivatives is described. Six compounds of 2, 3-dihydro-1 H-indene-1-methanamines were synthesized from corresponding 4-nitro-3-phenylbutanoic acid in satisfactory yields (50.9-57.9 % in 4 steps), and three compounds ( 1c, 1e, 1f) were newly reported. This procedure has the advantages of mild conditions, less pollution, and simple manipulation. [ABSTRACT FROM AUTHOR]

• Floating aluminum powder coated with SiO 2 was prepared using tetraethyl orthosilicate (TEOS) as raw material by sol-gel method. • The composite coating was prepared using modified Al powder and antistatic carbonaceous fiber (CF) as filler, EPDM as binder. • The composite coating that we prepared has low infrared emissivity compatible with high radar wave transmittance. Low infrared emissivity coatings have been widely used in many fields. At present, there are few researches on coatings that are compatible with low infrared emissivity and high radar wave transmittance. In this paper, floating aluminum (Al) powder coated with SiO 2 was prepared using tetraethyl orthosilicate (TEOS) as raw material by sol-gel method. The composite coating was prepared using modified Al powder and antistatic carbonaceous fiber (CF) as filler, EPDM as binder. The surface morphology, infrared absorption properties of the modified Al powder and the infrared emissivity, surface resistivity, electromagnetic properties and mechanical properties of the composite coating were analyzed. The results show that with the increase of TEOS addition amount, more SiO 2 was covered to the surface of floating Al powder. By adjusting the thickness of the surface modification layer of floating Al powder, the dielectric constant (ε) and dielectric loss tangent values (tanδ) of the composite coating were significantly reduced. When the addition amount of TEOS is 1 g for Al@SiO 2 , the ε and tanδ can be significantly reduced, and the infrared emissivity was less than 0.6, the tensile strength (σ b) and elongation rate at break (e) decreased slightly. This suggests that the composite coating has low infrared emissivity compatible with high radar wave transmittance was obtained, which is expected to be applied to the surface of aircraft radome. [ABSTRACT FROM AUTHOR]

Although formation of urothelial carcinoma of the bladder (UCB) requires multiple steps and proceeds along divergent pathways, the underlying genetic and molecular determinants for each step and pathway remain undefined. By developing transgenic mice expressing single or combinatorial genetic alterations in urothelium, we demonstrated here that overcoming oncogene-induced compensatory tumor barriers was critical for urothelial tumor initiation. Constitutively active Ha-ras (Ras*) elicited urothelial hyperplasia that was persistent and did not progress to tumors over a 10 months period. This resistance to tumorigenesis coincided with increased expression of p53 and all pRb family proteins. Expression of a Simian virus 40 T antigen (SV40T), which disables p53 and pRb family proteins, in urothelial cells expressing Ras* triggered early-onset, rapidly-growing and high-grade papillary UCB that strongly resembled the human counterpart (pTaG3). Urothelial cells expressing both Ras* and SV40T had defective G1/S checkpoint, elevated Ras-GTPase and hyperactivated AKT-mTOR signaling. Inhibition of the AKT-mTOR pathway with rapamycin significantly reduced the size of high-grade papillary UCB but hyperactivated mitogen-activated protein kinase (MAPK). Inhibition of AKT-mTOR, MAPK and STAT3 altogether resulted in much greater tumor reduction and longer survival than did inhibition of AKT-mTOR pathway alone. Our studies provide the first experimental evidence delineating the combinatorial genetic events required for initiating high-grade papillary UCB, a poorly defined and highly challenging clinical entity. Furthermore, they suggest that targeted therapy using a single agent such as rapamycin may not be highly effective in controlling high-grade UCB and that combination therapy employing inhibitors against multiple targets are more likely to achieve desirable therapeutic outcomes. [ABSTRACT FROM AUTHOR]

Abstract: A novel method for the determination of nucleic acids by using silver nanoparticle (AgNPs)–eriochrome black T (EBT) as a resonance light scattering (RLS) probe has been developed. Under optimum conditions, there are linear relationships between the quenching extent of RLS intensity and the concentration of nucleic acids in the range of 4.0×10−9–4.0×10−7, 4.0×10−7–1.6×10−6 gmL−1 for fish sperm DNA (fsDNA) and 4.0×10−8–2.0×10−6 gmL−1 for yeast RNA (yRNA). Their detection limits (S/N=3) are 2.0ngmL−1 and 21ngmL−1, respectively. The results indicate that AgNPs can form wirelike aggregates and nanoslices in the presence of the EBT. Whereas, when nucleic acids are added into the AgNPs–EBT system, the dynamic balance of AgNPs–EBT system is destroyed and the nanoparticles undergo dispersion again, leading to the RLS intensity of AgNPs–EBT system quenching. Meanwhile, the conformation of fsDNA is changed by the synergistic effect of AgNPs and EBT. [ABSTRACT FROM AUTHOR]

It is found that silver nanoparticles (AgNPs) can further enhance the fluorescence intensity of curcumin (CU) - cetyltrimethylammonium bromide (CTAB) – nucleic acids and improve its anti-photobleaching activity. Under optimum conditions, the enhanced fluorescence intensity is proportion to the concentration of nucleic acids in the range of 2.0 × 10−8–1.0 × 10−6 g mL−1 for fish sperm DNA (fsDNA), 2.0 × 10−8–1.0 × 10−6 g mL−1 for calf thymus DNA (ctDNA), 1.0 × 10−8–1.0 × 10−6 g mL−1 for yeast RNA (yRNA), and their detection limits (S/ N = 3) are 8.0 ng mL−1, 10.5 ng mL−1 and 5.8 ng mL−1, respectively. This method is used for determining the concentration of DNA in actual sample with satisfactory results. The interaction mechanism is also studied. [ABSTRACT FROM AUTHOR]

Abstract: It is found that Al(III) can further enhance the intensity of resonance light scattering (RLS) of the silver nanoparticles (AgNPs) and nucleic acids system. Based on this, a novel method of determination of nucleic acids is proposed in this paper. Under optimum conditions, there are linear relationships between the enhancing extent of RLS and the concentration of nucleic acids in the range of 1.0×10−9–1.0×10−7 gmL−1, 1.0×10−7–2.0×10−6 gmL−1 for fish sperm DNA (fsDNA), 1.0×10−9–7.0×10−8 gmL−1 for calf thymus DNA (ctDNA) and 1.0×10−9–1.0×10−7 gmL−1 for yeast RNA (yRNA). The detection limits (S/N=3) of fsDNA, ctDNA and yRNA are 4.1×10−10 gmL−1, 4.0×10−10 gmL−1 and 4.5×10−10 gmL−1, respectively. The studies indicate that the RLS enhancement effect should be ascribed to the formation of AgNPs–Al(III)–DNA aggregations through electrostatic attraction and adsorption bridging action of Al(III). And the sensitivity and stability of the AgNPs–fsDNA system could be enhanced by Al(III). [Copyright &y& Elsevier]

The functional properties of a novel protein, protein disulfide isomerase-related protein A (PRPA) from Aspergillus niger T21, have been characterized. (1) PRPA possesses disulfide isomerase activity. (2) In Hepes buffer, at substoichiometric concentrations, PRPA facilitates the formation of inactive lysozyme aggregates associated with PRPA (anti-chaperone activity); while at a high molar excess, PRPA inhibits aggregation by maintaining lysozyme in a soluble, yet inactive, state (chaperone-like activity). However, PRPA only exhibits chaperone-like activity during lysozyme refolding in phosphate buffer. (3) Experiments have indicated that disulfide cross-linkage is not required for the interaction between PRPA and lysozyme, and hydrophobic interaction may be responsible for PRPA effect on lysozyme. (4) Co-expression of PRPA and prochymosin in Escherichia coli leads to reduction of inclusion bodies, rendering part of prochymosin molecules soluble yet inactive. The structural and functional characteristics of PRPA suggest that PRPA may play an important role in protein folding, aggregation, and retention in the endoplasmic reticulum. [Copyright &y& Elsevier]

• Sulfur host prepared by a unique dual-channel electrospinning method. • WS 2 /WO 3 and MoS 2 /MoO 3 heterostructures enabling anchor of LiPSs. • WX 2 and MoX 2 realized LiPSs adsorption and catalytic conversion. • Excellent energy storage performance is in both coin cell and pouch cell. Due to the dissolution of Lithium polysulfides (LiPSs), the volume expansion, and poor conductivity, practical applications of Lithium-sulfur batteries (LSBs) are not satisfactory. Herein, dual-heterostructure decorated interweaved carbon nanofibers are proposed as sulfur hosts to significantly improve the energy storage behavior of LSBs. The unique structure of the interweaved carbon nanofibers and heterostructures provides more transmission channels for electrons and ions while also accelerating the process. Moreover, the heterostructures induce chemical anchoring and catalytic conversion of LiPSs. As a result, the cathode in the coin cell delivers an initial capacity of 777.9 mAh g−1 at 1C and high retention of 68.59% after 600 cycles. In the pouch cell, the cathode delivers a discharge capacity of 907.8 mAh g−1 and a reversible charging capacity of 913.1 mAh g−1 for the first cycle with an ultra-high sulfur loading up to 9.136 mg cm−2. Beyond that, density functional theory calculations, X-ray photoelectron spectroscopy, symmetric cell, and Li 2 S nucleation tests were adopted to verify the adsorption and catalytic conversion mechanisms of the cathode. This excellent interweaved dual-heterostructure sulfur host provides a novel structural design strategy for efficient chemical adsorption and catalytic conversion of LiPSs, as well as more opportunities for the commercial application of LSBs. [ABSTRACT FROM AUTHOR]

• Coatings with both infrared stealth and electrostatic dissipation properties. • Effects of doping ratio of AZO, pigment content on properties were discussed. • Confirming the synergy effect of AZO and CF in difunctional coatings. The functional coatings play a critical role in many fields. To obtain difunctional composite coatings with low infrared emissivity and electrostatic dissipation (ESD) property, the composite coatings reinforced by aluminum-doped zinc oxide (AZO) and ESD carbonaceous fiber (CF) hybrid pigments were prepared, which were characterized by X-ray diffraction, scanning electron microscopy, infrared emissometer and insulation resistance tester. The effects of Al doping ratio of AZO, pigment adding amount and pigment type on the infrared emissivity and surface resistivity of the composite coating have been studied. The results confirmed that AZO of 7at.% doping concentration has lower infrared emissivity, and the infrared emissivity of AZO and CF coatings decreases with the increase of filler content. When AZO and CF are mixed at 1:1, the surface resistivity of the coating is 6380 Ω, which is much lower than that of any single pigment coating. Their synergy effect was contributed to form a continuous conductive path in the coating, enhance the tunnel current and obtain low surface resistivity for electrostatic dissipation. This work provides a new strategy for developing difunctional composite coatings with low infrared emissivity and electrostatic dissipation property. [ABSTRACT FROM AUTHOR]

Betulinic acid (BA) is a new class of anticancer drug, but its relatively short half-life and poor water solubility limit its therapeutic effect and clinical application. Herein, to tackle the dilemma, BA prodrugs were prepared by conjugating BA onto the polyethylene glycol (PEG) polymer via cleavable disulfide bonds. The prodrugs exhibited high water solubility (270-fold of free BA) and a relatively high drug-loading efficiency of 14.2 %. To further endow the BA prodrugs with a photothermal therapeutic effect, the near-infrared (NIR) agent Cypate was grafted on the Pluronic triblock copolymer. The different PEG polymers and different Pluronic polymers were chosen to obtain the optimal drug loading efficiency and the photothermal generation effect. The P-SS-BA/F68-Cy prodrug micelles integrate the redox-responsive BA prodrugs and the NIR-responsive amphiphilic triblock polymer into one single nanocomposite. The release of BA was less than 20 % in pH 7.4 PBS in the absence of glutathione (GSH), whereas the release of BA was obviously accelerated in pH 5.0 PBS with 10 mM GSH. In addition, the release of BA was further accelerated under the NIR irradiation. The P-SS-BA/F68-Cy micelles showed an excellent photothermal heating effect under NIR irradiation. The prepared P-SS-BA/F68-Cy micelles showed the synergistic thermochemotherapeutic effect on tumors both in vitro and in vivo. Therefore, the present study shows the great potential of dual-triggered drug delivery and thermochemotherapy for combination therapy. [ABSTRACT FROM AUTHOR]

The ability to tailor a new crystalline structure and associated functionalities with a variety of stimuli is one of the key issues in material design. Developing synthetic routes to functional materials with partially absorbed nonmetallic elements (i.e., hydrogen and nitrogen) can open up more possibilities for preparing novel families of electronically active oxide compounds. Fast and reversible uptake and release of hydrogen in epitaxial ABO3 manganite films through an adapted low‐frequency inductively coupled plasma technology is introduced. Compared with traditional dopants of metallic cations, the plasma‐assisted hydrogen implantations not only produce reversibly structural transformations from pristine perovskite (PV) phase to a newly found protonation‐driven brownmillerite one but also regulate remarkably different electronic properties driving the material from a ferromagnetic metal to a weakly ferromagnetic insulator for a range of manganite (La1−xSrxMnO3) thin films. Moreover, a reversible perovskite‐brownmillerite‐perovskite transition is achieved at a relatively low temperature (T ≤ 350 °C), enabling multifunctional modulations for integrated electronic systems. The fast, low‐temperature control of structural and electronic properties by the facile hydrogenation/dehydrogenation treatment substantially widens the space for exploring new possibilities of novel properties in proton‐based multifunctional materials. [ABSTRACT FROM AUTHOR]

A novel protocol for the direct halogenation of 8‐amidoquinoline derivatives with phase‐transition was reported. The reactions were promoted by benzyltriethylammonium chloride and dihalogenated hydantoin, using exclusively water as the solvent and achieving the C5‐halogenation products of amidoquinolines in moderated to excellent yields at room temperature. [ABSTRACT FROM AUTHOR]

We present detailed investigations of structural and static/dynamic magnetic properties of hydrogenated hcp-Co8057Fe4Ir16 soft magnetic thin films. Two different kinds of defects, i.e., destructive and non-destructive, were demonstrated by controlling the negative bias voltage of the hydrogenation process. Our results show that the structure and magnetic properties of our sample can be tuned by the density of the induced defects. These results provide better understanding of the hydrogenation effect and thus can be used in the future for materials processing to meet the requirements of different devices. [ABSTRACT FROM AUTHOR]

By introducing nanoscale disordered interfaces into the ordered superlattice grains can achieved a combination of ultra-high strength and excellent ductility in Ni 3 Al-type high-temperature alloys, but limited by the complex preparation process. In the present work, a Ni 3 (Al, Ti)-type multicomponent alloy of Ni 43.9 Co 22.4 Fe 8.8 Al 10.7 Ti 11.7 B 2.5 was successfully fabricated using laser metal deposition (LMD) technique. The microstructural evolution, tensile properties and strengthening mechanism were investigated. Microstructural and phase analyses of the sample reveale the presence of dendritic γ + γ′ phases, γ′ envelopes and interdendritic γ + γ′ phases in the alloy. The LMD prepared Ni 43.9 Co 22.4 Fe 8.8 Al 10.7 Ti 11.7 B 2.5 alloy exhibits superior mechanical property at both room temperature and elevated temperature. Compared to Ni 3 Al-type intermetallic alloys, the alloy exhibited excellent strength-ductility synergy at room temperature. In addition, the alloy's yield strength rises as temperature rises from 298 K to 973 K, reaching a maximum value of 1043 MPa at 973 K. The strength of the prepared Ni 43.9 Co 22.4 Fe 8.8 Al 10.7 Ti 11.7 B 2.5 alloy is mainly contributed by lattice friction strengthening, solid solution strengthening, precipitation strengthening and the inherent yield strength of γ′ envelopes with precipitation strengthening, and the inherent yield strength is the key factor. This work provides insight into the preparation of Ni 3 (Al, Ti)-type multicomponent alloy with superior mechanical property at both room temperature and elevated temperature by LMD. [ABSTRACT FROM AUTHOR]

[Display omitted] • The structure of MnOx@aTiOy showed the increasing capacity being activated to maintain for a long-term cycling (829.5 mAh g−1 at 1 A g−1 after 2000 cycles). • The oxygen defects in the coating layer of modified TiO 2 boosted the pseudocapacitance effect for electrochemical performance. • The DFT calculations reveals the oxygen defects, the transformation of α-MnO 2 into Bixbyite-O Mn 2 O 3 , would decrease the kinetics of Li+ on lithium migrating paths and energy barriers. In this work, we developed Manganese and Titanium based oxide composites with oxygen defects (MnO x @aTiO y) via plasma processing as anodes of lithium ion batteries. By appropriately adjusting the defect concentration, the ion transport kinetics and electrical conductivity of the electrodes are significantly improved, showing stable capacity retention. Furthermore, the incremental capacity is further activated and long-term stable cycling performance is achieved, with a specific capacity of 829.5 mAh/g at 1 A/g after 2000 cycles. To scrutinize the lithium migration paths and energy barriers in MnO 2 and Mn 2 O 3 , the density functional theory (DFT) calculations is performed to explore the lithium migration paths and energy barriers. Although the transformation of MnO 2 into Mn 2 O 3 through oxygen defects was initially surmised to inhibit Li ions along their standard routes, our results indicate quite the contrary. In fact, the composite's lithium diffusion rate saw a substantial increase. This can be accredited to the pronounced enhancement of conductivity and ion transport efficiency in the amorphous and porous TiO y. [ABSTRACT FROM AUTHOR]

Solar-driven photocatalytic hydrogen generation via splitting water requires an efficient visible light active photocatalyst. In this work, Ni cocatalysts on a TiO2 composite photocatalyst with different graphene oxide (GO) contents were prepared using a hydrothermal method and characterized by TEM, XRD, UV-vis, Raman and PL spectra. The results show that the synthesized TiO2/GO/Ni nanosheet composites have a large specific surface area and can provide a large number of active sites for a photocatalytic hydrogen production reaction. GO can broaden the optical absorption range of TiO2 and absorb more visible light, thus stimulating more photogenerated electron–hole pairs. At the same time, GO can collect electrons and promote the separation of photogenerated electron–hole pairs. Ni, as a cocatalyst, can be used as an active site for hydrogen ion adsorption, which is conducive to promoting the migration of photogenerated electrons in the system and prolonging the life of photogenerated electrons and holes, thus ensuring the high efficiency of the photocatalytic reaction. [ABSTRACT FROM AUTHOR]

Aqueous zinc-ion batteries (AZIBs) have received great attention owing to the increasing demand for safe and inexpensive batteries. However, their poor cycling issue hinders their commercialization and further application, resulting from the zinc dendrite growth, corrosion, and passivation that occur on the Zn anode, as well as the dissolution and cracking issue of active materials on the cathode. Herein, we introduce the use of a chelating agent triethanolamine (TEA) as an additive in the electrolyte to enhance the cycling stability of AZIBs. TEA molecules preferentially coordinate with Zn2+, replacing water molecules in the solvation sheath of Zn2+, thereby reducing the solvation effect in the electrolyte. Moreover the adsorbed interface layer on the anode Zn surface forms a stable solid–electrolyte interphase (SEI) while the cathode forms a cathode–electrolyte interphase (CEI), suppressing the side reactions and dendrite growth of metallic Zn and protecting the cathode from dissolution while increasing the diffusion rate of Zn2+. The Zn‖MnO2@CNT cell showed reversible and durable performance with 78% retention after 2000 cycles at 0.5 A g−1. [ABSTRACT FROM AUTHOR]

The vanadium particles reinforced AZ31 matrix composite (V P /AZ31) was prepared using the powder metallurgy method. Subsequently, hot deformation behavior of V P /AZ31 composite was studied through hot compression trials. The experimental parameters were set in a temperature range of 250–400 °C and a strain rate range of 0.001–1 s−1. Based on the experimental results, a strain-compensated Arrhenius constitutive model was developed to accurately forecast the flow behavior of V P /AZ31 composite. Moreover, the thermal activation energy was calculated to be 138.605 kJ/mol and the processing map was delineated according to the dynamic material model theory. The processing map revealed that the optimal processing area existed under 363–400 °C/0.001–0.004 s−1, where the efficiency of power dissipation exceeded 23 %. Notably, the highest efficiency of power dissipation occurred at 400 °C/1 s−1, which exceeded 30 %. Under these conditions, dynamic recrystallization (DRX) was sufficiently developed, indicating the enhancement of workability. It is estimated that the instability region for V P /AZ31 composites occurred within the conditions of 250–325 °C/0.16–1 s−1, characterized by crack formation. The DRX of V P /AZ31 composite is predominantly governed through the mechanism of discontinuous DRX (DDRX). • A strain-compensated Arrhenius constitutive model was developed to forecast the flow behavior of V P /AZ31 composite. • The thermal activation energy of V P /AZ31 composite is approximately 138.605 kJ/mol. • The processing map revealed that a safe processing range exists under 363–400 °C/0.004–0.001 s−1. • It is estimated that the instability region for V P /AZ31 composites occurs within the condition of 250–325 °C/0.16–1 s−1. • The dynamic recrystallization of V P /AZ31 composite is predominantly governed by discontinuous dynamic recrystallization. [ABSTRACT FROM AUTHOR]

The hot deformation behavior of a nickel-based superalloy was investigated by means of isothermal compression tests in the strain rate range of 0.001–10 s −1 at 1110 °C. Transmission electron microscope (TEM) and electron backscatter diffraction (EBSD) technique were used to study the effect of strain rate on the microstructure evolution of the alloy during hot deformation. The results revealed that the dynamic recrystallization (DRX) process was stimulated at high strain rates ( ε ̇ ⩾ 5 s - 1 ) due to the high dislocation density and adiabatic temperature rise. Meanwhile, high nucleation of DRX and low grain growth led to the fine DRX grains. In the strain rate rage of 0.001–1 s −1 , the volume fraction of DRX grains increased with the decreasing strain rate, and the grain growth gradually governed the DRX process. Moreover, the strain rate has an important effect on DDRX and CDRX during hot deformation. On the other hand, particular attention was also paid to the evolution of twin boundaries during hot deformation. It was found that there was a lower fraction of Σ 3 boundaries at the intermediate strain rate of 1 s −1 , while the fractions of Σ 3 boundaries were much higher at both the lower strain rates ( ε ̇ ⩽ 0.1 s - 1 ) and higher strain rates ( ε ̇ ⩾ 5 s - 1 ). [ABSTRACT FROM AUTHOR]

[Display omitted] To tackle the intrinsic inferior conductivity of the sodium ion batteries (SIBs) cathode Na 3 V 2 (PO 4) 3, transitional metal cation doping, and carbon frame design are employed for NASICON structural modification. Herein, a hard carbon skeleton Na 3+x V 2−x Zn x (PO 4) 3 NASICON structure is proposed resorting to the combination of flimsy hard carbon slices coating and Zn2+ doping along with the introduction of spare Na+. The structural distortion caused by the insertion of Zn2+ and Na+ broadens the transfer channels and increases diffusion routes for Na+. At the same time, the anchoring effect for Na 3+x V 2−x Zn x (PO 4) 3 nanoparticles brought by external hard carbon layers and pillar effect aroused by Zn2+ provide a stable and firm skeleton, which is conducive to structural stability and reversibility at high current density. Among various doping concentrations, Na 3.03 V 1.97 Zn 0.03 (PO 4) 3 performs a significantly enhanced rate performance with a reversible capacity up to 60 mAh·g−1 (40C) and ultra-long cycle life of 1000 cycles with a capacity retention of 92.6% at 5C. [ABSTRACT FROM AUTHOR]

This work discusses a Multilevel-Teaching Practice on GNSS Principle and Application for Undergraduates of Surveying and Mapping in China, underlining the fast development of remote sensing technology. We explore i) the multidisciplinary cross-combination transformation of the traditional GNSS education of remote sensing; ii) we combine theoretical knowledge and practical results in the field of navigation and positioning; iii) we highlight the cutting-edge, intersecting and comprehensive teaching content; innovate the construction of a practical teaching platform for GNSS theory, practice and innovation ability training. A multi-level theoretical and practical curriculum system has been established to strengthen the foundation and professional skills, and cultivate scientific and technological innovation. We propose a teaching method of "Hybrid Online/Offline Teaching", which makes use of the advantages of online/offline teaching form, effectively improving the quality of undergraduate teaching. In terms of practice and innovation ability training, we establish an open, diversified, research-based practice innovation-education platform based on virtual simulated experiments. The implementation of this teaching approach has achieved remarkable results on undergraduate training for GNSS education. [ABSTRACT FROM AUTHOR]

The NiLi-BC electrode forms regular interfacial electric field near the electrode surface, which is favorable to eliminate the local concentration polarization and induce the generation of the stable and long-term effective SEI during the Li plating and striping processes. As a result, the NiLi-BC electrode exhibits a Li dendrite-free feature and ultra-stable cycling performance with a low overpotential. [Display omitted] • Bimetallic composite induced ultra-stable solid electrolyte interphase on the surface of the electrode. • The bimetallic composite is contributed to uniform Li deposition. • The strategy is facile and effective enough to provide a feasible road for the engineering application of Li metal anode. Lithium metal is the most promising anode materials for the next generation lithium ion battery. However, the electrode polarization leads to the formation of dendrites and "dead lithium", which degrades the performance of lithium metal batteries and induce a variety of security risk. The electrode polarization and lithium dendrites can be suppressed by lithium metal composite electrode. Herein, a simple and effective strategy is adopted to construct nickel and lithium bimetallic composite (NiLi-BC) electrode by a double roll process. The Ni framework inside the electrode can optimize the electric field and Li+ distribution at the electrode/electrolyte interface and induce the uniform lithium deposition. As a result, the NiLi-BC exhibits a lithium dendrite-free feature and stable cycling performance under a low overpotential (<15 mV throughout 2180 h at 1 mA cm−2 with a deposition capacity of 1 mAh cm−2). Moreover, the assembled NiLi-BC||LiFePO 4 coin cell and pouch cell exhibit improved capability and stable cycling performance. Finally, the in-situ optical microscopy and in-situ Raman spectroscopy are employed to obtain a better understanding of the interfacial structure and chemical component during the Li plating and striping processes. The scheme of this study of the NiLi electrode has great practical application value. [ABSTRACT FROM AUTHOR]

Along with the rapid development of network technologies, the server-side of an e-commerce website is becoming more and more untrustworthy. Thus, how to prevent the disclosure of users' behavior privacy in online business activities has attracted people's wide attention. Aiming at the protection of users' commodity viewing privacy in a commercial website, this paper proposes to construct a group of dummy requests on a trusted client, then, which are submitted together with a user commodity viewing request to the untrusted server-side, so as to confuse and cover up the user preferences. First, we define a privacy model for a user commodity viewing service, in which we introduce a concept called entropy for commodity viewing probability to measure the confusion effect of dummy requests on user requests, and we introduce a concept called regional distance among commodity categories to measure the cover-up effect of dummy requests on users' commodity viewing preferences. Second, we design an implementation algorithm to generate a group of ideal dummy requests that can meet the constraints formulated in the privacy model. Finally, both theoretical analysis and experimental evaluation demonstrate the effectiveness of the proposed approach, i.e., which can improve the security of users' commodity viewing privacy on the untrusted server-side, without compromising the availability of an e-commerce website. In this paper, we present a valuable research attempt to the protection of users' behavior privacy in a commercial website, which is of positive significance for building a privacy-preserving e-commerce platform. [ABSTRACT FROM AUTHOR]

Li anode with a multicomponent protective layer (Ag/F/S-Li) protective layer at molecular level are designed and prepared. The Ag0 in Ag/F/S-Li has the ability to induce uniform Li+ distribution, while LiF/sulfide layer enable to reduce the side reaction between electrolyte and Li metal. This Ag/F/S-Li anode can cycle stably for 2000h. [Display omitted] • Rational construction of Ag0, LiF/sulfide enriched composition protection layer at molecular level for Li metal anode. • Ag0, LiF and sulfide in the layer are uniformy distributed. • The stability of Ag/F/S-Li anode is significantly enhanced and can be stably cycled for 2000 h. • Ag/F/S-Li||LFP, Ag/F/S-Li||LCO full cells and Ag/F/S-Li(or LiB)||MnO 2 primary cell exhibit excellent performance. Li metal is a promising anode material for high-energy–density batteries due to its high theoretical capacity and low redox potential. However, both the uncontrolled Li dendrite growth and unstable solid electrolyte interphase (SEI) layer restricts its large-scale practical applications. Herein, an artificial protective layer consisting of Ag nanoparticles, lithium fluoride (LiF) and sulfide are innovatively designed and fabricated via the in-situ chemical reaction between Ag(I) trifluoromethylthiolate (AgSCF 3) and Li metal. Density functional theory (DFT) results indicate that Ag nanoparticles have a high binding energy with Li atom and LiF/sulfide have wide band gap, which would provide plenty of nucleation sites for Li+ and reduce the direct contact between inner Li metal and the electrolyte. The co-existence of Ag and LiF/sulfide results in a strong synergistic effect, and this is confirmed by the systematical comparison with single modified Ag-Li and double modified F/S-Li anodes. Benefitting from this synergistic effect, the Ag/F/S-Li symmetrical cells can stably work for 2000 h with low-voltage hysteresis at current density of 1 mA cm−2. Full cells assembled with LiCoO 2 (LCO) and LiFePO 4 (LFP) cathodes displays much better long‐term cycle performance when the Ag/F/S-Li anode is applied. Furthermore, this Ag/F/S-Li modification can significantly enhance discharge capacity, rate performance, as well as energy density of Li(or LiB alloy)||MnO 2 primary cells. This promising work promotes the practical application of Li metal and provides new insight into the protective layer design in stable Li metal batteries. [ABSTRACT FROM AUTHOR]

Manganites (R1−xAxMnO3, R = rare-earth cation and A = alkali or alkaline earth cation) host an immense number of phases and electronic properties, which can be mainly manipulated through conventional structural control such as metallic cations, oxygen concentration, or misfit strain. However, their practical applications are heavily hindered due to the requirement of rigid synthesis conditions and prolonged treatment time. Herein, a subtle hydrogenation of canonical epitaxial La0.3Sr0.7MnO3 films gives rise to a series of structural transformations ranging from the perovskite to the intermediate state and to the brownmillerite one, accompanied by tunable electronic performances from the antiferromagnetic insulating phase to the weak magnetic insulating one. Moreover, the hydrogenated La0.3Sr0.7MnO3−δ films show an ultra-high magnetic temperature (>400 K). The efficient modulations of the crystalline structure and functionalities of manganite oxides using the facile hydrogenation process enable practical applications of high-temperature magnetic insulators in spintronic devices. [ABSTRACT FROM AUTHOR]

Aluminum doped zinc oxide (AZO) nanoparticles with different doping concentrations were prepared by a simple one-step hydrothermal synthesis method. The crystal structure, morphology, infrared absorption, infrared emission and microwave loss properties of the AZO nanoparticles were analyzed in detail. With the increase of the aluminum doping concentration, the crystal plane spacing does not change much, while the grain size increases gradually, and the thickness of the flakes and the average size of the particles have no significant change. With the increase of the Al doping concentration, the infrared emissivity of AZO tends to decrease first and then increase, among which the AZO infrared emissivity with Zn-ion ratio of 95:5 is the lowest. The electromagnetic parameters of AZO with a mole doping ratio of 93:7 were carried out at a frequency range of 2–18 GHz, the real part (ε′) and imaginary part (ε″) of the complex permittivity varies between 4.3-4.5 and 0.2–0.4, respectively, the dielectric loss tangent (tan δ) varies between 0.04 and 0.09. [ABSTRACT FROM AUTHOR]

Two kinds of Fe/amorphous carbon (a-C) submicron fibers were prepared by electrospinning using polyvinylpyrrolidone (PVP) and polyacrylonitrile (PAN) as precursor polymer, followed by carbonization under the same conditions. Contributed to the different reaction mechanisms during the annealing process, different phases namely graphite carbon (g-C) and Fe4N formed at the interface between the Fe nanoparticles and the a-C matrix. Electromagnetic absorption properties have shown that the Fe@Fe4N submicron fibers have superior absorption performance than the Fe@g-C ones. The minimal reflection loss (RL) value of the former is − 39.8 dB at 5.4 GHz with the absorber thickness of 5.0 mm, and the effective absorption bandwidth (RL ≤ − 10 dB) can reach 5.0 GHz when the absorber thickness is 2.5 mm. By contrast, the Fe@g-C submicron fibers have little absorption. The attenuation constant, impedance matching coefficient, complex permittivity and complex permeability were investigated in detail. The microstructure and composition were explored various superior tools. The results revealed that the interface Fe4N has a critical role in affecting the magnetic loss and dielectric loss, which brings better impedance matching and relatively low dielectric loss. Therefore, the Fe@Fe4N submicron fibers have excellent microwave absorbing properties. [ABSTRACT FROM AUTHOR]

Two kinds of Fe/C nanofibers were prepared by electrospinning and calcination under the same process conditions. A simple way was used to adjust the size of the Fe nanoparticles by using different spinning solvents. The one was prepared by a mixture of water and anhydrous alcohol as solvents (named as CNF water) and the other by N,N-Dimethylformamide and anhydrous alcohol (named as CNF DMF). Due to the higher solubility to iron salts and larger surface tension of water, CNF water gained a larger size of Fe nanoparticles and average diameter. In addition, the graphite layers wrapped on Fe nanoparticles which were formed during calcination were thinner in CNF water than CNF DMF. These factors endowed CNF water better microwave absorption performance. The results of XRD, SEM, HRTEM, Raman, magnetostatic and electromagnetic properties analysis revealed the influence mechanisms of solvents on the formation, microstructure and properties of Fe/C nanofibers. [ABSTRACT FROM AUTHOR]

Strong demand for affordable clean energy to support applications ranging from conventional energy supply to space propulsion places spotlight on advanced energy generation using photovoltaic and wind power. Yet, the intermittent nature of solar and wind sources drives the search for energy storage solutions that would permit the needed level of resilience and support further growth in the use of renewable sources of power. Hydrogen generation using sunlight is a promising pathway to decouple demand from supply. Herein, we show how exposure to reactive Ar-H 2 , Ar-H 2 -N 2 , and Ar-O 2 plasma environments can notably enhance surface properties of photocatalytic TiO 2 nanosheets used in advanced energy generation systems. Treatment using Ar-H 2 plasmas produced highly hydrogenated, surface-disordered TiO 2 nanosheets with oxygen vacancies, whereas exposure to Ar-H 2 -N 2 plasmas resulted in N doping. Surprisingly, Ar-O 2 plasma treatment did not change surface properties of TiO 2. Optical emission spectroscopy was used to monitor transient species to further understand surface modification in plasma. Direct measurements demonstrated that among thus-produced samples, hydrogenated TiO 2 nanosheets exhibit the highest photocatalytic H 2 -generation activity under visible-light irradiation, which is also greater than the activity of pure, untreated nanosheets. The mechanism of enhancing the visible-light photocatalytic H 2 -generation activity on hydrogenated TiO 2 nanosheets is also proposed. The level of surface disorder and oxygen vacancies plays an important role in enhancing visible-light absorption and reducing the recombination of photogenerated electrons and holes. [ABSTRACT FROM AUTHOR]

The mechanism underlying the crowding effects that assist the condensation process by multivalent cations under confinement is not yet reported. Based on the strong correlation model, Monte Carlo simulation was implemented to detect the crowding effects on DNA condensation within a capsule-like space, and its geometry controlled by the aspect ratio. With the addition of crowders, the condensed conformations confined within the spherical space (aspect ratio is 1) become more compact than those without crowders. The DNA-condensed conformations undergo a transition from the initial random coil structure to toroid structure, followed by the extended rod-like structure, and finally to totally compacted structure. The critical volume fraction corresponding to the transition from the rod-like structure to totally compacted structure pertained to the crowder size proportionally. Moreover, the critical volume fraction corresponding to the phase transition strongly depends on the confinement geometry, the critical volume fraction for the case with constant radius is inversely proportional to the aspect ratio. Conversely, the case with constant cylinder length showed that the critical volume fraction is proportional to the aspect ratio. These phenomena are consistent with their corresponding phase diagram re-expressed in the space of volume fraction and aspect ratio. The effects of confinement geometry and crowder size on the response of DNA condensation to crowding are elucidated and generalized into the space diagram in the space of aspect ratio and crowder size. When the aspect ratio less than 1.6 and the crowder size larger than 2.0 nm or when the aspect ratio ≥ 1.6 and the crowder size larger than the critical d c ∗ , the DNA conformation undergo the transition from the initial random coil structure to toroid structure, followed by totally compacted structure; when the aspect ratio ≥ 1.6 and the crowder size ≤ d c ∗ , the DNA condensed conformations will be condensed further from the totally compacted structure to the extended rod-like structure. Furthermore, the transition from the totally compacted structure to the extended rod-like structure is entirely due to the crowder size and the confinement geometry between the de Gennes and Odijk regimes. [ABSTRACT FROM AUTHOR]