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Electrochemical nitrate reduction to ammonia (NRA) is considered a promising strategy for environmental protection and energy saving because it can simultaneously achieve nitrate wastewater treatment and ammonia synthesis. However, currently, this method suffers from the lack of efficient electrocatalysts. In this work, through a “killing two birds with one stone” strategy, a catalyst, TiO2@C/Fe2O3nanosheet arrays (NSAs), was fabricated by introducing hydrothermal carbon (HTC), which not only accelerates the charge transfer due to its good conductivity but also provides abundant oxygen vacancies owing to its nice reducibility, finally improving the NRA performance. Compared with TiO2/Fe2O3NSAs, TiO2@C/Fe2O3exhibited higher NRA performance with a nitrate conversion of 88.6%, ammonia selectivity of 83.4%, Faradaic efficiency of 85.3%, and ammonia yield of 0.2176 mmol h−1cm−2. Moreover, the retention of high activity in nine cyclic experiments confirmed the outstanding stability of TiO2@C/Fe2O3. Furthermore, the possible NRA reaction pathway was derived from the results of electrochemical quasi in situelectron spin resonance experiments, electrochemical in situattenuated total reflection Fourier transform infrared measurement and online differential electrochemical mass spectrometry. This feasible strategy of introducing an HTC interlayer may open new avenues for developing novel NRA electrocatalysts.

Platelets are affected by many factors, such as infectious or aseptic inflammation, and different inflammatory states may induce either thrombocytopenia or thrombocytosis. Tumor necrosis factor α (TNFα) is an important inflammatory cytokine that has been shown to affect the activity of hematopoietic stem cells. However, its role in megakaryocyte (MK) development and platelet production remains largely unknown. This study aimed to investigate the effects of TNFα on MK and platelet generation. The ex vivostudy with human CD34+cells demonstrated that TNFα differentially modulated commitment toward the MK lineage. Specifically, a low concentration of 0.5 ng/ml TNFα promoted MK maturation, proplatelet formation, and platelet production, whereas a high concentration of 10 ng/ml or more TNFα exhibited a substantial inhibitory effect on MK and platelet production. The distinct effect of TNFα on MKs was mainly dependent on TNFα receptor 1. TNFα differentially regulated the MAPK–ERK1/2 signaling pathway and the cytoskeletal proteins cofilin and MLC2. The in vivostudy with Balb/c mice indicated that low‐dose or high‐dose TNFα administration differentially affected short‐term platelet recovery after bone marrow transplantation. Our study revealed distinct roles for TNFα in megakaryopoiesis and thrombopoiesis and may provide new insights regarding the treatment for platelet disorders.

Platelets are affected by many factors, such as infectious or aseptic inflammation, and different inflammatory states may induce either thrombocytopenia or thrombocytosis. Tumor necrosis factor α (TNFα) is an important inflammatory cytokine that has been shown to affect the activity of hematopoietic stem cells. However, its role in megakaryocyte (MK) development and platelet production remains largely unknown. This study aimed to investigate the effects of TNFα on MK and platelet generation.

Food-related functional substances with biological activity serve as a crucial material foundation for achieving precision nutrition, which has gained increasing attraction in regulating physiological functions, preventing chronic diseases, and maintaining human health. Nutritional substances typically include bioactive proteins, peptides, polysaccharides, polyphenols, functional lipids, carotenoids, probiotics, vitamins, saponins, and terpenes. These functional substances play an essential role in precise nutrition. This chapter introduces and summarizes typical functional substances to demonstrate the challenges in precision nutrition for their stability, solubility, and bioavailability. The current status of delivery systems of functional substances is described to give an insight into the development of desirable characteristics, such as food grade status, high loading capacity, site targeting, and controlled release capacity. Finally, the applications of food-borne delivery systems of functional substances for precision nutrition are emphasized to meet the requirement for precision nutrition during nutritional intervention for chronic diseases.

High-performance dielectric nanomaterials have received increasing attention due to their important applications in the field of energy storage. Among various dielectric materials, polymer nanocomposite is one of the most promising candidates. However, the problems of environmental pollution caused by polymer-based dielectric materials have been extensively studied in recent years, which need to be solved urgently, leading to the search for new biodegradable dielectric materials. Herein, we report composite materials based on biodegradable and renewable chitin and molybdenum disulfide (MoS2) nanosheets for the first time. The MoS2nanosheets were first fabricated by glycerol/urea system and then KOH/urea aqueous solution was used to directly dissolve chitin at low temperature together with the dispersion of the MoS2nanosheets in a simple green process. The two-dimensional MoS2nanosheets possess high polarization strength, and a large specific surface area can enhance the interfacial polarization with chitin; meanwhile, it can serve as a charge breakdown barrier to hinder the propagation of electrical tree branches. The results also show that the dielectric constant and breakdown strength of the chitin/MoS2nanocomposites were increased, while the dielectric loss remained low. When the MoS2content was 5 wt %, the charge and discharge efficiencies of the composite film were more than 80%, and the breakdown strength also reached 350 MV m–1, thus resulting in a high discharge energy density of 4.91 J cm–3, which was more than twice of the neat chitin (2.17 J cm–3). Furthermore, the nanocomposite films exhibited good thermal stability. Therefore, these chitin-based nanocomposite films are promising as high-performance biomass-based dielectric capacitors.

We report the light-induced modification of catalytic selectivity for photoelectrochemical CO2reduction in aqueous media using copper (Cu) nanoparticles dispersed onto p-type nickel oxide (p-NiO) photocathodes. Optical excitation of Cu nanoparticles generates hot electrons available for driving CO2reduction on the Cu surface, while charge separation is accomplished by hot-hole injection from the Cu nanoparticles into the underlying p-NiO support. Photoelectrochemical studies demonstrate that optical excitation of plasmonic Cu/p-NiO photocathodes imparts increased selectivity for CO2reduction over hydrogen evolution in aqueous electrolytes. Specifically, we observed that plasmon-driven CO2reduction increased the production of carbon monoxide and formate, while simultaneously reducing the evolution of hydrogen. Our results demonstrate an optical route toward steering the selectivity of artificial photosynthetic systems with plasmon-driven photocathodes for photoelectrochemical CO2reduction in aqueous media.

Electrochemical reduction of CO2to CO offers a promising strategy for regulating the global carbon cycle and providing feedstock for the chemical industry. Understanding the origin that determines the faradaic efficiency (FE) of reduction of CO2to CO is critical for developing a highly efficient electrocatalyst. Here, by constructing a single-atom Ni catalyst on nitrogen-doped winged carbon nanofiber (NiSA-NWC), we find that the single-atom Ni catalyst possesses the maximum CO FE of over 95% at −1.6 V vs Ag/AgCl, which is about 30% higher than the standard Ni nanoparticles on the same support. The Tafel analysis reveals that the single-atom Ni catalyst has a preferred reduction of CO2to CO and a slower rate for the hydrogen evolution reaction. We propose that the domination of singular Ni1+electronic states and limited hydrogen atom adsorption sites on the single-atom Ni catalyst lead to the observed high FE for CO2reduction to CO.

In order to evaluate the movements characteristics of aggregate particles in asphalt mixture under loading and temperature effects and to study the heterogeneity of asphalt mixture, rutting tests were conducted. Firstly, AC-20, AC-25, SMA-20 and SMA-25 specimens with the baseline labeled on sections were selected to conduct rutting tests. Then the section images at different loading times and different temperature were handled by digital image processing to study the aggregate particle movement behavior by means of aggregate particle movement parameters. Finally, the asphalt mixture heterogeneity was analyzed by the defined heterogeneity area and homogeneity area. The results show that the longitudinal displacement of aggregates is significantly greater than the lateral displacement of aggregates under the standard axle load. The aggregate particles irregular movement area for gap-graded asphalt mixture is greater than dense-graded asphalt mixture at the same temperature and loading. And the temperature or loading increasing can lead to the increase of the heterogeneity area.

Industrial scale catalytic chemical synthesis demands both high reaction rates and high product yields. In exothermic chemical reactions, these conflicting objectives require a complex balance of optimized catalysts, high temperatures, high pressures, and multiple recycling steps, as in the energy-intensive Haber–Bosch process for ammonia synthesis. Here we report that illumination of a conventional ruthenium-based catalyst produces ammonia with high reaction rates and high conversion yields. Indeed, using continuous wave light-emitting diodes that simulate concentrated solar illumination, ammonia is copiously produced without any external heating or elevated pressures. The possibility of nonthermal plasmonic effects are excluded by carefully comparing the catalytic activity under direct and indirect illumination. Instead, thermal gradients, created and controlled by photothermal heating of the illuminated catalyst surface, are shown to be responsible for the high reaction rates and conversion yields. This nonisothermal environment enhances both by balancing the conflicting requirements of kinetics and thermodynamics, heralding the use of optically controlled thermal gradients as a universal, scalable strategy for the catalysis of many exothermic chemical reactions.

The CDEX-10 experiment searches for light weakly interacting massive particles, a form of dark matter, at the China Jinping Underground Laboratory, where approximately 10 kg of germanium detectors are arranged in an array and immersed in liquid nitrogen. Herein, we report on the experimental apparatus, detector characterization, and spectrum analysis of one prototype detector. Owing to the higher rise-time resolution of the CDEX-10 prototype detector as compared with CDEX-1B, we identified the origin of an observed category of extremely fast events. For data analysis of the CDEX-10 prototype detector, we introduced and applied an improved bulk/surface event discrimination method. The results of the new method were compared to those of the CDEX-1B spectrum. Both sets of results showed good consistency in the 0–12 keVee energy range, except for the 8.0 keV K-shell X-ray peak from the external copper.

Enhancing the electrocatalytic activity of low-cost transition-metal oxides for oxygen reduction reaction (ORR) is a crucial challenge for extensive application of fuel cells. A promising approach demonstrated previously is the formation of catalysts with mixed valent metal active sites. Because catalysis happens primarily on the surface of the catalyst, we hypothesize that creating such active sites only on the surface will be an effective strategy for improving the catalytic activities. Here, we present a partial oxidation approach that grows δ-MnO2nanoflakes on the surface of octahedron Mn3O4nanocrystals for increasing their ORR activity. The δ-MnO2/Mn3O4nanocomposite exhibits significantly improved ORR activity with a half-wave potential of 0.75 V versus reversible hydrogen electrode, which is ∼110 and ∼90 mV lower than those of the Mn3O4nanocrystal and δ-MnO2nanoflakes in their pure forms, respectively. The electrochemical impedance spectroscopy reveals that the δ-MnO2/Mn3O4nanocomposite possesses a lower ORR charge transfer resistance than either component alone. We propose that the reason for such significant improvement in catalytic activities is due to the tuning of the position of δ-MnO2nanoflake d-band center by the Mn3O4nanocrystal which can effectively facilitate the electron transfer between the active sites and adsorbed oxygen molecules. This work illustrates a facile pathway to improve catalytic activity of mixed valence metal oxides.

We report the first results on 76Ge neutrinoless double beta decay from stage one of the China dark-matter experiment (CDEX). A p-type point-contact high-purity germanium detector with a mass of 994 g has been installed to detect neutrinoless double beta decay events, as well as to directly detect dark matter particles. An exposure of 304 kg d has been analyzed over a wide spectral band from 500 keV to 3 MeV. The average event rate obtained was about 0.012 counts per keV per kg per day over the 2.039 MeV energy range. The half-life of 76Ge neutrinoless double beta decay derived based on this result is T1/20ν>6.4×1022yr (90% C.L.). An upper limit on the effective Majorana-neutrino mass of 5.0 eV has been achieved.

•Identification of patients with high risk for chronic ankle instability (CAI) is crucial for more effective and efficient treatment of acute lateral ankle sprain (LAS).•For patients who had at least 1 positive clinical finding in the 10-meter walk test, the anterior drawer test, or the inversion tilt test, magnetic resonance imaging (MRI) scans were helpful in predicting CAI after first-episode LAS.•Age, body mass index, posterior talofibular injury, large talus bone marrow lesion, and grade-2 tibiotalar joint effusion were 5 prognostic factors that MRI scanning used to predict CAI after first-episode LAS.

In this paper, the filter technique proposed for solving optimization problem is applied to solve variational inequality problem. It avoids the use of a merit function which often arises in solving VI problems by an optimization method. The presented method is a tri-dimensional filter sequential quadratic programming method. Specially, a differentiable quadratic function is employed as the objective function in implementing the optimality measure in filter components. Under some mild conditions, global convergent is derived. Numerical results show efficiency of this method.

Abstract: It is interesting to study the characteristics of the whole family of B c which contains two different heavy flavors. LHC and the proposed Z 0 factory provide an opportunity because a large database of the B c family will be achieved. B c and its excited states can be identified via their decay modes. As suggested by experimentalists, B* c (ns) → B c + γ is not easy to be clearly measured, instead, the trajectories of π + and π − occurring in the decay of B c (ns) → B c (ms) + π + π − ( n > m) can be unambiguously identified, thus the measurement seems easier and more reliable; therefore this mode is more favorable at the early running stage of LHCb and the proposed Z 0 factory. In this work, we calculate the rate of B c (ns) → B c (ms) + π + π − in terms of the QCD multipole-expansion and the numerical results indicate that the experimental measurements with the luminosity of LHC and Z 0 factory are feasible.

Abstract: The magnetic dipole transitions between the vector mesons B* c and their relevant pseudoscalar mesons B c (B c , B* c , B c (2S), B* c (2S), B c (3S), B* c (3S) etc., the binding states of (c $$ \bar b $$) system) of the B c family are interesting. The ‘hyperfine’ splitting due to spin-spin interaction is an important topic for understanding the spin-spin interaction and the spectrum of the the (c $$ \bar b $$) binding system. The knowledge about the magnetic dipole transitions is also very useful for identifying the vector boson B* c mesons experimentally, whose masses are just slightly above the masses of their relevant pseudoscalar mesons B c . Considering the possibility to observe the vector mesons via the transitions at Z 0 factory and the potential use of the theoretical estimate on the transitions, we fucus our efforts on calculating the magnetic dipole transitions, i.e. a precise calculation of the rates for the transitions such as decays B* c → B c γ and B* c → B c e + e −, and particularly work in the Bethe-Salpeter framework. As a typical example, we carefully investigate the dependence of the rate Γ(B* c → B c γ) on the mass difference $$ \Delta M = M_{B_c^* } - M_{B_c } $$.

Abstract: We analyze the cross section of e + e − → τ +µ− within the frameworks of SM and its Z′ extension. The theoretical prediction of the SM on the total cross section is suppressed by the tiny neutrino masses. On the other hand, the contributions from Z′ to the cross section are enhanced drastically because of the tree level FCNC couplings among Z′ and leptons.

Systematically, we study the long-range contribution to the mixing effects based on the potential model while the QCD correction in Hamiltonian being taken into account. We have found that the long-distance effects are important to and , but . The QCD correction causes a change to the results, enhances the mixing, for , by a factor of 1.3, whereas for it is a suppression of about 0.7. The absorptive parts which give rise to have also been discussed and the diquark-intermediate-state contributions to D and B systems are included.

Ammonia has been recognized as a promising hydrogen mediator as it reduces the expense of the long-range transportation of hydrogen. However, methods to extract hydrogen from ammonia require improvements to decrease the overall cost. Ammonia electrolysis provides a convenient method to attain a low-cost hydrogen production. Here, we report that nickel-cobalt nitride nanosheets can achieve high electrocatalytic activity for the ammonia oxidation reaction (AOR) in non-aqueous solutions. The AOR onset overpotential of NiCo2N nanosheets is 0.55 V, which is about 0.25 V lower than that of the Pt/C electrocatalyst. Our ultraviolet–visible and mass spectroscopy studies reveal that NiCo2N nanosheets bypass the formation of the soluble metal-amine complex and preferentially oxidize ammonia to environmentally friendly diatomic nitrogen with a Faradic efficiency of over 90%. Theoretical simulation further indicates that the downshift of metal d-band on NiCo2N nanosheets surface helps retain a long-lasting electrocatalytic activity. Overall, this work introduces a new family of active and stable electrocatalysts for AOR that is based on earth-abundant transition metals, heralding the feasibility of using ammonia as a hydrogen mediator in hydrogen-based applications.

The local pH near the surface of a CO2reduction electrocatalyst strongly impacts catalytic selectivity and activity. Here, confocal fluorescence microscopy was used to map the electrolyte pH near a copper gas diffusion electrode during CO2reduction with micron spatial resolution in three dimensions. We observed that the local pH increased from pH 6.8 to greater than pH 10 as the current density was increased from 0 to 28 mA/cm2in a 100 mM KHCO3electrolyte. Variations in the pH across the surface indicate areas of locally increased activity. Within deep trenches of the active layer, the local pH increases as trench width decreases. Computational models confirm these experimental results and also showed that the catalyst found within narrow trenches is more active than that found at the surface of the electrode. This study suggests that the overpotential required to perform selective CO2reduction can be reduced by increasing the density of narrow trench regions in the microporous layer.