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Controlling the interfacial effect is facing challenges because of the weak interactions between the inorganic and the organic materials. We found that the silane coupling agents with -NH2 groups (e.g., KH550) play a key role as a molecular bridge that links an inorganic silica template with an organic precursor (i.e., pyrrole) in the process of constructing a spherical silica core-polypyrrole shell structure. The molecular bridge is also suitable for inorganic core templates with cube or rod shapes for the construction of different core-shell structures. These template core-polymeric shell structures can be transformed into well-defined hollow carbons after carbonization and template removal. The outer diameter, hollow-core size, and carbon shell thickness of hollow carbon materials (e.g., hollow carbon spheres) could be facilely controlled by changing the template size or the pyrrole amount. We believe that our work will provide a guideline for the preparation of well-orchestrated carbon-based composites and their templated hollow carbons.

Electronic devices with high heat flux are currently facing heat dissipation problems. Heat pipes can be used as efficient heat spreaders to address this critical problem. However, as electronic devices become smaller, the space for heat dissipation is becoming ever so limited; hence, ultrathin heat pipes are desired. This study proposes a biomimetic copper forest wick for an ultrathin heat pipe (UTHP). It is made by a simple one-step electrodeposition process and appears as a natural forest structure with abundant Ω-like grooves. Capillary rise tests with ethanol were performed to characterize the capillary force of the wick structure. Compared to traditional sintered particles, this wick structure has a much higher capillary performance parameter

Recently, a new monolayer Group III–V material, two-dimensional boron phosphide (BP), has shown great potential for energy storage and energy conversion applications. We study the thermoelectric properties of BP monolayer as well as the effect of functionalization by first-principles calculation and Boltzmann transport theory. Combined with a moderate bandgap of 0.90 eV and ultra-high carrier mobility, a large ZT value of 0.255 at 300 K is predicted for two-dimensional BP. While the drastically reduced thermal conductivity in hydrogenated and fluorinated BP is favored for thermoelectric conversion, the decreased carrier mobility has limited the improvement of thermoelectric figure of merit.

The research on graphene-based anode materials for high-performance lithium-ion batteries (LIBs) has been prevalent in recent years. In the present work, carbon-coated SnO

Nanozymes have been widely applied in bio-assays in the field of biotechnology and biomedicines. However, the physicochemical basis of nanozyme catalytic activity remains elusive. To test whether nanozymes exhibit an inactivation effect similar to that of natural enzymes, we used guanidine chloride (GuHCl) to disturb the iron oxide nanozyme (IONzyme) and observed that GuHCl induced IONzyme aggregation and that the peroxidase-like activity of IONzyme significantly decreased in the presence of GuHCl. However, the aggregation appeared to be unrelated to the quick process of inactivation, as GuHCl acted as a reversible inhibitor of IONzyme instead of a solo denaturant. Inhibition kinetic analysis showed that GuHCl binds to IONzyme competitively with H2O2 but non-competitively with tetramethylbenzidine. In addition, electron spin resonance spectroscopy showed that increasing GuHCl level of GuHCl induced a correlated pattern of changes in the activity and the state of the unpaired electrons of the IONzymes. This result indicates that GuHCl probably directly interacts with the iron atoms of IONzyme and affects the electron density of iron, which may then induce IONzyme inactivation. These findings not only contribute to understanding the essence of nanozyme catalytic activity but also suggest a practically feasible method to regulate the catalytic activity of IONzyme.

The influence of the Kerr nonlinearity on the two two-level atoms entanglement is investigated in Jaynes–Cummings model (JCM), so that one of atoms is inside the cavity field and the other atom is outside it. We show that the entanglement of atoms increases with the decrease of the phase decoherence rate or Kerr coefficient, when considering the effect of external environment. Then due to the statistic properties of the anti-bunching effect of photons are related to entanglement, the nonlinear JCM is examined theoretically to analyze the bunching or anti-bunching effect by using the second-order coherence function. We find that the second-order coherence function decreases with the Kerr coefficient. Our results show that the field reflects the stronger bunching effect with the bigger average photon number.

NiO-ZnO/RGO composite was obtained by the annealing of an Ni (OH) 2 -Zn (OH) 2 /RGO precursor, which has been fabricated by in situ ultrasonic agitation. Moreover, the NiO-ZnO nanoflakes are evenly distributed on the RGO sheets based on the scanning electron microscope (SEM) and transmission electron microscope (TEM) characterization results. When the NiO-ZnO/RGO composite was used as an anode material in lithium-ion batteries (LIBs), the electrodes exhibited a high reversible capacity of 1017 mA h/g at a current density of 100 mA/g after 200 cycles and a specific capacity of 458 mA h/g at 500 mA/g even after 400 cycles. The electrode even reached a capacity of 185 mA h/g at a current density of 2000 mA/g. The excellent electrochemical properties of the NiO-ZnO/RGO composite might be attributable to the NiO-ZnO nanoflakes offering rich electrochemical reaction sites and shortening the diffusion length for lithium ion (Li + ), as well as the RGO sheets improving the transfer rates of Li + and electron during the charge-discharge process.

Hypomagnetic fields (HMF), that is, the elimination of the geomagnetic field (GMF), are a risk factor to the health of astronauts in outer space. It has been established that continuous HMF exposure affects cytoskeleton assembly, cell proliferation, embryonic development, and even learning and memory. In addition, although there were some previous studies that focused on the effects of long-term HMF-exposure, so far very limited investigations have been conducted to examine the short-term HMF effect in animals. In this study, we exposed adult male C57BL/6 mice to a 3-axis Helmholtz-coil HMF-simulation system for 72 h and found that short-term HMF-exposure induced a significant increase in anxiety-related behaviors. And our findings provide important information for both psychological intervention and the health care of astronauts. Bioelectromagnetics. 40:27-32, 2019. © 2018 Wiley Periodicals, Inc.

To determine the contributions of elastic strain energy to chemical driving force of uranium hydride growth, an elastic fields model was set up by a spherical hydride particle growing at sub-surface of parent metal, which was used to interpret strain energy influence on the evolution of microstructure and kinetics characteristics of the hydride precipitates. The results showed that strain energy during hydride expansile growth in the matrix is considerably different for the three U materials. When hydride grows, the order of the strain energy value is U-5.7%Nb > U > U-2.5%Nb(mass fraction), which indicated that the U-2.5%Nb alloy is the most susceptible to hydrogen corrosion, followed by U, while U-5.7%Nb is the most resistant to hydrogen corrosion basing on reaction activation theory. Agreement of calculated strain energy with experimental results of hydride growth kinetics showed that the model in this work is correct, in which the large strain energy from volume change during hydride growth plays an important role in determination of growth kinetics. In addition to strain energy calculation, the stress distribution associated with hydride precipitate was used to interpret the interaction between hydride pattern and stress. The study provides quantificational evidences to understand the association of strain energy and stress with hydride of metals, which will lead to novel process opportunities.

Background & aims This study investigates the long-term incidences and predictors of developing hepatocellular carcinoma (HCC), cirrhotic events and mortality in cirrhotic patients receiving entecavir (ETV) therapy. Methods We enrolled 481 nucleos(t)ide analogue-naive chronic hepatitis B (CHB) patients who had compensated cirrhosis upon entry and had received ETV monotherapy for >12 months. Results The 8-year cumulative incidences of developing HCC, cirrhotic events and liver-related mortality were 26.5%, 8.62% and 10.03% respectively. Multivariate analysis revealed that diabetic mellitus (DM), higher fibrosis-4 (FIB-4) and alpha-foetoprotein (AFP) levels at 12 months of treatment, and FIB-4 increase from baseline to 12 months were independent factors of HCC. FIB-4 and AFP levels at 12 months of treatment were also independent factors of cirrhotic events and mortality. FIB-4 cut-off values of 3, 3 and 5 as well as AFP cut-offs of 5, 5, and 9 ng/mL at 12 months of treatment were optimal for predicting HCC, cirrhotic events and mortality during therapy respectively. The FIB-4 and AFP levels at 12 months of treatment were assessed for the combined risk of developing clinical outcomes. The 8-year incidences of HCC, cirrhotic events and liver-related mortality in the subgroups with low FIB-4 and AFP levels were only 5.95%, 1.03% and 2.43% respectively. DM was an independent predictor of HCC and mortality. Conclusion The combination of FIB-4 and AFP levels at 12 months of treatment is a useful marker for predicting the development of HCC, cirrhotic events and mortality in compensated cirrhotic patients with CHB who are receiving ETV therapy.

Fusiform shape MnO/C composite was fabricated for the first time by heat calcining of MnCO3/C precursor, which was produced via a two-step hydrothermal method using glycine, KMnO4 and glucose as reagents. When the composite applied in LIBs as anode materials, the electrodes deliver a reversible capacity as high as 691 mA h g−1 after 120 cycles at a current density of 100 mA g−1 and can retain a stable capacity of 187 mA h g−1 at 1000 mA g−1. Compared with pure MnO particles sample, the enhanced electrochemical performances of MnO/C electrodes were attributed to the carbon layers can effectively improve the transfer rate of electrons and buffer the volume expansion of MnO particles during the charge/discharge process.

Boiling heat transfer is widely used in industry and in daily life and it can be enhanced by micro/nano surface modification. Herein, we study the pool boiling characteristics of the micro nano bi-porous copper surface with optimal cavity size from other researchers and present an efficient way to further enhance its boiling heat transfer performance by wettability modification of enlarging the particle size to lower the surface energy. In this work, two micro nano bi-porous copper surface samples were prepared and compared with conventional surfaces. One is the original micro nano bi-porous copper surface (Sample#O) prepared using the hydrogen bubble template deposition method to form abundant pores in optimal cavity size, and the other one is the modified micro nano bi-porous copper surface (Sample#M) that is modified by applying a low current density on Sample#O for a few minutes. Scanning Electron Microscope (SEM) images show that Sample#M keeps the pore size but enlarges the nano dendrite on the top of pore wall to micro balls. The conducted pool boiling experiments indicate that both micro nano bi-porous copper surfaces have superior heat transfer coefficients than the plain copper surface, and the high-speed camera shows that the micro nano bi-porous copper surfaces have shorter bubble growth periods than those surfaces with pure nano structure or pure micro structure. At a heat flux of 90 W cm−2, the heat transfer coefficient of Sample#O is 13 W cm−2 K−1, which is 2.8 times over that of the plain surface. Compared to Sample#O, Sample#M can further enhance the pool boiling heat transfer. At the same heat flux of about 90 W cm−2, the heat transfer coefficient of Sample#M is 23 W cm−2 K−1, which is 1.7 times over that of Sample#O and 4.8 times over that of the plain surface. The heat transfer coefficient of Sample#M can be as high as 30 W cm−2 K−1 when it reaches the CHF. High-speed camera images show that highest bubble growth period for Sample#M is just less than 20 ms, which is shorter than that of Sample#O having a value in between 20 ms and 40 ms. It confirms that Sample#M after wettability modification has a lower interface energy which can accelerate the bubbles departure, and has an even more superior heat transfer performance than Sample#O.

In this review, an attempt was made to introduce the traditional concepts and materials in thermoelectric application and the recent development in searching high-performance thermoelectric materials. Due to the use of nanostructural engineering, thermoelectric materials with a high figure of merit are designed, leading to their blooming application in the energy field. One dimensional nanotubes and nanoribbons, two-dimensional planner structures, nanocomposites, and heterostructures were summarized. In addition, the state-of-the-art theoretical calculation in the prediction of thermoelectric materials was also reviewed, including the molecular dynamics (MD), Boltzmann transport equation, and non-equilibrium Green’s function. The combination of experimental fabrication and first-principles prediction significantly promotes the discovery of new promising candidates in the thermoelectric field.

The U–Ti binary system was investigated via experimental measurements and thermodynamic modeling. In order to clarify the disputed phase equilibria of the U–Ti system, 11 alloys with different contents of Ti were prepared by arc melting. The investigated Ti content covers the U-rich portion within the composition range from 1 at.% Ti to 33.3 at.% Ti. All samples were annealed at the temperatures of 640, 720 and 730 °C, and then analyzed by optical microscopy, X-ray diffraction, scanning electron microscopy, energy dispersive X-ray spectroscopy and differential scanning calorimeter. The phase equilibria associated with γ(U,Ti), αU, βU, and δ-U2Ti were experimentally determined in detail. The reaction temperature and composition of the invariant reaction γ(U,Ti) → βU + δ-U2Ti were precisely determined, and the invariant reaction temperature of the reaction βU→ αU + δ-U2Ti was updated. The solid solubility of Ti in αU at low temperatures was also revised by experiments. The temperature and the enthalpy of transition δ-U2Ti to γ(U,Ti) were newly measured by the differential scanning calorimeter. Finally, a set of self-consistent thermodynamic parameters were obtained by taking into account the present experimental findings and reliable literature data using CALPHAD (Calculation of phase diagrams) technique, and all calculated results are in good agreement with the experimental ones.