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Background: Nanowires (NWs) have received extensive attention as the candidate materials for transparent conductive films (TCFs) in recent years. To date, the aligned nanowire (NW)- based TCFs with the same arrangement direction have shown superior characteristics to their random counterparts in applications. Objective: To fully develop the potential of NW TCFs in devices and provide inspiration for the development of subsequent NW alignment processes, this review summarizes state-of-the-art alignment techniques and emphasizes their mechanisms in detail from multiple perspectives. Methods: According to the mechanism of NW alignment, this review divides these techniques into seven categories, i.e., the assisted assembly of fluid flow, meniscus, pressure, template, electromagnetic field, contact and strain, and analyzes the characteristics of these techniques. Moreover, by briefly enumerating the applications of aligned NW films in solar cells, organic light-emitting diodes, and touch screens, the superiority of aligned NW films over random NW films is also addressed. Results: Contact-assisted assembly exhibits the best arrangement effect, reaching a 98.6% alignment degree within ±1°. Under the same conditions, shorter NWs show better alignment in several cases. The combination of various assembly techniques is also an effective means to improve the alignment effect. Conclusion: There is still room for improvement in the precise control of NW position, density, and orientation in a simple, efficient and compatible process. Therefore, follow-up research work is needed to conquer these problems. Moreover, a process that can realize NWs’ alignment and film patterning simultaneously is also a desirable scheme for fabricating personalized devices.

Accurate calculation of protein-protein binding free energy is of great importance in biological and medical science, yet it remains a hugely challenging problem. In this work, we develop a new strategy in which a screened electrostatic energy (i.e., adding an exponential damping factor to the Coulombic interaction energy) is used within the framework of the molecular mechanics/Poisson-Boltzmann surface area (MM/PBSA) method. Our results show that the Pearson correlation coefficient in the modified MM/PBSA is over 0.70, which is much better than that in the standard MM/PBSA, especially in the Amber14SB force field. In particular, the performance of the standard MM/PBSA is very poor in a system where the proteins carry like charges. Moreover, we also calculated the mean absolute error (MAE) between the calculated and experimental ΔG values and found that the MAE in the modified MM/PBSA was indeed much smaller than that in the standard MM/PBSA. Furthermore, the effect of the dielectric constant of the proteins and the salt conditions on the results was also investigated. The present study highlights the potential power of the modified MM/PBSA for accurately predicting the binding energy in highly charged biosystems.

Nanosecond-level transient electromagnetic disturbance (TED), including very fast transient overvoltage caused by operation of disconnectors, high-altitude electromagnetic pulse, and many other fast transients may interfere or even damage the electrical equipment. As one of the main overvoltage protective equipment, the protective performance of metal-oxide surge arresters (MOAs) under nanosecond-level TED should be investigated and then compared with that under microsecond-level TED, especially the lightning impulse. Based on a testing platform containing a 400-kV pulse generator with adjustable rise time from 5 to 100 ns, the behaviors of nonlinearity, fast impulse response, and converting impedances of three types of 10-kV MOAs under TED with different rise time were explored experimentally in this article. The peak residual voltages of 10-kV MOAs under TED with the rise time of 5 ns at 5 kA are 50.2–60.7% higher than those under the lightning impulse. The rise time of TED has significant influence on the peak voltage and impedance converting behaviors of MOAs. A circuit model of 10-kV MOAs under nanosecond-level TED is built and validated by experimental results, which can be applied in insulation coordination and design of protective devices against TED.

To solve the problem of unstable sealing in the sealing section of a gassy, soft coal seam, a seal reinforcement material for gas extraction boreholes was developed, which was mainly made of ordinary Portland cement and blended with additives such as aluminium powder, quicklime, and gypsum. Firstly, in order to obtain the necessary expansion and compressive strength of reinforcement material, key factors affecting the material properties were determined. Key factors affecting the expansion properties and compressive strength of reinforcing materials were investigated by a single-factor test. Moreover, according to the central combination (Box–Behnken) experimental principle and response surface analysis (RSA), the interactions of various factors on the expansion and compressive strength were determined, and the optimal experimental conditions were acquired. The experimental results indicated that the optimum ratio of the material was 2% for gypsum and 0.52% for aluminium powder and quicklime at the experimental temperature of 20°C, and the ratio of water to material was 0.6. Finally, in the N1103 working face of No. 3 coal seam of Yuwu coal mine, Luan Group, China, the sealing property of the reinforcement material was validated, and the problem of hole collapse at the borehole orifice was solved (resulting in a gas concentration 2.48 times that measured before borehole reinforcement), and the gas drainage effect was enhanced.

The annual output of domestic waste has exceeded 400 million tons in China since 2016, which causes an urgent demand on harmless disposal in the current rapid process of urbanization. Compared with traditional disposal means (e.g. incineration and landfill), co-processing with cement production seems to be a better chose to meet the requirements of domestic waste treatment (i.e. harmless, volume reduction, waste utilization). However, co-processing technology also has some negative impact (e.g. extra energy consumption for pretreatment of domestic waste), so the environmental feasibility of domestic waste co-processing in cement kiln should be verified. In this paper, the influences caused by domestic waste co-processing on the cement clinker products including resource/energy consumption, as well as the pollutant emissions were quantify based on the investigation of typical plants in China. Moreover, the environment impact between landfill treatment and co-processing scenario were compared using life cycle assessment (LCA) method. The result shows that the energy consumption and CO2 emission per ton cement clinker production increased by 3.6% and 0.8% after co-process domestic waste, respectively. Furthermore, compared with sanitary landfill treatment, the co-processing in cement kiln will increase the impact of FFP, but reduce GWP and HTP impacts, especially significantly decrease the impact of LOP and SOP, bring in a good beneficial on material saving and energy saving.

Quinones can undergo thermodynamically reversible proton-coupled electron transfer reactions and are being applied as electroactive compounds in aqueous organic batteries. However, the electrochemi...

Three-point bending tests are employed to research the damage behavior of glass fiber epoxy composites repaired by patch embedded with ZnO whiskers. In particular, the role of ZnO whiskers is discu...

Electrocatalysts in acidic media face the issues of inactivation and degradation with complex thermodynamic processes. A density functional theory (DFT) calculation is performed to investigate the galvanic and pitting etching processes of metal@Pt (M@Pt) core-shell nanoparticles (12 transition elements are selected to replace the core atoms). The dissolution process with atomic etching follows the dissolution potential site-dependence phenomena, and the dissolution potential of the Pt shell exhibits a negative linear correlation with the average d-band center of the Pt shell. We have found that the specific shape effect, core-shell contact area and period effect all affect the potential difference at each step in the dissolution process. Meanwhile, the core atom segregation reduces the dissolution potential to form defects on the outermost shell, which is the driving force of halogen-pitting. By analyzing the 12 core elements and M@Pt nanoparticles of three specific shapes, Ir@Pt nanoparticles with a TCO-structure exhibit a high initial potential in multistep dissolution process throughout the galvanic etching process and good performance with respect to pitting corrosion and are strong candidates for nanoparticle catalysts.

Magnesium chloride hexahydrate, as a phase change materials, is investigated usually to store solar energy. Here, the effect of hydrophilic modification of expanded graphite with Triton X-100 on the thermophysical properties of magnesium chloride hexahydrate was presented. Differential scanning calorimetry, scanning electron microscope, Fourier transform infrared spectroscopy and thermal gravimetric analysis, etc., were used. The magnesium chloride hexahydrate/hydrophilic expanded graphite composite phase change materials had more excellent thermal characteristics than magnesium chloride hexahydrate/expanded graphite composite phase change materials and pure magnesium chloride hexahydrate. The results showed that hydrophilic expanded graphite could better promote the endothermic and exothermic properties of magnesium chloride hexahydrate. After hydrophilic modification, the composites with higher melting enthalpy, better thermal conductivity and less supercooling were obtained. And the leakage test demonstrated that the hydrophilic modification of expanded graphite can reduce the leakage of magnesium chloride hexahydrate powerfully.

This paper presents a label-free method for distinguishing lung adenocarcinoma cells from normal cells based on the confocal Raman spectra and a support vector machine. First, confocal Raman spectra of 242 lung adenocarcinoma cell samples and 231 normal cell samples are measured, followed by extracting the peak position and the intensity features. Furthermore, a multivariate correlation analysis of spectra features is performed to prevent the cross-sensitivity errors and to obtain a higher accuracy. Then, support vector machines with two different kernels, i.e., a polynomial function and a Gaussian radial basis function, are explored for the classification of all the samples. Benefiting from both the Raman spectra difference and the support vector machine, an accuracy of 97.5%, a sensitivity of 100%, and a specificity of 95% are achieved. The results indicate that this method is effective in identifying cancerous cells. Moreover, further work also demonstrates that the accuracy can reach 85%, even in the case of a small number of training samples (i.e., less than 100), so this method has great potential in the noninvasive detection of lung adenocarcinoma and can be easily applied to other fields of biophotonics in the future.

In this paper, the nonlinear free vibration responses of functionally graded nanocomposite fluid-conveying tube reinforced by single-walled carbon nanotubes (SWNTs) in thermal environment is investigated. The SWCNTs gradient distributed in the thickness direction of the tube forms different reinforcement patterns. The materials properties of the functionally graded carbon nanotube-reinforced composites (FG-CNTRC) are estimated by rule of mixture. A higher-order shear deformation theory and Hamilton’s variational principle are employed to derive the motion equations incorporating the thermal and fluid effects. A two-step perturbation method is implemented to obtain the closed-form asymptotic solution for these nonlinear partial differential equations. The nonlinear frequency under several patterns of reinforcement are presented and discussed. We conducted a series of studies aimed at revealing the effects of the flow velocity, environment temperature, geometrical ratios and carbon nanotube volume fraction on the nature frequency.

We demonstrate a carbon capture system based on pH swing cycles driven through proton-coupled electron transfer of sodium (3,3′-(phenazine-2,3-diylbis(oxy))bis(propane-1-sulfonate)) (DSPZ) molecules. Electrochemical reduction of DSPZ causes an increase of hydroxide concentration, which absorbs CO2; subsequent electrochemical oxidation of the reduced DSPZ consumes the hydroxide, causing CO2 outgassing. The measured electrical work of separating CO2 from a binary mixture with N2, at CO2 inlet partial pressures ranging from 0.1 to 0.5 bar, and releasing to a pure CO2 exit stream at 1.0 bar, was measured for electrical current densities of 20–150 mA cm−2. The work for separating CO2 from a 0.1 bar inlet and concentrating into a 1 bar exit is 61.3 kJ molCO2−1 at a current density of 20 mA cm−2. Depending on the initial composition of the electrolyte, the molar cycle work for capture from 0.4 mbar extrapolates to 121–237 kJ molCO2−1 at 20 mA cm−2. We also introduce an electrochemical rebalancing method that extends cell lifetime by recovering the initial electrolyte composition after it is perturbed by side reactions. We discuss the implications of these results for future low-energy electrochemical carbon capture devices.

The hydrogen-induced delayed cracking (HIDC) behaviors of two types of 1500 MPa grade hot stamping steels (HSSs) have been investigated by the method of slow strain rate tensile test and hydrogen permeation, where one is manufactured by compact strip production (CSP) process which is a revolution to the traditional HSS and the other by the traditional cold rolling process. The results show that the performance of HSS produced by CSP is superior to that of the traditional HSS, due to lower hydrogen embrittlement index, lower hydrogen diffusion coefficient and lower hydrogen content. It has been found that HIDC behavior is closely associated with inclusions. The inclusions of HSS produced by CSP are mainly spherical Al–Ca–O and CaS, while the inclusions in the traditional HSS are TiN + Al2O3 + MnS with sharp edges and corners. Based on these results, the influence of composition, shape and distribution of inclusions in HSS on HIDC and the mechanism of HIDC from the perspective of inclusions were analyzed and discussed.

Even with SiC power MOSFETs released into the commercial market, the threshold voltage instability caused by near interface states is still an attracting issue, which is a major obstacle to further improving the device performance. In this paper, the effects of temperature storage on the threshold voltage stability of n-channel 4H-SiC VDMOSFET are studied. It is found that the capture of hole traps is dominant during the long-term temperature storage at 425 K, causing a considerable negative shift of threshold voltage. In view of the influence of temperature storage, the positive and negative drift trends of threshold voltage slow down during the gate-bias stress measurement. And the ∆VTH, the difference between the threshold voltages recorded after positive and negative gate-bias stress in the same duration, also grows slowly with the increasing stress duration. Finally, some suggestions for improving the threshold reliability of n-channel SiC VDMOSFETs are presented.

Due to the similar collagen composition and closely physiological relationship with soft connective tissues, demineralized bone matrices (DBMs) were used to repair the injured tendon or ligament. However, the osteoinductivity of DBMs would be a huge barrier of these applications. Hydrogen peroxide (H2 O2 ) has been proved to reduce the osteoinductivity of DBMs. Nevertheless, the biological properties of H2 O2 -treated DBMs have not been evaluated completely, while the potential mechanism of H2 O2 compromising osteoinductivity is also unclear. Hence, the purpose of this study was to characterize the biological properties of H2 O2 -treated DBMs and search for the proof that H2 O2 could compromise osteoinductivity of DBMs. Decellularized and demineralized bone matrices (DCDBMs) were washed by 3% H2 O2 for 12 h to fabricate the H2 O2 -treated DCDBMs (HPTBMs). Similar biological properties including collagen, biomechanics, and biocompatibility were observed between DCDBMs and HPTBMs. The immunohistochemistry staining of bone morphogenetic protein 2 (BMP-2) was negative in HPTBMs. Furthermore, HPTBMs exhibited significantly reduced osteoinductivity both in vitro and in vivo. Taken together, these findings suggest that the BMP-2 in DCDBMs could be the target of H2 O2 . HPTBMs could be expected to be used as a promising scaffold for tissue engineering. © 2019 Wiley Periodicals, Inc. J Biomed Mater Res Part A, 2019.

Modifying the surface properties of energetic materials has theoretical and practical significance in the field of their application. In this paper, irregular cyclotetramethylene tetranitramine (HM...

The stearic acid (SA) – hexanamide (HA) binary mixtures were prepared, and the phase diagram and Tammann plot were constructed. The differential scanning calorimetry results indicated that a eutectic composition formed by 46.2 mol% SA and 53.8 mol% HA melted at the temperature of 331.15 K with a latent heat of 176.62 J·g−1. Fourier transform infrared spectroscopy and X-ray diffraction results revealed that SA and HA were just physical mixture. The results of thermogravimetric analysis and 100 thermal cycles test respectively manifested that eutectic mixture had good thermal stability and reliability. Therefore, eutectic mixture is promising for thermal energy storage application.

A series of stearic acid (SA)/benzamide (BA) binary mixtures were prepared and demonstrated, and then the phase diagram and Tammann plot were established. The results showed that the molar fraction of SA in SA-BA eutectic mixture was 0.757. The eutectic mixture melted at 339.05 K with 200.15 J·g−1 latent heat. Expanded graphite (EG) was added to eutectic mixture to form composite phase change materials (PCMs) owing to the eutectic mixture has low thermal conductivity. It was found that the binary mixture and EG had good chemical compatibility, and the thermal conductivity of the composite with 12 wt% EG was significant increased by 12.30 times compared to eutectic mixture. Besides, the phase change properties of eutectic mixture/12 wt% EG composite phase change material (PCM) had a little change after 100 thermal cycles, and had negligible mass loss after leakage test. These results demonstrated that the composite PCM had good thermal reliability and stability. Based on the above results, the composite PCM has great potential in thermal energy storage application.

Based on the semiconductor transport theory, a computational model for the axial conductivity of one-dimensional nanowires is established. Utilizing the band structure data from the first principles, the conductivity, carrier concentration and mobility of phosphorus doped SiCNWs (P-SiCNWs) before and after passivation were numerically simulated. The results show that hydrogen passivation can greatly improve the conductivity of P-SiCNWs, above room temperature, the conductivity is improved nearly two orders of magnitude, and enhance the thermal stability. The reason is that hydrogen passivation saturates the surface dangling bonds, leading to the disappearance of discrete impurity band of P-SiCNWs. In addition, the surface dangling bonds lead to greater thermal instability of conductivity under room temperature, but this thermal instability decrease rapidly with the increase of temperature. The study will help us to understand the transport properties of low dimensional semiconductors, and provide theoretical support for the research of nano electronic and optoelectronic devices.

An effect experiment of a 10 kV oil-immersed transformer injected by the nanosecond pulse is conduced in this paper. To carry out the experiment, an equivalent 10 kV transmission line (TL) platform is constructed where the characteristic impedance of TL is designed as practical value. By injecting the nanosecond pulse with increasing amplitude, the injected current and response current as well as the injected voltage are measured simultaneously. Based on the measured data, the effect of transformer is analyzed.

The biomechanical characteristics of tendon grafts is essential for tendon reconstructive surgery due to its great role in providing a good mechanical environment for tendon healing and regeneration. In our previous studies, the decellularized tendon slices (DTSs) and decellularized bovine tendon sheets (DBTSs) scaffolds were successfully developed. However, the influence of the integrity of tendinous membrane (endotenon and epitenon) and fascicle on biomechanical characteristics of these two scaffolds was not investigated. In this study, we assessed the integrity of tendinous membrane and fascicle of the tendon derived scaffolds and its effect on the biomechanical characteristics. The results of histological staining indicated that the DBTSs had complete endotenon and epitenon, while DTSs had no epitenon at all, only part of endotenon was remained. Furthermore, the DBTSs, and DTSs with thickness of 900 μm had complete fascicles, while DTSs with thickness less than 600 μm had almost no complete fascicles. The fibrous configuration of epitenon was well-preserved in the surface of the DBTSs but the surface ultrastructure of the DTSs was aligned collagen fibers based on scanning electron microscopy examination. The results of transmission electron microscopy showed that there was no significant difference between the DBTSs and DTSs. Mechanically, the DBTSs and DTSs with thickness of 900 μm showed similar ultimate tensile strength and stiffness to native tendon segments (NTSs). The strain at break and suture retention strength of the DBTSs showed much higher than that of the DTSs (p < 0.05). Additionally, the DBTSs showed higher ultimate load than the DTSs when these scaffolds were sutured with NTSs (p < 0.05) through the modified Kessler technique based on a uniaxial tensile test. This study demonstrated that DTSs may be used as a patch for reinforcing tendon repair, while DBTSs may be used as a bridge for reconstructing tendon defects.

The study on natural aging of fiber reinforced composite, delamination damage behavior and damage pattern recognition plays a significant role in structural health monitoring of the material. In this study, acoustic emission is used to investigate damage evolution process and damage mechanisms in unidirectional glass and carbon-glass orthogonal woven fiber reinforced composites containing symmetric multiple delaminations under three point bending testing. Based on the principle of control variables, four kinds of specimens are manufactured to investigate the comparative study for the effects of delaminations, reinforced materials and fiber orientation on buckling failure behaviors and the effects of aging on mechanical properties. The results indicate that the degradation of strength and stiffness of composite can be influenced by the existence of delamination defects and natural aging condition. Both negative and positive effects can be generated by natural aging condition. Moreover, reinforced materials, porosity and fiber orientation are important factors influencing the reliability of composite. Clustering results of unidirectional fiber reinforced composites indicate interphase failure is the main damage component, moreover, the existence of symmetrical multiple delaminations will aggravate the damage of composite and make instability failure characterized by intermittency.

P-type implanted metal oxide semiconductor capacitors (MOSCAPs) and metal oxide semiconductor field effect transistors (MOSFETs) have been fabricated. The characteristics of hole trapping at the interface of SiO2/SiC are investigated through capacitance-voltage (CV) measurements with different starting voltages. The negative shift voltage ∆Vshift and the hysteresis voltages ∆VH which caused by the hole traps in the MOSCAPs and MOSFETs are extracted from CV results. The results show that the hole traps extracted from MOSCAPs are larger than the that extracted from the threshold voltage shift in the MOSFETs. It suggests holes trapping are the primary mechanism contributing to the NBTI, but not all the holes work. Part of the hole traps are compensation by sufficient electrons in the MOSFET structure.

In recent years, we investigated the structure and photoelectric properties of Silicon carbide nanowires (SiCNWs) with different morphologies and sizes by using the first-principle in density functional theory, and found a phenomenon that is opposite to quantum size effect, namely, the band gap of nanowires increases with the increase of the diameter. To reveal the nature of this phenomenon, we further carry out the passivation of SiCNWs. The results show that the hydrogenated SiCNWs are direct band gap semiconductors, and the band gap decreases with the diameter increasing, which indicates the dangling bonds of the SiCNWs suppress its quantum size effect. The optical properties of SiCNWs with different diameters before and after hydrogenated are compared, we found that these surface dangling bonds lead to spectral shift which is different with quantum size effect of SiCNWs. These results have potential scientific value to deepen the understanding of the photoelectric properties of SiCNWs and to promote the development of optoelectronic devices.

The electronic structure and optical properties of the nitrogen and phosphorus doped silicon carbide nanowires (SiCNWs) are investigated using first-principle calculations based on density functional theory . The results show doping can change the type of the band gap and improve the conductivity . However, the doped SiCNWs form a discrete impurity levels at the Fermi energy, and the dispersion degree decreases with the diameter increasing. In order to reveal the root of this phenomenon, we hydrogenated the doped SiCNWs, found that the surface dangling bonds were saturated, and the discrete impurity levels are degeneracy, which indicates that the discrete impurity band of the doped SiCNWs is derived from the dangling bonds. The surface passivation can degenerate the impurity levels. Therefore, both doping and surface passivation can better improve the photoelectric properties of the SiCNWs. The result can provide additional candidates in producing nano-optoelectronic devices.

An investigation on the microstructural evolution and self-healing mechanisms of ZrCu nanocrystalline/amorphous laminated alloy (NALA) has been conducted by molecular dynamics (MD) simulation in this study. By implementing a comparative structural-model evaluation with representative ZrCu nanocrystal laminated alloy (NLA), an anti-irradiation performance for NALA was established. Specifically, it was found that the phase boundaries (PBs) in NALA possessed the intrinsic capacities to completely or effectively annihilate defects. It was confirmed through the evolution of a “diffusion-capture” mechanism that PBs can completely and rapidly annihilate vacancies by self-migration. Furthermore, in contrast to NLA, it was unraveled that NALA can effectively recover destroyed nanocrystal regions induced by collision cascades due to a more spontaneously distinctive/competitive epitaxial crystal growth of the molten matter. The discoveries and findings of this study will potentially facilitate the development of state-of-the-art materials with high-irradiation tolerance.

The solvent extraction separation of lithium isotopes has become of growing interest due to the need for 6Li and 7Li isotopes in the nuclear industry. A one-step synthesis of room temperature ionic liquid with low viscosity 1-Ethyl-3-methylimidazolium bis(trifluoromethylsulfonyl)imide ([EMIm][NTf2]) (with reaction yields of 87.47%) was used by the ultrasonic method. The addition of ionic liquid [EMIm][NTf2] in the system significantly improved the extraction efficiency and separation factor compared to the traditional organic solvent anisole for extraction separation of lithium isotopes. The distribution ratio increased from 0.00145 (with the single stage separation factor of 1.024 ± 0.001) to 0.134 (with the single stage separation factor of 1.034 ± 0.001). Furthermore, a multi-stage extraction process was intended to enhance lithium isotope separation performance. Each stage of stripping can be considered as an extraction separation equilibrium process, in which the strip liquor from the load organic phase is used for separation in the next stage as the “original aqueous solution”. The abundance of 6Li+ gradually improved with an increase in the extraction stages. The relative abundance of 6Li+ increased by 1.492% at the 20-stage extraction separation (from 7.53% to 9.022%). This new and simple approach (stripping cross-flow multistage method (SCFM)) was to achieve large enrichment of lighter isotopes of lithium (6Li+) by combined extraction and stripping process. In summary, the present study offers the possibility for the enrichment of 6Li+ during lithium isotope extraction separation.

The phase and physicochemical properties diagrams of the quaternary system (Li2B4O7 + Na2B4O7 + Mg2B6O11) at 288.15 K and 0.1 MPa were constructed using the solubilities, densities, and refractive indices measured. In the phase diagrams of the system there are one invariant point, three univariant isothermic dissolution curves, and three crystallization regions corresponding to Li2B4O7 · 3H2O, Na2B4O7 · 10H2O, and Mg2B6O11 · 15H2O, respectively. The solution density, refractive index of the quaternary system changes regularly with the increasing of Li2B4O7 concentration. The calculated values of density and refractive index using empirical equations of the quaternary system are in good agreement with the experimental values.

In this study, a series of binary mixtures of stearic acid (SA) and acetanilide (AA) at various mass fractions were prepared. A novel binary mixture of SA and AA in the ratio of 81.0:19.0 mol% is shown to be an eutectic mixture with melting temperature of 342.45 ± 0.25 K, melting latent heat of 220.04 ± 10.02 J·g-1. In order to improve the thermal properties of SA-AA eutectic mixture so as to obtain a better composite phase change materials (CPCM) with high thermal conductivity, large heat storage capacity, good thermal stability and reliability for heat energy storage, expanded graphite (EG) at different mass fractions is added into SA-AA eutectic mixture. The results exhibited it remarkable energy storage capacity with a latent heat of CPCM of 176.14 J·g-1 compared to most of the organic eutectic mixture composite. The thermal conductivity of the CPCM was enhanced by 14.5 times comparing to SA-AA eutectic mixture. And the thermo-physical properties of the SA-AA/EG CPCM after 100 accelerated thermal cycles were slightly decreased which did not distinct influence on heat storage. Thus, the prepared SA-AA/EG CPCM is a promising material for latent heat storage systems.

Incorporation of the secondary oxide phase into the manganite composite capable of enhancing low-field magnetoresistance (LFMR) for viability in high-performance spintronic applications. Polycrystalline La0.67Ca0.33MnO3 (LCMO) was prepared via the sol–gel route in this study. The structural, microstructural, magnetic, electrical, and magneto-transport properties of (1−x) LCMO: x NiO, x = 0.00, 0.05, 0.10, 0.15 and 0.20 were investigated in detail. The X-ray diffraction (XRD) patterns showed the coexistence of LCMO and NiO in the composites. The microstructural analysis indicated the amount of NiO nanoparticles segregated at the grain boundaries or on the surface of LCMO grains increased with the increasing secondary phase content. LCMO and NiO still retained their individual magnetic phase as observed from AC susceptibility (ACS) measurement. This further confirmed that there is no interfacial diffusion reaction between these two compounds. The NiO nanoparticle acted as a barrier to charge transport and caused an increase in resistivity for composite samples. The residual resistivity due to the grain/domain boundary is responsible for the scattering mechanism in the metallic region as suggested by the theoretical model fitting, ρ(T)=ρ0+ρ2T2+ρ4.5T4.5. The magnetoresistance values of LCMO and its composites were found to increase monotonically with the decrease in temperature. Hence, the LFMR was observed. Nonetheless, the slight reduction of LFMR in composites was attributed to the thick boundary layer created by NiO and impaired the spin polarised tunnelling process.

In this paper, a novel method, multi-stage cross-flow separation of lithium isotopes by organic liquid film method was investigated. A green organic extraction phase was formed with ionic liquid-B15C5-anisole, and the bis(trifluoromethanesulfonyl)imide solution was used as a multi-stage cross-flow balance liquid. The abundance of 6Li in the 20-stage cross-flow extraction increased from 7.51% to 8.17%. The effect of the concentration of bis(trifluoromethanesulfonyl)imide on the stripping of lithium ions in the organic extraction phase and the loss of lithium ions during the multi-stage cross-flow process was studied. Also, the number of theoretical cross-flow stages of the abundance of 6Li (30%) that can be used as nuclear fuel was predicted.

Natural biomaterials have attracted great interest for the fabrication of biocompatible memristors. Here, dense and smooth milk films were deposited on the Pt/SiO2/Si substrate by spin-coating method and resistive switching (RS) devices based milk films with the configuration of Ag/milk/Pt/SiO2/Si are fabricated for the first time. Furthermore, memory RS (MRS) and threshold RS (TRS) effects coexist in the devices, which can be controlled by appropriately setting the compliance current (I cc). The current conduction mechanisms of the devices with MRS and TRS effects are controlled by typical trap-controlled space charge limited current (SCLC) conduction and filamentary conduction mechanism. The good RS performances of the milk-based devices make them promising for sustainable bioelectronics and novel logic device applications.

Compared with the tradition cooling technology, the evaporative cooling technology has the advantage of energy-saving, safety and reliability. So a self-circulating evaporative cooling structure was proposed. The narrow flow channels were designed between disk-type windings. The evaporative coolant flows in the narrow flow channels and takes away the heat loss through phase transition. In this paper the resistance characteristics of the system were studied through experiment based on the 900kVA transformer prototype.

An oxalic acid dihydrate/boric acid (OCD-BA) binary eutectic mixtures containing 88 wt% OCD and 12 wt% BA was investigated as a novel phase change material (PCM) with high latent heat and thermal stability. The solid-liquid phase diagram of binary systems is established, and the phase change temperature of OCD-BA binary eutectic mixture is 87.3 °C and the latent heats of the melting and crystallization process are 344 J g−1 and 262 J g−1, respectively. Its thermophysical properties and thermal stability were studied using differential scanning calorimetry (DSC), Fourier transform infrared (FT-IR) spectroscopy, X-ray diffraction (XRD), and Scanning electron microscopy-Energy dispersive spectroscopy (SEM-EDS). Its thermal stability was investigated in situ through 100 cycles using DSC and 1000 thermal cycling tests using Refrigerated and heating circulators (RHC). The latent heat of melting still exceed 280 J g−1 after 1000 heating/cooling cycles. The heat release platform sustained 5 h at more than 70.0 °C, and the degree of supercooling was only 1.0 °C according to T-history method. These results indicate that the newly prepared OCD-BA binary eutectic mixture is a potential PCM for thermal storage tanks.

Magnesium rechargeable batteries potentially offer high-energy density, safety, and low cost due to the ability to employ divalent, dendrite-free, and earth-abundant magnesium metal anode. Despite recent progress, further development remains stagnated mainly due to the sluggish scission of magnesium-chloride bond and slow diffusion of divalent magnesium cations in cathodes. Here we report a battery chemistry that utilizes magnesium monochloride cations in expanded titanium disulfide. Combined theoretical modeling, spectroscopic analysis, and electrochemical study reveal fast diffusion kinetics of magnesium monochloride cations without scission of magnesium-chloride bond. The battery demonstrates the reversible intercalation of 1 and 1.7 magnesium monochloride cations per titanium at 25 and 60 °C, respectively, corresponding to up to 400 mAh g−1 capacity based on the mass of titanium disulfide. The large capacity accompanies with excellent rate and cycling performances even at room temperature, opening up possibilities for a variety of effective intercalation hosts for multivalent-ion batteries., Magnesium rechargeable batteries potentially offer high-energy density, safety, and low cost. Here the authors show a battery that reversibly intercalates magnesium monochloride cations with excellent rate and cycle performances in addition to the large capacity.

Quinones with their structural diversity and electrochemical reversibility are among the most promising organic electrode materials. One distinct feature of quinones is their cross-conjugated structure, the importance of which in the design of organic electrode materials is so far overlooked. Here we report the design, synthesis, and characterizations of two cross-conjugated quinone oligomers (PBDTD and PBDTDS) and their nanocomposites with carbon nanotubes as potential low-cost organic electrode materials for Li-ion batteries. We investigate the effect of conjugation structure and molecular conformations (planar vs. helical) on electrochemical properties such as electronic conductivity, ionic conductivity, and electrode kinetics. Both quinones deliver similar specific capacity over 200 mA h g–1 at 2.5 V versus Li/Li+ with excellent stability over 250 cycles. In particular, the difference in their rate performance is mainly determined by two aspects. First, cross-conjugation of PBDTD becomes electron transport-favorable through-conjugation after reduction, while PBDTDS is always cross-conjugated. Second, the planar conformation of PBDTD facilitates electron-transfer compared with the helical PBDTDS. This work provides insights into the popular yet less understood cross-conjugated quinone-based electrode materials and will stimulate the design of better quinone materials to achieve high-performance organic batteries.

The mechanism of material removal through cool electrode electrical discharge machining (EDM) was investigated in this study by using single pulse discharge method. The influence of electrode temperature on the electric erosion pit morphology on the surface of the electrode and workpiece was analyzed. Finite element simulation was conducted on the temperature field between the electrode and workpiece under different electrode temperatures, and the simulation results were verified through a single pulse experiment. Under the same single pulse discharge parameters, when the electrode temperature was −20, 20, and 60 °C, the electric erosion pit diameter on the electrode surface increased to 290, 350, and 403 μm, respectively; the change in electric erosion pit diameter on the workpiece surface was small, and the corresponding values were 690, 705, and 718 μm. However, the bulge of the electric erosion pit on the surface of the workpiece became increasingly obvious, and the surface became unsmooth. The results of the single pulse experiment and the finite element simulation were identical. A comparative experiment involving the machining of Ti-6Al-4V titanium alloy was conducted with cool electrode and conventional EDM. Electrode wear, surface roughness, and machining efficiency were analyzed. Compared with that in conventional EDM, electrode wear decreased by 24.5%, the material removal rate increased by 14.16%, and surface roughness decreased by 14.14% in cool electrode EDM. Reducing the electrode temperature changed the electric erosion pit morphology on the electrode and workpiece surface, reduced electrode wear, improved surface processing quality, and increased processing efficiency.

The thermal properties of caprylic acid, nonanoic acid and their binary system were investigated by differential scanning calorimetry (DSC). The phase diagram for the binary system was constructed, and the experiment results showed that the eutectic temperature and the molar fraction of caprylic acid for the eutectic mixture are 1.83 °C and 0.483, respectively. To satisfy the application demands of the temperature scope from 5 °C to 15 °C, another binary mixture for the binary system with a molar fraction of 0.814 for caprylic acid component is found successfully, and it has good thermal properties that the melting temperature and the latent heat are 7.6 °C and 123 J g−1, respectively. What is more, the latent heat and melting temperature for the binary mixture do not change at all nearly after being cycled 100 times during the whole melting process. As a novel phase change material (PCM) for application in the field of air conditioning and cooling, the binary mixture has own unique thermal advantages.

Shape-stabilized composite phase change materials composed of sebacic acid (SA) and MCM-41 were prepared by a facile blending and impregnating method. Various characterization techniques were carried out to characterize their structural and thermal properties, including thermogravimetry (TG) analyses and differential scanning calorimetry (DSC), X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FT-IR), and scanning electron microscopy. The XRD and FT-IR results indicated the interactions between SA and MCM-41, such as the capillary force and the hydrogen bonding, resulting in the confined crystallization process. As a result, the SA that was confined was amorphous. The TG analysis results showed that the presence of MCM-41 practically resulted in an overlapping of the two decomposition stages. The DSC analysis demonstrated that a decrease in the SA content was accompanied by a continuous decrease in the melting point and phase change enthalpy of the composites.

Thermal properties and stabilities of the eutectic mixture: 1,6-hexanediol (HE) and lauric acid (LA) as a new phase change material (PCM) for latent heat thermal energy storage (TES) were investigated. Differential scanning calorimetry (DSC) results indicated that the aforementioned HE/LA mixture with eutectic composition (70/30 wt.%) was a suitable PCM in terms of melting point (Tpeak = 36.92 ± 0.71 °C) and latent heat of fusion (ΔHm = 177.11 ± 7.93 J g−1). After 1000 thermal cycles, the change in melting point for the eutectic mixture was in the range of −0.49% to −1.19%, and the change in latent heat of fusion was in the range of −0.22% to −3.24%. The eutectic mixture was thermally and chemically stable according to results of thermogravimetric analysis (TGA), volatile test and Fourier Transform Infrared (FT-IR) spectroscopic analysis. Therefore, the HE/LA eutectic mixture is an effective TES material to reduce energy consumption.

A lightly doped P-well field-limiting rings (FLRs) termination on 4H-SiC vertical double-implanted metal-oxide-semiconductor field-effect transistors (VDMOSFETs) has been investigated. Based on the simulation, the proposed termination applied to 4H-SiC VDMOSFET could achieve an almost same breakdown voltage (BV) and have the advantage of lower ion-implantation damage comparing with P + FLRs termination. Meanwhile, this kind of termination also reduces the difficulty and consumption of fabrication process. 4H-SiC VDMOSFETs with lightly doped P-well (FLRs) termination have been fabricated on 10 μm thick epi-layer with nitrogen doping concentration of 6.2 × 10 15 cm −3 . The maximum breakdown voltage of the 4H-SiC VDMOSFETs has achieved as high as 1610 V at a current of 15 μA, which is very close to the simulated result of 1643 V and about 90% of the plane parallel breakdown voltage of 1780 V. It is considered that P-well FLRs termination is an effective, robust and process-tolerant termination structure suitable for 4H-SiC VDMOSFET.

Low stability, reliability, and corrosion are considerable challenges to widespread application of succinic acid (SA) as phase change material (PCM). Here, we present a novel medium-temperature form-stable phase change material (FSPCM) aiming to eliminate these obstacles. In this study, FSPCM was fabricated by adsorbing eutectics of adipic acid (AA) and SA into expanded graphite (EG). The molar ratio of AA and SA in eutectics was determined to be 7:3, and the optimal mass ratio of EG in FSPCM is ca. 0.1. The composite was characterized by diffraction scanning calorimetry, scanning electron microscopy, Fourier transform infrared spectrometer, X-ray diffractometer, and thermal gravimetric analyzer. The results showed that the FSPCM melts at ca. 135 °C with latent heat storage of 206 J/g. No notable change of thermal behavior in FSPCM was observed after experienced 100 accelerated cycle test. Compared to SA, both the stability and reliability were promoted in FSPCM. Besides, the leakage of dicarboxylic acid was prevented, thus the corrosion was alleviated. It is envisioned that the as-prepared FSPCM have considerable potential in medium-temperature latent heat storage.

An adipic acid/boric acid (AA–BA) binary eutectic mixture containing 80 wt % adipic acid and 20 wt % boric acid was investigated as a new phase change material (PCM) with high latent heat, high thermal stability, and low cost. The material′s thermophysical properties and thermal stability were studied using differential scanning calorimetry (DSC), X-Ray Diffraction (XRD), and thermogravimetric analysis (TGA). The thermal stability was investigated in situ over 100 cycles using DSC. The phase change temperature of the AA–BA binary eutectic mixture was 135.04 °C and the latent heats of the melting and crystallization process were 283.42 and 272.16 J g−1, respectively. The latent heat of melting only dropped 4.94 % after in situ 100 cycles using DSC. Following comparison of thermal properties and price of the AA–BA eutectic mixture PCM with those of some composite PCMs, the results indicate that the newly prepared AA–BA eutectic mixture is a potential phase change material for thermal storage tanks.

We investigated the thermal properties and thermal reliability of stearic acid- n -butyramide and stearic acid- n -octanamide binary eutectic mixtures, as phase change materials for low temperature solar heat energy storage. The solid-liquid phase diagrams of two binary systems were established, and the eutectic compositions of binary mixtures and corresponding thermal properties were verified: (1) stearic acid- n -butyramide, the eutectic composition is 0.551 ± 0.005 mol fraction stearic acid and (2) stearic acid- n -octanamide, the eutectic composition is 0.589 ± 0.005 mol fraction stearic acid. The eutectic compositions have high latent heat of fusion Δ H m = 198.38 ± 10.22 J·g −1 , Δ H m = 198.98 ± 8.56 J·g −1 and melting temperature T peak = 337.41 ± 1.93 K, T peak = 336.28 ± 2.00 K for stearic acid- n -butyramide and stearic acid- n -octanamide binary mixture, respectively. A modeling approach on the bases of thermodynamics is employed to predict solid-liquid equilibria of the studied mixtures and their latent heats of fusion. The simulated results are in good agreement with experimental results. The heat capacity of the solid phase measured are 1.69 ± 0.2 J·g −1 ·K −1 , 1.61 ± 0.2 J·g −1 ·K −1 and the thermal conductivity of the solid phase are 0.222 ± 0.03 W·m −1 ·K −1 , 0.276 ± 0.034 W·m −1 ·K −1 at 298.15 K for stearic acid- n -butyramide and stearic acid- n -octanamide binary mixture, respectively. The mixture has a good thermal stability after 100 melt-freeze cycles. As novel phase change materials for solar heat applications, the studied eutectic mixtures have attractive thermal performance and great utility.

Oxalic acid dihydrate (OAD) which has the high initial phase transition enthalpy is a promising PCM for thermal energy storage (TES). However, large degradations of thermophysical properties over time have restricted further application of OAD. Cyclic stability of OAD, which means thermal cycling stability, needs to be improved to give full play to its potential for TES. In this paper, cyclic stability of OAD was determined by using ordinary aluminum pans and high pressure gold-plated pans in DSC measurement. In addition, PEG (with different molecular weights) was added to improve cyclic stability of OAD. Results show that the containers with good sealing performance and strong corrosion resistance are vital for the application of OAD. Meanwhile, adding 2.5% PEG 6000 gives better cyclic stability to OAD without affecting its melting temperature neither decreasing significantly its heat of fusion.