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Challenges related to poor electronic conductivity and cycling stability have impeded the development and utilization of Na3V2(PO4)3(NVP). Therefore, this study focuses on enhancing the performance of NVPby employing a sol–gel method to design various gradients of F/Al-doped and carbon nanotube (CNT)-enwrapped NVPmaterials. The introduction of F doping replacing PO4tetrahedra reduces the occupied space, while F monomers can establish stronger bonds with VO6octahedral pillars closer to O atoms. Additionally, Al doping introduces a new AlO6octahedral structure at the V site, strengthening the 3D framework. The synergistic substitution of F and Al contributes to improving the stability of the framework, which enhances the Na+migration channels and overall electrochemical performance. Furthermore, the coating of CNTs plays a crucial role in creating a favorable interface transition layer that facilitates efficient electron transport and enhances electronic conductivity. Comprehensively, the modified FAl-2 exhibits a high capacity of 115.8 mA h g–1at 0.1C. It reveals 89.3 mA h g–1at 60C and maintains 83.8 mA h g–1after 2000 cycles, indicating a capacity retention rate of 93.84%. Electrochemical ex situ X-ray diffraction (XRD) demonstrates that FAl-2 behaves at relatively low values (0.328%–1.075%) of volume shrinkage during the whole charge/discharge process, indicating its near-zero strain property. The postcycled XRD and X-ray photoelectron spectroscopy further verify the significantly enhanced crystal structural stability of FAl-2. Moreover, FAl-2 possesses a higher thermal runaway temperature, indicating a superior thermal stability. The self-releasing heat trend observed in FAl-2 can offer valuable insights into the design of battery management systems.

• Novel microencapsulated composites with superior comprehensive performance were prepared. • The composites had the highest thermal conductivity of 0.50 W/(m K) and latent heat of 139.64 J/g. • The composite with carbon nanotubes showed good thermal stability and temperature control ability. • The synthesized composites could be applied in a battery thermal management system. • Reasonable analysis and interpretation of crystallization phenomena were provided. In order to maintain the optimal operating temperature of the battery surface and meet the demand for thermal storage technology, battery thermal management system based on phase change materials has attracted increasing interest. In this work, a kind of core-shell structured microcapsule was synthesized by an in-situ polymerization, where paraffin was used as the core, while methanol was applied to modify the melamine-formaldehyde shell to reduce toxicity and improve thermal stability. Moreover, three different types of heat conductive fillers with the same content of 10 wt.%, i.e., nano-Al 2 O 3 , nano-ZnO and carbon nanotubes were added, generating composites. The microcapsules were uniform, and were not affected by the thermal fillers, which were evenly dispersed around. The composite sample with carbon nanotubes (10 wt.%) showed the highest thermal conductivity of 0.50 W/(m K) and latent heat of 139.64 J/g. Furthermore, according to the leakage testing and battery charge/discharge experiments, compared with Al 2 O 3 and ZnO, the addition of carbon nanotubes remarkably enhances the heat storage ability as latent heat from 126.98 J/g for the prepared sample with Al 2 O 3 and 125.86 J/g for the one with ZnO, then to 139.64 J/g, as well as dissipation performance as a cooling effect by decreasing the surface temperature of battery from 2% to 12% of microcapsule, composite sample with carbon nanotubes presents a broad application prospect in battery thermal management system and energy storage field. [ABSTRACT FROM AUTHOR]

Developing efficient bimetallic Pt-based catalyst is highly desired for propane dehydrogenation (PDH) process. Typical co-impregnation method often results in inhomogeneous distributions of metal species on supports. Herein, we reported a facile method to support PtZn bimetal alloy nanoparticles onto Beta zeolite, mainly existing as highly dispersed Pt1Zn1alloy species. Zn@Beta was first synthesized by hydrothermal method with the aid of ethylenediamine (EDA), leading to the introduction of Zn atoms into zeolite lattice. An impregnation process was subsequently employed to support Pt species. During this process, skeleton Zn atoms migrated out of the framework and were then reduced together with Pt in flowing H2, leading to the formation of PtZn alloy with mainly Pt1Zn1structures. Cs-corrected high-angle annular dark-field scanning transmission election microscope and X-ray absorption fine structure analyses revealed that this method was more conducive to the formation of PtZn alloy compared with the co-impregnation method. The obtained catalyst of 0.3Pt1Zn@Beta exhibited initial propane conversion of 36.8% and propylene selectivity of 99.3% combined with low deactivation rate (0.004 h–1) over 24 h with propane WHSV of 4.7 h–1at 550 °C. The catalyst also exhibited good PDH performance in a long-term reaction (180 h) and robustness during regeneration reactions by simply flushing hydrogen.

To obtain accurate output torque of robot joint for torque control, a built-in torque sensor is designed in this article. To enhance the performance of harmonic gear (HG), it is urgent to deal with the key issues in terms of the errors of sensing and positioning, and torque ripple interference. To handle these aforementioned key issues, four pairs of symmetrically distributed strain gauges are pasted on the bottom of the flexspline. Then, a precise positioning method based on laser marking is proposed to improve the positioning accuracy of the strain gauges. Moreover, Kalman filter (KF) is utilized to reduce torque ripple interference in the output signal of the strain gauges. Additionally, the designed device is evaluated by experimental tests which are conducted on prototype trial production. Synchronously, the relationship between the flexspline torque and the joint output torque is verified and the polynomial is used to represent the relationship of the measured torque for the built-in torque sensor and the standard torque sensor in the static and dynamic conditions. Finally, a friction model is presented and identified. Comprehensive comparative experiments is performed the performance of the build-in torque sensor in terms of estimation accuracy and control and it shows that the designed built-in torque sensor with friction compensation (FC) can be improved ten times in comparison with that of without FC in terms of steady-state mean error and mean value of measurement error. What is more, this designed build-in torque sensor holds tremendous potential for making the compact and lightweight motion joint module, especially for cooperative robot and robotic supernumerary limb.

The thermal stability of lithiated graphite plays an important role in the thermal safety of lithium-ion batteries (LIBs). However, a safer graphite anode usually leads to a lower energy density. This article starts from multiple hazardous factors of lithiated graphite when thermal runaway occurs, considering the impact of defects on the electrochemical performance and thermal safety of graphite electrodes. In this study, turbostratic graphite was prepared as the anode for LIBs. The stacking of graphite was altered to form narrow pores and spherical aggregates, and introducing defects. By varying the ball-milling time, the structural changes of different ball-milled graphites were analyzed. The impact mechanism of defect structure on electrode electrochemical performance and safety performance was investigated. The results show that the spherical structure and large specific surface area are beneficial to increase the active sites and delay the self-heating of the battery. The formation of defects and pores increases the adsorption sites, which makes the surface adsorption of Li+dominant and improves the ion diffusion. In addition, the dominance of surface adsorption and desorption effectively suppresses the problem of graphite flake peeling and intensified thermal runaway caused by graphite phase transition and lithium evolution heat release at high temperature. The thermal safety test was carried out by accelerated calorimeter (ARC), and its thermodynamics and reaction kinetics were quantitatively analyzed. It was proved that the introduction of surface adsorption lithium storage method successfully delayed the thermal runaway of the battery, realizing the balance between high electrochemical performance and high safety.

A fire whirl is a kind of spinning flow accompanied by chemical changes. It has a combustion-enhancing effect, increasing the fire’s heat release rate and may induce catastrophic consequences. However, the combustion characteristics of a fire whirl at dynamic pressure are still unknown. This experiment was conducted in a sizeable low-pressure chamber with dimensions of 3.0 m × 2.0 m × 2.0 m, in which a small-sized fire whirl was generated using a square vertical slot with variable slit width. The ambient pressure was reduced to the target pressure by the low-pressure chamber, and a dynamically pressurized environment was created by controlling the air inlet rate. This experiment investigates characteristic parameters such as combustion rate, heat radiation flux, and flame height of the fire whirl. The experimental results show that the flame height of the fire whirl with pressure changes as a result of the first increase and then maintains the same; the fire whirl has a pronounced combustion enhancement effect, and the combustion rate is about 3.5 times that of the ordinary pool fire; four walls open slit fire whirl combustion there is a “critical width,” the closer the width, the higher the mass combustion rate, the more stable the flow field, the more the ratio between the burning rate and the characteristic length of the oil basin, the more the ratio between the dimensionless number and the Grashof number is close to a linear relationship. The heat radiation flux increases with increasing pressure, and there is a linear relationship between Qr″/P21/4and P-2/3, where Qr″is the flame radiation and Pis the pressure.

Graphical abstract: The burning behaviors of 21700 cylinders after different immersion duration were investigated, which might help evaluate the fire risk of batteries and improve safety

Currently, the poor intrinsic electronic and ionic conductivity significantly limits the further development of Na3V2(PO4)3(NVP). In this paper, a feasible improvement strategy is proposed, which uses the sol-gel method to doped Lu3+into Na3V2(PO4)3. According to the rietveld XRD occupancy refinement, the introduced Lu element occupies the Na1 site, which hardly affects the reversible de-intercalation of the two Na+at Na2 site, behaving no side effects on the reversible capacity properties of the modified material. Besides, due to the smaller ionic radius of Lu3+than that of Na+(86.1 Å vs. 102 Å), Lu3+substitution can increase the intercellular space within the crystal bulk to accelerate ionic migration and improve the ionic conductivity. Meanwhile, hypervalent and multicharged Lu3+at Na1 site can cause the slight lattice distortions to induce more active sites for the storage of Na+, favorably increasing the reversible capacity. Furthermore, post-cycling XRD/SEM/XPS measurements demonstrate the significantly improved structural stability of NVP/C@Lu-1 % sample. Before and after cycling XPS spectra verify the stable existence of newly generated LuO band at 199.12 eV, which plays the role of an anchoring column to connect the crystal construction between lattice planes, and reduces the lattice strain to enhance the structure. According to the comparison of V2p XPS spectra before and after cycling, the peak location tends to move lower binding energy after introducing Lu3+at Na1 site, indicating that NVP/C@Lu-1 % possesses a more stabilized framework. Overall, the optimized NVP/C@Lu-1 % submits an astonishing value of 123.9 mAh g−1at 0.1C. Even at 7, 30, and 80C, it can release capacities of 97.1, 79.6 and 75.5 mAh g−1, and after 2000, 7500, and 8000 cycles, the capacities still keep 90.5, 73.2 and 68.3 mAh g−1with retention of 93 %, 92 %, and 90.5 %.

Graphical abstract: The catalytic incineration and pyrolysis of polyethylene were investigated, which might provide reference for the waste plastic recycling processing design.

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Expressway tunnels are semi-enclosed structures characterized by monotonous alignment transitions and unique lighting environments, which can easily lead to drivers developing constrained and irritable psychology. This may result in risky behaviors such as speeding and fatigued driving. Previous research on tunnel driving behavior mainly focuses on visual factors, neglecting the nonstationary time-series impacts of combined parameters on risky driving. Firstly, 30 drivers were recruited to carry out the real test. Then, based on the evolution of time series, drawing inspiration from the concept of lineage in biology, and considering multiple driving performance indicators, driving behavior chains and the feature spectrum were constructed. The characteristics of the behavioral spectrum were divided into six groups: electroencephalogram, heart rate, eye movement, speed, steering, and car-following behavior. Subsequently, spectral analysis using the spectral radius property of matrix theory revealed distinctive characteristics of risky driving behavior. The study deeply explored the inducing mechanism, hidden patterns, and rules of risky driving behavior under the coupling effect of tunnel environment and drivers’ attributes. Finally, the significant features that influence driving behavior were used as input variables for constructing identification models using the Adaptive Boosting (AdaBoost) and Random Forest (RF) algorithms. Synthetic Minority Over-sampling Technique (SMOTE) and Adaptive Synthetic Sampling (ADASYN) were employed for oversampling. The results indicate that the ADASYN-RF algorithm outperformed others, achieving a precise recall rate area under the curve (AUPRC) of 0.978 when using the spectral radius of the speed and steering groups as input variables. These findings offer theoretical guidance for developing tunnel traffic safety strategies.

Na3V2(PO4)3(NVP) faces several challenges, such as lower intrinsic electronic and ionic conductivities, which hinder its commercial viability. In this work, NVP system is modified by introducing sodium carboxymethyl cellulose (CMC) to achieve triple modification effects: sodium-rich, cross-linked carbon coating network, and carbon layer surface modification. Meanwhile, CMC, as a porous carbon substrate with large pores, provides a fast migration channel for Na+. Similarly, carbon nanotubes (CNTs) grown from the active particles become the connecting carriers between the active particles, thus effectively improving the electron transport. Notably, the SEM and TEM images after cycling verify the stabilized porous structure of the Na3V2(PO4)3/C@0.7wt.%CMC@CNTs (0.7wt.%CMC@CNTs) composite. Distinctively, the modified 0.7wt.%CMC@CNTs reveals a capacity of 111.4 mAh g-1at 0.1 C. It submits a high value of 105.0 mAh g-1at 1 C with a capacity retention rate of 84.10% after 1000 cycles. Even at 15 C, it still releases 86.6 mAh g-1with a low capacity decay rate of 0.0230% per cycle after 3600 cycles. Notably, its capacity retention reaches an astonishing 96.09% after 13000 cycles at an ultra-high rate of 80 C.

As the preferred medium for tunnel energy storage system (TESS), lithium-ion batteries (LIBs) are widely used in tunnel lighting, ventilation, fire protection, monitoring, and communications. Once the LIBs are thermally out of control, causing fire and explosion, its flammable and toxic fumes will spread in large quantities in the tunnel, seriously affecting the safety of the tunnel. Therefore, this review firstly introduces tunnel engineering, battery energy storage technology, LIBs thermal runaway (TR), and tunnel fire smoke and control. Secondly, the working principle and composition of LIBs in TESS are summarized. Thirdly, the reasons for TR of LIBs are summarized. Fourthly, the characteristics of the tunnel fire smoke that the research mainly focuses on, including the characteristics of flue gas diffusion and stratification, flue gas temperature distribution under the ceiling, flue gas countercurrent length, critical wind speed, and fire smoke composition of energy storage system. Finally, the suppression technologies and tunnel smoke control methods for LIBs fires are summarized. This review retrospects and summarizes the research on fires in TESS, and also points out some existing problems, which may open up new fields for future research on tunnel fires.

The nitrogen-doped carbon nanotubes (CNTs) were obtained by using methyl orange as a soft template and high temperature treatment, on which the layered double hydroxide (LDH) was grown in situ by hydrothermal method, and finally mixed with the phase change materials (PCM) by vacuum filtration to obtain a series of novel composite films with great flame retardancy and thermal conductivity. The use of cellulose nanofiber (CNF), polyvinylpyrrolidone (PVP) and polyethylene glycol (PEG) as PCM increased the film-forming properties, and the CNTs could improve the thermal conductivity of composites, while reducing the agglomeration of LDH nanolayers and improving the flame retardancy of the composite films. The results showed that the LDH grown on the nanotubes had a typical hexagonal lamellar structure, and its uniform distribution was the fundamental reason for the flame retardancy of the films which was verified by defined combustion experiments, the shortest self-extinguishing time and the least unburned area were achieved at a mass ratio of 7.14 % of LDH material. The melt and crystallization enthalpies of the thermally conductive flame-retardant films were 74.65 J/g−1and 74.82 J/g−1, and the thermal conductivity of the material was increased to 0.04129 W/(m·K) after the use of 2.5 % thermally conductive filler. It can reduce the temperature of LED by up to 5.9 °C during the LED opening process and up to 5.2 °C during the LED closing process.

Sodium-ion batteries (SIBs) are regarded as the most promising battery to replace lithium-ion batteries (LIBs) in the future. Na3V2(PO4)3(NVP), as an ideal positive electrode material for SIBs, is limited by poor electronic conductivity and low reversible capacity. In this paper, the double carbon resources of chitosan quaternary ammonium hydrogel (CHACC) and Polypyrrole (PPy) were introduced into NVP. Through the construction of double charge carriers, the high conductivity and the high reversible capacity of NVP which broke the theoretical limit were achieved. The introduction of CHACC brings the second charge carrier, ClO4−, in addition to Na+in NVP system. Furthermore, the conductive network and defect-rich carbon coatings formed by CHACC and PPy significantly improve the electronic conductivity and kinetics of the electrode. Comprehensively, the detailed functional mechanism of dual carriers in NVP is deeply investigated by ex-situ FTIR and XPS, revealing that ClO4−utilizes the N+in the carbonized substrate of CHACC and PPy as the binding sites to reversibly inserted/extracted from the carbon layer to provide additional capacities. Notably, the optimized CHACC-PPy-NVP submits superior sodium storage performance. It delivers a capacity of 148.3 and 139.3 mAh g−1at 0.1 and 1C, significantly exceeding the theoretical capacity (117.6 mAh g−1). Even at 140C, it still maintains a capacity value of 88.9 mAh g−1with 75.7 mAh g−1remaining after 2000 cycles, corresponding to a low decay rate of 0.007 % per cycle.

Objectives The aim of this study was to describe and evaluate a novel method of sliding bone graft combined with double locking plate fixation in treating femoral shaft nonunion.Methods Clinical data from patients with femoral shaft nonunion that was treated with sliding bone grafts combined with double locking plate fixation were retrospectively collected. Data included duration of surgery, blood loss, union rate, time to union and possible complications.Results Twenty-five patients included in the study were followed for a mean duration of 16.6 ± 2.6 months (range, 12–22 months). All of the fractures (100%) achieved bony union. Mean time to union was 6.0 ± 1.0 months (range, 4–8 months). No infections or medullary cavity occlusions were observed.Conclusions Sliding bone graft combined with double locking plate fixation was shown to be a safe, effective, and convenient surgical option for the treatment of nonunion, due to its high union rates with no complications. Further studies with larger sample sizes and longer-term follow-up are warranted.

Normal cells become cancer cells after a malignant transformation, but whether cancer cells can be reversed to normal status remains elusive. Here, we report that the combination of hepatocyte nuclear factor 1A (HNF1A), HNF4A and forkhead box protein A3 (FOXA3) synergistically reprograms hepatocellular carcinoma (HCC) cells to hepatocyte-like cells (reprogrammed hepatocytes, rHeps). Our results show that rHeps lose the malignant phenotypes of cancer cells and retrieve hepatocyte-specific characteristics including hepatocyte-like morphology; global expression pattern of genes and specific biomarkers of hepatocytes; and the unique hepatic functions of albumin (ALB) secretion, glycogen synthesis, low-density lipoprotein (LDL) uptake, urea production, cytochrome P450 enzymes induction and drug metabolism. Intratumoral injection of these three factors efficiently shrank patient-derived tumor xenografts and reprogrammed HCC cells in vivo. Most importantly, transplantation of rHeps in the liver of fumarylacetoacetate hydrolase-deficient (Fah−/−) mice led to the reconstruction of hepatic lobules and the restoration of hepatic function. Mechanistically, exogenous expression of HNF1A, HNF4A and FOXA3 in HCC cells initiated the endogenous expression of numerous hepatocyte nuclear factors, which promoted the conversion of HCC cells to hepatocyte-like cells. Collectively, our results indicate the successful conversion of hepatoma cells to hepatocyte-like cells, not only extending our current knowledge of cell reprogramming but also providing a route towards a novel therapeutic strategy for cancer.

Na3V2(PO4)3(NVP), possessing stabilized framework and high voltage platform, has attracted extensive attentions in the field of energy storage. However, the low conductivity restricts its further development. Herein, a novel strategy of defect regulation by Co2+substitution is proposed. Co2+doping not only generates beneficial hole carries resulting from the p-type doping to accelerate the electronic conductivity, but also favors to expand the interplanar spacing in the internal bulk of NVP system to enhance the ionic transportation. Moreover, theoretical calculation indicates the beneficial Co2+substitution modifies the electronic structure of NVP to reduce the band gap, as well as decline the energy barrier. Distinctively, the Co0.07-NVP/C composite delivers a high value of 114.4 mA h g−1at 0.1 C, almost close to its theoretical value (117.6 mA h g−1). It submits a reversible capacity of 104.6 mA h g−1 at 1 C and keeps 100.1 mA h g−1after 200 cycles with a retention value of 95.70%. Even at 10 C, it also can reveal a capacity of 101.6 mA h g−1and remains 81.8 mA h g−1after 1000 cycles.

In this work, the substrate of cellulose nanofiber (CNF) with polypyrrole (PPy) nanotube (PNT) composite (named as SF/PNT) membranes were prepared using vacuum filtration, which provided effective network for conducting electron and heat, simultaneously endowing the membranes with excellent thermal conductive performance and electromagnetic interference shielding effectiveness (EMI SE, 34.2 dB). Meanwhile, the SF/PNT composite membranes showed the electrical conductivity around 613 S/m, which also presented certain mechanical properties, with the latent heat of 155.2 J/g. In particular, the presence of Mg(OH)2and PNT network contributed remarkable anti-dripping performance and flame-retardant properties to the membranes during combustion. The provided novel SF/PNT composites indicated promise for a wide variety of applications in thermal energy storage, battery thermal management system, microelectronic packaging and smart buildings.

The complex chemical reactions and the safety properties of lithium-ion batteries (LIBs) with different cathode materials are various from each other. In this article, a cone calorimeter was used to measure the mass change, heat generation and gas release characteristics of three types of 18650 cylindrical LIBs with lithium iron phosphate (LFP), lithium cobalt oxide (LCO) or lithium nickel manganese cobalt oxide (NMC) as the positive electrode material. All samples were tested under 9 kinds of conditions combined state of charge (SOC) of 33 %, 66 %, 100 % with heat flux of 30 kW/m2, 45 kW/m2, 60 kW/m2, respectively. Especially, the principal component analysis (PCA) method was applied to further analyze the difference of thermal runaway (TR) behavior for the three kinds of batteries. Moreover, the influence of SOC and heat flux on the safety features of 18650-cylinder LIBs was analyzed. After comparing parameters such as mass loss rate (MLR), gas generation/consumption, heat release, toxicity among the tested 18650 cylindrical LIBs, the results displayed that the influence of external heat flux on the intensity of battery TR reactions was lower than that of SOC. The TR risk of LCO and NMC batteries with relatively high SOC was higher than that of LFP ones in large fire scenarios. When the fire scale was relatively small, the main factor that determined the risk of battery fire was the type of cathode, while which became SOC under the opposite situation of large-scale fire. PCA results showed that LFP and NMC batteries presented almost completely different TR characteristics, which could provide important references for battery design, corresponding fire investigation and attack.

The purpose of this study is to explore a new clean and environment protecting composite microcapsule material with 1-dodecanol (DD) as the core and modified methylated melamine-formaldehyde (MMF) as the shell, to meet the needs of low temperature heat or energy storage (0–40 °C). The microencapsulated phase change material (MPCM) base with a mass ratio of 14:3 was synthesized by in-situ emulsion polymerization, then two kinds of additives 10 wt% boron nitride (BN) and 5 wt% BN mixed with 5 wt% carbon nanotubes (CNTs) were applied to solve the defects of easy leakage and low thermal conductivity, while the samples were defined and shorted as BPCM and BCPCM, respectively. The experimental results showed that the prepared BCPCM presented good storage stability in the temperature range of 0–40 °C, which was due to its good thermal conductivity of 0.584 W/m·K, latent heat of 163.8 J/g, and strong supramolecular interaction between 1-DD and MMF. Through charging and discharging tests for batteries under low temperature, BCPCM indicated excellent thermal management performance, which proposed its application potential in the cryogenic storage environments and battery thermal management system (BTMS) field.

The generation of large numbers of functional human hepatocytes for cell-based approaches to liver disease is an important and unmet goal. Direct reprogramming of fibroblasts to hepatic lineages could offer a solution to this problem but so far has only been achieved with mouse cells. Here, we generated human induced hepatocytes (hiHeps) from fibroblasts by lentiviral expression of FOXA3, HNF1A, and HNF4A. hiHeps express hepatic gene programs, can be expanded in vitro, and display functions characteristic of mature hepatocytes, including cytochrome P450 enzyme activity and biliary drug clearance. Upon transplantation into mice with concanavalin-A-induced acute liver failure and fatal metabolic liver disease due to fumarylacetoacetate dehydrolase (Fah) deficiency, hiHeps restore the liver function and prolong survival. Collectively, our results demonstrate successful lineage conversion of nonhepatic human cells into mature hepatocytes with potential for biomedical and pharmaceutical applications.

Functional human hepatocytes xenografted into the liver of mice can be used as a model system to study pharmacokinetics, infection of hepatitis viruses, and the efficacy of hepatitis vaccines. Significant levels of liver xeno-repopulation have been reported in Fah−/−Rag2−/−Il2rg−/−mice. However, the high mortality and low breeding rate of this model may hinder its application. A new model, termed Fah−/−Nod/Scidmice, which combines the advantages of liver repopulation in Fah−/−mice with the ease of xenotransplantation in Nod/Scidmice was obtained by gradual cross-breeding. Fah−/−Nod/Scidmice were easily maintained in breeding colonies and in adult animal care facilities. FK506 treatment combined with gradual withdrawal of NTBC before cell transplantation ensured that Fah−/−Nod/Scidmice were susceptible to liver xeno-repopulation by human hepatocytes; the proportion of engrafted human hepatocytes reached 33.6%. The function of the expanded human hepatocytes within the chimeric liver was confirmed by weight curve analysis, the expression of characteristic proteins, and the biochemical analysis of liver function. These results show that Fah−/−Nod/Scidmice are an ideal humanized liver mouse model with many useful applications.

Functional human hepatocytes xeno-engrafted in mouse liver can be used as a model system to study hepatitis virus infection and vaccine efficacy. Significant liver xeno-repopulation has been reported in two kinds of genetically modified mice that have both immune deficiency and liver injury–induced donor hepatocyte selection: the uPA/SCIDmice and Fah−/−Rag2−/−Il2rg−/−mice. The lack of hardy breeding and the overly elaborated technique in these two models may hinder the potential future application of these models to hepatitis virus infection and vaccination studies. Improving the transplantation protocol for liver xeno-repopulation from human hepatocytes will increase the model efficiency and application. In this study, we successfully apply immunosuppressive drug treatments of anti-asialo GM1 and FK506 in Fah−/−Rag2−/−mice, resulting in significant liver xeno-repopulation from human hepatocytes and human fetal liver cells. This methodology decreases the risk of animal mortality during breeding and surgery. When infected with hepatitis B virus (HBV) sera, Fah−/−Rag2−/−mice with liver xeno-repopulation from human hepatocytes accumulate significant levels of HBV DNA and HBV proteins. Our new protocol for humanized liver could be applied in the study of human hepatitis virus infection in vivo, as well as the pharmacokinetics and efficacy of potential vaccines.

Na3V2(PO4)3(NVP) materials have emerged as a promising cathode for sodium ion batteries (SIBs). Herein, NVP is successfully optimized by dual-doping K/Co and enwrapping carbon nanotubes (CNTs) through a sol–gel method. Naturally, the occupation of K and Co in the Na1 sites and V sites can efficiently stabilize the crystal cell and provide the expanded Na+transport channels. The existence of tubular CNTs could restrict the crystal grain growth and effectively downsize the particle size and provide a shorter pathway for the migration of electrons and ions. Moreover, the amorphous carbon layers combined with the conductive CNTs form a favorable network for the accelerated electronic transportation. Furthermore, the ex situ XPS characterization reveals that an extra redox reaction pair of Co2+/Co3+is successfully activated at the high voltage range, resulting in superior capacity and energy density property for KC0.05/CNTs composites. Comprehensively, the optimized KC0.05/CNTs electrode exhibits a distinctive electrochemical property. It delivers an initial reversible capacity of 119.4 mA h g–1at 0.1 C, surpassing the theoretic value for the NVP system (117.6 mA h g–1). Moreover, the KC0.05/CNT electrode exhibits the initial capacity of 113.2 mA h g–1at 5 C and 105.8 mA h g–1at 10 C, and the maintained capacities at 500 cycles are 105.8 and 100.8 mA h g–1with outstanding retention values of 96.6 and 95.3%. Notably, it releases capacities of 99.8 and 84.5 mA h g–1at 50 and 100 C, and the capacity retention values at 2500 cycles are 66.2 and 58.8 mA h g–1, respectively. What is more, the KC0.05/CNTs//Bi2Se3asymmetric full cell exhibits a high capacity of 191.4 mA h g–1at 2.65 V, with the energy density being as high as 507 W h kg–1, demonstrating the eminent practical application potential of KC0.05/CNTs in SIBs.

In this work, the effect of the heat-treatment temperature of synthetic (artificial) graphite on the electrochemical performance of LiNi0.5Mn0.3Co0.2O2/graphite pouch cells was explored and compared with cells utilizing commercial-grade artificial and natural graphite materials. Two optimized electrolyte additive blends, 2% VC + 1% DTD and 1% LiPO2F2, were used in the cells tested. Physical properties of the different graphite electrodes, such as morphology, pore-size, crystallinity and thermal stability were investigated. Then, cells with each graphite material were tested with a variety of electrochemical techniques: ultra-high precision coulometry, long-term cycling, high-rate cycling, isothermal microcalorimetry, operando pressure tests and open circuit storage tests. Marginal benefits were found in electrochemical tests for cells with graphite materials that had been heat-treated to lower temperatures. However, in all tests, cells with synthetic graphite had superior performance compared to natural graphite.