As one of the most abundant and highly conserved molecular chaperones, the 70‐kDa heat shock proteins (Hsp70s) play a key role in maintaining cellular protein homeostasis (proteostasis), one of the ...most fundamental tasks for every living organism. In this role, Hsp70s are inextricably linked to many human diseases, most notably cancers and neurodegenerative diseases, and are increasingly recognized as important drug targets for developing novel therapeutics for these diseases. Hsp40s are a class of essential and universal partners for Hsp70s in almost all aspects of proteostasis. Thus, Hsp70s and Hsp40s together constitute one of the most important chaperone systems across all kingdoms of life. In recent years, we have witnessed significant progress in understanding the molecular mechanism of this chaperone system through structural and functional analysis. This review will focus on this recent progress, mainly from a structural perspective.
•Compound of ZnMn2O4 spheres anchored on jute porous carbon has been synthesized.•The composite material possessed a capacity of 1501.6 mA h g-1 after 200 cycles at 0.2 C.•At 2 C, it still has a ...capacity of 701.9 mA h g-1, and no capacity loss of 1000 cycles.
Compound of ZnMn2O4 spheres anchored on jute porous carbon has been synthesized via a template method and a facile hydrothermal method. The composite material has possessed a capacity of 1501.6 mA h g−1 after 200 cycles at a current density of 0.2 C. At a current density of 2 C, it still has a capacity of 701.9 mA h g−1, and no capacity loss of 1000 cycles. Display omitted
As anodes of lithium-ion batteries, transition metal oxide materials have been considerably studied due to their high theoretical specific capacities. However, their poor conductivities and the disintegration of their structures due to volume changes when charging and discharging have restricted the development of transition metal oxide anode materials in lithium-ion batteries. In this work, a novel ZnMn2O4 sphere/jute porous carbon composite material is prepared and displays a high capacity of 1501.6 mA h g−1 after 200 cycles at a current density of 0.2 C (1 C = 784 mA g−1). At a current density of 2 C, it still has a capacity of 701.9 mA h g−1 and no capacity loss for 1000 cycles. The reason for this excellent cycling stability is that the anode material has formed a special structure of ZnMn2O4 spheres composited with jute biomass porous carbon during the preparation process. Biomass porous carbon can promote charge transfer and reduce the volume change of ZnMn2O4. This work proposes an approach to prepare an environmentally friendly, high-performance lithium-ion battery anode material.
The activated carbon materials from the corn stalk core raw materials were prepared through the carbonization and activation process and applied as electrode in supercapacitor. The biomass carbon ...materials activated under different temperatures were tested by cyclic voltammetry, electrochemical impedance spectroscopy and galvanostatic charge-discharge cycling method. The corn stalk core-derived material activated at 700 °C with the highest specific surface area (2349.89 m2 g−1) has exhibited the maximum specific capacitance of 140 F g−1. Further detailed characterization and theoretical analysis have demonstrated that the corn stalk core derived activated carbon anode material can not only enhance the capacity of supercapacitor but also realize the comprehensive utilization of corn stalks.
Corn stalk core-derived activated carbonaceous anode material was synthesized by a facile method. Its unique porous structure plays an important role in the improvement of electrochemical performance. Display omitted
•We report a high surface carbon anode material derived from corn stalk core via a facile method.•The environment-friendly method has potential application in biomass waste treatment.•The biomass electrode delivers an excellent cycleability with high capacity and superior rate capability.
In this paper, rice husk was selected as raw materials to prepare activated carbon via an effective and facile method. NaOH, as an activator, plays a crucial role in forming the hierarchical porous ...structure in this method. These materials were characterized through X-ray diffraction (XRD), Raman spectroscopy, Nitrogen adsorption-desorption analyses, Scanning electron microscopy (SEM) and Transmission electron microscopy (TEM). The electrochemical properties have varied with the changes of morphology and structure after the activation process. After 100 cycles at a rate of 0.2C, the reversible specific capacity of rice husk-derived activated carbon (denoted as RHAC) stabilized at 448 mAhg−1. In addition, the RHAC electrode delivers an excellent rate capability with the discharge capacities of 652, 477, 363, 242 and 197 mAhg−1 at 0.2C, 0.5C, 1C, 2C, 5C, respectively. Compared with the non-activated materials (denoted as RHC), the significantly improved electrochemical performance of the RHAC could be attributed to the hierarchical porous structure with more edges, defects and the enlarged surface area.
Rice husk-derived activated carbonaceous anode material was synthesized by a facile method. Its unique porous structure plays an important role in the improvement of electrochemical performance. Display omitted
•We report an activated carbon anode material derived from rice husk via a facile method.•This low-cost and environment-friendly method has potential application in biomass waste treatment.•This biomass electrode delivers excellent performances with high capacity and superior rate capability.
Porous carbon materials have been prepared by using natural SiO2 in rice husk as the template. When used as anode for lithium ion battery, it displayed an excellent electrochemistry performance of ...high specific capacity and super coulomb efficiency.
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•Porous carbon material is prepared using natural SiO2 in rice husk as a template.•This carbon material has exhibited excellent specific capacity after 500 cycles.•The coulomb efficiency of porous carbon anode is close to 100%.
Porous carbon anode materials is synthesized by using rice hull natural SiO2 as templates, and the materials with a specific surface area of 332 m2g−1 has possessed micropores, mesopores and macropores microstructure. The materials display a high capacity of 756.9 mAhg−1 after 150 charge-discharge cycles at 0.2C and 620 mAh/g after 600 cycles at 2C, the coulomb efficiency is close to 100%. The excellent performance makes it a promising candidate for high-capacity lithium-ion batteries.
With the increasing demand of the parts with multi-segment curvature, long length, and complex section shape, the required target shape is more and more difficult to meet. In this article, a flexible ...three-dimensional (3D) multi-point stretch bending processing method for a roller die is proposed, and a flexible 3D stretch bending equipment of a roller die is developed. With the application of flexible 3D stretch bending technology of roller dies, the complex 3D parts can be formed at one time with only two degrees of freedom. In order to better evaluate the springback deformation of 3D parts, the total springback process of the flexible 3D stretch bending parts of a roller die is divided into two parts: horizontal bending springback distance and vertical bending springback distance. The springback law of different length profiles is studied by numerical simulation and compared with the experiment. From the perspective of springback, this study analyzes the parts produced by the 3D FSBRD process and studies the influence of different process parameters on springback.
Springback compensation is considered as the best method to reduce springback error. In view of the springback defect of 3D deformed workpiece, a springback compensation method based on variable ...compensation factor is proposed. This method can accelerate the convergence speed of iterative compensation. In this paper, the 3D flexible stretch bending of multi-point roller die technology (3D FSB-MPRD) is introduced firstly, and then, the principle of the springback compensation method based on variable compensation factor is explained. In order to improve the springback compensation accuracy of workpiece, the total springback compensation process is divided into horizontal bending springback compensation and vertical bending springback compensation. Taking the T-shaped profile with variable curvature as the research object, the die surface is optimized and the optimal springback compensation factor is obtained by using numerical simulation after multiple iterations. Finally, the results of springback compensation are compared with the desired shape. And the effectiveness of the springback compensation method based on variable compensation factor is verified by comparing the simulation results with the test results.
We illustrate the SEM and TEM images of porous active carbon using a facile and effective method. In this method, corn stalk core was decomposited and carbonized under an inert gas atmosphere, and ...then activated by KOH solution. The sample surface with many folds has a different degree of pore structure after activated. The main small pore size lies in the 2–10 nm range. The porous activated carbon as lithium ion batteries(LIBs) anodes showed a high reversible capacity of 504 mAg−1 after 100 cycles at 0.2C. The cycling performance of the active carbon anode has been improved significantly. The electrochemical performance of the activated carbon was significantly improved in comparison with that of unactivated carbon, which was due to its multi-scale pore distribution and amorphous structure. In summary, this facile and effective method for the preparation of porous activated carbons offers a new route as powerful application in LIBs.
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•A novel porous activated carbon (AC) derived from corn stalk core is prepared via a facile and effective method.•The activated carbon anode possesses excellent reversible capacity of 504 mAh g−1 after 100 cycles at 0.2C.
A novel mesoporous activated carbon (AC) derived from corn stalk core is prepared via a facile and effective method which including the decomposition and carbonization of corn stalk core under an inert gas atmosphere and further activation process with KOH solution. The mesoporous activated carbon (AC) is characterized by X-ray diffraction (XRD), Raman spectroscopy, scanning electron microscopy (SEM), transmission electron microscopy (TEM) and Brunauer-Emmett-Teller (BET) measurements. These biomass waste derived from activated carbon is proved to be promising anode materials for high specific capacity lithium ion batteries. The activated carbon anode possesses excellent reversible capacity of 504 mAh g−1 after 100 cycles at 0.2C. Compared with the unactivated carbon (UAC), the electrochemical performance of activated carbon is significantly improved due to its mesoporous structure.
In this paper, rotary draw bending (RDB) process is used to bend the rectangular ribbed (日-shaped) section profiles into commercial vehicle anti-collision beams. But the bottom plate of the profile ...will inevitably produce wrinkling defects in the actual processing. Therefore, ABAQUS finite element (FE) software is used to simulate the profile with no mandrel in RDB process to obtain the formation mechanism of the defects. Based on the above result, a novel type of mandrel-novel flexible cores (NFC) is designed. Its innovation is not only perfect for RDB of the rectangular ribbed (日-shaped) section profile but also can play a good role in occasions where the use of ordinary mandrels is limited. All in all, the working occasions are not limited. Moreover, changing the parameters of the mandrel core can achieve any angle bending under the premise of ensuring accuracy, and the cross-sectional distortion is small. Finally, the wrinkling rate at the bending area of the actual anti-collision beam product is measured and calculated, and the result shows that the wrinkling rate
Q
is less than the standard value that defines the presence or absence of wrinkling, which is regarded as no-wrinkling. And there is a good agreement between simulation and experimental results.
High efficient electrocatalytic activity and strong stability to both oxygen reduction reaction (ORR) and oxygen evolution (OER) are very critical to rechargeable Zn-air battery and other renewable ...energy technologies. As a class of promising catalysts, the nanocoposites of transition metal nanoparticles that are encapsulated with nitrogen-doped carbon nanoshells are considered as promising substitutes to expensive precious metal based catalysts. In this work, we demonstrate the successful preparation of high-density cobalt nanoparticles encapsulated in very thin N-doped carbon nanoshells by the pyrolysis of solid state cyclen-Co-dicyandiamide complex. The morphologies and properties of products can be conveniently tuned by adjusting the pyrolysis temperature. Owing to the synergetic effect of hybrid nanostructure, the optimized Co@N-C-800 sample possesses outstanding bifunctional activity for both ORR and OER in alkaline electrolyte. Meanwhile, the corresponding rechargeable zinc-air battery that is based on Co@N-C-800 air cathode also has excellent current density, low charge-discharge voltage gap, high power density, and strong cycle stability, making it a suitable alternative to take the place of precious metal catalysts for practical utilization.
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