It is a long-lasting challenge to design and synthesize electric double-layered electrode materials with suitable graphitization strength, simultaneously working to achieve a high capacitance for electrochemical capacitors. In our work, starch-based porous carbons (SPCs) are obtained via carbonization and mature KOH chemical activation. The prepared materials have a superior specific capacitance of 397, 372, and 337 F g −1 corresponding to SPC-5, SPC-15, and SPC-25 (SPC-x, x represents the starch particle size), as well as a distinguished cycling stability of 97% capacity retention over 20 000 cycles in KOH electrolyte. In addition, in 6 M KOH electrolyte, SPC-5 exhibits a superior energy density of 22.59 W h kg −1 when the power density is 148 W kg −1 . This is mainly due to its suitable graphitization strength and particle size. Biomass is used with different amylopectin content to control the degree of graphitization of carbon materials. The strategy demonstrates a way to fabricate a reasonable graphitized carbons derived from biomass with improved capacitance, which is critical for a broad range of devices for the field of energy storage.

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Proton exchange membranes are widely used in fuel cells for directly converting chemical energy into electrical energy. Commercially successful perfluorosulfonic acid membranes do not have the ability of proton conduction under dry conditions. Owing to the advantages of simplified thermal and water management, anhydrous proton conductive materials are appealing. Herein, a novel liquid crystalline composite membrane is prepared by a solution cast method for anhydrous proton conduction at elevated temperatures. Linear polyvinyl alcohol acts as “main chain”, and mesomorphic imidazolium hydrogen sulfate molecules containing a rigid mesogen act as “side chains” to form a side-chain like liquid crystalline composite. Furthermore, the composite membrane can be macroscopically aligned through unidirectionally shearing to promote anhydrous proton conduction. The composite exhibits a conductivity of 2.8 × 10–4 S cm–1 at 150 °C and a tensile strength up to 6.7 MPa. The ionic liquid crystalline composite offers a facile way to achieve ordered molecular arrangement in membranes for proton conduction at elevated temperatures.

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Type 1 diabetes mellitus (T1DM) is a chronic disease represented by insulin-causing pancreatic β-cell disruption and hyperglycemia. Therefore, it is necessary to establish a variety of animal models of diabetes to study the pathogenesis and pathophysiology of it. However, there are few reports on the use of beagle dogs to establish an animal model of type 1 diabetes. This study aimed to explore a simple and feasible modeling method to establish a long-term and stable type 1 diabetes model in beagle dogs. Forty adult beagle dogs were randomly divided into control group and model group. After 24 h of fasting, streptozotocin (20 mg/kg) and alloxan (20 mg/kg) were injected through the cephalic vein. The second intravenous injection was given on the 4th day after the first injection. Insulin release testing was performed on the 7th day after the last intravenous injection. Fasting blood glucose and body weight were recorded monthly. Four months after the last injection, the serum fructosamine content and the ratio of glycated hemoglobin were detected. Then, the pancreatic tissue was harvested for histopathological examination. The results showed that the level of fasting blood glucose of the 16 dogs in the model group was consistently higher than 11.1 mmol/L for 4 consecutive months. Moreover, compared with the control group, the insulin release curve of the model group was flat with no increase. The body weight of the model group was significantly reduced, and the ratios of blood glucose, fructosamine, and glycosylated hemoglobin were significantly higher than those in the control group. Meanwhile, histopathological examination of the pancreas showed that the islet beta cells appeared to have vacuoles or even necrosis. In the model group, pancreatic β-cells were damaged and insulin release was reduced. These results suggest that the above modeling methods can induce long-term and stable type 1 diabetes models in beagle dogs.