Preparation of Porous Activated Carbons for High Performance Supercapacitors from Taixi Anthracite by Multi-Stage Activation.

Coal-based porous materials for supercapacitors were successfully prepared using Taixi anthracite (TXA) by multi-stage activation. The characterization and electrochemical tests of activated carbons (ACs) prepared in different stages demonstrated that the AC from the third-stage activation (ACIII) shows good porous structures and excellent electrochemical performances. ACIII exhibited a fine specific capacitance of 199 F g-1 at a current density of 1 A g-1 in the three-electrode system, with 6 mol L-1 KOH as the electrolyte. The specific capacitance of ACIII remained 190 F g-1 even despite increasing the current density to 5 A g-1, indicating a good rate of electrochemical performance. Moreover, its specific capacitance remained at 98.1% of the initial value after 5000 galvanostatic charge-discharge (GCD) cycle tests at a current density of 1 A g-1, suggesting that the ACIII has excellent cycle performance as electrode materials for supercapacitors. This study provides a promising approach for fabricating high performance electrode materials from high-rank coals, which could facilitate efficient and clean utilization of high-rank coals.

Activation of corticotropin-releasing factor neurons and microglia in paraventricular nucleus precipitates visceral hypersensitivity induced by colorectal distension in rats.

Visceral hypersensitivity is a major contributor to irritable bowel syndrome and other disorders with visceral pain. Substantial evidence has established that glial activation and neuro-glial interaction play a key role in the establishment and maintenance of visceral hypersensitivity. We recently demonstrated that activation of spinal microglial toll-like receptor 4 (TLR4)/myeloid differentiation factor 88 (MyD88)/nuclear factor κB (NF-κB) signaling facilitated the development of visceral hypersensitivity in a rat model developed by neonatal and adult colorectal distensions (CRDs). Hypothalamic paraventricular nucleus (PVN) plays a pivotal role in the pathogenesis of chronic pain. In this study, we examined the mechanism by which microglia and neurons in PVN establish and maintain visceral hypersensitivity and the involvement of TLR4 signaling. Visceral hypersensitivity was precipitated by adult colorectal distension (CRD) only in rats that experienced neonatal CRDs. Visceral hypersensitivity was associated with an increase in the expression of c-fos, corticotropin-releasing factor (CRF) protein and mRNA in PVN, which could be prevented by intra-PVN infusion of lidocaine or small interfering RNA targeting the CRF gene. These results suggest PVN CRF neurons modulate visceral hypersensitivity. Adult CRD induced an increase in the expression of Iba-1 (a microglial marker), TLR4 protein, and its downstream effectors MyD88, NF-κB, as well as proinflammatory cytokines tumor necrosis factor-α (TNF-α) and interleukin-1ß (IL-1ß) only in rats that experienced neonatal CRDs. Intra-PVN infusion of minocycline, a nonselective microglial inhibitor, attenuated the hyperactivity of TLR4 signaling cascade, microglial activation, and visceral hypersensitivity. Taken together, these data suggest that neonatal CRDs induce a glial activation in PVN. Adult CRD potentiates the glial and CRF neuronal activity, and precipitates visceral hypersensitivity and pain. TLR4 signaling and proinflammatory cytokines TNF-α and IL-1ß may participate in neuro-glial interaction during the pathogenesis of visceral hypersensitivity.

N/O co-doped porous interconnected carbon nanosheets from the co-hydrothermal treatment of soybean stalk and nickel nitrate for high-performance supercapacitors.

Porous interconnected carbon nanosheets (PICNs) with high electrochemical performance were prepared by doping urea and a co-hydrothermal precursor derived from soybean stalk (SS) and nickel nitrate. The specific surface area and average pore diameter of the as-synthesized PICNs are 2226.29 m2 g-1 and 1.89 nm, and their N and O contents are 5.08% and 9.4%, respectively, which is beneficial for increasing pseudocapacitance. Furthermore, the doping of the metal Ni increases the graphitization degree of the PICNs and promotes the conversion of pyridine-N to graphitized-N. Therefore, the PICNs possess a high specific capacitance of 407 F g-1 at a current density of 0.5 A g-1, a high capacitance retention of 78.62% even at 20 A g-1, and an outstanding cycling stability (over 93% retention rate after 10,000 charge/discharge cycles). Moreover, an energy density of 36.11 W h kg-1 is achieved at a power density of 517.8 W kg-1 during a two-electrode system test, and a retention rate of 87.5% is obtained after 10,000 cycles. This co-hydrothermal treatment as well as nitrogen-doping approach for preparing porous interconnected carbon from SS not only represents an alternative strategy for carbon-based supercapacitor materials but also provides a new option for the utilization of waste SS.

Small-Conductance Ca2+-Activated K+ Channel 2 in the Dorsal Horn of Spinal Cord Participates in Visceral Hypersensitivity in Rats.

Visceral hypersensitivity is a highly complex and subjective phenomenon associated with multiple levels of the nervous system and a wide range of neurotransmission. The dorsal horn (DH) in spinal cord relays the peripheral sensory information into the brain. Small conductance Ca2+-activated K+ (SK) channels regulate neuronal excitability and firing by allowing K+ to efflux in response to increase in the intracellular Ca2+ level. In this study, we examined the influence of SK2 channels in the spinal DH on the pathogenesis of visceral hypersensitivity induced by colorectal distension (CRD) in rats. Electrophysiological results showed that rats with visceral hypersensitivity presented a decrease in the SK channel-mediated afterhyperpolarization current (IAHP), and an increase in neuronal firing rates and c-Fos positive staining in the spinal DH. Western blot data revealed a decrease in the SK2 channel protein in the membrane fraction. Moreover, intrathecal administration of the SK2 channel activator 1-EBIO or CyPPA alleviated visceral hypersensitivity, reversed the decrease in IAHP and the increase in neuronal firing rates in spinal DH in rats that experienced CRD. 1-EBIO or CyPPA effect could be prevented by SK2 channel blocker apamin. CRD induced an increase in c-Fos protein expression in the spinal DH, which was prevented by 1-EBIO. Together, these data suggest that visceral hypersensitivity and pain is associated with a decrease in the number and function of membrane SK2 channels in the spinal DH. Pharmacological manipulation of SK2 channels may open a new avenue for the treatment of visceral hypersensitivity and pain. Highlights: -Neonatal colorectal distension induced visceral hypersensitivity in rats.-Visceral hypersensitivity rats presented a decrease in afterhyperpolarization current (IAHP) and membrane SK2 channel protein in the spinal dorsal horn.-Visceral hypersensitivity rats presented an increase in neuronal firing rate in the spinal dorsal horn.-Intrathecal administration of SK2 channel activator 1-EBIO or CyPPA prevented visceral hypersensitivity and decrease in IAHP.

Preparation of porous carbon spheres from 2-keto-l-gulonic acid mother liquor by oxidation and activation for electric double-layer capacitor application.

A novel strategy is proposed for the increase of specific surface area (SSA) of porous carbon sphere (PCS) by oxidation and activation. 2-keto-l-gulonic acid mother liquor (GAML) as a high-pollution waste has a relatively high value of reutilization. For its high value-added utilization, GAML is used as the precursor for preparation of PCS as carbon-based electrode materials for electric double-layer capacitor. PCS is prepared by hydrothermal carbonization, carbonization and KOH activation, and Fe(NO3)3 9H2O is used as an oxidizing agent during carbonization. The as-prepared PCS has excellent porosity and high SSA of 2478 m2 g-1. Meanwhile, the pore structure of PCS can be controlled by the adjustment of carbonization parameters (carbonization temperature and the loading of Fe(NO3)3 9H2O). Besides, the SSA and specific capacitance of PCS can be increased remarkably when Fe(NO3)3 9H2O is added in carbonization. The specific capacitance of PCS can reach 303.7 F g-1 at 40 mA g-1. PCSs as electrode material have superior electrochemical stability. After 8000 cycles, the capacitance retention is 98.3% at 2 A g-1. The electric double-layer capacitance of PCS is improved when CS is carbonized with Fe(NO3)3 9H2O, and the economic and environmental benefits are achieved by the effective recycle of GAML.