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It is imperative to design and manufacture electrocatalysts towards oxygen reduction reaction (ORR) and oxygen evolution reaction (OER) for popularization of rechargeable Zn-air batteries. Herein, FeNi alloy confined in N-doped carbon nanosheets (FeNi@NCSs) was harvested via a facile complexation-pyrolysis strategy from the mixture of guanine and metal chlorides. After strictly exploring the pyrolysis temperature and metal types, the resulted FeNi@NCSs showed greatly improved performances on both the ORR (onset potential of 0.93 V and half-wave potential of 0.84 V) and OER (overpotential of 318 mV at 10 mA cm

Design of advanced carbon nanomaterials with high-efficiency oxygen reduction reaction (ORR) and oxygen evolution reaction (OER) activities is still imperative yet challenging for searching green and renewable energies. Herein, we synthesized ultrafine FeNi/(FeNi)9S8 nanoclusters encapsulated in nitrogen, sulfur-codoped graphitic carbon nanosheets (FeNi/(FeNi)9S8/N,S-CNS) by coordination regulated pyrolyzing the mixture of the metal precursors, dithizone and g-C3N4 at 800 °C. The as-prepared FeNi/(FeNi)9S8/N,S-CNS exhibited distinct electrocatalytic activity and stability for the ORR with positive onset (Eonset) and half-wave (E1/2) potentials (Eonset = 0.97 V; E1/2 = 0.86 V) and OER with the small overpotential (η = 283 mV) at 10 mA cm-2 in the alkaline media, outperforming commercial Pt/C and RuO2 catalysts. This research provides some constructive guidelines for preparing efficient, low-cost and stable nanocatalysts for electrochemical energy devices.

Currently, it is critical but a tricky point to develop economical, high-efficiency, and durable non-precious metal electrocatalysts towards oxygen reduction and oxygen evolution reaction (ORR/OER) in rechargeable Zn-air batteries. Herein, N, Mn-codoped three-dimensional (3D) fluffy porous carbon nanostructures encapsulating FeCo/FeCoP alloyed nanoparticles (FeCo/FeCoP@NMn-CNS) are prepared by one-step pyrolysis of the metal precursors and polyinosinic acid. The optimized hybrid nanocomposite (obtained at 800 °C, named as FeCo/FeCoP@NMn-CNS-800) exhibits outstanding catalytic performance in the alkaline electrolyte with a half-wave potential (E1/2) of 0.84 V for the ORR and an overpotential of 325 mV towards the OER at 10 mA cm−2. Impressively, the FeCo/FeCoP@NMn-CNS-800-assembled rechargeable Zn-air battery presents an open-circuit voltage of 1.522 V (vs. RHE), a peak power density of 135.0 mW cm−2, and long-term durability by charge-discharge cycling for 200 h, surpassing commercial Pt/C + RuO2 based counterpart. This work affords valuable guidelines for exploring advanced bifunctional ORR and OER catalysts in rational construction of high-quality Zn-air batteries.

Rational development of low-cost, durable and high-performance bifunctional oxygen catalysts is highly crucial for metal-air batteries. Herein, transition metal alloyed FeCo nanoparticles (NPs) embedded into N-doped honeycombed carbon (FeCo@N-HC) was efficiently prepared by a one-step carbonization method in the existence of NH4Cl and citric acid. Benefiting from the honeycomb-like architectures and the synergistic effects of the FeCo alloy with the doped-carbon matrix, the as-synthesized FeCo@N-HC exhibited outstanding oxygen reduction reaction (ORR) with the more positive onset potential (Eonset = 0.98 V vs. RHE) and half-wave potential (E1/2 = 0.85 V vs. RHE), coupled with outstanding oxygen evolution reaction (OER) with the lower overpotential (318 mV) at 10 mA cm−2. Besides, the home-made Zn-air battery has the larger power density of 144 mW cm−2 than Pt/C + RuO2 (80 mW cm−2). This research offers some valuable guidelines for constructing robust oxygen catalysts in clean energy storage and conversion technologies.

The traditional Chinese medicine of Qingxin Kaiqiao Recipe (QKR) is effective in the treatment of Alzheimer’s disease (AD). This study aims to investigate whether QKR improves the cognitive ability and takes neuroprotective effect on APP/PS1 double transgenic mice via the PI3K/Akt pathway. APP/PS1 double transgenic mice were randomly divided into a model, donepezil-treated, or QKR-treated group (L-QKR: 4.75 mg/kg/d, M-QKR: 9.5 mg/kg/d, and H-QKR: 19 mg/kg/d, respectively). Wild-type C57/BL6J mice were used as the control group. Morris water maze (MWM) was used to test the ability of spatial navigation and memorization; terminal deoxynucleotidyl transferase-mediated dUTP nick end-labelling (TUNEL) assay was applied to test the apoptosis; amyloid protein granule deposition was detected via Methenamine silver staining; Western blot (WB) analysis, immunohistochemistry, and RT-PCR were applied to measure the expression of Aβ and corresponding indicators of the PI3K/Akt pathway. Compared with the model group, QKR significantly relieved the cognitive impairment, reduced the deposition of senile plaques, decreased the expression of GSK-3α and Aβ, and increased the expression of p-PI3K, p-Akt, and IDE. In addition, the number of TUNEL-positive cells decreased after treatment using QKR. The current study proved that QKR, especially at the high dose tested, exerted a protective effect on improving learning and memory, inhibiting apoptosis, and reducing the process of pathological degeneration in the hippocampus of AD mice.

Design of advanced carbon nanomaterials with high-efficiency oxygen reduction reaction (ORR) and oxygen evolution reaction (OER) activities is still imperative yet challenging for searching green and renewable energies. Herein, we synthesized ultrafine FeNi/(FeNi)

For development of green and sustainable energy, it is of importance to search highly efficient and low-cost electrocatalysts of oxygen reduction reaction (ORR) in energy conversion devices. Herein, CoFe alloyed nanocrystals embedded in N-doped bamboo-like carbon nanotubes (CoFe@NCNTs) were facilely synthetized by one-step co-pyrolysis with the mixture of triamterene, metal chlorides and graphitic carbon nitride (g-C3N4). The resultant CoFe@NCNTs exhibited excellent ORR activity with the positive shifts in the onset potential (Eonset = 0.97 V) and half-wave potential (E1/2 = 0.88 V), outperforming commercial Pt/C (Eonset = 0.96 V; E1/2 = 0.84 V). Compared to metal organic frameworks (MOFs)-based strategy for synthesis of low-cost carbon-based ORR catalysts, this method is simple and convenient, coupled by avoiding the complicated synthesis of MOFs and its ligands. This work provides a promising route to fabricate advanced transition-metal-based carbon catalysts in the researches correlated with energy conversion devices.

Transition metal-based nitrogen-doped carbon (M-N

In great demand of clean energy conversion devices, ideal electrode materials are expected to have low cost, high efficiency, and long durability in contrast with the benchmarked catalysts (e.g. Pt- and RuO2-based materials) for reversible oxygen electrocatalysis. Herein, a convenient and general strategy is presented for preparation of high-yield FeCo-nitrogen-carbon nanotubes with porous and hollow structure (FeCo-NCNTs), in which the chlorinated metals were initially chelated with 2,4,6-tris(2-pyridyl)-s-triazine (TPTZ), followed by ultimate pyrolysis and acid treatment. The resulting FeCo-NCNTs exhibited outstanding catalytic property for oxygen reduction reaction (ORR, E1/2 = 0.90 V) and oxygen evolution reaction (OER, 320 mV of overpotential at 10 mA cm−2) in alkaline surroundings. Besides, the density functional theory (DFT) calculations revealed that the porous structure created abundant active sites and active Fe-centered FeCo sites greatly reduced the OOH* energy barrier to promote the ORR. Moreover, the FeCo-NCNTs based rechargeable Zn–air battery exhibited high open circuit voltage (1.55 V), large output power density (148 mW cm−2), and robust stability (115 h, 345 cycles), surpassing the mixed Pt/C + RuO2 derived battery. Furthermore, the alternative FeNi-NCNTs and FeMn-NCNFs systems also displayed superior performances in the same environment. This strategy offers a new avenue for rational design of advanced metal-nitrogen-carbon materials with high electrocatalytic performances.

Three new isoflavone glucosides, kudonol A−C (1–3), two new ester derivatives of phenylpropanoid, kudolignan A and B (4–5) and five known compounds, (−)-maackiain (6), neoliquiritin (7), methyl 4-coumarate (8), methyl ferulate (9) and (+)-wikstromol (10), were isolated from an extract of dried seeds of the traditional Chinese medicinal plant Sophora alopecuroides L. Their structures were established by NMR and HRESIMS data analyses. The monosaccharide part’s configuration of isoflavone glucosides was confirmed by acid hydrolysis and analyzed by a JAsco OR-4090 chiral detector, comparing it to standard substance D-glucose. The cytotoxicity effects against HeLa, Hep3B, MCF-7 and H1299 cells were tested by CCK-8 assay.

Cyanogel, a novel inorganic polymeric hydrogel, is constituted by chlorometallates and transition-metal cyanometallates, which is thought as fascinating and promising precursor to produce highly alloyed materials with stereochemical structures. In this review, the properties, synthesis methods, and electrochemical applications of the cyanogel and its derivates are systematically discussed. With intrinsic properties such as 3D interconnected backbones, uniform distributions of metals at atomic level, and porous structures, the cyanogel-derived materials exhibit superior activities and stabilities. During the synthesis process, the skeleton of cyanogel serves as soft template for generating metal structures without any surfactant. Due to the versatility and tunability of cyanogels, their derivatives not only provide foreseeable opportunities for preparation of highly efficient nanomaterials in electrocatalytic reactions, but also broaden their practical applications in energy-related devices such as fuel cells, water splitting electrolyzers, metal-air batteries, energy storage batteries, and supercapacitors. Through this review, we aim to provide valuable guidelines for constructing highly effective materials in practice.

Numerous studies have been focused on renewable energy conversion devices (e.g. fuel cell and Zn-air battery) to mitigate the climate changing and serious environmental degradation. Herein, hydrogel derived FeCo/FeCoP embedded in N, P-doped three-dimensional porous carbon framework (FeCo/FeCoP@NP-CF) was prepared by the high-temperature pyrolysis and subsequent acid-etching. Polyacrylamide (PAM) would absorb water here to form hydrogel and act as the C and N sources, which is conducive to capture and in-situ reduce metal ions. The hybrid porous carbon framework had interconnection, highly open structures and molecular accessible hierarchical surfaces. The resultant FeCo/FeCoP@NP-CF displayed remarkable oxygen reduction reaction (ORR) characteristics with a more positive half-wave potential (E1/2) of 0.85 V in 0.1 M KOH electrolyte, surpassing commercial Pt/C (E1/2 = 0.84 V). This work offers some valuable guidelines for synthesis of non-noble metal catalysts in energy technologies.

To assess the long-term use of L-dopa alone vs L-dopa-sparing therapy, as initial treatment, provides the most efficient long-term control of symptoms and best quality of life for people with early Parkinson's disease (PD). PubMed; Google scholar; Cochrane Central Register of Controlled Trials and the Web of Science were searched for randomised, placebo-controlled trials (RCTs) on L-dopa alone and L-dopa sparing as initial treatment in early PD patients. We used a random effects model rather than a fixed effects model because of this takes into account heterogeneity between multi-studies. Eleven RCTs were included. The results showed that L-dopa alone could evidently improve the UPDRS part I (p = 0.005), part II (p < 0.0001), part III (p < 0.0001) and UPDRS total score (p = 0.004) compared with L-dopa-sparing therapy in PD patients. Meanwhile, a reduced risk of dyskinesia (p < 0.0001, RR = 1.88, 95 % CI 1. 37-2.59) and wearing-off phenomenon (p < 0.00001, RR = 1.36, 95 % CI 1. 20-1.55) in patients treated initially with L-dopa-sparing therapy compared to L-dopa has been consistently reported. What is more, we found more patients on aL-dopa-sparing therapy were more than triple as likely to discontinue treatment prematurely due to adverse events than L-dopa treatment patients (43.7 vs 15.8 %). L-Dopa alone is the most effective medication available for treating the motor symptoms of PD patients, despite the greater incidence of involuntary movements. Meanwhile, more patients on dopamine agonists or MAOBI were more likely to discontinue treatment prematurely than L-dopa alone treatment patients within the long follow-up period.

Chromium tungsten nitride (CrWN) films were deposited on silicon substrates using a d.c. magnetron reactive co-sputtering technique equipped with 45° dual guns of Cr and W targets. The morphology and microstructure of the films were investigated by scanning electron microscopy (SEM), X-ray diffraction (XRD), high resolution transmission electron microscopy (HRTEM), and electron probe micro-analyses (EPMA). The mechanical and tribological properties were evaluated using a nanoindentor and a conventional ball-on-disk tribometer, respectively. The as-deposited films have nanocomposite microstructure which CrN is the main crystalline constituent inside. The nanocomposite CrWN films exhibit a low surface roughness (Ra

Deep brain stimulation (DBS) is the surgical procedure of choice for patients with advanced Parkinson disease (PD). We aim to evaluate the efficacy of GPi (globus pallidus internus), STN (subthalamic nucleus)-DBS and medical therapy for PD. We conducted a systematic review and multiple-treatments meta-analysis to investigate the efficacy of neurostimulation and medical therapy for PD patients. Sixteen eligible studies were included in this analysis. We pooled the whole data and found obvious difference between GPi-DBS versus medical therapy and STN-DBS versus medical therapy in terms of UPDRS scores (Unified Parkinson’s Disease Rating Scale). Meanwhile, we found GPi-DBS had the similar efficacy on the UPDRS scores when compared with STN-DBS. What is more, quality of life, measured by PDQ-39 (Parkinson’s disease Questionnaire) showed greater improvement after GPi-DBS than STN-DBS. Five studies showed STN-DBS was more effective for reduction in medication than GPi-DBS. Overall, either GPi-DBS or STN-DBS was an effective technique to control PD patients’ symptoms and improved their functionality and quality of life. Meanwhile, the UPDRS scores measuring parkinsonian symptoms revealed no significant difference between GPi-DBS and STN-DBS. STN-DBS was more effective for reduction in medication than GPi-DBS. Alternatively, GPi-DBS was more effective for improving the PDQ-39 score than STN-DBS.

Copper and 2024 aluminum alloy were melt-infiltrated into porous β-SiC to form SiC/Cu and SiC/Al composites. The porous β-SiC was prepared using Moso bamboo as the bio-template and had structural characteristics of bamboo. The Cu infiltration occurred as low as 1100°C and became significant at 1200°C. After infiltration at 1300°C for 4 h, there was still ~5 % of residual porosity. For the composites with low degree of metal infiltration, the samples fractured like the bamboo-structured porous SiC. For the composites with high degree of infiltration, the sample behaved like monolithic copper. In the infiltration of Al alloy, infiltration occurred at 900°C. Higher Infiltration temperatures would result in significant formation of Al4C3, which gradually decomposed in air.

The objective of this meta-analysis was to evaluate the effects of repetitive transcranial magnetic stimulation (rTMS) for the treatment of depression in patients with Parkinson disease in order to arrive at qualitative and quantitative conclusions about the efficacy of rTMS. We included randomized controlled trials examining the effects of rTMS compared with sham-rTMS or selective serotonin re-uptake inhibitors (SSRIs). The quality of included studies was strictly evaluated. Data analyses were performed using the RevMan5.1 software. Eight studies including 312 patients met all inclusion criteria. The results showed that rTMS could evidently improve the HRSD score compared with sham-rTMS (p

Photocatalytic oxidation of aqueous pollutants by semiconductor photocatalysts was found efficient. The overall process by which the heterogeneous photocatalysis proceeds includes: the sequence of the adsorption of reactants, surface reaction and the desorption of final products. As a result, factors such as, the presence of oxygen concentration, pH values of the aqueous solution, pore properties for photocatalyst particles all determine the rate of photodegradation. This study is to concentrate on the photocatalytic mechanisms of the intrinsic reaction occurred on the photocatalysts and the adsorbed dye in air atmosphere. Additionally, the photocatalytic activities of adsorbed dyes prepared under different pH values were also examined and the solid-state results were compared with the aqueous systems at the same pH conditions. Dark adsorption experiments at different pH conditions showed that the saturation amount of dyes adsorbed on the catalysts differs significantly. However, the solid-state photodegradation rates of adsorbed dyes on TiO 2 at various pH values only showed slightly different, which is opposite to the results obtained from the aqueous systems. This evidence reveals that the external and internal mass transport processes are rate-controlling steps that restricted the photodegradation reaction of aqueous dyes at different pH conditions. Furthermore, this investigation supports a proposed direct photocatalytic mechanism for aqueous systems that the photocatalytic oxidation always begins with the adsorption process and the adsorbed dye will then be attacked by the excited hole–electron pairs and hydroxyl radicals from TiO 2 surface to produce final products.

This chapter presents an LLC resonant converter with constant frequency. Since LLC resonant converters possess the advantages of high efficiency and low electromagnetic interference, they are widely used in many applications. However, the EMI filter design becomes more complex because of the variable-frequency operation of LLC resonant converter. Therefore, in this chapter, a circuit configuration of a buck converter cascade an LLC resonant converter, buck-fed LLC resonant converter, is proposed to complete constant-frequency operation and simplify the EMI filter design. The buck converter is applied in the proposed converter as the input source for the LLC resonant converter. In addition, by adjusting the output voltage of the buck converter, the output regulation and constant-frequency operation of the proposed converter can be achieved. Finally, a prototype of the buck-fed LLC resonant converter with input voltage 380–400 V and output 24 V/10 A is implemented. The experimental results demonstrate the feasibility of the proposed converter.

Recently, Peyravian and Jeffries proposed an efficient password authentication scheme with key agreement, which utilizes no extra tokens and freely updates account numbers and passwords for users. Unfortunately, due to the fact that the integrity is not well protected, it is still vulnerable to the fatal weaknesses. To overcome these security flaws, we propose an enhanced version with novel architecture. Our proposed scheme not only processes the merits that such token-free based schemes have, but also establishes multiple session keys in each session. Moreover, our proposed scheme does not lead heavy burden for users and is easier to implement than the previously similar ones.