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In order to realize sustainable renewable energy supply, large-scale energy storage system is needed to overcome the problem of intermittency of power generation. Vanadium redox flow battery (VRFB) presents the most viable solution but faces the problem of high material cost. In this study, we have established a cost-effective process to prepare vanadium electrolyte for VRFB from an untouched industrialwaste, ammonia slag, by pHcontrol under atmospheric condition (<95°C). The extracted solution changed color during electrolytic reduction as yellow, blue, dark green and purple, matched with the colors ofV5+, V4+, V³+, andV²+, respectively, indicating accurate change of the valences without forming precipitates. Electrolyte prepared from the recycled vanadium showed almost the same charging/discharging performances as the one prepared from commercial V2O5 reagent battery tests during the first several cycles, but degraded rapidly after 16 cycles, caused by impurities that deactivate the negative electrode for the reduction of V³+ to V²+. The miniature VRFB prototype built by employing 3D printing technique showed a much higher performance than the H-cell, indicating the flow cell configuration could help to push up the diffusion limit of vanadium redox by flowing the electrolyte solution through the electrodes, as well as reducing IR loss and water splitting to increase the efficiency. [ABSTRACT FROM AUTHOR]

Electrochemical impedance spectroscopy (EIS) and intensity-modulated photocurrent/voltage spectroscopy (IMPS/IMVS) measurements are carried out to investigate the transport and recombination kinetics in dye-sensitized solar cells (DSSCs) employing three different kinds of ZnO nanoparticles: hexagonal bipyramidal (HBP) with predominantly (102) facets, nanosheets (NS) with predominantly (100) and commercial nanoparticles (MZ) with random facets exposed. The order of recombination resistance MZ > HBP > NS revealed from EIS and IMVS did not coincide with the order NS > MZ > HBP of the open circuit voltage (VOC) of the DSSCs. Chemical capacitance determined by EIS indicated the most negatively lying conduction band edge for NS, that accounts for the higher VOC despite lower recombination resistance. On the other hand, transport resistance from EIS and electron transit time from IMPS both indicate faster electron transport for well-crystallized hydrothermally synthesized HBP and NS than for the randomly structured commercial MZ. That of MZ, however, was still sufficiently fast compared to the electron lifetime to ensure a good collection efficiency, leading to almost constant short circuit current density (JSC) among MZ, NS and HBP. [ABSTRACT FROM AUTHOR]

Taichi Chuan was previously shown to benefit physical health, but the results were inconsistent. The main reason is that the mechanism is not clear and may be interpreted differently. In this systematic review, we analyzed the data obtained from various randomized controlled trials to identify the effectiveness of Taichi Chuan and the mechanism by which it improves the physical health of adults. We systematically searched various databases, including PubMed, Web of Science, Scopus, Embase, EBSCO Host, Science Direct, CNKI, Wan-Fang, and VPCS, and obtained 1448 articles for review. The articles were selected following the PICO eligibility criteria. We performed a systematic review and meta-analysis to interpret the results of the different studies. We included 16 studies in the systematic review. Six of them were of very high quality, ten were of acceptable quality. Overall, the results showed that Taichi Chuan is beneficial to physical fitness, but not all indices supported this statement. Specifically, the effects were significant on Balance (ES = − 0.33; P = 0.02), BMI (ES = − 0.83; P < 0.00001), body fat (ES = − 0.45; P < 0.00001), and vital capacity (ES = 23.39; P = 0.01). However, there were no significant effects on systolic blood pressure (ES = 0.07; P = 0.94) and diastolic blood pressure (ES = 0.03; P = 0.97). We found sufficient high-quality evidence to suggest that Taichi Chuan affects balance, BMI, body fat, vital capacity, and flexibility (sit-reach) in adults. The mechanism can be explained by low posture (balance) and moderate intensity of Taichi Chuan. However, no study has explained how to maintain concentration while keeping a dynamic low posture, which made it difficult to validate the finding that Taichi Chuan can reduce sympathetic tension under stress. In this study, we assumed that relaxation methods, which work on the central nervous system that links the body and the mind, might be the key explanation. However, further studies based on scientific, replicable methods need to be performed to confirm our findings. • TCC'S tranquil pace constrains exercise intensity, leading to less favorable findings in previous research studies. • This article systematically reviews Chinese and English TCC trials, assessing its impact on fitness in adults and identifying theoretical gaps. • This study links exercise effects to dynamic low postures and moderate exercise intensity. • The neglect of relaxation theory in TCC intervention may be the main reason for the insufficient physical fitness effective. • Unlocking TCC's potential entails systematic integration of neurophysiology and neuropsychology to probe relaxation theory's mind-body mechanisms.. [ABSTRACT FROM AUTHOR]

We present fabrication and characterization of flexible high voltage dye-sensitized solar cells (DSSCs) by screen printing of porous ZnO photoelectrode to power up IoT (Internet of Things) nodes to substitute batteries. Combination of triphenylamine based organic dye, D35, and [Co(bpy)3]2+/3+ (bpy = 2,2'-bipyridine) redox electrolyte achieved high voltages approaching 1 V, owing to strong rectification of charge transfer processes by passivation of the ZnO surface by the adsorbed D35 layer. The system, however, suffered from limited diffusion of the Co complex redox couple within the porous photoelectrode, causing saturation of photocurrent and poor fill factor to limit the overall conversion efficiencies under high light illumination. The current/voltage linearity was improved by optimizing the thickness of porous ZnO layer and by use of low viscosity electrolyte solvent. The highest conversion efficiencies we obtained were 3.73 and 2.63% for the cells employing F-doped SnO2 (FTO) coated glass and indium tin oxide (ITO) coated poly-ethylenenaphthalate (PEN) film substrates, respectively. [ABSTRACT FROM AUTHOR]

The growing population density in cities requires urban transportation to meet the travel needs of citizens fast and accurately. Therefore, the correct prediction of daily passenger flow in urban subway transportation is of great practical importance for rationalizing the traffic arrangement and safely responding to unexpected passenger flow. This work builds a Bayesian spatial–temporal model for predicting station occupancy. The proposed one provides point estimations of daily passenger flow, a reliable assessment of their uncertainty, and the possibility of understanding traffic features. It also provides a prediction accuracy that meets the standards of the Beijing Metro enterprise. The model discussed in this paper is in force at Beijing Metro Group Ltd to programme daily train schedules. [ABSTRACT FROM AUTHOR]

Backgrounds: The level of job satisfaction among clinical research associates (CRAs) is of importance because it may affect CRAs' retention, turnover, and then further affect the quality of clinical trials. Objectives: The objectives of this study were to (1) examine the level of job satisfaction among CRAs in China and (2) explore the association between CRAs' demographic and work-related characteristics and their job satisfaction. Methods: A Chinese CRA job satisfaction questionnaire was developed to measure CRAs' attitudes in relation to their job. The questionnaire contained 6 subcomponents, including work content, work reward, supervisors, coworkers, investigators, and organization administration. Then an anonymous cross-sectional web-based survey was conducted among CRAs in China. Results: 465 valid questionnaires were received (93% response rate). The overall job satisfaction of Chinese CRAs was moderate. As for the individual subcomponents, coworkers ranked the highest and work reward ranked the lowest. The female group was more satisfied with investigators than were the male group. Different scores with supervisors were seen among age groups. Different scores with overall satisfaction, work reward, and organizational administration were seen among geographic location groups and also among company type groups. There were no significant differences in job satisfaction based on marital status, education level, and working position of the respondents. Conclusions: Chinese CRAs were moderately satisfied with their job. They were most satisfied with coworkers and most dissatisfied with work reward. Further, Chinese CRAs' job satisfaction levels were more related with work-related characteristics, including geographic location and company type. [ABSTRACT FROM AUTHOR]

The reaction mechanism for oxygen reduction reaction (ORR) on Si-doped divacancy graphene is investigated by employing the density functional method. Our results show that all of the possible ORR elementary steps and charge transfer could take place within a small active region around the Si atom and its adjacent four carbon atoms. Among the possible reaction pathways, O2 dissociation and OOH hydrogenation into O + H2O are the most favorable pathways kinetically. The rate-determining step is the O atom hydrogenation into OH with an energy barrier of 1.13 eV. This value is similar to 1.11 eV for the single layer SiC and 1.18 eV for SiC2. Si-doped divacancy graphene has good tolerance against CO poisoning compared with Pt (111). Thus, Si-doped divacancy graphene could be a promising metal-free catalyst for ORR. [ABSTRACT FROM AUTHOR]

The purpose of this study was to investigate the underlying mechanism(s) of the total alkaloids (TA) from Mahonia bealei in treating pyloric ligation-induced gastric ulcers in rats. Animals were sacrificed after 19 h of the ligation. Gastric acid, peptic activities, mucin levels, H+/K+-ATPase activities and the gastrin level were analyzed. To improve the accuracy of the observations, IPP 6.0 software was introduced to measure the area of ulcer. TA (18.56 mg/kg/day, i.g.) showed an antiulcer effect by significantly decreasing the gastric ulcer areas (11.28 mm²) compared with model group (26.36 mm²). The TA ulcer inhibition ratio was 57.2%, compared with the effect of the positive control, omeprazole (62.96%). The results also showed that TA had a significant effect in inhibiting the release of H+/K+-ATPase, reducing the content of gastrin and decreasing gastric acidity on experimental animals. However, the TA had no significant effects on gastric mucus secretion and pepsin activity. Data indicated that TA had gastric ulcer protective effects by modulating the H+/K+-ATPase activity and gastrin level. TA has a potential to be developed as a pharmacological agent for the treatment of gastric ulcers. [ABSTRACT FROM AUTHOR]

Abstract: Tower-wire model is established by use of ANSYS/LS-DYNA under the background of a long-distance transmission project. The dynamic responses are numerically simulated in the condition of transmission lines icing. Results show that impact effections of transmission towers on broken-line span and non-broken-line span nearly induced by icing and broken wires are both prominent. Stresses and displacements responses are distinct in boken-line span,and responses weaken gradually with the distance increasing from broken-point. It provides a reference for dynamic analysis of transmission tower-line system. [Copyright &y& Elsevier]