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Designing and developing composites with excellent mechanical, friction, and durability properties at low cost has long been highly desirable for the applications of friction materials. Herein, we employed a cost-effective method to obtain bio-based silica (RHC-SiO2) from gasified rice husk carbon (RHC). Subsequently, inspired by the characteristics of RHC-SiO2 and its hardening process, we report a simple and efficient so-called “hybrid pressing and sintering molding” method for manufacturing copper-based friction materials (CFMs). The CFM-R4 (CFM with 4% RHC-SiO2) possesses a unique combination of high hardness (55.50 H V), low density (0.62 g/cm3), low wear rate (0.081%), suitable friction coefficient (0.26), and good durability. Based on the cost-effective method, the increased and decreased stages of RHC-SiO2 yield were determined mainly by reaction rate and compatibility, respectively. Compared with CFM-0 (CFM without SiO2), the CFM with RHC-SiO2 possesses better mechanical and friction properties. In view of high-performance and eco-friendly, such CFM with RHC-SiO2 would hold a promising application in friction fields such as transmission, differential, and synchronizer.

Despite considerable achievements in the use of porous carbon in electrochemical double-layer capacitor or electrode of supercapacitor over the past few years, understanding the relationship between pore structure parameters and electrochemical performance has long been highly desirable. Herein, apricot shell lignin (ASL) was used to prepare activated carbon, after which the galvanostatic charge–discharge (GCD) test was performed. Meanwhile, the pore structure parameters of AAC were determined by the nitrogen adsorption–desorption test. The results confirmed that the AAC pore structure parameters were consistent with the inherent law of activation. Besides, in the low current density ranging from 0.50 A/g to 10.00 A/g, the micropore surface area density of AAC rather than other pore structure parameters (e.g., mesoporosity, micropore specific surface area, mesopore specific surface area) was linearly positively related to its mass-specific capacitance. Additionally, the average of linear fit coefficients between micropore surface area density and mass-specific capacitance was 0.92. Consequently, when using a three-electrode configuration with a 6 M KOH electrolyte, the micropore surface area density of activated carbon can be employed as a universal predictor of mass-specific capacitance in a low current density range 0.50–10.00 A/g.

The main focus of this study was to give an idea for the value added from lignin and further understand the pore structure/electrochemical performance relationship. A case study of using H3PO4-assi...

To further understand the element migration characteristics and product properties during biomass pyrolysis, herein, pine cone (PC) cellulose and PC lignin were prepared, and their pyrolysis behavior was determined using thermogravimetric analysis (TGA). Subsequently, the PC was pyrolyzed in a vertical fixed bed reactor system at 400–700 °C for 60 min. The characteristics of element migration and the physicochemical properties of the pyrolysis products were analyzed and discussed. In the pyrolysis temperature range from 200 °C to 500 °C, there were two distinct weight loss peaks for PC. During the pyrolysis process, the C element was primarily retained in the biochar, while the O element mainly migrated into liquid and gaseous products in the form of compounds such as CO2, CO, and H2O. Besides, 28.42–76.01% of the N element in PC migrated into biochar. Of the three-phase products, the gases endow the lowest energy yield, while the energy of the biochar dominates the pyrolysis of the PC. Additionally, the N content and specific surface area for the PC-derived biochar obtained at 400 °C in a N2 atmosphere were higher than those of the biochar derived from fiberboard.

This work provides an idea for efficient and harmless utilization of lignin and further evaluated the textural properties of lignin-derived activated carbon/specific capacitance relationship. The yield of cellulose-doped apricot shell lignin (ASLC) was 30.42%. H3PO4/KOH was used to assist the preparation of ASLC-derived activated carbon (AAC) for capacitors. The specific surface areas of the as-obtained AAC-P-3 and AAC-K-2 were 1475.16 m2/g and 2136.56 m2/g, respectively. The specific capacitances of AAC-P-3 and AAC-K-2 were 169.14 F/g and 236.00 F/g, respectively, upon the current density of 0.50 A/g. In capacitors containing aqueous KOH as the electrolyte, the AR2 (0.983) between specific surface area and specific capacitance was highest, followed by the AR2 (0.978) between Vmicro/Vmeso and specific capacitance, the AR2 (0.975) between pore-wall thickness and specific capacitance. Consequently, the specific capacitances of the AACs depend not only the specific surface area, but also on the Vmicro/Vmeso, pore-wall thickness, and Vmicro.

BACKGROUND This study examined the combined effects of self-monitoring of blood glucose (SMBG) and educational attainment on glycemic control in type 2 diabetes mellitus (T2DM) patients. METHODS A cross-sectional survey was performed among community residents with T2DM. Good glycemic control was defined as HbA1c

Understanding the fuel properties of precursors/texture properties of precursor-derived porous carbons relationship has long been highly desirable. Here, different precursors were employed for synthesizing precursor-derived porous carbons using H3PO4 activation. Subsequently, the texture properties of precursor-derived porous carbons were revealed by N2 adsorption-desorption tests. Besides, the fuel properties of precursors were applied to correlate with the texture properties of their derived porous carbons. For fixed carbon, bamboo shaving (BS) being the highest, followed by olive shell (OS) and pine needle (PN). Notably, the high heating value (HHV) of BS was also the highest. The porous carbons prepared by the H3PO4 activation endow intensely developed meso/macropores. Compared with other fuel properties such as volatile, fixed carbon, and O/C, the HHV was more suitable as a general predictor of the porous carbon texture properties. The correlation yields an R2 value of 0.873 for the surface area density and HHV of the precursors. Consequently, in the present preparation conditions (the H3PO4 mass fraction, heating rate, activation temperature, and holding time were 58.10%, 10 °C/min, 550 °C, and 1 h, respectively), porous carbons with high surface area density can be predicted and target synthesis by selecting precursors with high HHV.

Background Smartphone use has become an increasingly pervasive part of our daily lives, and as a portable media device, smartphones provide good support for cognitive training during aging. However, little is known about the joint association of smartphone use and gender on the cognitive health of older adults, particularly with regard to multi-domain cognition. Methods A face-to-face survey of 3230 older adults aged 60+ years was conducted in Xiamen, China, in 2016. The Montreal Cognitive Assessment (MoCA) score was used to measure both general and multi-domain cognition. Smartphone use was self-reported and the number of the smartphone functions used (NSFU) was classified as 0, 1, and 2+. General and subdomain cognitive functions were modelled on NSFU only, gender only, and NSFU and gender combined by using a series of proportional-odds cumulative logit models. Furthermore, joint associations of gender and NSFU on both general and multi-domain cognition were estimated, and a four-category quantile classification was used to evaluate the total MoCA score. Results Among all 3230 respondents, 2600 remained after exclusion of respondents with very low MoCA scores (below the education-adjusted cut-offs for dementia). Only 29.96% of older adults used smartphones, 473 (60.72%) of which were men. Respondents who had a higher NSFU maintained a better general and sub-domain cognition except for memory and orientation. Although women had lower values compared to men in visuospatial ability (OR (95% CI): 0.46 (0.37–0.57)), they outperformed their male counterparts in memory (OR (95% CI): 1.38 (1.10–1.73)). The results of the joint association showed that women’s inferiority in visuospatial ability diminished when they had a NSFU of 2+. However, a significantly better improvement in memory for male was achieved when they had a NSFU of 1 rather than 2 + . Conclusions A higher NSFU was positively associated with increased general and partial subdomain cognitive functions. However, gender differences were found in visuospatial ability and memory, which could be alleviated by smartphone use.

Background The primary care reform developed in Xiamen City stood out among the dozens of pilot reforms conducted in China. The aim of this study was to investigate the effects of the reform. Methods The data were collected from the Annual Statistical Report on Xiamen's Hospitals and face-to-face questionnaire interviews among physicians (n = 107) and community members (n = 399). Binary logistic regression was performed to analyze the factors influencing the community members' preference for treatment in community health centers (CHCs). Results The drug cost declined nearly 3.0% in hospitals, and outpatient visits increased more quickly (27.1%) in CHCs. A total of 86.2% of community members preferred to receive treatment for slight illness or chronic diseases in CHCs, and 77.9% of them were willing to be referred to CHCs during the recovery period. Patients who were managed by the general practice (GP) team showed higher percentages in examining and controlling blood pressure and blood glucose. Conclusion The reform in Xiamen was easily accepted by physicians and community members. The reform had rendered initial achievements in reducing drug income in hospitals, increasing outpatient visits in CHCs, seeking health care in CHCs, and controlling blood pressure and glucose for patients with chronic diseases.

Sleep problems are very common in people with diabetes. The aim of this study was to assess the association of the combination of self-reported sleep duration and sleep quality on quality of life (QOL) in Chinese patients with type 2 diabetes mellitus (T2DM).We analyzed the community-based cross-sectional data of 798 patients with T2DM in Xiamen, China, in 2016. Sleep duration was measured as self-reported average sleep time during the previous month. Sleep quality was evaluated as self-rated reports. QOL was assessed by the Diabetes-specific Quality of Life (DSQL), with scores 40 and ≥ 80 set as cut-off values for differentiating good, fair, and poor QOL. Ordinal logistic regression was performed to model the associations of QOL with sleep duration, sleep quality, and their combined effects by adjusting for certain covariates.The separate associations of sleep duration and sleep quality in relation to QOL in T2DM patients were significant (P 0.05). After controlling for sleep quality, there was no significant correlation between sleep duration and QOL. The combined analysis suggested that the association of sleep duration with QOL in T2DM patients was sleep quality-dependent. Longer sleep duration was associated with higher odds ratios (ORs) of better QOL for patients who reported fair sleep quality and good sleep quality, but no such trend was observed for patients who reported poor sleep quality (P0.05). Excessive sleep duration (≥ 9 h per day) was detrimental to QOL in T2DM only when they reported poor sleep quality.Specific disparities exist in the association of sleep quality with sleep duration and QOL in T2DM patients. Failures to take into account the effect of sleep quality when evaluating the impact of sleep on QOL significantly bias the results. It is important to integrate duration and quality of sleep as a composite sleep index when assessing sleep of patients with T2DM.

This study examined the combined effects of self-monitoring of blood glucose (SMBG) and educational attainment on glycemic control in type 2 diabetes mellitus (T2DM) patients.A cross-sectional survey was performed among community residents with T2DM. Good glycemic control was defined as HbA1c7% in the most recent measurement. Multivariable logistic regression was used to examine associations of glycemic control with SMBG, educational attainment, and their combined effects by controlling for certain covariates, with further stratification by sex.Complete data were available for 798 patients, of which 58.52% had good glycemic control. Higher education and SMBG were associated with good glycemic control (P 0.05). In the SMBG group, tertiary-educated patients had the greatest odds of good glycemic control (odds ratios 2.56; 95% confidence interval 1.31-4.99). Among those performing SMBG, the odds of good glycemic control were higher for those with higher education levels (PSex-specific educational disparities exist in the association between SMBG and glycemic control. More detailed guidelines for SMBG according to a subject's socioeconomic position and sex are required.

This paper presents a many-objective reactive power optimization model which consists of minimum active power loss, minimum node voltage deviation, maximum static voltage stability and maximum power supply capability. To efficiently solve this model, a novel approach by using particle swarm optimization is proposed. This approach is called many-objective particle swarm optimization algorithm based on Pareto entropy which adopts loose Pareto dominant relationship and maps the Pareto front from cartesian coordinate system to parallel cell coordinate system, thus designing evolutionary strategies using Pareto front's distribution entropy and entropy difference in the new coordinate system. The presented algorithm is capable to balance convergence and diversity of the approximate Pareto front. Moreover, cell dominant intensity and individual density are introduced to assess the individual environment fitness of the Pareto optimal solution, and we hereby design the selection strategy of the global best solution. Simulations based on the IEEE 14-bus systems demonstrate the effectiveness of the proposed model and the efficiency of the proposed algorithm.

The observation of corona discharge points on the surfaces of the insulating materials and conductors seem to be quite crucial during the corona researches. The ‘solar blind’ ultraviolet imaging detector cameras have performed efficiently in detecting corona discharge in power facilities. In order to investigate the negative dc corona effects on ultraviolet photon count, a corona measurement system based on rod to plane air gaps was established. The corona current, Trichel pulses and corona- generated photons were measured with the raise of applied voltage. An approximate parabolic function was found to exist between the photon count and the corona current. And also an ideal quadratic function was discovered to exist between the photon count and the frequency of Trichel pulses. These results have provided solid foundation in the application of UV imaging detection of negative dc corona in power equipments.

The electric properties of nanocomposites are determined by the interface between nano particles and epoxy resin, so the interface modification is very important. In this paper, silane coupling agent which has a carbon-carbon double bond and an oxymethylphenyl was used to modify the surface of α-Al 2 O 3 . In the modification, carbon-carbon double bonds were introduced to the surface of nano particles. The carbon-carbon double bonds will serve as active groups in the grafting process. The polyacrylamide (PAAM) was grafted on the surface of α-Al 2 O 3 . And the amino groups were introduced to the surface of α-Al 2 O 3 . Then the interface between the nano particle and the epoxy resin can be reinforced by the reaction between the amino group and epoxy ring. The FTIR (Fourier Transform Infrared) spectrum of grafted alumina was tested to confirm the modification and grafting process. Then, five kinds of materials were prepared, i.e. neat epoxy, micro composites, and three kinds of nanocomposites with different contents of PAAM grafted alumina particles. The specimens with thickness of 200 µm were prepared for investigation. The SEM micrographs were investigated to observe the dispersion of nano particles in epoxy resin. And the properties including the thermal behavior, dielectric strength, and dielectric spectrum were measured and analyzed. It is concluded that the epoxy nanocomposites loaded with PAAM grafted alumina particles show homogeneous dispersion, increasing thermal degradation initiation temperature and higher dielectric breakdown strength.

With the aim of reducing the insulation faults in GIS and achieving the purpose of GIS device miniaturization, it is very important to develop a new type insulation material. In this paper, the micro-nano Al 2 O 3 /Epoxy composites were proposed, and its dielectric breakdown strength was investigated. Nano-fillers and micro-fillers (α-Al 2 O 3 with a purity of 99.9%, particle size range at 12~21 μm for micro fillers, and average particle size with 30 nm for nano fillers) were dispersed in the epoxy resin with shear force and ultrasonic vibration. The specimens were produced by a curing reaction with the hardener. Six kinds of material were prepared for this investigation, which were neat epoxy, nano-composite (loaded with 5 wt% nano-Al 2 O 3 fillers), nano-composite (loaded with 5 wt% nano-TiO 2 fillers),micro-composite (loaded with 65 wt% micro-Al 2 O 3 fillers), nano-micro-mixture-composites (loaded with 2 wt% nano-Al 2 O 3 fillers and 63 wt% micro-Al 2 O 3 fillers), nano-micro-mixture-composites (loaded with 2 wt% nano-TiO 2 fillers and 63 wt% micro-Al 2 O 3 fillers). Dispersion of the micro and nano Al 2 O 3 in the epoxy resin was observed through SEM, and thermal behavior was analyzed with Thermo-Gravimetric Analysis (TGA) and differential scanning calorimeter (DSC). The dielectric constant and dielectric loss were measured by broadband dielectric spectrum test facility. Dielectric breakdown experiments were carried out through the sphere-plate sample-sphere configuration under AC voltage.