The resource utilization of waste is of great significance to the sustainable development of society. Waste cooking oil (WCO) and reclaimed asphalt pavement (RAP), two typical wastes, have been ...plaguing the ecological environment for a long time. In this work, the different components of WCO were separated and employed separately as recycling agents for RAP to determine the suitability of various substances in WCO with RAP. The effects of different components of WCO on the rheological properties of aged asphalt were determined through dynamic shear rheometer (DSR) and bending beam rheometer (BBR). Meanwhile, the microscopic characteristics of rejuvenated asphalt using different WCO components were also discussed by atomic force microscope (AFM), Fourier transform infrared spectroscopy (FT-IR), and cluster analysis (CA). The experimental results indicate that all components of WCO have a significant effect on mitigating the brittleness of aged asphalt. However, some wax-like substances such as methyl palmitate in WCO are prone to solid-liquid phase transformation when the temperature decreases, which has a poor recovery effect on the fatigue and low-temperature performance of aged asphalt. It is suggested that waxy substances in WCO should be eliminated in advance to achieve efficient and stable regeneration of RAP when WCO is recycled as recycling agents for RAP. In terms of micro perspective, it is found that the lower the molecular weight of the WCO component is, the better its restoration effect on microscopic characteristics of aged asphalt is. The different effects of various substances in WCO on aged asphalt can be observed more intuitively after the classification of WCO components, which is instructive for the engineering application of efficient recovery of RAP using WCO.
Accumulating evidence suggest that long noncoding RNAs (lncRNAs) are dysregulated in various tumors and serve as crucial regulators in biological processes. Based on The Cancer Genome Atlas (TCGA) ...database, upregulation of CASC11 was associated with the low overall survival rate of patients with Hepatocellular carcinoma (HCC). However, the function and mechanism of lncRNA CASC11 in the progression of HCC remain unclear. Therefore, we further analyzed the expression pattern and biological role of CASC11 in HCC. CASC11 was found to be overexpressed in HCC tissues and cell lines and predicted a poor prognosis. Loss of CASC11 function efficiently suppressed cell migration, invasion and epithelial-mesenchymal transition (EMT). The mechanism which led to the upregulation of CASC11 was investigated. CASC11 was found to be activated by the transcription factor STAT3. Mechanically, the enhancer of zeste homolog 2 (EZH2) was found to be a binding partner of CASC11. Moreover, CASC11 epigenetically silenced PTEN by binding with EZH2. Finally, rescue assays were conducted to make confirmation. The present results revealed that CASC11 may be potential therapeutic target in HCC.
•LncRNA CASC11 played oncogenic role in HCC.•CASC11 was activated by the transcription activator STAT3.•CASC11 epigenetically silenced PTEN by interacting with EZH2.•LncRNA CASC11 activated PI3K/AKT signaling pathway.
This study investigated the influence of Coronavirus Disease 2019 (COVID-19) on lung function in early convalescence phase.
A retrospective study of COVID-19 patients at the Fifth Affiliated Hospital ...of Sun Yat-sen University were conducted, with serial assessments including lung volumes (TLC), spirometry (FVC, FEV1), lung diffusing capacity for carbon monoxide (DLCO),respiratory muscle strength, 6-min walking distance (6MWD) and high resolution CT being collected at 30 days after discharged.
Fifty-seven patients completed the serial assessments. There were 40 non-severe cases and 17 severe cases. Thirty-one patients (54.3%) had abnormal CT findings. Abnormalities were detected in the pulmonary function tests in 43 (75.4%) of the patients. Six (10.5%), 5(8.7%), 25(43.8%) 7(12.3%), and 30 (52.6%) patients had FVC, FEV1, FEV1/FVC ratio, TLC, and DLCO values less than 80% of predicted values, respectively. 28 (49.1%) and 13 (22.8%) patients had PImax and PEmax values less than 80% of the corresponding predicted values. Compared with non-severe cases, severe patients showed higher incidence of DLCO impairment (75.6%vs42.5%, p = 0.019), higher lung total severity score (TSS) and R20, and significantly lower percentage of predicted TLC and 6MWD. No significant correlation between TSS and pulmonary function parameters was found during follow-up visit.
Impaired diffusing-capacity, lower respiratory muscle strength, and lung imaging abnormalities were detected in more than half of the COVID-19 patients in early convalescence phase. Compared with non-severe cases, severe patients had a higher incidence of DLCO impairment and encountered more TLC decrease and 6MWD decline.
To investigate the prevalence and influencing factors of Demodex folliculorum (DF) in the eyelashes of healthy young males. An epidemiological cross-sectional prevalence study was conducted. We ...conducted visual acuity, eye-related examination, eyelash microscopic examination and DF count of recruits in Fujian Province in 2019. The presence of DF was analyzed according to age, keratorefractive surgery, annual household income, educational level, long-term residence, sleep time, time of using electronic products, smoking and drinking habit. A total of 2253 healthy young males (aged 17-24 years) were studied for the presence of DF within eyelash follicles. The total prevalence of DF was 20.73% in our study. Subjects with history of keratorefractive surgery had a statistically significant increase in the prevalence of DF (P < 0.001). The prevalence of DF was higher in subjects with ocular symptoms than in those without symptoms (P < 0.05). Factors such as the educational level and so on we analyzed had no significant correlation with the prevalence of DF (all P > 0.05). According to the multivariate logistic regression analysis, the history of keratorefractive surgery was the risk factors of DF infection (P < 0.001), and the risk of infection was 1.437 times higher in the population with the history of keratorefractive surgery than in the population without. There was no correlation between ocular discomfort and DF infection (P > 0.05). The prevalence of DF in eyelash follicles in healthy young males was relatively high. The history of keratorefractive surgery was an important risk factor for the infection.
•An innovative grading method for waste cooking oil and redefining waste cooking oil components by molecular weight;•The molecular properties, thermal stability and compatibility with asphalt of ...different components of waste cooking oil were studied in comparison;•For the above properties, macromolecular substances in waste cooking oil were selected as regenerants while its influence on the physical, rheological and chemical properties of asphalt with different aging degrees were investigated.;•The sensitivity of the properties of rejuvenated asphalt to the dosage of macromolecules in waste cooking oil is inversely related to the degree of asphalt aging.
Waste cooking oil (WCO) is generally regarded as one of components for the rejuvenators in recycled asphalt pavement (RAP). However, WCO has many kinds of substances and unstable characteristics due to its different sources, causing differences to the properties of rejuvenated asphalt. In this research, an innovative method of classification was adopted to transform WCO into small, middle and macromolecular substances according to the molecular weight. The thermogravimetric analysis revealed that macromolecular substances (Wmas) in WCO has better thermal stability. Combined with the results of separation test, Wmas has better compatibility with asphalt. Subsequently, the study of the physical, rheological and chemical properties was conducted for asphalt with three different aging degrees after regeneration by Wmas. The experimental results show that the adequate distribution of Wmas in the asphalt makes the aging asphalt soften effectively. Moreover, the rejuvenated asphalt exhibits superior high and low temperature rheological properties. However, the physical and rheological properties of the three aged asphalts differ in the rapidity of recovery and the dosage of Wmas. Meanwhile, the excessive dosing of Wmas will cause negative effects, such as a sharp decrease in viscosity and slow change in ductility of the asphalt. In addition, functional groups of rejuvenated asphalt show that Wmas does not react chemically with asphalt. The regeneration of aged asphalt by Wmas depends on its physical compatibility with asphalt and thermal stability. Overall, the properties of the aged asphalt can be restored to the level of virgin asphalt at the appropriate dosing of Wmas, but the sensitivity to the dosage of Wmas varies. The above study provides ideas for targeted restoring mechanisms between waste cooking oil components and aged asphalt.
Different proportions of bio-oil (5, 10, 15, and 20 wt%) were added into aged asphalt for its regeneration. Molecular dynamic simulations were used to measure the thermal and mechanical performances ...of bio-oil regenerated aged asphalt (BRAA). A new, simplified BRAA model was built to calculate the specific heat capacity, thermal expansion coefficient, elastic constant, shear modulus, bulk modulus, and Young's modulus. Simulation results showed that the thermal expansion coefficient (CTE α) of asphalt at 298 K decreased by 10% after aging. Bio-oil of 5 wt% could make the CTE α restore to the original level of base asphalt, while the addition of bio-oil would further decrease the specific heat capacity of aged asphalt. The shear modulus (G), Young's modulus (K) and bulk modulus (E) of asphalt increased after aging and decreased with the increasing amount of bio-oil. According to the calculated E/G value, the ductility of aged asphalt increased by 6.0% with the addition of 10 wt% bio-oil, while over 15 wt% bio-oil would make the ductility of BRAA decrease. In summary, the regeneration effects of bio-oil to the thermal expansion coefficient, flexibility, and ductility of aged asphalt had been proven, while excessive bio-oil would decrease the thermal stability of asphalt.
Using phase change materials (PCMs) in building envelopes became a reliable method to improve indoor comfort and reduce buildings' energy consumption. This research developed molecular-bridged ...expanded graphite (EG)/polyethylene glycol (PEG) composite PCMs (m-EPs) to conserve energy in buildings. The m-EPs were prepared through a vacuum absorption technique, and a titanate coupling agent was used to build a molecular bridge between EG and PEG. SEM, mercury intrusion porosimetry (MIP), the leakage test, microcalorimetry, X-ray photoelectron spectroscopy (XPS), and Fourier transform infrared spectroscopy (FT-IR) were conducted to characterize the morphology, pore structure, absorbability, and modifying effects of the m-EPs. The phase change temperature, latent heat, thermal stability, and thermal conductivity of the m-EPs were determined by a differential scanning calorimeter (DSC), TGA, and a thermal constants analyzer. Results showed that the maximum mass ratio of PEG to EG without leakage was 1:7, and a stable connection was established in the m-EPs after modification. Compared with the unmodified EPs, the supercooling degree of the m-EPs reduced by about 3 °C, but the latent heats and initial decomposition temperatures increased by approximately 10% and 20 °C, respectively, which indicated an improvement in the thermal energy storage efficiency. The thermal conductivities of the m-EPs were 10 times higher than those of the pristine PEGs, which ensured a rapid responding to building temperature fluctuations.
•It was found that a novel type of microencapsulated phase change material (methyl palmitate derived from waste cooking oil), and the phase transition temperature was suitable for application in the ...field of building energy conservation.•Using methyltriethoxysilane as the wall material, microcapsules with methyl palmitate as the core material were obtained by suspension polymerization and high-speed centrifugal precipitation. The coating rate was 48.97 % and the physical and chemical properties were stable.•It was found that the structure created by directly incorporating the microcapsules as additives into foam concrete can be used in construction, as it increases its strength and significantly mitigates the impact of ambient temperature on buildings.
The utilization of waste resources and the intelligence of building materials are of great significance to the sustainable development of human society. A novel type of microencapsulated phase change material (MPCM) with a phase change heat storage capability was prepared in this paper through the suspension polymerization method using methyl palmitate (MP) derived from waste cooking oil as core materials. Meanwhile, the response of foamed concrete containing MPCM to ambient temperature change was investigated. According to the experimental findings, the MPCM's phase change temperature, phase change enthalpy, and decomposition temperature are respectively 20 °C, 68 J/g, and 215 °C, which is extremely suitable for the external walls of buildings to adjust the indoor temperature. Moreover, the particle size of the MPCM is about 100 μm-220 μm, which can fill part of the voids in foam concrete to increase its strength. Additionally, the infrared thermal imaging experiment indicates that the foam concrete containing 10 wt% MPCM can maintain 4 °C-5 °C gap with the ambient temperature, which demonstrates that the MPCM can significantly mitigate the impact of ambient temperature on buildings. The findings of the study contribute to the intellectualization of building materials and the recycling of waste resources.
•A gradation carbonation method for recycled cement concrete (RCC) is proposed.•The carbonation effect of RCC with different particle sizes is investigated.•The effect of carbonized aggregates and ...powder on the physical and chemical properties of artificial stone are studied.
The utilization of recycled cement concrete (RCC) will be helpful to achieve the goal of carbon peak and carbon neutrality, especially the treatment of RCC by carbonation, which will improve the RCC’s properties. In this article, RCC was crushed and sieved into 6 grades of aggregate and powder according to the particle size. Each size of aggregate and powder was carbonized separately by CO2. The apparent relative density, specific surface area and cementitious activity were tested before and after the carbon sequestration. The effect of these materials, which included graded substituting cement and quartz sand, were investigated on the strength of artificial stone. The experimental results indicate that the carbon sequestration efficiency increases gradually with the decrease of particle size of RCC. The physical properties of the aggregates are better after carbon sequestration. In terms of apparent relative density, the maximum increasing rate is 2.59 %, and simultaneously the water absorption is reduced by at least 2.18 %. The preparation parameters of artificial stone are that the constant pressure time is 30 s and the forming pressure is 30 MPa. The increase in the content of recycled aggregate and powder will lead to a decrease in the compressive strength of artificial stone, but compared with the recycled material before carbonation, the compressive strength of artificial stone with the same content is significantly improved, with a maximum increase of 36.53 %. Moreover, the nano-indentation depth of artificial stone decreases using carbonation RCC, which indicates that the interface strength of cement pastes and carbonized aggregates is improved. This research demonstrates that the physical properties and interfacial strength of RCC through gradation carbonation are improved, which provides a valuable method for the graded utilization of RCC and the sustainable development of artificial stone.
PDF
