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1.
Biomed Pharmacother ; 121: 109560, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31739160

RESUMO

Radiation-induced fibrosis (RIF) is a severe long-term complication of the normal tissue following radiotherapy. Its prototypical characteristic is the persistent activation of myofibroblasts, resulting in proportion disorder and hyperplasia remodeling of the extracellular matrix comprising collagen. The continuous progress of RIF may contribute to multiple clinical manifestations such as hollow organ stenosis, impaired gaseous diffusion, and loss of tissue compliance significantly affecting the overall quality of daily life in patients with irradiated cancer. Traditionally, the potential mechanism of myofibroblast activation and differentiation has not been elucidated, and the process has been considered as static and irreversible. Recent studies have shown that RIF is a dynamic, multi-step process mediated by many regulated chemokines and cytokines. The RIF process includes release of reactive oxygen species (ROS), microvascular injury, recruitment of inflammatory cells, and activation of myofibroblasts. Numerous signaling pathways are involved in the initiation and progression of RIF, of which SMAD-regulated CTGF expression mediated by TGF-ß1 is referred as the main axis. Current management strategies applied in clinical practice for patients with RIF are only supportive treatments, such as anti-inflammatory therapy using steroids; however, the efficacies achieved by these interventions are limited and unsatisfactory. Therefore, this review explores advances in RIF pathogenesis and anti-fibrosis therapy. We hope to provide clinicians with improved awareness and enormous promise in the management of RIF.

2.
Biomed Chromatogr ; : e4767, 2019 Nov 30.
Artigo em Inglês | MEDLINE | ID: mdl-31785600

RESUMO

Disorders of certain branched-chain amino acids (BCAAs) may be associated with the occurrence and development of non-alcoholic fatty liver disease (NAFLD). Measurement of related BCAAs levels could provide a reference for the clinical and scientific research of the NAFLD. An established HPLC-FLD method was used to quantify Aspartic acid (Asp), Glutamate (Glu), Glutamine (Gln), Glycine (Gly), Taurine (Tau), Tyrosine (Tyr), 4-Amino butanoic acid (GABA), Tryptophan (Trp), Methionine (Met), Valine (Val), Phenylalanine (Phe), Isoleucine (Ile), and Leucine (Leu) in mice brain tissue. Brain tissue samples mixed with internal standard (DL-3-Aminobutyric acid) were processed, then derivatized with 2-O-phthaldialdehyde (OPA), and finally separated on an ODS2 column through gradient elution at a flow rate of 1.0 mL·min-1 . The excitation and emission wavelengths were set at 340 nm and 455 nm respectively. The mobile phase A was 100% methanol and the mobile phase B consisted of 30 mmol·L-1 sodium acetate (pH 6.8). The injection volume was 20 µL and the single run time was 45 min. Several parameters, accuracy, precision, and stability, were verified and the results showed the established method had good sensitivity and resolution for all of the 13 compounds and internal standard (IS) in mice brain.

3.
Environ Res ; 179(Pt B): 108838, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31678730

RESUMO

Polycyclic aromatic hydrocarbons (PAHs) and phthalic acid esters (PAEs) which are structurally featured with one or more aromatic skeletons are often regarded as two important groups of organic pollutants due to the widespread distribution and notorious toxic effects in soils. Relative to the great number of structural analogues or congeners detected in soil, however, the soil adsorption and bioaccumulation of PAHs/PAEs by plant is far less studied for the insufficiency of experimental determinations or lack of insights into the inherent structural requirements. To mechanistically evaluate the congener-specific soil adsorption and bioaccumulation for PAHs/PAEs, the quantitative structure-activity relationships (QSARs) were successfully developed by density functional theory (DFT) computation and partial least squares (PLS) analysis. As verified with the higher cumulative variance coefficients and cross-validated correlation coefficients for strong stability, interpretability and predictability, the QSARs could be used for prediction of unknown adsorption potency or bioavailability within the specified applicability domain, respectively. It was indicated by QSAR that the structural requirements of PAHs/PAEs necessary for strengthening the soil adsorption were mainly attributed to the molecular polarizability and the associated dispersion interaction with soil. As regards the bioaccumulation by carrot, the aggravation of spherical polarity change of molecules and the involved electrostatic interaction with soil entity or electron transfer from the highest occupied molecular orbital (HOMO) of PAHs/PAEs was implied to be inherently decisive for the variance of bioavailability among congeners. Based on the holistic view of negative correlation relationship, the soil adsorption seemed to act as the forceful constraint in decreasing the bioaccumulation of PAHs/PAEs and could also be alternatively gauged as the preliminary evaluation of bioavailability and risks on soil ecosystem. It would thus help better understand the soil adsorption and bioaccumulation with the informative mechanistic insights and provide data support for ecological risk assessment of PAHs/PAEs in soils.

4.
Sci Total Environ ; 702: 134956, 2019 Nov 03.
Artigo em Inglês | MEDLINE | ID: mdl-31710852

RESUMO

Herein, a surface-enhanced Raman scattering (SERS) strategy based on semiconducting substrate was exploited for detection of several antibiotic residues both in ultrapure water system and in actual water system. The as-prepared Ag-TiO2 (Ag synchronously deposited and doped TiO2) nanoparticle SERS-active substrate can achieve high sensitive SERS detection for difloxacin hydrochloride, ciprofloxacin, enrofloxacin, danofloxacin and enoxacin (five widely used quinolone antibiotics) in actual water samples, and the detection limits are as low as 4.36 × 10-12, 7.08 × 10-11, 3.94 × 10-11, 3.16 × 10-11 and 3.15 × 10-10 mol/L, respectively. These detection limits are far below the maximum of residue limit (3.01 × 10-7 mol/L) stipulated by the European Union. And, the desirable quantitative relationships can be obtained in a wide concentration range. The recoveries of five antibiotic residues from spiked actual water samples are found to be more than 80.8% with the relative standard deviations between 2.1% and 4.7%. Even, the proposed SERS method can accurately distinguish every antibiotic species from a mixed antibiotic residue sample with multiple antibiotics. And, Ag-TiO2 nanoparticles can also serve as an efficient photocatalyst for photocatalytic degradation of these antibiotic residues, which provides a multi-functional platform for synchronous determination and degradation of antibiotic residues in real environment.

5.
Oxid Med Cell Longev ; 2019: 3010342, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31781332

RESUMO

Radiotherapy (RT) is currently one of the leading treatments for various cancers; however, it may cause damage to healthy tissue, with both short-term and long-term side effects. Severe radiation-induced normal tissue damage (RINTD) frequently has a significant influence on the progress of RT and the survival and prognosis of patients. The redox system has been shown to play an important role in the early and late effects of RINTD. Reactive oxygen species (ROS) and reactive nitrogen species (RNS) are the main sources of RINTD. The free radicals produced by irradiation can upregulate several enzymes including nicotinamide adenine dinucleotide phosphate oxidase (NADPH oxidase), lipoxygenases (LOXs), nitric oxide synthase (NOS), and cyclooxygenases (COXs). These enzymes are expressed in distinct ways in various cells, tissues, and organs and participate in the RINTD process through different regulatory mechanisms. In recent years, several studies have demonstrated that epigenetic modulators play an important role in the RINTD process. Epigenetic modifications primarily contain noncoding RNA regulation, histone modifications, and DNA methylation. In this article, we will review the role of oxidative stress and epigenetic mechanisms in radiation damage, and explore possible prophylactic and therapeutic strategies for RINTD.

6.
Cancer Med ; 2019 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-31733044

RESUMO

OBJECTIVE: To evaluate the association of human papilloma virus (HPV) infection with prognosis, specifically overall survival (OS) and disease-free survival (DFS), in laryngeal squamous cell carcinoma (LSCC) patients. METHOD: A systematic review and meta-analysis were performed according to the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines. LSCC was confirmed on the basis of histopathology, whereas HPV status was confirmed by polymerase chain reaction. RESULTS: A total of 6539 articles were initially searched from 8 databases, of which 11 studies were eligible for our review. A total of 1442 LSCC cases were included in this analysis. Eight studies examined 3-year OS for LSCC. The pooled hazard ratio (HR) from the 8 studies was 0.29 (95% CI: 0.25-0.33). There was a statistically significant difference in 3-year OS between the HPV-negative and -positive groups, with the latter having a better survival. There was no statistically significant differences in 5- and 10-year OS. Five studies examined 3- and 5-year DFS for LSCC, whereas only 3 studies examined 10-year DFS. There was no statistically significant difference in 3-, 5-, and 10-year DFS between the HPV groups. CONCLUSION: This study evaluated the survival impact of HPV infection in LSCC patients. The OS of the HPV-positive group was better than that of the HPV-negative group in terms of short-term survival. Compared with the HPV-negative group, the HPV-positive group had a better trend of DFS, suggesting that a larger sample size and further exploration of the pathology and local control of HPV-positive tumors are needed.

7.
Cell Death Differ ; 2019 Nov 19.
Artigo em Inglês | MEDLINE | ID: mdl-31745213

RESUMO

The removal of superfluous and unwanted cells is a critical part of animal development. In insects the steroid hormone ecdysone, the focus of this review, is an essential regulator of developmental transitions, including molting and metamorphosis. Like other steroid hormones, ecdysone works via nuclear hormone receptors to direct spatial and temporal regulation of gene transcription including genes required for cell death. During insect metamorphosis, pulses of ecdysone orchestrate the deletion of obsolete larval tissues, including the larval salivary glands and the midgut. In this review we discuss the molecular machinery and mechanisms of ecdysone-dependent cell and tissue removal, with a focus on studies in Drosophila and Lepidopteran insects.

8.
Artigo em Inglês | MEDLINE | ID: mdl-31746033

RESUMO

In this study, nutrient loss, the direct and indirect relationship between period, compost types, temperature, total nitrogen (TN), nitrate nitrogen (NO3 - -N), ammonia nitrogen (NH4 + -N), microbial biomass carbon (MBC) and nitrogen (MBN) were investigated during composting of cattle manure-maize straw mixture. This study findings revealed that biochar addition lowered NH4 + -N but did not increase NO3 - -N concentrations unlike no biochar piles during composting. The first-order kinetic models showed that biochar accelerated organic matter (OM) degradation, improved N mineralization, consequently reducing TN losses by 13.6% and OM losses by 12.66%. Transformation ratio of MBC/MBN, coupled with other chemical components of the entire microbial community suggested a shift in the microbial succession and diversity during composting from the dominant bacteria and actinomycetes to fungi. The Structural equation model and path coefficient revealed temperature to be the main factor mediating the evolution of MBC and MBN in composting. The physicochemical variables, phytotoxicity and final product quality revealed that biochar incorporation to the composting feedstock is an ideal material for mitigating problems of TN and OM losses in composting and ultimately enhancing the fertility potential of the final compost product. This article is protected by copyright. All rights reserved.

9.
Artigo em Inglês | MEDLINE | ID: mdl-31748779

RESUMO

Schwann cells are the main force in spontaneous regeneration after peripheral nerve injury. The neurotrophic factors could promote the regeneration, but clinical applications of these factors are limited by some constraints. Hence, searching for new substances to elevate the function of Schwann cells and facilitate the regeneration of nerve is urgently needed. Syringic acid (SA) is a natural product with neuroprotective activity in vivo, but the role of SA on Schwann cells remains unclear. In this study, we for the first time found that SA was able to promote the proliferation and migration of Schwann cells, two important abilities in the process of regeneration. Then, microRNA (miRNA) microarray analysis was performed and 26 differentially expressed miRNAs (22 down-regulated and 4 up-regulated) were identified. Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) signaling pathway analyses found that the target genes of these miRNAs were mainly enriched in cellular response to chemical stimulus and cancer-related pathways, respectively. Subsequently, the levels of top 6 down-regulated miRNAs were validated by RT-qPCR and miR-451-5p was shown to be the most down-regulated one. Further experiments demonstrated that inhibition of miR-451-5p significantly promoted the proliferation and migration of Schwann cells. These results suggested that SA promoted the proliferation and migration of Schwann cells via down-regulation of miR-451-5p, and SA could be developed into a promising nutritional supplement to assist peripheral nerve regeneration.

10.
Nat Commun ; 10(1): 5083, 2019 Nov 08.
Artigo em Inglês | MEDLINE | ID: mdl-31704937

RESUMO

Nanoscale transport through nanopores and live-cell membranes plays a vital role in both key biological processes as well as biosensing and DNA sequencing. Active translocation of DNA through these nanopores usually needs enzyme assistance. Here we present a nanopore derived from truncated helicase E1 of bovine papillomavirus (BPV) with a lumen diameter of c.a. 1.3 nm. Cryogenic electron microscopy (cryo-EM) imaging and single channel recording confirm its insertion into planar lipid bilayer (BLM). The helicase nanopore in BLM allows the passive single-stranded DNA (ssDNA) transport and retains the helicase activity in vitro. Furthermore, we incorporate this helicase nanopore into the live cell membrane of HEK293T cells, and monitor the ssDNA delivery into the cell real-time at single molecule level. This type of nanopore is expected to provide an interesting tool to study the biophysics of biomotors in vitro, with potential applications in biosensing, drug delivery and real-time single cell analysis.

11.
Artigo em Inglês | MEDLINE | ID: mdl-31718139

RESUMO

Large volume expansion and serious pulverization of silicon are two major challenges for Si-based anode batteries. Herein, a high-mass-load (3.0 g cm-3) silicon-doped amorphous carbon (Si/a-C) nanocomposite with a hierarchical buffer structure is prepared by one-step magnetron sputtering. The uniform mixing of silicon and carbon is realized on the several-nanometer scale by cosputter deposition of silicon and carbon. The boundary of the primary particles, made up of nanocarbon and nanosilicon, and the boundary of the secondary particles aggregated by the primary particles can provide accommodation space for the volume expansion of silicon and effectively buffer the volume expansion of silicon. Meanwhile, the continuous and uniformly distributed amorphous carbon enhances the conductivity of the Si/a-C nanocomposites. Typically, the 20% Si/a-C cell shows a superior initial discharge capacity of 845.3 mAh g-1 and achieves excellent cycle performance of up to 1000 cycles (609.4 mAh g-1) at the current density of 1 A g-1. Furthermore, the 20% Si/a-C cell exhibits a high capacity of 602.8 mAh g-1 with the stable discharge/charge rate performance in several extreme conditions (-40-70 °C). In view of the validity and mass productivity of the magnetron sputtering, a potential route for the industrial preparation of the Si/a-C anode nanocomposites is therefore highlighted by this study.

12.
Braz J Med Biol Res ; 52(11): e8371, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31721903

RESUMO

Oxiracetam (ORC) is a commonly used nootropic drug for improving cognition and memory impairments. The therapeutic effect and underlying mechanism of ORC in vascular dementia (VaD) treatment remain unknown. In this study, 3-month-old male Sprague-Dawley rats with permanent bilateral common carotid artery occlusion-induced VaD were treated orally with low (100 mg/kg) or high (200 mg/kg) dose ORC once a day for 4 weeks. The results of the Morris water maze test and Nissl staining showed that ORC treatment significantly alleviated learning and memory deficits and neuronal damage in rats with VaD. Mechanistically, the protein levels of a panel of genes associated with neuronal apoptosis (Bcl-2, Bax) and autophagy (microtubule-associated protein 1 chain 3, Beclin1, p62) were significantly altered by ORC treatment compared with VaD, suggesting a protective role of ORC against VaD-induced neuronal apoptosis and autophagy. Moreover, the Akt/mTOR pathway, which is known to be the upstream signaling governing apoptosis and autophagy, was found to be activated in ORC-treated rats, suggesting an involvement of Akt/mTOR activation in ORC-rendered protection in VaD rats. Taken together, this study demonstrated that ORC may alleviate learning and memory impairments and neuronal damage in VaD rats by altering the expression of apoptosis/autophagy-related genes and activation of the Akt/mTOR signaling pathway in neurons.

13.
Clin Transl Gastroenterol ; 10(10): e00074, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31609743

RESUMO

OBJECTIVE: Increasing evidence has indicated an association between gut microbiota in gastrointestinal cancer and clinical outcome. Herein, we aim to develop a prognosis-prediction tool based on an immune-lipid metabolism signature, tumor cell-associated immune microenvironment, and lipid metabolism proteins inferred from the function of gut microbiota. METHODS: 16S gene ribosomal RNA sequencing was performed on 10 fecal samples obtained after tumor resection but before chemotherapy (EBVaGC = 4 and EBVnGC = 6). Least absolute shrinkage and selection operator (LASSO) Cox regression was applied to screening for highly accurate marker proteins. A compound score based on the fraction of screened markers was then constructed using a LASSO logistic regression model. RESULTS: The Tax4Fun analysis based on Kyoto Encyclopedia of Genes and Genomes data indicated differentially expressed tumor pathway between EBVnGC and EBVaGC. Using the LASSO logistic model, a compound score was established consisting of 14 types of immune microenvironment and lipid metabolism proteins. In the training set (378 patients), significant differences were found between high- and low-compound score groups in overall survival across and within subpopulations with an identical EBV. Multivariable analysis revealed that the compound score was an independent prognostic factor (hazard ratio, 2.26; 95% confidence interval = 2.28-3.36). The prognostic value ;of the compound score was also confirmed in the validation (162 patients) and entire (540 patients) sets. DISCUSSION: The proposed compound score is a promising signature for estimating overall survival in patients with gastric cancer having EBVaGCs or EBVnGCs.

14.
Anat Rec (Hoboken) ; 2019 Oct 08.
Artigo em Inglês | MEDLINE | ID: mdl-31595632

RESUMO

The CCAAT-enhancer-binding protein α (C/EBPα) plays an important role in adipogenic differentiation of adipose-derived stem cells (ASC). Recent studies have shown that microRNAs (miRNAs) participate in the regulation of self-renewal, proliferation, and multi-directional differentiation of ASCs. In the present study, we analyzed the targeting miRNAs on C/EBPα and found that miR-326 played an essential role in it. The results of qPCR confirmed that the expression of miR-326 was reduced in adipogenic differentiation. In addition, the dual-luciferase reporter assay system verified binding between miR-326 and the 3' untranslated region of C/EBPα. Furthermore, transfection of miR-326 into human adipose-derived stem cells caused a significant reduction in C/EBPα. Our results highlight the importance of miR-326 in adipogenic differentiation and provide a reliable basis for clinical treatment of adipose-related diseases. Anat Rec, 2019. © 2019 American Association for Anatomy.

15.
Environ Pollut ; 255(Pt 2): 113312, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31610503

RESUMO

Polycyclic aromatic hydrocarbons (PAHs), some of the most widespread organic contaminants, are highly toxic to soil microorganisms. Whether long-term polluted soils can still respond to the fresh input of pollutants is unknown. In this study, the soil enzyme activity, soil microbial community structure and function and microbial metabolism pathways were examined to systematically investigate the responses of soil microorganisms to fresh PAH stress. Microbial activity as determined by soil dehydrogenase and urease activity was inhibited upon microbe exposure to PAH stress. In addition, the soil microbial community and function were obviously shifted under PAH stress. Both microbial diversity and richness were decreased by PAH stress. Rhizobacter, Sphingobium, Mycobacterium, Massilia, Bacillus and Pseudarthrobacter were significantly affected by PAH stress and can be considered important indicators of PAH contamination in agricultural soils. Moreover, the majority of microbial metabolic function predicted to respond to PAH stress were affected adversely. Finally, soil metabolomics further revealed specific inhibition of soil metabolism pathways associated with fatty acids, carbohydrates and amino acids. Therefore, the soil metabolic composition distinctively changed, reflecting a change in the soil metabolism. In summary, fresh contaminant introduction into long-term polluted soils inhibited microbial activity and metabolism, which might profoundly affect the whole soil quality.

16.
Int J Biol Sci ; 15(10): 2128-2138, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31592122

RESUMO

With the increasing incidence of thoracic tumors, radiation therapy (RT) has become an important component of comprehensive treatment. RT improves survival in many cancers, but it involves some inevitable complications. Radiation-induced heart disease (RIHD) is one of the most serious complications. RIHD comprises a spectrum of heart disease including cardiomyopathy, pericarditis, coronary artery disease, valvular heart disease and conduction system abnormalities. There are numerous clinical manifestations of RIHD, such as chest pain, palpitation, and dyspnea, even without obvious symptoms. Based on previous studies, the pathogenesis of RIHD is related to the production and effects of various cytokines caused by endothelial injury, inflammatory response, and oxidative stress (OS). Therefore, it is of great importance for clinicians to identify the mechanism and propose interventions for the prevention of RIHD.

17.
Microbiologyopen ; : e942, 2019 Sep 30.
Artigo em Inglês | MEDLINE | ID: mdl-31568679

RESUMO

In this study, we investigated the physicochemical properties of soil, and the diversity and structure of the soil ammonia-oxidizing archaea (AOA) community, when subjected to fertilizer treatments for over 35 years. We collected soil samples from a black soil fertilization trial in northeast China. Four treatments were tested: no fertilization (CK); manure (M); nitrogen (N), phosphorus (P), and potassium (K) chemical fertilizer (NPK); and N, P, and K plus M (MNPK). We employed 454 high-throughput pyrosequencing to measure the response of the soil AOA community to the long-term fertilization. The fertilization treatments had different impacts on the shifts in the soil properties and AOA community. The utilization of manure alleviated soil acidification and enhanced the soybean yield. The soil AOA abundance was increased greatly by inorganic and organic fertilizers. In addition, the community Chao1 and ACE were highest in the MNPK treatment. In terms of the AOA community composition, Thaumarchaeota and Crenarchaeota were the main AOA phyla in all samples. Compared with CK and M, the abundances of Thaumarchaeota were remarkably lower in the MNPK and NPK treatments. There were distinct shifts in the compositions of the AOA operational taxonomic units (OTUs) under different fertilization management practices. OTU51 was the dominant OTU in all treatments, except for NPK. OTU79 and OTU11 were relatively abundant OTUs in NPK. Only Nitrososphaera AOA were tracked from the black soil. Redundancy analysis indicated that the soil pH and soil available P were the two main factors that affected the AOA community structure. The abundances of AOA were positively correlated with the total N and available P concentrations, and negatively correlated with the soil pH.

18.
Nanoscale ; 11(38): 17939-17946, 2019 Oct 03.
Artigo em Inglês | MEDLINE | ID: mdl-31553006

RESUMO

Supercabatteries have the characteristics of supercapacitors and batteries, namely high power and energy densities as well as long cycle life. To construct them, capacitor electrodes with wide potential windows and/or redox electrolytes are required. Herein, graphite@diamond nano-needles and an aqueous solution of Fe(CN)63-/4- are utilized as the capacitor electrode and the electrolyte, respectively. This diamond capacitor electrode has a nitrogen-doped diamond core and a nano-graphitic shell. In 0.05 M Fe(CN)63-/4- + 1.0 M Na2SO4 aqueous solution, the fabricated supercabattery has a capacitance of 66.65 mF cm-2 at a scan rate of 10 mV s-1. It is stable over 10 000 charge/discharge cycles. The symmetric supercabattery device assembled using a two-electrode system possesses energy and power densities of 10.40 W h kg-1 and 6.96 kW kg-1, respectively. These values are comparable to those of other energy storage devices. Therefore, diamond supercabatteries are promising for many industrial applications.

19.
Langmuir ; 35(40): 12955-12961, 2019 Oct 08.
Artigo em Inglês | MEDLINE | ID: mdl-31524400

RESUMO

We experimentally investigated the coalescence of two sessile microdrops on rigid surfaces with diverse wettability (macroscopic apparent water contact angles of θapp ≈ 13-110°) and on hydrophobic surfaces (θapp ≈ 110-124°) with very different stiffness properties (Young's moduli of E ≈ 1.1 MPa to 130 GPa). We show that the coalescence contains two fast regimes, in which a liquid meniscus bridging the parent droplets rapidly grows, forming a hemi-ellipsoidal droplet, and a slow regime, in which the merged hemi-ellipsoidal droplet relaxes to the equilibrium hemispherical cap. Whereas the fast bridging regimes last less than 2 ms and are almost independent of surface wettability and stiffness, the relaxation regime, which was only observed on sufficiently hydrophobic and rigid surfaces with low wetting hysteresis, continues for a few tens to several hundreds of milliseconds depending on surface properties. We further demonstrate that the slow droplet relaxation can be described neither by the bulk hydrodynamics nor by a microscopic model concerning liquid evaporation near the droplet edge, but by the molecular kinetic theory for the motion of the three-phase contact line.

20.
Bioresour Technol ; 293: 122081, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31479855

RESUMO

It is very important to utilize associated vegetable products as resources, especially in large-scale vegetable cultivation areas. In this study, pepper straw, a vegetable waste, was pyrolyzed into pepper straw biochars (PBs) to investigate their sorption potential for phthalate acid esters (PAEs). The results showed that PBs have porous structures and abundant surface functional groups. Dibutyl phthalate (DBP) and dimethyl phthalate (DMP) removal by PBs was divided into two stages, fast and slow sorption. The PBs pyrolyzed at 500 °C showed greater DBP and DMP sorption capacity than those pyrolyzed at 400 and 600 °C. Both chemical and physical sorption occurred in the whole sorption process of PAEs to PBs. It is proposed that converting pepper straw into biochars to use as sorbents could be an environmentally friendly way of vegetable waste resource utilization.


Assuntos
Ésteres , Ácidos Ftálicos , Adsorção , Carvão Vegetal , Dibutilftalato , Verduras , Água
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