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1.
Chemosphere ; 240: 124837, 2020 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-31542575

RESUMO

Substantial changes have occurred in hydrological situation of the Three Gorges Reservoir (TGR) after the operation of the Three Gorges project, as have the heavy metals (HMs) pollution characteristics. In this study, concentrations of Cu, Zn, Pb, Cr, and Cd in surface water and sediments of the TGR were determined during the water impoundment period (December 2015) and water drawdown period (June 2016). The index of geoaccumulation, principal component analysis (PCA), and correlation analysis were used to analyze HMs pollution characteristics. Results showed that HMs concentrations in surface water were much lower than the quality standards for drinking water and surface water of China. The pollution levels of HMs in sediments were nonpolluted for Cr, nonpolluted to moderately polluted for Cu, Zn, Pb, and moderately polluted for Cd. In the fluctuating backflow zone, HMs concentrations in sediments during the water drawdown period were lower than those during the water impoundment period, which was attributed to that faster flow velocity during the water drawdown period resulted in less deposition of suspended solids and faster release of HMs pollutants from sediments to water. HMs concentrations of sediments at sites M14 and M17 showed similar periodic changes to those at the fluctuating backflow zone, which might be attributed to the density-stratified flow in the adjacent upstream tributaries (Meixi River and Qinggan River, respectively). Correlation analysis and PCA analysis results showed that for the sediments, Cr came from natural sources, while Cu, Zn, Pb, and Cd mainly came from anthropogenic sources.

3.
Food Chem ; 305: 125476, 2020 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-31525589

RESUMO

Octenylsuccinate quinoa starch (OSQS) granule that stabilized Pickering emulsion gel with different gel networks by modulating the oil volume fraction (Φ) was developed as a carrier for lutein. Pickering emulsion gels stabilized by OSQS were achieved at Φ values ranging from 30% to 60%. Increasing Φ progressively increased the droplet size, storage modulus, and apparent viscosity, resulting in the formation of gel-like structure. Confocal laser scanning microscopy showed that OSQS formed a densely packed layer at the oil/water interface, the degree of aggregation between droplets increased, and the gel network enhanced through droplet flocculation with increasing Φ. After 31 days of storage, the retention index of lutein in the emulsion gel could reach 55.38%, and the corresponding half-life times increased from 12 to 41 days. This study will be useful for designing starch-based Pickering emulsion gel with tunable gel network and desirable characteristics as delivery carrier of sensitive bioactive compounds.

4.
J Nanosci Nanotechnol ; 20(5): 3047-3052, 2020 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-31635647

RESUMO

The g-C3N4/BiPO4 composites have been successfully synthesized via a one-pot hydrothermal process, which can be used to degrade the organic dyes (rhodamine B and methylene blue) under simulated sunlight irradiation. X-ray diffraction (XRD), scanning electron microscope (SEM), UV-Vis diffuse reflectance spectra and Fourier transform infrared (FTIR) spectroscopy have been employed to characterize the samples. The g-C3N4/BiPO4 composites exhibited higher photocatalytic activity than pure BiPO4. And the optimum photocatalyst shows the outstanding photocatalytic activity, which exhibited 99.0% and 86.6% decolorization rate of RhB and MB, respectively.

5.
Mater Sci Eng C Mater Biol Appl ; 106: 110159, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31753404

RESUMO

Stimuli-triggered drug delivery systems have been recognized as a crucial strategy to achieve on-demand drug release at the tumor for improving therapeutic efficacy. In this work, novel biocompatible and biodegradable reactive oxygen species (ROS)-responsive amino acid- based polymeric micelles were developed for tumor-specific drug release triggered by high ROS levels in cancer cells, which were composed of amphiphilic poly(aspartic acid) (PASP) derivatives (PASP-BSer) with phenylborate serine (BSer) side groups as the ROS-responsive unit. A series of PASP-BSer conjugates with different degree of substitution (DS) were synthesized, and their self-assembly and H2O2-responsive behaviors were investigated to optimize the structure of PASP-BSer. In vitro drug loading and release studies confirmed that the optimized PASP-BSer micelles could effectively encapsulate the model anticancer drug doxorubicin (Dox) and exhibit desirable H2O2-triggered release behaviors. More importantly, Dox-loaded PASP-BSer micelles showed high selective cytotoxicity against A549 cancer cells than L929 normal cells. Accordingly, PASP-BSer micelles have significant potential as on-demand drug carriers for anticancer therapy.

6.
J Hazard Mater ; 383: 121236, 2020 Feb 05.
Artigo em Inglês | MEDLINE | ID: mdl-31563046

RESUMO

Advanced oxidation methods based on photocatalysis and sulfate radicals have attached most interest towards contaminant degradation. However, there are a lack of coupling two methods in the field of pollutant degradation. In the present study, a new Bi2O3/CuNiFe LDHs composite was fabricated and it could efficiently activate persulfate (PS) for lomefloxacin (LOM) decomposition under simulated sunlight, in which 84.6% of LOM (10 mg·L-1) was degraded over 40 min with 0.4 g·L-1 of Bi2O3/CuNiFe LDHs composite and 0.74 mM of PS at natural pH. In addition, the Bi2O3/CuNiFe LDHs composite possessed good reusability and stability at least four runs. Moreover, active radical scavenging experiments indicated that hydroxyl radicals (HO·), sulfate radicals (SO4·-), superoxide radicals (O2·-) and hole (h+) were the main radicals under LOM degradation process. Subsequently, the possible degradation intermediates were determined and the decomposition pathways were put forward. At the same time, activated sludge inhibition experiments were performed to assess the variation of toxicity of LOM and its degradation intermediates during oxidation. Finally, possible reaction mechanism of Bi2O3/CuNiFe LDHs composite for PS activation under simulated sunlight was proposed.

7.
Enzyme Microb Technol ; 132: 109441, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31731964

RESUMO

D-allulose has received increasing attention due to its excellent physiological properties and commercial potential. The D-allulose 3-epimerase from Rhodopirellula baltica (RbDAEase) catalyzes the conversion of D-fructose to D-allulose. However, its poor thermostability has hampered its industrial application. Site-directed mutagenesis based on homologous structures in which the residuals on high flexible regions were substituted according to B-factors analysis, is an effective way to improve the thermostability and robustness of an enzyme. RbDAEase showed substrate specificity toward D-allulose with a Km of 58.57 mM and kcat of 1849.43 min-1. It showed a melting temperature (Tm) of 45.7 °C and half-life (t1/2) of 52.3 min at pH 8.0, 60 °C with 1 mM Mn2+. The Site-directed mutation L144 F strengthened the thermostability to a Δt1/2 of 50.4 min, ΔTm of 12.6 °C, and ΔT5060 of 22 °C. It also improved the conversion rate to 28.6%. Structural analysis reveals that a new hydrophobic interaction was formed by the mutation. Thus, site-directed mutagenesis based on B-factors analysis would be an efficient strategy to enhance the thermostability of designed ketose 3-epimerases.

8.
J Endocrinol ; 244(1): 223-236, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31648186

RESUMO

Obesity is a worldwide health problem. Semaphorins are involved in axonal guidance; however, the role of secretory semaphorin 3G (SEMA3G) in regulating adipocyte differentiation remains unclear. Microarray analysis showed that the SEMA3G gene was upregulated in an in vitro model of adipogenesis. In this study, SEMA3G was highly expressed in the white adipose tissue and liver. Analysis of 3T3-L1 cell and primary mouse preadipocyte differentiation showed that SEMA3G mRNA and protein levels were increased during the middle stage of cell development. In vitro experiments also showed that adipocyte differentiation was promoted by SEMA3G; however, SEMA3G inhibition using a recombinant lentiviral vector expressing a specific shRNA showed the opposite results. Mice were fed a chow or high-fat diet (HFD); knockdown of SEMA3G was found to inhibit weight gain, reduce fat mass in the tissues, prevent lipogenesis in the liver tissue, reduce insulin resistance and ameliorate glucose tolerance in HFD mice. Additionally, the effect of SEMA3G on HFD-induced obesity was activated through PI3K/Akt/GSK3ß signaling in the adipose tissue and the AMPK/SREBP-1c pathway in the liver. Moreover, the plasma concentrations of SEMA3G and leptin were measured in 20 obese and 20 non-obese human subjects. Both proteins were increased in obese subjects, who also exhibited a lower level of adiponectin and presented with insulin resistance. In summary, we demonstrated that SEMA3G is an adipokine essential for adipogenesis, lipogenesis, and insulin resistance and is associated with obesity. SEMA3G inhibition may, therefore, be useful for treating diet-induced obesity and its complications.

9.
Opt Express ; 27(20): 28618-28628, 2019 Sep 30.
Artigo em Inglês | MEDLINE | ID: mdl-31684610

RESUMO

Transparent conductive oxide (TCO) films showing epsilon near zero (ENZ) properties have attracted great research interest due to their unique property of electrically tunable permittivity. In this work, we report the effect of oxygen stoichiometry on the structure, optical and ENZ properties of indium tin oxide (ITO) films fabricated under different oxygen partial pressures. By using spectroscopic ellipsometry (SE) with fast data acquisition capabilities, we observed modulation of the material index and ENZ wavelength under electrostatic gating. Using a two-layer model based on Thomas-Fermi screening model and the Drude model, the optical constants and Drude parameters of the ITO thin films are determined during the gating process. The maximum carrier modulation amplitude ΔN of the accumulation layer is found to vary significantly depending on the oxygen stoichiometry. Under an electric field gate bias of 2.5 MV/cm, the largest ENZ wavelength modulation up to 27.9 nm at around 1550 nm is observed in ITO thin films deposited with oxygen partial pressure of P O 2 =10 Pa. Our work provides insights to the optical properties of ITO during electrostatic gating process for electro-optic modulators (EOMs) applications.

10.
Pharmacol Rep ; 71(6): 1244-1252, 2019 Jul 31.
Artigo em Inglês | MEDLINE | ID: mdl-31670061

RESUMO

BACKGROUND: Coumarin and 3,4-dihydroquinolinone nuclei are two heterocyclic rings that are important and widely exploited for the development of bioactive molecules. Here, we designed and synthesized a series of 3,4-dihydroquinolinone and coumarin derivatives (Compounds 8, 9, 11, 14, 15, 18-20, 23, 24 and 28 are new compounds) and studied their antidepressant activities. METHODS: Forced swimming test (FST) and tail suspension test (TST) were used to evaluate the antidepressant activity of the target compounds. The most active compound was used to evaluate the exploratory activity of the animals by the open-field test. 5-HT concentration was estimated to evaluate if the compound has an effect on the mouse brain, by using ELISA. A 5-HT1A binding assay was also performed. The biological activities of the compounds were verified by molecular docking studies. The physicochemical and pharmacokinetic properties of the target compounds were predicted by Discovery Studio and ChemBioDraw Ultra. RESULTS: Of all the compounds tested, compound 7 showed the best antidepressant activity, which decreased the immobility time by 65.52 s in FST. However, in the open-field test, compound 7 did not affect spontaneous activity. The results of 5-HT concentration estimation in vivo showed that compound 7 may have an effect on the mouse brain. Molecular docking results indicated that compound 7 showed significant interactions with residues at the 5-HT1A receptor using homology modeling. The results show that compound 7 exhibits good affinity for the 5-HT1A receptor. CONCLUSION: Coumarin and 3,4-dihydroquinolinone derivatives synthesized in this study have a significant antidepressant activity. These findings can be useful in the design and synthesis of novel antidepressants.

11.
Plant Cell Rep ; 2019 Nov 12.
Artigo em Inglês | MEDLINE | ID: mdl-31713664

RESUMO

KEY MESSAGE: GbWRKY1 can function as a negative regulator of ABA signaling via JAZ1 and ABI1, with effects on salt and drought tolerance. WRKY transcription factors play important roles in plant development and stress responses. GbWRKY1 was initially identified as a defense-related gene in cotton and negatively regulates the response to fungal pathogens by activating the expression of JAZ1. Here, we characterized the role of GbWRKY1, an orthologue of the Arabidopsis gene AtWRKY75, in abiotic stress (salt and drought) and established novel connection between JAZ1 and ABA signaling in Arabidopsis. GbWRKY1 is nucleus localized and its expression is significantly induced by treatment with ABA and osmotic stresses NaCl and PEG. Increased levels of expression of GbWRKY1 in transgenic Arabidopsis enhance sensitivity to salt and drought as revealed by seed germination tests and soil stress experiments. Similarly, GbWRKY1 overexpression cotton plants also display increased sensitivity to PEG treatment and drought. Expression analysis shows that the induction of two ABA responsive genes, RAB18 and RD29A by NaCl, mannitol, and ABA treatment is significantly impaired in GbWRKY1 overexpression Arabidopsis lines. GbWRKY1 overexpression Arabidopsis displays a strong ABA-insensitive phenotype at both germination and early stages of seedling development. Further genetic evidence suggested that the ABA-insensitive phenotype of GbWRKY1 overexpression Arabidopsis was dependent on JAZ1, and overexpression of JAZ1 also displayed an ABA-insensitive phenotype. In addition, yeast two hybrid and bimolecular fluorescence complementation assays showed that JAZ1 directly interacts with ABI1, a key negative regulator of ABA signaling. We, therefore, demonstrate that GbWRKY1 acts as a negative regulator of ABA signaling, through an interaction network involving JAZ1 and ABI1, to regulate salt and drought tolerance.

12.
Spinal Cord ; 2019 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-31676870

RESUMO

STUDY DESIGN: Cross-sectional self-report assessment. Econometric modeling. OBJECTIVES: Identify the relationship of multiple pain indicators, prescription pain medication, nonprescription opioid use, and multiple indicators of quality employment among those with spinal cord injury (SCI). SETTING: Data were collected at a medical university in the Southeastern United States (US). METHODS: Participants included 4670 adults with traumatic SCI of at least one-year duration who were enrolled in a study of health and longevity. They were identified from three sources including a specialty hospital and two population-based state SCI surveillance systems. Econometric modeling was used for three outcome variables: employment status, hours per week spent working, and earnings. RESULTS: Several pain parameters were significantly related to multiple employment outcomes. Prescription medication to treat pain was associated with lower odds of employment, fewer hours working, and lower conditional earnings. Nonprescription opioid use was only related to fewer hours working. Painful days, number of painful conditions, and pain intensity were all related to employment outcomes, but the pattern varied by outcome. The number of painful conditions was most consistently related to employment. Multiple demographic, injury, and educational factors were related to employment, with better outcomes among those with less severe SCI and greater educational achievements. CONCLUSIONS: The presence of significant pain and use of either prescription pain medications or the use of nonprescription opioids may have a significant adverse effect on both the probability of employment and quality of employment. Rehabilitation and vocational professionals should routinely assess pain and associated medications in vocational and career planning.

13.
Environ Int ; : 105000, 2019 Nov 04.
Artigo em Inglês | MEDLINE | ID: mdl-31699440

RESUMO

Inhalation from ambient air and cigarette smoke is a common route of human exposure to polycyclic aromatic hydrocarbons (PAHs). Little information is available regarding hepatotoxicities of inhaled PAHs so for. In this study, we evaluated the toxic effects of intratracheally instilled benzo[a]pyrene (B[a]P) on hepatic lipid metabolism of C57BL/6 mice at relevant environmental exposure levels by using two different mass-based lipidomics approaches. The results of mass spectrometry imaging analysis showed that both the abundance and spatial distribution of several lysophosphatidylcholine (LysoPC), phosphatidylcholine (PC) and sphingomyelin (SM) in the liver section were different and changed after inhalation exposure to B[a]P. Liquid chromatography coupled with mass spectrometry-based lipidomics analysis and multivariate statistical analysis found that B[a]P exposure markedly altered glycerophospholipids, glycerolipids, and fatty acid metabolism in the mouse liver, with increasing of triacylglycerol (TG), phosphatidylinositol (PI) and PC, and decreasing of LysoPCs phosphatidylethanolamines (PEs), lysophosphatidylethanolamine (LysoPEs), free fatty acids (FFAs) and eicosanoids. B[a]P-induced lipid metabolic disorders showed a time-dependent effect, which generated three response trajectories with different change trends. Consequently, B[a]P exposure induced alteration of hepatic lipids by promoting the uptake from blood or the biosynthesis and transformation in the liver, might contribute to non-alcoholic fatty liver disease, hepatocyte membrane injury, inflammation, and signal system disturbance.

14.
Cytotherapy ; 2019 Nov 05.
Artigo em Inglês | MEDLINE | ID: mdl-31699595

RESUMO

Systemic chemotherapy is a conventional and important strategy for inhibition of cancer progression, but it is usually accompanied by various adverse effects. Targeting drug delivery systems, effective tools to avoid the adverse effects of chemotherapy, have been intensively studied and developed. Recently, the emerging application of exosomes and exosome-mimics (small extracellular vesicles [sEVs]) in targeted drug delivery and therapeutics has been widely appreciated. The sEVs-based delivery system comprises three basic components: vesicles, cargoes and surface decorations. In this article, we review the current status, existing challenges and future directions in this field from the following aspects: selection and production of vesicles; cargoes and methods to load them into vesicles; modifications to the surfaces of vesicles; as well as ways to prolong the half-life of sEVs in the circulation. Existing and emerging data indicate that sEVs are promising nanocarriers for clinical use, but additional efforts are needed to translate research findings into therapeutic products.

15.
J Chromatogr A ; : 460628, 2019 Oct 16.
Artigo em Inglês | MEDLINE | ID: mdl-31753484

RESUMO

Hawthorn is a popular functional food. In China, Crataegus pinnatifida Bunge. and C. pinnatifida Bge. var. major N. E. Brown are two major species that are used for the preparation of hawthorn products. Accordingly, it is crucial to explore the chemical differences between these two species for the market standardization of hawthorn products. In this study, we integrated manual annotation with untargeted metabolomics based on ultra-high performance liquid chromatography coupled with quadrupole time-of-flight tandem mass spectrometry for compound characterization and discrimination of the two hawthorn species. We characterized 78 compounds in the two species including saccharides, glycosides, organic acids, phenols, flavonoids and triterpenoids. Moreover, 47 differential compounds and 17 false positive ions were recognized and fully reviewed. The 47 identified compounds were then used to build a partial least squares discriminant analysis model that successfully discriminated C. pinnatifida Bge. and C. pinnatifida Bge. var. major N.E.Br.

16.
Orthop Surg ; 2019 Nov 22.
Artigo em Inglês | MEDLINE | ID: mdl-31755242

RESUMO

Total hip arthroplasty (THA) of Crowe type IV developmental dysplasia of the hip (DDH) is challenging. Although traditional (lateral, posterolateral, and posterior) THA approaches have been used with great anatomic success, they damage periarticular muscles, which are already quite weak in type IV DDH. The recently developed direct anterior approach (DAA) can provide an inter-nerve and inter-muscle approach for THA of type IV dysplasia hips. However, femur exposure with the DAA could be difficult during surgery and it is hard to apply femoral shortening osteotomy. THA techniques used for type IV DDH include anatomic hip center techniques (true acetabular reconstruction) and high hip center techniques, wherein an acetabulum is reconstructed above the original one. Although anatomic construction of the hip center is considered "the gold standard" treatment, it is impossible if the anatomical acetabular is too small and shallow. Procedures used to support type IV DDH reduction with anatomic hip center techniques include greater trochanter osteotomy, lesser trochanter osteotomy, and subtrochanteric osteotomy. However, these techniques have yet to be standardized, and it is unclear which is best for type IV DDH. One-state and two-state non-osteotomy reduction techniques have also been introduced to treat type IV DDH. Potential complications of THA performed in patients with type IV DDH include leg length discrepancy (LLD), peri-operative femur fracture, nonunion of the osteotomy site, and nerve injury. It is worth noting that nowadays an increasing number of Crowe type IV DDH patients are more sensitive to postoperative LLD.

17.
BMC Pediatr ; 19(1): 423, 2019 Nov 11.
Artigo em Inglês | MEDLINE | ID: mdl-31707983

RESUMO

BACKGROUND: The initial episode of angioedema in children can be potential life-threatening due to the lack of prompt identification and treatment. We aimed to analyze the factors predicting the severity and outcomes of the first attack of acute angioedema in children. METHODS: This was a retrospective study with 406 children (< 18 years) who presented in the emergency department (ED) with an initial episode of acute angioedema and who had subsequent follow-up visits in the out-patient department from January 2008 to December 2014. The severity of the acute angioedema was categorized as severe (requiring hospital admission), moderate (requiring a stay in the short-term pediatric observation unit [POU]), or mild (discharged directly from the ED). The associations among the disease severity, patient demographics and clinical presentation were analyzed. RESULT: In total, 109 (26.8%) children had severe angioedema, and the majority of those children were male (65.1%). Most of the children were of preschool age (56.4%), and only 6.4% were adolescents. The co-occurrence of pyrexia or urticaria, etiologies of the angioedema related to medications or infections, the presence of respiratory symptoms, and a history of allergies (asthma, allergic rhinitis) were predictors of severe angioedema (all p < 0.05). Finally, the duration of angioedema was significantly shorter in children who had received short-term POU treatment (2.1 ± 1.1 days) than in those who discharged from ED directly (2.3 ± 1.4 days) and admitted to the hospital (3.5 ± 2.0 days) (p < 0.001). CONCLUSION: The co-occurrence of pyrexia or urticaria, etiologies related to medications or infections, the presence of respiratory symptoms, and a history of allergies were predictors of severe angioedema. More importantly, short-term POU observation and prompt treatment might be benefit for patients who did not require hospital admission.

18.
Res Social Adm Pharm ; 2019 Nov 09.
Artigo em Inglês | MEDLINE | ID: mdl-31734101

RESUMO

BACKGROUND: Treating cancer and existing chronic comorbidities requires a dynamic mix of primary care and specialist providers. However, little is known regarding primary care physicians' (PCPs) and oncologists' comfort level prescribing for comorbid conditions. OBJECTIVES: The objectives of this study were to describe oncologists' and PCPs': 1) comfort-level prescribing, 2) perceptions of providers' role in prescribing cardiometabolic and psychiatric medications in persons with cancer and comorbidity, and 3) provider factors associated with comfort-levels. METHODS: This cross-sectional online survey examined responses from practicing U.S. PCPs and oncologists. A 33-question survey was used to assess PCPs' and oncologists' comfort-levels for prescribing 6 classes of medications used to treat common comorbid cardiometabolic or psychiatric conditions. Using t-tests, chi-square tests, or Fisher's Exact tests, physicians' own comfort and comfort with other physicians prescribing medications for shared patients were compared between PCPs and oncologists. Linear regression models were used to analyze predictors of comfort-level scale score for prescribing medications. RESULTS: Oncologists were more comfortable with PCPs initiating or refilling antidiabetics, antihyperlipidemics, antidepressants, and antipsychotics, and PCPs were more comfortable initiating antihypertensives, antidiabetics, antihyperlipidemics, antidepressants, and antipsychotics themselves as opposed to having an oncologist initiate or refill these medications. Compared to oncologists, PCPs reported a 32.3% higher comfort-level for initiating cardiometabolic medications (Adjusted Coefficient (standard error) = 0.323 (0.033), p < 0.001), and a 25.0% higher comfort-level for initiating psychiatric medications in cancer patients (Adjusted Coefficient (standard error) = 0.250 (0.030), p < 0.001), after controlling for prescriber demographics and practice site characteristics. CONCLUSIONS: Findings suggest that when a cancer diagnosis is made for patients with pre-existing cardiometabolic or psychiatric conditions, oncologists prefer PCPs to manage these medications. This enhanced understanding of PCPs' and oncologists' comfort managing these medications may help develop a standard for defining physician roles in medication therapy as part of a shared care plan for patients with cancer and comorbidities.

19.
Adv Mater ; : e1905645, 2019 Nov 18.
Artigo em Inglês | MEDLINE | ID: mdl-31736170

RESUMO

A ternary structure has been demonstrated as being an effective strategy to realize high power conversion efficiency (PCE) in organic solar cells (OSCs); however, general materials selection rules still remain incompletely understood. In this work, two nonfullerene small-molecule acceptors 3TP3T-4F and 3TP3T-IC are synthesized and incorporated as a third component in PM6:Y6 binary blends. The photovoltaic behaviors in the resultant ternary OSCs differ significantly, despite the comparable energy levels. It is found that incorporation of 15% 3TP3T-4F into the PM6:Y6 blend results in facilitating exciton dissociation, increasing charge transport, and reducing trap-assisted recombination. All these features are responsible for the enlarged PCE of 16.7% (certified as 16.2%) in the PM6:Y6:3TP3T-4F ternary OSCs, higher than that (15.6%) in the 3TP3T-IC containing ternary devices. The performance differences are mainly ascribed to the compatibility between the third component and the host materials. The 3TP3T-4F guest acceptor exhibits an excellent compatibility with Y6, tending to form well-mixed phases in the ternary blend without disrupting the favored bicontinuous transport networks, whereas 3TP3T-IC displays a morphological incompatibility with Y6. This work highlights the importance of considering the compatibility for materials selection toward high-efficiency ternary organic OSCs.

20.
Sci Total Environ ; 695: 133963, 2019 Dec 10.
Artigo em Inglês | MEDLINE | ID: mdl-31756847

RESUMO

A kind of heterogeneous catalyst, FeMn layered double hydroxide (Fe-Mn-LDH), was fabricated by coprecipitation process and used as PMS activator to degrade a novel organic pollutant octadecylamine (ODA). And the X-ray diffraction (XRD), scanning electron microscope (SEM), transmission electron microcopy (TEM), Mapping and X-ray photoelectron spectra (XPS) measurements were utilized to characterize the fresh and used Fe-Mn-LDH. After a serious of degradation experiments, it was clearly to see that the activator possessed excellent activation property for PMS and was capable of removing 85% ODA (10 mg·L-1) within 25 min obviously higher than pure PMS. Moreover, the effect of some elements (such as PMS consumption, catalyst consistence and initial pH value), different reaction system and catalyst repeatability on ODA degradation were also explored. And by identification of main radical experiment, SO4- and HO were both confirmed the primary radicals. What's more, extra anion and nature organic matter (NOM) addition experiment displayed that NOM, NO3- and CO32- perform a negative effect on ODA degradation but Cl- could promote it. In addition, repeated experiments and metal leaching after degradation showed good stability of Fe-Mn-LDH. Finally, based on the XPS and Gas Chromatography-Mass Spectrometer (GS-MS) technology, the possible degradation mechanism and pathway were proposed.

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