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1.
Artigo em Inglês | MEDLINE | ID: mdl-38658508

RESUMO

The transformation of solid wastes from industrial production into effective adsorbents could significantly contribute to wastewater treatment. In this study, after acidizing and burning soft scale (SS) from coal gasification system, two magnetic adsorbents (mag-ASS and mag-BASS) were prepared via the combination of magnetite with ultrasonic, respectively. The treatment effects of mag-ASS and mag-BASS were then investigated for simulated wastewater containing macromolecular organic matter [i.e., methylene blue (MB)] and Ca2+. The results indicated that the pseudo second order kinetic, Elovich, Freundlich, Langmuir and Temkin model could well describe the adsorption behavior of MB and Ca2+ onto mag-ASS and mag-BASS. The maximum adsorption capacities of mag-ASS for MB and mag-BASS for Ca2+ were 600.53 mg/g and 102.54 mg/g, respectively. Surprisingly, the adsorption abilities of mag-ASS for MB and mag-BASS for Ca2+ show significantly higher than the others. The adsorption mechanisms of MB mainly included electrostatic interaction, π-π conjugate interaction and cation exchange, while those of Ca2+ were mainly electrostatic interaction and cation exchange. The diffusion of MB and Ca2+ onto the magnetic adsorbents might be controlled by the combined effects of intraparticle and liquid film diffusion. There was no significant reduction in adsorption capacity after 8 cycles of adsorption and desorption, indicating that SS-based magnetic adsorbents had good recyclability and stability. Moreover, the removal efficiency of mag-BASS for total hardness and total organic carbon in real coal gasification gray water (CGGW) was 82.60 and 64.10%, respectively. The treatment of CGGW and the resource of wastes would significantly promote the reasonable disposal of coal gasification scales.

2.
Org Lett ; 26(10): 2108-2113, 2024 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-38440974

RESUMO

A metal-free photosensitized 1,2-imino-sulfamoylation of olefins by employing a tailor-made sulfamoyl carbamate as the difunctionalization reagent has been established. This protocol exhibits versatility across a broad substrate scope, including aryl and aliphatic alkenes, leading to the synthesis of diverse ß-imino sulfonamides in moderate to good yields. This method is characterized by its metal-free reaction system, mild reaction conditions, excellent regioselectivity, and high atom economy, serving as a promising platform for the preparation of ß-amino sulfonamide-containing molecules, particularly in the context of drug discovery.

3.
Molecules ; 29(5)2024 Mar 03.
Artigo em Inglês | MEDLINE | ID: mdl-38474646

RESUMO

Food-derived angiotensin-I-converting enzyme (ACE)-inhibitory peptides have gained attention for their potent and safe treatment of hypertensive disorders. However, there are some limitations of conventional methods for preparing ACE-inhibitory peptides. In this study, in silico hydrolysis, the quantitative structure-activity relationship (QSAR) model, LC-MS/MS, inhibition kinetics, and molecular docking were used to investigate the stability, hydrolyzability, in vitro activity, and inhibition mechanism of bioactive peptides during the actual hydrolysis process. Six novel ACE-inhibitory peptides were screened from the Larimichthys crocea protein (LCP) and had low IC50 values (from 0.63 ± 0.09 µM to 10.26 ± 0.21 µM), which were close to the results of the QSAR model. After in vitro gastrointestinal simulated digestion activity of IPYADFK, FYEPFM and NWPWMK were found to remain almost unchanged, whereas LYDHLGK, INEMLDTK, and IHFGTTGK were affected by gastrointestinal digestion. Meanwhile, the inhibition kinetics and molecular docking results were consistent in that ACE-inhibitory peptides of different inhibition forms could effectively bind to the active or non-central active centers of ACE through hydrogen bonding. Our proposed method has better reproducibility, accuracy, and higher directivity than previous methods. This study can provide new approaches for the deep processing, identification, and preparation of Larimichthys crocea.


Assuntos
Inibidores da Enzima Conversora de Angiotensina , Peptidil Dipeptidase A , Inibidores da Enzima Conversora de Angiotensina/química , Simulação de Acoplamento Molecular , Peptidil Dipeptidase A/metabolismo , Cromatografia Líquida , Reprodutibilidade dos Testes , Espectrometria de Massas em Tandem , Peptídeos/química , Angiotensinas
4.
CNS Neurosci Ther ; 30(3): e14650, 2024 03.
Artigo em Inglês | MEDLINE | ID: mdl-38514905

RESUMO

AIMS: To explore the pharmacological treatment of vascular depression (VaDep) and whether the blood levels of neurotransmitters can reflect the VaDep severity. METHODS: VaDep patients with somatic symptoms were enrolled and randomly received venlafaxine + tandospirone (Combined Group) or venlafaxine (Monotherapy Group). The treatment efficacy was assessed by Hamilton Depression Scale (HAMD), Hamilton Anxiety Scale (HAMA), and Patient Health Questionnaire-15 (PHQ-15). The levels of blood monoamine neurotransmitters were measured by enzyme-linked immunosorbent assay. RESULTS: Both groups reported a progressive decrease in HAMD, HAMA, and PHQ-15 scores to below the baseline after the respective treatment. Compared with the Monotherapy Group, the Combined Group reported a significant decrease in HAMD score at week 2 and markedly lower HAMA and PHQ-15 scores at weeks 1, 2, 4, and 8. Both groups showed a decrease in the levels of blood monoamine neurotransmitters at weeks 4 and 8 when compared with the baseline. A strong positive association was evident between the plasma 5-HT levels and the HAMD score. CONCLUSION: The combined therapy rapidly acts on VaDep comorbid with anxiety and somatic symptoms and significantly alleviates the anxiety and somatic symptoms. The plasma levels of 5-HT may serve as potential objective candidates in evaluating VaDep severity and the efficacy of the undertaken treatment regimen.


Assuntos
Ansiolíticos , Isoindóis , Sintomas Inexplicáveis , Piperazinas , Pirimidinas , Depressão Vascular , Humanos , Citratos , Depressão/tratamento farmacológico , Inibidores Seletivos de Recaptação de Serotonina , Serotonina , Resultado do Tratamento , Cloridrato de Venlafaxina/uso terapêutico , Quimioterapia Combinada/efeitos adversos
5.
Food Chem ; 447: 138873, 2024 Jul 30.
Artigo em Inglês | MEDLINE | ID: mdl-38452536

RESUMO

Food-derived angiotensin-converting enzyme-inhibitory (ACE-I) peptides have attracted extensive attention. Herein, the ACE-I peptides from Scomber japonicus muscle hydrolysates were screened, and their mechanisms of action and inhibition stability were explored. The quantitative structure-activity relationship (QSAR) model based on 5z-scale metrics was developed to rapidly screen for ACE-I peptides. Two novel potential ACE-I peptides (LTPFT, PLITT) were predicted through this model coupled with in silico screening, of which PLITT had the highest activity (IC50: 48.73 ± 7.59 µM). PLITT inhibited ACE activity with a mixture of non-competitive and competitive mechanisms, and this inhibition mainly contributed to the hydrogen bonding based on molecular docking study. PLITT is stable under high temperatures, pH, glucose, and NaCl. The zinc ions (Zn2+) and copper ions (Cu2+) enhanced ACE-I activity. The study suggests that the QSAR model is effective in rapidly screening for ACE-I inhibitors, and PLITT can be supplemented in foods to lower blood pressure.


Assuntos
Hidrolisados de Proteína , Relação Quantitativa Estrutura-Atividade , Simulação de Acoplamento Molecular , Hidrolisados de Proteína/farmacologia , Hidrolisados de Proteína/química , Peptídeos/farmacologia , Peptídeos/química , Músculos/metabolismo , Íons , Angiotensinas , Peptidil Dipeptidase A/metabolismo
6.
Small ; : e2311561, 2024 Mar 28.
Artigo em Inglês | MEDLINE | ID: mdl-38546001

RESUMO

Balancing the rigid backbones and flexible side chains of light-harvesting materials is crucially important to reach optimized intermolecular packing, micromorphology, and thus photovoltaic performance of organic solar cells (OSCs). Herein, based on a distinctive CH-series acceptor platform with 2D conjugation extended backbones, a series of nonfullerene acceptors (CH-6F-Cn) are synthesized by delicately tuning the lengths of flexible side chains from n-octyl to n-amyl. A systemic investigation has revealed that the variation of the side chain's length can not only modulate intermolecular packing modes and crystallinity but also dramatically improve the micromorphology of the active layer and eventual photovoltaic parameters of OSCs. Consequently, the highest PCE of 18.73% can be achieved by OSCs employing D18:PM6:CH-6F-C8 as light-harvesting materials.

7.
Sci Total Environ ; 922: 171339, 2024 Apr 20.
Artigo em Inglês | MEDLINE | ID: mdl-38428595

RESUMO

Inappropriate sterilization strategies inhibit microalgal growth when culturing microalgae with anaerobic digestate. This study aimed to scientifically select a low-cost disinfection pretreatment of anaerobic digestate for large-scale microalgae cultivations. In this work, three different methods, including autoclaving, ultraviolet or NaClO treatments, were employed to sterilize the municipal anaerobic digestate. Scenedesmus quadricauda was then cultured in diluted liquid digestate for the simultaneous lipid production and nutrient removal. The results indicated that the growth of S. quadricauda was inhibited after NaClO treatment due to the residual free chlorine. The 15-min ultraviolet effectively mitigated microbial contamination and increasing nutrient availability, enhancing the electron transport of microalgal photosynthesis. After 6-days cultivation, the microalgal biomass concentration of the ultraviolet group was 1.09 g/L, comparable to that of the autoclaving group (1.15 g/L). High nutrient removal efficiency was observed: COD (93.30 %), NH4+-N (92.56 %), TN (85.82 %) and TP (95.12 %). Moreover, S. quadricauda outcompeted the indigenous microorganisms, contributing to its dominance in the culture system of ultraviolet group. The facultative anaerobe Comamonadaceae and aerobes Moraxellaceae, rather than strict anaerobe Paludibacteraceae and Bacteroidetes_vadinHA17, played vital roles in synergistic removal of contaminants by bacteria and algae. The potential competition for nitrogen and phosphorus by bacteria contributed to the ultraviolet group having the greatest lipid content (48.19 %). Therefore, this work suggested using 15-min ultraviolet treatment for anaerobic digestate in large-scale microalgae cultivation.


Assuntos
Microalgas , Scenedesmus , Raios Ultravioleta , Anaerobiose , Bactérias , Biomassa , Nitrogênio , Bacteroidetes , Lipídeos
8.
Natl Sci Rev ; 11(3): nwad311, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38312386

RESUMO

Optical communication is a particularly compelling technology for tackling the speed and capacity bottlenecks in data communication in modern society. Currently, the silicon photodetector plays a dominant role in high-speed optical communication across the visible-near-infrared spectrum. However, its intrinsic rigid structure, high working bias and low responsivity essentially limit its application in next-generation flexible optoelectronic devices. Herein, we report a narrow-bandgap non-fullerene acceptor (NFA) with a remarkable π-extension in the direction of both central and end units (CH17) with respect to the Y6 series, which demonstrates a more effective and compact 3D molecular packing, leading to lower trap states and energetic disorders in the photoactive film. Consequently, the optimized solution-processed organic photodetector (OPD) with CH17 exhibits a remarkable response time of 91 ns (λ = 880 nm) due to the high charge mobility and low parasitic capacitance, exceeding the values of most commercial Si photodiodes and all NFA-based OPDs operating in self-powered mode. More significantly, the flexible OPD exhibits negligible performance attenuation (<1%) after bending for 500 cycles, and maintains 96% of its initial performance even after 550 h of indoor exposure. Furthermore, the high-speed OPD demonstrates a high data transmission rate of 80 MHz with a bit error rate of 3.5 [Formula: see text] 10-4, meaning it has great potential in next-generation high-speed flexible optical communication systems.

9.
Sci Bull (Beijing) ; 69(7): 968-977, 2024 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-38331705

RESUMO

Lake-effect snowfall (LES) occurs when cold air moves across open lakes. LES is expected to occur more frequently over the TP, due to the intensified lake expansion caused by intensified global warming. Thus, there is an urgent need to comprehensively assess the LES over the TP. Here, we revealed that the LES is triggered by westerly southward shift leading to the drop in air temperature and is positively correlated with lake area, wind speed and longitude across 12 large lakes (>300 km2) based on satellite observations and reanalysis data. Using a sensitivity model simulation, we determined that large lakes in the southern TP contributed to more than 50% of the snowfall in the downwind area in 2013. Projections indicate that the westerly-triggered LES will increase under the future RCP4.5 climate warming scenario, highlighting the importance of developing adaptive policies to address the growing risks associated with future LES.

10.
Antimicrob Agents Chemother ; 68(3): e0117523, 2024 Mar 06.
Artigo em Inglês | MEDLINE | ID: mdl-38259089

RESUMO

Staphylococcus aureus sequence type (ST) 5 has spread worldwide; however, phylogeographic studies on the evolution of global phylogenetic and Asian clades of ST5 are lacking. This study included 368 ST5 genome sequences, including 111 newly generated sequences. Primary phylogenetic analysis suggested that there are five clades, and geographical clustering of ST5 methicillin-resistant S. aureus (MRSA) was linked to the acquisition of S. aureus pathogenicity islands (SaPIs; enterotoxin gene island) and integration of the prophage φSa3. The most recent common ancestor of global S. aureus ST5 dates back to the mid-1940s, coinciding with the clinical introduction of penicillin. Bayesian phylogeographic inference allowed to ancestrally trace the Asian ST5 MRSA clade to Japan, which may have spread to major cities in China and Korea in the 1990s. Based on a pan-genome-wide association study, the emergence of Asian ST5 clades was attributed to the gain of prophages, SaPIs, and plasmids, as well as the coevolution of resistance genes. Clade IV displayed greater genomic diversity than the Asian MRSA clades. Collectively, our study provides in-depth insights into the global evolution of S. aureus ST5 mainly in China and the United States and reveals that different S. aureus ST5 clades have arisen independently in different parts of the world, with limited geographic dispersal across continents.


Assuntos
Staphylococcus aureus Resistente à Meticilina , Infecções Estafilocócicas , Humanos , Staphylococcus aureus/genética , Staphylococcus aureus Resistente à Meticilina/genética , Filogenia , Estudo de Associação Genômica Ampla , Teorema de Bayes , Genótipo , Infecções Estafilocócicas/tratamento farmacológico , Infecções Estafilocócicas/epidemiologia , Variação Genética/genética
11.
J Adv Res ; 55: 119-129, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-36889461

RESUMO

INTRODUCTION: Previous studies have evaluated metagenomic next-generation sequencing (mNGS) of cell-free DNA (cfDNA) for pathogen detection in blood and body fluid samples. However, no study has assessed the diagnostic efficacy of mNGS using cellular DNA. OBJECTIVES: This is the first study to systematically evaluate the efficacy of cfDNA and cellular DNA mNGS for pathogen detection. METHODS: A panel of seven microorganisms was used to compare cfDNA and cellular DNA mNGS assays concerning limits of detection (LoD), linearity, robustness to interference, and precision. In total, 248 specimens were collected between December 2020 and December 2021. The medical records of all the patients were reviewed. These specimens were analysed using cfDNA and cellular DNA mNGS assays, and the mNGS results were confirmed using viral qPCR, 16S rRNA, and internal transcribed spacer (ITS) amplicon next-generation sequencing. RESULTS: The LoD of cfDNA and cellular DNA mNGS was 9.3 to 149 genome equivalents (GE)/mL and 27 to 466 colony-forming units (CFU)/mL, respectively. The intra- and inter-assay reproducibility of cfDNA and cellular DNA mNGS was 100%. Clinical evaluation revealed that cfDNA mNGS was good at detecting the virus in blood samples (receiver operating characteristic (ROC) area under the curve (AUC), 0.9814). In contrast, the performance of cellular DNA mNGS was better than that of cfDNA mNGS in high host background samples. Overall, the diagnostic efficacy of cfDNA combined with cellular DNA mNGS (ROC AUC, 0.8583) was higher than that of cfDNA (ROC AUC, 0.8041) or cellular DNA alone (ROC AUC, 0.7545). CONCLUSION: Overall, cfDNA mNGS is good for detecting viruses, and cellular DNA mNGS is suitable for high host background samples. The diagnostic efficacy was higher when cfDNA and cellular DNA mNGS were combined.


Assuntos
Líquidos Corporais , Ácidos Nucleicos Livres , Humanos , RNA Ribossômico 16S/genética , Reprodutibilidade dos Testes , Sequenciamento de Nucleotídeos em Larga Escala , Ácidos Nucleicos Livres/genética , DNA
12.
J Med Educ Curric Dev ; 10: 23821205231219396, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-38152834

RESUMO

Objectives: The routine teaching mode of diabetes mellitus (DM) is divided into various sub-majors of medical laboratory, which is not conducive to clinical laboratory physicians quickly mastering relevant knowledge. A novel DM laboratory testing pathway is established to improve teaching efficiency and enhance the effects of talent cultivation in laboratory medicine. Methods: The guidelines and expert consensuses of DM were gathered from professional websites and databases. The clinical laboratory diagnostic pathway was formulated, and the questionnaire and mutual evaluation were used to evaluate the teaching effectiveness of 8-year undergraduate students enrolled in 2018 and enrolled in 2019, respectively. Results: Clinical laboratory physicians developed and approved the DM clinical laboratory diagnostic pathway, which included the entire process of DM diagnosis and differential diagnosis, drug selection, treatment impact monitoring, prognosis evaluation, etc. The results of the questionnaires showed that, in comparison to the teaching mode used with the students enrolled in 2018 and enrolled in 2019, the percentages of more improvement and significant improvement were significantly increased (P < 0.01) and the percentages of no improvement and slight improvement were significantly decreased (P < 0.01). Following the instruction of the DM clinical laboratory diagnostic route, the results were greatly improved, including points emphasized and the accuracy of responding to questions, among other things, according to the teachers' and students' mutual evaluation (P < 0.05). Conclusions: To enhance the teaching quality in laboratory medicine, it is required to build the disease clinical laboratory diagnostic pathway for a novel teaching method. This may boost teachers' and students' confidence and broaden their knowledge.

13.
Org Lett ; 25(49): 8824-8828, 2023 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-38032230

RESUMO

Herein, a visible-light-induced nickel-catalyzed cross-coupling of aryl bromide with nitrile has been reported. By utilization of readily available nitriles as carbonyl precursors, a range of structurally diverse aryl ketones were facilely constructed. The synthetic simplicity, mild reaction conditions, and acidic functional group tolerance would broaden the synthetic utilities of this developed protocol as an expedient alternative to Grignard/organolithium protocols.

14.
EBioMedicine ; 98: 104858, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37925777

RESUMO

BACKGROUND: Nanopore metagenomics has been used for infectious disease diagnosis for bacterial pathogens. However, this technology currently lacks comprehensive performance studies in clinical settings for simultaneous detection of bacteria, fungi, and viruses. METHODS: We developed a dual-process of Nanopore sequencing for one sample, with unbiased metagenomics in Meta process and target enrichment in Panel process (Nanopore Meta-Panel process, NanoMP) and prospectively enrolled 450 respiratory specimens from multiple centers. The filter system of pathogen detection was established with machine learning and receiver operator characteristic (ROC) curve to optimize the detection accuracy based on orthogonal test of 21 species. Antimicrobial resistance (AMR) genes were identified based on the Comprehensive Antibiotic Resistance Database (CARD) and single-nucleotide polymorphism matrix. FINDINGS: Our approach showed high sensitivity in Meta process, with 82.9%, 88.7%, and 75.0% for bacteria, fungi (except Aspergillus), and Mycobacterium tuberculosis groups, respectively. Moreover, target amplification improved the sensitivity of virus (>80.0% vs. 39.4%) and Aspergillus (81.8% vs. 42.3%) groups in Panel process compared with Meta process. Overall, NanoMP achieved 80.2% sensitivity and 98.8% specificity compared with the composite reference standard, and we were able to accurately detect AMR genes including blaKPC-2, blaOXA-23 and mecA and distinguish their parent organisms in patients with mixed infections. INTERPRETATION: We combined metagenomic and enriched Nanopore sequencing for one sample in parallel. Our NanoMP approach simultaneously covered bacteria, viruses and fungi in respiratory specimens and demonstrated good diagnostic performance in real clinical settings. FUNDING: National Key Research and Development Program of China and National Natural Science Foundation of China.


Assuntos
Sequenciamento por Nanoporos , Infecções Respiratórias , Humanos , Infecções Respiratórias/diagnóstico , Infecções Respiratórias/genética , Bactérias/genética , Metagenoma , China , Sequenciamento de Nucleotídeos em Larga Escala , Metagenômica
15.
J Fungi (Basel) ; 9(10)2023 Oct 20.
Artigo em Inglês | MEDLINE | ID: mdl-37888288

RESUMO

Postharvest diseases seriously restrict developments in the passion fruit industry. In this study, we aimed to identify the postharvest pathogen affecting passion fruit, investigate its pathogenicity, and explore relevant control methods. The pathogen was isolated from rotting passion fruit and identified using morphological characteristics, ITS sequences, and phylogenetic tree analyses. Additionally, preliminary studies were conducted to assess the biological characteristics of the pathogen and evaluate the efficacy of various treatments for disease control. The fungus on the passion fruit called B4 was identified as Diaporthe passiflorae. Optimal conditions for mycelial growth were observed at 25-30 °C and pH 5-6, with starch as the carbon source and peptone as the nitrogen source. Infection by D. passiflorae accelerated fruit decay, reduced the h° value of the peel, and increased the peel cell membrane permeability when compared to the control. Notably, treatments with appropriate concentrations of ɛ-poly-l-lysine, salicylic acid, and melatonin showed inhibitory effects on the pathogen's growth in vitro and may thus be potential postharvest treatments for controlling brown rot caused by D. passiflorae in passion fruit. The results provide a scientific basis for the development of strategies to control postharvest decay and extend the storage period of passion fruit.

16.
Chem Commun (Camb) ; 59(89): 13367-13370, 2023 Nov 07.
Artigo em Inglês | MEDLINE | ID: mdl-37874298

RESUMO

Although peripheral hetero-di-halogenation of non-fullerene acceptors (NFAs) would allow more precise optimization of molecular properties by providing the complementary advantages of two different halogens, thus enabling further improvements of organic solar cells (OSCs), hetero-di-halogenated NFAs are seldom prepared due to the challenging construction of building blocks with two adjacent hetero-halogens. Herein, three CH-series acceptors with hetero-di-halogenated central units, named CH-FC, CH-FB and CH-CB, are constructed successfully. PM6:D18:CH-FB-based OSCs afforded an attractive PCE of 19.0% due to tighter intermolecular packing at both the single-crystal and blended-film levels, more efficient charge transfer/dissociation, and superior film morphology compared to those of PM6:D18:CH-FC (PCE 18.41%) and PM6:D18:CH-CB (PCE 18.21%). Our work highlights the effectiveness of such a CH-series molecular platform in conducting hetero-di-halogenation and achieving high-performance OSCs, and will stimulate further exploration of hetero-substitution-based acceptors.

17.
Org Lett ; 25(38): 7062-7066, 2023 Sep 29.
Artigo em Inglês | MEDLINE | ID: mdl-37726866

RESUMO

A visible-light-induced radical relay strategy to access heterocycles bearing a monofluoromethylsufonyl moiety is reported, with PhI(OCOCH2F)2 as the CH2F radical precursor and DABSO as the SO2 source. A range of oxindoles, containing a CH2FSO2CH2- group at the C3 position, were synthesized from N-arylacrylamides in up to 97% yields. The protocol features catalyst-free photochemical tandem, mild reaction conditions, broad functional group compatibility, and good to excellent yields.

18.
Bioresour Technol ; 388: 129739, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-37696333

RESUMO

This study posed a novel biomimetic flocculation approach, aiming to efficiently harvest high-quality biomass of Scenedesmus quadricauda cultured with anaerobic digestate. Here, that poly(diallyldimethylammonium chloride) (PDADMAC) could serve as mimetic silicified proteins to spontaneously incorporate nanosilica onto microalgal cells, imparting diatom-like characteristics to S. quadricauda. Compared to the exponential growth phase (day 3), the highest harvesting efficiency (93.49%) was obtained at a lower dosage of PDADMAC (5 mg/g) in the stationary phase (day 6), which was attributed to changes in properties and composition of microalgal LB-EPS. On day 6, the hydrophobic functional groups in LB-EPS provided more binding sites during the flocculation process and formed a network structure of microalgal cells-flocculants-nanosilica. The resulting larger and more stable biomimetic silica shell promoted microalgal flocculation and sedimentation. Compared to conventional harvesting methods (centrifugation, polyacrylamide, alkaline flocculation), this method had the minimal negative impact on harvested biomass, with 9.95% of cell membranes damaged.


Assuntos
Microalgas , Biomassa , Floculação
19.
Nat Commun ; 14(1): 4707, 2023 Aug 05.
Artigo em Inglês | MEDLINE | ID: mdl-37543678

RESUMO

Given that bromine possesses similar properties but extra merits of easily synthesizing and polarizing comparing to homomorphic fluorine and chlorine, it is quite surprising very rare high-performance brominated small molecule acceptors have been reported. This may be caused by undesirable film morphologies stemming from relatively larger steric hindrance and excessive crystallinity of bromides. To maximize the advantages of bromides while circumventing weaknesses, three acceptors (CH20, CH21 and CH22) are constructed with stepwise brominating on central units rather than conventional end groups, thus enhancing intermolecular packing, crystallinity and dielectric constant of them without damaging the favorable intermolecular packing through end groups. Consequently, PM6:CH22-based binary organic solar cells render the highest efficiency of 19.06% for brominated acceptors, more excitingly, a record-breaking efficiency of 15.70% when further thickening active layers to ~500 nm. By exhibiting such a rare high-performance brominated acceptor, our work highlights the great potential for achieving record-breaking organic solar cells through delicately brominating.

20.
Angew Chem Int Ed Engl ; 62(42): e202308832, 2023 Oct 16.
Artigo em Inglês | MEDLINE | ID: mdl-37626468

RESUMO

In the molecular optimizations of non-fullerene acceptors (NFAs), extending the central core can tune the energy levels, reduce nonradiative energy loss, enhance the intramolecular (donor-acceptor and acceptor-acceptor) packing, facilitate the charge transport, and improve device performance. In this study, a new strategy was employed to synthesize acceptors featuring conjugation-extended electron-deficient cores. Among these, the acceptor CH-BBQ, embedded with benzobisthiadiazole, exhibited an optimal fibrillar network morphology, enhanced crystallinity, and improved charge generation/transport in blend films, leading to a power conversion efficiency of 18.94 % for CH-BBQ-based ternary organic solar cells (OSCs; 18.19 % for binary OSCs) owing to its delicate structure design and electronic configuration tuning. Both experimental and theoretical approaches were used to systematically investigate the influence of the central electron-deficient core on the properties of the acceptor and device performance. The electron-deficient core modulation paves a new pathway in the molecular engineering of NFAs, propelling relevant research forward.

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