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1.
Bioresour Technol ; 406: 131020, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-38909871

RESUMO

Hydrochar, a sustainable fertilizer rich in humic substances, is made from lignocellulose through hydrothermal conversion. However, hydrothermal humification (HTH) is challenged by low yields and limited selectivity in the resulting hydrochar. This study proved humic-like acids production can be enhanced under fast non-catalytic conditions (260 âˆ¼ 280 °C, 0 âˆ¼ 1 h). A higher yield (by 14.1 %) and selectivity (by 40.2 %) in hydrochar of humic-like acids than conventional HTH (<250 °C) were achieved. Meanwhile, decreased lignin derivatives, carbonyl and quinone groups, as well as increased sp2-C structures in the humic-like acids were observed. The synthesized humic-like acids exhibited a lower degree of aromatization and a higher molecular weight than commercial variants. Two pathways of humic-like acids formation of self-polymerization and the development of branched sidechains were hypothesized based on mass mitigation, carbon flow and aqueous phase compositions. This research contributes a novel approach to producing humic-like acids rich hydrochar for environmentally friendly fertilizer production.


Assuntos
Substâncias Húmicas , Polimerização , Zea mays , Zea mays/química , Lignina , Fertilizantes , Água/química , Temperatura
2.
Sci Total Environ ; 897: 165443, 2023 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-37442473

RESUMO

Investigation on the distribution and mechanism of co-pyrolysis products is vital to the directional control and high-value utilization of agriculture solid wastes. Co-pyrolysis, devolatilization, kinetics characteristics, and evolution paths of corn stalk (CS) and low-density-polyethylene (LDPE) were investigated via thermogravimetric experiments. The co-pyrolysis behaviors could be separated into two stages: firstly, the degradation of CS (150- 400 °C); secondly, the degradation of CS (400- 550 °C). The devolatilization index (DI) increased with the addition of LDPE. Furthermore, a combination of devolatilization chemical analysis with product analysis to analyze the intrinsic mechanism during co-pyrolysis. The results indicated that the yield of alkanes and olefin in gas products increased with the addition of LDPE. Additionally, LDPE pyrolysis maybe abstract hydrogen from CS pyrolysis and evolved into hydrogen, methane, and ethylene. Further, the co-pyrolysis kinetic parameters were computed by using model-free isoconversion methods, which showed promotion of CS pyrolysis and the reduced activation energy. All the activation energy were declined, which indicated a "bidirectional positive effect" during co-pyrolysis. The mean activation energy of P-cellulose (P-CE), P-hemicellulose (P-HM), P-lignin (P-LG), and LDPE decreased by 23.49 %, 12.89 %, 15.36 %, and 27.82 %, respectively. This study further proves the hydrogen donor transfer pathway in the co-pyrolysis process of CS and LDPE, providing theoretical support for the resource utilization of agricultural solid waste.


Assuntos
Polietileno , Pirólise , Biomassa , Cinética , Celulose , Resíduos Sólidos
3.
Sci Total Environ ; 840: 156697, 2022 Sep 20.
Artigo em Inglês | MEDLINE | ID: mdl-35710015

RESUMO

Microplastics have been widely detected in natural and engineered water systems and removing microplastics from various water matrices has become a major challenge. Mini-hydrocyclones (MHCs) have been previously applied to separate mediums of different phases. Given MHCs' capability of separating fine particles from liquid phase, three MHCs were designed and fabricated in stainless steel with 3D printing. Microplastics of densities that were both lower (<1 g·cm-3) and higher (>1 g·cm-3) than water's density were used to test the separation efficiency in ultra-purified water. The separation test was performed on single-stage MHC as well as MHCs in series in a closed hydraulic circuit. A range of important operational parameters, including split ratio, feed pressure, feed flow rate, and solid concentration, were evaluated to optimize the separation efficiency. The single-stage MHC experiment revealed that >80 % microplastics >20 µm can be effectively removed at the concentration tested, and the separation efficiency peaked at the split ratio of 35 %. MHCs in series demonstrated their ability to further enhance the separation efficiency of the ones with the same density, as well as separate microplastics of different densities. Mini-hydrocyclones' were also used to separate microplastics in synthetic stormwater, and separation efficiency reached 84 % and 98.1 % for low-density polyethylene (LDPE) and polyamide (PA). The results indicated the MHCs' potential for large-scale application in microplastic separation for industrial and municipal wastewater.


Assuntos
Microplásticos , Poluentes Químicos da Água , Monitoramento Ambiental , Plásticos , Aço Inoxidável , Águas Residuárias , Água , Poluentes Químicos da Água/análise
4.
Bioresour Technol ; 348: 126778, 2022 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-35104655

RESUMO

Dry-wet combined anaerobic digestion is a novel approach for treating lignocellulosic waste by increasing the organic load of reactor while accelerating the conversion of organic acids. Here, we investigated the effect of regulated substrate ratios and initial pH in the dry acidogenesis stage on the bioconversion efficiency of dry-wet combined anaerobic digestion. Our data revealed microbial interactions and further identified key microbes based on microbial co-occurrence network analysis. On day three of acidification, the kinetic hydrolysis rate and acidification yield reached 1.66 and 60.07%, respectively; this was attributed to enhancement of the synergistic effect between Clostridiales and Methanosaeta, which increased the proportion of corn straw in the substrate or lowered the initial spray slurry pH to 5.5-6.5. With increased acidification capacity, acetoclastic methanogens were enriched in the wet methanogenesis stage; the syntrophic effect of Syntrophomonadales, Syntrophobacterales and Methanospirillum, meanwhile, was enhanced, leading to an overall improvement in biogas production.


Assuntos
Biocombustíveis , Reatores Biológicos , Anaerobiose , Lignina , Metano
5.
Adv Sci (Weinh) ; 9(29): e2202039, 2022 10.
Artigo em Inglês | MEDLINE | ID: mdl-35988145

RESUMO

Recent evidence has indicated that overexpression of the epigenetic reader bromodomain-containing protein 4 (BRD4) contributes to a poor prognosis of lung cancers, and the suppression of its expression promotes cell apoptosis and leads to tumor shrinkage. Proteolysis targeting chimera (PROTAC) has recently emerged as a promising therapeutic strategy with the capability to precisely degrade targeted proteins. Herein, a novel style of versatile nano-PROTAC (CREATE (CRV-LLC membrane/DS-PLGA/dBET6)) is developed, which is constructed by using a pH/GSH (glutathione)-responsive polymer (disulfide bond-linked poly(lactic-co-glycolic acid), DS-PLGA) to load BRD4-targeted PROTAC (dBET6), followed by the camouflage with engineered lung cancer cell membranes with dual targeting capability. Notably, CREATE remarkably confers simultaneous targeting ability to lung cancer cells and tumor-associated macrophages (TAMs). The pH/GSH-responsive design improves the release of dBET6 payload from nanoparticles to induce pronounced apoptosis of both cells, which synergistically inhibits tumor growth in both subcutaneous and orthotopic tumor-bearing mouse model. Furthermore, the efficient tumor inhibition is due to the direct elimination of lung cancer cells and TAMs, which remodels the tumor microenvironment. Taken together, the results elucidate the construction of a versatile nano-PROTAC enables to eliminate both lung cancer cells and TAMs, which opens a new avenue for efficient lung cancer therapy via PROTAC.


Assuntos
Neoplasias Pulmonares , Fatores de Transcrição , Animais , Camundongos , Dissulfetos/metabolismo , Epigênese Genética , Glutationa/metabolismo , Neoplasias Pulmonares/genética , Neoplasias Pulmonares/terapia , Proteínas Nucleares/genética , Proteínas Nucleares/metabolismo , Copolímero de Ácido Poliláctico e Ácido Poliglicólico/metabolismo , Polímeros , Proteólise , Fatores de Transcrição/genética , Fatores de Transcrição/metabolismo , Microambiente Tumoral
6.
Bioresour Technol ; 342: 125914, 2021 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-34530252

RESUMO

The production of hydrochar and biocrude from hydrothermal treatment of lignocellulosic biomass is getting increasing attention, but the quality of hydrochar and biocrude need further improvement before utilization. Many attempts have been carried out on the hydrochar activation and biocrude upgrading. However, different methods play different roles on the property of hydrochar and biocrude, this topic received scant attention in recent review papers. Therefore, the influence of different activation methods on hydrochar property, and the potential application of hydrochar were summarized in this study. Meanwhile, the research progress on biocrude upgrading is reported. Besides, the techno-economic analysis of hydrochar and biocrude from hydrothermal treatment of lignocellulosic biomass are also discussed. Finally, the research needs and future directions on hydrochar activation and biocrude upgrading were proposed. This paper could provide insights for further studies on the utilization of hydrochar and biocrude.


Assuntos
Carbono , Biomassa , Lignina , Temperatura
7.
Bioresour Technol ; 333: 125204, 2021 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-33932811

RESUMO

In this study, Anaerobic Digestion Model No. 1 (ADM1) were modified to simulate anaerobic digestion (AD) process of microcrystalline cellulose (MCC) and five lignocellulosic substrates, with the goal of predicting the hydrolysis rates of holocellulose fractions in environments with and without lignin inhibition. After model verification, the hydrolysis rate constant of MCC, i.e., the hydrolyzability of cellulose without lignin inhibition, was 3.227 d-1, while those of the holocellulose fractions of five lignocellulosic substrates (I_khyd) were in the range of 1.270 d-1 to 3.364 d-1 (average of 2.242 d-1), which demonstrated remarkable suppression of holocellulose hydrolysis by lignin. Lignin inhibition index (LII) was proposed as an indicator to intuitively quantify and characterize the lignin inhibitory strength in a specific substrate. A series of factors with the potential to affect the LII were analyzed sequentially. This study provides an advanced understanding of the participation and behavior of lignin in the AD process.


Assuntos
Lignina , Anaerobiose , Hidrólise , Lignina/metabolismo
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