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1.
Environ Sci Technol ; 58(18): 7826-7837, 2024 May 07.
Article in English | MEDLINE | ID: mdl-38653213

ABSTRACT

The interaction effects between the main components (proteins (P), carbohydrates (C), and lipids (L)) of protein-rich biomass during microwave-assisted pyrolysis were investigated in depth with an exploration of individual pyrolysis and copyrolysis (PC, PL, and CL) of model compounds. The average heating rate of P was higher than those of C and L, and the interactions in all copyrolysis groups reduced the max instant heating rate. The synergistic extent (S) of PC and PL for bio-oil yield was 16.78 and 18.24%, respectively, indicating that the interactions promoted the production of bio-oil. Besides, all of the copyrolysis groups exhibited a synergistic effect on biochar production (S = 19.43-28.24%), while inhibiting the gas generation, with S ranging from -20.17 to -6.09%. Regarding the gaseous products, apart from H2, P, C, and L primarily generated CO2, CO, and CH4, respectively. Regarding bio-oil composition, the interactions occurring within PC, PL, and CL exhibited a significantly synergistic effect (S = 47.81-412.96%) on the formation of N-heterocyclics/amides, amides/nitriles, and acids/esters, respectively. Finally, the favorable applicability of the proposed interaction effects was verified with microalgae. This study offers valuable insights for understanding the microwave-assisted pyrolysis of protein-rich biomass, laying the groundwork for further research and process optimization.


Subject(s)
Biomass , Microwaves , Pyrolysis , Proteins/chemistry , Lipids/chemistry , Charcoal/chemistry , Carbohydrates/chemistry , Biofuels
2.
Article in English | MEDLINE | ID: mdl-38015404

ABSTRACT

The ever-increasing concern for energy shortages and greenhouse effect has triggered the development of sustainable green technologies. Microalgae have received more attention due to the characteristics of biofuel production and CO2 fixation. From the perspective of autotrophic growth, the optimization of light quality has the potential to promote biomass production and bio-component accumulation in microalgae at low cost. In this study, bibliometric analysis was used to describe the basic features, identify the hotspots, and predict future trends of the research related to the light quality on microalgae cultivation. In addition, a mini-review referring to regulation methods of light quality was provided to optimize the framework of research. Results demonstrated that China has the greatest interest in this area. The destination of most research was to obtain biofuels and high-value-added products. Both blue and red lights were identified as the crucial spectrums for microalgae cultivation. However, sunlight is the most affordable light resource, which could not be fully utilized by microalgae through the photosynthetic process. Hence, some regulation approaches (e.g., dyes, plasmonic scattering, and carbon-based quantum dots) are proposed to increase the proportion of beneficial spectrum for enhancement of photosynthetic efficiency. In summary, this review introduces state-of-the-art research and provides theoretical guidance for light quality optimization in microalgae cultivation to obtain more benefits.

3.
Front Environ Sci Eng ; 17(7): 83, 2023.
Article in English | MEDLINE | ID: mdl-36776490

ABSTRACT

Blackwater (BW), consisting of feces, urine, flushing water and toilet paper, makes up an important portion of domestic wastewater. The improper disposal of BW may lead to environmental pollution and disease transmission, threatening the sustainable development of the world. Rich in nutrients and organic matter, BW could be treated for resource recovery and reuse through various approaches. Aimed at providing guidance for the future development of BW treatment and resource recovery, this paper presented a literature review of BWs produced in different countries and types of toilets, including their physiochemical characteristics, and current treatment and resource recovery strategies. The degradation and utilization of carbon (C), nitrogen (N) and phosphorus (P) within BW are underlined. The performance of different systems was classified and summarized. Among all the treating systems, biological and ecological systems have been long and widely applied for BW treatment, showing their universality and operability in nutrients and energy recovery, but they are either slow or ineffective in removal of some refractory pollutants. Novel processes, especially advanced oxidation processes (AOPs), are becoming increasingly extensively studied in BW treatment because of their high efficiency, especially for the removal of micropollutants and pathogens. This review could serve as an instructive guidance for the design and optimization of BW treatment technologies, aiming to help in the fulfilment of sustainable human excreta management.

4.
Clin Exp Metastasis ; 40(2): 149-160, 2023 04.
Article in English | MEDLINE | ID: mdl-36807216

ABSTRACT

BACKGROUND: Sufentanil combined with parecoxib sodium is a commonly used postoperative medication for cancer patients. However, the effects of this combination therapy on human epidermal growth factor receptor-2 (HER2)-positive breast cancer cells have still remained elusive. This study aimed to investigate the effects and potential mechanisms of sufentanil combined with parecoxib sodium on HER2-positive breast cancer cells. METHODS: The cell counting kit-8 (CCK-8), colony formation, flow cytometry, scratch, transwell invasion, and angiogenesis assays were used to assess the proliferation, cell cycling, migration, invasion, and angiogenesis of HER2-positive breast cancer BT474 cells. Western blot assay was employed for detecting the expression levels of proteins involved in the cell cycle, migration, invasion, angiogenesis, and epithelial-mesenchymal transition (EMT). The in vivo effects of tumor growth and metastasis were examined by establishing an orthotopic transplantation mouse model of HER2-positive breast cancer (MMTV-PyMT). RESULTS: Functional assays indicated that sufentanil combined with parecoxib sodium induced blockade of HER2-positive breast cancer BT474 cells in the G1 phase of the cell cycle and inhibited cell proliferation, migration, angiogenesis, and invasion in vitro. Western blot assay revealed that sufentanil combined with parecoxib sodium downregulated the expression levels of cyclin D1, matrix metalloproteinase-9 (MMP-9), cyclooxygenase-2 (COX-2), vascular endothelial growth factor A (VEGFA), and EMT-related proteins (N-cadherin, Vimentin, and Snail), while up-regulated the expression level of E-cadherin in BT474 cells. In addition, it was found that sufentanil combined with parecoxib sodium inhibited tumor growth and metastasis in the orthotopic transplantation mouse model of HER2-positive breast cancer. CONCLUSION: Sufentanil combined with parecoxib sodium inhibited HER2-positive breast cancer progression, including cell proliferation, cell cycle, migration, invasion, and angiogenesis, and regulated EMT.


Subject(s)
Breast Neoplasms , Animals , Female , Humans , Mice , Breast Neoplasms/pathology , Cell Line, Tumor , Cell Movement , Cell Proliferation , Epithelial-Mesenchymal Transition , Sufentanil/pharmacology , Vascular Endothelial Growth Factor A
5.
Sci Total Environ ; 854: 158722, 2023 Jan 01.
Article in English | MEDLINE | ID: mdl-36108851

ABSTRACT

Graphene oxide quantum dots (GOQDs) can convert the ultraviolet (200- 380 nm) into available wavelength (400- 700 nm) for microalgae cultivation. However, it has not been applied in large-scale microalgae culture due to its high cost and difficulties in recovery. This study proposed a new strategy for the sustainable use of GOQDs, namely, GOQDs solution was added to the outer sandwich of the reactor. Herein, the effects of direct and indirect exposure of different GOQDs concentrations (0, 100, and 1000 mg/L) on the microalgae culture were compared. When microalgae were directly exposed to the GOQDs, 100 mg/L of GOQDs increased the biomass production of microalgae by 24.0 %, while 1000 mg/L of GOQDs decreased biomass production by 31 %. High concentration of GOQDs (direct exposure) could cause extra oxidative stress in the microalgae cells and result in a significant reduction of pigment content. When microalgae were indirectly exposed to the GOQDs, the increased concentration of GOQDs enhanced the growth of microalgae. Compared to the blank group, 1000 mg/L of GOQDs increased the microalgae biomass production and bioenergy by 14.1 % and 40.17 %, respectively. The indirect exposure of GOQDs can effectively avoid photo-oxidation and organelle damage to the microalgae cells. Overall, the indirect exposure of GOQDs is a sustainable way for effectively promoting microalgae growth and reducing the application cost.


Subject(s)
Chlorella , Graphite , Microalgae , Quantum Dots , Quantum Dots/toxicity , Graphite/toxicity , Biomass
6.
Environ Technol ; 44(1): 68-81, 2023 Jan.
Article in English | MEDLINE | ID: mdl-34330190

ABSTRACT

Fe3O4 nanoparticles (NPs) have potential effects on the anaerobic digestion of excess sludge. The effects of different concentrations of Fe3O4 NPs (0, 100, 200, 400 and 600 mg/L) on enzymes and microorganisms in anaerobic digestion were studied to explore the mechanism of the effect of Fe3O4 NPs on anaerobic digestion. The results showed that 100, 200 and 400 mg/L Fe3O4 NPs could promote anaerobic digestion, and 200 mg/L Fe3O4 NPs had the most obvious promoting effect. The activities of protease, cellulase, dehydrogenase, acetic kinase and coenzyme F420 in the 200 mg/L Fe3O4 NPs group reached 120 U/mg VS, 71.75 U/g VS, 135 U/mL, 94 mol/L, 1.37 umol/g VSS, respectively, which were 3.8, 1.5, 1.2, 1.2 and 1.6 times of the blank group, respectively. However, when the concentration of Fe3O4 NPs reached 600 mg/L, the activities of cellulase, dehydrogenase and acetic kinase were lower than those of the blank group, and anaerobic digestion was inhibited. The above conclusions can also be confirmed by high-throughput sequencing. The abundance of longilinea and ornatilina in the 200 mg/L Fe3O4 NPs group was 8.8% and 4.1% respectively, and methanthrix abundance was 69%, which was more conducive to decomposition acetic acid into CH4.Highlights To explore the effects of Fe3O4 NPS on enzyme activity and microorganisms.200mg/L Fe3O4 NPs could significantly promote the activity of enzyme.200mg/L Fe3O4 NPs could promote the diversity of bacterial and archaeal communities.600mg/L Fe3O4 NPs could inhibit some enzyme activities and microbial community diversity.


Subject(s)
Cellulases , Microbiota , Nanoparticles , Sewage/microbiology , Anaerobiosis , Oxidoreductases , Bioreactors/microbiology , Methane
7.
Environ Res ; 209: 112860, 2022 06.
Article in English | MEDLINE | ID: mdl-35123965

ABSTRACT

As the global economy develops and the population increases, greenhouse gas emissions and wastewater discharge have become inevitable global problems. Conventional wastewater treatment processes produce direct or indirect greenhouse gas, which can intensify global warming. Microalgae-based wastewater treatment technology can not only purify wastewater and use the nutrients in wastewater to produce microalgae biomass, but it can also absorb CO2 in the atmosphere or flue gas through photosynthesis, which demonstrates great potential as a sustainable and economical wastewater treatment technology. This review highlights the multifaceted roles of microalgae in different types of wastewater treatment processes in terms of the extent of their bioremediation function and microalgae biomass production. In addition, various newly developed microalgae cultivation systems, especially biofilm cultivation systems, were further characterized systematically. The performance of different microalgae cultivation systems was studied and summarized. Current research on the technical approaches for the modification of the CO2 capture by microalgae and the maximization of CO2 transfer and conversion efficiency were also reviewed. This review serves as a useful and informative reference for the application of wastewater treatment and CO2 capture by microalgae, aiming to provide a reference for the realization of carbon neutrality in wastewater treatment systems.


Subject(s)
Microalgae , Biomass , Carbon , Carbon Dioxide , Wastewater/analysis
8.
Environ Technol ; 43(23): 3538-3551, 2022 Sep.
Article in English | MEDLINE | ID: mdl-33944701

ABSTRACT

A large amount of waste activated sludge (WAS) harms the ecological environment, and anaerobic digestion (AD) is an effective method for WAS treatment. In this study, activated carbon (AC)/ nano zero-valent iron (NZVI) was synthesized by a liquid-phase reduction method, and was used to boost methane production. The associated mechanisms and effects of additives on AD during the addition and removal stage were investigated systematically. Compared to the blank group, the cumulative methane production was increased by 14.3%, 26.3% and 34.1% in the groups of AC, NZVI and AC/NZVI, respectively. The addition of AC/NZVI significantly increased the concentration of VFAs and promoted the hydrolysis and acidification of WAS. After the AD of the additives addition stage was finished, the additives were removed and the sludge was replenished in all groups, the methanogenesis performance of the experimental groups was significantly inhibited. The cumulative methane production in the AC and AC/NZVI groups was 21.7% and 13.5% lower than the blank group, respectively. The experimental results have a good correlation with curve fitting by the modified Gompertz model. The modified Gompertz model found that AC, NZVI and AC/NZVI increased the methanogenic potential and maximum methane production rate of WAS, but also prolonged the lag-phase time. AC/NZVI might play a role in coupling effects. It could not only maintain the original characteristics of NZVI and increase its stability, but also develop the advantages of AC promoting direct interspecies electron transfer. Microbial community analysis indicated that the abundance of hydrogenotrophic methanogens was enriched by AC/NZVI.


Subject(s)
Charcoal , Sewage , Anaerobiosis , Iron , Methane
9.
Environ Technol ; 42(10): 1542-1551, 2021 Apr.
Article in English | MEDLINE | ID: mdl-31560610

ABSTRACT

With their wide application, some nanomaterials entering into the environment and made effects in many ways. Different concentrations of Fe3O4 nanoparticles (NPs) were added (0, 100, 200, 400 and 600 mg/L) in this study, the changes of substance in three stages of anaerobic digestion (AD) were explored, the optimal dosage of Fe3O4 NPs was finally found. The results showed that the 200 mg/L Fe3O4 NPs could better promote the decomposition of organic matter than the other groups, the protein and polysaccharide degradation rate reached to 99.75% and 83.14%, respectively. In the acidogenesis stage, the acetic acid concentration reached up to 692.88 mg/L, increased by 31.8% compared with the control group. Fe3O4 NPs had also been proved to increase VFAs, finally made the methane content reach to 92.22%. The variation of coenzyme F420 had also been described in this research, the highest value was 1.83 Umol/g VS. These results showed that the different concentrations of Fe3O4 NPs had different effects on anaerobic digestion.


Subject(s)
Nanoparticles , Sewage , Anaerobiosis , Bioreactors , Methane
10.
Environ Technol ; 41(24): 3199-3209, 2020 Oct.
Article in English | MEDLINE | ID: mdl-30955456

ABSTRACT

Nanoscale zero-valent iron (NZVI), which is increasingly used for environmental remediation, has potential positive impact on Anaerobic Digestion (AD). In this study, the changes of three phases in the AD of sludge have been analysed. The addition of NZVI (1000 mg/L) in the experimental reactors resulted in an enhanced operational performance, i.e. TCOD, SCOD removal and biogas production increased by 23.13%, 12.60% and 29.55% respectively. The addition of NZVI also kept pH at an appropriate level, enhanced the use of volatile fatty acids (VFAs) and the activity of the characteristic enzyme relative to the blank group. The Scanning Electron Microscope (SEM) and Energy Dispersive Spectrometer (EDS) were employed to investigate the changes in surface morphology and elements of the sludge. The infrared spectra analysis showed that NZVI promoted AD of sludge. The results from the three-phase change reflected that the addition of NZVI not only promoted AD of sludge but also improved the resource utilization of sludge.


Subject(s)
Iron , Sewage , Anaerobiosis , Biofuels/analysis , Fatty Acids, Volatile
11.
Sci Total Environ ; 703: 135532, 2020 Feb 10.
Article in English | MEDLINE | ID: mdl-31759718

ABSTRACT

This study evaluated the effects of nano zero-valent iron (NZVI, 50 nm) on anaerobic digestion of high solids sludge (10 ± 0.5%). Compared to the blank group without NZVI, the group with NZVI at all levels (10, 20 and 30 mM) played a driving role in methane production. The maximal methane production was increased by 37.5% in the group of 30 mM NZVI. The dynamic changes of hydrogen content and VFAs showed that rapid hydrogen evolutional corrosion of NZVI made lower hydrogen partial pressure in the later stage, which was more conducive to conversion of propionic acid. The microscopic analysis indicated that NZVI could flocculate and adsorb on the extracellular polymeric substances (EPS) around the anaerobic microorganisms, protecting most active microbial cell membrane from contact damage. On the other hand, some decaying microbial cells membrane could be destroyed by NZVI and intracellular substances would be released due to the reduction of EPS.


Subject(s)
Bioreactors , Methane/metabolism , Anaerobiosis , Fatty Acids, Volatile , Hydrogen , Iron/chemistry , Sewage
12.
RSC Adv ; 9(33): 19104-19113, 2019 Jun 14.
Article in English | MEDLINE | ID: mdl-35558094

ABSTRACT

This study is an assessment of hydrothermal pre-treatment (HTP) of different solid-liquid ratio (SLR) sewage sludge for enhancement of biogas production by anaerobic digestion. Anaerobic digestion efficacy was investigated by biochemical methane potential (BMP) tests and kinetic analyses. The results indicated that the solid-liquid ratio (SLR) of sludge could influence the COD solubilization and the concentration of volatile fatty acids (VFAs) after HTP. BMP tests revealed that HTP could improve the final methane yield. For the different solid-liquid ratios (5%, 8%, 10%, 12% and 15%) of sludge after HTP, the methane contents were found to be 64%, 66%, 62%, 61% and 60%, respectively. The optimum solid-liquid ratio was found to be 8%, and its cumulative biogas yield was 425.57 N ml g-1 VS. The modified Gompertz model and Logistic model were used for kinetic study of biogas production. Kinetic study results showed that the experimental data could be fitted with the two models and the modified Gompertz model was better fitted with the experimental data than the Logistic model. These findings proved that choosing an appropriate solid-liquid ratio for HTP could effectively improve the anaerobic digestion process of sewage sludge.

13.
Nanotechnology ; 18(3): 035701, 2007 Jan 24.
Article in English | MEDLINE | ID: mdl-19636132

ABSTRACT

In this study, hydrophilic high-luminescent magnetic nanocomposites (LMNCs) composed of both fluorescent clusters (quantum dots, QDs) and magnetic nanoparticles were synthesized. The nanocomposites exhibited high luminescence and were easily separated in an external magnetic field. The LMNCs were capped with streptavidin (SA), and the SA on the surface of LMNC-SA composites was confirmed to be bioactive by competitive inhibition analytic methods. The fabricated LMNC-SA composites have potential application in biolabelling, bioseparation, immunoassay and pathogenic diagnosis.

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