Display omitted
•Thermal kinetics of pyrolysis and subsequent in-situ gasification of torrefied biomass pellets were studied.•Both torrefaction and densification treatments delayed the thermal ...decomposition of biomass pellets during pyrolysis.•In-situ gasification reactivity of torrefied pellet char decreased with the increase of torrefaction temperature.•Changed biomass properties by torrefaction and densification led to different pyrolysis/gasification kinetics.
Torrefaction followed by densification improves the heating value, grindability, and logistical treatment efficiency of biomass. Study of the pyrolysis and gasification of torrefied biomass pellets has great significance for the efficient conversion and utilization of biomass. In this study, the thermal behavior and reaction kinetics of pyrolysis and following in-situ CO2 gasification of torrefied corn stalk pellets were investigated in a macro-thermogravimetric analyzer. Torrefaction reduced the amounts of volatiles released during pyrolysis and the maximum pyrolysis rate of pellets decreased with the increase of torrefaction temperature. A three-pseudocomponent model applied for the pellet pyrolysis process suggested that the contribution of hemicellulose reduced as indicated by a decrease in activation energy, while lignin contributed more to the overall kinetics with the increased torrefaction temperature. The gasification of chars after the pyrolysis of torrefied pellets based on the nucleation and growth model indicated that as the torrefaction temperature increased, the gasification reactivity decreased, as implied by the evolutions of pore structures, ash compositions and graphitized crystal structures of the pellet pyrolysis chars. The higher activation energy increased the reaction resistance during the pellet gasification process. The results showed that torrefaction and densification together influenced the reaction behavior, reactivity and overall kinetics of biomass.
•The effects of minerals/binders on PM emissions from biomass combustion were studied.•Diatomite can effectively reduce the emission of PM1.•All the binders have no inhibitory effect on the PM ...emissions.•Composite additives showed positive synergistic effect in reducing PM1 emissions.
In this study, the effect of minerals and binders on the emission characteristics of particulate matter (PM) from biomass pellets combustion is investigated using a fixed bed combustor combined with a Dekati low pressure impactor (DLPI). It was found that densification reduced PM emission as the pellets hindered the release of alkali metals in comparison to the bulk biomass. The generation of PM1 was mainly due to the homogeneous condensation and heterogeneous coagulation of alkali chlorides and sulfates. Alkaline earth metals and Si played a dominant role in the formation of PM10. Diatomite in mineral additives could effectively reduce the emission of PM1, while the binders showed no inhibitory effect on the PM emission. Composite additives prepared with carboxymethyl cellulose (CMC) and diatomite showed a positive synergistic effect in reducing the emissions of PM1 with the optimum CMC/diatomite ratio of 1:4. The results showed that composite additives of minerals and binders are excellent choices for the industrial production of biomass pellets from the view of increasing pellet quality and reducing PM emission.
In this paper, we compressed the corn stalks harvested in Hubei Province into biomass-forming fuels. The physical properties of the raw materials and the physical of binders were studied. In order to ...obtain pellets with better performance, we used four different binders to make a new type pellets. We chose the best binders and best molding process by testing their mechanical properties and surface structures. Through the experiment, we obtained the best ratio of different binders to the corn stalk pellets. We also have studied the impact of different types of binders on the different properties of biomass pellets. Among the selected binders, diatomite and CMC can help us make pellets with better performance.
Abstract
As the number of electric vehicles continues to grow, the demand for charging infrastructure continues to expand, and the construction of charging facilities is significantly accelerated. ...However, after the completion of large-scale construction, problems such as low utilization, low operating profit, and extended investment payback period have emerged, which has become a bottleneck for the development of the electric vehicle industry. Based on the actual operating data of a charging station, this article analyses the operating characteristics of the charging station from the three aspects of charging power, charging time, and utilization. According to its characteristics, this article analyses the relationship with the local economic operation trend, the reasonable length of time for charging parking spaces, and the efficiency of manual maintenance. The article proposes corresponding improvement opinions for existing operational shortcomings.
Recent 15nitrogen (N) tracing studies have shown that unlabeled N2O emissions (UNEs) following 15N fertilizer application tend to be higher than those from zero-N controls, which indicates a ...potential risk for elevated N2O emissions from native soil. However, researchers do not clearly understand whether these increased UNEs are derived from a priming effect or how interactions between N in fertilizer and native soil affect various sources of N2O emissions. Here, we combined 15N tracing and 15N pool dilution in an incubation study to track gross N transformations, specific sources of N2O emissions, and N2O-production pathways following N fertilization. Four treatments, including two fertilizer N levels (0 and 120 mg N kg−1) in conjunction with two native soil N levels (0.56 and 1.25 g kg−1), were established in the study. Soil gross N mineralization (GM) increased by 33.0%–98.5% (4.59–14.97 mg N kg−1) after N fertilizer addition, which indicated a positive priming effect on soil N turnover and resulted in additional native soil N-derived N2O emissions. In addition to priming GM, the pool substitution effect after 15N addition, which was not triggered by stimulated soil N turnover, also generated substrates for the UNEs. Therefore, overlooking the pool substitution effect might overestimate native soil N-derived emissions by 104%–180%. Differentiation of the specific N2O emission sources showed that both the fertilizer N- and primed native soil N-derived N2O emissions were dominated by nitrifier-mediated processes, which were governed by ammonia-oxidizing bacteria. At a specified N fertilizer addition rate, soils with higher native N levels had greater levels of fertilizer N- and native soil N-derived N2O emissions due to the higher GM and gross nitrification rates. The study reveals that fertilizer N application triggers potential N2O emissions from native soil N by stimulating the GM and nitrifier-mediated N2O-production processes.
Display omitted
•An N pool substitution effect causes overestimation of native soil N-derived N2O.•Fertilizer N primes gross N mineralization and enhances native soil N-derived N2O.•Fertilizer N-induced N2O emissions are governed by AOB-mediated processes.•Soils with higher background N levels had greater risks for native N2O emission.
Programmed death ligand 1 (PD-L1) has conventionally been considered as a type I transmembrane protein that can interact with its receptor, programmed cell death 1 (PD-1), thus inducing T cell ...deactivation and immune escape. However, targeting the PD-1/PD-L1 axis has achieved adequate clinical responses in very few specific malignancies. Recent studies have explored the extracellularly and subcellularly located PD-L1, namely, nuclear PD-L1 (nPD-L1), cytoplasmic PD-L1 (cPD-L1), soluble PD-L1 (sPD-L1), and extracellular vesicle PD-L1 (EV PD-L1), which might shed light on the resistance to anti-PD1/PDL1 therapy. In this review, we summarize the four atypical localizations of PD-L1 with a focus on their novel functions, such as gene transcription regulation, therapeutic efficacy prediction, and resistance to various cancer therapies. Additionally, we highlight that non-cytomembrane PD-L1s are of significant cancer diagnostic value and are promising therapeutic targets to treat cancer.
Therapeutic strategies to treat pancreatic ductal adenocarcinoma (PDAC) remain unsatisfying and limited. Therefore, it is imperative to fully determine the mechanisms underlying PDAC progression. In ...the present study, we report a novel role of regulator of calcineurin 1, isoform 4 (RCAN1.4) in regulating PDAC progression. We demonstrated that RCAN1.4 expression was decreased significantly in PDAC tissues compared with that in para-cancerous tissues, and correlated with poor prognosis of patients with pancreatic cancer. In vitro, stable high expression of RCAN1.4 could suppress the metastasis and proliferation and angiogenesis of pancreatic tumor cells. In addition, interferon alpha inducible protein 27 (IFI27) was identified as having a functional role in RCAN1.4-mediated PDAC migration and invasion, while VEGFA play a vital role in RCAN1.4-mediated PDAC angiogenesis. Analysis of mice with subcutaneously/orthotopic implanted xenograft tumors and liver metastasis model confirmed that RCAN1.4 could modulate the growth, metastasis, and angiogenesis of tumors via IFI27/VEGFA in vivo. In conclusion, our results suggested that RCAN1.4 suppresses the growth, metastasis, and angiogenesis of PDAC, functioning partly via IFI27 and VEGFA. Importantly, our results provided possible diagnostic criteria and therapeutic targets for PDAC.
To improve the economics of biomass fast-pyrolysis, the aqueous phase derived from fast-pyrolysis was reformed with bio-oil to produce hydrogen by using Ni-base catalyst in this paper. The effects of ...reaction conditions such as steam-to-carbon ratio, temperature and reaction time on catalytic reforming were studied and the results indicated that the developed process was effective and feasible.
Highly desmoplastic and immunosuppressive tumor microenvironment (TME) in pancreatic ductal adenocarcinoma (PDAC) contributes to tumor progression and resistance to current therapies. Clues targeting ...the notorious stromal environment have offered hope for improving therapeutic response whereas the underlying mechanism remains unclear. Here, we find that prognostic microfibril associated protein 5 (MFAP5) is involved in activation of cancer-associated fibroblasts (CAFs). Inhibition of MFAP5
CAFs shows synergistic effect with gemcitabine-based chemotherapy and PD-L1-based immunotherapy. Mechanistically, MFAP5 deficiency in CAFs downregulates HAS2 and CXCL10 via MFAP5/RCN2/ERK/STAT1 axis, leading to angiogenesis, hyaluronic acid (HA) and collagens deposition reduction, cytotoxic T cells infiltration, and tumor cells apoptosis. Additionally, in vivo blockade of CXCL10 with AMG487 could partially reverse the pro-tumor effect from MFAP5 overexpression in CAFs and synergize with anti-PD-L1 antibody to enhance the immunotherapeutic effect. Therefore, targeting MFAP5
CAFs might be a potential adjuvant therapy to enhance the immunochemotherapy effect in PDAC via remodeling the desmoplastic and immunosuppressive microenvironment.
BackgroundsIn advanced pancreatic ductal adenocarcinoma (PDAC), immune therapy, including immune checkpoint inhibitors, has limited efficacy, encouraging the study of combination therapy.MethodsTumor ...necrosis factor receptor 2 (TNFR2) was analyzed via immunohistochemistry, immunofluorescence, western blotting, and ELISAs. The in vitro mechanism that TNFR2 regulates programmed cell death 1 ligand 1 (PD-L1) was investigated using immunofluorescence, immunohistochemistry, flow cytometry, western blotting, and chromatin immunoprecipitation (ChIP). In vivo efficacy and mechanistic studies, using C57BL/6 mice and nude mice with KPC cell-derived subcutaneous and orthotopic tumors, employed antibodies against TNFR2 and PD-L1. Survival curves were constructed for the orthotopic model and a genetically engineered PDAC model (LSL-KrasG12D/+; LSL-Trp53R172H/+; Pdx1-Cre). Mass cytometry, immunohistochemistry, and flow cytometry analyzed local and systemic alterations in the immunophenotype.ResultsTNFR2 showed high expression and is a prognostic factor in CD8+ T cell-enriched pancreatic cancer. TNFR2 promotes tumorigenesis and progression of pancreatic cancer via dual effect: suppressing cancer immunogenicity and partially accelerating tumor growth. TNFR2 positivity correlated with PD-L1, and in vitro and in vivo, it could regulate the expression of PDL1 at the transcription level via the p65 NF-κB pathway. Combining anti-TNFR2 and PD-L1 antibodies eradicated tumors, prolonged overall survival in pancreatic cancer, and induced strong antitumor immune memory and secondary prevention by reducing the infiltration of Tregs and tumor-associated macrophages and inducing CD8+ T cell activation in the PDAC microenvironment. Finally, the antitumor immune response derived from combination therapy is mainly dependent on CD8+ T cells, partially dependent on CD4+ T cells, and independent of natural killer cells.ConclusionsAnti-TNFR2 and anti-PD-L1 combination therapy eradicated tumors by inhibiting their growth, relieving tumor immunosuppression, and generating robust memory recall.
PDF
