This study aimed to investigate the mechanism of nitrogen doping,migration,and conversion during ammonia torrefaction and also explore the evolution law of the chemical structure of cellulose.The results showed that t...This study aimed to investigate the mechanism of nitrogen doping,migration,and conversion during ammonia torrefaction and also explore the evolution law of the chemical structure of cellulose.The results showed that the ammonia torrefaction pretreatment could significantly optimize the distribution of nitrogen and oxygen elements in cellulose.The carbon skeleton first captured the active nitrogenous radicals to form-NHn-N,and pyridine-N and pyrrole-N originated from the conversion of-NHn-N.The existence of C=O played a major role in the immobilization of nitrogen.The nitrogen in bio-oil exists mainly in the form of five-and six-membered heterocycles.The correlation analysis showed that the main precursors for the formation of nitrogenous heterocyclic compounds were five-membered Oheterocyclic compounds.Finally,the product distribution characteristics in the torrefaction-pyrolysis systems were summarized,and the nitrogen doping and conversion mechanisms were proposed.This study expanded the boundaries of cellulose pretreatment and the production of high-value chemicals.展开更多
To the Editor:Malignant pleural effusion(MPE)is a collection of a large amount of exudativeuid in the pleural cavity that mainly originates from pleural metastases in patients with malignant tumors.The formation of MP...To the Editor:Malignant pleural effusion(MPE)is a collection of a large amount of exudativeuid in the pleural cavity that mainly originates from pleural metastases in patients with malignant tumors.The formation of MPE is related to angiogenesis,increased vascular permeability,lymphatic obstruction,immune reactions,and the tumor metastasis microenvironment,but molecular-based diagnostic and next-generation therapeutic strategies for MPE are still lacking.Exosomes are vesicles with a double-layered lipid membrane structure that are widely distributed in bodyuids and can be produced by almost all cells.Increased evidence has shown that exosomes are related to the development of MPE and are correlated with the efcacy of and response to targeted therapy or immunotherapy.Although exosomes are one of the main components of MPE,the source and functional role of exosomes in MPE are still unclear.展开更多
基金sponsored by the National Natural Science Foundation of China(52176193)the National Key Research and Development Program of China(2019YFD1100602)+1 种基金the Shandong Provincial Natural Science Foundation,China(ZR2020ME184)the SDUT & Zhangdian City Integration Development Project(2021JSCG0013)。
文摘This study aimed to investigate the mechanism of nitrogen doping,migration,and conversion during ammonia torrefaction and also explore the evolution law of the chemical structure of cellulose.The results showed that the ammonia torrefaction pretreatment could significantly optimize the distribution of nitrogen and oxygen elements in cellulose.The carbon skeleton first captured the active nitrogenous radicals to form-NHn-N,and pyridine-N and pyrrole-N originated from the conversion of-NHn-N.The existence of C=O played a major role in the immobilization of nitrogen.The nitrogen in bio-oil exists mainly in the form of five-and six-membered heterocycles.The correlation analysis showed that the main precursors for the formation of nitrogenous heterocyclic compounds were five-membered Oheterocyclic compounds.Finally,the product distribution characteristics in the torrefaction-pyrolysis systems were summarized,and the nitrogen doping and conversion mechanisms were proposed.This study expanded the boundaries of cellulose pretreatment and the production of high-value chemicals.
基金Key R&D Plan of Jiangxi Province(No.2021BBG71006)Zhejiang Provincial Basic Public Welfare Research Project(No.GF19H160028)Key project of Science and Technology Innovation of Health Commission of Jiangxi Province(Nos.2023ZD005 and 2024ZD008)
文摘To the Editor:Malignant pleural effusion(MPE)is a collection of a large amount of exudativeuid in the pleural cavity that mainly originates from pleural metastases in patients with malignant tumors.The formation of MPE is related to angiogenesis,increased vascular permeability,lymphatic obstruction,immune reactions,and the tumor metastasis microenvironment,but molecular-based diagnostic and next-generation therapeutic strategies for MPE are still lacking.Exosomes are vesicles with a double-layered lipid membrane structure that are widely distributed in bodyuids and can be produced by almost all cells.Increased evidence has shown that exosomes are related to the development of MPE and are correlated with the efcacy of and response to targeted therapy or immunotherapy.Although exosomes are one of the main components of MPE,the source and functional role of exosomes in MPE are still unclear.
