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1.
Int J Biol Macromol ; 264(Pt 1): 130390, 2024 Apr.
Article in English | MEDLINE | ID: mdl-38403228

ABSTRACT

The process of lignin extraction often involves intricate chemical transformations, influencing its potential for high-value utilization. By investigating the process of lignin derivatives extraction from hemp fibers using supercritical CO2, ethanol, and water, we identified the relationship between the chemical structure of lignin derivatives and temperature. This discovery contributes to controlling the chemical structure of lignin derivatives through temperature modulation. We observed that lignin derivatives extracted within the temperature range of 100-120 °C exhibited the lowest average molecular weight and polydispersity index, presenting a disordered microstructure with the highest hydroxyl content. Lignin derivatives extracted between 140 and 160 °C showed an increase in average molecular weight and polydispersity index, decreased hydroxyl content, and a gradual transformation of microstructure into spherical particles. At 180 °C, the average molecular weight and polydispersity index of lignin derivatives decreased, the microstructure of lignin derivatives showed fewer spherical particles, while its hydroxyl content exhibited a partial recovery. Chemical analysis revealed a lower degree of condensation in lignin derivatives at 100-120 °C. Between 120 and 160 °C, the degree of condensation increased. At 180 °C, extensive degradation occurred in lignin derivatives. This research advances innovative techniques for lignin derivative separation, contributing to their utilization in higher-value applications.


Subject(s)
Cannabis , Lignin , Lignin/chemistry , Ethanol/chemistry , Water/chemistry , Carbon Dioxide , Temperature
2.
PLoS One ; 17(1): e0262261, 2022.
Article in English | MEDLINE | ID: mdl-35085274

ABSTRACT

BACKGROUND: As the world's largest coal producer, China was accounted for about 46% of global coal production. Among present coal mining risks, methane gas (called gas in this paper) explosion or ignition in an underground mine remains ever-present. Although many techniques have been used, gas accidents associated with the complex elements of underground gassy mines need more robust monitoring or warning systems to identify risks. This paper aimed to determine which single method between the PCA and Entropy methods better establishes a responsive weighted indexing measurement to improve coal mining safety. METHODS: Qualitative and quantitative mixed research methodologies were adopted for this research, including analysis of two case studies, correlation analysis, and comparative analysis. The literature reviewed the most-used multi-criteria decision making (MCDM) methods, including subjective methods and objective methods. The advantages and disadvantages of each MCDM method were briefly discussed. One more round literature review was conducted to search publications between 2017 and 2019 in CNKI. Followed two case studies, correlation analysis and comparative analysis were then conducted. Research ethics was approved by the Shanxi Coking Coal Group Research Committee. RESULTS: The literature searched a total of 25,831publications and found that the PCA method was the predominant method adopted, and the Entropy method was the second most widely adopted method. Two weighting methods were compared using two case studies. For the comparative analysis of Case Study 1, the PCA method appeared to be more responsive than the Entropy. For Case Study 2, the Entropy method is more responsive than the PCA. As a result, both methods were adopted for different cases in the case study mine and finally deployed for user acceptance testing on 5 November 2020. CONCLUSIONS: The findings and suggestions were provided as further scopes for further research. This research indicated that no single method could be adopted as the better option for establishing indexing measurement in all cases. The practical implication suggests that comparative analysis should always be conducted on each case and determine the appropriate weighting method to the relevant case. This research recommended that the PCA method was a dimension reduction technique that could be handy for identifying the critical variables or factors and effectively used in hazard, risk, and emergency assessment. The PCA method might also be well-applied for developing predicting and forecasting systems as it was sensitive to outliers. The Entropy method might be suitable for all the cases requiring the MCDM. There is also a need to conduct further research to probe the causal reasons why the PCA and Entropy methods were applied to each case and not the other way round. This research found that the Entropy method provides higher accuracy than the PCA method. This research also found that the Entropy method demonstrated to assess the weights of the higher dimension dataset was higher sensitivity than the lower dimensions. Finally, the comprehensive analysis indicates a need to explore a more responsive method for establishing a weighted indexing measurement for warning applications in hazard, risk, and emergency assessments.


Subject(s)
Coal Mining/methods , Coal/adverse effects , Principal Component Analysis/methods , Safety Management/methods , Accidents, Occupational/prevention & control , China , Entropy , Evaluation Studies as Topic
3.
J Pharm Sci ; 108(3): 1284-1295, 2019 03.
Article in English | MEDLINE | ID: mdl-30395829

ABSTRACT

Chemotherapy has been the standard for cancer therapy, but the nonspecific cytotoxicity of chemotherapeutic agents and drug resistance of tumor cells has limited its efficacy. However, multidrug combination therapy and targeting therapy have resulted in enhanced anticancer effects and have become increasingly important strategies in clinical applications. In this study, a biotin-/lactobionic acid-modified poly(ethylene glycol)-poly(lactic-co-glycolic acid)-poly(ethylene glycol) (BLPP) copolymer was synthesized, and curcumin- and 5-fluorouracil-loaded nanoparticles (BLPPNPs/C + F) were prepared to enhance the treatment of hepatocellular carcinoma. Blank BLPPNPs were shown to have great biocompatibility via both in vitro and in vivo studies. Good targeting of tumor cells of BLPPNPs was confirmed by flow cytometry, fluorescence microscopy, and biodistribution. The synergistic anticancer effects of BLPPNPs/C + F were demonstrated by cytotoxicity and animal studies, while western blotting was used to further verify the synergistic effect of curcumin and 5-fluorouracil. The dual-targeting and drug-loaded codelivery nanosystem demonstrated higher cellular uptake and stronger cytotoxicity for tumor cells. Therefore, these dual-targeting NPs are a promising codelivery carrier that could be made available for cellular targeting of anticancer drugs to achieve better intracellular delivery and synergistic anticancer efficacy.


Subject(s)
Antineoplastic Combined Chemotherapy Protocols/administration & dosage , Carcinoma, Hepatocellular/drug therapy , Drug Carriers/chemistry , Liver Neoplasms/drug therapy , Nanoparticles/chemistry , Animals , Antineoplastic Combined Chemotherapy Protocols/pharmacokinetics , Biotin/chemistry , Carcinoma, Hepatocellular/pathology , Curcumin/administration & dosage , Curcumin/pharmacokinetics , Disaccharides/chemistry , Drug Liberation , Drug Synergism , Fluorouracil/administration & dosage , Fluorouracil/pharmacokinetics , Hep G2 Cells , Humans , Liver Neoplasms/pathology , Mice , Polyethylene Glycols/chemistry , Polyglactin 910/chemistry , Tissue Distribution , Xenograft Model Antitumor Assays
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