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1.
Int J Biol Macromol ; 265(Pt 2): 130681, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38458285

RESUMO

The corn starch nanoparticles were prepared by incorporating three kinds of polyphenols, including quercetin, proanthocyanidins and tannin acid. The physicochemical and digestive properties of corn starch nanoparticles were researched. The quercetin showed a higher complexation index than proanthocyanidins and tannin acid when they complexed with corn starch. The mean size of corn starch quercetin, proanthocyanidins and tannin acid were 168.5 nm, 179.1 nm and 188.6 nm, respectively. XRD results indicated that all the corn starch-polyphenols complex showed V-type crystalline structure, the crystallinity of corn starch-quercetin complex was 19.31 %, which showed more formation of amylose-quercetin single helical formed than the other two starch-polyphenol complexes. In vitro digestion revealed that polyphenols could resist digestion and quercetin increased the content of resistant starch from 23.32 % to 35.24 % and polyphenols can form complexes with starch through hydrophobic interactions or hydrogen bonding. This study indicated the hydrophobic polyphenols had a more significant effect on the digestibility of corn starch. And the cell toxicity assessments demonstrated that all nanoparticles were nontoxic and biocompatible.


Assuntos
Proantocianidinas , Amido , Amido/química , Zea mays/química , Taninos , Proantocianidinas/química , Quercetina , Amilose/química , Polifenóis
2.
J Ethnopharmacol ; 326: 117981, 2024 May 23.
Artigo em Inglês | MEDLINE | ID: mdl-38417599

RESUMO

ETHNOPHARMACOLOGICAL RELEVANCE: Sanchen powder is a traditional Tibetan medicine comprising Bambusae Concretio Silicea, Carthami Flos, and Bovis Calculus Artifactus. Bambusae Concretio Silicea is the dried mass of secreted fluid in the stalks of Gramineae plants such as Bambusa textilis McClure or Schizostachyum chinense Rendle. Carthami Flos is the dried flower of Carthamus tinctorius L. in the Compositae plant. Bovis Calculus Artifactus is made from ox bile powder, cholic acid, hyodeoxycholic acid, taurine, bilirubin, cholesterol, and trace elements. Research has evidenced the antibacterial efficacy of Sanchen powder, albeit its active constituents for this effect are yet to be established. AIM OF THE STUDY: To investigate effective compounds, potential targets, and molecular mechanism of Sanchen powder for its antibacterial properties by using network pharmacology combined with in vitro validation, with the aims of observing the action of effective compounds in Sanchen powder and exploring new therapeutic strategies for antibacterial. MATERIALS AND METHODS: In this study, UPLC-Q-TOF-MS was utilized to identify the chemical composition in Sanchen powder and its blood-borne chemical ingredients post-oral intake. A network pharmacology analysis was used to establish the chemical compound in the blood following oral administration-target-disease network. The study aimed to identify antibacterial active ingredients, which were then subjected to molecular docking and pharmacodynamic experiments to verify their efficacy. RESULTS: The findings demonstrate that following oral administration, the blood contains seven key components of Sanchen powder, including bilirubin, glycochenodeoxycholic acid, glycocholic acid, taurocholic acid, phenylalanine, safflomin A, and tryptophan. Additionally, the network pharmacology and molecular docking study results indicate the potential antibacterial effects of bilirubin, glycocholic acid, and glycochenodeoxycholic acid. In vitro antibacterial experiments revealed that bilirubin, glycocholic acid, and glycochenodeoxycholic acid could restrict the growth of the Staphylococcus aureus cell membrane at a certain concentration. Moreover, they exhibited antibacterial effects on Staphylococcus aureus, Pseudomonas aeruginosa, Staphylococcus epidermidis, and Escherichia coli. CONCLUSIONS: Bilirubin, glycocholic acid, and glycochenodeoxycholic acid could be effective therapeutic ingredients for the antibacterial effects of Sanchen powder. These results offer a foundation for further clinical application and research on the antibacterial effect of Sanchen powder, a Traditional Tibetan Medicine.


Assuntos
Cálculos , Medicamentos de Ervas Chinesas , Humanos , Medicina Tradicional Tibetana , Pós , Simulação de Acoplamento Molecular , Ácido Glicoquenodesoxicólico , Antibacterianos/farmacologia , Bilirrubina , Medicamentos de Ervas Chinesas/farmacologia
3.
Food Chem ; 441: 138356, 2024 May 30.
Artigo em Inglês | MEDLINE | ID: mdl-38183721

RESUMO

The reduced antioxidant capacity of trans-resveratrol (Res) than the second generation of Res, namely pterostilbene (Pte), severely prohibits its in-depth intriguing radical-scavenging applications in food formulations. Herein, a unique chemical structure-dependent strategy was proposed to specifically enhance the radical scavenging activity of Res over Pte, relying on the two more hydroxyl groups on the A-benzene ring of Res, thus facilitating its binding with lactoferrin (LF) to form stable complexes through more hydrogen bonds. We prepared LF-Res and LF-Pte complexes, revealed their binding mechanisms by multispectral analysis and molecular docking/dynamics simulations, further evaluated their antioxidant properties via ABTS and DPPH assays and a model of inhibiting apple browning, eventually elucidated their structure-binding-property relationships. This contribution offers a new approach to restore the antioxidant capability of Res, also paves the way to precisely regulate the fascinating bioactivities of hydrophobic compounds by protein-binding in a chemical structure-, especially hydroxyl group-dependent manner.


Assuntos
Antioxidantes , Lactoferrina , Antioxidantes/química , Resveratrol , Simulação de Acoplamento Molecular
4.
Polymers (Basel) ; 16(1)2024 Jan 03.
Artigo em Inglês | MEDLINE | ID: mdl-38201817

RESUMO

Under a global carbon-neutralizing environment, renewable wood is a viable alternative to non-renewable resources due to its abundance and high specific strength. However, fast-growing wood is hard to be applied extensively due to low mechanical strength and poor dimensional stability and durability. In this study, epoxy-acrylic resin-modified wood was prepared by forming a functional monomer system with three monomers [glycidyl methacrylate (GMA), maleic anhydride (MAN), and polyethylene glycol-200-dimethylacrylic acid (PEGDMA)] and filling into the wood cell cavity. The results showed that in the case of an optimal monomer system of nGMA:nPEGDMA = 20:1 and an optimal MAN dosage of 6%, the conversion rate of monomers reached 98.01%, the cell cavity was evenly filled by the polymer, with the cell wall chemically bonded. Thus, a bonding strength of as high as 1.13 MPa, a bending strength of 112.6 MPa and an impact toughness of 74.85 KJ/m2 were applied to the modified wood, which presented excellent dimensional stability (720 h water absorption: 26%, and volume expansion ratio: 5.04%) and rot resistance (loss rates from white rot and brown rot: 3.05% and 0.67%). Additionally, polymer-modified wood also exhibited excellent wear resistance and heat stability. This study reports a novel approach for building new environmentally friendly wood with high strength and toughness and good structural stability and durability.

5.
Diabetes Metab Syndr Obes ; 17: 143-155, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38222035

RESUMO

Purpose: To construct and validate a precise and personalized predictive model for non-alcoholic fatty liver disease (NAFLD) to enhance NAFLD screening and healthcare administration. Patients and Methods: A total of 730 participants' clinical information and outcome measurements were gathered and randomly divided into training and validation sets in a ratio of 3:7. Using the least absolute shrinkage and selection operator (LASSO) regression and multiple logistic regression, a nomogram was established to select risk predictor variables. The NAFLD prediction model was validated through the receiver operating characteristic (ROC) curve, calibration plot, and decision curve analysis (DCA). Results: After random grouping, the cohort comprised 517 in the training set and 213 in the validation set. The prediction model employed nine of the 20 selected variables, namely gender, hypertension, waist circumference, body mass index, blood platelet, triglycerides, high-density lipoprotein cholesterol, plasma glucose, and alanine aminotransferase. ROC curve analysis yielded an area under the curve values of 0.877 (95% Confidence Interval [CI]: 0.848-0.907) for the training set and 0.871 (95% CI: 0.825-0.917) for the validation set. Optimal critical values were determined as 0.472 (0.786, 0.825) in the training set and 0.457 (0.743, 0.839) in the validation set. Calibration curves for both sets showed proximity to the ideal diagonal, with P-values of 0.972 and 0.370 for the training and validation sets, respectively (P > 0.05). DCA indicated favorable clinical applicability of the model. Conclusion: We constructed a nomogram model that could complement traditional NAFLD detection methods, aiding in individualized risk assessment for NAFLD.

6.
Food Chem ; 439: 138046, 2024 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-38029562

RESUMO

In this research, interactions between α-lactalbumin (ALA) and three protopanaxadiol ginsenosides [20(S)-Rg3, 20(S)-Rh2, and 20(S)-PPD] were compared to explore the effects of similar ligand on structure and cytotoxicity of ALA. Multi-spectroscopy revealed the binding between ALA and ginsenoside changed the conformation of ALA, which related to different structures and solubility of ligands. Scanning electron microscope illustrated that all ALA-ginsenoside complexes exhibited denser structures via hydrophobic interactions. Additionally, the cytotoxic experiments confirmed that the cytotoxicity of ginsenoside was enhanced after binding with ALA. Molecular docking showed all three ginsenosides were bound to the sulcus depression region of ALA via hydrogen bonding and hydrophobic interaction. Furthermore, molecular dynamics simulation elucidated the precise binding sites and pertinent system properties. Among all three composite systems, 20(S)-Rh2 had optimal binding affinity. These findings enhanced understanding of the synergistic utilization of ALA and ginsenosides as functional ingredients in food, medicine, and cosmetics.


Assuntos
Ginsenosídeos , Sapogeninas , Ginsenosídeos/farmacologia , Ginsenosídeos/química , Lactalbumina , Simulação de Acoplamento Molecular , Sapogeninas/química , Sapogeninas/farmacologia
7.
Eur J Nutr ; 63(1): 155-172, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-37740812

RESUMO

PURPOSE: Individuals with vitamin D (VD) insufficiency have a greater tendency to develop obesity and have increased systemic inflammation. Gut microbiota are involved in the regulation of host inflammation and energy metabolism, which plays a role in the pathogenesis of obesity. Thus, we aimed to evaluate the effects of different doses of VD3 on body weight, serum lipids, inflammatory factors, and intestinal barrier function in obese mice and to explore the regulatory effect of VD3 on gut microbiota in obese mice. METHODS: Male C57BL/6 J mice received a normal chow diet (NCD, 10% fat) or high-fat diet (HFD, 60% fat) to induce obesity within 10 weeks. Then, HFD mice were supplemented with 5650, 8475, or 11,300 IU VD3/kg diet for 8 weeks. Finally, 16 s rRNA analysis was performed to analyze gut microbiota composition in cecal contents. In addition, body weight, serum lipids, inflammatory factors, and intestinal barrier function were analyzed. RESULTS: VD3 supplementation reduced body weight and the levels of TG, TC, HDL-C, TNF-α, IL-1ß and LPS, and increased ZO-1 in HFD-fed mice. Moreover, it increased α-diversity, reduced F/B ratio and altered microbiota composition by increasing relative abundance of Bacteroidetes, Proteobacteria, Desulfovibrio, Dehalobacterium, Odoribacter, and Parabacteroides and reducing relative abundance of Firmicutes and Ruminococcus. There were significant differences between HFD and NCD groups in several metabolic pathways, including endotoxin biosynthesis, tricarboxylic acid cycle, lipid synthesis and metabolism, and glycolysis. CONCLUSIONS: Low, medium, and high doses of VD3 inhibited weight gain, reduced levels of blood lipids and inflammatory factors, and improved endotoxemia and gut barrier function in obese mice. It also increased the α-diversity of gut microbiota in obese mice and reduced the relative abundance of some intestinal pathogenic bacteria, increased the relative abundance of some beneficial bacteria, and corrected the intestinal flora disorder of obese mice, with the low- and high-dose groups showing better effects than the medium-dose group.


Assuntos
Microbioma Gastrointestinal , Doenças não Transmissíveis , Masculino , Camundongos , Animais , Dieta Hiperlipídica/efeitos adversos , Colecalciferol/farmacologia , Camundongos Obesos , Camundongos Endogâmicos C57BL , Obesidade/metabolismo , Peso Corporal , Inflamação/complicações , Lipídeos , Suplementos Nutricionais
8.
Artigo em Inglês | MEDLINE | ID: mdl-37548789

RESUMO

Establishing a reasonable cost-sharing and compensation mechanism for air pollution control is a prerequisite for realizing inter-regional cooperative treatment. Taking inter-provincial sulfur dioxide (SO2) emissions in China from 2005 to 2019 as the research object, this paper proposes a data-driven approach to establish a cost-sharing index system of regional SO2 treatment in four dimensions and construct a cost-sharing and compensation scheme using the entropy-TOPSIS method. The results revealed that there are significant spatial and temporal differences in the treatment cost of SO2 emission, and the total SO2 treatment costs at the national level increased first and then decreased during the study period, meanwhile, the regional SO2 treatment costs are much higher in the less economically developed regions such as the central and western regions than in economically developed eastern coastal regions. The design of the cost-sharing and compensation mechanism of SO2 treatment should consider the regional differences in abatement capacity, abatement potential, abatement responsibility, and development demands. The economically developed regions should share higher treatment costs according to their historical cumulative abatement responsibilities, and provide economic compensation and technical support to the less economically developed regions. Specifically, the marginal abatement cost in the more economically developed eastern region is much higher than that in the less economically developed central and western areas due to their large abatement responsibility and strong reduction capacity but insufficient abatement potential, so the eastern regions can transfer part of their abatement responsibility to the central and western regions using economic compensation. Reasonable cost sharing and horizontal compensation can help promote regional cooperation and synergistic management in air pollution abatement. Finally, corresponding policy recommendations are given to provide a decision basis for cross-regional cooperation in air pollution control.

9.
Polymers (Basel) ; 15(4)2023 Feb 10.
Artigo em Inglês | MEDLINE | ID: mdl-36850165

RESUMO

Waterborne polyurethane coatings (WPU) are widely used in various types of coatings due to their environmental friendliness, rich gloss, and strong adhesion. However, their inferior mechanical properties and solvent resistance limit their application on the surface of wood products. In this study, graphene oxide (GO) with nanoscale size, large surface area, and abundant functional groups was incorporated into WPU by chemical grafting to improve the dispersion of GO in WPU, resulting in excellent mechanical properties and solvent resistance of WPU coatings. GO with abundant oxygen-containing functional groups and nanoscale size was prepared, and maintained good compatibility with WPU. When the GO concentration was 0.7 wt%, the tensile strength of GO-modified WPU coating film increased by 64.89%, and the abrasion resistance and pendulum hardness increased by 28.19% and 15.87%, respectively. In addition, GO also improved the solvent resistance of WPU coatings. The chemical grafting strategy employed in this study provides a feasible way to improve the dispersion of GO in WPU and provides a useful reference for the modification of waterborne wood coatings.

10.
Polymers (Basel) ; 15(23)2023 Dec 04.
Artigo em Inglês | MEDLINE | ID: mdl-38232038

RESUMO

Hybrid aluminum dialkylphosphinates were synthesized from mixed diethyl-, ethylisobutyl-, and diisobutylphosphinates and Al3+ in water. The XRD, DSC, and TGA results of these Al phosphinates established that phosphinate ligands are randomly distributed in the species. The thermal and thermoxidative stabilities of the hybrid phosphinates were easily adjustable by varying the ratio of phosphinate ligands, a desirable feature for efficient flame retardants. The hybrid aluminum dialkylphosphinates with a relatively low ratio of diethylphosphinate demonstrated higher efficiency than Al diethylphosphinate and Al diisobutylphosphinate in flame-retarding polyamide 66. Detailed investigations on the thermal and thermoxidative stabilities of Al dialkylphosphinates and the morphologies of char obtained in UL-94 tests revealed that timely vaporization of degradation products of hybrid dialkylphosphinates at a temperature which closely matches the degradation temperature of polyamides and their ability to promote char formation of polyamides are two key factors which contribute to the excellent performance of hybrid aluminum dialkylphosphinates.

11.
Polymers (Basel) ; 14(23)2022 Dec 02.
Artigo em Inglês | MEDLINE | ID: mdl-36501668

RESUMO

Wood is a viable alternative to traditional steel, cement, and concrete as a structural material for building applications, utilizing renewable resources and addressing the challenges of high energy consumption and environmental pollution in the construction industry. However, the vast supply of fast-growing poplar wood has bottlenecks in terms of low strength and dimensional stability, making it difficult to use as a structural material. An environmentally friendly acrylic resin system was designed and cured in this study to fill the poplar cell cavities, resulting in a new type of poplar laminated veneer lumber with improved mechanical strength and dimensional stability. The optimized acrylic resin system had a solid content of 25% and a curing agent content of 10% of the resin solid content. The cured filled poplar veneer gained 81.36% of its weight and had a density of 0.69 g/cm3. The static flexural strength and modulus of elasticity of the further prepared laminated veneer lumber were 123.12 MPa and 12,944.76 MPa, respectively, exceeding the highest flexural strength required for wood structural timber for construction (modulus of elasticity 12,500 MPa and static flexural strength 35 MPa). Its tensile strength, impact toughness, hardness, attrition value, water absorption, water absorption thickness expansion, and water absorption width expansion were 58.81%, 19.50%, 419.18%, 76.83%, 44.38%, 13.90%, and 37.60% higher than untreated laminated veneer lumber, demonstrating improved mechanical strength and dimensional stability, significantly. This method provides a novel approach to encouraging the use of low-value-added poplar wood in high-value-added structural building material applications.

12.
Zhongguo Zhong Yao Za Zhi ; 47(15): 3994-4006, 2022 Aug.
Artigo em Chinês | MEDLINE | ID: mdl-36046888

RESUMO

The detection method of characteristic spectrum for reference samples was established by preparing 15 batches of the reference samples of Huagan Decoction, and the peak attribution and the similarity range in the characteristic spectrum were clarified. The ranges of paste-forming rate, content, and transfer rate of the index components including geniposide, paeonol, and paeoniflorin were analyzed. The key quality attribute of the reference samples of Huagan Decoction was defined. The results showed that the 15 batches of the reference samples of Huagan Decoction had good similarities in the characteristic spectrum, which were all higher than 0.9. According to the information of characteristic peak, there were 18 characteristic peaks in the whole prescription, including seven common characteristic peaks from green tangerine peel and dried tangerine peel, four characteristic peaks from tree peony root bark(three of them were common characteristic peaks from tree peony root bark and red peony root), five characteristic peaks from cape jasmine fruit, one characteristic peak from paniculate bolbostemma, and one characteristic peak from oriental waterplantain rhizome.The paste-forming rate of the 15 batches of reference samples was 14.73%-18.83%. The content of geniposide was 1.68%-2.87%, with the average transfer rate of 70.05%±11.13%. The content of paeonol was 0.10%-0.16%, with the average transfer rate of 9.38%±1.78%. The content of paeoniflorin was 1.94%-2.74%, with the average transfer rate of 36.69%±4.63%. This study analyzed the quality value transfer of the reference samples of Huagan Decoction by the evaluation mode of combining the characteristic spectrum, the paste-forming rate, and the content of index components. The findings of this study initially established a stable and feasible standard decoction evaluation method and provided references for the quality control and the subsequent development of relevant preparations of Huagan Decoction.


Assuntos
Medicamentos de Ervas Chinesas , Paeonia , Cromatografia Líquida de Alta Pressão , Prescrições , Controle de Qualidade
13.
J Ethnopharmacol ; 298: 115629, 2022 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-35988839

RESUMO

ETHNOPHARMACOLOGICAL RELEVANCE: Huagan Decoction (HGD), a famous traditional Chinese medicine (TCM) formula, has been widely used in the treatment of reflux esophagitis (RE). However, its effective compounds, potential targets and molecular mechanism remain unclear. AIM OF THE STUDY: To investigate effective compounds, potential targets and molecular mechanism of HGD against RE by using network pharmacology combined with in vitro validation, with the aims of observing the action of HGD and exploring new therapeutic strategies for RE treatment. MATERIALS AND METHODS: Effective compounds and potential targets of HGD, as well as related genes of RE, were collected from public databases. Pharmacological clustering and Gene Ontology (GO) enrichment analysis were applied to find targets that involving in the anti-inflammatory module. The pathways were drawn using Cytoscape 3.8.0. Important ingredients, potential targets, and signaling pathways were determined through the construction of protein-protein interaction (PPI), GO and Kyoto Encyclopedia of Genes and Genomes (KEGG). Subsequently, cell experiments were carried out. RESULTS: A total of 54 active ingredients and 240 RE-related gene targets of HGD were identified. The active compound-target network was visualized and pharmacological clustering further sorted 53 proteins that involve in the regulation of inflammatory responses. GO analysis confirmed the classification was statistically significant. Analysis of compound-target network revealed that quercetin and geniposide may be key ingredients for the anti-inflammatory effect of HGD against RE. The potential targets regulated by HGD are IL-6, IL-1ß, PTGS2, AKT1, TNF-α, MAPK1, IL-8, IL-10, CCL2 and MAPK3. In vitro experiment showed that quercetin and geniposide could inhibit the inflammatory response of HET-1A cells through p38MAPK/NF-κB signaling pathway, which was consistent with the prediction by the network pharmacology approach. CONCLUSIONS: Geniposide and quercetin could be effective therapeutic ingredients for the HGD against RE. They play anti-inflammatory effects via down-regulating the pro-inflammatory cytokines and the conduction of p38MAPK/NF-κB signal. This research provides a comprehensive study on the active components, potential targets, and molecular mechanisms of HGD against RE. Moreover, the study supplies a feasible approach to reveal the mechanisms of TCM formula.


Assuntos
Medicamentos de Ervas Chinesas , Esofagite Péptica , Anti-Inflamatórios/farmacologia , Anti-Inflamatórios/uso terapêutico , Medicamentos de Ervas Chinesas/farmacologia , Medicamentos de Ervas Chinesas/uso terapêutico , Esofagite Péptica/tratamento farmacológico , Humanos , Medicina Tradicional Chinesa , Simulação de Acoplamento Molecular , NF-kappa B , Farmacologia em Rede , Quercetina
14.
Zhongguo Zhong Yao Za Zhi ; 47(8): 2099-2108, 2022 Apr.
Artigo em Chinês | MEDLINE | ID: mdl-35531726

RESUMO

According to the polarity of different components in Sanpian Decoction, two fingerprints were established. Then the substance benchmark freeze-dried powder of 15 batches of Sanpian Decoction was prepared, followed by the determination of the fingerprints, index component content, and dry extract rates, the identification of attribution of characteristic peaks, and the calculation of similarities between these fingerprints and the reference(R), the content and transfer rate ranges of ferulic acid, sinapine thiocyanate, liquiritin, and glycyrrhizic acid, and the dry extract rate range. The results showed that the similarities of 15 batches of the substance benchmark fingerprints with R were all greater than 0.900.Further summarization of the characteristic peaks revealed that there were a total of 20 characteristic peaks in fingerprint 1, among which, eight were from Sinapis Semen, four from Paeoniae Radix Alba, six from Chuanxiong Rhizoma, and two from Glycyrrhizae Radix et Rhizoma. A total of 16 characteristic peaks were observed in fingerprint 2, including one from Sinapis Semen, three from Paeoniae Radix Alba, eight from Chuanxiong Rhizoma, and four from Glycyrrhizae Radix et Rhizoma. The average dry extract rate of 15 batches of substance benchmarks was 18.25%, with a dry extract rate range of 16.28%-20.76%. The index component content and transfer rate ranges were listed as follows: 0.15%-0.18% and 38.81%-58.05% for ferulic acid; 0.26%-0.42% and 36.51%-51.02% for sinapine thiocyanate; 0.09%-0.15% and 48.80%-76.61% for liquiritin; 0.13%-0.24% and 23.45%-35.61% for glycyrrhizic acid. The fingerprint, dry extract rate, and index component content determination was combined for analyzing the quality value transfer of substance benchmarks in the classic prescription Sanpian Decoction.The established quality evaluation method for the substance benchmarks was stable and feasible, which has provided a basis for the quality control of Sanpian Decoction and the follow-up development of related preparations.


Assuntos
Medicamentos de Ervas Chinesas , Paeonia , Benchmarking , Cromatografia Líquida de Alta Pressão , Ácido Glicirrízico/análise , Controle de Qualidade , Tiocianatos
15.
Polymers (Basel) ; 14(8)2022 Apr 12.
Artigo em Inglês | MEDLINE | ID: mdl-35458320

RESUMO

Fast-growing poplar wood has the bottleneck problems of inferior mechanical strength and poor dimensional stability. In this study, the wood was modified by combined treatments of pre-compression and post-vacuum-thermo modification to improve its mechanical strength and dimensional stability, simultaneously; in addition, the variation law of mechanical properties of the wood with compression ratio as well as the improvement effect of dimensional stability of the treated wood were mainly studied. The results show that the optimal temperature and time of the vacuum-thermo modification were 190 °C and 10 h, respectively. Under these conditions, the structure of pre-compressed and post-vacuum-thermally modified wood (CT wood) is gradually densified with the increase in the compression ratio, which results in the continuous enhancement of mechanical properties. Meanwhile, the anti-swelling efficiency (ASE) of the CT wood after water absorption is correspondingly better than that of the compressed wood before thermal modification, indicating that the dimensional stability of compressed wood was improved by the thermal modification. When the compression ratio was 70%, the modulus of rupture (MOR) and impact toughness of CT wood was 176 MPa and 63 KJ/m2, which was 125% and 59% higher than that of untreated wood, respectively. The ASE was also 26% higher than that of the wood with sole compression. Therefore, this method improves the mechanical strength and dimensional stability of wood simultaneously, and it provides a scientific basis for optimization of the reinforcing modification process of fast-growing wood.

16.
Zhongguo Zhong Yao Za Zhi ; 47(2): 358-366, 2022 Jan.
Artigo em Chinês | MEDLINE | ID: mdl-35178977

RESUMO

Taste is an important factor affecting the medicinal properties of oral preparations and patient compliance with medication, and also an important evaluation index for oral preparation design and clinical application. How to characterize the taste objectively, accurately, simply, and efficiently is a bottleneck problem that restricts the taste design, development, and utilization of oral preparations. At present, the commonly used taste assessment methods for oral preparations are traditional human taste panel, electronic tongue, animal preference test, in vitro release study, and electrophysiological test. The traditional human taste panel is the first choice for taste evaluation, but it is limited by poor subjectivity and reproducibility. Therefore, despite some limitations, the other four taste assessment methods have been applied in the pharmaceutical industry as auxiliary methods. This study reviewed the detection principles, applicability, advantages, and disadvantages of the above methods to provide references for the taste correction research and taste assessment of oral preparations, improve patient compliance and the competitiveness of oral preparation products in the industry, and promote the development of oral preparation technologies.


Assuntos
Preparações Farmacêuticas , Paladar , Administração Oral , Animais , Nariz Eletrônico , Humanos , Reprodutibilidade dos Testes
17.
J Colloid Interface Sci ; 604: 650-659, 2021 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-34280763

RESUMO

Developing an efficient bifunctional catalyst for Hydrogen Evolution Reaction (HER) and Oxygen Evolution Reaction (OER) in water splitting technology is very attractive for clean energy. Here, a new Co-Fe-B ternary catalyst with improved crystallinity is successfully synthesized by combining the chemical reduction and subsequent solid-state reaction method. Synchrotron-based X-ray absorption near-edge structure (XANES) and X-ray photoelectron spectroscopy (XPS) indicate the electronic structure redistribution is favor for the improved performance. The overpotential is only 129 mV and 280 mV for hydrogen evolution reaction (HER) and oxygen evolution reaction (OER) in alkaline condition, the corresponding Tafel slope is 67.3 mV dec-1 and 38.9 mV dec-1. Density functional theory calculations distinguish that the ternary crystalline Co-Fe-B catalysts are thermodynamically favorable for HER and OER. The actual active species of the ternary catalyst in OER is the CoOOH and FeOOH as indicated in ex situ Raman spectra. The present work may introduce promising crystallinity borides material for the anode and cathode of water splitting device.

18.
Zhongguo Zhong Yao Za Zhi ; 46(4): 810-819, 2021 Feb.
Artigo em Chinês | MEDLINE | ID: mdl-33645085

RESUMO

By preparing 15 batches of lyophilized powder samples of substance benchmark in Houpo Wenzhong Decoction,the fingerprint,index component content and extract rate were determined,and the characteristic peaks,the range of similarity with the reference map,the content range and transfer rate range of magnolol,hesperidin,glycyrrhizic acid and pinocembrin,the extract rate range and the change range were clarified. The results showed that the similarity between the fingerprint of substance benchmark and the reference map R generated from the 15 batches of substance benchmark samples was higher than 0. 90. The assignment of the characteristic peaks in the full prescription's fingerprint of the herbs except Poria cocos was clarified. Nineteen characteristic peaks were assigned,and 12 characteristic peaks were assigned by the reference substance,of which 4 were from Magnolia ocinalis Cortex,5 from Exocarpium Citri Rubrum,2 from Radix aucklandiae,3 from Glycyrrhiza Radix et Rhizoma,4 from Semen Alpiniae Katsumadai,and one from Rhizoma Zingiberis and Zingiber officinale Roscoe. The index component content range and transfer rate range were 0. 80%-1. 14% and 20. 25%-39. 61% for hesperidin,0. 49%-0. 79% and 23. 09%-33. 87%for glycyrrhizic acid,0. 03%-0. 07% and 3. 55%-10. 09% for pinocembrin,0. 15%-0. 38% and 8. 08%-24. 35% for magnolol. The extract rate range and the change range were22. 60%-25. 57% and 12. 67%-23. 68% respectively. In this study,we introduced the concepts of index component content,fingerprint,extract rate,explored the transfer relation of quality value transmitting of substance benchmark in Houpo Wenzhong Decoction,and initially established the quality standard of Houpo Wenzhong Decoction,all of which would provide ideas for the development and research of similar prescriptions.


Assuntos
Medicamentos de Ervas Chinesas , Glycyrrhiza , Benchmarking , Cromatografia Líquida de Alta Pressão , Controle de Qualidade
19.
Math Biosci Eng ; 17(6): 6928-6944, 2020 10 15.
Artigo em Inglês | MEDLINE | ID: mdl-33378882

RESUMO

Persistent Scatterer SAR Interferometry (PSInSAR) is known as one of the most effective technique for monitoring and analyzing ground deformation. It is a key step that how to identify Persistent Scatterers (PS) effectively and automatically from time-series SAR images. In the past research, one pixel will be classified to "PS" set or "no-PS" set clearly by one or more threshold rules for PS features. However, it is easy to fall into the 'either this or that' logical paradox in some cases because the covered objects in study area usually possess ambiguous boundary for interested characteristics. In this paper, a fuzzy PS concept is present and a fuzzy identification method is designed based on fuzzy set theory by taking the fuzzy characteristics of the pixels into account. Two groups of real data tests indicate that the new method can not only recognize more effective and reliable PS, but also can obtain the better quality results of selected PS, which can be used to evaluate the result of deformation and further improve the PSInSAR technology.

20.
Polymers (Basel) ; 12(2)2020 Jan 23.
Artigo em Inglês | MEDLINE | ID: mdl-31979373

RESUMO

: The intumescent process of sodium (substituted) phenolates has been studied. The generation of hydrogen radical via a homolytic cleavage of the Ar-H bond and the subsequent hydroarylation of phenolates to cyclohexadienes along with cyclization and elimination reactions of cyclohexadienes are critical steps in the base promoted intumescence of phenols. The substituents show great influence on the intumescence of phenolates. Phenolates substituted with a weak electron donating group enable intumescence while those with an electron withdrawing group or strong electron donating group suppresses intumescence. This distinction can be justified by both electronic and steric effects of substituents on the generation of hydrogen radical and the degree of hydroarylation.

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