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1.
Small ; : e2403423, 2024 Sep 10.
Artigo em Inglês | MEDLINE | ID: mdl-39254289

RESUMO

Determining molecular structures is foundational in chemistry and biology. The notion of discerning molecular structures simply from the visual appearance of a material remained almost unthinkable until the advent of machine learning. This paper introduces a pioneering approach bridging the visual appearance of materials (both at the micro- and nanostructural levels) with traditional chemical structure analysis methods. Quaternary phosphonium salts are opted as the model compounds, given their significant roles in diverse chemical and medicinal fields and their ability to form homologs with only minute intermolecular variances. This research results in the successful creation of a neural network model capable of recognizing molecular structures from visual electron microscopy images of the material. The performance of the model is evaluated and related to the chemical nature of the studied chemicals. Additionally, unsupervised domain transfer is tested as a method to use the resulting model on optical microscopy images, as well as test models trained on optical images directly. The robustness of the method is further tested using a complex system of phosphonium salt mixtures. To the best of the authors' knowledge, this study offers the first evidence of the feasibility of discerning nearly indistinguishable molecular structures.

2.
J Hazard Mater ; 454: 131467, 2023 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-37104957

RESUMO

1,3-Dinitrobenzene (1,3-DNB) is listed by the USEPA as a priority pollutant. 1,3-DNB has two nitro functional groups (-NO2) bound to the benzene ring, with a +III nitrogen oxidation states, and strong electronegativity, and therefore can be reductively degraded by gaining electrons. Weeds that contain a high proportion of polyphenols can supply electrons and act as natural reducing agents. This study investigated the potential of various weeds to reductively remove 1,3-DNB from aqueous phase. The Taguchi L9 Orthogonal experimental design method was used to explore the optimum operational parameters. According to the analyzed characteristics of weeds, including total phenol content, antioxidant capacity, metal chelating capacity, reducing capacity, and environmental adaptability, the weed Sphagneticola trilobata, containing 11.93 mg of gallic acid equivalent per gram of weed (mg-GAE/g-weed), was selected for 1,3-DNB degradation experiments. The results showed that the optimum reaction conditions for the degradation of 1,3-DNB in the aqueous phase using Sphagneticola trilobata were: pH 3, a weed dose of 10 g/L, reaction time of 14 day, and initial 1,3-DNB concentration of 0.5 mM. According to ANOVA analysis, the weed dose was the most significant factor in the experiment, and each 1 mg of 1,3-DNB degraded required 120 mg of dry weeds.

3.
Materials (Basel) ; 15(14)2022 Jul 14.
Artigo em Inglês | MEDLINE | ID: mdl-35888357

RESUMO

In this study, laser-assisted machining experiments are carried out on silicon carbide (SiC) ceramic materials by a turning process, and laser power, cutting depth, rotational speed, and feed speed are selected as research factors. In order to improve the surface processing quality of laser-assisted turning of SiC ceramics and obtain the smallest surface roughness, the orthogonal method and response surface method are used to investigate the effect of various factors on surface roughness. The effect of various factors on surface roughness is evaluated by variance analysis, mean analysis, main effect diagram, 3D response surface, and corresponding contour diagram. The surface roughness prediction model is established based on the response surface method, and the prediction error is 4.1% with high accuracy. The experimental results show that laser power and cutting depth are the most significant factors affecting surface roughness, and rotational speed is a significant factor affecting surface roughness. Under the optimum process conditions, the smallest surface roughness Ra obtained by the response surface method is 0.294 µm, which is lower than 0.315 µm obtained by the orthogonal method, and the surface quality is higher. Therefore, the optimal process parameters of the response surface method can obtain the smallest surface roughness and higher surface quality in laser-assisted turning of SiC ceramics.

4.
Artigo em Chinês | WPRIM (Pacífico Ocidental) | ID: wpr-882067

RESUMO

Objective To establish an HPLC method for simultaneous assay of macrocyclic polyphenols from Penthorum chinense Pursh, pinocembrin-7-O-[4'', 6''-(S)-hexahydroxydiphenoyl]-β-D-glucose (PHG), pinocembrin-7-O-[3''-O-galloyl-4'', 6''-(S)-hexahydroxydiphenoyl]-β-D-glucose (PGHG) and pinocembrin dihydrochalcone-7-O-[3''-O-galloyl-4'', 6''-(S)-hexahydroxydiphenoyl]-β-D-glucoside or thonningianin A (THA), and optimize the extraction process. Methods The total extraction rate of PHG, PGHG, THA was used as an investigated index to analyze the extracts from Penthorum chinense Pursh. Orthogonal design was applied to evaluate solvent amount, extraction time, solvent concentration and extraction times as the influencing factors for the optimal extraction process of macrocyclic polyphenols from Penthorum chinense Pursh. Results When this content assay method was adopted, there were good linear relationships for PHG, PGHG, THA in the linear range. The recoveries were between 100.90% to 102.04% with the RSDs below 1.5%. The optimal extraction process was involved in cutting Penthorum chinense Pursh into 3-5 cm, adding 10 times 80% ethanol aqueous solution by volume and refluxing 2 hours twice. The extraction rate of macrocyclic polyphenols was above 90% with this process. Conclusion This assay method is accurate, stable, and repeatable. The optimized extraction process is stable and feasible for further development and utilization.

5.
Waste Manag ; 113: 488-496, 2020 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-32619783

RESUMO

With the purpose of fully understanding the potential toxicity of heavy metals of various particle sizes in fly ash (FA) and finding an optimal chemical reagent stabilization scheme for fly ash with single or mixture reagents, basic physicochemical characteristics of FA was investigated using multiple chemical stabilization reagent schemes to stabilize heavy metals. The following compounds were used to develop single and mixed chemical stabilization schemes for heavy metals in waste incineration FA: sodium sulfide (Na2S), sodium dihydrogen phosphate (NaH2PO4), ammonium dibutyl dithiophosphate (DDTP), and 2,4,6-tri-mercapto-S-triazine trisodium salt (TMT-15). The results showed that the various particle sizes of FA were mainly distributed in the range of 48-1700 µm. FA was packed with heavy metals, and the smaller the particle size, the more toxic it was. The speciation distribution of Cu, Zn, Pb, Cd, and Cr in different particle sizes was identical to that of the mixed samples. In the experiments of single reagent stabilization scheme, 8% Na2S, 8% NaH2PO4, 4.2% DDTP or 4.2% TMT-15 could decrease the leaching concentration to meet the limits set by Chinese law, but 8% Na2S adding scheme had the lowest cost among them. However, in the mixture reagent scheme, 1.2% Na2S, 1.2% NaH2PO4 and 0.8% DDTP was more effective and even cheaper than other mixture or single schemes.


Assuntos
Metais Pesados/análise , Eliminação de Resíduos , Carbono , Cinza de Carvão , Incineração , Material Particulado , Resíduos Sólidos
6.
J Appl Biomater Funct Mater ; 18: 2280800019887906, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-31996069

RESUMO

Fast degradation rate and inhomogeneous corrosion are obstacles for magnesium alloy bio-corrosion properties. In this paper, a quaternary Mg-Zn-Ca-Mn alloy was designed by an orthogonal method and prepared by vacuum induction melting to investigate its bio-corrosion. Microstructure, corrosion morphology, and bio-corrosion properties of as-cast alloys 1 to 5 with good corrosion resistance were characterized by scanning electron microscopy, energy dispersive X-ray spectroscopy, and X-ray diffraction with immersion and electrochemical tests in simulated body fluid (SBF), respectively. Both the orthogonal method and in vitro degradation experiments demonstrated that alloy 3 exhibited the lowest degradation rate among the tested quaternary Mg-Zn-Ca-Mn alloys. Then, as-cast alloy 3 was treated by solid-solution and solid-solution aging. In vitro experimental results indicated that as-cast alloy 3 showed better corrosion resistance than heat-treated specimens and the average corrosion rate was approximately 0.15 mm/y. Heat-treated alloy 3 exhibited more uniform corrosion than as-cast alloy specimens. These results suggest that alloy 3 has the potential to become a biodegradable candidate material.


Assuntos
Ligas/química , Soluções/química , Líquidos Corporais/química , Cálcio/química , Corrosão , Técnicas Eletroquímicas , Magnésio/química , Manganês/química , Microscopia Eletrônica de Varredura , Espectrometria por Raios X , Temperatura , Vácuo , Zinco/química
7.
Artigo em Chinês | WPRIM (Pacífico Ocidental) | ID: wpr-481443

RESUMO

This study was aimed to optimize the extraction process conditions of lycopene in tomato. Ketchup was used as raw material. Method verification, single factor experiment and orthogonal method were used in the study on extraction process of lycopene. The results showed that the best optimization process conditions of lycopene extraction with ethyl acetate: extraction temperature at 50℃, extraction time for 40 min, ethyl acetate concentration of 80%, solid-to-liquid ratio of 1?2 (g·mL-1). Under these conditions, the extraction rate of lycopene reached 15.564 mg·100g-1. It was concluded that the extraction process of lycopene can provide experimental basis for further development and utilization of lycopene.

8.
Artigo em Chinês | WPRIM (Pacífico Ocidental) | ID: wpr-564475

RESUMO

Objective:To study the extraction process of AWei capsule.Methods:Taking the contents of gallic acid and the yield of extracts as assessment index to optimize water extraction process of AWei capsule with orthogonal experimental design.Taking the contents of magnolol,honokiol and the yield of extracts as assessment index to optimize ethanol extraction process of AWei capsule with orthogonal experimental design.Results:The optimal water extraction process of AWei capsule was extracting twice,every time lasted 1.5h,every time added 14 times water.The optimal ethanol extraction process of AWei capsule was using 80%ethanol as solvent,extracting twice,every time lasted 1.5h,every time added 6 times solvent.Conclusion:The optimized extraction process is stable and reasonable.

9.
China Pharmacy ; (12)2005.
Artigo em Chinês | WPRIM (Pacífico Ocidental) | ID: wpr-526204

RESUMO

OBJECTIVE:To optimize the extraction technique of tiannian capsules. METHODS:The extraction technique was selected by orthogonal method,with the contents of radix astragali and polycose,as well as the recovery of dry ointment as indicators,the influential factors for the extraction of effective ingredients that included the amount of adding water,length of decocting time and frequencies of decocting were studied.RESULTS:The optimal extraction technique is that medicinal herb is decocted in water 6 times as much as the herb for 3 times with 1 h per time.CONCLUSION:The optimized extraction technique is scientific,economic and practicable,which can be a guideline for manufacturing.

10.
Artigo em Chinês | WPRIM (Pacífico Ocidental) | ID: wpr-559504

RESUMO

AIM:To choose the best formulation of marzulene-S grranuls oral membrane and to evaluate the clinical effects.METHODS: Orthogonal method was used for studying.Take the appearance,viscidity and dissolubility of the oral membrane as the indexes of scoring 108 cases of patients were chosen and divided into two groups randomly.58 case were treated with marzulene-S grranuls oral membrane and 50 cases were treated with gargarisma chlorhexidine as the control group.RESULTS: The best prescription is sodium carboxymethyl cellulose 4%,polyvinyl alcohol_(1750) 1% and polyvinyl alcohol_(17-88) 3%.CONCLUSION: The design of the formulation is reasonable and the clinical effect was satisfactory.

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