INTERNATIONAL JOURNAL OF REFRACTORY METALS & HARD MATERIALS
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2024
·
IF 4.2
Xiao Liu,Lu Wang,Zheng-Liang Xue
The hydrogen reduction of MoO 2 is a common method for preparing ultrafine molybdenum powder, which is an important basic material for manufacturing high-performance Mo-based alloys. However, its preparation parameters are usually hard to be controlled. To address this issue, the work conducted the parameter optimization research during the hydrogen reduction process with using central composite design method, and the influence of different parameters such as reaction temperature, yttrium content, and hydrogen flow rate, on the particle size and oxygen content of the prepared molybdenum powder were investigated. The findings showed that the particle size of the prepared molybdenum powder is gradually decreased with the increase of reaction temperature and yttrium content, while gradually increased with the increase of hydrogen flow rate. The oxygen content of the prepared molybdenum powder is gradually decreased with the increase of reaction temperature and hydrogen flow rate, while gradually increased with the increase of yttrium content. Reaction temperature and yttrium content have significant interactions on the particle size and oxygen content are also concluded, and their respective regression model equations are obtained. The result also demonstrated that the particle size and oxygen content of the prepared molybdenum powder had a certain contradictory relationship. Through the comprehensive analysis, the optimal parameters for preparing ultrafine molybdenum powder with a low oxygen content are deduced, that is, reaction temperature: 1200 K, yttrium content: 0.1 mass%, and hydrogen flow rate: 1000 mL/min. Under the conditions, the average particle size and oxygen content of the prepared molybdenum powder are 320 nm and 0.456 mass%, respectively.
研究领域:
材料科学
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化学工程
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产品关联
DOI
高影响因子
Journal of Biomaterials and Tissue Engineering
·
2022
·Vol. 12
·期 9
·1699-1707
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IF 0.144
Li Chunmei,Ji Yubin,Li Wenlan
We designed the present experiment to prepare the sanguinarine chitosan microspheres. First, using the chitosan as a carrier, we prepared sanguinarine microspheres by emulsion cross-linking method, and determined the drug loading and encapsulation efficiency of sanguinarine microspheres
by high performance liquid chromatography (HPLC). Then, taking the particle size as the evaluation indicator, we optimized the preparation process by the central composite design-based response surface methodology (CCD-based RSM). Finally, we performed in vitro release test to examine
the cumulative release of sanguinarine microspheres. As a result, the optimal process conditions: 0.06 g for sanguinarine dosage, 0.07 g for chitosan dosage, 2% for acetic acid concentration, 3:10 for volume ratio of oil to water, 40 °C for emulsion cross-linking temperature, 500 r/min
for rotation speed, and 5% for emulsifier dosage. Under such conditions, the sanguinarine microspheres had round shape, the average particle size was (8.14±0.13) μm, the particle size distribution was 2–20 μm, the drug loading was (4.58±0.93)%, and the
encapsulation efficiency was (54.64±0.39)%, the cumulative release within 24 h was (78.34±1.08)%. In conclusion, we successfully prepared the sanguinarine chitosan microspheres, and they have excellent morphology, suitable particle size, and good sustained-release effect.
研究领域:
药剂学
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生物医学工程
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DOI
高影响因子
International Journal of Nanomedicine
·
2022
·
IF 7.033
Yong-Yan Bei,Xiao-Feng Zhou,Ben-Gang You,Zhi-Qiang Yuan,Wei-Liang Chen,Peng Xia,Yang Liu,Yong Jin,Xiao-Juan Hu,Qiao-Ling Zhu,Chun-Ge Zhang,Xue-Nong Zhang,Liang Zhang
Lactose–palmitoyl–trimethyl–chitosan (Lac-TPCS), a novel amphipathic self-assembled polymer, was synthesized for administration of insoluble drugs to reduce their adverse effects. The central composite design was used to study the preparation technique of harmine (HM)-loaded self-assembled micelles based on Lac-TPCS (Lac-TPCS/HM). Three preparation methods and single factors were screened, including solvent type, HM amount, hydration volume, and temperature. The optimal preparation technique was identified after investigating the influence of two independent factors, namely, HM amount and hydration volume, on four indexes, ie, encapsulation efficiency (EE), drug-loading amount (LD), particle size, and polydispersity index (PDI). Analysis of variance showed a high coefficient of determination of 0.916 to 0.994, thus ensuring a satisfactory adjustment of the predicted prescription. The maximum predicted values of the optimal prescription were 91.62%, 14.20%, 183.3 nm, and 0.214 for EE, LD, size, and PDI, respectively, when HM amount was 1.8 mg and hydration volume was 9.6 mL. HM-loaded micelles were successfully characterized by Fourier-transform infrared spectroscopy, differential scanning calorimetry, X-ray diffraction, and a fluorescence-quenching experiment. Sustained release of Lac-TPCS/HM reached 65.3% in 72 hours at pH 7.4, while free HM released about 99.7% under the same conditions.
研究领域:
药学
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药物递送系统
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纳米技术
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高分子科学
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产品关联
DOI
PubMed
高影响因子
Toxics
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2023
·Vol. 11
·期 3
·203
·
IF 4.6
Qunpo Jia,Yanpeng Cai,Xiao Yuan,Bowen Li,Bo Li
Neonicotinoid insecticides (NEOs) are commonly used to prevent unwanted insects in urban fields. Degradation processes have been one of the important environmental behaviors of NEOs in an aquatic environment. In this research, hydrolysis, biodegradation, and photolysis processes of four typical NEOs (i.e., thiacloprid (THA), clothianidin (CLO), acetamiprid (ACE), and imidacloprid (IMI)) were examined through the adoption of response surface methodology–central composite design (RSM-CCD) for an urban tidal stream in South China. The influences of multiple environmental parameters and concentration levels on the three degradation processes of these NEOs were then evaluated. The results indicated that the three degradation processes of the typical NEOs followed a pseudo-first-order reaction kinetics model. The primary degradation process of the NEOs were hydrolysis and photolysis processes in the urban stream. The hydrolysis degradation rate of THA was the highest (1.97 × 10−5s−1), and that of CLO was the lowest (1.28 × 10−5s−1). The temperature of water samples was the main environmental factor influencing the degradation processes of these NEOs in the urban tidal stream. Salinity and humic acids could inhibit the degradation processes of the NEOs. Under the influence of extreme climate events, the biodegradation processes of these typical NEOs could be suppressed, and other degradation processes could be further accelerated. In addition, extreme climate events could pose severe challenges to the migration and degradation process simulation of NEOs.Keywords:neonicotinoid insecticides (NEOs);degradation kinetics;urban tidal stream;mathematical modeling;central composite design (CCD)
研究领域:
环境科学
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生态学
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DOI
PubMed
高影响因子
ENVIRONMENTAL SCIENCE AND POLLUTION RESEARCH
·
2015
·Vol. 22
·期 17
·13038-13048
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IF 2.828
Wu Hu,Yang Ran,Li Ruihua,Long Chao,Yang Hu,Li Aimin
In this study, an amphoteric grafting chitosan-based flocculant (carboxymethyl chitosan- graft -poly(2-methacryloyloxyethyl) trimethyl ammonium chloride, denoted as CMC- g -PDMC) was applied to removal of the anionic and cationic dyes, acid Green 25 (AG25) and Basic Bright Yellow (7GL), from water. Flocculation conditions have been optimized by response surface methodology (RSM) on the basis of central composite design (CCD) using flocculant dosage, initial solution pH and temperature as input variables. The second-order and cubic regression models, which have been both tested by the analysis of variance (ANOVA), were constructed to link the output response (the dye removal factor) with the aforementioned input variables, respectively. The second-order regression model well described the process of AG25 removal, whereas the cubic one is more suitable for that of 7GL. The effects of those variables on the flocculation performance of CMC- g -PDMC for removal of the two dyes containing opposite charges from aqueous solutions have been studied, and the flocculation mechanisms including the interactive effects between various influencing factors have been discussed in detail also.
研究领域:
环境科学
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高分子化学
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水处理技术
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胶体与界面化学
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污染控制工程
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DOI
高影响因子
JOURNAL OF ANALYTICAL CHEMISTRY
·
2025
·Vol. 80
·期 6
·988-996
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IF 1.1
Mohammadzadeh Ali,Ranjbar Atefeh
A green microextraction method entitled ‘ultrasound-assisted deep eutectic solvent ( DES )-based liquid-liquid microextraction’ was devised for the pre-concentration of cobalt in water samples, with subsequent analysis performed via atomic absorption spectroscopy. Key extraction parameters were optimized, and the method was validated using central composite design for multivariate analysis. The DES was prepared by combining DL-menthol as a hydrogen bond acceptor and dodecanoic acid as a hydrogen bond donor in a 1 : 2 mass ratio. Under optimal conditions, pH of the solution, DES volume (µL), sonication time (min), and mass ratio of DES components were achieved, respectively: 5, 200, 9, and 1 : 2. The method demonstrated excellent linearity in the concentration range of 10–2000 µg/L, with a detection limit of 3.2 µg/L, quantification limits of 10 µg/L, relative standard deviations below 1.8%, and enrichment factors up to 234. The technique was successfully applied to determine cobalt concentrations in real samples.
研究领域:
分析化学
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环境化学
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绿色化学
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痕量元素分析
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DOI
高影响因子
EUROPEAN JOURNAL OF PHARMACEUTICAL SCIENCES
·
2017
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IF 3.756
Jingjing Yao,Yangxin Zhang,Qiming Hu,Decheng Zeng,Fang Hua,Wei Meng,Weiyun Wang,Guan-Hu Bao
With the aim to enhance dissolution rate and bioavailability of paeonol , paeonol-loaded poly(butyl-2-cyanoacrylate) nanocapsules ( [email protected] ) were prepared by interfacial spontaneous polymerization for the first time. Herein, a rotatable central composite design (RCCD) with three-factor five-level was applied to evaluate the optimization experiments. To the maximum percentage encapsulation efficiency (EE%) and minimum particle size (nm) of the [email protected] , a quadratic polynomial model was generated to predict and evaluate the independent variables with respect to the dependent variables. RSM model goodness fitting were confirmed by the ANOVA Table ( P < 0.05) through variance analysis, which predicted values of EE (%) and particle size (R 2 and adjusted R 2 were close to 1, respectively) in good agreement with experimental values. By solving the regression equation and analyzing the response surface, three-dimensional model graphs and plots, the optimal result for the preparation of [email protected] were found to be: pH (2.34), Poloxamer F-68 (0.80% m/v) and ethyl acetate/ α -BCA ratio (16.67 v/v) for the highest EE% (73.58 ± 2.76%) and the smallest particle size (42.06 ± 1.20 nm). The release profiles and antibacterial activity in vitro from the optimal [email protected] were performed. The results indicated that it has slow and well-controlled release, and has strong antibacterial activity in vitro than paeonol. This understanding can help to predict the conditions of optimization of poly(butyl-2-cyanoacrylate) nanoparticles formation and to improve paeonol bioavailability and pharmacological properties.
研究领域:
药学
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纳米技术
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药物递送系统
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生物药剂学
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产品关联
DOI
PubMed
高影响因子
Journal of Ocean University of China
·
2016
·Vol. 15
·期 3
·533-540
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IF 0.509
Fu Zhifei,Li Haihua,Liu Hongbing,Hu Shuman,Li Yueying,Wang Mengxue,Guan Huashi
The response surface methodology (RSM) combined with bioassays was employed to optimize the extraction process of crude fucose-containing sulphated polysaccharides (cFCSP) from Sargassum fusiforme . The central composite design (CCD) was used with four variables, five levels, and four responses. The four variables were pH value of hydrochloric acid solution, extraction temperature (°C), ratio of liquid to raw material (mL g −1 ), and extraction time (h), respectively. Chemical and bioassay indices were used in combination as the response parameters, which included the yield of cFCSP, fucose content, proliferation rate of spleen cells, and lipopolysaccharide-induced proliferation of splenocytes. The experimental data were fitted to a second-order polynomial equation using multiple regression analysis, and examined using the appropriate statistical methods. The best extraction conditions were as follows: the pH value of hydrochloric acid solution was 3.50; the extraction temperature was 100°C; the ratio of liquid to raw material was 15.00 mL g −1 and the extraction time was 2.50 h. The experimental yield was close to the predicted from the model. The extract could promote spleen lymphocyte proliferation, especially the lipopolysaccharide-induced lymphocyte proliferation in vitro, which suggested that its immunomodulatory effect on B lymphocytes. Therefore, cFCSP extracted from S. fusiforme could be utilized as an immunostimulant in functional foods and pharmaceutical industry in future.
研究领域:
海洋生物学
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药理学
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食品科学
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DOI
高影响因子
ENVIRONMENTAL SCIENCE AND POLLUTION RESEARCH
·
2023
·Vol. 30
·期 31
·76992-77005
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IF 5.8
Jia Qunpo,Li Bowen,Li Bo,Cai Yanpeng,Yuan Xiao
Sediment adsorption is one of the main environmental fates of neonicotinoids (NEOs) in aquatic environments. Little information is available on for the adsorption characteristics of NEOs on urban stream sediments. In this study, urban tidal stream sediments were collected to determine the adsorption properties of four selected NEOs. The influence of environmental factors on NEO adsorption was determined by the RSM-CCD method. The NEO adsorption rates on sediments were established by multiple regression equations. As a result, the adsorption of four NEOs onto sediments fitted a linear isotherm model. The adsorption amounts of thiacloprid (THA), clothianidin (CLO), acetamiprid (ACE), and imidacloprid (IMI) were 1.68 to 2.24, 1.71 to 2.89, 1.88 to 3.07, and 2.23 to 3.16 mg/kg, respectively. The adsorption processes of four NEOs on urban sediments were favorable. Moreover, adsorption behaviors of NEOs were typical physical adsorption and readily adsorbed onto urban sediments. The adsorption processes of NEOs were exothermic reactions, and their adsorption rates decreased with increasing pH. Flow rates and organic matter contents could promote the adsorption ratios of typical NEOs. Multiple linear regression was used to assess the relationships between the adsorption rates of NEOs and environmental factors. The p -values of the fitting equations of adsorption rates were all less than 0.05. Within the ranges of concentration of the investigated factors, the multiple regression equations were able to reasonably model and predict the sorption of typical NEOs onto urban stream sediments. Therefore, the adsorption rate equations effectively predicted the NEO adsorption performance of urban streams and were helpful for controlling risk assessment of NEOs.
研究领域:
环境科学
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生态毒理学
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水污染
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吸附过程
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城市水文学
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DOI
高影响因子
Scientific Reports
·
2017
·Vol. 7
·期 1
·1-11
·
IF 4.259
Wang Yaoguang,Wu Di,Wei Qin,Wei Dong,Yan Tao,Yan Liangguo,Hu Lihua,Du Bin
In this study, branched polyethylenimine (PEI) enhanced magnetic carboxymethyl chitosan (MCMC-PEI) was synthesized and applied as adsorbent for the rapid removal of Pb(II) from aqueous solution. The successful synthesis of the adsorbent was proved by scanning electron microscope (SEM), Fourier transform infrared spectrum (FTIR) and X-ray powder diffraction (XRD). Simultaneously, the effect of the parameters such as initial concentration, adsorbent mass and pH of the solution on the removal of Pb(II) was studied by using response surface methodology (RSM). And central composite design (CCD), which is a widely used form of RSM, was employed in the experimental design procedure. The adsorption results revealed that the adsorption process could reach equilibrium rapidly within 10 min. Furthermore, the adsorption kinetic data could be well described by pseudo-second order model. The maximum adsorption capacity was 124.0 mg/g according to the Langmuir-Freundlich model, which fitted the adsorption isotherm of Pb(II) better than Langmuir model and Freundlich model, respectively. Thermodynamic studies (Δ G < 0, Δ H < 0, Δ S > 0) implied a spontaneous and exothermic process in nature. Meanwhile, the fabricated adsorbent exhibited excellent reusability. Therefore, the excellent adsorption property of MCMC-PEI made it a promising application in water treatment.
研究领域:
环境科学
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材料科学
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化学工程
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水处理
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产品关联
DOI
PubMed
高影响因子
Foods
·
2025
·Vol. 14
·期 14
·2509
·
IF 5.1
Wenxi Yu,Qin Lei,Jingxian Jiang,Jianwei Yan,Xijian Yi,Juan Cheng,Siyu Ou,Wenjia Yin,Ziyan Li,Yuru Liao
This study presented a novel antimicrobial packaging PVA/xanthan gum film decorated with green-synthesized silver nanoparticles (AgNPs) derived fromMyrica rubra leaf extract(MRLE) for the first time. Montmorillonite (MMT) was used to improve its dispersion (AgNPs@MMT). The synthesis time, temperature, and concentration of AgNO3were considered using a central composite design coupled with response surface methodology to obtain the optimum AgNPs (2 h, 75 °C, 2 mM). Analysis of substance concentration changes confirmed that the higher phenolic and flavonoid content inMRLEacted as reducing agents and stabilizers in AgNP synthesis, participating in the reaction rather than adsorbing to nanoparticles. TEM, XRD, and FTIR images revealed a spherical shape of the prepared AgNPs, with an average diameter of 8.23 ± 4.27 nm. The incorporation of AgNPs@MMT significantly enhanced the mechanical properties of the films, with the elongation at break and shear strength increasing by 65.19% and 52.10%, respectively, for the PAM2 sample. The films exhibited strong antimicrobial activity against bothEscherichia coli(18.56 mm) andStaphylococcus aureus(20.73 mm). The films demonstrated effective food preservation capabilities, significantly reducing weight loss and extending the shelf life of packaged grapes and bananas. Molecular dynamics simulations reveal the diffusion behavior of AgNPs in different matrices, while the measured silver migration (0.25 ± 0.03 mg/kg) complied withEFSAregulations (10 mg/kg), confirming its food safety. These results demonstrate the film’s potential as an active packaging material for fruit preservation.
研究领域:
食品科学
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纳米技术
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材料科学
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包装技术
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微生物学
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化学合成
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产品关联
DOI
PubMed
高影响因子
JOURNAL OF CHROMATOGRAPHY A
·
2020
·
IF 4.049
Rong Liu,Qing Luo,Zhongqiu Liu,Lingzhi Gong
Liquid chromatography tandem mass spectrometry has been a widely used technique for quantifying oligonucleotides in biological samples. However, lack of simple and efficient sample cleanup approach remains a challenge. Our study aimed to evaluate the major factors during the sample pretreatment process for developing optimal sample preparation workflow for oligonucleotides. In this study, we have employed a model formed with rat plasma containing a 16 mer oligonucleotide standard in order to comprehensively optimize the sample preparation procedures. These included liquid-liquid extraction (LLE), solid-phase extraction (SPE), protein precipitation (PPT) and LLE combined with SPE. LLE with phenol: dichloromethane (2:1, v:v) was found to be the most efficient sample cleanup procedure with low cost and less toxicity. Followed by the extraction, ethanol precipitation (-80 °C, 5 min) was determined to be the optimal drying conditions. Also, mass spectrometric parameters were tuned to optimal conditions. It was found that the central composite design suite was proved to be highly practical for optimizing MS parameters. Finally, the thoroughly optimized sample preparation workflow was fully validated. The developed assay provided a quantitative range of 0.25–1000 nM, with accuracy and precision were < 7.45% and < 12.20%, respectively. Matrix effect and carryover were also evaluated and no significant effect was observed.
研究领域:
分析化学
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药学
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生物化学
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产品关联
DOI
PubMed
高影响因子
危险品化学品经营许可证（带存储）