Membranes
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2020
·Vol. 10
·期 1
·12
·
IF 3.094
Xi Yang
The interfacial polymerization (IP) of piperazine (PIP) and trimesoyl chloride (TMC) has been extensively utilized to synthesize nanofiltration (NF) membranes. However, it is still a huge challenge to monitor the IP reaction, because of the fast reaction rate and the formed ultra-thin film. Herein, two effective strategies were applied to reduce the IP reaction rate: (1) the introduction of hydrophilic interlayers between the porous substrate and the formed polyamide layer, and (2) the addition of macromolecular additives in the aqueous solution of PIP. As a result, in situ Fourier transform infrared (FT-IR) spectroscopy was firstly used to monitor the IP reaction of PIP/TMC with hydrophilic interlayers or macromolecular additives in the aqueous solution of PIP. Moreover, the formed polyamide layer growth on the substrate was studied in a real-time manner. The in situ FT-IR experimental results confirmed that the IP reaction rates were effectively suppressed and that the formed polyamide thickness was reduced from 138 ± 24 nm to 46 ± 2 nm according to TEM observation. Furthermore, an optimized NF membrane with excellent performance was consequently obtained, which included boosted water permeation of about 141–238 (L/m2·h·MPa) and superior salt rejection of Na2SO4> 98.4%.Keywords:interfacial polymerization;in situ FT-IR spectroscopy;thin-film composite membrane;nanofiltration membrane
研究领域:
材料科学
·
化学工程
✓ 已验证
产品关联
DOI
PubMed
高影响因子
JOURNAL OF CONTROLLED RELEASE
·
2016
·
IF 7.441
Wenting Song,Peng Quan,Shanshan Li,Chao Liu,Siji Lv,Yongshan Zhao,Liang Fang
In patches, a drug must release from patches prior to its percutaneous absorption. Chemical enhancers have been used for several decades, but their roles in drug release from patches are poorly understood. In this work, the roles of chemical enhancers in bisoprolol tartrate (BSP-T) release from patches were probed in vitro and in vivo. More importantly, an innovative mechanism insight of chemical enhancers in drug release process was provided at molecular level. FT-IR spectroscopy and molecular modeling were employed to investigate the influence of chemical enhancers on drug-adhesive interaction. The results showed chemical enhancers like Span 80 , which had a strong ability forming hydrogen bonds , could decrease drug-adhesive interaction leading to the release of drug from adhesive of patches. Thermal analysis was conducted to research the influence of chemical enhancers on the thermodynamic properties of patch system. It showed that chemical enhancers promoted the formation of free volume of adhesive, which facilitated drug release process. By contrast, the influence on the thermodynamic properties of BSP-T was less effective in influencing BSP-T release process. In conclusion, chemical enhancers played an important role in facilitating BSP-T release from the adhesive DURO-TAK® 87-2287 of patches by decreasing drug-adhesive interaction and promoting the formation of free volume of adhesive. This work may be an important step in understanding the important roles of chemical enhancers in drug release process.
研究领域:
药剂学
·
生物医学工程
·
药物化学
✓ 已验证
DOI
高影响因子
HIGH PERFORMANCE POLYMERS
·
2023
·
IF 2.1
Junjie Zhou,Kangkang Guo,Fan Wang,Yaping Zhu,Huimin Qi
Herein, the catalytic effects of aromatic amines with different structures on the room temperature curing of bisphenol E cyanate (BECy) have been studied using differential scanning calorimetry (DSC) and Fourier transform infrared (FT-IR) spectroscopy. Our results revealed that the mixed amine comprised of aniline and N,N-dimethyl-p-phenylenediamine (AN/NNDPA) bearing primary amino groups in its structure was a highly effective catalyst for the room temperature curing of cyanate esters. When the cyanate ester and mixed amine were combined at a molar ratio of 100:5 and cured at room temperature for 5 days, the curing degree of BECy resin reached 79.7%. The room temperature curing mechanism of the BECy-AN/NNDPA system was investigated using pyrolysis gas chromatography-mass spectrometry (PY GC-MS). Our results showed that the formation reactions of the intermediate structure and cyclotrimerization reactions occurred during the room-temperature curing process. The activation energies of BECy and different aromatic amine systems at different heating rates were determined using non-isothermal DSC. The results further demonstrated the catalytic effect of AN/NNDPA on the cyanate ester curing reaction. BECy-AN/NNDPA cured at room temperature has suitable heat resistance and a 5% weight loss temperature (Td5) of 361°C.
研究领域:
材料科学
·
化学工程
✓ 已验证
DOI
高影响因子
DRUG DEVELOPMENT AND INDUSTRIAL PHARMACY
·
2020
·
IF 2.365
Jie Liu,Liang Fang,Chao Liu
Objective: This study was to clarify the molecular mechanism of viscoelastic performance variations of pressure-sensitive adhesive (PSA) with the addition of drugs by FT-IR spectroscopy and molecular modeling.Significance: Viscoelastic performance of PSA was frequently changed by the addition of drugs in drug-in-adhesive (DIA) patches. It may cause decrease of the physical stability and drug bio-adhesion issues for the development of DIA patch. But, the molecular details of drug–PSA interaction are not clarified.Methods: Model drugs including propranolol (PRO), oxybutynin (OXY), and escitalopram were added into patch with hydroxyl PSA (10%, w/w). Rheological study and thermal analysis were used to characterize the viscoelastic performance and free volume of PSA, respectively. 1H NMR was used to determine the quantity of hydroxyl group in the PSA. FT-IR study and molecular modeling were conducted to describe the types and interaction sites between drug and PSA molecule.Results: The results demonstrated that PRO interacted with –OH and –COOR groups of PSA, which interrupted the interaction between the PSA molecules, resulting in a plasticizing phenomenon of PSA. Escitalopram mainly interacted with –OH of PSA and decreased the rigidity of the drug-loaded PSA only in the high-frequency region. No obvious interaction was found between OXY and PSA, and the viscoelastic performance of PSA did not change significantly.Conclusion: The present study described the molecular mechanism of viscoelastic performance variation, especially the plasticizing effect. These results were essential for the design and development of transdermal patches from the viewpoint of viscoelastic performance.
研究领域:
药剂学
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材料科学
·
生物医学工程
✓ 已验证
产品关联
DOI
PubMed
高影响因子
JOURNAL OF SOLID STATE CHEMISTRY
·
2021
·
IF 3.498
Yaxin Feng,Guilin Wei,Yi Liu,Wenhong Han,Yan Chen,Runjie Sun,Lin Peng,Meihua Ma,Yu Zhang,Zhentao Zhang,Xirui Lu
The immobilization of iodine waste is a challenge in the field of nuclear waste . In this work, iodine waste (silver-coated silica gel with different iodine loadings) was immobilized at low-sintering temperatures (500, 550, and 600 °C). XRD represented that the crystallized phases of the sintered matrix consist of AgI and B 2 O 3 . The crystallization behavior of boron can be found as the sintering temperature increased from 500 °C to 600 °C. FT-IR results proved that in the process of crystallization, part of the microstructure related to B–O stretching transformed from [BO 4 ] to [BO 3 ] units, which benefits low-temperature iodine waste immobilization due to the bonding energy of [BO 3 ] is higher than that of [BO 4 ]. Our work reveals the B-related microstructure transition in low-temperature immobilization iodine waste.
研究领域:
核废物处理
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材料科学
·
无机化学
·
放射化学
·
环境工程
✓ 已验证
DOI
高影响因子
ACS Omega
·
2022
·
IF 4.132
Prince Kumar Singh,Jagreeti Singh,Tapas Medhi,Aditya Kumar
Diabetes is a group of metabolic disorders characterized by elevated blood sugar levels, leading to many undesirable health consequences. There are many herbal formulations, traditionally used by the Northeast Indian population for disease management. These formulations require scientific validations to optimize their efficacy and increase their popularity. In this study, we attempt to scientifically validate a polyherbal formulation traditionally used for the management of diabetes through preliminary phytochemicals investigation, characterization of potential phytochemicals using Fourier transform infrared (FT-IR) spectroscopy, high-resolution liquid chromatography mass spectrometry (HR-LC/MS) analysis, and in silico characterization of physiochemical, drug-likeness, and pharmacokinetic properties of identified phytochemical compounds. Qualitative phytochemical screening of various extracts of the formulation confirmed the presence of alkaloids, phenols and tannins, flavonoids, fats, and oils. Phytochemical quantification of the various extracts showed that the highest total phenolic content is present in the ethanolic extract (35.61 ± 0.15 mg GAE/g), while the highest total flavonoid content is present in the chloroform extract (76.33 ± 2.96 mg QE/g) of the formulation. FT-IR spectroscopic analysis revealed various characteristic band values with various functional groups in the formulation extract such as amines, alcohol, fluoro compounds, phenol, alkane, alkene, and conjugated acid groups. HR-LC/MS analyses identified nearly 51 compounds including 9 small peptides and 42 potential phytochemical compounds. In silico SwissADME analysis of identified compounds revealed 25 potential compounds following Lipinski’s rule and showing drug-like characteristics, and out of them, 16 compounds exhibited good oral bioavailability, as revealed in the bioavailability radar. The overall study showed that the presented polyherbal formulation is enriched with bio-active phytochemical compounds with good pharmaceutical values.
研究领域:
药理学
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植物化学
·
生物信息学
✓ 已验证
DOI
PubMed
高影响因子
CERAMICS INTERNATIONAL
·
2021
·
IF 4.527
Debao Liu,Baolu Shi,Chenqi Wang,Zeshuai Li,Xianbo Wang,Baosheng Xu,Lijie Qu
Herein, the SiC ceramic aerogels with in-situ growth of SiC nanowires (SiC w /SiC CAs) have been synthesized by polymer‐derived ceramics (PDCs) method. The morphology, microstructure, and phase composition of the as-prepared samples were systematically investigated through SEM, XRD , TEM , Raman spectrum, FT-IR spectrum, and XPS spectrum techniques. The results showed that the as-obtained SiC w has a diameter of about 80 nm and a length of 1–3.5 μm. In addition, the formation mechanism and evolution process of growth SiC w were systematically studied using a VLS growth mechanisms. The way in this work could be expanded to synthesize other Si-based porous ceramic aerogel nanostructed with nanowires.
研究领域:
材料科学
·
纳米技术
·
陶瓷
✓ 已验证
DOI
高影响因子
HYDROMETALLURGY
·
2023
·
IF 4.7
Xintong Li,Yongna Guo,Xin Ma,Chao Zhang,Jia Yang,Shuai Wang
Herein, a series of α -hydroxyalkyl phosphinic acids were designed and first introduced in Mn 2+ extraction and Mn 2+ -Mg 2+ separation. The extraction tests indicate that the α -hydroxy-2-ethylhexyl phosphinic acid ( α -H-2-EHA) possesses superior extraction ability compared to di-2-ethylhexyl phosphinic acid (P204) for Mn 2+ and Mg 2+ , and the partition coefficient ( β ) is 28.2 at a saponification ratio of 30%. The results of quantum chemical calculation, FT-IR spectrum and slope analysis method reveal that the α -H-2-EHA can form stable four-membered ring structure with metal ions during the extraction process through P–OH and P O bonds. Furthermore, the HOMO composition results suggest that α -OH might also promote the interaction between extractant and metal ions. Finally, a three-stage countercurrent extraction—washing—stripping process was proposed and Mn 2+ can be enriched from 11.2 g/L to 36.6 g/L, with Mg 2+ decreased from 30.3 g/L to 0.6 g/L, which provides an efficient strategy for the preparation of high-purity manganese.
研究领域:
化学工程
·
分析化学
·
材料科学
✓ 已验证
产品关联
DOI
高影响因子
JOURNAL OF DISPERSION SCIENCE AND TECHNOLOGY
·
2018
·
IF 1.454
Lujiao Shi,Yi Wei,Nan Luo,Tianwei Tan,Hui Cao
In the present study, cationic xanthan gum (CXG) was synthesized to enhance the rheological property of xanthan gum (XG) by attaching quaternary amine groups to the backbone of XG. The efficacy of the substitution was confirmed by FT-IR spectra and 13C NMR. The surface morphology was changed considerably as demonstrated by SEM. The examined rheological properties of XG and CXG include steady-state and dynamic rheological properties. The results show that quaternary amine groups are successfully grafted onto the XG molecule. Apparent viscosity, storage modulus, and loss modulus of CXG solutions are greater than those of XG solutions under the same conditions. It is moreover found that apparent viscosity and viscoelasticity increase with the degree of substitution. The data indicate that the modified XG has much better heat resistance.
研究领域:
化学工程
·
材料科学
·
流变学
✓ 已验证
产品关联
DOI
高影响因子
Catalysis Science & Technology
·
2023
·Vol. 13
·期 21
·6185-6197
·
IF 5
Hui Guo,Tingting Ge,Yuchao Li,Yuxia Li,Yanxia Zheng,Xinpeng Guo,Haofei Huang,Ming Wang,Cuncun Zuo
Organic solvent method was used to prepare the active component VPO, which was loaded on ball-milled γ-Al2O3 support. VPO/γ-Al2O3 catalysts were synthesized by in situ generation for the synthesis of acrylic acid (AA) by the aldol condensation of acetic acid (HAc) and formaldehyde (HCHO). The effects of the calcination temperature and the loading of the active component VPO on catalytic activity were systematically investigated. XRD, BET, SEM, CO2/NH3-TPD, FT-IR spectroscopy, and TG techniques were used to characterize the VPO/γ-Al2O3 catalysts. The results showed that the catalyst had the best crystal structure and acid–base activity center at a calcination temperature of 350 °C. The catalytic performance was evaluated using a fixed bed reactor. 60% VPO/γ-Al2O3 exhibited the highest reactivity, and the yield of AA was up to 51.5%. Response surface methodology (RAM) was used to optimize the reaction conditions for aldol condensation. The kinetic equation and reaction order of the aldol condensation reaction were determined using the VPO/γ-Al2O3 catalyst. It provides guidance for the in-depth study of aldol condensation reactions in the future.
研究领域:
催化
·
化学工程
·
材料科学
·
物理化学
✓ 已验证
产品关联
DOI
高影响因子
危险品化学品经营许可证（带存储）