Journal of Physical Chemistry C
·
2021
·
IF 4.126
Haoting Zheng,Guojie Xu,Kun Wu,Liang Feng,Rongguang Zhang,Yiliang Bao,Han Wang,Kunxin Wang,Zhencai Qu,Jun Shi
A series of poly(vinylidene fluoride) (PVDF)/poly(vinyl alcohol) (PVA) composite films with different ratios were prepared by electrospinning. Because of the intermolecular interaction force, the highest thermal conductivity of the above film is 2.434 W m–1 K–1, which is about 60% higher than that of the pure PVDF film without a strong intermolecular interaction force. Infrared and wide-angle X-ray diffraction (WXAD) proved that PVDF as a thermal bridge enhances the internal interaction force and makes the internal structure more regular. The laser method shows that the film with strong intermolecular interaction has higher thermal diffusivity. Using molecular dynamics to explore the thermal expansion rate of the system, it is found that the intermolecular interaction force and the thermal bridge can effectively inhibit the activity of the molecular chain and reduce its free volume. After an in-depth study of the influence of the intermolecular interaction force and the thermal bridge on polymers, it is found that electrospinning can conveniently and effectively improve the ordering of the polymer structure. Integration of the electrospinning method and intermolecular interaction leads to the remarkable improvement of intrinsic thermal conductivity for polymer blends.
研究领域:
材料科学
·
热传导研究
✓ 已验证
DOI
高影响因子
Nanomaterials
·
2022
·Vol. 12
·期 5
·797
·
IF 5.719
Feipeng Wang,Zheng Zhang,Yuyang Yan,Zijia Shen,Qiang Wang,Reimund Gerhard
Tailoring the secondary surface morphology of electro-spun nanofibers has been highly desired, as such delicate structures equip nanofibers with distinct functions. Here, we report a simple strategy to directly reconstruct the surface of polyvinyl alcohol/polyvinylpyrrolidone (PVA/PVP) nanofibers by water evaporation. The roughness and diameter of the nanofibers depend on the temperature during vacuum drying. Surface changes of the nanofibers from smooth to rough were observed at 55 °C, with a significant drop in nanofiber diameter. We attribute the formation of the secondary surface morphology to the intermolecular forces in the water vapor, including capillary and the compression forces, on the basis of the results from the Fourier-transform infrared (FTIR) and X-ray photoelectron (XPS) spectroscopy. The strategy is universally effective for various electro-spun polymer nanofibers, thus opening up avenues toward more detailed and sophisticated structure design and implementation for nanofibers.Keywords:surface reconstruction;intermolecular force;surface-roughened nanofiber
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 APPLIED POLYMER SCIENCE
·
2021
·Vol. 139
·期 10
·51639
·
IF 3.125
Haixiang Hu,Yu Qiu,Zheng Lu,Chuxuan Tang,Hailin Yao,Ming Cheng
The logical coherence macro–micro experiments about the anti-swelling performance of polyetheramine-230 (PEA-230) on expansive natural soil are presented in this paper. Further, the expansion of the soil in the solution and water system is considered. Great significance in treating the expansive soil broadens the applied range of polyetheramine-230. The mechanism is assessed by X-ray diffraction (XRD) in the state of wet and dry montmorillonite (Mt), XRD of dry clay extracts from the soil, zeta potential measurement, thermogravimetric analysis, and scanning electron microscopy. The results prove the significant effect of controlling the expansion of expansive soil. PEA-230 strongly adsorbs on the surface of soil particles and intercalates into the layer structure. Further, the PEA-230/soil hybrids can be judged as usable engineering soil with low expansion characteristics. Additionally, the concentration of PEA-230 controls the treatment effect, and 1 wt% PEA-230 is a proper concentration to treat the expansive soil. In particular, PEA-230 has excellent characteristics such as small molecular weight, good water solubility, and good stability. Thus PEA-230 can be regarded as a great agent to treat in-situ expansive soil.
研究领域:
土木工程
·
材料科学
·
地质学
✓ 已验证
DOI
高影响因子
MACROMOLECULES
·
2017
·
IF 5.835
Zhixiang Cai,Fei Zhang,Yue Wei,Hongbin Zhang
Physically cross-linked hydrogels from hyaluronan (hyaluronic acid, HA) were prepared by a freeze–thaw technique at low pH. The effect of the freezing–thawing of HA solutions on the formation of physical cryogels is typical for the processes of noncovalent cryostructuration that takes the advantages of mild fabrication conditions and the absence of organic solvents and toxically cross-linking agents. The effects of processing steps (freezing time and number of freeze–thaw cycles), HA molecular weight (Mw), and the addition of typical polycarboxylic and polyhydric small molecules such as dicarboxylic acids and polyols on the formation of HA cryotropic hydrogels were investigated. Results verified that long freezing time and repeated freeze–thaw cycles benefited the alignment of polymer chains in the unfrozen liquid microphase, thereby promoting the formation of intermolecular aggregations and dense fibrillar network structures. High Mw of HA endowed the cryogel with strong mechanical strength. The influences of various small molecules on the cryogelation of HA revealed the different intermolecular association patterns in the gel network. Both succinic and glutaric acids participated in HA cryogelation, whereas oxalic, malic, and tartaric acids as well as some polyols (glycol, butanediol, and glycerol) inhibited the cryostructuration of HA. Hydrogen bonding and intermolecular interactions in acidic cryogels and in neutral cryogels obtained by in situ neutralizing the acidic cryogel were discussed at the molecular level in correlation with intermolecular associations and molecular conformation. A gelation mechanism for HA cryogel was proposed. In addition, experimental findings showed that the neutral HA cryogels possessed enhanced thermostability, resistance to acid decomposition, and enzyme degradation which are essentially important properties for biomaterials.
研究领域:
生物材料学
·
高分子化学
·
药剂学
✓ 已验证
DOI
高影响因子
Frontiers in Plant Science
·
2023
·
IF 5.6
Pengfei Deng,Ruoyong Yin,Huiling Wang,Leiru Chen,Xiaoqing Cao,Xiaoniu Xu
The intercropping practice has been regarded as a practical land-use selection to improve the management benefits of Bletilla striata plantations. The reports about the variety of economic and functional traits of Bletilla pseudobulb under intercropping systems were limited. The present study investigated the variation of economic and functional traits of Bletilla pseudobulb under different intercropping systems (the deep-rooted intercropping system: B. striata - Cyclocarya paliurus, CB; and the shallow-rooted intercropping system: B. striata - Phyllostachys edulis, PB). The functional traits were analyzed through non-targeted metabolomics based on GC-MS. The results indicated that the PB intercropping system significantly decreased the yield of Bletilla pseudobulb while significantly increasing the total phenol and flavonoids compared with the control (CK). However, there were no significant differences in all economic traits between CB and CK. The functional traits among CB, PB, and CK were separated and exhibited significant differences. Under different intercropping systems, B. striata may adopt different functional strategies in response to interspecific competition. The functional node metabolites (D-galactose, cellobiose, raffinose, D-fructose, maltose, and D-ribose) were up-regulated in CB, while the functional node metabolites (L-valine, L-leucine, L-isoleucine, methionine, L-lysine, serine, D-glucose, cellobiose, trehalose, maltose, D-ribose, palatinose, raffinose, xylobiose, L-rhamnose, melezitose, and maltotriose) were up-regulated in PB. The correlation between economic and functional traits depends on the degree of environmental stress. Artificial neural network models (ANNs) accurately predicted the variation in economic traits via the combination of functional node metabolites in PB. The correlation analysis of environmental factors indicated that Ns (including TN, NH4+-, and NO3--), SRI (solar radiation intensity), and SOC were the main factors that affected the economic traits (yield, total phenol, and total flavonoids). TN, SRI, and SOC were the main factors affecting the functional traits of the Bletilla pseudobulb. These findings strengthen our understanding of the variation of economic and functional traits of Bletilla pseudobulb under intercropping and clarify the main limiting environmental factors under B. striata intercropping systems.
研究领域:
植物学
·
药用植物学
·
生态学
✓ 已验证
DOI
高影响因子
JOURNAL OF CHEMICAL AND ENGINEERING DATA
·
2022
·
IF 3.119
Li Chen,Lingbin Shen,Yuhang Chen,Zhengyang Luo,Zexin Ren,Rongrong Li,Cunbin Du
The solubility data of nimesulide (form I) in different mono- and mixed solvents over the temperature range from 273.15 to 318.15 K are determined. In this work, it is further studied to improve the solubility data of nimesulide (form I) and analyze the intermolecular force. The solubility profiles in mono- and mixed solvents are correlated by some thermodynamic models. The results of statistical analysis show that all selected models could provide a good correlation of the dissolution profile for nimesulide in selected solvents at all investigated temperatures. At 318.15 K, the largest solubility in mole fraction is obtained in acetone (7.812 × 10–2), followed by 2-butanone (6.334 × 10–2), cyclohexanone (4.977 × 10–2), ethyl acetate (3.803 × 10–2), tetrahydrofuran (3.651 × 10–2), acetonitrile (2.975 × 10–2), ethanol (2.169 × 10–3), toluene (1.788 × 10–3), isobutanol (1.348 × 10–3), isopropanol (1.201 × 10–3), and propylene glycol (PG, 6.764 × 10–4). However, in mixtures of (ethyl acetate + isopropanol), the solubility data increase with the increase of the mass fraction of ethyl acetate at a given temperature. The effect of solute–solvent interactions on the solid–liquid phase equilibrium of the solute is discussed with the solvent properties. The calculation of preferential solvation parameters shows that solute molecules are preferentially solvated by isopropanol in isopropanol-rich regions and as the mass fraction of ethyl acetate increases, nimesulide is preferentially solvated by ethyl acetate. Studying the dissolution process of nimesulide is of great practical significance for its purification.
研究领域:
药学
·
物理化学
✓ 已验证
DOI
高影响因子
FOOD CHEMISTRY
·
2023
·
IF 8.8
Qing-Ru Liu,Xian-Li Lin,Zhen-Ming Lu,Li-Juan Chai,Song-Tao Wang,Jin-Song Shi,Su-Yi Zhang,Cai-Hong Shen,Xiao-Juan Zhang,Zheng-Hong Xu
Long-chain fatty acids (LCFAs) are commonly presented in Baijiu, but their influence on flavor is ambiguous. The interaction between LCFAs and volatiles was systematically investigated in terms of chemometrics, sensory, and chemical-physical perceptions. The static-headspace-gas-chromatography-mass-spectrometry results demonstrated LCFAs suppressed the volatilizations of most volatiles. According to Phase-ratio-variation analysis, partition coefficients of ethyl acetate (EA) and ethyl hexanoate (EH) decreased 4%–31% and 27%–74%, while those of ethyl butyrate (EB) increased. Calculated by molecular dynamic simulation, the attractive intermolecular forces related to EA/EH increased with oleic acid (OA) addition, while those related to EB decreased. Sensory evaluation confirmed the olfactory threshold of EA and EH increased by 2.4 and 2.7 times respectively, but the threshold of EB decreased from 0.36 to 0.05 mg/L in the presence of OA. Overall, LCFAs altered the intermolecular interaction forces related to esters and ethanol, subsequently affecting the volatile profile and modifying Baijiu flavor's sensory perception.
研究领域:
食品科学
·
化学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
JOURNAL OF MOLECULAR LIQUIDS
·
2024
·
IF 5.3
Jialu Bo,Baoli Shi
Obtaining the interaction between two substances in liquid through their molecular structures can promote the design and preparation of new functional materials. When multiple types of intermolecular forces coexist, whether the contribution terms generated by each type of intermolecular force have the same scaling factor is a key consideration. In this paper, an empirical equation for calculating the total intermolecular interaction is proposed. The required molecular property parameters for calculation can be obtained through quantum–chemical calculation. For the experiments of removing eight ionic dyes in water by using corn cobs as adsorbents, linear correlation was found between the removal percentage and the total interaction calculated from the proposed equation. When the scaling factors of polar and hydrogen bond interaction terms are 1, the scaling factor of dispersion force interaction term in the equation is greater than 2.5.
研究领域:
化学
·
材料科学
✓ 已验证
产品关联
DOI
高影响因子
INTERNATIONAL JOURNAL OF BIOLOGICAL MACROMOLECULES
·
2023
·
IF 8.2
Peng Zhou,Min Zheng,Xiangzhou Li,Jun Zhou,Wensheng Li,Yanhong Yang
It is an appropriate strategy to construct the carrier material with polysaccharide pectin, which is the characteristics of good bio-compatible, safe and non-toxic, avoiding the functional loss of bioactive ingredients and achieve sustained release . However, the loading mechanism of the active ingredient and the release behaviour of the active ingredient from the carrier material is still at the stage of conjecture. In this study, a kind of synephrine-loaded calcium pectinate beads (SCPB) with high encapsulation efficiency (95.6 %), loading capacity (11.5 %) and excellent controlled release behaviour was constructed. The interaction between synephrine (SYN) and quaternary ammonium fructus aurantii immaturus pectin (QFAIP) was revealed by FTIR, NMR and density functional theory (DFT) calculation. An inter-molecular hydrogen bond and Van der Waals forces between 7-OH, 11-OH and 10-NH of SYN and -OH, -C=O and N + (CH 3 ) 3 of QFAIP were formed. The release experiment in vitro showed that the QFAIP could effectively avoid the release of SYN in gastric fluid, and also realized the slow and full release of SYN in intestinal tract. Moreover, the release mechanism of SCPB in simulated gastric fluid (SGF) was Fickian diffusion, while in simulated intestinal fluid (SIF) was a non-Fickian diffusion controlled by both diffusion and skeleton dissolution.
研究领域:
药剂学
·
食品科学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
Journal of Integrative Agriculture
·
2024
·
IF 4.6
Jie Li,Shanjie Han,Ruhang Xu,Xuchen Zhang,Junquan Liang,Mengxin Wang,Baoyu Han
Phthalate esters (PAEs) are an emerging pollutant due to widespread distribution in environmental mediums that have attracted widespread attention over recent years. However, there is little information about tea plantation soil PAEs. A total of 270 soil samples collected from 45 tea plantations in the major high-quality tea-producing regions of Jiangsu, Zhejiang, and Anhui provinces in China were analyzed for seven PAEs. The detection frequency of PAEs in tea plantation soil was 100%. DBP, DEHP, and DiBP were the main congeners in tea plantation soil. The PAEs concentrations in the upper soil were significantly higher than those in the lower soil. The concentration of tea plantation soil PAEs in Jiangsu Province was significantly lower than those in Zhejiang and Anhui provinces. Intercropping with chestnuts can effectively reduce the contamination level of PAEs in tea plantation soil. Correlation analysis, redundancy analysis, partial correlation analysis, and SEM methods further confirmed the strong direct influence of factors such as chestnut-tea intercropping, temperature, and agricultural chemicals on the variation of PAEs in tea plantation soil. The health and ecological risk assessments indicated that non-carcinogenic risk was within a safe range and that there was a high carcinogenic risk via the dietary pathway, with DBP posing the highest ecological risk.
研究领域:
环境科学
·
毒理学
✓ 已验证
产品关联
DOI
高影响因子
COLLOIDS AND SURFACES A-PHYSICOCHEMICAL AND ENGINEERING ASPECTS
·
2025
·
IF 5.4
Xuejuan Cao,Shangyi Rao,Zuoyang Cheng,Zefeng Wu,Ying Yuan
At present, there have been many research results on the relationship between the microscopic and macroscopic properties of asphalt from the perspective of asphalt chemical composition and microstructure. However, asphalt is a colloidal material that exists in an aggregated form. In addition to its chemical composition and microstructure, its intermolecular forces will also greatly affect the performance of asphalt.In order to understand the connection between the rheological properties of asphalt and the forces between asphalt molecules, this study used two chemical modification methods, methylation, and carboxylation, to change the interaction strength between asphalt molecules and explore the impact of chemical modifications on the rheological properties of asphalt. Fourier transform infrared spectroscopy analysis showed that the modified asphalt had been successfully prepared, and frequency scanning was performed at different temperatures with the help of a dynamic shear rheometer to construct the master curve. The results showed that the elasticity of methylated asphalt was negatively related to the degree of methylation, and the opposite was true for viscosity; The elasticity of carboxylated asphalt initially increased and then decreased as the carboxylation degree increased, and the opposite was true for viscosity. In addition, the influence of chemical modification on the volume fraction of the dispersed phase in asphalt was investigated. It was observed that methylation of asphaltene weakened the hydrogen bonding, increased the distance between asphaltene molecules, and resulted in the reaggregation of asphaltene. Colloids with large particle sizes were removed, and the volume fraction of the dispersed phase decreased as the degree of methylation increased, resulting in a decrease in asphalt elasticity. After carboxylation modification, the hydrogen bonding between asphalts was enhanced. In the early stage, the colloidal particle size was reduced, the volume fraction of the dispersed phase was increased, and the elasticity of the asphalt was improved. When the carboxylation reached a certain level, the asphaltene molecules were further associated with each other, and the original content in the system was reduced. Some colloids also tended to aggregate with each other, the colloid particle size became larger, the volume fraction of the dispersed phase decreased, and the asphalt elasticity decreased.
研究领域:
材料科学
·
化学工程
✓ 已验证
产品关联
DOI
高影响因子
FOOD CHEMISTRY
·
2019
·
IF 5.399
Na Sun,Yixing Wang,Zhijie Bao,Pengbo Cui,Shan Wang,Songyi Lin
Phosphorylation could improve functional characteristics of proteins/peptides, and might be used in the functional improvement of herring egg peptides owing to their enriched phosphorylation sites. The present study aimed to study the effect of phosphorylation on calcium-binding ability of herring egg peptides, and investigate the conformational structure and intermolecular forces of herring egg phosphopeptides (HEPPs)-calcium complex. The HEPPs were found to be superior in calcium-binding activities, as compared to the non-phosphorylated variant. This finding might be attributed to the interaction between calcium ions and the introduced phosphate groups of HEPPs. Calcium favored the formation of β-sheet structure on the HEPPs and induced structural folding, thus assembling into spherical nanoparticles. The conformation of HEPPs-Ca nanoparticles was formed and stabilized mainly by hydrophobic interaction, hydrogen bonds and electrostatic interaction.
研究领域:
食品科学
·
生物化学
✓ 已验证
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）