POWDER TECHNOLOGY
·
2019
·
IF 3.413
Yaowen Xing,Youfei Zhang,Shihao Ding,Xi Zheng,Mengdi Xu,Yijun Cao,Xiahui Gui
Surface roughness plays a critical role in flotation , as it has a marked impact on bubble-particle interaction, i.e., attachment and detachment. In the present study, the effect of surface roughness on the detachment between bubble and glass beads with different contact angles was investigated using a home-built system for measuring bubble-particle detachment. By applying a simple harmonic oscillation to a bubble-particle aggregate, the critical detachment force could be calculated from the critical amplitude based on Newton's second law. Smooth and rough glass beads were hydrophobized simultaneously using octadecyl trichlorosilane vapor to ensure that they have the same local contact angle in parallel experiments. The results show that the detachment force of a smooth particle was higher than that of a rough particle when the local contact angle with the particle surface was below 90° (hydrophilic). However, the detachment force of a rough particle was higher than that of a smooth particle when the local contact angle was above 90° (hydrophobic). Surface roughness rendered the hydrophilic bubble-particle aggregate less stable while hydrophobic bubble-particle aggregate more stable. The decrease in apparent contact angle and contact line length decreased the detachment force of the hydrophilic particles, while an increase in these parameters increased the detachment force of the hydrophobic particles.
研究领域:
材料科学
·
化学工程
·
表面化学
✓ 已验证
产品关联
DOI
高影响因子
FOOD RESEARCH INTERNATIONAL
·
2024
·
IF 7
Jin Du,Yajing Qi,Alkassoumi Hassane Hamadou,Jian-Ya Qian,Bin Xu
The objective of this research was to investigate the influence of starch granule-associated lipids (SGALs) on retrogradation properties of buckwheat and wheat starches. According to the results, the removal of SGALs led to remarkable increase in the retrogradation enthalpy change of all starches and the strength of starch gels, as well as the density and short-range ordered structure of starch aggregates. The strength of starch gel experienced a rise from 3139.39 g to 3718.18 g in Tartary buckwheat, 2924.12 g to 3551.13 g in common buckwheat, and 1887.55 g to 2555.24 g in wheat, respectively. The removal of SGALs contributed to a decrease in the thermal stability of starches and an augmentation of amylose leaching during gelatinization process, which would strengthen the hydrogen bond interaction between starch molecules during cooling process, and promoting the rearrangement of the order structure of starch molecules. In general, these results indicated that the retention of SGALs could limit amylose leaching, then inhibited rearrangement and recrystallization of dissolved starch molecules, and ultimately delayed the short-term and long-term retrogradation process. This work further supplemented theoretical knowledge about SGALs in buckwheat and wheat starches, also provided a new perspective for regulating the physicochemical properties of starches.
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
ATMOSPHERIC ENVIRONMENT
·
2022
·
IF 5.755
Jixing Liu,Shuping Zhu,Teng Guo,Bin Jia,Li Xu,Jun Chen,Ping Cheng
Naphthalene (Nap), one of the most abundant PAHs in the atmosphere, has been shown to be an important secondary organic aerosol (SOA) precursor. In this study, the gas- and particle-phases (Suspended Nap-coated polystyrene latex spheres (PSLs) generated by vaporization condensation) Nap ozonolysis were investigated in a 1000 L volume cubic Teflon smog chamber. Gas-phase products and Nap-SOAs were observed from the gas- and particle-phase Nap ozonolysis via homogeneous and heterogeneous reactions, respectively. The time-dependent size distribution and mass concentration of Nap-SOAs were analyzed using a scanning mobility particle sizer and a laboratory-developed single-particle aerosol mass spectrometry (SPAMS) instrument. The chemical components of the homogeneous and heterogeneous reaction products were analyzed on-line by single photo ionization mass spectrometry (SPIMS), SPAMS, as well as by thermal desorption gas chromatograph-mass spectrometry. The results showed that the chemical components of the gas-and particle-phase Nap ozonolysis were essentially the same, with the dominant products being phthalaldehyde, phthalic anhydride, 2-carboxybenzaldehyde, and benzoic acid ; Nap-SOA formation was attributed to the formation of new particles as well as the uptake of homogeneous and heterogeneous Nap oxidation products on the gas-phase or/and the particle surface. Based on the online measurement results, the reaction mechanism of Nap-ozonolysis also exhibits an initial carbon atom or double-bond attacks by O 3 , and kinetic analysis of Nap-coated PSLs ozonolysis shows a heterogeneous reaction rate constant of 2.55E-4 s −1 with R 2 = 0.984. This study provides a systematic approach to characterize the chemical and physical properties of the gas- and particle-phase Nap ozonolysis in real time, which will deepen our understanding of the migration and transformation of PAHs in the atmosphere.
研究领域:
大气化学
·
环境科学
✓ 已验证
产品关联
DOI
高影响因子
COLLOIDS AND SURFACES A-PHYSICOCHEMICAL AND ENGINEERING ASPECTS
·
2020
·
IF 3.99
Zhanglei Zhu,Wanzhong Yin,Huili Han,Shaohang Cao,Bin Yang,Donghui Wang
It is well known that surface roughness of mineral particles has a significant influence on their flotation behaviors. In this investigation, magnetite was ground in rod and ball mills to generate particles with similar dimension and shape but varying degree of surface roughness, which was quantified using Atomic Force Microscopy (AFM). The influence of surface roughness on the floatability of magnetite particles was performed by flotation tests using an XFG flotation machine. Flotation tests indicated magnetite particles possessed higher surface roughness had higher flotation recovery and larger flotation rate constant. The aggregation behaviors of different rough magnetite particles were compared for the first time via an optical microscopy. Results of the optical microscopic tests revealed that there were a large number of aggregations in the system of particles with higher surface roughness. A proposed model was deduced with the parameters carefully calculated (not arbitrarily selected) to analyze the bubble-particle interaction energy using an Extended DVLO (Derjaguin–Landau–Verwey–Overbeek) theory. The theoretical interaction energy points to lowering energy barrier when magnetite particles are covered with 28.03 nm asperities as compared to 9.47 nm asperities. The effect of surface roughness on mineral flotation was investigated from the view of both particle aggregations and energy barrier of bubble-particle attachment for the first time, which are the primary causes for differences in flotation performance.
研究领域:
矿物加工工程
·
界面化学
✓ 已验证
产品关联
DOI
高影响因子
JOURNAL OF MAGNETISM AND MAGNETIC MATERIALS
·
2018
·
IF 3.046
Fang-Hao Niu,Zhi-De Hu,Hua Yan,Jian-Jian Yang,Han-Song Zhang
This work reports an investigation into the redispersibility of magnetorheological suspensions (MR suspensions) by testing the rheological properties of suspension sediment. By using a new freeze-sampling method, slices of sediment were taken from the bottom of the container with little changes on shear history which makes it possible to employ rheological measurement. Size distribution of particles contained in sediment was studied by a laser scattering method. Oscillatory and steady shear was employed to studying the rheological viscoelastic and flow behavior. Also, thixotropy and recovery behavior was also studied. The results obtained proved that redispersibility is a multifactor-dependent property which can be reflected from rheological responses of MR suspensions’ sediment. Hydrodynamic force and particle interaction which have significant influence on those properties were analyzed in this study. In addition, indexes correspond to different rheological properties were put forward to make a comparison quantitatively between traditional MR suspensions.
研究领域:
材料科学
·
流变学
✓ 已验证
产品关联
DOI
高影响因子
MINERALS ENGINEERING
·
2020
·
IF 3.795
Zhanglei Zhu,Donghui Wang,Bin Yang,Wanzhong Yin,Morteza S. Ardakani,Jin Yao,Jaroslaw W. Drelich
Roughness of mineral particles affects bubble-particle interactions and particle flotation separation. In this study, magnesite was ground in stainless-steel disc and ceramic ball mills to produce flotation feed material of different surface nano-roughness, which was quantified using atomic force microscopy (AFM). The effect of surface roughness on the floatability of magnesite particles was carried out by a micro-flotation kinetic test using an XFG flotation machine. The flotation results demonstrated both higher flotation recovery and larger flotation rate constant for particles having larger nano-asperities of rough particle surface. Additionally, the difference in cumulative flotation recovery between magnesite particles with different nano-roughness characteristics systematically decreased with increasing collector (sodium oleate) concentration from 25 to 150 mg/L. Contrarily, a difference in the value of flotation kinetics constant for particles with larger and smaller asperities remained at a level of 0.2–0.3 min −1 for the entire range of collector concentration. The interaction energy between bubbles and rough magnesite particles with different nano-roughness was estimated using an extended DLVO (Derjaguin–Landau–Verwey–Overbeek) theory. The theoretical interaction energy points to lowering energy barrier when the magnesite particles are covered with 12 nm asperities as compared to 2 nm asperities. It is therefore hypothesized that the energy barrier is a primary cause for differences in flotation performance of particles decorated with nano-asperities of different dimensions.
研究领域:
矿物加工工程
·
界面化学
✓ 已验证
产品关联
DOI
高影响因子
CARBOHYDRATE POLYMERS
·
2023
·
IF 11.2
Tianming Yao,Zekun Xu,Mengting Ma,Yadi Wen,Xiaoning Liu,Zhongquan Sui
Starch granule associated lipids (GALs) are known to alter the properties and functions of small granule starches. To test the hypothesis that the removal GALs from small granule starches could increase the overall reactive surface and improve octenyl-succinylation (OSA) modification efficiency, four small granules starches from rice, oat, quinoa, amaranth and a waxy maize starch were subjected to defat, OSA esterification and combined defatted and OSA treatment. The combined treatment showed a significant improvement in the degree of substitution for all starches from both tritration and 1 H NMR methodologies. Confocal microscopy revealed a more uniform distribution of OSA groups on the starch surface. After GALs removal, the bimodal granule size distribution was diminished but reappeared during OSA modification. Pasting viscosity increased for the OSA and GALs removed quinoa, waxy maize and amaranth starches , but it decreased on modified rice and oat starches . OSA treatment alone significantly altered the gelling and rheological properties towards a more soft and less stable starch structure. The combined treatment compensated these changes to some extent and filled the property gap between the native and OSA modified starches . This study demonstrated that removing GALs can achieve more profound OSA derivatization .
研究领域:
食品科学
·
生物化学
✓ 已验证
DOI
PubMed
高影响因子
Royal Society Open Science
·
2019
·Vol. 6
·期 2
·
IF 2.515
Xiu Chen,Quan Shi,Xibin Zhou,Xuezheng Liu
Aldehydes and ketones (AKs) in cigarette smoke are risk to humans and environment. Due to the complexity of itself and the interference of the smoke tar matrix, the aldehydes and ketones in particle phase (AKPs) of mainstream smoke (MSS) and sidestream smoke (SSS) have not been well investigated. In this study, the AKPs of MSS and SSS were derivatized into polar products by reaction with Girard T reagent. The derivatives were isolated rapidly by column chromatography and analysed by Fourier transform ion cyclotron resonance mass spectrometry (FT-ICR MS). Fifteen species of aldehydes and ketones were detected by positive ion electrospray ionization (ESI) FT-ICR MS: O1–6, N1O1–4, N2O1–3 and N3O2–3. The total number of AKPs obtained by ESI FT-ICR MS in MSS and SSS is about 1100 and 970, respectively. After hydrolysis, the original AKPs were obtained and 63 carbonyls were identified and quantified by gas chromatography–mass spectrometry (GCMS). The nitrogen-containing and high-oxygen AKPs were further characterized by Orbitrap mass spectrometry. Structures of compounds with high relative abundance in the mass spectrum were speculated (e.g. a series of degradants of cembrenediol) by comparison with the results of GCMS.
研究领域:
化学
·
环境科学
·
公共卫生
✓ 已验证
产品关联
DOI
PubMed
高影响因子
APPLIED SURFACE SCIENCE
·
2021
·
IF 6.707
Fanfan Zhang,Haichang Yang,Xiahui Gui,Han Guo,Yijun Cao,Yaowen Xing
To develop interfacial nanobubbles (INBs) into application fields, it is of great significance to understand the properties of INBs and their effect on the interaction of inter-particles. In this paper, the morphology of INBs on different hydrophobic surfaces was researched by total internal reflection fluorescence microscopy (TIRF) and atomic force microscope (AFM). A hydrophobic AFM colloid cantilever was used to measure the interaction of inter-particles in the absence and presence of INBs. The results confirm that the formation of INBs is closely related to the hydrophobicity of substrates, more large INBs form on the strong hydrophobic surface (SS). Furthermore, the magnitude and range of the hydrophobic interaction force are positive related to the dimension of INBs. Besides, multiple approaches of hydrophobic colloid to SS, the hydrophobic interaction is further enhanced due to the merging and cavitation of INBs. Therefore, the results presented here provide the relationship between INBs formation and surface hydrophobicity , as well as the effect of INBs on particles interaction. The formation of INBs should be responsible for the hydrophobic interaction of inter-particles, which is a basic insight into the hydrophobic interaction between particles.
研究领域:
物理化学
·
表面科学
·
胶体科学
✓ 已验证
DOI
高影响因子
LANGMUIR
·
2020
·
IF 3.557
Shihao Ding,Yaowen Xing,Xi Zheng,Youfei Zhang,Yijun Cao,Xiahui Gui
It is well recognized that an improved flotation recovery can be achieved by introducing nanobubbles to common flotation practice due to the increased capture efficiency between bubbles and particles. However, the specific role of nanobubbles in bubble-particle interactions (collision, attachment, and detachment) is not well understood. In the present study, we explore the role of surface nanobubbles in bubble-particle detachment. Surface nanobubbles were introduced via ethanol–water exchange and their presence was confirmed using laser scanning confocal microscopy (LSCM). The effect of surface nanobubbles on bubble-particle detachment behavior was then investigated using an oscillating bubble apparatus. Bubble-particle aggregate stability was evaluated using critical detachment amplitude. Further, bubble-particle detachment forces in the absence and presence of nanobubbles were measured directly using a micro-nano mechanical testing system. Using LSCM, numerous surface nanobubbles were observed on a glass surface after ethanol–water exchange, regardless of wettability. The number and lateral dimensions of generated nanobubbles on the hydrophilic surface were significantly smaller than that on the hydrophobic surface. Surface nanobubbles increased the stability of bubble-particle aggregates. Macroscopic air bubbles coalesce with the nanobubbles on the particle surface, increasing the pinning effect of the three-phase contact line and advancing contact angle. As a result, the capillary force between bubbles and particles increased in the presence of surface nanobubbles.
研究领域:
矿物加工工程
·
界面科学
·
材料科学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
MINERALS ENGINEERING
·
2025
·
IF 5
Tengyue Yuan,Yao Guo,Chao Su,Zhiyuan Wang,Aiyan Zuo,Longhua Xu,Jia Tian,Zhoujie Wang,Kaiqian Shu,Donghui Wang,Kai Xue,Yue Cao
Flotation is a technology that utilizes the differences in hydrophobicity of mineral surfaces to selectively adsorb mineral particles onto bubble surfaces. While traditional research predominantly focuses on mineral-reagent adsorption mechanisms, the role of the foam phase in the flotation process remains insufficiently investigated, particularly in mixed collector systems. In this study, the flotation performance of spodumene with different particle sizes in the NaOL/DDA mixed system was investigated from the perspective of foam properties. Flotation experiments on spodumene with different particle sizes demonstrated higher recovery for intermediate particle size; however, the adsorption heat and adsorption capacity of the agents on the surface of its mineral particles are not the highest. This suggests that the flotation performance of minerals with different particle sizes cannot be fully explained by reagent adsorption mechanisms alone. The results of two-phase foam properties analysis revealed that increasing the DDA proportion in the NaOL/DDA mixed system progressively decreased foaming capacity and foam stability. The results of three-phase foam properties analysis demonstrated that intermediate particle size resulted in significantly enhanced foam stability, consistent with observed flotation performance trends. Through zeta potential measurements, optical microscopy observations, and viscosity measurements, the mechanism of foam stability was studied. It was found that the distribution of surface charges on the bubbles regulated the stability of the foams. Electrostatic interactions not only control the flow rate of the liquid layer, but also indirectly regulate the adhesion of particles and bubbles, thereby affecting the flotation effect of minerals. This investigation provides a novel perspective on interpreting flotation phenomena in mixed collector systems.
研究领域:
矿物加工工程
·
界面与胶体化学
·
资源与环境科学
·
浮选药剂作用机制
·
过程强化与分离技术
✓ 已验证
产品关联
DOI
高影响因子
COLLOIDS AND SURFACES A-PHYSICOCHEMICAL AND ENGINEERING ASPECTS
·
2014
·
IF 2.354
Yonghai Song,Mei Huang,Dan Luo,Dandan Zhong,Haoqing Hou,Fugang Xu
In this study, we investigated the interaction between EcoRI and CdS QDs modified with different functional groups as well as the conformational changes of EcoRI in the process. MUD capped (CdS–OH QDs) and UDT capped (CdS–CH 3 QDs) CdS QDs were separately prepared and used to react with EcoRI, respectively. The interaction was characterized by various spectroscopic techniques including UV–vis absorption, fluorescence and Fourier transform infrared (FTIR) spectroscopy, together with electrophoresis methods. The strength of interaction for EcoRI with CdS–OH QDs and CdS–CH 3 QDs was evaluated and analysed. Relevant thermodynamic parameters such as Δ H , Δ G and Δ S were calculated and a static quenching interaction process was proposed. The conformational change of EcoRI interacted with CdS–OH QDs or CdS–CH 3 QDs was also measured and compared. Finally agarose electrophoresis assay was performed and revealed that the enzyme activity of EcoRI was somewhat conserved after interaction with CdS QDs. This study contributed to a better understanding of protein-NPs interaction and created a framework for applications of nanomaterial-biomolecule conjugation in some fields such as nanobiology and nanomedicine.
研究领域:
纳米生物技术
·
生物化学
·
分子生物学
·
纳米医学
✓ 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）