MICROCHIMICA ACTA
·
2019
·Vol. 186
·期 12
·1-8
·
IF 5.479
Li Te,Xie Lianwu,Long Ruiqing,Tong Chaoying,Guo Ying,Tong Xia,Shi Shuyun,Lin Qinlu
Red-emissive carbon dots (CDs) were synthesized by one-step hydrothermal technique using citric acid (CA), and urea in N , N -dimethylformamide (DMF) solution. The CDs has an average diameter of 2.3 nm, excitation/emission maxima at 553/606 nm, and a low photoluminescence quantum yield (4%). Fluorescence is weakly quenched by the ions Fe 3+ , Hg 2+ , Cu 2+ , Co 2+ , Zn 2+ , Ca 2+ , Ni 2+ , and Pb 2+ . After addition of cetyltrimethyl ammonium ion (CTAB), electrostatic interaction between negatively charged CDs and CTAB causes the CDs to self-aggregate. The formation of CD/CTAB increases the average particle diameter to around 13 nm and enhances the quantum yield to 24%. The hydrophobic segments of CTAB twined into a network structure can selectively trap Fe 3+ and then interact with surface groups of the CDs to cause quenching. The CD/CTAB nanoprobe enables fluorometric determination of Fe 3+ with a linear response in the 0.10–10 μM concentration range and a 0.03 μM limit of detection. The probe was utilized for determination of Fe 3+ in human serum samples, and satisfactory results were obtained.
Schematic representation of fluorometric analysis of Fe(III) ion by cetyltrimethyl ammonium ion (CTAB) mediated red emission carbon dots (CDs). The hydrophobic segments of CTAB twined into a network structure can selectively trap Fe(III) and then interact with surface groups of the CDs to cause quenching.
研究领域:
分析化学
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材料科学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
ACS Applied Nano Materials
·
2019
·
IF 0
Fei Luo,Dongya Wang,Jindong Zhang,Xiaona Li,Dongmei Liu,Hai Li,Min Lu,Xiaoji Xie,Ling Huang,Wei Huang
Preparing few-layer black phosphorus flakes, in a scalable, fast, and benign way, is a key step to promote both the fundamental research and practical applications of black phosphorus. Although the electrochemically assisted liquid exfoliation of bulk black phosphorus is a promising strategy, it is still challenging to obtain few-layer black phosphorus flakes in polar protic solvent through cathodic exfoliation. In this work, we demonstrate an ultrafast approach to exfoliate bulk black phosphorus, under a cathodic potential, in an aqueous solution of hexadecyltrimethylammonium chloride. Particularly, the exfoliation can be trigged within ∼20 s, and the obtained flakes exhibit satisfactory quality. Further detailed mechanical explorations reveal that the cathodic intercalation of hexadecyltrimethylammonium cations and their subsequent decomposition contribute to the ultrafast expansion and exfoliation of bulk black phosphorus crystals. In addition, the as-exfoliated flakes show improved stability due to the protection of hexadecyltrimethylammonium chloride. This exfoliation method, together with the findings, should shed light on the development of new exfoliation methods for preparing few-layer black phosphorus flakes in various liquid systems, thus facilitating the future applications of black phosphorus.
研究领域:
材料科学
·
化学
✓ 已验证
产品关联
DOI
SEPARATION AND PURIFICATION TECHNOLOGY
·
2022
·
IF 9.136
Haoran Sun,Wanzhong Yin
To achieve efficient separation of magnesite from quartz, it is crucial to develop highly selective collector. In this work, for the size range of samples was −74 + 35 μm (d80 = 70.96 μm), the effect of palmitoyl trimethylammonium chloride (PTAC) on the flotation separation of magnesite and quartz was studied for the first time. Micro-flotation test results indicated that PTAC had a selective-collection influence on quartz and that magnesite separation from quartz could be accomplished at pH 7.0 and 30 mg/L PTAC. Zeta-potential and contact-angle tests indicated that PTAC could selectively increased the isoelectric point and hydrophobicity of quartz surface, but had no such effect on magnesite. Fourier-transform infrared (FTIR) spectroscopy and field emission scanning electron microscopy (FESEM) coupled with energy dispersion spectroscopy (EDS) measurements revealed that PTAC was mainly adsorbed on the surface of quartz, and selective adsorption of PTAC onto quartz surface could be attributed to electrostatic attraction and hydrogen bonds . Molecular dynamics simulation (MDS) further revealed the high selectivity of PTAC adsorption on quartz, through the peak position of PTAC molecular number density, water diffusion coefficient and the interaction energy between PTAC and the minerals. Finally, extended Derjaguin-Landau-Verwey-Overbeek theoretical calculation showed that the addition of 30 mg/L PTAC could change the total force V T ED between magnesite and quartz from attraction to repulsion, which was conducive to the separation between them.
研究领域:
矿物加工工程
·
表面化学
✓ 已验证
DOI
高影响因子
Materials Research Express
·
2022
·Vol. 9
·期 2
·025309
·
IF 2.025
Jingdan Zhang,Yongqing Zhai
To improve the application performance of organic montmorillonite (OMt) and meet the OMt performance requirements of different fields, herein, we developed a synergistic modification method to prepare cationic–nonionic OMt (CN-Mt) using the emulsifier OP-10 and hexadecyltrimethylammonium chloride (CTAC) as comodifiers. The structure, morphology and properties of CN-Mt, cationic-OMt (C-Mt) and nonionic OMt (N-Mt) were studied by XRD, SEM, DSC, and contact angle and swell index measurements. CN-Mt has a larger layer spacing and thinner lamellae, which are obviously different from those of C-Mt and N-Mt. Moreover, CN-Mt was hydrophobic due to its denser organic surface molecules. The interlayer spacing of CN-Mt is positively related to the amount of modifier, and the amount of OP-10 contributes more to the interlayer spacing than CTAC. When the amounts of OP-10 and CTAC are 1.3 and 0.8 times the Mt cation exchange capacity (CEC), the interlayer spacing of the optimal CN-Mt is 4.49 nm, which is significantly higher than that of C-Mt (4.11 nm) at a 2.9 CEC, N-Mt (4.26 nm) at a 1.7 CEC and CN-Mt (4.20 nm) at a 0.9OP-10 + 1.5CTAC CEC. Benefitting from its structural merits, CN-Mt shows a higher degree of lamella separation, peeling and dispersion than C-Mt and N-Mt, as well as good thermal stability. Moreover, the lipophilicity and expansion of CN-Mt in medium- and low-polarity media are better than those of single-component OMt. Therefore, the structure and properties of CN-Mt can be controlled by adjusting the types and amount of modifier, further meeting the performance requirements of various application fields.
研究领域:
材料科学
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化学工程
✓ 已验证
DOI
高影响因子
SCIENCE OF THE TOTAL ENVIRONMENT
·
2018
·
IF 4.61
Min-Yong Lee,Wen-Long Wang,Zi-Bin Xu,Bei Ye,Qian-Yuan Wu,Hong-Ying Hu
Dodecyltrimethylammonium chloride (DTAC) is a quaternary ammonium compound (QAC) that is a widespread contaminant in environmental media and therefore of increasing concern. The synergistic effect with UV irradiation and persulfate (UV/PS) was used to degrade DTAC . The removal of DTAC was 91% with the PS dosage of 75.6 μM (UV/PS) and UV fluence of 870 mJ·cm −2 . The second-order rate constants of DTAC with HO and SO 4 − were determined to be k HO , DTAC (4.2 ± 0.18) × 10 9 M −1 s −1 and k SO 4 ∙− , DTAC (2.5 ± 0.27) × 10 9 M −1 s −1 , respectively. The contributions of HO and SO 4 − to DTAC degradation in the UV/PS were found to be 30% and 62% at pH 7, respectively. The contributions of SO 4 − and HO were not significantly influenced by acidic medium (pH 3–pH 7), whereas they were significantly affected by basic medium (pH 7–pH 11). The wastewater matrixes of HCO 3 − , Cl − and humic acid inhibited the DTAC elimination, whereas NO 3 − and SO 4 2− had no significant impact on its elimination. Moreover, the k obs,DTAC in the reverse osmosis influent (ROI) and reverse osmosis concentrate (ROC) were examined to be 0.04 to 0.1 min −1 and 0.02 to 0.05 min −1 , respectively, as the PS dosage increased from 18.9 to 113.4 μM. The inhibitive effects of matrix in ROI and ROC was 70% and 81%, respectively. The contribution of radical scavenging effect by matrix ROI and ROC was more significant to DTAC degradation than UV scattering effect in ROI and ROC matrices. A UV fluence of 1305 mJ·cm −2 was necessitated for complete detoxification and DTAC solution by UV/PS.
研究领域:
环境科学
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化学工程
✓ 已验证
产品关联
DOI
PubMed
高影响因子
LANGMUIR
·
2010
·
IF 3.898
Yao Zhou,Wenshuang Lin,Huixuan Wang,Qingbiao Li,Jiale Huang,Mingming Du,Liqin Lin,Yixian Gao,Ling Lin,Ning He
Biosynthesized gold nanoparticles (GNPs) were transferred from water to a hydrophobic ionic liquid (IL), [Bmim]PF6, with the assistance of alkyl trimethyl ammonium bromide. The phase transfer mechanism was illustrated through the exemplification of cetyltrimethyl ammonium bromide (CTAB). Interaction between GNPs and CTAB was demonstrated through zeta potential analysis. Moreover, an anion-exchange process was discovered between CTAB and IL. During the process, the hydrophobic CTAPF6 formed in situ on the GNPs led to the hydrophobization and thus phase transfer of the GNPs. The phase transfer efficiency was found to be size-dependent.
研究领域:
纳米生物学
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材料科学
✓ 已验证
DOI
高影响因子
ORGANIC & BIOMOLECULAR CHEMISTRY
·
2013
·Vol. 12
·期 9
·1448-1453
·
IF 3.568
Xue-Qi Zhang,Zhong-Xia Wang
Nickel-catalyzed cross-coupling of aryltrimethylammonium triflates and amines was carried out under mild conditions. The reaction has a broad scope of substrates and can be performed by a one-pot procedure from an aryldimethylamine.
研究领域:
有机化学
·
催化化学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
ACS Nano
·
2025
·
IF 16
Heng Liu,Long Yang,Ting Shen,Changyuan Li,Te Kang,Huanhuan Niu,Wei-Hsiang Huang,Chun-Chi Chang,Menghao Yang,Guozhong Cao,Chaofeng Liu
Layered hydrate vanadates are promising cathode materials for aqueous zinc-ion batteries (AZIBs). Various intercalants have been preinserted into the interplanar space of hydrate vanadates with significantly enhanced kinetics and stabilized structures. However, such an enhancement is induced by various intercalants, and the relationship between the property enhancement and the type of intercalant still needs to be revealed. In this work, the distortion of octahedra induced by the preintercalation of benzyltrimethylammonium (BTA+) cations into hydrate vanadium pentoxide (V2O5·nH2O, VOH) and the change in ligand field are studied using synchrotron X-ray pair distribution function (PDF) and X-ray absorption fine structure (XAFS). Variations in the local coordination of vanadium alter the ligand field, decreasing the energy of the lowest unoccupied orbitals (e*), which leads to an increased electrochemical potential. Additionally, the introduced BTA+ facilitates fast ion diffusion and stabilizes the layer structure. A cathode with a distorted local structure delivers a specific capacity of 408 mAh/g at 0.5 A/g, with a capacity retention of 95% after 3000 cycles at 8 A/g.
研究领域:
材料科学
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电化学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
IRANIAN POLYMER JOURNAL
·
2015
·Vol. 24
·期 9
·747-758
·
IF 1.806
Gao Xin,Chen Keli,Zhang Heng,Yan Xuejing
A rapid microwave-assisted cationic synthesis of cellulosic polymer by grafting glycidyl trimethyl ammonium chloride (GTMAC) onto parenchyma cellulose (PC) from bagasse pith under low-power condition is reported. The effects of the microwave power, exposure time, GTMAC charge, water content, and aqueous-organic solvents by volume ratio were evaluated by determining cationization parameters such as yield, degree of substitution (DS), zeta potential, and charge density. The experimental results showed that the water-soluble and -insoluble fractions of cationic parenchyma cellulose (CPC) were obtained and their optimal DS were determined to be 0.72 and 0.63 at the microwave power of 100 W for 20 min, respectively. Surface cationization of PC resulted in an increase in zeta potential and charge density over the unmodified cellulose. In comparison with the original PC, the intrinsic viscosity of the cationic products decreased significantly. The presence of GTMAC on the surface of PC was confirmed by Fourier transform infrared spectroscopy. The crystallinity and surface structure of original cellulose and CPCs were also analyzed through X-ray diffraction and scanning electron microscopy, respectively. This work provided an efficient and economical feasibility to produce a cationic biopolymer from cellulose.
研究领域:
化学工程
·
材料科学
✓ 已验证
产品关联
DOI
高影响因子
ACS Applied Materials & Interfaces
·
2014
·
IF 5.9
Xiuhua Li,Guanghui Nie,Jinxiong Tao,Wenjun Wu,Liuchan Wang,Shijun Liao
3,3′-di(4″-methyl-phenyl)-4,4′-difluorodiphenyl sulfone (DMPDFPS), a new monomer with two pendent benzyl groups, was easily prepared by Suzuki coupling reaction in high yield. A series of side-chain type ionomers (PAES-Qs) containing pendant side-chain benzyltrimethylammonium groups, which linked to the backbone by alkaline resisting conjugated C–C bonds, were synthesized via polycondensation, bromination, followed by quaternization and alkalization. To assess the influence of side-chain and main-chain aromatic benzyltrimethylammonium on anion exchange membranes (AEMs), the main-chain type ionomers (MPAES-Qs) with the same backbone were synthesized following the similar procedure. GPC and 1H NMR results indicate that the bromination shows no reaction selectivity of polymer configurations and ionizations of the side-chain type polymers display higher conversions than that of the main-chain type ones do. These two kinds of AEMs were evaluated in terms of ion exchange capacity (IEC), water uptake, swelling ratio, λ, volumetric ion exchange capacity (IECVwet), hydroxide conductivity, mechanical and thermal properties, and chemical stability, respectively. The side-chain type structure endows AEMs with lower water uptake, swelling ratio and λ, higher IECVwet, much higher hydroxide conductivity, more robust dimensional stability, mechanical and thermal properties, and higher stability in hot alkaline solution. The side-chain type cationic groups containing molecular configurations have the distinction of being practical AEMs and membrane electrode assemblies of AEMFCs.
研究领域:
材料科学
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化学工程
✓ 已验证
产品关联
DOI
PubMed
高影响因子
Soft Matter
·
2022
·Vol. 18
·期 10
·2072-2081
·
IF 4.046
Feixue Gong,Na Du,Wanguo Hou
We recently found that rough glass surfaces (RGSs) can in situ mediate the micelle-to-vesicle transition in single-component solutions of simple single-tailed amphiphiles (STAs), but only result in a relatively small number of vesicles coexisting with a large number of micelles. In the current work, a dehydration–rehydration (DHRH) method was used to induce the formation of vesicles in the single-component aqueous solutions of alkyltrimethylammonium bromides (CnTABs, n = 12, 14, and 16), a kind of typical cationic STAs. That is, a CnTAB micelle solution dropped on smooth glass surfaces (SGSs) was first dried, and the dried CnTAB aggregates were then rehydrated in a monomer solution of CnTAB. A large population of vesicles and even pure vesicle (or vesicle-dominated) systems were obtained, indicating that the DHRH process could more effectively induce the formation of STA vesicles than RGS in situ mediation. The so-obtained vesicles were characterized using DLS, FF-/cryo-TEM, AFM, SAXS, and fluorescence techniques, and their stability was determined. In addition, the effects of the conditions of DHRH and the chain length of CnTABs on the vesicle formation were examined. It was demonstrated that the vesicles can be formed as long as the concentrations of CnTABs in the rehydrated systems are higher than their critical micelle concentrations. The size and wall thickness of vesicles increase with an increase in chain length. A possible mechanism for the DHRH-induced vesicle formation is proposed: bilayer sheets are formed on SGSs during dehydration, and then detached from the SGSs to form vesicles during rehydration. A highly interdigitated structure of alkyl chains between two leaflets was identified in the bilayers, which probably is the origin of the formation and stability of STA vesicles.
研究领域:
生物物理学
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胶体与界面化学
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材料科学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
FUEL
·
2024
·
IF 6.7
Ying Chen,Zhengyu Tang,Yu-Cai He,Cuiluan Ma
Maize straw underwent pretreatment with stearyl trimethyl ammonium bromide (STAB) combined with ortho -hydroxybenzoic acid (OHA), and the parameters of the pretreatment process were optimized through single-factor and orthogonal experiments. The results demonstrated that 77.2 % lignin and 92.4 % xylan were removed through the combined pretreatment at the severity factor (LogR 0 ) = 4.13, resulting in an increase in the enzymatic hydrolysis activity to 90.8 %. After pretreatment, the crystallinity of the material elevated significantly to 63.6 %, the surface structure became rough, and the accessibility elevated to 667.4 mg/g. These positive changes jointly improved the efficiency of enzymatic hydrolysis. By-products including 3.7 g/L xylo -oligosaccharides, 1.1 g/L 5-hydroxymethylfurfural, 0.6 g/L furfural, 1.2 g/L formic acid, and 1.5 g/L acetic acid co-produced during STAB+OHA combination pretreatment. Meanwhile, the reusability experiment of up to 5 cycles confirmed the sustainable utilization of this combined pretreatment system. This pretreatment technology theoretically facilitated the diversification of fuel and chemical production.
研究领域:
生物化学
·
可再生能源
✓ 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）