COLLOIDS AND SURFACES A-PHYSICOCHEMICAL AND ENGINEERING ASPECTS
·
2022
·
IF 5.518
Yawei Shi,Guobin Song,Anqi Li,Jun Wang,Haonan Wang,Ya Sun,Guanghui Ding
A series of composite aerogels with different precursor mass ratios were prepared from graphene oxide (GO) and chitosan (CS) by conducting the crosslinking step after lyophilization, the method of which was recently found beneficial to enhance the adsorptive properties of aerogels . The composite aerogels were then employed for the adsorption of methyl orange (MO) and methylene blue (MB) from water, and the one prepared at GO:CS= 1:2 (w/w) was selected as the optimal compromising the adsorption and mechanical properties. The maximum adsorption amounts of MO and MB were calculated to be 543.4 and 110.9 mg/g at 25 °C. Especially, the effects of pH on adsorption of MO and MB in both single and binary systems were investigated in detail. The aerogel possessed pH-responsive feature for single dye adsorption, tending to adsorb MO at low pH while to adsorb MB at high pH. In the binary system, the pH-responsive feature remained and selective adsorption was observed at low initial dye concentration. In contrast, synergistic adsorption occurred instead at high initial concentration, and MB and MO could be efficiently removed simultaneously in the whole pH range of 3–11.
研究领域:
环境科学
·
材料科学
·
化学工程
·
水处理
·
吸附技术
✓ 已验证
DOI
高影响因子
CERAMICS INTERNATIONAL
·
2017
·Vol. 44
·期 6
·5842-5847
·
IF 2.986
Lirong Yang,Chunmei Wang,Zhigang Liu,Xiaoyu Liu,Yang Song,Xiaoxin Feng,Baoqiang Zhang
Anatase TiO 2 coatings prepared by solvothermal process in a neutral ethanol solution of isopropyl titanate at 160 °C have been grown on slag wool fibers (SWF) which were modified by hexadecyltrimethylammonium bromide (CTAB) in advance. X-ray diffraction patterns confirmed the coatings are of a nanocrystalline anatase structure, and scanning electron microscopy observations and energy-dispersive X-ray spectrum revealed a continuous coverage of TiO 2 formed on the fiber surfaces. The photocatalytic activity of the samples was tested by the photocatalytic degradation of methylene blue (MB) solution. The results show that CTAB modified slag wool fibers (CMSWF) are not a suitable adsorbent for MB due to their weaker negative surface charges. Anatase TiO 2 coated CMSWF display higher photocatalyst activity than anatase TiO 2 coated SWF without CTAB modification, and Anatase TiO 2 coated CMSWF are relatively stable under UV-light irradiation.
研究领域:
材料科学
·
环境功能材料
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表面改性
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光催化
·
纳米涂层
✓ 已验证
DOI
高影响因子
JOURNAL OF MEMBRANE SCIENCE
·
2019
·
IF 7.015
Ziqiang Tong,Xiufeng Liu,Baoquan Zhang
A series of sphere-like polyelectrolyte complexes (PECs) and their homogeneous polyelectrolyte complex membranes (HPECMs) were synthesized by using sodium carboxymethyl cellulose (CMCNa) and poly(diallyldimethylammonium chloride) (PDDA). Different compositions or ionic complexation degrees (ICD) of PECs could be characterized by FT-IR spectra. The circular dichroism spectrum (CD) and field emission scanning electron microscopy (FESEM) were employed to examine the conformation and morphology of PECs, respectively. Zeta (ζ) potential was utilized to investigate the charge density of PEC particles while the surface hydrophilicity of HPECMs was studied by using contact angle (CA) meter. When subjected to ethanol dehydration, HPECMs revealed a satisfactory pervaporation performance and desired anti-trade-off phenomenon. For HPECM 0.31 and HPECM 0.57, the permeation fluxes were 2.25 kg m −2 h −1 and 2.93 kg m −2 h −1 , and the water content in permeate reached up to 99.35 wt% and 99.38 wt%, with respect to 10 wt% water in feed under 70 °C. All the results indicated that small-sized and sphere-like PECs were truly in favor of enhancing the pervaporation performance in ethanol dehydration.
研究领域:
高分子科学
·
膜分离技术
·
化学工程
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材料科学
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物理化学
✓ 已验证
DOI
高影响因子
Green Energy & Environment
·
2019
·Vol. 4
·期 4
·424-431
·
IF 0
Yangyang Zhang,Xinli Tong,Linhao Yu,Lingwu Meng,Pengfei Guo,Song Xue
The catalytic transformation of furfuryl alcohol and hexose into value-added chemicals have been investigated with a series of polymer-based catalysts including poly(styrenesulfonic acid) (PSS), graphite oxide-doped poly(styrenesulfonic acid) (PSS-GO), and graphite-doped poly(styrenesulfonic acid) (PSS-C). It is found that the selective conversion of furfuryl alcohol to methyl levulinate (MLE) was successfully performed with PSS as the catalyst, in which a 96.4% yield is attained in methanol solvent. Moreover, the efficient dehydration of d -fructose to produce 5-hydroxymethylfurfural (HMF) has also been achieved using PSS-GO as the catalyst, where a 76.5% yield of HMF was obtained in N -methylpyrrodinone solvent. The effects of reaction temperature, time and solvent were investigated. Furthermore, the used catalysts have been respectively characterized by XRD, TG, FTIR, SEM and TEM techniques to reveal the physical properties and structures of these polymeric catalytic materials.
研究领域:
催化化学
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生物质能源
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绿色化学
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有机转化
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高分子材料
·
可持续化学
·
生物基化学品
✓ 已验证
DOI
JOURNAL OF APPLIED POLYMER SCIENCE
·
2012
·Vol. 125
·期 4
·2867-2873
·
IF 1.289
Yehai Yan,Na Lu,Jian Cui,Jinfang Zhang
A new fluorescent copolymer, poly(1-vinylimidazole- co -(1-pyrene) methyl 2-methyl-2-propenote) (VI- co -PyMMP), has been designed and synthesized by a free-radical copolymerization of VI and PyMMP as well as characterized using ultraviolet (UV), Fourier transform infrared spectroscopy (FTIR), 1 H NMR, and fluorescence spectroscopies. The monomer reactivity ratios are determined by two methods of Fineman-Ross ( r 1 = 0.28 ± 0.04 for VI, r 2 = 1.32 ± 0.11 for PyMMP) and Kelen-Tüdös ( r 1 = 0.23 ± 0.05, r 2 = 1.22 ± 0.12). Based on the reactivity ratios, the monomer sequence lengths and Q and e for PyMMP monomer are further calculated. The results suggest that the copolymerization of VI and PyMMP is a nonideal copolymerization without an azeotropic point (i.e., r 1 < 1, r 2 > 1 and r 1 r 2 < 1) and has a low alternation tendency. The conclusions drawn in this work may not only direct the later synthesis of the copolymers but also enrich the database of free-radical copolymerization. © 2012 Wiley Periodicals, Inc. J Appl Polym Sci, 2012
研究领域:
高分子化学
·
功能高分子
·
荧光材料
·
聚合物合成
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材料化学
✓ 已验证
DOI
高影响因子
RSC Advances
·
2017
·Vol. 7
·期 12
·6972-6980
·
IF 3.108
Xiaohui Liu,Qian Zhu,Qiuyan Zhang,Yanguang Zhang,Chen Ding
Over the past few years, ionic liquids (ILs) have been widely reported as reaction media for reverse atom transfer radical polymerization (ATRP). In particular, almost all the ILs with the structure [Hmim][RCOO] (R represents an alkyl group) have been used as ligands for a reverse ATRP system. However, the facile, simple and low-cost ILs, 1-alkyl-3-methylimidazole chloride ([Rmim][Cl]), have rarely been employed as ligands for reverse ATRP. In this article, a [Rmim][Cl] was successfully employed as a ligand for the reverse ATRP of methyl methacrylate with Fe(III) as catalyst and 2,2′-azobisisobutyronitrile as initiator. The key to success is to adjust the FeCl3/[Rmim][Cl] molar ratio value to 1 : 1. The results indicated that the polymerization with [Rmim][Cl] as a ligand proceeded in a controlled/“living” fashion, as evidenced by the first-order kinetic plot, low polydispersity index values, and increase in polymer molecular weight with monomer conversion. The effects of various experimental parameters, including different catalysts, reaction temperatures, solvents, and molar ratios of FeCl3/[Rmim][Cl], on the polymerization were investigated in detail. Furthermore, 1H NMR and gel permeation chromatography analyses confirmed the halogen-containing chain-end functionality of the resultant polymer.
研究领域:
高分子化学
·
有机合成
·
催化化学
·
功能材料
·
可控自由基聚合
✓ 已验证
DOI
高影响因子
JOURNAL OF SOILS AND SEDIMENTS
·
2016
·Vol. 17
·期 2
·536-542
·
IF 2.206
Zhang Jinyang,Li Chuxian,Wang Dingyong,Zhang Cheng,Liang Li,Zhou Xiong
Purpose The environmental safety of both nano-TiO 2 particles and mercury (Hg) pollution has been of widespread concern. Soils and sediments were the main receiving environments of nano-TiO 2 and Hg. There was a strong association between nano-TiO 2 with Hg compounds. Very limited research has been carried out on the impact of nano-TiO 2 on the environmental behavior of Hg in sediments. The objective of this study was to investigate the effects of nano-TiO 2 on the release and transformation of Hg in sediments. Materials and methods Two types of TiO 2 nanoparticles were employed. Sediment samples were collected in the water level fluctuating zone of the Three Gorges Reservoir, China. Sediment samples spiked with HgCl 2 solution were taken as Hg-contaminated sediments. The flooding experiments were conducted using capped borosilicate glass bottles containing 300 ml TiO 2 suspensions (0.2 g L −1 and 0.4 g L −1 ) and 30 g original or Hg-contaminated sediment samples outdoors. All experiments were conducted in triplicate. Water samples were collected at determined interval times over a 60-day period. Sediments were collected on the 60th day. Total Hg (THg) and methylmercury (MHg) in both water and sediment samples and Hg speciation just in sediment samples were determined. A series of control samples without TiO 2 addition were also prepared. Results and discussion The results showed that nano-TiO 2 particles at high content (4 g kg −1 ) promoted the release of Hg in sediments, and the anatase particles showed a stronger effect. Methyl Hg concentrations in waters of nano-TiO 2 treatments significantly decreased by the 10th day. The effect of nano-TiO 2 greatly depended on anatase and rutile particles. After that, methyl Hg concentrations had no significant difference between nano-TiO 2 treatments and the control, except 2 g kg −1 rutile treatment by the 20th day. The changes of Hg speciation in sediments demonstrated that nano-TiO 2 inhibited the transformation of Hg-bound organic matter into the oxidated state, especially upon 2 g kg −1 rutile treatment. This was consistent with the lower MHg concentrations in the 2 g kg −1 rutile treatment. Conclusions Both anatase and rutile nano-TiO 2 were found to affect the release of Hg in sediment. Nano-TiO 2 promoted THg release in sediments and posed an increased risk of Hg contamination in waters, especially for anatase particles. Moreover, nano-TiO 2 inhibited the methylation process of Hg in sediments at the initial stage of flooding and could affect the transformation of Hg speciation in sediments, especially for low-content rutile particles.
研究领域:
环境科学
·
地球化学
·
水体生态学
·
污染控制
·
环境毒理学
✓ 已验证
DOI
高影响因子
APPLIED SURFACE SCIENCE
·
2010
·Vol. 257
·期 9
·3920-3923
·
IF 1.616
Hongxu Guo,Jianhua Chen,Wen Weng,Shunxing Li
A visible light-driven photocatalyst, C-doped Zn 3 (OH) 2 V 2 O 7 , prepared by a hydrothermal method was studied. The as-prepared catalyst was characterized by SEM, XRD , DRS, and XPS , and exhibited efficient photocatalytic activity in the degradation of methylene blue (MB) under visible-light irradiation. Besides decoloring, the decomposition of MB was also observed, further demonstrating the performance of the photocatalyst. The carbon existing on the surface of Zn 3 (OH) 2 V 2 O 7 nanorods was free and in carbide form. Dye degradation followed first-order kinetics, and was explained on the basis of the Langmuir–Hinshelwood mechanism.
研究领域:
材料化学
·
光催化
·
纳米材料
·
环境化学
·
无机合成
✓ 已验证
DOI
高影响因子
POSTHARVEST BIOLOGY AND TECHNOLOGY
·
2018
·
IF 3.112
Yurong Ma,Qingfeng Ban,Jingying Shi,Tiantian Dong,Cai-Zhong Jiang,Qingguo Wang
The effects of 1-methylcyclopropene (1-MCP) treatment, storage time, and shelf life and temperature on phenolic concentrations and antioxidant activity in apple peel and flesh of ‘Jonagold’ apple ( Malus domestica Borkh) have been investigated. Hyperoside and chlorogenic acid were the most abundant phenolic compounds in the peel and flesh, respectively. The flesh had lower concentrations of individual phenolics, total phenolics, flavonoids and lower antioxidant activity (determined by 1,1-diphenyl-2-picrylhydrazyl (DPPH) radical scavenging assay) than the peel. In addition, the profiles of phenolics as well as the changing patterns of individual phenolics also differed between the peel and the flesh. After long-time storage (180 d), the greatest decrease of concentrations was the concentrations of hyperoside (27 %) in the peel and total phenolics (35 %) in the flesh. Also, during the 90–180 d storage period, hyperoside and rutin in the peel, chlorogenic acid in the flesh, and flavonoids and antioxidant activity decreased in both peel and flesh tissues. Individual phenolics exhibited different stabilities during the early stages after harvest. 1-MCP reduced the reduction in the concentrations of hyperoside in the peel, chlorogenic acid in the flesh, and total phenolics, flavonoids and antioxidant activity in both the peel and flesh tissues during storage and shelf life. However, for quercetin and rutin, the protective effect of 1-MCP was only observed during the shelf life period. Overall, phenolic compounds responded variously to storage, shelf life, shelf temperature and 1-MCP treatment.
研究领域:
食品科学
·
植物生理学
✓ 已验证
产品关联
DOI
高影响因子
PHYSICA STATUS SOLIDI A-APPLICATIONS AND MATERIALS SCIENCE
·
2017
·Vol. 214
·期 11
·1700538
·
IF 1.775
Peihua Wangyang,Hui Sun,Xinghua Zhu,Dingyu Yang,Xiuying Gao,Wenyi Liu,Yan Chen,Haibo Tian,Sibo Huanglong
A promising photodetector based on CH 3 NH 3 PbI 3 single crystal under visible light and X-ray irradiation is reported. The CH 3 NH 3 PbI 3 crystal grown by inverse temperature crystallization acts as the absorber material directly converting visible light and the impinging X-ray photons to electron hole pairs, respectively. The underlying photoelectric response mechanism behind the observation under visible light and X-ray irradiation is carefully discussed. Remarkably, the perovskite detectors demonstrate a good air-exposure stability for more than 2 months with encapsulation. The results demonstrate that the CH 3 NH 3 PbI 3 single crystal has a great potential for application in the visible light and X-ray detection.
研究领域:
材料科学
·
凝聚态物理
·
核医学
·
生物医学工程
·
辐射检测
·
半导体器件
✓ 已验证
DOI
高影响因子
COMBUSTION AND FLAME
·
2023
·
IF 4.4
Xiaodong Wang,Lili Ye,Xiaoyuan Zhang,Zhihe Zhang,Jiuzhong Yang,Long Zhao
Acetaldehyde, ethylene oxide , and vinyl alcohol are three C 2 H 4 O isomers that are ubiquitous in combustion over a wide temperature range. A comprehensive reaction kinetics study has been performed for reactions that occur on the same C 2 H 4 O potential energy surface , mainly including the unimolecular reactions of three C 2 H 4 O isomers and the recombination reaction of CH 3 with HCO. Temperature- and pressure-dependent rate coefficients were updated or newly predicted by performing quantum chemical calculations coupled with RRKM/master equation simulations. The dominance of C C bond fission is reconfirmed for acetaldehyde decomposition at higher temperatures. The negligible contribution of CH 4 + CO channel from usual tight intramolecular H-shift transition state provides indirect evidence for previously reported roaming mechanism that was proposed to explain the observation of CH 4 + CO in acetaldehyde pyrolysis . For ethylene oxide pyrolysis , current experiment and kinetic prediction have a good consistency in branching ratios between the formation of acetaldehyde and vinyl alcohol products. The radicals of CH 3 + HCO can also be directly generated from ethylene oxide through a well-skipping reaction mechanism especially at higher temperatures. For CH 3 + HCO recombination, we highlight the importance of CH 3 CO + H channel that was often overlooked previously. Kinetic simulations show that the incorporation of updated rate coefficients and newly identified channels results in a measurable influence on C2 chemistry , indicating the possibility and necessity of further improvement of core mechanism in combustion kinetic models .
研究领域:
物理化学
·
燃烧化学
·
反应动力学
·
量子化学计算
·
分子反应机制
✓ 已验证
DOI
高影响因子
DESIGNED MONOMERS AND POLYMERS
·
2019
·
IF 1.528
Meng-Di Chen,Guo Zhang,Shi-Chang Chen,Xian-Ming Zhang,Wen-Xing Chen
In this study, 9-anthracenemethyl methacrylate (AMMA) and styrene (St) as monomers and benzoyl peroxide as an initiator were used to synthesize P(St-co-AMMA), a macromolecule tracer with a fluorescence effect, via free radical copolymerization. A fluorescent online detection device was built on the basis of the principle of fluorescence online detection by using the single-screw extrusion platform of a torque rheometer to explore the effect of the amount of macromolecular tracer and screw speed on the residence time distribution of polystyrene in single-screw extrusion. Fourier transform infrared spectroscopy, 1H-NMR, thermal stability, fluorescence properties, and rheological properties show that the resulting product P(St-co-AMMA) has a degree of thermal stability, fluorescence, and rheological properties similar to polystyrene, so this product can be used to characterize the residence time distribution during single-screw extrusion. The amount of macromolecular tracer P(St-co-AMMA) does not affect the residence time distribution of polystyrene during single-screw extrusion processing, meanwhile, the minimum residence time decreases and the residence time distribution becomes narrow as the screw speed increases, that is, the axial mixing capacity of the single-screw extruder decreases as the screw speed increases.
研究领域:
高分子化学
·
材料科学
·
聚合物加工工程
✓ 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）