JOURNAL OF HAZARDOUS MATERIALS
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2015
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IF 4.529
Shaopeng Rong,Yabing Sun
This work describes the application of plasma generated by water falling film dielectric barrier discharge for the degradation of triallyl isocyanurate (TAIC). The results indicated that TAIC solution of 1000 mg/L was effectively removed within 60 min treatment at 120 W output power. Six intermediates were identified and a possible evolution of the TAIC degradation process was continuously proposed basing on the results of mass spectrum analysis. The effects of metal ions and radical scavengers were investigated. Results showed that whatever hydrogen radical scavengers (carbon tetrachloride, perfluorooctane) or hydroxyl radical scavengers ( iso -propyl alcohol, tert -butyl alcohol) all could further enhance the degradation processes, and both kings of radical scavengers could promote the generation of H 2 O 2 . In the present study, we employed a novel method by introducing the mixed additives of Fe 2+ and radical scavengers into the plasma. It was found that the reaction rate constant and energy efficiency were improved by 309.2% and 387.8%, respectively. Among the mixed additives, Fe 2+ could promote the decomposition and increase the oxidizing power of H 2 O 2 , which is generated from the plasma discharge and greatly enhanced by the radical scavengers.
研究领域:
环境科学
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化学工程
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等离子体技术
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产品关联
DOI
PubMed
高影响因子
TALANTA
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2018
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IF 4.244
Quan Wang,Shigang Shen
A novel porous monolithic column was synthesized via in situ free-radical polymerization within a stainless steel column (50 × 4.6 mm i.d.) by using triallyl isocyanurate and methyl methacrylate as co-monomers, ethylene glycol dimethacrylate as a crosslinking agent, 1,4-butanediol, 1- dodecanol , and N, N-dimethylformamide as tri-porogens, and azobisisobutyronitrile as an initiator. The optimized monolithic columns were investigated by scanning electron microscopy, a nitrogen absorption-desorption apparatus, and mercury intrusion porosimetry. The effect of mobile phase composition and temperature on chromatographic behavior was studied in detail as well. The results showed that homemade monolithic columns not only have relative uniform porosity structure, low back pressure, and high thermal stability, but also show high column efficiency, the theoretical plates number of the new polymer monolithic column exceeded 31,000 plates m −1 . Good resolution was achieved for HPLC separation of small molecules, including polycyclic aromatic hydrocarbons , isomers of phenols, and the Chinese herbal medicine notoginseng. Methodological validation of six drugs in notoginseng show that correlation coefficients of the linear regressions were in the range of 0.9989–0.9997; the value of relative standard deviation for precision were in the range of 1.37–4.21% for intra-day and 0.34–5.31% for inter-day, respectively; the values of accuracy expressed by recovery were in the range of 100.57–102.51%, 95.18–102.68%, 101.61–102.82%, 100.94–102.40%, 100.99–103.15% and 99.49–103.91% for the six drugs in order, respectively. Taking aromatic hydrocarbons as samples, the relative standard deviation values of the run-to-run (n = 5) and column-to-column (n = 5) based on peak area were < 2.01% and 2.39%, and two RSDs based on retention time were < 2.56% and 2.23%, respectively. The result showed that the polymer monolithic column has good separation ability and high permeability for small molecular substances.
研究领域:
分析化学
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药学
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材料科学
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DOI
PubMed
高影响因子
CHROMATOGRAPHIA
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2018
·Vol. 82
·期 8
·1285-1293
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IF 1.401
Wang Huimin,Guo Bin,Pang Xiaoya,Yu Huan,Liu Haiyan,Yan Hongyuan,Han Dandan,Guo Huaizhong,Bai Ligai
A poly(NMA-ST- co -TAIC-EDMA) monolithic column was prepared by redox initiation method using N -methylolacrylamide (NMA) and styrene (ST) as co-monomers. The composite monolith was characterized by scanning electron microscopy (SEM) and nitrogen adsorption–desorption isotherm and was used as a solid phase extraction (SPE) absorbent for enrichment of β -sitosterol by high performance liquid chromatography (HPLC). Under the optimum conditions for extraction and determination, the calibration equation was y = 1.02247 x + 0.1766; the linear range was 0.015–0.75 mg mL −1 and the linear regression coefficient was 0.998. The limit of detection (LOD) and the limit of quantification (LOQ) were 0.006 mg mL −1 and 0.02 mg mL −1 , respectively. The spiked recoveries of β -sitosterol in edible oil samples were 83.60–103.88%; precisions for intra-day and inter-day assays presented as relative standard deviations were less than 6.0% and 6.2%, respectively. The enrichment factor of β -sitosterol was 60 and the results showed that the monolithic column had high selectivity and good permeability as an on-line SPE absorbent for the enrichment and determination of β -sitosterol from edible oils.
研究领域:
分析化学
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食品科学
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材料科学
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产品关联
DOI
高影响因子
RSC Advances
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2014
·Vol. 4
·期 44
·23036-23042
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IF 3.708
Songqi Ma,Yanhua Jiang,Xiaoqing Liu,Libo Fan,Jin Zhu
The utilization of soybean oil-based UV coatings depends on the introduction of petroleum-based comonomers or crosslink agents. Thus, in this paper, a bio-based crosslink agent (GACA) for UV curable coatings was synthesized from gallic acid and its chemical structure was confirmed by FT IR, 1H NMR and 13C NMR. Crosslinked networks with high biobased content of more than 88% were obtained after co-photopolymerization between acrylated epoxidized soybean oil (AESO) and GACA. The thermal, mechanical and coating properties of these GACA crosslinked AESO networks were investigated and a commonly used crosslink agent triallyl isocyanurate (TAIC) was used as the control. GACA exhibited more functional groups and better copolymerization with AESO than TAIC, resulting in the higher gel content, crosslink density, tensile strength and modulus as well as much better coating properties (reflected by the higher pencil hardness, better wear resistance and adhesion) of GACA crosslinked AESO networks than TAIC crosslinked AESO networks. These results indicated that GACA exhibited great potential to replace petroleum-based crosslink agents such as TAIC, and high-performance soybean oil-based UV-cured coatings with high biobased content could be achieved after introducing GACA.
研究领域:
材料科学
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化学工程
✓ 已验证
产品关联
DOI
高影响因子
POLYMER DEGRADATION AND STABILITY
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2021
·
IF 5.03
Qingkun Liu,Jia Li,Yunchao Jiang,Chuanbo Cong,Lixin Xu,Ying Zhang,Xiaoyu Meng,Qiong Zhou
The degradation of peroxide-cured EPDM and sulfur-cured EPDM in an acid solution (12.5 ppm H 2 SO 4 +1.8 ppm HF) was investigated, and it was found that the degradation of the two in an acid solution was different. The degradation degree of the sulfur curing system is lower than that of the peroxide curing system. During the aging process, the molecular main chain of the peroxide-cured EPDM was broken, resulting in a double bond and C=O structure. When there is a coagent TAIC in the peroxide curing system, the presence of TAIC delays the degradation time of the EPDM molecular backbone, and the hydrolysis reaction of the TAIC crosslinking point occurs preferentially, which makes the stability of EPDM improved. In addition, regardless of the presence or absence of TAIC, the peroxide-cured EPDM undergoes a crosslinking reaction in the later stage of aging, resulting in an ether-crosslinked structure, thereby improving the damaged crosslinking network. Unlike the degradation of the peroxide curing system, the breakage of the molecular backbone does not occur in the sulfur-cured EPDM, but only an internal crosslinking reaction of the curing precursor occurs, resulting in a crosslinked network dominated by polysulfide bonds, thereby increasing the crosslinking density of the EPDM during the aging process.
研究领域:
材料科学
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高分子化学
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环境化学
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产品关联
DOI
高影响因子
EUROPEAN POLYMER JOURNAL
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2015
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IF 3.005
Tiankui Qiao,Ping Song,Huiling Guo,Xiaofeng Song,Baochang Zhang,Xuesi Chen
Biodegradable polymeric fiber membranes produced by electrospinning have been candidate for tissue engineering, but they sometimes lack the necessary mechanical stability. In the work, electrospun poly ( l -lactide) fiber membranes are chemically crosslinked by adding dicumyl peroxide (DCP) and triallylisocyanurate (TAIC). Their corresponding properties such as morphology, thermodynamics, mechanics, degradation and cytotoxicity are investigated. Morphology of PLLA fiber is maintained after crosslinking, but its crystallization and melting temperature is influenced by chemical crosslinking. The membranous tensile strength and modulus not only climb with TAIC concentration increasing, but also depend strongly on crosslinked temperature which the best is 140 °C. Compared to neat PLLA, degradation rate of the crosslinked PLLA membrane is slower. At the same time, it is also non-cytotoxic. The results suggest that the chemical crosslinking improves the mechanical properties of PLLA fiber membrane and keeps its mechanical stability longer, making it more suitable for tissue engineering.
研究领域:
材料科学
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生物材料
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组织工程
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产品关联
DOI
高影响因子
危险品化学品经营许可证（带存储）