MICROPOROUS AND MESOPOROUS MATERIALS
·
2020
·
IF 4.551
Jipeng Meng,Chuang Li,Xiao Chen,Chengye Song,Changhai Liang
Synthesis of highly-crystallized ZSM-48 zeolite with low SiO 2 /Al 2 O 3 ratio was successfully performed via seed-assisted route. The influence of various factors on the seed-assisted synthesis was investigated systematically, including the seeds dosages, different seeds species, adding order of seeds, hydrothermal temperature and time, silica and aluminum sources, and gel compositions. The crystallinity, morphology, textural and acidic properties of ZSM-48 were characterized by various techniques, such as XRD , SEM, FTIR, Py-IR, N 2 physisorption , 29 Si and 27 Al MAS NMR. Aluminum sources posed a critical influence on the crystallinity with NaAlO 2 more beneficial to obtain well-crystallized ZSM-48, whereas the crystallinity seemed slightly susceptible to silica sources. SEM results revealed that the crystal size was significantly reduced from ca. 20 μm to around 2 μm after introduced the seeds. Kinetic analysis suggested that the added seeds can significantly reduce the apparent activation energy of nucleation and crystallization, encourage the formation of crystal nuclei and promote crystallization. The Pt-supported seed-assisted samples exhibited considerably higher density of acid sites than that loaded on seed-free sample. The hydroisomerization of n -hexadecane was investigated over various Pt-supported catalysts, and the Pt-supported seed-assisted samples exhibited the highest i-C 16 yield of ca. 75 wt% at conversion over 87 wt%.
研究领域:
催化
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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
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2019
·
IF 3.771
Chao Lv,Ruiyang Wang,Jia Gao,Ning Ding,Shunni Dong,Jingjing Nie,Junting Xu,Binyang Du
Enhanced phase separation and inverse order-to-order phase transition with increasing temperature was observed for a series of poly (acrylic acid)- b -poly (propylene oxide)- b -poly (acrylic acid) triblock copolymers with various block lengths by temperature-variable synchrotron small-angle X-ray scattering (SAXS). This abnormal phase behavior was attributed to the change of hydrogen (H)-bonding interaction in block copolymers upon increasing temperature and theoretically explained from thermodynamic viewpoint. The temperature-dependent FTIR analysis revealed that increasing temperature led to the weakening of overall H-bonding interactions and the increase of free C O and C–O–C groups. The Flory-Huggins interaction parameter χ of PAA and PPO blocks was positive and increased with increasing temperature as determined from the SAXS profiles of disordered block copolymer. The thermodynamic calculation indicated that the increase of Δ H was larger than the decrease of – T Δ S with increasing temperature because of the relatively large value of χ , leading to the increase of overall Δ G mix and hence the enhanced phase separation at higher temperature.
研究领域:
高分子科学
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材料科学
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热力学
·
物理化学
✓ 已验证
DOI
高影响因子
POWDER TECHNOLOGY
·
2023
·
IF 5.2
Gege Huang,Hongjie Lin,Jinze Li,Jiankun Liu
Hydrophobized soils (or so-called artificial hydrophobic soils) are a novel geomaterial with a great potential in engineering applications due to its low affinity to water. For saline soils, hydrophobizing such soils can mitigate the soil salinization and subsequent engineering disasters such as salt expansion and corrosion by chlorides. To induce soil hydrophobicity , hydrophobic agents are widely used such as organo-silanes, fatty acids, and waxes. Correspondingly, the engineering properties and durability of these hydrophobized soils have been comprehensively investigated. However, all these studies focused on the clean mineral soils, i.e. , the soils without salts and in a moderate pH. For saline soils, the feasibility, stability and durability of these hydrophobic agents are unclear. This paper aims to propose suitable and feasible hydrophobic agents in hydrophobizing saline soils, by investigating its hydrophobicity change and having an insight into the mechanisms. The saline soils used were collected from Qinghai, China, and were treated by five different hydrophobic agents at different concentrations, with the hydrophobicity quantified by water drop penetration time, surface tension and contact angle. The soil hydrophobicity change was recorded after the treatment and wetting-drying cycles, in order to assess its stability and durability. Fourier transform infrared spectroscopy (FTIR), Raman spectrum and N 2 adsorption experiment were carried out to study the mechanism of soil hydrophobicity formation and degradation. The results showed two agents, namely Sodium methyl siliconate and Polymethylhydrosiloxane, provided the greatest and most durable hydrophobicity in saline soils. Their different formation mechanisms at particle- and nano-scale were also discussed. A further assessment on the soil mechanical properties revealed that both compaction behavior and strength were negligibly influenced by these two agents.
研究领域:
土木工程
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土壤学
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环境工程
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材料科学
✓ 已验证
DOI
高影响因子
JOURNAL OF SOLID STATE CHEMISTRY
·
2021
·
IF 3.498
Xiaoqing Xie,Yanfei Wang,Weini Zhou,Can Chen,Zeng Xiong
A new synthetic method was designed to prepare poly (trimesoyl chloride-co-polyethyleneimine) (PEI-TMC). Characterization of PEI-TMC was investigated by FTIR, SEM, EDS , XPS, TGA , and BET. TGA test revealed that the PEI-TMC had excellent thermal stability. The BET specific surface area (4.74 m 2 g −1 ) and pore diameter of about 9.44 nm indicated that PEI-TMC possessed a mesoporous structure. The adsorption behavior of U(VI) on the PEI-TMC was investigated. The thermodynamic analysis showed that the process of PEI-TMC adsorption of U(VI) was endothermic and spontaneous, and the adsorption efficiency was better at higher temperatures. The U(VI) sorption on PEI-TMC was conformed to the Langmuir adsorption isotherm and pseudo-second-order kinetic models . The adsorption mechanism of U(VI) with PEI-TMC was systematically elucidated by XPS and FTIR. Under the best condition, the maximum adsorption capacity of PEI-TMC could reach 212.8 mg g −1 by calculating the Langmuir isothermal model. It indicated that PEI-TMC was a potential adsorbent for the treatment of U(VI)-containing wastewater.
研究领域:
环境科学
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材料科学
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化学工程
✓ 已验证
DOI
高影响因子
CHEMOSPHERE
·
2021
·
IF 7.086
Liuting Mo,Yi Tan,Yulin Shen,Shifeng Zhang
Cellulose-based aerogels have considerable potential for various application due to renewable, low cost, and high availability. However, mechanical robustness and functionalization remain major challenges. Here, we synthesized a compressible, recoverable cellulose nanofiber (CNF)/carboxymethyl cellulose (CMC)/branched polyethyleneimine (BPEI) aerogel via electrostatic-modulated interfacial covalent crosslinking and freeze-drying process. The porous BPEI@CNF/CMC aerogel possessed excellent mechanical compression and high-density metal-chelating groups, which exhibited fast adsorption kinetics and high adsorption capacity (452.49 mg g −1 ) in static copper adsorption process. Furthermore, BPEI@CNF/CMC aerogels displayed excellent recyclability and could still reach 85% after 10 cycles. The integrated analyses of ATR-FTIR and XPS suggested that the predominant adsorption mechanism included electrostatic interaction, ion-exchange and chelation. This strategy provides a sustainable route to fabricate efficient biomass-based adsorbents for selective copper removal from water.
研究领域:
材料科学
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环境工程
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纳米技术
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化学工程
✓ 已验证
产品关联
DOI
PubMed
高影响因子
Polymers
·
2022
·Vol. 14
·期 21
·4682
·
IF 4.967
Xianxing Meng,Likun Wang,Hongwei Wang,Fang Zhang,Taying Su,Kunmu Cheng
Sulfonated phenol–formaldehyde (SPF) resin used as a cross-linker for petroleum reservoir conformance control was synthesized under alkaline conditions. The reaction process of SPF resin was evaluated by measuring the solution’s viscosity with respect to phenol–formaldehyde (PF) resin. The molecular structure of SPF resin was characterized by both FTIR and HPLC–MS/MS. The influence of the formaldehyde/phenol molar ratio (F/P) and the sodium formaldehyde sulfoxylate/phenol molar ratio (S/P) on the properties of SPF were analyzed in terms of the storage time, coagulation value, molecular size, and zeta potential. The results indicate that the presence of formaldehyde sodium bisulfite could slow down condensation reaction. Phenol rings were connected by methylene bridges in the position of o–p, and sulfonated SPF resin molecules all had one sulfonate group on the oligomer structure. The storage time decreased from 87 to 6 days, and the zeta potential decreased from −3.02 to −7.70 mV with the increase in F/P (1.2–2.0). Meanwhile, the sedimentation value and the diameter increased from 3.291 × 104to 5.045 × 104mg/L and from 2.7 to 5.3 nm, respectively. Sulfonation could significantly increase the storage time and dispersion stability. With the increase in S/P (0.1–0.35), the storage time increased from 15 to 86 days, the sedimentation value increased from 1.927 × 104to 5.269 × 104mg/L, and the diameter decreased from 6.3 to 3.0 nm. This paper can present new ideas for improving the storage stability and salt tolerance of phenol–formaldehyde resin and further improving the range of its applications, which has essential reference significance.Keywords:phenol–formaldehyde resin;sulfonation;characterization;HPLC–MS/MS
研究领域:
化学工程
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石油工程
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材料科学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
PROGRESS IN ORGANIC COATINGS
·
2023
·
IF 6.6
Qiuhua Xie,Zhihua Zhang,Na Li,Li Cui,Ping Wang,Yuanyuan Yu,Qiang Wang
In this study, transglutaminase-mediated alkylation modification of zein with octadecylamine (OA) was carried out to enhance the hydrophobicity of zein and the potential application of modified zein in the functionalization of textiles was evaluated. The reaction between OA and zein was demonstrated from the results of sodium dodecyl sulfate polyacrylamide gel electrophoresis (SDS-PAGE), Fourier transform infrared (FTIR) and 1 H nuclear magnetic resonance ( 1 H MIR). The hydrophobicity of zein significantly increased and the secondary structure of zein slightly changed after alkylation modification. The alkylated zein imparted excellent hydrophobic function to cotton textiles with a water contact angle (WCA) value of 131.7° and the hydrophobicity was long-lasting. Scanning electron microscope (SEM) showed a coarse surface formed on cotton fabric due to the participation of OA. The hydrophobic functionalization of the cotton fabric with alkylated zein did not cause negative impact on the mechanical properties and air permeability of the fabric.
研究领域:
材料科学
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纺织工程
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化学
✓ 已验证
产品关联
DOI
高影响因子
JOURNAL OF MOLECULAR LIQUIDS
·
2024
·
IF 5.3
Xier Gong,Jie Wang,Liying Bin,Weirui Chen,Ping Li,Pengran Guo,Zhiliang Chen,Bing Tang
The present study aimed to prepare an aluminum-based nanoflower (Al-NF) adsorbent using wasted aluminum polishing solution as raw materials, which effectively isolated the residues of anti-epidemic related drugs (lopinavir (LPV) and ciprofloxacin (CIP)) from wastewater. A comprehensive characterization approach involving SEM, XRD, BET, TGA, FTIR, and XPS was employed to investigate the adsorption capacity and mechanism of Al-NF towards LPV and CIP. The results revealed that the adsorption process involved both homogeneous and non-homogeneous interactions between the LPV/CIP molecules and the Al-NF surface. According to the Langmuir model calculations, the maximum adsorption capacities of Al-NF for LPV and CIP at 293.15 K were determined to be 32.41 mg/g and 14.43 mg/g, respectively, while their adsorption kinetics followed a pseudo-second-order model more appropriately. Furthermore, the spontaneous exothermic nature of LPV/CIP adsorption on Al-NF was confirmed by thermodynamic analysis. The mechanism investigations indicated that hydrogen bonding, electrostatic interaction, π-π bonding interaction, as well as n-π EDA bonding collectively contributed to the overall adsorption process on the Al-NF surface for both LPV and CIP species. Additionally, the reusability demonstrated by Al-NF highlights its potential as a promising low-cost material for removing anti-epidemic related drug residues from wastewater utilizing industrial hazardous wastes.
研究领域:
环境科学
·
材料科学
·
化学工程
·
废水处理
✓ 已验证
产品关联
DOI
高影响因子
SENSORS AND ACTUATORS B-CHEMICAL
·
2021
·
IF 7.46
Xueyan Wang,Baoyu Huang,Xiaofang Wu,Ding Gu,Xiaogan Li
Two-dimensional reduced graphene oxide (rGO) nanosheets were pre-sulfonated and further incorporated by WS 2 nanoflakes to form S-rGO/WS 2 heterojunctions by hydrothermal synthesis. The sulfonation and WS 2 incorporation in S-rGO/WS 2 heterojunction have been confirmed by EDS, XPS and FTIR. The sensing performance of rGO-based chemiresistive-type sensor to ammonia at room temperature has been significantly improved by the sulfonation and incorporation of WS 2 nanoflakes. The chemiresistive sensor based on S-rGO/WS 2 exhibits enhanced response signals to 10∼50 ppm ammonia, while the response/recovery time is significantly shortened compared to rGO/WS 2 reported previously at room temperature. It benefits from both the extra introduced active acid centers sensitive to ammonia molecules and the better desorption-ability facilitated significantly by sulfonate groups (S O 3 H). The adsorption energy calculation of ammonia molecule on the sulfonated graphene sheet based on density functional theory (DFT) has been performed to illustrate the adsorption capacity of S O 3 H group. The selectivity and stability of gas sensor based on S-rGO/WS 2 have also been studied.
研究领域:
材料科学
·
化学传感器
·
纳米技术
✓ 已验证
DOI
高影响因子
NEW JOURNAL OF CHEMISTRY
·
2020
·Vol. 45
·期 1
·123-130
·
IF 3.288
Wei Gao,Pingping Jiang,Qian Gu,Hong Zhang,Pingbo Zhang,Agus Haryono
A novel green plasticizer, acetylated lactic acid 1,6-hexane diester (ALHD), was successfully synthesized based on L-lactic acid, a renewable organic acid from corn starch. Its chemical structure was characterized using FTIR, 1H NMR and matrix-assisted laser desorption/ionization time of flight mass spectrometry (MALDI-TOF-MS). The plasticizing effects of ALHD as an alternative substitute for commercial plasticizer acetyl tributyl citrate (ATBC) in poly(vinyl chloride) (PVC) were investigated in detail. The results show that the PVC films plasticized using ALHD have better organic solvent resistance and food mimic migration stability than ATBC. After 24 hours of extraction in cyclohexane and petroleum ether, the weight loss of PVC sample S5 plasticized using pure ALHD was reduced by 83.6% and 77.5%, respectively, compared to that of PVC sample S1 plasticized with pure ATBC. Furthermore, after 72 hours of migration in activated carbon, the weight loss of PVC sample S5 decreased by 44.0% compared to that of PVC sample S1, which indicated that ALHD had excellent volatility and migration stability. The elongation at break of the PVC pieces increased from 644.65% to 802.15% as the content of ALHD improved, showing an increase of 24.4%. The mechanical property analysis showed that, with the replacement of ALHD in the place of ATBC, the PVC blends exhibited better flexibility and elasticity.
研究领域:
材料科学
·
化学
·
环境科学
·
高分子科学
✓ 已验证
产品关联
DOI
高影响因子
CARBOHYDRATE POLYMERS
·
2020
·
IF 7.182
Hao Wu,Shuqian Hu,Chunling Nie,Jiahui Zhang,Huafeng Tian,Weicheng Hu,Ting Shen,Jianguo Wang
Pathogens in the food and environment pose a great threat to human health. To solve this problem, we described a novel route to synthesize antibacterial epsilon-poly-L-lysine (EPL) anchored dicarboxyl cellulose beads. Cellulose beads were prepared via a sol-gel transition method and oxidized by sodium periodate and sodium chlorite to form carboxyl groups. EPL was anchored on the beads using carbodiimide mediated amidation. The structure and morphology of beads were characterized by FTIR, XPS, XRD, SEM, and TGA. After dissolution and regeneration, the crystalline form of cellulose is transformed from cellulose I to cellulose II. The thermal degradation temperature of the beads is 200∼300 °C.The samples displayed excellent antimicrobial activity against Staphylococcus aureus , Alicyclobacillus acidoterrestris and Escherichia coli within 12 h. The beads could be biodegraded in soil after 20 days. The biodegradable beads exhibited great potential in food and environmental applications.
研究领域:
材料科学
·
化学
·
生物技术
·
环境科学
·
食品科学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
JOURNAL OF MOLECULAR STRUCTURE
·
2022
·
IF 3.841
Yiqun Liu,Zhihao Chen,Xiaoshuang Yin,Yun Chen,Ying Liu,Wenzhong Yang
Arsenic pollution in natural water is a worldwide problem. In this work, a resin-based hydrated iron oxide (D303-HFO) adsorbent was designed to remove arsenate (As(V)) and arsenite (As(III)) in the groundwater. The structure and morphology of the D303-HFO adsorbent were characterized by FTIR, XRD , SEM and TEM tests. The specific surface area, pore volume and pore size increased with the incorporation of HFO nanoparticles in the resin. In addition, the effects of pH and coexisting ions on the arsenic removal efficiency were investigated. Results indicated that the D303-HFO had efficient removal performance for arsenic in the pH range of 3–9 and showed high selectivity for As(V) and As(III) under the influence of competitive ions. The adsorption kinetics study confirmed that the adsorption process was dominated by chemisorption , and the adsorption isotherms of As(V) and As(III) by D303-HFO fitted the Langmuir model. Thermodynamic parameters indicated that the adsorption reaction was spontaneous and exothermic. Moreover, the regeneration and stability experiment indicated that the D303-HFO adsorbent was super reusable after five consecutive cycles and could be put into service stably and permanently. The fixed-bed column test showed that the water sample containing As(V) and As(III) was treated with a volume of 900BV and 1100BV, respectively. After the treatment, the effluent concentration reached the drinking water standard stipulated by WHO.
研究领域:
环境科学
·
水处理
·
材料科学
✓ 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）