Materials Research Express
·
2025
·Vol. 12
·期 1
·015304
·
IF 2.2
Shibo Ren,Jianlin Xu,Lei Niu,Penghui Yang
In this study, the surface flame retardancy of polycarbonate (PC) was improved and the impact of flame retardants on the substrate were minimized by pre-mixing Al2O3 particles with dichloromethane, an infiltration promoter, to form a suspension, and then treating PC with the suspension to form an Al2O3 infiltration layer. For this layer, its structure and composition were characterized, its flame retardancy was evaluated, and its flame retardancy mechanism was investigated. The characterization results confirmed that an Al2O3 infiltration layer was successfully prepared on the PC surface under the aid of dichloromethane and that the involvement of dichloromethane induced certain microscopic pores and voids in the PC, with some dichloromethane remaining within the surface infiltration layer. The surface Al2O3 infiltration layer mainly served as a condensed-phase flame retardant. The infiltration layer prepared using a suspension with a dichloromethane-to-Al2O3 mass ratio of 24:1 not only exhibited a good overall performance but also achieved the best improvement in the PC flame retardancy, such as an increase in the vertical burning rating from HB to V-0, as well as the LOI increased from 24 to 31.3, and a 35% reduction in the peak heat release rate compared to those of pure PC.
研究领域:
材料科学
·
燃烧学
✓ 已验证
产品关联
DOI
高影响因子
Journal of Environmental Sciences
·
2025
·
IF 6.3
Shengyu Wu,Zhongran Wu,Guofeng Li,Yongkai Liao,Shanna Lin,Zhao Liu,Chao Cai
The transport behavior of pollutants under dynamic groundwater conditions has attracted significant attention recently. However, there is limited research on the simultaneous effects of groundwater table fluctuations on the transport of co-existing pollutants, especially combined dense and light non-aqueous phase liquids (DNAPLs and LNAPLs). In this study, column experiments investigated toluene and dichloromethane transport in a controlled water table system with varying fluctuation conditions. Results showed that both dichloromethane and toluene accumulated near the groundwater table under static water table conditions, but the concentration of dichloromethane declined more rapidly than toluene due to differences in their physicochemical properties, such as solubility, density, and hydrophobicity. Groundwater fluctuations facilitated pollutants transportation towards deeper layers, potentially resulting in unforeseen increases in pollutant volatilization and downward fluxes. The interactions between dichloromethane and toluene, including competitive adsorption, enhanced dissolution, and altered kinematic viscosities, resulted in the reduced transport potential of dichloromethane while enhancing that of toluene. Furthermore, compared to dichloromethane, the initial upward fluctuation of the water table had a more pronounced impact on toluene due to its lower solubility and volatility. The downward transport risk index assessment indicated that among various factors considered, groundwater fluctuation amplitude exerted the most significant influence on pollutant migration risk. These new findings will provide important insights into understanding and assessment of the potential transport risk associated with combined LNAPLs and DNAPLs in the natural environment.
研究领域:
环境科学
·
水文学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
INDUSTRIAL & ENGINEERING CHEMISTRY RESEARCH
·
2022
·
IF 4.326
Qiangbing Shi,Kaixuan Wang,Mengjun Wang,Tao Li,Baozeng Ren,Yinge Bai,Xiangping Zhang
Four sulfate-based ILs, 1-butyl-3-ethylimidazolium ethyl sulfate [Beim][EtSO4], 1-ethyl-3-ethylimidazolium ethyl sulfate [Eeim][EtSO4], 1-ethyl-3-methylimidazolium ethyl sulfate [Emim][EtSO4], and 1-ethylpyridinium ethyl sulfate [Epy][EtSO4], were synthesized and used as an absorbent for dichloromethane (DCM). Among them, the maximum DCM absorption capacity of 0.426 g DCM g–1 IL was achieved in [Beim][EtSO4] at 313.15 K and 37.7% DCM concentration, which was 42.2% higher than that of common organic solvent bis(2-ethylhexyl) adipate under the same conditions. The density and viscosity of [Beim][EtSO4] containing different mass fractions of DCM were measured. The density of [Beim][EtSO4] increases with the mass fraction of adsorbed DCM, while the viscosity decreases sharply. The efficient performance of ILs to absorb DCM is mainly due to the hydrogen bonding interaction between the anion and DCM, which was confirmed by spectroscopic measurement and quantum chemical calculations. This work demonstrates the great potential of ILs in separating and recovering DCM from exhaust gas.
研究领域:
化学工程
·
环境科学
✓ 已验证
产品关联
DOI
高影响因子
JOURNAL OF ENVIRONMENTAL MANAGEMENT
·
2024
·
IF 8
Shengyu Wu,Zhongran Wu,Suhang Wang,Youchi Zhang,Yongkai Liao,Chao Cai
The transport behavior of combined organic pollutants in soil and groundwater has attracted significant attention in recent years. Research on the influence of humic acid (HA) on organic pollutant transport behavior mainly focuses on the study of the mobile phase HA, with less research on the adsorbed phase HA, especially regarding its interaction with combined pollutants. To enhance understanding of the regulation of co-transport and retention of combined pollutants by adsorbed phase HA, in this study, tests were conducted to investigate how toluene (TOL) and dichloromethane (DCM) are transported in the presence of adsorbed phase HA at different pH levels and ionic strengths. As the proportions of HA-coated sand increased, so did its adsorption capacity for TOL and DCM, which can be attributed to adsorbed phase HA providing more adsorption sites compared to plain sand, thereby reducing the transport potential of the pollutants. The presence of both TOL and DCM facilitated their mutual transportation due to competitive adsorption controlled by the adsorbed phase HA content in the porous medium. Furthermore, it was observed that pH levels influenced the transport behavior of TOL and DCM when adsorbed phase HA was present since adsorbed phase HA transformation into mobile phase was regulated by pH levels. The transport patterns can be effectively simulated using the chemical nonequilibrium two-site sorption model in HYDRUS-1D, accurately reflecting the retardation coefficients and transport distances based on model parameters. This work sheds new light on the regulatory role of adsorbed phase HA in TOL and DCM transport under diverse hydrochemical conditions, with implications for accurately depicting the behavior of combined pollutants, optimizing the remediation strategies and improving remediation efficiency in contaminated sites.
研究领域:
环境科学
·
土壤学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
FUEL
·
2020
·
IF 5.578
Wenliang Wang,Xubiao Wang,Zhenhao Ma,Chao Duan,Shiwei Liu,Hailong Yu,Xinping Li,Liping Cai,Sheldon Q. Shi,Yonghao Ni
Lignin is considered as a renewable and sustainable resource for producing value-added aromatic chemicals and functional carbon materials. Herein, we develop a one-step catalyst-free depolymerization strategy to convert lignin into aryl monomers and carbon nanospheres simultaneously. Importantly, microwave-assisted depolymerization (MAD) in conjunction with dichloromethane (CH 2 Cl 2 ) vapors is developed. The total mass yield of guaiacols reached the highest amount of 225.1 mg/g at 600 °C, and the highest yields of phenols (49.0 mg/g) and aromatic hydrocarbons (155.1 mg/g) were obtained at 700 °C. Hydrogen radicals and hydrogen chloride (HCl) are in-situ formed from CH 2 Cl 2 , significantly decreasing the activation barrier and reforming pyrolysis vapors to promote the formation of aryl monomers. Interestingly, uniform carbon nanospheres with an average size of 140 nm were produced as co-products at 700 °C. The microwave “hot-spots”, allied with the continuous surface erosion and the decrease in surface energy of lignin-derived carbon precursors by CH 2 Cl 2 vapor, can be considered the driving force for the ultimate formation of carbon nanospheres. The CH 2 Cl 2 /MAD system produces aryl monomers (26.8 wt% yield) and carbon nanospheres (36.6 wt% yield) at 700 °C. We provide a facile, intriguing and scalable approach to convert lignin to valuable aryl monomers and sustainable carbon materials that can be applied in the chemistry, energy and environmental fields.
研究领域:
化学工程
·
材料科学
·
可再生资源利用
✓ 已验证
产品关联
DOI
高影响因子
INDUSTRIAL CROPS AND PRODUCTS
·
2019
·
IF 4.191
Cai Liang,Li Yang,Yu Shao,Xinyue Zhu,Hongliang Zhao,Biwei Chen,Wen Song,Xiangmin Song,Xiaofan Ding,Ranfeng Sun
The secondary metabolites produced by plants are important sources of fungicides with intriguing bioactivities and environmentally benign attributes (eg. low residual toxicity to mammals and readily biodegradable in soil). In this study, the dichloromethane extract of stems of Waltheria indica L. was found to exhibit broad-spectrum antifungal activity toward eight phytopathogenic fungi, particularly against carbendazim-resistant Sclerotinia sclerotiorum with inhibition rate of 100% at 500 μg/mL. Two quinoline alkaloids, antidesmone and waltherione C, were isolated and identified as fungicidal compounds by bioassay-guided isolation and spectroscopic analyses. Antidesmone displayed superior antifungal activities against eight phytopathogenic fungi to commercial botanical fungicides (osthole, carvacrol, and eugenol). Moreover, antidesmone was found to have significant negative cross-resistance with carbendazim to Sclerotinia sclerotiorum for the first time and exhibited much better antifungal activity (EC 50 = 0.60 μg/mL) against carbendazim-resistant strains than carbendazim-sensitive strain (EC 50 = 9.61 μg/mL) of Sclerotinia sclerotiorum , which was further supported by the molecular modelling result. In addition, the dichloromethane extract of the Waltheria indica stems could effectively control the development of eleven species of phytopathogenic fungi in vivo. These results suggest that Waltheria indica dichloromethane extract and antidesmone can be developed as promising broad-spectrum botanical fungicides.
研究领域:
植物学
·
真菌学
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农药科学
✓ 已验证
产品关联
DOI
高影响因子
RSC Advances
·
2014
·Vol. 4
·期 49
·25933-25939
·
IF 3.708
Qingfeng Liu,Yansen Zhang,Zhiguo Zhang,Tongxin Liu,Lei Shi,Guisheng Zhang
This paper describes a highly efficient and facile transformation of substituted oxazolidin-2-ones to methylene-bridged 3,3′-bis(oxazolidin-2-one) derivatives in a mixture solvent of CH2Cl2 (DCM) and N,N-dimethylformamide (DMF) in the presence of NaH at ambient temperature. Isotopic labeling experiments indicated that the C of the bridged methylene group was derived from CH2Cl2 instead of DMF and other unknown substances in the NaH reagent (60% dispersion in mineral oil).
研究领域:
有机化学
·
药物化学
✓ 已验证
产品关联
DOI
高影响因子
Nanoscale
·
2022
·Vol. 14
·期 42
·15724-15734
·
IF 8.307
Shaohua Chai,Shuangde Li,Le Zhang,Guijun Fan,Linfeng Nie,Xin Zhou,Wuxinchen Yang,Weiman Li,Yunfa Chen
The regulation of oxygen vacancies and Ru species using metal–organic frameworks was synergically adopted in a rational design to upgrade Ru/TiO2 catalysts, which are highly active for the catalytic oxidation of dichloromethane (DCM) with less undesired byproducts. In this work, Ru/M-TiO2 and Ru/N-TiO2 catalysts were synthesized by the pyrolysis of MIL-125 and NH2-MIL-125 incorporated with Ru, the existence of Ru nanoclusters and nanoparticles was detected by XAFS, respectively, and the catalytic performance was analyzed comprehensively. Complete oxidation of DCM was obtained at ∼290 °C over Ru/M-TiO2 and Ru/N-TiO2 catalysts, while Ru/N-TiO2 showed quite less monochloromethane (MCM) and higher CO2 yields, and better dechlorination capacity in oxidation. The distinction comes down to that the easier desorption of chlorine could be achieved over Ru4+ which act as the main activated adsorption sites for DCM in Ru/N-TiO2, compared to oxygen vacancies that serve as the main dissociation sites in Ru/M-TiO2. Additionally, Ru/N-TiO2 exhibited superior stability and excellent resilience in moisture. An in situ DRIFTS experiment further indicated the different DCM catalytic degradation process as well as the reaction mechanism over the as-prepared catalysts.
研究领域:
催化化学
·
环境科学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
JOURNAL OF CHEMICAL AND ENGINEERING DATA
·
2024
·
IF 2
Yutong Zhang,Yinge Bai,Mengjun Wang,Shaojuan Zeng,Wei Han,Xiangping Zhang
Ionic liquids (ILs) show great potential for the treatment of dichloromethane (DCM)-containing waste gases, but currently there are limited data on the vapor–liquid equilibrium (VLE) of DCM + IL systems. This work uses headspace gas chromatography (HS-GC) to determine the isothermal VLE data of the DCM + [Epy][EtSO4] and DCM + [Emim][EtSO4] systems at 308.15 K, 313.15 K, 318.15 K, 323.15 K, and 328.15 K. The nonrandom two-liquid (NRTL) and universal quasi-chemical correlation activity coefficient (UNIQUAC) models are used to regress the VLE data. The results show that the fitting average relative deviations (ARDs) of the DCM + [Epy][EtSO4] and DCM + [Emim][EtSO4] systems to the NRTL model were 6.97% and 7.95% and the fitting ARDs to the UNIQUAC model were 6.10% and 6.28%, respectively. The fitting effects of the UNIQUAC models for both systems were better than those of the NRTL model. With the models, the calculated activity coefficients of DCM were all less than 1, indicating that the solutions exhibited negative deviations from Raoult’s law, and the nonideality of the solutions increased with increasing IL concentration.
研究领域:
化学工程
·
环境科学
✓ 已验证
DOI
高影响因子
Frontiers of Environmental Science & Engineering
·
2019
·Vol. 13
·期 2
·1-12
·
IF 3.883
Deng Yuzhou,Peng Shengpan,Liu Haidi,Li Shuangde,Chen Yunfa
Mesoporous TiO 2 was synthesized via nonhydrolytic template-mediated sol-gel route. Catalytic degradation performance upon dichloromethane over as-prepared mesoporous TiO 2 , pure anatase and rutile were investigated respectively. Disproportionation took place over as-made mesoporous TiO 2 and pure anatase under the presence of water. The mechanism of disproportionation was studied by in situ FTIR. The interaction between chloromethoxy species and bridge coordinated methylenes was the key step of disproportionation. Formate species and methoxy groups would be formed and further turned into carbon monoxide and methyl chloride. Anatase (001) played an important role for disproportionation in that water could be dissociated into surface hydroxyl groups on such structure. As a result, the consumed hydroxyl groups would be replenished. In addition, there was another competitive oxidation route governed by free hydroxyl radicals. In this route, chloromethoxy groups would be oxidized into formate species by hydroxyl radicals transfering from the surface of TiO 2 . The latter route would be more favorable at higher temperature.
研究领域:
催化化学
·
材料科学
·
环境科学
✓ 已验证
产品关联
DOI
高影响因子
DYES AND PIGMENTS
·
2022
·
IF 5.122
Zhizhou Liu,Chao Li,Chen Chen,Tong Wang,Liang He,Xueyan Nan,Li Li,Qing Qian,Pengli Bai
In this paper, a lophine-based phenol compound has been prepared and identified as an efficient chromophore for the determination of hydrogen peroxide (H 2 O 2 ) with enzymatic method. A dry chemistry analytic agent was also prepared involving this compound, showing good accuracy in the determination of uric acid. However, a commonly used solvent dichloromethane (DCM) could react with this imidazole derivative when the reaction mixture was irradiated under UV (365 nm). We explored the possible mechanism and identified several by-products caused by the acidity and ultraviolet oxidation of DCM. Caution should be taken in the synthesis and application of such imidazole-based dyes in DCM, especially when phenol group was introduced to the imidazole moiety.
研究领域:
分析化学
·
有机化学
✓ 已验证
产品关联
DOI
高影响因子
COLLOIDS AND SURFACES A-PHYSICOCHEMICAL AND ENGINEERING ASPECTS
·
2023
·
IF 5.2
Qingqing Yang,Yizhen Bian,Guobin Ren,Minghuang Hong
In the process of preparing microspheres by evaporation of emulsion, drug transfer in the system makes it difficult to control the drug loading and encapsulation efficiency of the product. In this study, Nimodipine loaded microspheres were prepared using poly(lactic-co-glycolic acid) (PLGA) as the matrix materials . The transfer process of drug molecules and solvent molecules in the preparation process were observed by online imaging. Combined with weighing experiments and molecular simulation , three stages of dichloromethane (DCM) diffusion in oil phase were proposed. At 20 °C,15 % and 46 % of DCM content were taken as the critical point, and between the content was slow volatilization stage, which dominated the occurrence of drug reflux and crystallization. The oil phase diffusion and emulsion mass transfer equations of DCM were proposed to judge the influence of each single factor on drug molecular transfer. Low temperature, oil-water ratio and stirring speed could slow down the volatilization of DCM and increase the drug loading and encapsulation efficiency. Low stirring speed could increase the drug loading while avoiding crystallization and reflux, which was the best control factor.
研究领域:
药剂学
·
生物医学工程
✓ 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）