Journal of Environmental Sciences
·
2016
·
IF 2.208
Xingdu Chen,Chengjian Yang,Weiwei Wang,Bizhou Ge,Jun Zhang,Yucan Liu,Yaping Nan
The biodegradation characteristic and potential metabolic pathway for removal of environmental N,N-dimethylacetamide (DMAC) by Rhodococcus sp. strain B83 was studied. Rhodococcus sp. strain B83 was isolated from the rhizosphere of a pagoda tree and proved capable of utilizing DMAC as sole source of carbon and nitrogen. Batch culture studies showed that strain B83 could tolerate up to 25 g/L DMAC and showed distinct growth on possible catabolic intermediates except for acetate. The nitrogen balance analysis revealed that approximately 71% of the initial nitrogen was converted to organic nitrogen. DMAC degradation has led to accumulation of acetate and organic nitrogen, meanwhile traces of nitrate and ammonia was build-up but without nitrite. The growth of strain B83 could be inhibited by adding exogenous acetate. By means of the assay of enzymatic degradation of DMAC, several catabolic intermediates at different intervals were observed and identified. Based on the results obtained from culture solution and enzymatic degradation assay, a detailed pathway is proposed for DMAC biodegradation.
研究领域:
环境微生物学
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生物修复
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生物降解
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产品关联
DOI
PubMed
高影响因子
CARBOHYDRATE POLYMERS
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2019
·
IF 6.044
Quanqing Han,Xin Gao,Heng Zhang,Keli Chen,Lincai Peng,Qingmin Jia
In this study, cellulosic fines were separated from corn stalk soda-anthraquinone (AQ) pulp, then dissolved in DMAc/LiCl solvent system and regenerated to form films. Pulp fines was separated from pulp fibers using different standard sieves. The results exhibited that the value of specific surface area for fines was increased with the reduction of particle size. The cellulose of fines was successfully dissolved in DMAc/LiCl solution and regenerated as biopolymeric films in the water bath. Mechanical properties of regenerated cellulose films were enhanced with the increase of raw-material fineness from 120 to 300 mesh. It was exhibited a remarkable decrease on the values of tensile strength and maximum decomposition temperature of the regenerated cellulose film from 500-mesh fines, indicating that too small dimensions of cellulosic particles took disadvantages on physical strength and thermostability.
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DOI
高影响因子
Frontiers of Environmental Science & Engineering
·
2020
·Vol. 14
·期 6
·1-12
·
IF 4.053
Li Wenyue,Chen Min,Zhong Zhaoxiang,Zhou Ming,Xing Weihong
High-concentration industrial wastewater containing N,N -dimethylacetamide (DMAc) from polymeric membrane manufacturer was degraded in Cu 2 O NPs/H 2 O 2 Fenton process. In the membrane-assisted Fenton process DMAc removal rate was up to 98% with 120 min which was increased by 23% over the batch reactor. It was found that ·OH quench time was extended by 20 min and the maximum ·OH productivity was notably88.7% higher at 40 min. The degradation reaction rate constant was enhanced by 2.2 times with membrane dispersion ( k = 0.0349 min −1 ). DMAc initial concentration ( C 0 ) and H 2 O 2 flux ( J p ) had major influence on mass transfer and kinetics, meanwhile, membrane pore size ( r p ) and length ( L m ) also affected the reaction rate. The intensified radical yield, fast mass transfer and nanoparticles high activity all contributed to improve pollutant degradation efficiency. Time-resolved DMAc degradation pathway was analyzed as hydroxylation, demethylation and oxidation leading to the final products of CO 2 , H 2 O and NO 3 − (rather than NH 3 from biodegradation). Continuous process was operated in the dual-membrane configuration with in situ reaction and separation. After five cycling tests, DMAc removal was all above 95% for the initial [DMAc] 0 = 14,000 mg/L in wastewater and stability of the catalyst and the membrane maintained well.
研究领域:
环境科学
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化学工程
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DOI
高影响因子
ACS Omega
·
2020
·
IF 2.87
Panpan Zhang,Ke Zhang,Xi Chen,Shuliang Dou,Jiupeng Zhao,Yao Li
In this work, the effect of coagulation bath temperature in different solvent systems [1,4-butyrolactone (GBL)/N,N-dimethylacetamide (DMAC)] on the structure and dielectric properties of polyimide (PI) films was investigated for the first time. The solubility parameter was introduced to explain the formation process of porous PI films. The results showed that the changed tendency of the dielectric constant versus temperature is opposite for the single-solvent system and cosolvent system. For a single DMAC and GBL solvent, the dielectric constants of the films decreased with increasing temperature. In contrast, the dielectric constants increased with the increase in temperature for the GBL/DMAC cosolvent system. Moreover, the measured porosities were applied to estimate the dielectric constants of the PI films. This showed that the porosity increased with increasing temperature for a single-solvent system, while it decreased for a cosolvent system. Scanning electron microscopy images suggested that the variation trends are derived from the different influences of the temperature on the structure and morphology. Thus, this study reveals the effect of coagulation bath temperature on the structure and dielectric properties of porous PI films and provides the guidance for the design and optimization of architectures for high-performance porous films.
研究领域:
材料科学
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高分子化学
·
电气工程
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DOI
PubMed
高影响因子
ADVANCED FUNCTIONAL MATERIALS
·
2024
·Vol. 34
·期 51
·2410305
·
IF 18.5
Yang Song,Yongduo Liu,Daojun Long,Xiongxin Tao,Shijian Luo,Yuran Yang,Hao Chen,Meng Wang,Siguo Chen,Zidong Wei
Zinc metal has emerged as a promising candidate for high-capacity and low-cost anodes in aqueous zinc-ion batteries; nevertheless, it encounters serious obstacles, including low cycling stability and poor reversibility, caused by parasitic reactions and the formation of zinc dendrites. Herein, the study proposes a novel nonprotonic dimethylacetamide (DMAC)/ZnCl 2 /LiCl electrolyte that enables both solvation structural modulation of [ZnCl x ] 2-x and the cationic electrostatic shielding effect of [Li(DMAC)] + by controlling the concentration of LiCl. The optimal concentration of LiCl electrolyte (0.28 m ), which results in the highest ratio of [ZnCl 3 ] − , strikes a balance between low desolvation energy and a high mass transfer rate while promoting homoepitaxial deposition of Zn (002). Moreover, inert [Li(DMAC)] + ions, which possess a lower reduction potential, preferentially adsorb onto zinc protrusions, mitigating the tip effect. Leveraging electrolyte engineering, the zinc deposition/stripping process results in impressive long-term stability, surpassing 2,800 cycles, and the Zn||MnO 2 cell also achieves a stable lifespan extending beyond 1400 cycles. The research highlights the potential of LiCl as an additive in the modulation of water-free electrolytes.
研究领域:
电化学
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储能
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电池材料
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水系电池
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材料科学
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DOI
高影响因子
FIBERS AND POLYMERS
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2024
·Vol. 25
·期 5
·1713-1725
·
IF 2.2
Tan Lei,Bai Xiuzhi,Yao Rui,Fu Zengjin,Wang Jing,Wang Yicheng,Lin Tingrui,Hao Yan,Yang Hui,Yang Huimin,Sai Huazheng
The biodegradable biomass adsorbent (cellulose- g -PSS) was synthesized in LiCl/ N, N -dimethyl acetamide by the free-radical grafting polymerization reaction between sodium styrene sulfonate (SSS) and cellulose. Systematic optimization was conducted on many reaction parameters, including reaction time, monomer dosage, and reaction temperature. The grafting yield of cellulose- g -PSS was 50.16%. The chemical structures, physical, and chemical characteristics of cellulose- g -PSS were characterized by FTIR, SEM, PZC, 1 H NMR, XRD, TGA and XPS. An assessment was conducted to determine the sorption of Ce (III) on cellulose- g -PSS by changing the contact time, adsorbent dosage, pH, initial Ce (III) concentration, and NaCl concentration. The process of adsorption rapidly reached a state of equilibrium within a time frame of 25 min and was well explained using pseudo-second-order kinetic and Langmuir isotherm model. The maximum adsorption capacity for Ce (III) obtained from the Langmuir isotherm model was 84.80 mg·g −1 . The impact of NaCl concentration on the sorption of Ce (III) and XPS analysis showed that Ce (III) ions were adsorbed onto cellulose- g -PSS through ion-exchange mechanism. As a whole, cellulose- g -PSS exhibited great potential in rare earth wastewater treatment.
研究领域:
环境科学
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化学工程
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材料科学
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产品关联
DOI
高影响因子
BIOMACROMOLECULES
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2021
·
IF 6.988
Botuo Zheng,Songyi Xu,Xufeng Ni,Jun Ling
Polymerization of N-substituted glycine N-thiocarboxyanhydrides (NNTAs) is a promising pathway to prepare functional polypeptoids benefiting from their tolerance to nucleophilic impurities. However, controlled NNTA polymerization is hard to achieve in amide polar solvents, including N,N-dimethylacetamide (DMAc), N,N-dimethylformamide (DMF), and N-methyl pyrrolidone (NMP), the only aprotic solvents for many biomacromolecules and polypeptoids. In the present work, we successfully achieve controlled NNTA polymerization in amide polar solvents by adding acetic acid as a promoter. The promotion is applied to the polymerization of sarcosine NTA, N-ethyl glycine NTA, and N-butyl glycine NTA. DMAc, DMF, and NMP are suitable solvents to prepare polypeptoids with designable molecular weights and low dispersities (1.06–1.21). The polysarcosines with high molecular weights are prepared up to 35.2 kg/mol. A kinetic investigation quantitatively reveals that the presence of acetic acid not only accelerates the polymerization, but also suppresses H2S-catalyzed decomposition of NNTAs by decreasing the concentration of H2S dissolved in polar solvents. Benzoic acid is also able to promote the polymerization, while trifluoroacetic acid, phosphoric acid, and phenol are not appropriate promoters. The moderate acidity of acids is essential. l-Methionine, l-tryptophan, and l-phenylalanine, which are dissolved in DMF, initiate the controlled polymerization of sarcosine-NTA in the presence of acetic acid and introduce functional end groups to polysarcosines quantitatively. In DMAc, hydrophilic vancomycin is grafted by poly(N-butyl glycine). The amphiphilic product dissolves in dichloromethane and stabilizes water-in-oil emulsion.
研究领域:
高分子化学
·
材料科学
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生物技术
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DOI
高影响因子
危险品化学品经营许可证（带存储）