JOURNAL OF APPLIED POLYMER SCIENCE
·
2021
·Vol. 138
·期 45
·51348
·
IF 3.125
Junming Chen,Jinxuan He,Longquan Liu,Yongzhu He,Xiaobin Huang
Polymeric ablative materials (PAMs) are widely used in spacecraft currently for thermal insulation. However, it is challenging to find a single filler that can improve both ablative and mechanical properties of PAMs. In this study, a new type of hybrid cross-linked polyphosphazene microspheres (PHC) is added to ethylene propylene diene monomer (EPDM) composites as a filler for the first time and its influence on the ablation, mechanical, and thermal properties of EPDM is investigated. The results show that the addition of 3 phr PHC increases the ablation performance by about 10% and enhances the mechanical properties by 20% approximately. In addition, the ablation mechanism is studied in accordance with SEM, FTIR, and Raman spectroscopy. On the one hand, PHC has the effect of catalyzing carbonization, thus increasing the rate of residual carbon; on the other hand, PHC changes the morphology of the char layer, forming a cross-linked structure containing P─O─Si bonds on the surface. The findings regarding catalyzing carbonization and the special char layer structure could guide the design of ablative materials.
研究领域:
高分子材料
·
航天热防护
·
复合材料科学
·
材料化学
·
热力学
✓ 已验证
DOI
高影响因子
JOURNAL OF AGRICULTURAL AND FOOD CHEMISTRY
·
2023
·
IF 6.1
Rong Zeng,Xiuxiu Zou,Cong Huang,Hongyan Si,Jie Song,Ji Zhang,Hai Luo,Zongde Wang,Peng Wang,Guorong Fan,Xiaoping Rao,Shengliang Liao,Shangxing Chen
Although much progress has been made in developing botanical fungicides to combat fungal diseases in crops, there remains a great need to improve the efficiency and long-term safety of these fungicides. This study proposes a novel strategy for designing citral-thiourea derivatives that feature such desirable properties. The motivation of the work herein was to enhance the antifungal activity of citral against C. gloeosprioides by exploiting the synergistic effect that arises from combining citral and thiourea compounds, thereby producing citral-thiourea derivatives that exhibit good long-term safety. The results revealed that the generated compounds e1, e3, e6, e18, and g showed remarkable antifungal activities against C. gloeosprioides, with corresponding EC50 values reaching 0.16, 1.66, 1.37, 4.76, and 4.60 mg/L, respectively, showing that the compounds significantly outperformed both the positive control kresoxim-methyl and the commercially available fungicide carbendazim. Furthermore, compound g showed stronger protective efficacy against C. gloeosprioides than carbendazim on mango fruit at 25 mg/L. Investigating the preliminary structure–activity relationship (SAR) of the compounds also revealed that the citral-thiourea derivatives exhibited higher antifungal activities against C. gloeosprioides compared to citral and thiourea compounds. This reinforcement of antifungal activity observed in the derivatives was found to be attributable to the two characteristics of low molecular size and the presence of a fluorine atom in the meta-position of the benzene ring. Beyond this, it was determined from QSAR that two molecular descriptors (the Kier–Hall index (order 3) and Tot dipole of the molecules) were negatively related to the antifungal activity of the citral-thiourea derivatives, while one other (the maximum resonance energy of a C–H bond) was positively related to their antifungal activity. More importantly, the citral-thiourea derivatives with high antifungal activities (i.e., compounds e1, e3, e6, e14, e15, e18, and g) exhibited negligible cytotoxicity to LO2 and HEK293T cell lines. The antifungal mechanism of the generated citral-thiourea derivatives was investigated by scanning electron microscopy (SEM) and relative conductivity. The derivatives were found to affect mycelial morphology and increase fungal cell membrane permeability, thereby resulting in the destruction of fungal cell membranes. These promising results provide novel insights into the study and potential application value of citral-thiourea derivatives as high-efficiency antifungal agents against C. gloeosprioides.
研究领域:
植物保护
·
药物化学
✓ 已验证
DOI
PubMed
高影响因子
SCIENCE OF THE TOTAL ENVIRONMENT
·
2019
·
IF 5.589
Xin Huang,Dong Wei,Xinwen Zhang,Dawei Fan,Xu Sun,Bin Du,Qin Wei
In the present study, a novel amino-functionalized magnetic aerobic granular sludge-biochar (NH 2 -M-AGS) was successfully fabricated through magnetization and functional modification and applied for Pb(II) sorption . The composite was characterized by using scanning electron microscopy (SEM), energy dispersive spectrum (EDS), Fourier transform infrared spectroscopy (FTIR), X-ray diffraction (XRD), Zeta potential analysis, vibrating sample magnetometer (VSM) and X-ray photoelectron spectroscopy (XPS). The effects of adsorbent dosage, pH value, contact time and initial metal concentration on the adsorption of Pb(II) were investigated by using batch equilibrium experiments. It was concluded that the pseudo-second-order model was better to describe adsorption kinetic of Pb(II) onto NH 2 -M-AGS. The Langmuir model was more accorded with the experimental data, and the maximum adsorption capacity of Pb(II) was 127.0 mg/g. A possible adsorption mechanism could be mainly caused by surface complexation, electrostatic attraction and precipitation. In five adsorption-desorption cycles, the desorption efficiency of Pb(II) exhibited a slight decline and still reached at 88.14%. Furthermore, the good reproducibility indicated that NH 2 -M-AGS could be used a desirable, economic and recyclable adsorbent in practical metal-contaminated wastewater treatment .
研究领域:
环境科学
·
材料科学
✓ 已验证
DOI
高影响因子
Journal of Materials Chemistry A
·
2019
·Vol. 7
·期 12
·6849-6858
·
IF 10.733
Xiao-Hu Dai,Hao-Xiang Fan,Chun-Yan Yi,Bin Dong,Shi-Jie Yuan
Nanoscale zerovalent iron (nZVI) and its composite materials have extensive applications in the field of environmental remediation. 3D nZVI/biochar composite materials have been prepared and reported, but the development of facile, environmentally friendly methods to produce 2D nZVI/biochar composites remains challenging. This study describes a facile solvent-free carbothermal redox approach to preparing graphene oxide-like 2D biochar stabilized nZVI with a shearing/carbonization method that uses lignocellulosic waste, old corrugated containers (OCCs), and FeCl3·6H2O as precursors. The association of a shear exfoliation/carbonization process with the deliquescence characteristic of FeCl3·6H2O and the catalysis of Fe3+ and Cl− resulted in the dispersion of Fe3+ phases into the OCC frameworks and the formation of an intrinsic graphene oxide-like 2D structure. In addition to the conventional carbothermal reduction of Fe species to nZVI by carbon, a simultaneous oxidation of the C–O groups inside the biochar to CO groups, which could catalyze peroxymonosulfate (PMS) decomposition to generate 1O2, was also discovered. The as-synthesized 2D ZVI/biochar exhibited high catalytic activity and recyclability toward the degradation of bisphenol A (BPA) by activating either PMS or H2O2 under near-neutral pH conditions. The excellent catalytic activity of the as-synthesized ZVI/biochar can be ascribed to the synergetic effect of the Fe0 species, the ketonic CO groups, and the intrinsic graphene oxide-like 2D structure, which act as excellent electron transfer supports. The as-synthesized 2D nZVI/biochar exhibited excellent long-term stability without significant loss of activity after storage in air for 6 months. This study not only provides a simple, green solvent-free approach to the sustainable manufacture of graphene oxide-like biochar stabilized nZVI as a highly efficient and durable bi-functional catalyst, but also suggests new possibilities for the further design and fabrication of 2D nZVI composite materials.
研究领域:
环境科学
·
材料科学
✓ 已验证
DOI
高影响因子
MEAT SCIENCE
·
2021
·
IF 5.209
Huan Liu,Teng Hui,Fei Fang,Shaobo Li,Zhenyu Wang,Dequan Zhang
The formation of key aroma compounds in roasted mutton during the traditional charcoal process were investigated. The results indicated that the samples roasted for 0–15 min could be discriminated using a flash GC E -nose and GC-O-MS combined with multivariate data analysis. A total of 37 odorants were identified, among which 15 odorants were confirmed as key aroma compounds by aroma recombination experiments. Significant increases in key aroma compositions and concentrations in samples were observed during the roasting process, in which hexanal had the highest concentration. The odour activity values (OAVs) of 15 key aroma compounds were maintained at high levels in the samples after roasting for 10 min. The roasted mutton had typical aromas of meaty, fatty, roasty, grassy, and sweet odours. The multivariate linear modeling indicated that a lower specific heat capacity and lower water activity could contribute to the formation of aroma compounds of samples.
研究领域:
食品科学
·
化学
✓ 已验证
DOI
PubMed
高影响因子
NANOTECHNOLOGY
·
2023
·Vol. 35
·期 2
·025706
·
IF 3.5
Meilin Wang,Yaoxin Li,Jiaoxing Xu,Lunhui Guan
Two-electron oxygen reduction reaction (2e− ORR) for H2O2 production is regarded as a more ecologically friendly substitute to the anthraquinone method. However, the search of selective and cheap catalysts is still challenging. Herein, we developed a neutral-selective and efficient nonprecious electrocatalyst that was prepared from a commercial activated carbon (AC) by simply microwave-assisted ash impurity elimination and hydrogen peroxide oxidation for surface functional sites optimization. The oxygen configuration can be tuned with enriching carboxyl group up to 6.65 at.% by the dosage of hydrogen peroxide (mass ratio of H2O2/C = ∼0–8.3). Chemical titration experiments identified the carbonyl groups as the most potential active sites, with selectivity boosted by the additional carboxyl groups. The microwave-assisted moderate-oxidized activated carbon (MW-AC5.0) demonstrated optimal 2e− ORR activity and selectivity in neutral electrolyte (0.1 M K2SO4), with H2O2 selectivity reaching ∼75%–97%, a maximum H2O2 production rate (1.90 mol·gcatal−1·h−1@0.1 V) and satisfying faradaic efficiency (∼85%) in gas-diffusion-electrode. When coupled with Fenton reaction, it can degrade a model organic pollutant (methylene blue [MB], 50 ppm) to colorless in a short time of 20 min, indicating the potential applications in the environmental remediation.
研究领域:
环境科学
·
材料科学
✓ 已验证
DOI
高影响因子
BIOLOGICAL CONTROL
·
2018
·
IF 2.112
Yi Zhou,Wen Li,Jiaoke Zeng,Yuanzhi Shao
The yeast Debaryomyces nepalensis was evaluated for effectiveness against Colletotrichum gloeosporioides in mangoes ( Mangifera indica L.) cv. ‘Tainong No. 1’, and possible mechanisms of action involved in the inhibition were identified. The results showed that D. nepalensis could survive in mango wounds and produce a hydrolytic enzyme (β-1,3-glucanase). Scanning electron microscopy showed that the yeast produced biofilms on the mango surface and yeast cells attached to each other and became embedded in the pathogen hyphal walls. In addition, D. nepalensis competed for nutrients (FeCl 3 ) and competed for space with the pathogen (p < 0.05). Morever, D. nepalensis enhanced defense-related enzymes of wounded mangoes, including peroxidase, β-1,3-glucanase, chitinase and phenylalanine ammonia-lyase. In addition, gas chromatographic-mass spectrometry (GC–MS) analysis of volatile compounds (VOCs) produced by the yeast showed that VOCs can play important roles over short distances in the suppression of C. gloeosporioides. The solid-phase microextraction (SPME) coupled with GC–MS technique analysis revealed phenylethyl alcohol (29.62% relative peak area, RA) as the dominant VOC mainly produced by D. nepalensis , and it had a significant inhibitory effect on fungal mycelia. According to the results obtained here, the combination of different mechanisms of action of the yeast increases their ability to control C. gloeosporioides. The use of antagonistic yeast to control C. gloeosporioides may contribute to the integrated management of disease caused by this pathogen.
研究领域:
植物病理学
·
食品科学
·
微生物学
✓ 已验证
DOI
高影响因子
RSC Advances
·
2014
·Vol. 4
·期 98
·55256-55262
·
IF 3.708
Zhijian Wu,Ya Xiong,Guoqiang Guan,Lingjun Kong,Shuanghong Tian
A new pyrolytic process was successfully used to prepare hollow-like spherical sludge chars (HSC). In the process, pre-formed cotton spheres with a low density were firstly coated by a layer of sludge paste containing ZnCl2 to form cotton fiber@sludge spheres and then pyrolyzed at 500 °C for 2 h. The resulting HSC possessed a diameter of about 3 mm, a low density of 0.1008 g cm−3 and a high surface area of 1008 m2 g−1. The column adsorption behavior showed that the adsorption capacity and rate constant of HSC for methylene blue reached 186.4 mg g−1 and 0.232 mL min−1 mg−1. The adsorption capacity is about 8.4 and 12 fold of the adsorption capacities of GAC (22.28 mg g−1) and SC (15.26 mg g−1), respectively, and the adsorption rate constant is about 1.3 fold of that of GAC and SC. The great adsorption capacity and rate constant can be considerably dependent on the special hollow-like spherical structure of HSC.
研究领域:
环境科学
·
材料科学
·
化学工程
·
污染控制
·
吸附技术
✓ 已验证
DOI
高影响因子
JOURNAL OF ALLOYS AND COMPOUNDS
·
2020
·
IF 4.65
Guohua Fan,Yuliang Jiang,Chuanxin Hou,Xuanru Deng,Zixuan Liu,Lujie Zhang,Zidong Zhang,Runhua Fan
The green chemistry strives for desired products with sustainable approaches and no using hazardous stuff. Recently magnetic carbon composite absorbers have attracted much attentions for military and civil applications. In this work, an extremely facile and green method of carbonizing metal-precursor impregnated bulrush was proposed to fabricate Co/C and Ni/C nanocomposites for wave-absorbing. The synergistic effect of dielectric loss from carbon biochar and magnetic loss from Co/Ni components, as well as the optimized impedance matching properties and elevated attenuation capabilities, contributed to the excellent absorption performance of Co/C and Ni/C nanocomposites. The minimum reflection loss for Co/C and Ni/C absorbers were −52.42 dB (with thickness of 1.93 mm) and −50.98 dB (with thickness of 2.52 mm), respectively. The widest bandwidth of effective absorbing for Co/C was 4.29 GHz with a thickness only 1.44 mm, and that for Ni/C was 4.47 GHz at 1.57 mm. This work provided a facile way for the mass production of magnetic carbon absorbers through recycling abundant natural plant waste from the point of green chemistry.
研究领域:
材料科学
·
环境化学
·
纳米复合材料
·
绿色化学
·
电磁功能材料
✓ 已验证
DOI
高影响因子
Desalination and Water Treatment
·
2024
·
IF 1
Tingting Zhang,Yanling Yang,Xing Li,Nan Wang,Hang Li,Peng Du,Haikuan Yu,Siyang Ji,ZhiweiZhou
In this study, an experimental study aimed at optimizing the factors affecting the regeneration amount of 4-chlorophenol (4-CP) from spent powdered activated carbon (PAC) is presented. For this response surface methodology (RSM) with Box-Behnken design was applied, which identified four variables (acoustic density, NaOH concentration, spent PAC dosage and ethanol concentration) in batch experiments. The physicochemical characteristics of the regenerated PAC under the optimal desorption condition was evaluated using thermogravimetric analysis, Fourier transform infrared spectroscopy (FTIR), Brunauer-Emmett-Teller (BET) and scanning electron microscopy, as compared with the virgin and spent PACs. Among the four variables, acoustic density and ethanol concentration (v/v, %) had stronger effect on the 4-CP desorption (p < 0.001). The predicted optimal 4-CP desorbing amount was 97.43 mg g –1 , and this matched well the observed performance of (96.94 ± 0.70) mg g –1 , obtained by acoustic density of 0.36 W mL –1 , NaOH concentration of 0.10 mol L –1 , spent PAC dosage of 0.93 g L –1 and ethanol concentration (v/v) of 24%. The result of thermogravimetric pyrolysis profiles of regenerated PAC confirmed that the adsorption behavior of 4-CP exhibited a chemisorption feature and desorption process was dominated by chemical reaction. Analysis of FTIR, pore structure and BET surface area demonstrated that ultrasound mainly acted on the surface functionalities, macro-pore and meso-pore structure of PAC. Additionally, the SEM images indicated that cavitation effect affected the surface roughness and surface cavities of PAC. The results here provided an insight into the application of ultrasound to regenerate saturated PAC with 4-CP.
研究领域:
环境工程
·
吸附与再生
·
水处理技术
·
物理化学方法
·
环境污染控制
✓ 已验证
DOI
高影响因子
JOURNAL OF HAZARDOUS MATERIALS
·
2020
·
IF 9.038
Xiaohong Guan,Xueying Du,Meichuan Liu,Hejie Qin,Junlian Qiao,Yuankui Sun
Given that there are still some debates on the influence of carbon modification on zerovalent iron (ZVI) decontamination process, the roles of carbon on trichloroethylene (TCE) reduction by ZVI were re-investigated in this work. Compared to activated carbons (AC) with high adsorption ability, carbon fibers (CF) with good electronic conductivity performed much better in enhancing ZVI performance in terms of both reactivity and selectivity. Moreover, it was interesting to observe that a low carbon loading is sufficient to effectively improve TCE reduction and this promoting effect would decline with further increasing the carbon amounts from 1.0 wt.% to 50 wt.%. Regarding to the ZVI selectivity, a relatively high carbon loading (especially for CF, it may be as high as 50 wt.%) was needed to protect ZVI from non-productive reactions with H 2 O/H + effectively. However, a mixture of 10 wt.% AC and 1.0 wt.% CF could combine their respective merits of inhibiting side reactions and enhancing TCE reduction, and thus simultaneously enhanced the reactivity and selectivity of ZVI. Mechanistic investigations revealed that carbon modification could enhance the ZVI performance through improving TCE adsorption and/or accelerating electron transfer, while the latter one may play a more important role especially at high carbon loadings.
研究领域:
环境科学
·
化学工程
·
材料科学
✓ 已验证
DOI
高影响因子
CELLULOSE
·
2024
·Vol. 31
·期 4
·2667-2683
·
IF 4.9
Zhao Jieyun,Xiao Mengyuan,Jiang Lina,Ren Yuanlin,Liu Xiaohui
To endow lyocell fabric with flame retardant and antibacterial properties, tri (2-hydroxyethyl) isocyanurate was utilized to synthesize a phosphorus and nitrogen-containing flame retardant (ATHEIC), which was then used to prepare flame retardant lyocell fabric (FR-lyocell). The antibacterial properties of FR-lyocell were achieved by adsorbing copper ions on the fabric surface followed by reducing to copper nanoparticles. The lyocell fabric treated with 30 wt% ATHEIC solution possessed an LOI value of 35.8%, which remained 31.9% even after 20 laundering cycles. The char residue at 800 °C of FR-lyocell under nitrogen and air atmosphere was 48.6 wt% and 27.3 wt%, respectively, indicating excellent char forming performance. Antibacterial tests showed that the modified lyocell fabric had a bacteriostatic zone width of 5.3 mm and 4.6 mm against E . coli and S . aureus, respectively. This work provides a new approach to fabricate multifunctional lyocell fabric with flame retardant and antibacterial properties.
研究领域:
纺织科学
·
高分子科学
·
纳米技术
·
消防安全工程
·
微生物学
✓ 已验证
DOI
高影响因子
危险品化学品经营许可证（带存储）