CERAMICS INTERNATIONAL
·
2020
·Vol. 46
·期 13
·20810-20818
·
IF 3.83
Mengjing Liu,Sun-Wai Chiang,Xiaodong Chu,Jia Li,Lin Gan,Yanbing He,Baohua Li,Feiyu Kang,Hongda Du
Herein, oriented boron nitride (BN)/alumina (Al 2 O 3 )/polydimethylsiloxane (PDMS) composites were obtained by filler orientation due to the shear-inducing effect via 3-D printing. The oriented BN platelets acted as a rapid highway for heat transfer in the matrix and resulted in a significant increase in the thermal conductivity along the orientation direction. Extra addition of spherical Al 2 O 3 enhanced the fillers networks and resulted in the dramatic growth of slurry viscosity. This, together with filler orientation induced the synergism and provided large increases in the thermal conductivity . A high orientation degree of 90.65% and in-plane thermal conductivity of 3.64 W/(m∙K) were realized in the composites with oriented 35 wt% BN and 30 wt% Al 2 O 3 hybrid fillers. We attributed the influence of filler orientation and hybrid fillers on the thermal conductivity to the decrease of thermal interface resistance of composites and proposed possible theoretical models for the thermal conductivity enhancement mechanisms.
研究领域:
材料科学
·
高分子化学
·
热管理材料
·
先进制造
·
复合材料工程
✓ 已验证
DOI
高影响因子
Journal of Environmental Sciences
·
2017
·
IF 2.865
Yanfeng Wang,Wei Chen,Xiao Chen,Huajun Feng,Dongsheng Shen,Bin Huang,Yufeng Jia,Yuyang Zhou,Yuxiang Liang
CdS/MoS 2 , an extremely efficient photocatalyst , has been extensively used in hydrogen photoproduction and pollutant degradation . CdS/MoS 2 can be synthesized by a facile one-step hydrothermal process. However, the effect of the sulfur source on the synthesis of CdS/MoS 2 via one-step hydrothermal methods has seldom been investigated. We report herein a series of one-step hydrothermal preparations of CdS/MoS 2 using three different sulfur sources: thioacetamide, l -cysteine, and thiourea . The results revealed that the sulfur source strongly affected the crystallization, morphology, elemental composition and ultraviolet (UV)–visible-light-absorption ability of the CdS/MoS 2 . Among the investigated sulfur sources, thioacetamide provided the highest visible-light absorption ability for CdS/MoS 2 , with the smallest average particle size and largest surface area, resulting in the highest efficiency in Methylene Blue (MB) degradation. The photocatalytic activity of CdS/MoS 2 synthesized from the three sulfur sources can be arranged in the following order: thioacetamide > l -cysteine > thiourea . The reaction rate constants ( k ) for thioacetamide, l -cysteine, and thiourea were estimated to be 0.0197, 0.0140, and 0.0084 min −1 , respectively. However, thioacetamide may be limited in practical application in terms of its price and toxicity, while l -cysteine is relatively economical, less toxic and exhibited good photocatalytic degradation performance toward MB.
研究领域:
材料科学
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环境化学
·
纳米催化
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光催化
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无机功能材料
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能源材料
✓ 已验证
DOI
高影响因子
JOURNAL OF APPLIED POLYMER SCIENCE
·
2019
·Vol. 136
·期 27
·47723
·
IF 2.188
Yayun Zheng,Yaofang Hu,Xing Yang,Meng Yuan,Jie Zhang,Yaodong Zhang,Jujie Luo
We synthesized novel polyurethane (PU) membranes from isophorone diisocyanate (IPDI), poly(ethylene glycol) (PEG) with a molecular weight of 2000, aminopropyl-terminated poly(dimethyl siloxane) (PDMS) with a molecular weight of 2000, and 1,4-butanediol (BDO) via a two-step polymerization. The structure of each synthesized membrane was studied through Fourier transform infrared spectroscopy and gel permeation chromatography. The effect of the thermal behavior was determined by differential scanning calorimetry and thermogravimetric analysis. The gas-permeability characteristics of the PU membranes were then tested for a single gas. The results show that the permeability of CO 2 ( P CO2 ) gradually increased with PDMS content. Among these PU membranes, PU-d (PEG/PDMS = 1:1, PEG/PDMS/IPDI/BDO = 1:3:2) showed the best P CO2 (132.6 Barrer) at 25°C and 1 bar pressure. The gas-permeability coefficients of each PU membrane at different operating temperatures were investigated, and the results show that P CO2 reached 302.6 Barrer at 65°C and 1 bar. © 2019 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2019 , 136 , 47723.
研究领域:
高分子材料科学
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膜分离技术
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气体分离
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功能高分子
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环境化工
✓ 已验证
DOI
高影响因子
Journal of the Taiwan Institute of Chemical Engineers
·
2019
·
IF 3.834
Yunlei Zhang,Bing Li,Yanan Wei,Changhao Yan,Minjia Meng,Yongsheng Yan
Developing a green and economically viable approach for the direct synthesis of metal-organic frameworks (MOFs) catalysts with multifunctional active sites remains the key step for their applications in heterogeneous catalysis field. Herein, we report a green (aqueous solutions), mild (90 °C, atmospheric pressure), and modulated hydrothermal (MHT) approach to synthesize UiO-66-type MOFs catalysts with acid–base bi-functional sites, which were obtained via the coordination of monosodium 2-sulfoterephthalate and 2-aminoterephthalic with zirconium (Zr) ions. More importantly, a series of acid, base and acid–base catalysts with varied acid–base strengths can be readily prepared, by simply varying the ratio of organic ligands for preparing MOFs. The synthesized catalysts were characterized and their performances in glucose dehydration to produce 5-hydroxymethylfurfural (5-HMF) have been evaluated. The developed approach in this work has clearly depicted a roadmap for the facile synthesis of MOFs catalysts to facilitate their potential use in acid–base catalysis.
研究领域:
化学工程
·
催化科学
✓ 已验证
产品关联
DOI
高影响因子
RSC Advances
·
2015
·Vol. 6
·期 3
·2241-2251
·
IF 3.84
Xiaohua Sun,Weilong Luo,Linlin Chen,Linjie Zheng,Chao Bao,Panpan Sun,Niu Huang,Yihua Sun,Liang Fang,Lei Wang
Porous Al doped ZnO (AZO) nanosheets have been prepared as an efficient multifunctional water treatment material. Their fundamental properties were characterized by various spectroscopic testing methods. The AZO nanosheets displayed very rapid adsorption rate and high adsorption capacity for methyl orange (MO) dye. The kinetics and equilibrium of adsorption process were found to follow the pseudo-second-order kinetic and Langmuir isotherm models, respectively. Furthermore, the AZO nanosheets exhibited superior photodecolorizative activity compared with the commercial P25 TiO2 nanoparticles. It was found that Al doping increased the zeta potential of AZO nanosheets and then significantly enhanced the adsorption capacity for MO dye and, at the same time, retarded the recombination of photoexcited electron–hole pairs, and prolonged the lifetime of the photo-generated carriers, and then improved the semiconductor photocatalytic activity. In addition, the visible-light-driven dye photosensitized degradation was also an important reason for enhanced photodecolorizative activity. Therefore, AZO nanosheets are a potential multifunctional water treatment material combining highly efficient adsorption and photocatalytic degradation.
研究领域:
材料科学
·
环境化学
·
纳米技术
·
光催化
·
水处理
✓ 已验证
DOI
高影响因子
CHINESE JOURNAL OF CHEMICAL ENGINEERING
·
2017
·Vol. 25
·期 10
·1435-1441
·
IF 1.174
Zhirong Chen,Weitao Yang,Hong Yin,Shenfeng Yuan
The uncatalyzed reaction of p -tolyl isocyanate ( p -TI) with water in N , N -dimethylformamide (DMF) was investigated by high performance liquid chromatography (HPLC). The reactions were carried out at different temperatures from 293 K to 323 K, using various molar ratios of water to p -TI. DMF, as a special amide , was proved to be an efficient catalyst for water–isocyanate reaction. Under the reaction conditions in this study, substituted urea was the only final product observed. An appreciable amount of intermediate p -toluidine was detected. Concentrations of the isocyanate group as well as the amine and urea were determined as a function of time. New kinetic equations were deduced for each of the substance on the basis of a multistep mechanism, instead of a simple second order reaction as usual. Kinetic constants were calculated using the software MATLAB . Furthermore, the effects of temperature and concentrations of reactants on the reaction rate and amine content were discussed. The activation energy of each step was also determined.
研究领域:
物理化学
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有机化学
·
反应动力学
·
高分子化学
·
催化化学
·
分析化学
✓ 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
CHEMICAL ENGINEERING JOURNAL
·
2015
·
IF 4.321
Yajie Qian,Xuefei Zhou,Yalei Zhang,Peizhe Sun,Weixian Zhang,Jiabin Chen,Xin Guo,Xiao Zhang
Calcium peroxide (CP) combined persulfate (PS) oxidation is an emerging in situ chemical oxidation (ISCO) technology for ground water remediation. Many field cases also confirm its effectiveness in ground water remediation while few research articles document it. This study investigated the performance of α-methylnaphthalene (MN) degradation by PS/CP to further understand this dual oxidant application in ISCO. Results showed that MN could be completely oxidized in 72 h with 1 g L −1 PS and 1 g L −1 CP. The degradation rates of MN increased with the increase of PS and CP concentration. MN degradation was significantly enhanced with the solution pH decrease, because CP was easier to dissolve and generated more radicals in acidic condition. Solutes in ground water including chloride ions, alkalinity and natural organic matters presented inhibitory effect on MN degradation in this dual oxidant system. Plausible mechanisms of the sulfate and hydroxyl radicals in the system were proposed based on the results of radical scavenging experiments and electron spin resonance (ESR) tests. It appeared that surface OH of CP was also responsible for the MN removal. The major oxidation products in this study were 1-naphthaldehdye, naphthalene-1-ylmethanol and 4-hydroxy-4-methylnaphthalen-1(4H)-one. To better understand PS/CP in ISCO, the degradation of MN was tested in ground water matrix, which showed satisfactory efficiency. The results of this study provided some detail information of PS/CP dual oxidant in degradation organic contaminants, which might provide some references for the application of this technology in ISCO.
研究领域:
环境工程
·
环境化学
·
污染控制
·
土壤与地下水修复
·
高级氧化技术
✓ 已验证
DOI
高影响因子
INDUSTRIAL CROPS AND PRODUCTS
·
2018
·
IF 3.849
Shujie Ma,Leilei Fu,Siqi He,Xiaopeng Lu,Yuanyong Wu,Zhiqing Ma,Xing Zhang
The evaluation of herbicidal activity and the isolation of plant allelopathic substances can lead to the discovery of new herbicide. This study has confirmed that the ethanol extract of S. mukorossi leaves was inhibitory to growth of Avena fatua L. and Amaranthus retroflexus L. both in petri dish experiment and pot culture assay, with the fresh weight inhibition varied between 47.60% and 62.05% at a concentration of 40 g/L of the leaf extract, being comparable to that of a commercialized natural product herbicide pelargonic acid at a concentration of 4 g/L. Five herbicidal compounds, oleanolic acid (1) , lupeol (2) , d-pinitol (3) , hexadecanoic acid (4) and octadecanoic acid (5) were isolated from the most active fraction, petroleum ether extract. D-pinitol (3) showed the highest growth inhibitory activity against both the shoot and root of A. fatua , with the half maximal inhibitory concentration (IC 50 ) values of 53.61 and 56.43 μg/mL, respectively. Furthermore, oleanolic acid (1) and d-pinitol (3) also inhibited the growth of A. retroflexus with the IC 50 value of 56.05 and 61.89 μg/mL against shoot growth, and 58.07 and 66.70 μg/mL against root growth, respectively. Thus, oleanolic acid (1) and d-pinitol (3) are the main phytotoxin constituents of S. mukorossi , and these compounds have the potential for further development as a botanical herbicide.
研究领域:
植物生理学
·
化感作用
·
天然产物化学
·
杂草科学
·
农药学
✓ 已验证
DOI
高影响因子
RSC Advances
·
2016
·Vol. 6
·期 72
·67827-67832
·
IF 3.289
W. X. Chen,J. S. Yu,W. Hu,Z. L. Chen,H. Memon,G. L. Chen
A core/shell heterostructured nanonanocomposite catalyst based on NiO nanoflakes and titanate nanowires (TNWs) was fabricated. The experimental results showed that the precursor concentration and the reaction time for NiO deposition played significant roles in determining the resulting heterostructure, and an optimal precursor's concentration would result in a well-defined core/shell heterostructure. The XRD analysis demonstrated the existence of the (1 1 1), (2 0 0) and (3 1 1) lattice planes of the NiO nanoflakes. Nearly 100% of the MB pollutant (10 mg L−1) was photodegradaded by the TNWs/NiO catalyst within 50 minutes under UV light irradiation.
研究领域:
材料化学
·
环境催化
·
纳米材料科学
·
光催化降解
·
功能材料
✓ 已验证
DOI
高影响因子
MICROPOROUS AND MESOPOROUS MATERIALS
·
2021
·
IF 5.455
Zhe Zhang,Lei Xu,Yani Liu,Runtian Feng,Tong Zou,Yuanshuo Zhang,Yuru Kang,Pengxin Zhou
In order to improve the efficiency of the removal of methylene blue from wastewater, we synthesized activated carbon by thermally activating phosphoric acid-treated mangosteen peels. This activated carbon possessed a great specific surface area (1832 m 2 /g) and exhibited excellent adsorption capacity (871.49 mg/g) for methylene blue. In this study, we varied the impregnation ratios, activation temperatures, and activation time to determine the best conditions for preparing the mangosteen peel activated carbon (MPAC). The optimal conditions included a 1:3 impregnation ratio with activation for 60 min at 450 °C. We characterized the MPAC using a scanning electron microscope, powder X-ray diffraction, thermogravimetric analysis , differential scanning calorimetry , and Fourier transform infrared spectroscopy together with the Brunauer–Emmett–Teller approach. The adsorption experiment results conformed to the pseudo-second-order kinetic model and the Langmuir isotherm model. This proved that physical adsorption dominates in this adsorption process . The synthesized MPAC-5 showed great adsorption performance for a variety of dye wastewater. After three times of recycling, the removal rate of methylene blue is still above 40%. Compared with other biowastes, mangosteen peel has the potential to be synthesized into activated carbon with a high adsorption capacity for dyes.
研究领域:
环境科学
·
材料科学
·
化学工程
·
污染控制
·
吸附技术
·
废物资源化
✓ 已验证
DOI
高影响因子
CARBOHYDRATE POLYMERS
·
2015
·
IF 4.074
Chao Zhong,Chunming Wang,Fengxue Wang,Honghua Jia,Ping Wei,Yin Zhao
Cellulose isolation, a promising way for lignocellulosic biomass utilization, is always restricted by the poor solubility of cellulose. In this paper, tetra-n-methylammonium hydroxide (TMAH) was confirmed to be capable of readily dissolving/regenerating cellulose without chemical modification at room temperature. Meanwhile, cellulose isolation from lignocellulosic biomass by initially dissolving the biomass in TMAH followed by cellulose precipitation was proposed, and the isolated substance with average cellulose purity of 92.1 ± 0.3% could be obtained throughout this process under the optimum conditions: temperature 52 °C, time 60 min, and loading ratio of TMAH/biomass ( w / w ) 7.2:1. Besides, high efficiency cellulose isolation (i.e. >70% cellulose purity) could be continuously remained during 4-round cycles by using the recycled TMAH solvent without distinct activity loss.
研究领域:
生物质化学
·
绿色溶剂
·
天然高分子
·
可持续材料
·
生物精炼
✓ 已验证
DOI
高影响因子
危险品化学品经营许可证（带存储）