KOREAN JOURNAL OF CHEMICAL ENGINEERING
·
2012
·Vol. 29
·期 10
·1388-1392
·
IF 0.991
He Minqiang,Pan Aixia,Xie Jimin,Li Huamin,Yuan Xinhua,Cheng Xiaonong,Chen Min
A novel one-pot catalytic synthesis of 1-benzoylpyrene through acylation of pyrene with benzoic anhydride catalyzed by several heteropoly acids (HPAs) was investigated. Pure 1-benzoylpyrene was obtained and its structure was identified by GC/MS, FT-IR and 1 H NMR spectra. Silica-supported phosphotungstic heteropoly acid (PW/SiO 2 ) was found to be the most active catalyst in the acylation. The yield and the selectivity of 1-benzoylpyrene were up to 62.5% and 100%, respectively. The effects of experimental parameters on the catalytic acylation reaction, and the possibility of reusability of PW/SiO 2 catalyst were studied. PW/SiO 2 catalyst is easily separable from the reaction mixture and reusable without loss of its activity.
研究领域:
有机化学
·
催化材料科学
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DOI
高影响因子
TRIBOLOGY LETTERS
·
2017
·Vol. 66
·期 1
·1-18
·
IF 1.891
Xin Yuanshi,Xu Fanglin,Wang Mingming,Li Tongsheng
Modified carbon nanotube/nano-MoS 2 (CMS) hybrid as a self-lubricating and anti-wear nanofiller was prepared through chemical compounding and then incorporated into polyimide (PI) matrix to yield CMS/PI composite by in situ polymerization. For comparison, carbon nanotube (CNT), nano-MoS 2 as well as the mixture of them (CNT-MoS 2 ) were also incorporated into PI matrix separately to evaluate the superior performance of CMS hybrid. Morphology, mechanical capacity and tribological behavior of the as-prepared nanocomposites were investigated, and the discrepancies on the above-mentioned properties caused by the different structures between CMS hybrid and CNT-MoS 2 mixture were discussed in detail. With only 0.5 wt% addition of CMS, the friction coefficient and wear rate of CMS/PI composite decreased by 31 and 84%, respectively, compared to virgin PI. The results showed that the combinational structure of CMS hybrid, as CNT-coated few-layer MoS 2 nanosheet, which took the advantage of both CNT and nano-MoS 2 , contributed to the synergistic effect on the tribological properties.
研究领域:
材料科学
·
摩擦学
✓ 已验证
DOI
高影响因子
ENVIRONMENTAL SCIENCE AND POLLUTION RESEARCH
·
2018
·Vol. 25
·期 31
·30938-30948
·
IF 2.8
Guo Shuangzhen,Dan Zhigang,Duan Ning,Chen Guanyi,Gao Wubin,Zhao Weijie
A novel magnetic silica gel adsorbent (Fe 3 O 4 -Si-COOH) was successfully prepared by introducing carboxyl group in situ to improve the performance for Pb(II), Zn(II), and Cd(II) adsorption. Infrared spectroscopy (IR), scanning electron microscope (SEM), transmission electron microscope (TEM), thermo-gravimetric analyzer (TGA), the Brunauer-Emmett-Teller (BET) surface area, X-ray diffraction (XRD), and vibrating sample magnetometer (VSM) characterizations suggested that Fe 3 O 4 -Si-COOH has been successfully prepared. The adsorption performance was evaluated by batch experiments with different initial concentrations, ionic strength, contact time, and pH. The adsorption kinetics data followed pseudo-second-order model and exhibited a three-stage intraparticle diffusion mode. Isothermal adsorption equilibrium data were best fitted by the Freundlich model and the adsorption capacity were 155, 110, and 93 mg/g (initial concentration 210 mg/L) for Pb(II), Zn(II), and Cd(II), respectively. The result of X-ray photoelectron spectroscopy (XPS) survey spectrum suggested that the main adsorption mechanism is that the H + of carboxyl groups exchanged with heavy metal ions in the adsorption processes. In addition, the adsorbed Fe 3 O 4 -Si-COOH could be regenerated and the adsorption capacity of reused Fe 3 O 4 -Si-COOH could maintain 80.3% after five cycles. Hence, the Fe 3 O 4 -Si-COOH could be a kind of potential material for removing Pb(II), Zn(II), and Cd(II) from wastewater.
Graphical abstract
研究领域:
环境科学
·
材料科学
✓ 已验证
DOI
高影响因子
Science China-Materials
·
2022
·Vol. 66
·期 4
·1460-1470
·
IF 8.64
Cheng Yufei,Sun Qian,Li Qiujie,Zhang Wenwan,Liu Enzhou,Fan Jun,Xie Haijiao,Miao Hui,Hu Xiaoyun
Antimony selenide (Sb 2 Se 3 ) is a narrow-band-gap semiconductor that has been increasingly used as an excellent light-harvesting material in photoelectrocatalysis. The unique connections of the one-dimensional (Sb 4 Se 6 ) n ribbon structural units determine the high anisotropy of their carrier transport. In this study, a reduced graphene oxide (rGO)-modified quasi-one-dimensional Sb 2 Se 3 @In 2 S 3 light-trapping heterostructure was successfully constructed by vapor transport deposition followed by an in situ hydrothermal method. The results showed that the thickness of the in situ grown non-layered In 2 S 3 nanosheets was significantly reduced from 30 to 10 nm under the space-confinement effect of rGO, facilitating the construction of light-trapping nanostructures and increasing the electrochemically active surface area of the photoelectrode. The quasi-one-dimensional Sb 2 Se 3 @In 2 S 3 -rGO nanorod photoelectrode achieved a higher photocurrent density (1.169 mA cm −2 ), which was 2 and 16 times higher than that of Sb 2 Se 3 @In 2 S 3 and pristine Sb 2 Se 3 , respectively. The ultrathin In 2 S 3 nanosheets were co-modified with rGO nanosheets to fabricate a brush-like composite photoelectrode that exhibited favourable stability with an average hydrogen production rate of 16.59 µmol cm −2 h −1 under neutral conditions. The experimental results and theoretical calculations both showed that the significant improvement in photoelectrochemical performance can be perfectly explained by the type-II heterojunction mechanism. This study provides a new exploration to design rGO-modified composite photoelectrodes for photoelectrochemical applications.
研究领域:
材料科学
·
光电化学
✓ 已验证
DOI
高影响因子
POLYMER BULLETIN
·
2017
·Vol. 74
·期 9
·3907-3922
·
IF 1.43
Wei Yanyan,Du Xiucai,Ma Xiaoyue,Zhao Kaifeng,Zhang Shiyu,Bai Yapeng
Highly cross-linked polyurethanes based on Diels–Alder (DA) reaction have high hardness but poor toughness. A modified polyurethane with three-furyl diol (TF) was synthesized innovatively to improve its mechanical properties. Three-furyl diol (TF) and hydroxyl terminated polyurethane IDI-TF were synthesized first. Then the reaction of IDI-TF with xylene bismaleimide (BMI) generates cross-linked polyurethane ITB-PU (its soft segment content is 11.5%). Finally, the properties of the polyurethane ITB-PU were characterized by a series of methods. It can be observed that the DA reaction occurred at 50.33 °C, the r-DA reaction at 69.55 °C. When heated at 80 °C for 6 h, the self-healing efficiency of the ITB-PU was 43.91% known from the tensile test, and cracks on it virtually disappeared seen from polarizing microscope (POM). When heat was preserved for 12 h, the self-healing efficiency can reach 80.02%.
研究领域:
材料科学
·
化学工程
✓ 已验证
DOI
高影响因子
JOURNAL OF SOLUTION CHEMISTRY
·
2013
·Vol. 42
·期 9
·1782-1793
·
IF 1.128
Lu Jia,Li Shu’ni,Zhai Quanguo,Jiang Yucheng,Hu Mancheng
The mean activity coefficients for CsCl in N -methylformamide or urea ( w ) + H 2 O (1 − w ) systems were determined in this work by potentiometry, using ion-selective electrodes at 298.15 K. The value of mass fraction w was varied between 0.00 and 0.40 in five unit-steps and the molality of CsCl was between 0.0020 and 1.4009 mol·kg −1 . The experimental data have been correlated with the Pitzer, modified Pitzer and the extended Debye–Hückel equations. The resulting values of the mean activity coefficients, the osmotic coefficients and the standard Gibbs energy of transfer, together with the Pitzer ion-interaction parameters ( β
(0) , β
(1) and C
φ ), extended Debye–Hückel parameters ( a , c and d ), and modified Pitzer parameters ( b , B
MX , C
MX ) are reported for the investigated systems.
研究领域:
化学
·
物理化学
✓ 已验证
DOI
高影响因子
International Journal of Environmental Science and Technology
·
2022
·Vol. 20
·期 6
·6777-6790
·
IF 3.519
Liu H.,Wu S. F.
In situ pore forming achieved by vapor releasing of chemical looping reaction for dynamic compensation of lost pore volume was proposed to improve the durability of the nano-CaO-based adsorbent in calcium looping process. The effect of contents (12–34 wt.%) and kinds of the pore forming agents (MnO 2 , Fe 2 O 3 , Co 2 O 3 , NiO and CuO) on the dynamic pore compensation effect and sorption performance including sorption capacity and durability of the adsorbent was investigated. The results showed that high pore forming capacity could be achieved by high doping content and oxygen mass fraction of agent. Good anti-sintering ability of agent could leads to a prominent pore forming stability. The final dynamic pore compensation effect was controlled by both pore forming capacity and stability. Compared with the nano-CaO/Al 2 O 3 adsorbent, the best dynamic pore compensation effect for the nano-CaO-NiO/Al 2 O 3 adsorbent was achieved with doping NiO content of 21 wt.%, which could increase pore volume by 67.3% after 3 CaL cycles. The total average deactivation rate of the nano-CaO-NiO/Al 2 O 3 adsorbent was reduced by 48%, which meant that in situ dynamic pore compensation could significantly improve the cyclic durability of adsorbents. Graphical abstract
研究领域:
材料科学
·
环境工程
✓ 已验证
DOI
高影响因子
Nature Communications
·
2023
·Vol. 14
·期 1
·1-12
·
IF 16.6
Zhang Jiyu,Yan Yongliang,Wang Xin,Cui Yanyan,Zhang Zhengfeng,Wang Sen,Xie Zhengkun,Yan Pengfei,Chen Weihua
Non-aqueous sodium-ion batteries (SiBs) are a viable electrochemical energy storage system for grid storage. However, the practical development of SiBs is hindered mainly by the sluggish kinetics and interfacial instability of positive-electrode active materials, such as polyanion-type iron-based sulfates, at high voltage. Here, to circumvent these issues, we proposed the multiscale interface engineering of Na 2.26 Fe 1.87 (SO 4 ) 3 , where bulk heterostructure and exposed crystal plane were tuned to improve the Na-ion storage performance. Physicochemical characterizations and theoretical calculations suggested that the heterostructure of Na 6 Fe(SO 4 ) 4 phase facilitated ionic kinetics by densifying Na-ion migration channels and lowering energy barriers. The (11-2) plane of Na 2.26 Fe 1.87 (SO 4 ) 3 promoted the adsorption of the electrolyte solution ClO 4 − anions and fluoroethylene carbonate molecules, which formed an inorganic-rich Na-ion conductive interphase at the positive electrode. When tested in combination with a presodiated FeS/carbon-based negative electrode in laboratory- scale single-layer pouch cell configuration, the Na 2.26 Fe 1.87 (SO 4 ) 3 -based positive electrode enables an initial discharge capacity of about 83.9 mAh g −1 , an average cell discharge voltage of 2.35 V and a specific capacity retention of around 97% after 40 cycles at 24 mA g −1 and 25 °C.
研究领域:
电化学
·
材料科学
·
能量存储
✓ 已验证
DOI
高影响因子
RARE METALS
·
2021
·Vol. 40
·期 11
·3195-3204
·
IF 4.003
Lu Zhi-Yu,Yu Hai-Jie,Lu Xiong,Song Meng-Chen,Wu Fu-Ying,Zheng Jia-Guang,Yuan Zhi-Fei,Zhang Liu-Ting
Magnesium hydride (MgH 2 ), which possesses high hydrogen density of 7.6 wt%, abundant resource and non-toxicity, has captured intense attention as one of the potential hydrogen storage materials. However, the practical application of Mg/MgH 2 system is suffering from high thermal stability, sluggish absorption and desorption kinetics. Herein, two-dimensional (2D) vanadium nanosheets (V NS ) were successfully prepared via a facile wet chemical ball milling method and proved to be highly effective on improving the hydrogen storage performance of MgH 2 . For instance, the MgH 2 + 7 wt% V NS composite began to release hydrogen at 187.2 °C, 152 °C lower than that of additive-free MgH 2 . At 300 °C, 6.3 wt% hydrogen was released from the MgH 2 + 7 wt% V NS composite within 10 min. In addition, the fully dehydrogenated sample could absorb hydrogen even at room temperature under hydrogen pressure of 3.2 MPa. X-ray diffractometer (XRD) and transmission electron microscopy (TEM) results confirmed metallic vanadium served as catalytic unit for facilitating the de/rehydrogenation reaction of MgH 2 . This finding presents an example of facile synthesis of two-dimensional (2D) vanadium with excellent catalysis, which may shed light on future design and preparation of highly effective layered catalysts for hydrogen storage and other energy-related areas.
研究领域:
材料科学
·
能源存储
✓ 已验证
DOI
高影响因子
CELLULOSE
·
2017
·Vol. 24
·期 10
·4189-4203
·
IF 3.417
Zhang Xiuqiang,Zhang Jinlong,Dong Lili,Ren Suxia,Wu Qinglin,Lei Tingzhou
We report a series of thermoresponsive cellulose nanocrystals (CNCs) decorated with poly(poly(ethylene glycol) methylacrylate) copolymers (poly(PEGMA)- g -CNCs) synthesized by surface initiated-atom transfer radical polymerization (SI-ATRP). The chemical structures and surface morphologies were subsequently confirmed by FT-IR, XPS, and AFM measurements. With regard to thermally responsive behavior, poly(PEGMA)- g -CNCs show tunable lower critical solution temperature (LCST) values in the range of 34–66 °C by varying the feeding ratios of comonomers. The reversible morphological transformation from individual nano-rod structures to larger globule aggregates was further verified by AFM during the LCST transition. These functionalized CNCs have potential as smart film filters and biosensors.
研究领域:
材料科学
·
高分子化学
✓ 已验证
DOI
高影响因子
JOURNAL OF MATERIALS SCIENCE-MATERIALS IN ELECTRONICS
·
2021
·Vol. 32
·期 17
·21923-21931
·
IF 2.478
Wu Ruifeng,Lin Yuanwei,Liu Yafei,Chang Aimin,Zhao Pengjun,Zhang Bo
In this study, x LaMnO 3 -(1 − x )CaCu 3 Ti 4 O 12 (0 ≤ x ≤ 0.7) composite ceramics have been prepared by the conventional solid-state method. XRD results show that the composite ceramics are mainly composed of LaMnO 3 and CaCu 3 Ti 4 O 12 phases. Electrical property analysis shows that the resistivity ρ 25 gradually decreases from 2.17 × 10 8 to 1.74 × 10 5 Ω·cm with increasing LaMnO 3 content. The relationship between ln ρ and 1000/ T is not linear and changes around 350 °C. In the temperature range of 0–350 °C, the activation energy E a 0–350 °C decreases gradually with the increase of the LaMnO 3 content. In the temperature range of 350–500 °C, the activation energy E a 350–500 °C increases first and then decreases, which is related to the variation of oxygen vacancy. The compounding of LaMnO 3 gives rise to the decrease in B value, thus, providing the potential for the applications of wide temperature range thermistors. After annealing, the coefficient of aging (Δ R / R ) of the composites decreases from 23.73 to 3.01%.
研究领域:
材料科学
·
电气工程
✓ 已验证
DOI
高影响因子
JOURNAL OF MATERIALS SCIENCE
·
2018
·Vol. 53
·期 21
·15196-15203
·
IF 2.993
Song Li,Dong Yan,Shao Qiyue,Jiang Jianqing
Nano-yttrium aluminum garnet (YAG) is a promising material for use in white light-emitting diodes and biological fluorescent probe. However, its existing preparation methods often suffer from low synthesis temperature and particle agglomeration. Therefore, preparing YAG nanoparticles with both high crystallinity and high dispersibility is difficult, which severely limits the applications of nano-YAG phosphor. This work presents a salt microemulsion method that can yield YAG nanoparticles of size 4–6 nm that are dispersed at a high temperature (1000 °C). Transmission electron microscope analysis shows that the precursor particles are dispersed and isolated by nano-sized potassium sulfate particles. Because the melting point of potassium sulfate is high (1067 °C), the precursors and the YAG nanoparticles are always dispersed and isolated by the solid potassium sulfate salt during calcination at high temperatures, resulting in the formation of dispersed YAG nanoparticles with good crystallinity. The reflection spectrum of nano-YAG exhibited a redshift compared to that of bulk YAG. When the Ce content is 0.06, the nano-YAG phosphor exhibited the highest internal photoluminescence quantum yield of 51.2%, and the decrease in the particle size did not increase the quenching concentration. The nano-YAG prepared at a high temperature also exhibited improved optical stability: The luminescence intensity of the nano-YAG decreased by only~ 16% after 48 h of irradiation using blue laser. The obtained 4–6-nm-sized Y 3 Al 5 O 12 :Ce nanophosphors are expected to be ideal materials for novel fluorescent probes and preparation of transparent ceramics.
研究领域:
材料科学
·
光学
✓ 已验证
DOI
高影响因子
危险品化学品经营许可证（带存储）