CHEMICAL ENGINEERING JOURNAL
·
2016
·
IF 5.31
Ting Wang,Pan Zhao,Nan Lu,Hongche Chen,Conglu Zhang,Xiaohong Hou
Attractive magnetic metal-organic framework (MOF) material Fe 3 O 4 /MIL-101(Cr) (Matérial Institute Lavoisier, MIL) was synthesized by a simple reduction–precipitation method, and applied as an effective sorbent to the removal of two acid dyes, acid red 1 (AR1) and orange G (OG), in water. The novel synthetic method avoided the oxidation of Fe 2+ and made the Fe 3 O 4 /MIL-101(Cr) composite have the advantages of strong magnetism, large surface areas and excellent dispersion effect. Parameters that influenced the adsorption process, such as solution pH, adsorbent dosage, ionic strength, and so on, were investigated. Under the optimum conditions, adsorption kinetics and isotherms were determined from the obtained experimental data. The adsorption kinetics suggested the adsorption process of Fe 3 O 4 /MIL-101(Cr) toward AR1 and OG met the pseudo-second-order kinetic model. The adsorption isotherms were fitted by Langmuir, Freundlich and Dubinin–Radushkevich (D–R) isotherm models. Compared with the Freundlich and D–R models, the Langmuir isotherm model was found to be suitable to describe the equilibrium data, suggesting that the uptake of AR1 and OG by the Fe 3 O 4 /MIL-101(Cr) would be through monolayer adsorption. The thermodynamic results demonstrated that the adsorption was a spontaneous, exothermic and entropy decreased process. In addition, the Zeta potential data with pH value of AR1 and OG indicated that the electrostatic interactions between the dyes and the adsorbent might be critical to the adsorption mechanism. The used Fe 3 O 4 /MIL-101(Cr) could be regenerated by washing with NaOH solution and reused at least six times. The maximum adsorption capacities of the magnetic composite toward AR1 and OG were up to 142.9 mg g −1 and 200.0 mg g −1 , respectively. These results demonstrated that the novel composite would be an effective and easily re-usable adsorbent for AR1 and OG.
✓ 已验证
DOI
高影响因子
PLoS One
·
2016
·Vol. 11
·期 2
·e0149032
·
IF 3.057
Zhao Gao,Yu Han,Yunhui Hu,Xiaoyan Wu,Yongbin Wang,Xiaoqun Zhang,Jinjuan Fu,Xue Zou,Jun Zhang,Xiongwen Chen,Pedro A. Jose,Xi Lu,Chunyu Zeng
Both oxidative stress and inflammation are involved in the pathogenesis of contrast-induced nephropathy (CIN). Epigallocatechin-3-gallate (EGCG), a purified catechin from green tea, has antioxidant and anti-inflammatory effects. However, it is unknown whether or not EGCG is effective in treating CIN. Our present study found that intravenous administration of EGCG, either before or just after the establishment of CIN, had a protective effect, determined by normalization of serum creatinine and blood urea nitrogen levels, improvement in renal histopathological scoring and alleviation of apoptosis, accompanied by decreased oxidative stress and inflammation. Because EGCG is a potent inducer of the antioxidant heme oxygenase-1 (HO-1), we studied HO-1 signaling in CIN. HO-1 levels were increased in CIN; treatment with EGCG further increased HO-1 levels, accompanied by an increase in Nrf2, a regulator of antioxidant proteins. Interestingly, blockade of HO-1 with protoporphyrin IX zinc(II) (ZnPP) prevented the protective effect of EGCG on CIN. ZnPP also blocked the ability of EGCG to increase the activity of an antioxidant (superoxide dismutase), and decrease markers of oxidative stress (myeloperoxidase and malondialdehyde) and inflammation (myeloperoxidase and IL-1β), indicating that HO-1 is the upstream molecule that regulates the EGCG-mediated protection. To determine further the role of HO-1 on the EGCG-mediated inhibition of inflammation, we studied the effect of EGCG on the NLRP3 inflammasome, an upstream signaling of IL-1β. EGCG down-regulated NLRP3 expression, which was blocked by ZnPP, indicating that HO-1 links EGCG with NLRP3. Therefore, EGCG, via up-regulation of HO-1, protects against CIN by amelioration of oxidative stress and inflammation.
✓ 已验证
产品关联
DOI
PubMed
高影响因子
LANGMUIR
·
2016
·
IF 3.993
Ping Zhang,Ling Li,Yun Zhao,Zeyun Tian,Yumei Qin,Jun Lu
The fluorescent dye 8-anilino-1-naphthalenesulfonate (ANS) is a widely used fluorescent probe molecule for biochemistry analysis. This paper reported the fabrication of ANS/layered double hydroxide nanosheets (ANS/LDH)n ultrathin films (UTFs) via the layer-by-layer small anion assembly technique based on electrostatic interaction and two possible weak interactions: hydrogen-bond and induced electrostatic interactions between ANS and positive-charged LDH nanosheets. The obtained UTFs show a long-range-ordered periodic layered stacking structure and weak fluorescence in dry air or water, but it split into three narrow strong peaks in a weak polarity environment induced by the two-dimensional (2D) confinement effect of the LDH laminate; the fluorescence intensity increases with decreasing the solvent polarity, concomitant with the blue shift of the emission peaks, which show good sensoring reversibility. Meanwhile, the UTFs exhibit selective fluorescence enhancement to the bovine serum albumin (BSA)-like protein biomolecules, and the rate of fluorescence enhancement with the protein concentration is significantly different with the different protein aggregate states. The (ANS/LDH)n UTF has the potential to be a novel type of biological flourescence sensor material.
✓ 已验证
产品关联
DOI
PubMed
高影响因子
ENERGY & FUELS
·
2017
·
IF 3.091
Cheng Sun,Shujing Wen,Jingkai Zhao,Chongjian Zhao,Wei Li,Sujing Li,Dongxiao Zhang
In this work, the blends of 1-hydroxyethyl-3-methylimidazolium glycine ([C2OHmim][Gly]) synthesized by our laboratory and N-methyldiethanolamine (MDEA) in aqueous solution were prepared for CO2 capture, and the maximum absorption performance of the blends was obtained at the mole ratio of 8:2 of MDEA/[C2OHmim][Gly] with a total concentration of 1.0 mol L–1. CO2 loading of the blended absorbent was less adversely influenced by the temperature and O2 concentration than that of MDEA aqueous, and it had a good performance in regeneration ability. The reaction mechanism of the CO2 absorption in MDEA/[C2OHmim][Gly] was investigated by 13C nuclear magnetic resonance. CO2 first reacted with [C2OHmim][Gly] to form carbamate, and then carbamate promoted the reaction between CO2 and MDEA, which could be described as a shuttle mechanism. The kinetics of CO2 absorption was investigated in a double stirred-cell absorber at different temperatures, and some important kinetic parameters were obtained, such as the reaction rate constant (k2) and the overall rate constant (kov). Experimental results indicated that the addition of [C2OHmim][Gly] enhanced CO2 absorption of MDEA under low CO2 partial pressure, which could improve the application of MDEA in industry.
✓ 已验证
产品关联
DOI
高影响因子
POLYMER
·
2017
·
IF 3.684
Hongyao Ding,Xin Ning Zhang,Si Yu Zheng,Yihu Song,Zi Liang Wu,Qiang Zheng
As a promising structural material, various tough hydrogels have been developed in recent years by incorporating different kinds of noncovalent bonds as the energy-dissipating segments. Among these systems, it is challenging to use hydrogen bonds due to their instability in aqueous environment. Here we report a tough hydrogel of poly(1-vinylimidazole- co -acrylic acid) (P(VI- co -AAc)) reinforced by the robust hydrogen bonds between imidazole and carboxylic acid groups. The hydrogels with different composition possess excellent mechanical performances, with tensile breaking stress, breaking strain, Young's modulus , and tearing fracture energy being 0.3–1.8 MPa, 920–1400%, 0.1–0.7 MPa, and 0.7–5.6 kJ/m 2 , respectively, which are well maintained over a wide pH range (3 ≤ pH ≤ 10). The high stability of hydrogen bonds should be rooted in the strong proton donor-acceptor pair. However, when pH ≤ 2 or pH ≥ 11, the gels become highly swelled due to the dissociation of imidazole and carboxylic acid groups, respectively, accompanying with dramatic decrease in mechanical properties . The tough hydrogels also show temperature- and deformation rate-dependent mechanical properties , as well as shape memory and self-recovery abilities, due to the dynamic nature of noncovalent bonds. Such hydrogels with remarkable mechanical properties and dual pH-responsiveness should find applications in load-bearing soft actuators, flexible electronics, etc.
✓ 已验证
产品关联
DOI
高影响因子
PROCESS BIOCHEMISTRY
·
2017
·
IF 2.497
Shu-Ping Zou,Ji-Wei Huang,Ya-Ping Xue,Yu-Guo Zheng
1-Cyanocyclohexaneacetic acid (1-CHAA) is an important intermediate in the preparation of gabapentin. Regioselective biotransformation of 1-cyanocyclohexaneacetonitile (1-CHAN) into 1-CHAA, mediated by the immobilization of recombinant microbial nitrilase, is a novel and promising strategy for its production. In this study, a recombinant E. coli expressing Acidovorax facilis nitrilase was flocculated with polyethylenemine, followed by cross-linking with glutaraldehyde to obtain cross-linked cell aggregates (CLCAs). Under the optimum preparation conditions, the activity recovery of CLCAs reached 68%. Characterization of the CLCAs showed that the optimum pH was not affected by cross-linking, but cross-linking resulted in slightly different optimum temperature. The half-life of CLCAs at 45 °C was 266.5 h, which is 11.6-times higher than that of the free cells. Preparative-scale biotransformation of 1-CHAN to 1-CHAA at high substrate loading (up to 1.0 M) was performed using CLCAs as the biocatalyst in a 2L stirred reactor, resulting in an conversion of 91%, with a productivity of 244.5 g L −1 d −1 . The CLCAs also exhibited a high operational stability and even after 30 cycles of reaction, it retained >80% of the initial conversion.
✓ 已验证
产品关联
DOI
高影响因子
OPTIK
·
2013
·
IF 0.524
Zhijuan Cao,Fengxian Qiu,Qing Wang,Guorong Cao,Lin Zhuang,Qiang Shen,Xiaolong Xu,Jie Wang,Qian Chen,Dongya Yang
The azo benzothiazole polyurethane–urea (ABPUU) was synthesized from chromophore molecule 4-[(6-nitrobenzothiazole-2-yl)diazenyl]phenyl-1,3-diamine NBDPD, polyether polyol (NJ-210) and isophorone diisocyanate (IPDI). The structure, thermal property , mechanical property and physical property were characterized and investigated. The refractive index ( n ) and thermo-optic coefficient (d n /d T ) of ABPUU was determined at different temperature and wavelength (532 nm, 650 nm and 850 nm) using attenuated total reflection (ATR) technique. Using the CCD digital imaging devices, transmission loss of ABPUU was measured. A 1 × 2 Y-branched and 2 × 2 Mach–Zehnder interferometer (MZI) switch with two rib waveguides , dual driving electrodes and two critical 3-dB couplers polymeric thermo-optic switches based on thermo-optic effect of prepared ABPUU were designed and simulation. The power consumption of the Y-branched switch is less than 0.84 mW. The Y-branched and MZI switching rising and falling times obtained are 0.8 ms and 0.2 ms, respectively.
✓ 已验证
产品关联
DOI
高影响因子
MATERIALS RESEARCH BULLETIN
·
2012
·
IF 2.105
Hongwei Wei,Hechun Jiang,Zhen Zheng,Quanqin Zhao,Qingyin Wu,Jinhua Zhan
A series of one-dimensional Cd x Zn (1− x ) S semiconductor alloys were prepared via a hydrothermal method with the assistance of ethylenediamine at 180 °C for 12 h. The products were characterized by X-ray diffraction, scanning electron microscopy, transmission electron microscopy, nitrogen adsorption/desorption and Fourier transform infrared techniques. With the value of x increased, the band gap of Cd x Zn (1− x ) S semiconductor alloys gradually decreased indicating that catalysts were exchanged to visible-light response. Photocatalytic reduction results showed that Cd 0.73 Zn 0.27 S exhibited the highest photocatalytic activity toward photo production of aniline via nitrobenzene reduction under visible irradiation respectively. The reaction mechanism was also discussed.
✓ 已验证
产品关联
DOI
高影响因子
ANALYTICAL CHEMISTRY
·
2015
·
IF 5.636
Jialiang Pan,Shu Jia,Gongke Li,Yuling Hu
Microporous organic polymers (MOPs) are an emerging class of functional porous materials for diverse potential applications. Typically, tailored microporous structures of MOPs are generated by linkages of organic polymerizable monomer building blocks, providing high permanent porosity and excellent stability. Herein, we reported the first example of the application of organic building block based MOPs (OBB-MOPs) as efficient enrichment media for sample preparation. A novel multilayer interbridging strategy was proposed to fabricate OBB-MOP coatings, and hereby SNW-1 (a kind of OBB-MOPs) was coated on silica substrate with well-controlled thickness. Strong covalent bonds throughout the network and interlayer bridging improved the durability of the coating significantly. Outstanding chemical stability was observed in diverse solvents as well as solutions with a wide range of pH or high ionic strength and even under extremely harsh conditions like boiling water. The SNW-1 coating possessed a microporous network structure constructed of conjugated and nitrogen-rich building blocks. Thus, the coating exhibited a superior enrichment performance of polycyclic aromatic hydrocarbons and volatile fatty acids (VFAs) over commercial coatings based on interactions including π–π affinity and acid–base interaction. For further application, this coating was combined with gas chromatography/mass spectrometry for the noninvasive analysis of VFAs from tea leaf and tobacco shred samples. The low detection limits of 0.014–0.026 μg/L were achieved with the relative standard deviations (RSDs) between 4.3 and 9.0%. Consequently, trace original VFAs from the samples were detected. Good recoveries were obtained in the range of 90–129% and 77–118% with the corresponding RSDs (n = 3) of 2.6–9.3% and 1.9–10%, respectively.
✓ 已验证
产品关联
DOI
PubMed
高影响因子
CHEMICAL ENGINEERING JOURNAL
·
2013
·
IF 3.473
Yingying Luo,Ziyang Lu,Yinhua Jiang,Dandan Wang,Lili Yang,Pengwei Huo,Zulin Da,Xuliang Bai,Xulan Xie,Pengyi Yang
The magnetic and dual conductive imprinted photocatalysts (MCIPs) were synthesized through the suspension polymerization method. TiO 2 /Fe 3 O 4 /MWCNTs, 1-methylimidazole-2-thiol and pyrrole were used as supports, template molecule and functional monomer, respectively. The MCIPs were further characterized by X-ray diffraction (XRD), Fourier transform infrared spectra (FT-IR), scanning electron microscopy (SEM), transmission electron microscope (TEM), UV–visible diffuse reflectance spectra (UV–vis DRS), thermogravimetric analysis (TGA) and vibrating sample magnetometer (VSM). The result revealed that polypyrrole (PPy) was formed and well embedded in the surface imprinted layer of TiO 2 /Fe 3 O 4 /MWCNTs. Owing to PPy and MWCNTs, the MCIPs was equipped with dual conductivity which was particularly useful for photodegradation of 1-methylimidazole-2-thiol in aqueous solution under ultraviolet irradiation. Through a series investigation of factors, it was obvious that when the polymerization time was 24 h and the adding dose of pyrrole was 8 mmol, the resulting MCIPs obtained the highest photocatalytic ability. In addition, the photodegradation process obeyed the pseudo-first-order kinetic reaction and exhibited an excellent selective degradation ability of 1-methylimidazole-2-thiol. The degradation intermediate products and mechanism of 1-methylimidazole-2-thiol were further discussed.
✓ 已验证
产品关联
DOI
高影响因子
POSTHARVEST BIOLOGY AND TECHNOLOGY
·
2013
·
IF 2.454
Jianwen Bu,Zhendan Ni,Guzhanuer Aisikaer,Zhenhui Jiang,Zia Ullah Khan,Wangshu Mou,Tiejin Ying
Mature green cherry tomato fruit were harvested and treated with ultraviolet-C (UV-C) irradiation at a predetermined dose of 4.2 kJ m −2 , and stored at 18 °C for 35 days. The effects of UV-C treatment on color change, pigment contents, and the expression of major genes involved in carotenoid metabolism, including Psy 1, Pds , Lcy - β , and Lcy - ɛ , encoding phytoene synthase, phytoene desaturase, lycopene β-cyclase and lycopene ɛ-cyclase, respectively, were examined. The UV-C treated fruit developed a pink red color in contrast to the normal orange red color of control fruit. Lycopene accumulation during ripening in UV-C treated fruit was significantly inhibited but its final content was not affected. However, both accumulation and final content of β-carotene were significantly suppressed in UV-C treated fruit. The lower content of β-carotene, leading to a higher lycopene to β-carotene ratio, is probably responsible for the altered color phenotype in UV-C treated fruit. Psy 1, a major gene involved in lycopene synthesis was inhibited by UV-C irradiation. Significantly suppressed expression of Lcy-β gene was also observed in UV-C treated fruit. Thus it is possible that the lower transformation from lycopene to carotenes contributed to the relatively stable content of lycopene.
✓ 已验证
产品关联
DOI
高影响因子
INTERNATIONAL JOURNAL OF HYDROGEN ENERGY
·
2014
·
IF 2.93
Weirong Zhao,Zhuyu Ai,Xi Zhu,Meng Zhang,Qiaomeng Shi,Jiusong Dai
(AgNbO 3 ) 1− x (SrTiO 3 ) x samples were successfully employed as photocatalysts for photocatalytic hydrogen evolution under visible light. The samples were characterized by a series of techniques, including X-ray diffractometry, scanning electron microscopy, UV–Vis spectrophotometry , and electrochemistry technology. The band gaps of (AgNbO 3 ) 1− x (SrTiO 3 ) x solid solutions can be tuned continuously from 3.21 to 2.65 eV and the flat-band potentials ( V fb ) can be shifted positively from −0.79 to −0.31 V vs. SHE when x decreased from 1 to 0. Band positions of (AgNbO 3 ) 1− x (SrTiO 3 ) x samples were further testified by density functional theory, suggesting that the band gap narrowing of the solid solutions derived from the hybridization of (Ti 3d and Nb 4d) and (O 2p and Ag 4d) orbital. The photocatalytic activities of samples for H 2 evolution with Pt cocatalyst were evaluated in aqueous methanol solution under visible light irradiation . The highest photocatalytic activity was obtained at (AgNbO 3 ) 0.25 (SrTiO 3 ) 0.75 . Photocatalytic activity in hydrogen evolution of these solid solutions proved to be closely dependent on band structures .
✓ 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）