ENVIRONMENTAL SCIENCE AND POLLUTION RESEARCH
·
2013
·Vol. 21
·期 2
·1401-1410
·
IF 2.618
Wu Xiaoliang,Lu Shuguang,Qiu Zhaofu,Sui Qian,Lin Kuangfei,Du Xiaoming,Luo Qishi
Most studies on the treatment of chlorinated contaminants by Fe(0) focus on aqueous system tests. However, few is known about the effectiveness of these tests for degrading chlorinated contaminants such as 1,1,1-trichloroethane (TCA) in soil. In this work, the reductive degradation performance of 1,1,1-TCA by Fe(0) was thoroughly investigated in a soil slurry system. The effects of various factors including acid-washed iron, the initial 1,1,1-TCA concentration, Fe(0) dosage, slurry pH, and common constituents in groundwater and soil such as Cl − , HCO 3
− , SO 4
2− , and NO 3
− anions and humic acid (HA) were evaluated. The experimental results showed that 1,1,1-TCA could be effectively degraded in 12 h for an initial Fe(0) dosage of 10 g L −1 and a soil/water mass ratio of 1:5. The soil slurry experiments showed two-stage degradation kinetics: a slow reaction in the first stage and a fast reductive degradation of 1,1,1-TCA in the second stage. The reductive degradation of 1,1,1-TCA was expedited as the mass concentration of Fe(0) increased. In addition, high pHs adversely affected the degradation of 1,1,1-TCA over a pH range of 5.4–8.0 and the reductive degradation efficiency decreased with increasing slurry pH. The initial 1,1,1-TCA concentration and the presence of Cl − and SO 4
2− anions had negligible effects. HCO 3
− anions had a accelerative effect on 1,1,1-TCA removal, and both NO 3
− and HA had inhibitory effects. A Cl − mass balance showed that the amount of Cl − ions released into the soil slurry system during the 1,1,1-TCA degradation increased with increasing reaction time, suggesting that the main degradation mechanism of 1,1,1-TCA by Fe(0) in a soil slurry system was reductive dechlorination with 1,1-DCA as the main intermediate. In conclusion, this study provides a theoretical basis for the practical application of the remediation of contaminated sites containing chlorinated solvent.
✓ 已验证
产品关联
DOI
PubMed
高影响因子
MICROCHIMICA ACTA
·
2013
·Vol. 180
·期 11
·1051-1057
·
IF 3.434
Wang Ai-Jun,Guo Han,Zhang Ming,Zhou Dan-Ling,Wang Rui-Zhi,Feng Jiu-Ju
We have developed a simple, sensitive and selective colorimetric method for the detection of cadmium(II) (Cd 2+ ) using gold nanoparticles modified with 4-amino-3-hydrazino-5-mercapto-1,2,4-triazole. Organic solvents or additives are not required. It is found that Cd 2+ induces the aggregation of the modified Au-NPs via chelation, leading to a color change from red to blue. This change can be seen with bare eyes, and monitored by UV–vis spectroscopy, transmission electron microscopy and dynamic light scattering. The detection limit is 30 nM (at a signal-to-noise ratio of 3). The new approach was successfully applied to the detection of Cd 2+ in spiked samples of tap water and lake water, and the results agree well with those obtained by flame atomic absorption spectroscopy.
A simple, sensitive and selective colorimetric method was developed for the detection of Cd 2+ , where 4-amino-3-hydrazino-5-mercapto-1,2,4-triazol (AHMT) modified gold nanoparticles (AuNPs) were used as optical probes. The presence of Cd 2+ induced the aggregation of the AHMT-AuNPs through the chelation process. This approach was successfully applied for the detection of Cd 2+ in spiked samples of tap water and lake water.
✓ 已验证
产品关联
DOI
高影响因子
JOURNAL OF FLUORESCENCE
·
2013
·Vol. 23
·期 5
·989-996
·
IF 1.789
Liu Shikun,Zhang Lili,Gao Jigang,Zhou Jie
A novel probe, 3′,6′ - bis(diethylamino) -2- ((2,4-dimethoxybenzylidene)amino) spiro [isoindoline-1,9′-xanthene]-3-thione (RBS), was designed and synthesized. Its structure was characterized with elemental analysis, IR spectra and 1 H NMR. The probe displayed highly selective and sensitive recognition of Hg 2+ . Reacting with mercury ions in aqueous solution, its fluorescence intensity was enhanced significantly, while its color was changed from colorless to pink. So, a new fluorescence method of detection of Hg 2+ was proposed. Its dynamic response concentration range and detection limit for Hg 2+ were 5.00 × 10 −9 M to 1.00 × 10 −6 M detected and 1.83 × 10 −9 M, respectively. Satisfying results were obtained when the probe was applied to detect spiked Hg 2+ in samples.
✓ 已验证
产品关联
DOI
PubMed
高影响因子
COLLOID AND POLYMER SCIENCE
·
2013
·Vol. 291
·期 9
·2191-2202
·
IF 2.161
Zhao Yingyuan,Du Wei,Sun Limei,Yu Li,Jiao Jingjing,Wang Rui
Calcium carbonate (CaCO 3 ) nanocrystals with controllable polymorph and morphology have been successfully synthesized with the aid of an effective control agent, a halogen-free, low-cost ionic liquid surfactant, 1-butyl-3-methylimidazolium dodecylsulfate ([C 4 mim][C 12 SO 4 ]) in a supersaturated aqueous solution. For the first time, facile preparation of pure lens-like vaterite, sheet-like calcite, and peanut-like aragonite was all achieved in the [C 4 mim][C 12 SO 4 ] aqueous solution through changing the concentration, temperature, and initial pH value and adding magnesium ions. Washed by water and ethanol, all the aggregates were free of [C 4 mim][C 12 SO 4 ] and can be stable at least 1 month in air. The crystal form of the aggregates changed from pure calcite to pure vaterite at room temperature only through increasing [C 4 mim][C 12 SO 4 ] concentration. Formation of the ordered CaCO 3 structures is mainly ascribed to the aggregation of the primary nanoparticles whose formation mechanism is related to the change of supersaturation. This study can provide a facile and environment-friendly method to fabricate CaCO 3 crystal aggregates with various morphologies and polymorphs and can be used for large-scale industrial production and biomimetic synthesis.
✓ 已验证
产品关联
DOI
高影响因子
BIOTECHNOLOGY LETTERS
·
2015
·Vol. 38
·期 1
·81-88
·
IF 1.591
Jiang Jingjie,Bi Huiping,Zhuang Yibin,Liu Shaowei,Liu Tao,Ma Yanhe
Objectives To achieve high production of rosmarinic acid and derivatives in Escherichia coli which are important phenolic acids found in plants, and display diverse biological activities. Results The synthesis of rosmarinic acid was achieved by feeding caffeic acid and constructing an artificial pathway for 3,4-dihydroxyphenyllactic acid. Genes encoding the following enzymes: rosmarinic acid synthase from Coleus blumei , 4-coumarate: CoA ligase from Arabidopsis thaliana , 4-hydroxyphenyllactate 3-hydroxylase from E. coli and d -lactate dehydrogenase from Lactobacillus pentosus , were overexpressed in an l -tyrosine over-producing E. coli strain. The yield of rosmarinic acid reached ~130 mg l −1 in the recombinant strain. In addition, a new intermediate, caffeoyl-phenyllactate (~55 mg l −1 ), was also produced by the engineered E. coli strain. Conclusion This work not only leads to high yield production of rosmarinic acid and analogues, but also sheds new light on the construction of the pathway of rosmarinic acid in E. coli .
✓ 已验证
产品关联
DOI
PubMed
高影响因子
JOURNAL OF POROUS MATERIALS
·
2015
·Vol. 22
·期 5
·1195-1203
·
IF 1.108
Wu Qigang,Xu Rong,Li Jing,Zhang Qi,Zhong Jing,Huang Weiqiu,Gu Xuehong
The compact ZIF-69 membranes have been prepared by seeded growth method for the recovery of gasoline vapor which is a major challenge in the petrochemical industry. The membrane performances for separating N 2 /n-alkane mixtures at various operating conditions (e.g. trans-membrane pressure difference, operating temperature, feed concentration, and stage cut) were systematically investigated. The highest separation factor was 2.60 with the corresponding permeance of 5.02 × 10 −8 mol/(m 2 s Pa) for the N 2 /n-C 6 H 14 model mixtures. Moreover, the effects of n-alkane components (n-C 5 H 12 , n-C 6 H 14 , and n-C 7 H 16 ) on the separation performances were studied, and the separation factors followed α (N 2 /n-C 7 H 16 ) > α (N 2 /n-C 6 H 14 ) > α (N 2 /n-C 5 H 12 ), due to the different adsorption capacities of n-alkanes on ZIF-69 materials. The present work demonstrates that the ZIF-69 membrane is a highly promising candidate for the application in gasoline vapor recovery.
✓ 已验证
产品关联
DOI
高影响因子
MICROCHIMICA ACTA
·
2015
·Vol. 182
·期 11
·1983-1989
·
IF 3.741
Liu Guangyang,Yang Xin,Li Tengfei,Yu Hailong,Du Xinwei,She Yongxin,Wang Jing,Wang Shanshan,Jin Fen,Jin Maojun,Shao Hua,Zheng Lufei,Zhang Yanxin,Zhou Pan
We report on a method for the determination of the herbicide atrazine in tap water samples using melamine-modified gold nanoparticles (Mel-AuNPs). If a solution containing atrazine is added to a solution of such NPs, a color change occurs from wine-red to blue. This is due to a transition from monodisperse to aggregated Mel-AuNPs and caused by strong hydrogen bonding between atrazine and melamine. The color change can be monitored by a UV–vis spectrophotometer or with bare eyes. The ratio of the absorbances at 640 and 523 nm is linearly related to the logarithm of the atrazine concentration in the 0.165 to 16.5 μM range, and (with different slope) in the 16.5 μM to 330 μM range. The detection limit of atrazine is as low as 16.5 nM (S/N = 3). The method was successfully applied to the determination of atrazine in spiked tap water and gave recoveries that ranged from 72.5 % to 102.3 %.
ᅟ
✓ 已验证
产品关联
DOI
高影响因子
JOURNAL OF MATERIALS SCIENCE
·
2015
·Vol. 50
·期 11
·3860-3874
·
IF 2.371
Chen Wen-Qiu,Li Quan-Tao,Li Peng-Hui,Zhang Quan-Yuan,Xu Zu-Shun,Chu Paul K.,Wang Xian-Bao,Yi Chang-Feng
Reduced graphene oxide/polyimide (rGO/PI) nanocomposites are prepared via in situ random co-polycondensation of amino-modified and chemically reduced graphene oxide (rGO-NH 2 ) with commercial diamine and dianhydrides. The chemical modification and reduction of graphene oxide (GO) endows rGO-NH 2 with good solubility in organic solvents to prepare rGO/PI nanocomposites with high filler contents. rGO-NH 2 is further used as a functional co-monomer to participate the polymerization of PI with full compatibility of the guest and host in molecular level. With the addition of rGO-NH 2 at 2 wt% content, the thermal, mechanical properties, and hydrophobicities of rGO/PI nanocomposites are significantly enhanced with various indicators achieving or approaching the optimum. The positive or negative impacts of rGO-NH 2 with various contents to the properties of the obtained nanocomposites are also illustrated incidentally from micromorphology. This effective approach provides a possibility for developing high-performance PI composites based on graphene for advanced engineering or functional materials.
✓ 已验证
产品关联
DOI
高影响因子
JOURNAL OF SOL-GEL SCIENCE AND TECHNOLOGY
·
2015
·Vol. 75
·期 1
·206-214
·
IF 1.532
Shang Qianqian,Zhou Yonghong
Abstract A facile method for the preparation of polystyrene/silica (PS/SiO 2 ) composite microspheres via sol–gel process of tetraethylorthosilicate (TEOS) employing polyvinylpyrrolidone-functionalized monodispersed PS microspheres as template is proposed. Hollow mesoporous silica microspheres containing surface silica nanoparticles are successfully fabricated after the calcination of the composite microspheres. The shell thickness, the size of surface silica nanoparticles and the surface morphology of hollow mesoporous silica microspheres can be readily tailored by adjusting the concentrations of TEOS and ammonia (NH 4 OH). The formation mechanism of the products is detailed through the investigation of the products at different reaction conditions. At the low NH 4 OH/TEOS volume ratio (<1), intact hollow mesoporous silica microspheres with hierarchical raspberry-like structure can be obtained. This synthesis method is simple, straightforward and suitable for the preparation of the other biomineral nanostructures that are unique carriers in drug delivery, biological and catalytic applications. Graphical Abstract
✓ 已验证
产品关联
DOI
高影响因子
COLLOID AND POLYMER SCIENCE
·
2014
·Vol. 293
·期 3
·823-831
·
IF 2.41
Chang Huan,Liu Yan,Shi Mei,Liu Zhaotie,Liu Zhongwen,Jiang Jinqiang
The water-soluble amphiphilic random copolymer of P(DMA- co -VBC) with coumarin pendants has been designed to investigate the photo-induced dynamic association of coumarin pendants within polymer micelles in aqueous solution. Methods of absorption and emission spectra, solution transmittance, dynamic light scattering (DLS), and atomic force microscope (AFM) were applied. It was found that P(DMA- co -VBC) can form polymer micelles in aqueous solution. The time-dependent photo-dimerization degree (PD) of polymer micelles upon different intensity irradiations of 320 nm light showed saturating behaviors with an intensity-independent value of the maximum photo-dimerization extent, while the maximum photo-cleavage extent of coumarin dimers declined with the increasing intensity of 254 nm irradiation at used conditions. Furthermore, a significant emission band at 445 nm ( I
2
) evidently emerged as against the disappearance of emission band at 385 nm ( I
1 ) during the photo-dimerization, and the time-dependent I
2
/I
1 ratios of polymer aqueous solution upon alternative irradiations of 320 and 254 nm light showed a wave-like increase as a function of irradiation cycles, indicating a wavy closeness of coumarin pendants within polymer micelles during the reversible photo-dimerization cycles.
✓ 已验证
产品关联
DOI
高影响因子
JOURNAL OF ELECTRONIC MATERIALS
·
2016
·Vol. 45
·期 3
·1935-1941
·
IF 1.491
Zhang Aijuan,Chen Qiufan,Yao Wei,Yang Dingfeng,Wang Guoyu,Zhou Xiaoyuan
The large-scale colloidal synthesis and thermoelectric (TE) properties of Co-doped Cu 2 SnSe 3 (CCTSe) alloys are investigated for the first time. The TE properties of the CCTSe bulks were measured in the temperature range from 300 K to 715 K. A large increment in the Seebeck coefficient and a dramatic reduction in the lattice thermal conductivity was observed in CCTSe compounds, and the dimensionless TE figure␣of merit ZT reaches a peak value of 0.63 at 715 K. These observations demonstrate an exciting scientific opportunity to raise the figure-of-merit of colloidally synthesized quaternary chalcogenide nanocrystals via optimized doping.
✓ 已验证
产品关联
DOI
高影响因子
TUMOR BIOLOGY
·
2016
·Vol. 37
·期 7
·8609-8619
·
IF 2.926
Xu Jinfeng,Zeng Xinxin,Liu Yingying,Luo Hui,Wei Zhanghong,Liu Huiyu,Zhou Yuli,Zheng Hairong,Zhou Jie,Tan Guanghong,Yan Fei
Ultrasound-targeted microbubble destruction (UTMD) has become a novel gene/drug delivery method in cancer therapeutic application. However, the gene transfection efficiency mediated by UTMD is still unsatisfactory. Here, we introduced iRGD/CCR2 dual-targeted cationic microbubbles (MB iRGD/CCR2 ) which was modified with PEI-600 and coated with iRGD peptides and anti-CCR-2 antibodies. It showed that MB iRGD/CCR2 had a 25.83 ± 1.57 mV surface zeta potential and good stability. The experiments in vitro showed MB iRGD/CCR2 had higher binding efficiency with both bEnd.3 cells and MCF-7 cells than that of iRGD or CCR2 single-targeted cationic microbubbles (MB iRGD or MB CCR2 ) ( P < 0.05 for both). Agarose gel electrophoresis assay showed that MB iRGD/CCR2 can effectively load pGPU6/GFP/Neo-shAKT2 plasmid DNA. Compared with the plain MBs (MB control ) or single-targeted cationic MBs including MB iRGD and MB CCR2 ( P < 0.05 for all), the dual-targeted cationic MB iRGD/CCR2 groups had higher gene transfection efficiency under US exposure. It showed that the dual-targeted cationic MB iRGD/CCR2 has a potential value to be used as an ultrasound imaging probe for ultrasound image-guided tumor gene therapy.
✓ 已验证
产品关联
DOI
PubMed
高影响因子
危险品化学品经营许可证（带存储）