BULLETIN OF ENVIRONMENTAL CONTAMINATION AND TOXICOLOGY
·
2019
·Vol. 103
·期 1
·193-198
·
IF 1.65
Zhang Wenjie,Wang Jun,Wang Jinhua,Zhu Lusheng,Lv Ning,Wang Rui,Ahmad Zulfiqar
The widespread use of pharmaceutical and personal care products (PPCPs) has attracted much attention and the impact of PPCPs on indigenous microbial communities has become increasingly important in recent days. Five common PPCPs, including doxycycline (DOX), ciprofloxacin (CIP), triclocarban (TCC), carbamazepine (CBZ), and sulfadimidine (SMZ), were selected and their effects on soil microbial respiration were studied at concentrations of 0, 0.2, 1, 5, 25 and 50 mg/kg. The results of this study indicate that the effect of five common PPCPs on soil microbial respiration was dose- and time- dependent. At low concentrations (0.2 and 1 mg/kg), CBZ and SMZ exhibited an activation effect on microbial soil respiration at 1 day (58.02%, 26.39% and 1.54%, 1.76% at 0.2 and 1 mg/kg respectively), while DOX showed inhibition for all tested concentrations at 1 day of incubation. At high concentrations (25 and 50 mg/kg) CIP and SMZ showed an inhibitory effect (− 69.13%, − 80.86% for 25 and 50 mg/kg, respectively), while TCC and CBZ exhibited stimulatory effect (38.07%, 9.64% and 4.06%, 12.18% at 25 and 50 mg/kg, respectively) at 1 day of incubation. Our findings indicate that the effect of tested PPCPs on soil microbial respiration had an inhibitory or stimulatory effect based on the dose and extent of time.
研究领域:
环境科学
·
微生物学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
Nanoscale
·
2019
·Vol. 12
·期 2
·591-601
·
IF 6.97
Shuangquan Lai,Yong Jin,Liangjie Shi,Rong Zhou,Yutang Zhou,Dexin An
Despite numerous efforts, the mechanism behind multicolor photoluminescence (PL) in graphene quantum dots (GQDs) is still controversial. A deep insight into the origin of the multicolor emissions in GQDs is quite necessary for modulating their luminescence to facilitate the better use of this fluorescent material. Herein, GQDs with amino, carboxyl, and ammonium carboxylate groups were synthesized. The as-prepared GQDs exhibited intriguing excitation- and concentration-dependent multicolor PL characteristics. By regulating the excitation wavelength or concentration of GQDs, specific luminescence colors including blue, cyan, green, yellow, and even orange can be obtained. Systematic structural and optical studies indicated that the graphene basal plane and different functional groups dominantly exhibited nN 2P–σ*, π–π*, nO 2p–π* (–COOH), nO 2p–π* (–COO−) and nN 2p–π* electronic transitions, which appeared as multi-fluorescent centers that gave rise to the excitation-dependent multicolor PL. The occurrence of different types of electronic transitions and their color emissions were proved by pH-dependent PL measurements. In addition, systematic optical and morphology analyses revealed that GQDs could self-assemble into J-type aggregates with different morphologies and sizes as the concentration increased, and the observed concentration-dependent multicolor PL can be ascribed to aggregation-mediated energy level reconstruction in GQDs. Our findings further suggest that the competition among various fluorescent centers and self-aggregation processes dominated the luminescent properties of GQDs. This work will contribute to understand the origins of excitation- and concentration-dependent multicolor emissions in GQDs, which is also highly instructive for broadening the application fields of GQDs.
研究领域:
材料科学
·
光学
·
化学
✓ 已验证
DOI
PubMed
高影响因子
CRYSTENGCOMM
·
2013
·Vol. 15
·期 41
·8262-8272
·
IF 3.879
Qin Wang,Yunxia Liu,Baocang Liu,ZhanLi Chai,Guangran Xu,ShengLi Yu,Jun Zhang
Cubic α- and hexagonal β-phase lanthanide luminescent NaYF4:Eu3+/Tb3+ nanostructures with diverse morphologies were successfully synthesized via a mild solvothermal method. The effects of the synthetic parameters on the crystal phase structure, size and morphology of NaYF4:Eu3+/Tb3+ nanostructures were systematically investigated. By modifying the synthetic parameters, the crystal phase structure, size and morphology were well controlled, and the phase transition from cubic α- to hexagonal β- can be easily realized. Furthermore, the morphology evolution is revealed, and the surfactant modulating formation mechanisms with diverse morphologies was proposed. The photoluminescence properties were found to be in close correlation with their composition, phase structure and morphology. NaYF4:Eu3+/Tb3+ nanostructures possessing unique morphologies and highly efficient luminescence may find potential applications in optoelectronics, sensors and biolabels.
研究领域:
材料科学
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光学
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纳米技术
✓ 已验证
产品关联
DOI
高影响因子
MRS Advances
·
2019
·Vol. 4
·期 38
·2071-2078
·
IF 0
Zhong Yong,Hu Yaoqing,Wang Jiefei,Wang Jinghan,Ren Xitong,Sun Jiajie,Bai Feng
Photocatalytic water splitting to form hydrogen can effectively alleviate energy and environmental problems attracting wide attention. However, the current photocatalysts have low photocatalytic efficiencies due to the narrow absorption spectrum, which is far from the actual application requirements. Herein, we use the as-prepared zinc porphyrin self-assemblies to visible-light-drive photocatalytic hydrogen evolution with Pt as the cocatalyst and ascorbic acid (AA) as the sacrificial agent. The results exhibit morphology-dependent performance and hexagonal stacks achieved optimal H 2 evolution rate (47.1 mmol/h/g), then followed by nanodiscs, nanorod and tetragonal stacks, meanwhile the nanorods with different aspect ratios show size-dependent properties. The UV-vis absorption and photoluminescence spectra and the shortening of decay time of the corresponding ZnTPyP aggregates reveal that the well-defined self-assembled porphyrin networks are J-aggregation and boost efficient energy transfer with respect to monomer. Such porphyrin self-assemblies are standing for one of the most promising photosensitizers in photocatalysis field and provide an important reference for designing the next generation of hydrogen production.
研究领域:
化学
·
材料科学
·
能源科学
✓ 已验证
产品关联
DOI
Science of Advanced Materials
·
2017
·
IF 1.671
Li Tingting,Li Yuebin,Xu Gai,Du Guihuan,Wang Fei,Han Junbo,Zhang Junpei,Ma Zongwei,Liu Zuli,Yao Kailun
ZnSe:Mn/ZnS core–shell nanocrytals were successfully synthesized via a nucleation-doping strategy assisted with a low-toxicity, high-reactivity, and organic soluble selenium precursor in oleyamine. The as-prepared ZnSe:Mn/ZnS nanocrytals were then investigated by transmission
electron microscopy (TEM), X-ray powder diffraction (XRD), ultraviolet-visible (UV-Vis) absorption spectroscopy, and photoluminescence (PL) spectroscopy. All the results showed that the ZnSe:Mn/ZnS nanocrystals have good monodispersibility and high photoluminescence. Further systematic research
found that injection temperature of 250 °C, three ZnS layers, and Mn doping concentration of 2% are the optimal parameters for the synthesis of high luminescence ZnSe:Mn/ZnS nanocrystals. Additionally, these ZnSe:Mn nanocrystals exhibit temperature- and magnetic field-dependent optical
properties, which show great potential in the application of temperature and magnetic field sensing.
研究领域:
材料科学
·
光学
·
纳米技术
✓ 已验证
DOI
高影响因子
Science of Advanced Materials
·
2016
·Vol. 8
·期 5
·1074-1078
·
IF 1.812
She Boxi,Wan Xuejuan,Tang Jiaoning,Deng Yuanming,Zhou Xiaofeng,Xiao Caihua
Cuprous oxide nanoparticles with diverse morphology and particle size were prepared through reductive solution chemistry routes under alkaline condition. The standard minimal inhibitory concentration (MIC) test against Escherichia coli indicated that both size and morphology
of cuprous oxide nanoparticles played important role in their antibacterial performance. Cuprous oxide nanoparticles with smaller size (∼50 nm) exhibited better antibacterial activity than those with larger size (250∼350 nm); spherical cuprous oxide nanoparticles were found to be superior
to the cubic ones in the bacterial killing process. In addition, the synergistic antibacterial effect of cuprous oxide nanoparticles in the presence of another antibacterial agent, ascorbic acid (AA), was investigated. Experimental results showed that the antibacterial capacity of cuprous
oxide nanoparticles was significantly improved in the presence of ascorbic acid (0.1 wt%). The probable mechanism underlying the synergistic antibacterial activity has been discussed in detail. All the experimental results indicated that the developed low-cost antimicrobial mixture holds promising
application potential.
研究领域:
材料科学
·
微生物学
·
生物医学
✓ 已验证
DOI
高影响因子
JOURNAL OF CHEMICAL THERMODYNAMICS
·
2017
·
IF 2.726
Ying Zhang,Xinxin He,Yutian Chen,Maogang He
The mutual diffusion coefficients of n -butanol + n -heptane and n -pentanol + n -heptane were measured over the mass fraction of n -butanol or n -pentanol from 0.05 to 0.95 at intervals of 0.10 and the temperatures 288.15 K, 298.15 K, 308.15 K and 318.15 K at 0.101 MPa. The measurements were carried out using a digital holographic interferometry system. The expanded relative uncertainty of the mutual diffusion coefficients was estimated to be less than 2.4%. The influences of temperature and composition on the mutual diffusion coefficients were investigated. Moreover, equations for the mutual diffusion coefficients of the two binary mixtures were fitted to the data as functions of mass fraction and temperature. The correlations represent the data with the absolute average of relative deviations (AARDs) of 1.1% for n -butanol + n -heptane and 0.77% for n -pentanol + n -heptane, respectively.
研究领域:
物理化学
·
热力学
·
传递现象
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溶液化学
·
流体混合物
✓ 已验证
DOI
高影响因子
RSC Advances
·
2016
·Vol. 6
·期 87
·84426-84438
·
IF 3.289
Bei Miao,Jingjing Liu,Xiao Zhang,Junyong Lu,Shaobo Tan,Zhicheng Zhang
Poly(vinylidene fluoride) (PVDF) based ferroelectric fluoropolymers have attracted considerable attention in high energy density pulse capacitors application for the tunable and tight composition dependence of their ferroelectric performances. Grafting poly(methacrylate esters) (ca. poly(methyl methacrylate) (PMMA)) onto the side chain of P(VDF-TrFE-CTFE) (TrFE refers to trifluoroethyelene and CTFE is chlorotrifluoroethylene) has been shown to be an effective route to tailor the ferroelectric performance of P(VDF-TrFE-CTFE). The resultant grafted copolymers possess advantages including well maintained high energy density and remarkably reduced energy loss. To further disclose the influence of a PMMA side chain on ferroelectric relaxation of a P(VDF-TrFE-CTFE) main chain, a set of P(VDF-TrFE-CTFE)-g-PMMA copolymers bearing PMMA content from 10 wt% to 32 wt% were synthesized and well characterized in this work. The dielectric and energy storage performance of the grafted copolymers were systematically investigated under increased electric field, testing temperature, and frequency. The PMMA side chain was found to exhibit great influence with ferroelectric performance under varied conditions by impeding crystallization and formation of the ferroelectric phase of the P(VDF-TrFE-CTFE) main chain along with increasing the Young's modulus of amorphous phase. As a result, the grafted copolymer with optimized PMMA content shows excellent stability with testing frequency, temperature, and electric field. That allows them to store and discharge energy consistently, which is rather important for energy storage capacitors working under varied conditions. With respect to promising energy storage performances together with low performance dependence during working conditions, the PMMA grafted P(VDF-TrFE-CTFE) copolymer may offer a great candidate material for high energy density pulse capacitors.
研究领域:
材料科学
·
高分子化学
✓ 已验证
DOI
高影响因子
MOLECULAR BIOLOGY REPORTS
·
2022
·Vol. 49
·期 6
·4607-4617
·
IF 2.742
Zhang Yimin,Chen Jingqin,Fang Wenxuan,Liang Kaoyun,Li Xiaoning,Zhang Fan,Pang Yuzhou,Fang Gang,Wang Xueni
Purpose Kaempferol is a natural flavonoid that has been reported to be active against many cancers, including prostate cancer, breast cancer and colon cancer. In our previous study, we found kaempferol could act as a selective androgen receptor modulator, thereby suppress development of benign prostatic hyperplasia. This finding inspired us to further explore the effect and the mechanism of action of kaempferol on prostate cancer. Methods Plate clone formation assay was performed to detect the effect of kaempferol on cell proliferation. Flow cytometry was used to detect the impact of kaempferol on cell apoptosis and cell cycle distribution. qPCR, immunofluorescence staining, and enzyme-linked immunosorbent assay were used to detect the expression of gene and protein of Ki67 which is a biomarker of cell proliferation. Results In the present study, we found kaempferol could dramatically suppress androgen-dependent and androgen-independent prostate cancer cells proliferation and induce their apoptosis. Furthermore, we found that kaempferol induced cell cycle to be arrested at G1 phase in 22Rv1 cells but at S and G2 phase in PC-3 cells. In addition, we detected the mRNA and protein of Ki67 which is corresponding to the cell proliferation and found that kaempferol could significantly inhibit Ki67 expression at mRNA level but increase its expression at protein levels in both androgen-dependent and androgen-independent prostate cancer cells. Conclusion Taken together, kaempferol inhibited the proliferation of androgen-dependent and androgen-independent prostate cancer cells by regulating the expression of Ki67. These findings further shed light on the mechanism of action of kaempferol on anti-prostate cancer.
研究领域:
肿瘤学
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药理学
·
分子生物学
·
细胞生物学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
Sustainability
·
2022
·Vol. 14
·期 19
·12872
·
IF 3.889
Zihan Lang,Lidong Xue
Triclosan (TCS) has been widely employed as active ingredient in household products and has received attention for its hepatotoxicity, endocrine disruption and disturbance on immune function. Polylactic acid (PLA) has been highlighted as an alternative biodegradable microplastic, and the knowledge about the adsorption affinity towards TCS is limited. In this study, the ability to act as carrier of TCS by PLA and non-biodegradable microplastics, including polystyrene (PS), polyvinyl chloride (PVC) and polyethylene (PE) with different particle sizes were explored. The influence factors (e.g., dosage, pH and salinity), adsorption kinetics and isotherms were also investigated. Batch experiment results indicated that the TCS adsorption onto PLA and non-biodegradable microplastics exhibited a pronounced pH-dependent pattern (pH of 4, 7 and 10), and the adsorption capacity decreased gradually as pH increased. Furthermore, the adsorption capacity of TCS on PS, PVC and PE decreased as salinity increased from 0 to 3.5%, while no significant inhibition for the sorption capacity of PLA was observed. The adsorption kinetic data of TCS was best fitted with the pseudo-second order model. The Freundlich model with R2(0.999) was suitable to describe the adsorption isotherms of TCS on PLA, while the isotherms data of TCS on PS, PVC and PE was fitted by linear and Freundlich model. The higher adsorption capacity of PLA (38.6 mg g−1) compares to those of PS, PVC and PE (31.3, 11.4 and 9.64 mg g−1, respectively), illustrated by the fact that the physicochemical properties of microplastics have a noticeable impact on adsorption process, and the biodegradable PLA is a stronger vector than the non-biodegradable microplastics.Keywords:triclosan;polylactic acid;vector;pH-dependent
研究领域:
环境科学
·
材料科学
✓ 已验证
产品关联
DOI
高影响因子
Nanomaterials
·
2021
·Vol. 11
·期 12
·3310
·
IF 5.076
Yijie Xia,Shuaishuai Du,Pengju Huang,Luchao Wu,Siyu Yan,Weizhi Wang,Gaoyu Zhong
The temperature-dependent photoluminescence (PL) properties of an anti-perovskite [MnBr4]BrCs3sample in the temperature range of 78–500 K are studied in the present work. This material exhibits unique performance which is different from a typical perovskite. Experiments showed that from room temperature to 78 K, the luminous intensity increased as the temperature decreased. From room temperature to 500 K, the photoluminescence intensity gradually decreased with increasing temperature. Experiments with varying temperatures repeatedly showed that the emission wavelength was very stable. Based on the above-mentioned phenomenon of the changing photoluminescence under different temperatures, the mechanism is deduced from the temperature-dependent characteristics of excitons, and the experimental results are explained on the basis of the types of excitons with different energy levels and different recombination rates involved in the steady-state PL process. The results show that in the measured temperature range of 78–500 K, the steady-state PL of [MnBr4]BrCs3had three excitons with different energy levels and recombination rates participating. The involved excitons with the highest energy level not only had a high radiative recombination rate, but a high non-radiative recombination rate as well. The excitons at the second-highest energy level had a similar radiative recombination rate to the lowest energy level excitons and a had high non-radiative recombination rate. These excitons made the photoluminescence gradually decrease with increasing temperature. This may be the reason for this material’s high photoluminescence efficiency and low electroluminescence efficiency.Keywords:[MnBr4]BrCs3;temperature-dependent;photoluminescence;excitons
研究领域:
材料科学
·
光学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
JOURNAL OF ALLOYS AND COMPOUNDS
·
2020
·
IF 4.65
Xin Chen,Linwen Jiang,Luhui Zhou,Mingyu He,Jiangtao Li,Anhua Wu,Hongbing Chen
The Er 3+ @Yb 3+ co-doped SrAl 2 B 2 O 7 phosphors were prepared by a sol-gel auto-combustion method. The components, microstructure and up-conversion (UC) properties of samples were investigated systematically. The phosphors emitted red light and green light under the excitation of 980 nm wavelength. The intensity of red emission and green emission nearly linearly decreased with increasing ambient temperatures. The red emission, green emission and their intensity ratio as a function of Er 3+ concentrations and Yb 3+ concentrations were studied in detail. The results show that 4.0% Er 3+ and 8.0% Yb 3+ doped samples can obtain the best luminescence intensity while the best light purity cannot be obtained simultaneously. The intensity of red and green emission was measured as a function of excitation power. It indicates that there was no photon avalanche mechanism for SrAl 2 B 2 O 7 : Er 3+ @Yb 3+ due to the absence of sharp change of n values. The UC luminescence corresponded to a two-photon absorption process which was illustrated by the energy transfer mechanism and the steady-state rate equations. Because of the controllable monochromatic luminescence and excellent temperature-dependent luminescence properties, the SrAl 2 B 2 O 7 : Er 3+ @Yb 3+ phosphors have potential application in the fields of non-contact temperature measurement and bio-polychromatic label.
研究领域:
材料科学
·
光学
✓ 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）