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961.
Chun‐Feng Wang Dr. Ren‐Fu Li Prof. Dr. Xue‐Yuan Chen Dr. Rong‐Jia Wei Prof. Dr. Lan‐Sun Zheng Prof. Dr. Jun Tao 《Angewandte Chemie (International ed. in English)》2015,54(5):1574-1577
Hybrid materials integrated with a variety of physical properties, such as spin crossover (SCO) and fluorescence, may show synergetic effects that find applications in many fields. Herein we demonstrate a promising post‐synthetic approach to achieve such materials by grafting fluorophores (1‐pyrenecarboxaldehyde and Rhodamine B) on one‐dimensional SCO FeII structures. The resulting hybrid materials display expected one‐step SCO behavior and fluorescent properties, in particular showing a coupling between the transition temperature of SCO and the temperature where the fluorescent intensity reverses. Consequently, synergetic effect between SCO and fluorescence is incorporated into materials despite different fluorophores. This study provides an effective strategy for the design and development of novel magnetic and optical materials. 相似文献
962.
Realizing both High Energy and High Power Densities by Twisting Three Carbon‐Nanotube‐Based Hybrid Fibers 下载免费PDF全文
Ye Zhang Yang Zhao Dr. Xunliang Cheng Dr. Wei Weng Jing Ren Xin Fang Yishu Jiang Peining Chen Zhitao Zhang Prof. Yonggang Wang Prof. Huisheng Peng 《Angewandte Chemie (International ed. in English)》2015,54(38):11177-11182
Energy storage devices, such as lithium‐ion batteries and supercapacitors, are required for the modern electronics. However, the intrinsic characteristics of low power densities in batteries and low energy densities in supercapacitors have limited their applications. How to simultaneously realize high energy and power densities in one device remains a challenge. Herein a fiber‐shaped hybrid energy‐storage device (FESD) formed by twisting three carbon nanotube hybrid fibers demonstrates both high energy and power densities. For the FESD, the energy density (50 mWh cm?3 or 90 Wh kg?1) many times higher than for other forms of supercapacitors and approximately 3 times that of thin‐film batteries; the power density (1 W cm?3 or 5970 W kg?1) is approximately 140 times of thin‐film lithium‐ion battery. The FESD is flexible, weaveable and wearable, which offers promising advantages in the modern electronics. 相似文献
963.
The aim of this research was to determine the chemical composition, antioxidant and antibacterial properties of the essential oils from Cynanchum chinense and Ligustrum compactum and isolation of antioxidant and antibacterial constituents from the essential oils. Thirty-eight components were identified in essential oils. Based on bioactivity-guided fractionation, guaiacol, linalool and 2-phenylethanol were isolated and identified as active constituents. Both L. compactum flower oil and 2-phenylethanol showed high antibacterial performance, with inhibition zone from 22.8 ± 0.8 to 11.9 ± 2.0 mm at highest concentration, and minimum inhibitory concentration values ranging from 0.25% to 1%. In both DPPH and ABTS assay, the active constituent guaiacol (IC50 = 4.15 ± 0.72 and 9.12 ± 0.98 μg mL? 1, respectively) exhibited high antioxidant activity, and the oils showed moderate antioxidant activity. These results indicate potential efficacy of active constituents and essential oils of L. compactum and C. chinense to control food-borne pathogenic and spoilage bacteria. 相似文献
964.
Yuanyuan Zheng Xuesong Wang Sumei Gao Min Ma Guiming Ren Huabing Liu 《Natural product research》2015,29(19):1804-1810
In the present study, using chalcone as a lead compound, a series of its derivatives (compounds 1–30) were designed and synthesised. Their activity of anti-pathogenic fungi of plants has been evaluated. It is found that these compounds have good antifungal activity against Sclerotinia sclerotiorum, Helminthosprium maydis, Botrytis cinerea, Rhizoctonia solani and Gibberella zeae. Among them, the inhibition of growth for compound 30 against S. sclerotiorum showed 89.9%, with the median effective concentrations (EC50) of 15.4 μg mL? 1. The inhibition of growth for compounds 28, 29 and 30 at a concentration of 100 μg mL? 1 against H. maydis is 90.3%, 90.7% and 91.1%, with EC50 of 15.1, 18.3 and 18.1μg mL? 1, respectively. 相似文献
965.
Preparation of 17β‐estradiol‐imprinted material by surface‐initiated atom transfer radical polymerization and its application 下载免费PDF全文
Yanru Gong Yuling Niu Xiaohan Gong Meihua Ma Xiaowei Ren Weihua Zhu Ruiming Luo Bolin Gong 《Journal of separation science》2015,38(7):1254-1261
A novel 17β‐estradiol molecularly imprinted polymer was grafted onto the surface of initiator‐immobilized silica by surface‐initiated atom transfer radical polymerization. The resulting molecularly imprinted polymer was characterized by elemental analysis and thermogravimetric analysis. The binding property of molecularly imprinted polymer for 17β‐estradiol was also studied with both static and dynamic methods. The results showed that the molecularly imprinted polymer possessed excellent recognition capacity for 17β‐estradiol (180.65 mg/g at 298 K), and also exhibited outstanding selectivity for 17β‐estradiol over the other competitive compounds (such as testosterone and progesterone). Then, the determination of trace 17β‐estradiol in beef samples was successfully developed by using molecularly imprinted polymer solid‐phase extraction coupled with high‐performance liquid chromatography. The limit of detection was 0.25 ng/mL, and the amount of 17β‐estradiol in beef samples was detected at 2.83 ng/g. This work proposed a sensitive, rapid, reliable, and convenient approach for the determination of trace 17β‐estradiol in complicated beef samples. 相似文献
966.
Study of the matrix effects of tetrodotoxin and its content in cooked seafood by liquid chromatography with triple quadrupole mass spectrometry 下载免费PDF全文
Xin‐wei Yu Meiling Lu Bai‐fen Huang Yi‐ping Ren 《Journal of separation science》2015,38(19):3374-3382
Tetrodotoxin is a marine biotoxin with high acute toxicity. The levels in cooked seafood will help us to assess its intake in humans and may help assess the risk of toxicity. However, heavy matrices hinder the direct quantitation of tetrodotoxin. A quantitative method of measuring tetrodotoxin in cooked seafood using liquid chromatography with triple quadrupole mass spectrometry was established in this study. Tetrodotoxin was extracted from the sample matrix using 2% formic acid in methanol and cleaned using a cation exchange cartridge. The cleanup conditions were optimized. The matrix effects were determined using the postextraction spiking method and by comparing the slope of the linear regression equation in sample matrix to that in solvent. The limit of detection in the sample matrix was 5 μg/kg and the limit of quantification was 10 μg/kg. The mean recoveries at three spiking levels were 66.9–89.2% with relative standard deviations of 5.0–10.8% (n = 6) in five different matrices. Tetrodotoxin was found at concentrations of 26.1–2462 μg/kg in nine of 83 cooked seafoods tested in this study. Eight analogs of Tetrodotoxin were detected in the samples studied. 相似文献
967.
968.
Zhijun Zhang Yijia Guan Meng Li Andong Zhao Jinsong Ren Xiaogang Qu 《Chemical science》2015,6(5):2822-2826
Sandwich ELISA methods have been widely used for biomarker and pathogen detection because of their high specificity and sensitivity. However, the main drawbacks of this assay are the cost, the time-consuming procedure for the isolation of antibodies and their poor stability. To overcome these restrictions, we herein fabricated artificial antibodies based on imprinting technology and developed a sandwich ELISA for pathogen detection. Both the capture and detection antibodies were obtained via an in situ method, with simplicity, rapidity and low cost. The peroxidase mimics, the CeO2 nanoparticles, as signal generators were integrated with the detection antibody. The fabricated artificial antibodies exhibited not only natural antibody-like binding affinities and selectivities, but also superior stability and reusability. The detection limit was about 500 CFU mL–1, which is much lower than that of traditional ELISA methods (104 to 105 CFU mL–1). Furthermore, the capture antibody can disinfect pathogens in situ. 相似文献
969.
Dr. Yi Jiang Lei-Li Sun Guang-Zong Ren Xiang Niu Wen-zhou Hu Prof. Zhi-Qiang Hu 《ChemistryOpen》2015,4(3):378-382
The development of novel selective probes with high sensitivity for the detection of Al3+ is widely considered an important research goal due to the importance of such probes in medicine, living systems and the environment. Here, we describe a new fluorescent probe, N′-(4-diethylamino-2-hydroxybenzylidene)-2-hydroxybenzohydrazide (1), for Al3+. Probe 1 was evaluated in a solution of acetonitrile/water (1:1 v/v). Compared with previously reported probes for Al3+, probe 1 can be synthesized easily and in high yield. A Job plot confirmed that probe 1 is able to complex Al3+ in a 1:1 ratio, and the binding constant was determined to be 4.25×108 m−1. Moreover, the detection limit was as low as 6.7×10−9 m, suggesting that probe 1 has a high sensitivity. Common coexistent metal ions, such as K+, Co2+, Ca2+, Ba2+, Ni2+, Pb2+, Hg2+, Ce2+, Zn2+, Cd2+, Fe3+, showed little or no interference in the detection of Al3+ in solution, demonstrating the high selectivity of the probe. Finally, the ability of probe 1 to act as a fluorescent probe for Al3+ in living systems was evaluated in Gram-negative bacteria, Escherichia coli, and confocal laser scanning microscopy confirmed its utility. The results of this study suggest that 1 has appropriate properties to be developed for application as a fluorescent probe of Al3+ for use in biological studies. 相似文献
970.
Ruopeng Li Qiang Peng Bing Han Yuanyu Ke Xin Wang Xubing Lu Xueyuan Wu Jiantao Kong Zhifeng Ren Eser Metin Akinoglu Michael Giersig Guofu Zhou Jun‐Ming Liu Krzysztof Kempa Jinwei Gao 《Laser \u0026amp; Photonics Reviews》2016,10(3):465-472
We demonstrate a high optoelectronic performance and application potential of our random network, with subwavelength diameter, ultralong, and high‐quality silver nanowires, stabilized on a substrate with a UV binder. Our networks show very good optoelectronic properties, with the single best figure of merit of ∼1686, and excellent stability under harsh mechanical strain, as well as thermal, and chemical challenge. Our network transparency strongly exceeds the simple shading limit. We show that this transmission enhancement is due to plasmonic refraction, which in an effective medium picture involves localized plasmons, and identify the inhomogeneous broadening as the key factor in promoting this mechanism. Such networks could become a basis for a next generation of ultrahigh‐performance transparent conductors.