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991.
A highly specific immunoassay for microcystin-LR detection based on a monoclonal antibody 总被引:1,自引:0,他引:1
Microcystins (MC) are cyanobacterial hepatotoxins responsible for animal-poisoning and human health incidents. Immunoassays provide a sensitive and fast means to detect these toxins, but cross-reactivity (CR) characteristic of different antibodies was variable. Here, we have produced and characterized a monoclonal antibody (Clone MC8C10) with highly specificity against the most frequent and most toxic variant of microcystins, MC-LR. MC8C10 is more specific against MC-LR among the reported antibodies before. The immunogen was synthesized from the modified MC-LR and bovine serum albumin (BSA). An indirect competitive enzyme-linked immunosorbent assay (ic-ELISA) with MC8C10 was established to detect the MCs in waters, which showed highly specificity with MC-LR, and have a detection limit for MC-LR 0.1 μg L−1, the 50% inhibition concentration (IC50) for MC-LR was 1.8 ± 0.1 μg L−1 and the quantitative detection range was from 0.3 to 10 μg L−1. The [4-arginine] microcystins and the nodularin-R showed lower cross-reactivates (CR < 10%), and other MCs such as MC-LF and MC-LW are not recognized (CR < 10−4). The analysis results of real water samples with ic-ELISA showed that all the coefficients of variation were less than 15%, and the recovery was (100.3 ± 5.9)%. So the highly specific ic-ELISA will commendably suit for sensitive analysis for MC-LR in surface water as well as drinking water. 相似文献
992.
N,P‐Codoped Carbon Networks as Efficient Metal‐free Bifunctional Catalysts for Oxygen Reduction and Hydrogen Evolution Reactions 下载免费PDF全文
Dr. Jintao Zhang Prof. Liangti Qu Prof. Gaoquan Shi Jiangyong Liu Prof. Jianfeng Chen Prof. Liming Dai 《Angewandte Chemie (International ed. in English)》2016,55(6):2230-2234
The high cost and scarcity of noble metal catalysts, such as Pt, have hindered the hydrogen production from electrochemical water splitting, the oxygen reduction in fuel cells and batteries. Herein, we developed a simple template‐free approach to three‐dimensional porous carbon networks codoped with nitrogen and phosphorus by pyrolysis of a supermolecular aggregate of self‐assembled melamine, phytic acid, and graphene oxide (MPSA/GO). The pyrolyzed MPSA/GO acted as the first metal‐free bifunctional catalyst with high activities for both oxygen reduction and hydrogen evolution. Zn–air batteries with the pyrolyzed MPSA/GO air electrode showed a high peak power density (310 W g?1) and an excellent durability. Thus, the pyrolyzed MPSA/GO is a promising bifunctional catalyst for renewable energy technologies, particularly regenerative fuel cells. 相似文献
993.
Transfer of Two‐Dimensional Oligonucleotide Patterns onto Stereocontrolled Plasmonic Nanostructures through DNA‐Origami‐Based Nanoimprinting Lithography 下载免费PDF全文
Yinan Zhang Prof. Jie Chao Prof. Huajie Liu Fei Wang Prof. Shao Su Bing Liu Prof. Lan Zhang Dr. Jiye Shi Prof. Lihua Wang Prof. Wei Huang Prof. Lianhui Wang Prof. Chunhai Fan 《Angewandte Chemie (International ed. in English)》2016,55(28):8036-8040
The precise functionalization of self‐assembled nanostructures with spatial and stereocontrol is a major objective of nanotechnology and holds great promise for many applications. Herein, the nanoscale addressability of DNA origami was exploited to develop a precise copy‐machine‐like platform that can transfer two‐dimensional oligonucleotide patterns onto the surface of gold nanoparticles (AuNPs) through a deliberately designed toehold‐initiated DNA displacement reaction. This strategy of DNA‐origami‐based nanoimprinting lithography (DONIL) demonstrates high precision in controlling the valence and valence angles of AuNPs. These DNA‐decorated AuNPs act as precursors in the construction of discrete AuNP clusters with desired chirality. 相似文献
994.
Size Fractionation of Two‐Dimensional Sub‐Nanometer Thin Manganese Dioxide Crystals towards Superior Urea Electrocatalytic Conversion 下载免费PDF全文
Dr. Sheng Chen Dr. Jingjing Duan Anthony Vasileff Prof. Shi Zhang Qiao 《Angewandte Chemie (International ed. in English)》2016,55(11):3804-3808
A universal technique has been proposed to sort two‐dimensional (2D) sub‐nanometer thin crystals (manganese dioxide MnO2 and molybdenum disulfide MoS2) according to their lateral dimensions. This technique is based on tuning the zeta potential of their aqueous dispersions which induces the selective sedimentation of large‐sized 2D crystals and leaves the small‐sized counterparts in suspension. The electrocatalytic properties of as‐obtained 2D ultrathin crystals are strongly dependent on their lateral size. As a proof‐of‐concept study, the small‐sized MnO2 nanocrystals were tested as the electrocatalysts for the urea‐oxidation reaction (UOR), which showed outstanding performance in both half reaction and full electrolytic cell. A mechanism study reveals the enhanced performance is associated with the remarkable structural properties of MnO2 including ultrathin (ca. 0.95 nm), laterally small‐sized (50–200 nm), and highly exposed active centers. 相似文献
995.
996.
Yunxi Shi Yixi Cai Xiaohua Li Hui Xu Weijun Li Xiaoyu Pu 《Plasma Chemistry and Plasma Processing》2016,36(3):783-797
An experimental study of the regeneration of diesel particulate filter (DPF) was conducted through the use of a self-designed Non-thermal plasma (NTP) injection system with an experimental temperature of 20–300 °C, with atmospheric air being used as the gas source. The results revealed that the PM could be broken down into CO and CO2 by NTP, through a discharge reaction of the NTP reactor. As the temperature increases, the mass of C1 (mass of C in CO) showed an overall declining trend. Interestingly, the mass of C2 (mass of C in CO2) and C12 (the sum of C1 and C2) both showed an initial increase, followed by a decrease. The peak mass of C12 appears at 150 °C, and both axial and radial temperature gradients are less than the limit of DPF temperature gradient at this temperature. In conclusion, DPF can be regenerated by the NTP technology at a lower temperature, which can aid in the avoidance of thermal damage of DPF. The technology boasts a great advantage in adopting atmospheric air as its gas source, which can not only reduce costs, but also is convenient. 相似文献
997.
Yanhong Liu Wei He Zehui Yang Yanwen Chen Xinwei Wang Ling Shi Dongcai Guo 《Research on Chemical Intermediates》2016,42(2):425-438
Amide-type podands derived from N,N′-(ethane-1,2-diyl)bis(2-hydroxybenzamide) and 2-chloro-N-phenylacetamide (substituted with methyl, methoxy, chlorine, nitrogen) were synthesized. Solid complexes of europium nitrate with podands were also synthesized and characterized by elemental analysis, ethylenediaminetetraacetic acid (EDTA) titrimetric analysis, thermal analysis, molar conductivity analysis, and infrared (IR) and ultraviolet–visible (UV–Vis) spectra analysis. The fluorescent properties of the europium(III) [Eu(III)] complexes in a solid state were also investigated. Under excitation of UV light, target Eu(III) complexes exhibited characteristic europium ion emissions. The influence of the substituent on the fluorescence intensity was discussed. Electrochemical properties were also investigated and discussed. 相似文献
998.
The carboranylpyrrole polymers are functional materials with superior thermal resistance and conducting performances. The carboranylpyrrole structures and Laplacian bond order (LBO) of carborane moiety, as well as the thermal resistance and conducting properties of carboranylpyrrole dimers or polymers, were investigated theoretically. The 11B NMR chemical shifts of 3-(2-methyl-o-carboranyl)alkyl-1H-pyrrole monomers (CP-1 to CP-5) were calculated and analyzed. The average LBO values of some characteristic chemical bonds in the carborane cages of CP-1 to CP-5 molecules were calculated. It is found that the average LBO values of carborane moieties change slightly with the increase in alkyl chain length. The temperature resulting in about 15–20 % weight loss for CP-1, CP-3, CP-4 and CP-5 polymers is predicted to be more than 700 °C. Apart from the C–C bonds in carborane moieties of 3-(2-R-o-carboranyl)propyl-1H-pyrrole (R = CH2OH, CH2OCH3, CN, COCl, Ph) substituents, the LBO values of other bonds in these cages change slightly relative to that in the molecule of 3-(2-methyl-o-carboranyl)propyl-1H-pyrrole (CP-3). The C–C bond LBO values in the carborane cages of these substituents with electron-donating groups (R = CH2OH, CH2OCH3) are bigger than that in CP-3, while those values in those substituents with electron-withdrawing groups (R = CN, COCl, Ph) are smaller than that in CP-3. The polymerization activity calculated for CP-1 to CP-5 monomers increases with the increase in alkyl chain length. The calculated orbital energy gap (?E LUMO?HOMO) of CP-1 to CP-5 dimers decreases with the increase in alkyl chain length, and accordingly, the electronic conductivity has the potential to increase. In addition, the calculated band gaps of CP-1 to CP-5 dimers cell models also decrease with the increase in alkyl chain length. 相似文献
999.
Improvement of the Water Resistance of a Narrow‐Band Red‐Emitting SrLiAl3N4:Eu2+ Phosphor Synthesized under High Isostatic Pressure through Coating with an Organosilica Layer 下载免费PDF全文
Dr. Yi‐Ting Tsai Dr. Hoang‐Duy Nguyen Dr. Agata Lazarowska Dr. Sebastian Mahlik Prof. Dr. Marek Grinberg Prof. Dr. Ru‐Shi Liu 《Angewandte Chemie (International ed. in English)》2016,55(33):9652-9656
A SrLiAl3N4:Eu2+ (SLA) red phosphor prepared through a high‐pressure solid‐state reaction was coated with an organosilica layer with a thickness of 400–600 nm to improve its water resistance. The observed 4f65d→4f7 transition bands are thought to result from the existence of Eu2+ at two different Sr2+ sites. Luminescence spectra at 10 K revealed two zero‐phonon lines at 15377 (for Eu(Sr1)) and 15780 cm?1 (for Eu(Sr2)). The phosphor exhibited stable red emission under high pressure up to 312 kbar. The configurational coordinate diagram gave a theoretical explanation for the Eu2+/3+ result. The coated samples showed excellent moisture resistance while retaining an external quantum efficiency (EQE) of 70 % of their initial EQE after aging for 5 days under harsh conditions. White‐light‐emitting diodes of the SLA red phosphor and a commercial Y3Al5O12:Ce3+ yellow phosphor on a blue InGaN chip showed high color rendition (CRI=89, R9=69) and a low correlated color temperature of 2406 K. 相似文献
1000.
Regioselective Amine–Borane Cyclization: Towards the Synthesis of 1,2‐BN‐3‐Cyclohexene by Copper‐Assisted Triazole/Gold Catalysis 下载免费PDF全文
Stephen E. Motika Dr. Qiaoyi Wang Dr. Novruz G. Akhmedov Dr. Lukasz Wojtas Prof. Dr. Xiaodong Shi 《Angewandte Chemie (International ed. in English)》2016,55(38):11582-11586
The combination of triazole/gold (TA‐Au) and Cu(OTf)2 is identified as the optimal catalytic system for promoting intramolecular hydroboration for the synthesis of a six‐membered cyclic amine–borane. Excellent yields (up to 95 %) and regioselectivities (5‐exo vs. 6‐endo) were achieved through catalyst control and sequential dilution. Good functional‐group tolerance was attained, thus allowing the preparation of highly functionalized cyclic amine–borane substrates, which could not be achieved using other methods. Deuterium‐labeling studies support the involvement of a hydride addition to a gold‐activated alkyne with subsequent C?B bond formation. 相似文献