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91.
Chen Yanni Liu Liqiang Xu Liguang Song Shanshan Kuang Hua Cui Gang Xu Chuanlai 《Nano Research》2017,10(8):2833-2844
A gold immunochromatographic sensor (GICS) was developed for the rapid detection of 26 sulfonamides in honey samples.The sensor was based on a group-specific monoclonal antibody (mAb) that can recognize all 26 sulfonamides.Three haptens (hapten 1 with a thiazole ring,hapten 2 with a benzene ring,and hapten 3 with a straight carbon chain) were used for antigen preparation.With hybridoma technology,a group-specific mAb was screened with a 50% maximal inhibitory concentration (IC50) against sulfathizole (STZ) and the other 25 analogues ranging from 0.08 to 90.18 ng/mL.Mono-dispersed gold nanoparticles were conjugated with the mAb to develop the lateral immunochromatographic strip.A labeled antibody concentration of 0.1 μg/mL and a coating antigen concentration of 0.2 μg/mL in the test line were chosen for strip preparation.Under optimized conditions,the visual limits of detection (vLOD) for the concentrations of STZ,sulfamethoxazole,sulfamethizole,sulfadiazine,sulfamerazine,sulfadimethoxine,sulfamonomethoxine,sulfameter,sulfamethoxypyridazine,and sulfachloropyridazine were 5,0.25,0.25,10,5,10,25,2.5,5,0.25,and 10 μg/kg,respectively.Scanner analysis in honey samples revealed good performance for detection of the 26 sulfonamides.Commercial honey samples were tested with the sensor and positive results were confirmed with high-performance liquid chromatography.The proposed strip sensor provides a convenient method for the rapid and reliable determination of sulfonamides pollutants in honey samples. 相似文献
92.
Juan Peng Liqiang Liu Liguang Xu Shanshan Song Hua Kuang Gang Cui Chuanlai Xu 《Nano Research》2017,10(1):108-120
For rapid and simultaneous detection of (fluoro)quinolones, a broadly specific monoclonal antibody (mAb) that recognizes 32 (fluoro)quinolone antibiotics was prepared using a mixture of a norfloxacin derivative and a sarfloxacin derivative as the hapten. An immunochromatographic strip based on gold nanoparticles (AuNPs) was then assembled with goat anti-mouse antibody and antigen (sarfloxacin coupled to ovalbumin), used to form the C line and T line, respectively. This antigen competes with the (fluoro)quinolones in a sample incubated with mAbs labeled with AuNPs. The strip can detect 32 (fluoro)quinolones including oxolinic acid, nalidixic acid, miloxacin, pipemidic acid, piromidic acid, rosoxacin, cinoxacin, norfloxacin, pefloxacin, lomfloxacin, enofloxacin, fleroxacin, ciprofloxacin, enrofloxacin, dafloxacin, orbifloxacin, sparfloxacin, gemifloxacin, besifloxacin, balofloxacin, gatifloxacin, moxifloxacin, nadifloxacin, ofloxacin, marbofloxacin, flumequine, pazufloxacin, prulifloxacin, sarafloxacin, difloxacin, trovafloxacin, and tosufloxacin in milk within 10 min with the naked eye. The cut-off values of the strip range from 1 to 100 ng/mL and the limits of detection are 0.1–10 ng/mL. The strip does not cross-react with antibiotics including tetracycline, sulfamethazine, ampicillin, erythromycin, aflatoxin B1, or gentamicin. In short, this immunochromatographic strip is a very useful tool for the primary screening of (fluoro)quinolones in milk. 相似文献
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Highly Efficient Perovskite Nanocrystal Light‐Emitting Diodes Enabled by a Universal Crosslinking Method 下载免费PDF全文
96.
Phototherapy: Hierarchical Plasmonic Nanorods and Upconversion Core–Satellite Nanoassemblies for Multimodal Imaging‐Guided Combination Phototherapy (Adv. Mater. 5/2016) 下载免费PDF全文
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98.
Sen Zeng Guoqi Ni Xiaojun Kuang 《Journal of Materials Science: Materials in Electronics》2016,27(10):10078-10081
High-Q dielectric materials ilmenite MgTiO3, columbite MgNb2O6 and cubic perovskite Ba3NiTa2O9 with negative temperature coefficient of resonant frequency (τ f ) were selected as candidates for compensating the τ f of hexagonal perovskite Ba8ZnTa6O24. X-ray diffraction data shows that Ba8ZnTa6O24 coexists with Ba3NiTa2O9 but is not compatible with MgTiO3 and MgNb2O6 at high temperature. The τ f for the mixed hexagonal/cubic perovskite Ba8ZnTa6O24–Ba3NiTa2O9 system is tunable via the temperature compensation effect and its quality factor may be improved via annealing the ceramics at high temperature to enhance the cation ordering in the cubic component. Permittivity ε r ~ 22–25, Q×f > 30,000 GHz and tunable τ f within ±10 ppm/°C were achieved in the range of about 50–80 wt% Ba3NiTa2O9 for the hexagonal/cubic perovskite composite Ba8ZnTa6O24–Ba3NiTa2O9 ceramics, which is suitable for the application as dielectric resonators and filters. 相似文献
99.
为了符合某企业的轴向柱塞泵测试要求,对轴向变量柱塞泵的静态性能的测试方法进行了研究,并设计及开发了该测控系统。该测控系统利用虚拟仪器技术、计算机技术、传感器技术、可编程逻辑控制器技术、数据采集卡技术等多种现代科学技术,实现了机电液一体化的控制。测控系统的关键参数如压力、转速、控制信号的测试精度通过闭环控制得到保证。在建立测试信息数据库后,测控系统能对按测试工序模块化自动连续完成一系列试验的测试。现场测试表明,该测控系统能对多种规格的轴向柱塞的静态性能(排量验证、变量特性、效率特性、超载试验)进行自动测试,同时测试结果良好。 相似文献
100.
Daojin Zhou Zhao Cai Yongmin Bi Weiliang Tian Ma Luo Qian Zhang Qian Zhang Qixian Xie Jindi Wang Yaping Li Yun Kuang Xue Duan Michal Bajdich Samira Siahrostami Xiaoming Sun 《Nano Research》2018,11(3):1358-1368
Nickel-iron layered double hydroxide (NiFe-LDH) nanosheets have shown optimal oxygen evolution reaction (OER) performance; however, the role of the intercalated ions in the OER activity remains unclear. In this work, we show that the activity of the NiFe-LDHs can be tailored by the intercalated anions with different redox potentials. The intercalation of anions with low redox potential (high reducing ability), such as hypophosphites, leads to NiFe-LDHs with low OER overpotential of 240 mV and a small Tafel slope of 36.9 mV/dec, whereas NiFe-LDHs intercalated with anions of high redox potential (low reducing ability), such as fluorion, show a high overpotential of 370 mV and a Tafel slope of 80.8 mV/dec. The OER activity shows a surprising linear correlation with the standard redox potential. Density functional theory calculations and X-ray photoelectron spectroscopy analysis indicate that the intercalated anions alter the electronic structure of metal atoms which exposed at the surface. Anions with low standard redox potential and strong reducing ability transfer more electrons to the hydroxide layers. This increases the electron density of the surface metal sites and stabilizes their high-valence states, whose formation is known as the critical step prior to the OER process. 相似文献