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Chonnipa Yeerum Piyanat Issarangkura Na Ayutthaya Kullapon Kesonkan Kanokwan Kiwfo Ploenpit Boochathum Kate Grudpan Monnapat Vongboot 《Molecules (Basel, Switzerland)》2022,27(7)
A new biodegradable platform-based sensor for formaldehyde assay is proposed. Natural rubber latex was modified to polylactic acid–chloroacetated natural rubber polymer blend sheets. The polymer blend sheet was grafted using a water-based system with amine monomers as a platform, with a spot exhibiting positive polarity for immobilizing with anionic dye (Acid Red 27). The sensor was exposed to formaldehyde. The color intensity of the dye on the sensor spot would decrease. Using a smartphone with image processing (via ImageJ program), the color intensity change (∆B) could be followed. A linear calibration, ∆B intensity = 0.365 [FA] + 6.988, R2 = 0.997, was obtained for 10–150 mM FA with LOD and LOQ at 3 and 10 mM, respectively (linear regression method). The precision was lower than 20% RSD. Application to real seafood samples was demonstrated. The ready-to-use sensor with the proposed method was cost-effective, was portable for on-site analysis, and demonstrated green chemical analysis. 相似文献
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远程物理实验控制平台的设计与开发 总被引:2,自引:0,他引:2
将网络远程控制技术运用于物理实验教学中,设计并开发出远程物理实验控制平台.该平台的建设能够有效地实现物理实验设备硬件资源共享,为各高校开展物理实验课程提供了全新的方法和途径. 相似文献
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The Lanzhou All Permanent magnet ECR ion source NO.1(LAPECR1)is the first all permanent magnet multiple ECRIS made in IMP.This ECRIS is running at 14.5GHz and can provide intense low charge state ion beams(varying from several to hundreds of eμA)or medium charge state ion beams(varying from several to tens of eμA).The size of source body is (?)102mm×296mm,the compactness and economical features enable the source suitable to be put on a HV platform or equipped by a small laboratory.This article gives the main parameters of the ion source. 相似文献
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A novel packet format with non-return-to-zero (NRZ) label and duobinary carrier-suppressed return-to-zero (DCS-RZ) payload is proposed for optical packet switching networks.NRZ label is followed by DCS-RZ payload with a certain guard time.The spectra of the low-rate NRZ label locate around the optical carrier frequency where some parts of the corresponding spectra of the high-rate DCS-RZ payload have been suppressed due to DCS-RZ modulation.At the switching node,the label or payload extraction can be realized simply through an optical bandpass or notch filter respectively.The feasibility of the scheme is verified by the simulation on the famous photonic design platform designed by Virtual Photonics Inc.(VPI).The effects of optical filter bandwidth on the received signal quality are discussed by analyzing bit error rate(BER)and contrast ratio performances. 相似文献
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为了与新型高精度惯性平台相匹配,解决传统PID控制的稳定回路抗干扰性能不高的问题,利用神经网络具有自学习、自组织、联想记忆和并行处理等功能以及对于复杂系统控制可以达到满意效果的优势,设计了单神经元自校正PID控制器。这种控制器不但结构简单,而且适应环境变化,有较强的鲁棒性。设计中分别采用了无监督和有监督的Hebb学习算法以及改进的Hebb学习算法对系统进行控制。MATLAB仿真结果表明,单神经元自校正PID控制器在很多指标上均优于传统PID控制器,特别是其超调量,动态性能以及对干扰的抑制能力,是一种应用在实际平台系统中理想的控制器。 相似文献
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Microgels absorb and retain high amounts of solvents, especially water. Because of their size, and association, the release kinetics of active molecules from microgels is easier to control than in hydrogels. Collagen I is one of the most extensively investigated biomaterials, although the key process parameters to produce microgels must be understood well before they can be used in veterinary and human medicine. Emulsification-gelation is widely used to obtain microgels because of its ease of handling and high yields. The concentration of the biomaterial and the homogenization method are among the critical parameters in this method. In this work, we produced cytocompatible collagen I microgels by emulsification-gelation and evaluated the effect of three different concentrations and homogenization methods on their physicochemical, mechanical, and biological properties. As proof of concept, microgels were loaded with an Aloe vera extract and the loading efficiency and the polyphenol release kinetics, as well as their properties assessed. When the same homogenization method (e.g. magnetic stirring) was used, the size of the microgels decreased with an increase of collagen I concentration, and the size distribution increased. In addition, the size and size distribution of microgels prepared with the same collagen I concentration were smaller when produced by high-energy homogenization methods (shear stress and ultrasound) than with a low-energy one (magnetic stirring). Collagen I concentration and the homogenization method also influenced the zeta-potential, the enzymatic degradation, and the encapsulation efficiency of the microgels. Overall, we show that the size of these microgels can be fine-tuned by the collagen I concentration and the homogenization method. Moreover, the integration of microgels of different sizes into the same carrier platform will pave the way for the combination of active compounds with different release kinetics. 相似文献