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981.
Mubashir Hussain Zhen Chen Mu Lv Jingyi Xu Xiaohan Dong Jingzhou Zhao Song Li Yan Deng Nongyue He Zhiyang Li Bin Liu 《中国化学快报》2021,31(12):3163-3167
The rapid identification of pathogens is crucial in controlling the food quality and safety. The proposed system for the rapid and label-free identification of pathogens is based on the principle of laser scattering from the bacterial microbes. The clinical prototype consists of three parts: the laser beam, photodetectors, and the data acquisition system. The bacterial testing sample was mixed with 10 mL distilled water and placed inside the machine chamber. When the bacterial microbes pass by the laser beam, the scattering of light occurs due to variation in size, shape, and morphology. Due to this reason, different types of pathogens show their unique light scattering patterns. The photo-detectors were arranged at the surroundings of the sample at different angles to collect the scattered light. The photodetectors convert the scattered light intensity into a voltage waveform. The waveform features were acquired by using the power spectral characteristics, and the dimensionality of extracted features was reduced by applying minimal-redundancy-maximal-relevance criterion (mRMR). A support vector machine (SVM) classifier was developed by training the selected power spectral features for the classification of three different bacterial microbes. The resulting average identification accuracies of E. faecalis,E. coli and S. aureus were 99%, 87%, and 94%, respectively. The overall experimental results yield a higher accuracy of 93.6%, indicating that the proposed device has the potential for label-free identification of pathogens with simplicity, rapidity, and cost-effectiveness. 相似文献
982.
Yupeng Xing Xiaoke Wang Shuhua Hao Xueli Zhang Xiao Wang Wenxuan Ma Gang Zhao Xijin Xu 《中国化学快报》2021,32(1):13-20
g-C3N4 have been widely used in the fields of photocatalytic hydrogen production,photocatalytic degradation of dyes and oxidative degradation of toxic gases due to their excellent performance.It has attracted extensive attention in recent years due to its highly efficient photocatalytic capacity of hydrogen generation,water oxidation,carbon dioxide reduction and degradation of organic pollutants.Because of the abundant carbon and nitrogen composition of the earth,large-scale production and industrial applications of this material are possible.The modification of this material makes its performance more excellent so that this new material can obtain a steady stream of vitality.These outstanding works have become important materials and milestones on the road to mankind's photocatalytic hydrogen production.This review will begin with the basic idea of designing,synthesizing and improving g-C3N4 based photocatalytic materials,and introduce the latest development of g-C3N4 photocatalysts in hydrogen production from four aspects of controlling the carbon/nitrogen ratio,morphology,element doping and heterojunction structure of g-C3N4 materials. 相似文献
983.
Yu Zhang Weimeng Chi Baiqing Zhang Zhuoxun Yin Xinzhi Ma Yang Zhou Wei Chen Lingling Xu Jinlong Li 《欧洲无机化学杂志》2023,26(34):e202300492
The conventional electrolytic water-splitting process for hydrogen production is plagued by high energy consumption, low efficiency, and the requirement of expensive catalysts. Therefore, finding effective, affordable, and stable catalysts to drive this reaction is urgently needed. We report a nanosheet catalyst composed of carbon nanotubes encapsulated with MoC/Mo2C, the Ni@MoC-700 nanosheet showcases low overpotentials of 275 mV for the oxygen evolution reaction and 173 mV for the hydrogen evolution reaction at a current density of 10 mA ⋅ cm−2. Particularly noteworthy is its outstanding performance in a two-electrode system, where a cell potential of merely 1.64 V is sufficient to achieve the desired current density of 10 mA ⋅ cm−2. Furthermore, the catalyst demonstrates exceptional durability, maintaining its activity over a continuous operation of 40 hours with only minimal attenuation in overpotential. These outstanding activity levels and long-term stability unequivocally highlight the promising potential of the Ni@MoC-700 catalyst for large-scale water-splitting applications. 相似文献
984.
The design of pore structure is the key factor for the performance of porous carbon spheres.In this wo rk,novel micron-sized colloidal crystal microspheres consisting of fibrous silica(F-SiO_2) nanoparticles are firstly prepared by water-evapo ration-induced self-assembly of F-SiO_2 nanoparticles in the droplets of an inverse emulsion system to be used as sacrificial templates.Acrylonitrile(AN) was infiltrated in the voids of the F-SiO_2 colloidal crystal microspheres,and in-situ induced by ~(60)Co y-ray to polymerize into polyacrylonitrile(PAN).After the PAN-infiltrated F-SiO_2 colloidal crystal microspheres were carbonized and etched with HF solution,novel micron-sized inverse-opal N-doped carbon(IO-NC) microspheres consisting of hollow carbon nanoparticles with a hierarchical macro/meso-porous inner surface were obtained.The IO-NC microspheres have a specific surface area as high as 266.4 m~2/g and a molar ratio of C/N of 5.They have a good dispersibility in water,and show a high adsorption capacity towards rhodamine B(RhB) up to 137.28 mg/(g microsphe re).This work offers a way to obtain novel micron-sized hierarchical macro/meso-porous N-doped carbon microspheres,which opens a new idea to prepare high-performance hierarchical porous carbon materials. 相似文献
985.
Shan Jiang Lingchen Meng Wenyue Ma Qingkai Qi Wei Zhang Bin Xu Leijing Liu Wenjing Tian 《中国化学快报》2021,32(3):1037-1040
Luminescent conjugated network polymer is one of the most promising chemo-sensors owing to their good chemical/optical stability and multiple functionalization.Herein,three conjugated network polymers were prepared by using aggregation-induced emission active 1,1,2,2-tetrakis(4-formyl-(1,1'-biphenyl))-ethane(TFBE) unit as monomer and hydrazine as linker.Through regulating the synthetical condition,the polyme ric network can form either unifo rm two-dimensional azine-linked nanosheets(ANS),conjugated microporous polymers(A-CMP) or covalent organic frameworks(A-COF).All of these polymers exhibited good stability and high fluorescence quantum efficiency with the quantum yield of6.31% for A-NS,5.26% for A-CMP,and 5.80% for A-COF,as well as fast and selective fluorescence quenching response to 2,4,6-trinitrophenol(TNP).And the best TNP sensing performance with the Stern-Volmer constants(K_(sv)) values up to 8 × 10~5 L/mol and a detection limit of 0.09 μmol/L was obtained for A-NS.The study explores various strategies to construct conjugated polymers with different nanoarchitectures based on the same building block for sensitive detection of explosives. 相似文献
986.
铈、锂盐对铝阳极氧化膜的协同封闭作用 总被引:11,自引:0,他引:11
研究了铈、锂盐在铝阳极氧化膜封闭处理中的协同作用.场发射扫描电镜和X射线衍射谱对铈、锂盐协同封闭前后铝阳极氧化膜形貌和结构的研究结果表明,封闭后膜表面的孔洞消失,封闭产物分布均匀,封闭后膜仍然以非晶态形式存在.根据X射线光电子能谱的结果,封闭后的膜主要由含结晶水的Al2O3及铈、锂的混合氢氧化物组成,同时膜中还含有及封闭溶液组分中的一些阴离子.电化学阻抗谱的研究结果表明铈、锂盐协同封闭能够显著提高膜的耐蚀性能.在实验结果基础上,初步认为铈、锂盐封闭是通过生成结构紧密的封闭产物填充、覆盖膜孔,从而显著提高铝阳极氧化膜的耐蚀性能. 相似文献
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