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91.
设计了一种简化的铝栅MOS半导体器件制作工艺流程,用6张掩模版成功制作出了基于表面电场效应原理的生物检测硅芯片传感器,采用SiO2-Si3N4复合栅介质层及耗尽型器件结构,以增强器件的识别与检测灵敏度。该传感器与常规铝栅MOS晶体管相比,去除了介质层表面的栅极导电层,代之以自组装技术制作生物薄膜并辅以栅参考电极作为控制栅极。用所制作的硅芯片传感器检测了相关生物蛋白质的电流响应,给出了该电流响应与器件沟道长度和沟道电阻及生物蛋白浓度等参数的关系,得到了较为满意的检测数据,达到了预期的基于表面电场效应的硅传感器制作和生物检测的目的。 相似文献
92.
Jingjing Zhang Wei Wang Shijie You Dianpeng Qi Zhiyuan Liu Dongmei Liu Ming Ma Fuyi Cui Nanqi Ren Xiaodong Chen 《Advanced functional materials》2020,30(7)
Biological wastewater treatment (BWT), which is used to manage global wastewater, suffers from a sharp decrease in microbial activity at low temperature (<10 °C). Photothermal technology with a high energy efficiency theoretically exceeding 80% has the potential to activate low‐temperature BWT. However, photothermal BWT is threatened by the propagation of photosynthetic algae in wastewater under irradiation, and these microorganisms can suppress the functional bacteria or even kill anaerobic species by photosynthetically releasing oxygen. Herein, taking microbial fuel cells (MFCs) as a representative biological reactor, a photothermal Janus anode (PTJA) is designed, composed of a carbon black/polydimethylsiloxane photothermal nonporous layer and a graphite felt porous layer to promote low‐temperature BWT. Unlike traditional symmetrical porous anodes, the nonporous layer of the PTJA can isolate the wastewater in the porous layer from light irradiation during photothermal conversion, thus preventing photosynthetic algae from poisoning anaerobic functional microbes. Under ≈1 sun illumination, the PTJA MFC exhibits 1.6 and 24.2 times higher organic pollutant removal rate and power density generation, respectively, than MFCs using traditional anodes for low‐temperature BWT (7.0 ± 2.0 °C). This development can allow novel utilization of solar energy and is a promising resolution for low‐temperature BWT. 相似文献
93.
94.
方植彬 《电子产品可靠性与环境试验》2014,32(5):55-61
随着社会公共安全和个人的自身信息安全要求的提高,生物识别技术成为安全验证的首选方式,它是一种利用人体生物特征对人进行身份识别的高科技技术。简要地介绍了生物识别技术出现的背景、生物识别技术的概念、生物识别的基本过程和生物识别技术的发展动态,以及发展前景。对当前比较流行的几种生物识别技术指纹识别、虹膜识别、视网膜识别、人脸识别、签名识别和声音识别等,从原理及其特点上予以了论述和比较。 相似文献
95.
从植物生理学观点出发,用物理学方法讨论了He-Ne激光对生物细胞膜的渗透性影响。结果表明用He-Ne激光场辐照油松种子,有利于其细胞膜渗透能力的提高,并可产生有益的生物效应。 相似文献
96.
强电磁辐射、工频电场与磁场及紫外线辐射均可产生生物效应。详细讨论了电磁环境的生物学效应;计算了典
型通信基站同时考虑邻近扇区辐射影响实际安全防护距离随方位的变化特性,其天线最大辐射方向上和最小辐射方位上
的最小安全防护距离分别为35.43m 和18.16m;利用等效电荷法计算了220kV、330kV 和500kV 高压输电线下空间工频
电场强度分布和安全防护距离,相对应输电线下电场最小安全防护距离分别为距边线外3.1m、8.0m 和12.7m。 相似文献
97.
98.
Multifunctional Silver‐Exchanged Zeolite Micromotors for Catalytic Detoxification of Chemical and Biological Threats 下载免费PDF全文
Virendra V. Singh Beatriz Jurado‐Sánchez Sirilak Sattayasamitsathit Jahir Orozco Jinxing Li Michael Galarnyk Yuri Fedorak Joseph Wang 《Advanced functional materials》2015,25(14):2147-2155
Multifunctional reactive‐zeolite‐based micromotors have been developed and characterized toward effective and rapid elimination of chemical and biological threats. The incorporation of silver ions (Ag+) into aluminosilicate zeolite framework imparts several attractive functions, including strong binding to chemical warfare agents (CWA) followed by effective degradation, and enhanced antibacterial activity. The new zeolite‐micromotors protocol thus combines the remarkable adsorption capacity of zeolites and the efficient catalytic properties of the reactive Ag+ ions with the autonomous movement of the zeolite micromotors for an accelerated detoxification of CWA. Furthermore, the high antibacterial activity of Ag+ along with the rapid micromotor movement enhances the contact between bacteria and reactive Ag+, leading to a powerful “on‐the‐fly” bacteria killing capacity. These attractive adsorptive/catalytic features of the self‐propelled zeolite micromotors eliminate secondary environmental contamination compared to adsorptive micromotors. The distinct cubic geometry of the zeolite micromotors leads to enhanced bubble generation and faster movement, in unique movement trajectories, which increases the fluid convection and highly efficient detoxification of CWA and killing of bacteria. The attractive capabilities of these zeolite micromotors will pave the way for their diverse applications in defense, environmental and biomedical applications in more economical and sustainable manner. 相似文献
99.
PbS/CdS/ZnS Quantum Dots: A Multifunctional Platform for In Vivo Near‐Infrared Low‐Dose Fluorescence Imaging 下载免费PDF全文
Antonio Benayas Fuqiang Ren Elisa Carrasco Vicente Marzal Blanca del Rosal Belete A. Gonfa Ángeles Juarranz Francisco Sanz‐Rodríguez Daniel Jaque José García‐Solé Dongling Ma Fiorenzo Vetrone 《Advanced functional materials》2015,25(42):6650-6659
Over the past decade, near‐infrared (NIR)‐emitting nanoparticles have increasingly been investigated in biomedical research for use as fluorescent imaging probes. Here, high‐quality water‐dispersible core/shell/shell PbS/CdS/ZnS quantum dots (hereafter QDs) as NIR imaging probes fabricated through a rapid, cost‐effective microwave‐assisted cation exchange procedure are reported. These QDs have proven to be water dispersible, stable, and are expected to be nontoxic, resulting from the growth of an outer ZnS shell and the simultaneous surface functionalization with mercaptopropionic acid ligands. Care is taken to design the emission wavelength of the QDs probe lying within the second biological window (1000–1350 nm), which leads to higher penetration depths because of the low extinction coefficient of biological tissues in this spectral range. Furthermore, their intense fluorescence emission enables to follow the real‐time evolution of QD biodistribution among different organs of living mice, after low‐dose intravenous administration. In this paper, QD platform has proven to be capable (ex vivo and in vitro) of high‐resolution thermal sensing in the physiological temperature range. The investigation, together with the lack of noticeable toxicity from these PbS/CdS/ZnS QDs after preliminary studies, paves the way for their use as outstanding multifunctional probes both for in vitro and in vivo applications in biomedicine. 相似文献
100.