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排序方式： 共有1894条查询结果，搜索用时 15 毫秒
91.
Razieh Salahandish Hossein Zargartalebi Mohsen Janmaleki Sultan Khetani Milad Azarmanesh Mehdi Mohammadi Ashani Raied Aburashed Maryam Vatani Ali Ghaffarinejad Amir Sanati‐Nezhad 《Advanced Materials Technologies》2019,4(11)
Electrochemical nanobiosensors are ultrasensitive tools used for detection and monitoring of various markers in biofluids. In the absence of reliable techniques for large‐scale production of reproducible nanomaterial structures on the electrodes, they are created individually in batch‐production. This has become a substantial hurdle in the practical implementation of electrochemical nanobiosensors. An automated microfluidic‐based platform (NanoChip) is presented for reproducible and scalable formation of complex nanomaterial constructs with a defined order of nanocomposites and biomaterials to create ultrasensitive nanobiosensors. The automated liquid handling system of the setup delivers reagents to electrodes inserted temporarily into the chip for modifying their surfaces by depositing different nanomaterials. The NanoChip platform is used for the creation of a multilayer nanocomposite structure on the electrode surface. These reproducible nanobiosensors are used for detecting breast cancer cells in the blood. The nanobiosensors offered a dynamic detection range of 10 to 5 × 106 cells mL−1. Performance of sensors produced from NanoChip shows similar selectivity and operational range along with improved sensitivity and reproducibility compared to sensors developed using batch process. These features make automated Nanochip technology a versatile tool for producing nanosensors for the ultrasensitive detection of various markers in biomedical, clinical, energy, and environmental applications. 相似文献
92.
This paper investigates the robust stability analysis of fractional‐order interval systems with multiple time delays, including retarded and neutral systems. A bound on the poles of fractional‐order interval systems of retarded and neutral type is obtained. Then, the concept of the value set and zero exclusion principle is extended to these systems, and a necessary and sufficient condition is produced for checking the robust stability of them. The value set of the characteristic equation of the systems is obtained analytically and, based on it, an auxiliary function is introduced to check the zero exclusion principle. Finally, two numerical examples are given to illustrate the effectiveness of the results presented. 相似文献
93.
An important challenge in radio frequency identification (RFID) systems is the collision concern. When an interrogator send a request, it has several tags to answer to in its transmission range, and a tag collision has occurred. The interrogator must be able to recognize tags as rapidly as possible. A collision problem is a power‐consuming occurrence that diminishes the operation of RFID structure. This article proposes a tag anti‐collision power‐clustering RFID algorithm for all tag identification. The tags are boundaries into the several power level clusters based on distances of the reader. Specifically, in the proposed algorithm, tags and readers use of balanced incomplete blocks design (BIBD) to reach a fast identification. In a BIBD matrix, any two columns intersect exactly in one component that makes it possible for easy transmission of any two tags via the tag's identification in their read cycles. The aim of this article is to propose a joint organization that while decreases power consumption increases the working lifetime of RFID structure. The reader can get each tag ID by distinguishing each unit of BIBD symbols, one by one. The use of proposed algorithm brings about a great improvement in the power consumption and identification time. 相似文献
94.
Cloud computing has become a potential resource for businesses and individuals to outsource their data to remote but highly accessible servers. However, the potential of cloud services has not been fully realized due to users concerns about data privacy and security. User‐side encryption techniques can be employed to mitigate the security concerns, but once the data is encrypted, no processing (eg, searching) can be performed on the outsourced data. Searchable Encryption (SE) techniques have been widely studied to enable searching on the data while they are encrypted. These techniques enable various types of search on the encrypted data and offer different levels of security. While these techniques enable different search types and vary in details, they share similarities in their components and architectures. In this paper, we provide a comprehensive survey on different secure search techniques, a high‐level architecture for these systems, and an analysis of their performance and security level. 相似文献
95.
Sana Pirmardvand Chegini Jaleh Varshosaz Hamid Mirmohammad Sadeghi Alireza Dehghani Mohsen Minayian 《IET nanobiotechnology / IET》2019,13(9):974
Poly(glycerol sebacate) (PGS) is a new biodegradable polymer with good biocompatibility used in many fields of biomedicine and drug delivery. Sunitinib‐loaded PGS/gelatine nanoparticles were prepared by the de‐solvation method for retinal delivery and treatment of diabetic retinopathy. The nanoparticles were characterised by Fourier‐transform infrared and differential scanning calorimetry. The effects of different formulation variables including drug‐to‐carrier ratio, gelatine‐to‐PGS ratio, and glycerine‐to‐sebacate ratio were assessed on the encapsulation efficiency (EE%), particle size, release efficiency (RE), and zeta potential of the nanoparticles. The in vitro cytotoxicity of PGS/gelatine nanoparticles was studied on L929 cells. Draize test on rabbit eyes was also done to investigate the possible allergic reactions caused by the polymer. Glycerine/sebacic acid was the most effective parameter on the EE and RE. Gelatine‐to‐PGS ratio had the most considerable effect on the particle size while the RE was more affected by the glycerine/sebacic acid ratio. The optimised formulation (S1 G0.7 D21.2) exhibited a particle size of 282 nm, 34.6% EE, zeta potential of −8.9 mV, and RE% of about 27.3% for drug over 228 h. The 3‐(4,5‐dimethylthuazol‐2‐yl)‐2,5‐diphenyltetrazolium bromide assay indicated PGS/gelatine nanoparticles were not cytotoxic and sunitinib‐loaded nanoparticles were not toxic at concentrations <36 nM.Inspec keywords: polymers, differential scanning calorimetry, toxicology, drug delivery systems, solvation, eye, encapsulation, particle size, drugs, biodegradable materials, nanofabrication, nanomedicine, nanoparticles, gelatin, Fourier transform infrared spectraOther keywords: gelatine‐to‐PGS ratio, glycerine‐to‐sebacate ratio, particle size, zeta potential, sunitinib‐loaded nanoparticles, biodegradable polymer, retinal delivery, differential scanning calorimetry, drug‐to‐carrier ratio, allergic reactions, physicochemistry, cytotoxicity, poly(glycerol sebacate) nanoparticles, sunitinib ocular delivery, drug delivery, sunitinib‐loaded PGS‐gelatine nanoparticles, Fourier‐transform, in vitro cytotoxicity, biocompatibility, Draize test, rabbit eyes, 3‐(4,5‐dimethylthuazol‐2‐yl)‐2,5‐diphenyltetrazolium bromide assay 相似文献
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97.
为了同时考虑沥青混合料在降温过程中温度应力的累积和松弛作用,确定临界开裂温度,对试件进行了线收缩系数试验,并利用间接拉伸试验确定其抗拉强度和蠕变柔量,由蠕变柔量和松弛模量的关系得到松弛模量的Prony系列表达式;由Boltzmann叠加原理,得到温度应力公式,计算出不同降温速率下产生的温度应力,根据低温抗拉强度曲线,确定出沥青混合料的临界开裂温度,并对结果予以验证。结果表明:该方法考虑了应力累积和松弛二者的综合作用,能够较好地反映沥青混合料的低温开裂特性,其计算结果与约束试件温度应力试验结果相近;该方法不仅适用于恒定降温速率,还适用于现场连续变速降温工况;随温度的降低或降温速率的增加沥青混合料内部温度应力累积速度加快,临界开裂温度随降温速率增加而升高。 相似文献
98.
Rezvani Mohsen Rajaratnam David Ignjatovic Aleksandar Pagnucco Maurice Jha Sanjay 《International Journal of Information Security》2019,18(4):465-479
International Journal of Information Security - With the tremendous growth of Web applications and services, eXtensible Access Control Markup Language (XACML) has been broadly adopted to specify... 相似文献
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100.