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Toward visual chiral recognition of amino acids using a wide-range color tonality ratiometric nanoprobe
, Article Analytica Chimica Acta ; Volume 1231 , 2022 ; 00032670 (ISSN) ; Fahimi Kashani, N ; Morad, R ; Jamshidi, Z ; Hormozi Nezhad, M. R ; Sharif University of Technology
Elsevier B.V
2022
Abstract
Chiral recognition has long been a challenging issue to deal with in biological systems, drug design and food authentication. Implementing nanoparticle-based probes with intrinsic or induced chirality in this field has addressed several issues concerning sensitivity, reliability, rapidness and the cost of chiral sensing platforms. Yet, research into chiral nanoprobes that can be used for visual monitoring of chiral substances is still in its infancy. As part of this study, a visual chiral recognition platform has been developed in which a combination of blue-emitting carbon dots (BCDs) and mercaptopropionic acid-capped CdTe quantum dots (MPA-QDs) with inherent chiroptical activity were...
Aggregation-Based Colorimetric Sensor for Determination of Prothioconazole Fungicide Using Colloidal Silver Nanoparticles (AgNPs)
, M.Sc. Thesis Sharif University of Technology ; Hormozi-Nezhad, Mohammad Reza (Supervisor)
Abstract
There is a growing interest in developing high-performance sensors monitoring fungicides, due to their broadly usage and their adverse effects on humans and wildlife. In the present study, a colorimetric probe has been proposed for detection of prothioconazole based on aggregation of unmodified silver nanoparticles (AgNPs). Under optimized condition, linear relationships between the concentration of prothioconazole and the absorbance ratio of A500/A395 were found over the range of 0.01 µg. mL-1 to 0.4 µg. mL-1 with Detection limit as low as 1.7 ng. mL-1. Furthermore, AgNPs color change from yellow to pink-orange in presence of prothioconazole, indicates highly sensitive naked-eye...
Visual recognition of tryptophan enantiomers using chiral self assemblies of quantum dots
, Article ACS Applied Nano Materials ; 2021 ; 25740970 (ISSN) ; Jafar Nezhad Ivrigh, Z ; Bigdeli, A ; Hormozi Nezhad, M.R ; Sharif University of Technology
American Chemical Society
2021
Abstract
Discrimination of chiral targets is generally achieved with chiral nanomaterials. However, the limited number of intrinsic chiral nanostructures as well as their complex synthesis procedure has led to the production of chirality-induced nanomaterials as alternatives. Chirality can be induced in nanomaterials by either chirality transfer or the formation of chiral assemblies. Using the latter approach, in this work, we have provided chiral supramolecular assemblies of CdTe quantum dots (QDs) from achiral starting materials. CTAB-QD assemblies showed chiroptical activities, and their orange emission in combination with the blue emission of carbon dots was utilized as a ratiometric chiral...
Optical nanoprobes for chiral discrimination
, Article Analyst ; Volume 145, Issue 20 , 2020 , Pages 6416-6434 ; Ghasemi, F ; Fahimi Kashani, N ; Abbasi Moayed, S ; Orouji, A ; Jafar Nezhad Ivrigh, Z ; Shahdost Fard, F ; Hormozi Nezhad, M. R ; Sharif University of Technology
Royal Society of Chemistry
2020
Abstract
Chiral discrimination has always been a hot topic in chemical, food and pharmaceutical industries, especially when dealing with chiral drugs. Enantiomeric recognition not only leads to better understanding of the mechanism of molecular recognition in biological systems, but may further assist in developing useful molecular devices in biochemical and pharmaceutical studies. By emerging nanotechnology and exploiting nanomaterials in sensing applications, a great deal of attention has been given to the design of optical nanoprobes that are able to discriminate enantiomers of chiral analytes. This review explains how engineering nanoparticles (NPs) with desired physicochemical properties allows...
Visual recognition of tryptophan enantiomers using chiral self assemblies of quantum DOTS
, Article ACS Applied Nano Materials ; Volume 5, Issue 1 , 2022 , Pages 1460-1471 ; 25740970 (ISSN) ; Jafar Nezhad Ivrigh, Z ; Bigdeli, A ; Hormozi Nezhad, M. R ; Sharif University of Technology
American Chemical Society
2022
Abstract
Discrimination of chiral targets is generally achieved with chiral nanomaterials. However, the limited number of intrinsic chiral nanostructures as well as their complex synthesis procedure has led to the production of chirality-induced nanomaterials as alternatives. Chirality can be induced in nanomaterials by either chirality transfer or the formation of chiral assemblies. Using the latter approach, in this work, we have provided chiral supramolecular assemblies of CdTe quantum dots (QDs) from achiral starting materials. CTAB-QD assemblies showed chiroptical activities, and their orange emission in combination with the blue emission of carbon dots was utilized as a ratiometric chiral...
Aggregation-based colorimetric sensor for determination of prothioconazole fungicide using colloidal silver nanoparticles (AgNPs)
, Article Spectrochimica Acta - Part A: Molecular and Biomolecular Spectroscopy ; Volume 187 , 2017 , Pages 143-148 ; 13861425 (ISSN) ; Fahimi Kashani, N ; Hormozi Nezhad, M. R ; Sharif University of Technology
2017
Abstract
There is a growing interest in developing high-performance sensors monitoring fungicides, due to their broadly usage and their adverse effects on humans and wildlife. In the present study, a colorimetric probe has been proposed for detection of prothioconazole based on aggregation of unmodified silver nanoparticles (AgNPs). Under optimized condition, linear relationships between the concentration of prothioconazole and the absorbance ratio of A500/A395 were found over the range of 0.01 μg·mL− 1 to 0.4 μg·mL− 1 with quantification limit as low as 1.7 ng·mL− 1. Furthermore, AgNPs color change from yellow to pink-orange in presence of prothioconazole, indicates highly sensitive naked-eye...
Multiplex detection of antidepressants with a single component condition-based colorimetric sensor array
, Article Sensors and Actuators B: Chemical ; Volume 363 , 2022 ; 09254005 (ISSN) ; Bigdeli, A ; Jafarinejad, S ; Hormozi Nezhad, M. R ; Sharif University of Technology
Elsevier B.V
2022
Abstract
Pattern-based sensing with multi-component sensor arrays, despite its merits, may be laborious and time-consuming. As an alternative approach, herein, a condition-based single component sensor array has been provided which represents an elegantly simple, low cost and minimally instrumented format for the quantification and classification of antidepressants (ADs). Tuning the pH and ionic strength enabled the single component probe to interact with the target analytes through different binding modes, providing the required cross-reactivity for multiplex detection. The analytical figures of merit verified that the condition-based sensor array is precise and accurate in both the discrimination...
Array-based sensing using gold and silver nanoparticles
, Article Gold and Silver Nanoparticles: Synthesis and Applications ; 2023 , Pages 165-204 ; 978-032399454-5 (ISBN) ; Abbasi Moayed, S ; Ivrigh, Z. J. N ; Hormozinezhad, M. R ; Sharif University of Technology
Elsevier
2023
Abstract
The array sensing mimics the mammalian gustatory/olfactory principle in which all responses collected from nonspecific receptors (i.e., cross-reactive or semi-selective recognition elements) represent a fingerprint-like pattern for each test/odor. Generally, three steps must be taken to develop a sensor array: (1) selection and design of sensor elements (recognition elements) which is the key step in sensor array design. (2) Selection of a data acquisition method to record signals from the interaction of sensor elements with the analytes. (3) Selection of a method/a few methods to analyze the collected multivariate data, illustrate the discrimination among analytes, and identify the unknown...
Erratum: A new ir-uwb pulse for the compatibility of IEEE802.11.a wlan and ir-uwb systems
, Article Journal of Circuits, Systems and Computers ; Vol. 23, issue. 5 , 2014 ; Fotowat-Ahmady, A ; Nezhad, A. Z ; Sharif University of Technology
2014
Abstract
[No abstract available]
A 90 nm-CMOS IR-UWB BPSK transmitter with spectrum tunability to improve peaceful UWB-narrowband coexistence
, Article IEEE Transactions on Circuits and Systems I: Regular Papers ; Vol. 61, issue. 6 , January , 2014 , p. 1836-1848 ; 15498328 ; Fotowat-Ahmady, A ; Nezhad, A. Z ; Serdijn, W. A ; Sharif University of Technology
2014
Abstract
A new ultra wideband (UWB) pulse generator covering a-10 dB bandwidth of 2.4-4.6 GHz with a tunable center frequency of 5-5.6 GHz to mitigate coexistence issues of impulse radio UWB (IR-UWB) systems and IEEE802.11.a WLAN or other narrowband (NB) systems in 90 nm-CMOS technology is proposed. The UWB pulse is generated based on frequency up-conversion of the first derivative of the Gaussian pulse, which creates an adjustable null in the frequency spectrum. Simulation results show that employing the proposed pulse generator mitigates the mutual interference between UWB and WLAN systems, significantly. The proposed transmitter consists of a low frequency signal generator, an LC oscillator and a...
Design of Optical Sensor Arrays Using Plasmonic and Fluorescent Nanoprobes for the Detection of Antidepressants, Biothiols, and Discrimination of the Enantiomers of Tryptophan, Histidine, and Arginine
, Ph.D. Dissertation Sharif University of Technology ; Hormozinezhad, Mohammad Reza (Supervisor)
Abstract
In the first part of this research, a single-component colorimetric sensor array based on the aggregation of AuNPs has been designed for the quantification and classification of antidepressant drugs (fluvoxamine (Flu), nortriptyline (Nor), citalopram (Cit), alprazolam (Alp), diazpam (Dia), sertraline (Ser), zolpidem (Zol), and imipramine (Imi)). Tuning the pH and ionic strength enabled the single-component probe to interact with the target analytes through different binding modes, providing the required cross-reactivity. To generate the array, a single AuNP was embedded into six experimental conditions: three different buffers (acidic, neutral and basic) each at two concentration levels (1mM...
Chlorophyll-based wicking sensing bioplatform coupled with a smartphone-based sample-to-answer analytical device for on-site detection of picric acid
, Article Biosensors and Bioelectronics: X ; Volume 11 , 2022 ; 25901370 (ISSN) ; Abbasi Moayed, S ; Hamzei, Z ; Keshavarz, A ; Yousefi, S ; Hormozi Nezhad, M. R ; Golmohammadi, H ; Sharif University of Technology
Elsevier Ltd
2022
Abstract
The development of inexpensive, equipment-free, portable, and user/environmentally-friendly analytical devices that can be efficiently utilized for on-site detection of PA is still a great challenge. To address these unmet demands, we have developed a smartphone-based disposable sensing bioplatform through immobilization of chlorophyll in a cotton thread for fluorescent monitoring of picric acid (PA). The fluorescence quenching of chlorophyll upon increasing the PA concentration based on the inner filter effect was considered as the sensing strategy in the developed sensor. The fabricated thread-based microfluidic sensing bioplatform was further coupled with a compact, low cost, portable,...
Exploiting Locality Properties of Nodes for Improving Search Efficiency in P2P Networks
, M.Sc. Thesis Sharif University of Technology ; Habibi, Jafar (Supervisor)
Abstract
The Use of peer-to-peer architectures instead of traditional client-server architecture can be beneficial in many aspects such as increasing scalability of the systems, enhancing fault tolerance in critical situations, extending the system resources and various other advantages. Nowadays, many applications are based on peer-to-peer architectures and as a result, a large portion of the internet traffic is produced by these applications. This has been a motivation to many researchers to focus on reducing the amount of this traffic while satisfying the content distribution demands. One of the main problems that can result in generating large amount of traffic and also long response times for...
Automatic Extraction of Semantic Web Service Composition Patterns
, M.Sc. Thesis Sharif University of Technology ; Habibi, Jafar (Supervisor)
Abstract
In today’s competitive world، web services have become more and more prevalent and their efficient discovery and composition in order to create novel functionalities is essential for variety of applications. Due to the large number of available services، the discovery of services is a difficult and time consuming task. Existing approaches in web services discovery and composition attempt to use simple web services while ignoring the use of once composed services. Reusing frequently used composite services can considerably increase performance of the entire system. Moreover، the advent of semantic web، as an effective solution of representing information interpretable by machines and none...
An Engineering Approach to Software Modeling Language Development
, Ph.D. Dissertation Sharif University of Technology ; Habibi, Jafar (Supervisor)
Abstract
Nowadays, the essentiality of appropriate modeling languages has become evident, and with the introduction of new concepts such as domain-specific languages, the need for systematic research on designing and engineering new modeling languages has increased significantly. Several modeling languages have been developed and employed over the years, but the area of modeling languages still suffers from the lack of a proper framework: There is a strong need for an engineering framework that specifies the detailed steps of language development, the input and output artifacts of each step, the techniques applicable to each step, and quantifiable methods for quality measurement. From a unified point...
Distributed Data Mining in Peer-to-Peer Systems
, Ph.D. Dissertation Sharif University of Technology ; Habibi, Jafar (Supervisor)
Abstract
Peer-to-peer (P2P) computing is a popular distributed computing paradigm for many applications which in-volve exchange of information among a large number of peers. In such applications, large amount of data is distributed among multiple dispersed sources. Therefore, data analysis is challenging due to processing, storage and transmission costs. Moreover, the data rarely remains static and frequent data changes, quickly out date previously extracted data mining models. Distributed data mining deals with the problem of data analysis in environments with distributed data and computing resources. In this dissertation, we explore distributed data mining in different structures of P2P systems. In...
An Architecture Description Language for Software Product Line
, M.Sc. Thesis Sharif University of Technology ; Habibi, Jafar (Supervisor)
Abstract
Software Product Line is known as a process of developing family of the software together. The methods of building a software product line is trying to capture commonality and variety of this family of software and form a product line based on them. Commonality of this family of the software allows us reuse in every aspect of the development of software. Nowadays, software architecture as a one of the most important aspect of software engineering, plays major role in specifying the tasks and clearing the relationship between people. It can divide large and complex system to some sub-system and overcome complexity of the system. Software architecture forms a basis for communication among...
Designing a Model-Based Process and Architecture for Partial Automation of Software Development
, M.Sc. Thesis Sharif University of Technology ; Habibi, Jafar (Supervisor)
Abstract
Automation of the software development process is the software engineers' final goal, but with the current facilities and knowledge in software engineering, it is not possible to automatically generate the whole software. Usually all the software in a specific domain contain common behaviors, which by careful exploration of these common behaviors and automation of code generation in these sections, the cost and time of projects' execution can be reduced. According to Model Driven Development (MDD), the first step in software development is creating appropriate models. For creating models, metamodel is required; therefore, we need to create a specific motamodel for the chosen domain or use...
Towards a Mechanism to Design Software Product Line Architecture Based on Heterogeneous Styles
, M.Sc. Thesis Sharif University of Technology ; Habibi, Jafar (Supervisor)
Abstract
One of approaches in software architecture design is using architecture styles or patterns. This approach is a suitable way for satisfying functional and nonfunctional requirements and also is cost effective. It is shown that this approach improves effectively quality of software systems. Whereas, choosing a suitability architecture style for complex designs depends on many factors and often one style cannot meet all the requirements, therefore, use of heterogeneous styles can be useful. Also, in software product line architecture design, we must combine different kinds of architectural styles to cover the problem domain and achieve better performance. Correct and accurate choice of...
Model Selection for Complex Network Generation
, M.Sc. Thesis Sharif University of Technology ; Habibi, Jafar (Supervisor)
Abstract
Nowadays, there exist many real networks with distinctive features in comparison with random networks. Social networks, collaboration networks, citation networks, protein networks and communication networks are some example of complex network classes. Nowadays these networks are widespread and have many applications and the study of complex networks is an important research area. In many applications, the “synthetic networks generation” is one of the first levels of complex networks analysis. This level has many applications such as simulation and extrapolation. Many generative models are proposed for complex network modeling in recent years. By the use of these models, synthetic networks...