A Review on the Traditional Methods and Novel Techniques for Detection of Formaldehyde Concentration in Fish

International Journal for Research in Engineering Application & Management ◽

10.35291/2454-9150.2020.0299 ◽

2020 ◽

pp. 286-290

Keyword(s):

High Performance ◽

Food Preservation ◽

Formaldehyde Concentration ◽

The Novel ◽

Chemical Methods ◽

Traditional Methods ◽

Fish Quality ◽

Practical Applications ◽

Novel Technologies ◽

Non Destructive

Fish is an inevitable part of Kerala’s food style and around 3% of the State’s economy is attributed to Fisheries. The recent news that hit the headlines of Kerala was the seizing of formalin laced fish from many parts of Kerala. There are numerous conventional chemical methods for detecting formalin concentration in fish. The main drawback is that the majority of these techniques are time-consuming, tedious and destructive that requires welltrained operators and cannot be applied for on-field detection. In this current paper, the hazardous effects of formalin in human body, traditional methods used at present and the recently developed novel techniques for effective detection of formaldehyde concentration in fish, are analyzed. An overview of the conventional methods- chemical methods and microbial attributes are discussed. The novel techniques include high performance liquid chromatography (HPLC), electrochemical biosensors, catalytic kinetic flurimetry technique, fluorescence spectroscopy, photonic crystal fiber based sensor, enhanced Raman spectroscopy (SERS) technique and optical fiber bundle sensor. Also, the advantages of these techniques over traditional methods are pointed out. The novel techniques exhibit good linearity, stability, sensitivity, non-invasive, non-destructive and most of them have the potential to be developed as a portable device. Using this non-destructive technique, unethical means of food preservation can be monitored, thereby ensuring fish quality in Kerala. Even though there has been great advancement in this field, traditional methods are still dominant in practical applications. It is high time that new techniques find their way out, because the quality of fish consumed by the people of this State is decreasing by a quick rate. Therefore, further efforts are necessary to facilitate early adoption of novel technologies in the fish industry and promote their standardization to complement or replace current legislation standards for the evaluation of fish quality.

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Design and Fabrication of a Novel MEMS Relay with Low Actuation Voltage

Micromachines ◽

10.3390/mi11020171 ◽

2020 ◽

Vol 11 (2) ◽

pp. 171 ◽

Cited By ~ 2

Author(s):

Hao Li ◽

Yong Ruan ◽

Zheng You ◽

Zhiqiang Song

Keyword(s):

Contact Resistance ◽

High Performance ◽

Actuation Voltage ◽

Micro Electro Mechanical System ◽

Anodic Bonding ◽

The Novel ◽

Restoring Force ◽

Widespread Application ◽

Practical Applications ◽

Contact Electrode

Compared with conventional solid-state relays, micro-electro mechanical system (MEMS) relays have the advantages of high isolation, low contact resistance, low power consumption, and abrupt switching characteristics. Nevertheless, the widespread application of MEMS relays has been limited due to the issue of the conflict between low actuation voltages and high device performance. This article presents a novel cantilever MEMS relay with an embedded contact electrode which helps to achieve a low actuation voltage (below 8 V) and high restoring force simultaneously. Meanwhile, the contact resistance is as low as around 0.4 Ω and the reliability is verified. To thoroughly investigate and analyze the novel cantilever MEMS relay, a static theoretical model of the structure was developed. Based on the model, the cantilever MEMS relay was designed and optimized. Then, the relays were fabricated by the bulk-silicon micromachining process based on the silicon–glass anodic bonding technology. Finally, the switching performance of the novel cantilever MEMS relay was measured. Experimental results demonstrate that the proposed MEMS relay has a low actuation voltage below 8 V and high performance, which is in good agreement with the simulation results, and shows significant advantages when compared with previous reports. Therefore, the proposed MEMS relay with an embedded contact electrode is promising in practical applications.

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Flux Method Growth of Large Size Group IV–V 2D GeP Single Crystals and Photoresponse Application

Crystals ◽

10.3390/cryst11030235 ◽

2021 ◽

Vol 11 (3) ◽

pp. 235

Author(s):

Shuqi Zhao ◽

Tongtong Yu ◽

Ziming Wang ◽

Shilei Wang ◽

Limei Wei ◽

...

Keyword(s):

Raman Spectroscopy ◽

Single Crystals ◽

High Performance ◽

Group Iv ◽

X Ray Diffraction ◽

High Quality ◽

Practical Applications ◽

Large Size ◽

Growth Method ◽

Polarized Raman

Two-dimensional (2D) materials driven by their unique electronic and optoelectronic properties have opened up possibilities for their various applications. The large and high-quality single crystals are essential to fabricate high-performance 2D devices for practical applications. Herein, IV-V 2D GeP single crystals with high-quality and large size of 20 × 15 × 5 mm3 were successfully grown by the Bi flux growth method. The crystalline quality of GeP was confirmed by high-resolution X-ray diffraction (HRXRD), Laue diffraction, electron probe microanalysis (EPMA) and Raman spectroscopy. Additionally, intrinsic anisotropic optical properties were investigated by angle-resolved polarized Raman spectroscopy (ARPRS) and transmission spectra in detail. Furthermore, we fabricated high-performance photodetectors based on GeP, presenting a relatively large photocurrent over 3 mA. More generally, our results will significantly contribute the GeP crystal to the wide optoelectronic applications.

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Pocket MUSE: an affordable, versatile and high-performance fluorescence microscope using a smartphone

Communications Biology ◽

10.1038/s42003-021-01860-5 ◽

2021 ◽

Vol 4 (1) ◽

Author(s):

Yehe Liu ◽

Andrew M. Rollins ◽

Richard M. Levenson ◽

Farzad Fereidouni ◽

Michael W. Jenkins

Keyword(s):

High Performance ◽

Point Of Care ◽

Low Cost ◽

Consumer Electronics ◽

Practical Implementation ◽

The Novel ◽

Point Of Care Diagnostics ◽

Optical Module ◽

Optical Configuration ◽

User Friendly

AbstractSmartphone microscopes can be useful tools for a broad range of imaging applications. This manuscript demonstrates the first practical implementation of Microscopy with Ultraviolet Surface Excitation (MUSE) in a compact smartphone microscope called Pocket MUSE, resulting in a remarkably effective design. Fabricated with parts from consumer electronics that are readily available at low cost, the small optical module attaches directly over the rear lens in a smartphone. It enables high-quality multichannel fluorescence microscopy with submicron resolution over a 10× equivalent field of view. In addition to the novel optical configuration, Pocket MUSE is compatible with a series of simple, portable, and user-friendly sample preparation strategies that can be directly implemented for various microscopy applications for point-of-care diagnostics, at-home health monitoring, plant biology, STEM education, environmental studies, etc.

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Hyperspectral Imaging for Bloodstain Identification

Sensors ◽

10.3390/s21093045 ◽

2021 ◽

Vol 21 (9) ◽

pp. 3045

Author(s):

Maheen Zulfiqar ◽

Muhammad Ahmad ◽

Ahmed Sohaib ◽

Manuel Mazzara ◽

Salvatore Distefano

Keyword(s):

Hyperspectral Imaging ◽

Dna Analysis ◽

Forensic Sciences ◽

Blood Protein ◽

Chemical Methods ◽

Acrylic Paint ◽

Spectral Bands ◽

Nail Polish ◽

Spatial Dimensions ◽

Non Destructive

Blood is key evidence to reconstruct crime scenes in forensic sciences. Blood identification can help to confirm a suspect, and for that reason, several chemical methods are used to reconstruct the crime scene however, these methods can affect subsequent DNA analysis. Therefore, this study presents a non-destructive method for bloodstain identification using Hyperspectral Imaging (HSI, 397–1000 nm range). The proposed method is based on the visualization of heme-components bands in the 500–700 nm spectral range. For experimental and validation purposes, a total of 225 blood (different donors) and non-blood (protein-based ketchup, rust acrylic paint, red acrylic paint, brown acrylic paint, red nail polish, rust nail polish, fake blood, and red ink) samples (HSI cubes, each cube is of size 1000 × 512 × 224, in which 1000 × 512 are the spatial dimensions and 224 spectral bands) were deposited on three substrates (white cotton fabric, white tile, and PVC wall sheet). The samples are imaged for up to three days to include aging. Savitzky Golay filtering has been used to highlight the subtle bands of all samples, particularly the aged ones. Based on the derivative spectrum, important spectral bands were selected to train five different classifiers (SVM, ANN, KNN, Random Forest, and Decision Tree). The comparative analysis reveals that the proposed method outperformed several state-of-the-art methods.

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Copper-graphene heterostructure for back-end-of-line compatible high-performance interconnects

npj 2D Materials and Applications ◽

10.1038/s41699-021-00216-1 ◽

2021 ◽

Vol 5 (1) ◽

Author(s):

Myungwoo Son ◽

Jaewon Jang ◽

Yongsu Lee ◽

Jungtae Nam ◽

Jun Yeon Hwang ◽

...

Keyword(s):

High Performance ◽

Direct Synthesis ◽

Chemical Vapor ◽

Multilayer Graphene ◽

Time To Failure ◽

Practical Applications ◽

Cu Interconnects ◽

Pressure Chemical ◽

Cu Interconnect ◽

Pure Cu

AbstractHere, we demonstrate the fabrication of a Cu-graphene heterostructure interconnect by the direct synthesis of graphene on a Cu interconnect with an enhanced performance. Multilayer graphene films were synthesized on Cu interconnect patterns using a liquid benzene or pyridine source at 400 °C by atmospheric pressure chemical vapor deposition (APCVD). The graphene-capped Cu interconnects showed lower resistivity, higher breakdown current density, and improved reliability compared with those of pure Cu interconnects. In addition, an increase in the carrier density of graphene by doping drastically enhanced the reliability of the graphene-capped interconnect with a mean time to failure of >106 s at 100 °C under a continuous DC stress of 3 MA cm−2. Furthermore, the graphene-capped Cu heterostructure exhibited enhanced electrical properties and reliability even if it was a damascene-patterned structure, which indicates compatibility with practical applications such as next-generation interconnect materials in CMOS back-end-of-line (BEOL).

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Identification of pigments in artworks by inverse tangent derivative of spectrum and a new filtering method

Heritage Science ◽

10.1186/s40494-020-00438-4 ◽

2020 ◽

Vol 8 (1) ◽

Author(s):

F. Fazlali ◽

S. Gorji Kandi

Keyword(s):

Reflectance Spectrum ◽

Practical Method ◽

Chemical Methods ◽

Munk Function ◽

Absorption Of Light ◽

Spectrophotometric Data ◽

First Time ◽

Non Destructive ◽

Derivatives Of

Abstract Employing an economical and non-destructive method for identifying pigments utilized in artworks is a significant aspect for preserving their antiquity value. One of the non-destructive methods for this purpose is spectrophotometry, which is based on the selected absorption of light. Mathematical descriptive methods such as derivatives of the reflectance spectrum, the Kubelka–Munk function and logarithm have been employed for the characterization of the peak features corresponding to the spectrophotometric data. In the present study, the mentioned mathematical descriptive methods were investigated with the aim to characterize the constituents of an Iranian artwork but were not efficient for the samples. Therefore, inverse tangent derivative equation was developed on spectral data for the first time, providing considerable details in the profile of reflectance curves. In the next part, to have a simpler and more practical method it was suggested to use filters made up of pure pigments. By using these filters and placing them on the samples, imaging was done. Then, images of samples with and without filter were evaluated and pure pigments were distinguished. The mentioned methods were also used to identify pigments in a modern Iranian painting specimen. The results confirmed these methods with reliable answers indicating that physical methods (alongside chemical methods) can also be effective in determining the types of pigments.

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Microparticles, Microspheres, and Microcapsules for Advanced Drug Delivery

Scientia Pharmaceutica ◽

10.3390/scipharm87030020 ◽

2019 ◽

Vol 87 (3) ◽

pp. 20 ◽

Cited By ~ 35

Author(s):

Miléna Lengyel ◽

Nikolett Kállai-Szabó ◽

Vince Antal ◽

András József Laki ◽

István Antal

Keyword(s):

Drug Delivery ◽

Drug Delivery Systems ◽

Freeze Drying ◽

Delivery Systems ◽

The Novel ◽

Practical Applications ◽

Inhaled Insulin ◽

Formulation Factors ◽

Novel Drug ◽

Significant Production

Microparticles, microspheres, and microcapsules are widely used constituents of multiparticulate drug delivery systems, offering both therapeutic and technological advantages. Microparticles are generally in the 1–1000 µm size range, serve as multiunit drug delivery systems with well-defined physiological and pharmacokinetic benefits in order to improve the effectiveness, tolerability, and patient compliance. This paper reviews their evolution, significance, and formulation factors (excipients and procedures), as well as their most important practical applications (inhaled insulin, liposomal preparations). The article presents the most important structures of microparticles (microspheres, microcapsules, coated pellets, etc.), interpreted with microscopic images too. The most significant production processes (spray drying, extrusion, coacervation, freeze-drying, microfluidics), the drug release mechanisms, and the commonly used excipients, the characterization, and the novel drug delivery systems (microbubbles, microsponges), as well as the preparations used in therapy are discussed in detail.

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