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Hot Air Oven for Sterilization: Definition & Working Principle
Abstract
11Hot Air Oven for Sterilization: Definition & Working PrincipleHot Air Oven for Sterilization: Definition & Working PrincipleSaif Aldeen Saad ObayesMIEEESaifaldeen.Saad@ieee.orgSummaryAhot air ovenis a type of dry heat sterilization.Dry heatsterilization is used on equipment that cannot be wet and on material that will not melt, catch fire, or change form when exposed to high temperatures. Moist heat sterilization uses water to boil itemsor steam them to sterilize and doesn't take as long as dry heat sterilization. Examples of items that aren't sterilized in a hot air oven are surgical dressings, rubber items, or plastic material.Items that are sterilized in a hot air oven include:Glassware (like petri dishes, flasks, pipettes, and test tubes)Powders (like starch, zinc oxide, and sulfadiazine)Materials that contain oilsMetal equipment (like scalpels, scissors, and blades)Hot air ovens use extremely high temperatures over severalhours to destroy microorganisms and bacterial spores. The ovens useconductionto sterilize items by heating the outside surfaces of the item, which then absorbs the heat and moves it towards the center of the item.The commonly-used temperatures and timethat hot air ovens need to sterilize materials is 170 degrees Celsius for 30 minutes, 160 degrees Celsius for 60 minutes, and 150 degrees Celsius for 150 minutes.Hot air ovens sterilize equipment over long periods of time, so she has to be organized in determining what items will be sterilized at what time. This depends on when the equipment needs to be available again. Gina's manager now explains the different types of hot air ovens.
... Each student was examined in an appropriate room in his school, sat in a straight chair with a lofty back on which the student's head could be supported. During the inspection, a portable light was utilized for illumination [27], and the equipment were sanitized in a hot air oven at 160 degrees Celsius for one hour [28]. The criteria used to assess the MIH is the European Academy of Pediatric Dentistry that is scored as 0 ,1,2,3,4 and 5 ,interprtated as Normal, Demarcated opacity, Posteruptive enamel breakdown, A typical restoration and Extraction molar due to MIH and Unerupted molar due to MIH ,respectively [29]. ...
Background: Molar incisor hypomineralization is a clinical symptom of general hypomineralization affecting a single or multiple first permanent molars, which is generally accompanied with incisors. Objective: To determine the prevalence of molar incisor hypomineralization among 12 years students in Baquba city. Patients and Methods: This study was conducted from middle of January 2022 till the end of May 2022 in Baqubah city/Diyalla Governorate/Iraq. The sample excluded all students who had other enamel defects (fluorosis or hypoplasia, uncooperative students and students who refuse to participate. Results: Out of 700 participants, 52.43% of them were females and the rest were males. About 13% of the total sample showed a molar incisor hypomineralization, with significant association between gender, in which male were significantly more affected than females. The data showed 13% of the total sample had a demarcated opacities . Also the results showed that the upper centrals were more affected by hypominrlization than other teeth. Conclusion: However, the study revealed that demarcated opacity was the most common form of defect with a significant correlation, with a frequency of 13%. The upper central tooth was always the most commonly impacted by molar incisor hypomineralization.
... Pada metode ini digunakan suhu yang sangat tinggi selama beberapa jam dengan tujuan untuk membunuh atau menghilangkan agen yang menjadi penyebab kontaminasi pada kultur jaringan (seperti s p o r a j a m u r d a n b a k t e r i ) . O v e n b e k e r j a menggunakan proses konduksi panas dengan terlebih dahulu memanaskan permukaan bagian luar peralatan, kemudian menyerap panas dan memindahkannya ke bagian tengah alat tersebut (Alkhadim, 2018). Oven yang digunakan harus memiliki kipas yang terpasang di dalamnya dengan tujuan agar sirkulasi udara panas dapat berjalan dengan baik. ...
Plant tissue culture is a technology used to propagate plants under controlled and aseptic environmental conditions. One of the obstacles in tissue culture activities is the presence of bacterial and fungal contamination. Equipment and growing media that are used for tissue culture can be the source of contamination. The method that can be used to reduce contamination is using sterilization. Sterilization is used to kill or eliminate microorganisms so that the equipment and media are free from contaminants. Equipment sterilization can be done through several methods such as wet sterilization and dry sterilization. Wet sterilization is carried out using an autoclave, while dry sterilization can be carried out using an oven, fire, and glass bead sterilizer. Media sterilization is generally carried out using an autoclave or membrane filter.
... Similarly, surface degradation and particle aggregations are increased in the order of HAO > MW > AL > native EFYS, which is also confirmed by the following experiments (atomic force microscopy and particle size analysis, respectively). The severity can be related to the fact that HAO treatment heats the starch from the outside in, whereas AL heating with pressure reveals homogeneous distribution of thermal energy causing less surface irregularities (Alkadhim, 2018;Barua, Khuntia, Srivastav, & Vilgis, 2021). However, during microwave treatment, collision and friction between polar water molecules may cause the surface damages but with less impact as compared to HAO treated one (Han et al., 2021). ...
Starch isolated from elephant foot yam (Amorphophallus paeoniifolius) was modified by heat moisture treatment (HMT) using various heating sources viz. hot air oven (HAO), autoclave (AL), and microwave (MW). Morphology, surface roughness, thermal, structural, and dynamic rheological properties of native and HMT modified elephant foot yam starch (EFYS) were evaluated. Surface cracks, pitting, and scratching were prominent on the granules after modification, leading to an increase in surface roughness. HAO treated EFYS exhibited the highest formation of agglomerations and an increase in particle size compared to other treatments. All the modified EFYS samples had a significant increase in amylose content, and the highest was observed in HAO treatment. An increase in gelatinization temperature and reduction in gelatinization enthalpy were observed in HMT EFYS. Relative crystallinity was reduced in HMT modified EFYS which varied in the range of 35–41% as compared to native EFYS of 43%. A decrease in molecular weight from native 6.39 × 10⁷g/mol to HMT modified EFYS was observed which varied in the range 4.51–5.37 × 10⁷g/mol. Interestingly, the increase in elastic behavior was noticed in all modified EFYS compared to native EFYS and the highest increment was noted in HAO treated EFYS, suggesting the formation of a strong gel network under high shear. The Pearson correlation studies showed that particle size and short amylopectin chain fractions have significant positive correlation with dynamic moduli of EFYS. HMT using HAO treatment resulted in improved characteristics of EFYS and extended the range of its use in food processing.
Microbiology is the study of microorganisms biological entities too small to be seen with the unaided eye. Most major advances in microbiology have occurred within the past 150 years, and several important subdisciplines of microbiology have developed during this time, including microbial ecology, molecular biology, immunology, industrial microbiology and biotech- nology. Microorganisms of various types exist in all three domains of life (the Bacteria, Archaea and Eukarya), and they are by far the most abundant life forms on Earth. Microscopic biological agents include bacteria, archaea, protists (protozoa and algae), fungi, parasitic worms (helminths) and viruses. Although a small percentage of microorganisms are harmful to certain plants and animals and may cause serious disease in humans, the vast majority of microorganisms provide beneficial services, such as assisting in water purification and the production of certain foods, and many are essential for the proper functioning of Earth's ecosystems. Molecular biology has revolutionized our understanding of the diversity, function, and community structure of marine microorganisms. Increasingly, tools and techniques derived from the biomedical diagnostics and research industries are used in parallel with sensors that characterize the physical, chemical, and optical properties of ocean waters.
Microbiology is the study of microorgan- isms biological entities too small to be seen with the unaided eye. Most major advances in microbiology have occurred within the past 150 years, and several important subdisciplines of microbiology have developed during this time, including microbial ecology, molecular biology, immunology, industrial microbiology and biotech- nology. Microorganisms of various types exist in all three domains of life (the Bacteria, Archaea and Eukarya), and they are by far the most abundant life forms on Earth. Microscopic biological agents include bacteria, archaea, protists (protozoa and algae), fungi, parasitic worms (helminths) and viruses. Although a small percentage of microor- ganisms are harmful to certain plants and animals and may cause serious disease in humans, the vast majority of microorganisms provide beneficial services, such as assisting in water purification and the production of certain foods, and many are essential for the proper functioning of Earth's ecosystems. Molecular biology has revolutionized our understanding of the diversity, function, and community structure of marine microorganisms. Increasingly, tools and techniques derived from the biomedical diagnostics and research industries are used in parallel with sensors that characterize the physical, chemical, and optical properties of ocean waters.
Bacteria influence plant growth and development and therefore are attractive resources for applications in agriculture. However, little is known about the impact of these microorganisms on secondary metabolite (SM) production by medicinal plants. Here we assessed, for the first time, the effects of bacteria on the modulation of SM production in the medicinal plant Lithospermum officinale (Boraginaceae family) with a focus on the naphthoquinones alkannin/shikonin and their derivatives (A/Sd). The study was conducted in an in vitro cultivation system developed for that purpose, as well as in a greenhouse. Targeted and non-targeted metabolomics were performed, and expression of the gene PGT encoding for a key enzyme in the A/S biosynthesis pathway was evaluated with qPCR. Three strains, Chitinophaga sp. R-73072, Xanthomonas sp. R-73098 and Pseudomonas sp. R-71838 induced a significant increase of A/Sd in L. officinale in both systems, demonstrating the strength of our approach for screening A/Sd-inducing bacteria. The bacterial treatments altered other plant metabolites derived from the shikimate pathway as well. Our results demonstrate that bacteria influence the biosynthesis of A/Sd and interact with different metabolic pathways. This work highlights the potential of bacteria to increase the production of SM in medicinal plants and reveals new patterns in the metabolome regulation of L. officinale.
3- phase distribution transformers generally have a Delta (Triangular) connected primary winding and a Star (Wye) connected secondary winding. The secondary Star configuration allows for a 3-phase and Neutral, Dy1 supply providing line and phase voltages and currents. Commonly the Neutral and Earth connections which provide a 5-wire (3-phases + Neutral + Earth) TN-S (separate Neutral and Earth) supply to homes and buildings are connected together at the star point of the three secondary windings, thus the Neutral and Earth are effectively bonded together and remain at the same zero or Earth potential. However, with a TN-C (combined Neutral and Earth) 4- wire (3-phases + Neutral) supply the Neutral wire also acts as the Earth wire, but the neutral wire is still bonded along with a separate Earth electrode to the star point of the secondary windings to provide the required phase voltages and currents. TT and IT configurations have different Neutral and Earthing arrangements. Being a Delta connected Primary winding and therefore a balanced load for the supplying network, there is no Neutral or Earth connection to the three primary windings, (Earthing is done at the generator source) but it is possible that the physical metal casing of the transformer has been bonded to the secondaries Earthing bar for safety.
AM generation involves mixing of a carrier and an information signal. In low level modulation, the message signal and carrier signal are modulated at low power levels and then amplified. The advantage of this technique is that a small audio amplifier is sufficient to amplify the message signal.
Fourier theory says that any periodic signal can be created by adding together different sinusoids (of varying frequency, amplitude and phase). In many applications, an unknown analog signal is sampled with an A/D converter and a Fast Fourier Transform (FFT) is performed on the sampled data to determine the underlying sinusoids.
In this steps a visual approach based on convolution is used to explain basic Digital Signal Processing (DSP) up to the Discrete Fourier Transform (DFT). The DFT is explained instead of the more commonly used FFT because the DFT is much easier to understand. (The DFT is equivalent to the FFT except the DFT is far less computationally efficient.)
In particular, convolution is shown to be the key to understanding basic DSP. Also, some of the concepts are far more intuitive in the frequency-domain vs. the more familiar time-domain.
The popularity of 3 phase induction motors on board ships is because of their simple, robust construction, and high reliability factor in the sea environment. A 3-phase induction motor can be used for different applications with various speed and load requirements. Electric motors can be found in almost every production process today. Getting the most out of your application is becoming more and more important in order to ensure cost-effective operations.
The Light Dependent Resistor (LDR) is made from a Cadmium-Sulfide compound (CdS). CdS is a semiconductor material. The resistance of the LDR changes as the light level changes. More light produces more electron – hole pairs in the material, making the material a better conductor in light. Resistance decreases (conductivity increases) as light levels increase because there are more charge carriers in the material. Note that R = 1/G (G is conductance)
The LDR controls the voltage on the transistor’s base. As it gets darker in the room, the voltage on the base will increase until the transistor is forward biased. This results in high current flowing from the transistor’s collector to the base. This collector current flows to the LED and is responsible for turning the LED on.
The light dependent resistor is an electronic component whose resistance decreases with increasing light intensity. It is also called as “Photo Resistor” or “Photo conductor”
The light dependent resistor uses high resistance semiconductor material.
When light falls on such a semiconductor the bound electrons [ ie., Valence electrons] get the light energy from the incident photos.
This paper focused on the development of Microstrip Antenna Array, which operates at 28 GHz where this frequency suggested as operating frequency for 5th Generation mobile technology. The proposed antenna structure is constructed with a single patch located in an array configuration within one plane. The antenna is fed from the backside via a coaxial fed. Normally in array antenna technology, researchers use full ground plane approach in order to meet a good antenna performance. The development of proposed antenna involved simulation, optimization, fabrication and measurement to get the best antenna performance at desired frequency. Simulation and optimization phase was done using Computer Simulation Technology (CST) software, which has the capability of giving a better look on performance of antenna in simplest way.
Cite: Saif Aldeen Saad Obayes Al-Kadhim, Ibtesam R. K. Al-Saedi, and Basil Jabir Shanshool, " Microstrip Grid Antenna Array for 5G Mobile Devices," Journal of Communications, vol. 13, no. 5, pp. 225-229, 2018. Doi: 10.12720/jcm.13.5. 225-229.
This paper explains how to connect and configure a Raspberry Pi so that it is able to communicate with a Pixhawk flight controller using the MAVLink protocol over a serial connection. This can be used to perform additional tasks such as image recognition which simply cannot be done by the Pixhawk due to the memory requirements for storing images.
This paper shows optimization of the Solar Cell block's parameters to fit data defined over a range of different temperatures. It uses the MATLAB® optimization function fminsearch. Other products available for performing this type of parameter fitting with Simscape™ Electronics™ models are the Optimization Toolbox™ and Simulink® Design Optimization™. These products provide predefined functions to manipulate and analyze blocks using GUIs or a command line approach. Strategy Fit I-V output curves for an 8 Parameter Solar Cell to data using a 2 step procedure: 1. Optimize parameters in the Solar Cell Main dialog tab to match output curves to data at room temperature. 2. Optimize parameters in the Solar Cell Temperature dialog tab to match output curves to data at non-room temperatures. Data and Block Setup The MATLAB data file, elec_solar_iv_data.mat, stores Solar Cell data as an array of structures. Each structure contains 3 fields: temperature , i (current) and v (voltage). The Solar Cell block references a data structure to set the device operating temperature, to set the VPulse block's pulse value and to generate simulation output currents at prescribed voltages specified in the Configuration Parameters Data Import/Export Pane Output times option under the Simulation menu. Scopes save the output voltage and current responses as structure data, Io.signal.values and Vo.signal.values. % Load Solar Cell data load elec_solar_iv_data.mat % Display the Solar Cell model Model = 'elec_solar'; open_system(Model) close_system(Model, 0);
One of the most essential features of speech signals is there no
stationary character. On account of that traditional short time Fourier
transform was used for processing speech signals for a long time. But
recently the wavelet transform became an alternative to this method.
Wavelet as the basis with localized both time interval and spectrum
width have essential advantages comparing with traditional spectral
basis. This property of wavelets is useful for speech signals processing.
The performance of the proposed speech scrambling system
based on wavelet transform was examined on actual speech signal, and
the results showed that there was not any residual intelligibility in the
scrambled speech signal, and descrambled speech signal at receiver
was exactly identical to the original. The performance of the proposed
scrambling system was compared with FFT and DCT, and we proved
that the scrambling system using wavelet transform is the best one,
since it provides the highest security scrambled speech signal and the
reconstructed signal was perfect.
This paper focus on the integration of wireless technology and CAD/CAM system for CNC workshop development. A specific case study is described a system based on embedded wireless device and Internet of Things (IoT) concept with Bezier techniques for the proposed model. The focus of the case study is to show a complete stage of manufacturing process starting from modeling in CAD system passing through CAM system, transferring NC code, gathering machine data, monitoring whole process and finally manufacturing product. Using MATLAB and UG-NX software for modeling, Monitoring machining process using temperature, accelerometers and gyroscope sensors based on IoT concept. Transferring NC codes to CNC machines using FTP protocol and DNC software, real-time report demonstrate information about machine name, parts progress, time, operation condition and Machine Cycle Time depending on DNC network.
This paper focus on the integration of wireless technology and CAD/CAM system for CNC workshop development. A specific case study is described a system based on embedded wireless device and Internet of Things (IoT) concept with Bezier techniques for the proposed model. The focus of the case study is to show a complete stage of manufacturing process starting from modeling in CAD system passing through CAM system, transferring NC code, gathering machine data, monitoring whole process and finally manufacturing product. Using MATLAB and UG-NX software for modeling, Monitoring machining process using temperature, accelerometers and gyroscope sensors based on IoT concept. Transferring NC codes to CNC machines using FTP protocol and DNC software, real-time report demonstrate information about machine name, parts progress, time, operation condition and Machine Cycle Time depending on DNC network.