Vibration Energy Harvesting Using Piezoelectric Elements by Multi-switch Circuit with Adaptive Inductance

Salar Hatam,Saber Mohammadi,Akram Khodayari 제어·로봇·시스템학회 2021 International Journal of Control, Automation, and Vol.19 No.11

Mechanical vibration energy harvesting using multi-switch circuit with adaptive inductance is a new method based on impedance matching between electrical circuit and mechanical vibrating system in order to maximize the harvested energy. Considering a vibrating piezoelectric element in parallel with a load resistance, the whole converted energy is not dissipated or flowed into the load resistance and a remarkable portion of this energy is stored on the internal capacitor of the piezoelectric. By connecting the vibrating piezoelectric to a special interface circuit, approximately the whole stored energy portion on the piezoelectric flows into the circuit. The proposed interface circuit contains a set of inductors in series with electronic switches that controlled by a microcontroller which always provides resonance condition in the designed frequency range. In the proposed technique, for a simulated piezoelectric generator with a constant current source in the design frequency range of 100 to 700 Hz, the harvested power of numerical analysis is 2 to 10 times (depending on frequency) more than standard method (simple resistive circuit). Harvested power in the exprimental test for a cantilever piezoelectric plate in the design frequency of 100 to 350 Hz, is 4.5 times more than standard method.

Polyamines, Affected the Nitrogen Partitioning, Protein Accumulation and Amino Acid Composition of Mung Bean Under Water Stress

Salar Farhangi-Abriz,Reza Faegi-Analou,Neda Nikpour-Rashidabad 한국작물학회 2017 Journal of crop science and biotechnology Vol.20 No.4

Field experiments were conducted in two growing seasons as a split plot based on a randomized complete block design with four replications. Irrigation intervals (irrigation after 70 and 170 mm evaporation from class A pan) were assigned to main plots and spraying of polyamines (putrescine 0.1 mM, spermidine 0.1 mM, and spermine 0.1 mM) were allocated to the subplots. T nitrogen and sulfur content of different parts of mung bean, nitrogen uptake, protein filling duration, protein percentage of grain, maximum protein content per grains, grain and protein yields per unit area, methionine and serine contents reduced under water limitation, but grain filling rate, isoleucine, leucine, threonine, aspartic acid, glutamic acid, glycine, proline, tyrosine and arginine contents in grains raised. Treatment of plants with polyamines improved the contents of nitrogen and sulfur, nitrogen uptake, protein-filling duration, protein percentage, grain and protein yield per unit area, and histidine, methionine, phenylalanine, threonine, aspartic acid, glutamic acid, tyrosine, and arginine contents in grain. Putrescine had the highest grain and protein yields. Our results clearly indicated that polyamines with improving histidine, methionine, phenylalanine, and threonine content in mung bean grains improved the quality of mung bean protein.

A novel durable photoactive nylon fabric using electrospun nanofibers containing nanophotocatalysts

Salar Zohoori,Loghman Karimi,Sahar Ayaziyazdi 한국공업화학회 2014 Journal of Industrial and Engineering Chemistry Vol.20 No.5

This study explores new technique to produce a nylon fabric with durable self-cleaning property. Nylon fabric (polyamide 66) has been coated with electrospun nylon nanofibers containing nanoparticles (TiO2, SrTiO3 and ZnO). The coated samples were heat-setted in order to fixation of the nanofibers on surface of the nylon fabric. The self-cleaning property is tested by discoloration of the stained fabric with Direct Green 6 under UV irradiation. The scanning electron microscopy (SEM) images and X-ray diffraction (XRD) patterns were employed to characterize the treated nylon fabrics. The treated fabrics showed excellent photoactivity toward dye degradation. Moreover, the photoactivity of the treated fabrics stable after repeat laundering.

Investigation of the Progressive Collapse in a Suspension Bridge Under the Explosive Load

Salar Farahmand-Tabar,Majid Barghian,Majid Vahabzadeh 한국강구조학회 2019 International Journal of Steel Structures Vol.19 No.6

Progressive collapse is a continuous spread of initial local failure from one member to another one, fi nally causing the collapse of the structure entirely or a disproportionately large part of it. This disproportionate collapse is due to the small initial local failure induced by unpredicted attacks, exhibiting that the structural system cannot resist the development of damage due to the insuffi cient load carrying capacity. In this study, a typical suspension bridge was modeled and analyzed under explosion load. For this purpose, diff erent scenarios were investigated. Forces and moments of the superstructure, responses and the stability of the structure under the applied loads were studied. Explosion applied on the structure depends on the amount of the load and local eff ects. Also, by removing one or several elements of structures, the force is distributed in the whole structure. For loading rate on diff erent positions of the structure, it was observed that the critical position would be under the explosion and towers adjacent. Towers adjacent and the middle of the deck were prone to the maximum infl uences where should be put more attention on and be reinforced to preserve the structure from the total and local failure.

Design and synthesis of potential nano-carrier for delivery of diphencyprone to hair follicle

Hooshyar Salar,Nafisi Shohreh,Mohseni Mojdeh,Mehravi Bita 한국약제학회 2021 Journal of Pharmaceutical Investigation Vol.51 No.2

Purpose Poor bioavailability of diphenylcyclopropenone (DPCP), an effective drug for an autoimmune disorder of alopecia areata, limits its pharmaceutical effects. Carriers-based nanoparticles with especially porous structures can overcome these restrictions. Here, mesoporous silica nanoparticles, MCM41, with high surface area and pore volume were synthesized for DPCP delivery to the hair follicles through skin tissue. Methods Mesoporous silica nanoparticles (MCM41) were synthesized by the Stöber process and analyzed by scanning electron microscopy, dynamic light scattering, Barrett–Joiner–Halenda and N2 adsorption isotherms for their physicochemical properties. HPLC method was used to determine drug entrapment efficiency and release behavior during 24 h. Cytotoxicity of formulations was evaluated using MTT assay and permeation profiles of DPCP (control sample) and DPCP-MCM41 into the rat skin were obtained by using Franz diffusion cells. Fluorescence microscopy and intrafollicular nanoparticle accumulation were examined using confocal microscopy. Results Experiments showed the spherical shape of the nanoparticles with an average size of 50 ± 3 nm, high surface area, and porosity. Entrapment efficiency was about 90% and release behavior had sustained manner after 3 h. Fluorescent and confocal microscopy confirmed that the nanoparticles passed through follicular channels and aggregated around the hair follicles. Conclusion MCM41 nanoparticles provide a promising nano-carrier for targeted drug delivery of DPCP to the human hair follicle.

Special Function Inverse Series Pairs

Alsardary, Salar Yaseen,Gould, Henry Wadsworth Department of Mathematics 2010 Kyungpook mathematical journal Vol.50 No.2

Working with the various special functions of mathematical physics and applied mathematics we often encounter inverse relations of the type $F_n(x)=\sum\limits_{k=0}^{n}A^n_kG_k(x)$ and $ G_n(x)=\sum\limits_{k=0}^{n}B_k^nF_k(x)$, where 0, 1, 2,$\cdots$. Here $F_n(x)$, $G_n(x)$ denote special polynomial functions, and $A_k^n$, $B_k^n$ denote coefficients found by use of the orthogonal properties of $F_n(x)$ and $G_n(x)$, or by skillful series manipulations. Typically $G_n(x)=x^n$ and $F_n(x)=P_n(x)$, the n-th Legendre polynomial. We give a collection of inverse series pairs of the type $f(n)=\sum\limits_{k=0}^{n}A_k^ng(k)$ if and only if $g(n)=\sum\limits_{k=0}^{n}B_k^nf(k)$, each pair being based on some reasonably well-known special function. We also state and prove an interesting generalization of a theorem of Rainville in this form.

Optimization of Ultrasound-assisted Extraction of Phenolic Compounds from Yarrow (Achillea beibrestinii) by Response Surface Methodology

Davoud Salar Bashi,Seyyed Ali Mortazavi,Karamatollah Rezaei,Ahmad Rajaei,Mohamad Mahdi Karimkhani 한국식품과학회 2012 Food Science and Biotechnology Vol.21 No.4

An efficient ultrasound-assisted extraction (UAE)technique was applied to extract total phenolic content (TPC) from yarrow (Achillea beibrestinii). A response surface methodology was employed to evaluate the effects of 4 independent variables (temperature, pH, solvent to sample ratio, and time) on the TPC. The optimum extraction conditions were as follows: liquid to solid ratio 20, pH 6.3, extraction temperature 35oC, and extraction time 35 min. Under the above-mentioned conditions, the experimental TPC was 11.7 mg gallic acid equivalent/g dry matter. EC50 of the UAE extract at optimal conditions was found at 30.6±0.6 mg/L level and total flavonoids (TF)were obtained at 12.6±0.2 mg/10 g sample. Also, the results of HPLC analysis showed that gallic acid and pcoumaric acid were the predominant phenolic compounds in the plant.

Penetrating right ventricular injury following a single gunshot to the left flank in Iraq: a case report

Majeed Zryan Salar,Othman Yad N.,Ali Razhan K. 대한외상학회 2023 大韓外傷學會誌 Vol.36 No.3

A century ago, cardiac injuries usually resulted in death. However, despite all the advances in medicine, these injuries still have high mortality and morbidity rates. In the present case, we describe a patient with a bullet injury to the right ventricle who survived at our hospital despite the limitations of our center with regard to modalities and equipment. A 30-year-old man was brought to our emergency department with a bullet wound to his left flank. He was hemodynamically unstable. After only 8 minutes in the hospital and without further investigations he was rushed to the operating room. During laparotomy, a clot was visible in the left diaphragm, which dislodged and caused extensive bleeding. The decision was made to perform a sternotomy in the absence of a sternal saw. An oblique 8-cm injury to the right ventricle was discovered following rapid exploration. It was repaired without the need for cardiopulmonary bypass surgery. After a few days in the hospital, the patient was discharged home. In the event of a penetrating cardiac injury, rapid decision-making is crucial for survival. Whenever possible, the patient should be transferred to the operating room, as emergency department thoracotomies are associated with a high mortality rate.

In vitro antioxidant and free radical scavenging activities of stem extract of Euphorbia trigona Miller

Raj Kumar Salar,Pooja Sharma,Sukhvinder Singh Purewal 셀메드 세포교정의약학회 2015 TANG Vol.5 No.2

Antioxidative and free radical scavenging properties of different stem extracts of Euphorbia trigona were evaluated and correlated with its total phenolic content. Aqueous, acetone and methanolic extracts of shade dried stem were obtained and were concentrated in vacuo. The antioxidant and free radical scavenging activities of stem extracts was determined by 2,2-Diphenyl-1-picrylhydrazyl (DPPH) scavenging assay, reducing power assay, deoxyribose degradation assay and Fe2+chelating assay. Total phenolic contents (TPC) were evaluated using Folin-Ciocalteu reagent. The results confirmed that the plant is a rich source of polyphenolic compounds which are invariably higher compared to other herbs. All extracts showed TPC in the range of 146.6 – 168.6 mg/g gallic acid equivalents at 300 µg/ml of extract. Among the three extracts ME showed highest scavenging activity as evidenced by maximum scavenging of DPPH (83.2%), OH• radicals (94.81%), Fe2+chelating activity (88.59%) and a high reducing power 0.623 at 300 µg/ml. Our results demonstrate that Euphorbia trigona, an unexplored xerophytic plant could be potential source of natural antioxidants and phytotherapeutic agents. The plant possess invariably high amount of polyphenolic compounds with a broad spectrum of antioxidant properties and could be further used for food, feed and pharmaceutical applications.

Modulation of Phenolic Content and Antioxidant Activity of Maize by Solid State Fermentation with Thamnidium elegans CCF 1456

Raj Kumar Salar,Milan Certik,Vlasta Brezova 한국생물공학회 2012 Biotechnology and Bioprocess Engineering Vol.17 No.1

Thamnidium elegans CCF 1456, a filamentous fungus, was used to enhance the total phenolic content and radical scavenging activity of maize via solid-state fermentation. Thamnidium fermented maize (TFM) and unfermented maize (UFM) grains were extracted with 65%ethanol and dimethylsulfoxide (DMSO). Total phenolic content (TPC), and radical scavenging capacity – determined with 1,1-diphenyl-2-picrylhydrazyl (DPPH) and radical cations of 2,2'-azino-bis(3-ethylbenzothiazoline-6-sulfonate) (ABTS•+) found for TFM – were significantly (P < 0.05) higher on the 5th day of incubation than that of UFM extracts. A linear correlation was observed among TPC, DPPH and ABTS scavenging activities, and also among TPC and various carbohydrate-cleaving enzymes (α-amylase, β-glucosidase and xylanase), suggesting that this? strategy may help to enrich? TFM with improved phytochemical properties and antioxidant activities. Thamnidium elegans CCF 1456, a filamentous fungus, was used to enhance the total phenolic content and radical scavenging activity of maize via solid-state fermentation. Thamnidium fermented maize (TFM) and unfermented maize (UFM) grains were extracted with 65%ethanol and dimethylsulfoxide (DMSO). Total phenolic content (TPC), and radical scavenging capacity – determined with 1,1-diphenyl-2-picrylhydrazyl (DPPH) and radical cations of 2,2'-azino-bis(3-ethylbenzothiazoline-6-sulfonate) (ABTS•+) found for TFM – were significantly (P < 0.05) higher on the 5th day of incubation than that of UFM extracts. A linear correlation was observed among TPC, DPPH and ABTS scavenging activities, and also among TPC and various carbohydrate-cleaving enzymes (α-amylase, β-glucosidase and xylanase), suggesting that this? strategy may help to enrich? TFM with improved phytochemical properties and antioxidant activities.