Extraction Techniques of Phenolic Compounds from Plants

Phenolic derivatives are one of the most important compounds that were found in secondary metabolites in plants. According to their various applications in agriculture, food, chemical and pharmaceutical industries, interests in reviewing different procedures of extraction of these compounds from plants have increased. In this chapter, we would like to have an overview on the extraction procedures that have been used in isolating phenolic compounds from plants until this time, including liquid-liquid extraction (LLE), ultrasound-assisted extraction (UAE), microwave-assisted extraction (MAE) and supercritical fluid extraction (SFE). In the following, advantages and disadvantages of these techniques and methods will be discussed and explained. In addition, in the last part of this chapter, various methods for purification and identification of phenolic compounds will be presented

Identification of the Most Important Factors Driving Watermain Failure

As essential infrastructure, water distribution systems provide water to the vital needs of individuals, businesses, and industries. Watermain failure jeopardizes water systems' ability to deliver clean water safely. The main target of this study was to identify the most influential factors on watermain failure across Canada. Dimensionality reduction approaches were applied to watermain data from thirteen Canadian cities, Barrie, Calgary, Region of Durham, Halifax, Kitchener, Region of Markham, Region of Waterloo, Saskatoon, St. John’s, Vancouver, Victoria, Waterloo, and Winnipeg. While previous studies have focused on small datasets of a few cities at a time, the present study compares various factors in different networks with different characteristics. Multiple physical, historical, protection, operational, and environmental factors were compared. Two target attributes were defined, current rate of failure and break status. A correlation analysis was applied to each city to identify the relationships between different attributes and the targets. Four dimensionality reduction approaches were employed to evaluate the impacts of different factors on the targets and identify the most important factors The four approaches are Factor Analysis of Mixed Data (FAMD), Categorical PCA (CATPCA), Random Forest Recursive Feature Elimination (RF-RFECV), and Extreme Gradient Boosting Recursive Feature Elimination (XGBOOST-RFECV). Results indicate CATPCA is more reliable than other approaches. Furthermore, protection activities were found to be more important than physical and historical attributes in most utilities. Thus, the collection of protection data should be prioritized for utilities with higher rates of protection activities, especially if they have already collected data on fundamental physical and historical attributes. While few utilities collect data on environmental, operational, and certain physical factors such as roughness, dead-end, restrained, and pipe depth, these were also found to be important and should be further investigated. These findings create the foundation for a new data collection framework for predicting main breaks

Nonlinear optical characteristics of N,N’-bis(salicylidene)-p-phenylenediamine: Z-scan technique and quantum mechanical calculations

ABSTRACT. In this work, we have characterized the linear and nonlinear optical properties of N,N′-bis(salicylidene)-p-phenylenediamine (BSP) in both macroscopic and microscopic modes by using Z-scan technique and quantum chemical calculations. The microscopic nonlinear optical properties of BSP were investigated by density functional theory with the basis set of 6-311G++dp. Electronic properties such as frontier molecular energies, band-gap energy, electron affinity, hardness, softness, and ionization potential were evaluated. The calculation of microscopic quantities included first-order hyperpolarizability and natural bond orbitals showed the electron delocalization, which confirmed the nonlinear optical properties in this compound. The results of the absorption spectrum of BSP in DMSO, DMF, CH3Cl solvents were shown that the dissolved sample in DMSO had better nonlinear properties than others. Then the macroscopic nonlinear properties of the sample were determined by the Z-scan technique. The values of the nonlinear refractive index (n2), nonlinear absorption coefficient (β), and third-order nonsusceptibility of the sample in DMSO were, 0.09250×10-10 cm2/W, -0.174×10–6 cm/W and 4.101× 10-5 esu, respectively. The two-photon absorption in this molecule has been enhanced by the donor–bridge–donor (D–π–D) architecture. The theoretical and experimental results concluded that BSP seems to be promising candidates for future photonic and optoelectronic devices.                 KEY WORDS: Azo dye, Nonlinear optic, Hyperpolarizability, One photon absorption, Two photon absorption, Schiff bases   Bull. Chem. Soc. Ethiop. 2022, 36(2), 465-477.                                                               DOI: https://dx.doi.org/10.4314/bcse.v36i2.18                                                       &nbsp

Daylight Parameters and Operation Quality Case Studies: Public Office Buildings in Kerman, Iran

Most of existing government office building in Iran were designed and built without enough consideration to the daylight design. Therefore a lot of electricity energy should be used to provide visual comfort in office rooms in government office buildings. Due to location of Kerman City of Iran, There are a lot of solar radiation in whole year during working hours in exterior spaces. In this research daylight quality of 4 office rooms in 2 government office buildings in Kerman city of Iran were investigated through experimental measurement and calculating some daylight parameters such as mean Work PlaneIlluminance (WPI), Work Plane Illuminance Ratio (WPI Ratio) and daylight Ratioin two conditions when lights were on and off. Finding of this research reveals that most of office building in government building cannot reach the acceptable range of different parameters of daylight even though lights were on. Therefore research about daylight quality in office rooms in this region is an important issue to be investigated to find different methods and solutions for improving daylight quality in office rooms. Keywords: Daylight Quality, Government Office buildings, Working Plane Illuminance, Working Plane Illuminance Ratio, Daylight Facto

Modeling jumps in organization of petroleum exporting countries basket price using generalized autoregressive heteroscedasticity and conditional jump

This paper uses autoregressive jump intensity (ARJI) model to show that the oil price has both GARCH and conditional jump component. In fact, the distribution of oil prices is not normal, and oil price returns have conditional heteroskedasticity. Here the authors compare constant jump intensity with the dynamic jump intensity and evidences demonstrate that oil price returns have dynamic jump intensity. Therefore, there is strong evidence of time varying jump intensity Generalized Autoregressive Heteroscedasticity (GARCH) behavior in the oil price returns. The findings have several implications: first, it shows that oil price is highly sensitive to news, and it does settle around a trend in long-run. Second, the model separates variances of high volatilities from smooth volatilities. Third, the model rejects an optimal path for extracting oil and technology transmission. In fact, the lack of a long-term pattern can cause excessive oil extracting which can result in heavy climatic effects. Keywords: generalized autoregressive heteroscedasticity (GARCH), jumps, basket, oil price, Organization of Petroleum Exporting Countries (OPEC), Autoregre-ssive jump intensity (ARJI). JEL Classification: C32, C52, F3

THE EFFECT OF NANOPARTICLE ZnO ON ENVIRONMENT AND DIFFERENT ORGANIZMS (Review)

ABSTRACT: Nanotechnology has noticeably developed with potential effects in every science specially by using nanoscale chemical element. Among nano material ZnO is more attention due to its special properties and its less hazard to environmental impact. ZnO like most of nanoparticles is toxic in organiams, however the toxicity of this nanoparticles can be used for antibacterial, antifungal, antiviral and antialga. To reduce the hazard effect of nanoparticles some manufact or chemical particles such as Nanoscale zero-valent iron are introduce that can be used for environmental remediation of polluted water, soil and sediments. In the present study, the effect of Nanoparticle ZnO on environment and different organisms from virous to fish has been reviewed and the application of nanoscale material in treatment of water are discuss

Comparing the results of 3D treatment planning and practical dosimetry in craniospinal radiotherapy using Rando phantom

Background: Craniospinal radiotherapy faces technical challenges which are due to the sensitivity of the location in which the gross tumor is, and to organs at risk around planning target volume. Using modern treatment planning systems causes a reduction in the complexities of the treatment techniques. The most effective method to assess the dosimetric accuracy and the validity of the software used for treatment planning is to investigate the radiotherapy and treatment planning by means of a anthropomorphic Rando phantom which was used here for treatment planning and practical dosimetry for craniospinal radiotherapy. Studying the absorbed dose by the organs at risk was the secondary objective discussed in this paper. Materials and Methods: Treatment planning in craniospinal radiotherapy was done using CorePlan 3D treatment planning software. Radiotherapy was administered on a anthropomorphic Rando phantom and practical dosimetry was done using GR-200 TLDs. Varian Clinac 2100C/D was used for radiotherapy. Results: The absorbed dose by regions of interest was separately calculated for treatment planning and radiotherapy. Except the conjunction areas of the cranial and spinal radiation fields, the difference among the results was not more than 5. Full comparison of the results for each part has been presented. Conclusion: The comparison the results of practical dosimetry and treatment planning software supports the validity of CorePlan treatment planning system. Also analysis of the absorbed dose through organs at risk showed that the absorbed dose by organs at risk have an acceptable value with respect to tolerance dose of these organs. The only unacceptable result was related to thyroid