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Author(s):  
Salman Hameed

Abstract: Brick masonry structures are commonly used in world because of its simplicity and economy. However, it is susceptible to failure in earthquakes because of the bricks weak interlocking bonds and brick masonry structures designed mainly against gravity load demand. Therefore, in recent years research work has been conducted to confine the unreinforced brick masonry with reinforced concrete tie beams and column, to improve its seismic performance. This enhances both the lateral resistance and stability of the entire structure, to perform as one mass unit against the lateral forces. However, the effect of confining brick masonry through reinforced concrete member has been evaluated in the past only on testing single cantilever walls or single room. Therefore, this research work aims to evaluate its influence on large structures i.e., highlight its limitation and afterward mitigate the damages by introducing external FRP strengthening techniques. The structures configuration is based on the observation made in Pakistan’s rural areas where mostly brick masonry structure. Confined brick masonry walls are subjected to quasi static lateral loading, afterwards retrofitted with FRP and tested again. The test result discussion includes load response behavior, stiffness degradation, energy dissipation and damage indices. Keywords: Confined brick masonry, RC tie beam column, FRP, Retrofitting, Seismic analysis, Quasi Static


Fluids ◽  
2021 ◽  
Vol 6 (10) ◽  
pp. 354
Author(s):  
Otto G. Piringer

In this manuscript, a function is derived that allows the interactions between the atoms/molecules in nanoparticles, nanodrops, and macroscopic liquid phases to be modeled. One goal of molecular theories is the development of expressions to predict specific physical properties of liquids for which no experimental data are available. A big limitation of reliable applications of known expressions is that they are based on the interactions between pairs of molecules. There is no reason to suppose that the energy of interaction of three or more molecules is the sum of the pairwise interaction energies alone. Here, an interaction function with the limit value w = e2π/e is presented, which allows for the derivation of the atomic mass unit and acts as a bridge between properties of elementary particles and emergent properties of macroscopic systems. The following properties of liquids are presented using the introduced interaction function: melting temperatures of n-alkanes, nanocrystals of polyethylene, melting temperatures of metal nanoparticles, solid–liquid phase transition temperatures for water in nanopores, critical temperatures and critical pressures of n-alkanes, vapor pressures in liquids and liquid droplets, self-diffusion coefficients of compounds in liquids, binary liquid diffusion coefficients, diffusion coefficients in liquids at infinite dilution, diffusion in polymers, and viscosities in liquids.


2021 ◽  
Vol 17 (2) ◽  
pp. 59-71
Author(s):  
Yu. I. Kamenskikh ◽  
V. S. Snegov

The article discusses the calibration results of reference standards-copies according to the State Primary Standard of the Mass Unit using the new CCL 1007 vacuum comparator and buoyancy artifacts. The authors provided historical data on the calibrations of copies of the International Prototype of the Kilogram (IPK) starting from 1892, including the Russian prototype № 12. The instability of the prototype of the kilogram No. 12 corresponds to international values and is assessed at 5 · 10–11 kg per year. Changes in the mass of copies are assessed in relation to the mass of the IPK, but it is impossible to determine to what extent it has changed. This was the reason for the adoption of a new value of the kilogram. Following the adoption at the 26th meeting of the General Conference on Weights and Measures (CGPM) held in Paris in November 2018, Planck constant was numerically established with absolute accuracy, and total uncer tainty of 1 · 10–8 kg was assigned to the mass of the IPK. Thus, the authors set the aim to preserve the numerical value of the total uncertainty of the reference standards-copies by reducing the transfer error of the State Primary Standard by 10 times. The article presents the calibration results of six reference standards-copies in relation to prototype No. 12 with the primary data processing using the method of least squares, and the uncertainty budget is provided. The calibration results of the reference standards-copies confirmed the accuracy increase of the transfer unit by 10 times in the range from 6 · 10–9 kg to 6 · 10–10 kg by the use of a vacuum comparator graduated 0.1 μg and buoyancy and sorption artifacts in direct measurements of air density. This has made it possible to compensate for the additional uncertainty attributed to the IPK based on the determination of the Planck constant value and to ensure the mass calibration of all accuracy grades preserving the entire hierarchical system of transferring the mass unit in the country.


2021 ◽  
Vol 4 (3(60)) ◽  
pp. 46-49
Author(s):  
Svitlana Pavlenko ◽  
Yakov Verkhivker ◽  
Оlena Myroshnichenko

The object of research is the technology of functional fruit and vegetable juice products enriched with collagen. The subject of research is various types of collagen, formulations and parameters of technological operations for the production of functional juice drinks. The research is aimed at the develop technology, recipes for a new assortment of fruit and vegetable drinks enriched with collagen. Also it is aimed at the preserve the functional properties of collagen in canned juice products after high-temperature processing and create food products for everyday consumption to solve age-related and other problems associated with human health. In the course of the study, standard methods were used to determine the organoleptic indicators of various types of collagen, juice products, as well as to determine the mass fraction of moisture, carbohydrates, fats, proteins in the developed fruit and vegetable drinks enriched with collagen. Also, to confirm the presence and preservation of collagen in finished products, the electrophoresis method was used to determine the atomic mass unit of the constituent substances after complete drying of the samples. The proposed methods make it possible to assess the quality of the developed collagen-enriched drinks, prove the presence and preservation of a biologically active additive in the finished product after using the sterilization mode parameters – temperature and time, when receiving canned products. The developed formulations and technology make it possible to consider functional fruit and vegetable juice-containing products enriched with a biologically active additive collagen as effective and useful. An easily digestible food product for everyday consumption is proposed for solving age-related and other problems related to human health, with regulation of the pH value for effective use of the beneficial properties of this additive. In contrast to existing functional juice products, the proposed formulations and technology make it possible to obtain juice-containing fruit and vegetable blended products with a biologically active additive collagen. The technology minimizes the impact of collagen on the organoleptic characteristics of the developed recipe compositions of finished products and preserves its beneficial biologically active properties in the finished canned product after heat sterilization.


Water ◽  
2021 ◽  
Vol 13 (14) ◽  
pp. 1954
Author(s):  
Konstantina Fotia ◽  
Andi Mehmeti ◽  
Ioannis Tsirogiannis ◽  
George Nanos ◽  
Andreas P. Mamolos ◽  
...  

Olive cultivation is expanding rapidly in the northwestern part of Greece, under both rainfed and irrigated practices. Irrigation can result in larger yields and economic returns, but trade-offs in the water–energy–pollution nexus remain a controversial and challenging issue. This study presents an environmental Life Cycle Assessment (LCA) of Greek olive orchard systems in the plain of Arta (Epirus), comparing rainfed (baseline), Decision Support System (DSS)-based (smart) irrigation practices and farmer experience-based (conventional) irrigation practices. The contributions in this paper are, first, to provide a first quantitative indication of the environmental performance of Greek olive growing systems under different management strategies, and second, to detail the advantages that can be achieved using smart irrigation in olive cultivation in the Greek and Mediterranean contexts. Eighteen midpoints (e.g., climate change, water scarcity, acidification, freshwater eutrophication, etc.), two endpoints (damages on human health and ecosystem quality), and a single score (overall environmental impact) were quantified using the IMPACT World+ life cycle impact assessment method. The LCA model was set up using the OpenLCA software v1.10.3. The functional units were 1 ton of product (mass-based) and 1 ha of cultivated area (area-based) on a cradle-to-farm gate perspective. Irrigated systems had the lowest impacts per mass unit due to higher yields, but showed the highest impacts per cultivated area. The DSS-based irrigation management could reduce water and energy use by 42.1% compared to conventional practices. This is translated into a reduction of 5.3% per 1 ton and 10.4% per 1 ha of the total environmental impact. A sensitivity analysis of impact assessment models demonstrated that the benefits could be up to 18% for 1 ton of product or 22.6% for 1 ha of cultivated land. These results outline that DSS-based irrigation is a promising option to support less resource-intensive and sustainable intensification of irrigated agriculture systems in the plain of Arta.


Author(s):  
Kun Wu ◽  
Haiyan Hu ◽  
Lifeng Wang

The optimal design is studied for a type of one-dimensional dissipative metamaterial to achieve broadband wave attenuation at low-frequency ranges. The complex dispersion analysis is made on a super-cell consisting of multiple mass-in-mass unit cells. An optimization algorithm based on the sequential quadratic programming method is used to design the wave suppression of target frequencies by coupling multiple separate narrow bandgaps into a broad bandgap. A new objective function is proposed in the optimization process for a continuous bandgap. Then, the continuous frequency range with low-wave transmissibility is optimized to achieve the maximal width of bandgap. The stiffness optimization of super-cell gives the broad bandgap from 10 Hz to 22.9 Hz at low-frequency ranges. In addition, numerical simulations are conducted for a type of dissipative metamaterial composed of a finite number of periodicities. The level of vibration isolation can be tuned by adjusting a critical value in the optimization scheme. The wave suppression in the numerical simulation well coincides with the obtained bandgaps and verifies the optimization results.


Author(s):  
Tomasz Piechowiak ◽  
Bartosz Skóra ◽  
Katarzyna Grzelak-Błaszczyk ◽  
Michał Sójka

AbstractThe purpose of this study was to investigate the biological properties of an extract obtained from the waste of blueberry fruit. The study covered the optimization of extraction of antioxidants from blueberry pomace and the determination of antioxidant properties of the extract using HaCaT as the model organism. Research showed that the yield of antioxidants extraction from blueberry waste was dependent on the applied extraction conditions. Based on the mathematical models, the optimal conditions of extraction process in which the maximum quantity of antioxidant compounds is achieved from the waste mass unit, i.e., the relation of the waste mass to the volume of ethanol equal to 1:17.36, and process time equal to 1000 s. The obtained extract was characterized by high antioxidant activity, which was shaped by high content of polyphenols, mainly anthocyanins. Moreover, the extract showed a high ability to protect HaCaT cells from the occurrence of oxidative stress induced by H2O2. Cells treated with the extract and H2O2 generated a lower amount of ROS than cells treated with H2O2 only. The obtained results will be base of further studies on applying the extract in production of diet supplements and functional foods with increased antioxidant activity. Moreover, the main research material is blueberry pomace which is a troublesome waste material for juice producers. Consequently, according to a sustainable development idea, the study results will provide an opportunity to increase interest in the problem of rational use of the waste material to a certain extent.


2021 ◽  
Vol 7 (5) ◽  
pp. 67
Author(s):  
Luca Cirillo ◽  
Adriana Farina ◽  
Adriana Greco ◽  
Claudia Masselli

Italy has not yet presented to the scientific community any elastocaloric prototype suitable for refrigeration/air conditioning. The SUSSTAINEBLE project was born from the idea to build a demonstrative elastocaloric prototype for environmental conditioning. The prototype is planned to be rotary and composed by a few bunches of elastocaloric wires crossed by air as heat transfer fluid. Many are the parameters to be investigated before the realization of the device. A numerical practical tool would help to easily optimize the prototype. In this paper a two-dimensional tool of a single bunch of elastocaloric wires based on finite-element method is introduced; it can reproduce step by step the velocity and the pressure field of fluid to predict more accurately the solid-to-fluid heat exchange. The results of a test campaign mostly focused on the optimization of the frequency of the cycle, fluid velocity and the distance between the elastocaloric wires are presented. The results reveal that: (i) 0.12 Hz as frequency; (ii) 7 m s−1 as velocity; (iii) 1.0 mm as optimal wire distance, would better satisfy the trade-off existing in the maximization of temperature span and cooling power per mass unit: 23.7 K and 311.97 W kg−1 are the values achieved, respectively.


Author(s):  
Inês Francisco ◽  
Francisco Caramelo ◽  
Maria Helena Fernandes ◽  
Francisco Vale

(1) Background: The etiology of orofacial cleft (OC) is not completely known but several genetic and environmental risk factors have been identified. Moreover, a knowledge gap still persists regarding neonatal characteristics. This study evaluated the effect of parental age and mothers’ body mass index on the risk of having an OC child, in a matched year and sex group (cleft/healthy control). Additionally, birth data were analyzed between groups. (2) Methods: 266 individuals born between 1995 to 2015 were evaluated: 133 OC individuals (85 males/48 females) and 133 control (85 males/48 females). A logistic model was used for the independent variables. ANOVA or Kruskal-Wallis tests were used for comparison between the OC phenotypes. (3) Results: Regarding statistically significant parental related factors, the probability of having a cleft child decreases for each maternal year increase (odds ratio = 0.903) and increases for each body mass index unit (kg/m2) increase (odds ratio = 1.14). On the child data birth, for each mass unit (kg) increase, the probability of having a cleft child decrease (odds ratio = 0.435). (4) Conclusions: In this study, only maternal body mass index and maternal age found statistical differences in the risk of having a cleft child. In the children’s initial data, the cleft group found a higher risk of having a lower birth weight but no relation was found regarding length and head circumference.


2021 ◽  
Author(s):  
Feiyue Sun ◽  
Wenlong Wu

Abstract The study of rockburst criterion is the key to predict whether rockburst occurs or not. First of all, based on the energy principle and taking the rock strength and overall failure criterion as the benchmark, the rockburst proneness criterion of rock mass unit under compression and tension was established. The criterion took into account the integrity factors, mechanical factors, brittleness factors and energy storage factors in the process of rockburst inoculation, and three rockburst classification thresholds (2, 11 and 110) for four grades of none, weak, moderate and severe rockburst were proposed. Second, Taking the typical rockburst disaster as examples, the rationality of the existing classical rockburst criterions and the rockburst proneness criterion proposed in this paper were tested, and the results showed that this criterion had good engineering applicability. Finally, the numerical simulation analysis of rockburst disaster in 2# diversion tunnel of Jinping II hydropower station was carried out by using this criterion. The results were basically consistent with the actual situation, which verified the accuracy and effectiveness of the rockburst proneness criterion proposed in this paper. The research results can provide reference for the evaluation and prediction of rockburst disaster in deep underground engineering.


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