Development of a New High Performance Cold Mix Asphalt

In recent years, global climate change and energy shortages have become serious issues of common concern internationally. The majority of roads and highways are paved using hot mix asphalt (HMA) technology. The manufacture of hot mix asphalt is a key source of energy consumption, greenhouse gas emissions and air pollution. As such, efforts have been made to develop sustainable techniques to reduce energy consumption by lowering manufacturing temperatures, which in turn, will reduce CO2 emissions and subsequent negative impacts on the environment. Cold bitumen emulsion mixtures (CBEMs) are an excellent alternative to traditional HMA, from both an economic and environmental point of views. However, there are certain issues related to the mechanical properties of CBEMs that make them inferior to HMA, limiting their use to low traffic roads, reinstatement works and footways. Accordingly, the development of a CBEM with high early strength and minimal curing time is of increasing interest to researchers in the asphalt industry. The aim of this research work was to develop a new, high performance and environmentally friendly, surface course, cold bitumen emulsion mixture for heavily trafficked roads. This aim has been achieved by i) addressing the longstanding problems associated with conventional bitumen emulsions, namely large and non-uniform distribution of bitumen droplets within the emulsion, and ii) reducing the long curing time of CBEMs by replacing conventional limestone filler (LF) with a new secondary cementitious filler made primarily from waste materials. Ultrasound technology was used to reduce the size of the bitumen droplets through the cavitation phenomenon. A cationic bitumen emulsion (C50B4) was treated using ultrasound apparatus, over different periods of time. The results revealed an 85% reduction in mean droplet size (D50), under 7 minutes sonication treatment compared to the untreated sample. Reductions in D90 and D10 were 90% and 86%, respectively, in comparison to the untreated sample. The particle size distribution (PSD) curve shows more uniformly distributed droplets closer to the mean values, in comparison to the untreated emulsion. The viscosity of the 7minute sonicated bitumen emulsion decreased by 28%, compared to the untreated emulsion. CBEM-LF, made with 7-minute sonicated bitumen emulsion, showed an enhancement in indirect tensile stiffness modulus (ITSM) at 3 days curing by approximately 70%, compared with the same mixture containing conventional bitumen emulsion. To eliminate the long curing time required by CBEMs, a new cementitious filler was developed from waste materials and used as a substitute to conventional LF. The new alkali ternary blended filler, ATBF2, comprises ordinary Portland cement (OPC), a high volume of waste sewage sludge fly ash (SSFA) and calcium carbide residue (CCR). A waste calcium hydroxide solution was used as a replacement for the aggregate pre-wetting water in the CBEM. CCR played a vital role activating the SSFA by breaking the glassy phases of the non-amorphous silica in the SSFA, while the waste calcium hydroxide solution increased the hydraulic reactivity of the cementitious components. Scanning electron microscopy (SEM) and x-ray diffraction (XRD) were used to investigate the development of hydration products in the new CBEM. Concentrations of heavy metals in the samples incorporating ATBF2, were observed to be less than the regulatory levels determined for hazardous materials. The mechanical properties of the novel CBEM incorporating both the sonicated bitumen emulsion and ATBF2 filler, were investigated in terms of ITSM at different curing times, rutting resistance, fatigue resistance, water damage resistance and age hardening. The said mixture offers a substantial improvement in stiffness modulus, compared to HMA and CBEM containing conventional emulsion and LF. The ITSM for the newly developed CBEM at 3 days of age, increased by approximately 19 times that of the conventional cold mixture, and almost 2.5 times that of traditional 100/150 HMA. The new mixture also displayed considerably higher resistance to permanent deformation in comparison to the reference cold and hot asphalt mixtures, demonstrating its potential for use in heavily trafficked roads. Resistance to fatigue was significantly enhanced by the use of both ATBF2 and the modified emulsion in the CBEM, compared to conventional cold and hot mixtures. This mixture is more durable because of improvements in resistance to water damage and enhanced long term ageing performance. This improvement has been achieved by the presence of smaller bitumen droplets that provide more bitumen surface area and even coating of aggregate particles. This helps form a cohesive mixture working in parallel with the hydration products which resulted from the hydration process of the cementitious filler in the presence of water within the bitumen-water solution

Використання нетрадиційної сировини у технології варених ковбасних виробів функціонального призначення

In modern conditions of meat production, one of the priorities of the meat processing industry is the production of products with improved consumer properties. To perform this task, it is necessary to include in the industrial circulation of physiologically functional ingredients of plant origin, which will provide the body with nutrients and expand the range of functional foods. The paper covers the issues of partial replacement of raw materials of animal origin with germinated sea-buckthorn seeds (GSBS) flour as a functional ingredient in the production of sausages. The chemical and vitamin composition of the physiologically functional ingredient has been studied. Three experimental recipes for sausages from GSBS flour has been developed. The positive influence of GSBS flour on functional-technological and physical-chemical properties of the received forcemeat is proved. Organoleptic parameters of sausages from GSBS flour are determined. The use of GSBS flour as a functional ingredient in the technology of sausages affects the appearance, taste, smell. It is established that the increase in the amount of GSBS flour introduction leads to an increase in pH by 0.4–0.8 % and finished products by 6.8 %. The improvement of functional and technological properties of experimental minced meat of sausages based on the use of GSBS flour is proved. The optimal amount of replacement of the main raw material with a physiologically functional ingredient, which is characteristic of the experimental sample № 2. The changes in the qualitative characteristics of the developed sample of sausages, which where within the regulatory requirements. The addition of 10 % GSBS flour to the minced meat of sausages leads to a slight increase in protein with a significant reduction in lipid content by 4.4 % in the finished product. As a result, the caloric content of Altaiska functional sausage is reduced by 13.2 % compared to traditional products. Production of such products will allow to expand the domestic range of functional products. Consumption of such sausages allows to consider them as foodstuff with essentially new functional properties which would correspond to modern requirements concerning food.В сучасних умовах виробництва м’ясної продукції одним із пріоритетних завдань м’ясопереробної галузі є випуск продукції з поліпшеними споживчими властивостями. Для виконання цього завдання необхідно максимально включити в промисловий обіг фізіологічно функціональні інгредієнти рослинного походження, що дасть можливість забезпечити організм поживними речовинами та розширити асортимент функціональних продуктів харчування. У роботі висвітлені питання часткової заміни сировини тваринного походження на борошно пророщеного насіння обліпихи (БПНО) як функціонального інгредієнта при виробництві ковбасних виробів. Досліджено хімічний і вітамінний склад фізіологічно функціонального інгредієнта. Розроблено три дослідні рецептури ковбасних виробів із БПНО. Доведено позитивний вплив БПНО на функціонально-технологічні й фізико-хімічні властивості одержаного фаршу. Визначено органолептичні показники ковбасних виробів з БПНО. Застосування БПНО як функціонального інгредієнта в технології ковбасних виробів впливає на зовнішній вигляд, смак, запах. Встановлено, що збільшення кількості введення БПНО призводить до збільшення рН на 0,4–0,8 % та виходу продукції на 6,8 %. Доведено покращення функціонально-технологічних властивостей дослідних фаршів ковбасних виробів на основі використання БПНО. Встановлено оптимальну кількість заміни основної сировини на фізіологічно функціональний інгредієнт, який характерний для дослідного зразка № 2. Досліджено зміни якісних характеристик розробленого зразка ковбасних виробів, які перебувають у межах нормативних вимог. Введення 10 % БПНО в фарш ковбасних виробів призводить до незначного збільшення білка при значному зменшенні вмісту ліпідів на 4,4 % в готовому продукті. В результаті знижується калорійність вареної ковбаси функціонального призначення “Алтайська” на 13,2 % порівняно з традиційними виробами. Виробництво такої продукції дозволить розширити вітчизняний асортимент виробів функціонального призначення. Споживання таких ковбасних виробів дозволяє вважати їх продуктами харчування з істотно новими функціональними властивостями, які відповідали б сучасним вимогам щодо харчування

A review on the classifications and applications of solar photovoltaic technology

Our aim of this work is to present a review of solar photovoltaic (PV) systems and technologies. The principle of functioning of a PV system and its major components are first discussed. The types of PV systems are described regarding the connections and characteristics of each type. PV technology generations are demonstrated, including the types, properties, advantages and barriers of each generation. It was revealed that the first generation is the oldest among the three PV generations and the most commonly utilized due to its high efficiency in spite the high cost and complex fabrication process of silicon; the second generation is characterized by its low efficiency and cost and flexibility compared to other generations; and the third generation is not commercially proven yet in spite the fact that it has the highest efficiency and relatively low cost, its raw materials are easy to find and its fabrication process is easier than the other generations. It was shown that the target of all the conducted studies is to study the PV technology to enhance its performance and optimize the benefit from solar energy by reducing conventional energy dependence, mitigating CO2 emissions and promote the economic performance

Performance comparison of two solar cooking storage pots combined with wonderbag slow cookers for off-sunshine cooking

Two similar storage cooking pots are experimentally evaluated and compared during solar cooking and storage off-sunshine cooking periods. One storage pot has sunflower oil as the sensible heat storage material, while the other has erythritol as the phase change material (PCM). To test their thermal performance during off-sunshine periods, the two pots are placed in insulated wonderbag slow cookers. Water and sunflower oil are used as the cooking fluids in the experimental tests. The sunflower oil cooking pot shows better performance during the solar cooking periods since it shows shorter cooking times (1.8–5.6 h) compared to the erythritol PCM pot (3.8–6.6 h). The sunflower oil pot also attains higher maximum storage temperatures (124–145 °C) compared to the erythritol PCM pot (118–140 °C). Storage efficiencies for the sunflower oil pot (3.0–7.1%) are also greater than those of the PCM pot (2.5–3.7%). During the storage cooking periods, the erythritol based phase change material cooking pot shows better performance as evidenced by the lower temperature drops (0.1–9.7 °C) from the maximum cooking temperatures compared to 8.3 to 34 °C for the sunflower oil pot. The heat utilisation efficiencies for the erythritol pot (4.8–14.3%) are also greater compared to the sunflower oil pot (3.7–6%)

Systèmes hybrides photovoltaïque / thermique / thermoélectrique à concentrateur parabolique : modélisation thermique, analyse paramétrique et études de cas

In recent years, solar energy has gained crucial attention from researchers due to its great potential to compensate for energy deficiencies. Solar energy research and studies aim not only to optimize existing solar energy systems, but also to combine them to obtain hybrid solar energy systems that produce thermal energy and generate electric power simultaneously. In this context, the aim of the present doctoral study is to extensively examine the literature related to solar energy studies, particularly hybrid systems, but also to suggest new hybrid systems and to deeply analyze other existing systems using appropriate thermal modeling as well as parametric analyzes and case studies. It all started with a new methodology to drive a thermal model for theParabolic Trough Photovoltaic Thermal system(PTPVT). A parametric analysis is performed to study the performance of the system and the influence of several parameters on it. Case studies are implemented in three different countries to study the effect of climatic conditions on system performance. In addition, economic and environmental analyzes are carried out to calculate the payback period of the system and the amount of CO2 emissions reduced in the three countries. In addition, a Parabolic Trough PhotovoltaicThermal Thermoelectric system (PTPVT-TE) is demonstrated where thermal modeling is developed using a new methodology and case studies are performed on three different countries with economic and environmental analyzes.Au cours des dernières années, l'énergie solaire a retenu une attention cruciale de la part des chercheurs en raison de son grand potentiel à compenser les carences de production d'énergie. Les recherches et études menées sur l'énergie solaire visent non seulement à optimiser les systèmes d'énergie solaire existants, mais aussi à les combiner pour obtenir des systèmes d'énergie solaire hybrides qui permettent de produire de l'énergie thermique et de générer de l'énergie électrique simultanément. Dans ce contexte, le but de cette étude est d’examiner de manière extensive la littérature liée aux études d’énergie solaire, particulièrement les systèmes hybrides, mais aussi de suggérer de nouveaux systèmes hybrides et d’analyser d’autres systèmes existants en utilisant des modélisations thermiques appropriées ainsi que des analyses paramétriques et études de cas.En premier lieu, nous présentons une nouvelle méthodologie pour établir un modèle photovoltaïque / thermique à concentrateur parabolique (PTPVT « Parabolic Trough Photovoltaic/Thermal »). Une analyse paramétrique est réalisée pour étudier les performances du système et l'influence de plusieurs paramètres. Des études de cas sont mises en œuvre dans trois pays différents pour étudier l'effet des conditions climatiques sur les performances du système. En outre, des analyses économiques et environnementales sont menées pour calculer la période de retour sur investissement du système et la réduction des émissions de CO2 dans les trois pays.De plus, un système photovoltaïque / thermique / thermoélectrique à concentrateur parabolique(PTPVT-TE « Parabolic Trough Photovoltaic Thermal Thermoelectric ») est décrit, dans lequel une modélisation thermique est développée à l'aide d'une nouvelle méthodologie et des études de cas sont réalisées sur trois pays différents avec des analyses économiques et environnementales

Mob Programming para escrever código com alta complexidade e trabalho remoto

Nowadays, the world relies on software, and the citizens of this modern world demand good quality software. Moreover, their needs change constantly. Hence, they require new software or new versions of existing ones that correctly solve their problems. Additionally, software development is not just about the cost or quality of software but also about the people who work to produce software. The motivation is to find better ways to organize the work of the programmers to develop quality software in a productive way suitable to their current context. The COVID-19 pandemic impacts the work environment and obligates people to work remotely. Furthermore, the software developed is increasingly complex. Thus, it emerges in society\'s need for software development techniques to create complex software with quality and permit software developers to work remotely. Creating reliable, stable, easy maintenance software is to its quality. This research is about an emerging, popular, and current practice to increase the quality of software development, learning, and programmer satisfaction: Mob Programming. The idea of Mob Programming is the entire team developing software as a group together around a computer and not as an isolated task. The research strategy is a Grounded Theory about Mob Programming. It is observed in practice its benefits in high complexity software development and remote work. Interviews, questionnaires, observations, and source code analysis produce raw data about these observations. Thence is analyzed these data using open code, constant comparison method, core category, selective coding, memoing, sorting, and theoretical coding following the Grounded Theory research method to serve as a recommendation for software developers with suggestions about team roles and practices related to how to use Mob Programming on complex tasks and remote work.Hoje em dia, o mundo depende de software e os cidadãos deste mundo moderno exigem software de boa qualidade. Além disso, suas necessidades mudam constantemente. Assim, eles demandam um novo software ou novas versões dos existentes que resolvam corretamente seus problemas. Adicionalmente é correto afirmar que o desenvolvimento de software não envolve apenas o custo ou a qualidade do software, mas também as pessoas que trabalham para produzi-lo. A motivação é encontrar melhores formas de organizar o trabalho dos programadores para desenvolver software de qualidade de forma produtiva e adequada ao seu contexto atual. A pandemia COVID-19 impacta o ambiente de trabalho e obriga as pessoas a trabalharem remotamente. Ademais, o software desenvolvido está cada vez mais complexo. Consequentemente, surge na sociedade a necessidade de técnicas para o desenvolvimento de software complexo com qualidade e que permitam aos desenvolvedores de software trabalharem remotamente. A criação de um software confiável, estável e de fácil manutenção depende de sua qualidade. Esta pesquisa é sobre uma prática emergente, popular e atual para aumentar a qualidade no desenvolvimento de software, aprendizagem e satisfação dos programadores: Mob Programming. A ideia do Mob Programming é toda a equipe desenvolvendo software como um grupo em torno de um computador e não como uma tarefa isolada. A estratégia de pesquisa é produzir uma Teoria Fundamentada nos Dados observados sobre o Mob Programming. Foram observados na prática os benefícios do Mob Programming no desenvolvimento de software de alta complexidade e trabalho remoto. Entrevistas, questionários, observações e análise do código-fonte produzem dados brutos sobre essas observações. Então, esses dados foram analisados por meio da codificação aberta, análise comparativa constante, categorização, codificação seletiva, elaboração de memorandos, ordenação e, codificação teórica seguindo o método de pesquisa Teoria Fundamentada nos Dados para servir como recomendação para desenvolvedores de software com sugestões sobre funções dos membros da equipe e práticas relacionadas com a forma de usar o Mob Programming em tarefas complexas e trabalho remoto

Hybrid Photovoltaic / Parabolic trough thermal / Thermoelectric systems : thermal modeling, parametric analysis, and case studies

Au cours des dernières années, l'énergie solaire a retenu une attention cruciale de la part des chercheurs en raison de son grand potentiel à compenser les carences de production d'énergie. Les recherches et études menées sur l'énergie solaire visent non seulement à optimiser les systèmes d'énergie solaire existants, mais aussi à les combiner pour obtenir des systèmes d'énergie solaire hybrides qui permettent de produire de l'énergie thermique et de générer de l'énergie électrique simultanément. Dans ce contexte, le but de cette étude est d’examiner de manière extensive la littérature liée aux études d’énergie solaire, particulièrement les systèmes hybrides, mais aussi de suggérer de nouveaux systèmes hybrides et d’analyser d’autres systèmes existants en utilisant des modélisations thermiques appropriées ainsi que des analyses paramétriques et études de cas.En premier lieu, nous présentons une nouvelle méthodologie pour établir un modèle photovoltaïque / thermique à concentrateur parabolique (PTPVT « Parabolic Trough Photovoltaic/Thermal »). Une analyse paramétrique est réalisée pour étudier les performances du système et l'influence de plusieurs paramètres. Des études de cas sont mises en œuvre dans trois pays différents pour étudier l'effet des conditions climatiques sur les performances du système. En outre, des analyses économiques et environnementales sont menées pour calculer la période de retour sur investissement du système et la réduction des émissions de CO2 dans les trois pays.De plus, un système photovoltaïque / thermique / thermoélectrique à concentrateur parabolique(PTPVT-TE « Parabolic Trough Photovoltaic Thermal Thermoelectric ») est décrit, dans lequel une modélisation thermique est développée à l'aide d'une nouvelle méthodologie et des études de cas sont réalisées sur trois pays différents avec des analyses économiques et environnementales.In recent years, solar energy has gained crucial attention from researchers due to its great potential to compensate for energy deficiencies. Solar energy research and studies aim not only to optimize existing solar energy systems, but also to combine them to obtain hybrid solar energy systems that produce thermal energy and generate electric power simultaneously. In this context, the aim of the present doctoral study is to extensively examine the literature related to solar energy studies, particularly hybrid systems, but also to suggest new hybrid systems and to deeply analyze other existing systems using appropriate thermal modeling as well as parametric analyzes and case studies. It all started with a new methodology to drive a thermal model for theParabolic Trough Photovoltaic Thermal system(PTPVT). A parametric analysis is performed to study the performance of the system and the influence of several parameters on it. Case studies are implemented in three different countries to study the effect of climatic conditions on system performance. In addition, economic and environmental analyzes are carried out to calculate the payback period of the system and the amount of CO2 emissions reduced in the three countries. In addition, a Parabolic Trough PhotovoltaicThermal Thermoelectric system (PTPVT-TE) is demonstrated where thermal modeling is developed using a new methodology and case studies are performed on three different countries with economic and environmental analyzes

Parabolic trough photovoltaic thermoelectric hybrid system: Thermal modeling, case studies and economic and environmental analyses

International audienc

DEVELOPMENT OF A PREMIUM COLD MIX ASPHALT

Cold mix asphalt produced using conventional emulsion and limestone filler has three main disadvantages, namely low early strength due to high amount of water within the mix, long curing time ranging from 2-24 months and high air voids content. In this study, the effect of a novel technology for producing high-quality cold mix asphalt using modified bitumen emulsion has been investigated in terms of indirect tensile stiffness modulus. the effect of a novel technology for homogenizing a bitumen emulsion on its viscosity, particle size and particle size distribution has been investigated. Ultrasound technology has been used to reduce the viscosity and the size of the bitumen droplets. Different samples of cationic bitumen emulsion (C50B4) have been prepared with different treatment durations (0, 5, 7, 10, 12.5, 15, 30, 45 and 60) min. The results have shown a reduction in the viscosity of the bitumen emulsion at treatment times from 5-15 min. The viscosity has been decreased by 28% after 10 min treatment for the emulsion compared to the untreated sample. This reduction indicated a uniform droplet size distribution. In addition, the particle size measurements revealed that the 7 min treatment showed a significant reduction in the D50, which was 84.5%, D10, was 85.89%, and D90 was 90.28% compared to the untreated bitumen emulsion. The results reported contains a comparison between the viscosity of the emulsions, and the indirect tensile stiffness modulus of a control conventional cold mix asphalt and the new high quality cold mix asphalt with low viscosity. Interestingly, the reduction of the 28% in the viscosity of the new emulsion causes an improvement of the indirect tensile stiffness modulus to 216%, which indicates an outstanding achievement

Comparative study of the effect of beclomethasone inhaler versus topical lidocaine on the attenuation of post-intubation throat symptoms in pregnant patients undergoing cesarean section

Background: Sore throat, cough and hoarseness are common problems after endotracheal general anesthesia. They may be very distressing to the patient, they may have many unwanted sequelae .Various preparations of lidocaine, and corticosteroids have been frequently used to prevent or attenuate these complications. Aim: To compare between beclomethasone inhaler and topical lidocaine lubricant for the reduction in incidence of post-operative sore throat, cough and hoarseness of voice. Patients and method: Ninety pregnant women (18–35 years of age) with I undergoing elective cesarean section were allocated into 3 groups of 30 patients in each as follows (group A: Topical lidocaine, group B: Beclomethasone inhaler , group C: Control). The endotracheal tubes in-group (A) were lubricated with lidocaine gel 5%. Group (B) patients receive 2 puffs (100 ug) of beclomethasone inhaler.In the group C patients, no medication was administered or applied. Patients were interviewed by a blind investigator for sore throat, cough and hoarseness (as none, mild, moderate, or severe), at 2 h, 6 h,12 h. and 24 h. after full recovery. Results: Beclomethasone inhaler significantly decreases the incidence and severity of sore throat in comparison with lidocaine lubricant and control groups especially in the first 6 hours postoperatively (P-value < 0.05). &nbsp