Hasil untuk "Environmental engineering"

S. Amiri, H. Shokrollahi

G. Cheraghian, A. C. Falchetto, Zhanping You et al.

Abstract The purpose of the current review is to give an insight into various Warm Mix Asphalt (WMA) techniques in pavement engineering. The idea is to provide a comprehensive overview of this technology that may serve as a basis for engineers and practitioners to structure the entire processes, associated with the design and construction of roads, under healthier and safety-oriented working conditions while following an environmentally friendly conscious approach. This manuscript provides an up-to-date review of WMA technologies. The paper also presents and compares several studies on the most common additives, mix design and environmental benefits of this production method. Also, this review discusses the improvement in physical, mechanical properties and durability of pavement designed with WMA mixtures.

N. Megahed, Ehab Ghoneim

To effectively reduce the spread of SARS-CoV-2, it is crucial to highlight the effectiveness of building design strategies in mitigating threats to occupants. The ongoing pandemic research and actions focus on how poor Indoor Air Quality (IAQ) amplifies the effects of airborne viruses. This review aims to draw architects' attention toward the high risk of airborne transmission of diseases by providing the latest updates and solutions to understand better the environmental and health issues associated with COVID-19. Based on the complexity of the problem and the need for interdisciplinary research, this study presents a conceptual model that addresses the integration of engineering controls, design strategies and, air disinfection techniques required to achieve a better IAQ.

Qinglin Yang, Yang He, Lukai Zhou et al.

Driven by the combined effects of global warming and the urban heat island (UHI) effect, building energy consumption has been rising steadily in recent years. The photovoltaic-cool roof (PVCR) system has emerged as an effective solution for urban energy conservation and carbon reduction. However, existing research on the energy-saving benefits of PVCR remains relatively limited, and none of these studies have considered the interaction between photovoltaic modules and high-reflectivity roofs (also called cool roof, CR). Therefore, field experiments were conducted to compare the thermal performance of the PVCR system against that of three conventional roof configurations, including photovoltaic roof (PVR), asphalt roof (AR), and CR. The results demonstrate that the PVCR system achieves a remarkable daytime cooling effect, with a maximum temperature reduction of 29 °C compared to the AR system, and maintains lower temperature fluctuations throughout the entire day. In addition, the findings reveal that the photovoltaic modules exhibit a lower average temperature when installed on the cool roof, with a temperature decrease of 0.15 °C relative to the asphalt roof. A numerical model incorporating the photothermal interaction between a high-reflectivity surface and PV modules was developed and validated with experimental data. The numerical model considers the interactions between the photovoltaic (PV) modules and the high reflectivity surface, including shortwave radiation reflection, longwave radiative exchange, and convective heat transfer. The sensitivity analysis indicates that a change in the spacing and height of the PV arrays from 0.3 m to 0.5 m increases the relative energy-saving efficiency of the system. The conclusions drawn in this paper can provide a reference for the application of the PVCR system in hot-summer and cold-winter areas.

Ekundayo A. ADESINA, Oluibukun G. AJAYI, Joseph O. ODUMOSU et al.

Traditional urban growth models often decouple land-use change from its climatic consequences, creating planning blind spots. This study introduces a globally transferable Dynamic Suitability-Weighted CA-Markov (DSW-CA-Markov) framework that, for the first time, integrates Land Surface Temperature (LST) trends as dynamic suitability factors within Cellular Automata transition rules, enabling bidirectional urban-thermal feedback simulation. We develop and validate this framework using multi-temporal Landsat data (2010, 2015, 2020) from Abuja, Nigeria, then project integrated urban-thermal patterns to 2030. Our primary innovation is a dynamic feedback mechanism where pixel-level LST change rates are embedded as evolving suitability factors within CA transition rules, moving beyond static suitability mapping or post-hoc thermal correlation. Results reveal a 157.29% built-up increase (2010-2020) with LST rises of 3.6 °C, and projected continued expansion with amplified UHI effects. The DSW-CA-Markov framework demonstrates superior capability in simulating coupled urban-thermal dynamics compared to conventional CA-Markov approaches (Kappa improvement: 0.08; thermal : 0.73 vs. 0.65). This study provides both a novel methodological template for climate-responsive urban modelling and crucial insights for sustainable planning in fast-growing cities globally.

N. Wildmann, L. Györy

<p>This study demonstrates the feasibility of measuring temperature variance and heat flux with self-calibrated fine-wire platinum resistance thermometers (FWPRT) on multicopter drones. The sensors are especially designed for light weight, fast response-times and to be carried on miniature drones for turbulence measurements. A significant improvement was found in vertical profiling of temperature gradients compared to slower solid-state sensors, demonstrating reduced hysteresis between ascent and descent phases and accurate representation of strong gradients. More than 100 single flights with the sensors attached to drones of the SWUF-3D fleet were carried out in vicinity to a meteorological mast array at the WiValdi wind energy research park in Northern Germany. The comparison to sonic anemometers shows that temperature variance can be accurately measured within the background flow variability. The same applies for heat flux, which was measured for the first time with multicopter UAS and the eddy covariance method without external sensors. Heat flux is a crucial parameter to understand the energy balance of the atmospheric boundary layer and turbulent mixing. An uncertainty below 50 W m<span class="inline-formula">⁻²</span> was determined with the constraint that only low to moderate wind speed conditions (3–8 m s<span class="inline-formula">⁻¹</span>) could be used to allow vertical wind speed measurements with the current algorithm. The results indicate that the temperature sensors are suited for heat flux measurements, but further improvements are necessary with regard to vertical wind speed estimates to decrease the overall uncertainty.</p>

Monika Czop, Joanna Wyczarska-Kokot, Joanna Kalka et al.

A municipal wastewater treatment plant is a complex system of technological devices and facilities designed to remove pollutants from wastewater. The operation of such plants generates a waste stream that can be classified into three types: screenings (code 19 08 01), sand trap contents (code 19 08 02), and stabilized municipal sewage sludge (code 19 08 05). Each generated waste must be managed in accordance with the applicable law. In the context of new business models within the closed-loop economy, wastewater treatment plants are viewed as a resource rich resource that can be used to reclamate degraded lands. The purpose of the study was to evaluate the physicochemical parameters of the waste, which could form the basis for the preparation of soil-forming material. The input material considered was excess digester sludge after the stabilization process, sand from the sand traps, and sand after cleaning the wastewater network. The tested sludge contained 35 % organic substances, 12 % organic carbon, 1.8 % total nitrogen, and 0.24 % potassium. The sand contained about 1 % organic matter, 1.8 % organic carbon, 0.5 % total nitrogen, and 0.02 % potassium. Sand and sludge were prepared in the following mixtures: 1:1, 1:2, 2:1. These mixtures were then assessed for their suitability in the reclamation of degraded areas.

Hošták Peter, Šooš Ľubomír

Article describes the development of an application for generating 3D models of bearings used in the design of machine tool spindles. The models are created in CATIA v5 software using parametric modelling, which allows for easy modification of bearing dimensions and types according to the selected type from the database. The application has two main parts: spindle design and the generation of bearings. In the future, we plan to develop other headstock components such as spindle front ends, seals, clamping and other elements in this way. The user interface is simple and designed for fast work. The software has a modular structure and can be easily expanded and modified.

M. Alvesa, J. F. Manoa

B. Rose, Ding Huang, Zi-Huai Zhang et al.

In search of the right diamond defect Certain defects in diamond are among the most promising physical implementations of qubits, the building blocks of quantum computers. However, identifying a defect with balanced properties is tricky: Nitrogen vacancy centers have a long lifetime but comparatively poor optical properties, whereas negatively charged silicon vacancy centers have the opposite characteristics. Rose et al. used careful materials engineering to stabilize the neutral charge state of silicon vacancy centers and found that they combine long coherence times with excellent optical properties. Science, this issue p. 60 The neutral charge state of silicon vacancy centers in diamond shows promising quantum information properties. Engineering coherent systems is a central goal of quantum science. Color centers in diamond are a promising approach, with the potential to combine the coherence of atoms with the scalability of a solid-state platform. We report a color center that shows insensitivity to environmental decoherence caused by phonons and electric field noise: the neutral charge state of silicon vacancy (SiV0). Through careful materials engineering, we achieved >80% conversion of implanted silicon to SiV0. SiV0 exhibits spin-lattice relaxation times approaching 1 minute and coherence times approaching 1 second. Its optical properties are very favorable, with ~90% of its emission into the zero-phonon line and near–transform-limited optical linewidths. These combined properties make SiV0 a promising defect for quantum network applications.

Ha-won Song, V. Saraswathy

Reinforced concrete structures have the potential to be very durable and capable of withstanding a variety of adverse environmental conditions. However, failures in the structures do still occur as a result of premature reinforcement corrosion. The maintenance and repair of bridges and buildings for their safety requires effective inspection and monitoring techniques for assessing the reinforcement corrosion. Engineers need better techniques for assessing the condition of the structure when the maintenance or repair is required. These methods need to be able to identify any possible durability problems within structures before they become serious. This paper reviews all the electrochemical and nondestructive techniques from the point of view of corrosion assessment and their applications to bridges, buildings and other civil engineering structures.

شهریار مهدوی, مهسا موسوی, امین ترنجیان

هدف این پژوهش، بررسی کارایی جاذب‌های بیدلیت و گرافن در حذف رنگزای کنگورد از آب به منظور بهبود فرآیندهای تصفیه آب است. رنگزای کنگورد به دلیل خطرات زیست‌محیطی و بهداشتی، نیازمند حذف مؤثر از منابع آبی است. در این پژوهش، جاذب‌های بیدلیت و گرافن با آنالیزهای دستگاهی همانندSEM, FTIR, EDAX, XRD  و پتانسیل زتا  بررسی می‌شود. اثر عواملی نظیر غلظت جاذب، pH، دما و زمان تماس بر روی جذب رنگ مورد آزمایش قرار گرفتند. نتایج نشان داد که جاذب گرافن با راندمان 87.66 درصد در دمای 50 درجه سانتی‌گراد و 9pH= و جاذب بیدلیت با راندمان 80.78 درصد در دمای 20 درجه سانتی‌گراد و 6pH= بهترین عملکرد را در حذف کنگورد از آب داشتند. مدل‌های سینتیکی شبه مرتبه دوم و ایزوترم فروندلیچ به ترتیب بهترین برازش را با داده‌های آزمایشگاهی نشان دادند. همچنین، بررسی متغیرهای ترمودینامیکی نشان داد که فرآیند جذب در هر دو جاذب گرافن و بیدلیت خودبه‌خودی اما واکنش در بیدلیت گرمازا و گرافن گرماگیر بود. ضمنا ظرفیت جذب برای گرافن و بیدلیت به ترتیب 5.47 و 6.73 میلی‌گرم بر گرم به‌دست آمد. نتایج آزمایش‌های واجذب نشان دادند به ویژه در غلظت‌های پایین رنگزا میزان بازیافت بالا است. بنابراین با توجه کارایی بالای جاذب‌های بیدلیت و گرافن در حذف رنگزای کنگورد و امکان استفاده مجدد از آن‌ها در فرآیندهای تصفیه آب، پژوهش‌های بیشتر بر روی این ترکیبات توصیه می‌شود.

K. Ahmed

Hassan Saad Jasim, Zainab Z. Ismail Ismail

This study investigates the potential of biogas recovery from used engine oil (UEO) by co-digestion with animals’ manure, including cow dung (CD), poultry manure (PM), and cattle manure (CM). The experimental work was carried out in anaerobic biodigesters at mesophilic conditions (37°C). Two groups of biodigesters were prepared. Each group consisted of 4 digesters. UEO was the main component in the first group of biodigesters with and without inoculum, whereby a mix of UEO and petroleum refinery oily sludge (ROS) was the component in the second group of biodigesters. The results revealed that for UEO-based biodigesters, maximum biogas production was 0.98, 1.23, 1.93, and 0 ml/g VS from UEO±CD, UEO±CM, UEO±PM, and UEO, respectively, whereby, for the UEO=ROS-based biodigesters, maximum biogas production was 3.49, 2.47, 3.64 and 2.44 ml/g VS from UEO+ROS±CD, UEO+ROS±CM, UEO+ROS±PM, and UEO+ROS, respectively. These results indicated that UEO was not feasible and efficient for biogas recovery since biogas production was very low in the first group of biodigesters compared to its recovery in the second group. A modified Gompertz model was applied to study the kinetics of the bio-digestion process. Measured and predicted values of biogas generation were fitted well with determination coefficients higher than 0.92.  

Shixiong Liao, Kun Ma, Lei Wu et al.

The research and development of new building materials such as phosphorous building gypsum is crucial to promote the utilisation of phosphogypsum resources by improving their value. This study developed a new type of shape-stabilised energy storage phosphorus building gypsum aggregate (ES-PBGA). The mechanical and thermal properties of ES-PBGA with Paraffin were investigated. The results indicate that the matrix of ES-PBGA had a good microstructure, and the optimal paraffin-embedding rate of ES-PBGA was 31.08%. The phase transition temperature and enthalpy of the endothermic and exothermic stages were 17.6 and 27.14 ℃, and 33.02 and 31.62 J/g, respectively. The cylinder pressure strength of ES-PBGA with paraffin (31.08%) was 4.32 MPa, which meets the requirements of artificial aggregate application. To verify the practicability of ES-PBGA, energy storage lightweight aggregate concrete was prepared with 0%, 25%, 50%, and 100% ES-PBGA to replace the lightweight shale ceramsite. The results show that ES-PBGA can improve the interface transition zone between cement-based materials and energy storage aggregates, thereby improving the strength, and has a relatively suitable thermal conductivity, thermal diffusion coefficient, and specific heat capacity. Furthermore, it is also a type of low-carbon energy storage aggregate, and its application in the field of energy storage composite building materials is a relatively new concept.

E.R. Akhabue, U.P. Eyibio, K.S. Ukanwa et al.

This study converted the hybridized oil produced from the blend of seed oil and animal wastes fat to biodiesel using a developed catalyst from palm kernel empty burnt bunch ash (PKPKEBBA). The hybridized oil was obtained via specific gravity method and the properties of the oils were determined. The developed catalyst was characterized using SEM, FTIR, XRF-FT, BET-adsorption, and qualitative analysis. Process optimization was carried out using RSM-CCD and ANN-GA with references to four variables namely: reaction period, catalyst conc., reaction temperature, and E-OH/OMR, respectively. The kinetics and thermodynamic parameters of the transesterification reaction was also carried out. The developed catalyst was recycled and reused, while the quality of the biodiesel was examined with a view to determine its potential to replace conventional diesel. Results showed low viscous and acid value of the hybridized oil which was obtained in a single stage conversion. The mix ratio of the hybridized oil was found to be 33:34:33 with respect to pumpkin seed oil, goat fat, and poultry waste fat. The developed heterogeneous catalyst contained CaCO3 as the major element found in the PKEBBA. Process optimization showed that ANN-GA gave a better optimum validated yield of 99.20% (wt./wt.) than RSM-CCD of 98.44% (wt./wt.). Considered design variables were mutually significant at p-value<0.0001. The rate equation constant was 0.0177 min−1, while the thermodynamic parameters at highest temperature (348 K) were ΔGr= 101.38 KJ/mol, ΔHr=-5.82 × 10−5 KJ/mol, and ΔSr= −291.32 KJ/mol. K. The strength of catalyst tested via reusability test showed catalyst reusability test was altered at 7 cycles. The produced biodiesel have fuel properties similar to conventional diesel. The study concluded that the hybridization of oils for biodiesel conversion is viable.

Muhammad Naeem, Saba Manzoor, Mashhud-Ul-Hasan Abid et al.

With the increasing world population, demand for industrialization has also increased to fulfill humans’ living standards. Fungi are considered a source of essential constituents to produce the biocatalytic enzymes, including amylases, proteases, lipases, and cellulases that contain broad-spectrum industrial and emerging applications. The present review discussed the origin, nature, mechanism of action, emerging aspects of genetic engineering for designing novel proteases, genome editing of fungal strains through CRISPR technology, present challenges and future recommendations of fungal proteases. The emerging evidence revealed that fungal proteases show a protective role to many environmental exposures and discovered that an imbalance of protease inhibitors and proteases in the epithelial barriers leads to the protection of chronic eosinophilic airway inflammation. Moreover, mitoproteases recently were found to execute intense proteolytic processes that are crucial for mitochondrial integrity and homeostasis function, including mitochondrial biogenesis, protein synthesis, and apoptosis. The emerging evidence revealed that CRISPR/Cas9 technology had been successfully developed in various filamentous fungi and higher fungi for editing of specific genes. In addition to medical importance, fungal proteases are extensively used in different industries such as foods to prepare butter, fruits, juices, and cheese, and to increase their shelf life. It is concluded that hydrolysis of proteins in industries is one of the most significant applications of fungal enzymes that led to massive usage of proteomics.

Alexander Genser, Noel Hautle, Michail Makridis et al.

A reliable estimation of the traffic state in a network is essential, as it is the input of any traffic management strategy. The idea of using the same type of sensors along large networks is not feasible; as a result, data fusion from different sources for the same location should be performed. However, the problem of estimating the traffic state alongside combining input data from multiple sensors is complex for several reasons, such as variable specifications per sensor type, different noise levels, and heterogeneous data inputs. To assess sensor accuracy and propose a fusion methodology, we organized a video measurement campaign in an urban test area in Zurich, Switzerland. The work focuses on capturing traffic conditions regarding traffic flows and travel times. The video measurements are processed (a) manually for ground truth and (b) with an algorithm for license plate recognition. Additional processing of data from established thermal imaging cameras and the Google Distance Matrix allows for evaluating the various sensors’ accuracy and robustness. Finally, we propose an estimation baseline MLR (multiple linear regression) model (5% of ground truth) that is compared to a final MLR model that fuses the 5% sample with conventional loop detector and traffic signal data. The comparison results with the ground truth demonstrate the efficiency and robustness of the proposed assessment and estimation methodology.

J. Mihelcic, J. Crittenden, M. Small et al.