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Identification of Quality Characteristics of Autochthonous Karasüt Apple during Cold Storage
No full textThe main objective of the research was to assess weight loss, respiration rate, firmness, soluble solids content (SSC), titratable acidity and vitamin C content of the autochthonous Karasüt apple throughout cold storage. The ‘Granny Smith’ cultivar was used as positive control. The fruit was kept at a temperature of 0.0±0.5°C and relative humidity of 90±5%. Quality losses were observed in the apples during cold storage. The weight loss of Karasüt apple (6.70%) was higher than that of Granny Smith (2.20%) at the end of cold storage. A lower respiration rate was measured in the Karasüt apple (1.23 nmol CO2 kg-1 s-1), compared to the positive control (1.53 nmol CO2 kg-1 s-1) at harvest. On the contrary, the respiration rate was higher on days 30 and 60. The fruit firmness of Granny Smith (27.14 N) was higher than that of Karasüt (22.47 N) at the end of cold storage. During the cold storage, a higher SSC was obtained from Karasüt apple compared to the positive control. However, titratable acidity was lower in Karasüt apple. In the first two measurements of cold storage, the vitamin C of Karasüt apple was higher than that of the positive control. As a result, it was revealed that Karasüt apple had faster quality losses during cold storage than Granny Smith apple cultivar
The effect of zinc, iron and manganese content on gamma shielding properties of magnesium-based alloys produced using the powder metallurgy
No full textThis study investigates the effects of Zinc (Zn), Manganese (Mn), and Iron (Fe) additions on the microstructure, corrosion behaviour, biocompatibility, mechanical, and gamma-ray shielding properties of Magnesium (Mg) alloys prepared in various compositions using powder metallurgy (PM). The microstructure and mechanical properties of these alloys were analyzed using electron microscopes (SEM and FE-SEM) and X-ray diffraction (XRD) methods. The results showed positive changes in the material's structure when the percentage of zinc added to pure magnesium increased. It was observed that the material became ductile, and the ductile fracture increased when the zinc ratio increased. The gamma-ray shielding properties of newly produced Mg-based alloys have also been discussed since they have a high potential for use in space technologies. Radiation shielding measurements have been performed using a 3′′ × 3″ NaI(Tl) scintillation detector NaI (Tl) gamma-ray spectrometer. The gamma-ray shielding parameters such as the linear attenuation coefficients (μl), mass attenuation coefficient (μm), effective atomic number (Zeff), half-value layer (HVL), and tenth-value layer (TVL) have been determined experimentally at photon energies of 0.511 MeV (emitted from a22Na radioactive point source) and 1.173 MeV and 1.332 MeV (emitting from a60Co radioactive point source). The obtained parameters have been compared to the theoretical results of the XCOM software, and a satisfactory agreement has been found. It can be said from the results that the Mg30Zn alloy has the best shielding properties among the produced materials
Crashbox desıgn ın vehıcles and analysıs wıth fınıte element method
No full textİÇİNDEKİLER TEŞEKKÜR ................................................................................................................ i İÇİNDEKİLER .......................................................................................................... ii KISALTMALAR ...................................................................................................... iv SİMGELER ................................................................................................................ v TABLOLAR LİSTESİ............................................................................................. vii ŞEKİLLER LİSTESİ..............................................................................................viii ÖZET......................................................................................................................... xii ABSTRACT.............................................................................................................xiii BÖLÜM 1. GİRİŞ .......................................................................................................................... 1 1.1. Literatür İncelemesi.......................................................................................... 1 1.2. Tezin Amacı ..................................................................................................... 6 BÖLÜM 2. TEORİLER VE METODLAR.................................................................................. 7 2.1. Çarpışma Dayanım Kriterleri ........................................................................... 7 2.2. Çöküş Modları.................................................................................................. 8 2.3. Çarpışma Dayanımı Göstergeleri ................................................................... 11 2.3.1. Emilen toplam enerji (ET)....................................................................... 11 2.3.2. Pik kuvveti (FP)....................................................................................... 12 2.3.3. Özgül enerji emilimi (SEA).................................................................... 12 2.3.4. Ana çarpışma kuvveti (FM)..................................................................... 12 2.3.5. Çarpışma kuvveti etkisi (CE) .................................................................. 13 2.4. Sonlu Eleman Modelelleme Yaklaşımı (FEM).............................................. 13 2.4.1. Impilicit dinamik analiz.......................................................................... 16 2.4.2. Expilicit dinamik analiz.......................................................................... 16 2.5. Dp Çeliklerin Genel Özellikleri ..................................................................... 17 2.5.1. Dp çeliklerin mekanik özellikleri ........................................................... 17 2.5.2. DP çeliklerin mikroyapısı....................................................................... 18 2.6. İnce Cidarlı Yapıların Çarpışma Dayanım Karakteristikleri.......................... 21 2.6.1. Boş tüplerin çarpışma dayanım davranışları........................................... 22 2.6.2. Tetikleyici mekanizmaya sahip çarpışma kutuları ................................. 27 2.6.3. Alüminyum köpük dolgulu tüplerin çarpışma dayanım davranışları ..... 32 2.6.4. Çok hücreli tüplerin çarpışma dayanım davranışları.............................. 39 iii 2.6.5. Kompozit tüplerin çarpışma dayanım davranışları................................. 43 BÖLÜM 3. TASARIM VE MODELLEME .............................................................................. 48 3.1. Çarpışma Kutularının Cad Modellemesi........................................................ 49 3.2. Sonlu Elemanlar Modelleme Yaklaşımı......................................................... 51 3.2.1. Başlangıç hızı ve sınır şartlarının belirlenmesi....................................... 52 3.2.3. Malzeme kartına özelliklerin girilmesi................................................... 55 3.2.4. Kabuğun kesit kalınlığının belirlenmesi................................................. 57 3.2.5. Parçaların özelliklerinin eşleştirilmesi.................................................... 58 3.2.6. Proje sonrası............................................................................................ 58 3.3. Çarpışma Kutularının Kodlanması ............................................................ 59 3.4. Numerik Simülasyon Sonuçlarının Elde Edilme Süreci ................................ 60 3.4.1. Modellerin kütlelerinin bulunması ......................................................... 60 3.4.2. Yer değiştirme-zaman grafiği................................................................. 61 3.4.3. Kuvvet-zaman grafiği ............................................................................. 62 3.4.4. Kuvvet-yer değiştirme grafiği................................................................. 63 3.4.5. Emilen toplam enerji grafiği................................................................... 65 BÖLÜM 4. NUMERİK SİMÜLASYONLAR ........................................................................... 67 4.1. Temsili Modellerin Simülasyon Sonuçları..................................................... 67 4.1.1. DP 600 malzeme özellikleri tanımlanmış tek parçadan oluşan modeller68 4.1.2. DP 600 malzeme özellikleri tanımlanmış sürtünme kuvvetiyle enerji emen modeller .................................................................................................. 73 4.1.3. DP 800 malzeme özellikleri tanımlanmış tek parçadan oluşan modeller78 4.1.4. DP 800 malzeme özellikleri tanımlanmış sürtünme kuvvetiyle enerji emen modeller .................................................................................................. 83 4.2. Enerji Grafiklerinin Yorumlanması................................................................ 87 4.3. Temsili Modellerin Pik Kuvvetlerinin Karşılaştırılması................................ 89 4.4. Normal ve Sürtünmeli Modellerin SEA Değerlerinin Karşılaştırılması ........ 90 4.5. Performans Verilerinin Optimizasyonu.......................................................... 91 4.6. Malzeme Özelliklerinin ve Sac Kalınlığının Çarpma Dayanımına Etkisi ..... 92 4.7. Çalışmanın Mevcut Literatürdeki Çalışmalarla Kıyaslanması....................... 95 BÖLÜM 5. SONUÇLAR ........................................................................................ 98 KAYNAKLAR ....................................................................................................... 100 EKLER……………………………………………………………………...….....107ARAÇLARDA ÇARPIŞMA KUTUSU (CRUSHBOX) TASARIMI VE SONLU ELEMANLAR YÖNTEMİ İLE ANALİZİ ÖZET Son yıllarda araçlarda kullanılan ince cidarlı yapıların enerji yutma yeteneklerinin arttırılmasına yönelik çalışmalarda önemli bir artış görülmektedir. Bu çalışmalar, çarpışma kutularının duvarlarına katlanmayı tetikleyen girinti ve çıkıntılar ekleyerek çarpışma sırasında ortaya çıkan şok dalgalarının olumsuz etkilerini azaltmayı ve böylece enerji emilimini artırmayı amaçlamaktadır. Çarpışma boncuğu adı verilen bu tetikleyiciler, çarpışma kutusunun plastik deformasyona uğramasını kolaylaştırarak, katlanma lobu oluşumlarıyla çarpışmadan kaynaklı darbe enerjisinin bir kısmını, kendi içinde hapsetmektedir. Bu özel çalışmada, katlanarak enerji emilimi sağlayan ince cidarlı yapılardan farklı olarak, sürtünme kuvveti ile enerji emilimi sağlayan ve üç bileşenden oluşan bir çarpışma kutusu geliştirilmiştir. Eksenel ezilme koşulları altında, katlanarak enerji emilimi sağlayan yapıların aksine, geliştirilen çarpışma kutusunu oluşturan bileşenler önce birbiri içine geçmekte, ardından katlanmaya başlamaktadır. Eksenel darbe yükü altında, çarpışma kutusunu oluşturan üç bileşen birbiri içine geçerken, sürtünme kuvveti üretmektedir. Parçalar tamamen birbiri içine geçtikten sonra, katlanma lobları oluşturarak enerji emilimine devam etmektedir. Bu çalışmada, yeni tasarlanan çarpışma kutusu tarafından üretilen sürtünme kuvvetinin, ince cidarlı yapıların enerji emilimine, çarpışma dayanımına ve ezilme davranışına etkisi araştırılmıştır. İnce cidarlı yapılarda sürtünme kuvvetinin darbe sönümlemesindeki etkisini belirlemek için iki farklı konfigürasyon modellenmiştir. Eksenel darbe yükünün uygulanmasıyla birinci konfigürasyon klasik katlanma davranışı sergilerken, diğer konfigürasyon iç içe geçtikten sonra katlanmaya başlamaktadır. İç içe geçen bileşenler, çarpışma kutusu yüzeyindeki girinti ve çıkıntılar aracılığıyla sürtünme kuvveti oluşturarak enerji emilimi sağlamaktadır. Simülasyonlar, doğrusal olmayan açık dinamik çarpışma senaryosunda sonlu elemanlar yöntemi (FEM) kullanılarak gerçekleştirilmiştir. Her iki konfigürasyon için çarpışma senaryoları, aynı koşullar altında, iki farklı malzeme (DP-600 ve DP-800) ve dört farklı kalınlık (1.0mm, 1,2 mm, 1,4 mm ve 1,5 mm) kullanılarak analiz edilmiştir. Çarpışma kutularının enerji soğurma yetenekleri ve ezilme davranışları üzerinde, sürtünme kuvvetinin etkilerini incelemek için, dinamik çarpışma simülasyonlarının sonuçları, Özgül Enerji Emilimi (SEA), Toplam Enerji (ET), Tepe Ezilme Kuvveti (PK), Ezilme Kuvveti Verimliliği (CE) ve Ortalama Ezme Kuvveti (FM) değerlerine göre karşılaştırılmıştır. Yapılan karşılaştırmalar sonucunda, pik kuvveti ve SEA değerlerine göre en verimli model belirlenmiştir. Malzeme özelliklerinin, sürtünme kuvvetiyle enerji emen sistemlerdeki çarpışma dayanımına etkisi araştırılmış, önceki çalışmalara göre avantajları ve dezavantajları tartışılmıştır. Analiz sonuçları, ince cidarlı yapıların çarpışmaya dayanıklılık özelliklerinde sürtünme kuvveti ile enerji emiliminin olumlu bir rol oynadığını göstermiştirCRASHBOX DESIGN IN VEHICLES AND ANALYSIS WITH FINITE ELEMENT METHOD ABSTRACT In recent years, there has been a significant increase in studies aimed at enhancing the energy absorption capabilities of thin-walled structures used in vehicles. These studies aim to mitigate the adverse effects of shock waves released during crashes by incorporating recess and protrusion that trigger folding on the walls of crash boxes, thereby increasing energy absorption. These triggers, called crush beads, facilitate the plastic deformation of the crushbox and absorb some of the impact energy resulting from the crush with folding lobe formations. In this particular study, a crushbox consisting of three components was developed that provides energy absorption with friction force, unlike thin-walled structures that provide energy absorption by folding. Under axial crushing conditions, unlike structures that absorb energy by folding, the components that make up the crushbox first interpenetrate of each other and then begin to fold. Under axial impact load, the three components forming the crushbox interact with each other and produce friction force. After the parts are completely interpenetrated, they continue to absorb energy by forming folding lobes. In this study, the effect of the friction force produced by the newly designed crushbox on the energy absorption, crashworthiness and crushing behavior of thin-walled structures was investigated. Two different configurations were modeled to determine the contribution of friction force in dampening impacts in thinwalled structures. With the application of axial impact load, the first configuration exhibited classical folding, while the other configuration began to fold after interpenetrating. Interpenetrating structures provide energy absorption by generating friction forces through recesses and protrusions on the surface of the crushbox. The simulations were conducted using the finite element method (FEM) in a non-linear explicit dynamic collision scenario. The crash scenarios for both configurations were analyzed under identical conditions using two different materials (DP-600 and DP800) and different thicknesses (1.0mm 1.2mm, 1.4mm, and 1.5mm). Results of the dynamic crash simulations were compared based on values of Specific Energy Absorption (SEA), Total Energy (ET), Peak Crush Force (PK), Crush Force Efficiency (CE), and Mean Crushing Force (FM) to investigate the effects of friction force on energy absorption capabilities and crushing behaviors of the crash boxes. As a result of the comparisons, the most efficient model was determined according to peak force and SEA values. The effects of material properties on crashworthiness in systems that absorb energy through friction force are investigated and their advantages and disadvantages compared to previous studies are discussed.The analysis results showed that energy absorption by friction force plays a positive role in the crashworthiness characteristics of thin-walled structure
Effect of longitudinal reinforcement ratio on residual flexural capacity of high-strength reinforced concrete beams exposed to impact loading
No full textIn this study, it was aimed to investigate the dynamic impact and post-impact performances of high-strength reinforced concrete (RC) beams, which have different ductility and load-bearing capacities. The dynamic behavior and impact damages of RC beams were compared after exposure to a constant magnitude of impact energy. The applied impact energy was obtained by dropping a mass of 360 kg from a certain height of 3 m. The cross-section dimensions and length of the specimens were selected to carry out the experiments in full-scale. The tested specimens were designed with five different longitudinal reinforcement ratios for demonstrating distinct structural behavior mechanisms that vary from pure flexure to pure shear, representing different ductilities, load-bearing capacities and potential failure characteristics. The post-impact behavior of the impacted RC beams was also assessed by performing quasi-static bending tests on the impact-damaged specimens and the obtained results were compared with the identical undamaged reference RC beams. The results demonstrated that the longitudinal reinforcement ratio (which was intentionally designed for different specimens to exhibit different structural responses from pure shear to pure flexural and different shear-flexure mechanisms) significantly influences the dynamic response and damage intensity of the beams, which, in turn, affect their post-impact static performance. Key structural characteristics, including residual displacement, ductility, energy dissipation, load-carrying capacity, and stiffness, were analyzed. It was found that the mechanical properties of the beams deteriorated markedly after impact exposure. A crucial finding of this research is the notable shift in failure modes from flexural to shear after impact, depending on the damage severity. In RC beams, shear damage remains insignificant under both impact loading and subsequent static loading when the ratio of shear strength to flexural strength (Vr/Mr) exceeds 1.5. Conversely, when this ratio is less than 1.5, the behavior transitions to being shear-critical or shear-dominant. This study presents, for the first time, comprehensive experimental results on the impact-induced damage progression, failure mechanisms, and residual behavior of high-strength RC beams. These insights are vital for understanding the performance of RC structures under impact loads and contribute significantly to the field of structural engineering, particularly in designing impact-resilient structures
The Analysis of Globalization, Hydroelectric Energy, Economic Growth, CO2 Emissions and Ecological Footprint Relationships for the USA: Fractional Fourier ADL Cointegration Method
No full textEnvironmental problems such as global climate change and global warming pose a great threat to future generations. The USA, which has a very high ecological footprint and carbon emissions, is at the forefront of the countries that pose this threat. In this direction, this study aims to investigate the effects of globalisation, economic growth and hydroelectric energy on carbon emission and ecological footprint in the USA with Fourier ADL cointegration and Fourier Toda-Yamamoto causality tests. According to the findings, there is a negative relationship between electricity generation from hydroelectric sources and CO2 emissions and a positive relationship between per capita GDP and ecological footprint. In addition, unidirectional causality from KOF to CO2, hydroelectric-powered electricity generation, and per capita GDP to ecological footprint are also determined
Effect of Adhesion and Corrosion Performance of Geomet Basecoat (321)- Topcoat (ML Black) Applications on Cataphoretic Coating
No full textThis study aimed to improve corrosion resistance and adhesion of metallic materials typically used in automotive application. A combination of cataphoretic and Geomet coatings has been used to improve corrosion resistance. Firstly, cataphoretic coating was applied and then the coating process was completed with Geomet 321 and ML Black respectively. The results of the corrosion tests were classified into different categories such as adhesion, water resistance, moisture resistance, salt resistance and cyclic tests. The corrosion properties of the two- and three-layer coatings were found to improve as a function of both the sandblast pre-treatment and the post-cataphoresis curing temperature. The findings show that the adhesion strength and corrosion properties of Geomet 321 increases with curing temperature and sandblasting. This study will be a contribution to the future of protective coatings in the automotive industry by describing the process steps necessary to achieve optimum results
Improving the tribological and corrosion behavior of Ni-B coating with low boron content from optimized lead-free bath on aluminum alloys
No full textThis study focuses on producing environmentally friendly, lead-free nickel-boron (Ni-B) coatings as an alternative to hard chromium coatings. Using the electroless method, the Ni-B coatings were fabricated from a leadfree bath, and the effects of varying B and Ni concentrations on the coatings' chemical composition, surface morphology, hardness, corrosion resistance, and wear performance were investigated. Scanning electron microscopy (SEM) and X-ray diffraction (XRD) were used to analyze surface morphology and phase composition. Corrosion performance was evaluated using potentiodynamic polarization (PP) and electrochemical impedance spectroscopy (EIS), while wear behavior was tested at sliding speeds of 20, 30, and 40 cm/s. The study highlights the critical role of sliding speed on wear mechanisms, friction coefficient, wear rate, and surface morphology. The analyses revealed that the optimal Ni-B coating, containing 34 g/L Ni and 3 g/L B, exhibited the highest hardness, the lowest corrosion rate, and the highest wear rate performance. The values obtained from these analyses were 891 HV for hardness, 8.87 x 10-6 mpy for corrosion rate, and 2.21 x 10-4 mm3/N & sdot;m for wear rate. The use of analysis of variance (ANOVA) identified key factors influencing these properties. The findings suggest that optimizing boron and nickel concentrations significantly enhances Ni-B coatings' corrosion resistance and wear performance, making them suitable for industrial applications
Investigation of conversion of waste heat into electric energy with thermoelectric generator system
No full textArtan nüfus ve enerji ihtiyacına karşılık azalan fosil yakıt rezervleri, yeni enerji üretim yöntemleri bulunması ve var olan enerji üretimlerinin verimlerinin arttırılması ihtiyacını doğurmuştur. Alternatif elektrik enerjisi üretim yöntemlerinin önümüzdeki yıllarda önemini daha da fazla arttırması beklenmektedir. Bu çalışma, bir tekstil fabrikasında Jarse Bronzing prosesi sonrası kullanılan sıcak odadaki atık ısıdan elektrik üretimi amaçlı gerçekleştirilmiştir. Çalışma, Ansys analizi ve deneysel ölçüm olarak yapılmıştır. İlk adımda termoelement tasarımı yapılarak, sonlu elemanlar yöntemiyle analizi için Ansys ortamına aktarılmıştır. Ansys kullanılarak, Thermal-Electric analizleri için çeşitli mesh eleman sayılarında çalışmalar yapılmıştır. Mesh kalite değerlerinin de incelenerek (aspect ratio, skewness ve orthogonal quality) göz önünde bulundurulmasıyla optimum mesh elemanı seçilerek farklı sınır şartları ile iligili 46 analiz yapılmıştır. Analizler sonrasında deneysel çalışmalarla, ilgili ölçümler yapılmıştır. Analizler ve deneysel çalışmalarda 2 farklı tipte peltier kullanılmıştır. Ölçümler bir tekstil fabrikasının boyahanesine gelen sıcak buhar hattı üzerinde yapılmıştır. Sonuçlar, Ansys'de Thermal-Electric analiz sonuçları ile karşılaştırılmıştır. TEC1-12710 tip TEG kullanılarak; 50,3°C sıcaklık farkında (TEG sıcak ve soğuk yüzey sıcaklık farkıdır), ortam sıcaklığı 41,6°C deneysel çalışmada gerilim değeri 0,268V iken, analiz sonucunda 0,26V gerilim değeri bulunmuştur. Deneysel çalışma ve analiz çalışması sonuçları arasında %2,85 fark vardır. Deneysel çalışma sonuçlarıyla korelasyon katsayısı hesaplanarak eğri uydurulmuş ve hata payı %6,88 olarak bulunmuştur. SP1848-27145 tip TEG kullanılarak; 57,3°C sıcaklık farkında (TEG sıcak ve soğuk yüzey sıcaklık farkıdır), ortam sıcaklığı 37,1°C deneysel çalışmada gerilim değeri 0,241V iken, analiz sonucunda 0,238V gerilim değeri bulunmuştur. Deneysel çalışma ve analiz çalışması sonuçları arasında %1,25 fark vardır. Deneysel çalışma sonuçlarıyla korelasyon katsayısı hesaplanarak eğri uydurulmuş ve hata payı %36,31 olarak bulunmuştur. Sistem 100 TEG ile kurulduğunda, TEC1-12710 tip TEG'in basit geri ödeme süresi 11,5 yıl, SP1848-27145 tip TEG'in basit geri ödeme süresi ise 5,4 yıl olarak bulunmuştur. TEC1-12710 tip TEG kullanılırsa yıllık karbon emisyon kazancı 0,11 〖tCO〗_2, SP1848-27145 tip TEG kullanılırsa yıllık karbon emisyon kazancı ise 0,39 〖tCO〗_2 olarak hesaplanmıştır
On the 3D wave propagation response of sandwich nanoplates with symmetric FGM face layers and GPRL-reinforced foam core layer
No full textThis study investigates 3D wave propagation in a sandwich nanosensor plate, emphasizing thermo-mechanical characteristics. The research employs sinusoidal higher-order shear deformation and nonlocal strain gradient elasticity theories on sandwich construction, including functionally graded ceramic (Si3N4) and metal (Ti6Al4V) face layers and a graphene-reinforced metal foam core. The governing equations are formulated using Hamilton's principle and resolved by the Navier method, integrating temperature, Lorentz, and viscoelastic effects. The primary characteristics examined encompass graphene volume fraction, temperature fluctuations, nonlocal effects, foam porosity, and magnetic potential. The results demonstrate a phase velocity of almost 4.2 km/s at wave numbers above 100 1/nm at ΔT = 0, diminishing to approximately 3.0 km/s as ΔT approaches 1200. The findings enhance the optimization of nanosensor design for dependability under elevated temperature conditions. © The Author(s), under exclusive licence to Società Italiana di Fisica and Springer-Verlag GmbH Germany, part of Springer Nature 2024
Bibliometric analysis on hydrogen and ammonia: a comparative evaluation for achieving IMO’s decarbonization targets
No full textIn the last decade, shipping emissions have emerged as a prominent contributor to climate change. In 2018, the IMO introduced a strategy encompassing short-, mid-, and long-term actions to address this issue. Future studies should prioritize clean alternative fuels to ensure adequate implementation supports the strategy's long-term objectives, effectively reducing shipping emissions. This study aimed to present a comprehensive evaluation of the carbon–neutral alternative fuels hydrogen and ammonia for reducing CO2 emissions from ships. Moreover, a bibliometric analysis was conducted using data obtained from the SCOPUS database to comprehend relevant topics, enhance collaboration networks, and determine research focal points. A total of 920 journal articles published from 2000 to December 2022 were retrieved and evaluated. The findings revealed that after the 2015 Paris Agreement and the IMO vision of 2018, the number of publications increased exponentially, leading to a continuous increase in the total number of publications to date. The searches conducted in the Scopus database using the keywords “alternative fuels”, “hydrogen” and “ammonia” in relation to maritime transportation indicate that researchers from the United States, China, and the United Kingdom collectively contributed to approximately 50% of the total scientific publications. The findings of this study shed light on the current state of research on hydrogen and ammonia as alternative fuels in the context of maritime transportation, providing invaluable references and insights to guide future studies, with the IMO’s net-zero carbon emission targets serving as a critical cornerstone for identifying key research directions. © The Author(s) under exclusive licence to Iranian Society of Environmentalists (IRSEN) and Science and Research Branch, Islamic Azad University 2024