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Construction of Environment-Friendly PVA/Chitin Composite Foams via Supercritical Carbon Dioxide Foaming for Wastewater Treatment
No full textWater pollution, particularly from heavy metal ions, remains a major environmental challenge, necessitating the development of cost-effective and sustainable adsorbents. This study presents a novel polyvinyl alcohol (PVA)/chitin composite foam synthesized via solid-state shearing milling (S3M) and supercritical carbon dioxide (scCO2) foaming technologies. The composite foams with high cell density exhibited improved structural integrity, mechanical strength, and adsorption capacity. The composite foam with 10% chitin loading demonstrated a 193% increase in copper ion adsorption and a 56% improvement for lead ions compared to pure PVA foam. The results indicate that the synergistic effect of PVA and chitin enhances the comprehensive performance of the foams parts
Electric Vehicle Electromagnetic Compatibility Testing and Electromagnetic Emission Mitigations
No full textAmidst the rapidly evolving landscape of road transportation, the imperative for sustainable and eco-friendly solutions is underscored by global regulations aimed at reducing CO2 emissions from vehicles. This heightened global awareness thrusts electric vehicles (EVs) into the forefront. While transitioning to EVs promises a reduction in CO2 emissions compared to conventional vehicles, it also raises concerns regarding electromagnetic compatibility (EMC) assurance. This study initiates by examining electromagnetic compatibility standards and testing requirements for electric vehicles. Then, technical approaches and critical factors such as grounding strategy, cable routing considerations and electromagnetic shielding to mitigate electromagnetic emissions are investigated. After that, vehicle-level EMC testing and assessment of electromagnetic emissions from an electric vehicle is conducted, in compliance with UNECE regulation no. 10. Radiated and conducted emissions are measured during EV charging by following CISPR 12 standard. It is obtained that the measurements of emission testing conform to the specified limits delineated in CISPR 12. Consequently, the electric vehicle under examination successfully meets both radiated and conducted emissions requirements
Solar Cell Anomaly Detection by ResNet Work with SE Attention Module
No full textAiming at the limitations of low detection accuracy and low detection efficiency of current anomaly detection methods for solar cells, especially the insufficient detection of subtle defects such as cracks and finger failures, an anomaly detection model SE-PatchCore is proposed for anomaly detection of solar cells in electroluminescence (EL) images by adding attention module in ResNet. Firstly, the SE (Squeeze and Excitation) attention mechanism is introduced into ResNet, and the network is applied to the advanced local anomaly detection model PatchCore. Finally, the Fair k-Centers method is used for coreset subsampling. Through testing on ELPV dataset, the score of SE-PatchCore in image-level AUROC is up to 98.7%, and the score of pixel-level AUROC is up to 98.5%, which has an improvement of 0.2% and 0.6% compared with PatchCore. And it has higher improvement over other methods such as SPADE and PaDiM. A higher AUROC score means the model can more accurately distinguish defective solar cells from normal ones and reduce false positives and false negatives. This helps to cut down on unnecessary rework, lower production costs, and ensure that more high-quality solar cells reach the market, meeting the increasing demand for reliable renewable energy products. The above results show that the introduction of SE attention module and the Fair k-Centers method can effectively improve the accuracy of anomaly detection of solar cells in EL images, which provides strong technical support for solving problems in this field
Maximizing Photovoltaic Power Output in Partial Shading Conditions for Electric Vehicle Applications: A Comparative Study of Intelligent Control Strategies
No full textThe increasing demand for sustainable transportation has positioned Electric Vehicles (EVs) as a key application area for photovoltaic (PV) systems. This study aims to enhance PV performance under Partial Shading Conditions (PSCs) by employing advanced Maximum Power Point Tracking (MPPT) algorithms. A comprehensive simulation model featuring a boost converter and battery integration is developed to evaluate and compare three MPPT techniques: the conventional Perturb and Observe (P&O) method, Grey Wolf Optimization (GWO), and Fuzzy Logic Control. Unlike previous studies, this work conducts a structured and comparative performance analysis across four distinct and progressively complex shading scenarios. Performance metrics include average power output, convergence time, and steady-state oscillations. Simulation results under shading patterns SP1 to SP4 indicate that the Fuzzy Logic approach achieves superior performance, with mean power outputs of 997.094 W (SP1) and 410.081 W (SP4), outperforming GWO by 1.7% and 0.7%, respectively. These findings offer quantitative evidence for the effectiveness of intelligent MPPT methods in enabling robust and efficient PV integration for EV applications
Determination of the Composition of Fatty Acids and Colored Components in Olive Oil
No full textCilj rada bio je ispitati kvalitetu četiriju uzoraka ekstra djevičanskih maslinovih ulja dobivenih od različitih sorti maslina uzgojenih na različitim lokalitetima, ali pod sličnim klimatskim uvjetima uzgoja, proizvedenim postupkom hladnog prešanja na hidrauličnim pužnim presama. U ispitivanim uzorcima određen je sastav masnih kiselina, sadržaj vode, netopljivih nečistoća i bojenih komponenti kao i ukupan sadržaj fenola, klorofila i karotenoida. Tri uzorka maslinovih ulja bila su iz Bosne i Hercegovine, dok je četvrti uzorak porijeklom iz Republike Slovenije. Od nezasićenih masnih kiselina iz reda mononezasićenih (MUFA), kod svih uzoraka je najzastupljenija oleinska kiselina i to od 68,50 do 70,16%. Na osnovi sadržaja pojedinačnih masnih kiselina izračunati su i nutritivni indeksi kod ispitivanih uzoraka maslinovih ulja. Vrijednost aterogenog indeksa (AI) u svim ispitivanim uzorcima bila je 0,14 do 0,19, dok se vrijednost trombogenog indeksa (TI) kretala u rasponu od 0,39 do 0,46. Hipokolesterolski/hiperkolesterolski indeks (HH) kod svih ispitivanih uzoraka maslinovih ulja kretao se od 5,82 do 7,81. Vrijednosti kiselina iz skupine ω-6 kretale su se od 0,43 do 0,74% i dominantnije su u odnosu na skupinu ω-3 (0,21–0,53%). Sadržaj vlage kod svih uzoraka manji je od 0,4%, dok je sadržaj netopljivih nečistoća veći od maksimalno dopuštenih vrijednosti (0,05%). Sadržaj karotenoida kretao se od 7,32 do 13,37mgkg−1, klorofila od 9,07 do 12,47mgkg−1, a ukupnih fenola od 195,86 do 328,45mgkg−1GAE. Rezultati pokazuju da svi uzorci maslinova ulja odgovaraju zahtjevima Pravilnika. Kemijske analize nisu pokazale statistički značajne razlike u kvaliteti ulja.The aim of this study was to examine the quality of four samples of extra virgin olive oil obtained from different olive varieties grown in different locations but under similar climatic conditions, produced by cold pressing with hydraulic screw presses. The composition of fatty acids, water content, insoluble impurities, and coloured components, as well as the total content of phenols, chlorophyll, and carotenoids, were determined in the tested samples. Three olive oil samples originated from Bosnia and Herzegovina, while the fourth sample originated from the Republic of Slovenia. Among the unsaturated fatty acids from the order of monounsaturated (MUFA), oleic acid was the most abundant in all samples, ranging from 68.50 to 70.16%. Based on the content of individual fatty acids, nutritional indices were also calculated for the tested olive oil samples. The atherogenic index (AI) value in all tested samples ranged from 0.14 to 0.19, while the thrombogenic index (TI) value ranged from 0.39 to 0.46. The hypocholesterol/hypercholesterol index (HH) in all tested olive oil samples ranged from 5.82 to 7.81. The values of acids from the ω-6 group ranged from 0.43 to 0.74% and were more dominant than the ω-3 group (0.21–0.53%). The moisture content in all samples was less than 0.4%, while the content of insoluble impurities was higher than the maximum allowed values (0.05%). The content of carotenoids ranged from 7.32 to 13.37mgkg−1, chlorophyll from 9.07 to 12.47mgkg−1, and total phenols from 195.86 to 328.45mgkg−1GAE. The results show that all the olive oil samples met the requirements of the relevant regulations. Chemical analysis did not reveal statistically significant differences in oil quality
Jahn-Teller Effect in Copper(II) Coordination Compounds withHalideIons
No full textIstražena je strukturna deformacija bakrovih(II) oktaedarskih koordinacijskih spojeva tipa CuX4A2 (X=F, Cl, Br; A = definiran kao bilo koji nemetal) uslijed Jahn-Tellerova efekta. U fokusu analize su deformacije prisutne u kutovima veza, duljinama veza te razlikama između duljina veza, s posebnom usporedbom cis- i trans-izomera. Na temelju parametara odstupanja oktaedarske strukture od idealne geometrije predložen je način klasifikacije za procjenu razine strukturne deformacije oktaedra. Rezultati ukazuju na prisutnost manjih ili vrlo malih deformacija ponajprije u strukturama koje pretežno sadrže monomerne kompleksne vrste te ne sadrže didentatne ligande, dok strukture s većim ili vrlo velikim deformacijama uglavnom sadrže didentatne ligande ili se sastoje od dimernih, trimernih ili polimernih kompleksnih vrsta. Jahn-Tellerov efekt manifestira se uglavnom kroz deformacije duljina veza između bakrova(II) iona i halogenidnih iona u odnosu na veze s heteroatomom. Analiza skupa od 123 koordinacijska spoja pokazala je učestalost trans-izomernih naspram cis-izomernih struktura, što je korelirano s većim oktaedarskim deformacijama, odnosno ukazuje na povezanost cis- i trans-izomerije i stupnja geometrijske deformacije oktaedarske strukture.This study investigates the structural deformation of copper(II) octahedral coordination compounds caused by the Jahn-Teller effect. The analysis focuses on distortions in bond angles, bond lengths, and differences in bond lengths, with a specific comparison between cis and trans isomers. A classification system is proposed for assessing the level of octahedral distortion based on deviations from an ideal octahedron. The findings indicate that structures with weak or very weak distortions are primarily monomeric units lacking bidentate ligands, while those with strong or very strong distortions often contain bidentate ligands or consist of monomeric, dimeric, or trimeric units. The Jahn-Teller effect was found to manifest predominantly through bond distance deformations between copper and halide ions, as compared to heteroatom bonds. Additionally, elongated octahedral geometries were more prevalent than compressed ones. Of the 123 analysed structures, trans isomerism occurred more frequently, as opposed to cis isomerism. The occurrence of trans isomers increased with stronger octahedral distortions, highlighting a relationship between isomerism and the degree of geometric deformation
Učinak vinase, otpada iz tvornice šećera, na proizvodnju biometana u industrijskim i mezofilnim uvjetima
No full textIn this study, the potential for biomethane production from vinasse, a waste by-product of sugar factories, was evaluated in a biogas unit under mesophilic conditions. The organic raw materials used in the biomethane potential (BMP) experiment were mixed with fermenter liquid (inoculum) at defined rates after laboratory determination of dry matter (%) and volatile solids (%). The facility was then simulated in a gas mesophilic environment for 30days to monitor the gas output.
Industrial challenges associated with the use of vinasse as a sugar factory waste in biomethane production, and the impurity values such as possible contamination during the supply of vinasse, can be evaluated as limiting factors. The biogas produced in the reactor contained CH4, CO2 and H2S gases. The ratio of inoculum to solid content in the organic matter was used to calculate the biomethane yield by means of the BMP device of the organic additives used in the study. When the biogas production from sugar factory waste was examined under one-year storage conditions, it was observed that optimisation of the stored waste would enable production under industrial conditions. According to the findings of this study, vinasse was used to produce biomethane, demonstrating its potential for industrial-scale waste management aligned with circular economy principles.U ovom radu ispitan je potencijal proizvodnje biometana iz vinase, otpadnog nusproizvoda tvornica šećera, u bioplinskoj jedinici koja radi u mezofilnim uvjetima. U pokusu određivanja potencijala biometana (BMP) vinasa je, nakon analize udjela suhe tvari i hlapljivih krutih tvari, miješana s fermentacijskom tekućinom (inokulumom) u unaprijed definiranim omjerima. Proces je proveden tijekom 30 dana u mezofilnim uvjetima da bi se kontinuirano pratio nastanak bioplina.
Kao mogući ograničavajući čimbenici identificirani su industrijski izazovi primjene vinase u proizvodnji biometana, uključujući i rizik od onečišćenja tijekom prikupljanja i opskrbe vinase. Bioplin proizveden u reaktoru sadržavao je CH4, CO2 i H2S, a iskorištenje biometana određeno je na temelju omjera inokuluma i udjela krute tvari u dodanom organskom materijalu upotrebom BMP uređaja.
Analiza proizvodnje bioplina iz otpada tvornice šećera pod uvjetima jednogodišnjeg skladištenja pokazala je da bi optimizacija načina skladištenja i rukovanja otpadom mogla omogućiti učinkovitu primjenu procesa na industrijskoj razini. Dobiveni rezultati potvrđuju da se vinasa može uspješno valorizirati za proizvodnju biometana te ima važan potencijal u sklopu održivog gospodarenja otpadom i kružnog gospodarstva
Productivity and Efficiency of Extracting Small-Sized Eucalyptus Logs by Farm Tractors with Backhoe Grapples in Thailand Short-Rotation Forestry
Get PDFIdentifying effective methods for harvesting wood in short-rotation planted forests has recently become challenging, especially when trying to balance differing perspectives on the issue. In addition, practice in such forests may be highly variable from one place to another, and models are required to better understand the effectiveness of planted forest management and to make better decisions. A simulation experiment was setup in this study to understand how the productive performance of farm tractors, which is a common technical option in Thailand, is affected when extracting small-sized eucalyptus payloads sourced by very short cycles. Two tractors (hereafter T1 and T2) of different class size and fitted with backhoe grapples were selected and monitored via GNSS. Operational events were extracted from GNSS data, and were characterized by their speed, while payload size was estimated based on manual measurement done in the field. Then, simulations were carried out to see how moving speed and payload size may affect the productive performance as a function of extraction distance. Significant differences (α=0.05) in speed and payload size led to substantial variations in performance as the extraction distance increased. For instance, the number of daily work cycles were similar for both machines in a distance range of up to 100 m; daily production (m3), productivity (m3/h), and efficiency (h/m3), on the other hand, have shown important differences, with the higher size class T1 being more performant. Payload size and moving speed had a strong effect on efficiency, tripling the unit time for T2 at a distance of 1000 m. These findings have important consequences, at least for the local practice in South East Asia. Since these machines are frequently used interchangeably, the average extraction distance should be limited to 50 m, a scenario in which the differences in performance are the lowest. T1 maintains higher daily production and a greater number of work cycles at longer distances, highlighting the importance of choosing the appropriate tractor size for varying extraction distances in short-rotation eucalyptus forestry. Furthermore, the extraction distance should also be planned based on the performance of upstream and downstream processes, since the local practice makes use of motor-manual tree felling and cross-cutting, manual delimbing and bunching, and medium capacity trucks
INTERPRETACIJA TALOŽNIH SUSTAVA I IZVORIŠTA MATERIJALA DONJOMIOCENSKIH NASLAGA U BAZENU CUU LONGA, VIJETNAM, NA TEMELJU U-PB GEOKRONOLOGIJE DETRITIČNIH ZRNA CIRKONA
No full textThe oil and gas industry faces increasing challenges in replenishing reserves. Enhancing exploration efficiency requires the integration of diverse datasets to build robust geological models. This study investigates the provenance and depositional systems of Lower Miocene sandstone reservoirs in the Cuu Long Basin (CLB), offshore Vietnam. We integrate 3D seismic, wireline log, conventional core, and detrital zircon U-Pb geochronological data to build a comprehensive source-to-sink model. Our findings reveal that the clastic components of the Lower Miocene sandstones (formations BI.1 and BI.2) predominantly originate from Cretaceous (ca. 105–108 Ma) magmatic rocks of the adjacent Dalat Zone on the Vietnamese mainland, with minor contributions from recycled older crustal sources. Seismic and well data show deposition occurred in environments ranging from alluvial-fluvial plains to more marine-influenced deltaic and coastal plain settings. This work provides new, high-resolution constraints on the provenance, depositional systems, and tectonic controls that influenced reservoir development in the Early Miocene CLB, offering crucial insight for future hydrocarbon exploration in the region.Naftna i plinska industrija suočava se sa sve većim izazovima u obnavljanju rezervi ležišta. Povećanje učinkovitosti istraživanja zahtijeva integraciju različitih skupova podataka kako bi se izgradili pouzdani geološki modeli. Ova studija istražuje podrijetlo i sustave taloženja ležišta donjomiocenskih pješčenjaka u bazenu Cuu Longa (CLB) na obali Vijetnama. U okviru rada integrirani su 3D seizmički, karotažni te konvencionalni podatci iz jezgara uz analize detritičnih zrna cirkona U-Pb metodom za utvrđivanje starosti. Provedena analiza načinjena je u svrhu izrade modela transporta od izvora do taložnoga prostora. Rezultati su pokazali da klastične komponente donjomiocenskih pješčenjaka (formacije BI.1 i BI.2) pretežno potječu iz magmatskih stijena kredne starosti (otprilike 105 do 108 milijuna godina) koje se nalaze u susjednoj Dalat Zoni na vijetnamskome kopnu, uz manji broj starijih, višestruko resedimentiranih zrna. Seizmički i bušotinski podatci pokazuju da se taloženje događalo u raznim okolišima, od aluvijalno-fluvijalnih ravnica do deltskih i obalnih ravnica koje su bile pod većim utjecajem mora. Ovaj rad pruža nove, vrlo precizne informacije o podrijetlu, taložnim sustavima i tektonskim značajkama koje su utjecale na razvoj ležišta u donjomiocenskim naslagama CLB-a, nudeći ključne uvide za buduća istraživanja ugljikovodika u regiji