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Abstract In the next 25 years an unprecedented number of new marine artificial structures, over 75,000 offshore wind turbines alone, are planned to meet global net zero targets. Structures are required to last for multiple decades in the hostile marine environment; where the largest cost across their whole lifecycle is on operations and maintenance dependent on accessibility in calm seas. However, the role of climate change on accessibility, and thus operational cost, has not been resolved. Here we provide the first study of future accessibility; evaluated from global climate model driven wave modelling, using the high emission scenario (RCP8.5). We found that climate change drives significant regional variation in accessibility, with the northern hemisphere benefiting from a 6% increase in operating windows whilst accessibility in parts of the southern hemisphere is reduced by 6-9%. These findings will help offshore developers and stakeholders incorporate adaptions to climate change as part of strategic planning practices.

La production industrielle d'huile de palme génère simultanément une quantité substantielle de fibres de grappe de fruits vides (EFB) qui pourraient être utilisées comme matière première dans une bioraffinerie à base de lignocellulose. Les sous-produits de la lignine générés par ce processus peuvent offrir des possibilités d'isolation des produits à valeur ajoutée, tels que le p-hydroxybenzoate (pBz), pour aider à compenser les coûts d'exploitation. L'analyse de la lignine EFB par spectroscopie de résonance magnétique nucléaire (RMN) a clairement révélé la présence d'acétate lié et de pBz, la saponification révélant que 1,1 % en poids de l'EFB était du pBz ; avec une teneur en lignine de 22,7 %, 4,8 % de la lignine est du pBz qui peut être obtenu comme composant pur pour être utilisé comme charge chimique. L'analyse de la lignine EFB par RMN et dérivatisation suivie d'un clivage réducteur (DFRC) a montré que le pBz acylate sélectivement le groupe γ-hydroxyle des unités S. Cette sélectivité suggère que le pBz, de manière analogue à l'acétate dans le kénaf, le p-coumarate dans les graminées et le ferrate dans un peuplier transgénique augmenté d'une féruloyl-CoA monolignol transférase (FMT), est incorporé dans la chaîne de lignine en croissance via son conjugué monolignol γ-p-hydroxybenzoylé. L'implication de tels conjugués dans la lignification des palmiers est prouvée par l'observation de nouvelles unités couplées au β-β non résinol p-hydroxybenzoylé dans les lignines. Ensemble, les données impliquent l'existence de p-hydroxybenzoyl-CoA :monolignol transférases qui sont impliquées dans la lignification chez les différents saules (Salix spp.), peupliers et peupliers faux-trembles (Populus spp., famille des Salicacées) et palmiers (famille des Arecacées) qui ont des lignines p-hydroxybenzoylées. Même sans augmenter les niveaux par la sélection ou le génie génétique, les « déchets » actuels de l'EFB d'huile de palme devraient être en mesure de générer un flux important d'acide p-hydroxybenzoïque qui offre des opportunités pour le développement de produits à valeur ajoutée dérivés de l'industrie du palmier à huile. La producción industrial de aceite de palma genera simultáneamente una cantidad sustancial de fibras de racimo de frutas vacías (EFB) que podrían utilizarse como materia prima en una biorrefinería a base de lignocelulosa. Los subproductos de lignina generados por este proceso pueden ofrecer oportunidades para el aislamiento de productos de valor agregado, como el p-hidroxibenzoato (pBz), para ayudar a compensar los costos operativos. El análisis de la lignina EFB por espectroscopía de resonancia magnética nuclear (RMN) reveló claramente la presencia de acetato unido y pBz, y la saponificación reveló que el 1,1% en peso del EFB era pBz; con un contenido de lignina del 22,7 %, el 4,8 % de la lignina es pBz que se puede obtener como un componente puro para su uso como materia prima química. El análisis de la lignina EFB por RMN y la derivatización seguida de escisión reductora (DFRC) mostró que pBz acila selectivamente el grupo γ-hidroxilo de las unidades S. Esta selectividad sugiere que pBz, análogamente con acetato en kenaf, p-cumarato en gramíneas y ferular en un álamo transgénico aumentado con una feruloil-CoA monolignol transferasa (FMT), se incorpora a la cadena de lignina en crecimiento a través de su conjugado de monolignol γ-p-hidroxibenzoilado. La participación de dichos conjugados en la lignificación de la palma se demuestra al observar nuevas unidades no acopladas a β-β-resinol p-hidroxibenzoiladas en las ligninas. Juntos, los datos implican la existencia de p-hidroxibenzoil-CoA:monolignol transferasas que participan en la lignificación en los diversos sauces (Salix spp.), álamos y álamo temblón (Populus spp., familia Salicaceae) y palmeras (familia Arecaceae) que tienen ligninas p-hidroxibenzoiladas. Incluso sin mejorar los niveles mediante mejoramiento o ingeniería genética, los 'desechos' actuales de aceite de palma EFB deberían ser capaces de generar una corriente considerable de ácido p-hidroxibenzoico que ofrezca oportunidades para el desarrollo de productos de valor agregado derivados de la industria de la palma aceitera. The industrial production of palm oil concurrently generates a substantial amount of empty fruit bunch (EFB) fibers that could be used as a feedstock in a lignocellulose-based biorefinery. Lignin byproducts generated by this process may offer opportunities for the isolation of value-added products, such as p-hydroxybenzoate (pBz), to help offset operating costs. Analysis of the EFB lignin by nuclear magnetic resonance (NMR) spectroscopy clearly revealed the presence of bound acetate and pBz, with saponification revealing that 1.1 wt% of the EFB was pBz; with a lignin content of 22.7 %, 4.8 % of the lignin is pBz that can be obtained as a pure component for use as a chemical feedstock. Analysis of EFB lignin by NMR and derivatization followed by reductive cleavage (DFRC) showed that pBz selectively acylates the γ-hydroxyl group of S units. This selectivity suggests that pBz, analogously with acetate in kenaf, p-coumarate in grasses, and ferulate in a transgenic poplar augmented with a feruloyl-CoA monolignol transferase (FMT), is incorporated into the growing lignin chain via its γ-p-hydroxybenzoylated monolignol conjugate. Involvement of such conjugates in palm lignification is proven by the observation of novel p-hydroxybenzoylated non-resinol β–β-coupled units in the lignins. Together, the data implicate the existence of p-hydroxybenzoyl-CoA:monolignol transferases that are involved in lignification in the various willows (Salix spp.), poplars and aspen (Populus spp., family Salicaceae), and palms (family Arecaceae) that have p-hydroxybenzoylated lignins. Even without enhancing the levels by breeding or genetic engineering, current palm oil EFB 'wastes' should be able to generate a sizeable stream of p-hydroxybenzoic acid that offers opportunities for the development of value-added products derived from the oil palm industry. ينتج الإنتاج الصناعي لزيت النخيل في الوقت نفسه كمية كبيرة من ألياف مجموعة الفاكهة الفارغة (EFB) التي يمكن استخدامها كمادة وسيطة في مصفاة حيوية تعتمد على اللجينوسليلوز. قد توفر المنتجات الثانوية لليجنين الناتجة عن هذه العملية فرصًا لعزل المنتجات ذات القيمة المضافة، مثل p - hydroxybenzoate (pBz)، للمساعدة في تعويض تكاليف التشغيل. كشف تحليل اللجنين EFB بواسطة مطياف الرنين المغناطيسي النووي (NMR) بوضوح عن وجود أسيتات مرتبطة و pBz، مع كشف التصبن أن 1.1 ٪ بالوزن من EFB كان pBz ؛ مع محتوى اللجنين بنسبة 22.7 ٪، 4.8 ٪ من اللجنين عبارة عن pBz يمكن الحصول عليه كمكون نقي للاستخدام كمادة وسيطة كيميائية. أظهر تحليل اللجنين EFB بواسطة NMR والاشتقاق متبوعًا بالانقسام الاختزالي (DFRC) أن pBz يعمل بشكل انتقائي على أسيتيل مجموعة γ - hydroxyl من وحدات S. تشير هذه الانتقائية إلى أن pBz، بالتناظر مع الأسيتات في الكناف، و p - comarate في الأعشاب، و ferulate في حور معدّل وراثيًا معززًا بـ feruloyl - CoA monolignol transferase (FMT)، يتم دمجه في سلسلة اللجنين المتنامية عبر γ - p - hydroxybenzoylated monolignol conjugate. ثبت تورط مثل هذه المترافقات في ترصيع النخيل من خلال ملاحظة وحدات p - hydroxybenzoylated غير الراتينول β - β المقترنة في اللجنين. معا، تشير البيانات إلى وجود p - hydroxybenzoyl - CoA: monolignol transferases التي تشارك في تبييض في الصفصاف المختلفة (Salix spp.)، الحور والحور (Populus spp.، عائلة Salicaceae)، والنخيل (عائلة Arecaceae) التي تحتوي على p - hydroxybenzoylated lignins. حتى من دون تعزيز المستويات عن طريق التكاثر أو الهندسة الوراثية، يجب أن تكون "نفايات" زيت النخيل الحالية قادرة على توليد تيار كبير من حمض p - hydroxybenzoic الذي يوفر فرصًا لتطوير منتجات ذات قيمة مضافة مشتقة من صناعة نخيل الزيت.

Abstract Emissions and efficiency of a pellet boiler (40 kW) at nominal load were compared with emissions and efficiency at reduced load, while fired with six biomass pellets. The pellets include reed canary grass ( Phalaris arundinacea ), pectin waste from citrus shells ( Citrus reticulata ), sunflower husk ( Helianthus annuus ), peat, wheat straw ( Triticum aestivum ) and wood pellets. The measurements of emissions comprised of carbon monoxide (CO), nitrogen oxides (NO x ), sulphur oxides (SO x ) and flue dust mass concentrations (using DIN plus and isokinetic sampling techniques). Emissions varied as a function of operational loads, for each type of pellets. The CO emissions were insignificant with reed canary grass (RCG), citrus pectin waste (CPW) and straw pellets at nominal load, however, at reduced load same pellets emitted 1.9, 4.0 and 7.4 times higher CO than wood pellets, respectively. Peat pellets emitted maximum CO at nominal load (4221.1 mgNm −3 , 12.6 times higher than wood pellets) however; at reduced load CO emission was insignificant. The highest NO x emissions were reported with CPW, which were 3.4 and 4.6 times higher than wood pellets at nominal load and reduced load, respectively. Dust emissions were highest with sunflower husk and lowest with RCG pellets, at both operational modes. The best performance was reported with wood pellets, followed by RCG and pectin pellets, however, wood pellets combustion emitted 1.7 and 2.0 times higher dust DIN plus than RCG at nominal and reduced loads, respectively. Not only fuel specific combustion optimization but also operational load specific optimization is essential for efficient use of agro-pellets in this type of boilers.

In the current situation with the unprecedented deployment of clean technologies for electricity generation, it is natural to expect that storage will play an important role in electricity networks. This paper provides a qualitative methodology to select the appropriate technology or mix of technologies for different applications. The multiple comparisons according to different characteristics distinguish this paper from others about energy storage systems. Firstly, the different technologies available for energy storage, as discussed in the literature, are described and compared. The characteristics of the technologies are explained, including their current availability. In order to gain a better perspective, availability is cross-compared with maturity level. Moreover, information such as ratings, energy density, durability and costs is provided in table and graphic format for a straightforward comparison. Additionally, the different electric grid applications of energy storage technologies are described and categorised. For each of the categories, we describe the available technologies, both mature and potential. Finally, methods for connecting storage technologies are discussed.

Reconstruire les variations passées de notre climat permet de mieux appréhender le fonctionnement de notre système climatique.Les carottes de glace issues des calottes polaires et des glaciers montagneux de haute altitude sont de très bonnes archivesclimatiques. Les glaciers présents sur les sommets des Andes sud-américaines sont ainsi exploités depuis les années 80. Une dizainede carottages ont été réalisés depuis l’équateur jusqu’en Patagonie. Ils recouvrent des périodes très différentes allant du derniersiècle, jusqu’à la dernière transition glaciaire-interglaciaire qui débute il y a 21 000 ans. La datation de ces carottes combine unensemble de méthodes : comptage des cycles saisonniers des éléments chimiques et de la composition isotopique de la glace, analysede la concentration des éléments radioactifs issus des tests atmosphériques nucléaires au XXe siècle et modélisation de l’écoulementdu glacier pour la partie la plus profonde. Le présent article illustre deux résultats intéressants apportés par l’étude de la compositionisotopique de ces glaces. Le premier concerne la période du Petit Âge Glaciaire au XVIIe-XVIIIe siècle. L’analyse isotopique de la glacede deux carottes prélevées en Bolivie (Illimani) et au Pérou (Quelccaya), couplée à l’étude de l’extension des glaciers au mêmemoment, montre des conditions climatiques légèrement plus humides et plus froides de 1650 à 1780. Le second résultat est déduitde l’analyse isotopique d’une carotte prélevée en Patagonie du Nord (San Valentin) qui recouvre les 120 dernières années. L’enregistrementisotopique suggère que la température dans cette région a progressivement diminué au cours de cette période d’environ0,2 °C par décennie, venant prolonger une tendance mesurée par les stations météorologiques chiliennes depuis les années 70 malgréun contexte de réchauffement global. The reconstruction of past climate variability offers important information about our climate system. Ice cores extractedfrom polar ice sheets or from mountainous glaciers are among the most popular climate archives. Ice cores from Andean glaciersin South America have been studied since the 1980’s. Almost ten ice cores have been extracted from the equator to Patagonia. Theycover different time periods from the last century to the last glacial-interglacial termination that started 21,000 years ago. Those icecores are usually dated by using a combination of methods: annual layers counting in both isotopic and chemical ice composition,radionuclides concentration analysis to detect atmospheric nuclear tests during the 20th century and ice flow modeling for the deepestpart of those cores. This paper presents two interesting results arising from the isotopic composition of the ice. The first one dealswith the isotopic records of Bolivian (Illimani) and Peruvian (Quelccaya) ice cores in regards to the reconstruction of glacier extentduring the little ice age in the 17th-18th century. Both approaches suggest a slightly moister and cooler period from 1650 to 1780. Thesecond result arises from the 120-year long isotopic record of an ice core drilled in Patagonia (San Valentin). It suggests that at theregional scale, temperature has regularly decreased of about 0.2 °C per decade, extending the temperature decrease shown by Chileanmeteorological data since the 1970’s despite a global warming.

Little is known about the validity of repeated 24-h dietary recalls (24-HDR) as a measure of total energy intake (EI) in young children. This study aimed to evaluate the validity of proxy-reported EI by comparison with total energy expenditure (TEE) measured by the doubly labeled water (DLW) technique.The agreement between EI and TEE was investigated in 36 (47.2% boys) children aged 4-10 years from Belgium and Spain using subgroup analyses and Bland-Altman plots. Low-energy-reporters (LER), adequate-energy-reporters (AER) and high-energy-reporters (HER) were defined from the ratio of EI over TEE by application of age- and sex-specific cut-off values.There was good agreement between means of EI (1500 kcal/day) and TEE (1523 kcal/day) at group level though in single children, i.e. at the individual level, large differences were observed. Almost perfect agreement between EI and TEE was observed in thin/normal weight children (EI: 1511 kcal/day; TEE: 1513 kcal/day). Even in overweight/obese children the mean difference between EI and TEE was only -86 kcal/day. Among the participants, 28 (78%) were classified as AER, five (14%) as HER and three (8%) as LER.Two proxy-reported 24-HDRs were found to be a valid instrument to assess EI on group level but not on the individual level.

A reduced-order, “grey-box” model of an active distribution network, intended for dynamic simulations of the transmission system, is derived. The network hosts inverter-based generators as well as static and motor loads, whose dynamic parameters are affected by uncertainty. This issue is addressed using Monte-Carlo simulations. The parameters of the equivalent are adjusted to match as closely as possible the average of the randomized responses, while their dispersion is accounted for through the weights of the weighted least-square minimization. A procedure is used to remove from the identification the parameters with negligible impact. To avoid over-fitting, the equivalent is tuned for multiple large-disturbance simulations. A recursive procedure is used to select the smallest possible subset of disturbances involved in the least-square minimization. Simulation results with a 75-bus MV test-system are reported. They show that the equivalent is able to reproduce with good accuracy the discontinuous controls of inverter-based generators, such as reactive current injection and tripping.

In Belgium, and many other countries, rooftop solar panels are becoming a ubiquitous form of decentralised energy production. The increasing share of these distributed installations however imposes many challenges on the operators of the low-voltage distribution grid. They must keep the voltage levels and voltage balance on their grids in check and are often regulatory required to provide sufficient reception capacity for new power producing installations. By placing solar panels in different inclinations and azimuth angles, power production profiles can possibly be shifted to align more with residential power consumption profiles. In this article, it is investigated if the orientation of solar panels can have a mitigating impact on the integration problems on residential low voltage distribution grids. An improved simulation model of a solar panel installation is constructed, which is used to simulate the impact on a residential distribution grid. To stay as close to real-life conditions as possible, real irradiation data and a model of an existing grid are used. Both the developed model as the results on grid impact are evaluated.