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排序方式: 共有683条查询结果,搜索用时 15 毫秒
671.
Sergio Jurado Beatriz Domínguez-Prez Ona Illa Jan Balzarini Flix Busqu Ramon Alibs 《International journal of molecular sciences》2022,23(17)
The enantioselective preparation of the two isomers of 4-hydroxy-2-cyclohexanone derivatives 1a,b was achieved, starting from a common cyclohexenone, through asymmetric transfer hydrogenation (ATH) reactions using bifunctional ruthenium catalysts. From these versatile intermediates, a stereoselective route to a cytosine analogue built on a bicyclo [4.1.0]heptane scaffold is described. Nucleoside kinase activity assays with this cyclopropyl-fused cyclohexane nucleoside, together with other related nucleosides (2a–e), were performed, showing that thymine- and guanine- containing compounds have affinity for herpes simplex virus Type 1 (HSV-1) thymidine kinase (TK) but not for human cytosolic TK-1, thus pointing to their selectivity for herpetic TKs but not cellular TKs. 相似文献
672.
Sara Castro-Barquero Rosa Casas Eric B. Rimm Anna Tresserra-Rimbau Dora Romaguera J. Alfredo Martínez Jordi Salas-Salvadó Miguel A. Martínez-González Josep Vidal Miguel Ruiz-Canela Jadwiga Konieczna Emilio Sacanella Jesús Francisco García-Gavilán Montse Fitó Ana García-Arellano Ramon Estruch 《Molecular nutrition & food research》2023,67(4):2200264
673.
674.
The present work takes advantage of green electrospinning to create novel composite multifunctional nanofibers (NFs) bearing inorganic nanoparticles (NPs), more specifically quantum dots (QDs), cerium oxide nanoparticles (CeO2 NPs) and iron oxide nanoparticles (Fe3O4 NPs). This is achieved by first encapsulating the desired inorganic NPs into polymer particles by the use of miniemulsion polymerization, and second, spinning the hybrid polymer particles using polyvinyl alcohol (PVA) as template polymer. It is proved that using green electrospinning, it is not only possible to ensure an excellent distribution and encapsulation of the inorganic NPs along the NFs, but also allows to control and change the concentration, size, and type of the inorganic NPs without altering the NFs size, a fact that is not possible by conventional solution electrospinning. As proof of concept, NFs with up to three different types of inorganic NPs have been created in a single electrospinning step, but this technology allows to incorporate as much inorganic NPs as desired without altering the NFs morphology and ensuring a good distribution and encapsulation of the NPs. This paper demonstrates that green electrospinning is a powerful and attractive technology to create multifunctional NFs that are promising materials for sensing and biomedical applications. 相似文献
675.
Multiscale modeling in food engineering 总被引:1,自引:0,他引:1
Quang T. Ho Jan Carmeliet Ashim K. Datta Thijs Defraeye Mulugeta A. Delele Els Herremans Linus Opara Herman Ramon Engelbert Tijskens Ruud van der Sman Paul Van Liedekerke Pieter Verboven Bart M. Nicolaï 《Journal of food engineering》2013
Since many years food engineers have attempted to describe physical phenomena such as heat and mass transfer that occur in food during unit operations by means of mathematical models. Foods are hierarchically structured and have features that extend from the molecular scale to the food plant scale. In order to reduce computational complexity, food features at the fine scale are usually not modeled explicitly but incorporated through averaging procedures into models that operate at the coarse scale. As a consequence, detailed insight into the processes at the microscale is lost, and the coarse scale model parameters are apparent rather than physical parameters. As it is impractical to measure these parameters for the large number of foods that exist, the use of advanced mathematical models in the food industry is still limited. A new modeling paradigm – multiscale modeling – has appeared that may alleviate these problems. Multiscale models are essentially a hierarchy of sub-models which describe the material behavior at different spatial scales in such a way that the sub-models are interconnected. In this article we will introduce the underlying physical and computational concepts. We will give an overview of applications of multiscale modeling in food engineering, and discuss future prospects. 相似文献
676.
Alex Zea Guillem Valero Andrea‐NekaneR. Alba Albert Moyano Ramon Rios 《Advanced Synthesis \u0026amp; Catalysis》2010,352(7):1102-1106
For the first time, the addition of anthrones to maleimides catalyzed by bifunctional thiourea catalysts is reported. The thiourea moiety is able to activate the maleimide and the tertiary amine deprotonates the anthrone, furnishing the final Diels–Alder or Michael adducts in excellent yields and enantioselectivities. 相似文献
677.
Rosa Arredondo Zhongshun Yuan Dennise Sosa Anthony Johnson Ramon Filipe Beims Hongwei Li Qiang Wei Chunbao Charles Xu 《加拿大化工杂志》2023,101(4):1762-1771
Superabsorbent polymers (SAPs) have attracted tremendous attention recently, with researchers noting that their high water absorbability is valuable for various applications, especially in agricultural contexts. Two types of materials can be used to produce SAPs: Fossil-based (which are harmful to the environment) and bio-based (which are significantly more environmentally friendly, given their biodegradability and minimal toxic side effects). Although bio-based SAPs are preferable for environmental reasons, their synthesis tends to be time consuming and labour intensive, while their absorption capacity (AC) can be far below expectations. To address these problems, a novel, eco-friendly, cellulose-based superabsorbent polymer (Cellulo-SAP) was developed in this study through facile preparation via free radical synthesis using modified cellulose. Then, the absorbency, thermal/pH stability, reusability, and biodegradability of Cellulo-SAP were evaluated. This new polymer demonstrated reusability as a water reservoir, in addition to high thermal and pH stability. More importantly, Cellulo-SAP achieved an AC of 475 g/g and exhibited superior biodegradability compared to a commercial, fossil-based SAP. Accordingly, these results prove that Cellulo-SAP can be used in agriculture as an effective alternative to fossil-based SAPs. 相似文献
678.
Iñaki Emaldi Edurne Erkizia Jose Ramon Leiza Jorge S. Dolado 《Journal of the American Ceramic Society》2023,106(4):2567-2579
Polycarboxylic ethers or polycarboxylate (PCEs) are one of the most employed superplasticizers in construction. However, the understanding of their microstructure–property relationship is still incomplete. Recently, a theoretical model was proposed that relates the microstructure–conformation of the PCE to its effect on the adsorption onto cement particles and cement hydration time. In this work, the effects of a wide range of PCEs with different side chain lengths (P = 5, Group 1; P = 20, Group 2; and P = 45 and 113, Group 3) having flexible backbone worm conformation except one which has stretch backbone worm conformation (P = 113) were experimentally investigated for their effect on adsorption and cement hydration. It is found that PCEs from Group 1 show electrostatic repulsion as dispersing mechanism, unlike PCEs from Groups 2 and 3. Furthermore, the prediction of the theoretical model is also assessed for all the studied PCEs. Only Group 1 PCEs (shortest side chains) showed deviation from the theoretical predictions, and it was attributed to their different behaviors from the standard PCEs for which the theoretical model was developed. 相似文献
679.
Slater Mel Cabriera Carlos Senel Gizem Banakou Domna Beacco Alejandro Oliva Ramon Gallego Jaime 《Virtual Reality》2023,27(2):651-675
Virtual Reality - We created a virtual reality version of a 1983 performance by Dire Straits, this being a highly complex scenario consisting of both the virtual band performance and the appearance... 相似文献
680.
Maria Alp Ramon J. Batalla Maria Dolores Bejarano Isabel Boavida Hervé Capra Mauro Carolli Roser Casas-Mulet Maria João Costa Jo Halvard Halleraker Christoph Hauer Daniel S. Hayes Atle Harby Markus Noack Antoni Palau Matthias Schneider Lennart Schönfelder Diego Tonolla Davide Vanzo Terese Venus Damià Vericat Guido Zolezzi Maria Cristina Bruno 《河流研究与利用》2023,39(3):283-291
An increase in the demand for renewable energy is driving hydropower development and its integration with variable renewable energy sources. When hydropower is produced flexibly from hydropower plants, it causes rapid and frequent artificial flow fluctuations in rivers, a phenomenon known as hydropeaking. Hydropeaking and associated hydrological alterations cause multiple impacts on riverine habitats with cascading effects on ecosystem functioning and structure. Given the significance of its ecological and socio-economic implications, mitigation of hydropeaking requires an inter- and transdisciplinary approach. An interdisciplinary network called HyPeak has been conceived to enrich international research initiatives and support hydropower planning and policy. HyPeak has been founded based on exchange and networking activities linking scientists from several countries where hydropeaking has been widespread for decades and numerous studies dedicated to the topic have been carried out. HyPeak aims to integrate members from other countries and continents in which hydropower production plays a relevant role, and grow to be a reference group that provides expert advice on the topic to policy-makers, as well as researchers, stakeholders, and practitioners in the field of hydropeaking. 相似文献