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Modeling of Fischer-Tropsch Synthesis in a Slurry Reactor with Water Permeable Membrane

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Journal of Natural Gas Chemistry 2007年第2期16卷 107-114页

作者： fabiano A. N. Fernandes Universidade Federal do Ceara Departamento de Engenharia QuimicaCampus Universitario do PiciBloco 70960455-760 Fortaleza-CEBrazil

Fischer-Tropsch synthesis is an important chemical process for the production of liquid fuels and olefins. In recent years, the abundant availability of natural gas and the increasing demand of olefins, diesel, and waxes have led to a high interest to further develop this process. A mathematical model of a slurry membrane reactor used for syngas polymerization was developed to simulate and compare the maximum yields and operating conditions in the reactor with that in a conventional slurry reactor. The carbon polymerization was studied from a modeling point of view in a slurry reactor with a water permeable membrane and a conventional slurry reactor. Simulation results show that different parameters affect syngas conversion and carbon product distribution, such as the hydrogen to carbon monoxide ratio, and the membrane parameters such as membrane permeance.

关键词： slurry reactor membrane reactor Fischer-Tropsch modeling

Review on the state-of-the-art and challenges in the MgB_(2)component manufacturing for superconducting applications

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Superconductivity 2024年第1期9卷 50-64页

作者： fabiano Carvalho de Castro Sene Department of Industrial and Systems Engineering University of TennesseeKnoxvilleUnited States

Since the discovery of MgB_(2)as a superconductor,several research groups worldwide have studied the superconducting mechanisms due to the dual gap nature of MgB_(2),as well as attempted to produce such a compound in wires,tapes,bulks,and thin films for a plethora of *** MgB_(2)carries the promise of replacing Niobium‐based superconductors in low‐field applications,less‐than‐desirable performance and in‐operation stability has slowed down such a *** the properties and nature of the superconductivity of MgB_(2)are fairly known,the reproduction of its properties at manufacturing scales remains an unsolved ***,this manuscript presents a systematic review on fundamental properties,phase formation,growth kinetics,and superconducting properties of MgB_(2)‐based components such as multi‐and mono‐core wires,bulks,and thin ***,challenges,and shortcomings are utilized in consolidating research questions and directions pertaining to the manufacturing of MgB_(2)superconducting ***,we evaluate the technological readiness of MgB_(2)‐based devices for applications in fusion energy systems.

关键词： MgB_(2) Superconductor manufacturing Technology readiness Review Low‐Field applications

Forecast electricity demand in commercial building with machine learning models to enable demand response programs

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Energy and AI 2022年第1期7卷 18-30页

作者： fabiano Pallonetto Changhong Jin Eleni Mangina School of Computer Science University College DublinIreland School of Business Maynooth UniversityIreland

Electricity load forecasting is an important part of power system *** forecasting electricity load have great impact on a number of departments in power *** to electricity load simulation(white-box model),electricity load forecasting(black-box model)does not require expertise in building *** development cycle of the electricity load forecasting model is much shorter than the design cycle of the electricity load *** developments in machine learning have lead to the creation of models with strong fitting and accuracy to deal with nonlinear *** on the real load dataset,this paper evaluates and compares the two mainstream short-term load forecasting *** the experiment,this paper first enumerates the common methods of short-term load forecasting and explains the principles of Long Short-term Memory Networks(LSTMs)and Support Vector Machines(SVM)used in this ***,based on the characteristics of the electricity load dataset,data pre-processing and feature selection takes *** paper describes the results of a controlled experiment to study the importance of feature *** LSTMs model and SVM model are applied to one-hour ahead load forecasting and one-day ahead peak and valley load *** predictive accuracy of these models are calculated based on the error between the actual and predicted loads,and the runtime of the model is *** results show that the LSTMs model have a higher prediction accuracy when the load data is ***,the overall performance of the SVM model is better when the load data used to train the model is insufficient and the time cost is prioritized.

关键词： Deep neural network Model assessment Short-term load forecasting Feature selection Support Vector Machines Artificial Neural Networks Long Short-term Memory Networks Demand response

Sorbents with high efficiency for CO2 capture based on amines-supported carbon for biogas upgrading

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Journal of Environmental Sciences 2016年第10期28卷 138-150页

作者： Lidia Pino Cristina Italiano Antonio Vita Concetto fabiano Vincenzo Recupero CNR Institute of Aduanced Technology for Energy "Nicola Giordano" Via S. Lucia 5 98126 Messina Italy

Sorbents for CO2 capture have been prepared by wet impregnation of a commercial active carbon （Ketjen-black, Akzo Nobel） with two CO2-philic compounds, polyethylenimine （PEI） and tetraethylenepentamine （TEPA）, respectively. The effects of amine amount （from 10 to 70 wt.%）, CO2 concentration in the feed, sorption temperature and gas hourly space velocity on the CO2 capture performance have been investigated. The sorption capacity has been evaluated using the breakthrough method, with a fixed bed reactor equipped with on line gas chromatograph. The samples have been characterized by N2 adsorption-desorption, scanning electron microscopy and energy dispersive X-ray （SEM/EDX）. A promising CO2 sorption capacity of 6.90 mmo1/gsorbent has been obtained with 70 wt.% of supported TEPA at 70℃ under a stream containing 80 vol% of CO2. Sorption tests, carried out with simulated biogas compositions （CH4/CO2 mixtures）, have revealed an appreciable CO2 separation selectivity; stable performance was maintained for 20 adsorption-desorption cycles.

关键词： CO2 capturePEI-TEPA based sorbentsAmine efficiencyBiogasSeparation selectivity

Divergent DNA Methylation Patterns Associated with Abiotic Stress in Hevea brasiliensis

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Molecular Plant 2011年第6期4卷 996-1013页

作者： Thomas K. Uthup Minimol Ravindran, K. bini Saha Thakurdas Genome Analysis Lab Rubber Research Institute of India Rubber Board PO Kottayam Kerala 686009 India

Cytosine methylation is a fundamental epigenetic mechanism for gene-expression regulation and development in plants. Here, we report for the first time the identification of DNA methylation patterns and their putative relationship with abiotic stress in the tree crop Hevea brasiliensis （source of 99% of natural rubber in the world）. Regulatory sequences of four major genes involved in the mevalonate pathway （rubber biosynthesis pathway） and one general defense-related gene of three high-yielding popular rubber clones grown at two different agroclimatic conditions were analyzed for the presence of methylation. We found several significant variations in the methylation pattern at core DNA binding motifs within all the five genes. Several consistent clone-specific and location-specific methylation patterns were identified. The differences in methylation pattern observed at certain pivotal cis-regulatory sites indicate the direct impact of stress on the genome and support the hypothesis of site-specific stress-induced DNA methylation. It is assumed that some of the methylation patterns observed may be involved in the stress-responsive mechanism in plants by which they adapt to extreme conditions. The study also provide clues towards the existence of highly divergent phenotypic characters among Hevea clones despite their very similar genetic make-up. Altogether, the observations from this study prove beyond doubt that there exist epigenetic variations in Hevea and environmental factors play a significant role in the induction of site-specific epigenetic mutations in its genome.

关键词： DNA methylation epigenetics abiotic stress rubber biosynthesis Hevea brasiliensis.

Highly degradable chitosan-montmorillonite (MMT) nanocomposite hydrogel for controlled fertilizer release

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Frontiers of Environmental Science & Engineering 2023年第5期17卷 1-11页

作者： Zeou Dou Maria Vitoria bini Farias Wensi Chen Dongjing He Yuhang Hu Xing Xie School of Civil and Environmental Engineering Georgia Institute of TechnologyAtlantaGA 30332USA George W.Woodruff School of Mechanical Engineering Georgia Institute of TechnologyAtlantaGA 30332USA School of Chemical and Biomolecular Engineering Georgia Institute of TechnologyAtlantaGA 30332USA

Fertilizer consumption is increasing drastically along with the rapid expansion of farming in response to the ever-growing population. However, a significant portion of the nutrients in traditional fertilizers is lost during leaching and runoff causing economic loss and environmental threats. Polymer-modified controlled-release fertilizers provide an opportunity for mitigating adverse environmental effects and increasing the profitability of crop production. Here, we present a cheap and easy-to-fabricate controlled-release fertilizer excipient based on hydrogels scaffolded by safe and biodegradable chitosan and montmorillonite (MMT) nanoclays. By introducing elastic and flexible physical crosslinking induced by 2-dimensional (2D) MMT nanoflakes into the chitosan hydrogel, highly swellable and degradable chitosan-MMT nanocomposites were fabricated. The addition of MMT into the chitosan hydrogels enhanced the total release of phosphorous (P) and potassium (K), from 22.0 % to 94.9 % and 9.6% to 31.4 %, respectively, compared to the pure chitosan gel. The chitosan-MMT nanocomposite hydrogel achieved a well-controlled overall fertilizer release in soil. A total of 55.3 % of loaded fertilizer was released over 15 d with a daily release of 2.8 %. For the traditional fertilizer podwer, 89.2 % of the fertilizer was washed out during the first irrigation under the same setup. In the meantime, the nanocomposites improved the water retention of the soil, thanks to its excellent water absorbency. Moreover, the chitosan-MMT nanocomposite hydrogels exhibited high degradation of 57 % after swelling in water for 20 d. Such highly degradable fertilizer excipient poses minimal threat to the long-term fertility of the soil. The engineered Chitosan-MMT biopolymer scaffold as a controlled-release fertilizer excipient provides a promising opportunity for advancing sustainable agriculture.

关键词： Biopolymer Hydrogel Controlled-release fertilizer Nanoclay Nanocomposite

Chemical strategies and biomedical applications of DNA hydrogels

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Fundamental Research 2023年第4期3卷 534-536页

作者： bini Zhou Cuifeng Li Dongsheng Liu Wanli Liu Key Laboratory of Bioorganic Phosphorus Chemistry and Chemical Biology Department of ChemistryTsinghua UniversityBeijing 100084China State Key Laboratory of Membrane Biology School of Life SciencesInstitute for ImmunologyBeijing Advanced Innovation Center for Structural BiologyCollaborative Innovation Center for Diagnosis and Treatment of Infectious DiseasesBeijing Key Lab for Immunological Research on Chronic DiseasesTsinghua UniversityBeijing 100084China Tsinghua-Peking Center for Life Sciences Beijing 100084China

*** Deoxyribonucleic acid(DNA)is a digital polymer that,in addition to being the carrier of genetic information in biological systems,can also act as building blocks for the fabrication of *** accordance with the rapid development of DNA synthesis technologies,DNA has also been utilized as a fantastic type of brick for the construction of sophisticated supramolecular materials,especially DNA *** to its favorable biocompatibility and designable responsiveness,there have been emerging efforts to demonstrate the application of DNA hydrogels in biomedicine,with encouraging ***,we highlight the recent advances of chemical strategies and biomedical applications of DNA hydrogels.

关键词： hydrogel utilized synthesis

Effect of operating conditions and potassium content on Fischer-Tropsch liquid products produced by potassium-promoted iron catalysts

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Journal of Natural Gas Chemistry 2008年第2期17卷 175-178页

作者： Francisco E.M.Farias Fernando G.Sales fabiano A.N.Fernandes Universidade Federal do Ceará Departamento de Engenharia QuímicaCampus do PiciBloco 70960455-760 Fortaleza-CEBrazil

The dependencies of Fischer-Tropsch synthesis liquid hydrocarbon product distribution on operating pressure and temperature have been studied over three potassium-promoted iron catalysts with increasing potassium molar content. The study followed an experimental planning and the results were analyzed based on surface response methodology. The effects of different operating conditions and potassium contents on the liquid product distribution were compared based on number average carbon number and dispersion. Results showed that high pressures （25 to 30 arm） favored the production of waxes that could be converted into liquid fuels through hydrocracking, while greater direct selectivity towards diesel was favored by low pressure （20 arm） using catalysts with low potassium to iron molar ratios. The liquid product distribution produced using an iron catalyst with high potassium content presented higher number-average number of carbons when compared to the distribution obtained using an iron catalyst with low potassium content.

关键词： Fischer-Tropsch synthesis liquid fuels iron-based catalyst potassium

Bismuth oxide-related photocatalysts in green nanotechnology:A critical analysis

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Frontiers of Chemical Science and Engineering 2018年第4期12卷 878-892页

作者： Andrea P.Reverberi P.S.Varbanov M.Vocciante B.fabiano Department of Chemistry and Industrial Chemistry Genoa University16146 GenoaItaly Pazmany Peter Catholic University Faculty of Information Technology and Bionics1083 BudapestHungary Department of Civil Chemical and Environmental EngineeringPolytechnic SchoolGenoa University16145 GenoaItaly

A survey addressing the uses of bismuth oxide in photocatalysis is presented. The richness of literature on such a specific topic proves the growing importance of this compound as a valid tool in pollution abatement and environmental decontamination. Many research groups have focused their activity on how to improve the photocatalytic properties of this semiconductor and several solutions have been adopted in the synthesis method, often based on wet-chemical processes. The impressive development of nanoscience helped in understanding and identifying process variables and operative conditions aiming at optimizing the yield of this promising photocatalytic material in the utilization of solar energy.

关键词： photocatalysis visible light bismuth compounds nanotechnology environmental remediation decontamination pollution abatement