检索结果-南通市图书馆

催化学报 2011年第11期32卷 1663-1666页

作者： Paolo ZUCCA Antonio RESCIGNO enrico SANJUST Dipartimento di Scienze e Tecnologie Biomediche Università di Cagliari Monserrato 09042 Italy Consorzio per lo Sviluppo dei Sistemi a Grande Interfase Sesto Fiorentino 50019 Italy

A synthetic metalloporphine was immobilized onto a PVA-based and mercapto-grafted solid support, emulating the active site of cytochrome P450. Its ligninolytic peroxidase-like catalytic activity was studied. The coordinated mercapto ligand significantly affected the catalytic features of the catalyst because the oxidation of lignin-model compounds was very slow by comparison with imidazoleand pyridine-coordinated immobilized metalloporphines. Conversely, the catalyst efficiently bleached several industrial dyes and thus demonstrated promising activity for this application. Based on this altered substrate specificity the oxygen-donor catalytic route seems to be more favorable than a single electron oxidation pathway.

关键词： porphine porphyrin lignin peroxidase cytochrome P450 biomimetic

Superlubricity on the nanometer scale

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Friction 2014年第2期2卷 106-113页

作者： Ernst MEYER enrico GNECCO Department of Physics University of BaselKlingelbergstr.824056 BaselSwitzerland IMDEA Nanociencia Campus Universitario de CantoblancoCalle Faraday 928049 MadridSpain

The transition from atomic stick-slip to continuous sliding has been observed in a number of *** extended contacts are moved in different directions,so-called structural lubricity is observed when the two surface lattices are ***,a“superlubric”state of motion can be achieved if the normal force is reduced below a certain threshold,the temperature is increased,or the contact is actuated *** processes have been partially demonstrated using atomic force microscopy,and they can be theoretically understood by proper modifications of the Prandtl−Tomlinson model.

关键词： structural lubricity dynamic superlubricity atomic force microscopy friction force microscopy themolubricity Prandtl−Tomlinson model

GUN4 Is Required for Posttranslational Control of Plant Tetrapyrrole Biosynthesis

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Molecular Plant 2009年第6期2卷 1198-1210页

作者： enrico Peter Bernhard Grimm Institute of Biology/Plant Physiology Humboldt University Philippstr. 13 Building 12 D 10115 Berlin Germany

In aerobic photosynthetic organisms, GUN4 binds the chlorophyll intermediates protoporphyrin and Mg protoporphyrin, stimulates Mg chelatase activity, and is implicated in plastidic retrograde signaling. GUN4 expression is most abundant in young and greening tissues and parallels the activity of 5-aminolevulinic acid （ALA） ALA and Mg porphyrin biosynthesis during photoperiodic growth. We explored function and mode of action of GUN4 using GUN4- deficient and overexpressing plants. GUN4 overexpression leads to a general activation of the enzymes of chlorophyll biosynthesis. During photoperiodic growth GUN4 deficiency prevents ALA synthesis and chlorophyll accumulation. All these metabolic changes do not correlate with altered gene expression or changes of protein abundance in tetrapyrrole biosynthesis. While ALA feeding fails to compensate GUN4 deficiency during light-dark growth, this approach results in chlorophyll accumulation under continuous dim light. A new model defines the involvement of GUN4 in posttranslational regulation of ALA and Mg porphyrin synthesis, to sustain chlorophyll synthesis, namely under varying environmental conditions.

关键词： Tetrapyrrole biosynthesis chlorophyll Mg porphyrin branch photo-oxidation chloroplasts

Advanced modeling of embedded piezo-electric transducers for the health-monitoring of layered structures

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

International Journal of Smart and Nano Materials 2020年第4期11卷 325-342页

作者： enrico Zappino Erasmo Carrera Department of Mechanical and Aerospace Engineering Politecnico di TorinoMul2 Research GroupTorinoItaly

The present paper presents an innovative approach for the numerical modeling of piezo-electric transducers for the health-monitoring of layered *** numerical approach has been developed in the frameworks of the Carrera Unified *** computa-tional tool allows refined numerical models to be derived in a unified and efficient *** use of higher-order models and the cap-ability to connect different kinematic models using the node-depen-dent kinematic approach has led to an efficient modeling technique for global-local *** approach can refine the model only in those regions where it is required,e.g.,the areas where piezo-electric transducers are *** model has been used to study embedded and surface-mounted *** accuracy of the pre-sent model has been verified by comparing the current results with numerical and experimental data from the *** mod-eling solutions have been developed,mixing one-,two-and threedimensional finite *** results show that the use of the present modeling technique allows the computational cost to be reduced with respect to the classical approaches preserving the ccuracy of the results in the critical areas.

关键词： Carrera Unified Formulation Embedded Sensor Health Monitoring Layered Structures Refined models

Reactive pathways toward parasitic release of singlet oxygen in metal-air batteries

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

npj Computational Materials 2021年第1期7卷 1135-1142页

作者： Adriano Pierini Sergio Brutti enrico Bodo Department of Chemistry University of Rome“La Sapienza”RomeItaly GISEL—Centro di Riferimento Nazionale per i Sistemi di Accumulo Elettrochimico di Energia FirenzeItaly

The superoxide disproportionation reaction is a key step in the chemistry of aprotic metal oxygen batteries that controls the peroxide formation upon discharge and opens the way for singlet oxygen *** we clarify the energy landscape of the disproportionation of superoxide in aprotic media catalyzed by group 1A *** analysis is based on ab initio multireference computational methods and unveils the competition between the expected reactive path leading to peroxide and an unexpected reaction channel that involves the reduction of the alkaline *** channels lead to the release of triplet and singlet O_(2).The existence of this reduction channel not only facilitates singlet oxygen release but leads to a reactive neutral solvated species that can onset parasitic chemistries due to their well-known reducing ***,we show that the application of moderate overpotentials makes both these channels accessible in aprotic batteries.

关键词： properties release singlet

Fabrication and Testing of Self Cleaning Dry Adhesives Utilizing Hydrophobicity Gradient

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Journal of Bionic Engineering 2015年第2期12卷 270-275页

作者： enrico Bovcro Jeffrey Krahn Carlo Menon MENRVA Lab School of Engineering Science Simon Fraser University 8888 University Drive Burnaby BC Canada V5A 1S6

In this paper we present a method to create a hydrophobicity gradient on the surface of a Polydimethylsiloxane （PDMS） dry adhesive. The method consists of the partial silanization of the surface of the dry adhesive by Chemical Vapour Deposition （CVD） of octadecyltrichlorosilane （OTS）. The partial silanization of the surface of the sample results in a hydrophobic to hy- drophilic gradient across the surface of the dry adhesive. The resulting change in hydrophobicity across the surface of the dry adhesive results in the uphill motion of a droplet of water, which appears to be directly proportional to the area of contact between the droplet and the adhesive. Normal adhesion testing is performed to quantify the effect of the hydrophobic gradient across the surface of the sample. While a variation in adhesion are only minimally affected by the silanization, and the motion strength across the sample is measured, the adhesive properties of the droplet of water doesn＇t cause any loss of adhesion.

关键词： dry adhesion self cleaning hydrophobic silanization polymers PDMS

A probabilistic model to evaluate the effectiveness of main solutions to COVID-19 spreading in university buildings according to proximity and time-based consolidated criteria

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Building Simulation 2021年第6期14卷 1795-1809页

作者： Marco D'Orazio Gabriele Bernardini enrico Quagliarini Department of Construction Civil Engineering and ArchitectureUniversita Politecnica delle Marchevia Brecce Blanche 60131 AnconaItaly

University buildings are one of the most relevant closed environments in which the COVID-19 event clearly pointed out stakeholders'needs toward safety issues,especially because of the possibility of day-to-day presences of the same users(***,teachers)and overcrowding causing long-lasting contacts with possible"infectors".While waiting for the vaccine,as for other public buildings,policy-makers’measures to limit virus outbreaks combine individual’s strategies(facial masks),occupants,capacity and access ***,up to now,no easy-to-apply tools are available for assessing the punctual effectiveness of such *** fill this gap,this work proposes a quick and probabilistic simulation model based on consolidated proximity and exposure-time-based rules for virus transmission confirmed by international health *** building occupancy is defined according to university scheduling,identifying the main"attraction areas"in the building(classrooms,break-areas).Scenarios are defined in terms of occupants’densities and the above-mentioned mitigation *** model is calibrated on experimental data and applied to a relevant university *** demonstrate the model *** particular,it underlines that if such strategies are not combined,the virus spreading can be limited by only using high protection respiratory devices(***3)by almost every *** the contrary,the combination between access control and building capacity limitation can lead to the adoption of lighter protective devices(*** masks),thus improving the feasibility,users'comfort and favorable *** rules to combine acceptable mask filters-occupants,density are thus provided to help stakeholders in organizing users'presences in the building during the pandemic.

关键词： simulation model closed built environment building occupancy crowd models proximity exposure COVID-19

A review on membrane distillation in process engineering: design and exergy equations, materials and wetting problems

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Frontiers of Chemical Science and Engineering 2022年第5期16卷 592-613页

作者： Stefano Capizzano Mirko Frappa Francesca Macedonio enrico Drioli Institute of Membrane Technology National Research Council of ItalyRende 87036Italy Department of Environmental Engineering University of CalabriaRendeItaly Nanjing Tech University College of Chemical EngineeringNanjing 211816China

One of the problems that most afflicts humanity is the lack of clean *** stress,which is the pressure on the quantity and quality of water resources,exists in many places throughout the *** represents a valid solution to the scarcity of fresh water and several technologies are already well applied and successful(such as reverse osmosis),producing about 100 million m^(3)·d^(-1) of fresh *** advances in the field of desalination can be provided by innovative processes such as membrane *** latter is of particular interest for the treatment of waste currents from conventional desalination processes(for example the retentate of reverse osmosis)as it allows to desalt highly concentrated currents as it is not limited by concentration polarization *** perspectives have enhanced research activities and allowed a deeper understanding of mass and heat transport phenomena,membrane wetting,polarization phenomena and have encouraged the use of materials particularly suitable for membrane distillation *** work summarizes recent developments in the field of membrane distillation,studies for module length optimization,commercial membrane modules developed,recent patents and advancement of membrane material.

关键词： membrane distillation recent developments heat and mass transfer wetting membrane material

Data-driven reliability analysis of Boeing 787 Dreamliner

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Chinese Journal of Aeronautics 2020年第7期33卷 1969-1979页

作者： Guru PANDIAN Michael PECHT enrico ZIO Melinda HODKIEWICZ Center for Advanced Life Cycle Engineering(CALCE) University of MarylandCollege ParkMD 20742USA Department of Energy Politecnico di MilanoItaly Faculty of Engineering and Mathematical Sciences University of Western AustraliaPerthWA 6009Australia

The Boeing 787 Dreamliner,launched in 2011,was presented as a game changer in air *** the aim of producing an efficient,mid-size,wide-body plane,Boeing initiated innovations in product and process design,supply chain operation,and risk ***,there were reliability issues from the start,and the plane was grounded by the *** Aviation Administration(FAA)in 2013,due to safety problems associated with Li-ion battery *** paper chronicles events associated with the aircraft’s initial reliability *** manufacturing,supply chain,and organizational factors that contributed to these problems are assessed based on FAA *** and lessons learned are provided for the benefit of engineers and managers who will be engaged in future complex systems development.

关键词： Boeing 787 Dispatch reliability Dreamliner Lithium-ion battery Reliability Reliability growth

Management of cholelithiasis with choledocholithiasis:Endoscopic and surgical approaches

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

World Journal of Gastroenterology 2021年第28期27卷 4536-4554页

作者： Pasquale Cianci enrico Restini Department of Surgery and Traumatology Hospital Lorenzo BonomoAndria 76123Italy

Gallstone disease and complications from gallstones are a common clinical *** clinical presentation ranges between being asymptomatic and recurrent attacks of biliary pain requiring elective or emergency *** duct stones are a frequent condition associated with *** the total cholecystectomies performed every year for cholelithiasis,the presence of bile duct stones is 5%-15%;another small percentage of these will develop common bile duct stones after *** avoid serious complications that can occur in choledocholithiasis,these stones should be ***,there is no consensus on the ideal management strategy to perform *** a long time,a direct open surgical approach to the bile duct was the only unique *** the advent of advanced endoscopic,radiologic,and minimally invasive surgical techniques,however,therapeutic choices have increased in number,and the management of this pathological situation has become *** date,there is agreement on preoperative management and the need to treat cholelithiasis with choledocholithiasis,but a debate still exists on how to cure the two diseases at the same *** the era of laparoscopy and miniinvasiveness,we can say that therapeutic approaches can be performed in two sessions or in one *** of these two approaches showed equivalent success rates,postoperative morbidity,stone clearance,mortality,conversion to other procedures,total surgery time,and failure rate,but the onesession treatment is characterized by a shorter hospital stay,and more cost *** aim of this review article is to provide the reader with a general summary of gallbladder stone disease in association with the presence of common bile duct stones by discussing their epidemiology,clinical and diagnostic aspects,and possible treatments and their advantages and limitations.

关键词： Gallbladder stones Choledocholithiasis Laparoscopic cholecystectomy Rendezvous technique Management of biliary lithiasis Endoscopic retrograde cholangiopancreatography