Gli autori estendono il loro apprezzamento al dottor Thomas J. Emge e Wei Liu dell&#39;Università Rutgers per la loro analisi e la loro esperienza nella diffrazione a raggi X a piccole angolazioni e nella diffrazione a raggi X in polvere. Inoltre, gli autori riconoscono Hao Wang per il suo supporto con gli esperimenti di adsorbimento N 2 .

1. Sintesi di Al (OH) 3 Nanoparticle <ol><li> Sciogliere 1,40 g di esaliduro di cloruro di alluminio in 5,822 g di acqua deionizzata. </li><li> Aggiungere 2,778 g di L-arginina alla soluzione acquosa di cloruro di alluminio sotto agitazione magnetica. Aggiungere lentamente l&#39;L-arginina, in modo che l&#39;arginina aggiunta si scioglie e non forma grossi frammenti o frammenti; Inoltre, un&#39;aggiunta lenta riduce le concentrazioni locali di alcalinità e fornisce condizioni per un&#39;idrolisi più controllabile. </li><li> Una volta che tutta l&#39;arginina si scioglie nella soluzione, scaldare la soluzione per 72 h a 50 ° C; A questo punto, la soluzione può apparire come una sospensione nuvolosa. </li></ol> 2. Precipitare Al (OH) 3 con NaCl <ol><li> Preparare una colonna GPC che è di 49 in lunghezza e 1.125 di diametro. Imballare il gel in passi successivi di aggiunta di gel e consentendo l&#39;acqua di fluire attraverso la colonna per garantire l&#39;imballaggio corretto, con uno spazio minimo tra le perle di gel. Imballare laGel a circa l&#39;80% della colonna; La quantità di gel imballato varia ogni volta e influenza solo il tempo di ritenzione della specie separata. </li><li> Introdurre 10 ml di sospensione di nanoparticelle sintetizzata (sintetizzata) al (OH) 3 (preparata al punto 1.3) nella colonna utilizzando una pompa HPLC con un anello iniettore da 10 ml. Personalizzare il ciclo dell&#39;iniettore utilizzando tubi con un diametro esterno di circa 0,125 in e una lunghezza calibrata per fornire 10 ml di campione iniettato. </li><li> Raccogliere l&#39;eluizione della colonna in intervalli correlati con la posizione del picco dRI. Collegare l&#39;uscita GPC all&#39;ingresso di un rivelatore differenziale differenziale (dRI). NOTA: quando le specie separate escono dal GPC, appaiono sul rivelatore dRI come picco e vengono raccolte in bottiglie da 125 ml. La colonna GPC produce due picchi ben risolti, entrambi raccolti e analizzati con cromatografia di esclusione di dimensioni (SEC) e analisi elementare (EA) per discernere l&#39;arginina da speCies. Il volume totale raccolto dipenderà dalla dimensione della colonna GPC, dalla quantità totale del materiale di imballaggio utilizzato e dalla portata dell&#39;acqua deionizzata usata per eluire la colonna. <ol><li> Raccogliere la maggior parte della frazione di picco 1 per 100 min ad una portata di 0,2 mL / min. </li><li> Raccogliere l&#39;eluente in intervalli di 30 minuti una volta che un picco emerge sul rivelatore RI della colonna GPC. NOTA: la variazione dell&#39;intervallo di intervallo cambierà la concentrazione e la purezza del materiale di punta 1 purificato risultante. È meglio raccogliere all&#39;inizio piccoli intervalli di picco per determinare quale parte contiene la concentrazione e la purezza più alte della specie di picco per una colonna specifica. </li></ol></li><li> Preparare 1% in peso di NaCl. </li><li> Aggiungere la soluzione NaCl preparata in goccia a 10 ml di nanoparticelle Al (OH) 3 purificate; Il materiale preparato con precipitazione NaCl non viene utilizzato per ulteriori esperimenti. </li></ol> 3. Preparazione di Al-MCM-41 <ol><li> ACPortare circa 1,0 g di MCM-41 a 120 ° C sotto vuoto per 3 ore in un forno a vuoto. </li><li> Preparare 50,0 g di soluzione di cloruro di alluminio combinando 9,6926 g di AlCl 3 · 6H 2 O con 40,3074 g di acqua deionizzata. </li><li> Aggiungere 0,7 g di MCM-41 attivato a 50,0 g di soluzione di cloruro di alluminio (preparato al punto 3.2). </li><li> Consentire un adeguato tempo di miscelazione (1 h) per garantire l&#39;omogeneità dell&#39;AlCl 3 diffuso in tutti i canali MCM-41. </li><li> Aggiungere L-arginina alla miscela eterogenea ad un rapporto molare Arg / Al di 2,75 sotto agitazione magnetica. Similmente al punto 1.2, aggiungere l&#39;arginina abbastanza lentamente in modo da consentire ai flocculati istantanei di formarsi e ridurre il clumping dell&#39;arginina prima di continuare l&#39;aggiunta. </li><li> Una volta omogenea, scaldare la miscela a 50 ° C per 72 ore. </li><li> Filtrare la soluzione eterogenea ottenuta utilizzando un imbuto di Buchner sotto vuoto e dotato di cerchi di carta di filtrazione qualitativa da 90 mm(O qualsiasi altra carta filtro appropriata). </li><li> Lavare la polvere bianca filtrata con acqua eccessiva deionizzata per assicurare la rimozione di cloruro di alluminio non reagito, arginina o sottoprodotti solubili in acqua dal materiale Al-MCM-41 prodotto. </li></ol>

<ol>
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La preparazione di una soluzione acquosa di cloruro di alluminio ha comportato l&#39;impiego di un sale esahidrato cristallino di cloruro di alluminio. Anche se la forma anidro può essere utilizzata, non è preferibile a causa delle sue proprietà igroscopiche significative, che rendono difficile lavorare e controllare la concentrazione di alluminio. È opportuno notare che la soluzione di cloruro di alluminio deve essere impiegata entro diversi giorni dalla preparazione perché nel corso del tempo l&#39;idrolysere [Al...

I materiali realizzati in idrossido di alluminio sono promettenti candidati per una varietà di applicazioni industriali, tra cui la catalisi, i prodotti farmaceutici, il trattamento dell&#39;acqua e la cosmetica. 1 , 2 , 3 , 4 A temperature elevate, l&#39;idrossido di alluminio assorbe una notevole quantità di calore durante la decomposizione per produrre l&#39;allumina (Al 2 O 3 ), rendendolo un utile agente di ritardamento della fiamma. 5 I quattro polimorfi noti di idrossido di alluminio ( es . Gibbsite, bayerite, nordstrandite e doyleite) sono stati studiati usando tecniche computazionali e sperimentali per migliorare la nostra comprensione della formazione e delle sue strutture 6 . La preparazione di particelle di nanoscala è di particolare interesse a causa del loro potenziale per esibire effetti quantistici e proprietà differenti da quelle diR controparti di massa. Le particelle Nanogibbsite con dimensioni all&#39;ordine di 100 nm sono facilmente preparabili in varie condizioni 7 , 8 , 9 , 10 , 11 , 12 , 13 , 14 . Superare le sfide intrinseche associate a ridurre ulteriormente le dimensioni delle particelle è difficile; Quindi, esistono solo pochi casi in cui le particelle nanogibbsite hanno dimensioni sull&#39;ordine di 50 nm. 14 , 15 , 16 , 17 Secondo le nostre conoscenze, non ci sono stati resoconti di nanogibbsite particelle inferiori a 50 nm. In parte, questo è attribuito al fatto che le nanoparticelle tendono ad agglomerare a causa dell&#39;instabilità elettrostaticaE l&#39;alta probabilità per la formazione di legami di idrogeno tra le particelle colloidali, in particolare nei solventi prototipali polari. Il nostro obiettivo era quello di sintetizzare piccole nanoparticelle di Al (OH) 3 utilizzando esclusivamente ingredienti e precursori sicuri. Nel lavoro in corso, l&#39;aggregazione di particelle acquose è stata inibita incorporando un aminoacido ( ossia L-arginina) come tampone e stabilizzatore. Inoltre, è stato riferito che l&#39;arginina contenente guanidina impediva la crescita e l&#39;aggregazione di particelle di idrossido di alluminio per ottenere una sospensione colloidale acquosa con dimensioni medie di 10-30 nm. Si propone qui che le proprietà amfoteriche e zwitterioniche dell&#39;arginina hanno mitigato la carica superficiale delle nanoparticelle di idrossido di alluminio durante l&#39;idrolisi lieve per disfare la crescita delle particelle oltre i 30 nm. Sebbene l&#39;arginina non fosse in grado di ridurre la dimensione di particelle inferiore a 10 nm, tali particelle sono state ottenute sfruttando l&#39;effetto di confinamento &quot;gabbia&quot;Hin i mesopori di MCM-41. La caratterizzazione del materiale composito Al-MCM-41 ha rivelato le nanoparticelle ultrafine di idrossido di alluminio all&#39;interno della silice mesoporosa, che ha una dimensione media di pori di 2,7 nm.

<table><tbody><tr><td>aluminum chloride hexahydrate</td><td>Alfa Aesar</td><td>12297</td><td></td></tr><tr><td>L-arginine</td><td>BioKyowa</td><td>N/A</td><td></td></tr><tr><td>aluminum hydroxide</td><td>Sigma Aldrich</td><td>239186</td><td></td></tr><tr><td>Bio-Gel P-4 Gel</td><td>Bio-Rad</td><td>150-4128</td><td></td></tr><tr><td>Mesoporous siica (MCM-41 type)</td><td>Sigma Aldrich</td><td>643645</td><td></td></tr></tbody></table>

facile preparation of ultrafine aluminum hydroxide particles with or without mesoporous mcm-41 in ambient environments

Una sospensione acquosa di nanogibbsite è stata sintetizzata mediante la titolazione di acido di acido di alluminio [Al (H 2 O) 6 ] 3+ con L-arginina a pH 4.6. Dal momento che l&#39;idrolisi dei sali di alluminio acquoso è noto per produrre una vasta gamma di prodotti con un&#39;ampia gamma di distribuzioni di dimensioni, una varietà di strumenti all&#39;avanguardia ( cioè 27 Al / 1 H NMR, FTIR, ICP-OES , TEM-EDX, XPS, XRD e BET) sono stati utilizzati per caratterizzare i prodotti di sintesi e l&#39;identificazione dei sottoprodotti. Il prodotto, che era costituito da nanoparticelle (10-30 nm), è stato isolato utilizzando la tecnica della colonna di permeazione di cromatografia gel (GPC). La spettroscopia a raggi infrarossi (FTIR) di trasformazione di Fourier e la diffrazione a raggi X della polvere (PXRD) hanno identificato il materiale purificato come polimorfo di gibbsite di idrossido di alluminio. L&#39;aggiunta di sali inorganici ( es . NaCl) ha indotto la destabilizzazione elettrostatica della sospensione, agglomerando così le nanoparticelle a yieLd Al (OH) 3 precipitato con grandi particelle. Utilizzando il nuovo metodo sintetico qui descritto, Al (OH) 3 è stato parzialmente caricato all&#39;interno del quadro mesoporoso altamente ordinato di MCM-41, con dimensioni medie piana di 2,7 nm, producendo un materiale aluminosilicato con entrambe l&#39;ottaedra e tetraedrica Al (O h / T d = 1,4). Il contenuto totale di Al, misurato utilizzando spettrometria a raggi X dispersivi a energia (EDX), era dell&#39;11% w / w con un rapporto molare Si / Al di 2.9. Un confronto di bulk EDX con l&#39;analisi elementare di spettroscopia a raggi X a raggi X (XPS) ha fornito informazioni sulla distribuzione di Al all&#39;interno del materiale aluminosilicato. Inoltre, sulla superficie esterna (3.6) è stato osservato un più alto rapporto di Si / Al rispetto alla massa (2.9). L&#39;approssimazione dei rapporti O / Al suggerisce una maggiore concentrazione di gruppi Al (O) 3 e Al (O) 4 , vicino al nucleo e alla superficie esterna, rispettivamente. La nuova sintesi di Al-MCM-41 produce una reElevato contenuto Al mantenendo l&#39;integrità della struttura silicea ordinata e può essere utilizzata per applicazioni in cui le nanoparticelle di Al 2 O 3 idrate o anidro sono vantaggiose.

Sintesi Nanogibbsite Nanogibbsite è stato preparato titolando AlCl 3 · 6H 2 O (14% in peso) con L-arginina ad un rapporto finale molare Arg / Al di 2,75. La sintesi delle particelle nanogibbsite è stata monitorata tramite SEC, una tecnica di analisi ampiamente utilizzata per soluzioni di cloruro di alluminio parzialmente idrolizzato, in grado di individuare cinque domini arbitrariamente designati...

Watch this Scientific Journal Video about Facile Preparation of Ultrafine Aluminum Hydroxide Particles with or without Mesoporous MCM-41 in Ambient Environments at JoVE.com

Facile Preparation of Ultrafine Aluminum Hydroxide Particles with or without Mesoporous MCM-41 in Ambient Environments

Una sospensione di nanoparticelle di idrossido di alluminio ultrafine è stata preparata tramite la titolazione controllata di Al (H 2 O) 3+ con L-arginina a pH 4.6 con e senza confini di gabbia all&#39;interno di canali mesoporosi di MCM-41.

Facile preparazione di particelle ultra-fine di idrossido di alluminio con o senza MCP-41 mesoporous in ambienti ambientali

An aqueous suspension of nanogibbsite was synthesized via the titration of aluminum aqua acid [Al(H2O)6]3+ with L-arginine to pH 4.6. Since the hydrolysis ...

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10.8K Views.  Colgate-Palmolive Company.  Una sospensione di nanoparticelle di idrossido di alluminio ultrafine è stata preparata tramite la titolazione controllata di Al (H 2 O) 3+ con L-arginina a pH 4.6 con e senza confini di gabbia all'interno di canali mesoporosi di MCM-41. 

Video: Facile Preparation of Ultrafine Aluminum Hydroxide Particles with or without Mesoporous MCM-41 in Ambient Environments

Ultrahigh Density Array of Vertically Aligned Small-molecular Organic Nanowires on Arbitrary Substrates

In recent years &pi;-conjugated organic semiconductors have emerged as the active material in a number of diverse applications including large-area, low-cost displays, photovoltaics, printable and flexible electronics and organic spin valves. Organics allow (a) low-cost, low-temperature processing and (b) molecular-level design of electronic, optical and spin transport characteristics. Such features are not readily available for mainstream inorganic semiconductors, which have enabled organics to carve a niche in the silicon-dominated electronics market. The first generation of organic-based devices has focused on thin film geometries, grown by physical vapor deposition or solution processing. However, it has been realized that organic nanostructures can be used to enhance performance of above-mentioned applications and significant effort has been invested in exploring methods for organic nanostructure fabrication.	
A particularly interesting class of organic nanostructures is the one in which vertically oriented organic nanowires, nanorods or nanotubes are organized in a well-regimented, high-density array. Such structures are highly versatile and are ideal morphological architectures for various applications such as chemical sensors, split-dipole nanoantennas, photovoltaic devices with radially heterostructured "core-shell" nanowires, and memory devices with a cross-point geometry. Such architecture is generally realized by a template-directed approach. In the past this method has been used to grow metal and inorganic semiconductor nanowire arrays. More recently &pi;-conjugated polymer nanowires have been grown within nanoporous templates. However, these approaches have had limited success in growing nanowires of technologically important &pi;-conjugated small molecular weight organics, such as tris-8-hydroxyquinoline aluminum (Alq3), rubrene and methanofullerenes, which are commonly used in diverse areas including organic displays, photovoltaics, thin film transistors and spintronics.	
Recently we have been able to address the above-mentioned issue by employing a novel "centrifugation-assisted" approach. This method therefore broadens the spectrum of organic materials that can be patterned in a vertically ordered nanowire array. Due to the technological importance of Alq3, rubrene and methanofullerenes, our method can be used to explore how the nanostructuring of these materials affects the performance of aforementioned organic devices. The purpose of this article is to describe the technical details of the above-mentioned protocol, demonstrate how this process can be extended to grow small-molecular organic nanowires on arbitrary substrates and finally, to discuss the critical steps, limitations, possible modifications, trouble-shooting and future applications.

We report a simple method for fabricating an ultrahigh density array of vertically ordered small-molecular organic nanowires. This method allows for synthesis of complex heterostructured hybrid nanowire geometries, which can be inexpensively grown on arbitrary substrates. These structures have potential applications in organic electronics, optoelectronics, chemical sensing, photovoltaics and spintronics.

Altissima densità Array of allineato verticalmente Nanofili organici piccola molecolari su substrati arbitrarie

In  recent years &pi;-conjugated  organic semiconductors have emerged as the active material in a number of  diverse applications including large-area, ...

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Two-way Valorization of Blast Furnace Slag: Synthesis of Precipitated Calcium Carbonate and Zeolitic Heavy Metal Adsorbent

The aim of this work is to present a zero-waste process for storing CO2 in a stable and benign mineral form while producing zeolitic minerals with sufficient heavy metal adsorption capacity. To this end, blast furnace slag, a residue from iron-making, is utilized as the starting material. Calcium is selectively extracted from the slag by leaching with acetic acid (2 M CH3COOH) as the extraction agent. The filtered leachate is subsequently physico-chemically purified and then carbonated to form precipitated calcium carbonate (PCC) of high purity (&lt;2 wt% non-calcium impurities, according to ICP-MS analysis). Sodium hydroxide is added to neutralize the regenerated acetate. The morphological properties of the resulting calcitic PCC are tuned for its potential application as a filler in papermaking. In parallel, the residual solids from the extraction stage are subjected to hydrothermal conversion in a caustic solution (2 M NaOH) that leads to the predominant formation of a particular zeolitic mineral phase (detected by XRD), namely analcime (NaAlSi2O6&#8729;H2O). Based on its ability to adsorb Ni2+, as reported from batch adsorption experiments and ICP-OES analysis, this product can potentially be used in wastewater treatment or for environmental remediation applications.

A protocol for the parallel production of precipitated calcium carbonate and zeolitic material from blast furnace slag via mineral carbonation and alkaline hydrothermal conversion, respectively, is presented. The performance of the zeolitic material towards nickel adsorption is tested.

Bidirezionale Valorizzazione di scorie d&#39;altoforno: Sintesi di carbonato di calcio precipitato e zeolitici Heavy Metal Adsorbente

The aim of this work is to present a zero-waste process for storing CO2 in a stable and benign mineral form while producing zeolitic minerals with ...

Simultaneous Multi-surface Anodizations and Stair-like Reverse Biases Detachment of Anodic Aluminum Oxides in Sulfuric and Oxalic Acid Electrolyte

After reporting on the two-step anodization, nanoporous anodic aluminum oxides (AAOs) have been widely utilized in the versatile fields of fundamental sciences and industrial applications owing to their periodic arrangement of nanopores with relatively high aspect ratio. However, the techniques reported so far, which could be only valid for mono-surface anodization, show critical disadvantages, i.e., time-consuming as well as complicated procedures, requiring toxic chemicals, and wasting valuable natural resources. In this paper, we demonstrate a facile, efficient, and environmentally clean method to fabricate nanoporous AAOs in sulfuric and oxalic acid electrolytes, which can overcome the limitations that result from conventional AAO fabricating methods. First, plural AAOs are produced at one time through simultaneous multi-surfaces anodization (SMSA), indicating mass-producibility of the AAOs with comparable qualities. Second, those AAOs can be separated from the aluminum (Al) substrate by applying stair-like reverse biases (SRBs) in the same electrolyte used for the SMSAs, implying simplicity and green technological characteristics. Finally, a unit sequence consisting of the SMSAs sequentially combined with SRBs-based detachment can be applied repeatedly to the same Al substrate, which reinforces the advantages of this strategy and also guarantees the efficient usage of natural resources.

A protocol for fabricating nanoporous anodic aluminum oxides via simultaneous multi-surfaces anodization followed by stair-like reverse biases detachments is presented. It can be applied repeatedly to the same aluminum substrate, exhibiting a facile, high-yield, and environmentally clean strategy.

Anodizations multi-superficie simultanea e pregiudizi inversa scala-come distaccamento di ossidi di alluminio anodico in solforico e acido ossalico elettrolita

After reporting on the two-step anodization, nanoporous anodic aluminum oxides (AAOs) have been widely utilized in the versatile fields of fundamental ...

Fabrication and Testing of Catalytic Aerogels Prepared Via Rapid Supercritical Extraction

Protocols for preparing and testing catalytic aerogels by incorporating metal species into silica and alumina aerogel platforms are presented. Three preparation methods are described: (a) the incorporation of metal salts into silica or alumina wet gels using an impregnation method; (b) the incorporation of metal salts into alumina wet gels using a co-precursor method; and (c) the addition of metal nanoparticles directly into a silica aerogel precursor mixture. The methods utilize a hydraulic hot press, which allows for rapid (&#60;6 h) supercritical extraction and results in aerogels of low density (0.10 g/mL) and high surface area (200-800 m2/g). While the work presented here focuses on the use of copper salts and copper nanoparticles, the approach can be implemented using other metal salts and nanoparticles. A protocol for testing the three-way catalytic ability of these aerogels for automotive pollution mitigation is also presented. This technique uses custom-built equipment, the Union Catalytic Testbed (UCAT), in which a simulated exhaust mixture is passed over an aerogel sample at a controlled temperature and flow rate. The system is capable of measuring the ability of the catalytic aerogels, under both oxidizing and reducing conditions, to convert CO, NO and unburned hydrocarbons (HCs) to less harmful species (CO2, H2O and N2). Example catalytic results are presented for the aerogels described.

Here we present protocols for preparing and testing catalytic aerogels by incorporating metal species into silica and alumina aerogel platforms. Methods for preparing materials using copper salts and copper-containing nanoparticles are featured. Catalytic testing protocols demonstrate the effectiveness of these aerogels for three-way catalysis applications.

Fabbricazione e collaudo di aerogel catalitico preparato tramite rapida estrazione supercritica

Protocols for preparing and testing catalytic aerogels by incorporating metal species into silica and alumina aerogel platforms are presented. Three ...

Chimica

Growth and Electrostatic/chemical Properties of Metal/LaAlO3/SrTiO3 Heterostructures

The quasi 2D electron system (q2DES) that forms at the interface between LaAlO3 (LAO) and SrTiO3 (STO) has attracted much attention from the oxide electronics community. One of its hallmark features is the existence of a critical LAO thickness of 4 unit-cells (uc) for interfacial conductivity to emerge. Although electrostatic mechanisms have been proposed in the past to describe the existence of this critical thickness, the importance of chemical defects has been recently accentuated. Here, we describe the growth of metal/LAO/STO heterostructures in an ultra-high vacuum (UHV) cluster system combining pulsed laser deposition (to grow the LAO), magnetron sputtering (to grow the metal) and X-ray photoelectron spectroscopy (XPS). We study step by step the formation and evolution of the q2DES and the chemical interactions that occur between the metal and the LAO/STO. Additionally, magnetotransport experiments elucidate on the transport and electronic properties of the q2DES. This systematic work not only demonstrates a way to study the electrostatic and chemical interplay between the q2DES and its environment, but also unlocks the possibility to couple multifunctional capping layers with the rich physics observed in two-dimensional electron systems, allowing the fabrication of new types of devices.

Growth and Electrostatic/chemical Properties of Metal/LaAlO3/SrTiO3 Heterostructures

We fabricate metal/LaAlO3/SrTiO3 heterostructures using a combination of pulsed laser deposition and in situ magnetron sputtering. Through magnetotransport and in situ X-ray photoelectron spectroscopy experiments, we investigate the interplay between electrostatic and chemical phenomena of the quasi two-dimensional electron gas formed in this system.

Crescita ed elettrostatico/chimica proprietà di metallo/LaAlO3/SrTiO3 eterostrutture

The quasi 2D electron system (q2DES) that forms at the interface between LaAlO3 (LAO) and SrTiO3 (STO) has attracted much attention from the oxide ...

Multiscale Structures Aggregated by Imprinted Nanofibers for Functional Surfaces

Multiscale surface structures have attracted increasing interest owing to several potential applications in surface devices. However, an existing challenge in the field is the fabrication of hybrid micro-nano structures using a facile, cost-effective, and high-throughput method. To overcome these challenges, this paper proposes a protocol to fabricate multiscale structures using only an imprint process with an anodic aluminum oxide (AAO) filter and an evaporative self-aggregation process of nanofibers. Unlike previous attempts that have aimed to straighten nanofibers, we demonstrate a unique fabrication method for multiscale aggregated nanofibers with high aspect ratios. Furthermore, the surface morphology and wettability of these structures on various liquids were investigated to facilitate their use in multifunctional surfaces.

Presented is an easy method to fabricate nano-micro multiscale structures, for functional surfaces, by aggregating nanofibers fabricated using an anodic aluminum oxide filter.

Multiscala strutture aggregate da nanofibre impresse per superfici funzionali

Multiscale surface structures have attracted increasing interest owing to several potential applications in surface devices. However, an existing ...

A Continuous-flow Photocatalytic Reactor for the Precisely Controlled Deposition of Metallic Nanoparticles

In this work, a novel photocatalytic reactor for the pulsed and controlled excitation of the photocatalyst and the precise deposition of metallic nanoparticles is developed. Guidelines for the replication of the reactor and its operation are provided in detail. Three different composite systems (Pt/graphene, Pt/TiO2, and Au/TiO2) with monodisperse and uniformly distributed particles are produced by this reactor, and the photodeposition mechanism, as well as the synthesis optimization strategy, are discussed. The synthesis methods and their technical aspects are described comprehensively. The role of the ultraviolet (UV) dose (in each excitation pulse) on the photodeposition process is investigated and the optimum values for each composite system are provided.

For a continuous and scalable synthesis of noble-metal-based nanocomposites, a novel photocatalytic reactor is developed and its structure, operation principles, and product quality optimization strategies are described.

Un reattore di flusso continuo fotocatalitica di precisamente controllato deposizione di nanoparticelle metalliche

In this work, a novel photocatalytic reactor for the pulsed and controlled excitation of the photocatalyst and the precise deposition of metallic ...

Hydrogen Charging of Aluminum using Friction in Water

A new method of hydrogen charging of aluminum was developed by means of a friction in water (FW) procedure. This procedure can easily introduce high amounts of hydrogen into aluminum based on the chemical reaction between water and non-oxide coated aluminum.

In order to introduce high amounts of hydrogen in aluminum and aluminum alloys, a new method of hydrogen charging was developed, called the friction in water procedure.

Carica a idrogeno di alluminio con attrito in acqua

A new method of hydrogen charging of aluminum was developed by means of a friction in water (FW) procedure. This procedure can easily introduce high ...

Rapid Mix Preparation of Bioinspired Nanoscale Hydroxyapatite for Biomedical Applications

Hydroxyapatite (HA) has been widely used as a medical ceramic due to its good biocompatibility and osteoconductivity. Recently there has been interest regarding the use of bioinspired nanoscale hydroxyapatite (nHA). However, biological apatite is known to be calcium-deficient and carbonate-substituted with a nanoscale platelet-like morphology. Bioinspired nHA has the potential to stimulate optimal bone tissue regeneration due to its similarity to bone and tooth enamel mineral. Many of the methods currently used to fabricate nHA both in the laboratory and commercially, involve lengthy processes and complex equipment. Therefore, the aim of this study was to develop a rapid and reliable method to prepare high quality bioinspired nHA. The rapid mixing method developed was based upon an acid-base reaction involving calcium hydroxide and phosphoric acid. Briefly, a phosphoric acid solution was poured into a calcium hydroxide solution followed by stirring, washing and drying stages. Part of the batch was sintered at 1,000 &#176;C for 2 h in order to investigate the products&#39; high temperature stability. X-ray diffraction analysis showed the successful formation of HA, which showed thermal decomposition to &#946;-tricalcium phosphate after high temperature processing, which is typical for calcium-deficient HA. Fourier transform infrared spectroscopy showed the presence of carbonate groups in the precipitated product. The nHA particles had a low aspect ratio with approximate dimensions of 50 x 30 nm, close to the dimensions of biological apatite. The material was also calcium deficient with a Ca:P molar ratio of 1.63, which like biological apatite is lower than the stoichiometric HA ratio of 1.67. This new method is therefore a reliable and far more convenient process for the manufacture of bioinspired nHA, overcoming the need for lengthy titrations and complex equipment. The resulting bioinspired HA product is suitable for use in a wide variety of medical and consumer health applications.

This paper describes a novel method for the rapid manufacture of high quality bioinspired nanoscale hydroxyapatite. This biomaterial is of great significance in the manufacture of a wide range of innovative medical devices for clinical applications in orthopedics, craniofacial surgery and dentistry.

Rapid Mix Preparazione di bioispirati Nanoscale idrossiapatite per applicazioni biomediche

Hydroxyapatite (HA) has been widely used as a medical ceramic due to its good biocompatibility and osteoconductivity. Recently there has been interest ...

Bioingegneria

Sintesi e scoperta di MOF a base di fosfonati: un approccio solvotermico

Discovery and Synthesis Optimization of Isoreticular Al(III) Phosphonate-Based Metal-Organic Framework Compounds Using High-Throughput Methods

High-throughput (HT) methods are an important tool for the fast and efficient screening of synthesis parameters and the discovery of new materials. This manuscript describes the synthesis of metal-organic frameworks (MOFs) from solution using an HT reactor system, resulting in the discovery of various phosphonate-based MOFs of the composition [Al2H12-x(PMP)3]Clx&#8729;6H2O (H4PMP = N,N &#39;-piperazine bis(methylenephosphonic acid)) for x = 4, 6, denoted as Al-CAU-60-xHCl, containing trivalent aluminum ions. This was accomplished under solvothermal reaction conditions by systematically screening the impact of the molar ratio of the linker to the metal and the pH of the reaction mixture on the product formation. The protocol for the HT investigation includes six steps: a) synthesis planning (DOE = design of&#160;experiment) within the HT methodology, b) dosing and working with in-house developed HT reactors, c) solvothermal synthesis, d) synthesis workup using in-house developed filtration blocks, e) characterization by HT powder X-ray diffraction, and f) evaluation of the data. The HT methodology was first used to study the influence of acidity on the product formation, leading to the discovery of Al-CAU-60&#8729;xHCl (x = 4 or 6).

Autore in primo piano: Accelerare le scoperte nella chimica dei materiali microporosi 

The targeted synthesis of new metal-organic frameworks (MOFs) is difficult, and their discovery depends on the knowledge and creativity of the chemist. High-throughput methods allow complex synthetic parameter fields to be explored quickly and efficiently, accelerating the process of finding crystalline compounds and identifying synthetic and structural trends.

Scoperta e ottimizzazione della sintesi di composti isoreticolari a base di al(III) fosfonato metallo-organico mediante metodi ad alta produttività

High-throughput (HT) methods are an important tool for the fast and efficient screening of synthesis parameters and the discovery of new materials. This ...

Facile preparazione di particelle ultra-fine di idrossido di alluminio con o senza MCP-41 mesoporous in ambienti ambientali

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