Yazarlar, küçük açılı X-ışını kırınımı ve toz X-ışını kırınımı konusundaki analizleri ve uzmanlıkları için Rutgers Üniversitesi&#39;nden Dr. Thomas J. Emge ve Wei Liu&#39;ya teşekkürlerini sunar. Yazarlar ayrıca Hao Wang&#39;ı N 2 adsorpsiyon deneyleriyle desteklediği için onaylarlar.

1. Al (OH) 3 Nanopartikül Sentezi <ol><li> 1.40 g alüminyum klorid hekzahidrat 5.822 g deiyonize suda eritilir. </li><li> Manyetik olarak karıştırılarak sulu alüminyum klorür solüsyonuna 2.778 g L-arginin ilave edin. L-arginin yavaşça ilave edilir, böylece eklenen arginin erir ve büyük kümeler veya parçalar oluşturmaz; Ayrıca, yavaş bir ilave, yerel alkalilik konsantrasyonlarını azaltır ve daha kontrol edilebilir bir hidroliz için koşullar sağlar. </li><li> Tüm arginin çözeltiye karıştıktan sonra, çözeltiyi 50 ° C&#39;de 72 saat ısıtın; Bu noktada, çözüm bulutlu bir süspansiyon halinde görünebilir. </li></ol> 2. Al (OH) 3&#39;ün NaCI ile çökeltilmesi <ol><li> 49 uzunluğunda ve 1.125 çapında bir GPC sütunu hazırlayın. Jel ilavesinin ardışık basamaklarında jel koyun ve jel boncukları arasında en az boşluk bırakarak doğru ambalajlamayı sağlamak için suyun kolondan akmasına izin verin. Paketini verJel sütunun yaklaşık% 80&#39;i; Paketlenen jel miktarı her seferinde değişir ve yalnızca ayrılan türlerin alıkonma zamanını etkiler. </li><li> 10 mL&#39;lik enjektör döngüsü ile bir HPLC pompası kullanarak 10 mL sentezlenmiş Al (OH) 3 nanoparçacık süspansiyonu (adım 1.3&#39;te hazırlanan) kolona sokun. Enjektör döngüsünü, yaklaşık 0.125 inç çapında ve 10 mL enjekte edilen numuneyi vermek üzere kalibre edilen bir boru kullanılarak özel hale getirin. </li><li> DRI tepe konumu ile ilişkili aralıklarla sütun elution&#39;u toplayın. GPC çıktısını bir diferansiyel kırınım indeksi (dRI) dedektörünün girişine bağlayın. NOT: Ayrılan türler GPC&#39;den çıktıklarında, dri dedektöründe tepe noktası olarak görülür ve daha sonra 125 mL&#39;lik şişelerde toplanır. GPC sütunu, aljinik spektrumundan arginini ayırt etmek için, hem boyut tahliye kromatografisi (SEC) hem de elemental analiz (EA) ile toplanan ve analiz edilen iki iyi çözülmüş tepe noktası üretirleri. Toplanan toplam hacim, GPC sütununun boyutuna, kullanılan toplam paketleme maddesinin miktarına ve kolonun ayrılması için kullanılan deiyonize suyun debisine bağlı olacaktır. <ol><li> Pik 1 fraksiyonunun çoğunluğunu 0,2 mL / dakika akış oranında 100 dakika boyunca toplayın. </li><li> Eluent&#39;i, GPC sütununun RI detektöründe bir pik ortaya çıkınca 30 dakika aralıklarla toplayın. NOT: Aralık aralığının değiştirilmesi sonuçtaki saflaştırılmış zirve 1 maddesinin konsantrasyonunu ve saflığını değiştirir. Belirli bir kolon için en yüksek konsantrasyon ve pik 1 türünün hangi bölümünü içerdiğini belirlemek için zirveden küçük aralıklar toplamak daha iyidir. </li></ol></li><li> Ağırlıkça% 1 NaCl hazırlayın. </li><li> Hazırlanan NaCl solüsyonunu 10 mL saf Al (OH) 3 nanopartiküllerine damla damla ilave edin; NaCl çökeltme kullanılarak hazırlanan materyal daha deneyler için kullanılmaz. </li></ol> 3. Al-MCM-41&#39;in hazırlanması <ol><li> ACVakumlu bir fırında 3 saat süreyle 120 ° C&#39;de yaklaşık 1.0 g MCM-41&#39;yi aktif hale getirin. </li><li> 9.6926 g AlCl3.6H20 ile 40.3074 g deiyonize su birleştirilerek 50.0 g alüminyum klorür çözeltisi hazırlanır. </li><li> 0,7 g aktif MCM-41&#39;i, 50.0 g alüminyum klorür çözeltisine ilave edin (aşama 3.2&#39;de hazırlanmıştır). </li><li> MCM-41 kanalları boyunca yayılmış AlCl 3 homojenliğini sağlamak için yeterli karıştırma süresine (1 saat) izin verin. </li><li> Manyetik karıştırma altında 2.75&#39;lik bir Arg / Al molar oranına kadar heterojen karışıma L-arginin ilave edin. Adım 1.2&#39;ye benzer şekilde, arjinini, eklemeye devam etmeden önce, anında oluşan çöplerin tekrar çözülüp indirgenmesini ve arjininin kümeleşmesini azaltmasını sağlayacak kadar yavaş yavaş ilave edin. </li><li> Bir kez homojen hale getirildiğinde, karışım 50 ° C&#39;de 72 saat ısıtılır. </li><li> Elde edilen heterojen çözeltiyi vakum altında ve niteliksel 90 mm filtre kağıdı daireleriyle donatılmış bir Buchner hunisi kullanarak filtre edin(Veya uygun herhangi bir filtre kâğıdı). </li><li> Üretilen Al-MCM-41 materyalinden reaksiyona girmemiş alüminyum klorür, arginin veya suda çözünür yan ürünlerin uzaklaştırılmasını sağlamak için filtrelenmiş beyaz tozu fazla miktarda deiyonize su ile yıkayın. </li></ol>

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Rev. 106 (1), 1-16 (2006).</li><li>Lutzenkirchen, J., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Adsorption+of+Al13-Keggin+clusters+to+sapphire+c-plane+single+crystals:+Kinetic+observations+by+streaming+current+measurements.">Adsorption of Al13-Keggin clusters to sapphire c-plane single crystals: Kinetic observations by streaming current measurements.</a> Appl. Surf. Sci. 256 (17), 5406-5411 (2010).</li><li>Mokaya, R., Jones, W. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Efficient+post-synthesis+alumination+of+MCM-41+using+aluminum+chlorohydrate+containing+Al+polycations.">Efficient post-synthesis alumination of MCM-41 using aluminum chlorohydrate containing Al polycations.</a> J. Mater. Chem. 9 (2), 555-561 (1999).</li><li>Brunauer, S., Deming, L. S., Deming, W. E., Teller, E. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=On+a+Theory+of+the+van+der+Waals+adsorption+of+gases.">On a Theory of the van der Waals adsorption of gases.</a> J. Am. Chem. Soc. 62 (7), 1723-1732 (1940).</li><li>Kresge, C. T., Leonowicz, M. E., Roth, W. J., Vartuli, J. C., Beck, J. S. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Ordered+mesoporous+molecular+sieves+synthesized+by+a+liquid-crystal+template+mechanism.">Ordered mesoporous molecular sieves synthesized by a liquid-crystal template mechanism.</a> Nature. 359 (6397), 710-712 (1992).</li><li>Zeng, Q., Nekvasil, H., Grey, C. P. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Proton+Environments+in+Hydrous+Aluminosilicate+Glasses:+A+1H+MAS,+1H/27Al,+and+1H/23Na+TRAPDOR+NMR+Study.">Proton Environments in Hydrous Aluminosilicate Glasses: A 1H MAS, 1H/27Al, and 1H/23Na TRAPDOR NMR Study.</a> J. Phys. Chem. B. 103 (35), 7406-7415 (1999).</li><li>Kao, H. M., Grey, C. P. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Probing+the+Bronsted+and+Lewis+acidity+of+zeolite+HY:+A+1H/27Al+and+15N/27Al+TRAPDOOR+NMR+study+of+mono-methylamine+adsorbed+on+HY.">Probing the Bronsted and Lewis acidity of zeolite HY: A 1H/27Al and 15N/27Al TRAPDOOR NMR study of mono-methylamine adsorbed on HY.</a> J. Phys. Chem. 100 (12), 5105-5117 (1996).</li><li>DeCanio, E. C., Edwards, J. C., Bruno, J. W. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Solid-state+1H+MAS+NMR+characterization+of+&#947;-alumina+and+modified+&#947;-aluminas.">Solid-state 1H MAS NMR characterization of &#947;-alumina and modified &#947;-aluminas.</a> J. Catal. 148 (1), 76-83 (1994).</li><li>Shafran, K. L., Deschaume, O., Perry, C. C. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=The+static+anion+exchange+method+for+generation+of+high+purity+aluminium+polyoxocations+and+monodisperse+aluminum+hydroxide+nanoparticles.">The static anion exchange method for generation of high purity aluminium polyoxocations and monodisperse aluminum hydroxide nanoparticles.</a> J. Mater. Chem. 15 (33), 3415-3423 (2005).</li><li>Vogels, R. J. M. J., Kloprogge, J. T., Geus, J. W. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Homogeneous+forced+hydrolysis+of+aluminum+through+the+thermal+decomposition+of+urea.">Homogeneous forced hydrolysis of aluminum through the thermal decomposition of urea.</a> J. Colloid Interface Sci. 285 (1), 86-93 (2005).</li></ol>

Yazarların açıklayacak bir şeyi yok.

Sulu bir alüminyum klorür çözeltisinin hazırlanması, alüminyum kloridin kristal halinde bir hekzahidrat tuzunun kullanılmasını gerektirdi. Susuz form da kullanılabilmesine rağmen, önemli higroskopik özelliklerinden dolayı tercih edilmemektedir; bu da, alüminyum konsantrasyonunu kontrol etmek ve kontrol etmek zorlaşmaktadır. Alüminyum klorür çözeltisinin hazırlığın birkaç gün içinde kullanılması gerektiğini dikkate alarak dikkatli olun çünkü zamanla [Al (H20) 6 ] 3 +</su...

Alüminyum hidroksit malzemelerin kataliz, ilaç, su arıtma ve kozmetik dahil olmak üzere endüstriyel uygulamalar için umut vadeden adaylar vardır. 1 , 2 , 3 , 4 Yüksek sıcaklıklarda, alüminyum hidroksit (Al2O3) üretmek için parçalanma esnasında önemli miktarda ısı emer ve bu da alev geciktirici bir ajan haline gelir. Alüminyum hidroksitin bilinen dört polimorfu ( yani , gibbsite, bayerit, nordstrandit ve doyleit) hesaplama ve deney yöntemleriyle araştırılarak oluşum ve yapılarının anlaşılması 6 . Nano ölçekli parçacıkların hazırlanması, kuantum efektleri sergileme potansiyeli ve teorilerinkinden farklı özelliklere sahip olması nedeniyle özellikle ilgi çekicidirR toplu meslektaşları. 100 nm düzeyindeki boyutlara sahip nanogibsit parçacıkları çeşitli koşullar altında kolaylıkla hazırlanır 7 , 8 , 9 , 10 , 11 , 12 , 13 , 14 . Parçacık boyutlarını daha da azaltmakla ilgili olarak ortaya çıkan zorlukların üstesinden gelmek zordur; Bu nedenle, nanogibbsite parçacıkların boyutları 50 nm civarında olduğu yalnızca birkaç durum mevcuttur. 14 , 15 , 16 , 17 Bildiğimiz kadarıyla, 50 nm&#39;den daha küçük nanogibit partikülleri raporu bulunmamaktadır. Kısmen, nanoparçacıkların elektrostatik istikrarsızlıktan ötürü yığılma eğilimi gösterdiği düşünülmektedirVe özellikle polar protik çözücülerde koloidal partiküller arasında hidrojen bağlarının oluşma ihtimali yüksektir. Amacımız, yalnızca güvenli maddeleri ve öncülleri kullanarak küçük Al (OH) 3 nanopartiküllerini sentezlemekti. Mevcut çalışmada, bir tampon ve stabilizör olarak bir amino asit ( yani , L-arginin) eklenerek sulu parçacık agregasyonu engellendi. Dahası guanidinyum içeren argininin, alüminyum hidroksit parçacıklarının büyümesini ve toplanmasını önlediği ve ortalama parçacık boyutları 10-30 nm olan sulu bir koloidal süspansiyon oluşturduğu bildirilmektedir. Argininin amfoterik ve zvitteriyonik özelliklerinin, hafif hidroliz sırasında alüminyum hidroksit nanopartikülleri yüzey yükünü hafiflettiği ve 30 nm&#39;nin ötesinde partikül büyümesini hafiflettiği önerilir. Arginin, parçacık boyutunu 10 nm&#39;nin altına düşürememekle birlikte, bu parçacıklar, &quot;kafes&quot; sınırlandırıcı etkiden yararlanılarak elde edilmiştirMCM-41&#39;in mezo gözeneklerinde. Al-MCM-41 bileşik maddesinin karakterizasyonu, 2.7 nm&#39;lik bir ortalama gözenek boyutuna sahip olan mezo-gözenekli silisyum içinde ultra ince alüminyum hidroksit nanopartiküllerini ortaya çıkarmıştır.

<table border="0" cellpadding="0" cellspacing="0" width="650">
	<tbody>
		<tr height="21">
			<td height="21" style="height:21px;width:261px;">aluminum chloride hexahydrate</td>
			<td style="width:103px;">Alfa Aesar</td>
			<td align="right" style="width:119px;">12297</td>
			<td style="width:167px;"></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:261px;">L-arginine</td>
			<td style="width:103px;">BioKyowa</td>
			<td style="width:119px;">N/A</td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:261px;">aluminum hydroxide</td>
			<td style="width:103px;">Sigma Aldrich</td>
			<td align="right" style="width:119px;">239186</td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:261px;">Bio-Gel P-4 Gel</td>
			<td style="width:103px;">Bio-Rad</td>
			<td style="width:119px;">150-4128</td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:261px;">Mesoporous siica (MCM-41 type)</td>
			<td style="width:103px;">Sigma Aldrich</td>
			<td align="right" style="width:119px;">643645</td>
			<td></td>
		</tr>
	</tbody>
</table>

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

Nanogibbsite ait sulu bir süspansiyon, alüminyum su asidi [Al (H20) 6 ] 3+ &#39;nın L-arginin ile pH 4.6&#39;ya titrasyonu ile sentezlendi. Sulu alüminyum tuzlarının hidrolizinin, geniş bir boyut dağılımı dağılımına sahip geniş bir ürün yelpazesi ürettiği bilinmekle birlikte, çeşitli son teknoloji cihazlar ( yani, 27 Al / 1 H NMR, FTIR, ICP-OES , TEM-EDX, XPS, XRD ve BET), sentez ürünlerini ve yan ürünlerin tanımlanmasını karakterize etmek için kullanıldı. Nanopartiküllerden (10-30 nm) oluşan ürün, jel permeasyon kromatografisi (GPC) sütun tekniği kullanılarak izole edildi. Fourier transform infrared (FTIR) spektroskopisi ve toz X-ışını kırınımı (PXRD) saflaştırılmış materyali alüminyum hidroksitin gibbsite polimorfu olarak tanımladı. İnorganik tuzların ( örn. , NaCl) ilavesi, süspansiyonun elektrostatik istikrarsızlaştırılmasına yol açtı, böylece nanoparçacıkların yoğundurulması sağlandıAl Al (OH) 3 , büyük parçacık boyutlarıyla çökelir. Burada tarif edilen yeni sentetik metodu kullanarak Al (OH) 3 , MCM-41&#39;in yüksek derecede düzenlenmiş mezo-gözenekli çerçevesinin içinde ortalama gözenek boyutları 2.7 nm olan kısmen yüklendi ve hem oktahedral hem de tetrahedral Al (O / saat) ile bir alüminosilikat malzeme üretti. T d = 1.4). Enerji dağılımlı X-ışını spektrometresi (EDX) kullanılarak ölçülen toplam Al içeriği,% 2.9 Si / Al molar oranı ile% 11 idi. Toplu EDX&#39;in yüzey X-ışını fotoelektron spektroskopisi (XPS) element analizi ile karşılaştırılması, alüminosilikat materyal içindeki Al dağılımı hakkında bilgi sağlamıştır. Dahası, dış yüzeyde (3.6) hacim (2.9) ile karşılaştırıldığında Si / Al oranının daha yüksek olduğu görülmüştür. O / Al oranlarının yaklaşıklıkları sırasıyla çekirdeğin ve dış yüzeyin yakınında daha yüksek bir Al (O) 3 ve Al (O) 4 konsantrasyonuna işaret etmektedir. Al-MCM-41&#39;in yeni geliştirilmiş sentezi,Sıralı yüksek silisyum dioksit muhteviyatı sağlarken, sıralı silis çerçevesinin bütünlüğünü korur ve hidratlı veya susuz AI203 nanopartiküllerin avantajlı olduğu uygulamalar için kullanılabilir.

Nanogibsit Sentezi Nanogibsit, AlCl3 · 6H20 (ağırlıkça% 14) L-arginin ile son bir Arg / Al mol oranının 2.75&#39;e kadar titre edilmesiyle hazırlandı. Nanogibbsite parçacıkların sentezi, kısmen hidrolize edilmiş alüminyum klorür çözeltileri için yaygın olarak kullanılan bir analiz tekniği olan, zirveleri 1, 2, 3, 4 ve 5 1 olarak belirlenen beş alanı belirleyebilen SEC aracılığıy...

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

Çok ince bir alüminyum hidroksit nanoparçacık süspansiyonu, MCM-41&#39;in mezogözenekli kanalları içinde kafes efekti kısıtlaması olmaksızın ve olmadan 4.6&#39;ya kadar L-arginin ile [Al (H20)] 3&#39;ün kontrollü titrasyonu ile hazırlandı.

Ortofim Ortamlarda Mesafor MCM-41&#39;li olsun olmasın Ultrafine Alüminyum Hidroksit Parçacıklarının Kolay Hazırlanması

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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JoVE Journal

Chemistry

10.8K Görüntüleme.  Colgate-Palmolive Company.  Çok ince bir alüminyum hidroksit nanoparçacık süspansiyonu, MCM-41'in mezogözenekli kanalları içinde kafes efekti kısıtlaması olmaksızın ve olmadan 4.6'ya kadar L-arginin ile [Al (H20)] 3'ün kontrollü titrasyonu ile hazırlandı. 

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

Particles without a Box: Brush-first Synthesis of Photodegradable PEG Star Polymers under Ambient Conditions

Convenient methods for the rapid, parallel synthesis of diversely functionalized nanoparticles will enable discovery of novel formulations for drug delivery, biological imaging, and supported catalysis. In this report, we demonstrate parallel synthesis of brush-arm star polymer (BASP) nanoparticles by the &#34;brush-first&#34; method. In this method, a norbornene-terminated poly(ethylene glycol) (PEG) macromonomer (PEG-MM) is first polymerized via ring-opening metathesis polymerization (ROMP) to generate a living brush macroinitiator. Aliquots of this initiator stock solution are added to vials that contain varied amounts of a photodegradable bis-norbornene crosslinker. Exposure to crosslinker initiates a series of kinetically-controlled brush+brush and star+star coupling reactions that ultimately yields BASPs with cores comprised of the crosslinker and coronas comprised of PEG. The final BASP size depends on the amount of crosslinker added. We carry out the synthesis of three BASPs on the benchtop with no special precautions to remove air and moisture. The samples are characterized by gel permeation chromatography (GPC); results agreed closely with our previous report that utilized inert (glovebox) conditions. Key practical features, advantages, and potential disadvantages of the brush-first method are discussed.

Poly(ethylene glycol) (PEG) brush-arm star polymers (BASPs) with narrow mass distributions and tunable nanoscopic sizes are synthesized in via ring opening metathesis polymerization (ROMP) of a PEG-norbornene macromonomer followed by transfer of portions of the resulting living brush initiator to vials containing varied amounts of a rigid, photo-cleavable bis-norbornene crosslinker.

Koli olmadan Parçacıklar: Ortam Koşullarında fotoaynşmaya PEG Yıldız Polimerlerin Fırça-ilk Sentez

Convenient methods for the rapid, parallel synthesis of diversely functionalized nanoparticles will enable discovery of novel formulations for drug ...

Kimya

Activating Molecules, Ions, and Solid Particles with Acoustic Cavitation

The chemical and physical effects of ultrasound arise not from a direct interaction of molecules with sound waves, but rather from the acoustic cavitation: the nucleation, growth, and implosive collapse of microbubbles in liquids submitted to power ultrasound. The violent implosion of bubbles leads to the formation of chemically reactive species and to the emission of light, named sonoluminescence. In this manuscript, we describe the techniques allowing study of extreme intrabubble conditions and chemical reactivity of acoustic cavitation in solutions. The analysis of sonoluminescence spectra of water sparged with noble gases provides evidence for nonequilibrium plasma formation. The photons and the "hot" particles generated by cavitation bubbles enable to excite the non-volatile species in solutions increasing their chemical reactivity. For example the mechanism of ultrabright sonoluminescence of uranyl ions in acidic solutions varies with uranium concentration: sonophotoluminescence dominates in diluted solutions, and collisional excitation contributes at higher uranium concentration. Secondary sonochemical products may arise from chemically active species that are formed inside the bubble, but then diffuse into the liquid phase and react with solution precursors to form a variety of products. For instance, the sonochemical reduction of Pt(IV) in pure water provides an innovative synthetic route for monodispersed nanoparticles of metallic platinum without any templates or capping agents. Many studies reveal the advantages of ultrasound to activate the divided solids. In general, the mechanical effects of ultrasound strongly contribute in heterogeneous systems in addition to chemical effects. In particular, the sonolysis of PuO2 powder in pure water yields stable colloids of plutonium due to both effects.

Acoustic cavitation in liquids submitted to power ultrasound creates transient extreme conditions inside the collapsing bubbles, which are the origin of unusual chemical reactivity and light emission, known as sonoluminescence. In the presence of noble gases, nonequilibrium plasma is formed. The "hot" particles and the photons generated by collapsing bubbles are able to excite species in solution.

Moleküller, İyonlar, ve Akustik Kavitasyon ile Katı Parçacıklar etkinleştirilmesi

The chemical and physical effects of ultrasound arise not from a direct interaction of molecules with sound waves, but rather from the acoustic ...

Synthesis and Catalytic Performance of Gold Intercalated in the Walls of Mesoporous Silica

As a promising catalytically active nano reactor, gold nanoparticles intercalated in mesoporous silica (GMS) were successfully synthesized and properties of the materials were investigated. We used a one pot sol-gel approach to intercalate gold nano particles in the walls of mesoporous silica. To start with the synthesis, P123 was used as template to form micelles. Then TESPTS was used as a surface modification agent to intercalate gold nano particles. Following this process, TEOS was added in as a silica source which underwent a polymerization process in acid environment. After hydrothermal processing and calcination, the final product was acquired. Several techniques were utilized to characterize the porosity, morphology and structure of the gold intercalated mesoporous silica. The results showed a stable structure of mesoporous silica after gold intercalation. Through the oxidation of benzyl alcohol as a benchmark reaction, the GMS materials showed high selectivity and recyclability.

Here, we present a protocol with a sol-gel process to synthesize gold intercalated in the walls of mesoporous materials (GMS), which is confirmed to possess a mesoporous matrix with gold intercalated in the walls imparting great stability and recyclability.

Sentezi ve Mezogözenekli Silika Walls Altın interkalasyonlu Katalitik Performans

As a promising catalytically active nano reactor, gold nanoparticles intercalated in mesoporous silica (GMS) were successfully synthesized and properties ...

Facile and Efficient Preparation of Tri-component Fluorescent Glycopolymers via RAFT-controlled Polymerization

Synthetic glycopolymers are instrumental and versatile tools used in various biochemical and biomedical research fields. An example of a facile and efficient synthesis of well-controlled fluorescent statistical glycopolymers using reversible addition-fragmentation chain-transfer (RAFT)-based polymerization is demonstrated. The synthesis starts with the preparation of &#946;-galactose-containing glycomonomer 2-lactobionamidoethyl methacrylamide obtained by reaction of lactobionolactone and N-(2-aminoethyl) methacrylamide (AEMA). 2-Gluconamidoethyl methacrylamide (GAEMA) is used as a structural analog lacking a terminal &#946;-galactoside. The following RAFT-mediated copolymerization reaction involves three different monomers: N-(2-hydroxyethyl) acrylamide as spacer, AEMA as target for further fluorescence labeling, and the glycomonomers. Tolerant of aqueous systems, the RAFT agent used in the reaction is (4-cyanopentanoic acid)-4-dithiobenzoate. Low dispersities (&#8804;1.32), predictable copolymer compositions, and high reproducibility of the polymerizations were observed among the products. Fluorescent polymers are obtained by modifying the glycopolymers with carboxyfluorescein succinimidyl ester targeting the primary amine functional groups on AEMA. Lectin-binding specificities of the resulting glycopolymers are verified by testing with corresponding agarose beads coated with specific glycoepitope recognizing lectins. Because of the ease of the synthesis, the tight control of the product compositions and the good reproducibility of the reaction, this protocol can be translated towards preparation of other RAFT-based glycopolymers with specific structures and compositions, as desired.

An efficient, three-step synthesis of RAFT-based fluorescent glycopolymers, consisting of glycomonomer preparation, copolymerization, and post-modification, is demonstrated. This protocol can be used to prepare RAFT-based statistical glycopolymers with desired structures.

RAFT kontrollü Polimerizasyon yoluyla Tri-bileşenli Floresan Glycopolymers uyduruk ve Etkin Hazırlık

Synthetic glycopolymers are instrumental and versatile tools used in various biochemical and biomedical research fields. An example of a facile and ...

Construction and Systematical Symmetric Studies of a Series of Supramolecular Clusters with Binary or Ternary Ammonium Triphenylacetates

Functions of clusters in nano or sub-nano scale significantly depend on not only kinds of their components but also arrangements, or symmetry, of their components. Therefore, the arrangements in the clusters have been precisely characterized, especially for metal complexes. Contrary to this, characterizations of molecular arrangements in supramolecular clusters composed of organic molecules are limited to a few cases. This is because construction of the supramolecular clusters, especially obtaining a series of the supramolecular clusters, is difficult due to low stability of non-covalent bonds compare to covalent bonds. From this viewpoint, utilization of organic salts is one of the most useful strategies. A series of the supramolecules could be constructed by combinations of a specific organic molecule with various counter ions. Especially, primary ammonium carboxylates are suitable as typical examples of supramolecules because various kinds of carboxylic acids and primary amines are commercially available, and it is easy to change their combinations. Previously, it was demonstrated that primary ammonium triphenylacetates using various kinds of primary amines specifically construct supramolecular clusters, which are composed of four ammoniums and four triphenylacetates assembled by charge-assisted hydrogen bonds, in crystals obtained from non-polar solvents. This study demonstrates an application of the specific construction of the supramolecular clusters as a strategy to conduct systematical symmetric study for clarification of correlations between molecular arrangements in supramolecules and kinds and numbers of their components. In the same way with binary salts composed of triphenylacetates and one kind of primary ammoniums, ternary organic salts composed of triphenylacetates and two kinds of ammoniums construct the supramolecular clusters, affording a series of the supramolecular clusters with various kinds and numbers of the components.

This article describes construction of a series of hydrogen-bonding supramolecular clusters in crystals using primary ammonium triphenylacetates, which are recrystallized from non-polar solvents. This selective construction of the supramolecular clusters leads to effective systematical symmetric studies about a correlation between the supramolecular clusters and their components.

İnşaat ve İkili veya Üçlü Amonyum trifenilasetatlar ile Supramoleküler Kümeleri Bir Seri Sistematik Simetrik Çalışmaları

Functions of clusters in nano or sub-nano scale significantly depend on not only kinds of their components but also arrangements, or symmetry, of their ...

Facile Preparation of Internally Self-assembled Lipid Particles Stabilized by Carbon Nanotubes

We present a facile method to prepare nanostructured lipid particles stabilized by carbon nanotubes (CNTs). Single-walled (pristine) and multi-walled (functionalized) CNTs are used as stabilizers to produce Pickering type oil-in-water (O/W) emulsions. Lipids namely, Dimodan U and Phytantriol are used as emulsifiers, which in excess water self-assemble into the bicontinuous cubic Pn3m phase. This highly viscous phase is fragmented into smaller particles using a probe ultrasonicator in presence of conventional surfactant stabilizers or CNTs as done here. Initially, the CNTs (powder form) are dispersed in water followed by further ultrasonication with the molten lipid to form the final emulsion. During this process the CNTs get coated with lipid molecules, which in turn are presumed to surround the lipid droplets to form a particulate emulsion that is stable for months. The average size of CNT-stabilized nanostructured lipid particles is in the submicron range, which compares well with the particles stabilized using conventional surfactants. Small angle X-ray scattering data confirms the retention of the original Pn3m cubic phase in the CNT-stabilized lipid dispersions as compared to the pure lipid phase (bulk state). Blue shift and lowering of the intensities in characteristic G and G&#39; bands of CNTs observed in Raman spectroscopy characterize the interaction between CNT surface and lipid molecules. These results suggest that the interactions between the CNTs and lipids are responsible for their mutual stabilization in aqueous solutions. As the concentrations of CNTs employed for stabilization are very low and lipid molecules are able to functionalize the CNTs, the toxicity of CNTs is expected to be insignificant while their biocompatibility is greatly enhanced. Hence the present approach finds a great potential in various biomedical applications, for instance, for developing hybrid nanocarrier systems for the delivery of multiple functional molecules as in combination therapy or polytherapy.

We report on a smart application of carbon nanotubes for kinetic stabilization of lipid particles that contain self-assembled nanostructures in their cores. The preparation of lipid particles requires rather low concentrations of carbon nanotubes permitting their use in biomedical applications such as drug delivery.

Karbon Nanotüpler tarafından Stabilize İçeriden Kendinden monte Lipid Parçacıklar uyduruk hazırlanması

We present a facile method to prepare nanostructured lipid particles stabilized by carbon nanotubes (CNTs). Single-walled (pristine) and multi-walled ...

Facile Preparation of 4-Substituted Quinazoline Derivatives

Reported in this paper is a very simple method for direct preparation of 4-substituted quinazoline derivatives from a reaction between substituted 2-aminobenzophenones and thiourea in the presence of dimethyl sulfoxide (DMSO). This is a unique complementary reaction system in which thiourea undergoes thermal decomposition to form carbodiimide and hydrogen sulfide, where the former reacts with 2-aminobenzophenone to form 4-phenylquinazolin-2(1H)-imine intermediate, whilst hydrogen sulfide reacts with DMSO to give methanethiol or other sulfur-containing molecule which then functions as a complementary reducing agent to reduce 4-phenylquinazolin-2(1H)-imine intermediate into 4-phenyl-1,2-dihydroquinazolin-2-amine. Subsequently, the elimination of ammonia from 4-phenyl-1,2-dihydroquinazolin-2-amine affords substituted quinazoline derivative. This reaction usually gives quinazoline derivative as a single product arising from 2-aminobenzophenone as monitored by GC/MS analysis, along with small amount of sulfur-containing molecules such as dimethyl disulfide, dimethyl trisulfide, etc. The reaction usually completes in 4-6 hr at 160 &#186;C in small scale but may last over 24 hr when carried out in large scale. The reaction product can be easily purified by means of washing off DMSO with water followed by column chromatography or thin layer chromatography.

A protocol for facile preparation of 4-substituted quinazoline derivatives from 2-aminobenzophenones, thiourea and dimethyl sulfoxide is presented.

4-Değiştirildi Kinazolin Türev kolay hazırlanması

Reported in this paper is a very simple method for direct preparation of 4-substituted quinazoline derivatives from a reaction between substituted ...

Visualization of Ambient Mass Spectrometry with the Use of Schlieren Photography

This manuscript outlines how to visualize mass spectrometry ambient ionization sources using schlieren photography. In order to properly optimize the mass spectrometer, it is necessary to characterize and understand the physical principles of the source. Most commercial ambient ionization sources utilize jets of nitrogen, helium, or atmospheric air to facilitate the ionization of the analyte. As a consequence, schlieren photography can be used to visualize the gas streams by exploiting the differences in refractive index between the streams and ambient air for visualization in real time. The basic setup requires a camera, mirror, flashlight, and razor blade. When properly configured, a real time image of the source is observed by watching its reflection. This allows for insight into the mechanism of action in the source, and pathways to its optimization can be elucidated. Light is shed on an otherwise invisible situation.

This paper presents a protocol for the visualization of gaseous streams of an ambient ionization source using schlieren photography and mass spectrometry.

Schlieren Fotoğraf Kullanımına Ortam kütle spektrometresi görselleştirme

This manuscript outlines how to visualize mass spectrometry ambient ionization sources using schlieren photography. In order to properly optimize the mass ...

Facile Synthesis of Worm-like Micelles by Visible Light Mediated Dispersion Polymerization Using Photoredox Catalyst

Presented herein is a protocol for the facile synthesis of worm-like micelles by visible light mediated dispersion polymerization. This approach begins with the synthesis of a hydrophilic poly(oligo(ethylene glycol) methyl ether methacrylate) (POEGMA) homopolymer using reversible addition-fragmentation chain-transfer (RAFT) polymerization. Under mild visible light irradiation (&#955; = 460 nm, 0.7 mW/cm2), this macro-chain transfer agent (macro-CTA) in the presence of a ruthenium based photoredox catalyst, Ru(bpy)3Cl2 can be chain extended with a second monomer to form a well-defined block copolymer in a process known as Photoinduced Electron Transfer RAFT (PET-RAFT). When PET-RAFT is used to chain extend POEGMA with benzyl methacrylate (BzMA) in ethanol (EtOH), polymeric nanoparticles with different morphologies are formed in situ according to a polymerization-induced self-assembly (PISA) mechanism. Self-assembly into nanoparticles presenting POEGMA chains at the corona and poly(benzyl methacrylate) (PBzMA) chains in the core occurs in situ due to the growing insolubility of the PBzMA block in ethanol. Interestingly, the formation of highly pure worm-like micelles can be readily monitored by observing the onset of a highly viscous gel in situ due to nanoparticle entanglements occurring during the polymerization. This process thereby allows for a more reproducible synthesis of worm-like micelles simply by monitoring the solution viscosity during the course of the polymerization. In addition, the light stimulus can be intermittently applied in an ON/OFF manner demonstrating temporal control over the nanoparticle morphology.

This article describes a process for producing polymeric self-assembled nanoparticles using visible light mediated dispersion polymerization. Using low energy visible light to control the polymerization allows for the reproducible formation of self-assembled worm-like micelles at high solids content.

Photoredox Katalizörü kullanarak görünür ışık aracılığı ile dispersiyon polimerleştirilmesi ile solucan gibi miseller Facile sentezi

Presented herein is a protocol for the facile synthesis of worm-like micelles by visible light mediated dispersion polymerization. This approach begins ...

Facile Preparation of (2Z,4E)-Dienamides by the Olefination of Electron-deficient Alkenes with Allyl Acetate

Direct cross-coupling between two alkenes via vinylic C-H bond activation represents an efficient strategy for the synthesis of butadienes with high atomic and step economy. However, this functionality-directed cross-coupling reaction has not been developed, as there are still limited directing groups in practical use. In particular, a stoichiometric amount of oxidant is usually required, producing a large amount of waste. Due to our interest in novel 1,3-butadiene synthesis, we describe the ruthenium-catalyzed olefination of electron-deficient alkenes using allyl acetate and without external oxidant. The reaction of 2-phenyl acrylamide and allyl acetate was chosen as a model reaction, and the desired diene product was obtained in 80% isolated yield with good stereoselectivity (Z,E/Z,Z = 88:12) under optimal conditions: [Ru(p-cymene) Cl2]2 (3 mol %) and AgSbF6 (20 mol %) in DCE at 110 &#186;C for 16 h. With the optimized catalytic conditions in hand, representative &#945;- and/or &#946;-substituted acrylamides were investigated, and all reacted smoothly, regardless of aliphatic or aromatic groups. Also, differently N-substituted acrylamides have proven to be good substrates. Moreover, we examined the reactivity of different allyl derivatives, suggesting that the chelation of acetate oxygen to the metal is crucial for the catalytic process. Deuterium-labeled experiments were also conducted to investigate the reaction mechanism. Only Z-selective H/D exchanges on acrylamide were observed, indicating a reversible cyclometalation event. In addition, a kinetic isotope effect (KIE) of 3.2 was observed in the intermolecular isotopic study, suggesting that the olefinic C-H metalation step is probably involved in the rate-determining step.

Facile Preparation of 2Z,4E-Dienamides by the Olefination of Electron-deficient Alkenes with Allyl Acetate

The ruthenium-catalyzed olefination of electron-deficient alkenes with allyl acetate is described here. By using aminocarbonyl as a directing group, this external oxidant-free protocol has high efficiency and good stereo- and regioselectivity, opening a novel synthetic route to (Z,E)-butadiene skeletons.

Kolay Hazırlık (2<em&gt; Z</em&gt; 4<em&gt; E</em&gt;) - Alil Asetat ile Elektronuz Alkenlerin Olefinasyonu ile Dienamidler

Direct cross-coupling between two alkenes via vinylic C-H bond activation represents an efficient strategy for the synthesis of butadienes with high ...