This work is partially supported by NSF (DMR-1006870) and NASA (NASA-NNX13AQ60G). X. Z. Wang acknowledges support from the Mary Kay O'Connor Process Safety Center (MKOPSC) at Texas A&amp;M University. We also thank Min Shuai for her guidance.

Hidrotermal Yöntemle α-ZrP 1. Sentezi <ol><li> Zirkonil klorür oktahidrat 6 g (ZrOCl 2 · 8H 2 O), 3.75 mi, 150 ml (Dİ) su deiyonize edilmiş yuvarlak dipli bir reaksiyon kabına çözülür. </li><li> Kuvvetli karıştırma altında (Dİ) su deiyonize 8.25 ml ilave edilmiş, adım 1.1 hazırlanan ZrOCl 2 çözeltisine 15 M fosforik asit (3 konumundaki H atomu PO 4) damla damla 48 ml ilave edilir. </li><li> 80 mi hacim Teflon astarlı basınç kabına jel benzeri bir karışım elde dökün. paslanmaz çelik kabuk ve kapak, baskı plakası oluşan hidrotermal otoklav içine bir kap yerleştirin ve sonra iyi sıkın. </li><li> 24 saat boyunca 200 ° C&#39;de konveksiyon fırınında içine hidrotermal otoklav yerleştirin. </li><li> Tepkimeden sonra, hidrotermal otoklav oda soğutma altında, oda sıcaklığında 8 saat soğumaya bırakın. </li><li> 2 de santrifüj kullanılarak soğuduktan sonra santrifüj tüpüne α-ZrP diskleri toplamak,10 dakika boyunca 500 x g. Üste kalan sıvının aşındırıcı olan girmemiş fosforik asit içerdiğinden atık bertaraf konteynerine sıvı kısmı toplayın. <ol><li> Daha sonra, yine 10 dakika süre ile 2500 x g de 1 dakika santrifüj hazır ZrP a kadar, 40 ml su, girdap ekleyin. asit Tüm yıkanıp olduğundan emin olmak için bu adım 3 kez tekrarlayın. </li></ol></li><li> daha sonra, 65 ° 8 saat C en fırınında ZrP su yapışkan karışımı havan tokmağı ve havan kullanarak öğütülür. </li></ol> Reflü Yöntemi ile α-ZrP 2. Sentezi <ol><li> 150 ml 12 M fosfat asit 50 ml yuvarlak tabanlı bir şişe · 8H 2 O ZrOCl 2 6 g karıştırın. </li><li> Aşama 2.1&#39;de elde edilen karışım 24 saat boyunca 94 ° C&#39;de yağ banyosu içinde geri akışa alınmıştır. </li><li> Aşama 1.6 DI su ile, aynı protokol çerçevesinde üç kez ürün yıkayın ve daha sonra 8 saat süre ile, 65 ° C&#39;de bir fırında kurutulmuştur. </li><li> Bir havan ve tokmağı ve stok f kullanarak toz haline kurutulmuş hacimli örnek eziyetveya daha sonra kullanın. </li></ol> Mikrodalga destekli Yöntemi ile α-ZrP 3. Sentezi <ol><li> 12 M fosforik asit çözeltisi 9 ml ZrOCl 2 · 8H 2 O 1 g ekleyin ve bir 20 mL sintilasyon şişesine iyi elde edilen karışım karıştırılır. </li><li> Mikrodalga reaktör için belirlenen 10 ml&#39;lik bir cam kaba, yukarıdaki karışım 5 ml dökün. </li><li> 150 ° C, 300 psi basınç sınırında yer alan reaksiyon sıcaklığı ve reaksiyon, 1 saat boyunca olmasına izin verin. </li><li> reaksiyondan sonra, cam kap yaklaşık 15 dakika soğumasını ve ardından asit yıkama ve α-ZrP kristallerin kurutulması için Adımlar 1,6-1,7 gibi aynı prosedürü takip edelim. </li></ol> Mono tabakaları halinde Tabakalı α-ZrP 4. soyulmasi <ol><li> Bir 20 mL sintilasyon şişesine DI 10 ml su içine α-ZrP 1 g dağıtılır. </li><li> en az 40 saniye için ve vorteks TBAOH (% 40 wt.) 2.2 ml ilave edilir. TBAOH 1 olarak tutulur: Zr o molar oranı dikkat edin 1. </li><li> 1-2 saat için elde edilen konsantre edildi süspansiyon sonikasyon ve TBA + iyonlarının ve kristallerin tam pul pul dökülme tam birleşmesini sağlamak için 3 gün boyunca bırakın. İsteğe bağlı olarak, konsantre edilir Süspansiyon daha pul pul dökülme elde edilmesi için, su ile (2 ila 3 kat seyreltilmiş) inceltilebilir. </li><li> alt kısmında yerleşmiş, kısmen dağılmış kristalleri kaldırmak için 1 saat boyunca yüksek dönme hızı (2500 xg) exfoliated örnekleri santrifüj. Başka bir kapta (ZrP Pullu) üst kısmını toplamak ve hiçbir tortu bulunana kadar işlemi tekrarlayın. </li></ol>

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There is nothing to disclose.

reflü yöntemi, muntazam çap ve kalınlıkta α-ZrP daha küçük bir boyut yapmak için iyi bir seçenektir. hidrotermal yönteme benzer şekilde, geri akış yöntemi hazırlanması zaman ile sınırlıdır. Genel olarak, bu kristallerinin oluşması için gerekli uzun bir zaman alır. geri akış yöntemi için gerekli olan uzun bir reaksiyon süresi daha büyük bir boyuta sahip nanodisks neden olabilir. dağılmış nanodisks ortalama boyutu, dinamik ışık saçılımı (DLS) ile öl...

Diskotik kolloidler kil, asfalten, kırmızı kan hücreleri ve sedef şeklinde doğal olarak bol miktarda bulunmaktadır. Polimer nanokompozitler 1, biomimetic malzemeler, fonksiyonel membranların 2, diskotik sıvı kristal çalışmaları 3 ve 4 diskotik kolloidal nanodisks dayalı geliştirilirken Pickering emülsiyon stabilizatörleri dahil olmak üzere birçok mühendislik sistemlerinde uygulamalar, bir dizi. muntazamlığı ve düşük poli sahip Nanodisks fazlar ve sıvı kristaller dönüşümleri çalışmaları için önemlidir. Zirkonyum fosfat (ZrP) iyi sıralı katmanlı yapısı ve kontrol boy oranı (çapı üzerinde kalınlığı) ile sentetik nanodisks olduğunu. Bu nedenle, ZrP farklı sentezinin keşif diskotik sıvı kristal sisteminin temel anlayış oluşturulmasına yardımcı olmaktadır. ZrP yapısı 1964 5 Clearfield ve Stynes ​​ile açıklığa kavuşturulmuştur. ZrP, hidrotermal katmanlı kristallerinin sentezi için vereflü yöntemler yaygın 6,7 kabul edilir. Geri akış yöntemi aynı süresi zaman küçük kristaller verirken Hidrotermal yöntem olup, 400 ile% 25 6 içinde 1.500 nm ve poli kadar boyutuna iyi bir kontrol sağlar. Mikrodalga ısıtma nano 8 sentezi için umut verici bir yöntem olduğu kanıtlanmıştır. Ancak, mikrodalga destekli güzergah üzerinde ZrP sentezini açıklayan hiçbir kağıtları vardır. Boyut, en boy oranı ve hidrotermal yöntemi ile kristal büyüme mekanizması üzerinde etkili bir kontrol sistemli grubumuza 6 ile incelenmiştir. ZrP kolay sulu süspansiyonlar içinde mono-tabaka olarak dağılmış olabilir ve pul pul dökülmüş ZrP Cheng&#39;e grubunda 3,9-13 sıvı kristal malzeme olarak kurulmuştur. Şimdiye kadar, çeşitli çaplarda exfoliated ZrP nanodisks, farklı boy oranları büyük ZrP alt con de I (izotropik) -N (nematik) geçiş vardı sonucuna çalışılmıştır demekDaha küçük ZrP 3 ile karşılaştırıldığında sentrasyonu. Nematik sıvı kristal fazın oluşumu polidispersite 3, tuz 9 ve sıcaklık 10,11 etkileri de dikkate alınmıştır. Ayrıca, bu tür sematic sıvı kristal faz olarak başka fazlar yanı 13,14 incelenmiştir. Bu makalede, biz böyle bir kolloidal ZrP nanodisks süspansiyon deneysel gerçekleşmesini göstermektedir. Katmanlı ZrP kristaller farklı yöntemler kullanılarak sentezlenir ve daha sonra tek tabakalı nanodisks elde etmek üzere, sulu ortam içinde dağılmış olan. Sonunda, bu sistem tarafından sergilenen sıvı kristal faz geçişleri göstermektedir. Bu diskler bir önemli yönü, çapı oranının kalınlığı diskleri 3 boyutuna bağlı olarak 0.05 0.0007 aralığındadır onların yüksek ölçüde anizotropik doğasıdır. yüksek ölçüde anizotropik tek tabaka nanodisks nanodisks süspansiyonları faz geçişleri çalışmak için bir model sistem kurmak.

<table border="0" cellpadding="0" cellspacing="0" height="202" width="928">
	<tbody>
		<tr height="21">
			<td height="21" style="height:21px;width:209px;">Material</td>
			<td style="width:208px;"></td>
			<td style="width:164px;"></td>
			<td style="width:352px;"></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;">Zirconyl Chloride Octahydrate</td>
			<td>Fischer Scientific (Acros Organics)</td>
			<td>AC20837-5000</td>
			<td>98% +&#160;</td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;">o-Phosphoric Acid</td>
			<td>Fischer Scientific</td>
			<td>A242-1</td>
			<td>&#62;= 85 %</td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;">Tetra Butyl Ammonium Hydroxide</td>
			<td>Acros Organics (Acros Organics)</td>
			<td>AC176610025</td>
			<td>40% wt. (1.5M)</td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;">Name</td>
			<td>Company</td>
			<td>Catalog Number</td>
			<td>Comments</td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;">Equipment</td>
			<td></td>
			<td></td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;">Reaction Oven</td>
			<td>Fischer Scientific</td>
			<td>CL2 centrifuge</td>
			<td>Isotemperature Oven (Temperature Upto 350&#160;C)</td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;">Centrifuge&#160;</td>
			<td>Thermo Scientific</td>
			<td>Not Available&#160;</td>
			<td>Rotation Speed : 100 - 4000 rpm</td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;">Microwave Reactor</td>
			<td>CEM Corporation</td>
			<td>Discover and Explorer SP</td>
			<td>Temp. Upto 300oC, Power upto 300W, Pressure upto 30bar</td>
		</tr>
	</tbody>
</table>

synthesis and exfoliation of discotic zirconium phosphates to obtain colloidal liquid crystals

Due to their abundance in natural clay and potential applications in advanced materials, discotic nanoparticles are of interest to scientists and engineers. Growth of such anisotropic nanocrystals through a simple chemical method is a challenging task. In this study, we fabricate discotic nanodisks of zirconium phosphate [Zr(HPO4)2&#183;H2O] as a model material using hydrothermal, reflux and microwave-assisted methods. Growth of crystals is controlled by duration time, temperature, and concentration of reacting species. The novelty of the adopted methods is that discotic crystals of size ranging from hundred nanometers to few micrometers can be obtained while keeping the polydispersity well within control. The layered discotic crystals are converted to monolayers by exfoliation with tetra-(n)-butyl ammonium hydroxide [(C4H9)4NOH, TBAOH]. Exfoliated disks show isotropic and nematic liquid crystal phases. Size and polydispersity of disk suspensions is highly important in deciding their phase behavior.

Şekil 1a-c gösterisi sırasıyla hidrotermal, reflü, ve mikrodalga destekli yöntemler, elde edilen α-ZrP nanodisks SEM görüntüleri. Bu α-ZrP nanodisks şekil ve sentez koşulları ve hazırlanan yöntemlerine bağlı olarak, farklı kalınlıkta altı köşeli olduğu gözlendi. Grubumuzun 6 A önceden bildirilen çalışma kristal büyüme zaman 48 saat ya da yukarıda, disklerin kenar keskin hale önerir. Genellikle, geri akış yöntemi verimleri b...

Watch this Scientific Journal Video about Synthesis and Exfoliation of Discotic Zirconium Phosphates to Obtain Colloidal Liquid Crystals at JoVE.com

Synthesis and Exfoliation of Discotic Zirconium Phosphates to Obtain Colloidal Liquid Crystals

A two dimensional model material of discotic zirconium phosphate was developed. The inorganic crystal with lamellar structure was synthesized by hydrothermal, reflux, and microwave-assisted methods. On exfoliation with organic molecules, layered crystals can be converted to monolayers, and nematic liquid crystal phase was formed at sufficient concentration of monolayers.

Sentezi ve diskotik Zirkonyum Fosfatların Eksfoliasyon Kolloidal Sıvı Kristaller Edinme

Due to their abundance in natural clay and potential applications in advanced materials, discotic nanoparticles are of interest to scientists and ...

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Chemistry

8.4K Görüntüleme.  Texas A&M University. A two dimensional model material of discotic zirconium phosphate was developed. The inorganic crystal with lamellar structure was synthesized by hydrothermal, reflux, and microwave-assisted methods. On exfoliation with organic molecules, layered crystals can be converted to monolayers, and nematic liquid crystal phase was formed at sufficient concentration of monolayers. 

Video: Synthesis and Exfoliation of Discotic Zirconium Phosphates to Obtain Colloidal Liquid Crystals

Nucleoside Triphosphates - From Synthesis to Biochemical Characterization

The traditional strategy for the introduction of chemical functionalities is the use of solid-phase synthesis by appending suitably modified phosphoramidite precursors to the nascent chain. However, the conditions used during the synthesis and the restriction to rather short sequences hamper the applicability of this methodology. On the other hand, modified nucleoside triphosphates are activated building blocks that have been employed for the mild introduction of numerous functional groups into nucleic acids, a strategy that paves the way for the use of modified nucleic acids in a wide-ranging palette of practical applications such as functional tagging and generation of ribozymes and DNAzymes. One of the major challenges resides in the intricacy of the methodology leading to the isolation and characterization of these nucleoside analogues.
	
	In this video article, we present a detailed protocol for the synthesis of these modified analogues using phosphorous(III)-based reagents. In addition, the procedure for their biochemical characterization is divulged, with a special emphasis on primer extension reactions and TdT tailing polymerization. This detailed protocol will be of use for the crafting of modified dNTPs and their further use in chemical biology.

The protocol described herein aims to explain and abridge the numerous obstacles in the way of the intricate route leading to modified nucleoside triphosphates. Consequently, this protocol facilitates both the synthesis of these activated building-blocks and their availability for practical applications.

Nükleosid trifosfatlar - sentezinden Biyokimyasal Karakterizasyonu için

The  traditional strategy for the introduction of chemical functionalities is the  use of solid-phase synthesis by appending suitably modified ...

Kimya

Exfoliation of Egyptian Blue and Han Blue, Two Alkali Earth Copper Silicate-based Pigments

In a visualized example of the ancient past connecting with modern times, we describe the preparation and exfoliation of CaCuSi4O10 and BaCuSi4O10, the colored components of the historic Egyptian blue and Han blue pigments. The bulk forms of these materials are synthesized by both melt flux and solid-state routes, which provide some control over the crystallite size of the product. The melt flux process is time intensive, but it produces relatively large crystals at lower reaction temperatures. In comparison, the solid-state method is quicker yet requires higher reaction temperatures and yields smaller crystallites. Upon stirring in hot water, CaCuSi4O10 spontaneously exfoliates into monolayer nanosheets, which are characterized by TEM and PXRD. BaCuSi4O10 on the other hand requires ultrasonication in organic solvents to achieve exfoliation. Near infrared imaging illustrates that both the bulk and nanosheet forms of CaCuSi4O10 and BaCuSi4O10 are strong near infrared emitters. Aqueous CaCuSi4O10 and BaCuSi4O10 nanosheet dispersions are useful because they provide a new way to handle, characterize, and process these materials in colloidal form.

The preparation and exfoliation of CaCuSi4O10&#160;and BaCuSi4O10 are described. Upon stirring in hot water, CaCuSi4O10 spontaneously exfoliates into monolayers, whereas BaCuSi4O10&#160;requires ultrasonication in organic solvents. Near infrared (NIR) imaging illustrates the NIR emission properties of these materials, and aqueous dispersions of these nanomaterials are useful for solution processing.

Mısır Mavi ve Han Blue, İki Alkali Toprak Bakır silikat esaslı Pigmentlerinin pul pul dökülme

In a visualized example of the ancient past connecting with modern times, we describe the preparation and exfoliation of CaCuSi4O10 and BaCuSi4O10, the ...

Quantitative and Qualitative Examination of Particle-particle Interactions Using Colloidal Probe Nanoscopy

Colloidal Probe Nanoscopy (CPN), the study of the nano-scale interactive forces between a specifically prepared colloidal probe and any chosen substrate using the Atomic Force Microscope (AFM), can provide key insights into physical interactions present within colloidal systems. Colloidal systems are widely existent in several applications including, pharmaceuticals, foods, paints, paper, soil and minerals, detergents, printing and much more.1-3 Furthermore, colloids can exist in many states such as emulsions, foams and suspensions. Using colloidal probe nanoscopy one can obtain key information on the adhesive properties, binding energies and even gain insight into the physical stability and coagulation kinetics of the colloids present within. Additionally, colloidal probe nanoscopy can be used with biological cells to aid in drug discovery and formulation development. In this paper we describe a method for conducting colloidal probe nanoscopy, discuss key factors that are important to consider during the measurement, and show that both quantitative and qualitative data that can be obtained from such measurements.

Colloidal probe nanoscopy can be used within a variety of fields to gain insight into the physical stability and coagulation kinetics of colloidal systems and aid in drug discovery and formulation sciences using biological systems. The method described within provides a quantitative and qualitative means to study such systems.

Kolloidal Probe Nanoscopy kullanarak parçacık-parçacık Etkileşimleri Nicel ve Nitel Sınav

Colloidal Probe Nanoscopy (CPN), the study of the nano-scale interactive forces between a specifically prepared colloidal probe and any chosen substrate ...

From Constructs to Crystals &#8211; Towards Structure Determination of &#946;-barrel Outer Membrane Proteins

Membrane proteins serve important functions in cells such as nutrient transport, motility, signaling, survival and virulence, yet constitute only ~1% percent of known structures. There are two types of membrane proteins, &#945;-helical and &#946;-barrel. While &#945;-helical membrane proteins can be found in nearly all cellular membranes, &#946;-barrel membrane proteins can only be found in the outer membranes of mitochondria, chloroplasts, and Gram-negative bacteria. One common bottleneck in structural studies of membrane proteins in general is getting enough pure sample for analysis. In hopes of assisting those interested in solving the structure of their favorite &#946;-barrel outer membrane protein (OMP), general protocols are presented for the production of target &#946;-barrel OMPs at levels useful for structure determination by either X-ray crystallography and/or NMR spectroscopy. Here, we outline construct design for both native expression and for expression into inclusion bodies, purification using an affinity tag, and crystallization using detergent screening, bicelle, and lipidic cubic phase techniques. These protocols have been tested and found to work for most OMPs from Gram-negative bacteria; however, there are some targets, particularly for mitochondria and chloroplasts that may require other methods for expression and purification. As such, the methods here should be applicable for most projects that involve OMPs from Gram-negative bacteria, yet the expression levels and amount of purified sample will vary depending on the target OMP.

&#946;-barrel outer membrane proteins (OMPs) serve many functions within the outer membranes of Gram-negative bacteria, mitochondria, and chloroplasts. Here, we hope to alleviate a known bottleneck in structural studies by presenting protocols for the production of &#946;-barrel OMPs in sufficient quantities for structure determination by X-ray crystallography or NMR spectroscopy.

β-varil Dış Membran Proteinleri Yapı Tayini Doğru - Yapıların itibaren Crystals

Membrane proteins serve important functions in cells such as nutrient transport, motility, signaling, survival and virulence, yet constitute only ~1% ...

Synthesis of Programmable Main-chain Liquid-crystalline Elastomers Using a Two-stage Thiol-acrylate Reaction

This study presents a novel two-stage thiol-acrylate Michael addition-photopolymerization (TAMAP) reaction to prepare main-chain liquid-crystalline elastomers (LCEs) with facile control over network structure and programming of an aligned monodomain. Tailored LCE networks were synthesized using routine mixing of commercially available starting materials and pouring monomer solutions into molds to cure. An initial polydomain LCE network is formed via a self-limiting thiol-acrylate Michael-addition reaction. Strain-to-failure and glass transition behavior were investigated as a function of crosslinking monomer, pentaerythritol tetrakis(3-mercaptopropionate) (PETMP). An example non-stoichiometric system of 15 mol% PETMP thiol groups and an excess of 15 mol% acrylate groups was used to demonstrate the robust nature of the material. The LCE formed an aligned and transparent monodomain when stretched, with a maximum failure strain over 600%. Stretched LCE samples were able to demonstrate both stress-driven thermal actuation when held under a constant bias stress or the shape-memory effect when stretched and unloaded. A permanently programmed monodomain was achieved via a second-stage photopolymerization reaction of the excess acrylate groups when the sample was in the stretched state. LCE samples were photo-cured and programmed at 100%, 200%, 300%, and 400% strain, with all samples demonstrating over 90% shape fixity when unloaded. The magnitude of total stress-free actuation increased from 35% to 115% with increased programming strain. Overall, the two-stage TAMAP methodology is presented as a powerful tool to prepare main-chain LCE systems and explore structure-property-performance relationships in these fascinating stimuli-sensitive materials.

A novel methodology is presented to synthesize and program main-chain liquid-crystalline elastomers using commercially available starting monomers. A wide range of thermomechanical properties was tailored by adjusting the amount of crosslinker, while the actuation performance was dependent on the amount of applied strain during programming.

Bir iki-aşamalı Tiol akrilat reaksiyonu kullanılarak programlanabilir ana zincirli Sıvı kristal Elastomerler sentezi

This study presents a novel two-stage thiol-acrylate Michael addition-photopolymerization (TAMAP) reaction to prepare main-chain liquid-crystalline ...

Synthesis and Characterization of Supramolecular Colloids

Control over colloidal assembly is of utmost importance for the development of functional colloidal materials with tailored structural and mechanical properties for applications in photonics, drug delivery and coating technology. Here we present a new family of colloidal building blocks, coined supramolecular colloids, whose self-assembly is controlled through surface-functionalization with a benzene-1,3,5-tricarboxamide (BTA) derived supramolecular moiety. Such BTAs interact via directional, strong, yet reversible hydrogen-bonds with other identical BTAs. Herein, a protocol is presented that describes how to couple these BTAs to colloids and how to quantify the number of coupling sites, which determines the multivalency of the supramolecular colloids. Light scattering measurements show that the refractive index of the colloids is almost matched with that of the solvent, which strongly reduces the van der Waals forces between the colloids. Before photo-activation, the colloids remain well dispersed, as the BTAs are equipped with a photo-labile group that blocks the formation of hydrogen-bonds. Controlled deprotection with UV-light activates the short-range hydrogen-bonds between the BTAs, which triggers the colloidal self-assembly. The evolution from the dispersed state to the clustered state is monitored by confocal microscopy. These results are further quantified by image analysis with simple routines using ImageJ and Matlab. This merger of supramolecular chemistry and colloidal science offers a direct route towards light- and thermo-responsive colloidal assembly encoded in the surface-grafted monolayer.

A protocol for the synthesis and characterization of colloids coated with supramolecular moieties is described. These supramolecular colloids undergo self-assembly upon the activation of the hydrogen-bonds between the surface-anchored molecules by UV-light.

Supramoleküler Kolloidlerin Sentezi ve Karakterizasyonu

Control over colloidal assembly is of utmost importance for the development of functional colloidal materials with tailored structural and mechanical ...

From Molecules to Materials: Engineering New Ionic Liquid Crystals Through Halogen Bonding

Herein, we demonstrate that a bottom-up approach, based on halogen bonding (XB), can be successfully applied for the design of a new type of ionic liquid crystals (ILCs). Taking advantages of the high specificity of XB for haloperfluorocarbons and the ability of anions to act as XB-acceptors, we obtained supramolecular complexes based on 1-alkyl-3-methylimidazolium iodides and iodoperfluorocarbons, overcoming the well-known immiscibility between hydrocarbons (HCs) and perfluorocarbons (PFCs). The high directionality of the XB combined with the fluorophobic effect, allowed us to obtain enantiotropic liquid crystals where a rigid, non-aromatic, XB supramolecular anion acts as mesogenic core.
X-ray structure analysis of the complex between 1-ethyl-3-methylimidazolium iodide and iodoperfluorooctane showed the presence of a layered structure, which is a manifestation of the well-known tendency to segregation of perfluoroalkyl chains. This is consistent with the observation of smectic mesophases. Moreover, all the reported complexes melt below 100 &#176;C, and most are mesomorphic even at room temperature, despite that the starting materials were non-mesomorphic in nature.
The supramolecular strategy reported here provides new design principles for mesogen design allowing a totally new class of functional materials.

A protocol for the synthesis of a new type of mesogens, based on the halogen-bonded supramolecular anion [CnF2n+1-I&#183;&#183;&#183;I&#183;&#183;&#183;I-CnF2n+1]&#8722;, is reported.

Malzemeler molekülleri üzerinden: yeni iyonik sıvı kristaller halojen yoluyla mühendislik

Herein, we demonstrate that a bottom-up approach, based on halogen bonding (XB), can be successfully applied for the design of a new type of ionic liquid ...

Facet-to-facet Linking of Shape-anisotropic Colloidal Cadmium Chalcogenide Nanostructures

Here, we describe a protocol that allows for shape-anisotropic cadmium chalcogenide nanocrystals (NCs), such as nanorods (NRs) and tetrapods (TPs), to be covalently and site-specifically linked via their end facets, resulting in polymer-like linear or branched chains. The linking procedure begins with a cation-exchange process in which the end facets of the cadmium chalcogenide NCs are first converted to silver chalcogenide. This is followed by the selective removal of ligands at their surface. This results in cadmium chalcogenide NCs with highly reactive silver chalcogenide end facets that spontaneously fuse upon contact with each other, thereby establishing an interparticle facet-to-facet attachment. Through the judicious choice of precursor concentrations, an extensive network of linked NCs can be produced. Structural characterization of the linked NCs is carried out via low- and high-resolution transmission electron microscopy (TEM), as well as energy-dispersive X-ray spectroscopy, which confirm the presence of silver chalcogenide domains between chains of cadmium chalcogenide NCs.

A protocol detailing how shape-anisotropic colloidal cadmium chalcogenide nanocrystals can be covalently linked via their end facets is presented here.

Model model şekil-Yönbağımlı kolloidal kadmiyum Chalcogenide taşınımı bağlama

Here, we describe a protocol that allows for shape-anisotropic cadmium chalcogenide nanocrystals (NCs), such as nanorods (NRs) and tetrapods (TPs), to be ...

Novel Techniques for Observing Structural Dynamics of Photoresponsive Liquid Crystals

We discuss in this article the experimental measurements of the molecules in liquid crystal (LC) phase using the time-resolved infrared (IR) vibrational spectroscopy and time-resolved electron diffraction. Liquid crystal phase is an important state of matter that exists between the solid and liquid phases and it is common in natural systems as well as in organic electronics. Liquid crystals are orientationally ordered but loosely packed, and therefore, the internal conformations and alignments of the molecular components of LCs can be modified by external stimuli. Although advanced time-resolved diffraction techniques have revealed picosecond-scale molecular dynamics of single crystals and polycrystals, direct observations of packing structures and ultrafast dynamics of soft materials have been hampered by blurry diffraction patterns. Here, we report time-resolved IR vibrational spectroscopy and electron diffractometry to acquire ultrafast snapshots of a columnar LC material bearing a photoactive core moiety. Differential-detection analyses of the combination of time-resolved IR vibrational spectroscopy and electron diffraction are powerful tools for characterizing structures and photoinduced dynamics of soft materials.

Here, we present the protocols of differential-detection analyses of time-resolved infrared vibrational spectroscopy and electron diffraction which enable observations of the deformations of local structures around photoexcited molecules in a columnar liquid crystal, giving an atomic perspective on the relationship between the structure and the dynamics of this photoactive material.

Yapısal Photoresponsive sıvı kristaller dinamikleri gözlemlemek için yeni teknikleri

We discuss in this article the experimental measurements of the molecules in liquid crystal (LC) phase using the time-resolved infrared (IR) vibrational ...

Exfoliation and Analysis of Large-area, Air-Sensitive Two-Dimensional Materials

We describe methods for producing and analyzing large, thin flakes of air-sensitive two-dimensional materials. Thin flakes of layered or van der Waals crystals are produced using mechanical exfoliation, in which layers are peeled off a bulk crystal using adhesive tape. This method produces high-quality flakes, but they are often small and can be hard to find, particularly for materials with relatively high cleavage energies such as black phosphorus. By heating the substrate and the tape, two-dimensional material adhesion to the substrate is promoted, and the flake yield can be increased by up to a factor of ten. After exfoliation, it is necessary to image or otherwise analyze these flakes but some two-dimensional materials are sensitive to oxygen or water and will degrade when exposed air. We have designed and tested a hermetic transfer cell to temporarily maintain the inert environment of a glovebox so that air-sensitive flakes can be imaged and analyzed with minimal degradation. The compact design of the transfer cell is such that optical analysis of sensitive materials can be performed outside of a glovebox without specialized equipment or modifications to existing equipment.

A method for exfoliating large thin flakes of air sensitive two-dimensional materials and safely transporting them for analysis outside of a glovebox is presented.

Pul pul dökülme ve geniş alanlara, analizini hava duyarlı iki boyutlu malzemeleri

We describe methods for producing and analyzing large, thin flakes of air-sensitive two-dimensional materials. Thin flakes of layered or van der Waals ...