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.

열수 방법을 사용하여 α-ZrP를 1. 합성 <ol><li> 지르 코닐 클로라이드 수화물의 6g (ZrOCl이 ·이 8H 2 O) 3.75 ㎖를 150 ㎖의 (DI) 탈 이온수에서 둥근 바닥 플라스크를 녹인다. </li><li> 격렬한 교반 (DI) 탈 이온수 8.25 ml를 추가하여 다음 단계 1.1에서 제조 된 ZrOCl 2 용액에 15 M 인산 (H 3 PO 4)를 적가의 48 ML을 추가합니다. </li><li> 80 ml의 부피의 테프론 라이닝 압력 용기에 겔상 혼합물을 수득 붓는다. 스테인레스 스틸 쉘 및 덮개, 압력 플레이트로 이루어지는 수열을 오토 클레이브에 용기를 배치하고 잘 조인다. </li><li> 24 시간 동안 200 ° C에서 대류 오븐에 열수 오토 클레이브를 놓습니다. </li><li> 반응 후, 오토 클레이브 수열 주변 냉각하에 실온에서 8 시간 동안 냉각 할 수있다. </li><li> 2에서 원심 분리기를 사용하여 냉각 후 원심 분리 관에 α-ZrP를 디스크를 수집,10 분 동안 500 XG. 상등액은 부식 반응 인산을 포함하고 있기 때문에 폐기 용기에 액체를 수집 부. <ol><li> 그 후, 다시 10 분 동안 2,500 XG에서 1 분 원심 분리기에 대한-ZrP를을 α 물 40 ml의 소용돌이를 추가합니다. 산의 모든 씻어되어 있는지 확인하기 위해이 단계를 3 번​​ 반복합니다. </li></ol></li><li> 다음 65 ° 8 시간 동안 C와의 오븐에서 건조 ZrP를 물 끈적 끈적한 혼합물 봉과 박격포를 사용하여 분쇄. </li></ol> 역류성 방법에 의한 α-ZrP를 2. 합성 <ol><li> 150 ml의 12 M 인산 산 50 ml의 둥근 바닥 플라스크에 · 8H 2 O ZrOCl 2 6g을 섞는다. </li><li> 단계 2.1에서 제조 한 혼합물을 24 시간 동안 94 ℃에서 오일 조에서 환류한다. </li><li> 단계 1.6 DI 물과 같은 프로토콜은 다음 세 번 제품을 세척 한 후 8 시간 동안 65 ° C의 오븐에서 건조시켰다. </li><li> 유봉과 박격포, 주식 F를 사용하여 분말로 건조 부피가 큰 샘플을 갈기이상 사용합니다. </li></ol> 마이크로 웨이브를 이용한 방법에 의한 α-ZrP를 3. 합성 <ol><li> 12 M 인산 용액 9 ㎖ 중에 ZrOCl 2 · 8H2O 1 g을 추가하고, 20 mL의 섬광 바이알에 잘 생성 된 혼합물을 교반한다. </li><li> 마이크로파 반응기를 위해 특정 된 10 ㎖ 유리 용기에, 상기 혼합물을 5 mL를 붓는다. </li><li> 150 ° C, 300 psi에서 압력 한계로 설정하고, 반응 온도는 반응이 1 시간 동안 일어날 수. </li><li> 반응 후, 유리 용기를 약 15 분 동안 냉각 한 후 산 세정 및 α-ZrP를 결정을 건조하는 단계 1.6-1.7에서와 동일한 절차를 수행하겠습니다. </li></ol> 단일 층으로 계층화 된 α-ZrP를 4. 각질 제거 <ol><li> 20 mL의 섬광 바이알에 DI 물 10 ㎖로 α-ZrP를 1 g의 분산. </li><li> 적어도 40 초 동안 그와 소용돌이에 TBAOH (40 중량. %)의 2.2 ML을 추가합니다. TBAOH 1로 유지된다 : ZR의 몰비 주목 한. </li><li> 1 ~ 2 시간 동안 생성 된 농축 현탁액을 초음파 처리 및 TBA + 이온과 결정의 완전한 박리의 전체 인터 할 수 있도록 3 일간 둡니다. 임의로, 농축 된 현탁액을 더 박리를 얻는 물 (2 내지 3 배 희석)로 희석 될 수있다. </li><li> 바닥에 침전 부분적으로 박리 된 결정을 제거하기 위해 1 시간 동안 높은 회전 속도 (2500 XG)에서 박리 된 샘플을 원심 분리기. 또 용기 (ZrP를 박리) 상부 수집하고, 침전은 발견되지 않을 때까지 과정을 반복한다. </li></ol>

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There is nothing to disclose.

환류 법에서는 균일 한 직경 및 두께의 α-ZrP를 소형화하기위한 좋은 선택이다. 열수 방법과 유사하게, 환류 방법이 준비 시간에 의해 제한된다. 일반적으로, 결정 성장을위한 긴 시간이 걸린다. 환류 법에 필요한 더 긴 반응 시간은보다 큰 크기 nanodisks 초래할 수있다. 박리 nanodisks의 평균 크기는 동적 광산란 (DLS)에 의해 측정된다. 본 연구에서는 박리 ZrP를 nanodisks의 크기는 19...

디스코 틱 콜로이드 점토, 아스 팔텐, 적혈구 및 진주층 형태 자연스럽게 풍부. 폴리머 나노 복합체 (1) 생체 모방 재료 기능성 멤브레인이, 디스코 틱 액정 성 시험 (3, 4)가 디스크 형 콜로이드 nanodisks에 기초하여 개발된다 피커링 에멀젼 안정제를 포함한 많은 설계 시스템의 응용의 범위. 균일 성 및 낮은 분산과 Nanodisks는 단계와 액정의 변환을 공부하는 것이 중요합니다. 지르코늄 인산 (ZrP를)는 잘 정렬 된 층 구조 및 제어 종횡비 (직경 위에 두께)와 합성 nanodisks이다. 따라서, ZrP를 다른 합성 탐사 디스코 틱 액정 시스템의 기본적인 이해를 확립 돕는다. ZrP를의 구조는 1964 년 5 클리어하고 Stynes에 의해 밝혀졌다. ZrP를 열수의 층상 결정의 합성 및환류 방법은 일반적으로 6,7을 채택하고 있습니다. 환류 방법은 동일한 지속 시간에 대한 작은 결정을 제공하는 동안 열수 방법은 400에서 25 % (6) 내에서 1,500 nm의 분산에 이르기까지 크기에 좋은 제어 할 수 있습니다. 마이크로파 가열은 나노 물질 8의 합성을위한 유망한 방법으로 입증되었습니다. 그러나, 전자 레인지를 이용한 경로에 따라 ZrP를의 합성을 설명하는 어떤 서류가 없습니다. 사이즈, 종횡비, 및 수열 법에 의한 결정 성장기구를 통해 효과적인 제어는 체계적 기 (6)에 의해 연구되었다. ZrP를 쉽게 수성 현탁액의 단일 층으로 박리 할 수 있고, 박리 ZrP를 잘 쳉의 그룹 3,9-13의 액정 재료로서 확립되었다. 지금까지, 다양한 직경 박리 ZrP를의 nanodisks는 다른 종횡비가 큰 ZrP를 낮은 콘에서 I (등방성) -N (네마 틱) 전환을 한 것으로 결론을 연구 한 말작은 ZrP를 3에 비해 자기 중심. 네마 틱 액정상의 ​​형성에 분산 3 염 (9) 및 온도 (10, 11)의 효과 또한 고려되었다. 또한, 이러한 sematic 액정 상 등의 다른 단계는도 13, 14을 조사 하였다. 이 글에서, 우리는 콜로이드 ZrP를의 nanodisks 서스펜션의 실험 실현을 보여줍니다. 계층화 ZrP를 결정은 다양한 방법을 통해 합성 한 후, 단층을 수득 nanodisks 수성 매질에서 박리된다. 끝으로,이 시스템에 의해 전시 된 액정 상 전이를 나타낸다. 이러한 디스크의 주목할만한 특징은 직경 비율 두께는 디스크 (3)의 크기에 따라 0.05 0.0007의 범위에있는 그들의 높은 이방성 특성이다. 고도의 이방성 단층 nanodisks는 nanodisks의 현탁액에 위상 전환을 연구하는 모델 시스템을 설정합니다.

<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.

그림 1A-C 쇼 각각 수열, 환류, 전자 렌지를 이용한 방법에서 얻은 α-ZrP를 nanodisks의 SEM 이미지. 그것은 α-ZrP를 nanodisks 모양과 합성 조건과 준비 방법에 따라 서로 다른 두께의 육각형 표시하는 것이 관찰되었다. 우리 그룹 6에서 이전에보고 된 연구에서 결정 성장 시간 48 시간 상기 들면 디스크의 에지가 선명해질 것을 암시한다. 통상적으로, 환류 법 수...

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.

합성 및 디스코 틱 지르코늄 인산염의 각질 제거는 콜로이드 액체 크리스탈을 구하는

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

synthesis-exfoliation-discotic-zirconium-phosphates-to-obtain

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Chemistry

8.4K 조회수.  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. 

비디오: 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.

뉴 클레오 사이드 트리 포스페이트 - 합성에서 생화학 적 특성에

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

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화학

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.

이집트 블루와 한 블루, 알칼리 지구 구리 실리케이트 계 안료의 각질 제거

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.

콜로이드 프로브 Nanoscopy을 사용하여 입자 간 상호 작용의 양적 및 질적 시험

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-배럴 외부 막 단백질의 구조 결정을 향해 - 구축해에서 결정에

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.

이단 티올 레이트 반응을 이용하여 프로그래밍 주쇄 액정 엘라스토머의 합성

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.

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.

분자 재료를에서: 할로겐 결합을 통해 새로운 이오니아 액체 크리스탈 엔지니어링

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.

면 대 면 모양 이방성 콜 로이드 카드뮴 칼코게나이드 Nanostructures의 연결

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.

Photoresponsive 액정의 구조 역학을 관찰을 위한 새로운 기술

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.

각 질 제거 및 큰 지역의 분석 공기 과민 한 2 차원 재료

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