scholarly journals Hierarchical living assembly: fabrication and visualization of multiblock microstructures

Author(s):  
Xiujuan Shi ◽  
Jun Zhang ◽  
Junkai Liu ◽  
Xueqian Zhao ◽  
Haoran Wang ◽  
...  

Nature possesses a powerful ability to assemble multiple complex structures to fabricate hierarchical biological structures in a living-assembled way. However, it is still a huge challenge for artificial systems to fabricate and characterize hierarchical living assemblies with well-defined and controllable but complex structures. In this work, we proposed a new concept for the fabrication of multiblock fluorescent microcolumns, which relies on the cooperation between the controllable host–guest complexation based on cucurbit[8]uril (CB[8]) and the living assembly of nanotubular supramolecular polymers composed of CB[8] and NaBr in aqueous solution. By using the complexation of CB[8] with different guest numbers of luminogens with aggregation-induced emission (AIEgens) characteristics, and the difference in affinity between CB[8] and different types of AIEgens, the concentration-controlled and self-sorting-controlled sequential living assembly are realized, respectively. Correspondingly, multiblock fluorescent microcolumns with different fluorescence emission are fabricated, and the molecular structure of each fluorescent block is analyzed by single crystal X-ray diffraction measurement. In addition, the living assembly of multiblock fluorescent microcolumns is visualized, understood, and regulated with the aid of AIEgens. The method developed here is expected to be extended to more guest molecules of CB[8] and also provides a referential crystallization method for CB[8]-based complexes.

1972 ◽  
Vol 16 ◽  
pp. 344-353 ◽  
Author(s):  
Carol J. Kelly ◽  
E. Eichen

AbstractThe system to be described includes hardware and software for the on-line computer control of the X-ray diffraction measurement of residual stress. This determination involves accurately measuring the angles at which a back-reflection line is diffracted, first by diffracting planes parallel to the sample surface, and then by planes at an angle (ψ) to the sample surface. The residual stress is calculated from the difference in the two measured diffraetion angles. The procedure executed by the computer consists of locating the peaks, selecting three angles for collection of X-ray counts, correcting the measured counts, fitting the equi-angular intensity measurements to a three-point parabola, calculating the peak angles, calculating the residual stress from the measured angles and typing a report. This automation has eliminated the tedium of the manual X-ray data accumulation and of the residual stress calculation. The online control has also permitted improvements in the technique not practicable with the manually performed measurement of residual stress.


2014 ◽  
Vol 996 ◽  
pp. 175-180 ◽  
Author(s):  
Rasha Alkaisee ◽  
Ru Lin Peng

For X-Ray Diffraction Measurement of Depth Profiles of Residual Stress, Step-Wise Removal of Materials has to be Done to Expose the Underneath Layers to the X-Rays. this Paper Investigates the Influence of Layer Removal Methods, Including Electro-Polishing in Two Different Electrolytes and Chemical Etching, on the Accuracy of Residual Stress Measurement. Measurements on Two Shot-Peened Steels Revealed Large Discrepancy in Subsurface Distributions of Residual Stress Obtained with the Respective Methods. Especially, the Chemical Etching Yielded much Lower Subsurface Compressive Stresses than the Electro-Polishing Using a so Called AII Electrolyte. the Difference was Explained by the Influence of the Different Layer Removal Methods on the Microscopic Roughness.


1998 ◽  
Vol 52 (1) ◽  
pp. 54-63 ◽  
Author(s):  
Brigitte Wopenka ◽  
John J. Freeman ◽  
Tony Nikischer

Laser Raman microprobe spectra of the natrolite group of zeolites (fibrous hydrous network aluminosilicates) can be used to unambiguously distinguish among the six members of this group, which is difficult by visual, microscopic, and X-ray diffraction methods. The natrolite group of zeolites includes the following minerals: natrolite (Na2Al2Si3O10·2H2O), scolecite (CaAl2Si3O10·3H2O), mesolite (Na2Ca2Al6Si9O30·8H2O), thomsonite (NaCa2Al5Si5O20·6H2O), gonnardite (Na2CaAl4Si6O20·7H2O), and edingtonite (BaAl2Si3O10·4H2O). Accurate locations of peak maxima are given, and complete Raman spectra (from 100 to 4000 Δcm−1) are shown for each mineral. The individual members of this structurally very similar group of minerals can be identified on the basis of the exact Raman peak positions of the two strongest bands near 440 and 535 Δcm−1, the number and positions of weaker bands, and the difference in the dependence of peak intensities upon beam polarization direction. However, the minerals can be especially easily identified on the basis of their strikingly different Raman spectral patterns in the O–H stretching region (3000–3700 Δcm−1). The number and width of peaks in this spectral region correlate with the three different types of framework structures that occur among the natrolite group minerals.


2021 ◽  
Vol 3 (2) ◽  
pp. 01-08
Author(s):  
Ekta Chandel ◽  
Vivek Vijay

Yagya kund construction is the outcome of great research of ancient India. Indian scripture has given very sophisticated Vedic mathematical formulations for construction of Yagya kund. There are different types of shapes described for Yagya kund; Circular & Lotus, Semi-circular, Vulvar, Trigonal, Square, Pentagonal, Hexagonal, Heptagonal, Octagonal. Irrespective of shapes,all these Yagya kunds have same surface area. Based on the fact given in the literature, 1000 offerings (ahutis) require construction of BhuHastatmakaKund (1 hand or 24 angul long). In addition, height of the all one-hand long kunds are same. Hence, the present research tests the hypothesis that the volume should be same for all different shaped kunds. In the present study, the volume of 1 hast Yagya kund (24 angul) for all these shapes is calculated using the dimensions given in the scripture using available simple available mathematical formulas. Volume of all these kunds is compared with circular shape kund. The difference in the volume of different shapes is foundbelow 0.3% in all the kunds except for vulvar, pentagonal and octagonal shapes which is observed to be 7.48%, 1.76% and 2.83% respectively. The difference isdueto inappropriate mathematical formula for these complex structures having different angles in the slants and multiple sides of the bases.


Author(s):  
Y. H. Liu

Ordered Ni3Fe crystals possess a LI2 type superlattice similar to the Cu3Au structure. The difference in slip behavior of the superlattice as compared with that of a disordered phase has been well established. Cottrell first postulated that the increase in resistance for slip in the superlattice structure is attributed to the presence of antiphase domain boundaries. Following Cottrell's domain hardening mechanism, numerous workers have proposed other refined models also involving the presence of domain boundaries. Using the anomalous X-ray diffraction technique, Davies and Stoloff have shown that the hardness of the Ni3Fe superlattice varies with the domain size. So far, no direct observation of antiphase domain boundaries in Ni3Fe has been reported. Because the atomic scattering factors of the elements in NijFe are so close, the superlattice reflections are not easily detected. Furthermore, the domain configurations in NioFe are thought to be independent of the crystallographic orientations.


Author(s):  
Ni Ketut Mirahayuni ◽  
Susie Chrismalia Garnida ◽  
Mateus Rudi Supsiadji

Abstract. Translating complex structures have always been a challenge for a translator since the structures can be densed with ideas and particular logical relations. The purpose of translation is reproducing texts into another language to make them available to wider readerships. Since language is not merely classification of a set of universal and general concept, that each language articulates or organizes the world differently, the concepts in one language can be radically different from another. One issue in translation is the difference among languages, that the wider gaps between the source and target languages may bring greater problems of transfer of message from the source into the target languages (Culler, 1976). Problematic factors involved in translation include meaning, style, proverbs, idioms and others. A number of translation procedures and strategies have been discussed to solve translation problems. This article presents analysis of complex structures in scientific Indonesian, the problems and effects on translation into English. The study involves data taken from two research article papers in Indonesian to be translated into English. The results of the analysis show seven (7) problems of Indonesian complex structures, whose effect on translation process can be grouped into two: complex structures related to grammar (including: complex structure with incomplete information, run-on sentences, redundancy , sentence elements with inequal semantic relation, and logical relation and choice of conjunctor) and complex structures related to information processing in discourse (including: front-weight- structure and thematic structure with changes of Theme element). Problems related to grammar may be solved with language economy and accuracy while those related to discourse may be solved with understanding information packaging patterns in the target language discourse. Keywords: scientific language, complex structures, translation


2020 ◽  
Vol 17 (6) ◽  
pp. 472-478
Author(s):  
Wei-tao Gong ◽  
Wei-dong Qu ◽  
Guiling Ning

Two pyridinium amide-based receptors L1 and L2 with a small difference of H-bond position of the amide have been synthesized and characterized. Interestingly, they exhibited a huge difference in sensing towards AcO- and H2PO4 -, respectively. Receptor L1 was found to be ‘naked-eye’ selective for AcO- anions, while receptor L2 showed clear fluorescence enhancement selective to H2PO4 - anion. The recognition ability has been established by fluorescence emission, UV-vis spectra, and 1HNMR titration.


2008 ◽  
Vol 73 (1) ◽  
pp. 24-31
Author(s):  
Dayu Wu ◽  
Genhua Wu ◽  
Wei Huang ◽  
Zhuqing Wang

The compound [Cd(4,4'-bpy)2(H2O)2](ClO4)2·(L)2 was obtained by the reaction of Cd(ClO4)2, bis(1-pyrazinylethylidene)hydrazine (L) and 4,4'-bipyridine in aqueous MeOH. Single-crystal X-ray diffraction has revealed its two-dimensional metal-organic framework. The 2-D layers superpose on each other, giving a channel structure. The square planar grids consist of two pairs of shared edges with Cd(II) ion and a 4,4'-bipyridine molecule each vertex and side, respectively. The square cavity has a dimension of 11.817 × 11.781 Å. Two guest molecules of bis(1-pyrazinylethylidene)hydrazine are clathrated in every hydrophobic host cavity, being further stabilized by π-π stacking and hydrogen bonding. The results suggest that the hydrazine molecules present in the network serve as structure-directing templates in the formation of crystal structures.


Author(s):  
Zhijie Chua ◽  
Bartosz Zarychta ◽  
Christopher G. Gianopoulos ◽  
Vladimir V. Zhurov ◽  
A. Alan Pinkerton

A high-resolution X-ray diffraction measurement of 2,5-dichloro-1,4-benzoquinone (DCBQ) at 20 K was carried out. The experimental charge density was modeled using the Hansen–Coppens multipolar expansion and the topology of the electron density was analyzed in terms of the quantum theory of atoms in molecules (QTAIM). Two different multipole models, predominantly differentiated by the treatment of the chlorine atom, were obtained. The experimental results have been compared to theoretical results in the form of a multipolar refinement against theoretical structure factors and through direct topological analysis of the electron density obtained from the optimized periodic wavefunction. The similarity of the properties of the total electron density in all cases demonstrates the robustness of the Hansen–Coppens formalism. All intra- and intermolecular interactions have been characterized.


Coatings ◽  
2021 ◽  
Vol 11 (3) ◽  
pp. 354
Author(s):  
Tim Tofan ◽  
Rimantas Stonkus ◽  
Raimondas Jasevičius

The aim of this research is to investigate related effect of dyeability to linen textiles related to different printing parameters. The study investigated the change in color characteristics when printing on linen fabrics with an inkjet MIMAKI Tx400-1800D printer with pigmented TP 250 inks. The dependence of color reproduction on linen fabrics on the number of print head passes, number of ink layers to be coated, linen fabric density, and different types of linen fabric was investigated. All this affects the quality of print and its mechanical properties. The change in color characteristics on different types of linen fabrics was determined experimentally. We determine at which print settings the most accurate color reproduction can be achieved on different linen fabrics. The difference between the highest and the lowest possible number of head passages was investigated. The possibilities of reproducing different linen fabric colors were determined.


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