Reconfigurable Printed Liquids

Liquids lack the spatial order required for advanced functionality. Interfacial assemblies of colloids, however, can be used to shape liquids into complex, 3D objects, simultaneously forming 2D layers with novel magnetic, plasmonic, or structural properties. Fully exploiting all‐liquid systems that are structured by their interfaces would create a new class of biomimetic, reconfigurable, and responsive materials. Here, printed constructs of water in oil are presented. Both form and function are given to the system by the assembly and jamming of nanoparticle surfactants, formed from the interfacial interaction of nanoparticles and amphiphilic polymers that bear complementary functional groups. These yield dissipative constructs that exhibit a compartmentalized response to chemical cues. Potential applications include biphasic reaction vessels, liquid electronics, novel media for the encapsulation of cells and active matter, and dynamic constructs that both alter, and are altered by, their external environment.     

Reverse engineering approach to appearance-based design of metallic and pearlescent paints

We propose a new approach to interactive design of metallic and pearlescent coatings, such as automotive paints and plastic finishes of electronic appliances. This approach includes solving the inverse problem, that is, finding pigment composition of a paint from its bidirectional reflectance distribution function (BRDF) based on a simple paint model. The inverse problem is solved by two consecutive optimizations calculated in real-time on a contemporary PC. Such reverse engineering can serve as a starting point for subsequent design of new paints in terms of appearance attributes that are directly connected to the physical parameters of our model. This allows the user to have a paint composition in parallel with the appearance being designed.     

利用高分辨辉光放电质谱技术对难熔金属材料进行痕量元素定量和深度剖面分析

直接采样的高分辨辉光放电质谱(GDMS)是当今高纯固体常规分析中可用的高灵敏度分析方法之一。这种多元素分析技术通常用于主量化学成分的定量分析、监测元素质量分数随微米级深度(深度分布)的变化,或用于对多种固体和镀层上肉眼可见体积的高灵敏度的分布研究,包括纯金属、高温合金、陶瓷或其中陶瓷金属。由于GDMS的检测几乎涵盖了所有方法,因此在监测痕量级的多元素含量方面是最具成本优势的。另外,它使对在包含绝缘层和(或)镀层及两者化合物的平面上的高灵敏度的含量深度分布分析成为可能。本文着重介绍直流辉光质谱技术用于监测痕量至超含量元素分析技术目前的进展以及直接采样分析实践中应当采用的策略。     

Complexity analysis of the Pawlak’s flowgraph extension for re-identification in multi-camera surveillance system

The idea of Pawlak’s flowgraph turned out to be a useful and convenient container for a knowledge of objects’ behaviour and movements within the area observed with a multi-camera surveillance system. Utilization of the flowgraph for modelling behaviour admittedly requires certain extensions and enhancements, but it allows for combining many rules into a one data structure and for obtaining parameters describing how objects tend to move through the supervised area. The main aim of this article is presentation of the complexity analysis of proposed modification of flowgraphs. This analysis contains considerations of issues such as memory efficiency and computational complexity of operations on the flowgraph. The measures related to space and time efficiency were also included.     

Relative Cation-Anion Diffusion in Alkyltriethylammonium-Based Ionic Liquids

¹⁹F Nuclear Magnetic Resonance spin-lattice relaxation experiments have been performed for a series of ionic liquids including the same anion, bis(trifluoromethanesulfonyl)imide, and cations with alkyl chains of different lengths: triethylhexylammonium, triethyloctylammonium_, decyltriethylammonium, dodecyltriethylammonium, decyltriethylammonium, and hexadecyltriethylammonium. The experiments have been carried out in a frequency range of 10 kHz to 10 MHz versus temperature. A thorough analysis of the relaxation data has led to the determination of the cation–anion as a relative translation diffusion coefficient. The diffusion coefficients have been compared with the corresponding cation–cation and anion–anion diffusion coefficients, revealing a correlation in the relative translation movement of the anion and the triethylhexylammonium, triethyloctylammonium, decyltriethylammonium, and dodecyltriethylammonium cations, whereas the relative translation diffusion between the anion and the cations with the longer alkyl chains, decyltriethylammonium and hexadecyltriethylammonium, remains rather uncorrelated (correlated to a much lesser extent).     

Stable time step estimates for mesh‐free particle methods

Real‐time computational biomechanics for medicine usually uses explicit time integration, because of its efficiency and suitability for parallel implementation. Explicit time integration is only conditionally stable and therefore requires an estimation of the maximum stable time step that can be used. In this paper we develop a method of estimating the stable time step for mesh‐free particle methods for a specific case of mass lumping: the mass associated with an integration point is distributed equally to all nodes found in the support domain of that integration point. Two estimates of the stable time step for each integration point are developed: one that is very accurate but more costly to compute and one less accurate but easier to implement. The results are also valid for the FEM and beyond computational biomechanics for medicine. Copyright © 2012 John Wiley & Sons, Ltd.     

A case study towards validation of global illumination algorithms: progressive hierarchical radiosity with clustering

In this paper, we present an efficient global illumination technique, and then we discuss the results of its extensive experimental validation. The technique is a hybrid of cluster-based hierarchical and progressive radiosity techniques, which does not require storing links between interacting surfaces and clusters. We tested our technique by applying a multistage validation procedure, which we designed specifically for global illumination solutions. First, we experimentally validate the algorithm against analytically derived and measured real-world data to check how calculation speed is traded for lighting simulation accuracy for various clustering and meshing scenarios. Then we test the algorithm performance and rendering quality by directly comparing the virtual and real-world images of a complex environment.     

Potential of Bacterial Cellulose Chemisorbed with Anti-Metabolites, 3-Bromopyruvate or Sertraline,to Fight against Helicobacter pylori Lawn Biofilm

Helicobacter pylori is a bacterium known mainly of its ability to cause persistent inflammations of the human stomach, resulting in peptic ulcer diseases and gastric cancers. Continuous exposure of this bacterium to antibiotics has resulted in high detection of multidrug-resistant strains and difficulties in obtaining a therapeutic effect. The purpose of the present study was to determine the usability of bacterial cellulose (BC) chemisorbed with 3-bromopyruvate (3-BP) or sertraline (SER) to act against lawn H. pylori biofilms. The characterization of BC carriers was made using a N2 adsorption/desorption analysis, tensile strength test, and scanning electron microscopy (SEM) observations. Determination of an antimicrobial activity was performed using a modified disk-diffusion method and a self-designed method of testing antibacterial activity against biofilm microbial forms. In addition, bacterial morphology was checked by SEM. It was found that BC disks were characterized by a high cross-linking and shear/stretch resistance. Growth inhibition zones for BC disks chemisorbed with 2 mg of SER or 3-BP were equal to 26.5–27.5 mm and 27–30 mm, respectively. The viability of lawn biofilm H. pylori cells after a 4-h incubation with 2 mg SER or 3-BP chemisorbed on BC disks was ≥4 log lower, suggesting their antibacterial effect. SEM observations showed a number of morphostructural changes in H. pylori cells exposed to these substances. Concluding, SER and 3-BP chemisorbed on BC carriers presented a promising antibacterial activity against biofilm H. pylori cells in in vitro conditions.     

Influence of tapes’ properties on the laser cutting process

Ceramic tapes are used to build 3-dimensional components and microsystems in layer manufacturing. The tapes are individually printed and structured before being stacked and laminated. The structuring process of the tapes affects the maximal resolution of fluidic channels, suspended bridges and beams, which in turn determines the scale of miniaturization of the produced components. The aim of this paper is to investigate if the tape composition can be optimized to improve the cutting resolution of laser cutting, which is a very flexible tool for micromachining. Using the Siemens star pattern, the laser cutting resolution was measured for alumina green tapes of different binder compositions with different laser settings. For all tapes the resolution was better the higher the laser beam velocity. At higher velocity though, a higher number of cutting cycles is necessary to cut the tape. The laser cutting resolution depends on the binder composition, but the laser parameters must also be optimized to achieve high cutting resolution.