Interplay between shape and composition in bimetallic nanoparticles revealed by an efficient optimal-exchange optimization algorithm

Despite the large relevance of bimetallic metal nanoparticles for heterogeneous catalysis, the relation between their shape and elemental composition remains elusive. Here, we investigate this relationship by implementing and applying global optimization methods enhanced with a novel optimal-exchange algorithm. In particular, we determine the lowest energy chemical orderings for PtAu nanoparticles, revealing that the most stable shape changes from highly symmetric structures for pure particles to distorted and less symmetric shapes for intermediate compositions. The presented method leverages the local atomic contributions to an empirical surrogate energy expression to identify optimal atom exchanges. This also allows us to pinpoint the origin of the stability of distorted shapes, revealing a favorable energy trade-off when over-coordinating Pt and under-coordinating Au upon distorting the particle shape.

Design of Four-Patch Multi-Stable Composite Laminates for Shape Morphing Applications

Thin bistable composite laminates can be used for shape morphing applications by virtue of their material properties and asymmetric ply layup. These laminates are called bistable because they can be snapped into two or more stable shapes. A single bistable patch can result in simple cylindrical shapes and when multiple such patches are assembled into a single multi-patch laminate they result in more complex shapes and multiple stable shapes that can find wide practical use in shape morphing applications. Analytical models exist that can approximate the stable shapes of the laminates from the input of material properties and laminate geometry. And these models correlate with FEA and experiment to a satisfactory degree and could be used for the design of multi patch laminates. In this research, we make use of these analytical models that solve for a four-patch grid laminate and create a design method based on optimization to solve the reverse problem to arrive at the laminate parameters given the target shape(s). Two approaches are presented wherein one targets a single stable shape and the other targets two stable shapes which are the shapes before and after snap through. This work would be useful to understand how multi-patch laminates could be designed using optimization.

IMPROVEMENT OF THE TECHNOLOGY AND FORMULATION OF FINISHING SEMI-FINISHED PRODUCT FOR FLOUR CONFECTIONERY PRODUCTS FOR DIETARY PROPHYLACTIC PURPOSES

Совершенствование структуры ассортимента кондитерских изделий направлено на увеличение выработки продукции повышенной пищевой ценности. Исследована возможность замены сливочного масла в рецептуре отделочного кремового полуфабриката для мучных кондитерских изделий сливками животного происхождения для снижения его калорийности. Объектом исследования были образцы сливочного крема «Шарлотт», изготовленного на основе стандартной рецептуры, но с заменой сливочного масла сливками жирностью 33%. Для стабилизации структуры крема добавляли яблочный пектин в количестве 1,5% к массе образца. Оптимизацию показателей сбалансированности состава и органолептических свойств проводили с помощью прикладных математических программ Mathcad 15.0 и Statistica 13.0. На основе полученных данных разработаны технология и рецептуры отделочных кремовых полуфабрикатов с добавлением какао-порошка и без него. Органолептическая оценка показала, что разработанные кремовые полуфабрикаты имеют необходимые показатели качества – пластичную текстуру, устойчивую форму, приятный, без посторонних запахов вкус. Установлено, что калорийность разработанных образцов крема с заменой сливочного масла сливками жирностью 33% на 23% ниже, чем калорийность крема «Шарлотт», приготовленного по традиционной рецептуре. Включение в рецептуру крема яблочного пектина позволяет рекомендовать разработанный отделочный полуфабрикат для производства мучных кондитерских изделий функционального назначения. Improvement the structure of the range of confectionery products is aimed at increasing the production of products of increased nutritional value. The possibility of replacing butter in the formulation for finishing cream semi-finished products for flour confectionery products with animal cream to reduce its caloric content is investigated. Samples of butter cream «Charlott», made on the basis of a standard formulation, but with the replacement of butter with cream with a fat content of 33%, were the object of the study. To stabilize the structure of the cream apple pectin was added in an amount of 1,5% by weight of the sample. Optimization of indicators of balance of composition and organoleptic properties was performed using applied mathematical programs Mathcad 15.0 and Statistica 13.0. Based on the data obtained, the technology and formulations for finishing cream semi-finished products with and without cocoa powder were developed. Organoleptic evaluation showed that the developed cream semi-finished products have the necessary quality indicators – plastic texture, stable shape, pleasant, odorless taste. It is established that the caloric developed cream samples with replacement of butter cream 33% fat is 23% lower than the calorie content of the cream «Charlott», made on the basis of a standard formulation. The inclusion of apple pectin in the cream formulation allows us to recommend the developed finishing semi-finished product for the production of functional flour confectionery products.

TO THE QUESTION ABOUT TWO CULTURAL-CHRONOLOGICAL GROUPS OF FLINT INVENTORY OF THE KRASNY GORODOK SITE

The Krasny Gorodok site, explored in the late 1980s, has long attracted the attention of specialists in the Neolithic. There archaeologists discovered a small but very interesting collection of ceramics. At the same time, the flint complex of the site raised several questions even at the stage of primary comprehension of the material, and researchers made assumptions about the presence of two cultural-chronological groups of flint materials in the complex of the site. In connection with the expansion of the source base on the Early Neolithic and Mesolithic of the forest-steppe Volga region, as well as the acquisition of a significant array of natural science data, it became necessary to verify the conclusions drawn by more than a quarter of a century ago. In particular, the question of the homogeneity of the flint collection of the site and the possibility of identifying an early admixture remains relevant. During the reanalysis of the flint collection of the Krasny Gorodok site, about 600 units of stone artifacts were examined. This complex was divided into two groups depending on the color and quality characteristics of the flint. The first group is represented by artifacts made of high-quality flint of gray color and its various shades. The second group includes artifacts made of low-grade colored flint, mainly brown and of various shades of brown, without a stable shape. The first group is characterized by a large orientation towards obtaining plates of a regular shape and their relatively high specific gravity (23%). In addition, this type of raw material was used to make all the angular cutters on the plates found at the site and, in general, most of the tools were made from plate blanks. The collection of tools made of colored flint is less indicative, however, one can state a lesser orientation towards obtaining plates from this type of raw material and, predominantly, their irregular shape, while few tools were made on flakes and chips. In our opinion, the marked differences between the first and second groups of stone products from the site are of a cultural and chronological nature. The first group of flint, in terms of raw materials, shape and technique of making tools and applying retouching on them, can be attributed to the era of the late Mesolithic of the forest-steppe Volga region. The second group, in terms of the nature of the raw materials and the morphology of tools, belongs to the Early Neolithic.

Reducing the Impact of Wind Load with Shape of High Rise Buildings

Recent Years, Many high rise buildings are being constructed across the world due to the increase in population. From the design point of view, lateral load such as earthquake and wind load should be taken into consideration while designing process. Architectural design of buildings sometimes leads towards difficult and unusual shape that challenges structural designers. The objective of this study is to assess the building behavior when subjected to wind load. To achieve this objective, different shapes of building such as pentagonal, triangular and circular building are assessed for stability. Parameters such as storey drift and lateral displacement are considered in order to find most effective and stable shape. The computer program ETABS is used for analysis. As the height of the building increases, wind load effect becomes significant and should be considered for designing. This could also be achieved by selecting most stable shape and appropriate structural system for tall buildings.

3D Shape Prediction of a Paper Model for a Brassiere Cup Consisting of Multiple Polygonal Patterns

A general method is proposed to predict the shape of a paper model of a brassiere cup. A brassiere cup consists of several cloth and wire parts and the shapes of cloth parts are determined by repeating creation of a paper cup model, check of its 3D shape, and modification of 2D shapes of parts. For efficient design of a brassiere cup, prediction of its 3D shape with a simulation is required. The deformed shape of a paper part is represented as a single or multiple developable surfaces. So, a model that can represent a part both as a single surface and as multiple surfaces is proposed. Which case is selected depends on the magnitude of the potential energy of the part in each case. The potential energy of the part and geometric constraints imposed on the part are formulated based on the model. Minimizing the potential energy under geometric constraints derives the stable shape of the part in either case. Furthermore, our proposed method can be applied to prediction of the paper cup model consisting of parts with complex shapes.