Types Of Structures Research Articles

Insertion-deletions are depleted in protein regions with predicted secondary structure.

A fundamental goal in evolutionary biology and population genetics is to understand how selection shapes the fate of new mutations. Here we test the null hypothesis that insertion-deletion events (indels) in protein coding regions occur randomly with respect to secondary structures. We identified indels across 11,444 sequence alignments in mouse, rat, human, chimp, and dog genomes, then quantified their overlap with four different types of secondary structure - alpha helices, beta strands, protein bends, and protein turns - predicted by deep-learning methods of AlphaFold2. Indels overlapped secondary structures 54% as much as expected, and were especially under-represented over beta strands, which tend to form internal, stable regions of proteins. In contrast, indels were enriched by 155% over regions without any predicted secondary structures. These skews were stronger in the rodent lineages compared to the primate lineages, consistent with population genetic theory predicting that natural selection will be more efficient in species with larger effective population sizes. Nonsynonymous substitutions were also less common in regions of protein secondary structure, although not as strongly reduced as in indels. In a complementary analysis of thousands of human genomes, we showed that indels overlapping secondary structure segregated at significantly lower frequency than indels outside of secondary structure. Taken together, our study shows that indels are selected against if they overlap secondary structure, presumably because they disrupt the tertiary structure and function of a protein.

Superconductivity in breathing kagome-structured C14 laves phase XOs2(X = Zr,Hf)

Abstract Recently, the emergence of superconductivity in kagome metals has generated significant interest due to its interaction with flat bands and topological electronic states, which exhibit a range of unusual quantum characteristics. This study thoroughly investigates largely unexplored breathing
Kagome structure C14 laves phase compounds XOs2 (X = Zr, Hf) by XRD, electrical transport, magnetization, and specific heat measurements. Our analyses confirm the presence of the MgZn2- type structure in ZrOs2 and HfOs2 compounds, exhibiting type-II superconductivity with critical temperature (TC) values of 2.90(3) K and 2.69(6) K, respectively. Furthermore, specific heat measurements
and an electron-phonon coupling constant suggest the presence of weakly coupled BCS superconductivity in both compounds.

Advanced tree-based machine learning methods for predicting the seismic response of regular and irregular RC frames

In this study, predicting the maximum drift ratio (MDR) for two types of structures: 8-story regular (R8) and vertically irregular (IR8) reinforced concrete (RC) frames are focused. To accomplish this, advanced tree-based machine learning (ML) methods, namely Random Forest (RF), eXtreme Gradient Boosting (XGBoost), and Stochastic Gradient Boosting (SGB) are utilized. 2300 ground motion (GM) records, includes twenty-one input parameters and their nonlinear time history analyses results are considered as a dataset. The performance of the RF, XGBoost, and SGB models was examined considering the impact of the data pre-processing issue to test whether the use of data pre-processing approaches in model development could improve the prediction performance of the advanced ML models. Various data pre-processing techniques, including outlier detection using boxplot, missing data imputation using RF, data transformation using log transformation, and feature selection using Hill Climbing are employed as part of ML pipeline. The models' performance is evaluated using six different well-established statistical evaluation metrics. Subsequently, the results are systematically compared to identify the most effective prediction model. Our findings highlight the substantial impact of data pre-processing on the performance of ML models when predicting seismic responses, specifically the MDR of RC frames. Notably, RF consistently outperformed other ML models for both R8 and IR8 structures in the case of the simple ML pipeline strategy and data pre-processing approach. The RF model achieved R2 scores of R2 = 0.87 and R2 = 0.91 on the test data before implementing data pre-processing for R8 and IR8, respectively. After data pre-processing, R2 scores showed an improvement of 12% and 6.22% in the cases of R8 and IR8. In contrast, the performance scores of SGB consistently fell behind those of RF and XGBoost models.

First principles investigation of Li[formula omitted]Si and Li[formula omitted]Sn alloys: Unraveling atomic-scale influences on material properties

Commercial batteries have currently reached their peak specific capacity, which proves insufficient for the ongoing global energy transition. Consequently, there has been a surge of interest in developing new materials over the last decade, especially those based on silicon (Si) and tin (Sn), known for their high capacity. Despite numerous publications highlighting the advantages of these materials, crucial questions remain regarding volume expansion that must be addressed to propose effective solutions and facilitate their widespread commercial application. In this study, density functional theory was employed to investigate the formation of LixM (M = Si, Sn). Our analysis delves into crystal (c-LixM), amorphous (a-LixM), and amorphous slab (s-LixM) configurations during structural optimization calculations, with the aim of comparing and contrasting relevant findings. The exploration encompasses energetic aspects, volume expansion, and electronic properties. The obtained data enables the simulation of lithiation potential curves for each structural type, directly comparable with experimental results of these materials functioning as anodes in lithium-ion batteries. Notably, the volume expansion of a-LixM exhibits non-linear behavior, correlating with characteristic plateaus in the voltage profile curves.

Landing cushioning analysis of new generation heavy airborne armored vehicles

Purpose The purpose of this study is to ensure the successful implementation of a landing cushion for the new generation armored vehicles with significantly enhanced quality. Furthermore, to introduce a high-precision landing cushioning analysis model. Design/methodology/approach To accurately analyze the cushioning performance of the new generation armored vehicles, a nonlinear finite element dynamics model considering the complex travel system was established. The model considered the influence of various nonlinear factors to measure the dynamic response difference between the proposed and traditional models. The cushioning performance of airbags under different landing conditions and their various influence factors were analyzed. Findings The travel system has a large influence on the key points of the vehicle, whose rear end of the upper deck has a larger acceleration fluctuation compared with the traditional model. The increase in the body material stiffness is helpful to reduce this fluctuation. The established nonlinear finite element model can effectively analyze the landing cushioning performance of airborne armored vehicles. The area of the external airbag vent has a large influence on the cushioning performance, and the cushioning system has excellent cushioning performance under various operating conditions. Practical implications This study introduces the travel system, which is ignored by traditional analytical models. The interactions between various types of complex structures are included in the analysis process in its entirety, leading to valuable new conclusions. Quantitatively reveals the analytical errors of traditional simulation models in multiple dimensions and the reasons for their formation. Based on a high-precision simulation model, it is verified that the designed airbag cushioning system has an excellent cushioning effect for the new generation of heavy airborne armored vehicles. Originality/value The novelty of this work comes from the need for smooth landing with low overload for a new type of large-load airborne armored vehicle and provides a high-precision model that quantifies the traditional analytical modeling errors and error principle.

OVERVIEW OF CHANGES IN THE STRUCTURE OF ASSORTMENTS AND COSTS OF BUILDING PROFILES IN UKRAINE

Purpose. The main purpose of the publication is a qualitative and quantitative analysis of the changes associated with the implementation of new standards for rolled steel in recent years in the domestic regulatory framework. Also, an additional purpose is to estimate changes in the cost structure of certain types of rolled metal in Ukraine over the past 5 years. Methodology. In order to achieve the main purpose, both the rolled steel standards currently in force in Ukraine and the canceled previous standards were examined in detail. Comparison of standards for sheet profiles was carried out according to the criteria of the number of standard sizes and the profiles themselves in the standard. Comparison of standards for shaped profiles was carried out according to several criteria – the number of available standard sizes of profiles, the number of profiles themselves, the mass indicators of the largest and smallest profiles, as well as the efficiency indicators (nuclear distance and the square of the radius of inertia) of the largest and smallest profiles according to the standard. To assess changes in the cost structure of assortment profiles of various types, a quantitative comparison of their absolute and relative market value was carried out based on data from open electronic resources for the past 5 years. Findings. At present, in the part of standards for the range of steel products in Ukraine, a systematic and full-fledged update of the regulatory framework is taking place, with the full preservation of our own national heritage. The need to develop and implement a standard for flat hot-rolled broad-banded sheet, specialized and improved standards for hot-rolled bars and for cold-bent square and rectangular profiles, as well as the need to provide the official status of the standard for I-bars with parallel edges of the shelves are the main problematic issues in the part of the assortment normative base at the moment. Originality. In this publication, a theoretical estimation of modern changes in the current normative base of Ukraine, which regulates the issue of the range of steel rolled metal, is presented. In particular, 2 types of sheet metal, 5 types of shaped hot-rolled steel and 3 types of shaped cold-bent profiles, which are the most widely used for steel building structures, were analyzed. The main performance indicators of profiles according to old and new standards are calculated. Practical value. In the practical part of the completed review, changes in the cost structure of the main types of rolled steel over the past 5 years in Ukraine were estimated. The main problematic issues of the current assortment base of Ukraine are separately identified and practical recommendations for their elimination are provided.

High-pressure Phase Transition of Olivine-type Mg2GeO4 to a Metastable Forsterite-III type Structure and their Equation of States

Abstract Germanates are often used as structural analogs of planetary silicates. We have explored the high-pressure phase relations in Mg2GeO4 using diamond anvil cell experiments combined with synchrotron X-ray diffraction and computations based on density functional theory. Upon room temperature compression, forsterite-type Mg2GeO4 remains stable up to 30 GPa. At higher pressures, a phase transition to a forsterite-III type (Cmc21) structure was observed, which remained stable to the peak pressure of 105 GPa. Using a 3rd order Birch Murnaghan fit to the experimental data, we obtained V0 = 305.1 (3) Å3, K0 = 124.6 (14) GPa and K0′ = 3.86 (fixed) for forsterite- and V0 = 263.5 (15) Å3, K0 = 175 (7) GPa and K0′ = 4.2 (fixed) for the forsterite-III type phase. The forsterite-III type structure was found to be metastable when compared to the stable assemblage of perovskite/post-perovskite + MgO, as observed during laser-heating experiments. Understanding the phase relations and physical properties of metastable phases is crucial for studying the mineralogy of impact sites, understanding metastable wedges in subducting slabs and interpreting the results of shock compression experiments.

M2WISH: An easy and efficient protocol for whole‐mount mRNAin situ hybridization that allows 3D cell resolution of gene expression in Arabidopsis thaliana

SUMMARYGene expression analysis is essential for understanding the mechanisms involved in plant development. Here, we developed M2WISH, a protocol based on MicroWave treatment for Wholemount mRNA In Situ Hybridization in Arabidopsis. By permeabilizing tissues without damaging cellular organization this protocol results in high and homogeneous hybridization yields that enable systematic analysis of gene expression dynamics. Moreover, when combined with cellular histochemical staining, M2WISH successfully provides a cellular resolution of gene expression. Thus, we demonstrate the robustness of M2WISH with 10 genes on roots, aerial meristems, leaves, and embryos in the seed. We applied M2WISH to study the spatial dynamics of WUSCHEL (WUS) and CLAVATA3 (CLV3) expression during in vitro meristematic conversion of roots into shoot apical meristems. Thus, we showed that shoot apical meristems could arise from two different types of root structures that differed by their CLV3 gene expression patterns. We constructed 3D cellular representations of WUS and CLV3 gene co‐expression pattern and stressed the variability inherent to meristem conversion. Thus, this protocol generates a large amount of data on the localization of gene expression, which can be used to model complex systems.

Comparative analysis of track damping effect of structure jointly constructed by subway tunnels and high-rise buildings

The joint construction of subways and other public buildings is a relatively newer type of construction. There is little research experience in the vibration characteristics and track damping design for this type of structure. In this study, a field test was adopted to conduct site measurement analysis on the vibration response of the joint construction project consisting of a subway tunnel and a building with typical frame structures. Numerical simulation methods were also adopted to, respectively, assume the use of ordinary tracks and steel-spring floating slab tracks for the subway for the situation where the Cologne-egg high-elastic fasteners were used on the track for damping purposes. Comparisons were performed to analyze the difference in the system vibration response between three different types of track. The results showed that the high-elastic fastener track and floating slab track both have a certain degree of damping effect compared with an ordinary track. Specifically speaking, the former has a damping advantage for frequency bands below 20 Hz, while the latter has the advantage for frequency bands above 20 Hz under the impact of the structural vibration characteristics for this joint construction. For this jointly construction structure, affected by the natural vibration characteristics of the structure, the natural frequency of the floating slab track is within 4 ∼ 10 Hz, and the similar vibration reduction effect can be achieved. This indicates that the structural vibration characteristic of the jointly constructed structure is an important factor determining the appropriate natural frequency of the floating slab track.

Evaluation of Sedimentary Characteristics of the Chang 9 Oil Layer Formation in the Yanchang Formation, Ordos Basin

Shallow-water deltas are a subject of sedimentary research and represent a significant target for oil and gas exploration. The Yanchang Formation of the Triassic in the Ordos Basin comprises numerous shallow-water delta blocks. This paper addresses the core issues pertaining to the sedimentary facies, sedimentary characteristics and sand body distribution of the Chang 9 oil layer formation of the Upper Triassic in the Ordos Basin. Guided by the relevant theories and methods of contemporary sedimentology and sedimentary geology, the reservoir characteristics are described and studied in detail through ordinary thin sections, cast thin sections, graphical representations of particle size and scanning electron microscopy experiments. The experimental results indicate that the porosity in the study area ranges from 3% to 12% and that the permeability is between 0 and 1.5 × 10−3 μm2, which is consistent with classification as an ultra-low-porosity and ultra-low-permeability reservoir. The Chang 9 sandstone is composed of feldspar sandstone and lithic feldspar sandstone. The average content of quartz is low, at less than 31%, while the average content of feldspar is high, at more than 34%. The average content of rock debris is between 10% and 20%. Therefore, the compositional maturity of the Chang 9 sand body is generally low. The particle size distribution exhibits a positive deviation, indicating that the sediments in the sand body are primarily coarse-grained components. The kurtosis of the particle size–frequency curve is observed to vary from flat to very sharp. The Chang 91 lake is classified as a shore shallow lake with basin subsidence and lake transgression. The Chang 9 period saw the development of the Chang 91 sedimentary facies into a semi-deep lake–deep lake environment. The vertical structural style of the Chang 9 oil layer formation in the basin can be roughly summarized into three basic structural types: the sedimentary structures observed in the area include box-shaped upward thinning, bell-shaped upward thinning and funnel-shaped upward thickening. The delta front area in Chang 9 is notable for its size and the prevalence of underwater distributary channel microfacies. The sand body distribution is stable, with sand layer thicknesses ranging from 15 to 30 m. The evaluation and summary of the sedimentary characteristics of the Chang 9 oil layer formation provide a geological basis for future exploration and development in the study area.

Optimal Modeling of Ni/YSZ Triple Phase Boundary in Solid Oxide Cells Using First-Principles Calculations

Abstract Power generation with renewable energy using solid oxide cells (SOCs) has been widely researched. To solve the existing problems of SOCs, such as degradation and efficiency improvement, it is essential to understand reaction mechanisms on the surface/interface such as triple phase boundary (TPB) composed of catalysts, electrolytes, and gas phases. However, a reliable TPB model has not been uniquely defined to discuss the property. This study focused on the TPB model comprising Ni catalysts, yttria-stabilized zirconia (YSZ) electrolytes, and gas phases, and aimed to theoretically identify a reliable TPB model by using density functional theory calculations. The stable structure of YSZ surface models was first identified considering various oxygen vacancy positions, yttrium atom arrangements, yttria concentration, and YSZ surfaces. Thereafter, a reliable Ni/YSZ interface model was discussed by evaluating various Ni structure types, Ni interfaces in contact with the YSZ surface, and interface positions. As a result, we have proposed a more reliable YSZ surface structure than previous reports and reasonable Ni/YSZ interface models considering the computational cost to discuss the properties of TPB. These findings will contribute to the improved design of SOCs as high-performance energy conversion systems for sustainable energy storage.

Mechanical Properties of Selective Laser Melting‐Processed Multihierarchical Lattice Structure Based on Body‐Centered‐Cubic Unit Cell

Herein, three types of multihierarchical lattice structures (MHLSs) with different configurations are designed based on the body‐centered‐cubic (BCC) unit cell. The designed lattice structures are fabricated using Ti‐6Al‐4 V powder as feedstock material through selective laser melting (SLM) technology. The microstructure and surface morphology of the SLM‐formed samples are observed by optical microscopy and scanning electron microscopy, respectively. Theoretical calculation and quasistatic compression experiment are carried out to investigate their mechanical properties. The result shows that the size error of slave cell with small strut diameters is greater than that of master cell with larger strut diameters. All MHLSs exhibit superior mechanical properties compared to the BCC lattice structure. Moreover, the specific elastic modulus and specific yield strength of MHLSs with the best mechanical properties are 70.1% and 51.0% higher than that of BCC lattice structure, respectively. Meanwhile, theoretical calculation results of the elastic modulus and yield strength are consistent with the results of quasi‐static compression testing. The fracture morphology analysis indicates that the struts of the MHLSs samples exhibit a mixed brittle–plastic fracture mode, while the nodes exhibit a plastic fracture mode.

Mild renal dysfunction causes aggravated cardiac damage in type 2 diabetic patients: a comprehensive echocardiography study.

We sought to detect left ventricular (LV) adverse alterations in structure and function in type 2 diabetes mellitus (T2DM) patients with or without mild renal dysfunction (MRD) using comprehensive echocardiography techniques and to explore the independent risk factors for LV remodeling (LVR) and dysfunction in these patients. The study included 82 T2DM patients with normal LV ejection fraction (presence (n = 42)/absence (n = 40) of MRD). Age- and gender-matched controls (n = 40) were also recruited. LV structure and function were evaluated using conventional echocardiography and three-dimensional speckle tracking echocardiography (3DSTE). Global longitudinal strain (GLS), global circumferential strain (GCS), global area strain (GAS), and global radial strain (GRS) were all measured using 3DSTE. Compared with the controls with absolute advantage of LV normal geometry, LVR was more frequently present in the two T2DM groups, with the largest proportion in those with T2DM and MRD (P < 0.001). Fasting plasma glucose (FPG) and MRD were both significant risk factors for LVR in T2DM patients. The detection rates of LV diastolic dysfunction and subclinical systolic dysfunction were significantly higher in the T2DM groups than in the controls (P = 0.000). Moreover, the two case groups also showed significantly lower strain values in multiple directions than the controls (all P < 0.05). FPG was significantly associated with LV diastolic dysfunction, whereas FPG and MRD were both significantly associated with subclinical LV systolic dysfunction in T2DM patients. The combined use of conventional echocardiography and 3DSTE allowed the timely detection of early cardiac damage in T2DM patients with or without MRD.

Detection method for structural defects of U-shaped hanging ring for power fittings based on magnetic leakage principle

Abstract The U-shaped hanging ring of electric power fittings is usually installed outdoors and operates in harsh environments. Under the combined effect of the weight of the conductor and wind load, the bending part at the bottom of the U-shaped hanging ring often experiences wear and cracks due to friction contact, which can easily lead to accidents such as the detachment of transmission lines. Traditional methods for detecting corrosion defects in ferromagnetic materials, such as ultrasonic testing, eddy current testing, and manual testing, are affected by environmental factors, have a shallow measurement depth, and are difficult to quantify. In order to solve the above problems, this paper proposes a measurement method for detecting corrosion defects in the U-shaped hanging ring of electric power fittings based on the principle of magnetic leakage. The magnetic leakage signal characteristics of U-shaped hanging ring defects under different excitation structural parameters and different corrosion types are analyzed. The method of arranging magnetic leakage signal measurement points is studied. The detection of defect parameters is achieved based on the characteristic quantity of the magnetic leakage signal under different corrosion conditions. Finally, the method is analyzed and verified through examples. The results show that this method can achieve quantitative detection of defect parameters in the U-shaped hanging ring under uniform corrosion and crack corrosion, and has the advantages of high measurement accuracy and small error. The research results of this paper can provide a scientific theoretical basis for the inspection and replacement of transmission line fittings in engineering, which is of great engineering significance for ensuring the safe and stable operation of the power grid.&amp;#xD;

Anomalous Hall effect and magnetic transition in the kagome material YbMn6Sn6

We investigate the magnetic and transport properties of a kagome magnet YbMn6Sn6. We have grown YbMn6Sn6 single crystals having a HfFe6Ge6 type structure with ordered Yb and Sn atoms, which is different from the distorted structure previously reported. The single crystal undergoes a ferromagnetic phase transition around 300 K and a ferrimagnetic transition at approximately 30 K, and the magnetic transition at low temperature may be correlated to the ordered Yb sublattice. Negative magnetoresistance has been observed at high temperatures, while the positive magnetoresistance appears at 5 K when the current is oriented out of kagome plane. We observe a large anisotropic anomalous Hall effect with the intrinsic Hall contribution of 141 Ω−1cm−1 for σzxint and 32 Ω−1cm−1 for σxyint , respectively. These values are similar to those in YMn6Sn6 with the same anisotropy. The magnetic transition and anomalous Hall behavior in YbMn6Sn6 highlights the influence of the ordered Yb atoms and rare earth elements on its magnetic and transport properties.

On the issue of the manufacture of ceramic structures in orthopedic dentistry

The article presents a review of ceramic materials used in modern orthopedic dentistry. Currently, the main types of orthopedic structures containing dental porcelain are metal-ceramic, metal-free ceramic crowns, as well as prostheses made using pressed ceramic technology, in particular veneers. All types of prostheses produced using dental porcelain have a common manufacturing technology, which consists in the sequential application of ceramic layers with their subsequent firing. Moreover, for each group of teeth, there are additional masses for firing, for example, masses of the cutting edge, masses simulating various effects (for example, blue, yellow and other shades, imitation of tooth growth lines). These masses are created in order to give future crowns the most natural and aesthetic appearance. All structural components (layers) of ceramics used in the manufacture of ceramic prostheses have a similar chemical composition. The raw material is feldspar glass with inclusions of crystalline quartz. Depending on the conditions of the reactions, the composition of mixtures can be varied and compounds with desired properties can be obtained using the phase analysis method, which will expand the range of domestic ceramic materials produced, which are currently quite scarce. This is especially relevant in modern conditions of import substitution.

Cost optimization of tall buildings having tube composite columns using social spider algorithm

SummaryThis study aims to develop an algorithmic approach to obtain optimum designs for tall buildings having composite columns and investigate the material cost advantages of these buildings over steel structures. The social spider optimization (SSO) algorithm, a new meta‐heuristic optimization method that has shown promising results in optimizing frame structures, was used to obtain the optimum designs. Concrete‐filled steel tube sections were chosen for composite columns. To define the optimization problem, we considered the material cost of the structure as the objective function, the size of columns (strength, deflection, drift, and geometric limitations) as the constraint functions, and ready steel sections as the design variables. We tested eight different frame structures of varying heights and irregularities to analyze how cost varied according to these parameters. Our results demonstrate that composite columns are a more cost‐effective option than steel structures, even for buildings that are not considered high rises. We found that the difference in cost between the two types of structures increases with building height and irregularity. Additionally, our optimization algorithm was unable to find feasible designs for steel structures taller than 180 m using ready steel profiles.

Enhancing oxygen evolution reaction performance of Ruddlesden–Popper perovskite oxide through heteroatom incorporation

Prior studies have demonstrated that Ruddlesden–Popper (RP) type perovskite oxides exhibit promising electrocatalytic properties for oxygen evolution reaction (OER). However, the limited electrocatalytic activity has impeded their widespread utilization. The incorporation of heteroatoms into the Ruddlesden–Popper type structure has been identified as an effective strategy to enhance the electrocatalytic performance. This research presents the systematic design and synthesis of RP type perovskite oxide LaSrFeO4 (LSFO), followed by the optimization of electrocatalytic activity through Ni substitution at the Fe site of SLFO to create LaSrFe1-xNixO4 (LSFNO-x, x = 0.2, 0.4, and 0.5). Therein, the LSFNO-0.4 sample achieved a current density of 10 mA·cm−2 with an overpotential of only 340 mV. Additionally, it displayed exceptional stability over 120 h in a 1.0 M KOH solution. Both experimental and theoretical studies suggest that the addition of Ni cation increases the Fe − O covalency, and impacts the morphology and surface electron density of LSFO. This substitution results in a greater electrochemically active surface area, improved electron transfer, and optimization of hydrogen/water absorption free energy. This study presents a successful approach for enhancing the OER performance of Ruddlesden–Popper LSFO through the deliberate control of Fe − O covalent bonding.

Interface Nuclei in the Y-Ag-Zn System: Three Chemical Pressure-Templated Phases with Lamellar Mg2Zn11- and CaPd5+x-Type Domains.

The interface nucleus approach was recently presented as a framework for understanding and predicting the emergence of modular intermetallic phases, i.e., complex structures derived from the assembly of units from simpler parent structures. Here, we present the synthesis and crystal structures of three new modular intermetallics in the Y-Ag-Zn system that support this strategy: YAg2.79Zn2.80 (I), YAg2.44Zn3.17 (II), and YAg2.71Zn2.71 (III). Each of these structures is derived from an intergrowth of slabs of the Mg2Zn11 and CaPd5+x types, with the chief differences being in the thickness and degree of disorder within the CaPd5+x-type domains. The merging of the parent structure domains is facilitated by their sharing a common geometrical unit, a double hexagonal antiprism. The use of this motif as an interface nucleus mirrors its role in another family of structures: an intergrowth series combining the CaCu5 and Laves phase structure types, as in the PuNi3-type phase YNi3. However, there is a key difference between the two series. While in the CaCu5/Laves intergrowths, the interface between the parent structures arises perpendicular to the interface nucleus's unique (hexagonal) axis, in the Mg2Zn11/CaPd5+x-type intergrowths revealed here, the interfaces run parallel to this axis. Using CP analysis of the Mg2Zn11/CaPd5+x-type parent structures, we trace this behavior to the different directions of high-CP compatibility of the interface nuclei in the Mg2Zn11/CaPd5+x and CaCu5/Laves structure type pairs. In this way, the Y(Ag/Zn)5+x phases highlight the role that interface nuclei play in directing the domain morphologies of modular intermetallic phases.

New Phases in the Sc−Mn−Si and Sc−Mn−Al−Si Systems Through Molten Indium Flux Synthesis

AbstractThrough the application of synthesis via molten indium flux, we have been able to expand the ternary Sc−Mn−Si system and the quaternary Sc−Mn−Al−Si system. Specifically, we report on five previously unknown chemical compounds, namely β‐ScMnSi2, Sc4+xMn4Si7–2x, Sc2Mn4Si5, Sc2Mn3Si4, and Sc4Mn2AlSi4. The compounds with the stoichiometries Sc2Mn4Si5, Sc2Mn3Si4, and Sc4Mn2AlSi4 have previously not been reported. We find that these crystallize in the V6Si5, Hf2Ru3Si4, and Ho4Ni2InGe4 structure types, respectively. For the ternary compounds with the stoichiometries of ScMnSi2 and Sc4+xMn4Si7–2x, we find clearly deviating structural solutions compared to earlier reports. β‐ScMnSi2 is found to crystallize in the monoclinic crystal system isostructural to a supercell of the MnTiSi2 structure and clearly deviating from the known orthorhombic α‐polymorph. The compound Sc4+xMn4Si7–2x is structurally very similar to Sc4Mn4Si7, but exhibits the P4/nmm space group instead of I4/mmm, and is related to the Zr4Co4Ge7 structure. Disorder between Si and Sc sites leads to the off‐stoichiometric composition, for which we found x=0.287(5).