bluuebunny/crossref_metadata_2025_split huggingface dataset:
Technical innovation and research of autoclaved aerated concrete block/panel equipment
Authors: Chen Chadwick , Xu Shunwu , Qi Guoliang , Huo Wenquan 
Published: September 2023

AbstractRecent years with the development of green buildings, the market demand for new building materials is rising, which also comes the high requirements for production technology, equipment durability and product quality. Taking the successful experience from hundred projects, KEDA SUREMAKER upgrades practical functions of AAC core equipment such as the cutting section and packing section to improve working efficiency, productivity, and durability, and make equipment easier to operate and maintain. For the production of high‐quality AAC panel, a new solution of vertical cake cutting—green cake separation—flat cake autoclaving is launched. As for the demands of mass AAC block production, a new three‐layer efficiency white cake separation technology is given. In addition, the production management system of the whole factory has been upgraded to make AAC plant management more efficient.
The bulk density of AAC – Influencing factors and their magnitude
Authors: Haas Martin 
Published: September 2023

AbstractThe bulk density of AAC determines many of its properties like compressive strength, thermal conductivity, sound insulation, and so on. It is described by the solid mass divided by the volume. The volume again is determined by the volume of the slurry in the mixer plus the rising volume. The rising volume is mainly caused by the hydrogen generation of the aluminum reaction. In practice, the rising volume is controlled by dosing of the aluminum, based on experience. This article shows that the rising volume cannot be calculated resp. controlled by the aluminum reaction only. Other influence parameters like casting temperature, final temperature and air pressure must be considered. The magnitude of this influence parameters is described, and some practical consequences are shown.
Polish approach to the development of AAC properties and applications
Authors: Zapotoczna–Sytek Genowefa , Małolepszy Jan , Soboń Mieczysław 
Published: September 2023

AbstractOver 70 years of AAC production in Poland prompts us to present our path from the beginning of its manufacturing in 1951 to the high quality of today. To launch AAC production in Poland was a significant decision that helped rebuild the country after World War II. Today AAC is one of the most popular wall‐building materials in Poland (about 40%), and housing development, on a large scale, would be practically impossible without it. We will discuss the current steps we take in search of raw materials optimal for AAC production, both natural (primary) and recyclable (or “secondary”), like power‐generation, chemical, or other industry by‐products. We will also discuss changes to product assortment: from small‐size to medium and large‐size reinforced elements with full factory finish, as well as the state of the art in this area. We will look at technical progress in production processes. Given the AAC properties and our technology achievements, we believe that further AAC development will primarily concern phase composition, the microstructure and pore structure of aerated concrete. In our works, we have addressed those aspects and taken efforts to design AAC composition with carbon footprint in mind. We also carried out an extensive study on the durability of AAC.
Analysis of thermal solutions in challenging spots of masonry constructions
Authors: Walczak Paweł , Rybarczyk Tomasz 
Published: September 2023

AbstractAutoclaved aerated concrete (AAC) is a construction material with very good thermal properties. In many countries, the majority of masonry structures are developed using a single wall from low‐density AAC. In some countries, like Poland, the most popular solution is an AAC construction wall with covering insulation material. In the house construction process, several challenging spots can be observed where thermal bridges can develop. One of them will be the place of installation of external window roller blinds on a reinforced concrete lintel or an aerated concrete lintel. In fact, there are several solutions to this problem, but there is no clear answer in the literature about which of those will be optimal in terms of reducing the loss of thermal energy, the cost of which is growing year by year. The research program includes tests of the thermal conductivity of a wall unit built of AAC of various density classes, with the most popular thermal insulation materials available on the market, such as: EPS polystyrene, XPS polystyrene, or aluminum mats.
Evaluation of the compressive strength of autoclaved aerated concrete in existing masonry
Authors: Drobiec Łukasz , Jasiński Radosław , Mazur Wojciech 
Published: September 2023

AbstractSclerometric method, commonly used in reinforced concrete structures, have also found application in masonry structures, mainly in the diagnosis of brick masonry walls or testing mortar in joints. This article presents a proposal for determining the compressive strength of autoclaved aerated concrete masonry elements with the use of the Schmidt OS‐120 PT pendulum hammer. The test was carried out on masonry elements with a nominal density class of 400 and 600. Additional tests were also carried out on samples with different levels of humidity, in order to consider the influence of humidity on the change in rebound number and changes in compressive strength.
Increasing the flexibility in aluminum paste dosing system: A comparison between shift pre‐mixing system and batch pre‐mixing system designs
Authors: Aldarrat Hatem , Drosten Gerrit , Bikbulatov Marat 
Published: September 2023

AbstractThe production of autoclaved aerated concrete (AAC) is a multiple industrial process that depends on the quality of the used raw materials, mixing ratios as well as on the consistency between the chemical and mechanical performance of the mixing unit in a mixing tower. Optimizing the mixing process, ratios and many other overlapping elements are important factors for its ideal design to ensure reducing production costs and reducing waste of the basic raw materials, that could be happened due to the inflexibility of the used dosing system design. Since the aluminum paste is one of the most important basic raw materials for the manufacture of autoclaved aerated concrete with a low participation rate in the mixture of about 0.1% (e.g., AAC ‐G4 type), however, in terms of production costs, it constitutes a part of not less than 10% of the total raw materials cost per cubic meter of autoclaved aerated concrete (e.g., AAC‐G4 type), according to several real studies in several factories. Through this research, we present a comparison between two aluminum paste dosing system designs already implemented in several AAC factories: (1) shift pre‐mixing and weighting model and system‐ ASMD, (2) Batch pre‐mixing and weighting Model‐ ABMD. This research will illustrate the differences between the two systems in terms of technical and financial aspects based on the reality of practical experience.
Investigation of effective replacement of sand by waste perlite in AAC production
Authors: Černý Vít , Mészárosová Lenka , Drochytka Rostislav , Melichar Jindřich 
Published: September 2023

AbstractAerated concrete is a lightweight building material with excellent thermal and technical properties, relative to strength, excellent workability, and is economically advantageous. The basic composition of raw materials includes lime, cement, silica sand, and aluminum powder. Currently, the usability of secondary raw materials is being investigated in many construction sectors. The usability of secondary raw materials becomes a necessity from an ecological and economic point of view. The elimination of CO2 emissions is currently a major global issue. Secondary raw materials used in the construction industry are most often waste materials produced during the combustion of solid substances. These substances are often accumulated in landfills, which have a negative impact on the surrounding environment. It is necessary to constantly look for new ways of using these waste materials not only in the construction industry. The use of these raw materials reduces the price of the final product. It is advantageous if it also brings about a positive change in the properties of aerated concrete. The article deals with the possibility of replacing part or all of the sand content in the recipe of autoclaved aerated concrete with waste perlite. As part of the experimental verification, the influence of waste perlite filler on physical‐mechanical properties (e.g., bulk density, strength) and changes in microstructure is investigated. Primary sand is replaced by perlite in the amount of 10%, 30%, 50%, and 100% by volume in the experiments. The formation of porous structure, its characteristics, and mineralogical composition, in particular the formation of tobermorite, is also evaluated. The study has brought an interesting finding. The results show that the maximum beneficial amount of waste perlite is 30%. Up to this limit, waste perlite has a positive effect on the even distribution of pores in the matrix, with a zero‐phase content of more than 65%. The compressive strength of the samples with waste perlite increases by up to 22% of the values of the compressive strength of the reference sample.
Recarbonation matters—CO2 absorption of AAC during its use phase
Authors: Walther Hartmut B. 
Published: September 2023

AbstractRebounding of CO2 during service life and recycling in building materials reduces the CO2 content of the atmosphere. The CO2 was formerly released from limestone through deacidification during the production of cement and quicklime. Binder‐bound building materials later reabsorb this CO2 again. This process is called recarbonation. In contrast to concrete, detailed knowledge about the CO2 cycles of autoclaved aerated concrete (AAC) is missing. Standards concerning adequate sampling and measurement methods as well as suitable calculation methods are currently under development.According to the valid EN 15804:2012+A2:2019, life cycle assessments and environmental product declarations (EPDs) concern the entire product life cycle and thus also the CO2 reabsorption by building materials. For AAC, this amount can be calculated from the raw material input. The reduction bases on the active CaO contained in the AAC, is absolute and related to the binder mass used. Thus, it can be applied comprehensively and without the influence of the used database system of the background data in EPDs.Unfortunately, the amount of originally active CaO cannot be measured directly in AAC samples. As a first approximation, it was obvious to assume that all chemically determinable CaO in AAC was formerly active. However, this method underestimates the degree of recarbonation because the raw materials also contain non‐reactive CaO, for example, in the form of calcium silicates. Nevertheless, all diagrams concerning recarbonation of AAC are based on this assumption and the values are too low.In the presentation, we will introduce a new method to determine the degree of recarbonation of AAC—forced carbonation. Forced carbonation is carried out under defined temperature, humidity, and CO2 conditions in a climate chamber. The measurement is bases on the detection of CO2 in the sample and considers the proportion of non‐reactive CaO and thus leads to realistic degrees of recarbonation.
Investigation of seismic performance of indoor AAC infill walls with flat‐truss bed‐joint reinforcement
Authors: Halici Omer Faruk , Demir Ugur , Zabbar Yassin , Ilki Alper 
Published: September 2023

AbstractIntroductionAutoclaved Aerated Concrete (AAC) is a lightweight and energy‐efficient material which makes it one of the most convenient materials to be used in infill walls. Accordingly, AAC walls are becoming more and more favored infill systems in earthquake‐prone regions. Although the infills are not considered primary components in seismic design, they are highly susceptible to be damaged under seismic actions in in‐plane (IP) and out‐of‐plane (OOP) directions.ObjectivePast post‐earthquake site surveys indicated that the failure of infill walls may result in severe casualties, injuries, and economic losses. In addition, damage to infills may hinder the functionality of critical buildings, which are expected to be in service after earthquakes. The application of horizontal bed‐joint reinforcement between infill courses is one of the promising solutions to increase the seismic resilience of infill walls.MethodologyThis paper presents the experimental performance investigation of AAC infill walls with flat‐truss bed‐joint reinforcement being subjected to lateral loading in IP and OOP directions. The specimens represent relatively thin infills with a thickness of 150 mm, which are generally used in indoor environments. To consider the seismic actions in the IP direction, two full‐scale infill wall specimens (one unreinforced reference and one with flat‐truss reinforcement) built in reinforced concrete frames were first tested under reversed cyclic IP displacement reversals and then tested under the cyclic OOP displacements.ConclusionsThe results revealed that the use of flat‐truss reinforcement enhanced the OOP strength, ultimate displacement, and energy dissipation capacity of infill walls that have been subjected to cyclic IP displacements previously.
The modern Autoclaved Aerated Concrete (AAC) plant of today for a sustainable tomorrow
Authors: Tavenier Corniels , Beier Ralf , van Boggelen Koen 
Published: September 2023

AbstractAAC, already produced since the 1920's, has been subject to continuous innovation and evolution over the history of its product life. The same applies to the AAC production process. Recently, the need for innovation has become more apparent than ever, driven by a serious energy crisis in Europe, combined with an increasing shortage of available labor and an increasing awareness of workers safety. Since the 70's, Aircrete Europe founding roots were highly involved in driving innovation in the AAC industry, with an emphasis on AAC panels. In every project designed by Aircrete top‐class innovation and the highest level of sustainability are always a top priority and are considered already from the very early design phase. As a result of this, Aircrete factories can be operated with the highest level of automation and energy‐saving initiatives to ensure higher operator safety, larger operating efficiency, and a minimized carbon footprint. This paper outlines how decades of experience from being involved in its own AAC operations result in how Aircrete can design a factory that is not only able to meet today's highest safety, regulatory, and environmental standards but is also future‐proof for the anticipated global trends in the industrial manufacturing and construction markets.
Short‐term length change measurements and sorption isotherms for AAC compared to OPC
Authors: Wahab Mirco , Waida Sandra , Bier Thomas A. 
Published: September 2023

AbstractThe interaction of adsorbed water with the microstructure of cementitious materials leads to effects on macroscopic properties. However, precise quantitative correlation of adsorbed water with short‐term changes in macroscopic properties, such as dimensional changes, remains a challenge. We compare recent results from precise dual‐microscope‐based short‐term length change measurements and discuss differences in length‐change isotherms and adsorption isotherms arising from various cement types. Water vapor adsorption happens already at very low humidity in the interlayer space of the C‐S‐H gel. Adsorption and desorption on cement surfaces due to changing relative humidity induces strong forces in the cement gel, leading to detectable changes in dimensional stability for the hardened material. A significant hysteresis in the water desorption isotherm is often accompanied by hysteresis in dimensional change as well. For precise length change measurements, an optical method for tracking surface patterns on thin cement slices was applied. Short‐term length change results are compared to corresponding water vapor sorption isotherms and pore size measurements. Hypotheses and conclusions regarding microstructural changes and shrinkage mechanisms are discussed in order to understand the experimental data.
EAACA net zero roadmap for autoclaved aerated concrete
Authors: Turski Robert , Kreft Oliver , Fudge Clifford , Walczak Paweł 
Published: September 2023

AbstractThis roadmap sets out a pathway for Autoclaved Aerated Concrete (AAC) products to reach net‐zero emissions by 2050 with the potential to become carbon negative, thereby absorbing more carbon dioxide from the atmosphere than they produce. The roadmap aligns the European Autoclaved Aerated Concrete Association (EAACA) and its members with the objectives of the Paris Agreement to limit global warming to 1.5°C and supports policies to decarbonize Europe's buildings and construction sectors. AAC is a lightweight, yet strong and durable building material that offers ultra‐efficient thermal insulation, optimum fire protection, and a high load‐bearing capacity. With its net‐zero roadmap and the potential to become carbon negative, AAC has a role to play as a building material in helping to reduce the life‐cycle emissions of Europe's buildings. The roadmap sets out the main levers that must be applied to achieve this. We have drawn these from known technologies and have based our net‐zero target on a life‐cycle analysis provided by an independently verified Environmental Product Declaration. As the majority of CO2e emissions come not from the manufacture of AAC itself, but from the manufacture of two key raw materials—cement and lime—the roadmap draws on the decarburization pathways published by global and European cement and lime industry associations. The building and construction sectors account for a significant share of Europe's greenhouse gas emissions that contribute to climate change. Through this roadmap, the EAACA and its members are committed to achieving net‐zero emissions in AAC products by 2050 and supporting the development of a climate‐neutral Europe.
2D Covalent Organic Frameworks with Kagome Lattice: Synthesis and Applications
Authors: Tu Jing , Song Wen , Chen Bo , Li Yusen , Chen Long 
Published: September 2023

Abstract2D covalent organic frameworks with Kagome (kgm) topology are a promising class of crystalline frameworks that possess both triangular and hexagonal pores. These dual‐pore structures enable kgm COFs to exhibit unique advantages in selective separation, mass transfer, and targeted drug release. However, the synthesis of 2D kgm COFs has been hindered by the reliance on empirical methods. This review systematically summarizes the conventional macrocycle‐to‐framework strategy, typical [4+2] co‐polymerization synthetic strategy, and bifunctional molecules self‐condensation approach for constructing 2D kgm COFs. Factors influencing the formation of kgm lattice are surveyed, such as monomer type, solvent polarity, substrate concentration, etc., and highlight the representative examples on targeted synthesis. Additionally, applications of 2D kgm COFs and relationships between structure and performances are summarized. Finally, key fundamental perspectives are proposed to accelerate the further development of this intriguing material.
The predictive value of abnormal electrocardiogram for patent foramen ovale: A retrospective study
Authors: Jin Peng , Jiao Piqi , Feng Juan , Shi Liang , Ma Ling 
Published: September 2023

AbstractBackground and HypothesisThe objective of this study was to identify the characteristics of electrocardiogram (ECG) in adult patients with patent foramen ovale (PFO) and to analyze the predictive value of the characteristics of ECG for PFO in adult patients.MethodsRetrospectively, 267 patients who had undergone ECG, transthoracic echocardiography (TTE), transesophageal echocardiography (TEE) with agitated saline contrast echocardiography in our hospital, were recruited continuously from January 2021 to March 2023. Electrocardiographs were analyzed to investigate the presence of right bundle branch block (RBBB) and crochetage R wave.ResultsThe ratio of crochetage R wave in inferior leads in patients with PFO was 45.3% and 21.2% without PFO. There were 17 (6.4%) patients with coexistence of crochetage R wave and RBBB, including 13 (6.5%) patients with PFO and four (6.1%) patients without PFO. The accuracies of TTE, crochetage R wave, and RBBB were 0.637, 0.535, and 0.314, respectively. A combination of crochetage R wave and RBBB demonstrated a sensitivity of 0.507 and a specificity of 0.758. When TTE, crochetage R wave, and RBBB were combined, the accuracy, sensitivity, specificity, positive predictive value, and negative predictive value were 0.712, 0.801, 0.439, 0.813, and 0.420, respectively. Logistic regression analysis revealed a correlation between PFO and the presence of crochetage R wave (odds ratio [OR]: 3.073, 95% confidence interval [CI]: 1.601–5.899, p < 0.001), and also a combination between crochetage R wave and RBBB (OR: 3.220, 95% CI: 1.720–6.028, p < 0.001).ConclusionsCrochetage R wave in ECG was associated with PFO. Crochetage R wave, especially combined with RBBB and TTE, may be helpful in the early detection of patients with PFO.
Phylogenetic and biogeographic history of brook lampreys (Lampetra: Petromyzontidae) in the river basins of the Adriatic Sea based on DNA barcode data
Authors: Rüber Lukas , Gandolfi Andrea , Foresti Danilo , Paltrinieri Luca , Splendiani Andrea , Seehausen Ole 
Published: September 2023

AbstractThe Adriatic brook lamprey, Lampetra zanandreai Vladykov 1955, was described from northeastern Italy. Its distribution is thought to include left tributaries of the River Po and the river basins of the Adriatic Sea from the River Po to the River Isonzo/Soča in Italy, Switzerland and Slovenia. It also shows a geographically isolated distribution in the Potenza River on the Adriatic slope in Central Italy. Lampetra from the Neretva River system in Croatia and Bosnia and Herzegovina and the Morača River system in Montenegro that were previously identified as L. zanandreai were recently described as a new species Lampetra soljani Tutman, Freyhof, Dulčić, Glamuzina & Geiger 2017 based on morphological data and a genetic distance between the two species of roughly 2.5% in the DNA barcoding gene cytochrome oxidase I (COI). Since DNA barcodes for L. zanandreai are only available for one population from the upper Po River in northwestern Italy, we generated additional COI nucleotide sequence data of this species from Switzerland, northeastern and central Italy comprising near topotypic material and obtained GenBank sequences of the species from Slovenia to better assess the evolutionary history of the two brook lamprey species in the river basins of the Adriatic Sea. Our data show a low sequence divergence of <1% between L. zanandreai from Switzerland, northeastern and central Italy and Slovenia and the Balkan species L. soljani. However, members of the population previously identified as ‘L. zanandreai’ from northwest Italy are genetically highly divergent from those of L. zanandreai and likely belong to an undescribed species, L. sp. ‘upper Po’. The presence of a unique and highly divergent brook lamprey lineage in the upper Po River suggests that L. zanandreai and Lampetra sp. ‘upper Po’ may have evolved in separate paleo drainages during the formation of the modern Po Valley subsequent to marine inundations in the Pliocene.