bluuebunny/crossref_metadata_2025 huggingface dataset:
Effects of additive NH3 with citric acid in the precursor and controlling the deposited thickness for growing molybdenum oxide crystals and nanorods
Authors: Hirose Yukiko , Sugahara Tohru , Nakamura Jun-ichi , Harada Nobuyuki , Suganuma Katsuaki
Published: October 2020

In recent years, researchers have successfully formed fine single crystal-like α-MoO3 nanorods on substrate using metal–organic decomposition method. In this study, the researchers found that the NH3 additive effects with citric acid in the precursor for growth the nanorods.
Practical synthesis of immucillins BCX-1777 and BCX-4430
Authors: Zhang Minjie , Xue Fei , Ou Jingdan , Huang Yuan , Lu Fei , Zhou Bingqing , Zheng Zhibing , Liu Xiao-Yu , Zhong Wu , Qin Yong
Published: October 2020

A practical synthesis of the immucillins BCX-1777 and BCX-4430 has been described.
Recent advances in the development of histone deacylase SIRT2 inhibitors
Authors: Yang Wenyu , Chen Wei , Su Huilin , Li Rong , Song Chen , Wang Zhouyu , Yang Lingling
Published: October 2020

This review presents a systematic summarization of nine chemotypes of small-molecule SIRT2 inhibitors, which will be useful for future efforts to develop new inhibitors targeting SIRT2 and associated target proteins.
Amino group dependent sensing properties of metal–organic frameworks: selective turn-on fluorescence detection of lysine and arginine
Authors: Dong Jing , Zhang Xiu-Du , Xie Xia-Fei , Guo Fan , Sun Wei-Yin
Published: October 2020

The amino group of UiO-66-NH2 was demonstrated to play an important role in selective fluorescence turn-on sensing of lysine and arginine.
Single-site binding of pyrene to poly(ester-imide)s incorporating long spacer-units: prediction of NMR resonance-patterns from a fractal model
Authors: Knappert Marcus , Jin Tianqi , Midgley Scott D. , Wu Guanglu , Scherman Oren A. , Grau-Crespo Ricardo , Colquhoun Howard M.
Published: October 2020

Nine 1H NMR resonances assignable to specific copoly(ester-imide) sequences identified from a fractal model result from 1 : 1 supramolecular binding of pyrene to NDI residues.
Subcellular localised small molecule fluorescent probes to image mobile Zn2+
Authors: Fang Le , Watkinson Michael
Published: October 2020

A number of recently developed subcellular localised small molecule fluorescent probes to image mobile Zn2+are reviewed in this perspective.
Rhenium versus cadmium: an alternative structure for a thermally stable cadmium carbonyl compound
Authors: Amemiya Erika , Loo Aaron , Shlian Daniel G. , Parkin Gerard
Published: October 2020

The previously reported novel cadmium carbonyl compound, [Cd(CO)3(C6H3Cl)]4, is better formulated as the rhenium compound, [Re(CO)3(C4N2H3S)]4.
Visible-light triggered templated ligation on surface using furan-modified PNAs
Authors: Manicardi Alex , Cadoni Enrico , Madder Annemieke
Published: October 2020

Pinpoint production of singlet oxygen was exploited for a self-contained light-triggered activation of a pro-reactive furan moiety, allowing selective and templated surface modification by recognition of short 22mer oligonucleotides.
Contributions from microstructural changes to the rheological behavior of casein dispersions during drying
Authors: Sruthi Lalitha , Srivastava Vishal , Schmidt Lars E. , Deshpande Abhijit P. , Varughese Susy
Published: October 2020

Rheology and microstructure of casein dispersions undergoing drying are investigated. Drying alters conformational composition of secondary structures of the protein (α-helix, β-sheets, turns and random) and hence the packing behavior of molecular assemblies of casein.
Cholesterol sequestration by xenon nano bubbles leads to lipid raft destabilization
Authors: Reyes-Figueroa A. D. , Karttunen Mikko , Ruiz-Suárez J. C.
Published: October 2020

Combined coarse-grained (CG) and atomistic molecular dynamics (MD) simulations were performed to study the interactions of xenon with model lipid rafts consisting of DPPC, DLPC and Chol.
Computational design of a metal-based frustrated Lewis pair on defective UiO-66 for CO2hydrogenation to methanol
Authors: Yang Kuiwei , Jiang Jianwen
Published: October 2020

An active FLP structure is computationally proposed through defect-engineering of UiO-66 for CO2hydrogenation to CH3OH.
Mechanically robust, exceptionally recyclable and shape memory cross-linked network based on reversible dynamic urea bonds
Authors: Jiang Liang , Lei Yuan , Xiao Yao , Fu Xiaowei , Kong Weibo , Wang Yuechuan , Lei Jingxin
Published: October 2020

Using dynamic covalent bonds to construct dynamic polymer materials has been attracting interest to thrive the smart, responsive and adaptive polymeric materials.
Long-term and label-free monitoring for osteogenic differentiation of mesenchymal stem cells using force sensor and impedance measurement
Authors: Zhang Zhizhong , Zheng Tianyang , Zhu Rong
Published: October 2020

Label-free and continuous multimodal measurements of cell traction force and cell impedance for studying osteogenic differentiation of stem cells.
Extension of a PID control theory to Lie groups applied to synchronising satellites and drones
Authors: Fiori Simone , Cervigni Italo , Ippoliti Mattia , Menotta Claudio
Published: October 2020

The authors tackle time synchronisation of two (possibly non‐identical) second‐order dynamical systems whose state space possess the structure of a Lie group. Synchronisation is treated as a non‐linear control problem on Lie groups. They present a control theory inspired by the proportional–integral–derivative (PID) regulation principle. The resulting L‐PID control scheme is applied to sync the rotational component of motions in physical systems. A model‐dependent version of the L‐PID, equipped with a dynamics‐cancelling component, is theoretically proven to converge to zero control error by a Lyapunov stability analysis. Furthermore, they present Lie‐group‐tailored numerical techniques to implement the devised PID regulation theory and test such numerical schemes on two dynamical systems, namely, a gyrostat satellite and a quadrotor drone. As a further extension, they present an empirical translational synchronisation algorithm for two drones based on a pair of concurring L‐PID and projected‐PID controllers.
Comparison of the Ocular Trauma Score and Pediatric Ocular Trauma Score as Two Prognostic Models in Pediatric Open Globe Injuries
Authors: Pahor Dusica , Gracner Tomaz
Published: October 2020

Aim To compare the ocular trauma score (OTS) and the pediatric ocular trauma score (POTS) as prognostic models of visual outcome after open globe injury in children during a period of 19 years.

Patients and Methods A retrospective study of 36 open globe injuries in 36 patients younger than 18 years was conducted from January 2000 to January 2019. For each case, OTS and POTS points were calculated.

Results Significant differences were observed in our patients using the two models regarding categories 1 to 4. One third of the cases were in categories 1 and 2 using the OTS model, and nearly 60% using the POTS model. Nearly 60% of our patients were in categories 3 and 4 using the OTS model and 30.6% using the POTS model. In category 5, no difference was observed between the two models. The comparison of distribution of the percentage of final visual acuity between OTS and POTS model in each category revealed a significant difference in category 1 in final visual acuity 20/40 or more (25 vs. 50%) as well as in final visual acuity 20/20 (0 vs. 30%). In category 2, final visual acuity was not significantly different in 20/40 or more between the two models; however, there was a significant difference in final visual acuity 20/20 – 12.5% in the OTS model and 45.5% in the POTS model. In category 3, significant differences were revealed between the two models. Using the OTS model, final visual acuity 20/40 or more was observed in more than 60% and using POTS model in 100%; final visual acuity 20/20 was observed in 36.3% using OTS model and in 50% using POTS model. In category 4 and 5, no differences were observed between OTS and POTS models.

Conclusion Our study did not confirm the benefit of POTS. The distribution of our cases among OTS categories demonstrated a significant difference between the two models with more cases distributed in lower categories in POTS group. In the POTS group, the prognosis for final visual acuity was significantly better in the first three categories than in the OTS group, probably as a result of a lower calculation for POTS points. In our opinion, the OTS model is easier to use, has a higher prognostic accuracy, and should be further used in counselling of paediatric cases.
Routine ileal intubation in colonoscopy does not increase the polyp detection rate: a retrospective study
Authors: Wang Weiyi , Chen Ke , Xu Ying , Zhou Yufen , Chen Ping
Published: October 2020

Colonoscopy is effective in the prevention and screening of colorectal cancer. Whether terminal ileal (TI) intubation is required during conventional colonoscopy and whether it offers clinical benefits with respect to polyp detection rate (PDR) remain unclear. This retrospective study included patients who underwent colonoscopy at our hospital between July 1, 2018 and April 20, 2019. The positive findings and time for TI intubation were recorded. Univariate and multivariate analyses were performed to identify factors associated with PDR. There were 1675 patients with cecal intubation colonoscopy, including 994 (59 %) with TI intubation and 8 (1 %) with intestinal disease. The mean time for TI intubation was 40 seconds (3–338), and the mean time from cecal intubation to arrival at the deep part of TI mucosa was 24 seconds (2–118). The overall PDR was 27 %. On multivariable analysis, age > 50 years [95 % confidence interval (CI) 2.837–4.590], male sex (95 %CI, 0.406–0.649), presence of symptoms (abdominal symptoms vs. asymptomatic, 95 % CI, 1.146–2.468; stool changes vs. asymptomatic, 95 % CI, 1.070–1.834), and non-TI intubation (95 % CI, 1.040–1.648) were independent predictors of higher PDR. Trend analysis indicated decreasing trend of PDR among non-TI intubation group, 0–5 cm TI intubation group, and > 5 cm TI intubation group (30 % vs. 27 % vs. 24 %, respectively; p < 0.05). TI intubation is necessary to identify small bowel disease among a designated population, but it was not suggested to be routinely performed as part of colonoscopy, owing to limited positive intestinal findings, extra time requirement, and possible PDR worsening.
Sekundärprophylaxe der zerebralen Ischämie
Authors: Ringleb Peter A. , Reiff Tilman
Published: October 2020

Die Sekundärprävention von Hirninfarkt und TIA umfasst neben wichtigen Maßnahmen der Lebensstiländerung zur Risikofaktorenmodifikation verschiedene medikamentöse und interventionelle Verfahren. Durch Behandlung von arterieller Hypertonie und Hyperlipidämie können erneute vaskuläre Ereignisse, Schlaganfall wie Herzinfarkt, verhindert werden. Eine große Bedeutung hat auch die antithrombotische Sekundärprävention durch Thrombozytenaggregationshemmer und orale Antikoagulantien sowie deren Kombination. Bei Vorliegen symptomatischer intra- oder extrakranieller arteriosklerotischer Stenosen können auch gefäßchirurgische oder neuroradiologisch interventionelle Verfahren der Verhinderung weiterer Schlaganfälle dienen.
Improving Transitional Services for Adolescents and Young Adults with Epilepsy and Intellectual Disability
Authors: Schraegle William A. , Young Stephanie R. , Rettig Eman K. , Payne Angie R. , Wilson Janet K. , Wedberg-Sivam Elizabeth A. , Titus Jeffrey B.
Published: October 2020

The transition from pediatric to adult health care systems is challenging for many adolescents with epilepsy and their families, and those challenges are compounded for adolescents with comorbid intellectual disabilities and epilepsy (ID-E). Many traditional transition pathways to adult care are inadequate, as they fail to address important considerations unique to the ID-E population or are absent entirely. Poor organization of care during critical transition periods increases the risks of sudden unexpected death in epilepsy, suboptimal seizure control, inadequate management of comorbidities, and poor psychological and social outcomes. The literature lacks systematic studies on effective transition programs for this population. The present review provides an overview of the main themes important in care transitions for the ID-E population: (1) precise diagnosis and management of seizures; (2) mental health and medical comorbidities affecting care; (3) accessing behavioral, habilitative, legal, financial, and community resources; and (4) caretaker support. We propose a specific framework which includes targeted recommendations of minimum care standards for youth with ID-E transitioning to adult care.
Subdural Empyema by Enterobacter cloacae: Case Report
Authors: Celi Fernando , Saal-Zapata Giancarlo
Published: October 2020

Infections of the central nervous system are a medical emergency, potentially lethal and associated with increased morbidity and mortality. We present the case of a male with risk factors and clinical deterioration, in which the brain computed tomography scan showed a subdural collection following a head injury, which underwent surgical evacuation revealing a subdural empyema. The culture of the subdural collection yielded a positive result to Enterobacter cloacae.
A novel clustering-based filter for impulsive noise reduction in electromagnetic tomography (EMT)
Authors: Chen Ziqi , Salas-Avila Jorge R. , Tao Yang , Yin Wuliang , Zhang Zhijie
Published: October 2020

Demodulation is a crucial step in signal processing for electromagnetic tomography (EMT) systems. Impulse noise appears in EMT, in particular, when excitation current is switched from one coil to another. This is mainly a result of the fact that the discontinuity of current creates voltage spikes due to back electromotive force. This paper proposes a novel clustering-based method for reducing this impulsive noise on the basis of Kalman filter demodulation. The Kalman filter is capable of demodulating the multiplexing signal reclusively, but it introduces dynamic oscillations at the same time. The proposed clustering method is able to successfully separate the signal from the impulse noise and smoothen the dynamic oscillations after demodulation. Simulation and experimental results show that the proposed clustering method can improve the signal-to-noise ratio by more than 20 dB in both the real and imaginary parts of EMT measurements. This technique is also useful in multi-channel coil systems where coil switching is necessary.
Exploration of continuous rheological model for rock under uniaxial compression based on phenomenological damage theory
Authors: Zhou Tianbai , Qin Yueping , Ma Qiufeng
Published: October 2020

The analysis of rock damage under the thermodynamic framework is a research method in continuum damage mechanics. In this method, the coupling relationship between energy and damage is proposed to establish the damage constitutive model of rock from the perspective of phenomenological damage theory. Based on this idea, under the constraint of the law of energy conservation, the evolution process of the damage variable of rock under external load is deduced. Based on the quasi-static damage model, the dynamic damage hypothesis combined with damage driving force theory is proposed to establish a continuous rheological model. The creep processes under uniaxial compression of Shanqing coal and sandstone are simulated, and the long-term strength can be predicted by the proposed model. Finally, the simulation of stress relaxation behavior is also explored in this work. The comparison results show that the proposed model could describe the time-varying behavior of rock under uniaxial compression.
Favipiravir at high doses has potent antiviral activity in SARS-CoV-2−infected hamsters, whereas hydroxychloroquine lacks activity
Authors: Kaptein Suzanne J. F. , Jacobs Sofie , Langendries Lana , Seldeslachts Laura , ter Horst Sebastiaan , Liesenborghs Laurens , Hens Bart , Vergote Valentijn , Heylen Elisabeth , Barthelemy Karine , Maas Elke , De Keyzer Carolien , Bervoets Lindsey , Rymenants Jasper , Van Buyten Tina , Zhang Xin , Abdelnabi Rana , Pang Juanita , Williams Rachel , Thibaut Hendrik Jan , Dallmeier Kai , Boudewijns Robbert , Wouters Jens , Augustijns Patrick , Verougstraete Nick , Cawthorne Christopher , Breuer Judith , Solas Caroline , Weynand Birgit , Annaert Pieter , Spriet Isabel , Vande Velde Greetje , Neyts Johan , Rocha-Pereira Joana , Delang Leen
Published: October 2020

Significance

The previous lack of consensus around the use of hydroxychloroquine for COVID-19 patients underlines the need to thoroughly assess the in vivo efficacy of drugs against SARS-CoV-2. Small animal infection models, such as the hamster model, have a pivotal place herein. We here show in vivo preclinical results with favipiravir which indicate that antiviral efficacy against SARS-CoV-2 might only be achieved with a very high dose. Hydroxychloroquine, on the other hand, completely lacks antiviral activity, thus providing no scientific basis for its further use in COVID-19 patients. With this study on two key antiviral candidates, we establish the baseline for SARS-CoV-2 antiviral treatment, which will allow us to identify superior antiviral candidates in the near future.
Religious tourism and environmental conservation in Lumbini, the birthplace of Lord Buddha, World Heritage Site, Nepal.
Authors: Lafortune-Bernard Anouk , Suwal Rajendra N. , Weise Kai , Coningham Robin A. E.
Published: October 2020

Lumbini is an important pilgrimage site and a tourist attraction in Nepal. This chapter discusses how the Lumbini Master Plan (LMP) integrated the surrounding environment in the site development and the challenges that site managers have faced in implementing this vision and balancing its social, economic, and environmental impacts. With the LMP implementation in its final stages in 2019, the chapter begins by reflecting on the design and its use of the natural environment and landscaping components in its conception of the pilgrim experience. The second section critically reviews the implementation of the plan in comparison with this original design and considers its impact on local dynamics, particularly that of the Project Area and its surrounding communities. In the rapidly changing context of increasing visitor numbers and accelerated development within the Greater Lumbini Area, driven notably by international and national investments in regional infrastructure, this chapter concludes by discussing the current and future challenges linked to the management of Lumbini beyond the completion of the LMP and the sustainable future of its wider region.
The effects of natural disasters on religious tourism sites: earthquakes in the spiritual heart of Italy.
Authors: di Giovine Michael , Ascione Elisa
Published: October 2020

Based on three years of ethnographic fieldwork including participant observation, site inspections within the forbidden 'red zone' of towns such as Norcia, Amatrice and Campi, and interviews with locals, administrators, tourism industry workers, and clergy, this chapter examines the physical and spiritual impacts of the series of earthquakes in Central Italy in 2016, and explores how different stakeholders (e.g. tourist guides, local authorities, shopkeepers, priests, nuns and monks, and tourists) have framed the role of tourism in the area and how touristic practices re-signify the value of places and their associated moral ideals after environmental disasters. In addition, the chapter examines the dialectical effects of a double environmental transformation on sites: how a natural disaster - unplanned and uncontrollable by social actors - impacts the tangible and intangible fabric of pilgrimage sites, and how those subsequent social interventions likewise impact religious tourism and its stakeholders as well as the wider environment itself.
Religion, the environment, and sacred places: lessons learned and future directions.
Authors: Olsen Daniel H. , Shinde Kiran A.
Published: October 2020

The environment, with its various facets and dimensions, and sacred places and their intersection with religious tourism, have been the central focus of this book. In this final chapter, the authors reflect on some of the insights offered by the contributors on the interconnections between religious tourism and the environment that highlight the complexities surrounding the environment and sacred places. In outlining some of the limitations of this book, the authors also suggest avenues for future research in this area of inquiry.
Magnetic shear effect on plasma transport at T
e/T
i ∼ 1 through electron cyclotron heating in DIII-D plasmas
Authors: Yoshida M. , McKee G.R. , Petty C.C. , Grierson B.A. , Nakata M. , Rost C. , Rhodes T.L. , Ernst D.R. , Garofalo A.M.
Published: October 2020

The effect of magnetic shear on plasma transport for an electron to ion temperature ratio (T
e/T
i) near unity has been explored in DIII-D utilizing electron cyclotron heating (ECH). Previous reports showed that significant confinement degradation occurred at T
e/T
i ∼ 1 in positive shear (PS) plasmas in DIII-D, whereas reduced confinement degradation was observed in negative central shear (NCS) plasmas. In this study, plasma transport in weak magnetic shear (WS) plasmas with ECH is investigated and compared with that in NCS and PS plasmas. Here the magnetic shears (

s
ˆ

) are

s
ˆ

> 0.5, ∼0 and <-0.1 in the core region (ρ∼ 0.3–0.4) of PS, WS and NCS plasmas, respectively, and flat or negative inside ρ∼ 0.4 in the WS and NCS plasmas. Weak magnetic shear is found to be effective in minimizing degradation of ion thermal confinement as T
e/T
i increases through ECH application, and an improved confinement factor of H
98y2 ∼ 1.2 is maintained, similar to NCS plasmas. At T
e/T
i ∼ 1, the ion thermal diffusivity around an internal transport barrier decreases when changing the magnetic shear from positive to weak or negative shear. Also, reduced local particle and momentum transport was indicated by steeper density and toroidal rotation profiles in the weak and negative shear regimes. Linear gyrokinetic simulations predict little change in growth rates of low-k turbulence with ECH application in the WS and NCS plasmas, which is consistent with the transport and profile analyses.
Development of mobile-based application for practical wood identification
Authors: Arifin M R , Sugiarto B , Wardoyo R , Rianto Y
Published: October 2020

Wood Identification is an important task, especially for wood anatomist. The identification process is required in many fields, such as custom ports, forest survey, and wood industries. However, expertise-in wood identification is limited due to a few wood anatomists. To enable wood identification can be performed in a broader area, a mobile-based application is proposed to realise these purposes. The paper presents the development of a mobile-based application for wood identification. A dataset of Indonesian commercial wood images of cross-section surface was collected from Xylarium Bogoriense, The Ministry of Environment and Forestry of The Republic of Indonesia. The images were collected using a smartphone camera at optical magnification level around 200 times and a minimum resolution of 12 megapixels. The collected images were then used to develop a deep learning-based algorithm to classify wood species. These images are considered as the training datasets, whereas testing dataset is collected in another session. The final model obtained through the training process is then stored in a cloud-based server at Research Center for Informatics, Indonesian Institute of Sciences. A mobile application, namely AIKO stands of Indonesian words-Alat Identifikasi Kayu Otomatis (Automatic Tool for Wood Identification), is developed to enable image acquisition and images transferring to the server. AIKO application sends the acquired image to the trained identification model in the server. The output of the identification model is the species name of the observed images. Besides species/botanical name, AIKO also provides information on trade names, specific gravity and density, durability class, strength class, commercial timber classification, and recommended utilization.
Parasitic Architectural Forms (PAF) S01.E01 “Prologue”
Authors: Baroš Tomáš
Published: October 2020

The aim of this paper is to outline the main functionality of Parasitic Architectural Forms (PAF), extend on potential utilization of it in the digital era, discuss the possibility of architecture being self-designed. I raised a question if architecture could be self-growing, self-developed and self-healing. This issue is being solved by this concept of PAF. Absence of artificial intelligence in the process of design in the architecture field offers a space for new research. Also, it generates options for yet uncharted views for experimental creation and urges us to ask of what are we, people, and computers currently capable.
Application of mathematical models in design and assessment of sewer network facilities
Authors: Csicsaiová R , Hrudka J , Marko I , Stanko Š
Published: October 2020

The application of mathematical models has been expanding in the field of sanitary and environmental engineering. Mathematical models are used in the design and assessment of sewer networks and their facilities. Sewer network models make it possible to create a model of hydraulic and Physico-chemical processes in wastewater flowing through the sewage network. The number of extreme rainfall events is increasing due to climate change. It causes a collapse in the infrastructure of urbanized areas. It is possible to investigate the flow of wastewater under extreme rainfall and to propose measures to eliminate adverse events using mathematical models. Nowadays, it is possible to use modern calculation procedures, which are used to dimension and assess existing facilities. This paper aims to focus on the application of numerical models in the design and assessment of combined sewer overflow chambers. The combined sewer overflow serves to carry away a part of the rain flows from the network to the nearest suitable receiving water body. Their main task is to reduce the uneven load of wastewater treatment plants by rainwater. The combined sewer overflow chambers distribute the inflow into the flow going to the wastewater treatment plant and the lightened flow going to the receiving water. The aim of this paper is to summarize the knowledge of CFD modelling and to get acquainted with the basic principles. In brief, the normal flow describes its simulation using two basic models. Finally, it focuses on the recapitulation of foreign studies and their use in the assessment and design of relief chambers and regulatory objects of the single sewer networks.
Share of the volume of work types and financial costs according to the stages of construction of reinforced concrete monolithic buildings
Authors: Doubek R
Published: October 2020

The aim of the paper is to evaluate the technological and economic demands on the construction of multi-storey reinforced concrete monolithic buildings for administrative purposes incorporating the stages of construction, technological stages and selected partial construction processes.

The entry criteria for objects that are included in monitoring and evaluation are their identical location, used technologies, mechanization, built-in materials and their purpose.

The purpose of the paper is to prepare tables for the professional and academic public for a rough idea of the proportional representation of time and financial consumption in the construction of this type of object, for selected stages of construction, technological stages and selected partial construction processes.
Analysis of the efficiency of sewerage with the illegal rainwater inflow
Authors: Hrudka J , Marko I , Šutúš M , Stanko Š
Published: October 2020

In our research, we are focused on analysing the impact of illegal rainwater connections on the sewage network. During the normal operation of the sewage network, rainwater cannot be present. These heavy rains flows are extreme during rain events and the sewerage system is significantly overloaded and functionality it is reduced. Our study is based on the real data of the sewerage network and selected area of interest. In the assessment of illegal connections of rainwater, we use rainfall data according to the relevant ombrographic station.
Old cement-based render as the cause of extremely low carbonation of 100-year bridge concrete
Authors: Húlek L , Bačuvčík M , Gašpárek J
Published: October 2020

In-situ research and laboratory examination provided on concrete core samples from old bridge structures confirmed that a thin layer of ordinary cement-based render coat protects the underlying concrete from carbonation. The average measured value by phenolphthalein test was less than 2 mm after more than 100 years of service life in exposure class XC3 of EN 206. Low carbonation depth is explained by the presence of a thin (2-4 mm) layer of the protective render coat (PRC) situated on the bridge concrete. The place, where the PRC was of good quality was almost impermeable and the carbonation of the concrete underneath was even 0 mm. If the PRC locally spalled, the carbonation depth of the same concrete, at the same structure and environment reached at this place even more than 80 mm. It was observed that low carbonation of concrete significantly depends on the non-permeability of the PRC. A narrow free space filled with the carbonates causes increased non-permeability of the PRC creating thus the built-in limestone-based (anti-carbonation) barrier with the ability to dramatically reduce CO2 penetration into the beneath concrete over time. Values from in-situ and laboratory research are presented in the article with the explanation of these phenomena.
Shear strength of in-plane loaded cross laminated timber beam elements – experimental and theoretical investigation
Authors: Jeleč M , Strukar K , Rajčić V
Published: October 2020

Cross laminated timber (CLT), as a versatile engineered timber product, has in recent years become well-known and of global interests. The orthogonal laminar structure allows for application as beams, walls or panels for both out-of-plane and in-plane loading conditions. The work presented here concerns experimental investigations of in-plane loaded CLT beams, as very relevant from a practical engineering point of view due to reinforcing effect of transversal layers with respect to stress perpendicular to the beam axis. Experimental results are used for comparison and validation of design proposals from the literature, with the main focus on the shear failure mode III in crossing areas between orthogonally bonded longitudinal and transversal lamination. By using the assumed shear strength values from the literature, analytically predicted shear carrying capacities show good agreement with the experimentally obtained. Although further experimental validation is needed, obtained results indicate that suggested design proposals should be considered in ongoing revision work of Eurocode 5.
Evaluation of frost resistance of various blended binders
Authors: Kardosova E
Published: October 2020

The use of blended binders using alternative raw materials is one of the key areas of sustainable development in terms of reducing CO2 in the atmosphere. This approach reduces the proportion of energy-intensive clinker in cement when satisfying technical parameters. The paper presents a proposal of variants of blended binders with the application of fly ash, blast furnace slag and perlite for their use in building mixtures. The durability of the mixtures is assessed on the basis of testing the frost resistance of mortars. Test specimens were produced according to STN EN 196-1. The samples were subjected to 25 freeze-thaw cycles, and both the flexural and compressive strength were then determined, to express a durability factor. Except for slag as a standard component of blended binders, perlite appears to be a perspective material; it meets a limit for durability factor when used as a 30% substitution for cement, as well as when used in ternary composition with slag. Fly ash showed weak frost resistance, even when used with a suitable perlite.
Analysis of mechanical properties of I-beam with web from transparent wood
Authors: Kanócz J , Bajzecerová V , Karl’a V
Published: October 2020

This article contains a brief information about history of transparent wood, its fabrication process and its physical and mechanical properties. The main goal of this article, however, is to find whether transparent wood is a suitable material for load-bearing architectural constructions. This is achieved by using numerical analysis of I-beam with web from transparent wood (and various types of it) and comparing its results with the same sized beam with web from OSB (oriented strand board) and web from glass, which are both successfully used for such applications nowadays. Suggestions on how to use transparent wood as a load-bearing material are also presented in the article.
Alternatives of solar systems and their analysis
Authors: Kosican J
Published: October 2020

This study negotiates with percentage fraction for heating and hot water of various solar systems. Research building of the Technical University of Košice was selected. For this analysis, we used simulation appropriate simulation software, which replicates solar systems and calculates the production of the proper solar system. If we consider DHW solar ratio, the fifth alternative, which includes a combination tank system (heating buffer tank) with an outside heat exchanger and a swimming pool, is the most productive. Nonetheless, in accordance of overall solar fraction, the top choice is alternative 4, which is a mix of DHW tank system with a heat exchanger inside the tank. At the end, the outcome demonstrates that, mix of DHW tank and buffer tank for space heating with a swimming pool, that is alternative 6, seems to be the worst case. Efficient usage of different systems based on renewable energy sources and their applications secures Investigated centre mentioned before.
Compressive strength of concrete specimens with inclusions
Authors: Kovac M , Sabol P , Kusnir S , Kusnirova D , Rovnak M
Published: October 2020

Large diameters and grain aggregates and/or reinforcing bars can have a negative impact on the strength of concrete elements. Tests of concrete specimens with inclusions under uniaxial compression should contribute to a better understanding of the process of failure of concrete elements. The identification of the unstable phase of the cracking and quantification of the effect of diameters, positions, distances, number and material of inclusions, as well as the relative size of inclusions and matrix on compression strength could provide information for an explanation of the causes of the size effect in compressed structural elements. The introduction of the article provides a brief overview of the problem of concrete structures subjected to uniaxial compression. Attention is paid to the failure mechanisms in the process of loading the test specimens from initial crack formation to specimen collapse. The second part is devoted to the investigation of the size effect of varying dimensions of the test specimens with one or three inclusions.
Environmental assessment of existing pavements asphalt layers for production of new asphalt mixtures
Authors: Kovács R , Mandula J
Published: October 2020

Road construction requires a large amount of construction materials. During asphalt pavement construction it is natural aggregate and asphalt binder in particular. Their ratio varies depending on whether they are applied in an asphalt pavement as a wearing, binder or base course. Nowadays, pressure of public opinion on responsible environmental behaviour and effective use of financial resources create an optimal space for assessment of building materials from pavement layers. According to the EAPA (European Asphalt Pavement Association) data from 2017 the wearing courses accounted for 90 % of all pavement layers in European Union. In Slovakia their representation is also dominant. While in Western Europe reassessment of existing asphalt layers by recycling technologies has been used to the maximum, in Slovakia the reassessment was out of interest of construction companies. With the arrival of new machinery, legislation amendment and social pressure on responsible environmental behaviour, the strategy of some construction companies in Slovakia is also changing. The reassessment of existing asphalt layers for production of new asphalt mixtures goes to the forefront of the interest. This article summarizes necessary steps to achieve an increase in the re-use rate of R-material by hot-mix asphalt recycling technology in asphalt mixing plants.
Comparative analysis of magnesium oxide boards properties
Authors: Mokrenko D , Kozlovská M
Published: October 2020

The current sustainability trends pose high demands on building materials and products. Those with potential to be labelled as an environmentally-friendly product or technology are getting preferred. One of the natural resources with such potential is magnesite, whose resources are widely found in Slovakia. The article deals with analysis of the magnesium oxide board properties as the most popular MgO-based building product. The comparative analysis of magnesium oxide boards with other available building boards (plasterboards, oriented strand boards) is included in the article and especially from the point of magnesium oxide boards’ benefits.
The conformity of the tools of selected software programs for 4D building modeling
Authors: Nechyporchuk Y , Bašková R
Published: October 2020

4D modeling is a part of the BIM (Building Information Modeling) platform. It represents the design approach, when the building is designed not only in space (3D) but also in time (3D + time). The aim of the article is to compare Autodesk Navisworks and Synchro Pro in terms of the conformity with the requirements for creating and using 4D building models. The introduction represents the resource search where the advantages and ways of using 4D modeling for construction and the situation of its applying in Slovakia and abroad are summarized. Besides, the 4D model of the building Water World, created in Autodesk Navisworks and Synchro Pro, is introduced there. In the conclusion, there is a comparison of the tools of this software in user’s several points of view.
Experimental investigation on bond-slip behavior of selfconsolidating rubberized concrete
Authors: Strukar K , Jeleč M , Kalman Šipoš T , Grubišić M , Lukić S
Published: October 2020

Reducing the industry’s impact on the environment is the goal of sustainable construction which can be achieved by using renewable and recyclable resources such as scrap tire waste. Great potential of this waste is found in construction mostly as a partial replacement of mineral aggregate in concrete and mortars, asphalt mixtures and geotechnical works. Previous studies on the selfconsolidating rubberized concrete (SCRC) are mostly concerned with mechanical properties of rubberized concrete. However, in order to allow structural application, it is also necessary to investigate bond-slip behavior of SCRC and reinforcement bars. Thus, in this paper pull-out tests are performed on 24 cubic samples with reinforcement confinement. Three different SCRC mixtures are made, first with concrete without rubber particles as reference mixture, second with 10%, and third with 15% rubber particles and 5% silica fume. The other parameter varied is diameter of steel bars (∅12, ∅16, and ∅20 mm). From the results obtained in experimental investigation, key bond parameters and failure modes of SCRC are compared with bond-slip behavior of self-consolidating concrete (SCC).
Numerical nonlinear analysis of a membrane structure subjected to dynamic load
Authors: Stulerova L , Kapolka L , Kmet S
Published: October 2020

The aim of this paper is the numerical analysis of a thin technical textile in shape of hyperbolic paraboloid. It is the membrane structure, which can function only in tension and it is geometrically nonlinear, therefore nonlinear analysis has to be carried out. In this case, the structure was subjected to the dynamic loads effects. Natural vibration was applied as a fundamental dynamic characteristic. All of this results in natural frequencies and mode shapes and deflections. Acquired results describe the dynamic behaviour of nonlinear system. This part of the analysis could represent a first step in the dynamic analysis. To complete the dynamic analysis of the membrane structure, the forced vibrations as nonlinear time history analysis will have to be performed in a future.
The effect of CO2 on the strength characteristics of cement composites based on recycled rubber from waste tires
Authors: Svoboda J , Vaclavik V , Dvorsky T , Charvat J , Macalova K , Papesch R
Published: October 2020

This paper presents the results of a research into the use of a combination of recycled rubber from waste tires as a 100% aggregate replacement in the production of cement composites. The aggregate was replaced with rubber recycled material in two ratios. At a ratio of 50/50 and a ratio of 40/60 fraction 0/1 mm and fraction 1/3 mm. The test specimens were further subjected to CO2 effect in a Lamart laboratory chamber, where CO2 effect was simulated as equivalent to an aging period of 50 years. The presented results show that the effect of CO2 reduces the strength characteristics of the composite compared to the comparative samples.
LCA analysis of Slovak residential building
Authors: Tomková Ž
Published: October 2020

Building industry is main contributor to greenhouse gas (GHG) emissions. According to goals of Paris agreement to achieve temperature rise below 2°C a year and then below 1,5°C a year, we need to find where are our biggest possibilities of improvement. Focus of this paper is on residential buildings built in Slovakia. With population growth also demand for apartments rises. With residential building development comes possible place for improvement. That is why main goal of this assessment is to analyse current state of our residential building fond using eToolLCD software and cradle to grave approach. Selected environmental impact of this analyse are, global warming potential (GWP), ozone depletion (OP), acidification potential (AP), eutrophication potential (EP), photochemical ozone creation potential (POCP), abiotic depletion potential of elements (ADPE), abiotic depletion potential of fossil fuels (ADPF) and also use of primary energy resources (PENERT). Assessed residential buildings are first part of larger investigation in this sector.
Analysing the cumulative energy demand of external bearing walls
Authors: Wolfova M
Published: October 2020

The assessment of environmental properties of buildings is now commonly using a life cycle analysis (LCA). Due to the rapidly evolving construction industry, LCA research is carried out in many areas, from building materials and components to overall building system. Life Cycle Assessment (LCA) is a tool used to compare environmental impacts along the life cycle of products or services. This paper presents an evaluation and comparing of two external bearing walls of different material compositions regarding the materials´ total energy consumption within the cradle to gate boundaries. Impact categories were calculated by the software SimaPro using Cumulative Energy Demand (CED) method and applying the Ecoinvent database. A renewable (biomass, wind, solar, geothermal, water) and non-renewable (fossil, nuclear, biomass) energies were under consideration. The composition with brick as a core wall material achieved worse results in all categories than the wall composition with aerated concrete block.
Conductive natural and waste rubbers composites-loaded with lead powder as environmental flexible gamma radiation shielding material
Authors: El-Khatib Ahmed M , Doma A S , Badawi Mohamed S , Abu-Rayan Asmaa E , Aly N S , Alzahrani Jamila S , Abbas Mahmoud I
Published: October 2020

It is well known that materials with lead (Pb) content are very effective as protective materials against radiation. Natural rubber (NR) has been loaded with 30 phr of N220 black (critical concentration) as a conductive and reinforcing filler. These rubber matrices are loaded with different concentrations of Pb powder (up to 100 phr) as filler. Gamma attenuation study was carried out using 3″ × 3″ NaI (Tl) (scintillation detector) gamma-ray spectrometer for (Cs-137), (Co-60), (Ba-133), and (Eu-152). The effect on the shielding property of Pb/NR composite was studied by varying the content of Pb and photon energy. It was found that the addition of Pb filler remarkably increases the linear attenuation coefficient (μ) of Pb/NR composites, especially for low photon energy. Linear attenuation coefficient experimental measures and theoretical calculations (using the XCOM code) were performed. It was noted that there is a reasonable agreement between measured and calculated results. In this paper, gamma-ray radiation shielding parameters are also studied for composites based on waste rubber. Its experimental results showed that Pb/W/NR composites have better γ shielding ability compared to Pb/NR ones at the Pb contents so, these are promising materials for fabricating protecting clothes against radiation in addition to their low cost and effective aid to get a clean environment.
Corrosion behavior of Cr-bearing steels in CO2-O2-H2O multi-thermal-fluid environment
Authors: Yuan Juntao , Zhu Kaifeng , Jiang Jingjing , Zhang Huihui , Fu Anqing , Li Wensheng , Yin Chengxian , Li Fagen
Published: October 2020

Multi-thermal fluid is used to enhance heavy oil recovery, but it also causes severe corrosion failure of metallic tubing and its mechanism is still open to debate. In the present work, the corrosion behavior of commercial steels with different Cr content (3 wt%, 9 wt%, and 25 wt%) in simulated CO2-O2-H2O multi-thermal fluid environments were studied by immersion corrosion test and microstructural characterization. The results exhibit that the Cr content of steel determines the type of corrosion products. The less protective corrosion scale is mainly composed of FeCO3, (Fe, Cr)3O4, and Fe2O3, which is formed on the surface of 3Cr and 9Cr steels. The protective corrosion scale is mainly Cr2O3, which is formed on the surface of 25Cr steel. Only when the Cr content in steel is sufficient (i.e. 25 wt%) to repair the serious depletion of Cr in the metal near the scale/metal interface in time, can protection of the corrosion scale be sustained, to improve its ability to resist the corrosion of multi-thermal fluids.