bluuebunny/crossref_metadata_2025 huggingface dataset:
Using air thermal time to predict the time course of seedling emergence of Avena sterilis subsp. sterilis (sterile oat) under Mediterranean climate
Authors: Bastida Fernando , Laleh Kambiz Mootab , Gonzalez-Andujar Jose L.
Published: April 2022

Avena sterilis subsp. sterilis (sterile oat) is a troublesome grass weed of winter cereals both in its native range encompassing the Mediterranean up to South Asia, and in regions of America, Northern Europe and Australia where it is introduced. A better understanding of seedling emergence patterns of this weed in cereal fields can help control at early growth stages benefiting efficacy under a changing climate. With this aim, the objective of this research was to develop and validate a field emergence model for this weed based on cumulative air thermal time (CTT, ℃ day). Experiments for model setting and evaluation were carried out in experimental and commercial fields in southern Spain. Two alternative models, Gompertz and Weibull, were compared for their ability to represent emergence time course. The Weibull model provided the best fit to the data. Evaluation through independent experiments showed good model performance in predicting seedling emergence. According to the developed model, the onset of emergence takes place at 130 CTT, and 50% and 90% emergence is achieved at 448 and 632 CTT, respectively. Results indicate that this model could be useful for growers as a tool for decision-making in A. sterilis control.
Exact solution of the one-dimensional neutron diffusion kinetic equation with one delayed precursor concentration in Cartesian geometry
Authors: Khaled S. M.
Published: April 2022

In this article we use one-dimensional, monoenergetic diffusion kinetic equation with one delayed neutron precursor concentration in Cartesian geometry to reconstruct the neutron flux of a reactor from the nuclear parameters, boundary, and initial conditions. The mathematical model is governed by a system of linear partial differential equations with prescribed boundary and initial conditions. As a matter of fact, the exact solution for any physical problem, if available, is of great importance which inevitably leads to a better understanding of the behavior of the involved physical phenomena. The present work represents an attempt for doing so, where the flux and precursor equations are solved by the help of Laplace transform in both spatial and time variables and consequently the exact expressions for the flux and concentration in space and time are established. We report numerical simulations as well study of numerical convergence of the obtained results.
A computational investigation of COVID-19 transmission inside hospital wards and associated costs
Authors: Moreno-Martos David , Foley Sean , Parcell Benjamin , Trucu Dumitru , Eftimie Raluca
Published: April 2022

The COVID-19 pandemic has placed a particular burden on hospitals: from intra-hospital transmission of the infections to reduced admissions of non-COVID-19 patients. There are also high costs associated with the treatment of hospitalised COVID-19 patients, as well as reductions in revenues due to delayed and cancelled treatments. In this study we investigate computationally the transmission of COVID-19 inside a hospital ward that contains multiple-bed bays (with 4 or 6 beds) and multiple single-bed side rooms (that can accommodate the contacts of COVID-19-positive patients). The aim of this study is to investigate the role of 4-bed bays vs. 6-bed bays on the spread of infections and the hospital costs. We show that 4-bed bays are associated with lower infections only when we reduce the discharge time of some patients from 10 days to 5 days. This also leads to lower costs for the treatment of COVID-19 patients. In contrast, 6-bed bays are associated with reduced hospital waiting lists (especially when there are also multiple side rooms available to accommodate the contacts of COVID-19-positive patients identified inside the 6-bed bays).
Digital Twin Technology for Fusion and the Development of V-KSTAR
Authors: KWON Jae-Min , Team V-KSTAR Development
Published: April 2022

We briefly introduce a digital technology for fusion and how the technology is applied to develop the Virtual KSTAR (V-KSTAR). Aiming a comprehensive virtual platform for fusion researches, the V-KSTAR is developed with capabilities 1) to virtualize the KSTAR main device, 2) to handle various fusion data systemtically, and 3) to visualize fusion data in an integrated way. We also discuss the implications of the V-KSTAR for KSTAR researches along with a couple of exmaples to demonstrate the capabilities of the V-KSTAR.
Transgressive TV: Euphoria, HBO, and a New Trans Aesthetic
Authors: Macintosh Paige
Published: April 2022

While television shows Orange Is the New Black (OITNB) and Transparent have made headlines for their inclusion of trans performers and their debatably authentic takes on trans experiences, Euphoria signals a new era in trans representation, one that is defined by a “cool” trans aesthetic that epitomizes multiplatform television’s investment in trans as an edgy brand marker. Where HBO differs from Amazon’s Transparent and Netflix’s OITNB is in its investment in a new type of trans representation that disrupts the cinematic and television tradition in which trans characters remain closely associated with tragedy or are relegated to the recent past. While HBO utilizes both cable and video-on-demand (VOD) streaming services, its recent investment in trans discourses is in part a response to Netflix and Amazon Prime’s successful trans programming and indicative of the competitive value trans content offers content producers in the multiplatform era. Euphoria breaks new ground by offering a new aesthetic treatment of trans identity that invokes Gen Z’s ubiquitous use of social media, creative application of makeup, and nuanced approach to gender and sexual identities. The show’s stylized aesthetic, represented through hypermobile cinematography and surreal lighting, reflects this transgressive approach while also highlighting the show’s hypersubjective framing. Finally, Euphoria illustrates the crucial role of showrunner auteurs for HBO and, more specifically, the function of transgressive trans characters in Sam Levinson’s auteur brand.
Neutro Algebra and Neutro Group
Authors: Das Suman , Das Rakhal , Pramanik Surapati
Published: April 2022

This chapter improves and extends several definitions, properties, and applications of neutro-algebras. In classical algebraic structures, the laws of compositions on a given set are well-defined. In fuzzy algebraic structures, the laws of compositions on a given set are not well-defined exactly but with a membership value. This chapter examines those structures which have huge applications or strong potential for applications outside of mathematics, namely computer science or engineering. The study emphasizes that the nature of neutro-algebra and anti-neutro algebra differs from that of the classical algebra and fuzzy algebra. This chapter presents Venn diagram for neutro-function and establishes some relations between the partial algebra and neutro-algebra. The main contribution of the chapter is the introduction of the notion of neutro-group.
Cultural Routes as a Tool for Sustainable Tourism and Socio-Economic Development
Authors: Genç Ruhet
Published: April 2022

Connecting various attractions and tourist destinations within a country or across many countries, cultural routes rely on a region's cultural legacy to give learning opportunities and tourist delight. These heritage-based routes that exist in all parts of the world, on various scales, features, and purposes, are considered an important tool for the social and economic development of tourism destinations via cultural tourism and feature in tourism marketing that offers various interests such as gastronomy, arts, linguistics, architecture, spirituality, religion, and sports. This chapter examines the contribution of cultural routes to sustainable tourism and socio-economic development due to the significance they have. The methodology will be literature review and critical evaluation of the findings.
Conceptual Model of Sustainable Development of Cultural Tourism With a Hybrid Approach
Authors: Salek Farokhi Omid , Hosseini Seyedeh Yasamin
Published: April 2022

In this study, an attempt has been made to systematically review the findings of the studies conducted by other researchers in the field of sustainable development studies of cultural tourism using an interpretive approach and a systematic meta-combination method. Then, based on the hidden content analysis strategy, the extracted codes are identified in the form of categories. Finally, the authors present a conceptual model. In this research, valid scientific databases were reviewed, and selected articles were identified using CASP criteria. Based on this, 104 primary codes in the form of 29 categories of primary and secondary categories are identified, and the four central codes are components, effective factors, consequences, and challenges of sustainable development of cultural tourism. Also, a conceptual model of sustainable development of cultural tourism and tourist destinations in need was presented. Finally, the validity of the research results with Kappa Cohen index in SPSS software was confirmed based on the opinions of experts outside the authors of the research with a size of 0.712.
Developing Literary Tourism to Support Local Culture and Tourism
Authors: Erkoçi Ilda
Published: April 2022

Literature can provide tourism with new destinations, which can in turn foster cultural and economic development. This chapter contends that Shkodra has potential for the development of literary tourism, and that making better use of literature as part of the cultural heritage and tourism offer in this city would have multiple benefits. Not only would this increase interest in literature as well as create stronger connections with the literary tradition, but it would also offer unique experiences, help connect with local communities, and even support local economy. By using autoethnography as a starting point, this chapter will provide a model on how to use literature as part of cultural tourism by highlighting significant literary locations in Shkodra, Albania, which has been chosen as a case study. That will then be followed by an analytical discussion of the strategies to be used so as to bring literature to the attention of people.
Favela Tour Experience
Authors: Gonçalves da Silva Natalia , Ribeiro de Almeida Cláudia
Published: April 2022

Tourism performed in slums has been raising the interest of researchers and generating controversial opinions regarding its objectives. For this reason, the present study aims to verify the impacts of the slum tours in the host communities by analyzing the pre-concepts and ideas associated with this tourism activity through the collection of data attained by the application of a survey, comparing it with the results obtained during the visits to the slums of Rocinha and Santa Marta. For its validity, the research performed by different authors are used as a guidance reference allowing the reader to have a broader perspective of the phenomena here presented. As for the obtained results, the study shows that the benefits of the tours for those communities can be divided in tangible (offers economic advantages) and intangible (offers change in perspective and reduction of the prejudice).
Challenges in Safeguarding Traditional Festivals Facing Tourism Pressure
Authors: Kwan Kate Chi Wo
Published: April 2022

This chapter reports on the findings of a study that investigated the challenges in safeguarding two of Macao's and China's nationally recognized intangible cultural heritage festivals which are facing tourism pressures, namely 1) Macao Feast of the Drunken Dragon and the Lion Dance Gala and 2) The Beliefs and Customs of Na Tcha. Based on the findings, some recommendations are formulated that adopt a community-based approach to safeguard traditional festivals. Face-to-face interviews were conducted with festival organizers and volunteers who empathize with the values of the traditional festival customs and their related cultural spaces.
Understanding the Service Quality Dimensions and Achieving Resilience in Service Retail
Authors: Raut Sachin Kumar , Sakpal Subodh , Soni Rashmi
Published: April 2022

Innovation has increasingly supported the way businesses across the globe operate; however, this phenomenon often increases uncertainty around supply chain disruptions and management. The COVID-19 pandemic clearly reveals the lack of resilience in the supply chain domain, and the business failures show the impact of disruptions may have on a global network scale as individual supply chain connections and nodes fail. This cascading failure also has an impact on service quality dimensions of a business. Service quality advances have profoundly changed the way service organizations and consumers interact. This impact can be observed across sectors and industries. Service quality has become a popular area of researchers and academic investigation and has become recognized as a key factor in differentiating service products and building competitive advantage. Any shortcoming of a lack in service quality is easily identified and is translated into negative reviews on social media through word-of-mouth and other channels.
Blockchain Technology Aptness for Improving Supply Chain Visibility, Resiliency, and Efficiency
Authors: Vanteddu Gangaraju , Bandyopadhayay Asit
Published: April 2022

Frequently recurring supply chain disruptions due to natural and manmade calamities are highlighting the importance of the supply chain ability to prevent, withstand, and overcome disruptions of all kinds. Blockchain technology (BCT), a key Industry 4.0 technology, with its inherent strength as an open-sourced distributed database with the immutability of transactions has the potential to transform traditional supply chain (SC) operations. In spite of the potential advantages of the BCT in the supply chain management (SCM) area, the adoption of this novel technology is still in its very early stages. This chapter per the authors proposes a quality function deployment (QFD)-based strategic decision support tool to determine the aptness of BCT adoption in a given SC context. In addition, the proposed tool also allows us to understand the maturity of BCT capabilities in addressing the key SC performance aspects. The application of the proposed tool is explained through a couple of illustrative examples.
Supply Chain Building Blocks and Post-COVID-19 Recovery Measures With Artificial Intelligence
Authors: Patnaik Priyadarsini
Published: April 2022

Supply chain reach is vast and touches every aspect of business. As profitability of any business is directly impacted by its inventory, so any basic changes in operations would impact its performance. However, established supply chain paradigms are no longer valid as they are shaken up by VUCA economy, demographic change, sustainability, globalization, digitization, rise of ecommerce, political turmoil, social media, buying behaviour, and most importantly, by COVID-19. This COVID-19 pandemic crisis has taken over the world and brought additional challenges at an unprecedented scale. Since identifying and structuring the problem are the first steps towards effective SCM, so redesigning the distribution strategy is the need of the hour. Companies should innovate with data and new digital technologies to increase automation in their core process to forecast predictive analysis for greater customer experience and harness the disruption. In the context of disruption, this study explored how to utilize and optimize supply chain tools and models to make decisions during times of disruption.
Ethical Supply Chain Practices to Achieve Supply Chain Resilience
Authors: Fritz Morgane M. C.
Published: April 2022

Following the COVID-19 pandemic, ethical supply chain practices have been in the focus of several supply chain stakeholders such as firms, suppliers, government, and consumers. The pandemic caused a disruption that forced supply chains to reorganise their activities and sometimes take unethical decisions to ensure the business survival or satisfy customers. In light of several scandals, stakeholders require to increase transparency in the supply chain and recent norms on sustainable procurement highlight the importance of sustainable procurement in this mission. The chapter revises all key concepts of business ethics, supply chain practices, and supply chain resilience to explore, through the COVID-19 pandemic, unethical supply chain practices and propose solutions and recommendations based on practitioners' and researchers' studies.
Sustainable Green Supply Chain Management Trends, Practices, and Performance
Authors: Gupta Rahul
Published: April 2022

Innovative adoption of green supply chain management (GSCM) practices has witnessed a great surge in the last couple of decades. Its positive impact on the individual, society, and environment advocates the organization's commitment to progressively work with all stakeholders. Efforts are accelerated for identifying and understanding the opportunities to support green practices. Global warming and climate change have warned that scarce natural resources are not forever GSCM practices help to mitigate these hazards and ideologically enhance sustainability. Stake holders are committed to reuse, reduce, redesign, and recycle products in support of waste reduction and sustainable environmental protection. The sustainable supply chain is integrating sustainable environmental progressions into processes like selecting suppliers who ensure green manufacturing, buying green raw material, designing, assembling, and distribution with reverse logistics. Current research discusses sustainable green supply chain concepts, present and future trends, and performances.
The Impact of Cyber Attacks on E-Governance During the COVID-19 Pandemic
Authors: Jhanjhi N. Z. , Ahmad Muneer , Khan Muhammad Amir , Hussain Manzoor
Published: April 2022

A cyber-attack can damage data, computer programs, and network one or more computers through applying different methods and cybercriminal's activities to steal information. The increasing of new technologies among the users facilities them. The cyber-attacks are growing tremendously. E-governance is an application of IT and giving online services. These days the world is completely focused on creating social distance among the people, and billions of peoples around the world are working from home (online activities) and shops, and businesses are closed in the COVID-19 pandemic, which the WHO recommended. A remarkable cyber-crime has been recorded by the researcher's study in this environment, affecting society and businesses. This research's primary objective is to find cyber-attacks that steal information in the COVID-19 pandemic and assess the user loss. The results of five years have been compared on the machine learning techniques.
Applying Decision Tree for Hiding Data in Binary Images for Secure and Secret Information Flow
Authors: Chhajed Gyankamal J. , Garg Bindu R.
Published: April 2022

In today's digital world, it is noticeable that images are transferred in binary form which carries significant and confidential information. To secure and keep such information unnoticeable is the prime concern during transmission. Information hiding as watermarking or secret messaging are most acceptable ways to attain this. In this direction, a new information flow system using data hiding approach is proposed in this chapter. A decision tree is applied for locating the most suitable blocks for data hiding in the presented technique. Decision trees are one of the best techniques used as a classifier. In this approach, the decision tree classifies a particular block to be selected for hiding information, based on the LURD pattern of 3X3 pixel block of image and the blocks of information to be hidden. For security, information is encrypted and then scattered in the image. The receiver can retrieve the data without the original image. The results prove that the proposed scheme is capable of minimizing distortion caused due to data hiding.
Developing Communication and Inclusive Literacy Skills Among Children With Profound Intellectual and Multiple Disabilities
Authors: Nunes Clarisse , Oliveira Nuno David
Published: April 2022

Literacy assumes a special relevance in human life. However, the conventional literacy concept is limited and often not accessible to some students with disabilities, such is the case of children with profound intellectual and multiple disabilities (PIMD). Given the specific nature of these children, this chapter develops the idea of inclusive literacy and explores the concept of the multi-sensory stories (MSS) as a strategy that can help children with PIMD to develop communication and literacy skills. The chapter is organized in two parts. The first investigates the concept of literacy and explores the idea of inclusive literacy and the role that MSS can play in the development of communication and literacy skills. The second is based on a research project carried out in Portugal, which shows how the use of the MSS can help children with PIMD to develop communication and literacy skills. This chapter is integrated in the theme learning and teaching how to read and aims to promote a reflection about literacy and its teaching to children with PIMD.
Parent-Child Interaction and Communication in the Early Years
Authors: Fuertes Marina
Published: April 2022

Verbal interchanges (with family, caregivers, and peers) occur within an interpersonal relational context that adds social meaning, personal values, and social-cultural codes to the linguistic contents. Through positive transactional interchanges, children gain self-agency, self-esteem, and become active social actors. In this study, the authors investigate the association between the parent's type of verbalizations (number of suggestions, directions, orders, positive and negative feedback, teaching, questions) and the quality of their interactive behavior (e.g., empathy, challenge, cooperation, dialogical interaction) during a collaborative activity with a child. Forty parent-child dyads (30 mothers, 10 fathers), with children ranging from 3 to 5-years old, were observed while manufacturing a product of their choice for 20 minutes using predefined materials and tools. Videos were scored using Tandem scales. The present study describes parents' verbal and non-behavior, indicating that both types of behaviors are linked, generating specific learning, affective, and social micro-contexts.
Evolutional Supply Chain Management and Strategy
Authors: Higuchi Toru
Published: April 2022

At the beginning of this chapter, SCM and related concepts such as physical distribution, business logistics, and company groups are explained, and the areas of difference among them are clarified. In the middle of this chapter, the framework of a supply chain and SCM are described. Important factors about SCM and drivers changing the supply chain management and strategy are proposed. At the end of this chapter, the case of the pencil supply chain is introduced to illustrate the evolutional SCM and supply chain strategy. The pencil supply chain has a long history and has experienced dramatic changes due to product and process innovations.
Driving Forces and Factors of Amazon Effects
Authors: Zhengguang Yang
Published: April 2022

The development of Amazon so far is mainly due to Jeff Bezos's leadership. By sticking to a customer-focused policy and starting an online bookstore, he changed how retailers handle a wide range of books and everything, breaking Pareto's law and achieving a long tail. What's more, he politely responded to customer demands and devised a Fly Wheel strategy. By providing an effective product lineup at a low cost, Amazon has accelerated the virtuous cycle of increasing the ability to attract customers and has grown sales exponentially. On the other hand, Amazon invested the profits it earned in technology development and conducted research and development of cutting-edge digital technology. In addition, Amazon has been active in business models such as 1-click, FBA, Amazon Prime, and Marketplace. As a platformer, it has expanded its business to its own B2C and the B2B area for other companies' platforms.
Development of Characteristics and Thermal Properties of Ash Celadon Glazes in Thailand
Authors: Dechboon Nophawan
Published: April 2022

In this paper, we will study the development and comparison of characteristics and thermal properties of original celadon glazes and celadon glazes developed by adding black rice husk ash, Using Mae Rim black clay in Chiang Mai Province as raw material for the original celadon glaze (CG), including clay in the rice paddies, Kha wood ash and mixed wood ash. The raw materials for the development of celadon glazes formula were 14BR, 15BR, 20BR, 21BR, 27BR and 28BR, respectively. Using a triangular phase diagram system, Mae Taeng clay (MT), Kha wood ash (KWA) and black rice husk ash (BR) were used in the ratios of 40, 50, 60 and 70 wt.%, and using the red clay from Doi Saket, Chiang Mai as a coloring agent. Subsequently, the raw materials are ground and mixed to form a coating. Coated onto Mae Rim black clay test specimens. and fire the test specimen at 1250 °C in a reducing atmosphere. After that, the characteristics of the glazes after firing were tested, including crack, melt, flow, color appearance, and chemical composition. Thermal properties tests include the coefficient of thermal expansion and thermal shock resistance in temperature. The results showed that by comparing the original formula celadon glazes (CG) with the celadon glazes formula developed by adding black rice husk ash. crazing were reduced when adding more black rice husk ash. All formulations were melted at 1250 °C due to their CaO content of 55.0, 47.6, 41.0, 51.0, 47.9, 47.7 and 43.0 % respectively. From the chemical composition analysis with XRF, celadon glazes after firing in all formulas did not see any flow due to the content of SiO2 being 28.0, 28.8, 35.4, 26.7, 28.3, 27.9 and 31.1% respectively. The appearance of glazes after firing was more greenish-yellow when rice husk ash was added when using a color analyzer. Because the amount of Fe2O3 up to 4.6, 9.3, 10.4, 8.2, 9.1, 5.9 and 6.0% respectively from Mae Taeng clay and Doi Saket clay. The chemical composition of celadon glaze consists of CaO as the main component, followed by SiO2 and Fe2O3. The important thing is the chemical composition of the glazes was not found with lead and cadmium. The thermal expansion coefficient of celadon glazes at 25-1250°C decreased when adding more black rice husk ash. Finally, the percentage of strength loss after thermal shock temperature change was CG ˃ 20BR ˃ 21BR ˃ 27BR ˃ 28BR ˃ 14BR ˃ 15BR, respectively, using the Celadon Pottery Community Standards Test. (MorChor. 245/2013).
Influence of Heat Treatment on Microstructure and Performance of Degradable Mg Matrix Composites Reinforced with Hollow Glass Microsphere
Authors: Liu Lin , Yu Si Rong , Zhu Guang , Liu En Yang , Wang Kang
Published: April 2022

Recently degradable Mg matrix composites as a promising candidate for degradable downhole tools application have aroused extensive interest. In the present work, the effects of heat treatment (solution treatment and artificial aging) on the microstructure, mechanical properties and degradation behaviors of the newly developed hollow glass microsphere reinforced Mg-Al15-Zn6-Cu1.5 composites were investigated. The results show that the solution treatment causes the β-Mg17Al12 phase and Mg32(Al,Zn)49 phase to dissolve into the α-Mg matrix and the coarse eutectic τ-Al2CuMg phase to translate into blocky morphology. Aging treatment causes the β phase to precipitate at the grain boundaries or the edge of the residual second phases in lamellar and blocky morphology. After solution treatment, the ductility of the composites was significantly increased, while the following aging treatment could significantly increase the ultimate compressive strength (UCS), hardness and degradation rate. The composites solution treated at 420 °C for 20 h and aged at 200 °C for 24 h shows the higher degradation rate of 6.5 mg·cm-2·h-1 in 3 wt.% KCl at ambient temperature, with UCS of 471 MPa, Brinell hardness of 115 HB and fracture strain of 8.7 %, this outstanding comprehensive performance is more suitable for degradable downhole tools application.
A Brief Overview on the Extraction of Cellulose from Medicinal Plants for Advanced Applications
Authors: Selikane Dolly Grace Ann , Gumede Thandi Patricia , Shingange Katekani , Malevu Thembinkosi Donald
Published: April 2022

For over a thousand years, cellulose has been known as a polysaccharide that is readily available in nature. It is branded as a main constituent of the cell wall. Since the cell wall is produced by all plants, it is probably the amplest organic compound on Earth. The extraction of cellulose from medicinal plants is becoming a topic of interest. This is because compounds extracted from medicinal plants including cellulose are used as additives in pharmaceutical, neutraceutical, toxicology, and other chemical industries, for treating syphilis, kidney disorders, wound healing, ulcers, skin rash, gonorrhoea, and piles. Also, cellulose has been identified as useful for reinforcement and load-bearing purposes in composite materials due to its intrinsic stiffness and a high degree of crystallinity. However, the process of extracting cellulose, as well as the extent of the needed purity strongly depends on the application of the used polymers. This contribution focuses on medicinal plants as potential sources of bioactive cellulose.
The Effect of Chemical Activation Method in the Preparation of Activated Carbon from Local Phoenix Dactylifera Waste Stems
Authors: Al Gharibi Amira Sulaiman Rashed , Mjalli Farouk Sabri , Tarboush Belal Abu , Al Saadi Mohammed Abdul Hakim
Published: April 2022

Local date palm (Phoenix dactylifera) waste stems were used to prepare activated carbon (AC) using KOH, NaCl and ZnCl2 as activation agents. Carbonization was conducted at 600 °C for 2hr under nitrogen flow, followed by activation at 750 °C for 2 hr under carbon dioxide flow. AC was characterized using a scanning electron microscope (SEM), Attenuated total reflectance Fourier transform infrared (ATR FT-IR), Thermogravimetric analysis (TGA), Iodine adsorption, BET, micropores, and mesopores surface areas at different carbon-to-activation-agent-ratios (1:1, 1:2, 1:3). FT-IR spectra results showed a reduction in AC-NaCl bands compared to other AC, which indicates less functional surface groups. At 750 °C, the TGA analysis showed the carbon yield as AC-ZnCl2 > AC-NaCl > AC-KOH, however, among all samples, AC-NaCl at 1:2 ratio was the best in terms of iodine removal. This treated AC sample exhibited about 18.3 % maximum iodine removal, which indicates the high surface area and porosity with 550.4380 m2/g, 348.7432 m2/g, and 201.6947 m2/g BET, micropores and mesopores surface areas, respectively. In conclusion, the local Omani date palm waste stems can be used for AC production with a well porous structure using cheap and environmentally friendly salts as activation agents. In addition, the produced AC attained better adsorption characteristics among other alternatives.
Mechanical Crystallization of Amorphous Ti50Al30Ni20 Alloy Prepared by Mechanical Alloying
Authors: Urban Petr , Fernández Fátima Ternero , Louvier Rosa María Aranda , Lopez Raquel Astacio , Cuevas Francisco G.
Published: April 2022

Laser diffraction, Scanning Electron Microscopy (SEM), X-ray Diffraction (XRD), Transmission Electron Microscopy (TEM) and Differential Scanning Calorimetry (DSC) were employed to characterize the particle size, morphology and structure of mechanically alloyed Ti50Al30Ni20 alloy. Cyclic amorphous-crystalline-amorphous phase transformations were investigated during mechanical alloying, using high-energy ball milling technique. After 20 h of milling, an amorphous/nanocrystalline phase was obtained. This amorphous/nanocrystalline phase tended to transform into crystalline grains after 50 h of milling. In a cyclic phase transformation, the obtained crystalline phase is transformed into the amorphous phase after 70 h of milling. This amorphous phase crystallized through a single sharp exothermic peak at 590°C. On the basis of our results, the destabilizing effect of the defects created by the milling media (balls), which leads to the cyclic transformations, depends on the input energy and milling time.
Structures and Mechanical Properties of Pure Titanium by Different Nitriding Temperatures
Authors: Chen Tong , Koyama Shinji
Published: April 2022

The influence of different nitriding temperatures was investigated on the structures and mechanical properties of the treated specimens. Based on the research of nitriding temperature on the properties of pure titanium, the cause of the rresults can be discussed in this research. When the nitriding temperature is 1050°C, the cross-sectional hardness of the hardened layer reaches the maximum. At the same nitriding temperature, the bonding strength also reaches the maximum, which is related to the performance of the hardened layer. In summary, when the nitriding temperature is 1050°C, the nitriding of pure titanium can improve the overall performance.
Nonlinear and Linear Analysis of Langmuir Adsorption Isotherm for Removal of Copper from its Aqueous Solution Using Cucumber Peel
Authors: Gajendiran Vasu , Cuento Azucena , Selvaraju Sivamani
Published: April 2022

Adsorption is a unit operation of separating solute from solution using another solid material. Modelling of experimental adsorption isotherm data is an essential way for predicting the mechanisms of adsorption, which will lead to an improvement in adsorption science. The main aim of the present work is to analyse various forms of Langmuir isotherm for adsorption of copper from its aqueous solution using cucumber peel from the batch experimental data. The linearized and nonlinearized isotherm models were compared and discussed. In order to determine the best fit isotherm model, the determination coefficient (R2) and sum of square of error (SSE) for each model were used. The modelling results showed that nonlinear Langmuir model could fit the data better than other forms, with relatively higher R2 values (0.9879) and smaller SSE (0.013). The linear forms of Langmuir model had the maximum adsorption capacities deviated from the experimental data. The maximum adsorption achieved was 66.61 mg/g after validation with experimental results.
Characterization and Antibacterial Potential of Melt Compounded Acrylonitrile Butadiene Styrene/Copper Nanoparticle Composites
Authors: de Yro Persia Ada N. , Cariño Geraldine H. , Sargento Czharl John Dilbert C. , Quiachon Gerald Mari O.
Published: April 2022

Copper Nanoparticle (CuNP) is
mi
xed
as nanofiller to Acrylonitrile Butadiene Styrene (ABS)
to
pro
duce a material that can
control bacterial growth on material surfaces and improve antibacterial performance
. The
nanoco
mposite i
s produced
via melt compounding using a twin-screw
ext
ruder. Three samples are prepared with 0%, 1.5% and 3% Copper Nanoparticle
loading
. Th
e
samples
are
extruded
,
placed
in a mold and processed in a compression molding machine. The samples were characterized using Fourier Transform Infrared Spectroscopy (F
TI
R), X-ray Diffraction (XRD), Dynamic Mechanical Testing (DMA) and Antibacterial Testing. Results from FTIR shows presence of molecular vibrations of Acrylonitrile, Butadiene and Styrene groups with the presence of foreign substances identified as an addi
ti
ve used in commercial ABS production. XRD
showed t
he incorporation
of copper nanoparticles
in
the nanocomposites. DMA results shows that the incorporation of copper nanoparticles into the ABS matrix results
to
diverse effect on its mechanical and thermal p
r
operty. Lastly, antibacterial test showed that both 1.5 wt% CuNP and 3 wt% CuNP exhibited high effectivity on inhibiting Escherichia coli.
Index terms: Copper Nanoparticle, Acrylonitrile Butadiene Styrene, filler, nanocomposite, antibacterial material,
melt compounding, twin-screw extruder, Escherichia coli
.
Application of Novel Natural Biomass as Plant Growth Media in Renewable Energy Based Controlled Environment Growing System
Authors: Al Hinai Ali Said , Al Shibli Fatema Said Zahir Said , Natarajan Rajamohan , Al Kindi Ghassan
Published: April 2022

In this research study, the feasibility of renewable energy based green house was investigated for sustainable food production under arid climatic conditions. The novel hybrid biomass based matrix (Coco Date Palm Coir matrix), was synthesized from Oman’s date palm tree fibers and coconut coir. The characterization of the matrix was done in terms of bulk density (0.09 g/cc), particle density (0.23 g/cc), porosity (61%), moisture content (37.4%) and water holding capacity (65.6%). The hydroponic system based greenhouse employing evaporative cooling based climate control technique is used for the identification of novel plant growth matrix for the successful demonstration of plant growth. The experimental trials were conducted over the one-year period with dedicated cycles with average 7-8 weeks duration. The experiments conducted verified the growth of Lettuce over two cycles and the plant growth rate and wet biomass are recorded and compared. The growth of the plant attained at the end of week 5 was 175 mm and the maximum growth of 293 mm at the end of 58 days.
Synthesis, Characterization and Electron Beam Curing of Poly(Glycerol Sebacate Methacrylate)
Authors: Aranilla Charito T. , Barba Bin Jeremiah D. , Madrid Jordan F. , Margarito Marianito T. , de Yro Persia Ada N. , Basilia Blessie A.
Published: April 2022

Poly (glycerol sebacate) pre-polymer was synthesized and methacrylated to different degrees (PGSm-0.1, PGSm-0.2, PGSm-0.4) to impart processability using radiation technology. Spectroscopic analyses (FTIR and 1H NMR) confirmed the presence of ester linkage in the poly (glycerol sebacate) chain and the methacrylate group in the derivatives. The degree of methacrylation (DM) computed from the 1H NMR signal integration ranged from 0.1 to 0.4. The molecular weight and polydispersity increased with an increase in DM. The DSC thermograms suggested better elastomeric properties at ambient temperature, while the TGA showed no significant shift in the degradation parameters of PGS upon methacrylation. Electron beam curing of the PGSm samples was employed, and the resulting films were characterized for gel content, surface topography, and wettability. The crosslinked PGSm-0.2 and PGSm-0.4 samples exhibited high gelation at doses 5-50 kGy. However, no gelation above 15 kGy occurred in PGSm-0.1, suggesting that main chain scission reactions prevailed. The surface properties of the films obtained from the AFM and contact angle measurements revealed high surface roughness and wettability.
Near Unity Absorbance and Photovoltaic Properties of TMDC/Gold Heterojunction for Solar Cell Application
Authors: Khan Md Azmot Ullah , Adesina Naheem Olakunle , Xu Jian
Published: April 2022

In this paper, near unity broadband absorption of Van der Waals semiconductors on a metallic substrate, and their photovoltaic performances in the visible spectrum are simulated. Ultrathin layered semiconductors such as Molybdenum disulfide (MoS2), Tungsten disulfide (WS2), Molybdenum di-selenide (MoSe2), Tungsten di-selenide (WSe2), Molybdenum ditelluride (MoTe2), and Tungsten ditelluride (WTe2) can create strong interference by damping optical mode in their multilayer form and increase light absorption at their heterojunctions with noble metals. From our simulation, it is observed that this absorbance can reach up to 94% when the semiconductors are placed on a gold substrate. The optimum thickness of these semiconductors in their heterostructures with gold is analyzed to create resonant absorption to generate the maximum amount of current density. The power conversion efficiency of the designed Schottky junction solar cells is calculated from their current density vs bias voltage characteristics that ranges from 1.57% to 6.80%. Moreover, the absorption coefficient, dark current characteristic, electric field intensity distribution in the device, and carrier generation rate during light illumination are presented with a view to characterizing and comparing among the parameters of TMDC based nanoscale solar cell.
Study on Composite Material Failure of Reinforced Thermoplastic Pipes under External Pressure
Authors: Wang Lei , Lou Min , Wang Yang Yang
Published: April 2022

This paper examines the mechanical properties of reinforced thermoplastic pipes (RTP) under the influence of external pressure. We used the three-dimensional (3D) thick-walled cylinder theory, combined the 3D Hashin failure criterion with the theory of the evolution of damage in composite materials, considered their nonlinear mechanical behaviors, and introduced changes in the winding angle caused by deformation to formulate a model for the progressive failure analysis of RTP. The model was used to examine the failure sequence and external pressure capacity of RTP, and its correctness was verified by a finite element model. The results show that increasing the winding angle of RTP within a certain range can improve its external pressure capacity. When the winding angle exceeded ±50°, the failure of the RTP under external pressure mainly depended on the fiber fracture of the reinforced layer. With an increase in the ply number of the reinforced layer, the external pressure capacity of the RTP increased nonlinearly and its rate of growth gradually decreased.
Enzyme Induced Calcite Precipitation (EICP) for Engineering Application by Using Plant Based Biomaterials
Authors: Al Shibli Umayma , Alsaidi Maryam Said , Akhtar Aqsa , Qureshi Mohsin Usman , Zhao Yigao , Khalid Nauman
Published: April 2022

This research investigated the effect of reactant concentrations, reaction medium, urease enzyme source, and calcium source on the precipitation rate of calcium carbonate (CaCO3). This project is aiming to develop a biochemical reaction by using Enzyme Induced Calcite Precipitation (EICP) technique. This new technique would help in replacing the traditional cementation for the dune sand stabilization and promise an environmentally friendly and sustainable approach in the field of construction materials. Jack beans and soybeans were employed as a substrate to catalyze the urea hydrolysis in the study. The sources of calcium used in the experiments were calcium chloride (CaCl2), eggshell and sesame. In addition, both seawater and distilled water were used as a reaction medium to distinguish the effect on calcium carbonate precipitation. The experiments showed that using sesame at a concentration of 4.5 g, 5 g of urea and 6 g of jack bean at 60 mL of distilled water, is the best reaction conditions to precipitate 100.288 g of calcium carbonate. Further, the results indicated that the calcium carbonate precipitation enhanced by using 5 g of urea, 5 g of CaCl2 and 5 g of soybean at 50 mL of seawater. The precipitation amount was 25.593 g. These results provide a useful way for the bio cementation by following the EICP technique to address the issues of environment friendly practice of ground improvement.
Variation of the Temperature and Environmental Humidity in Solid Concrete Slabs for Mezzanine Buildings Using the Species Aptenia cordifolia and Sphagneticola trilobata
Authors: Rodríguez Jose , Vilela Karina
Published: April 2022

The current population is increasing rapidly and as a consequence a greater number of houses is required, which are consolidated through urbanizations; which modify the hydrological processes, alter the energy exchanges between the sun, the surface and the atmosphere, generating changes in the flows and components of the radiation balance that affect the urban heat island. An alternative to control this heat is to promote a green space through green roofs that improve the urban climate. The present research work studies on prototypes of solid concrete slabs the effect of the plant species Aptenia cordifolia and Sphagneticola trilobata on the temperature and environmental humidity in an extensive green roof. The results indicate that both species have a different behavior, being the species Sphagneticola trilobata the one that presents a better behavior before the higher and lower environmental temperature and higher relative humidity; while the Aptenia cordifolia presents it behaves better before the lower relative humidity.
The 6-1/2 Inch Monobore Expandable System for the North Sea Application
Authors: Godfrey Matthew Mark
Published: April 2022

The use of monobore expandable systems has been theorized in previous works (Dean 2003, Dupal 2002) with various proposed embodiments. Commercially available sizes are limited to 8-1/2 and 12-1/4 wherein the size designation refers to the drift diameter which the monobore system may pass through and the post-expanded drift diameter of the monobore liner. In particular, the 12-1/4 in. size has a run history which includes a recent successful commercial installation (Baker 2021). An application within the North Sea where significant pressure gradients are typically encountered during drilling of a 6-1/2 in. section below the 7-3/4 in. base casing was identified as a candidate to leverage existing monobore expandable technology in a 6-1/2 in. size. Monobore expandable technology is the preferred method to manage challenges presented by steep pressure gradients or fluid loss zones while drilling due to the robustness of a solid steel barrier with external isolation seals, which may be cemented in place without a reduction in wellbore diameter. Beginning with the 12-1/4 in. platform and scaling down to a 6-1/2 in. platform created challenges regarding geometry, critical load ratings, and achieving post-expanded system ratings.

A feasibility study was performed which relied heavily on finite element analysis to determine the possibility of the system scale down from 12-1/4 in. to 6-1/2 in. The analysis proved the design of a monobore expandable system in the 6-1/2 in. size based on the requirements for the North Sea application. It also proved that the design would require a non-standard pipe size. The pipe and expansion system were tested in a series of surface level qualification tests and at a test rig within a downhole environment. The results of testing validated the finite element analysis approach to the feasibility study and proved system readiness for field qualification trials.
Using Enhanced Negative Pressure Wave NPW-Based Sensing for Spontaneous Leak Detection in Offshore Risers: A Gulf of Mexico Case Study
Authors: Grimes Matthew , Rensburg Nico Van , Mitchell Stuart
Published: April 2022

This paper describes a novel, IoT-based digital solution for spontaneous leak detection which combines enhanced negative pressure wave (NPW) sensing with advanced signal processing to determine both the presence (∼0.20 - 0.50% of the pipeline cross section) and location of spontaneous leaks in pressurized pipelines within seconds. The solution is appliable to lines carrying any medium (liquid or gas). Possible applications include offshore risers, long-distance transmission lines, gas gathering networks at well sites, and saltwater disposal systems (among others).

The paper provides a description of the solution and outlines the process for its implementation on a jack-up installation in the Gulf of Mexico, where it was used for real-time leak detection on four crude oil risers. The entire system installation and commissioning was completed in one full day offshore. Currently, it is undergoing the "bedding in" process to verify performance. To date, no false positive leak events have been initiated.