bluuebunny/crossref_metadata_2025 huggingface dataset:
Baumartenwechsel in den Walliser Waldföhrenwäldern verstärkt nach grossen Störungen
Authors: Wohlgemuth Thomas , Doublet Violette , Nussbaumer Cynthia , Feichtinger Linda , Rigling Andreas
Published: August 2018

Vegetation shift in Scots pine forests in the Valais accelerated by large disturbances

In the past dozen years, several studies have concluded a vegetation shift from Scots pine to oak (pubescent and sessile) forests in the low elevated zones of the Valais. It is, however, not fully clear in which way such a vegetation shift actually occurs and on which processes such a shift would be based. Two studies, one on the tree demography in the intact Pfynwald and the other on the tree regeneration on the large Leuk forest fire patch, serve to discuss different aspects of the shift from Scots pine to oak. The forest stands of Pfynwald consist of 67% Scots pines and 14% oaks. Regenerating trees are 2–3.5 times more frequent in small gaps than under canopy. In gaps of the Upper Pfynwald, seedlings and saplings of Scots pine are three times more abundant than oaks, while both species regenerate in similar quantities under canopy. In the Lower Pfynwald, young oaks – especially seedlings – are more frequent than Scots pines. A different process is going on at the lower part in the Leuk forest fire patch where Scots pines prevailed before the burn of 2003. While Scots pines regenerate exclusively close to the edge of the intact forest, oaks not only resprout from trunk but also profit from unlimited spreading of their seeds by the Eurasian jay. Regeneration from seeds are hence observed in the whole studied area, independent of the proximity of seed trees. After the large fire disturbance, a mixed forests with a high share of oaks is establishing, which translates to a rapid vegetation shift. The two trajectories are discussed in the light of climate change.
Multi objective optimization on suspension characteristics of vertical axis wind turbine
Authors: Jun Zhu , Dandan Song , QiaoLi Han , Shaolong Li , Jinmei Wang , Guanghuai Li , Di Cao
Published: August 2018

In order to improve the suspension characteristics of passive magnetic bearings in vertical axis wind power generation system, T-shaped group of passive magnetic bearing with three rings which owns high suspension characteristics are proposed. The working principle of the structure is described briefly. The multi-objective optimization is achieved with high bearing capacity and high magnetic stiffness by studying its impacts on the magnetic ring with variable geometric parameters: the height of the magnetic ring, the thickness of the magnetic ring and the air gaps between the magnetic rings. The research shows that suspension characteristics of the novel structure are 2 times of the traditional radial magnetic bearings. Its the bearing capacity is at least 1.75 times before optimization and the magnetic stiffness is at least twice as high as before optimization which provides a reference for the suspension characteristics of the vertical axis wind turbine suspension system.
Forming limit diagrams of AZ31 Mg sheet at elevated temperatures and high strain rates by electromagnetic hybrid forming
Authors: Zou Fangli , Huang Shangyu , Lei Yu , Zhang Jifa , Zhou Mengcheng , Yan Shiwei , Feng Fei
Published: August 2018

Weight reduction is a primary concern in the automotive and electrical industries because of the intensive requirements of energy conservation and emission reduction. As the lightest structural metal, magnesium (Mg) alloys are widely used in the automotive and aerospace industries. However, the current industrial application of this material is mainly limited to pressure casting parts due to its poor formability at room temperature. Therefore, identifying the factors that affect the formability of Mg alloy is highly important. In this study, forming limits of Mg alloy sheet under electromagnetic forming (EMF) condition were analyzed at different temperatures based on the Johnson–Cook constitutive model and the failure model. The complete forming limit diagrams of AZ31 Mg alloy at different temperatures and high strain rates were established. The effects of voltage, capacitance, and temperature on the forming limit of AZ31 Mg alloy under EMF were systematically investigated. Results showed that increased discharge voltage and temperature can effectively improve the EMF limit of Mg alloy. The effect of increasing capacitance on the formability of Mg alloy was not obvious.
Apresentação
Authors: Franco Irley Fernandes , Brandão Renato Matoso
Published: August 2018

Apresentação à OQNFP 42.
Optimalisasi Pengelolaan Asuhan Keperawatan di Instalasi Rawat Jalan Rumah Sakit X
Authors: Zendrato Meylona Verawaty , Sri Hariyati Rr. Tutik
Published: August 2018

ABSTRAKKualitas asuhan keperawatan menjadi elemen kunci mutu pelayanan di rumah sakit. Fenomena yang terjadi di instalasi rawat jalan ialah pemberian asuhan keperawatan yang sangat minim. Tujuan penelitian: mengoptimalkan pengelolaan asuhan keperawatan di instalasi rawat jalan. Metode: Metode yang digunakan studi pilot, identifikasi masalah dengan teknik wawancara terstruktur, observasi, dan pengisian kuesioner kepada 28 perawat. Analisis masalah dilakukan dengan metode fish bone, pemecahan masalah menggunakan metode plan, do, check, action. Hasil: Terjadi peningkatan pengetahuan perawat terhadap proses asuhan keperawatan sebelum (17,80%), sesudah implementasi (82,3%), dan didapati empat faktor yang memengaruhi pemberian asuhan di instalasi rawat jalan, yaitu sumber daya manusia, sistem kerja yang jelas antarbagian, dokumentasi manual di luar keperawatan, dan fasilitas dan sarana yang kurang memadai. Diskusi: pengelolaan asuhan keperawatan membutuhkan dukungan manajemen. Kesimpulan: sebaiknya manajer melakukan perencanaan untuk peningkatan kualitas asuhan keperawatan melalui pengarahan pelayanan kepada visi rumah sakit, peningkatan pendidikan, peningkatan motivasi, dan berkoordinasi dalam pengadaan fasilitas dan sistem layanan guna optimalisasi pengelolaan asuhan keperawatan.Kata kunci: asuhan keperawatan, pengelolaan, rawat jalan.OPTIMIZATION OF NURSING CARE MANAGEMENT AT OUTPATIENT INSTALLATION OF X HOSPITALAbstractThe quality of nursing care is a key element of hospital service quality. A phenomenon that occurs in outpatient care is providing nursing care at the minimum. Objective: To optimize the nursing care management t outpatient installation. Methods: This study employed pilot study, identifying problem using structured interview technique, observation, and filling out questionnaires to 28 nurses. Problems were analyzed using fish bone and solved using plan, do, check, action method. Results: There was an increase in nurses’ knowledge about the process of nursing care before (17.80%) and after the implementation (82.3%), and there were 4 factors that affected the provision of care in outpatient installation, namely human resources, a clear job system between departments, manual documentation beyond nursing, and inadequate facilities and infrastructure. Discussion: Nursing care management requires support from the management. Conclusion: Managers should plan on increasing the quality ofnursing care by directing services to the vision of the hospital, improving education, increasing motivation, and coordinating in the procurement of facilities and service systems in order to optimize the nursing care management.Keywords: nursing care, management, outpatient
Exposure Studies of Different Kinds of Volatile Organic Compounds in Vapour Phase with a Narrow-gap Cell Containing CuxS Modified Carbon Microdisc Electrode
Authors: Kiss László
Published: August 2018

In this article, the feasibility of the CuxS modified carbon microdisc electrode was examined by exposure to four different volatile organic compounds (2-propanol, acetic acid, ethyl acetate and n-butylamine) directly in their vapour phase using cyclic voltammetry and amperometry. The performance of the modified microdisc was compared with the bare carbon microdisc (30 μm in diameter) which was involved in a narrow-gap cell. By using both methods high current increase was observed for 2-propanol with the modified electrode and its sensitivity was sufficiently higher than with the bare electrode. The modified electrode showed lower current signals in case of acetic acid and n-butylamine. The latter formed a condensation layer at the interelectrode gap. Neither the bare nor the modified electrode was sensitive to ethyl acetate.
‘Inexhaustible fertility’: Contemporary Re-figurations of the French Revolution
Authors: Hamilton Paul
Published: August 2018

As Coleridge recognized, the French Revolution was an event especially open to interpretation. The Revolutionary debate supported the increasing importance of hermeneutics as a leading philosophical methodology adequate to explain why the Revolution's meaning was not fixed but tendentious. This was due not only to the variety of its own political narrative, as it ran its course through Girondin, Montagnard, Terroristic, Directorial, and other stages. Commentators such as Friedrich Schlegel argued persuasively that the agenda of the French Revolution pervaded all aspects of life, there to be detected if one had but the wit to see it. Hegel criticized those who tried to arrest this self-historicization of the Revolution for wanting to arrest its natural historical course in initial Jacobin justifications owing too much to Kantian and Fichtean formalism. Following his example, we can find revisions of the significance of the Revolution at work in the thought of European thinkers ranging from Hazlitt to Leopardi, Wollstonecraft to Staël, Barbauld to Keats, Shelley to Constant. This essay examines the character and interactions of some of these typical re-figurings of the French Revolution.
Giambattista Vico's ‘Constructive’ Language and its Post-Revolutionary Readers
Authors: Piperno Martina
Published: August 2018

Reprinted in 1801, Vico's New Science (originally published 1744) had a profound impact on Bourbon Restoration culture, particularly in Italy and France, where it touched post-revolutionary readers profoundly. The reasons for Vico's revival in the early nineteenth century relate closely to the trauma of the political and social changes of that era. Vico's readership seems to have had significant peaks during periods of rapid social transformation: nineteenth-century readers reread the New Science in an attempt to find the reasons for revolutionary failure, and to relate the terror, the sense of displacement, failure and trauma to recognizable laws, promising that, after a crisis, a period of renaissance must necessarily follow. This article analyses the hermeneutic practices of some post-revolutionary readers of Vico (Carlo Cattaneo, Vincenzo Cuoco, Giuseppe Ferrari, Ugo Foscolo, Francesco Lomonaco) and suggests a comparison with the practices of readers during the Second World War (Eric Auerbach, Carlo Levi, Mario Fubini). By doing so, I propose an interpretation of Vico's New Science as a ‘posthumous’ book, acquiring special shades of significance when its readers experience the feeling that nothing will ever be like before, and meditate upon it in isolation, in fear, in exile, upon return from the front, and in prison.
Fatigue Resistance Characterization of Warm Asphalt Rubber by Multiple Approaches
Authors: Yu Jiangmiao , Yu Xianshu , Gao Zheming , Guo Feng , Wang Duanyi , Yu Huayang
Published: August 2018

Warm asphalt rubber (WAR) mixture is a sustainable paving material with advantages including waste recycling and noise reducing. A comprehensive understanding of the fatigue performance of WAR specimens is helpful to its wide application. However, research on evaluating the fatigue performance of WAR binder and mixtures is very limited. This paper applies five fatigue analysis approaches to evaluate the fatigue life of WAR samples with three different warm mix asphalt (WMA) additives. The conventional G*sinδ, linear amplitude sweep (LAS), indirect tensile fatigue test (ITFT), and four-point bending beam (4PB) test were conducted based on available standards. In addition, a novel shear fatigue test was performed on WAR mortars. Test results indicated that the incorporation of crumb rubber has a significantly positive effect on fatigue resistance. WAR with chemical and foaming additives exhibited a poorer performance than asphalt rubber (AR), but their fatigue performance was still greatly superior to the non-rubberized samples. Finally, LAS as well as mortar shear fatigue and 4PB tests provided the same prediction of fatigue resistance, while the results of G*sinδ and the ITFT were inconsistent. It is recommended to use LAS, the mortar shear fatigue test, and the 4PB test for the fatigue resistance evaluation of rubberized specimens. The validation of the findings with more materials and field performances is recommended.
Smart Solar-Powered LED Outdoor Lighting System Based on the Energy Storage Level in Batteries
Authors: Kiwan Suhil , Abo Mosali Anwar , Al-Ghasem Adnan
Published: August 2018

A novel smart solar-powered light emitting diode (LED) outdoor lighting system is designed, built, and tested. A newly designed controller, that continuously monitors the energy status in the battery and, accordingly, controls the level of illumination of the LED light to satisfy the lighting requirements and/or to keep the light “on” the longest time possible, has been developed. The use of such a reliable solar energy-driven lighting system, with maximum time when the light is “on”, will eliminate the sudden-death of light problem present in conventional photovoltaic (PV) outdoor lights and, therefore, will enhance the natural surveillance and feeling of safety in sustainable buildings and cities. Furthermore, the new smart control eliminates the overdischarge of the system battery and, thus, ensures a longer lifetime of the system battery. Experimental measurements on a system using a 30 W LED light showed that the operating hours of the new system reached 29.16 h (1750 min), while the operating hours for a similar conventional system were 20.86 h (1252 min). Thus, the new lighting system was demonstrated, securing more than 40% of operating hours than the conventional systems.
NF-κB, Mesenchymal Differentiation and Glioblastoma
Authors: Yamini Bakhtiar
Published: August 2018

Although glioblastoma (GBM) has always been recognized as a heterogeneous tumor, the advent of largescale molecular analysis has enabled robust categorization of this malignancy into several specific subgroups. Among the subtypes designated by expression profiling, mesenchymal tumors have been associated with an inflammatory microenvironment, increased angiogenesis, and resistance to therapy. Nuclear factor-κB (NF-κB) is a ubiquitous transcription factor that plays a prominent role in mediating many of the central features associated with mesenchymal differentiation. This review summarizes the mechanisms by which NF-κB proteins and their co-regulating partners induce the transcriptional network that underlies the mesenchymal phenotype. Moreover, both the intrinsic changes within mesenchymal GBM cells and the microenvironmental factors that modify the overall NF-κB response are detailed.
Confident Parents for Easier Children: A Parental Self-Efficacy Program to Improve Young Children’s Behavior
Authors: Mouton Bénédicte , Loop Laurie , Stiévenart Marie , Roskam Isabelle
Published: August 2018

This study presents the effects on children’s behavior of Confident Parents, a focused parenting program targeting parental self-efficacy. This parenting program aims to improve child behavior through the enhancement of parental self-efficacy. Confident Parents was experimentally tested on a total sample of 80 parents of three-to-six-year-old preschool aged children with moderate to clinical levels of externalizing behavior. Thirty-seven parents participated in the program, and were compared with a waitlist control group (n = 43). The intervention consisted of eight weekly group sessions. Effect sizes were evaluated through both observational and parent-report measures on the child’s behavior, as well as self-reported parental self-efficacy at pretest, post-test, and a four-month follow-up. Through a multi-level analysis, predictors of the change in the child’s behavior were identified. The moderating effect of socio-economic risk and externalizing behavior at baseline were also included in the analysis. Results show that Confident Parents improved the child’s behavior, both reported by parents and, to a lesser extent, when observed in interaction with the parent. Children with higher levels of behavior difficulty benefited more while those with socio-economic risk benefited less from this program. These results illustrate that focusing a parenting program on improving self-efficacy is effective to reduce externalizing behavior in children. This underdeveloped treatment target is worthy of investigation in parenting intervention research.
Experimental Investigation of Crack Propagation and Strain Fields Evolution around a Crack Tip in 5A05 Aluminum Alloy
Authors: Li Jijun , Li Wencai , Zhao Chunwang , Xing Yongming , Lang Fengchao , Hou Xiaohu
Published: August 2018

In situ scanning electron microscopy three-point bending test was employed in this study to investigate the crack initiation and propagation in 5A05 aluminum alloy. The microscale strain fields around the crack tip were measured by using the geometric phase analysis method. Results show that prior to the crack initiation, the normal strain εyy (y direction is perpendicular to the load direction) was tensile around the notch, whereas the normal strain εxx (x direction is parallel to the load direction) was compressive around the notch. The shear strain εxy was nearly zero. With the increase in load, the normal strains εyy and εxx gradually increased, but the change in shear strain εxy was not evident. When the stresses at several sharp points at the notch root reached the breaking strengths, a few microcracks initiated at these points. At this moment, the normal strains εyy and εxx were much greater than the shear εxy, and dominated the strain fields around the crack tip. In the crack propagation process, the normal strains εyy and εxx, and the shear strain εxy dominated the strain fields around the crack tip, thereby leading to a Z-form of crack propagation path in the specimen.
Selection of Parameters and Strategies to Reduce Energy Consumption and Improve Surface Quality in EN-AW 7075 Molds Machining
Authors: Rodriguez-Alabanda Oscar , Bonilla Maria Trinidad , Guerrero-Vaca Guillermo , Romero Pablo Eduardo
Published: August 2018

The machining of cavities for blow molding is a long and costly process, with the objective of obtaining an excellent surface finish with the minimal possible electrical energy consumption (EEC). This work has studied which combination of cutting parameters and cutting strategies to use to achieve an optimum surface finish on the mold using the minimal associated EEC: in roughing operation, tool path strategy and axial depth of cut were studied; in finishing operation, tool path strategy, spindle-speed, feed-rate, and step-over were evaluated. Thirty-two molds were machined in blocks of aluminium alloy EN-AW 7075 T6 in a machining center of a three-axis, following an orthogonal design of experiments. The analysis of results demonstrates that: a roughing strategy has influence on the surface roughness on the bottom of the mold; a finishing strategy is an influential factor on the surface roughness on the walls of the mold; certain parameters have no relevance on the surface roughness but have an influence on the EEC; an adequate selection of cutting strategies and cutting parameters permit an improvement of surface roughness of up to 70%, and a reduction of 40% in EEC, compared to the less favorable tests.
Biomedical Applications of Silver Nanoparticles: An Up-to-Date Overview
Authors: Burdușel Alexandra-Cristina , Gherasim Oana , Grumezescu Alexandru Mihai , Mogoantă Laurențiu , Ficai Anton , Andronescu Ecaterina
Published: August 2018

During the past few years, silver nanoparticles (AgNPs) became one of the most investigated and explored nanotechnology-derived nanostructures, given the fact that nanosilver-based materials proved to have interesting, challenging, and promising characteristics suitable for various biomedical applications. Among modern biomedical potential of AgNPs, tremendous interest is oriented toward the therapeutically enhanced personalized healthcare practice. AgNPs proved to have genuine features and impressive potential for the development of novel antimicrobial agents, drug-delivery formulations, detection and diagnosis platforms, biomaterial and medical device coatings, tissue restoration and regeneration materials, complex healthcare condition strategies, and performance-enhanced therapeutic alternatives. Given the impressive biomedical-related potential applications of AgNPs, impressive efforts were undertaken on understanding the intricate mechanisms of their biological interactions and possible toxic effects. Within this review, we focused on the latest data regarding the biomedical use of AgNP-based nanostructures, including aspects related to their potential toxicity, unique physiochemical properties, and biofunctional behaviors, discussing herein the intrinsic anti-inflammatory, antibacterial, antiviral, and antifungal activities of silver-based nanostructures.
Simulations and Laboratory Tests for Assessing Phosphorus Recovery Efficiency from Sewage Sludge
Authors: Daneshgar Saba , Buttafava Armando , Callegari Arianna , Capodaglio Andrea G.
Published: August 2018

Phosphorus is a potential environmental pollutant, which could lead to the eutrophication of water bodies. For this reason, wastewater treatment plants worldwide are often designed and operated to eliminate phosphorous from effluents, at substantial cost. At the same time, phosphorus is an essential nutrient for agriculture and, consequently, human life. Data seem to suggest that the world will run out of phosphorus by around 2300, in the best case scenario, although even shorter estimates exist. This situation evokes the need for more efficient phosphorus recovery technologies, in order to meet current water quality requirements and—at the same time—critical future phosphorous needs. Chemical precipitation is the main process for achieving a phosphorus-containing mineral suitable for reuse as a fertilizer, where Struvite is an example of such a product. In this study chemical equilibrium of struvite precipitation was simulated using US Geological Survey (USGS)’ PHREEQC model, and results were compared to laboratory precipitation tests to evaluate struvite recovery efficiency under various conditions. pH had the most significant effect on the results and P recovery of >90% was achieved at pH = 9.5. Simulations indicated that struvite precipitation is affected by the presence of Amorphous Calcium Phosphate (ACP) and calcite in the final product of the process. The model showed great potential for predicting equilibrium conditions, and could be very helpful for future optimization of the process.
Spatial–Temporal Evolution and Factor Decomposition for Ecological Pressure of Carbon Footprint in the One Belt and One Road
Authors: Sun Qipeng , Geng Yafang , Ma Fei , Wang Chao , Wang Bo , Wang Xiu , Wang Wenlin
Published: August 2018

Low-carbon and green development is important to promote the sustainable economic and social development of countries along the One Belt and One Road. These countries have distinct differences in their ability to withstand carbon emission pressures and their driving factors, due to different stages of development and economic characteristics. This paper presents a model of ecological pressure of the carbon footprint in energy consumption (EPcfec), defined by three states: light, balanced, and heavy pressure. The EPcfec was calculated from data on 56 countries along the One Belt and One Road from 1994–2014, and analysis of the data’s temporal and spatial evolutionary rules was conducted. Furthermore, we used the LMDI method to extract the driving forces of EPcfec and evaluated the contribution of these factors to the overall region and seven sub-regions. The results showed that EPcfec growth slowed over time, with the value of EPcfec reaching 3190.51 in 2014. Resource-rich countries have a greater value of EPcfec and are mainly distributed in parts of West Asia, North Africa, and Southeast Asia. The per capita export of goods and services, and the population density on productive land contribute to ecological pressure on the carbon footprint. Energy structure, the influence of international trade on GDP, and energy intensity exerted an inhibitory effect on the ecological pressure of the carbon footprint. This paper proposes mitigation measures for optimizing energy structure, improving energy efficiency, developing low energy consumption, and promoting green international trade. Our results provide support for countries along the One Belt and One Road to mitigate ecological pressures resulting from their carbon footprint.
How Does Tourism Penetration Affect House Prices? Evidence From Crete, Greece
Authors: Kavarnou Dimitra , Nanda Anupam
Published: August 2018

This study examined the relationship between tourism penetration and house prices. We used a very touristic place, Crete, which is a major Greek island, as a case study to test research hypotheses. With data from 2006 to 2012, we constructed tourism indicators for the four prefectures
of Crete. Then by using principal component analysis (PCA) we created a tourism penetration rate (TPR) for each prefecture and ranked them in terms of tourism penetration. In the second stage of the analysis, we performed a hedonic house price regression analysis. We established empirical
findings that (i) the TPR of a prefecture has a significant effect on house prices of the prefecture and (ii) house prices are affected by the TPR of the neighboring prefectures, indicating statistically significant tourism spillover effects. The findings, although significant, show asymmetric
effects that confirm both the impact of tourism penetration on house prices and the presence of spillover effects across Crete Island. Models were tested for robustness across several specifications. The analytical framework drawing from tourism and housing economics literature is repeatable across regions with a significant tourism sector.
Role of Hostels in Fostering Intercultural Competence Among Host Communities
Authors: Lam Joanne , Singh Neha
Published: August 2018

The tourism industry is one of the world's largest industries, contributing over $7.6 trillion in 2016, according to Statista (https://www.statista.com/topics/962/global-tourism/). It is also frequently highlighted as a possible agent in promoting peace, as well as improving
cross-cultural understanding. In particular, tourist accommodations can allow for such opportunities. This research analyzes how hostelling, in particular, Hostelling International Santa Monica, serves as an avenue to foster intercultural competence for host communities. This study uses a
combination of grounded theory and ethnographic research methods to conceptualize a process model of fostering intercultural competence. Conceptualizing the hostel as an intercultural space, this research identifies the importance of purposeful facilitation to foster engagement, self-reflection,
and behavioral transformation for improved intercultural competence. This study illustrates hostels as an embassy to improving cross-cultural understanding. It recognizes the potential for hostelling to foster diverse understanding and cultivate intercultural competence. It also serves to
solidify Hostelling International USA's contribution to broadening cultural exchanges, encouraging intercultural dialogue and educating for peace.
Slowing Down Type II Migration of Gas Giants to Match Observational Data
Authors: Ida Shigeru , Tanaka Hidekazu , Johansen Anders , Kanagawa Kazuhiro D. , Tanigawa Takayuki
Published: August 2018

The mass and semimajor axis distribution of gas giants in exoplanetary systems obtained by radial velocity surveys shows that super-Jupiter-mass planets are piled up at ≳1 au, while Jupiter/sub-Jupiter-mass planets are broadly distributed from ∼0.03 au to beyond 1 au. This feature has not been explained by theoretical predictions. In order to reconcile this inconsistency, we investigate evolution of gas giants with a new type II migration formula by Kanagawa et al., by comparing the migration, growth timescales of gas giants, and disk lifetime, and by population synthesis simulation. While the classical migration model assumes that a gas giant opens up a clear gap in the protoplanetary disk and the planet migration is tied to the disk gas accretion, recent high-resolution simulations show that the migration of gap-opening planets is decoupled from the disk gas accretion and Kanagawa et al. proposed that type II migration speed is nothing other than type I migration speed with the reduced disk gas surface density in the gap. We show that with this new formula, type II migration is significantly reduced for super-Jupiter-mass planets, if the disk accretion is driven by the disk wind as suggested by recent magnetohydrodynamic simulations. Population synthesis simulations show that super-Jupiter-mass planets remain at ≳1 au without any additional ingredient such as disk photoevaporation. Therefore, the mystery of the pile-up of gas giants at ≳1 au will be theoretically solved if the new formula is confirmed and wind-driven disk accretion dominates.
Tuning the Electronic Properties of Symetrical and Asymetrical Boron Nitride Passivated Graphene Nanoribbons: Density Function Theory
Authors: Bashirpour Mohammad , Kefayati Ali , Kolahdouz Mohammadreza , Aghababa Hossein
Published: August 2018

—Density function theory (DFT) based simulation combined with non-equilibrium green function (NEGF) was used to theoretically investigate electrical properties of symmetrical and asymmetrical boron nitride (BN) passivated graphene nanoribbons. Using density function theory method, it is demonstrated that the band gap of armchair (A) graphene nanoribbon (GNR) can be widened with boron nitride passivation. five symmetrical and five asymmetrical structures were considered, for which we obtained band gaps from 0.45 eV to 2 eV for symmetrical structures and 0.3 eV to 1.5 eV for asymmetrical structures. For the same width of graphene nanoribbon, our results showed that asymmetrical structure has a smaller band gap and almost the same conductance in comparison with the symmetrical one. Finally, comparison between the asymmetrical structure and the hydrogenated armchair graphene (h-AGNR) nanoribbon showed that, hBN-AGNR exhibited a higher conductance compared to an h-AGNR for the same width of GNR.
Synthesis of Novel Geopolymer Supported Nano Bimetallic Catalysts and its Application for Isopropanol Dehydrogenation
Authors: Satmon John , Hu Zheng Feng , Zhu Ming Qiao
Published: August 2018

A novel geopolymer supported nanobimetallic catalyst for isopropanol dehydrogenation was prepared by modified wet impregnation and reduction method. XRD, SEM, EDX and TEM analysis confirmed formation of amorphous geopolymer from the polymerization of metakaolin and deposition of nanometals over the geopolymer support. The bimetallic catalyst containing 5wt. % Cu and 10wt. % Ni loading over geopolymer shows an excellent performance with 23.18% conversion of isopropanol and 88.24% selectivity to acetone under reaction conditions of 90 °C, 3 hours, and catalyst amount of 0.15g/5.0g of isopropanol. Moreover, the catalyst maintains its catalytic stability without noticeable loss of activity after five cycles.
The Use of Factorial Design to Improve a Harmony Search Algorithm to Synthesize Heat-Integrated Distillation Sequences
Authors: Sukpancharoen Somboon , Srinophakun Thongchai Rohitatisha , Hirunlabh Jongjit , Rattanachoung Nopporn
Published: August 2018

Optimization problems often involve a large number of design variables, and the exact influence of each of these variables upon the objective function can become rather complex; there may exist local optima for the objective function, but for the typical heat-integrated distillation sequence, the matter of interest is solely the global optimum. Therefore, it is necessary to create a stochastic algorithm method which can synthesize distillation systems with multiple components. The encoding process employs and integer number series which allows the system flow sheet structure to be portrayed and then managed. Within this portrayal, the broad synthesis problem takes the form of an implicit MILP (mixed-integer linear programming) problem. This study considers the attributes of six well-known optimization algorithms: Harmony Search algorithm (HS), Artificial Bee Colony (ABC), Bat Algorithm (BA), Crow Search Optimization (CSO), Grew Wolf Optimization (GWO) and Monarch Butterfly Optimization (MBO). The optimal variables which influence the harmony search algorithm can be determined through full factorial design analysis. These variables can then be employed in the search to discover the optimal heat-integrated distillation sequence. The study investigates the attributes of the optimal configuration solution, in terms of harmony size (HS), required number of iterations, harmony memory considering the rate (HMCR), and pitch adjustment rate (PAR). The study then adopts the HS algorithm which is duly improved in order to address the problem. In comparison with alternative techniques, HS is more effective and more robust than other approaches.
Empirical Model of Operating Temperature and Pressure Effect towards Pure and Binary O2/ N2 Gas Permeability in Polysulfone Membrane
Authors: Lock Serene Sow Mun , Lau Kok Keong , Lock Irene Sow Mei , Shariff Azmi Mohd , Yeong Yin Fong , Ahmad Faizan
Published: August 2018

Oxygen (O2) enriched air combustion via adaption of polymeric membranes has been proposed to be a feasible alternative to increase combustion proficiency while minimizing the emission of greenhouse gases into the atmosphere. Nonetheless, majority of techno-economic assessment on the O2 enriched combustion evolving membrane separation process are confined to assumption of constant membrane permeance. In reality, it is well known that membrane permeance is highly dependent upon the temperature and pressure to which it is operated. Therefore, in this work, an empirical model, which includes the effect of temperature and pressure to permeance, has been evaluated based on own experimental work using polysulfone membrane. The empirical model has been further validated with published experimental results. It is found that the model is able to provide an excellent characterization of the membrane permeance across a wide range of operating conditions for both pure and binary gas with determination coefficient of minimally 0.99.
Simulation of CO2 Adsorption to Enhance Adsorbent Material Efficiency
Authors: Sangsuradet Supawon , Worathanakul Patcharin
Published: August 2018

Computer simulation techniques have gained many attentions. The objective of this research was to study influence of the exchangeable cations of Group 1A (Li+, Na+, K+, Rb+, Cs+) on the CO2adsorption in the system using Grand Canonical Monte Carlo (GCMC) simulation. In this simulation, zeolite is a simulation box. The interaction potential simulation with Lennnard-Jones potential showed that Li+and CO2had the greatest molecular attraction with Li+having the highest number of CO2molecules in the simulation box. The number of CO2/molecules in the simulation box are as followed with Li+> Na+> K+> Rb+> Cs+.
The Culturing Optimization of Bioleaching of the Lead-Zinc Tailings from Different Depths
Authors: Cui Xing Lan , Yang Fei Hua , Gu Qi Yuan , Guo Rong , Tian Zhi Yu , Ning Yuan , Yan Xiao
Published: August 2018

This study was a continuation of previous work designed to further explore the effect of different culture condition on the recovery of the valuable metals by bacteria. The experiment focused on the Nandan lead-zinc tailings from different depths. First of all, the study systematically performed multi-elements analysis. Subsequently, the effect of the temperature and agitation speed on the bacterial growth was investigated. The data revealed that the temperature of 35°C and the agitation of 160 rpm were the optimum culture conditions for the bacteria. Finally, the bioleaching experiments were performed to explore the ability of bioleaching the tailings. The study illustrated that the microorganism was able to effectively extract valuable metals from different depths samples.
Forming Limit Analysis of Molybdenum Reinforced Carbon Steels
Authors: Rajeshkannan Ananthanarayanan , Narayan Sumesh
Published: August 2018

The occurrence of ductile fracture during the plastic deformation of powder metallurgy materials is adverse and damaging and the prediction of fracture is very important in the early stages as early modifications will prevent failure. This will tend to save a lot of money and forming limit studies in many metal forming processes is up most important. Forming limit analysis on the cold forged molybdenum reinforced carbon steels were carried out in this work. In this study two key strain hardening parameters are used to study the formability characteristics. This analysis is effectively used for design of powder metallurgy parts and most importantly the die design as repressing needs to be employed before pores appear as cracks on the free surface. The cold forging was carried out on Fe-0.8%C, Fe-0.8%C-1%Mo, Fe-0.8%C-1.5%Mo and Fe-0.8%C-2.0%Mo and the formability behavior of the same is presented.
Laser Micromachining of Titanium Alloy in Water with Different Temperatures
Authors: Wuttisarn Taweeporn , Tangwarodomnukun Viboon , Dumkum Chaiya
Published: August 2018

Underwater laser machining process has been employed as an alternative process to ablate materials with minimum thermal damage. Though many studies provide comprehensive investigations to enable the understanding of laser-water-material interactions during the laser ablation process in water, the effect of water temperature on the ablation performance has not been revealed yet. To cope with this challenge, this paper presents the roles of water temperature on cut dimensions in the underwater laser micromachining of titanium alloy (Ti-6Al-4V). The effects of laser power, traverse speed and number of laser passes were also examined in this study, where groove width and depth were measured and analyzed. The experimental results showed that a deep cut can be produced by using slow traverse speed with multiple-pass technique. However, using too high laser power can cause a shallow cut due to the large formation of recast in the laser-ablated area. According to the findings of this study, the laser energy density of about 750 J/mm2can provide the deepest cut among the other conditions examined in this study.
Compression Test of Glass Fiber-Reinforced Ice
Authors: Ohashi Takahiro , Hayashi Ryu , Nanba Hidetoshi
Published: August 2018

Lead or low temperature melting alloys have been sucessfuly utilized as a filling medium in tube forming processes, such as bending and bulging; however, strict lead-free-control plan in industries have prohibited the use of lead in recent years. The authors suggest the use of fiber-reinforced ice (FRI) as an alternative. Fiber of recycled paper was utilized for the preparation of FRIs, and the results of compression tests revealed that the fabricated FRIs exhibit sufficient crushing-strength suitable for use as an alternative for lead-filled media. However, the high density of the fiber in the mixture of fiber and water makes it difficult to fill a tube with the fiber in the pre-freezing process owing to its high vscosity. Therefore, it is useful to examine other strong fibers for FRIs to reduce the ratio of the fiber. In this study, the authors examined glass fibers as reinforcement in FRIs. Compression tests were conducted at various crosshead speeds, and the difference in the stress-strain behaviors of the FRIs with glass fiber and paper-pulp fiber was analyzed.
Study on Horizontal TIG Welding Process of 1Cr18Ni9Ti Stainless Steel Tube
Authors: Hu Min
Published: August 2018

To improve the welding performance and guarantee the quality of welds, this paper mainly starts with reasonably selecting welding materials before welding, choosing appropriate welding process parameters, paying full attention to the welding operation skills of positioning welding, base coating, filling and cap welding, to study horizontal TIG welding process of 1Cr18Ni9Ti stainless steel tube, and prevent the generation of hot crack defects.
Mechanical Properties and Thermal Conductivity of Lightweight Clay Bricks Fabricated with a Powdered Marble Dust Additive
Authors: Janbuala Sutas , Eambua Mana , Satayavibul Arpapan , Nethan Watcharakhon
Published: August 2018

The objective of this study was to recycle powdered marble dust to improve mechanical properties and thermal conductivity of lightweight clay bricks. Varying amounts of powdered marble dust (10, 20, 30, and 40 vol.%) were added to a lightweight clay brick at the firing temperatures of 900, 1000, and 1100 °C. When higher quantities of powdered marble dust were added, the values of porosity and water absorption increased while those of thermal conductivity and bulk density decreased. The decrease in apparent porosity and water absorption were also affected by the increase in firing temperature. The most desirable properties of the clay bricks were obtained for the powdered marble dust content of 40 vol.% and firing temperature 900 °C: bulk density of 1.20 g/cm3, compressive strength 9.2 MPa, thermal conductivity 0.32 W/m.K, and water absorption 22.5%.
Influence of Replacement Rate of Fine Aggregate by Blast Furnace Slag Sand on Fresh Properties of Mortar
Authors: Takehisa Daiki , Takahashi Naoki , Hashimoto Shin Ichiro , Date Shigeyuki
Published: August 2018

For enlarging and promoting usage of blast furnace slag sand and improving construction performance of concrete with it, the behavior of the mortar under both static and dynamic, using vibrator, conditions were confirmed from the viewpoint of plastic viscosity, filling property and bleeding rate. As the results, within the scope of this experiment, by investigating the mixing ratio at which the plastic viscosity changes from the vibration plasticity viscosity obtained by the feather penetration type viscosity measurement test, it was considered that the appropriate fine aggregate mixing ratio can be estimated. Furthermore, the pore water pressure was measured for a sample in which the mixing ratio of the fine aggregate was changed, and the possibility of evaluating the fresh properties from the tendency of disappearance of pore water pressure after stopping the vibration was indicated.
Cross Laminated Timber in the International Context and in Brazil: Most Relevant Aspects
Authors: Ramos Fernando Murilo Gontijo , Carrasco E.V.M. , Rodrigues Francisco Carlos
Published: August 2018

Timber is still being rediscovered as building material of excellence in Brazil, and especially as one of the most environmentally friendly one. In the scenario of the production of sustainable buildings, the construction system that uses wood panels - widely used in Europe, USA and Canada - called Glued Laminated Timber (GLULAM) and Cross Laminated Timber (CLT), occupies a prominent place, especially by the possibility of using wood from planted forests. This work aims to provide an overview of what is being produced in Europe and in Brazil.
Toughened Poly(Trimethylene Terephthalate) by Reactive Blending with PTW
Authors: Wang Kun Yan
Published: August 2018

New toughened poly (trimethylene terephthalate) (PTT) materials were obtained by reactive blending with poly (ethylene-butylacrylate-glycidyl methacrylate) (PTW). Morphology observation showed the well-dispersed domains of PTW in PTT matrix. The notched impact strength of the blends with 30wt% PTW is obviously higher than that of pure PTT. PTT-g-PTW copolymer as compatibilizer was formed by the interfacial reaction between the end epoxy group of PTW and the carboxylic or hydroxyl groups at the chain ends of PTT in the blends. Large number of stretched polymeric fibrils are uniformly distributed on the Izod impact fractured surface, which leads to an improvement in fracture toughness due to the consumption of fracture energy.
Peroxide Induced Reaction as a Cross-Linking Method in PHBV Biomaterial Gate Dielectrics
Authors: Wang Kun Yan
Published: August 2018

A peroxide induced reaction was applied as a cross-linking method for Poly (3-hydroxybutyrate-co-3-hydroxyvalerate) (PHBV) biomaterial gate dielectrics. PHBV was effectively cross-linked with a peroxide inducer at a relatively low temperature (90°C). The cross-linked microstructures improve the thermal stability compared with uncross-linked PHBV. This peroxide induced cross-linking method was compatible with plastic substrates for flexible electronic applications. The cross-linked PHBV thin films displayed smooth surfaces.
Experience of Development of Epoxy Composites Appendix of Methods of Rank Correlation
Authors: Garkina Irina , Danilov Alexander
Published: August 2018

The uniform concept of synthesis of construction materials with special properties as multicriteria difficult technical system with use of an iterative way is offered. Composite materials with complex hierarchical structure are considered as a set of typical elements and communications between them (multilevel structures). Transition from one level to another is offered to be carried out on the basis of allocation of substructures (the macroscopic elements interconnected in the easy and clear way). On the basis of experimental data assessment of statistical communication between 14 properties of materials for various 10 structures is defined. The annex of methods of rank correlation to synthesis of epoxy composites on their properties on the basis of the analysis of statistical data is given.
Preparation of Lightweight Mullite-Anorthite Refractories by Different Routes
Authors: Zhang Dan Yang , Qu Ling , Yuan Wen Jie
Published: August 2018

Mullite-anorthite as a kind of lightweight refractory combines the low thermal conductivity of anorthite and the excellent thermal properties of mullite. In this work, mullite beads and calcium aluminate cement was used as the main component and bonding agent. The lightweight mullite-anorthite refractory was prepared by difference routes including foaming method, addition of pore-forming agent and sacrificial template method. The phase composition, bulk density, apparent porosity and thermal conductivity of samples were compared. The results showed that anorthite formed as the consequence of the reaction of cement and mullite. Extra addition of foam, cornstarch and polyurethane sponge could decrease the bulk density of samples. The pore size of samples prepared by foaming method was the smallest. The apparent porosity of samples obtained by sacrificial template method was largest, but the thermal conductivity was the highest due to the open pores.
The Effects of Carbon Content on ZrCO Microspheres Prepared by Internal Gelation Process with Carbon Black
Authors: Sun Xi , Ma Jing Tao , Zhao Xing Yu , Hao Shao Chang , Deng Chang Sheng , Li Zi Qiang , Liu Bing
Published: August 2018

ZrCO ceramic microspheres were fabricated by sol-gel combined with carbothermic reduction. The effect of carbon on the physicochemical characteristics of the microspheres was investigated. The results indicated that with the increase of carbon content in the broth, the interior structure of the sintered microspheres would become loose, which led to the lowering of the density and the decreasing of crush strength of the ZrCO microspheres. Crack-free ZrCO ceramic microspheres with the high mass fraction of ZrC could be successfully obtained with C/Zr = 3 in the broth sintered at 1550°C for 4h in argon containing 5%CO.