bluuebunny/crossref_metadata_2025 huggingface dataset:
Poly(Lactic Acid)-Based Nanobiocomposites with Modulated Degradation Rates
Authors: Valentina Iozzino , Haroutioun Askanian , Fabrice Leroux , Vincent Verney , Roberto Pantani
Published: October 2018

In the field of biodegradable polymers such as poly(Lactic Acid) (PLA), it is quite well known that their kinetics of hydrolysis strongly depend on the pH of the hydrolyzing medium. The idea explored during this study focused on PLA, is the addition of additives that are able to control the pH of water when it diffuses inside the polymer. For instance, acids (i.e. succinic acid, also used as food additive) are bio- and eco- friendly additives that are able to play this role. In order to control the release of these molecules and their dispersion inside the polymer, their intercalation in biocompatible nanofillers like layered double hydroxides (LDH) is here considered. The additives have been dispersed in the polymer by melt compounding, commonly used in the plastic industry. Several composites of PLA (4032D) and LDH intercalated with organic acids (succinic, fumaric, and ascorbic acid) have been obtained by an extrusion process. From all extruded materials, PLA films obtained by compression molding were then subjected to hydrolysis tests. The results showed that the mentioned molecules, dispersed in the polymer, are able to control the rate of hydrolysis, and experimental results show an increase of degradation time for samples containing LDH-organic acid (in particular with LDH-succinic acid), making such hybrid additives an appropriate and efficient solution for PLA.
Transparent Photocatalytic Thin Films on Flexible Polymer Substrates
Authors: Vodišek Nives , Šuligoj Andraž , Korte Dorota , Lavrenčič Štangar Urška
Published: October 2018

Self-cleaning and/or photocatalytic films on polymer substrates have found numerous applications during the past decades. However, the common demand for high-temperature post synthesis treatment limits the application to temperature resistant substrates only. Herein, we prepared self-cleaning photocatalytic films on four thermosensitive polymeric substrates: polyvinyl chloride (PVC), polymethyl methacrylate (PMMA), and acryl coated polyester (PES) fabric (D2) with poly(vinylidene fluoride) (PVDF) containing lacquer (D1). TiO2 was prepared via a low-temperature sol-gel process using titanium(IV) isopropoxide and zirconium(IV) butoxide as precursors with various loading levels of Zr; 0, 5, 10, and 20 mol.%, and deposited on the substrates by using a SiO2 binder in form of thin films (ca. 200 nm thick) via dip-coating. The films were characterized by SEM, hardness test, UV-Vis, photothermal beam deflection spectroscopy, and IR spectroscopy, while photocatalytic activity was measured by the fluorescence-based method of the terephthalic acid probe and wetting by contact angle measurements. Films containing 10 mol.% of Zr showed the best compromise regarding photocatalytic activity and mechanical stability while from substrates point of view PVC performed the best, followed by PMMA, D1, and D2. The beneficial role of SiO2 binder was not only guaranteeing excellent mechanical stability, but also to prevent the D1 polymer from deterioration; the latter was found to be labile to long-term solar-light exposure due to degradation of the top PVDF layer.
Boosted Visible-Light Photodegradation of Methylene Blue by V and Co Co-Doped TiO2
Authors: Lv Tianping , Zhao Jianhong , Chen Mingpeng , Shen Kaiyuan , Zhang Dongming , Zhang Jin , Zhang Genlin , Liu Qingju
Published: October 2018

In this work, TiO2 photocatalysts, co-doped with transition metal ions vanadium (V) and cobalt (Co) ((V,Co)–TiO2), were synthesized by the sol–gel method. The synthesized photocatalysts were characterized by X-ray diffraction (XRD), transmission electron microscopy (TEM), X-ray photoelectron spectroscopy (XPS), nitrogen adsorption and desorption measurement, UV-Vis absorption and photoluminescence spectrum (PL) spectra. The results show that V and Co co-doping has significant effects on sample average crystalline grain size, absorption spectrum, recombination efficiency of photo-induced electron-hole pairs (EHPs), and photocatalytic degradation efficiency of methylene blue (MB). (V,Co)–TiO2 photocatalyst exhibits an obvious red shift of the absorption edge to 475 nm. Photocatalytic degradation rate of (V,Co)–TiO2 sample for MB in 60 min is 92.12% under a Xe lamp with a cut-off filter (λ > 400 nm), which is significantly higher than 56.55% of P25 under the same conditions. The first principles calculation results show that V and Co ions doping introduces several impurity energy levels, which can modulate the location of the valence band and conduction band. An obvious lattice distortion is produced in the meantime, resulting in the decrease in photo-generated EHP recombination. Thus, (V,Co)–TiO2 photocatalyst performance is significantly improved.
Er-Doped Nanostructured BaTiO3 for NIR to Visible Upconversion
Authors: Meneses-Franco Ariel , Campos-Vallette Marcelo , Vásquez Sergio Octavio , Soto-Bustamante Eduardo A.
Published: October 2018

Photoluminescent mechanisms in erbium-doped barium titanate nanoparticle systems were studied. Er3+ ions were introduced into the BaTiO3 lattice by the sol-gel method. The resulting Er3+ concentration was between 0% and 5%, with Ba/Ti ratios of 1.008 and 0.993. The stoichiometry of Ba and Ti concentrations in the lattice influenced the doping mechanism and placement of erbium ions in the lattice structure. Our research shows the existence of a strong correlation between Ba/Ti ratios, erbium concentration, phase structure and doping site location on the upconversion photoluminescence mechanisms. Competing upconversion emissions 2H11/2/4S3/2→4I15/2 at 523 and 548 nm respectively and other photoluminescent mechanisms as 4I9/2→4I11/2 around 4000 nm (2500 cm−1) were studied using Raman and emission spectroscopy. The upconversion process is predominant over other photoluminescent decay when the material presents high distortion in the surrounding activator.
Atomistic Investigation on Diffusion Welding between Stainless Steel and Pure Ni Based on Molecular Dynamics Simulation
Authors: Zhang Yanqiu , Jiang Shuyong
Published: October 2018

Based on molecular dynamics (MD) simulation, the behaviors and mechanisms of diffusion welding between 304 stainless steel (304 SS) and pure Ni were investigated in the present study. The results show that surface roughness has a significant influence on the diffusion behaviors of atoms during diffusion welding between two different materials, and it is suggested that the rough surface should be set on the pure Ni rather than the 304 SS during the diffusion welding between them. Temperature plays an important role in the interface diffusion. With the increase of temperature, the number of atoms diffusing into the opposite side increases and the diffusion distances increase as well. As a consequence, the diffusion welding should be performed at a suitably elevated temperature. The influence of vertical pressure on the diffusion bonding between the two materials includes two aspects. One is to increase the contact area via deforming the asperities or grooves at the interface, which provides more opportunities for the diffusion between the two materials. The other is to reduce the mobility of atoms within a lattice. As a consequence, the pressure effect is smaller than temperature effect during diffusion welding between 304 SS and pure Ni.
The Influence of Mayenite Employed as a Functional Component on Hydration Properties of Ordinary Portland Cement
Authors: He Zhen , Li Yang
Published: October 2018

Influence of C12A7 (12CaO·7Al2O3) as a functional component on hydration properties of Ordinary Portland Cement is studied using isothermal microcalorimetric technique, X-ray diffraction analysis, and thermodynamic calculation. Meanwhile, hydrate assemblages are simulated by hydrothermal software. C2AH8 (2CaO·Al2O3·8H2O) is generated as a transition phase during the hydration of pure C12A7, while formation of CAH10 (CaO·Al2O3·10H2O) is uncertain. Heat-releasing behavior of Ordinary Portland Cement (OPC) could be noticeably affected by C12A7, especially for the duration of interaction at boundary stage reduces with C12A7 replacement. Correspondingly, all hydration kinetic parameters first increase and then diminish with C12A7 replacement. Simulation results manifest in the main hydration products of OPC being ettringite, C-S-H (Calcium-Silicate-Hydrate) gel, portlandite and brucite. Increasing C12A7 replacement accelerates the consumption rates of gypsum and calcite that are typically included in OPC, and thus the ettringite content is changed and carbonate phases will be produced. Therefore, the microstructure properties of hydrated products of OPC are affected and the compressive strength is influenced. These predications are in good agreement with experimental findings. C12A7 can be used as a functional component to adjust the consumption rate of suphates in OPC, and also components of carbonate phases can be modified in hydrate assemblage.
Polyether Sulfone-Based Epoxy Toughening: From Micro- to Nano-Phase Separation via PES End-Chain Modification and Process Engineering
Authors: Rosetti Yann , Alcouffe Pierre , Pascault Jean-Pierre , Gérard Jean-François , Lortie Frédéric
Published: October 2018

The toughness of a high-performance thermosetting epoxy network can be greatly improved by generating polyether sulfone−based macro- to nano-scale morphologies. Two polyethersulfones (PES) which only differ by their chain-end nature have been successively investigated as potential tougheners of a high-Tg thermoset matrix based on a mixture of trifunctional and difunctional aromatic epoxies and an aromatic diamine. For a given PES content, morphologies and toughness of the resulting matrices have been tuned by changing curing conditions and put into perspective with PES chain-end nature.
Size-Dependent and Property-Independent Passive Microdroplet Sorting by Droplet Transfer on Dot Rails
Authors: Yoon Dong , Tanaka Daiki , Sekiguchi Tetsushi , Shoji Shuichi
Published: October 2018

A fully passive microdroplet sorting method is presented in this paper. On the rails with dot patterns, the droplets were sorted in different ways depending on their size. However, the effect of droplet properties on the threshold size of the sorting was eliminated. The droplet positions on two railways and the Laplace pressure of the droplets on the dot patterns allowed selective droplet transfer according to size. Different gaps between the rails altered the threshold size of the transfer. However, the threshold size was independent of the droplet’s surface tension and viscosity because the droplet transfer utilized only the droplet position and Laplace pressure without lateral flow to sort targets. This feature has a high potential for bio/chemical applications requiring categorization of droplet targets consisting of various mixtures as pre- or post-elements.
Ultrahigh Frequency Ultrasonic Transducers Design with Low Noise Amplifier Integrated Circuit
Authors: Li Di , Fei Chunlong , Zhang Qidong , Li Yani , Yang Yintang , Zhou Qifa
Published: October 2018

This paper describes the design of an ultrahigh frequency ultrasound system combined with tightly focused 500 MHz ultrasonic transducers and high frequency wideband low noise amplifier (LNA) integrated circuit (IC) model design. The ultrasonic transducers are designed using Aluminum nitride (AlN) piezoelectric thin film as the piezoelectric element and using silicon lens for focusing. The fabrication and characterization of silicon lens was presented in detail. Finite element simulation was used for transducer design and evaluation. A custom designed LNA circuit is presented for amplifying the ultrasound echo signal with low noise. A Common-source and Common-gate (CS-CG) combination structure with active feedback is adopted for the LNA design so that high gain and wideband performances can be achieved simultaneously. Noise and distortion cancelation mechanisms are also employed in this work to improve the noise figure (NF) and linearity. Designed by using a 0.35 μm complementary metal oxide semiconductor (CMOS) technology, the simulated power gain of the echo signal wideband amplifier is 22.5 dB at 500 MHz with a capacitance load of 1.0 pF. The simulated NF at 500 MHz is 3.62 dB.
Elemental Concentration in Serpentinitic Soils over Ultramafic Bedrock in Sierra Bermeja (Southern Spain)
Authors: Romero-Freire Ana , Olmedo-Cobo José Antonio , Gómez-Zotano José
Published: October 2018

Although the presence of potentially toxic metals in soils is normally associated with human soil pollution, these elements also appear naturally in environments in which the lithological base contains ultramafic rocks such as peridotites. Serpentinitic soils tend to develop on substrates of this kind, often containing metals with few or no known biological functions, which in some cases are toxic for most plants. This study assessed the level of potentially toxic metals and other elements in an endorheic basin discovered in Sierra Bermeja (Southern Spain), one of the largest peridotite outcrops on Earth. In this location—of particular interest given that basins of this kind are very rare on peridotites—six geomorphoedaphic sub-units on three different substrates were identified. The distribution of microelements in these sub-units was analyzed, and stratified random sampling was performed to identify the major ions with essential functions for living organisms and the potentially toxic metals. The lowest values for macronutrients appeared in the soils formed on ultramafic materials. When analyzing the load of potentially toxic metals, no significant differences were detected between the soils formed on serpentinite and peridotite substrates, although different values were obtained in the soils formed over acidic rocks.
Preparation and Characterization of Electrospun PAN/PSA Carbonized Nanofibers: Experiment and Simulation Study
Authors: Jin Shixin , Yu Jiali , Zheng Yuansheng , Wang Wen-Yi , Xin Binjie , Kan Chi-Wai
Published: October 2018

In this study, we simulated the electric field distribution of side-by-side electrospinning by using the finite element method (FEM), and studied the effects of spinneret wall thickness, spinning voltage and receiving distance on the distribution of the electrostatic field. The receiving distance was selected as a variable in the experimental, a series of PAN/PSA composite nanofiber membranes were prepared by using a self-made side by side electrospinning device. The membranes were tested by Fourier-transform infrared (FTIR), thermogravimetric analysis (TG), and scanning electron microscope (SEM). The prepared membranes were also treated by high-temperature treatment, and the change of fiber diameter and conductivity of the membrane before and after high-temperature treatment were studied. It was found that the PAN/PSA carbonized nanofibers could achieve a better performance in heat resistance and conductivity at 200 mm receiving distance.
Microbiota and Derived Parameters in Fecal Samples of Infants with Non-IgE Cow’s Milk Protein Allergy under a Restricted Diet
Authors: Díaz María , Guadamuro Lucía , Espinosa-Martos Irene , Mancabelli Leonardo , Jiménez Santiago , Molinos-Norniella Cristina , Pérez-Solis David , Milani Christian , Rodríguez Juan Miguel , Ventura Marco , Bousoño Carlos , Gueimonde Miguel , Margolles Abelardo , Díaz Juan José , Delgado Susana
Published: October 2018

Cow’s milk protein allergy (CMPA) is the most common food allergy in infancy. Non-IgE mediated (NIM) forms are little studied and the responsible mechanisms of tolerance acquisition remain obscure. Our aim was to study the intestinal microbiota and related parameters in the fecal samples of infants with NIM-CMPA, to establish potential links between type of formula substitutes, microbiota, and desensitization. Seventeen infants between one and two years old, diagnosed with NIM-CMPA, were recruited. They were all on an exclusion diet for six months, consuming different therapeutic protein hydrolysates. After this period, stool samples were obtained and tolerance development was evaluated by oral challenges. A control group of 10 age-matched healthy infants on an unrestricted diet were included in the study. Microbiota composition, short-chain fatty acids, calprotectin, and transforming growth factor (TGF)-β1 levels were determined in fecal samples from both groups. Infants with NIM-CMPA that consumed vegetable protein-based formulas presented microbiota colonization patterns different from those fed with an extensively hydrolyzed formula. Differences in microbiota composition and fecal parameters between NIM-CMPA and healthy infants were observed. Non-allergic infants showed a significantly higher proportion of Bacteroides compared to infants with NIM-CMPA. The type of protein hydrolysate was found to determine gut microbiota colonization and influence food allergy resolution in NIM-CMPA cases.
Technology-Based Dietary Assessment in Youth with and Without Developmental Disabilities
Authors: Polfuss Michele , Moosreiner Andrea , Boushey Carol J. , Delp Edward J. , Zhu Fengqing
Published: October 2018

Obesity prevalence is higher in children with developmental disabilities as compared to their typically developing peers. Research on dietary intake assessment methods in this vulnerable population is lacking. The objectives of this study were to assess the feasibility, acceptability, and compare the nutrient intakes of two technology-based dietary assessment methods in children with-and-without developmental disabilities. This cross-sectional feasibility study was an added aim to a larger pilot study. Children (n = 12; 8–18 years) diagnosed with spina bifida, Down syndrome, or without disability were recruited from the larger study sample, stratified by diagnosis. Participants were asked to complete six days of a mobile food record (mFR™), a 24-h dietary recall via FaceTime® (24 HR-FT), and a post-study survey. Analysis included descriptive statistics for survey results and a paired samples t-test for nutrient intakes. All participants successfully completed six days of dietary assessment using both methods and acceptability was high. Energy (kcal) and protein (g) intake was significantly higher for the mFR™ as compared to the 24 HR-FT (p = 0.041; p = 0.014, respectively). Each method had strengths and weaknesses. The two technology-based dietary assessment tools were well accepted and when combined could increase accuracy of self-reported dietary assessment in children with-and-without disability.
Reliability of Compartmental Body Composition Measures in Weight-Stable Adults Using GE iDXA: Implications for Research and Practice
Authors: Dordevic Aimee L. , Bonham Maxine , Ghasem-Zadeh Ali , Evans Alison , Barber Elizabeth , Day Kaitlin , Kwok Alastair , Truby Helen
Published: October 2018

The aim of this study was to explore the reliability and precision of body compartment measures, in particular visceral adipose tissue, in weight stable adults over a range of BMIs using GE-Lunar iDXA. Weight-stable participants aged 18–65 years had a total body composition scan on GE-Lunar iDXA either on three separate occasions over a three month period (n = 51), or on a single occasion for duplicate scans with repositioning (n = 30). The coefficient of variation (CV%) and least significant change (LSC) of body compartments were calculated. The CV was higher for all measures over three months (range 0.8–5.9%) compared with same-day precision-scans (all < 2%). The CV for visceral adipose tissue (VAT) was considerably higher than all other body compartments (42.2% three months, 16.2% same day scanning). To accurately measure VAT mass using the GE iDXA it is recommended that participants have a BMI ≥ 25 kg/m2, or VAT mass > 500 g. Changes observed in VAT mass levels below 500 g should be interpreted with caution due to lack of precision and reliability. All other compartmental measures demonstrated good reliability, with less than 6% variation over three months.
Substantial Increase in Compliance with Saturated Fatty Acid Intake Recommendations after One Year Following the American Heart Association Diet
Authors: Zhao Miaomiao , Chiriboga David , Olendzki Barbara , Xie Bin , Li Yawen , McGonigal Lisa Jo , Maldonado-Contreras Ana , Ma Yunsheng
Published: October 2018

The American Heart Association (AHA) dietary guidelines recommend 30–35% of energy intake (%E) be from total fat, <7%E from saturated fatty acids (SFA), and <1%E from trans fatty acid (TFA). This study evaluates the effect of AHA dietary counselling on fat intake. Between 2009 and 2014, 119 obese adults with metabolic syndrome (MetS), (71% women, average 52.5 years of age, and 34.9 kg/m2 of body mass index), received individual and group counselling on the AHA diet, over a one-year study period. Each participant attended 2 individual sessions (months 1 and 12) and 12 group sessions, at one-month intervals. At baseline and one-year, we collected three random 24-h diet recalls (two weekdays and one weekend day). Fat intake patterns over time were analyzed using paired-t test and linear mixed-effect models. There was significant variation on SFA and TFA intake per meal, being highest at dinner, in restaurants, and on weekends. Over the one-year study period, daily intake of total fat, SFA, and TFA decreased by 27%, 37% and 41%, respectively (p-value < 0.01, each). Correspondingly, the percentage of participants complying with AHA’s recommendations, increased from 25.2% to 40.2% for total fat (p-value = 0.02); from 2.5% to 20.7% for SFA (p-value < 0.01); and from 45.4% to 62% for TFA (p-value = 0.02). Additionally, SFA intake for all meal types at home decreased significantly (p-value < 0.05, each). AHA dietary counselling significantly increased the compliance with AHA dietary guidelines, with an eightfold increase in compliance in SFA intake. Nonetheless, ~80% of our participants still exceeded the recommended SFA intake. Substantial efforts are needed to encourage low-SFA and low-TFA food preparation at home, with strong public health policies to decrease SFA and TFA in restaurants and prepared foods.
Design, Synthesis, and Characterization of Schiff Base Bond-Linked pH-Responsive Doxorubicin Prodrug Based on Functionalized mPEG-PCL for Targeted Cancer Therapy
Authors: Zhai Yinglei , Zhou Xing , Zhang Zhiqiang , Zhang Lei , Wang Dianyu , Wang Xinhui , Sun Wei
Published: October 2018

The side effects of doxorubicin (DOX) extremely limit its application in the treatment of malignant tumors. Nano-sized polymeric drugs based on the acidic microenvironment of tissular- or intra- tumor have attracted ample attention because of their potential in reducing side effects. In this research, an amphiphilic diblock copolymer based on poly (ethylene glycol) (PEG) and functionalized polycaprolactone (PCL) was synthesized and utilized as the drug carrier. DOX was chemically conjugated with the polymer via acid-cleavable imine bonds to obtain a novel pH-sensitive DOX prodrug (mPEG-PCL-Imi-DOX). mPEG-PCL-Imi-DOX (24.2 wt % DOX content) formed micelles with an average diameter of 125 nm through a simple solvent evaporation method. The in vitro release profile demonstrated that DOX release of the prodrug micelles was pH-responsive and able to be accelerated with the decrease of pH. In vitro cytotoxicity assay tests revealed that the pH-sensitive DOX prodrug micelles exhibited relatively lower toxicity and similar antitumor efficacy towards MCF-7 cells compared with free DOX. Hence, the DOX prodrug micelles with imine bonds can offer a carrier with great potential for chemo-therapeutics.
Functionalization of Molecularly Imprinted Polymer Microspheres for the Highly Selective Removal of Contaminants from Aqueous Solutions and the Analysis of Food-Grade Fish Samples
Authors: Liang Weixin , Hu Huawen , Zhong Wanting , Zhang Min , Ma Yanfang , Guo Pengran , Xin Meiguo , Yu Mingguang , Lin Haisheng
Published: October 2018

The proliferation of pollution in aquatic environments has become a growing concernand calls for the development of novel adsorbents capable of selectively removing notorious andrecalcitrant pollutants from these ecosystems. Herein, a general strategy was developed for thesynthesis and functionalization of molecularly imprinted polymer microspheres (MIPs) that couldbe optimized to possess a significant adsorption selectivity to an organic pollutant in aqueousmedia, in addition to a high adsorption capacity. Considering that the molecular imprinting alonewas far from satisfactory to produce a high-performance MIPs-based adsorbent, further structuralengineering and surface functionalization were performed in this study. Although the more carboxylgroups on the surfaces of the MIPs enhanced the adsorption rate and capacity toward an organicpollutant through electrostatic interactions, they did not strengthen the adsorption selectivity in aproportional manner. Through a systematic study, the optimized sample exhibiting both impressiveselectivity and capacity for the adsorption of the organic pollutant was found to possess a smallparticle size, a high specific surface area, a large total pore volume, and an appropriate amount ofsurface carboxyl groups. While the pseudo-second-order kinetic model was found to better describethe process of the adsorption onto the surface of MIPs as compared to the pseudo-first-order kineticmodel, neither Langmuir nor Freundlich isothermal model could be used to well fit the isothermaladsorption data. Increased temperature facilitated the adsorption of the organic pollutant onto theMIPs, as an endothermic process. Furthermore, the optimized MIPs were also successfully employedas a stationary phase for the fabrication of a molecularly imprinted solid phase extraction column,with which purchased food-grade fish samples were effectively examined.
Evaluation of Residual Stress Relaxation in a Rolled Joint by Neutron Diffraction
Authors: Hayashi Makoto , Root John H. , Rogge Ronald B. , Xu Pingguang
Published: October 2018

The rolled joint of a pressure tube, consisting of three axial symmetric parts, modified SUS403 stainless steel as an inner extension, Zr–2.5Nb as the pressure tube and an Inconel-718 outer sleeve has been examined by neutron diffraction for residual stresses. It was heat treated to 350 °C for 30, 130 and 635 h to simulate thermal aging over the lifetime of an advanced thermal reactor respectively for 1, 5 and 30 years at an operating temperature of 288 °C. The crystallographic texture has been investigated from cylindric disks cut from the heat treated Zr–2.5Nb pressure tube to determine the proper sample-orientation-dependent hkl reflections for reliable residual strain measurements. Corresponding in situ tensile deformation was carried out to obtain the necessary diffraction elastic constants for the residual stress evaluation. Three-dimensional crystal lattice strains at various locations in the rolled joint before and after the aging treatments for various times were non-destructively measured by neutron diffraction and the residual stress distribution in the rolled joint was evaluated by using the Kröner elastic model and the generalized Hooke’s law. In the crimp region of the rolled joint, it was found that the aging treatment had a much weaker effect on the residual stresses in the Inconel outer sleeve and the modified SUS403 stainless steel extension. In the non-aged Zr–2.5Nb pressure tube, the highest residual stresses were found near its interface with the modified SUS430 stainless steel extension. In the crimp region of the Zr–2.5Nb pressure tube near its interface with the modified SUS430 stainless steel, the average compressive axial stress was −440 MPa, having no evident change during the long-time aging. In the Zr–2.5Nb pressure tube outside closest to the crimp region, the tensile axial and hoop stresses were relieved during the 30 h of aging. The hoop stresses in the crimp region evolved from an average tensile stress of 80 MPa to an average compressive stress of 230 MPa after the 635 h of aging, suggesting that the rolled joint had a good long-term sealing ability against leakage of high temperature water. In the Zr–2.5Nb pressure tube close to the reactor core and far away from the modified SUS403 stainless steel extension, the residual stresses near the inside surface of the pressure tube were almost zero, helping to keep a good neutron irradiation resistance.
Imaging Spectroscopic Analysis of Biochemical Traits for Shrub Species in Great Basin, USA
Authors: Qi Yi , Ustin Susan L. , Glenn Nancy F.
Published: October 2018

The biochemical traits of plant canopies are important predictors of photosynthetic capacity and nutrient cycling. However, remote sensing of biochemical traits in shrub species in dryland ecosystems has been limited mainly due to the sparse vegetation cover, manifold shrub structures, and complex light interaction between the land surface and canopy. In order to examine the performance of airborne imaging spectroscopy for retrieving biochemical traits in shrub species, we collected Airborne Visible Infrared Imaging Spectrometer—Next Generation (AVIRIS-NG) images and surveyed four foliar biochemical traits (leaf mass per area, water content, nitrogen content and carbon) of sagebrush (Artemesia tridentata) and bitterbrush (Purshia tridentata) in the Great Basin semi-desert ecoregion, USA, in October 2014 and May 2015. We examined the correlations between biochemical traits and developed partial least square regression (PLSR) models to compare spectral correlations with biochemical traits at canopy and plot levels. PLSR models for sagebrush showed comparable performance between calibration (R2: LMA = 0.66, water = 0.7, nitrogen = 0.42, carbon = 0.6) and validation (R2: LMA = 0.52, water = 0.41, nitrogen = 0.23, carbon = 0.57), while prediction for bitterbrush remained a challenge. Our results demonstrate the potential for airborne imaging spectroscopy to measure shrub biochemical traits over large shrubland regions. We also highlight challenges when estimating biochemical traits with airborne imaging spectroscopy data.
A Complete Feasible and Nodes-Grouped Scheduling Algorithm for Wireless Rechargeable Sensor Networks in Tunnels
Authors: Liu Xiaoming , Guo Yu , Li Wen , Hua Min , Ding Enjie
Published: October 2018

Limited energy in each node is the major design constraint in wireless sensor networks (WSNs), especially in mine tunnel scenario where the WSNs are required to work perpetually. To overcome this limit, wireless rechargeable sensor networks (WRSNs) have been proposed and studied extensively over the last few years. To keep the sensor nodes working perpetually, one fundamental question is how to design the charging scheme. Considering the special tunnel scenario, this paper proposes a Complete Feasible Charging Strategy (CFCS) to ensure the whole WRSNs is working perpetually. We divide the whole WRSN into several subnetworks and use several mobile chargers (MCs) to charge every subnetwork periodically and orderly. For a subnetwork, we formulate the main problem as a charging time distribution problem. A series of theorems are deduced to restrict the charging configurations, and a group nodes mechanism is proposed to expand the scale of the WRSNs. Finally, we conduct extensive simulations to evaluate the performance of the proposed algorithms. The results demonstrate which of the CFCS boundary theorems is correct and that our proposed CFCS can keep the WRSNs working perpetually. Furthermore, our Nodes-Grouped mechanism can support more nodes in WRSN compared to the state-of-the-art baseline methods.
Optical Acceleration Measurement Method with Large Non-ambiguity Range and High Resolution via Synthetic Wavelength and Single Wavelength Superheterodyne Interferometry
Authors: Lu Qianbo , Pan Dexin , Bai Jian , Wang Kaiwei
Published: October 2018

Interferometric optomechanical accelerometers provide superior resolution, but the application is limited due to the non-ambiguity range that is always less than half of the wavelength, which corresponds to the order of mg. This paper proposes a novel acceleration measurement method based on synthetic wavelength and single wavelength superheterodyne interferometry to address this issue. Two acousto-optical modulators and several polarizers are introduced to the two-wavelength interferometry to create four beams with different frequencies and polarization states, and two ultra-narrow bandwidth filters are used to realize the single wavelength measurement simultaneously. This technique offers the possibility to expand the non-ambiguity range without compromising the high resolution. Also, the superheterodyne phase measurement and the corresponding processing algorithm are given to enable real-time measurement. A prototype is built and the preliminary experimental results are compared with the simulation results, showing good agreement. The results prove an estimated acceleration measurement resolution of around 10 μg and a non-ambiguity range of larger than 200 mg, which is more than 100 times that of the single wavelength-based optical accelerometer.
Design and Verification of Heading and Velocity Coupled Nonlinear Controller for Unmanned Surface Vehicle
Authors: Jin Jiucai , Zhang Jie , Liu Deqing
Published: October 2018

Unmanned Surface Vehicle (USV) is a novel multifunctional platform for ocean observation, and its heading and velocity control are essential and important for autonomous operation. A coupled heading and velocity controller is designed using backstepping technology for an USV called ‘USBV’ (Unmanned Surface Bathymetry Vehicle). The USBV is an underactuated catamaran, where the heading and velocity are controlled together by two thrusters at the stern. The three degrees-of-freedom equations are used for USBV’s modeling, which is identified using experiment data. The identified model, with two inputs, induces heading and velocity tracking, which are coupled. Based on the model, a nonlinear controller for heading and velocity are acquired using backstepping technology. The stability of the controller is proved by Lyapunov theory under some assumptions. The verification is presented by lake and sea experiments.
Proton Triggered Colorimetric and Fluorescence Response of a Novel Quinoxaline Compromising a Donor-Acceptor System
Authors: More Yogesh W. , Padghan Sachin D. , Bhosale Rajesh S. , Pawar Rajendra P. , Puyad Avinash L. , Bhosale Sidhanath V. , Bhosale Sheshanath V.
Published: October 2018

Quinoxaline-based novel acid-responsive probe Q1 was designed on the basis of a conjugated donor-acceptor (D-A) subunit. Q1 shows colorimetric and fluorometric changes through protonation and deprotonation in dichloromethane. With the addition of the trifluoroacetic acid (TFA), UV-vis absorption spectral changes in peak intensity of Q1 was observed. Moreover, the appearance of a new peaks at 284 nm 434 nm in absorption spectra with the addition of TFA indicating protonation of quinoxaline nitrogen and form Q1.H+ and Q1.2H+. The emission spectra display appearance of new emission peak at 515 nm. The optical property variations were supported by time resolved fluorescence studies. The energy band gap was calculated by employing cyclic voltammetry and density functional calculations. Upon addition of triethylamine (TEA) the fluorescence emission spectral changes of Q1 are found to be reversible. Q1 shows color changes from blue to green in basic and acidic medium, respectively. The paper strip test was developed for making Q1 a colorimetric and fluorometric indicator.
Sustainable Freight Transport
Authors: Tavasszy Lóránt , Piecyk Maja
Published: October 2018

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5G Mobile Services and Scenarios: Challenges and Solutions
Authors: Zikria Yousaf Bin , Kim Sung Won , Afzal Muhammad Khalil , Wang Haoxiang , Rehmani Mubashir Husain
Published: October 2018

The Fifth generation (5G) network is projected to support large amount of data traffic and massive number of wireless connections. Different data traffic has different Quality of Service (QoS) requirements. 5G mobile network aims to address the limitations of previous cellular standards (i.e., 2G/3G/4G) and be a prospective key enabler for future Internet of Things (IoT). 5G networks support a wide range of applications such as smart home, autonomous driving, drone operations, health and mission critical applications, Industrial IoT (IIoT), and entertainment and multimedia. Based on end users’ experience, several 5G services are categorized into immersive 5G services, intelligent 5G services, omnipresent 5G services, autonomous 5G services, and public 5G services. In this paper, we present a brief overview of 5G technical scenarios. We then provide a brief overview of accepted papers in our Special Issue on 5G mobile services and scenarios. Finally, we conclude this paper.
An Empirical Study on Green Innovation Strategy and Sustainable Competitive Advantages: Path and Boundary
Authors: Ge Baoshan , Yang Yibing , Jiang Dake , Gao Yang , Du Xiaomin , Zhou Tingting
Published: October 2018

Although green innovation strategy (GIS) is the driving force for the sustainable development of enterprises, while the strategy is implemented, an increased cost and a change in organizational routines will cause an organization to become fragile, and even affect the sustainable competitive advantages. So, the purpose of this paper is to explore the impact path of GIS on sustainable competitive advantages and the implementation boundary of GIS. To explain the impact path, we consider the concept of dynamic capabilities to be the mediator variable. To explain the implementation boundary of GIS, we systematically explore the relationships among GIS, dynamic capabilities and sustainable competitive advantages under different levels of environmental uncertainty. Based on 241 new Chinese green firms, the empirical results find that GIS helps enterprises to gain sustainable competitive advantages. However, in the process of strategy implementation, enterprises should choose appropriate methods according to different degrees of environmental uncertainty. In a low environmental uncertainty, dynamic capabilities play a full intermediary role between GIS and sustainable competitive advantages. However, in a high environmental uncertainty, dynamic capabilities have no mediating effect between GIS and sustainable competitive advantages. This study not only integrates green management theory and strategic management theory but also makes up for the deficiencies in research on these theories and has important reference value for enterprises that seek to carry out green innovation activities.
The Impact of Innovative Technology Exploration on Firm Value Sustainability: The Case of Part Supplier Management
Authors: Son Insung , Kim Jinsu , Park Gwijeong , Kim Sihyun
Published: October 2018

With rapid changes driven by technical advances, innovative technology capacity is a strategic asset unique to a company allocating various tangible and intangible resources, and it promotes technological innovation. This study analyzed the technology applied to iPhone series by Apple from 2007 to 2017 and measured the information effect of innovative technology exploration on the firm value for managing global supply chain (USA, Taiwan, Japan, Korea, and Europe). Adopting the pooled OLS (Ordinary least square) and panel analysis, this study revealed that exploration technology exploring new technologies shows a positive market response in the information effect of sustaining innovation. Results identified that exploitation and exploration can give different results depending on a construct (exploration and exploitation technologies) or congruence (combination and balance). In addition, the results indicate the importance of the balance between exploitation and exploration technologies and rational part supplies management in Apple’s new product development strategy. Analyzing the impact of innovative technology exploration on the firm value for global supply chain management, this study suggests significant implications for strategic decision making for the company to build continuous innovation path through technology search and to secure sustainability of organizations facing rapid changes in technical advances.
Does ESG Performance Enhance Firm Value? Evidence from Korea
Authors: Yoon Bohyun , Lee Jeong Hwan , Byun Ryan
Published: October 2018

We analyze whether a firm’s corporate social responsibility (CSR) plays a significant role in promoting its market value in an emerging market, namely Korea. We employ environmental, social, and corporate governance (ESG) scores to evaluate CSR performances and examine their effect on firm valuation. We find that CSR practices positively and significantly affect a firm’s market, in line with previous studies on developed countries. However, its impact on share prices can differ according to firm characteristics. For firms in environmentally sensitive industries, the value-creating effect of CSR is lesser than for firms that do not belong to sensitive industries. Specifically, corporate governance practice negatively influences the firm value of environmentally sensitive firms. Further, governance practice significantly promotes market value only for chaebols, while investors do not significantly value governance practice carried out by other firms. This finding suggests the value-enhancing effects of governance structure reformation in the former. This work mainly contributes to the literature by verifying a positive CSR-valuation relationship in emerging markets, which provides substantial policy and welfare implications in markets where governments play a major role in promoting CSR. A stronger valuation effect of CSR in chaebols may present economic background for the intervention of the Korean government in the reformation of chaebol.
A Comparative Analysis of Global Datasets and Initiatives for Urban Health and Sustainability
Authors: Taylor Jonathon , Haines Andy , Milner James , Davies Mike , Wilkinson Paul
Published: October 2018

Globally, urban populations are growing rapidly, and in most cases their demands for resources are beyond current limits of sustainability. Cities are therefore critical for achieving national and international sustainability objectives, such as greenhouse gas reduction. Improving sustainability may also provide opportunities for urban population health co-benefits by reducing unhealthy exposures and behaviours. However, there is currently sparse empirical evidence on the degree to which city characteristics are associated with variations in health-related exposures, behaviours and sustainability. This paper examines the feasibility of aggregating empirical data relating to sustainability and health for global cities. An initial scoping review of existing English-language datasets and networks is performed. Resulting datasets are analysed for data types, collection method, and the distribution of contributing cities across climates, population sizes, and wealth. The review indicates datasets are populated using inconsistent methodologies and metrics and have poor overlap of cities between them. Data and organisations tend to be biased towards larger and wealthier cities, and concentrated in Europe and North America. Therefore, despite vast amounts of available data, limitations of reliability, representativeness, and disparate sources mean researchers are faced with significant obstacles when aggregating data to analyse the sustainability and health of globally representative samples of cities.
Valuing Cultural Services of the Kailash Sacred Landscape for Sustainable Management
Authors: Nepal Mani , Rai Rajesh , Das Saudamini , Bhatta Laxmi , Kotru Rajan , Khadayat Madan , Rawal Ranbeer , Negi G.
Published: October 2018

Hindu Kush Himalaya is home to many cultural and religious sites. The literature on the valuation of cultural sites in the mountain terrains is thin. Hence, their development and sustainability are often ignored. Using primary survey data from three different sites in the Kailash Sacred Landscape of India and Nepal, the cultural value of religious sites to the visitors and households living in the surrounding areas was estimated using a modified travel cost method. As visitors travel by foot and offer donations at the religious sites, the estimations account for these aspects in travel cost calculations. For the sample sites, the per year average use value of cultural services was estimated to be USD 2.9 million. Excluding the use value to the outside visitors, the annual estimated use value of cultural services to the approximately 200,000 households of the entire KSL area, which covers 31,252 km2, is over USD 22.6 million, which is over 7% and 15% of the per capita income of Indian and Nepali households, respectively, indicating the importance of the natural-cultural environments in rural livelihoods. The estimated values will help planners manage these cultural sites sustainably for improving the livelihoods of the people living in the area.
Innovation Resilience: A New Approach for Managing Uncertainties Concerned with Sustainable Innovation
Authors: Lv Wen-Dong , Tian Dan , Wei Yuan , Xi Rui-Xue
Published: October 2018

Sustainable innovation is more complex than conventional, market-driven innovation, because companies have to consider a wide range of uncertainties concerned with the environment, society, and economics. This literature review shows that resilience is the prevailing way of thinking in the area of sustainability studies, and the main contribution of resilience to sustainability is how to deal with uncertainties. However, there seems to be a scarcity in the current literature on the conceptualization of resilience in the context of innovation. From the duality view, this paper proposes a new concept of innovation resilience based on two dimensions, stability and adaptability, which contribute to maintaining a high level of innovation efficiency, while at the same time adapting to change. The proposed innovation resilience concept attempts to provide an integration of divergent research streams—innovation management, organizational resilience, and sustainability management theory. We develop a conceptual framework that consists of a set of indicators involving the two dimensions by using multiple case studies, upon which future empirical studies can be based.
Spatial Responses of Net Ecosystem Productivity of the Yellow River Basin under Diurnal Asymmetric Warming
Authors: He Jianjian , Zhang Pengyan , Jing Wenlong , Yan Yuhang
Published: October 2018

The net ecosystem productivity (NEP) of drainage basins plays an important role in maintaining the carbon balance of those ecosystems. In this study, the modified CASA (Carnegie Ames Stanford Approach) model and a soil microbial respiration model were used to estimate net primary productivity (NPP) and NEP of the Yellow River Basin’s (YRB) vegetation in the terrestrial ecosystem (excluding rivers, floodplain lakes and other freshwater ecosystems) from 1982 to 2015. After analyzing the spatiotemporal variations in the NEP using slope analysis, the coefficient of variation, and the Hurst exponent, precipitation was identified as the main factor limiting vegetation growth in the YRB. Hence, precipitation was treated as the control variable and a second-order partial correlation method was used to determine the correlation between diurnal asymmetric warming and the YRB’s NEP. The results indicate that: (i) diurnal asymmetric warming occurred in the YRB from 1982 to 2015, with nighttime warming (Tmin) being 1.50 times that of daytime warming (Tmax). There is a significant correlation between variations in NPP and diurnal warming; (ii) the YRB’s NEP are characterized by upward fluctuations in terms of temporal variations, large differences between the various vegetation types, high values in the western and southeastern regions but low values in the northern region in terms of spatial distribution, overall relative stability in the YRB’s vegetation cover, and changes in the same direction being more dominant than those in the opposite direction (although the former is not sustained); and (iii) positive correlations between the NEP and nighttime and daytime warming are approximately 48.37% and 67.51% for the YRB, respectively, with variations in nighttime temperatures having more extensive impacts on vegetation cover.