bluuebunny/crossref_metadata_2025_split huggingface dataset:
Complexity of temperature‐dependent Raman spectra and phonons properties on the example of carbon nanotubes thin films
Authors: Gertych A.P. , Czerniak‐Łosiewicz K. , Żerańska‐Chudek K. , Dużyńska A. , Zdrojek M. , Judek J. 
Published: June 2020

AbstractWe examine the interplay between intrinsic phonon properties, the variability of material properties, and instrumental uncertainty reflected in temperature‐dependent Raman spectra of inhomogeneous thin films made of two types of carbon nanotubes (metallic and semiconducting), employing statistical Raman mapping. First, we show that the contribution of temperature to Raman peaks properties representing given phonons depends on how the heat is delivered to the sample—global versus local laser heating. We also show that the variability of Raman peaks positions and widths is not negligible and can be separated into instrumental uncertainty and intrinsic material contribution. Finally, we discuss how temperature can affect different correlations and trends in Raman experiments (e.g., the influence of incident laser power on Raman temperature coefficient). Our findings can be useful for improving the reliability of Raman study for various classes of materials, including exfoliated 2D materials, free‐standing thin films made of 2D flakes, or even bulk materials—not only carbon‐based.
Green ultrasound‐assisted processing for extending the shelf‐life of prebiotic‐rich strawberry juices
Authors: Cassani Lucía , Tomadoni Bárbara , del Rosario Moreira María 
Published: June 2020

AbstractBACKGROUNDAdding value to conventional fruit juices by including prebiotic compounds into their formulation and preserving them using non‐thermal, eco‐friendly and safe technologies represent interesting and strategic approaches to diversify healthy and innovative food products. In this context, the effect of ultrasound‐assisted processing (for 15 and 30 min, 40 kHz, 180 W) on microbiological, physicochemical, nutritional and sensory quality of prebiotic‐rich strawberry juices was investigated during storage (14 days, 5 °C).RESULTSCompared to untreated samples, the applied preservation treatments enhanced the microbiological and nutritional quality of samples by significantly reducing native microflora counts (reductions up to 1 log CFU mL−1 at day 14) and increasing the total phenolic content (by more than 25% in comparison to controls at day 14) leading to higher antioxidant capacity of prebiotic‐rich strawberry juices. Ultrasound processing and prebiotic enrichment had no negative effect on sensory attributes of enriched samples, suggesting that this non‐thermal technique successfully retained the fresh‐like attributes of strawberry juices during their shelf‐life, contributing to the good sensory stability of juices. In addition, ultrasound treatments had no detrimental impact on physicochemical quality and ascorbic acid content of enriched samples, showing similar stability to control samples during storage.CONCLUSIONSBased on our results, ultrasound processing appears to be a promising non‐thermal technique for ensuring a stable product from both microbiological and sensory points of view with improved antioxidant capacity and unaltered physicochemical quality while offering a healthier, nutritive and valuable food alternative. © 2020 Society of Chemical Industry
Preparation, characterization and antibacterial mechanism of the chitosan coatings modified by Ag/ZnO microspheres
Authors: Wei Xuqing , Li Qiuying , Wu Chaoling , Sun Tong , Li Xuepeng 
Published: June 2020

AbstractBACKGROUNDTo improve the physicochemical and antibacterial properties of coatings, the chitosan (CS) coatings were respectively prepared by a casting method with zinc oxide (ZnO) and silver (Ag)/ZnO microspheres as modifiers. The chemical structures and micromorphology of ZnO, Ag/ZnO microspheres and CS coatings were characterized by X‐ray diffraction, Fourier‐transform infrared spectroscopy, scanning electron microscopy, transmission electron microscopy and energy dispersive X‐ray spectroscopy. Furthermore, using the dominant spoilage bacteria of aquatic products, Shewanella putrefaciens and Pseudomonas aeruginosa, as objects, the antibacterial activities and mechanism of the CS coatings were investigated.RESULTSThe results show that ZnO and Ag/ZnO microspheres are dispersed homogeneously in the CS coatings. After modified by ZnO and Ag/ZnO microspheres, the mechanical properties and antibacterial abilities of the CS coatings are improved, and that of 0.5% Ag/ZnO‐CS coating is the optimal. For pure CS coating, the bacterial cell membrane is damaged slightly because of the electrostatic interaction between NH3+ of CS and the negative charge on bacterial surface. After treated by ZnO–CS composite coating, the bacterial cell membrane is destroyed badly on account of the earlier‐mentioned ion interaction and disturbing the synthesis of high molecular weight total protein.CONCLUSIONWith regard to Ag/ZnO–CS composite coating, the bacterial cell membrane is damaged seriously and cell contents are completely released due to ion interaction, disturbing the synthesis of high molecular weight total protein and low molecular weight membrane protein. Hence, Ag/ZnO–CS composite coatings are antimicrobial materials and food preservative materials with great potential application. © 2020 Society of Chemical Industry
Clinical Manifestations of Trauma Exposure in Fibromyalgia: The Role of Anxiety in the Association Between Posttraumatic Stress Symptoms and Fibromyalgia Status
Authors: Miró Elena , Martínez M. Pilar , Sánchez Ana I. , Cáliz Rafael 
Published: June 2020

AbstractLittle research has investigated how traumatic experiences relate to fibromyalgia (FM). We explored the presence of trauma exposure in a sample of Spanish participants with FM and examined the associations between (a) the number and type of traumatic experiences and posttraumatic stress disorder (PTSD) symptoms and (b) the severity of clinical manifestations in FM, testing for possible mediation models. Participants were 173 FM patients and 53 healthy controls aged 24 to 66 years. Traumatic event type (physical trauma, physical and sexual abuse, psychological trauma), PTSD symptoms, pain intensity, sleep disturbance, anxiety, depression, coping style, and daily functioning were evaluated via self‐report. Fibromyalgia patients reported a higher percentage of trauma exposure than controls, more traumatic experiences (mainly emotional and physical trauma), and more PTSD symptoms, Hedges’ gs/Cohen's ds = 0.42–0.76. Most FM patients reported having experienced their most distressing traumatic experience and PTSD symptoms before FM diagnosis. PTSD symptom severity was associated with more pain, sleep disturbances, anxiety, depression, coping style, and functional impairment, rs = .23–.33, ps = .025–.008. A multiple mediation analysis showed a significant indirect effect of anxiety in the association between PTSD symptoms and daily functioning. In a subset of FM patients, PTSD symptoms were associated with major clinical symptoms. The results suggest future research should explore the effectiveness of trauma‐focused therapy compared to standard cognitive behavioral therapy for these patients.
Does the Expiratory Disproportion Index Remain Predictive of Airway Stenosis in Obese Patients?
Authors: Calamari Kevin , Politano Stephen , Matrka Laura 
Published: June 2020

Objectives/HypothesisThe expiratory disproportion index (EDI) is the ratio of forced expiratory volume in 1 second divided by peak expiratory flow rate multiplied by 100. An elevated EDI (>50) can help differentiate upper airway stenosis from other dyspnea etiologies, but this has not been verified when considering body habitus. We hypothesize that the predictive value of elevated EDI in diagnosing airway stenosis will be lower in obese patients as compared to nonobese patients.Study DesignRetrospective cohort study.MethodsPatients >18 years old with recorded pulmonary function test values, body mass index (BMI), and airway imaging were reviewed retrospectively from January 2011 to October 2018. EDI was recorded for four cohorts: nonobese and nonstenotic, obese and nonstenotic, nonobese and stenotic, and obese and stenotic, to determine the mean EDI and the sensitivity and specificity of an elevated EDI.ResultsMean EDI values were 66.53 ± 17.66 and 49.55 ± 2.04 in the nonobese stenotic and nonstenotic groups, respectively (P < .01). They were 58.00 ± 10.79 and 45.02 ± 1.42 in the obese stenotic and nonstenotic groups, respectively (P < .01). At a threshold of >50, EDI had a sensitivity of 83.3% and specificity of 56.2% in differentiating between stenotic and nonstenotic cases in the nonobese cohort and 50.0% and 71.9% in the obese cohort.ConclusionsAs previously established, mean EDI values were significantly different in stenotic and nonstenotic patients in both BMI cohorts. However, at the established threshold of >50, EDI was not as sensitive at identifying stenotic cases in obese patients as in nonobese patients. This suggests that the EDI remains useful in obese patients when elevated but should not be relied upon to rule out stenosis.Level of Evidence4 Laryngoscope, 131:606–609, 2021
Evaluation of beneficial and inhibitory effects of nitrate on nodulation and nitrogen fixation in common bean (Phaseolus vulgaris)
Authors: Jiang Yunfei , MacLean Dustin E. , Perry Gregory E. , Marsolais Frédéric , Hill Brett , Pauls K. Peter 
Published: June 2020

AbstractThe effects of applied nitrate on symbiotic nitrogen fixation in legumes are complex. Both inhibition and promotion of nodulation by nitrate have been observed in a dose‐dependent manner. The objectives of this study were to determine the effects of nitrate at different concentrations on root nodulation in different genotypes in common bean (Phaseolus vulgaris). Six genotypes were inoculated with the same rhizobial strain and grown hydroponically in growth pouches in a growth chamber and exposed to six nitrate concentrations, including 0, 2.5, 5, 10, 15, and 20 mM for 4 weeks. The tested genotypes included three recombinant inbred lines (RILs, 25, 46, and 70) that differed in their responses to nitrogen (based on observations of one field growing season), their parents (Mist and Sanilac—registered varieties), which are different in N‐fixing abilities, and one nonnodulating mutant (R99). Our results showed that small amounts of nitrate (2.5 and 5 mM) promoted nodule formation and increased nodule biomass, compared with plants in the 0 nitrate control treatment. In contrast, nitrate concentrations over 10 mM inhibited nodulation, resulting in reductions in nodule number and nodule biomass. Nodulation was completely inhibited by 15‐mM nitrate in all the genotypes. Regression analyses indicated that 5‐mM nitrate is the optimum concentration for promoting nodulation as measured by the total number of nodules formed, the number of effective nodules formed, and the nodule biomass formed. In contrast, nitrogen fixation was inhibited by all levels of nitrate. No genotypic differences were observed in nodulation among the three RILs and their parental cultivars, but all were significantly different than R99, a nonnodulating mutant.
Phospholipid Polymer Hydrogel Matrices with Dually Immobilized Cytokines for Accelerating Secretion of the Extracellular Matrix by Encapsulated Cells
Authors: Zhang Ren , Teramura Yuji , Fukazawa Kyoko , Ishihara Kazuhiko 
Published: June 2020

AbstractConstruction of 3D tissues by various types of cells with specific characteristics is an important and fundamental technology in tissue reconstruction medicine and animal‐free diagnosis system. To do so, an excellent extracellular matrix (ECM) is needed for encapsulation of cells and maintaining cell activity. Spontaneously forming hydrogel matrix is used by complexation between two water‐soluble polymers, 2‐methacryloyloxyethyl phosphorylcholine polymer bearing phenylboronic acid groups and poly(vinyl alcohol). Two cytokines for cell proliferation are immobilized in the hydrogel matrix to control the activities of the encapsulated cells. The cytokine‐immobilized hydrogel matrix can encapsulate both L929 fibroblasts and normal human dermal fibroblasts under mild condition. The physical properties of the hydrogel matrix can follow the proliferation process of the encapsulated cells. The encapsulated cells secrete ECM in the polymer hydrogel networks upon 3D culturing for 7 days. Consequently, the tissue‐mimicking ECM hybrid hydrogels are fabricated successfully.
Construction of Chlorine Labeled ZnO–Chitosan Loaded Cellulose Nanofibrils Film with Quick Antibacterial Performance and Prominent UV Stability
Authors: Ma Wei , Li Lin , Xiao Xintong , Du Haishun , Ren Xuehong , Zhang Xinyu , Huang Tung‐Shi 
Published: June 2020

AbstractIn this study, novel “green” and highly stable biocidal materials composed of cellulose nanofibrils (CNF) and ZnO–chitosan (ZnO–CS) hybrids are constructed by combing vacuum filtration and heat‐press processing without the use of any organic solvent. CNF/ZnO–CS films are soaked in a 10% sodium hypochlorite aqueous solution to endow antibacterial activity. The chlorinated CNF/ZnO–CS samples and chlorinated CNF/ZnO‐CS (CNF/ZnO‐CS‐Cl) possess quick antimicrobial activity against Staphylococcus aureus and Escherichia coli within 30 min of contact compared with CNF and CNF/ZnO–CS controls. The addition of ZnO endows the films with remarkable UV light stability. After exposure to a UV chamber for 24 h, the chlorine loadings on the prepared samples decrease to 0.13%, where 76% of the chlorine loss can be regained after rechlorination. Furthermore, cytotoxicity evaluations reveal the feasibility of the films for in vitro applications. The prepared rechargeable CNF/ZnO–CS–Cl films will have many promising antibacterial applications.
Multifunctional and Efficient Air Filtration: A Natural Nanofilter Prepared with Zein and Polyvinyl Alcohol
Authors: Li Ke , Li Chuanming , Tian Huafeng , Yuan Li , Xiang Aimin , Wang Chaoyang , Li Jinlong , Rajulu A. Varada 
Published: June 2020

AbstractNanofibers prepared by electrospinning technology possess large specific surface area and adjustable fiber diameter. Zein is a hydrophobic plant protein that can interact with pollutants in the air. In this work, using polyvinyl alcohol (PVA) as the auxiliary spinning polymer, zein based nanofiber materials are prepared for air filtration by varying zein/PVA ratio as well as the alcoholysis degree. With the increase of zein content, the diameter of nanofibers decreases gradually, and the nanofibers prepared by PVA with low alcoholysis degree exhibit better micromorphology. The zein based nanofibers prepared after denaturation of zein protein can interact with different types of pollutants. In addition, for the nanofibers prepared by PVA with different alcoholysis degree, the filtration efficiency increases with the increase of zein content when absorbing air pollution particles with different particle sizes and the alcoholysis degree affects the air filtration efficiency. Thus, through controlling zein content and alcoholysis degree, the filtration efficiency of nanofibers is promoted availably. These results indicate that the natural nanofilter prepared with zein and PVA can be used a multifunctional and efficient material for air filtration.
Effect of Hexagonal Boron Nitride Nanoplatelet on Crystal Nucleation, Mechanical Behavior, and Thermal Stability of High‐Density Polyethylene‐Based Nanocomposites
Authors: Chaurasia Ankur , Parashar Avinash , Mulik Rahul S. 
Published: June 2020

AbstractHexagonal boron nitride nanoplatelets (BNNP) significantly enhance the mechanical and thermal properties of high‐density polyethylene. In order to ensure superior dispersibility of BNNP, two different techniques, colloidal solution, and solvent blending, are used for fabricating nanocomposites. Compared to solvent blending, the colloidal solution‐based fabrication technique has superior dispersion capabilities for nanofillers in the PE matrix, which helps in improving the thermal stability and crystallinity in synthesized nanocomposites. A significant increase in the rate of crystallization of polyethylene (PE) is reported at 1% weight fraction of BNNP, which further increases with the increase in weight percentage of BNNP. BNNP acts as a new source of nucleating sites for crystallization in PE that also reduces the size of secondary structures spherulites. Enhanced tensile strength and Young’s modulus of BNNP/PE nanocomposites are reported with the increase in weight contribution of BNNP in the range of 1% to 5%.
Effect of Anchoring Groups on Electron Transfer at Porphyrins‐TiO2 Interfaces in Dye‐Sensitized Solar Cell Application
Authors: Milana Phutri , Nurhayati  , Steky Fry Voni , Ando Yuta , Simanullang Marolop , Sugiyama Mutsumi , Radiman Cynthia Linaya , Suendo Veinardi 
Published: June 2020

AbstractPorphyrin has excellent optical properties as required in solar cell applications, for example, high molar extinction coefficient and high quantum efficiency (≈80%). Excellent optical properties make porphyrin a good candidate as a photosensitizer, that is, in dye‐sensitized solar cells (DSSC). Nevertheless, porphyrins exhibit poor charge transfer resulting in poor cell performance. Poor charge transfer in porphyrins is due to the aggregation, low porphyrin adsorption, and weakly bound porphyrins on the TiO2 surface. Anchoring group attached to the porphyrin ring may play an important role to increase both charge transfer and porphyrin adsorption. This study adopts a strategy to increase the electron transfer from porphyrins to TiO2 by applying different anchoring groups. This strategy aims both to reduce the aggregation and to enhance the binding between porphyrin and TiO2 surface. The presence of methyl and carboxylic acid as the anchoring groups in the porphyrin system can increase the electronic coupling between the porphyrin and the TiO2 surface while also hindering the aggregation. Thus, the presence of anchoring groups improves the electron injection efficiency and cell performance. The type and position of the anchoring groups strongly contribute to the electron injection, thus is discussed in detail.
The Effect of Surface Modification by Sizing Agent on the Water Absorption Capacity of Cassava Starch‐based Biofoam Packaging
Authors: Iriani Evi Savitri , Wahyuningsih Kendri , Oktavia Evi 
Published: June 2020

AbstractBiodegradable foam (biofoam) packaging is made from natural polymers as the main raw material and it is environmentally friendly. However, this packaging is water sensitive, thus it is not suitable for products with high moisture content. The purpose of this study is to determine the effect of surface modification of cassava starch‐based biofoam, using Alkyl Ketene Dimer/AKD as sizing agent, on its hydrophobic characteristics. A completely randomized factorial design is carried out using two factors and two replications. Factor A is a type of pulp of oil palm empty fruit bunches (OPEFB) with different treatment modifications (pulp A; pulp B; pulp C) and factor B is the concentration of AKD (0%; 2.5%; 3.3%; 5.0%). Biofoam is made by thermopressing. Its characterization observed includes physical properties, mechanical properties, and morphological structure. The results show that surface modification of biofoam with AKD significantly effected its moisture content, density, water absorption capacity, and compressive strength. The addition of AKD externally as a sizing agent is able to reduce water absorption capacity by an average of 83.26% compared to biofoam without coating with AKD.
Effect of Solvent Combination on Electrospun Stereocomplex Polylactic Acid Nanofiber Properties
Authors: Septiyanti Melati , Septevani Athanasia Amanda , Ghozali Muhammad , Fahmiati Sri , Triwulandari Evi , Restu Witta Kartika , Meliana Yenny , Matsumoto Takuya , Nishino Takashi 
Published: June 2020

AbstractPolylactic acid (PLA) has been known as bio‐based polymer for the development of bioplastic with promising properties such as biodegradable, biocompatible, non‐toxic, and renewable. However, its low thermal properties have limited its applications. Thus, in this study stereocomplex PLA (sc‐PLA) is investigated with the aim to improve thermal properties by mixing poly L‐lactic acid (PLLA) and poly D‐lactic acid (PDLA) in solution blend combination via electrospinning. The electrospun sc‐PLA fiber is prepared in combination of chloroform (CHCl3), N,N‐dimethylformamide, and hexafluoroisopropanol (HFIP). The effect of solvents in the properties of sc‐PLA is analyzed using Fourier‐transform infrared spectroscopy and X‐ray diffraction (XRD) to understand chemical interaction between PLLA and PDLA. Differential scanning calorimetry and thermo gravimetric analyzer is used to understand the thermal properties of sc‐PLA. It is found that the optimum solvent combination for sc‐PLA nanofiber is CHCl3/HFIP 9:1 with the smallest nanofiber diameter 39.7 nm and the melting point improved by 47 °C compared with neat PLA due to stereocomplexation between PLLA and PDLA.
Preparation of Zeolite‐g‐Polyacrylamide using Radiation Induced Grafting and Its Adsorption Isotherms Study on Several Heavy Metal Ions
Authors: Nuryanthi Nunung , Syahputra Akhmad Rasyid , Oktaviani  , Puspitasari Tita , Pangerteni Dewi Sekar , Kurniawan Rendi , Astuti Dyah Ayu Tri , Darwis Darmawan 
Published: June 2020

AbstractZeolite‐g‐polyacrylamide is prepared by using the radiation induced grafting technique. Clinoptilotite, a natural zeolite, is used as the base matrix. In order to increase the degree of grating of polyacrylamide into the zeolite, its surface is modified with silane compound before the grafting reaction and applied a poor solvent method in the grafting reaction, i.e., a mixture of toluene and H2O. The irradiation doses are varied from 10 to 50 kGy. The grafting parameters are 40% w/w acrylamide, temperature 60 °C and 3 h grafting time. The highest degree of grafting is 93% at an irradiation dose of 25 kGy. The zeolite‐g‐polyacrylamide is then characterized with FTIR spectroscopy and SEM observation. Batch experiments are also carried out to investigate the adsorption capacity for ion Cr3+, Pb2+, and Zn2+. The maximum adsorption capacities of zeolite‐g‐polyacrylamide are 544, 345, and 1046 mg g−1 for ion Cr3+, Pb2+, and Zn2+, respectively. The equilibrium data are also tested with Langmuir and Freundlich isotherm to find the best suitable adsorption isotherm system.
Properties of Natural Rubber/Chloroprene Rubber Blend for Rubber Fender Application: Effects of Blend Ratio
Authors: Anggaravidya Mahendra , Amry Akhmad , Arti Dewi K. , Kalembang Eryanti , Susanto Herri , Hidayat Ade S. , Limansubroto Caroline D. 
Published: June 2020

AbstractNatural rubber is widely known to possess good mechanical properties. However, due to the existence of numerous reactive double bonds on the molecular backbone, natural rubber is highly susceptible to degradation by thermal aging. To overcome such shortcomings, natural rubber is frequently blended with synthetic rubbers such as chloroprene rubber. Chloroprene rubber is one of the most important specialty rubber for nontire application, for example rubber fender. The present study investigates the effects of two different blend ratios of natural rubber (standard Indonesian rubber or SIR 10) and chloroprene rubber on the cure, tensile properties, and morphology of rubber blends. The blends of SIR 10/chloroprene rubber are prepared by using laboratory kneader and laboratory two‐roll mill. Rubber blending is made from mixture of natural rubber SIR 10 and synthetic rubber chloroprene rubber with variation of SIR 10/chloroprene rubber ratio PF1 100/0; PF2 70/30; PF3 30/70; PF4 0/100 phr. Furthermore, each variable is tested to determine the rheological and mechanical properties including tensile strength, elongation at break, hardness, and compression set. The addition of chloroprene rubber also causes an increment in the tensile strength and elongation at break. However, only PF3 shows satisfied result compared to the requirements standard (ISO 17357‐1:2014 Ship and Marine Technology‐Floating Pneumatic Rubber Fenders).