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Highlights To improve the thermal conductivity and mechanical properties of graphene‐acrylonitrile butadiene‐styrene plastic (ABS) composite, sub‐phosphite‐based ionic liquid (IL) was synthesized, and its structure was characterized by FTIR, NMR, and mass spectrometry. IL was as a modifier, and graphite powder (G powder) was modified by the ball milling method to obtain functional graphene thermal conductive filler (G‐IL). The structure and morphology of G‐IL were characterized by FTIR, X‐ray photoelectron spectroscopy (XPS), XRD, scanning electron microscopy (SEM), and transmission electron microscopy (TEM). The results of the Molau test showed that the presence of IL improved the interfacial interaction of G‐IL and ABS, enhanced the dispersion of G‐IL in the ABS matrix, made G‐IL contact with each other, and it was easier to establish a thermal conduction network and promote phonon transfer. The thermal conductivity of 9 wt% G‐IL/ABS composite was 0.392 W·m−1·k−1, which was 96% and 14% higher than that of pure ABS and G/ABS composite, respectively. The tensile strength and bending modulus of 9 wt% G‐IL/ABS composite were 44.89 and 2124.37 MPa, which were 13% and 11% higher than those of pure ABS, respectively. The impact strength of 9 wt% G‐IL/ABS composite was 34.17 kJ/m2. It was 18% and 7% higher than that of pure ABS and 9 wt% G‐IL/ABS, respectively. Phosphorus imidazole ionic liquids were prepared. Graphene was modified by ionic liquids through non‐covalent. Enhanced mechanical properties and thermal conductivity of G‐IL/ABS composites. [ABSTRACT FROM AUTHOR]

Printability and interlayer adhesion are the most critical issues in 3D printing of immiscible polymer blends. It can affect structural integrity and mechanical performance of the printed parts. In this work, an effective strategy to improve the printability and interlayer adhesion of immiscible acrylonitrile‐butadiene‐styrene/polypropylene (ABS/PP) blends was implemented by introducing styrene–ethylene/butylene–styrene copolymer grafted with maleic anhydride (SEBS‐g‐MA) as a compatibilizer. The printability of the developed blends was investigated using rheological properties such as absolute value of complex viscosity, loss tangent and die‐swell ratio. Interestingly, it was found that the additive manufactured blends with 20 wt% SEBS‐g‐MA loading showed improved interlaminar shear strength, impact strength, Young's modulus and toughness as compared with the pure blend. Fractography analysis revealed that two different possible failure mechanisms, interface and matrix failure were apparent in the 3D printed samples with and without SEBS‐g‐MA content. This work provides a promising pathway to fabricate the complex structures from polymer blends with improved mechanical properties and surface finish. Highlights: This study demonstrated improved interlayer adhesion at the printed interface of immiscible ABS/PP blends in presence of SEBS‐g‐MA.The printability of the developed blends was predicted from rheological properties.Additive manufactured blends with SEBS‐g‐MA loading showed improved mechanical performance. [ABSTRACT FROM AUTHOR]

Biocomposites made from natural fibers have attracted significant attention in recent years owing to the global concern regarding plastic accumulation. In this investigation, ramie fiber was employed as a natural fiber reinforcement in the acrylonitrile butadiene styrene (ABS) matrix to enhance the biodegradability of the polymer composite. ABS/ramie fiber composites were prepared by compression molding with various wt% (5, 10, 15, and 20 wt %) of ramie fibers within the ABS matrix. Subsequently, the biodegradability, water absorption, mechanical properties, viscoelastic behavior, and thermal characteristics of the prepared composites were evaluated. The biodegradation test results demonstrated that there was a positive correlation between the concentrations of fibers in neat ABS. The maximum biodegradation of the composites was 2.56% at 20 wt% ramie fibers in the ABS matrix. Moreover, an increase in the wt% of ramie fiber led to an increase in water absorption. Although the tensile strength and impact strength decreased with increasing fiber content, the tensile modulus of the ABS/ramie fiber composites initially increased up to 5 wt% fiber and then started decreasing, and the natural fibers in ABS reduced the viscoelastic properties. The objective of developing ABS/ramie fiber composites is to utilize them as environmentally sustainable materials in automotive manufacturing industry. [ABSTRACT FROM AUTHOR]

Acrylonitrile‐butadiene‐styrene (ABS) based composites with a high content of tungsten and bismuth oxide were developed using an innovative process to obtain lead‐free x‐ray shielding materials. ABS was chosen for its good mechanical properties and its widespread availability as a recycled material. The composites underwent flexural tests, Shore D hardness tests, thermogravimetric and morphological analysis, and their x‐ray attenuation properties were determined through numerical simulations and experimental measurements. Despite their high filler content (up to 75 wt%), the composites showed good filler dispersion within the polymeric matrix and maintained their mechanical properties. Across the investigated energy range (50–150 kV), the lead equivalence for x‐ray shielding was achieved with composite plates containing 75 wt% of tungsten and bismuth oxide, at thickness values corresponding to a weight increase of only 29% and 36%, respectively, in comparison to lead. These findings pave the way for a new generation of lead‐free x‐ray shielding materials. Moreover, their mechanical properties, including flexibility for potential application in wearable personal protective equipment, can be tailored by adjusting the filler content. Highlights: High filler content lead‐free ABS composites with WO3 and Bi2O3 were developed.They show good polymer/filler interfacial adhesion and flexural properties.Numerical simulations of their x‐ray shielding properties were performed.Experimental tests with polychromatic sources confirmed good x‐ray attenuation.Results pave the way for the development of new lead‐free x‐ray shielding systems. [ABSTRACT FROM AUTHOR]

Multiwall carbon nanotubes (MWCNTs) can be spread out in acrylonitrile butadiene styrene (ABS) using a twin‐screw micro‐compounding extruder. It can significantly improve the mechanical properties of 3D‐printed objects. Dispersed MWCNTs in pure ABS to develop the nanocomposites through a two‐time micro compounding extruding process. 3D printed filaments with a diameter of 1.75 mm have been prepared by processing the acquired composite structure through a filament extruder. The mechanical and other properties of 3D printed pure ABS and 1, 2, and 3 wt.% of the fused deposition modeling (FDM) process were studied for MWCNTs/ABS composites. Compared with pure ABS, the tensile and thermal properties were significant for 1, 2, and 3 wt.% of MWCNTs/ABS composites. Fourier transform infrared spectroscopy (FTIR), X‐ray diffraction (XRD), thermogravimetric analysis (TGA), and scanning electron microscopy (SEM) were also analyzed for 0, 1, 2, and 3 wt.% MWCNTs/ABS composites. Additive manufacturing (AM) processes have recently been emphasized for their applications in electronics, aerospace, biomedical, and automobile engineering. [ABSTRACT FROM AUTHOR]

Waste plastic exposed to the environment creates problems and is of significant concern for all life forms. To reuse the waste plastic in a well‐organized manner and make it more productive, extrusion‐based additive manufacturing, specially fused deposition modeling technique, can be an effective way. Hence, the primary objective of this work is to reuse ABS waste for developing sustainable three‐dimensional printing filaments. A mixed feedstock processing approach is used to develop filaments, in which recycled ABS is blended with virgin ABS in weight ratio of 10%–50%. The rheological and thermo‐mechanical properties of the extruded filaments were examined. Results indicated that increasing extrusion temperature from 190°C to 195°C produced significant physical changes in ABS blends. There is a breakdown of styrene acrylonitrile and butadiene component in ABS which causes strain hardening and material stiffening. The Young's modulus, yield strength and ultimate tensile strength of 80% RABS/20% VABS filament were found to be 2329, 34.814 and 40.82 MPa, respectively, which is close to VABS filament. The novel filament produced from recycled/virgin ABS blends has the capability to replace commercially available ABS filaments for fabricating high‐quality plastic parts through an additive manufacturing routine. [ABSTRACT FROM AUTHOR]

Herein, we prepared toughened and electrical nanocomposites of polyamide 6 (PA6)/acrylonitrile‐butadiene‐styrene (ABS) compatibilized with maleic anhydride‐grafted acrylonitrile‐butadiene‐styrene (ABS‐MA). Functionalized multi‐walled carbon nanotubes (MWCNTf) were used as conductive nanofillers. Nanocomposites were processed in an internal mixer and injection molded. Torque rheometry, impact strength, elastic modulus, heat deflection temperature (HDT), differential exploratory calorimetry (DSC), melting and crystallization kinetic curves, electrical conductivity, scanning electron microscopy (SEM) and transmission electron microscopy (TEM) were evaluated. Torque increased with the MWCNTf content in the PA6/ABS/ABS‐MA/MWCNTf nanocomposites, suggesting an increase in viscosity. The MWCNTf were well dispersed in the nanocomposites, generating an electrical percolation path. The impact strength of the PA6/ABS/ABS‐MA/MWCNTf nanocomposites was superior to that of pure PA6, indicating improved flexibility and toughness. The addition of 1 pcr of MWCNTf in the PA6/ABS/ABS‐MA system was sufficient for antistatic application, with a 221% higher impact strength, compared to pure PA6. The DSC studies showed that the crystallization temperature of the nanocomposites shifted to higher temperatures. This was due to the MWCNTf that accelerated crystallization. Additionally, the nanocomposites HDT increased by 20°C compared to the PA6 matrix, suggesting a superior thermomechanical strength. The developed nanocomposites show improved mechanical, electrical, and thermomechanical properties. Therefore, they exhibit great technological potential for application in antistatic packaging. [ABSTRACT FROM AUTHOR]

Characterizing and understanding composite polymeric systems' rheological behavior is essential to tune their melt flow in polymer processing machinery. Also, rheological tests are suitable tools to evaluate the microstructure and interface adhesion of polymeric composites, which are relevant parameters on the composite performance in their applications. Poly(acrylonitrile‐co‐butadiene‐co‐styrene) (ABS) and its composites are essential materials used to manufacture consumer goods necessary to maintain the quality of life of human beings. In this work, we report on polymer systems based on ABS and poly(styrene‐block‐ethylene‐co‐butylene‐block‐styrene)‐graft‐maleic anhydride (SEBS‐g‐MA) as polymer matrix containing dispersed copper microparticles (ABS:SEBS‐g‐MA:Cu). Polydopamine, a bioinspired polymer, was applied as a filler‐matrix interface compatibilizer of the composites. The linear viscoelastic rheological measurements evidence a shear‐thinning behavior for the composites, and the polydopamine coating affects the polymer phase's relaxation time. The cohesive energy density (Ec) and SEM micrographs indicate good adhesion between copper and ABS:SEBS‐g‐MA due to polydopamine interfacial adherence. [ABSTRACT FROM AUTHOR]

This article examines the effect of the addition of nanosheets of polymeric carbon nitride (NPCN) on the frictional, mechanical, thermal, and morphological properties of acrylonitrile butadiene styrene (ABS) system. A series of ABS/NPCN nanocomposites were prepared by varying NPCN concentration using the solution casting and compression molding methods. NPCN were prepared from melamine by thermal treatment and characterized using UV–Vis diffuse reflectance spectroscopy, photoluminescence spectroscopy, scanning electron microscopy, and transmission electron microscopy. Fourier transform infrared spectroscopy and X‐ray diffraction analysis were utilized to investigate the chemical and crystal structure of NPCN, ABS, and ABS/NPCN composites. The wettability of the composites was analyzed using contact angle studies. The incorporation of NPCN into the ABS matrix improved the thermal stability and tensile strength of the ABS/NPCN composites. The addition of NPCN increased the initial decomposition temperature and char yield of the composites. The frictional analysis results indicated that the presence of NPCN filler significantly influences the friction coefficient (decreased by 35%) and wear loss (reduced by 67%) of the nanocomposites. [ABSTRACT FROM AUTHOR]

Summary: Cone calorimeter and controlled atmosphere cone calorimeter experiments were conducted on various samples. The intent of the tests was to examine the behavior of uniform and composite samples in a range of thicknesses, irradiances, and oxygen concentrations. Single, uniform layers of acrylonitrile butadiene styrene (ABS) were compared to a composite mix, comprising of ABS with a surface layer of cardboard and a secondary layer of polyethylene bubble wrap (intended to represent a potential storage arrangement). The horizontal samples have been tested at irradiances of 25 and 50 kW/m2 and oxygen concentrations of 20.95%, 17%, and 15% to examine a range of significant variables. Results for the uniform arrangement indicated various correlations, previously observed in the works of others, such as the relationships typically described between applied heat flux, ignitability, heat release rate and the effect of the introduction of hypoxic conditions. However, results were shown to change significantly when samples were arranged to feature composite layers. A hypothesized cause of the behavioral change, namely the soot and char residual introduced from the incomplete combustion of the cardboard layer, highlights further important variables that require consideration in material testing under hypoxic conditions. Such variables, namely specific material behaviors and sample orientation, must be sufficiently captured in the design methodologies of systems reliant upon the introduction of hypoxic conditions. It is concluded that sufficiently capturing a wider range of variables in burning materials under hypoxic conditions will introduce further design resilience and help optimize fire protection/prevention methods. [ABSTRACT FROM AUTHOR]

Polypropylene (PP) blends with acrylonitrile‐butadiene‐styrene (ABS) were prepared using the styrene‐ethylene‐butylene‐styrene copolymer (SEBS) as a compatibilizing agent. The blends were prepared in a co‐rotational twin‐screw extruder and injection molded. Torque rheometry, Izod impact strength, tensile strength, heat deflection temperature (HDT), differential scanning calorimetry, thermogravimetry, and scanning electron microscopy properties were investigated. The results showed that there was an increase in the torque of PA6/ABS blends with SEBS addition. The PP/ABS/SEBS (60/25/15%) blend showed significant improvement in impact strength, elongation at break, thermal stability, and HDT compared with neat PP. The elastic modulus and tensile strength have not been significantly reduced. The degree of crystallinity and the crystalline melting temperature increased, indicating a nucleating effect of ABS. The PP/ABS blends compatibilized with 12.5% and 15% SEBS presented morphology with well‐distributed fine ABS particles with good interfacial adhesion. As a result, thermal stability has been improved over pure PP and the mechanical properties have been increased, especially impact strength. In general, the addition of the SEBS copolymer as the PP/ABS blend compatibilizer has the advantage of refining the blend's morphology, increasing its toughness and thermal stability, without jeopardizing other PP properties. [ABSTRACT FROM AUTHOR]

The composition analysis of the acrylonitrile butadiene styrene (ABS) copolymer was performed using a method combining elemental analysis and 1H nuclear magnetic resonance (NMR) spectroscopy. The physicochemical properties of ABS are determined by the relative contents of the constituent monomers. However, because ABS undergoes a complicated microstructural change during the polymerization process, it is difficult to accurately analyze the relative contents using only a typical method. In this study, a combination of nitrogen elemental analysis and 1H NMR spectroscopy was proposed as an analytical method that can consider the effects of changes in the microstructures. This approach confirmed whether the ABS samples were close to meeting the specifications. In addition, the composition analyses of polylactic acid/ABS blends, polycarbonate/ABS blends, and a polyamide 6/ABS mixture sample indicate that the obtained results were consistent with the expected values, thereby demonstrating that this combined analytical approach can be applied to various types of ABS copolymer systems. [ABSTRACT FROM AUTHOR]

This paper proposes an improved active disturbance rejection control (ADRC) method for output tracking of uncertain plants with unknown control direction. A basic design procedure in the ADRC methodology is to assume the exact knowledge of the system control direction, that is, the sign of its input channel coefficient. Recent works have been proposed to relax such a requirement by performing modifications in its control structure. However, despite considering uncertainties in the input coefficient, many variants of the ADRC method still assume the knowledge of the control direction, which means that the control gain is uncertain in norm, but not in sign. For solving the latter case, and also aiming to generalize the earlier ADRC results for a larger class of systems, the present work incorporates the concept of monitoring functions in the controller design. It is a switching‐based strategy whose main function is to determine the correct sign of the control direction, which is directly related to the sign of the plant input channel coefficient. As a consequence of the resulting new control method, exponential stability with respect to a small residual set is guaranteed for the output tracking problem in closed‐loop. Numerical simulations are performed and discussed initially in an academical example, only for comparing the robustness properties concerning the unknown control direction of the proposed strategy with another ADRC methodology. In the sequence, the proposed ADRC strategy based on monitoring function is applied to the automotive plant system of an Anti‐Lock Braking System for illustrating its performance. [ABSTRACT FROM AUTHOR]

The attention to pursuing biodegradable fillers as reinforcement in three‐dimensional (3D) printing filament and enhancing interlayer adhesion has led to the exploitation of agricultural biomass. In this study, organosolv lignin fillers can act as the aforementioned twofold purposes in preparing acrylonitrile butadiene styrene (ABS) filament for fused deposition modeling (FDM). In this study, the lignin polymer composites were homogenized with graphene nanoplatelets (GnPs) as a reinforcer. Essentially, ABS 3D printing at 90o with the reinforcement fillers shows a significant increment in the mechanical properties owing to better interlayer adhesion. The printed product promotes a substantial improvement on the tensile stress up to 29.1% compared with neat polymers. Furthermore, 3D printing using lignin/GnP composite filaments shows the feasibility of biofillers to be used as filaments for FDM 3D printing of complex geometries even though the surface finish has been affected. [ABSTRACT FROM AUTHOR]

Acrylonitrile‐butadiene‐styrene (ABS) functionalization is industrially important since it can wide the ABS application range. However, grafting of functional groups must be effective. This work aimed evaluating the effectiveness of ABS functionalization in an internal mixer, using maleic anhydride (MA) and dicumyl peroxide (DCP) as initiator, at 2.5% and 5.0%; and 0.3% and 0.5% contents respectively. Torque rheometry, melt flow rate (MFR), titration, Fourier transform infrared spectroscopy (FTIR), contact angle, thermogravimetry (TG), differential scanning calorimetry (DSC), and X‐ray diffraction (XRD) were used to collect the main parameters of produced compounds. For ABS with 5% MA and 0.5% DCP, an efficiency of 62% was reached with the degree of grafting 3.1% MA. FTIR spectra confirmed new band in ABS chain in 1780 cm−1 due to the carbonyl group. Reduction in contact angle and thermal stability were verified, whereas MFR and torque rheometry suggested that viscosity decrease is most due to the molecular weight reduction. In general, MA grafted ABS presented proper functionalization with great potential for applications as reactive compatibilizer. [ABSTRACT FROM AUTHOR]

A composite electrode based on acrylonitrile‐butadiene‐styrene and graphite chemically modified with a bismuth film (AGCE‐BiF) was applied for the simultaneous determination of Cd2+ and Pb2+ in gasoline samples. Extraction induced by microemulsion breaking (EIMB) was used for the first time in the preparation of the samples for electroanalysis. AGCE‐BiF was characterized by SEM, AFM, CV, and SWASV. The sensor showed an increase in sensitivity via in situ modification with bismuth film. The LOD was 4 μg L−1 for Cd2+ and 2 μg L−1 for Pb2+. The results showed satisfactory recoveries and precision, being statistically compatible to those obtained with FAAS. [ABSTRACT FROM AUTHOR]

Background: Precise diagnosis and classification of CBWA cases can be challenging. BSA are considered when there is a body wall anomaly, skeletal abnormalities, and the umbilical cord is anomalous, absent or rudimentary, and LBWC when there is a body wall and structural limb anomalies with or without craniofacial abnormalities. Methods: PubMed was searched for body stalk anomalies, limb body wall complex, body stalk anomalies and amniotic band syndrome, and limb body wall complex and amniotic band syndrome. Sixty nine articles were selected and reviewed. This article systematically classifies the variants of CBWA in 218 cases, the study is based on the embryological and anatomical criteria established by Martín‐Alguacil and Avedillo to study BSA in the pig. Results: Eight different BSA presentation were defined. One hundred and eighty nine cases were classified as BSA, from which five were Type I, nine Type II, 20 Type III, 57 Type IV, 11Type V, 24 Type VI, 11 Type VII, and 52 Type VIII. Twenty six cases presented cranial phenotype, 114 abdominal phenotype, 42 cranio/abdominal overlapping phenotype, and five without defined phenotype. In addition, 52 BSA cases presented some kind of spinal dysraphism (SPDYS) and were classified as BSA/SPDYS, most of these cases did not show structural limb anomalies, except for three cases and were classified as LBWC/SPDYS. Conclusion: This morphology‐based classification represents a useful tool for clinical diagnosis, it helps to quantify and to evaluate CBWA in a precise, objective manner. [ABSTRACT FROM AUTHOR]

3D printers are becoming increasingly efficient and economical, and thus more widespread and easily accessible to consumers and businesses. They have been used to print nefarious objects such as guns and suppressors. Previous research has documented the release of dust particles during the printing process; however, little has been written about the morphology and chemical features that define the dust emitted by these printers. This study was undertaken to recover, analyze, and identify the dust produced during the printing process in the context of forensic trace evidence analysis. Samples were collected from a variety of 3D fused deposition modeler printers, representing both consumer and commercial grade models. This work focused on printers that use thermoplastic filaments composed of acrylonitrile butadiene styrene (ABS) or polylactic acid (PLA), two of the most commonly used filament polymers. Swabs were used to collect dust within the printer chamber and then processed to isolate the dust particles. Particles produced from ABS filaments are most easily recognized via light microscopy through a combination of color, morphology, and fluorescence. The composition of these particles can be confirmed through analysis by either FTIR or Raman microspectroscopy. These methods can also be used to identify ABS fillers and pigments within the printer dust particles. In contrast, dust from PLA printers consistently contained finer, submicron‐sized particles that could be observed by field emission scanning electron microscopy. Because the size of the particles precludes their identification using vibrational spectroscopy methods, pyrolysis‐GC‐MS was used to confirm the presence of PLA. [ABSTRACT FROM AUTHOR]

Poly(lactic) acid (PLA) is a biodegradable polymer that has attracted interest as a potential substitute for some thermoplastic polymers. However, its advanced brittleness at room temperature represents one of the major drawbacks for its general use. In this work, PLA was modified by reactive extrusion (PLAREx) to enhance the rheological behaviour and to limit its degradation. The modified material was melt blended with acrylonitrile–butadiene–styrene (ABS), and the resultant morphology, rheological, thermo‐mechanical and fracture behaviour were analysed. Since PLA does not have reasonable compatibility with ABS, maleic‐anhydride‐grafted ABS (ABS‐g‐Ma) was used as compatibilizer. The morphology of the PLAREx/ABS samples resulted in the formation of small ABS rods in the matrix. The presence of maleic anhydride contributed to reducing the interfacial energy of the blends and to obtaining finer micro‐domains of the ABS‐rich phase in the PLAREx matrix. In the compatibilized blends, the presence of elongated ABS‐rich phases opposed free crack propagation and contributed to the increase in fracture energy in comparison to neat PLA. © 2020 Society of Chemical Industry [ABSTRACT FROM AUTHOR]

The current perception regarding the implementation of the Nagoya Protocol is that the national implementations bring complexities for both the provider countries and users of genetic resources (GR) which result in less willingness to access GR. Users frequently face non‐compliance penalties or public notoriety due to the lack of clarity of access and benefit‐sharing (ABS) obligations. Less access would inevitably result in fewer benefits shared and this vicious cycle would jeopardise the success of the entirety of the ABS system. Therefore, there is an apparent need for a methodology in regulating ABS models in a way that is supportive for both the provider countries and users. This article serves as the introductory part of a comprehensive study on creating a methodology for mutually supportive ABS systems for users and providers by introducing international ABS goals and the stakeholders' (both users and providers) perceptions thereof. [ABSTRACT FROM AUTHOR]

The European stability mechanism (ESM) is a permanent crisis resolution mechanism for euro area countries. We analysed the costs of the current ESM refinancing design and evaluated an alternative asset‐backed securities (ABS) structure under different scenarios. Our simulation results indicate that switching to an ABS structure could substantially lower the ESM refinancing rate by up to 3.5 per cent. Moreover, the current structure severely limits the ESM's potential to stabilize financial markets. As an unintended consequence, the ESM is likely to act as a crisis accelerant rather than a stabilizer in the most likely case of requests for medium‐sized financial support from distressed ESM members at a time when other ESM countries might be unwilling or unable to provide new capital. [ABSTRACT FROM AUTHOR]

This work aims to determine the influence of fused deposition modeling (FDM) printing parameters on the mechanical properties of parts fabricated on an Ultimaker2 printer with acrylonitrile butadiene styrene (ABS). The effect of several parameters such as interlayer cooling time (ILCT), nozzle diameter, infill density, raster angle and layer thickness on the ultimate tensile strength, yield strength, and elastic modulus of produced parts was evaluated. Two independent studies were conducted: a first study dedicated to the ILCT and a second study where the influence of other parameters was evaluated through a design of experiments (DoE) approach. Both studies were carried out through the execution of standard tensile tests. The statistical analysis of tensile tests results was processed with the ANOVA methodology. The obtained results indicate that a reduced ILCT improves the tensile strength of parts. It is shown that nozzle diameter and infill density are the parameters that most influence the mechanical properties of ABS, with the upper range selected values improving the studied mechanical properties. The raster angle configuration of (−45o/45o) benefits UTS and yield strength of ABS samples. Interactions of nozzle diameter on layer thickness were detected. It was observed that smaller layer thickness promotes a higher elastic modulus and UTS; however, for thinner layers (0.06‐0.10 mm), no significant differences were found on strength of samples due to potential high distortion levels. [ABSTRACT FROM AUTHOR]

The United Nations' Convention of Biological Diversity (and the Nagoya Protocol on Access to Genetic Resources and the Fair and Equitable Sharing of Benefits Arising from their Utilization), the Food and Agriculture Organisation of the United Nations' International Treaty for Plant Genetic Resources for Food and Agriculture, and the World Health Organisation of the United Nations' (WHO) Pandemic Influenza Preparedness Framework all set out schemes for access and benefit sharing (ABS) some biological materials. This article addresses the apparent conflict between the general obligations in these agreements to disclose and exchange information and dealing with information as a resource derivative within the ABS transaction. This latter dealing is a closed domain for information under the ABS schemes where information is a resource derivative that is a part of the ABS transaction. Treating information as a resource derivative within the ABS transaction is likely to impose unnecessary and inefficient burdens on ABS transactions. After reviewing the recent developments, the article postulates a risk framework for valuing information as a part of the ABS transaction, or alternatively, a charge, tax, or levy to externalize the costs so that information remains available to be disclosed and exchanged promoting more and better science and research. [ABSTRACT FROM AUTHOR]

The KMnO4‐H3PO4‐H2SO4 system was used to roughen and hydrophilically modify on the surface of ABS resin at different etching temperatures, and then, electroless nickel plating process was carried out. The surface of ABS resin after etching was characterized by XPS and SEM. It is found that the surface etching effect of ABS resin is relatively good when the etching temperature is 65°C. The resin surface generates ─OH and ─COOH hydrophilic groups, the roughness of resin surface is increased significantly, and the surface hydrophilic contact angle is 40.51°. After electroless nickel plating on the ABS etching surface, the bonding force of the coating can reach 2.73 MPa. Electrochemical polarization curves and electrochemical impedance spectra also show that the corrosion resistance of coating after 65°C etching postprocessing is improved. [ABSTRACT FROM AUTHOR]

In this study, the effect of acid-treated wood fiber modifications on the mechanical behaviors of HDPE/ABS blend is investigated. Wood fiber/HDPE/ABS composites were fabricated by incorporating acid-treated wood fiber into HDPE/ABS blends. The results showed that both the tensile strength and flexural strength of wood fiber/HDPE/ABS composites were greater than those of HDPE/ABS blend, regardless of wood fiber modification. The results also showed that the impact strength of HDPE/ABS composites is improved by the addition of wood fiber. Scanning electron microscopic (SEM) examination of fractured surfaces showed that the improvement in the mechanical properties of the wood fiber/HDPE/ABS composites was attributed to the improved dispersion of wood fiber in the HDPE/ABS and the better interfacial characteristics caused by the acid treatment of the wood fiber. [ABSTRACT FROM AUTHOR]

ABSTRACT Microencapsulated aluminum hypophosphite (MFAHP) with a shell of melamine-formaldehyde resin (MF) was prepared via in situ condensation polymerization. The presence of MFAHP increased the water resistance of flame-retarded (FR) acrylonitrile-butadiene-styrene (ABS) composites after hot water treatment. The mechanical properties indicate that the tensile strength and flexural strength of the FR ABS/MFAHP composites is enhanced with the incorporation of MFAHP. Cone calorimeter test results demonstrated that the peak heat release rate, total heat release, and total smoke release values of the ABS/MFAHP composites were significantly decreased. Digital photos and scanning electron microscopy images of the residues of ABS/25 wt % MFAHP2 composites exhibited compact char layer structures, with many cobweb-like nanoparticle arrangements formed on the surface by the burning process. The investigation of flame-retardant mechanisms of ABS/MFAHP composites using infrared spectroscopy and energy-dispersive X-ray spectroscopy indicated that both the formation of char residue in the condensed phase and the release of inert gases by the MF shell in the gas phase led to the formation of compact and stable char layers containing carbon/pyrophosphate and aluminum polyphosphate, consequently leading to the good flame-retardant performance of MFAHP. © 2017 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2017, 134, 45008. [ABSTRACT FROM AUTHOR]

The results of examination of the influence of ageing by UV rays on the gloss, color, and morphology of injection molded parts made of ABS terpolymer with addition of coloring agents in the form of powder and its masterbatch (granulate) based on ABS and PS media are presented in this article. It has been shown that the UV radiation contributes to decrease in the value of gloss and increase in the luminance of moldings and also changes values of parameters a and b, describing the change in parts color, in the direction of red and yellow, which is connected with the degradation of polymer ABS and coloring agents. Ageing process leads to structural changes in polymer, depending on the type of coloring agent. © 2015 Wiley Periodicals, Inc. Col Res Appl, 41, 392-398, 2016 [ABSTRACT FROM AUTHOR]

In this paper, a facile method is introduced to modify melamine phosphate ( MP) via the sol-gel process. The aim was simultaneously to increase the water resistance of MP and improve the dispersion and compatibility of MP in acrylonitrile-butadiene-styrene copolymer ( ABS). In addition, the incorporation of SiO2 particles into the MP/dipentaerythritol ( DPER) system can further ameliorate the char-forming ability and enhance the flame retardant properties of polymer composites. The chemical structure and surface morphology of SiO2@ MP were confirmed and observed by Fourier transform infrared ( FTIR) spectroscopy, SEM and TEM, respectively. The results demonstrate that ABS/ SiO2@ MP/ DPER (3/1) at a loading of 30 phr reaches 31.2% limiting oxygen index and achieves a UL-94 V-0 rating. Moreover, FTIR spectra indicate that the main char-forming process of the SiO2@ MP/ DPER system occurs at 365-420 °C. A potential condensed flame retardant mechanism of SiO2@ MP and DPER in ABS composites is proposed via the systematic analysis of char residue after combustion by FTIR spectroscopy, SEM and X-ray photoelectron spectroscopy. © 2015 Society of Chemical Industry [ABSTRACT FROM AUTHOR]

In orally acquired bacteria, the ability to counteract extreme acid stress (pH ⩽ 2.5) ensures survival during transit through the animal host stomach. In several neutralophilic bacteria, the glutamate-dependent acid resistance system (GDAR) is the most efficient molecular system in conferring protection from acid stress. In Escherichia coli its structural components are either of the two glutamate decarboxylase isoforms (GadA, GadB) and the antiporter, GadC, which imports glutamate and exports γ-aminobutyrate, the decarboxylation product. The system works by consuming protons intracellularly, as part of the decarboxylation reaction, and exporting positive charges via the antiporter. Herein, biochemical and spectroscopic properties of GadB from Brucella microti ( Bm GadB), a Brucella species which possesses GDAR, are described. B. microti belongs to a group of lately described and atypical brucellae that possess functional gadB and gadC genes, unlike the most well-known “classical” Brucella species, which include important human pathogens. Bm GadB is hexameric at acidic pH. The pH-dependent spectroscopic properties and activity profile, combined with in silico sequence comparison with E. coli GadB ( Ec GadB), suggest that Bm GadB has the necessary structural requirements for the binding of activating chloride ions at acidic pH and for the closure of its active site at neutral pH. On the contrary, cellular localization analysis, corroborated by sequence inspection, suggests that Bm GadB does not undergo membrane recruitment at acidic pH, which was observed in Ec GadB. The comparison of GadB from evolutionary distant microorganisms suggests that for this enzyme to be functional in GDAR some structural features must be preserved. [ABSTRACT FROM AUTHOR]

Blends of recycled polycarbonate ( PC) and acrylonitrile-butadiene-styrene ( ABS) were prepared and some mechanical and morphological properties were investigated. To compatibilize these blends, ABS- g-(maleic anhydride) ( ABS- g- MA) and (ethylene-vinyl acetate)- g-(maleic anhydride) ( EVA- g- MA) with similar degree of grafting of 1.5% were used. To compare the effect of the type of compatibilizer on mechanical properties, blends were prepared using 3, 5 and 10 phr of each compatibilizer. A co-rotating twin-screw extruder was used for blending. The results showed that ABS- g- MA had no significant effect on the tensile strength of the blends while EVA- g- MA decreased the tensile strength, the maximum decrease being about 9.6% when using 10 phr of this compatibilizer. The results of notched Charpy impact strength tests showed that EVA- g- MA increased the impact strength of blends more than ABS- g- MA. The maximum value of this increase occurred when using 5 phr of each compatibilizer, it being about 54% for ABS- g- MA and 165% for EVA- g- MA. Scanning electron microscopy micrographs showed that the particle size of the dispersed phase was decreased in the continuous phase of PC by using the compatibilizers. Moreover, a blend without compatibilizer showed brittle behaviour while the blends containing compatibilizer showed ductile behaviour in fracture. © 2013 Society of Chemical Industry [ABSTRACT FROM AUTHOR]

ABSTRACT Because zinc borate is an effective smoke suppressant and cheaper than antimony trioxide, the main aim of this study was to investigate usability of zinc borate as the third component of a traditional binary Br/Sb2O3 system in acrylonitrile butadiene styrene. Limiting oxygen index, UL-94, and mass loss cone calorimeter studies indicated that almost all flame retardancy parameters were kept when certain percentages of antimony trioxide were replaced with zinc borate. Residue analysis revealed that the predominant flame retardancy mechanism of the traditional system was gas phase action, whereas zinc borate contributes especially in the condensed phase action by forming thicker and stronger char layer. Copyright © 2012 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

ABSTRACT As a large number of corpuses are represented, stored and published in XML format, how to find useful information from XML databases has become an increasingly important issue. Keyword search enables web users to easily access XML data without the need to learn a structured query language or to study complex data schemas. Most existing indexing strategies for XML keyword search are based upon Dewey encoding. In this paper, we proposed a new encoding method called Level Order and Father (LAF) for XML documents. With LAF encoding, we devised a new index structure, called two-layer LAF inverted index, which can greatly decrease the space complexity compared with Dewey encoding-based inverted index. Furthermore, with two-layer LAF inverted index, we proposed a new keyword query algorithm called Algorithm based on Binary Search (ABS) that can quickly find all Smallest Lowest Common Ancestor. We experimentally evaluate two-layer LAF inverted index and ABS algorithm on four real XML data sets selected from Wikipedia. The experimental results prove the advantages of our index method and querying algorithm. The space consumed by two-layer LAF index is less than half of that consumed by Dewey inverted index. Moreover, ABS is about one to two orders of magnitude faster than the classic Stack algorithm. Concurrency and Computation: Practice and Experience, 2012.© 2012 Wiley Periodicals, Inc. [ABSTRACT FROM AUTHOR]

ABSTRACT In order to improve permeability and selectivity of membranes, especially for gas separation applications, a mixed matrix membrane was prepared from acrylonitrile butadiene styrene (ABS) and cadmium sulfide (CdS) nanoparticles with 1, 1.5, 2.5 %wt. Gas permeation and separation characteristics of the membranes for nitrogen, methane, carbon dioxide and helium have been studied. Scanning electron microscopy and X-ray diffraction analysis were also utilized in nanoparticles and membranes characterizations. The results showed an increase in permeability for mixed matrix membranes in comparison with neat ABS membrane. Furthermore, as the nanoparticle content increased, membrane gas permeability was enhanced. The selectivity for (CO2/CH4), (CO2/N2) and (He/CH4) initially were increased by increasing CdS nanoparticle concentration up to 1 %wt in the prepared membrane and then began to decrease with more additives loading. The membrane with 2.5 %wt CdS nanoparticle content showed the highest permeability compared with others. Also, the membrane with 2.5 %wt CdS nanoparticles showed appropriate selectivity compared with the neat ABS membranes. Obtained results revealed that membranes with 1 %wt CdS nanoparticle content had the best selectivity for (CO2/CH4), (CO2/N2) and (He/CH4). Moreover, membrane thermal stability was improved in the presence of cadmium sulfide nanoparticles. © 2012 Curtin University of Technology and John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

Aim Sacral neuromodulation (SNM) plays a major part in the algorithm of management of faecal incontinence, but there are limited data on its cost-effectiveness. This study aimed to analyse this and the quality-adjusted life-years (QALYs) associated with two different treatment algorithms. The first (SNM−) included use of an artificial sphincter [dynamic graciloplasty (DGP) (50%) and artificial bowel sphincter (ABS) (50%)]. The second (SNM+) included SNM (80% of cases) and artificial sphincter (DGP 10%; ABS 10%) The incidence of sphincteroplasty was assumed to be equal in both algorithms. Method A Markov model was developed. A hypothetical cohort of patients was run through both strategies of the model. A mailed EuroQoL-5D questionnaire was used to determine health-related quality of life. Costs were reproduced from the Maastricht University Medical Centre prospective faecal incontinence database. The time scale of the analysis was 5 years. Results The former treatment protocol cost €22 651 per patient and the latter, after the introduction of SNM, cost €16 473 per patient. The former treatment protocol resulted in a success rate of 0.59 after 5 years, whereas with the introduction of SNM this was 0.82. Adhering to the former treatment protocol yielded 4.14 QALYs and implementing the latter produced 4.21 QALYs. Conclusion The study demonstrated that introducing SNM in the surgical management algorithm for faecal incontinence was both more effective and less costly than DGP or ABS without SNM. This justifies adequate funding for SNM for patients with faecal incontinence. [ABSTRACT FROM AUTHOR]

Summary: In this work, blends of ABS and PC with various compositions were processed by melt compounding in a twin screw extruder and the obtained samples were studied in terms of structure and thermomechanical properties. The effect of incorporation of organically modified montmorillonite (OMMT) nanoparticles on the above properties was also investigated. The addition of PC improves the thermal degradation resistance and tensile properties of ABS. The incorporation of OMMT into ABS/PC mixtures alters the thermal degradation mechanism for blends containing more than 50% PC and further improves the tensile properties and especially the modulus of elasticity. [ABSTRACT FROM AUTHOR]

Summary: In this work, poly(acrylonitrile-butadiene-styrene) (ABS) and different organically modified montmorillonite clay nanocomposites were prepared by melt intercalation in a co-rotating twin screw extruder. The influence of the screw torque during processing and of the mixture of the modified organoclays in the intercalation/exfoliation of the clay in the polymeric matrix was evaluated through low angle X-ray diffraction range and capillary and parallel plate-plate rheometry. [ABSTRACT FROM AUTHOR]

Uniform monodisperse FeOOH and hematite (Fe2O3) nanoparticles were synthesized at room temperature via a facile sonochemical reaction between FeCl3 and NaOH. Fe2O3 nanoparticles were then added to acrylonitrile-butadiene-styrene (ABS) polymer. Nanoparticles and nanocomposites were characterized using X-ray diffraction, scanning electron microscopy, Fourier transform infrared, and photoluminescence (PL) spectroscopy techniques. The effect of the presence of FeOOH and Fe2O3 nanoparticles in the polymer matrix on the thermal properties was studied using thermogravimetric analysis and derivative thermogravimetric analysis, in both air and nitrogen atmospheres. The magnetic properties of the samples were also investigated using an alternating gradient force magnetometer. We found that the Fe2O3 nanoparticles exhibit a ferromagnetic behavior with a saturation magnetization of 0.869 emu/g and a coercivity of 191 Oe at room temperature. The coercivity of ABS/ Fe2O3 (5%) nanocomposites is found to be 252 Oe, higher than 226 Oe which is obtained for ABS/Fe2O3 (20%). © 2012 Wiley Periodicals, Inc. J Appl Polym Sci, 2012 [ABSTRACT FROM AUTHOR]

The aim of this article was to study the microstructure development and the linear melt viscoelastic properties of ABS/MWNT nanocomposites. The nanocomposite samples varying in nanotube concentration (1, 2, 4, and 8 wt %) were prepared using two different methods; solution method and direct melt compounding. Results of the melt linear viscoelastic measurements performed on the nanocomposite samples prepared by both methods showed a pronounced low frequency nonterminal behavior in storage modulus along with the viscosity upturn with greater extent for the samples prepared by the solution method. The values of low frequency storage modulus for the solution processed samples were found to be increased with increasing the nanotube content up to 3 wt % above which it is increased more significantly. These results could be related to a 3D microstructure development, the extent of which was found to be enhanced in the samples prepared by the solution method due to the improving interfacial interaction and promoting the nanotube dispersion in ABS matrix. This was supported by the SEM results of the samples. Dynamic mechanical thermal analysis results of the melt-mixed and solution-processed samples showed that Tg of the SAN is increased about 20°C at the presence of nanotube. The results are related to the chain mobility restrictions caused by physical interaction between carbon nanotubes (CNT) and polymer chains. The electrical conductivity versus CNT content for the nanocomposite samples prepared by solution method showed a percolation behavior with CNT concentration above 4 wt % which attributed to the 3D network between nanotubes. © 2012 Wiley Periodicals, Inc. J Appl Polym Sci, 2012 [ABSTRACT FROM AUTHOR]

UV-curable fluorinated organic-inorganic hybrid coatings were prepared by the sol-gel technique. Perfluorinated urethane modified alkoxysilane was synthesized by the reaction between perfluoro alcohol and 3-isocyanatopropyltrimethoxysilane. The prepared formulations were applied onto poly(methyl methacrylate) (PMMA) and acrylonitrile butadiene styrene (ABS) panels and polymerized by UV-curing. The properties of the hybrid coatings such as hardness, chemical resistance, thermal stability, surface morphology, double bond conversion, and also contact angle measurements were investigated. Contact angle measurements have shown that the addition of fluorinated silane precursor to the hybrid system improved the water repellency and increased the contact angle from 65° to 106°. Copyright © 2009 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

Various analogos of phosphonic acid, phosphinic acid, and CHP(O) group containing organo-phosphorus compounds were synthesized as model compounds to investigate the effects of P content and the structure of flame retardant (FR) on their fire retarding performances of acrylonitrile-butadiene-styrene (ABS) and ethylene-vinyl acetate (EVA) copolymer. The success of synthesis was confirmed by H- and P-NMR. The flame retarding efficiencies were evaluated by a UL-94 vertical test method. Thermogravimetric analysis results reveal that all the mixtures of FRs with ABS or EVA exhibit no or very little charred residues at 600°C under inert atmosphere condition, indicating that all FRs work in the gas phase rather than in the condensed phase for both ABS and EVA. The fire retarding efficiency of FR depends not only on the P content in FR but also on the nature of its structure. UL-94 results show that P FRs with CH group attached to the P atom exhibits the best fire retarding performance on both ABS and EVA. It was found that at least 4 wt% P in the formulation is required to show self-extinguishing ability for both ABS and EVA when P FRs having CH group are employed. The fire retarding efficiency of P FRs with different attached group is in order of: CH > CH > OH > H. Copyright © 2009 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

Copyright of Canadian Journal of Chemical Engineering is the property of Wiley-Blackwell and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Infections may act as environmental triggers for the induction of systemic lupus erythematosus (SLE). In this study, we determine the relationship between disease manifestations of SLE patients and the titers of five Epstein–Barr virus (EBV) Abs. We evaluated the titers of early antigen IgG (EAG), nuclear antigen IgG, viral capsid antigen (VCA) IgG and IgM, and heterophile IgM, using the BioPlex 2200 multiplexed immunoassay method in 260 sera (120 SLE patients and 140 controls). EAG titers were significantly elevated ( P < 0.024) in patients with cutaneous symptoms and increased anti-Ro antibody titers ( P < 0.005). VCA IgG titers were significantly elevated ( P < 0.003) in patients with joint involvement. None of the titers differed by central nervous system or renal involvement or antiphospholipid syndrome. We conclude that exposure to EBV infection may predict a disease phenotype of mild SLE disease with cutaneous and joint manifestations and elevated titers of anti-Ro Abs. [ABSTRACT FROM AUTHOR]

Copyright of Canadian Journal of Chemical Engineering is the property of Wiley-Blackwell and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Surfactants are the single most important ingredients in laundry and household cleaning products, comprising from 15 to 40% of the total detergent formulation. They play a key role in the $60 billion detergent market, which is the focus of this review. The past, present, and future trends of mainframe anionic surfactants and the key technological developments for these surfactants are discussed. The focus of this review is on how surfactants are changed (i) to meet changing environmental requirements, (ii) to take advantage of advances in process technology, and (iii) to address changes in consumer habits. [ABSTRACT FROM AUTHOR]

A joint cell range expansion (CRE) and enhanced inter‐cell interference coordination (eICIC) scheme is proposed to enhance the capacity of two‐tier heterogeneous networks. Optimal CRE bias and almost blank subframe ratio solutions are achieved by considering the fairness of users at the centre and cell edge. Capacity improvement is verified through extended results. [ABSTRACT FROM AUTHOR]

Chrome‐plated acrylonitrile–butadiene–styrene (ABS) parts with defects in the metal layer were submitted to pickling with hydrochloric and nitric acids and recycled by injection in different proportions with neat ABS. For comparison, samples with neat ABS (ABSn) and ABS submitted to pickling (ABSp) were also injected. The influence of the pickled material on the samples properties was evaluated by chemical, thermal, and mechanical analysis. The injected samples were chrome by conventional process and evaluated by visual inspection, adhesion test, resistance to corrosion, and accelerated aging test, to evaluate the quality of the chrome finish. A gradual darkening of samples and formation of carbonyl groups with the increase in the pickled ABS concentration and little influence on the melt flow index were observed. The samples exhibited one thermal degradation stage similar to ABSn. The increase in the pickled ABS percentage caused a slight increase in glass‐transition temperature of polybutadiene phase, and did not influence the tensile properties and hardness of samples, but decreased the impact resistance. After chrome plating, all samples were approved for visual inspection and metal layer adhesion test. Only the sample injected with pickled ABS was reproved in corrosion test, due to the oxidation of the chrome layer. © 2019 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2020, 137, 48372. [ABSTRACT FROM AUTHOR]

In this study, we focus our attention on the impact of ozone (O3) and ultraviolet radiation (UV) on materials usable for three‐dimensional (3D) printing. Specifically, we have studied the potential degradative effect on the most commonly used filaments, such as polylactic acid (PLA) and acrylonitrile–butadiene–styrene (ABS). The effect has been examined on objects printed on a 3D printer and on the materials of discharge chambers of O3 generators from which they were printed. For the purpose of adequate assessment of the actual impact of O3 and UV, samples were monitored for a period of 18‐hr of exposure. The methods of Raman spectroscopy, optical and scanning electron microscopy and Fourier‐transform infrared spectroscopy (FTIR) have been employed for an objective evaluation of potential modifications. A generator equipped with a chamber printed from a new PLA filament and an active electrode system in the form of a stripes electrode, or more precisely, in the second case, a honeycomb‐active electrode, both cut out of a thin copper foil, was used for the generation of O3 and UV radiation. The tested materials showed substantial resistance to O3 exposure under the test conditions. The result of measurements suggested that these materials could be used for chambers for the O3 as well as for active particle generation. [ABSTRACT FROM AUTHOR]

Composites based on graphite‐reinforced acrylonitrile‐butadiene‐styrene (ABS) polymer matrix are prepared in compositions of 1 and 2 wt% of graphite and the mechanical properties are compared to the neat ABS. The specimens are prepared by melt mechanical mixing through an intensive homogenizer/mixer followed by the hydropneumatic press. The materials are characterized by Charpy impact strength, Shore D hardness, and optical microscopy. Results shows that the ABS impact strength decreased (reduction of 33% with only 1 wt% of graphite) with the increase of the graphite content in the compositions, the addition of highly rigid graphite in the ABS matrix altered the tenacity mechanism. In addition, there was a 12% increase in the hardness of the composites in relation to the neat ABS. Microscopic analysis shows the presence of small graphite particles well distributed in the polymer matrix. [ABSTRACT FROM AUTHOR]