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Novel cross-linked fluorinated acrylate latex was successfully synthesized via the semi-continuous seeded emulsion polymerization, in which methyl methacrylate (MMA) and butyl acrylate (BA) were used as the main monomers, and dodecafluoroheptyl methacrylate (DFMA) and N–N methylene bisacrylamide (MBA) were used as the fluorine monomer and the cross-linked monomer, respectively. Potassium persulfate (KPS) and mixed surfactants of sodium lauryl sulfate and alkyl alcohol polyether (EFS-470) were used as the initiator and emulsifier, respectively. The structure of resultant latex film was characterized by Fourier transform infrared spectroscopy (FTIR). The latex films were tested by thermogravimetric analysis (TGA), differential scanning calorimetry (DSC), contact angle (CA), cross-linked degree and X-ray diffractometer (XRD). The particle size and its distribution of the latex were measured by the nanoparticle size analyzer and transmission electron microscope (TEM). The factors that have an influence on the properties of the latex and the film are investigated in detail. The stability of the resultant latex was good. The average particles of the latex and its distribution were small and uniform, respectively. In comparison with the conventional latex film, the thermal stability and hydrophobicity of the novel latex film were improved obviously. [ABSTRACT FROM AUTHOR]

Chitosan is a polysaccharide resulting from chitin deacetylation. It has demonstrated interesting characteristics in the field of adhesion but loses most of its adhesive resistance in moist environment. A chemical crosslinking of chitosan with genipin has been implemented to improve its adhesive properties in the presence of water. The study of crosslinking kinetics using rheology revealed its dependency on crosslinking rate and chitosan concentration. The capacity of the chitosan-genipin systems for water absorption has been quantified as their Free Swelling Capacity. The cross-linkage of chitosan by genipin (1% w/w) decreased significantly its ability for water absorption. Finally, the adhesive strength of several chitosans be they supplemented or not with genipin and/or glycerol used as plasticizer have been performed on Thick Adherent Shear Test samples of beech wood according to standard EN 204:2016 and EN 205:2016. The chitosan adhesive formulation containing genipin and glycerol exhibits the better adhesive properties on wood and presents higher water resistance compared to the native chitosan formulation. [ABSTRACT FROM AUTHOR]

OpenAerialMap (OAM) is a crowdsourcing platform for uploading, hosting, sharing, displaying, searching, and downloading openly licensed Earth image data from around the world. OAM was launched with the primary goal to facilitate rapid disaster response mapping after natural events, such as floods or hurricanes. Images contributed to OAM can be used as a background layer in OpenStreetMap (OSM) editors to edit map features, such as buildings or facilities, which may have been affected by such events. This study analyzes how the provision of OAM images is associated with changes in underlying editing patterns of OSM features by comparing the number of edited OSM objects between 2 weeks before and 2 weeks after an image has been shared through OAM. The comparison also involves other aspects of OSM editing patterns, including geometry types and OSM primary feature types of edited objects, type of feature editing operations, edits per user, and contribution distribution across continents. Results show that the number of point features added to OSM more than quadrupled within the first 2 weeks after OAM image upload compared to that of 2 weeks before, and that the number of ways added almost doubled. This suggests that the OSM community utilizes provided OAM images for OSM map updates in the respective geographic areas. The study provides a showcase which demonstrates how information from one crowdsourcing platform (OAM) can be used to enhance the data quality of another (OSM) with regards to completeness and timeliness.

Electrospinning of nonwoven nanofibrous mats has received significant attention in recent years due to the high versatility and porosity of electrospun mats. However, electrospun mats generally suffer from low mechanical strength. This work reports a method to improve the mechanical strength of nanofiber mats by coaxial electrospinning combined with thermal treatment, without incurring significant dimensional shrinkage. Coaxial polyacrylonitrile (PAN)/polyvinylidene fluoride‐hexafluoropropylene (PVDF‐HFP) mats showed no shrinkage when tested at temperatures up to 240°C for 20 min, compared to a shrinkage of 94% for the homogenous PVDF‐HFP mats when treated at 190°C for 20 min. When treated at 178°C for up to 30 min, the coaxial fibres consistently showed changes in thickness of less than 10% and no significant change in area. The coaxial PAN/PVDF‐HFP mats showed negligible changes in average porosity after treatment at 178°C for 20 min. The mechanical strength of the coaxial samples heat treated at 178°C for 5 min was 7.72 MPa, a 22% increase from that before heating, and a 54% increase compared to the as‐spun homogenous PVDF‐HFP. Thus, the proposed technique of combining heat treatment with coaxial morphologies demonstrates significant potential for improving mechanical strength without dimensional shrinkage. [ABSTRACT FROM AUTHOR]

The purpose of this study is to determine the rheological properties of cross-linked inulin solutions in two different polymerization degrees (native and degree of polymerization of >23%). Thus, the effect of cross-linking, a new approach applied to support a specific property (stabilization) of inulin, which has many benefits, has been demonstrated. Sodium hexametaphosphate was used as a cross-linking agent at three different ratios (0.375%, 0.500%, and 0.750%). The cross-linked inulin solutions were lyophilized, and the lyophilized mixture was then reconstituted at 25 °C and 45 °C to obtain cross-linked inulin solutions with 1% and 5% (w/v) concentrations. The control samples (native and with a high degree of polymerization) were treated similarly without a cross-linking agent. The samples were subjected to a dynamic frequency sweep test in the range of 0.01–10 Hz as well as shear viscosity measurements at 1–500/s shear rates for the determination of rheological properties. The thixotropic curves were analyzed as the shear rate increased from 0.1/s to 300/s in the first 120 s (up curve), and then decreased to the same point in the subsequent 120 s. Results indicated that cross-linking increased inulin solution viscosity, particularly at 5% concentration, and solubility. Solutions with 5% inulin containing 0.750% and 0.375% cross-linker yielded the highest viscosities at 45 °C and 25 °C, respectively. Samples with 5% inulin concentration exhibited solid-like behavior in the oscillation test. Thixotropic curves revealed antithixotropy at low shear rates and thixotropy at high shear rates. The study demonstrated the impact of cross-linking on inulin stabilization, providing insights for future applications. Results indicated that cross-linking increased inulin solution viscosity, particularly at 5% concentration, and solubility. Solutions with 5% inulin containing 0.750% and 0.375% cross-linker yielded the highest viscosities at 45 °C and 25 °C, respectively. Samples with 5% inulin concentration exhibited solid-like behavior in the oscillation test. Thixotropic curves revealed antithixotropy at low shear rates and thixotropy at high shear rates. The study demonstrated the impact of cross-linking on inulin stabilization, providing insights for future applications. [ABSTRACT FROM AUTHOR]

Simple Summary: Collagen is an important component of muscle tissue that maintains muscle structure and also contributes to meat quality. However, the characteristics of intramuscular connective tissue (IMCT) collagen of Wuzhumuqin sheep are unknown. The purpose of this study was to analyze the characteristics of IMCT collagen in Wuzhumuqin sheep at different growth stages and to determine the correlation between them. The results showed that collagen-related genes were highly expressed at 9 and 12 months of age. The amino acid content, solubility, thermal stability, and degree of cross-linking of collagen were altered by collagen type, muscle type, and age. Multiple patterns of correlation between collagen characteristics are essential for the development of IMCT. These findings will contribute to a better understanding of the relationship between the characteristics of collagen, and also provide a theoretical basis for further studies on the impacts of collagen on meat quality. Intramuscular connective tissue (IMCT) collagen is an important factor in meat quality. This study analyzed the characteristics of type I and III collagen in the IMCT of the semitendinosus (SD) and longissimus dorsi (LD) of Wuzhumuqin sheep at different growth stages (6, 9, 12, and 18 months). Utilizing sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE) and Fourier transform infrared spectroscopy (FTIR), collagen types I and III were successfully isolated and shown to contain an intact triple helix structure. Immunofluorescence revealed that these collagens were located in the endomysium and perimysium. Collagen-related genes were significantly expressed in sheep aged 9 and 12 months. The amino acid content increased with age in type I collagen whereas it decreased in type III collagen. Furthermore, type III collagen contained more hydroxyproline (Hyd) than type I collagen. Differential scanning calorimetry (DSC) revealed that the thermal stability of collagen increased with age, accompanied by a decrease in solubility. Semitendinosus muscle had more collagen cross-linkages than LD muscle due to the high pyridinoline (Pyr) content in the endomysium. Finally, a correlation analysis highlighted the multiple correlations between characteristics in different types of collagen during sheep growth. In summary, the collagen characteristics in the IMCT of sheep were impacted by collagen type, muscle type, and age. Furthermore, the various correlations between these characteristics may play an important role in the development of IMCT. [ABSTRACT FROM AUTHOR]

Antarctic krill is a potential and attractive resource for consumption. However, most Antarctic krill meat is used to produce primary products with low commercial value, with few highly processed products. This study aimed to evaluate and improve the gelling properties of Antarctic krill surimi, with Pacific white shrimp surimi as control. Compared with Pacific white shrimp surimi, the lower β-sheet content and protein aggregation degree had a severe impact on the formation of the gel network of Antarctic krill surimi, which resulted in weaker breaking force, gel strength, and viscoelasticity (p < 0.05). Moreover, water retention capacity and molecular forces had a positive effect on the stability of the gel matrix of shrimp surimi. Thus, the high α-helix/β-sheet ratio, weak intermolecular interactions, and low level of protein network cross-linkage were the main reasons for the poor quality of Antarctic krill surimi. On this basis, the effects of six polysaccharides on the texture properties of Antarctic krill surimi were studied. Chitosan, konjac glucomannan, sodium carboxyl methyl cellulose, and waxy maize starch resulted in no significant improvement in the texture properties of Antarctic krill surimi (p > 0.05). However, the addition of ι-carrageenan (2%) or κ-carrageenan (1~2%) is an effective way to improve the texture properties of Antarctic krill surimi (p < 0.05). These findings will contribute to the development of reconstituted Antarctic krill surimi products with high nutritional quality and the promotion of deep-processing products of Antarctic krill meat. [ABSTRACT FROM AUTHOR]

Intramuscular connective tissue (IMCT) collagen is an important factor in meat quality. This study analyzed the characteristics of type I and III collagen in the IMCT of the semitendinosus (SD) and longissimus dorsi (LD) of Wuzhumuqin sheep at different growth stages (6, 9, 12, and 18 months). Utilizing sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE) and Fourier transform infrared spectroscopy (FTIR), collagen types I and III were successfully isolated and shown to contain an intact triple helix structure. Immunofluorescence revealed that these collagens were located in the endomysium and perimysium. Collagen-related genes were significantly expressed in sheep aged 9 and 12 months. The amino acid content increased with age in type I collagen whereas it decreased in type III collagen. Furthermore, type III collagen contained more hydroxyproline (Hyd) than type I collagen. Differential scanning calorimetry (DSC) revealed that the thermal stability of collagen increased with age, accompanied by a decrease in solubility. Semitendinosus muscle had more collagen cross-linkages than LD muscle due to the high pyridinoline (Pyr) content in the endomysium. Finally, a correlation analysis highlighted the multiple correlations between characteristics in different types of collagen during sheep growth. In summary, the collagen characteristics in the IMCT of sheep were impacted by collagen type, muscle type, and age. Furthermore, the various correlations between these characteristics may play an important role in the development of IMCT.

Antarctic krill is a potential and attractive resource for consumption. However, most Antarctic krill meat is used to produce primary products with low commercial value, with few highly processed products. This study aimed to evaluate and improve the gelling properties of Antarctic krill surimi, with Pacific white shrimp surimi as control. Compared with Pacific white shrimp surimi, the lower β-sheet content and protein aggregation degree had a severe impact on the formation of the gel network of Antarctic krill surimi, which resulted in weaker breaking force, gel strength, and viscoelasticity (p < 0.05). Moreover, water retention capacity and molecular forces had a positive effect on the stability of the gel matrix of shrimp surimi. Thus, the high α-helix/β-sheet ratio, weak intermolecular interactions, and low level of protein network cross-linkage were the main reasons for the poor quality of Antarctic krill surimi. On this basis, the effects of six polysaccharides on the texture properties of Antarctic krill surimi were studied. Chitosan, konjac glucomannan, sodium carboxyl methyl cellulose, and waxy maize starch resulted in no significant improvement in the texture properties of Antarctic krill surimi (p > 0.05). However, the addition of ι-carrageenan (2%) or κ-carrageenan (1~2%) is an effective way to improve the texture properties of Antarctic krill surimi (p < 0.05). These findings will contribute to the development of reconstituted Antarctic krill surimi products with high nutritional quality and the promotion of deep-processing products of Antarctic krill meat.

In this study, electrospun poly(vinyl alcohol) (PVA) microfibre mats incorporated with clove oil (CO) with high water‐stability and water absorption ability were prepared through a heat‐induced in situ cross‐linkage with citric acid (CA). The effects of CA content on the electrospinning solution properties and physical properties of the crosslinked microfibre mats were investigated. The Fourier transform infrared spectroscopy showed that the esterification could occur between hydroxyl groups on the PVA and carboxyl groups on citric acid. The established strong interactions of citric acid and PVA after crosslinking improved the thermal stability, mechanical properties, contact angle, and water stability. The bacterial growth kinetics and the disk diffusion assay proved that the PVA/CA/CO microfibre mats had an obvious inhibitory effect on E. coli and S. aureus. The results showed the PVA/CA/CO microfibre mats would be a promising package material for food products. [ABSTRACT FROM AUTHOR]

[Display omitted] • EGCG@γ-CD-MOF was introduced into thermal-induced gelation as functional additive. • EGCG@γ-CD-MOF underwent a structural collapse from crystal to amorphous. • Sustained release of EGCG avoided excessive crosslinking of myofibrillar proteins. • EGCG@γ-CD-MOF gave an increased phenolic retention in products. Epigallocatechin-3-gallate (EGCG) could demonstrate crosslinking effects on myofibrillar proteins, yet its proneness to self-aggregation could bring excessive crosslinking and water loss within gels, hindering its application as an additive during thermal gelation process. Here, encapsulation with the γ-cyclodextrin metal organic framework (γ-CD-MOF) before the use of EGCG was found to play a dual role: alleviating over-crosslinking of proteins and elevating water retention within gels. Results showed that EGCG got a sustainable release throughout the thermal process due to the gradual fracture of O-K coordinate bounds and structural collapse of γ-CD-MOF. Mechanism insights revealed that the use of EGCG loaded γ-CD-MOF (EGCG@γ-CD-MOF) could regulate formation efficiency on disulfide bounds and promote protonation transition of the amino groups in proteins. Moreover, EGCG@γ-CD-MOF brought a higher retention of phenols within gels through preventing oxidative transformation of phenols towards quinones, which were verified to display a higher affinity towards myosin via molecular calculations. [ABSTRACT FROM AUTHOR]

Highlights • Study of the effect of cation exchange resin cross-linkage on separation efficiency. • Fractionation of a ternary mixture with a cascade of two four-zone SMB processes. • Resin cross-linkage has a strong effect on separation efficiency. • Proper choice of resin cross-linkage significantly improves separation efficiency. • Both process steps should be optimized separately with respect to resin cross-linkage. Abstract In this study, the effect of cation exchange resin cross-linkage (4.8–8.0 wt% of DVB) on separation efficiency in fractionation of a ternary mixture with a two-step cascade simulated moving bed process was investigated experimentally and by simulations. The recovery of betaine and sucrose from sugar beet molasses containing sulfate salts was chosen as a case study. Betaine was recovered in the first step, and sucrose in the second step. Strong effect of cross-linkage on the separation efficiency in both steps was observed. In betaine recovery, the efficiency increased with increasing cross-linkage of the resin due to stronger ion and size exclusion. The increase of cross-linkage from 5.2 wt% to 8.0 wt% increased productivities of betaine and sucrose by 107% and 61%, respectively. Water consumption decreased simultaneously by 50% and 58%, respectively. No separation could be achieved with 4.8 wt% cross-linked resin. In sucrose recovery, the decrease in cross-linkage from 8.0 wt% to 5.2 wt% was found to increase sucrose productivity by 180% and decrease water consumption by 50%. Further decrease of cross-linkage resulted in decreased separation efficiency. The results clearly demonstrate that the proper choice of separation material cross-linkage not only significantly improves the separation efficiency in fractionation of molasses, but also in other relevant separation cases as well. In the case of ternary separations, it is beneficial to optimize the resin cross-linkage for each separation step. [ABSTRACT FROM AUTHOR]

Cell wall is closely related to bacterial robustness and adsorption capacity, playing crucial roles in nisin production in Lactococcus lactis. Peptidoglycan (PG), the essential component of cell wall, is usually modified with MurNAc O-acetylation and GlcNAc N-deacetylation, catalyzed by YvhB and XynD, respectively. In this study, increasing the two modifications in L. lactis F44 improved autolysis resistance by decreasing the susceptibility to PG hydrolases. Furthermore, both modifications were positively associated with overall cross-linkage, contributing to cell wall integrity. The robust cell wall rendered the yvhB/xynD-overexpression strains more acid resistant, leading to the increase of nisin production in fed-batch fermentations by 63.7 and 62.9%, respectively. Importantly, the structural alterations also reduced nisin adsorption capacity, resulting in reduction of nisin loss. More strikingly, the co-overexpression strain displayed the highest nisin production (76.3% higher than F44). Our work provides a novel approach for achieving nisin overproduction via extensive cell wall remodeling. [ABSTRACT FROM AUTHOR]

The objective of this study was to investigate the effect of addition trans glutaminase TG: (0, 20, 40 and 60U/kg retentate) on some chemical, rheological and sensorial characteristics of UF-Ras cheese over ripening period (90 days). Results demonstrated that the moisture and protein contents were significantly higher in TG cheeses than in the control cheese. The rate of proteolysis (WSN/TN, NPN/TN%) in UF-Ras cheeses treated by TG was slightly higher than in the control cheese. Concerning rheological properties, results showed significantly higher values of hardness, gumminess and chewiness than in the control cheese. TG addition had no significant effect on springiness, cohesiveness and adhesiveness values. Textural characteristics of TG cheeses were at the same level as in control cheeses at 60 days of ripening and no significant effect of TG amount was observed. Sensory analysis revealed that no effect of TG on the flavour and appearance scores. The total scores of TG and control cheese did not differ significantly at 90 days of ripening. Overall, the main effect of TG was to modify the rheological parameters and to increase the protein content of the experimental UF-Ras cheese. [ABSTRACT FROM AUTHOR]

Polyvinyl alcohol (PVA) is an extensively used biodegradable polymer including corrosion inhibition, but it fails to withstand long time protection due to water solubility. The present work emphasized an efficient way to transform PVA to hydrophobic nature and further modification for corrosion protection of mild steel (MS). In this backdrop, PVA was blended with varying amounts of the synthesized amine-functionalized graphene oxide (AGO) and then assimilated with the epoxidized linseed oil (ELO). The fabricated composite material was coated on MS surface by the doctor's blade technique, and their adhesion character, roughness, wettability, and sustainability in saline media were confirmed by atomic force microscopy (AFM), contact angle, and electrochemical techniques. The chemical bonding as well as structural interactions of the prepared AGO were ascertained by Fourier-transform infrared (FT-IR), X-ray powder diffraction (XRD), and X-ray photoelectron spectroscopy (XPS) methods. Electrochemical impedance spectroscopy (EIS) measurements of the PVA coatings showed improved Nyquist semicircle diameter by increasing the AGO content, and the potentiometric polarization (PP) data supports the EIS results. The different weight percentages of AGO dispersed PVA/ELO composite coatings revealed enormous changes in their Nyquist, Bode, and phase angle plots. The highest impedance and charge transfer resistance of PVA/ELO-AGO (0.25 wt%) coating are found to be 108.6 Ω cm2 and 4.541 × 108 Ω cm2, respectively. Further, the composite coating was sustained for 20 days in 3.5 wt% NaCl solution showing its enhanced barrier property. This can be ascribed due to the strong cross-linkages in PVA/ELO-AGO that makes it a durable and promising anti-corrosion coating material. [Display omitted] • The corrosive ions penetrate through the PVA polymeric matrix into the metal substrate causing adhesion loss. • The epoxidized linseed oil (ELO), a bio-based plasticizer was employed to crosslink the PVA matrix. • Forging a successful hydrophobic PVA based composite material. • The EIS results validate the excellent anti-corrosion performance of the PVA/ELO-AGO composite. [ABSTRACT FROM AUTHOR]

Recently, graphene oxide (GO) membranes are highly attractive for their exceptional separation performance. However, their sieving characteristics limit GO membranes for some important applications where organics are preferred or organic solvents are employed. In this work, a novel cross-linked graphene (CG) membrane is fabricated through compressing and then reducing a cross-linked GO aerogel. It achieved high-performance of organics separation with high flux (225 L m −2 h −1 ) and purity (>99.98%) even in a cross-flow separation model, where water was intercepted. Deep insight revealed that both the converted surface wettability and the remaining channels in the CG membrane were crucial for the high-performance of organics separation. Beyond that, this CG membrane offers many advantages, such as facile preparation, self-supporting, structural stability and adaptation in harsh acidic/basic/high-temperature conditions, demonstrating its great potential for practical applications. [ABSTRACT FROM AUTHOR]

Purpose – The purpose of this research was to synthesize a novel cross-linked latex copolymerised by butyl acrylate (BA), isobornyl methacrylate (IBOMA), hydroxy propyl methacrylate (HPMA) and dodecafluoroheptyl methacrylate (DFMA). IBOMA is a very useful functional monomer. Its molecular structure not only contains bornyl acetate alkoxy but also includes a double bond, which can be copolymerised with other unsaturated monomers via free radical polymerization. The large nonpolar bicyclic alkyl in bornyl acetate alkoxy offers the polymer chain strong space steric protection, which endows the polymer with some special properties. Design/methodology/approach – The semi-continuous seeded emulsion polymerisation technology was adopted to copolymerise BA, IBOMA, HPMA and DFMA in the water phase, which was initiated with potassium persulfate (KPS) and emulsified with the mixed surfactants of sodium dodecyl sulphate (SDS) and OP-10. Findings – The particle size of the latex decreases with an increase in the amount of IBOMA. All the latexes have good mechanical stability and calcium ion stability. The latex has good film-forming property when the IBOMA amount is controlled moderately. The optimal IBOMA amount is 10.00 g. The thermal stability and water resistance of the film are improved. Practical implications – The latexes can be applied as a binder of coatings and adhesions. Originality/value – The effect of the amount of IBOMA and BA on the properties of the resultant latex and its film were investigated in detail. In comparison with the latexes copolymerised without IBOMA, the novel latex has better thermal stability and water resistance. [ABSTRACT FROM AUTHOR]

Highlights: [•] The cross-linkage effect of cellulose/laponite hybrids was investigated. [•] Rheological measurements demonstrated a sol-to-gel transition triggered by loading of laponite. [•] The cross-linkage effect of cellulose/laponite hybrids was responsible for tensile strength enhancement of composite films. [ABSTRACT FROM AUTHOR]

Purpose: To evaluate the embolic effect and degradability of gelatin microspheres (GMS) using various degrees of cross-linkage and particle sizes in rabbit renal artery embolization. Methods: Four types of GMS were used, as follows: 2 types of cross-linkage and 2 types of particle size. Twenty-four rabbits (6 in each group) were used for the renal artery embolization. Renal angiography was performed before and after embolization of right renal artery. Follow-up renal angiography was performed 2 days ( n = 2), 5 days ( n = 2), and 15 days ( n = 2) after embolization in each group, and then kidneys were removed for histopathological evaluation. Vascular areas of the angiography were measured by Image J software, and the reperfusion rate was calculated. In renal specimens, residual GMS were checked and the degree of degradation was classified according to a 4-point scale. Results: The mean amounts of large- and small-particle-size GMS injected were 15.0 and 34.3 mg, respectively. Tissue necrosis was confirmed in each group; however, no difference was observed among groups. Renal reperfusion was observed more with small GMS than with large GMS. Renal reperfusion was also observed more with low cross-linked GMS than with high cross-linked GMS. In histopathological specimens, large GMS were confirmed in lobar artery, and small GMS were confirmed in lobular artery. Low cross-linked GMS completely degraded 15 days after embolization. In contrast, high cross-linked GMS were persistent 15 days after embolization. Conclusion: Degree of cross-linkage and particle size affected degradability and reperfusion. [ABSTRACT FROM AUTHOR]

Acidized single-wall carbon nanotubes (SWNTs) were fabricated into multilayers with a hyperbranched azobenzene-containing polymeric diazonium salt (PDAS) using the layer-by-layer adsorption technique. The fabrication process, multilayer thickness variation, multilayer surface morphology and the interaction between SWNTs and PDAS were monitored by UV-Vis absorption spectroscopy, optical ellipsometry, Atomic Force Microscopy, Scanning Electron Microscopy and Raman spectroscopy. Moreover, the nanomechanical properties of the multilayer films were measured by nanoindentation. All results show that SWNTs and PDAS can be fabricated into multilayers based on the cooperation of electrostatic absorption and chemical cross-linkage between SWNTs and PDAS. Further, this cooperation endows the SWNT/PDAS multilayer films with outstanding nanomechanical properties. The hardness and modulus are about 2.0GPa and 10.0GPa, respectively. Finally, the SWNT/PDAS multilayer film can be peeled off to be a free-standing film. [ABSTRACT FROM AUTHOR]

The use of the cross-linked marine seaweeds Lessonia nigrescens Bory and Macrocystis integrifolia Bory to remove 2-nitrophenol and 2-chlorophenol from aqueous solutions at room temperature was investigated. The effect of the initial pH, adsorbent dose, and initial concentration of the pollutant were evaluated in batch experiments. The mathematical adsorption models of Langmuir and Freundlich show a mixed adsorptive mechanism of both phenolic compounds by the algae. The calculated parameters demonstrate a high adsorbent to pollutant affinity ratio, indicating the potential effectiveness of these marine seaweeds in the removal of these phenolic compounds from diluted aqueous solutions. [ABSTRACT FROM AUTHOR]

Based on the sheath-core bicomponent composite fibers with modified polystyrene (PS) and the modified polypropylene (PP), composite fibers obtained were further cross-linked and sulphonated with chlorosulphonic acid to produce strong acidic cation ion exchange fibers. The structures of the fibers obtained were characterized using Fourier transform infrared (FT-IR) spectroscopy, differential scanning calorimetry (DSC) etc. The optimal technology of the fibers obtained is discussed. The static absorption capacity of the sheath-core bicomponent composite cation exchange fibers for Zn, Cu was determined. The absorption kinetics and major factors affecting the absorption capacities of Zn, Cu were studied, and its chemical stability and regenerating properties were probed. The results suggest that cation exchange fibers with better mechanical properties and higher exchange capability were obtained. Moreover, this type of ion exchange fiber has good absorption properties and working stability to various metal ions. Hence, they have higher practicability. [ABSTRACT FROM AUTHOR]

Central Asian water planning following international policy recommendations and ‘blue prints’ has caused more harm rather than benefiting local communities. International research has not been sufficient to contribute in practical terms to water and food security. This paper reflects potential factors that limit understanding the complexity of water management in Central Asia. Five factors are identified which prevent cross linking of research across international boundaries and within countries. These are: (1) language, (2) access, (3) wikipediarism, (4) smattering and (5) outdating. To change the situation two factors are still missing – a lost generation of local experts and an internal critical review. [ABSTRACT FROM AUTHOR]

Abstract: Oriental lacquer is the natural resin obtained by tapping lac trees. It hardens into a tough and insoluble film. The extreme hardness and insolubility are some of the most important functions, which are required for industrial coating materials. In this study, two kinds of oriental lacquer films, traditionally named Kiurushi (raw urushi) and Kuromeurushi produced by two different pretreatments, were analyzed during hardening with Fourier transform infrared spectroscopy (FT-IR), thermogravimetry/differential thermal analysis–mass spectrometry (TG/DTA–MS) and pyrolysis–gas chromatography/mass spectrometry (Py–GC/MS) to investigate their functional expression process. Typical functional groups of the lacquer films were detected by FT-IR. The TG/DTA–MS curves clarified that the thermal degradation of the lacquer films gradually began at around 200°C, and reached the fastest rate at 400–500°C. Apparently, FT-IR and TG/DTA–MS could not reveal any difference between the films. On the other hand, Py–GC/MS revealed differences between the films in the peak area ratios of 3-pentadecenylcatechol to 3-pentadecylcatechol and 3-pentadecadienylcatechol to 3-pentadecylcatechol. The ratios of Kiurushi lacquer film were higher than those of Kuromeurushi lacquer film. Both ratios, furthermore, decreased during hardening due to polymerization of the alkenylcatechols into an urushiol polymer skeleton comprising nucleus–side chain and side chain–side chain cross-linkages with 3-pentadecylcatechol at the terminal. The present results suggest that the reaction rate of these cross-linkages in Kuromeurushi lacquer film is faster than that in Kiurushi lacquer film. A good correlation was found between the peak area ratios obtained by Py–GC/MS and hardness obtained by pencil hardening testing. Oriental lacquer expresses the functions – an extreme hardness and insolubility – accelerating the nucleus–side chain and side chain–side chain cross-linkages. Furthermore, it has become clear that the traditional treatments called Nayashi and Kurome effectively accelerate the hardening rate by activating the cross-linkages. [Copyright &y& Elsevier]

A modified cashew nut shell oil coating film (CNSO-CF) was produced from the biomass of the oil obtained from the nut of Anacardium occidentale Linn . It dries more quickly than the conventional CNSO-CF. It is, therefore, more suitable to mass production on assembly lines. The modified CNSO-CF was analyzed by pyrolysis-gas chromatography/mass spectrometry (Py-GC/MS), and its structures were compared with those of the conventional CNSO-CF and of urethane coating film. It was found that the modified CNSO-CF had a urethane coupling structure in addition to the same structures as the conventional CNSO-CF: the methylene cross-linked and autoxidative side chain-side chain C─C coupling structures. The addition of the urethane coupling structure accelerates the drying rate and expresses the most important functions for industrial use – extreme hardness and insolubility. [ABSTRACT FROM AUTHOR]

The hydroxyapatite (HAp)/gelatin (GEL) nanocomposite was prepared through the coprecipitation and then cross-linked by using glutaraldehyde (GA). From FT-IR measurement the spectral features for amide bands and phosphate bands were severely modified by the cross-linkage and the organic content increased with the degree of cross-linkage. From Transmission Electron Microscopy (TEM) and electron diffraction analyses we could confirm the preferentially directional growth of needle-like HAp particles, which were embedded in GEL by the mineralization. Also we could observe worm-like stria patterns of contrast, which were revealed by the mineralization on the individual GEL fibrils. Moire´ images were observed in a highly cross-linked HAp/GEL nanocomposite sample and we think the cross-linkage induced the assembly of unordered individual fibrils along the preferential direction. [Copyright &y& Elsevier]

A well-defined bovine polyhemoglobin was prepared by dimethyl adipimidate (DMA) and glutaraldehyde double cross-linkage method. DMA was used to block some amino groups of hemoglobin, followed by further polymerization with glutaraldehyde. The amino modification degree of hemoglobin was 32% when DMA reacted with hemoglobin at the molar ratio of 200. The bovine polyhemoglobin with narrow molecular weight distribution (mainly 128 kDa) was obtained when glutaraldehyde reacted with DMA-modified hemoglobin. The P50 and the Hill coefficient for DMA-modified hemoglobin were 19.4 mm Hg and 2.28, respectively, while those for the bovine polyhemoglobin were 15.1 mm Hg and 1.70, respectively. The number of Bohr protons released for DMA-modified hemoglobin and the polyhemoglobin was 0.86 and 0.56 H/tetramer, respectively. [Copyright &y& Elsevier]

Attempts to correlate differences in cell shape with aspects of peptidoglycan structure were investigated. The parent strain, Bacillus subtilis 168, and its temperature-sensitive tagB mutant were grown in the chemostat under different growth conditions. The composition of the peptidoglycan was similar in all samples, regardless of cellular shape and anionic polymer content. Muropeptides, released by digestion with muramidase, comprised mainly dimers and monomers with only small amounts of trimer and traces of tetramer muropeptide. Overall, cross-linking did not vary greatly and the cross-linking index was less than 38%. Reverse-phase HPLC separation showed a complex fine structure. The principal muropeptides in all samples appeared to be the tetra monomer, tetra-tetra dimer and tetra-tetra-tetra trimer. While the major components looked the same in all samples, two specific components, a monomer and a dimer, were seen exclusively in the samples that had coccal morphology. [ABSTRACT FROM AUTHOR]

This study aimed to compare heat-induced gelation in Litopenaeus vannamei and Alaska pollock surimi. Gelation differs in shrimp surimi and surimi upon heating. Texture profile analysis revealed that the shrimp surimi was more elastic and harder than surimi. Frequency and creep and recovery tests indicated that the differences in gelation account for the higher levels of cross-linkage, elasticity, and hardness in shrimp surimi than in surimi. The temperature sweep test revealed two peaks for the shrimp surimi curve and only one peak for the surimi curve in response to heat treatment, representing protein denaturation peaks. Gel electrophoresis revealed that paramyosin (PM) is primarily responsible for these differences and the two peaks in the temperature sweep. Furthermore, the β-sheet content increased in both heated shrimp surimi and surimi in comparison with unheated groups, according to Fourier transform infrared spectroscopy. However, the α-helix content increased in shrimp surimi but decreased in surimi relative to the unheated groups. Therefore, gelation differed between the two materials, and the shrimp surimi structure was more stable than that of surimi. Scanning electron microscopy revealed the post-heating microstructure of shrimp surimi was denser than that of surimi. Fractal dimension calculations confirmed that shrimp surimi gel has a higher degree of cross-linkage than surimi gel because of paramyosin. These findings helped elucidate the heat-induced gelation process in shrimp surimi and develop more products in accordance with the features of shrimp surimi. Image 1 • Paramyosin in shrimp and other crustaceans confers superior gelling in surimi. • Relatively higher β-sheet and α-helix content in shrimp surimi make it dense. • Shrimp surimi has greater viscoelasticity than fish surimi due to its PM content. [ABSTRACT FROM AUTHOR]