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Viscoelastic phase separation (VPS) is a fundamental physical phenomenon that creates percolated network structure in dynamically asymmetric mixtures. The object of this study was to investigate the effect of rod shape nanoparticies with different surface chemistries on VPS in the polystyrene/poly(vinyl methyl ether), PS/PVME, blend. For this purpose, hydrophilic (CNWs) and hydrophobic (M-CNWs) cellulose nanowhiskers (CNWs) were prepared to be used as nanorods. Rheological measurments were employed to investigate the effect of nanowhiskers on phase separation temperature, kinetics of phase separation, and dynamic asymmetry. The evolution of morphology during the phase separation at a fixed quench depth was assessed using polarized optical microscopy. The nanowhiskers were effective in decreasing the correlation length, which slowed down the phase separation. CNWs self-assembled into the PVME-rich phase during the phase separation, which led to a decrease in the dynamic asymmetry and beyond a critical volume fraction of CNWs, the VPS mechanism changed to spinodal decomposition (SD). However, in the presence of M-CNW, the localization of M-CNWs into the PS-rich phase enhanced the dynamic asymmetry and at 2 vol% M-CNWs, the induced PS-rich network by VPS was arrested. The linear and non-linear viscoelastic behavior of the samples were Studied as well. POLYM. ENG. SCI., 58:920-942, 2018. [C] 2017 Society of Plastics Engineers, INTRODUCTION Phase separation in polymer blends is of scientific and practical interest as different mechanisms of phase separation yield different morphologies which are related to various functions associated with electrical, [...]

Semi-permeable membranes of binary polymer blends of cellulose triacetate (CTA) and chitosan (CS) were produced to harvest microalgal biomass for biofuels. Relatively thick membranes of polymer blends containing more than 70% CTA were prepared via solution blending in formic acid. Various characterization methods revealed that both polymers are immiscible at the molecular level at room temperature. However, they were macroscopically compatible and exhibited uniform physical properties due to the molecular interactions between CTA and CS with the same cellulosic backbone containing two linear polysaccharides through a [beta]-1,4 glycoside bond. Careful visual inspection revealed that these membranes are transparent and their light transmittance was greater than 90% at all blend compositions. All membranes showed excellent tensile strength at all compositions and the maximum tensile strength was 52.4 MP from the membrane with a CTA/CS weight ratio of 9:1. The NOJ permeability of these blend films increased with increasing CS content and the maximum value was 44.28 mg/[m.sup.2]/day. To improve the NO3 permeability or transfer rate of the CTA/CS membranes, the porous CTA/CS membranes were also prepared using various amounts of silica nanoparticles., INTRODUCTION Production of liquid fuels from a variety of biomasses has recently attracted a great deal of interest from the fuel industry. Microalgae comprise one of the most promising sources [...]

Lignin is a polyphenolic polymer which is naturally synthesized in lignocellulosic biomass. This polymer is linked to cellulose and hemicellulose and provides the structural integrity of the cell wall. The [...]

A novel, ultra low-cost surface enhanced Raman spectroscopy (SERS) substrate has been developed by modifying the surface chemistry of cellulose paper and patterning nanoparticle arrays, all with a consumer inkjet printer. Micro/nanofabrication of SERS substrates for on-chip chemical and biomolecular analysis has been under intense investigation. However, the high cost of producing these substrates and the limited shelf life severely limit their use, especially for routine laboratory analysis and for point-of-sample analysis in the field. Paper-based microfluidic biosensing systems have shown great potential as low-cost disposable analysis tools. In this work, this concept is extended to SERS-based detection. Using an inexpensive consumer inkjet printer, cellulose paper substrates are modified to be hydrophobic in the sensing regions. Synthesized silver nanoparticles are printed onto this hydrophobic paper substrate with microscale precision to form sensing arrays. The hydrophobic surface prevents the aqueous sample from spreading throughout the paper and thus concentrates the analyte within the sensing region. A SERS fingerprint signal for Rhodamine 6G dye was observed for samples with as low as 10 femtomoles of analyte in a total sample volume of 1 [micro]L. This extraordinarily simple technique can be used to construct SERS microarrays immediately before sample analysis, enabling ultra low-cost chemical and biomolecular detection in the lab as well as in the field at the point of sample collection. 10.1021/ac102475k

Biochars produced by slow pyrolysis of greenwaste (GW), poultry litter (PL), papermill waste (PS), and biosolids (BS) were shown to reduce [N.sub.2]O emissions from an acidic Ferrosol. Similar reductions were observed for the untreated GW feedstock. Soil was amended with biochar or feedstock giving application rates of 1 and 5%. Following an initial incubation, nitrogen (N) was added at 165 kg/ha as urea. Microcosms were again incubated before being brought to 100% water-filled porosity and held at this water content for a further 47 days. The flooding phase accounted for the majority ( Additional keywords: nitrous oxide, soil properties, biochar, greenwaste, poultry litter, biosolids, papermill, slow pyrolysis, mechanism., Introduction Nitrous oxide ([N.sub.2]O) is a potent greenhouse gas with global warming potential 298 times greater than the equivalent mass of C[O.sub.2] in the atmosphere (Forster et al. 2007). It [...]

The study of enzymatic reactions through fluorescence spectroscopy requires the use of bright, functional fluorescent molecules. In the case of proteins, labeling with fluorescent dyes has been carried out through covalent reactions with specific amino acids. However, these reactions are probabilistic and can yield mixtures of unlabeled and labeled enzymes with catalytic activities that can be modified by the addition of fluorophores. To have meaningful interpretations of results from the study of labeled enzymes, it is then necessary to reduce the variability in physical, chemical, and biological characteristics of the labeled products. In this paper, a solid phase labeling protocol is described as an advantageous alternative to free solution labeling of cellulose-binding proteins and is applied to tag cellulases with three different fluorophores. The products from the labeling reactions were purified to remove the unreacted dye and separate labeled and unlabeled enzymes. Characterization of the catalytic and spectroscopic properties of the isolated labeled species confirmed that highly homogeneous populations of labeled cellulases can be achieved. The protocol for the separation of labeled products is applicable to any mixture of labeled proteins, making this an attractive methodology for the production of labeled proteins suitable for single molecule fluorescence spectroscopy.

In all land plants, cellulose is synthesized from hexameric plasma membrane complexes. Indirect evidence suggests that in vascular plants the complexes involved in primary wall synthesis contain three distinct cellulose synthase catalytic subunits (CESAs). In this study, we show that CESA3 and CESA6 fused to GFP are expressed in the same cells and at the same time in the hypocotyl of etiolated seedlings and migrate with comparable velocities along linear trajectories at the cell surface. We also show that CESA3 and CESA6 can be coimmunoprecipitated from detergent-solubilized extracts, their protein levels decrease in mutants for either CESA3, CESA6, or CESA1 and CESA3, CESA6 and also CESA1 can physically interact in vivo as shown by bimolecular fluorescence complementation. We also demonstrate that CESA6-related CESA5 and CESA2 are partially, but not completely, redundant with CESA6 and most likely compete with CESA6 for the same position in the cellulose synthesis complex. Using promoter-[beta]-glucuronidase fusions we show that CESA5, CESA6, and CESA2 have distinct overlapping expression patterns in hypocotyl and root corresponding to different stages of cellular development. Together, these data provide evidence for the existence of binding sites for three distinct CESA subunits in primary wall cellulose synthase complexes, with two positions being invariably occupied by CESA1 and CESA3, whereas at least three isoforms compete for the third position. Participation of the latter three isoforms might fine-tune the CESA complexes for the deposition of microfibrils at distinct cellular growth stages.

A new route is described for rapid decrystallization of cellulose without esterification or morphology change on the macrofiber in trifluoroacetic acid (TFA). The esterification of TFA monomers on the external surface of crystalline cellulose, agglomeration of cellulose macrofibrils as well as water released from the esterification reaction has prevented the diffusion rate of TFA into the cellulose crystalline region and decreased the TFA swelling capability at higher temperatures.

The zinc-induced reductive elimination from 5-deoxy-5-iodo derivatives of D-xylose and L-arabinose is carried out in order to study the structural parameters and the presence of [Zn.sup.2+] ions. The complexes between zinc and [Zn.sup.2+] bound carbohydrates are characterized with large stabilization energies, indicating that [Zn.sup.2+] might increase the affinity of the organic compound with the zinc metal surface.

A study of the water-induced ionic charge transport in cellulose is presented. The behavior of this transport in loosely compacted microcrystalline cellulose (MCC) powder is investigated as a function of density utilizing a new type of measurement setup, allowing for dielectric spectroscopy measurement in situ during compaction.

The isolation and characterization of a Clostridium sp. that effectively degrades cellulosic wastes are described. Specific PCR-based monitoring has revealed that strain EBR45 occurred during the high fermentation efficiency period in the original methanogenic sledge and the strain digested office paper in its pure cultivation system with a synthetic medium.

An investigation is conducted by using density functional calculations to study the reactions between Pd and PDCl2 with cellobiose. PD(II) chloride is shown to promote the polymeric chain cleavage and rising rearrangements, whereas Pd is found to insert in to a C-O bond site in the cyclic carbohydrate moiety with binding energies of -0.2 and -0.5 eV at the Cl'-O5' and the O1-(C-1) bonds, respectively.

Two strains of Saccharomyces cerevisiae, one highly tolerant to lignocellulose hydrolysates and the other a laboratory reference strain, are investigated using batch and fed-batch fermentations of hydrolysates, as well as chemostat cultures with synthetic medium. The ability to reduce 5-hydroxy-methyl furfural is important for the development of yeast strains with increased tolerance to lignocellulosic hydrolysates.

Clostridium populations that are responsible for cellulose degradation in a methanogenic landfill leachate bioreactor are identified, detected and their spatial resolution is determined based on their proximity to the cellulose surface, identity and relative abundance. The presence, abundance and spatial arrangements of different microorganisms in the bioreactor were confirmed by Fluorescence in situ hybridization (FISH).

The crystal and molecular structure together with hydrogen bonding system in cellulose Ibeta is determined using synchroton and neutron diffraction data recorded from oriented fibrous samples prepared by aligning cellulose microcrystals from tunicin. The results indicate that the structure of cellulose Ibeta differs from those of cellulose Ialpha.

Byline: G. Reinders (1), H.-P. Thier (1) Keywords: Tomatoes; Methanolysis; Polysaccharides; Pectins; Hemicelluloses Abstract: For analysing the non-starch polysaccharides (NSP) of tomatoes, the alcohol-insoluble solids were fractionated using water, EDTA solution and sodium hydroxide solution, and the sugar and uronic acid components were determined by capillary gas chromatography. Highest yields of monosaccharides were obtained when the pectin and cellulose fractions were treated with methanesulfonic acid prior to methanolysis by diluting with methanol and heating to 100aadegC for 2h. However, treatment with concentrated formic acid followed by methanolic hydrochloric acid was best suited for the hemicellulose fractions. In this way, 81% of total tomato NSP (5.1g/kg fresh weight) were characterized for their monosaccharide pattern. Free and associated pectins amounted to 28%, xyloglucans and other hemicelluloses to 30% and cellulose to 23%. Author Affiliation: (1) Institute of Food Chemistry, University of Munster, Corrensstrasse 45, D-48149 Munster, Germany, DE Article note: Received: 13 July 1998 / Revised version: 23 September 1998