Effects of In-Situ Filler Loading vs. Conventional Filler and the Use of Retention-Related Additives on Properties of Paper.

In the present paper, aspects concerning the obtained and characterization of additive systems used for maximizing filler retention, and the effects on paper properties, were investigated. The effects of retention additives over properties of paper, containing fibers from in-situ loading (IS-CCP), were analyzed against the effects of additives over properties of paper containing fibers from conventional loading, obtained by the addition of calcium carbonate in precipitated form (CCP). The physico-mechanical properties were analyzed by various analyses and investigations: calcium carbonate content, X-ray diffraction, scanning electron microscopy (SEM) images, optical and mechanical properties, in order to develop the best systems of retention additives for obtaining higher retention loads for making paper with high content of nano-filler material. The obtained results reveal that at the same level of calcium carbonate content, all paper samples with in-situ loading had higher the optical and mechanical properties than the paper obtained by conventional loading in all cases the additives studied. For all studied properties, nanoparticles had a positively influence over paper properties.

Elemental and macromolecular modifications in Triticum aestivum L. plantlets under different cultivation conditions.

Young wheat plantlets (wheatgrass), represent a significant source of minerals, enzymes, vitamins, while also rich in phenolics and chlorophylls, with considerable bioactivities. As the biosynthesis of such compounds may be influenced by growth conditions, the current research assesses wheatgrass composition in soil based and hydroponic systems, using water with different elemental composition. FTIR spectroscopy did not reveal significant variations between juice and extracts cultivated in different setups. Surface elemental composition indicated higher Na, P, Si concentrations in hydroponic plants, while AAS analyses showed increased Ca and Mn in soil presence. HPLC-MS of extracts showed that soil and spring water increased chlorophyll and hydroxychlorophyll a concentrations. Phenolic contents were higher in hydroponic plants, while maximum values were recorded for spring water. Radical scavenging activity was stimulated by the use of spring water. Results indicate that wheatgrass with improved mineral and macromolecular composition may be obtained using accessible cultivation setups.

Obtaining and Utilizing Cellulose Fibers with in-Situ Loading as an Additive for Printing Paper.

The goal of this study was to analyze the effects of cellulose fibers loading by precipitation in-situ of calcium carbonate over the properties of printing paper obtained from mixtures of the softwood and hardwood fibers. The effects of fibers with in-situ loading were analyzed comparatively with conventional paper loading respectively, by adding precipitated calcium carbonate into fiber stock. The effectiveness of the methods was evaluated by various analyses and investigations: calcium carbonate content, Scanning electron microscope (SEM) images, X-ray diffraction, optical and mechanical properties of the paper sheets. The evaluation of the effects on paper properties led to the conclusion that, at the same filler content, the in-situ loading method gives higher opacity and brightness than conventional methods. The utilization of cellulose fibers with in-situ loading as additive, shown as a modification of the ratio between fibers with in-situ loading and fibers without loading, regardless of whether they are softwood or hardwood fibers, allowed us to optimize printing paper properties, especially regarding the relationship between optical and strength properties.