Power and Specificity of FDR Under Smoothness

Poster submitted to OHBM 2005

Carrageenan as a dry strength additive for papermaking

<div><p>Carrageenans are commercially important sulfated gums found in various species of red seaweeds (Rhodophyta), wherein they serve a structural function similar to that of pectins in land plants. In this study, carrageenan was used independently or in combination with cationic polyacrylamide (CPAM) and/or Al₂(SO₄)₃ to explore its application as a dry strength additive in papermaking. Strength index determination, ash content detection, FTIR characterization and SEM observation were performed on prepared handsheets. The results showed that with 0.6% Al₂(SO₄)₃ and 0.2% carrageenan as additives, the tensile index increased by 13.53% and precipitated calcium carbonate (PCC) retention increased by 57.06%. With 0.6% Al₂(SO₄)₃, 0.2% carrageenan and 0.03% CPAM as additives, PCC retention increased by 121% while the tensile index did not fall compared to handsheets without additives, indicating that carrageenan could enhance the strength of handsheets and be used as an anionic dry strength agent.</p></div

FTIR spectra of Handsheets of grammage 70 g/m² with 20% PCC as filler.

<p>A) is spectrum of handsheet with no additive, B) is spectrum of handsheet with carrageenan dosage of 0.2%.</p

SEM images of handsheets without and with 0.2% carrageenan.

<p>SEM images of handsheets without and with 0.2% carrageenan.</p

Handsheets of grammage 70 g/m² with 20% PCC as filler, 0.2% & 0% carrageenan as additive at different Al₂(SO₄)₃ dosages were prepared.

<p>A) and B) are, respectively, tensile and bursting indices as a function of Al₂(SO₄)₃ dosage; C) is PCC retention as a function of Al₂(SO₄)₃ dosage.</p

Handsheets of grammage 70 g/m² with 20% PCC as filler at different additive dosages were prepared.

<p>A) and B) are, respectively, the tensile and bursting indices as a function of additive dosage; C) is PCC retention as a function of additive dosage.</p

The CV_I neurites are divided into five developmental phases.

<p>In P phase (<b>A</b>–<b>B</b>, <b>Q</b>), there are no synapses, microtubules, or synaptic vesicles in the neurite. In S phase (<b>C</b>–<b>D</b>, <b>R</b> and <b>T</b>), there are some microtubules, mitochondria, or a few small or big dark synaptic vesicles, but no synapse in the neurite. In T phase (<b>E</b>–<b>F</b>, <b>L</b> and <b>S</b>), the synapses have immature T-bar structures, a few synaptic vesicles gathered around the small T-Bar structure, and microtubules disappeared in the neurite. In B phase (<b>G</b>–<b>K</b>, <b>T</b>–<b>U</b>), the neurites look bifurcated or dendritic, the T-bar structure is incomplete, and the two different diameters of synaptic vesicles are still present. In M phase, (<b>M</b>–<b>O</b>, <b>V</b>) there are a lot of commensurate synaptic vesicles cluster around the typical T-bar structure, and few big dark synaptic vesicles; <b>P</b> shows the NMJ T-bar structure. All the neurites in P phase (<b>Q</b>), S phase (<b>R</b>, <b>T</b>), T phase (<b>S</b>), B phase (<b>T</b>–<b>U</b>) and M phase (<b>V</b>) can be observed simultaneously at L3w period, and there are no synaptic vesicles in the center of the big neurites (<b>Q</b>–<b>V</b>). In the same diagram, the large black box is enlarged from the small white box, and <b>N</b> is the magnification of the <b>M</b> diagram box. <b><i>P</i></b> indicates P phase, <b><i>S</i></b> indicates S phase, <b><i>T</i></b> indicates T phase, <b><i>B</i></b> indicates B phase and <b><i>M</i></b> indicates M phase. Triangle indicates synapse, thick arrow indicates the big dark synaptic vesicle and thin arrow indicates microtubule (B–D), and Mi indicates mitochondria. Scale Bar A–C: 100 nm; D–F, H–I, K–L, O–P: 200 nm; G, J, M: 500 nm.</p

The CV_II neurites are divided into five developmental phases.

<p>In P phase (<b>A</b>), there are not synapses, microtubules, or synaptic vesicles in the neurite. In S phase (<b>B</b>), there are some microtubules, mitochondria, or different sizes of synaptic vesicles, but no synapses. In T phase (<b>C</b>–<b>D</b>), there are residual microtubules and a greater variety in the size of synaptic vesicles in the neurite; the synapse is immature, and there is no T-bar structure formation. In B phase (<b>B</b>, <b>E</b>–<b>L</b>), the neurites look bifurcated or dendritic, and the two different diameters of synaptic vesicles remain present. In M phase, there are dark cytoplasm, typical T-bar structures and a lot of commensurate synaptic vesicles cluster around it, but the appearance of the neurite remain bifurcated or dendritic, and have several branches around it (<b>M</b>–<b>N</b>). In embryo stage, the synapses have not T-bar structures (<b>F</b>), but have the immature T-bar structures and dark cytoplasm throughout the larval stage (<b>G</b>–<b>L</b>) in B phase. In the same diagram, the large black box is enlarged from the small white box, and <b>H</b> is the magnification of the <b>G</b> diagram box. Triangle indicates synapse, thick arrow indicates the big dark synaptic vesicles, thin arrow indicates microtubules, asterisk indicates the axon and black long triangle indicates the nascent branch of neurite in B phase (<b>B</b>). <b><i>P</i></b> indicates P phase, <b><i>S</i></b> indicates S phase, <b><i>T</i></b> indicates T phase, <b><i>B</i></b> indicates B phase, <b><i>M</i></b> indicates M phase and Mi indicates mitochondria. Scale Bar A: 100 nm; B–H, K–M: 200 nm; I: 500 nm.</p

Label-Free SERS Monitoring of Chemical Reactions Catalyzed by Small Gold Nanoparticles Using 3D Plasmonic Superstructures

Label-free in situ surface-enhanced Raman scattering (SERS) monitoring of reactions catalyzed by small gold nanoparticles using rationally designed plasmonic superstructures is presented. Catalytic and SERS activities are integrated into a single bifunctional 3D superstructure comprising small gold satellites self-assembled onto a large shell-isolated gold core, which eliminates photocatalytic side reactions

Dynamic drainage tests were performed at a volume of 500 ml of 0.3 w% fibres and 0.13 w% PCC in water.

<p>Absorbance of filtrate and drainage speed are functions for Al₂(SO₄)₃ dosage.</p