5properties of paper and paperboard

... effect of desipramine and fluoxetine was tested in a murine model of septic shock, in which endo- toxemia and systemic inflammation is triggered by LPS injection. Production of TNF-α is one of the ... pred- nisolone and fluoxetine reduced the number of macrophages (by 60% and 51%, respectively), lym- phocytes (by 70% and 33%, respectively), neutrophils (by 72% and 38%, respectively) and eosinophils ... in the model of septic shock. Concentrations of 1 to 10 μM were required to down-regulate AP-1 and NF-κB activ- ities and expression of inflammatory cytokines. Such con- centrations of antidepressants

Ngày tải lên: 12/08/2014, 15:20

... recognized as standardized tests. Some of these tests, however, have been standardized and are described in the publications of the American Society for Testing and Materials (1). Many of the important ... Tests and Polymer Transitions 3 II. MECHANICAL TESTS There are a bewildering number of mechanical tests and testing instru- m ents. Most of these tests are very specialized and have not been officially ... that a standardized test may be no better than one that is not considered a standard. One objective of a standardized test is to bring about simplicity and uniformity to testing, and such

Ngày tải lên: 13/08/2014, 16:21

... between 1.0 and 1.2; it is a function of the ratio of segmental mobilities of cross- linked to uncross-linked polymer units and the relative cohesive energy densities of cross-linked and uncross-linked ... 60).because of this, each group can be assigned an apparent Tg value, and th e Tg value of a polymer becomes Che sum of the contri- Mechanical Tests and Polymer Transitions 19 tuitions of all ... moderate rates of deformation, the amorphous polymer is soft and flexible and is either an elastomer or a very viscous l iq uid, Mechanical properties show profound changes in the region of the glass

Ngày tải lên: 13/08/2014, 16:21

... weight and molecular weight distribution, degree of cross-linking, and of Plasticization. For two-phase and multiphase systems such as semi- crystalline polymers and polymer blends, morphology and ... made and there is no equivalent to the characteristic time of Figure 5A). In this section we summarize the effect of structural and compositional factors on the modulus of the simplest of amorphous ... the lowest value of £ 0 and T y shown and poly(methyl methacrylate) has the highest, there is no consistent correla- tion of 4o A , and /].,. Plazek has questioned the variation of ^ with t K

Ngày tải lên: 13/08/2014, 16:21

... effect of any change in £ ()jr Copolymers and plasticized materials often show another effect—a broadening of the transition region with a decrease in the slope of the modulus curve in the region of ... plateau. Plasticizers and Copolymerization also shift the glass transition responses of the amorphous phase of crystalline polymers. In addition, the degree of Crystallinity and melting point are ... mechanical properties of compatible blends resemble those of random copolymers, having a single T^ value and modulus tran- sition zone. T K varies rather regularly with composition, often following

Ngày tải lên: 13/08/2014, 16:21

... Creep and Stress Relaxation I. INTRODUCTION Creep and stress-relaxation tests measure the dimensional stability of a material, and because the tests can be of long duration, such tests are of great ... used. When the stresses and strains become large and the stress-strain curve becomes nonlinear, simple descriptions of the response and interconversions between creep and relaxation become increasingly ... unit, which consists of a Hookean spring and a Newtonian dashpot in series as shown in the insert in Figure 1. The modulus or stiffness of the spring is E, and the viscosity of the dashpot is r\.

Ngày tải lên: 13/08/2014, 16:21

... ratio of a viscosity to a modulus, as in the spring-dashpot model of Figure 1, but each sprint! has the same (shear) modulus, and the steady-flow viscosity T] of equation (16) is the sum of the ... (Williams, Landel, and Ferry) equation, which describes the effect of tem- perature on the time scale of the response. The Boltzmann superposition principle states that the response of a material ... of pounds per square inch and is in seconds. Doubling the load after 400 s gives a total creep that is the superposition of the original creep curve shifted by 400 s on top of the extension of

Ngày tải lên: 13/08/2014, 16:21

... llavsky and Prins (60) and co-workers have presented similar explicit results for a series of polyurethanc rubbers. Thus the response can be separated or factored into functions of time and of stress. ... dependence of crazing on molecular weight of polystyrene in the presence of certain liquids is well illustrated by the data of Rudd (130). As a result of crazing by butanol, he found that the rate of ... discussions of since describes the shape of the stress-strain curve and we are dealing here with creep and stress relaxation. Factorizability has also been found to apply to polymer solutions and melts

Ngày tải lên: 13/08/2014, 16:21

... polymer, and is the volume fraction of polymer. Creep and Stress Relaxation 101 3. Mixing a high-viscosity liquid with one of low viscosity reduces the viscosity just because of the dilution of the ... modulus is simply the sum of the time-depenent contributions of the Rouse-like segment motion of the cross-linked polymer chains [equations (17) and (16) or (46)] and of the equilibrium modulus ... state and the steady-state compliance, but the star polymers also decrease the rate of stress relaxation (and creep) compared to a linear polymer (169). The decrease in creep and relaxation rate of

Ngày tải lên: 13/08/2014, 16:21

... polybutadiene (195) and plasticized methacrylate (196). Farlie (197) has measured both the rate of creep and the rate of stress relaxation of natural rubber as a function of the degree of cross-linking. ... degree of cross-linking is given in terms of the swelling ratio q, which is defined as the ratio of the volume of the swollen gel to the volume of the unswollen gel. A crude estimate of the perfection ... treatment of the effect of chemical cross- links in reducing the number of entanglements would remove the slight hump seen in the calculated curves of Figures 18 and 19. The chemical nature of the

Ngày tải lên: 13/08/2014, 16:21

... amount of Creep and Stress Relaxation 115 Crystallinity—about.i to 15% (213,232). The creep of plasticized poly(vinyl chloride) polymers as a function of temperature, concentration, and kind of plasticizer ... the value of the two polymers, the blockiness of the chain, the compatibility of the two components, and the morphology of the resulting two-phase system. Thus for di- or triblocks of the AB ... (234), and Sabia and Eirich (243). These last workers also studied stress relaxation (244). In the case of crystalline polymers, plasticizers and Copolymerization reduce the melting point and the

Ngày tải lên: 13/08/2014, 16:21

... Electronic and magnetic properties of alkali and alkaline earth metals doped AlN: bulk to surfaces SANDHYA CHINTALAPATI (M.Sc; University of Hyderabad) A THESIS SUBMITTED FOR THE DEGREE OF DOCTOR OF ... surfaces SANDHYA CHINTALAPATI NATIONAL UNIVERSITY OF SINGAPORE 2015 [...]... (c) and PDOS of Be and N atoms (d) of 10) Be doped (11¯ surface 107 20) 7.3 Total DOS of (10¯ (a), ... DOS of (11¯ (b), and total DOS of p10) 20) (000¯ (c) surfaces of K doped AlN, and their corresponding spin den1) sity plots are shown at the right side 110 7.4 PDOS of K and

Ngày tải lên: 09/09/2015, 08:12

... following chapter different paper grades and their requirements are discussed Table 1: Properties of filler pigments (VTT, 2009) 14 (36) Paper and paperboard grades Paper and paperboard grades can ... basis weights of offset papers range from 40 to 300 g/m2 The majority of offset papers are produced in sheets (Paulapuro, 2000) Lightweight papers Offset papers and lightweight papers differ ... magnitude of printing and writing paper production The production shares have remained similar with only minor changes during the last years 4.2 Paper and paperboard demand Paper demand and consumption...

Ngày tải lên: 18/03/2014, 02:20

... point to point and is a combination of uniaxial and biaxial orientation A second type of anisotropic system is the biaxially oriented or planar random anisotropic system This type of material is ... is applied, and Lo the unstretched length of the specimen Equation (6) also applies to and gives one of the moduli of anisotropic materials if the applied stress is parallel to one of the principal ... deflection V is measured and the Young's modulus E is calculated as follows: where C and D are the width and thickness of the specimen (11,12) This flexure test often gives values of the Young's modulus...

Ngày tải lên: 13/08/2014, 16:21

... mRNA and also of its own transcript For this reason, the level of mRNA for the wildtype form of MCPIP and the level of mRNA for IL-1b (Fig 5A, lane 3) were lower in comparison to the level of mRNA ... lanes 2,3 and 4, lower band) The levels of mutant and wild-type MCPIP mRNAs were higher when these vectors were co-transfected with a vector overexpressing IL-1b (Fig 5, lanes and 4, upper bands) ... clarify the dynamics and features of this protein Role of MCPIP in regulation of the endogenous IL-1b transcript level After identification of a PIN domain in the MCPIP by use of bioinformatics,...

Ngày tải lên: 18/02/2014, 14:20

... characteristics and mechanical properties of bamboo Dissertation, Chinese Academy of Forestry, Beijing, China pp 147 Yusoff, M.N.M, A Abd.Kadir, and A.H Mohamed 1992 Utilization of bamboo for pulp and paper ... longitudinal and radial directions of one, three, and five year old bamboo and determine the correlation between SG and bending properties, and (5) compressive strength of bamboo at different ages and ... layer of bamboo in order to have a better understanding of the effect of these factors on the chemical composition of bamboo It can also provide chemical composition data for the pulp and paper...

Ngày tải lên: 22/02/2014, 09:20

... mitochondrial isoform (referred to henceforth as MiTK) as described below The cDNA for the cytoplasmic TK consists of 1811 bp with an ORF of 1098 bp and 5¢ and 3¢ untranslated regions of 21 and 692 bp, ... other hand, mitochondrial TK showed activity for taurocyamine, lombricine (30% of that of taurocyamine) and glycocyamine (7% of that of taurocyamine) Recombinant Arenicola MiTK was incapable of phosphorylating ... Alignment of mitochondrial targeting sequences of vertebrate and invertebrate MiCKs and Arenicola MiTK Sequences correspond to ubiquitous (uMiCK) and sarcomeric (sMiCK) MiCKs from man and chicken and...

Ngày tải lên: 07/03/2014, 21:20

... lg of platelet protein and 0.5 lg of GST and GST±Rab proteins; (B) an [a-32P]GTP overlay [17] of a nitrocellulose blot of a gel containing 40 lg of platelet protein, 0.5 lg of GST and 0.5 lg of ... form of Rab32 (see Discussion) Fig Puri®cation and properties of wild-type and mutant Rab31 and Rab32 expressed as GST±fusion proteins Samples of platelet particulate fraction protein and of puri®ed ... immunoblot of a gel containing 20 lg of platelet protein and 0.1 lg of GST and GST±Rab proteins, using a : 1000 dilution of anti-Rab31 antiserum; (D) a similar immunoblot using a : 1000 dilution of anti-Rab32...

Ngày tải lên: 08/03/2014, 16:20

... the field of papermaking unique /67/ 37 INTERNAL SIZING OF PAPER AND BOARD The word sizing is used when talking about paper and board hydrophobation Two kinds of sizing; internal sizing and surface ... dominating type of penetration is determined by the properties of the liquid phase, structure of the paper and board, pressure, temperature, penetration time and the hydrophobicity of the paper and board ... /82/: 43 The size of the particles to be retained The size of pores in the web and geometry of forming fabric (wire) The forming rate of paper or board web Basis weight of paper or board The...

Ngày tải lên: 09/03/2014, 01:20

... both in shape and in dimension to the fibrils of hTTR and sbTTR formed by heating The thick and straight morphology of heat-induced fibrils of hTTR, sbTTR and ecTRP is similar to that of amyloid fibrils ... Stability and fibril formation of TTR and TRP Fig DSC profiles of hTTR, sbTTR, and ecTRP The melting temperatures (Tm) were 97.8 °C for hTTR, 93.0 °C for sbTTR, and 66.7 °C for ecTRP Fig Analysis of tetramer ... Stability and fibril formation of TTR and TRP E Lundberg et al diversity in age of onset, penetrance, and tissues affected [7,8] SSA is a geriatric disease affecting approximately 25% of the European...

Ngày tải lên: 16/03/2014, 01:20