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The Processability Improvement of Duplex Stainless Steel
Shangtan Liu, Jann van Benthem
Open Access Library Journal (OALib Journal) , 2016, DOI: 10.4236/oalib.1102579
Abstract: This paper focuses on the duplex stainless steel processability and presents many practical technological approaches which are applied in many steel companies on how to improve the processability. First, take into consideration an appropriate hot working temperature; second, make sure cooling rate higher than 15℃/s; and third, conduct annealing treatment before delivery.
Gelation and Retrogradation Mechanism of Wheat Amylose  [PDF]
Yukihiro Tamaki,Teruko Konishi,Masakuni Tako
Materials , 2011, DOI: 10.3390/ma4101763
Abstract: The flow behavior, dynamic viscoelasticity, and optical rotation of aqueous solutions of wheat amylose were measured using a rheogoniometer and a polarimeter. The amylose solutions, at 25 °C, showed shear-thinning behavior at a concentration of 1.2%, but plastic behavior at 1.4 and 1.6%, the yield values of which were estimated to be 0.6 and 1.0 Pa, respectively. The viscosity of the wheat amylose increased a little with increase in temperature up to 10 or 20 °C at 1.2% or 1.4 and 1.6%, which was estimated to be a transition temperature. The elastic modulus increased with increase in concentration, and increased with increasing temperature up to 20, 25 and 30 °C, which was estimated to be a transition temperature, respectively, then decreased gradually but stayed at a large value even at high temperature (80 °C). A very low elastic modulus of the wheat amylose was observed upon addition of urea (4.0 M) and in alkaline solution (0.05 M NaOH) even at low temperature. The optical rotation of wheat amylose solution increased a little with decreasing temperature down to 25 °C, then increased rapidly with further decrease in the temperature. The mode of gelation mechanism of amylose molecules, which was previously proposed, was confirmed and a retrogradation mechanism of wheat amylose was proposed.
Processability of Pultrusion Using Natural Fiber and Thermoplastic Matrix  [PDF]
Tham Nguyen-Chung,Klaus Friedrich,Günter Mennig
Advances in Materials Science and Engineering , 2007, DOI: 10.1155/2007/37123
Abstract: Fundamental mechanisms of the pultrusion process using commingled yarns of polypropylene matrix and discontinuous flax fiber to produce thermoplastic profiles were investigated in numerical and experimental manners. Essential issue is the fact that all natural fibers are discontinuous by nature, which may negatively influence the processability. The pultrusion process will be only successful if the pulling force exerted on the solidified pultrudates can be transmitted to the regions of unmelted commingled yarns by “bridging over” those melted regions within the die. This can be realized by applying a sufficient number of small yarn bundles of high compactness rather than a thicker single bundle of lower compactness as the raw material. Furthermore, the possibility of adding extra melt into the yarn bundles by side-fed extrusion has been investigated showing that the impregnation can be improved only for the outer layers of yarns, which is owed to the high viscosity of the thermoplastic melt and the limited length of the die.
Somatic embryogenesis of selected coniferous tree species of the genera Picea, Abies and Larix
Krystyna Bojarczuk,Teresa Hazubska-Przyby?,Krystyna Szczygie?
Acta Societatis Botanicorum Poloniae , 2007, DOI: 10.5586/asbp.2007.001
Abstract: Experiments on somatic embryogenesis in selected spruce, fir and larch species were performed to determine if this method of micropropagation enables production of quality seedlings for forest nurseries. High frequencies of embryogenic callus in spruce (23-31%) and fir (29%) were achieved when mature zygotic embryos were used as explants, while in larches (36%) only when megagametophytes (endosperms with immature embryos) were used. The possibility of somatic embryogenesis initiation also from somatic embryos (resulting in secondary and third generation of embryogenic callus) indicate high efficiency of this method of micropropagation. The best results at all stages of somatic embryogenesis (good proliferation of embryogenic callus, high rate of embryo regeneration and their survival) were obtained for Norway spruce, European larch and some hybrid larches.
On the Conformational Properties of Amylose and Cellulose Oligomers in Solution  [PDF]
Moritz Winger,Markus Christen,Wilfred F. van Gunsteren
International Journal of Carbohydrate Chemistry , 2009, DOI: 10.1155/2009/307695
Abstract: Molecular dynamics (MD) simulations were used to monitor the stability and conformation of double-stranded and single-stranded amyloses and single-stranded cellulose oligomers containing 9 sugar moieties in solution as a function of solvent composition, ionic strength, temperature, and methylation state. This study along with other previous studies suggests that hydrogen bonds are crucial for guaranteeing the stability of the amylose double helix. Single-stranded amylose forms a helical structure as well, and cellulose stays highly elongated throughout the simulation time, a behavior that was also observed experimentally. In terms of coordination of solute hydroxyl groups with ions, amylose shows entropy-driven coordination of calcium and sulfate ions, whereas cellulose-ion coordination seems to be enthalpy-dominated. This indicates that entropy considerations cannot be neglected when explaining the structural differences between amyloses and celluloses.
RHEOLOGICAL CHARACTERIZATION OF PROCESSABILITY OF UNVULCANIZED POLYBUTADIENE
顺丁生胶加工行为的流变学表征

DU Xue,XU Yuan-ze,QIAN Ren-yuan,
杜雪
,许元泽,钱人元

高分子学报 , 1986,
Abstract: Rheological investigation on a series of unvulcanized polybutadiene elastomers of different processability has been carried out by means of a capillary extrusion rheometer. It is found that the processability of unvulcanized polybutadiene can be correlated with the occurrence of unsteady flow and the Wall stress dependence of the dimensionless number e characterizing the entrance elongational elasticity which has been found to be sensitive to the branching structure and the molecular weight distribution of the samples. Interpretations based on the structural data ofunvulcanized polybutadiene were discussed.
Development of high amylose wheat through TILLING
Ann J Slade, Cate McGuire, Dayna Loeffler, Jessica Mullenberg, Wayne Skinner, Gia Fazio, Aaron Holm, Kali M Brandt, Michael N Steine, John F Goodstal, Vic C Knauf
BMC Plant Biology , 2012, DOI: 10.1186/1471-2229-12-69
Abstract: Using TILLING to identify novel genetic variation in each of the A and B genomes in tetraploid durum wheat and the A, B and D genomes in hexaploid bread wheat, we have identified mutations in the form of single nucleotide polymorphisms (SNPs) in starch branching enzyme IIa genes (SBEIIa). Combining these new alleles of SBEIIa through breeding resulted in the development of high amylose durum and bread wheat varieties containing 47-55% amylose and having elevated resistant starch levels compared to wild-type wheat. High amylose lines also had reduced expression of SBEIIa RNA, changes in starch granule morphology and altered starch granule protein profiles as evaluated by mass spectrometry.We report the use of TILLING to develop new traits in crops with complex genomes without the use of transgenic modifications. Combined mutations in SBEIIa in durum and bread wheat varieties resulted in lines with significantly increased amylose and resistant starch contents.Wheat is a staple of the human diet and is incorporated into many food products including bread, cereals and pasta. The main component (60-70%) of the wheat grain is starch, the source of rapidly released glucose during digestion. With the rise in human health concerns such as obesity and diabetes, there has been an increasing interest in altering starch composition in cereal grains to raise the proportion of resistant starch. Resistant starch is defined as the fraction of starch that escapes digestion in the small intestine, and is considered a form of dietary fiber with beneficial health properties [1-3]. Because foods high in resistant starch are digested more slowly, they have been shown to improve the insulin response and increase satiety [4-10]. The benefits of resistant starch extend to colon health due to its fermentation in the large intestine [11,12].Starch contains two major glucose polymers, amylose and amylopectin, which differ in the degree of polymerization (DP) of glucan chains and in the frequenc
Survey of Starch Amylose Content in Naked Barley (H. vulgare. Nudum)  [PDF]
A. Mohammadkhani
Pakistan Journal of Nutrition , 2005,
Abstract: Starch of two lines of naked barley were extracted by three different methods of washing. The apparent amylose content were determined with the same standard method which recently has been modified for use with samples of 2-3 seeds of cereal. In the present experiment factorial design (2x3x3) was used. The starch extracted by soaking the seeds overnight in dilute ammonia solution grinding in NaCl solution in a microfuge tube with an appropriate pestle and decanting the starch slurry. Then it was washed in 4M NaCl, SDS and acetone. The results of apparent amylose content of this method statistically were better than the two others. With present selected method the apparent amylose content ranged from 18 to 34% was determined for 145 accessions of naked barley. The lowest amylose content was related to the line of 4062 from Pakistan and the highest one was related to the line of 743 from Turkmenstan. This range is considered sufficiently broad to allow amylose content to be further diversified through the working with more lines and breeding.
Strength of Fractured Rocks  [PDF]
Chandreyee Roy,Srutarshi Pradhan,Anna Stroisz,Erling Fjaer
Physics , 2015,
Abstract: In this report we present a study on the strength of rocks which are partially fractured from before. We have considered a two dimensional case of a rock in the form of a lattice structure. The fiber bundle model is used for modelling the $2-D$ rock. Each lattice site is considered to be a fiber which has a breaking threshold. Fractures in this system will be of the form a cluster of sites and the length is defined as the number of sites belonging to a single cluster. We introduce fractures in the system initially and apply load until the rock breaks. The breaking of a rock is characterized by a horizontal fracture which connects the left side of the lattice to the right side. The length distribution and the strength of such systems have been measured.
AMYLOSE/AMYLOPECTIN SIMPLE DETERMINATION IN ACID HYDROLYZED TAPIOCA STARCH
WUTTISELA,KARNTARAT; SHOBSNGOB,SUJIN; TRIAMPO,WANNAPONG; TRIAMPO,DARAPOND;
Journal of the Chilean Chemical Society , 2008, DOI: 10.4067/S0717-97072008000300002
Abstract: analysis of the shift of wavelength máximum using a rapid colorimetric method was used to determine the ratio of amylose:amylopectin (am:ap) in acid-hydrolyzed tapioca starch. the absorbance máximum of 600 nm (am:ap of tapioca starch ≈ 22:78) moved to shorter wavelengths (590, 585, 570, 560, and 534 nm) as the decrease of the am:ap ratio due to hydrolysis of shorter chains that are not be able to form a complex with iodine. the amount of amylopectin itself may be unaltered or slightly decreased but the decrease in amylose caused a decrease in am:ap ratio
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