Gloyer-Taylor Laboratories (United States)

Hybrid cultivars and parboiled long grain brown rice are known to have greater milling yields than conventional pureline rice cultivars. The purpose of this study was to evaluate the hydration kinetics of parboiled brown rice cultivars as a factor impacting rice quality characteristics. Two pureline and four hybrid rice cultivars were used in this study. Parboiled and non-parboiled rice cultivars varied significantly (P < 0.05) in color, amylose, lipid content, cooked rice texture, and pasting properties with hybrids pronouncedly affected than pureline cultivars. The rate of moisture uptake in pureline cultivars was greater than in hybrids; a result attributed to the variation in moisture uptake kinetics as well as gelatinization temperature. Pureline cultivars had significantly (P < 0.05) lower pasting temperatures (i.e., 81.4 and 82.3 °C) compared to hybrid cultivars. Peleg and two-term exponential models had the highest correlation of determination (R2) and the lowest RMSE and P compared with other models used to study the hydration kinetics of rice cultivars. R2 values of actual and estimated moisture contents ranged from 0.968 to 0.876 to 0.999 and 0.995 for Peleg and two-term exponential models, respectively. RMSE of Peleg and two-term exponential models ranged from 0.095 to 1.637 and from 0.300 to 1.723, respectively.

ABSTRACTOrganosolv switchgrass lignin (SGL) and hardwood lignin (HWL) polymers are used as precursors to prepare low cost carbon fibers (CFs). Lignin powder and fiber samples are stabilized and carbonized at different conditions to investigate the effect of HCl on thermal‐oxidative stabilization time, mass yield, fiber diameter, and mechanical properties. The results show that HCl can accelerate stabilization and reduce the stabilization time from many hours to 75 min for the SGL fibers, and to 35 min for the HWL fiber. The rate of rapid stabilization in HCl/air is at least four times faster than conventional stabilization in air. The CFs prepared with two different stabilization methods have almost the same strength and modulus, but higher carbon yield is obtained with the rapid stabilization due to a short time of oxidation. Pores and defects observed on the surface and the cross‐section of the CFs across all stabilization conditions contribute to low fiber strength. © 2017 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2017, 134, 45507.

The effect of hydrocolloids (arabic gum, carrageenan, carboxymethyl cellulose, and xanthan gum) on the physical properties of acorn starch was investigated. First order mixture response surface model was used and the effects of 1% hydrocolloids on acorn starch water holding capacity, starch solution viscosity, gel strength, freeze–thaw stability, and pasting properties were evaluated. Contributions of each hydrocolloid on determining acorn starch functionality were also calculated. Hydrocolloid combinations significantly (p &lt; 0.05) decrease acorn starch water holding capacity held at 23.3°C from 213.6% of 100% starch to less than 208.3% with minor exceptions. The increase in holding temperature, however, increased water holding capacity (WHC) irrespective of the hydrocolloids set used. The flow behavior indices of treatments ranged from 0.43 to 0.99 and were significantly (p &lt; 0.05) greater than that of pure acorn starch (i.e., 0.66) for most treatments. The consistency coefficient of treatments were significantly (p &lt; 0.05) greater than that of the control and were best fit for the shear‐thickening model. Significant (p &lt; 0.05) improvement in gel strength and decrease in freeze–thaw stability of treatments compared to the control was also reported. The pasting properties of treatments increased with the use of hydrocolloids, thus showing the significant role of hydrocolloids in dictating the pasting characteristics of the acorn–hydrocolloids interaction.

Combustion instability is the largest technical risk in propulsion system development. Even with current CFD simulation capabilities, modeling an entire rocket system with unsteady CFD is not feasible. On the other hand, the complex interactions of mixing, combustion, vorticity, and more, make predictive analytical and reduced order models less-ideal as well. In this paper a methodology for using energy based methods to rigorously combine localized high fidelity unsteady CFD simulations with large scale system models is presented. This method identifies unsteady energy as a generalized energy based flame transfer function (EFTF) that captures all sources of unsteady energy production. The methods are discussed and a simple demonstration involving a partially premixed air/methane injector element driven at several amplitudes and frequencies is used to depict the process.

The effect of sequential acid, alkaline, and enzymatic treatment of chickpea and lentil flours on batter rheological properties was investigated. Substitution of wheat with disrupted chickpea and lentil flours significantly (P < 0.05) increased water-holding capacity from 66.8% in wheat flour to more than 70.0% based on the disruption treatment, indicating an improved adhesion of coated batter. Flow behavior index of batter treatments of partially replaced wheat flour with various ratios of disrupted chickpea and lentil flours ranged from 0.88 to 1.36 and was significantly (P < 0.05) lower than the flour (i.e., 2.15) and nondisrupted control (i.e., 1.28–1.38 for chickpea and 1.22–1.28 for lentil) flours. Consistency coefficients of disrupted chickpea and lentil flours were significantly (P < 0.05) greater when replacing wheat control, indicating a best fit for the shear-thickening model. Flour disruption decreased the treatment's pasting properties, except the setback, providing support for the significant role of proteins in dictating the pasting characteristics of batter flour treatments. Results of this study suggested a potential use for treated chickpea and lentil flours in enhancing batter rheological properties including adhesion and water-holding capacity.

Nonlinear unsteady energy transport theory predicts that when multiple coupled oscillatory acoustic modes are unstable, only one of these modes may dominate. This phenomenon produces unusual experimental results in propulsion systems as small changes may alter the stability of many modes, thereby altering their interactions as well. These nonlinear interactions create instances where unstable modes appear to switch, where, in fact, multiple modes are unstable. Understanding this phenomenon is critical in diagnosing combustion instability and in developing damping techniques in unstable systems. In order to verify this predicted phenomenon a forced Rijke tube experiment was performed. This experiment shows that the first mode instability caused by the Rijke tube is eliminated when higher modes are driven. This effect only occurs near the natural frequencies of the Rijke tube and is likely not the result of changes in the Rijke tube operation itself. The positive results of this experiment have applications in the development of new innovative combustion instability damping techniques in propulsion systems as well as validating the analytical methods applied. With this process, a fundamentally new way of damping is presented as it is possible to eliminate low frequency oscillations by either destabilizing higher frequency modes or by directly driving those higher modes.

Reconstruction after total sacrectomy is a critical component of malignant sacral tumor resection, permitting early mobilization and maintenance of spinal pelvic alignment. However, implant loosening, graft migration, and instrumentation breakage remain major problems. Traditional techniques have used interiliac femoral allograft, but more modern methods have used fibular or cage struts from the ilium to the L-5 endplate or sacral body replacement with transiliac bars anchored to cages to the L-5 endplate. This study compares the biomechanical stability under gait-simulating fatigue loading of the 3 current methods. Total sacrectomy was performed and reconstruction was completed using 3 different constructs in conjunction with posterior spinal screw rod instrumentation from L-3 to pelvis: interiliac femur strut allograft (FSA); L5-iliac cage struts (CSs); and S-1 body replacement expandable cage (EC). Intact lumbar specimens (L3-sacrum) were tested for flexion-extension range of motion (FE-ROM), axial rotation ROM (AX-ROM), and lateral bending ROM (LB-ROM). Each instrumented specimen was compared with its matched intact specimen to generate an ROM ratio. Fatigue testing in compression and flexion was performed using a custom-designed long fusion gait model. Compared with intact specimen, the FSA FE-ROM ratio was 1.22 ± 0.60, the CS FE-ROM ratio was significantly lower (0.37 ± 0.12, p < 0.001), and EC was lower still (0.29 ± 0.14, p < 0.001; values are expressed as the mean ± SD). The difference between CS and EC in FE-ROM ratio was not significant (p = 0.83). There were no differences in AX-ROM or LB-ROM ratios (p = 0.77 and 0.44, respectively). No failures were noted on fatigue testing of any EC construct (250,000 cycles). This was significantly improved compared with FSA (856 cycles, p < 0.001) and CS (794 cycles, p < 0.001). The CS and EC appear to be significantly more stable constructs compared with FSA with FE-ROM. The 3 constructs appear to be equal with AX-ROM and LB-ROM. Most importantly, EC appears to be significantly more resistant to fatigue compared with FSA and CS. Reconstruction of the load transfer mechanism to the pelvis via the L-5 endplate appears to be important in maintenance of alignment after total sacrectomy reconstruction.