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81.
Patrick N Okoh Roman P Kubiczek Placid C Njoku Grace T Iyeghe 《Journal of the science of food and agriculture》1989,49(3):271-279
Grains of two sorghum (Sorghum vulgare L) varieties were germinated at room temperature for 2, 4 and 6 days. Germination resulted in an increase in protein content due to dry matter loss; this rose with increasing time of germination. The absolute amount of tannin was unchanged until the fourth day of germination but decreased markedly by the sixth day. Fractionation of the grain protein of one variety showed that there was a large increase in the albumin-globulin fraction (rich in lysine) and a decrease in the kafirin and cross-linked kafirin fraction (low in lysine) as a result of germination. Although these changes resulted in a more than 30% increase in lysine content on the fourth and sixth days of germination, a substantial loss in dry matter occurred when germination was continued up to 6 days. When 14-day-old Hubbard chicks were fed a diet containing about 59% malted sorghum supplemented with lysine, they showed better (P < 0.05) weight gain and efficiency of feed conversion than those on malted sorghum without lysine supplementation. However, malting reduced the amount of lysine needed to supplement the diet from 0.25% for unmalted sorghum to 0.18% for malted sorghum. 相似文献
82.
83.
Roman Klimkiewicz Helena Teterycz Hanna Grabowska Ireneusz Morawski Ludwik Syper Benedykt W. Licznerski 《Journal of the American Oil Chemists' Society》2001,78(5):533-535
A mixture of methyl esters of fatty acids obtained by transterification of nonerucic rape oil was ketonized. The starting
material, diluted with methanol, was converted at atmospheric pressure over a catalyst that contained Sn, Ce, and Rh oxides
in a molar ratio of 90:9:1. At a temperature of 385°C ketones were obtained with a total yield of 63% at the 96% conversion
of starting material. The reported experiments prove that catalysts other than iron that are active in ketonization of primary
alcohols can be successfully used in ketonization of esters of fatty acids. The kind of diluent used plays a crucial role
in the conversion. 相似文献
84.
Jianliang Lin William D. Sproul John J. Moore Roman Chistyakov Bassam Abraham 《Surface & coatings technology》2011,206(7):1780
The paper presents the results on the deposition of nanoscale structurally laminated CrN films using a novel multi pulse modulated pulsed power (MPP) magnetron sputtering technique. With the multi pulse MPP approach, thin films with a structural modulation in the nanometer range are obtained by alternately switching two (or even more) high power MPP pulses on the same target, which have different pulse lengths, frequencies and powers. Each pulse was turned on for a pulse repeat duration during which this given pulse shape was repeated. In this study, CrN films have been deposited in a closed field unbalanced magnetron sputtering system using the multi pulse MPP technique by varying the pulse repeat duration of two different pulses. The CrN films were also deposited by dc magnetron sputtering (dcMS) and single pulse MPP techniques for comparison. The microstructure and properties of the films were characterized using glancing incident X-ray diffraction, scanning electron microscopy, transmission electron microscopy, nanoindentation, and ball-on-disk wear tests. The structure and properties of the multi pulse MPP CrN films depended on the pulse repeat duration. The highest hardness of 30.5 GPa and an H/E ratio of 0.9 have been achieved in the multi pulse MPP CrN films. The wear rate of the single pulse MPP and multi pulse MPP CrN films decreased by a factor of 5.8–17 as compared to the dcMS CrN films. 相似文献
85.
Roman Cichon Krystyna Elkowicz Halina Kozlowska Antoni Rutkowski Willem C. Sauer 《Journal of the science of food and agriculture》1980,31(7):677-684
The nutritive value of protein of blends consisting of meat and soya bean protein products, which replaced either 20 or 40 % of protein of meat, were determined in rat feeding experiments. Protein efficiency ratio (PER) and net protein utilisation (NPU) were significantly lower (P<0.05) in blends containing either 20% protein from soya isolate or 40% protein from soya concentrate or soya flakes than blends containing sirloin only. However, there were no significant differences in PER and NPU when model meat (consisting of 70 and 30% protein from sirloin and connective tissue, respectively) was replaced by up to 20% protein from soya isolate or up to 40% protein from soya concentrate. 相似文献
86.
87.
Roman Werner Bernadette Bollwein Roman Petersen Johannes Tippmann Thomas Becker 《化学工程与技术》2017,40(3):450-458
The cleaning of filter cloths is necessary to avoid prolonged system downtime and strong fouling. Reliable cleaning concepts are central to the removal of residues from the complex surface of filter cloths. Particle residues, in particular, play a decisive role in the sufficiency of the cleaning performance. Consequently, enhanced particle‐removal cleaning concepts based on pulsatile jets for filter cloths have been developed. By varying the cleaning parameters, it has been demonstrated that increased pulse numbers and velocities improve the cleaning performance. Furthermore, this promising cleaning concept cleaned more effectively than conventional methods. The reduction in the amount of detergent needed is an ecological and economic advantage of pulsatile cleaning. 相似文献
88.
Refractory Y-α-SiAlON with elongated grain morphology was obtained by utilizing La2 O3 as a densification aid, which resulted in excellent room-temperature and high-temperature strength. Room-temperature strength of 1000 MPa was achieved when La2 O3 was augmented by adding Y2 O3 or removing AlN. With only La2 O3 , a temperature-independent strength of 800–950 MPa was maintained up to 1100°C, then gradually decreasing by 25% when reaching 1300°C. The R-curve measurements of fracture toughness showed relatively little dependence on microstructure, consistent with a strong interface that suppresses grain boundary decohesion. Compared with other densification aids such as SiO2 , Al2 O3 , Sc2 O3 , Y2 O3 , and Lu2 O3 , a finer microstructure was obtained by using La2 O3 . High nitrogen content in the residual La–Si–Al–O–N glass in equilibrium with the nitrogen-rich α-SiAlON is suggested to be the cause of these findings. 相似文献
89.
Roman A. Perez Maria-Pau Ginebra 《Journal of materials science. Materials in medicine》2013,24(2):381-393
A bone inspired material was obtained by incorporating collagen in the liquid phase of an α-tricalcium phosphate cement, either in solubilized or in fibrilized form. This material was able to set in situ, giving rise to a calcium deficient hydroxyapatite (CDHA)/collagen composite. The morphology and distribution of collagen in the composite was shown to be strongly affected by the collagen pre-treatment. The interactions between collagen and the inorganic phase were assessed by FTIR. A red shift of the amide I band was indicative of calcium chelation by the collagen carbonyl groups. The rate of CDHA formation was not affected when diluted collagen solutions (1 mg/ml) were used, whereas injectability improved. The presence of solubilized collagen, even in low amount (1 %), increased cell adhesion and proliferation on the composites. Still in the absence of osteogenic medium, significant ALP activity was detected both in the inorganic and the collagen-containing cements. The maximum ALP activity was advanced in the collagen-containing cement as compared to the inorganic cement. 相似文献
90.
Dipl.-Ing. Dr. mont. Pawel Krajewski Christian Bernhard Roman Krobath Thomas Schaden Sergiu Ilie 《BHM Berg- und Hüttenm?nnische Monatshefte》2014,159(7):304-305
Continuous casting of steel free of surface cracks is still one of the major quality challenges in the whole steel production. The key roles for the phenomenon of surface cracking are played by the critical strain and the temperature-dependent material’s phenomena. The new In-Situ Characterization Bending (IMC-B) method will enable the investigation of the critical strains with respect to the cracking under the main continuous casting boundaries. This publication presents potential and interesting results of the IMC-B experiment. 相似文献