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41.
Mahesh Gupta Nissreen Abu‐Ghannam Eimear Gallaghar 《Comprehensive Reviews in Food Science and Food Safety》2010,9(3):318-328
ABSTRACT: Barley is the basic raw material for brewing. Its chemical composition, brewing, and technological indices are highly determinative for the beer quality and the economical efficiency of the brewing process. Barley is rich in protein, carbohydrates, dietary fibers, minerals, and vitamins. The presence of nonstarch polysaccharides as mixed linkage (1‐3),(1‐4)‐β‐d ‐glucans and arabinoxylans together with the enzymes are responsible for barley modification. Malting is a complex process that involves many enzymes; important ones are α‐amylase, β‐amylase, α‐glucosidase, and limit dextrinase. During the process of malting and brewing, the by‐products left after separation of the wort are rich in protein, fibers, arabinoxylans, and β‐glucan. This review summarizes and integrates barley grain with respect to nutritional, functional, and compositional changes that take place during malting and brewing. It also explores in‐depth the several by‐products obtained after brewing and their potential for various food applications. Barley brewing by‐products offer an opportunity for cereal‐based baked and extruded products with acceptable sensory and nutritional characteristics. 相似文献
42.
Building useful systems with an ability to understand "real" natural language input has long been an elusive goal for Artificial Intelligence. Well-known problems such as ambiguity, indirectness, and incompleteness of natural language inputs have thwarted efforts to build natural language interfaces to intelligent systems. In this article, we report on our work on a model of understanding natural language design specifications of physical devices such as simple electrical circuits. Our system, called KA, solves the classical problems of ambiguity, incompleteness and indirectness by exploiting the knowledge and problem-solving processes in the situation of designing simple physical devices. In addition, KA acquires its knowledge structures (apart from a basic ontology of devices) from the results of its problem-solving processes. Thus, KA can be bootstrapped to understand design specifications and user feedback about new devices using the knowledge structures it acquired from similar devices designed previously.In this paper, we report on three investigations in the KA project. Our first investigation demonstrates that KA can resolve ambiguities in design specifications as well as infer unarticulated requirements using the ontology, the knowledge structures, and the problem-solving processes provided by its design situation. The second investigation shows that KA's problem-solving capabilities help ascertain the relevance of indirect design specifications, and identify unspecified relations between detailed requirements. The third investigation demonstrates the extensibility of KA's theory of natural language understanding by showing that KA can interpret user feedback as well as design requirements. Our results demonstrate that situating language understanding in problem solving, such as device design in KA, provides effective solutions to unresolved problems in natural language processing. 相似文献
43.
The present experimental study characterizes the turbulent LPG Inverse Diffusion Flame (IDF) stabilized in a backstep burner in terms of visible flame length, dual flame structure, centerline temperature distribution, and oxygen concentration. The visible flame length for a fixed fuel jet velocity is found to reduce with increase in air jet velocity. Besides this, the effect of air and fuel jet velocities on visible flame length is interpreted using a new parameter, Global Momentum Ratio (GMR). Interestingly, GMR seems to be correlating well with the visible flame length for the air and fuel velocity ranges considered in the present study. Moreover, the dual flame structure of IDF is identified with the help of CH-chemiluminescence signature. The existence of dual flame structure of IDF is confirmed further with the centerline temperature and oxygen concentration measurements. 相似文献
44.
That computing and communication systems are becoming increasingly interdependent is evident in almost every aspect of society. Applications of these integrated systems are also spreading. As this trend continues, it will force the computing community not only to develop revolutionary systems but also to redefine “computer system” and the roles of traditional research disciplines, such as operating systems, architectures, compilers, languages, and networking. Systems research faces an unprecedented challenge. Systems developers are facing a major discontinuity in the scale and nature of both applications and execution environments. Applications are changing from transforming data to directly interacting with humans; they will use hardware and data that span wide area, even global, networks of resources and involve interactions among users as well. Even the architecture of individual processors is uncertain. The authors look at three challenges facing systems research, describe developing solutions, and review remaining obstacles. Using this information, they formulate three clear first steps to addressing the identified challenges: (a) define a new paradigm for systems research; (b) attack problems common to all system development; (c) build a research infrastructure 相似文献
45.
46.
Chloromethylated styrene-divinylbenzene copolymer was chemically modified with ethylenediaminetetraacetic acid ligand. Catalytically
active polymer containing Ru(III) moieties were synthesized from this polymeric ligand. They were characterized using FTIR,
UV-vis, SEM, ESR and TGA. Other physico-chemical properties such as bulk density, surface area, moisture content and swelling
behaviour in different solvents were also studied. The polymer bound complex was used to study hydrogenation of 1-hexene ton-hexane under mild conditions. Influence of [1-hexene], [catalyst], temperature and nature of the solvent on the rate of the
reaction was investigated. A rate expression is proposed based on the observed initial rate data. Recycling efficiency of
the catalyst has also been studied. 相似文献
47.
48.
Polybenzimidazoles containing different contents of pendant nitrophenoxy groups were prepared by condensation of 3,3′‐diamino‐benzidine with a mixture of 3,5‐dicarboxyl‐4′‐nitro diphenyl ether and isophthalic acid (IPA) in different ratios in polyphosphoric acid. The polymers are soluble in polar aprotic solvents, they have inherent viscosities in the range of 0.75–1.10 dL g?1 and they form tough and transparent films on solution casting. They have good thermal stability with initial decomposition temperature ranging from 380 to 416°C in nitrogen, good tensile strength ranging from 56 to 65 MPa and reasonably good oxidative stability. Phosphoric acid uptake of these polymers is low compared with PBI and membranes doped with phosphoric acid exhibit good proton conductivity in the range of 6.6× 10?3 to 1.9× 10?2 S/cm at 25°C and 1.2× 10?2 to 4.9× 10?2 S/cm at 175°C, compared with 3.9× 10?3 S/cm at 25°C and 3.2× 10?2 S/cm at 175°C for PBI. These membranes are suitable for applications as polymer electrolyte for fuel cell and presumably for gas separation at high temperature. © 2010 Wiley Periodicals, Inc. J Appl Polym Sci, 2010 相似文献
49.
Mahesh N. Varma 《Fuel》2010,89(7):1641-31
Biodiesel was synthesized in supercritical fluids by two routes: non-catalytically in supercritical alcohols and by enzyme catalysis in supercritical carbon dioxide. Two oils, sesame oil and mustard oil, and two alcohols, methanol and ethanol, were used for the synthesis. Complete conversion was observed for synthesis in supercritical alcohols whereas only a maximum of 70% conversion was observed for the enzymatic synthesis in supercritical carbon dioxide. For the synthesis in supercritical alcohols, the activation energies and pseudo-first order rate constants were determined. For the reactions in supercritical carbon dioxide, a mechanism based on ping pong bi-bi was proposed and the kinetic parameters were determined. 相似文献
50.
Poly(lactic acid) (PLA) was synthesized using l ‐lactic acid by condensation polymerization. Polystyrene (PS) and surface modified montmorillonite (OMMT) was used for the preparation of PS:PLA composites and PS:PLA:OMMT nanocomposites. The composite materials prepared had varying amount of PLA (10–30%) and OMMT (0.5–5 phr). These composites were subjected to degradation in minimal medium using the fungi Aspergillus niger (A. niger) under controlled conditions. Scanning electron microscopy (SEM) showed the growth of microorganism on the polymer surface and fracture within the polymer matrix as a result of degradation. Fourier transform infra red spectroscopy (FTIR) was further used to determine the mechanism leading to biodegradation. It was found that the biodegradation of both PS:PLA and PS:PLA:OMMT took place mainly via break down and utilization of ester group, as can be seen from disappearance of absorption peak of ester group and simultaneous appearance of a typical IR absorption of microbial mass at 1450 cm−1. The thermal stability of PS:PLA:OMMT nanocomposites was found to increase with increasing concentration of OMMT, as observed from thermo gravimetric analysis (TGA), while mechanical property was found to be decreased after degradation at 30% of PLA and 5 wt% of OMMT content. Change in extracellular protein content, biomass production and % degradation with respect to time (up to 28 days) were studied and correlated to evaluate the effectiveness of A. niger in biodegradation of the composites. POLYM. COMPOS., 35:263–272, 2014. © 2013 Society of Plastics Engineers 相似文献