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41.
NKS Gowda Dintaran T Pal Srinivas R Bellur Ujala Bharadwaj Manpal Sridhar Mayasandra L Satyanarayana Cadaba S Prasad Koodli S Ramachandra Koratikere T Sampath 《Journal of the science of food and agriculture》2009,89(2):216-220
BACKGROUND: Castor (Ricinus communis) seed cake (CSC), a byproduct of the vegetable‐oil industry, contains fairly good amounts of protein (crude protein, 290–390 g kg?1) which could be a suitable substitute of conventional oil cakes like soybean meal (SBM) in livestock diets but for the presence of a toxic glycoprotein, ricin. Efforts were, therefore, made to determine the feasibility of feeding CSC as such or after detoxification with lime (4%, wt/wt) by incorporating it into a total mixed ration (TMR) containing 65 and 35 parts ragi (Eleucine coracana) straw and concentrate mixture, respectively, with 11 g kg?1 CP and 50 g kg?1 TDN in which the SBM of a control diet was isonitrogenously replaced with either raw or lime‐treated CSC in test diets. The control and two test TMRs were fed to 24 sheep, respectively, divided at random into three dietary groups having equal number of animals for 150 days. RESULTS: Although lime treatment had a positive effect in reducing ricin by 58%, no adverse effect could be noticed by feeding raw or lime‐treated CSC in terms of body weight changes, macro‐ and micro‐nutrient utilisation, blood biochemical and mineral profile, rumen fermentation pattern, carcass traits, except the level of plasma immunoglobulins which was significantly (P < 0.05) higher in sheep fed CSC diets. No pathological lesions could be noticed in the tissues of visceral organs due to feeding the raw or treated CSC. CONCLUSIONS: The findings suggest no adverse effect in the nutritional performance of adult sheep due to feeding the raw or treated CSC when incorporated into TMRs, probably due to a dilution of the ricin concentration or the development of immunity to the glycoprotein ricin, warranting long‐term growth‐cum‐production studies. Copyright © 2008 Society of Chemical Industry 相似文献
42.
In the past decade, business process outsourcing (BPO) has emerged as an important economic and business issue. Successful offshoring and outsourcing of business processes to low-cost destinations has made BPO a strategic decision. Inconsistencies at the client and service provider levels globally are requiring clients to build competencies in outsourcing management. Clients are further pushing service providers to build capabilities such as business process management and information technology management competencies. A research survey is carried out with European clients to identify the critical competencies of the service provider and clients for building a successful relationship. The survey indicates that the clients’ focus is on BPO outcome delivery for building successful relationship and not so much on the service provider's competencies. 相似文献
43.
Due to the emergence of Grid computing over the Internet, there is presently a need for dynamic load balancing algorithms
which take into account the characteristics of Grid computing environments. In this paper, we consider a Grid architecture
where computers belong to dispersed administrative domains or groups which are connected with heterogeneous communication
bandwidths. We address the problem of determining which group an arriving job should be allocated to and how its load can
be distributed among computers in the group to optimize the performance. We propose algorithms which guarantee finding a load
distribution over computers in a group that leads to the minimum response time or computational cost. We then study the effect
of pricing on load distribution by considering a simple pricing function. We develop three fully distributed algorithms to
decide which group the load should be allocated to, taking into account the communication cost among groups. These algorithms
use different information exchange methods and a resource estimation technique to improve the accuracy of load balancing.
We conducted extensive simulations to evaluate the performance of the proposed algorithms and strategies. 相似文献
44.
45.
Particle growth by acid-catalyzed heterogeneous reactions of organic carbonyls on preexisting aerosols 总被引:1,自引:0,他引:1
Aerosol growth by the heterogeneous reactions of different aliphatic and alpha,beta-unsaturated carbonyls in the presence/absence of acidified seed aerosols was studied in a 2 m long flow reactor (2.5 cm i.d.) and a 0.5-m3 Teflon film bag under darkness. For the flow reactor experiments, 2,4-hexadienal, 5-methyl-3-hexen-2-one, 2-cyclohexenone, 3-methyl-2-cyclopentenone, 3-methyl-2-cyclohexenone, and octanal were studied. The carbonyls were selected based on their reactivity for acid-catalyzed reactions, their proton affinity, and their similarity to the ring-opening products from the atmospheric oxidation of aromatics. To facilitate acid-catalyzed heterogeneous hemiacetal/acetal formation, glycerol was injected along with inorganic seed aerosols into the flow reactor system. Carbonyl heterogeneous reactions were accelerated in the presence of acid catalysts (H2SO4), leading to higher aerosol yields than in their absence. Aldehydes were more reactive than ketones for acid-catalyzed reactions. The conjugated functionality also resulted in higher organic aerosol yieldsthan saturated aliphatic carbonyls because conjugation with the olefinic bond increases the basicity of the carbonyl leading to increased stability of the protonated carbonyl. Aerosol population was measured from a series of sampling ports along the length of the flow reactor using a scanning mobility particle sizer. Fourier transform infrared spectrometry of either an impacted liquid aerosol layer or direct reaction of carbonyls as a thin liquid layer on a zinc selenide FTIR disk was employed to demonstrate the direct transformation of chemical functional groups via the acid-catalyzed reactions. These results strongly indicate that atmospheric multifunctional organic carbonyls, which are created by atmospheric photooxidation reactions, can contribute significantly to secondary organic aerosol formation through acid-catalyzed heterogeneous reactions. Exploratory studies in 25- and 190-m3 outdoor chambers were also implemented to demonstrate the formation of high molecular weight organic structures. The reaction of ozone with alpha-pinene to generate secondary organic aerosols (SOAs) was performed in the presence of background aerosol consisting of a mixture of wood soot and diesel soot. Results strongly suggest that indigenous sulfuric acid associated with the combustion of fossil fuels (e.g., diesel soot) can initiate acid-catalyzed heterogeneous reactions of SOAs on the particle phase. 相似文献
46.
Testing of VLSI circuits is still a NP hard problem. Existing conventional methods are unable to achieve the required breakthrough in terms of complexity, time and cost. This paper deals with testing the VLSI circuits using natural computing methods. Two prototypical algorithms named as DATPG and QATPG are developed utilizing the properties of DNA computing and Quantum computing, respectively. The effectiveness of these algorithms in terms of result quality, CPU requirements, fault detection and number of iterations is experimentally compared with some of existing classical approaches like exhaustive search and Genetic algorithms, etc. The algorithms developed are so efficient that they require only N (where N is the total number of vectors) iterations to find the desired test vector whereas in classical computing, it takes N/2 iterations. The extendibility of new approach enables users to easily find out the test vector from VLSI circuits and can be adept for testing the VLSI chips. 相似文献
47.
利用聚合物前驱体陶瓷工艺制备了Si-Al-C-N陶瓷,并对陶瓷氧化和腐蚀特性进行了研究.结果表明掺入少量的Al将极大地提高Si-Al-C-N陶瓷的抗氧化和抗腐蚀能力.含1.4at%Al的Si-Al-C-N陶瓷的氧化速率较文献报道硅基材料的低10倍,并且在1200℃,50 h观察不到任何腐蚀.还讨论了Si-Al-C-N陶瓷的抗氧化与腐蚀的机理. 相似文献
48.
This paper presents a theoretical analysis of the performance of a flat plate solar collector with the heat removal fluid undergoing a phase change. The resultant efficiency expression is a modified Hottel-Whillier-Bliss equation. Numerical computations are made to investigate the effect of vaporisation and operational parameters on the collector's performance. The collector's efficiency increases with the increase in liquid length until a point is reached when the region of superheating the vapour disappears. The efficiency is higher when a heat removal fluid of high latent heat of vaporisation is used in the collector. An increase in the saturation temperature of the working fluid (with increase of pressure) in the collector reduces its efficiency. 相似文献
49.
Pt/graphite catalyst for hydrogen generation by HI decomposition reaction in S–I thermochemical cycle
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Hydrogen is an attractive energy carrier for future because of various reasons. Therefore its large scale production is the need of the hour. One of the ways to achieve this is sulfur iodine thermochemical cycle and HI decomposition reaction is one of the three reactions constituting the cycle. Pt/graphite catalysts with different loading of platinum were prepared by impregnating colloidal graphite with hexachloroplatinic acid solution followed by reduction under N2 flow. The catalysts prepared have been characterized by X‐ray diffraction, Raman, scanning electron microscopy, X‐ray photoelectron spectroscopy and Brunauer–Emmett–Teller surface area. These catalysts have been employed for liquid phase HI decomposition under different conditions. To evaluate the stability of this catalyst against noble metal leaching under the reaction conditions, the eluent was analyzed by using ICP‐OES. Platinum loaded catalysts (0.5%, 1% and 2%) show 8.4%, 17.5% and 23.4% conversion respectively. From the present study we conclude that Pt/graphite is a suitable and stable catalyst for liquid phase HI decomposition reaction. Copyright © 2015 John Wiley & Sons, Ltd. 相似文献
50.
Kalyani Patrikar Nakul Jain Dwaipayan Chakraborty Priya Johari Valipe Ramgopal Rao Dinesh Kabra 《Advanced functional materials》2019,29(8)
Charge transport properties of common donor copolymers in organic photovoltaics, poly({4,8‐bis[(2‐ethylhexyl)oxy]benzo[1,2‐b:4,5‐b′]dithiophene‐2,6‐diyl}{3‐fluoro‐2‐[(2‐ethylhexyl)carbonyl]thieno[3,4‐b]thiophenediyl}) (PTB7) and poly([2,6′‐4,8‐di(5‐ethylhexylthienyl)benzo[1,2‐b;3,3‐b]dithiophene]{3‐fluoro‐2[(2‐ethylhexyl) carbonyl]thieno[3,4‐b]thiophenediyl}) (PTB7‐Th), with molecular structures differing only in the pendant group, are studied. This is the first report of field‐effect transistor mobility (µFET) of PTB7‐Th (0.14 cm2 V?1 s?1) and the highest µFET for PTB7 (0.01 cm2 V?1 s?1). µFET of PTB7‐Th is found to be almost one order of magnitude higher than PTB7. To understand the influence of molecular structure on charge transport, hole reorganization energy (λh) is calculated from first‐principles. λh of PTB7‐Th (≈150 meV) is found to be lower than PTB7 (≈346 meV). Further, the ratio of hopping rate versus square of charge transfer integral calculated from Marcus theory using λh for these systems is found to indicate a higher rate of hole transfer across dimers or homojunction interface for PTB7‐Th. These results are supplemented by experimentally determined λ using bulk‐heterojunction organic solar cells, where λPTB7‐Th≈200 meV and λPTB7≈310 meV follow a similar trend. The effective hole‐mobility estimation from BHJ devices correlates well with these λ values. This study provides understanding of charge transport properties via reorganization energy, as a function of pendant group without altering the backbone of the chains. 相似文献