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21.
22.
Cladosporium herbarum grown as a surface culture in a chemically defined medium of sucrose and inorganic salts gave a high yield of fat (29.2%). The component acids of this fat have been found to be palmitic (34.2%); oleic (15.9%); linoleic (34.2%) and linolenic (15.7%). The combined proportion of linoleic and linolenic acids being about 50 per cent, the fat will be of great value for the manufacture of oil-modified resins as the films produced by such resins do not become yellow with age.  相似文献   
23.
The Journal of Supercomputing - Cluster-based routing protocols have been proven efficient in prolonging the life cycle of wireless sensor networks (WSNs). Periodic and multi-hop clustering are the...  相似文献   
24.
Neural Computing and Applications - Grouping the sensor nodes into clusters is an effective way to organize wireless sensor networks and to prolong the networks’ lifetime. This paper presents...  相似文献   
25.
Ionic flow associated with neural activation of the brain produces a magnetic field, called the neuromagnetic field, that can be measured outside the head using a highly sensitive superconducting quantum interference device (SQUID)-based neuromagnetometer. Under certain conditions, the sources producing the neuromagnetic field can be localized from a sampling of the neuromagnetic field. Neuromagnetic measurements alone, however, do not contain sufficient information to visualize brain structure. Thus, it is necessary to combine neuromagnetic localization with an anatomical imaging technique such as magnetic resonance imaging (MRI) to visualize both function and anatomy in vivo. Using experimentally measured human neuromagnetic fields and magnetic resonance images, the authors have developed a technique to register accurately these two modalities and have applied the registration procedure to portray the spatiotemporal distribution of neural activity evoked by auditory stimulation.  相似文献   
26.
The nonlinear Boussinesq equation is used to understand water table fluctuations in various ditch drainage problems. An approximate solution of this equation with a random initial condition and deterministic boundary conditions, recharge rate and aquifer parameters has been developed to predict a transient water table in a ditch-drainage system. The effects of uncertainty in the initial condition on the water table are illustrated with the help of a synthetic example. These results would find applications in ditch-drainage design.Notation A / tanh t - a lower value of the random variable representing the initial water table height at the mid point - a+b Upper value of the random variable representing the initial water table height at the midpoint - B tanh t - C 4/ - h variable water table height - h mean of the variable water table height - h m variable water table height at the mid point - h m mean of the variable water table height at the mid point - K hydraulic conductivity - L half spacing between the ditches - m 0 initial water table height at the mid point - N Uniform rate of recharge - S specific yield - t time of observation - x distance measured from the ditch boundary - (4/SL)(NK)1/2 - (L/4)(N/K)1/2 - dummy integral variable  相似文献   
27.
Thus it may be summarised that work hardening behaviour of the alloy superni 263 can not be analysed using the simple power law equation. The work hardening behaviour is satisfactorily analysed using the modified power law equation (Ludwigson equation). There is systematic variation in the different work hardening parameters K1, n1, K2, n2 and C with the period of ageing at 800 °C. The drastic lowering of the parameters n1 and eup, from ageing even for a short duration, suggests that this material should be formed in fully solution treated condition and any precipitation of γ′ must be avoided for good formability.  相似文献   
28.
Metallurgical and Materials Transactions A - The design of high entropy alloys (HEAs) can be accelerated using machine learning (ML) algorithms. In the current study, the design parameter’s...  相似文献   
29.
R. P. Singh 《Polymer Bulletin》1981,6(3-4):175-181
An investigation of the photo-oxidative degradation and stabilization of IIR and SBR in the temperature range of 258 to 313°K in air with a monochromatic light of 366 nm in the absence and presence of various concentrations of the different copper chelates has been described. The stabilizer performance in IIR and SBR was accessed by carbonyl index and quantum yield measurements. The changes of IIR and SBR during the irradiation with an ultra-violet light (366 nm) have been conducted by viscometrically and actinometric techniques. Irradiations were conducted on the films at 0, 2, 4, 6, 8, 10, 12 and 14 hours and various parameters were obtained.  相似文献   
30.
Thermal behaviour of starch-graft-polyacrylamide (S-g-PAM) copolymers was evaluated. Grafting of polyacrylamide onto starch lowers the initial decomposition temperature. However, the over-all stability as assessed by the shape of thermogravimetric curve and integral procedural decomposition temperature increased with an increase in % graft-on.  相似文献   
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