Scattering of the radiation with continuous spectrum on irregularities of a plane plasma layer

Author(s):  
G.V. Jandieri ◽  
Z.M. Diasamidze ◽  
M.R. Diasamidze ◽  
V.G. Jandieri
1973 ◽  
Vol 9 (1) ◽  
pp. 33-47 ◽  
Author(s):  
V. V. Demchenko† ◽  
K. E. Zayed

We investigate electrostatic surface-wave damping in strongly inhomogeneous magneto-active plasma with collisions. We demonstrate that such damping occurs at wave frequencies close to the natural (hybrid) frequencies of the plasma oscillations. We obtain dispersion equations and expressions for the damping coefficients of surface waves propagating along (i) the interface of semi-infinite plasmas, (ii) a plane plasma layer, and (iii) a vacuum layer in the plasma. We also study the linear transformation of surface waves into longitudinal oscillations (concentrated in the transition layer and directed along the gradient of plasma density) caused by the initial perturbation.


2017 ◽  
Vol 76 (14) ◽  
pp. 1273-1286
Author(s):  
Yu. V. Kirichenko ◽  
V. D. Karlov ◽  
А. S. Kiyko

1967 ◽  
Vol 28 ◽  
pp. 177-206
Author(s):  
J. B. Oke ◽  
C. A. Whitney

Pecker:The topic to be considered today is the continuous spectrum of certain stars, whose variability we attribute to a pulsation of some part of their structure. Obviously, this continuous spectrum provides a test of the pulsation theory to the extent that the continuum is completely and accurately observed and that we can analyse it to infer the structure of the star producing it. The continuum is one of the two possible spectral observations; the other is the line spectrum. It is obvious that from studies of the continuum alone, we obtain no direct information on the velocity fields in the star. We obtain information only on the thermodynamic structure of the photospheric layers of these stars–the photospheric layers being defined as those from which the observed continuum directly arises. So the problems arising in a study of the continuum are of two general kinds: completeness of observation, and adequacy of diagnostic interpretation. I will make a few comments on these, then turn the meeting over to Oke and Whitney.


2020 ◽  
Vol 2 (3) ◽  
Author(s):  
Jeffrey B. Parker ◽  
J. W. Burby ◽  
J. B. Marston ◽  
Steven M. Tobias

1998 ◽  
Vol 544 ◽  
Author(s):  
Hans J Griesser ◽  
Keith M McLean ◽  
Gerrit J Beumer ◽  
Xiaoyi Gong ◽  
Peter Kingshot ◽  
...  

AbstractCoatings of biologically active molecules on synthetic ”bulk“materials are of much interest for biomedical applications since they can in principle elicit specific, predictable. controlled responses of the host environment to an implanted device. However, issues such as shelf life. storage conditions, biological safety, and enzymatic attack in the biological environment must be considered; synthetic proteins may offer advantages. In this study we investigated the covalent immobilization onto polymeric materials of synthetic proteins which possess some properties that mimic those of the natural protein collagen, particularly the ability to form triple helical structures, and thus may provide similar bio-responses while avoiding enzymatic degradation. In order to perform immobilization of these collagen-like molecules (CLMs) under mild reaction conditions, the bulk materials are first equipped with suitable surface groups using rf plasma methods. Plasma polymer interlayers offer advantages as versatile reactive platforms for the immobilization of proteins and other biologically active molecules. Application of a thin plasma polymer coating from an aldehyde monomer is particularly suitable as it enables direct immobilization of CLMs by reaction with their terminal amine groups, using reductive amination chemistry. An alternative route is via plasma polymer layers that contain carboxylic acid groups and using carbodiimnide chemistry. A third route makes use of alkylamme plasma polymer interlayers, which are less process sensitive than aldehyde and acid plasma coatings. A layer of poly-carboxylic acid compounds such as carboxylic acid terminated PAMAM-starburst dendrimers or carboxymethylated dextran is then attached by carbodiimide chemistry onto the amine plasma layer. Amine-terminated CLMs can then be immobilized onto the poly-carboxylic acid layer. Surface analytical methods have been used to characterize the immobilization steps and to assess the surface coverage. Initial cell attachment and growth assays indicate that the biological performance of the CLMs depends on their amino acid sequence.


1985 ◽  
Vol 68 (s10) ◽  
pp. 55s-63s ◽  
Author(s):  
John C. McGrath

1. The effects of varying [Ca2+]o on the contraction of smooth muscle by different α-adrenoceptor agonists were examined on rat isolated anococcygeus muscle. Agonists were tested in the presence of various [Ca2+]o or ‘Ca2+-re-addition curves’ were constructed. In some experiments the [Ca2+]free was buffered with EGTA and nitrilotriacetic acid. The components of the response which were revealed were further analysed by using drugs which modify Ca2+ mobilization. 2. Three separate elements in the contractile response were identified: (i) an initial transient contraction, due to intracellular Ca2+ release could be isolated with [Ca2+]o between 1 nmol/l and 3 μmol/l (this could be obtained only with noradrenaline, phenylephrine and amidephrine); (ii) a nifedipine-sensitive response requiring [Ca2+]o of 3 μmol/l or more; (iii) a nifedipine-resistant response requiring [Ca2+]o of 100 μmol/l or more. Presumably (ii) and (iii) involve the entry of Ca2+o: they could be obtained with all agonists tested, including these above, methoxamine, indanidine and xylazine. 3. The results are discussed in relation to the possibility of distinct types of response and their relationship to subgroups of receptors or agonists. It is concluded that there is a continuous spectrum of activity across the agonist range and that this is likely to correlate with ‘efficacy’ at a single α1 receptor type.


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