Efforts this quarter concentrated on completion and check-out of the MBE system, deposition of ZnS films, analysis of the internal photoresponse for Cu-Cu/sub 2/O cells, and fabrication and characterization of Cu-Cu/sub 2/O solar cells. In-doped ZnS films with very good optical quality and finite conductivity were obtained by co-depositing In and ZnS. Analysis of the internal photoresponse indicated that minority carrier diffusion lengths on the order of 10 ..mu..m are being achieved with the present Cu/sub 2/O growth procedure. Active area values of J/sub PH/ = 8.52 mA/cm/sup 2/ and AM1 Efficiency = 1.76% were achieved for Cu-Cu/sub 2/O cells. These devices appear to have an MIS structure, or fixed charge at the interface. In particular, analysis of I-V data indicates that the current-voltage characteristics for applied voltages greater than 0.3 V are characterized by n approx. = 1 and J/sub 0/ approx. = 2 x 10/sup -9/ mA/cm/sup 2/, which implies an effective barrier height of 0.94 eV compared to the theoretical value of 0.7 eV for a Cu/Cu/sub 2/O Schottky barrier. Another very significant achievement this past quarter was the development of a surface preparation procedure which results in a nearly perfect stochiometry at the surface.

Test data requirements are developed in this memorandum for the one-third scale Ocean Thermal Energy Conversion (OTEC) cold water pipe (CWP) at-sea tests. A major goal of the at-sea tests is to collect sufficient data so that the National Oceanic and Atmospheric Administration (NOAA)/Department of Energy (DOE) CWP Analytic Code can be validated. The code is examined to determine the individual responses requiring verification. The wave environment is then considered for prototype survival and the scaled test. The expected response of the OTEC CWP test article in the test environment is used to form a basis of the test plan. Requirements for the tests of standard configurations of the OTEC CWP test system are first planned followed by requirements for tests of alternate configurations and evolutions. The final product is a set of justified NOAA/CWP analytic code validation requirements.

The ZONE computer program is a finite element mesh generator that produces the nodes and element description of any two-dimensional geometry. The geometry is subdivided into a mesh of quadrilateral and triangular zones arranged sequentially in an ordered march through the geometry. The order of march can be chosen so that the minimum bandwidth is obtained. The node points are defined in terms of the x and y coordinates in a global rectangular coordinate system. The zones generated are quadrilaterals or triangles defined by four node points in a counterclockwise sequence. Node points defining the outside boundary are generated for slide lines and to describe pressure boundary conditions. The mesh that is generated can be used as input to any two dimensional as well as any axisymmetrical structure program. The following points are taken up: program concept and characteristics; regions; layers; meridians (offset, circular arc, ellipse); rays; common characterstics - rays and meridians, ZONE input description; output files; examples; and program availability. Also generated is the input to the program PLOT. 15 figures. (RWR)

Microwave measurements of the ETA accelerating cavities have shown eleven resonances in the frequency range of 0 to 850 MHz. These modes have been identified according to their similarity with the modes of a cylindrical cavity. Measurements of the Q's of the modes yielded values from 14 to 70 and transverse shunt impedances (R/sub perpendicular/Q) of 9 to 12..cap omega... In particular, beam breakup mode (TM/sub 110/) has a Q of 20 to 40 and a transverse impedance of 9..cap omega... A later report will describe proposed modifications to the cavity for the ATA accelerator that reduce the Q's substantially.

The cubic Schroedinger equation (CSE) is ubiquitous as a model equation for the long-time evolution of finite-amplitude near-monochromatic dispersive waves. It incorporates the effects of the radiation field pressure on the constitutive properties of the supporting medium in a self-consistent manner. The properties of the uniformly transiating periodic wave solutions of the one-dimensional CSE are studied here. These (so-called cnoidal) waves are characterized by the values of four parameters. Whitham's averaged variational principle is used to derive a system of quasilinear evolution equations (the modulational equations) for the values of these parameters when they are slowly varying in space and time. Explicit expressions for the characteristic velocities of the modulational equations are obtained for the full set of cnoidal waves. Riemann invariants are obtained for several limits for the stable case, and growth rates are obtained for several limits, including the solitary wave chain, for the unstable case. The results for several nontrivial limiting cases agree with those obtained by independent methods by others. The dynamics of the CSE generalized to two spatial dimensions are studied for the unstable case. A large class of similarity solutions with cylindrical symmetry are obtained systematically using infinitesimal transformation group techniques. The methods are …

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