Volume 4, Issue 5
December 1982, pages 483-601
pp 483-526 December 1982 Review Papers
An overview of the semiconductor based photoelectrochemical (pec) cells for solar energy conversion is presented.pec cells are of two types: photoelectrolysis cells and photovoltaic cells. The principles involved, electrode and electrode/electrolyte interface characteristics, experimental methods of investigation and energy conversion efficiency are discussed in detail. Up-to-date data on variouspec cells are also presented and discussed.
pp 527-548 December 1982 Review Papers
An attempt has been made in this review to cover the existing information on the growth of single crystals in gels. Preparation of various types of gels, in which crystals can be grown, has been briefly described. The growth of single crystals from gels is reviewed using the following classifications: (i) Crystal growth by reaction. (ii) Crystallization by complex dilution method. (iii) Crystal growth by reduction of solubility. A compact list of some important crystals grown in gels is given. Growth mechanism and nucleation problems are discussed. Morphologies of various gel-grown crystals are described. Researches on gel-grown single crystals are also briefly described.
pp 549-561 December 1982 Research Report
Rapid solidification of metallic melts at a rate ≳105 °K/sec has gained considerable interest for casting non-equlibrium crystalline structures in general and metallic glasses in particular. Of the variety of techniques used for rapid solidification, melt-spinning and melt-extraction are widely used. This paper describes the design and development of a melt-spinning technique in our laboratory. Optimization of spinning parameters for smooth and continuous ribbons is discussed. Glassy ribhons of Cu-Zr and Pd-Ge alloys have been made under optimized conditions. A brief account of some of the structural and electronic properties of these glasses is illustrated.
pp 563-568 December 1982 Articles
Silver chlorate crystallizes in the tetragonal system at room temperature. The crystal undergoes a reversible first order phase tronsition to a cubic phase at 139°C. The transition temperature along with the enthalpy change was determined by thedsc technique and the change of enthalpy was found to be 3·12 cal/g. The high temperature form as determined by x-ray powder diffractometric method was found to be primitive cubic with a lattice constant of 6·681 Å at 145°C.
pp 569-573 December 1982 Articles
The nature of deformation of anhydrous diglycine-sulphate has been studied. Static and dynamic indentations were employed to deform the crystal. The slip and fracture modes of deformation occurring in the crystal have been identified.
pp 575-577 December 1982 Articles
Ferroelectric polymer films have been made by dispersingtgs powder. The dielectric constant ε′ of the films has been measured. The thermal behaviour of ε′ is also reported. Data have been obtained from samples prepared with different weight concentrations (10–75%) oftgs.
pp 579-582 December 1982 Articles
The Seebeck voltage of the ceramic solid solutions of the system Pb2−x Lax Li0·5 Nb1·5 O6+δ has been studied as a function of temperature and concentration of lanthanum. The thermoelectric power was strongly dependent on the temperature and doping amount of lanthanum.
pp 583-587 December 1982 Articles
Synthesis and characterisation bynmr spectroscopy of oligomers derived from 2-hydroxy ethyl acrylate (hea) and 2-hydroxy propyl methacrylate (hpma) and 1,6-bexamethylene diisocyanate (hdi) are briefly discussed.
pp 589-593 December 1982 Articles
Surface distortion features around static indents on the cleavages of CaF2 single crystals have been investigated by multiple beam interference technique. At room temperature microcracks around such indents nucleate at the sinking in regions. Fizeau fringe patterns (around indents at 200° C) revealed a transition from a three-fold to a six-fold material flow.
pp 595-601 December 1982 Articles
The effect of temperature and processing history on the flow stress of a two-phase aluminium (Al-6% Cu) alloy was investigated. The flow stress was determined from the changes in dimensions of flat, ring-shaped specimens using Avitzur’s upper bound theorem. The results indicate that the flow stress increases with the degree of deformation irrespective of the specimen history considered and this tendency is in general more pronounced at large deformations. The flow stress of this alloy at large deformation is considerably lower at 573 K than at the lower temperatures tested. The morphology and distribution of the second phase particles of this alloy changed considerably depending upon the processing history, temperature and deformation.
Volume 42 | Issue 5
Click here for Editorial Note on CAP Mode