Bacillaene, a novel polyene antibiotic, was discovered and isolated from fermentation broths of a strain of Bacillus subtilis. The novel antibiotic has a nominal molecular weight of 580 and an empirical formula of C3 5H48O7.Bacillaene is active against a broad spectrum of bacteria in agar-plate diffusion assays. Studies in vitro indicate that the antibiotic inhibits prokaryotic protein synthesis but not eukaryotic protein synthesis. Cell survival studies performed with strains of Escherichia coli indicate that the antibiotic is a bacteriostatic agent.

A method is presented for the deposition of CdS thin films of 0.05–0.7 μm thickness from solutions at 50–70 °C containing citratocadmium(II) complex ions and thiourea. The films show an optical band gap Eg≳2.6 eV. Optical transmittance is about 80% for photon energy <Eg. The dark conductivity of the films is of the order of 10−8 Ω−1 cm−1. The photosensitivity of these films is high, 106–107 under illumination with tungsten halogen light of 1 kW m−2. Annealing in air at 400–500 °C for 1 h converts the films to n type. It is possible to obtain sheet resistances of about 150 Ω for a 0.2 μm film (i.e., conductivity of 300 Ω−1 cm−1) by this process. Conversion of the films to n type is possible also by immersing the film in a 0.01 M HgCl2 solution for 15 min followed by air annealing for 1 h at 200 °C. The films show n-type dark conductivity of ≂0.05 Ω−1 cm−1 and photoconductivity of ≂1 Ω−1 cm−1. X-ray diffraction and x-ray photoelectron spectroscopic depth profile studies on the films show that the modification of the electrical characteristics is brought about through changes in composition of the surface layers in the films.

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Formation of the ternary compound Cu3BiS3 during annealing of chemically deposited CuS (∼0.3 μm) films on Bi2S3 film (∼0.1 μm on glass substrate) is reported. The interfacial atomic diffusion leading to the formation of the compound during the annealing is indicated in x-ray photoelectron depth profile spectra of the films. The formation of Cu3BiS3 (Wittichenite, JCPDS 9-488) is confirmed by the x-ray diffraction (XRD) patterns. The films are optically absorbing in the entire visible region (absorption coefficient 4 × 104 cm−1 at 2.48 eV or 0.50 μm) and are p-type with electrical conductivity of 102−103 Ω−1 cm−1. Potential applications of these films as optical coatings in the control of solar energy transmittance through glazings and as a p-type absorber film in solar cell structures are indicated.