Report on Mini-conference on Sludge Disposal Alternatives in the Ocean off Southern California, 8 September 1976

The purpose of the conference was to review the status of our capability to predict the environmental effects of the disposal of digested sewage sludge in the ocean off the coast of Southern California. At present, the ocean disposal of sewage sludge is prohibited by State and Federal regulations. Ocean disposal of sludge, however, is a complex of many alternative combinations of what, where and how; and the environmental consequences of all such combinations have not yet been determined. There is, in fact, some evidence that at least one environmentally sound mode of sludge disposal in the ocean off the Southern California coast may exist. This is the trapping of sludge in the sediments of deep, nearshore ocean basins. such as the Santa Monica Basin. Details of this method are given in Section 3.3. p. 12. It is the philosophy of the Environmental Quality Laboratory to study and evaluate policy alternatives but not to be an advocate of one alternative or another. Some of the policies studied may be contrary to existing laws or regulations, but it is believed that there is a better chance for improvement in the laws or regulations if alternatives currently outside them are also studied. The conference was sponsored by the Environmental Quality Laboratory in the belief that sufficient information is now available to begin making reasonable estimates of the environmental consequences of existing or alternative ocean disposal methods in order to compare them to land-based disposal methods. The purpose of this report is not to publish the actual proceedings of the conference. but rather to act as a communications aid. It is intended to publicize the issues that were raised at the conference, to give the names and addresses of people who are involved in these issues, and to present abstracts and literature citations. The schedule of the conference is presented in the next section. It is followed by a section containing abstracts of current research by conference attendees along with reference lists supplied by them. The fourth section is a summary of the afternoon discussion sessions. The final section is a list of conference attendees with their mailing addresses

Violation of Kohler's rule by the magnetoresistance of a quasi-two-dimensional organic metal

The interlayer magnetoresistance of the quasi-two-dimensional metal $\alpha$-(BEDT-TTF)$_2$KHg(SCN)$_4$ is considered. In the temperature range from 0.5 to 10 K and for fields up to 10 tesla the magnetoresistance has a stronger temperature dependence than the zero-field resistance. Consequently Kohler's rule is not obeyed for any range of temperatures or fields. This means that the magnetoresistance cannot be described in terms of semiclassical transport on a single Fermi surface with a single scattering time. Possible explanations for the violations of Kohler's rule are considered, both within the framework of semi-classical transport theory and involving incoherent interlayer transport. The issues considered are similar to those raised by the magnetotransport of the cuprate superconductors.Comment: 5 pages, RevTeX + epsf, 2 figures. Slightly revised version to appear in Physical Review B, May 15, 199

A holistic multimodal approach to the non-invasive analysis of watercolour paintings

A holistic approach using non-invasive multimodal imaging and spectroscopic techniques to study the materials (pigments, drawing materials and paper) and painting techniques of watercolour paintings is presented. The non-invasive imaging and spectroscopic techniques include VIS-NIR reflectance spectroscopy and multispectral imaging, micro-Raman spectroscopy, X-ray fluorescence spectroscopy (XRF) and optical coherence tomography (OCT). The three spectroscopic techniques complement each other in pigment identification. Multispectral imaging (near infrared bands), OCT and micro-Raman complement each other in the visualisation and identification of the drawing material. OCT probes the microstructure and light scattering properties of the substrate while XRF detects the elemental composition that indicates the sizing methods and the filler content . The multiple techniques were applied in a study of forty six 19th century Chinese export watercolours from the Victoria & Albert Museum (V&A) and the Royal Horticultural Society (RHS) to examine to what extent the non-invasive analysis techniques employed complement each other and how much useful information about the paintings can be extracted to address art conservation and history questions

Can One Hear the Shape of a Graph?

We show that the spectrum of the Schrodinger operator on a finite, metric graph determines uniquely the connectivity matrix and the bond lengths, provided that the lengths are non-commensurate and the connectivity is simple (no parallel bonds between vertices and no loops connecting a vertex to itself). That is, one can hear the shape of the graph! We also consider a related inversion problem: A compact graph can be converted into a scattering system by attaching to its vertices leads to infinity. We show that the scattering phase determines uniquely the compact part of the graph, under similar conditions as above.Comment: 9 pages, 1 figur