1,260 research outputs found
Novel fabrication technique for planar glass waveguides
A novel technique has been developed for the deposition of low-loss planar glass waveguides by directly spin coating from the liquid, thus overcoming the problems of reproducing glass stoichiometry when depositing from the vapour
United Kingdom Minerals Yearbook 2015: statistical data to 2014
The United Kingdom Minerals Yearbook is an annual publication providing comprehensive statistical data on minerals production, consumption and trade, and includes commentary on the UK's minerals industry.
It contains:
• essential guidance for decision makers
• reliable and up–to–date information
• authoritative commentary on current developments
It is of value to all those interested in the many facets of Britain's minerals industry and its contribution to the national economy. This publication forms part of Britain's continuous mining and quarrying record
Theoretical analysis of the focusing of acoustic waves by two-dimensional sonic crystals
Motivated by a recent experiment on acoustic lenses, we perform numerical
calculations based on a multiple scattering technique to investigate the
focusing of acoustic waves with sonic crystals formed by rigid cylinders in
air. The focusing effects for crystals of various shapes are examined. The
dependance of the focusing length on the filling factor is also studied. It is
observed that both the shape and filling factor play a crucial role in
controlling the focusing. Furthermore, the robustness of the focusing against
disorders is studied. The results show that the sensitivity of the focusing
behavior depends on the strength of positional disorders. The theoretical
results compare favorably with the experimental observations, reported by
Cervera, et al. (Phys. Rev. Lett. 88, 023902 (2002)).Comment: 8 figure
Connecting Disasters and Climate Change to the Humanitarian-Development-Peace Nexus
publishedVersionPaid Open Acces
European Mineral Statistics 2010-14: a product of the World Mineral statistics database
European Mineral Statistics provides statistical information about minerals and metals in Europe. It provides the essential background intelligence for any European minerals-related activities.
Production, export and import tables are presented for all EU members and EU candidate countries, plus Norway and Switzerland, in two sections:
•by individual country
•by commodity, with bullets on salient features and graphics
More than 70 different mineral commodities are included from Aluminium to Zirconium, plus statistics relating to primary aggregates and cement.
The book also includes commentary discussing the different categories of minerals – construction minerals, industrial minerals, metals and energy minerals – in the European context and contains general information on the compilation of data
World Mineral Production 2011-15
The latest edition of this annual publication from the British Geological Survey (BGS). This volume contains mineral production statistics for the five year period from 2011 to 2015, for more than 70 mineral commodities, by country worldwide. It is the latest publication from the World Mineral Statistics dataset which began in 1913. The information contained in the dataset, and associated publications, is compiled from a wide range of sources: home and overseas government departments, national statistical offices, specialist commodity authorities, company reports, and a network of contacts throughout the world. The database compilers aim for integrity and accuracy in the data and, for quality control purposes, participate in international specialist groups, and maintain close links with other mineral statistics providers in Europe and North America
Locating current sheets in the solar corona
Current sheets are essential for energy dissipation in the solar corona, in
particular by enabling magnetic reconnection. Unfortunately, sufficiently thin
current sheets cannot be resolved observationally and the theory of their
formation is an unresolved issue as well. We consider two predictors of coronal
current concentrations, both based on geometrical or even topological
properties of a force free coronal magnetic field. First, there are
separatrices related to magnetic nulls. Through separatrices the magnetic
connectivity changes discontinuously. Coronal magnetic nulls are, however, very
rare. At second, inspired by the concept of generalized magnetic reconnection
without nulls, quasi-separatrix layers (QSL) were suggested. Through QSL the
magnetic connectivity changes continuously, though strongly. The strength of
the connectivity change can be quantified by measuring the squashing of the
flux tubes which connect the magnetically conjugated photospheres.
We verify the QSL and separatrix concepts by comparing the sites of magnetic
nulls and enhanced squashing with the location of current concentrations in the
corona. Due to the known difficulties of their direct observation we simulated
the coronal current sheets by numerically calculating the response of the
corona to energy input from the photosphere heating a simultaneously observed
EUV Bright Point. We did not find coronal current sheets not at the
separatrices but at several QSL locations. The reason is that although the
geometrical properties of force free extrapolated magnetic fields can indeed,
hint at possible current concentrations, a necessary condition for current
sheet formation is the local energy input into the corona
World Mineral Production 2012-16
The latest edition of this annual publication from the British Geological Survey (BGS) is now available to download. This volume contains mineral production statistics for the five year period from 2012 to 2016, for more than 70 mineral commodities, by country worldwide. Additional tables containing European production of aggregates and cement are included as an Appendix.
It is the latest publication from the World Mineral Statistics dataset which began in 1913. The information contained in the dataset, and associated publications, is compiled from a wide range of sources: home and overseas government departments, national statistical offices, specialist commodity authorities, company reports, and a network of contacts throughout the world
World Mineral Production 2009-13
The latest edition of this annual publication from the British Geological Survey (BGS) is now available to download. This volume contains mineral production statistics for the five year period from 2009 to 2013, for more than 70 mineral commodities, by country worldwide.
It is the latest publication from the World Mineral Statistics dataset which began in 1913. The information contained in the dataset, and associated publications, is compiled from a wide range of sources: home and overseas government departments, national statistical offices, specialist commodity authorities, company reports, and a network of contacts throughout the world.
The database compilers aim for integrity and accuracy in the data and, for quality control purposes, participate in international specialist groups, and maintain close links with other mineral statistics providers in Europe and North America. The data provides essential mineral intelligence for:
• security of supply issues
• economic analyses
• environmental issues
• sustainable development planning
• regulation and policy issues
• commercial strategic planning
The data are available in the following formats:
• Annual publication of “World Mineral Production” and its predecessors, which can be downloaded in pdf from our World Archive
• MS Excel for years from 1992 via our data download tool
• The most recent editions are available to purchase in hard copy from the BGS online shop
• One off reports such as those shown lower down this page, available for download in pd
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