An Analysis of the Full-Floating Journal Bearing

An analysis of the operating characteristics of a full-floating bearing - a bearing in which a floating sleeve is located between the journal and bearing surfaces - is presented together with charts - from which the performance of such bearings may be predicted. Examples are presented to illustrate the use of these charts and a limited number of experiments conducted upon a glass full-floating bearing to verify some results of the analysis are reported. The floating sleeve can operate over a wide range of speeds for a given shaft speed, the exact value depending principally upon the ratio of clearances and upon the ratio of radii of the bearing. Lower operating temperatures at high rotative speeds are to be expected by using a full-floating bearing. This lower operating temperature would be obtained at the expense of the load-carrying capacity of the bearing if, for comparison, the clearances remain the same in both bearings. A full-floating bearing having the same load capacity as a conventional journal bearing may be designed if decreased clearances are allowable

A developmental cascade model for early adolescent onset substance use: The role of early childhood stress

Contains fulltext : 199688.pdf (publisher's version ) (Open Access)Backgrounds and aims: Despite the link between stress and addictive behavior in adulthood, little is known about how early life stress in families predicts the early emergence of substance use in adolescence. This study tested a developmental cascade model, proposing that early stressful life events and negative parent-child interaction covary, and both disrupt the refinement of inhibitory control, which evolves into problem behavior in middle/late childhood and subsequent substance use exploration in early adolescence. Methods: Data came from the Early Steps Multisite study, a community sample of at-risk families in the metropolitan US areas of Pittsburgh (Pennsylvania), Eugene (Oregon), and Charlottesville (Virginia) with children aged 2 at the start of the study and 14 at the last measurement (N = 364). Structural equation modeling was used to test the proposed model. Results: Early stressful life events and negative parent-child interaction assessed at ages 2 to 5 were negatively related to inhibitory control at ages 7 and 8. Low levels of inhibitory control were prognostic of childhood problem behavior at ages 9 and 10. Finally, late childhood problem behavior was associated with substance use at age 14. Parental drug use was directly related to substance use at age 14. Conclusions: Early life stress may disrupt child inhibitory control, which can cascade into behavioral and peer problem behavior in childhood and, in turn, heighten the risk for early adolescent substance use.9 p

Computational investigations of dispersion interactions between small molecules and graphene-like flakes

We investigate dispersion interactions in a selection of atomic, molecular, and molecule–surface systems, comparing high-level correlated methods with empirically corrected density functional theory (DFT). We assess the efficacy of functionals commonly used for surface-based calculations, with and without the D3 correction of Grimme. We find that the inclusion of the correction is essential to get meaningful results, but there is otherwise little to distinguish between the functionals. We also present coupled-cluster quality interaction curves for H2, NO2, H2O, and Ar interacting with large carbon flakes, acting as models for graphene surfaces, using novel absolutely localized molecular orbital based methods. These calculations demonstrate that the problems with empirically corrected DFT when investigating dispersion appear to compound as the system size increases, with important implications for future computational studies of molecule–surface interactions

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

Safety of Arch Aortography for Assessment of Carotid Arteries

AbstractPurposeTo retrospectively review the safety of arch aortography and compare complication rates with published figures for selective catheter angiography.MethodsThe medical records of patients undergoing arch aortography over the last 3 years (n=311; 180 male, 131 female; mean±SD age 71.0±9.2 years, range 42–90 years) were retrospectively reviewed. Any peri-procedural (0–48h) complications were recorded. A certified neurologist (MSR/GSV) classified all questionable neurological events.ResultsThere were no focal neurological events or deaths (n=0; 0%; CI: 0–0.96%). Non-focal neurological events included mild disorientation (n=2; 0.6%; CI: 0.176–2.31) and unequal pupils (n=1; 0.3%; CI: 0.056–1.79%). Cardiovascular events included symptomatic hypotension (n=4; 1.3%; CI: 0.50–3.25%), angina (n=1; 0.3%; CI: 0.056–1.79%) and arrhythmia (n=4; 1.3%; CI: 0.50–3.25). There were 27 minor access site complications (8.7%; CI: 6.0–12.3). None of these complications extended hospital stay. None of the arch angiograms had to be followed by selective carotid angiography.ConclusionArch aortography appears to have a lower neurological complication rate than selective carotid angiography

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