285 research outputs found
Productivity of a prototype truck-mounted logging residue bundler and a road-side bundling system
When recovering logging residues (LR) for bioenergy its density should be increased before road transport, otherwise a low proportion of the trucks’ load capacity will be used. One way this can be currently done is to compress LR into bundles that are forwarded to roadside
landing. A less well-developed alternative is to forward loose LR and bundle it at landing. In the presented study, a prototype specifically developed for road-side bundling was found to produce larger, heavier bundles than bundling machinery intended for in-field use (mean length, diameter and raw bulk density 4.7 m, 0.8 m and 285 kg m–3, respectively, with 299–445 kg oven dry matter per bundle). The machine was a so at least 30% more productive than
previously described in-field bundling systems, producing 14–19 bundles per productive work hour (PWh), equivalent to 5.2–7.8 oven-dry tonnes PWh–1. Bundles were estimated to use 67–86% of an LR truck’s 30 tonnes load capacity, similar to proportions used when transporting loose LR. However, a continuous feeding and compressing process would probably almost double productivity, while longer bundles would enable full use of truck load capacity. With such improvements bundling at road-side could provide a viable alternative to current LR-recovering systems
Ethynylbenzene monolayers on gold: A metal-molecule binding motif derived from a hydrocarbon
Exposure of a Au(111) surface to ethynylbenzene in solution leads to the formation of a bound monolayer. A chemisorption process occurs to give a stable layer consisting of oxygen-containing hydrocarbon species. Ethynylbenzene itself does not oxidize under the deposition conditions indicating that the gold surface facilitates the oxidation process. Calculations show that ethynylbenzene and its oxidation products phenylacetic acid and phenyloxirane have positive binding energies to the gold surface. 1,4-Diethynylbenzene also binds to Au(111) and anchors gold nanoparticles deposited from solution to form dense, semiregular arrays. © 2007 American Chemical Society
ON INTEGRATION OF EVOLVING INFRASTRUCTURE TOPOLOGY GRAPHS AND METRIC DATA STREAMS IN INFORMATION TECHNOLOGY INFRASTRUCTURE MANAGEMENT
Modern cloud-based information technology (IT) infrastructure monitoring context and data are gathered from various systems. Typical monitoring systems provide a set of metrics characterizing the performance and health of a variety of infrastructure components. To understand the dependencies and relations among these measurements, the infrastructure topology can be analysed to provide context to the monitoring metrics. However, the metrics and the topology are updated at different time intervals and providing continuous merging and analysis of both data sets is a challenging task which is rarely addressed in the scientific literature. The paper elaborates a method for integration of infrastructure topology graph and monitoring metric data streams. The method is intended for application in the identification of anomalies in IT infrastructure.
Intra-annual height growth dynamics of Scots and lodgepole pines and its relationship with meteorological parameters in central Latvia
The Scots pine (Pinus sylvestris L.) is the second-most widely used tree species in
forestry in Latvia and is the only species used for afforestation on nutrient poor soils that cover
considerable forest land in Latvia. Several studies have shown that, in such conditions, the
lodgepole pine (Pinus contorta var. latifolia) may be more productive in terms of biomass and
yield. It is important to consider climate change studies to assess the potential for a larger-scale
use of the lodgepole pine in forestry. The aim was to assess the intra-annual height growth
patterns of both species, the differences between them, and the influence of meteorological
parameters on their height growth. Their height growth was monitored on a weekly basis in two
sampling sites in central Latvia, and the height increment curves were described by Gompertz’s
model. The height growth dynamics of individual trees and species differed notably, indicating
the potential for the selection of the best-adapted genotypes. Our results indicate that the early
onset of the active growth phase might be the most important factor determining the total height
increment for both species. Temperature-related meteorological parameters were the only ones
with a statistically significant influence on pines height growth and only when at least one of the
variables were standardised prior to the analysis. A temperature increase had a slightly stronger
positive effect on the growth of the lodgepole pine, indicating that it might be suitable for more
intensive use in forestry under the climate change scenarios for Latvia
Effect of stem rot on wood basic density, carbon, and nitrogen content of living deciduous trees in hemiboreal forests
While numerous studies have focused on analyzing various aspects of the carbon (C) budget in forests, there appears to be a lack of comprehensive assessments specifically addressing the impact of stem rot on the C budget of broadleaf tree species, especially in old-growth forests where stem rot is prevalent. One of the main challenges in accurately quantifying C losses caused by stem rot is the lack of precise data on the basic density and C content of decayed wood, which are crucial for converting decayed wood volume into biomass and C stocks. Using linear mixed-effects models, we examine the variability of wood basic density, C content, and nitrogen (N) content. Discolored and decomposed wood was collected from the stems of 136 living deciduous trees common in hemiboreal forests in Latvia. Our research indicates a noticeable reduction in the wood basic density, coupled with an increase in the N content within the stem wood throughout the decomposition process in birch (Betula spp.), European aspen (Populus tremula L.), grey alder (Alnus incana (L.) Moench), and common alder (Alnus glutinosa (L.) Gaertn.). While aspen wood showed a decreasing trend in C content as decay progressed, a pairwise comparison test revealed no significant differences in C content between discolored and decomposed wood for the studied species, unlike the findings for basic density and N content. This study emphasizes the need to account for stem rot in old-growth forest carbon budgets, especially in broadleaf species, and calls for more research on stem rot-induced carbon losses
Greater insight into the MTDSC technique involving fundamental sinusoidal heat flow equations
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45th Annual Larval Fish Conference & 13th International Larval Biology Symposium San Diego, California 29 August – 1 September, 2022
INDITU
Windblown Lead Carbonate as the Main Source of Lead in Blood of Children from a Seaside Community: An Example of Local Birds as “Canaries in the Mine”
Background: In late 2006, the seaside community in Esperance, Western Australia, was alerted to thousands of native bird species dying. The source of the lead was thought to derive from the handling of Pb carbonate concentrate from the Magellan mine through the port of Esperance, begun in July 2005. Concern was expressed for the impact of this process on the community. Objective: This study was designed to evaluate the source of Pb in blood of a random sample of the community using Pb isotope ratios. Methods: The cohort comprised 49 children (48 20 years of age) with a bias toward higher blood lead (PbB) values to facilitate source identification. Results: Mean PbB level of the children was 7.5 μg/dL (range, 1.5-25.7 μg/dL; n = 49; geometric mean, 6.6 μg/dL), with four children whose PbB was > 12 μg/dL. The isotopic data for blood samples lay around two distinct arrays. The blood of all children analyzed for Pb isotopes contained a contribution of Pb from the Magellan mine, which for young children ranged from 27% up to 93% (mean, 64%; median, 71%). Subtraction of the ore component gave a mean background PbB of 2.3 μg/dL. Several children whose PbB was > 9 μg/dL and most of the older subjects have complex sources of Pb. Conclusions: The death of the birds acted as a sentinel event; otherwise, the exposure of the community, arising from such a toxic form of Pb, could have been tragic. Isotopic data and mineralogic and particle size analyses indicate that, apart from the recognized pathway of Pb exposure by hand-to-mouth activity in children, the inhalation pathway could have been a significant contributor to PbB for some of the very young children and in some parents.7 page(s
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