19 research outputs found
Coagulation Of Wood Pollutants From Model Wastewater By Aluminium Salts
One of the stages of raw material preparation for plywood producing is hydrothermal treatment of birch wood. Wastewater from plywood hydrothermal basin is characterized by the high degree of contamination. The basic contaminating component of this wastewater is lignin, hemicellulose and extractive substances (LES), which are the main reason of a high level of chemical oxygen demand (COD) and color of water. The main objective of the present study is to investigate the influence of aluminium sulfate, aluminium chloride and poly aluminium chloride dose on coagulation of LES from model wastewater. It was established that the influence of coagulant dose on LES removal can be described by 3 regions: first region - the process of coagulation does not take place; second region is characterized by the sharp increase of efficiency of LES removal and the third region corresponds to decrease of efficiency of LES removal at the increase of coagulant dose
The advanced application of the wood-originated wastewater sludge
The wood hydrothermal treatment is one of the plywood production’s stages, which
resulting in the production of wastewater containing such components as hemicelluloses, lignin
and wood extractive substances (HLES). It is necessary to improve the wastewater treatment
technology with the aim to enhance the yield of sludge from plywood wastewater for its effective
and rational recycling. In the present study, the optimal coagulation conditions for the HLES
removal have been found using the developed aluminium salt-based coagulant. The developed
composite coagulant is characterized by lower doses, a wide range of the work pH values, the
insensitivity against temperature changes and a higher coagulation efficacy compared with
traditional aluminium salts. The proposed treatment technology generates many tons of woodoriginated sludge – a biomass coagulate. It was found that the formed coagulate produced in the
process of wastewater treatment can increase the sorption ability of clay. The optimal content of
the dry coagulate in a clay sorbent does not exceed 0.11%. The sorption capacity of the developed
sorbent for water, rapeseed and silicone oil increases by 35%, 31% and 21%, respectively, relative
to the unmodified clay sorbent. The sorption efficiency of heavy metals from water solutions is
also increased by 10–12%. The thermal treatment of the modified clay sorbent at the high
temperature leads to an increase in its sorption capacity for oil products
Structure from motion photogrammetry in forestry : a review
AbstractPurpose of ReviewThe adoption of Structure from Motion photogrammetry (SfM) is transforming the acquisition of three-dimensional (3D) remote sensing (RS) data in forestry. SfM photogrammetry enables surveys with little cost and technical expertise. We present the theoretical principles and practical considerations of this technology and show opportunities that SfM photogrammetry offers for forest practitioners and researchers.Recent FindingsOur examples of key research indicate the successful application of SfM photogrammetry in forestry, in an operational context and in research, delivering results that are comparable to LiDAR surveys. Reviewed studies have identified possibilities for the extraction of biophysical forest parameters from airborne and terrestrial SfM point clouds and derived 2D data in area-based approaches (ABA) and individual tree approaches. Additionally, increases in the spatial and spectral resolution of sensors available for SfM photogrammetry enable forest health assessment and monitoring. The presented research reveals that coherent 3D data and spectral information, as provided by the SfM workflow, promote opportunities to derive both structural and physiological attributes at the individual tree crown (ITC) as well as stand levels.SummaryWe highlight the potential of using unmanned aerial vehicles (UAVs) and consumer-grade cameras for terrestrial SfM-based surveys in forestry. Offering several spatial products from a single sensor, the SfM workflow enables foresters to collect their own fit-for-purpose RS data. With the broad availability of non-expert SfM software, we provide important practical considerations for the collection of quality input image data to enable successful photogrammetric surveys
EVALUATING THE POTENTIAL OF SATELLITE HYPERSPECTRAL RESURS-P DATA FOR FOREST SPECIES CLASSIFICATION
EVALUATING THE POTENTIAL OF SATELLITE HYPERSPECTRAL RESURS-P DATA FOR FOREST SPECIES CLASSIFICATION
Satellite-based hyperspectral sensors provide spectroscopic information in relatively narrow contiguous spectral bands over a large area which can be useful in forestry applications. This study evaluates the potential of satellite hyperspectral Resurs-P data for forest species mapping. Firstly, a comparative study between top of canopy reflectance obtained from the Resurs-P, from the airborne hyperspectral scanner CASI and from field measurement (FieldSpec ASD 4) on selected vegetation cover types is conducted. Secondly, Resurs-P data is tested in classification and verification of different forest species compartments. The results demonstrate that satellite hyperspectral Resurs-P sensor can produce useful informational and show good performance for forest species classification comparable both with forestry map and classification from airborne CASI data, but also indicate that developments in pre-processing steps are still required to improve the mapping level
A Biological Tissue Adhesive and Dissolvent System for Intraocular Tumor Plaque Brachytherapy
Anterior Segment OCTA of Melanocytic Lesions of the Conjunctiva and Iris
PURPOSE: To study the feasibility and diagnostic value of vascular imaging using optical coherence tomography (OCT)-angiography (OCTA) of melanocytic lesions of the conjunctiva and iris.DESIGN: Cross-sectional study.METHODS: Twenty-five patients with an untreated conjunctival lesion (5 melanoma, 13 nevus, 7 primary ac-quired melanosis [PAM]) and 52 patients with an un-treated iris lesion (10 melanoma, 42 nevus) were included. Patients were imaged using a commercially available OCTA device, with the addition of an anterior segment lens and manual focussing. Tumor vessel pres-ence, vascular patterns and vascular density were assessed.RESULTS: Good OCTA images were obtained in 18 of 25 conjunctival lesions and 42 of 52 iris lesions. Failure was caused by lack of patient cooperation, an unfavorable location, or mydriasis. In all imaged conjunctival lesions and 77% of iris lesions, vascular structures were detected. Conjunctival melanoma and nevi demonstrated the same intralesional tortuous patterns, whereas vasculature in eyes with PAM was similar to normal conjunctiva. Both iris melanoma and nevi demonstrated tortuous patterns, distinct from the radially oriented normal iris vasculature.CONCLUSIONS: Optical coherence tomography angiog-raphy (OCTA) allows for noninvasive imaging of the vasculature in melanocytic lesions of the conjunctiva and iris. Good image quality depends highly on patient cooper-ation and lesion characteristics. Differentiation of benign and malignant lesions was not possible. New software is called for to improve image acquisition and analysis.Ophthalmic researc