Results for “WOOD” — Page 39

NASA NTRS2021

Discrete anisotropic radiative transfer modelling of solar-induced chlorophyll fluorescence: Structural impacts in geometrically explicit vegetation canopies

Solar-induced fluorescence (SIF) is a subtle but informative optical signal of vegetation photosynthesis. Remotely sensed SIF integrates environmental, physiological and structural changes that alter photosynthesis at leaf, plant and canopy scales. Radiative transfer models are ideally suited to investigate the complex sources of variability in the SIF signal to guide the interpretation of SIF retrievals from airborne and space-borne platforms. Here, we coupled the Fluspect-Cx model of leaf optical properties and chlorophyll-a fluorescence with the Discrete Anisotropic Radiative Transfer (DART) model to upscale SIF from individual leaves to three-dimensional (3D) structurally explicit canopies. For one-dimensional homogeneous (turbid-like) canopies, DART-SIF was nearly identical to SIF simulated in two existing models, SCOPE and mSCOPE (RMSE <0.221 W./sq.m.μm.sr). DART simulations in geometrically explicit 3D canopies offered four important insights regarding the influence of vegetation structure on the multi-angular top-of-canopy SIF signal. First, changes in the 3D canopy architecture of maize crops, represented by leaf density (leaf area index), and plant clumping (canopy closure) had a larger impact on SIF than the modelled photosynthetic efficiency distinction between sun-adapted and shade-adapted foliage. Second, clumping of leaves at the crop and stand levels was identified as one of the key driving factors of multi-angular anisotropy of red and far-red SIF (686 and 740 nm) for both maize and eucalyptus canopies. Third, non-photosynthetic woody material had a significant impact on top-of-canopy SIF in modelled 3D forest stands. Wood shadowing decreased the photosynthetically active radiation absorbed by green leaves, and consequently the SIF emissions, by 10% in sparse and 17% in dense eucalyptus stands. The wood obstruction (blocking) effect, quantified as a relative difference of SIF escape probabilities from canopies with and without wood in the nadir viewing direction, decreased far-red SIF by 4–6% but it had a smaller and sometimes positive influence (by less than 2%) on red SIF. Fourth, DART 3D radiative budget profiles revealed that the majority of the SIF signal from a dense eucalyptus stand originated from the top 25% of the simulated canopy. Interestingly, the introduction of bark-covered woody elements did not alter the simulated balance and omnidirectional escape factor of red SIF in this upper canopy part but did raise significantly both of them in case of far-red SIF. These results demonstrate the importance of 3D radiative transfer and radiative budget simulations for investigating SIF interactions in structurally complex plant canopies and for a better understanding of spatiotemporal and multi-angular remote sensing SIF observations.

Zbyněk Malenovský↗

DOE OSTI2013

Xylanases, nucleic acids encoding them and methods for making and using them

The invention relates to enzymes having xylanase, mannanase and/or glucanase activity, e.g., catalyzing hydrolysis of internal .beta.-1,4-xylosidic linkages or endo-.beta.-1,4-glucanase linkages; and/or degrading a linear polysaccharide beta-1,4-xylan into xylose. Thus, the invention provides methods and processes for breaking down hemicellulose, which is a major component of the cell wall of plants, including methods and processes for hydrolyzing hemicelluloses in any plant or wood or wood product, wood waste, paper pulp, paper product or paper waste or byproduct. In addition, methods of designing new xylanases, mannanases and/or glucanases and methods of use thereof are also provided. The xylanases, mannanases and/or glucanases have increased activity and stability at increased pH and temperature.

59 BASIC BIOLOGICAL SCIENCES↗

DOE OSTI2014

Process for decomposing lignin in biomass

A mild inexpensive process for treating lignocellulosic biomass involves oxidative delignification of wood using an aqueous solution prepared by dissolving a catalytic amount of manganese (III) acetate into water and adding hydrogen peroxide. Within 4 days and without agitation, the solution was used to convert poplar wood sections into a fine powder-like delignified, cellulose rich materials that included individual wood cells.

59 BASIC BIOLOGICAL SCIENCES↗

DOE OSTI2016

Building America Case Study: Advanced Extended Plate and Beam Wall System in a Cold-Climate House, Mount Joy, Pennsylvania

This report presents the design and evaluation of a innovative wall system. This highly insulated (high-R) light-frame wall system for use above grade in residential buildings is referred to as Extended Plate & Beam (EP&B). The EP&B design is the first of its kind to be featured in a new construction test house (NCTH) for the DOE Building America program. The EP&B wall design integrates standard building methods and common building products to construct a high-R wall that minimizes transition risks and costs to builders. The EP&B design combines optimized framing with integrated rigid foam sheathing to increase the wall system's R-value and reduce thermal bridging. The foam sheathing is installed between the wall studs and structural wood sheathing. The exterior wood sheathing is attached directly to a framing extension formed by extended top and bottom plates. The exterior wood sheathing can dry to the exterior and provides bracing, a clear drainage plane and flashing surface for window and door openings, and a nailing surface for siding attachment. With support of the DOE Building America program, Home Innovation Research Labs partnered with Lancaster County Career and Technology Center (LCCTC) to build a NCTH in Lancaster, PA to demonstrate the EP&B wall design in a cold climate (IECC climate zone 5A). The results of the study confirmed the benefits of the systems and the viability of its integration into the house construction process.

32 ENERGY CONSERVATION, CONSUMPTION, AND UTILIZATI↗

DOE OSTI2013

Comparative Analysis of 35 Basidiomycete Genomes Reveals Diversity and Uniqueness of the Phylum

Fungi of the phylum Basidiomycota (basidiomycetes), make up some 37percent of the described fungi, and are important in forestry, agriculture, medicine, and bioenergy. This diverse phylum includes symbionts, pathogens, and saprobes including wood decaying fungi. To better understand the diversity of this phylum we compared the genomes of 35 basidiomycete fungi including 6 newly sequenced genomes. The genomes of basidiomycetes span extremes of genome size, gene number, and repeat content. A phylogenetic tree of Basidiomycota was generated using the Phyldog software, which uses all available protein sequence data to simultaneously infer gene and species trees. Analysis of core genes reveals that some 48percent of basidiomycete proteins are unique to the phylum with nearly half of those (22percent) comprising proteins found in only one organism. Phylogenetic patterns of plant biomass-degrading genes suggest a continuum rather than a sharp dichotomy between the white rot and brown rot modes of wood decay among the members of Agaricomycotina subphylum. There is a correlation of the profile of certain gene families to nutritional mode in Agaricomycotina. Based on phylogenetically-informed PCA analysis of such profiles, we predict that that Botryobasidium botryosum and Jaapia argillacea have properties similar to white rot species, although neither has liginolytic class II fungal peroxidases. Furthermore, we find that both fungi exhibit wood decay with white rot-like characteristics in growth assays. Analysis of the rate of discovery of proteins with no or few homologs suggests the high value of continued sequencing of basidiomycete fungi.

59 BASIC BIOLOGICAL SCIENCES↗

DOE OSTI2017

Compositions and methods for xylem-specific expression in plant cells

The invention provides promoter sequences that regulate specific expression of operably linked sequences in developing xylem cells and/or in developing xylem tissue. The developing xylem-specific sequences are exemplified by the DX5, DX8, DX11, and DX15 promoters, portions thereof, and homologs thereof. The invention further provides expression vectors, cells, tissues and plants that contain the invention's sequences. The compositions of the invention and methods of using them are useful in, for example, improving the quantity (biomass) and/or the quality (wood density, lignin content, sugar content etc.) of expressed biomass feedstock products that may be used for bioenergy, biorefinary, and generating wood products such as pulp, paper, and solid wood.

59 BASIC BIOLOGICAL SCIENCES↗

DOE OSTI2018

Xylanases, nucleic acids encoding them and methods for making and using them

The invention relates to enzymes having xylanase, mannanase and/or glucanase activity, e.g., catalyzing hydrolysis of internal .beta.-1,4-xylosidic linkages or endo-.beta.-1,4-glucanase linkages; and/or degrading a linear polysaccharide beta-1,4-xylan into xylose. Thus, the invention provides methods and processes for breaking down hemicellulose, which is a major component of the cell wall of plants, including methods and processes for hydrolyzing hemicelluloses in any plant or wood or wood product, wood waste, paper pulp, paper product or paper waste or byproduct. In addition, methods of designing new xylanases, mannanases and/or glucanases and methods of use thereof are also provided. The xylanases, mannanases and/or glucanases have increased activity and stability at increased pH and temperature.

59 BASIC BIOLOGICAL SCIENCES↗

DOE OSTI2016

Chapter 4 - Environmental Sustainability Aspects of Forest Biomass Mobilisation. In the book Mobilisation of Forest Bioenergy in the Boreal and Temperate Biomes

The environmental sustainability of forest biomass procurement needs to be well understood, as the capacity of ecosystems to provide biomass without negative impacts on ecological functioning limits the biomass potential. Emerging bioenergy markets typically first take advantage of secondary residue streams of various wood processing industries and tertiary end-of-life residues. The use of these secondary and tertiary wood resources is not likely to compromise the environmental sustainability of forests. When these resources in any region become scarce or fully utilized, primary residues (i.e., by-products of forestry harvesting operations and silvicultural practices) such as branches, tops, and non-merchantable trees become increasingly targeted as feedstock sources. Forest biomass procurement in the boreal and temperate biomes should therefore not be analyzed as a stand-alone activity, but rather as an intensification of land use and of forest management, in which tree parts and trees are harvested in addition to conventional forest product fractions. Thus, principles of protection and sustainability should remain the same whether forests are managed for conventional forest products only or also for biomass for energy. Some modifications may be needed to properly identify and find mitigation strategies for sensitive conditions where field evidence suggests that the incremental removal of biomass or other forms of intensive management may not be sustainable. Silvicultural practices such as fertilization, competition control, and soil preparation are options to manage the microenvironment, tree growing conditions, and prevent or mitigate negative impacts. Moreover, landscape management regulations should be put in place to ensure that sufficient biodiversity-important features such as dead wood, aging stands, corridors, etc. are preserved. Special attention should then be directed to trees and stands with high biodiversity values or those important for maintaining ecosystem services which, without a bioenergy market, would have been left uncut. Applying the concept of adaptive forest management, ecological monitoring following harvesting operations, scientific field testing and modeling should be combined to produce better knowledge that could help improve practices. The forestry sector needs to start adapting to a future situation where it is expected to provide conventional forest products, biomaterials and bioenergy. To achieve this, good governance mechanisms such as landscape-level land use planning and science-based improvements of practices will become increasingly important to ensure sustainable forest product supply chains.

09 BIOMASS FUELS↗

DOE OSTI2017

Discrete and Continuum Plane-Hopper Flow Simulations with Experimental Validation Using X-Ray Imaging, Arch Profilometry and Wall Pressure Measurements

The flow of spherical glass beads, approximately cubic wood crumbles®, and wood microchips are investigated using a combination of discrete element modeling (DEM), finite element analysis (FEA), and physical experiments using a custom plane-flow hopper in which the flow is characterized using x-ray imaging, profilometry to measure arching geometry and pressure measurements at the wall. The purpose of this study is to investigate fundamental flow behavior, and for this purpose the simulations and physical tests are specially designed. During the physical tests and simulations, the hopper geometry begins as a V shape with the two opposing side walls touching at the bottom of the V. Basic tests are performed by first filling the hopper with material, and then rotating the opposing side walls inward about their common intersection axis to cause an approximately uniform stress condition throughout most of the hopper. The side walls then slide upward to effectively increase the size of the opening at the bottom of the hopper until the arch of material in the hopper breaks, and all of the material falls out of the hopper. More advanced tests are also performed in which the initial rotation of the walls is slightly reversed to decrease the pressure in the hopper, corresponding to “preshear” and “shear” conditions in standard shear tests. Shear tests of the materials are also performed using a Schulze automated ring shear tester with a standard size M shear cell, and the shear tests of the glass beads and wood crumbles® are also simulated using DEM to calibrate the DEM with the FEA. Reasonable agreement between predicted and measured flow behavior is obtained indicating that this type of physical tests and modeling shows promise for characterizing and predicting the flow behavior of compressible and anisotropic materials.

09 BIOMASS FUELS↗

DOE OSTI2019

Measured moisture performance of sealed and insulated attics with permeable insulation in california homes

This study performed detailed thermal and moisture measurements in two homes in Fresno and Clovis, California with sealed attics insulated with glass fiber insulation to determine moisture performance in inland California climates. Data were recorded once every minute for more than a year in each home to allow detailed observation of time-varying moisture and thermal conditions. Moisture measurements were taken at multiple locations in each attic and included wood moisture, surface condensation and surface relative humidity. The results showed that there are strong solar-driven diurnal cycles in attic wood and air moisture content, as well as longer-term seasonal and annual variations. Mold growth was obdserved on the North roof deck in one of the two homes even in this sunny dry climate with attics built in compliance with California building codes that specifically address sealed and insulated attics with vapor-permeable insulation. We investigated moisture stratification in the attic and found that, although there is stratification during sunny daytime hours, this was not when wood moisture content, surface humidity or surface condensation are high. Therefore, other moisture transport mechanisms are acting to increase moisture levels near the roof peak. Finally, our measurements also showed that the attic with the highest measured moisture levels did not have any mold growth, while mold was visually observed in the attic whose measurements indicted little or no concern, indicating that the state-of-the-art in moisture measurement and mold growth prediction in building assemblies may be insufficient.

32 ENERGY CONSERVATION, CONSUMPTION, AND UTILIZATI↗

DOE OSTI2021

Measured Moisture Performance of Sealed and Insulated Attics with Permeable Insulation In California Homes

This study performed detailed thermal and moisture measurements in two homes in Fresno and Clovis, California with sealed attics insulated with glass fiber insulation to determine moisture performance in inland California climates. Data were recorded once every minute for more than a year in each home to allow detailed observation of time-varying moisture and thermal conditions. Moisture measurements were taken at multiple locations in each attic and included wood moisture, surface condensation and surface relative humidity. The results showed that there are strong solar-driven diurnal cycles in attic wood and air moisture content, as well as longer-term seasonal and annual variations. Mold growth was obdserved on the North roof deck in one of the two homes even in this sunny dry climate with attics built in compliance with California building codes that specifically address sealed and insulated attics with vapor-permeable insulation. We investigated moisture stratification in the attic and found that, although there is stratification during sunny daytime hours, this was not when wood moisture content, surface humidity or surface condensation are high. Therefore, other moisture transport mechanisms are acting to increase moisture levels near the roof peak. Finally, our measurements also showed that the attic with the highest measured moisture levels did not have any mold growth, while mold was visually observed in the attic whose measurements indicted little or no concern, indicating that the state-of-the-art in moisture measurement and mold growth prediction in building assemblies may be insufficient.

32 ENERGY CONSERVATION, CONSUMPTION, AND UTILIZATI↗

DOE OSTI2023

Techno-economic Analysis of CO2 Capture From Pulp/Paper Plants

This poster presentation evaluates the cost of capturing CO2 from a 400,000 air dried tonne (adt)/year pulp production plant, using Shell’s CANSOLV post-combustion capture process. There are five steps in a pulp/paper process: wood preparation, pulping, chemical recovery, bleaching and papermaking. There are three sources of CO2: combustion of waste wood in the wood-preparation step; combustion of black liquor, a product of pulping; and combustion of natural gas coupled with CO2 generated from calcination of limestone in the lime kiln used in chemical recovery. Standalone (pulp only) and integrated (pulp + paper) mills are modeled. The base case results and sensitivity analyses are displayed.

Mantripragada, Hari↗

DOE OSTI2024

Data Acquisition System Selection and Calibration of Resistive Moisture Content Measurements for Large-Scale Field Studies in Cold Climate Residential Building Envelope Performance

The residential building stock built before the energy codes were enforced has several significant inefficiency problems in terms of insulation and air leakage. To decrease these inefficiencies, building retrofits are necessary. However, if the envelope is not appropriately designed, excessive accumulation of moisture content and thus mold formation and decay inside the envelope layers can be a vital problem. This risk becomes higher, especially in extreme climate conditions such as cold winters and hot and humid summers as in some northern regions of the U.S. Field studies are essential to test the long-term hygrothermal performance of building envelopes. Although in-situ temperature, RH, and heat flux measurements are straightforward, moisture content measurements are cumbersome. Mainly, because of the heterogeneous nature of the wood materials, deviations and nonuniformities within the materials are unavoidable. Resistance measurements are one of the oldest methods used to measure the moisture content of wood and other building materials. In large-scale studies, it is commonly preferred to use multi-purpose data acquisition systems (DAQ) and custom-made or prefabricated moisture pins to measure the electrical resistance (and thus moisture content) of critical building materials. These multi-purpose DAQ systems generally provide lower costs and offer more flexibility. However, these systems require calibration and fine-tuning to achieve accurate moisture content measurements. A large-scale, two-year-long field study was conducted in northern Minnesota to monitor the hygrothermal performance of residential retrofit wall systems in cold climates. Two base case walls and sixteen different wall treatments were tested. Moisture contents were measured at various layers in each wall treatment using 85 sets of moisture pins. This paper focuses on the overall approach, fabrication, and calibration methodology for the combination of custom-made moisture pins and a multi-purpose DAQ. The aim is to directly use the low-excitation multi-purpose DAQ without any extra voltage regulator. A half-bridge circuit is used to measure wood resistance with 4V excitation voltage and 100 kΩ and 500 kΩ reference resistors. The system is calibrated for four different materials: Douglas fir, lodgepole pine, western red cedar, and oriented strand board (OSB). Calibration experiments were done under controlled conditions in 50% and 65% RH test chambers. Resistance-based moisture content calibration curves are obtained for each species. Results show that higher reference resistors provided better calibration curves for lower excitation voltages.

Desjarlais, Andre Omer↗

DOE OSTI2015

X-Ray Radar Imaging Technique Using a 2 Mev Linear Electron Accelerator

X-ray radar imaging, patented in 2013 by James R. Wood, combines standard radar techniques with the penetration power of x-rays to image scenes. Our project strives to demonstrate the technique using a 2 MeV linear electron accelerator (linac) to generate the S-band–modulated x-ray signals. X-ray detectors such as photodiodes and scintillators are used to detect the signals in backscatter and transmission detection schemes. The S-band microstructure is imposed on the variable-width electron pulse, and this modulation carries over to the bremsstrahlung x-rays after the electron beam is incident upon a copper-tungsten alloy target. Using phase/distance calculations and a low-jitter timing system, we expect to detect different object distances by comparing the measured phase differences. The experimental setup, which meets strict jitter requirements, and preliminary experimental results are presented.

43 PARTICLE ACCELERATORS↗

DOE OSTI2016

Physiochemical Characterization of Lignocellulosic Biomass Dissolution by Flowthrough Pretreatment

Comprehensive understanding of biomass solubilization chemistry in aqueous pretreatment such as water-only and dilute acid flowthrough pretreatment is of fundamental importance to achieve the goal of valorizing biomass to fermentable sugars and lignin for biofuels production. In this study, poplar wood was flowthrough pretreated by water-only or 0.05% (w/w) sulfuric acid at different temperatures (220-270 °C), flow rate (25 mL/min), and reaction times (8-90 min), resulting in significant disruption of the lignocellulosic biomass. Ion chromatography (IC), Fourier transform infrared (FTIR) spectroscopy, X-ray diffraction (XRD) analysis, and solid state cross-polarization/magic angle spinning (CP/MAS) 13C nuclear magnetic resonance (NMR) spectroscopy were applied to characterize the pretreated biomass whole slurries in order to reveal depolymerization as well as solubilization mechanism and identify unique dissolution structural features during these pretreatments. Results showed temperature-dependent cellulose decrystallization in flowthrough pretreatment. Crystalline cellulose was completely disrupted, and mostly converted to amorphous cellulose and oligomers by water-only operation at 270 °C for 10 min and by 0.05 wt % H2SO4 flowthrough pretreatment at 220 °C for 12 min. Flowthrough pretreatment with 0.05% (w/w) H2SO4 led to a greater disruption of structures in pretreated poplar at a lower temperature compared to water-only pretreatment.

54 ENVIRONMENTAL SCIENCES↗

DOE OSTI2017

Construction Guide to Next-Generation High-Performance Walls in Climate Zones 3-5 - Part 1: 2x6 Walls

Part 1 of this Construction Guide to High-Performance Walls in Climate Zones 3-5 provides time-proven, practical, and cost-effective strategies for constructing durable, energy-efficient walls. It addresses walls constructed with 2x6 wood frame studs, wood structural panel (WSP) exterior sheathing, and a cladding system installed over WSP sheathing in low-rise residential buildings up to three stories high.

2x6 wood frame studs↗

DOE OSTI2017

Construction Guide to Next-Generation High-Performance Walls in Climate Zones 3-5 - Part 2: 2x4 Walls

Part 2 of this Construction Guide to High-Performance Walls in Climate Zones 3-5 provides straightforward and cost-effective strategies to construct durable, energy-efficient walls. It addresses walls constructed with 2x4 wood frame studs, wood structural panel (WSP) sheathing as wall bracing and added backing for foam sheathing, a layer of rigid foam sheathing insulation up to 1.5 inches thick over the WSP, and a cladding system installed over the foam sheathing in low-rise residential buildings up to three stories high. Walls with 2x6 framing are addressed in Part 1 of the Guide.

2x4 wood frame studs↗

DOE OSTI2017

Construction Guide to Next-Generation High-Performance Walls in Climate Zones 3-5 - Part 1: 2x6 Walls

Part 1 of this Construction Guide to High-Performance Walls in Climate Zones 3-5 provides time-proven, practical, and cost-effective strategies for constructing durable, energy-efficient walls. It addresses walls constructed with 2x6 wood frame studs, wood structural panel (WSP) exterior sheathing, and a cladding system installed over WSP sheathing in low-rise residential buildings up to three stories high.

2x6 wood frame studs↗