Publications associées à Bois

Quantification of Native Lignin Structural Features with Gel-Phase 2D-HSQC0 Reveals Lignin Structural Changes During Extraction

Our ability to study and valorize the lignin fraction of biomass is hampered by the fundamental and still unmet challenge of precisely quantifying native lignin's structural features. Here, we developed a rapid elevated-temperature H-1-C-13 Heteronuclear S ...

Wiley-VCH Verlag GmbH2024

Seasonal variation in the xylem sap composition of six Australian trees and shrubs

Alice Jacqueline Frédérique Gauthey

In recent years, xylem sap composition has been shown to affect xylem hydraulics. However, information on how much xylem sap composition can vary across seasons and specifically under drought stress is still limited. We measured xylem sap chemical composit ...

Oxford Univ Press2023

Selecting Suitable Near-Native Lignins for Research

Jeremy Luterbacher

There are several methods to isolate near-native lignins, including milled-wood lignin, enzymatic lignin, cellulolytic enzyme lignin, and enzymatic mild-acidolysis lignin. Which one is the most representative of the native lignin? Herein, near-native ligni ...

Amer Chemical Soc2023

Direct conversion of lignin to functionalized diaryl ethers via oxidative cross-coupling

Paul Joseph Dyson, Mingyang Liu

Efficient valorization of lignin, a sustainable source of functionalized aromatic products, would reduce dependence on fossil-derived feedstocks. Oxidative depolymerization is frequently applied to lignin to generate phenolic mono- mers. However, due to th ...

Nature Research2023

Cockroach: an open-source tool for point cloud processing in cad

Yves Weinand, Julien Gamerro, Andrea Settimi, Petras Vestartas

In the architecture, engineering and construction (AEC) sector, the use of point cloud data is not a novelty. Usually employed to retrieve data for inspecting construction sites or retrofitting pre-existing buildings, sensors like LiDAR cameras have been k ...

Association for Computer-Aided Architectural Design Research in Asia (CAADRIA)2022

Robotically-Fabricated Nexorades from Whole Timber

Yves Weinand, Aryan Rezaei Rad, Petras Vestartas

This paper introduces the conceptual design of sustainable timber structures using raw wood. It pre-sents a workflow for systematically generating Nexorades using a tiling method for multi-valence quad subdivided surfaces. The system is designed based on a ...

2021

Mechanical properties of a balsa wood veneer structural sandwich core material

Thomas Keller, Anastasios Vassilopoulos, Niloufar Vahedi

Balsa wood is an appropriate core material for structural sandwich applications due to its high strength- and stiffness-to-weight ratios. However, the mechanical properties vary considerably owing to the inherent scattering of natural wood materials. One a ...

2020

Thermomechanical characterization of a balsa-wood-veneer structural sandwich core material at elevated temperatures

Thomas Keller, Anastasios Vassilopoulos, Chao Wu, Niloufar Vahedi

The tensile, compressive and shear behavior of standardized specimens cut from a veneered balsa wood used as structural sandwich core was investigated at ambient temperatures of up to 250 degrees C. The average moisture content was 9.1%. The specimens' res ...

ELSEVIER SCI LTD2020

Mechanical properties of natural fiber composites produced using dynamic sheet former

Composites formed from wood fibers and man-made cellulosic fibers in PLA (polylactic acid) matrix, manufactured using sheet forming technique and hot pressing, are studied. The composites have very low density (due to high porosity) and rather good elastic ...

2020

Statistical accuracy for estimations of large wood blockage in a reservoir environment

Anton Schleiss, Michael Pfister, Paloma Furlan, José Pedro Gamito de Saldanha Calado Matos

The blockage of weirs or bridges by in-stream wood can reduce the flood discharge capacity, leading to hazardous situations. To assess the related risk, blocking probabilities quantifications are needed. However, large wood has a random behaviour and it is ...

SPRINGER2020

Experimental investigation of mesoscale variability of clear spruce mechanical properties in the radial direction

Thomas Keller, Anastasios Vassilopoulos, Alireza Farajzadeh Moshtaghin, Steffen Franke

The aim of this work is the investigation of mesoscale/local variability in mechanical properties of clear timber in the radial direction. Clear Norway spruce wood, Picea abies, was used for cutting specimens of different lengths with a small cross-section ...

2020

Topology of Pretreated Wood Fibers Using Dynamic Nuclear Polarization

David Lyndon Emsley, Jeremy Luterbacher, Arthur César Pinon, Pierrick Berruyer, Jasmine Viger-Gravel, Wu Lan, Michel Bardet

In the continuously developing field of lignocellulosic biomass, high-yield lignin depolymerization processes are sought to optimize its productivity and profitability. Recently, formaldehyde stabilization during lignin extraction and biomass pretreatment ...

2019

Modelling Workflow for Segmented Timber Shells using Wood-wood Connections

Yves Weinand, Julien Gamerro, Nicolas Henry Pierre Louis Rogeau, Petras Vestartas

This paper presents a modelling method based on planarization for double-curved segmented timber shell made from quad polygons and assembled by wood-wood connections. The inspiration is taken from timber dome structures, where solid timber walls were built ...

Springer2019

Blocking probability of large wood and resulting head increase at ogee crest spillways

Paloma Furlan

Large wood increases the hydraulic complexity of rivers, yet it may block and modify the flood discharge capacity of hydraulic structures such as bridges and spillways. When spillway blockage occurs, dangerous and hazardous situations have been observed at ...

EPFL2019

Protection Group Effects During α,γ-Diol Lignin Stabilization Promote High-Selectivity Monomer Production

Jeremy Luterbacher, Wu Lan, Masoud Talebi Amiri, Christopher Marc Hunston

Protection groups were introduced during biomass pretreatment to stabilize lignin's α,γ-diol group during its extraction and prevent its condensation. Acetaldehyde and propionaldehyde stabilized the α,γ-diol without any aromatic ring alkylation, which sign ...

Wiley-VCH Verlag GmbH2018

Rotational mechanical behaviour of wood-wood connections with application to double-layered folded timber-plate structure

Yves Weinand, Julien Gamerro, Christopher Werner Matthias Robeller

This paper is focused on the structural design of an innovative wood-wood connection designed for a full-scale double-layered timber folded-plate structure: the new Vidy theatre pavilion (Lausanne, Switzerland). Investigations into the potential of these n ...

2018

Photoluminescent, upconversion luminescent and nonlinear optical metal-organic frameworks: From fundamental photophysics to potential applications

Fatmah Ebrahim, Kyriakos Stylianou, Ngoc Tú Nguyên

Metal-organic frameworks (MOFs) are a class of porous materials prepared by the self-assembly of metal ions or clusters with organic ligands. The unique characteristics of MOFs, including structural tunability, high surface areas, low densities and tailore ...

2018

Spillway blockage caused by large wood in reservoirs

Anton Schleiss, Michael Pfister, José Pedro Gamito de Saldanha Calado Matos, Paloma Furlan

Large wood (LW) elements are often transported by rivers into reservoirs during heavy rainfall events. Large wood has important environmental attributes that benefit the diversification of riverine ecosystems. There are several studies dealing with the tra ...

E3S Web of Conferences2018

Semi-Rigid Moment-Resisting Behavior of Multiple Tab-and-Slot Joint for Freeform Timber Plate Structures

Stéphane Nicolas Roche

Historically based on the transfer of ancestral know-how, the art of carpentry changed considerably at the beginning of the 21st century with the arrival on the market of engineered wood products (EWP) and computer numerically controlled machines (CNC). Th ...

EPFL2017

Spruce tree-ring proxy signals during cold and warm periods

The strength and temporal rigidity of climate signals are important characteristics of proxy data used to reconstruct climate variability over pre-instrumental periods. Here, we assess the performance of different tree-ring proxies, including ring width, m ...

Bogucki Wydawnictwo Naukowe2017