Wood Science - Science topic

Dear @Goran Schmidt,

I am looking for a bamboo machinery if you could help with this regards.

Looking forward to hearing from you,

Layth

Sauradipta Ganguly

@ Sauradipta Ganguly

Hi, thanks for the answer and your valuable suggestion. Yeah I guess so. A balance between the added cost and performance increases is important. The flammability of wood materials is the primary problem in the application of timber structure, especially in high-rise buildings. Experimenal studies will be carried out in the futural work.

This may interest some of you:

Ruffinatto, F., Crivellaro, A. (2019). "Atlas of Macroscopic Wood Identication". Cham: Springer.

Looking for the work of Mauritius Escher a Dutch graphic artist, he can take you into the realm of patterns, woodcutting or even the construction of wooden figures that fit together.

Yes I am working with bamboo charcoal. Please help me .

I think using the strain and force measurement methods to calculate it with the definition of the mechanical properties is a good way to find.

The next Xylem International meeting will most likely be organized by the University of Padova in Italy i September/October 2019. We are finalizing the organisation right now and I will let you know when I know more.

And yes, Cavitation will be "la part du lion" in this meeting!

Hervé

As a rule I'd say this is the case, yes. So it doesn't substitute sawnwood, but rather increases the demand for it. It's a question of moving downstream in the value chain.

Not sure if one should somehow differentiate here between integrated facilities where the intermediate product is an integral part of the process and CLT mills that purchase sawnwood from elsewhere (if such facilities exist). Also, it may be possible to use lower diameter logs and lower quality logs in the CLT production process, so the RWE may be also smaller than presented above.

I tried Pinosylvin and Pinosylvin-Monomethylether. Fast blue B salt lead to a fast and intensive red staining of Pinosylvin but not of Pinosylvin-Monomethylether. Both substances show an intense flurorescence when illuminated with UV 365 nm. Obviously the heartwood detection and the fluorescence and the staining of coatings over the heartwood of Pinus sylvestris with Fast Blue B salt is caused by Pinosylvin. 

Google "raman wood"

You can find attached file for some information.

Hope this will help.

Regards,

given the diversity of eucalyptus species (about 600 species, grown from tropical environments to semi-arid ones), with very variable growth rates and wood structures, the values above from Larry Baxter are as precise as one is going to get. If you have know the species you are interested, it might be possible to find some more precisse values.

Dear Binoy Kurian,

The characterization of wood is usually performed through the physical, mechanical, chemical and anatomical. Furthermore, there are destructive and non-destructive methods for the characterization of wood.

I send you some journals where you can easily find these characterizations.

I hope I understood your question and helped you.

Best Regards!

Mugilan Muthumanikam

Plz discuss with Dr PC Sarkar and Dr MF Ansari ,ICAR-IINRG Ranchi.............They are doing on this aspect...........................decomposition process............

yes

JK PAPER ALSO USED SUBABUL WOOD AND DOING 5000 HA PLANTATION EVERY YEAR FROM 2010 TI TILL DATE.

Hi,

I also recommend CooRecorder and basically any flatbed scanner (higher resolution is better). It is worth mentioning that actually you are buying packed of softwares from Cybis. It is called Cdendro and includes two programs: CooRecorder, which is dedicated to measure ring widths and also other parameters and CDendro which is tool to test the quality of measurements, crossdate and build chronology.  It is easier to work using this couple of programs because the file formats is identical. I recommend using Cofecha, which is great tool or/and dplR only as a next step.

Good luck and don't hesitate to ask about details if necessary!

Dear fellow:

It depends upon the kind of WPC. Is it polymer reinforcing wood, or wood reinforcing polymer?

I have attached one of the easiest literature I have ever read about the "polymer reinforcing wood"  topic.

regards

Not sure if this can help you, maybe worth checking.

Hello! Due to the high temperatures in the wood processing hemicellulose (wood sugar) decomposes. Low equilibrium moisture content. This eliminates the conditions for the emergence and propagation of fungus and microorganisms.

Thanks Mr. Pavel, you already gave me some fresh ideas :) I thought about hardness, but not others, I will have a look to them :)

Thank you very much for your answer, Adha. You understood correctly that I'd like to produce them from lamella. Its julvenile wood of young tree mechanical properties is in the lower tier of tropical hardwood, contains many knots, and has high shrinking/swelling (>20% by volume). I'm not sure that if those kind of product will improve the wood mechanical properties for construction use.

By the way, thanks again for your suggestion about the glue issue.

treating the raw lignin with sulphuric acid solution (1 wt%) for

1 h, in a proportion of 20 mL of solution per gram of sample, followed

by washing extensively with deionized water until neutral

pH in washing water was attained.

They are average values of triplicate

determinations, where the standard error did not exceed 5%.

Dear Samantha

For tangential and radial sections it is also not possible for us to get big areas with clean breaks. Only for small areas you get plane surfaces (see figure). I guess the problem is that the crack doesn't follow the fibre direction after thermal degradation of the cell wall.

Michael

Dear Miguel,

A good approximation of the chemical composition of wood, regardless of the species, is: 50% carbon, 44% oxygen and 6% hydrogen. Therefore, to make an example, 1 kg of wood (at the oven-dry state) stores approx. 0.5 kg of carbon.

As for the comment of Suresh, the density of wood varies with the species and counts to calculate the carbon stored, of course it depends if you consider weight or volume. Referring to the above example, 1 kg of wood always stores 0.5 kg of carbon, but occupies different volumes depending on its density. To say this with a more analytical example:

1 kg of wood with oven dry density of 400 kg/m3 = 0.025 m3 = 0.5 kg of carbon

1 kg of wood with oven dry density of 500 kg/m3 = 0.020 m3 = 0.5 kg of carbon

@Martin Baeker ，the slipe of Elastic deformation is also bigger than test, you can see it in picture

Please go through these PDF attachments also.

Hi,  you can fiind all the data you need in the text Wood Handbook - Wood as an Engineering Material,

or

particularly in the chapters 4-2 (MOE), 4-3 (MOR), and 10 (different kinds of wood panel). 

Best regards.

Togni

After wood processing, sawdust is thrown on the ground?

hi,

This paper looks to answer that question mr. Görgün :

Antikainen, J., Hirvonen, T., Kinnunen,J.,and Hauta-Kasari, M. 2012. Heartwood detection for Scotch pine by fluorescence image analysis. Holzforschung 66: 877–881.

Dear Suresh,

Thank you for your answer.

I'll try to figure it out on those website.

Hi Suresh,

I frequently use fluorescene in failure Analysis of Wood and Wood based materials (see the file attached). A more scientific approach can be found in this publication: https://www.researchgate.net/publication/275969083

Cheers

Dirk

Several factors influence the durability of the interior parts of standing stems. The presence of heartwood extractives that are toxic for wood destroying fungi is only one aspect. If this was the only answer we would never find a hollow black locust (Robinia) and for example beech would always be severely attacked by fungi already in the standing tree.  In reality the durable heartwood of black locust is often attacked by fungi  whereas the absolutely non-durable beechwood is attacked less often (I am only talking about the standing tree – after felling the situation is completely different). The ability of the different trees to prevent the ingress of fungi into the interior is as least as important as the durability of the wood. In the case of willow it might even be speculated that being hollow and therefore collapsing rather young might be an advantage. Willow is often distributed by vegetative propagation. Maybe the early collapse increases the chance for a better propagation.

Maybe the article of Shigo (see link below) is helpful:

Hi Edwin,

Thanks for your response. It helped me to deduce an approximate value of cellulose and lignin which lies in the similar region of published values. Though, I am unable to make a distinction in amount of hemi-cellulose present. Could you please provide me a journal paper(s) which has discuss this methodology in detail?

Thanks.

rw

As both mentoned methos are based on  alkaline conditions of pulping, I gues the sulphite method will be more effective from viewpoint of raw material delignification.  Tremperature of this process can be higher as compared with that using NaOH/H2O2 and thus time of delignification shorter. Disadvantage of alkaline sulphite pulping is its higher negative environmental impact.

The mechanical properties of  both /peroxide and sulphite/ pulps prepared under identical conditions may be almost the same.

Hi,

you can use the single fiber tensile test to determine the mechanical properties of fibers using the single filament tensile tests procedure described in ASTM D-3322-01 standard test method.

Regards,

BELOUADAH Zouheyr

Dear Attila,

I think it will be helpful to define your question a little bit. Do you mean rot types (as white and brown), or classes of decay, or something else? This can help to get a useful answer. For some approaches in the field of wood decay you can see a paper in attachment. And it may be helpful to address Dmitry Schigel https://www.researchgate.net/profile/Dmitry_Schigel for wood-decay study approaches.

Best wishes,

Elena

be careful with advise by Florian Rebstock - the model proposed in this paper is not so easy to use. I have got some problems with coefficients.

You can take specific cutting resistance for pine wood from the Figure 8c in my paper (open access) - it is for dry wood. Feed speed along wood fiber.

Thank you for providing me with these. They are interesting texts. However, I am specifically looking for the use of wood in preparing animal skins whereby a wooden tool is made to prepare the hide for producing clothing or other items. The reason I am looking for this is because at a site where we suspect intense hide-working to have taken place we are instead finding evidence for wood-working and someone asked whether wood was used in hide preparations

There is no absolute method of cellulose isolation, as it is connected to other structural compounds of wood, i.e. lignin and hemicelluloses. If you choose mild conditions, resulting cellulose will contain significant amount of them. On the other hand, strong delignifying agents will dissolve some cellulose as well. The most popular methods of cellulose determination (in the order of increasing strength of reagents and decreasing yield) are following:

In all cases wood should be extracted (with ethanol-benzene mixture, for example) prior to cellulose isolation. For school project the second method will be probably the most suitable. Extracted wood chips have to be refluxed in ethanol-HNO₃ mixture for an hour, filtered on porous-glass funnel and the steps repeated total 3-4 times (conifers need more cycles). After delignification the sample should to be carefully washed with water and boiled twice in pure water to completely remove residue nitric acid. If you fail to find a detailed procedure, send me a message, and I'll try to help you.

Regards

Not a model but a case study.  

Decay and termite resistance, water absorption and swelling of thermally compressed wood panels

This paper gives some ideas that a model would depend on the type of modification to the wood.

CHEMICAL MODIFICATION:

A NON-TOXIC APPROACH TO WOOD PRESERVATION

  To calculate stem volume knowing basal diameter and length, you have to make an assumption about taper. In trees, the clear trunk excluding the root flare often tapers as a parabaloid (to calculate which you'd need either top diameter as well as basal diameter, or diameter at the mid-point), while the top part of the tree, within the crown, often tapers as a cone..

  If you have only one diameter measurement you also have to assume that the cross-section of your seedling stems is circular, which may not be strictly correct, and you may also be most interested in stem volume in relation to some other variable (leaf area, growth rate etc).

  It might be best to accept that you can calculate an index of stem volume, rather than actual stem volume. In that case the index would probably be equally informative whatever you assume about taper and cross-sectional shape.

Thank you for your help Maria Cristina and Cyrill Heitner. 

Nathan,

I am not too familiar with coppicing and pollarding. What I see is farming, where fast growth species such as popular (Populus sp.) or maple (Acer sp.) are grown to ~25 cm and then harvested for firewood. With staggered planting, the supply is constant. I suppose with coppicing and pollarding you would not necessarily have to worry about distinguishing between young growth trees and limbs, since young trees would be uncommon?

See papers of Stanzl-Tschegg S., Frühmann K., Tan et al., Burgert, etc. in the years 1986 - ca. 2005. If you do not find them let me know. My mail-address: stefanie.tschegg@boku.ac.at.

Are you looking for current wood consumption patterns or historic wood consumption patterns. 

As to people study this, well there are a number of reasons not least being the maintenance or management of a resource.

Briefly, it is used to measure the active surface area. The more iodine that is adsorbed on the surface, the higher the iodine number and - in theory - the better the activated carbon will be as an adsorbent material.

There is already an answered question, with more detailed answers and info - https://www.researchgate.net/post/What_is_iodine_number_in_terms_of_activated_carbon_What_is_the_significance_of_iodine_number_How_to_find_it

Please see the paper of non-destructive techniques measuring stiffness on pinus radiata seedlings. This might be useful for your research. 

@Mehdi Yasaee , Thanks very much.

Please go through the following research article and the attachments for the answer:

Dear Antoine, your question is not particularly specified. What do you understand by quality? But the linked FAO dokument "Chapter 8. Quality control of charcoal and by-products" gives some information concerning quality control of charcoal.There are several ASTM standards cited, I thinks this will give you some hints.

Best regards

YES.

THIS IS A PROBLEM FACED DURING HARVESTING AND STORAGE OF LOGS SPECIFICALLY FOR THE PINE SPECIES OR OTHER SOFT WOOD SPECIES.

IT MAY HAPPEN BECAUSE OF EXCESSIVE LOSS OF MOISTURE FROM THE CROSS SECTIONAL AREA AND THUS DEVELOPMENT OF INTERNAL STRESSES.

ONE SOLUTION IS APPLICATION OF BITUMINOUS PAINT IMMEDIATELY AFTER HARVESTING ON THE CUT SURFACES.  

This is related to the properties of the heartwood. The conductive properties of cell are shot down by filling the lumens by varies chemicals. As long as it is not rotten this makes wood almost impossible to penetrate by water. The decay process is slower down by lack of oxygen since the wood is submerge.

Hi Nguyen, we remove the PEG 2000 by a few min storage in ethanol followed by a few minutes in  water. Dirk

I don't know in India but in France there is one which produces board with recycled paper as raw material.

You can use the suggestion of Downes et al. (1997). In this book, Downes suggest assess the variation radial and longitudinal in level of annual ring of trees growth. This book inform about the variation pattern of wood properties in special for paper and cellulose production.

thanks alot @Rafik

I have one value perpendicular to the grain from "A Heat Transfer Textbook," by Lienhard and Lienhard.

As I said before, shrinkage takes place with diminishing moisture content, as a consequence of the increase of cellulose internal bonds. When submitted to moisture, it can not regain the same degree of humidity, since water do not have sufficient energy to broke cellulose-cellulose bonds. The other components of wood do not suffer significant changes.

That is the answer to your question. May be you have to put it in another way if it is not what you want to know...

Its a very good question. Let me see if i can help you.

The shrinkage is not homogeneous. While the disk surface, due the contact with the external environmental, reach faster to below of the saturation point, the inner part still is near of the maximum moisture content. Due this delta, the surface shrinks while the middle not, starting the split in the weaker point of the tissue: rays parenchyma cells (if you have boundaries parenchyma type like jatobá, mahogany, etc. the split could be in that way).

The wood tissue have an great resistance to compression, flexion, and another others... but we can not say the same to split. In this way, the open newly surface by the split start to shrink in a different compass of the middle, generating an deeper split, occurring that again and again until we have an big crack.

Thanks  you. 

I think that use some numerical model to get some optimal parameters before performing an experiment if possible.

Comsol might help you to save time and resources.

Dear Edwin, I recommend you use NREL procedures.

Best regards

Frantisek

CuO Oxidation in NaOH and liquid liquid extraction with ethyl acetate.  Derivatize with BSTFA before GC/MS analysis. 

The attached 1982 paper is the original method.  The 1992 paper highlights a number of additional lignin products that can be obtained with this method, which may help you to identify products of lignin degradation.  I also put up a link to my website which has a lot of distilled information about the method, equipment, compounds, data analysis etc.

Lignin a complex polymer can be estimated as as Klason's acid insoluble lignin as described by Effland, 1977. The brief procedure is:

The wood or straw sample is dried at 80 degree Celsius in an oven. The dried straw containing the any biomass was thoroughly crushed in a pestle and mortar. This straw was again dried at 80oC and 200mg of it was taken in a wide mouth test tube (2cm diameter). To this sample, 3ml of 72% H2SO4 (v/v) was added to each tube and the tubes containing the sample were placed in a water bath preset at 30 Celsius for primary digestion of straw. The contents were continuously stirred with glass rod and after 1 hour, transferred to a flask. The volume was made upto 84ml with distilled water and the flasks containing residual samples were autoclaved at 10psi for one hour. The warm digest was then filtered via preweighed sintered glass crucible (or whatmann filter paper no 1). The crucible containing the acid insoluble lignin was washed with distilled water to remove acid from it. The same procedure was adopted for undegraded wheat straw controls. Capability of selective lignin degradation was ascertained by comparing the extent of loss in TOM with that of lignin loss. Percent lignin loss is based on the difference in amount of lignin in the uninoculated blank and the inoculated substrate.

You can follow the NREL standard protocol to determine the biomass composition (lignin, cellulose, and hemicellulose)

I agree with the very good answers that were already given. I will add that Glulam can be prepared so that it can bend and have architectural aesthetics as well as structural performance. 

Our work found that the species of wood mattered most in relation to adhesive properties.  Ensuring that your bonding methods are solid, everything else should work.  I think this is an area that has yet to be explored.  Good luck.

If you do not have any protocol for bamboo, I suppose the you can use the same parameters as we use for polping wood. For 1 kg of dry wood (or bamboo), apply 100 g of Soda, 40 g of Sodium sulfide and complete with water the 4 liters of cooking liquor. Soda and Sodium sulfide and high temperature (160-170°C max) during 2,5 to 4 hours should works well. 

Please find the attached file here. Hope it may help you.

Regard

Sandeep Kumar

Hallo!

Dear Uthappa,

Other possibility is to apply micro-drilling technique, according the force during the drill it will be possible to estimate the density......Just check the micro-drilling....

Best regards

Vladi

Dear Doctor Shaban and Sunil

thank you for your oncern and valuable papers.

My results showed that the production of  tension wood starts immediately (within a few days) after bending stress.Trees  produce only sufficient amount of TW, till their straightness is recovered.

If bending  was continued thus the new straight growth would be in normal direction and TW production due to bending would stop.

This is not to forget the internal stresses of trees which lead to produce reaction wood even in straight trees. Some Genus are more susceptible like: Poplars and Eucalypts.

Dear Pierre,

The status of prEN16351 "Timber structures - Cross laminated timber - Regulations" is still "under approval" (Committee CEN/TC 124). However, I know, that the approval process is being finalized. Maybe one of member of COST Action FP1402 could tell you more details (http://www.cost.eu/COST_Actions/fps/Actions/FP1402?management).

Best regards

Paweł

Some findings are in:

Kraszkiewicz A. 2009. Analysis of selected chemical properties of black locust (Robinia pseudoacacia L.) wood and bark. Inzynieria Rolnicza. Nr 8 (117). s. 69-75

The content of sulfur in wood and the bark of trunks ( author 's own results)

The sulfur content in the wood trunks ranged from 0.02 to 0.11 g⋅kg -1 dm On average , the content

sulfur in the wood trunks was 0.06 g⋅kg - 1 S. M. The sulfur content in the bark of trunks was

1,10-1,80 g⋅kg - 1 S.M. (approximately 1.48 g⋅kg - 1 S.M. ) . It should be noted that the sulfur content

in the cortex was on average 37 times higher than in the wood.

All stands were considered equal age (35 - years) and were grown in similar

habitat conditions on the same piece of soil - sand and at

insufficient abundance of land in nutrients. differentiating factor

So it was an exhibition of the slope (N , SE and S) and the position stand on its slope

(top or bottom ) .

Tested black locust wood trunks in the dry state contained an average coal -

51.5 % ; Hydrogen - 5.8% ; 42.1% oxygen ; nitrogen - 0.05% ; Sulphur - 0.006 %. While the bark of stems:

carbon - 51.1% ; Hydrogen - 5.8% ; 35.7 % oxygen ; Nitrogen - 2.48 % ; Sulphur - 0.148 %.

The literature [ Antkowiak 1997; Demirbaş 2004 ; Mushroom 2004 ; Prosinski , 1984; fisherman

2006 ] states that the wood without bark contains carbon - 48-52 % ; Hydrogen - 6.2-6.4 % ; oxygen

38-42 % ; Nitrogen - 0.1-0.5 % ; sulfur - <0.05 %, while the bark comprising: carbon - 48-52 % ;

Hydrogen - 4,6-6,8 % ; 24,3-42,4 % oxygen ; Nitrogen - 0.3-0.8 % ; sulfur - <0.05 %.

Identified during the study of carbon , hydrogen, oxygen , nitrogen and sulfur in the wood

and carbon, hydrogen and oxygen in the cortex of black locust were comparable to the contents

these elements administered to other species of trees. Only the amounts of nitrogen and sulfur

robiniowej cortex were about three times higher than the upper ranges of content

of these elements in the bark of other species of trees.

Black locust bark contains much more sulfur and nitrogen than wood . these elements

in the combustion process are responsible for the formation of environmentally hazardous

the exhaust gas (NOx , N2O , SO2 and SO3 ) [ Dzurenda 2004 ; Fisherman 2006 ] , which , inter alia, contributes

the depreciation of the raw material in terms of its energy use .

Hi Pierre,

Thanks for the reference, very interesting study, and similar to small tests we've done on freshly felled burnt timber.

An unanswered question for me is still the effect on timber recovery from burnt trees that recovered after the fire. Abnormal growth or resin inclusion following after fire damage might lead to lower recovery of structural timber from these logs.

I believe that the plant and therefore wood is an unique biomaterial. The increase on the world population is a key factor for everything. The world population will reach near to 9.85 billion in 2050. Thatswhy urbanization, health and energy will be the new directions. Wood and wood science will find suitable places in these areas. I can suggest following topics:

1- Cheap and modular wooden constructions for disaster effected regions (earthquake, storm, flood etc)

2- Wood and wooden products or bacterial cellulose related small production possibilities for underdevoloped countries, people and refugees.

3- I see also and direction in biomimetic of plant-wood and a philosophic aproach according to wooden structure.