scholarly journals Wood characterization of Tectona grandis L. F. cultivated in Brazil: a review of the last 30 years

2021 ◽  
Vol 10 (14) ◽  
pp. e162101421549
Author(s):  
Israel Luiz de Lima ◽  
Maurício Ranzini ◽  
Eduardo Luiz Longui ◽  
Juraci de Andrade Barbosa
Keyword(s):  
Genetic Material ◽  
Tectona Grandis ◽  
Technological Properties ◽  
Research Programs ◽  
Teak Wood

Worldwide, Tectona grandis (teak) is recognized for its productivity and the quality of its wood. The Brazilian market is already seen as a great potential for consumption and production of teak wood. Therefore, the objective of this work was to characterize the teak wood grown in Brazil through a bibliographic survey of the results already available. In general, it was found that the teak wood planted in Brazil has a certain variability in its technological properties, and these variations are due to the origin, genetic material, age, planting location and the cycle used in the management of the forest. In a way, we still do not have much research on the quality of teak wood, and it would be important to implement research programs and experiments that consider the different genetic materials, growing environments, planting spacing, silvicultural tracts and ages of cutting, to allow greater knowledge about the growth and the factors that can influence the quality of the wood to be produced.

scholarly journals SURFACE CHEMICAL AND COLOR CHARACTERIZATION OF JUVENILE TECTONA GRANDIS WOOD SUBJECTED TO STEAM-DRYING TREATMENTS

2016 ◽  
Vol 23 (01) ◽  
pp. 1550091 ◽  
Author(s):  
ALEXANDER BERROCAL ◽  
RÓGER MOYA ◽  
MARÍA RODRIGUEZ-SOLIS ◽  
RICARDO STARBIRD ◽  
FREDDY MUÑOZ
Keyword(s):  
Color Change ◽  
Tectona Grandis ◽  
Surface Chemical ◽  
Surface Color ◽  
Teak Wood ◽  
Text Color ◽  
The Fourier Transform ◽  
Moisture Conditions ◽  
Steam Drying

The color of Tectona grandis wood is an attribute that favors its commercialization, however, wood color from fast-growth plantation trees is clear and lacks uniformity. The aim of this work is to characterize steamed teak wood by means of the Fourier transform infrared spectroscopy (FTIR) and [Formula: see text] color systems. Two moisture conditions (green and 50%) and two grain patterns (flat and quarter) of boards were analyzed through the application of different steaming times (0, 3, 6, 9, 12, 15 and 18[Formula: see text]h). The FTIR results showed that the bands at 1158, 1231, 1373 and 1419[Formula: see text]cm[Formula: see text] did not show any change with steaming, whereas the bands at 1053, 1108, 1453, 1506, 1536, 1558, 1595, 1652, 1683, 1700 and 1733[Formula: see text]cm[Formula: see text] presented a decrease in the intensity with the steaming time. The band at 1318[Formula: see text]cm[Formula: see text] was the only one that increased. Lightness ([Formula: see text]) was the most affected parameter, followed by yellowness ([Formula: see text]), while redness ([Formula: see text]) showed the smallest change. Surface color change ([Formula: see text]) presented the lowest value between 3[Formula: see text]h and 6[Formula: see text]h of steam-drying in the boards with flat grain, whereas for boards with quarter grain, the smallest [Formula: see text] value was obtained after 18[Formula: see text]h of steaming.

Effects of Wood Modification Using Natural Resin on Wood Quality and Bonding Properties

2020 ◽  
Vol 10 (2) ◽  
pp. 48-52
Author(s):  
Muhammad Navis Rofii ◽  
Ragil Widyorini ◽  
Ganis Lukmandaru
Keyword(s):  
Dimensional Stability ◽  
Wood Quality ◽  
Tectona Grandis ◽  
Wood Modification ◽  
Natural Resin ◽  
Gum Rosin ◽  
Bonding Properties ◽  
Teak Wood ◽  
Petroleum Oil

The aim of this study was to investigate the effect of gum rosin impregnation upon a low quality young teak wood in order to enhance its quality. The main objective of the treatment was to enhance the dimensional stability, as well as strength and to reduce the hygroscopicity. A 15-years old thinned teak wood (Tectona grandis L.f.) and gum rosin from Pinus merkusii Jungh. et de Vries were used for wood modification treatment by impregnation. Three kinds of non-polar solvents, i.e. turpentine oil, petroleum oil and n-hexane-, were used to make gum rosin solution. The results indicated that gum rosin impregnation did not markedly enhance the quality of young teak wood in terms of either dimensional stability or hygroscopicity; however, a little enhancement was delivered by using 15% gum rosin solution with n-hexane as the solvent. The treatment with petroleum oil solvent (at concentration of 7.5%) and at 15% concentration with n-hexane solvent resulted in highest bending properties. The highest bonding strength in dry condition was resulted by treatment with turpentine oil solvent.

An investigation of selected properties of teak wood from 9-year-old plantation forest in Indonesia

2020 ◽  
Vol 110 ◽  
pp. 61-72 ◽  
Author(s):  
Muhammad Effsal Hadinata ◽  
Paweł Kozakiewicz
Keyword(s):  
Tectona Grandis ◽  
Complete Information ◽  
Acoustic Properties ◽  
Plantation Forest ◽  
Short Rotation ◽  
Teak Wood ◽  
Wood Demand ◽  
Increasing Demand ◽  
Tectona Grandis L.F

An investigation of selected properties of teak wood from 9-year-old plantation in Indonesia. Teak (Tectona grandis L.f) listed in standard EN 13556:2003 (code TEGR) is known as the most popular species in tropical countries, especially in Indonesia. It has not only good qualities in physical properties and mechanical properties, but it also has an aesthetics pattern. The best teak wood is usually more than 80 years old. It is too long a period of time and cannot fulfil the current wood demand. To fulfil the increasing demand, researchers in Indonesia have developed short rotation teak wood. However, the quality of this wood is rather low. The objectives of this study were to obtain complete information about mechanical, physical and acoustic properties of 9-year-old teak wood, to compare its properties with conventional teak wood and to evaluate the optimal utilization of 9 years-old teak wood based on its properties.

Characterization of a Clay Body Used for Red Ceramics in São Sebastião, District of Campos dos Goytacazes, State of Rio de Janeiro, Brazil

2015 ◽  
Vol 820 ◽  
pp. 8-12 ◽  
Author(s):  
Afonso Rangel Garcez de Azevedo ◽  
Jonas Alexandre ◽  
Euzébio Barnabé Zanelato ◽  
Rafael Picanço Oliveira ◽  
Rodolfo Cretton de Souza ◽  
...  
Keyword(s):  
Rio De Janeiro ◽  
Northern Region ◽  
Chemical Characteristics ◽  
Technological Properties ◽  
Clay Deposits ◽  
Clay Body ◽  
Physical And Chemical ◽  
Red Ceramics

The municipal area of Campos dos Goytacazes in the northern region of the state of Rio de Janeiro, Brazil, is the state’s major industrial pole for red ceramic fabrication. The extensive clay deposits and easy to mine conditions have attracted more than one hundred ceramic industries to operate in the area. In particular, the district of São Sebastião contributes to the production of red bricks and tiles but the characterization of the existing clay and the quality of ceramic pieces has not yet been evaluated. Therefore the present work carried out an investigation of a typical clay body used in São Sebastião by means of its physical and chemical characteristics. The technological properties of red ceramics fabricated from this clay body and fired at temperatures of 700, 850 and 1100oC indicate that they comply with the mechanical strength requirements for masonry bricks. However water absorption is not satisfactory due to the excess of sand and lack of fluxing elements.

scholarly journals The Effect of Storage Periods of Teak (Tectona grandis) Bud in the Sheath of Banana to the Succesfulness of Budding

2018 ◽  
Vol 6 (1) ◽  
pp. 50
Author(s):  
Sari Pangastuti ◽  
Afif Bintoro ◽  
Duyat Duryat
Keyword(s):  
Economic Value ◽  
Tectona Grandis ◽  
Key Word ◽  
Cultivation Technique ◽  
Teak Wood ◽  
Number Of Leaves ◽  
Propagation Technique ◽  
Level Of Significance ◽  
Cultivation Techniques

 Teak (Tectona grandis) is one of comercial plant which has good quality of wood and has high economic value. The enhancement and improvement of teak cultivation techniques was need to be done to fulfill the demands of teak wood. Budding was one of cultivation technique that combine the generative and vegetative propagation technique, so that the benefits of both technique could be obtained at once. The obstacles of budding technique were about the buds storage and distribution. The aim of the experiment were to determine the effectiveness of banana sheath in maintain the viability of teak buds and to determine the maximum periods of teak buds storage. A randomized completely block was employed as an experiment design with two groups and four treatments. The first group was the storage out of banana sheath bag, and the second group was the storage inside of with banana sheath bag. Four periods of storage were used as treatment consist of 0 day of storage (Y0), 2 days of storage (Y1), 4 days of storage (Y2), and 6 days of storage (Y3). Data were analyzed using ANOVA with further testing using LSD on the level of significance 5%. The result showed that the storage of teak buds inside the banana sheath bag and stored up to six days were be able to maintain the percentage of budding for 66,67%, and the storage up to four days were be able to maintain the bud viability, the percentage of budding life, the average days of the bud to sprout, and the number of leaves that as well as the buds which is budding without stored. Key word : banana sheath, budding, teak

Physicochemical and bacteriological characterization of hospital effluents and their impact on the environment

2019 ◽  
Author(s):  
Chem Int
Keyword(s):  
Human Health ◽  
Fecal Coliforms ◽  
Chemical Pollution ◽  
Hospital Effluents ◽  
Biological Contaminants ◽  
Almost All ◽  
Direct Discharge ◽  
Significant Chemical

Liquid effluents discharged by hospitals may contain chemical and biological contaminants whose main source is the different substances used for the treatment of patients. This type of rejection can present a sanitary potentially dangerous risk for human health and can provoke a strong degradation of diverse environmental compartments mainly water and soils. The present study focuses on the quality of the liquid effluents of Hassani Abdelkader’s hospital of Sidi Bel-Abbes (West of Algeria). The results reveal a significant chemical pollution (COD: 879 mgO2/L, BOD5: 850 mgO2/L, NH4+ : 47.9 mg/l, NO2- : 4.2 mg/l, NO3- : 56.8 mg/l with respect to WHO standard of 90 mgO2/L, 30 mgO2/L, 0.5 mg/l, 1 mg/l and 1 mg/l respectively). However, these effluents are biodegradable since the ratio COD/BOD5 do not exceeded the value of 2 in almost all samples. The presence of pathogen germs is put into evidence such as pseudomonas, the clostridium, the staphylococcus, the fecal coliforms and fecal streptococcus. These results show that the direct discharge of these effluents constitutes a major threat to human health and the environment.

ВЛИЯНИЕ БИОКОНСЕРВАНТА «СИЛОСТАН» НА КАЧЕСТВО СЕНАЖА ИЗ КОЗЛЯТНИКА ВОСТОЧНОГО И СЫРОПРИГОДНОСТЬ МОЛОКА КОРОВ

2019 ◽  
pp. 51-56
Author(s):  
A.S. KARAMAEVA ◽  
N.V. SOBOLEVA ◽  
S.V. KARAMAEV
Keyword(s):  
Serum Proteins ◽  
Metabolizable Energy ◽  
Holstein Cows ◽  
Technological Properties ◽  
Holstein Breed ◽  
Feed Digestibility ◽  
Ayrshire Breed ◽  
Milk Coagulation ◽  
Dry Substance

От породы коров и ее особенностей зависят эффективность использования кормов, качество и технологические свойства молока. Материалом исследований служили коровы чернопестрой голштинской и айрширской пород. Для повышения качества сенажа из козлятника восточного использовали микробиологический препарат. В готовом корме с биоконсервантом содержание сухого вещества было выше на 3,66, обменной энергии на 8,04, сырого протеина на 10,86, переваримого протеина на 13,59. Улучшение качества корма оказало положительное влияние на метаболические процессы в рубце подопытных коров. Независимо от технологии приготовления сенажа коровы айрширской породы лучше переваривали, по сравнению с голштинами, сухое вещество на 2,062,91 (Р0,05), органическое на 1,212,04 (Р0,05), сырой протеин на 2,222,49 (Р0,05), БЭВ на 0,921,36, но при этом голштины лучше переваривали сырой жир на 2,732,78 (Р0,05) и сырую клетчатку на 1,551,86. В результате внесения в сенаж биоконсерванта Силостан и улучшения переваримости корма у коров опытных групп значительно улучшился химический состав и технологические свойства молока. Очень важно для сыроделия, что в молоке коров, получавших в рационе сенаж с биоконсервантом, повышается массовая доля казеина на 2,42,7, а доля сывороточных белков и фракции казеина, которые не свертываются под действием сычужного фермента, наоборот, снижается на 1,41,5 и на 0,30,9, соответственно. Уменьшается продолжительность свертывания молока сычужным ферментом, снижаются потери сухого вещества с сывороткой, и увеличивается выход казеинового сгустка. Плотность казеинового сгустка повышается в молоке голштинских коров на 14,3, айрширских на 5,7 и составляет, соответственно, 1,92 и 2,96 г/см2.The efficiency of feed use, the quality, as well as technological properties of milk depend on cow breed and its characteristics. Blackandwhite Holstein and Ayrshire breeds were used as the material for research. Microbiological preparation was used to increase the quality of halyage made of Eastern galega. The content of dry substance in the readymade feed was 3.66 higher, the metabolizable energy 8.04 higher, raw protein 10.86 higher, and digestible protein 13.59. Improvement of feed quality positively influenced the metabolic processes in the rumen of experimental cows. Without regard to the technology of halyage preparation, cows of Ayrshire breed showed betterdigestion of dry substance by 2.06 2.91 (P0.05) than Holstein cows, organic substance by 1.21 2.04 (P0.05), raw protein by 2.22 2.49 (P0.05), nitrogenfree extractive fraction by 0.92 1.36, but Holstein breed showed better digestion of raw fat by 2.73 2.78 (P0.05) and raw fiber by 1.55 1.86. Chemical composition and technological properties of milk improved significantly as a result of addition of Silostan biopreservative to the halyage and improvement of feed digestibility in cows from test groups. The fact that the mass percentage of casein is increased by 2.4 2.7, and the share of serum proteins and ycasein fractions which do not coagulate under the influence of enzyme rennet is inversely decreased by 1.4 1.5 and 0.3 0.9, accordingly, is very important for cheese making. The duration of milk coagulation with rennet is decreased, the loss of dry substance with serum is decreased, and the yield of casein coagulate is increased. Density of casein coagulate is increased in the milk of Holstein cows by 14.3, Ayrshire cows by 5.7, and equals to 1.92 and 2.96 g/cm2, accordingly.

scholarly journals Mentors' experiences in an osteopathic medical student research program

2021 ◽  
Vol 0 (0) ◽  
Author(s):  
Tyler Hamby ◽  
W. Paul Bowman ◽  
Don P. Wilson ◽  
Riyaz Basha
Keyword(s):  
Medical Students ◽  
Research Program ◽  
Online Survey ◽  
Medical Schools ◽  
Systematic Instruction ◽  
Medical Student Research ◽  
Research Programs ◽  
Student Mentor ◽  
The University

Abstract Context Medical students, especially at osteopathic medical schools, have limited research exposure. Systematic instruction in research, supervised by qualified mentors, could motivate osteopathic medical students to pursue research in their careers, thereby increasing the number of future clinician-scientists. Recruiting and retaining suitable research mentors are crucial to sustaining such programs, but this task is also particularly challenging for osteopathic medical schools. Objectives To assess mentors' experiences in a voluntary student-mentor medical research program. Methods An online survey was sent to 76 university- or hospital-based participants who previously mentored 219 medical students between 2014 and 2019. The questionnaire consisted of 13 items with responses in checklist, five-point Likert scale, and categorical multiple-choice formats, assessing motivation for participation, satisfaction with the program, and interest in future participation. Data were analyzed descriptively, and responses from mentors at the university and hospital were compared using univariate logistic and ordinal regression analyses. Results Among 70 (92.1%) mentors who responded to the survey, 61 (87.1%) reported being motivated by a desire to help medical students learn research. Forty-nine (70.0%) mentors indicated that furthering their own research productivity was a motivation, and hospital-based mentors were statistically significantly more likely to endorse this source of motivation (OR=2.02; 95% CI=1.18–3.45; p=0.01). Most respondents were satisfied with the quality of the students' work (59 [84.3%]) and with the program (59 [85.5%]). However, 46 (65.7%) suggested the program could be enhanced by requiring medical students to be physically present in the clinic or laboratory for a minimum amount of time. Importantly, most (58 [84.1%]) mentors reported that they would be interested in participating in future mentored research programs. Conclusions Mentors were motivated to participate in the voluntary research program for both altruistic and professional reasons. Since most mentors reported being satisfied with the program, it is likely they would participate in future mentored research programs. Our results suggest that mentors viewed this voluntary research program as mutually beneficial.

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