scholarly journals Influence of jeringau (Acorus calamus Linn.) rhizome extract against dry-wood termites (Cryptotermes cynocephalus Light.)

2021 ◽  
Vol 914 (1) ◽  
pp. 012054
Author(s):  
A Ismanto ◽  
I Anggraeni ◽  
D A Agustiningrum ◽  
Y Ardiansyah

Abstract Rubberwood (Hevea brasiliensis Muell Arg.) is classified as a hardwood, yet it is vulnerable to dry-wood termites attack, namely Cryptotermes cynocephalus Light. Hence, a preservative is necessary for prevention. The purpose of this research was to examine the effect of jeringau rhizome extract on dry-wood termites C. cynocephalus attack. The experimental design was a completely randomized factorial design with two factors include 2 levels of solvent (water and ethanol) and 4 levels of extract ratio (1:4, 1:6, 1:8, and 1:10). Parameters observed were actual retention, termites mortality, sample weight loss, and attack degree. Rubberwood was sized in 5 cm x 3 cm x 3 cm. The method used was immersing the samples in a container that contains jeringau rhizome extract in various treatments for 72 hours. The immersed samples were then fed to healthy and active C. cynocephalus for 12 weeks. The results showed that the type of solvents and extract ratio had a significant effect on termites mortality and samples weight loss, while actual retention was influenced by the extract ratio. In conclusion, the most effective formula to prevent dry-wood termites attack was jeringau rhizome extract with a weight ratio of jeringau powder and ethanol 1:6.

1997 ◽  
Vol 51 (7) ◽  
pp. 1060-1066 ◽  
Author(s):  
Won B. Cho ◽  
Young A. Woo ◽  
Hyo J. Kim ◽  
Il J. Kim ◽  
Won K. Kang

Comparisons between direct-current (dc) and radio-frequency (rf) gas jet-boosted glow discharge atomic emission spectrometry (GD-AES) have been made with regard to fundamental characteristics and analytical performance. The study of fundamental characteristics includes the voltage—current relationship; a gas flow rate of 0 mL/min to 800 mL/min and pressures ranging from 3 Torr to 5 Torr on dc bias potential; the sample weight loss; and the emission intensity. The dc-powered glow discharge at 90 mA/450 V and 60 mA/710 V at 5 Torr shows 3 × more sample weight loss than the rf discharge at 40 W. Radio-frequency glow discharge shows a short-term precision of <1% relative standard deviation (RSD) and a long-term stability of <5% RSD for both major and trace element lines. Both rf and dc show calibration curves that are linear over 2–3 orders of magnitude, with a general improvement in linearity from ratioing the signal to an internal standard of the matrix. Further improvement of linearity was possible by correcting the bias potential in the rf glow discharge. Limits of detection (LODs) for rf are tens of parts per billion from many trace elements in low-alloy steel, which is one order of magnitude improvement over those for dc.


2010 ◽  
Vol 5 (1) ◽  
Author(s):  
Nayef M. Ghasem

The polyamides used for hot-melt adhesives were synthesized from C36 dimer fatty acids and ethylenediamine under 200 mmHg and atmospheric pressures. The kinetics of the reaction rate at low pressure and the effect on the thermal properties of the produced polyamide adhesive were experimentally investigated. The effects of reaction temperature and catalyst concentration on polyamide melting point, glass transition temperature, sample weight loss and foaming height were studied. The kinetic rate constants were obtained for polymerization reaction carried out at three different reaction temperatures, 115, 120, and 135 °C, fixed mixing rate of 100 rpm and low operation pressure of 200 mmHg. Polymers produced at atmospheric pressure and reaction temperatures 140, 170, 180, and 190 °C where used to investigate the polyamide thermal properties using thermal gravimetric analysis (TGA) and differential scanning calorimetry (DSC). Thermal properties such as melting point, glass transition temperature and the temperature at which 5% and 10% weight loss were recorded by TGA at a heating rate of 10 C/min in N2 atmosphere. The effect of foaming height as a function of reaction temperature and catalyst concentration was measured. The analysis makes known that the reaction temperature and catalyst concentration has a noteworthy impact on the glass transition temperature, foam height and melting point and insignificant effect on the sample weight loss.


2015 ◽  
Vol 4 (2) ◽  
pp. 50-55
Author(s):  
Sandra J Nendissa ◽  
Rachel Breemer ◽  
Nikholaus Melamas

This objectives of this research were both to study and determine the best level of concentration of yeast Saccharomyces cereviseae and period of fermentation on the quality of tomi-tomi vinegar (Flacourtia inermis). A completely randomized experimental design with two factors of treatment was applied in this research. The first factor was concentration of yeast S. cereviseae having four levels of tretament, i.e.: without the addition of yeast 0.5, 1 and 1.5 g yeast. The second factor was period fermentation with 1, 2, 3, 4, and 5 weeks. The result indicated that the concentration of yeast S. cereviseae 1.5 g and period fermentation 5 week produced a good tomi-tomi vinegar with total acids 51.22%, total dissolved solids 8.35, total sugar 8.07% and pH 5.40.


2014 ◽  
Vol 494-495 ◽  
pp. 461-465 ◽  
Author(s):  
Bao Shou Sun ◽  
Zhe Hong ◽  
Long Qing Xu ◽  
Xue Dao Shu ◽  
Bo Qin Gu ◽  
...  

This paper simulates the process of the high-neck flange closed rolling on DEFORM-3D and optimizes the rolling process parameter by analyzing the results based on the orthogonal experimental design. For the high-neck flange, the results show that the effects on ellipticity are in the order of the mandrel feed speed, the main roll rotational speed and initial blank temperature. The former two factors show the significance while the initial blank temperature does not show that.


2017 ◽  
Vol 18 (4) ◽  
pp. 549-559
Author(s):  
Elisângela Borsoi Pereira ◽  
Magali Soares dos Santos Pozza ◽  
Paula Martins Olivo ◽  
Osmar Dalla Santa ◽  
Suzana da Cruz Pires ◽  
...  

SUMMARY Cheese is the oldest form of preserving milk nutrients having nutritional, economic and cultural importance. The objective of this study was to identify the best time of the year for production, and period, in months, for maturation of traditional colonial cheese, through analysis of water activity, weight loss and counts of lactic acid, mesophilic microorganisms—proteolytic and lipolytic. Records of temperature and relative humidity (RH) were maintained. A completely randomized experimental design was used in a double factorial scheme, considering production periods and maturation times. For all production periods evaluated, there was a significant reduction in the periods for water activity values. The counts of lactic acid bacteria ranged from 104 to 109 CFU/g. There was also stability in the number of colonies for lipolytic mesophilic microorganisms, until the third month of maturation. Low counts of proteolytic mesophiles were observed for the samples produced in May and June (5.70 and 5.53 log), respectively. The production period for the months of May and June corresponding to RH of 80% and average temperatures of 15°C were the most effective for production. Due to the presence of Listeria, it is recommended to respect the minimum time of 60 days of maturation for commercialization.


2018 ◽  
Vol 1 (2) ◽  
Author(s):  
Agus Ngadianto ◽  
Ganis Lukmandaru ◽  
Dhuria Maulidya Sari ◽  
Utari Mardatillah ◽  
Dera Fara Fitria

Binderlessboard is one of the potential eco friendly products that can be developed. Utiliation of natural adhesives for non-wood composite is still very limited. Therefore, this research is focused on effects of citric acid content and pressing time on characteristics of particleboard made from peanut shell including its durability to dry wood termite attacks. Peanut shell particles were used as raw materials. Citric acid dissolved in liquid smoke which functioned as a water substitute solvent under a certain ratio and the concentration of the solution was adjusted to 60%. The use of liquid smoke is expected to increase the durability of the particleboard. Factors used in this research were citric acid content (10-30% based on dry weight particles) and pressing time (10 minutes and 15 minutes). Properties of particleboard were analyed based on Japanese Industrial Standard (JIS) A 5908 for particleboard. The dry wood termite resistance was then analyzed for its weight loss and mortality after 4 weeks. The results showed that the best particleboard was obtained from the treatment of 30% citric acid content with 15 minutes of pressing time where only the modulus of rupture and modulus of elasticity did not met the requirement of JIS A 5908 type 8 with the thickness swelling were 3.276%, water absorption were 44,991%, internal bonding were 4.679 kgf / cm², modulus of rupture were 26.822 kgf / cm², and modulus of elasticity were 8,986,058 kgf / cm². The best value of weight loss and mortality of dry wood termites on particleboard was obtained in a combination of 30% citric acid content with 10 minutes pressing time were 1.083% and 38.67% respectively.


Author(s):  
Diarrassouba Moussa ◽  
Soumahin Eric Francis ◽  
Konan Djézou ◽  
N’guessan Kan Pulchérie ◽  
Moro Affia Perpetue ◽  
...  

To find out the effect of cultural techniques on agrophysiological parameters, four combinations ̏planting densities (low density or DF at 350 t/ha, normal density or DN at 510 t/ha) and opening standards (opening at 65cm and opening at 50 cm) ̋ were tested on Hevea brasiliensis clones PB 260, IRCA 111 and RRIM 703. This study was conducted for nine years with a split-plot experimental design of two treatments and two subtreatments repeated three times. The different combinations of treatments and subtreatments tested were low density (DN-50 cm), low density (DN-65 cm), normal density (DF-50 cm), normal density (DF- 65 cm). The parameters evaluated were the production at bleeding and per hectare, the average annual increase in circumference, the rate of tree losses and the rate of trees with dry notches. Production per tree was significantly higher at 350 t/ha and 65 cm opening (DF-65 cm), while per hectare production was higher at 510 t/ha. The girths of the different clones are stronger at DF and at the 65 cm opening. The rate of tree loss and the rate of trees with dry notch were low at the 510 t/ha density and the 65cm opening. The appropriate density and opening standard was "normal density 510 t/ha and opening to circumference 50 cm". The cultivation techniques especially the density and opening standard judiciously applied can participate in the sustainable improvement of rubber productivity of rubber plantations.


AGRICA ◽  
2020 ◽  
Vol 10 (2) ◽  
Author(s):  
Kristono Yohanes Fowo

Land Productivity and NKL on Tumpangsari Three Maize Variety Cultivation (Zea mays caratina Kulesh) With Various Interval Time Plants (Archis hipogaea L.) as Select Plant. This study aims to determine the combination of timing planting and planting techniques that can improve the productivity of land and NKL values ??on the application of intercropping cultivation technology in dry land conditions in Ende-NTT. The experimental design using Division Split Plot (RPT) consists of two factors repeated three times. The treatment of corn varieties (V1: Local varieties, V2: Uri varieties, V3: Binthe Pulu varieties) while planting time was placed as subplot (T1: Maize planted 15 days after peanut planting T2: Corn is grown together with peanut planting T3: Corn is grown 15 days before planting peanuts, as comparison of each treatment is also planted in monculture, so that obtained 31 units of experiment plot The data collection is done by calculating dry weight of seeds produced by all plant crops in the harvest plots, and the crops in the harvest plots. The results show that intercropping crops between pulut and peanut crops in various pulses maize varieties and peanut planting times increased the productivity of the land 1, with the highest land productivity dida The maize varieties of Uri corn is grown simultaneously with groundnut planting (V2T2) of 1.52 and followed by treatment of local varieties of pulutans planted together with peanut plant (V1T2) of 1.46.


2021 ◽  
Vol 2021 ◽  
pp. 1-17
Author(s):  
T. Sathish ◽  
S. Tharmalingam ◽  
V. Mohanavel ◽  
K. S. Ashraff Ali ◽  
Alagar Karthick ◽  
...  

Aluminium and its alloys play a significant role in engineering material applications due to its low weight ratio and superior corrosion resistance. The welding of aluminium alloy is challenging for the normal conventional arc welding processes. This research tries to resolve those issues by the Tungsten Inert Gas welding process. The TIG welding method is an easy, friendly process to perform welding. The widely applicable wrought aluminium AA8006 alloy, which was not considered for TIG welding in earlier studies, is considered in this investigation. For optimizing the number of experiments, the Taguchi experimental design of L9 orthogonal array type experimental design/plan was employed by considering major influencing process parameters like welding speed, base current, and peak current at three levels. The welded samples are included to investigate mechanical characterizations like surface hardness and strengths for standing tensile and impact loading. The results of the investigation on mechanical characterization of permanent joint of aluminium AA8006 alloy TIG welding were statistically analyzed and discussed. The 3D profilometric images of tensile-tested specimens were investigated, and they suggested optimized process parameters based on the result investigations.


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