Tingkat Keberhasilan Perpindahan Koloni Trigona Spp. pada Sarang Buatan di Hutan Larangan Adat Desa Rumbio Kabupaten Kampar

Trigona spp. is include into stingless bee honey. Trigona spp. has another names, such as, galo-galo (Sumatera), klanceng, lenceng (Jawa), andteuweul (Sunda). The population of Trigona spp. in many areas in Indonesia. Trigona spp. produce are honey, pollen, royal jelly, propolis and beeswax. People do not know much yet about the benefit and how to cultivation of Trigona spp. type, material and size of bee\u27s nest. The purpose of this research is to know successfull affectiveness movement of Trigona spp. in type, material and size of artificial nest. This research used two method, survey and experiment. The first survey got 19 bee\u27s nest of Trigona spp. in 7 trees. In the next experiment, the resercher tried to test 6 artificial nests (2 bee\u27s nest made by half of a coconut shell, 2 bee\u27s nest made by bamboo and 2 bee\u27s nest made by wooden box) and the different size of box. The experiment of 6 artificial nests was a theory of eduction/attachment. The artificial nest affixed to red chelate tree (Syzygium sp.), kempas (Koompassia malaccensis), jackfruit (Artocarpus heterophyllus) and red chelate tree was moudly/dead. The result of this research show that type of Trigona spp. that lifeatThe Prohibition Forest of Indigenous Village of Rumbio Kampar Regency. There are three kinds : Trigona collina, Trigona incica andTrigona terminata. The preferred and ideal artificial nest of Trigona spp. was wooden box 3 segment in Ttot = 65 cm, basic segment T1 =30 cm, middle segment T2 =25 cm andtop segment T3 = 10 cm

Tingkat Keberhasilan Perpindahan Koloni Trigona Spp. pada Sarang Buatan di Hutan Larangan Adat Desa Rumbio Kabupaten Kampar

Trigona spp. is include into stingless bee honey. Trigona spp. has another names, such as, galo-galo (Sumatera), klanceng, lenceng (Jawa), andteuweul (Sunda). The population of Trigona spp. in many areas in Indonesia. Trigona spp. produce are honey, pollen, royal jelly, propolis and beeswax. People do not know much yet about the benefit and how to cultivation of Trigona spp. type, material and size of bee\u27s nest. The purpose of this research is to know successfull affectiveness movement of Trigona spp. in type, material and size of artificial nest. This research used two method, survey and experiment. The first survey got 19 bee\u27s nest of Trigona spp. in 7 trees. In the next experiment, the resercher tried to test 6 artificial nests (2 bee\u27s nest made by half of a coconut shell, 2 bee\u27s nest made by bamboo and 2 bee\u27s nest made by wooden box) and the different size of box. The experiment of 6 artificial nests was a theory of eduction/attachment. The artificial nest affixed to red chelate tree (Syzygium sp.), kempas (Koompassia malaccensis), jackfruit (Artocarpus heterophyllus) and red chelate tree was moudly/dead. The result of this research show that type of Trigona spp. that lifeatThe Prohibition Forest of Indigenous Village of Rumbio Kampar Regency. There are three kinds : Trigona collina, Trigona incica andTrigona terminata. The preferred and ideal artificial nest of Trigona spp. was wooden box 3 segment in Ttot = 65 cm, basic segment T1 =30 cm, middle segment T2 =25 cm andtop segment T3 = 10 cm

Assessment of Some Old Earth Dams in Malaysia Through Observation and Computer Simulation

In this study, two earth dams located in Malaysia were studied. The Labong Dam is a non-homogenous earth dam, whilst the Bukit Merah Dam is a homogenous earth dam. The performances of both dams against seepage were studied through the analyses of both observed and simulated phreatic surfaces. Simulations of seepage rate and phreatic surfaces through the dam were conducted by using SEEP/W model. The study showed that the SEEP/W model was able to predict (simulate) both the seepage rates and phreatic surfaces of the homogeneous and non-homogeneous earth dams with a reasonable accuracy. The Absolute Error (AE) between the predicted and observed seepage rates of both dams were found to be 0.03 m3/min to 0.18 m3/min. The average AE in the predicted phreatic surfaces for the maximum and minimum water levels in the reservoir were 0.6 m and 0.38 m for the non-homogeneous dam (Labong Dam), and 0.595 m and 0.75 m for the homogeneous dam (Bukit Merah Dam)

Fabrication and machining performance of ceramic cutting tool based on the Al2O3-ZrO2-Cr2O3 compositions

This study presents the cutting tool development of zirconia toughened alumina (ZTA) with chromia addition. The process used for its development is solid-state, in which the powders of Alumina (Al2O3), Zirconia (ZrO2) and Chromia (Cr2O3) were processed by a ball mill, com�pacted under a Cold Isostatic Press (CIP) and sintered at a constant temperature of 1400 ◦C with 9h soaking time. The initial study investigated the effect of Polyethylene glycol (PEG) as a binder, CIP and hardness of Al2O3-ZrO2 mixtures. The percentage composition between Al2O3 and ZrO2 was varied to choose the best for the highest mechanical performances determined by the density, porosity and properties analysis. The cutting tool that possessed the highest hardness and bending strength was selected the Al2O3-ZrO2 mixture was mixed 0.6 wt% Cr2O3 for machining trials within the cutting speed of 200–350m/min and constant feed rate and depth of cut of 0.150mm/rev and 0.5mm, respectively. The results of the ZTA mixed with Cr2O3 and combined with the ratio 80-20-0.6 wt% showed that the addition of 0.6 wt% PEG and a CIP pressure at 300 MPa and 60 s dwell time resulted maximum hardness and bending strength of 71.03 HRc and 856.02 MPa, respectively. The fabricated cutting tool was capable to reach 225 s tool life when machining AISI 1045 at a lower cutting speed of 200 m/min and higher feed rate of 0.150mm/rev

Comparison machining performance of Al2 O3 , ZTA and ZTA doped Cr2 O3 cutting tools on AISI 1045

This paper presents the comparison of machining performance for cutting tools that fabricated by pure alumina (Al2O3), Zirconia Toughened Alumina (ZTA) and Zirconia Toughened Alumina doped with Cr2O3 (ZTA Doped Cr2O3). Solid-state method was employed to prepare ceramic mixtures starting from 12 h ball milling with 40 rpm rotational speed. The green bodies were formed by 5 ton manual hydraulic press and 300 MPa Cold Isostatic Press (CIP) compaction pressure. The compacted powders then were sintered at 1400 °C and 9 h soaking time in the form of RNGN 120600 designated cutting tools. Properties assessment of the fabricated cutting tools were analysed based on hardness and density. The machining evaluation was performed by turning AISI 1045 with cutting speeds of 150–350 m min−1, feed rate of 0.125 mm/rev and depth of cut of 0.5 mm. The results show that maximum hardness recorded for ZTA Doped Cr2O3 with 13.73 GPa Vickers hardness and 3.82 g cm−3 density, followed by ZTA (12.75 GPa, 3.85 g cm−3) and pure Al2O3 (4.9 GPa, 3.76 g cm−3)In terms of machining performance, ZTA Doped Cr2O3 recorded highest tool life of 330-s with 57% improvement of tool life as compared to ZTA (210-s) and 200% improvement of pure Al2O3 (110-s). Dominant wear mechanisms for the fabricated cutting tool appeared to be notch wear, abrasive wear and chipping at the flank wear area

Observation of built-up edge formation on a carbide cutting tool with machining aluminium alloy under dry and wet conditions

This paper presents the morphology of built-up edge (BUE) formation under wet and dry conditions with low and high cutting speeds. The workpiece materials and cutting tools selected for this work were aluminium alloy and canela carbide inserts graded PM25. The cutting tools underwent turning operation machining tests and their performance was evaluated by the flank wear and observation of the tool wear area. The machining tests were conducted at different spindle speeds and feed rates while the cut depth was kept constant. The analysis showed that formation of the BUE was dominant at low cutting speeds in dry conditions, but in wet conditions at high cutting speeds, a better performance was exhibited in terms of wear analysis

Research of biochemical gold recovery method using high-arsenic raw materials

This article contains the results of experiments to recover gold from complex mineral raw materials containing more than 15 % arsenic. Laboratory tests showed that standard cyanidation recovers only 26,4 % of gold into the solution. Additional oxidizing reagents used increase the leaching efficiency and enable to recover more than 40 % of gold during subsequent cyanidation. The efficiency has been established for replacement of cyanide with thiourea and thiosulfate solutions. 79,5 %, i.e. the maximum recovery rate, was found in the experiment with preliminary oxidation with T. Ferrooxidans, a bacterial culture, followed by leaching with a thiourea solution

Research of biochemical gold recovery method using high-arsenic raw materials

This article contains the results of experiments to recover gold from complex mineral raw materials containing more than 15 % arsenic. Laboratory tests showed that standard cyanidation recovers only 26,4 % of gold into the solution. Additional oxidizing reagents used increase the leaching efficiency and enable to recover more than 40 % of gold during subsequent cyanidation. The efficiency has been established for replacement of cyanide with thiourea and thiosulfate solutions. 79,5 %, i.e. the maximum recovery rate, was found in the experiment with preliminary oxidation with T. Ferrooxidans, a bacterial culture, followed by leaching with a thiourea solution

An Upgraded Transverse Electromagnetic Parallel Plates for Dielectric Measurement

A new version of transverse electromagnetic parallel plates with irregular plates’ width and plate separation has been developed for dielectric measurement. The separations between the plates are supported by four rectangular Teflon block and 1 mm of groove is proposed at the center of the upper plate to maintain the measurement repeatability. The groove enables the samples which are slightly higher than 2 cm to be fitted well between the plates without introducing extra force to the plates. Theperformance of both parallel plates has been compared in the frequency range from 100 MHz to 1.1 GHz. It is found that the upgraded parallel plate offers better return loss and insertion loss above 500 MHz compared to the previous parallel plate. It is reported from this work that the return loss of the parallel plate must be lower than -15 dB in order to achieve accurate dielectric constant. However, the insertion loss of the parallel plates does not influence the real permeability significantly. The upgraded TEM parallel plateproduces a consistent reading with a standard deviation of less than 0.05 above frequency 200 MHz. The dielectric measurement of Polypropylene (PP) has proven the capability of this upgraded TEM parallelplate

Greenhouse gas (GHG) emissions from land transports in Malaysia: modelling and policy analysis

Transportation sector is important to the economy and its rapid development has contributed significantly to the socioeconomic development of the country. The transportation sector in Malaysia accounts for approximately 35% of the total energy consumed nationally and produces nearly 50 million tonne of CO2 per year in 2015, second only to electricity power generation. Though shares only 0.3% of global GHG (Greenhouse gas) emissions, Malaysia is second largest per capita GHG emitter among the group of ASEAN countries and the major concern lies in the ever increasing trends. The aim of this work was to perform dynamic quantitative emission analysis of Malaysian vehicle fleet until year 2040, primarily on land transports including both passenger and freight transports except train. Utilizing a System Dynamic approach using Powersim Studio®, several emission scenarios were modelled in compared to current scenario (baseline model). The baseline model was used to determine carbon dioxide (CO2), carbon monoxide (CO) and nitrogen oxides (NOx) reduction for different policy scenarios in compared to baseline scenario. The complex relationships between the various components in the transport system are reflected in the dynamic model considering the vehicle technology, legislation and drivers’ attitude. This work found that CO2 emission in 2040 can be reduced by up to 50%, compared to baseline scenario, without affecting the economy and vehicle demand. Carbon dioxide and nitrogen oxides pollution can also be reduced by 75% and 93% respectively with implementation of several policies compared to baseline scenario