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INHIBISI INSEKTISIDA KARBAMAT DAN ORGANOFOSFAT PADA ASETILKHOLINESTERASE LEBAH MADU
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| Pengarang | : | lip Izul Falah |
| Nama Majalah/Jurnal | : | Berkala Ilmiah MIPA |
| Volume / Edisi | : | 18 (No. 1) |
| Halaman | : | 56-62 |
| Abstrak | : | It is generally already accepted that organophosphate and carbamate insecticides function due to their ability to disrupt the transmission of impulses at certain synaptic junctions in the nervous system by inhibition of acetylcholinesterase. Type of inhibition reaction of carbamate (Baycarb and MIPC) and organophosphate (Dichlorvos and Monochrotophos) insecticides on honey-bee acetylcholinesterase (AChE) is shown in this investigation.For this study, the enzyme was produced by extraction of honey-bee heads using 0.01 M and pH 7.0 aqueous phosphate buffer solution, while N-methylindoxyl acetate (MIA) in absolute methanol at concentration of 0.005 g/mL was used as a substrate stock solution. Enzyme activity was detected using HPLC spectrofluorometer at 450 nm and 495 nm for excitation and emission wavelength, respectively. Based on detection of initial reaction rate between the enzyme with carbamate or organophosphate, it could be concluded that the reactions were competitive inhibition. |
STUDY OF REACTION PATHWAY AND KINETIC OF ESTRAGOLE ISOMERIZATION TO CJS-ANETHOLE AND TRANS-ANETHOLE
| Pengarang | : | Asep Kadarohman1, Gebi Dwiyanti, M. Muchalat, Rizki Maryam Astuti |
| Nama Majalah/Jurnal | : | Berkala Ilmiah MIPA |
| Volume / Edisi | : | 18 (No. 1) |
| Halaman | : | 51-55 |
| Abstrak | : | Estragole isomerization in basic condition resulted cis- and trans-anethole. Hence, there were two reaction pathway of estragole isomerization i.e. parallel and consecutive. The reaction pathway gave information about reaction mechanism. Estragole isomerization was carried out in various kind and volumeof solvent, base ratios, and at various time and temperature. The products were analyzed by GC-MS, and FTIR. The result showed that the estragole isomerization pathway in ethanol and ethylene glycol was parallel. The mec |
EFFECT OF K2SO4 TO THE PORE PROPERTIES OF PRODUCTS IN THE SYNTHESIS OF MESOPOROUS SILICATES MCM-41
| Pengarang | : | Suyanta, Narsito, Endang Tri Wahyuni, Triyono, and Sutarno |
| Nama Majalah/Jurnal | : | Berkala Ilmiah MIPA |
| Volume / Edisi | : | 18 (No. 1) |
| Halaman | : | 43-50 |
| Abstrak | : | Researchs about the effects of K2SO4 to the pore properties of the products in the synthesis of mesoporous silicates MCM-41 has been done. MCM-41 was synthesized by hydrothermal treatment of the mixture containing : 9.31 of sodium silicate solution, 8.67 g of cetyltrimetylammoniumbromide (CTMAB) and 29 g of distilled water (molar ratio of 8 Na2SiO3 : CTMAB : NaOH : 400H2O). The hydrothermal treatment was carried out at 100 °C in a teflon-lined stainless steel autoclave heated in the oven for 36 h. The solid phase was filtered, washed with distilled water, and dried in the oven at 100 °C for 2 h. The surfactant CTMAB was removed by calcinations at 550 °C for 10 h with heating rate of 2 °C/min. The as-synthesized MCM-41 was characterized by using FTIR spectroscopy and X-ray diffraction, while calcined-MCM-41 was characterized by using FTIR spectroscopy, X-ray diffraction; and N2 physisorption methods. The same procedure was carried out, with the addition of 17.4 g of K2SO4 and 21.6 ml of distilled water to obstain the molar composition of the gel of: 8Na2SiO3 : CTMAB : Na OH: 400H2O : 2 K2SO4• The results showed that the addition of K2SO4 increased the crystalinity. MCM-41 prepared with K2SO4 has a higher specific surface area of 972.812 m2 g·1 compared to the MCM-41 prepared without K2SO4 (i.e., 946.607 m2 g"1 ), higher mean pore diameter of 3. 714 nm compared to the MCM-41 prepared without K2SO4 (i.e. 3.357 nm), and thicker pore walls of 0.830 nm compared to the MCM-41 prepared without K2SO4 (i.e. 1.176 nm). Key words : MCM-41, K2SO4, pore properties |
BASIS PENGETAHUAN DENGAN MODEL KEPUTUSAN KELOMPOK UNTUK DIAGNOSIS GANGGUAN KEJIW AAN
| Pengarang | : | Sri Kusumadewi, Sri Hartati |
| Nama Majalah/Jurnal | : | Berkala Ilmiah MIPA |
| Volume / Edisi | : | 18 (No. 1) |
| Halaman | : | 29-42 |
| Abstrak | : | A knowledge base is the most important part in expert systems. A knowledge in the knowledge bases can be represented in several mechanisms. But any knowledge bases not accomodate some preferences from a group decision makers yet. In this research, knowledge was built from preference given by some decision makers. The decision makers (the experts) role's are give their preferences about mental disorder diagnosis. The prefereces involve some features in a particular condition and some related disorders. In this research, we have had 124 features, 30 disorders, and 105 conditions. The decision makers gave their preferences in utility vectors format. The disorder preferences in a particular condition were given in selected subsed vectors format. Each vector was transformed to fuzzy preference relation matrix to compose these preferences in the single aggregation matrix. We used Ordered Weighted Averaging (OWA) operator to compose these preferences. Finally, we used Quantifier Guided Dominance Degree (QGDD) operator in exploitation phase to rank the relevant features and some disorder alternatives which were influented. The exploitation means were choosen as threshold values to decide the relevant features and disorders. The experimental results is 635 knowledges in a knowledge base that is represented in IF - THEN format. |
THE ANALITICAL SOLUTIONS OF THE LINEAR TWO CHANNELS DISSIPATION MODEL
| Pengarang | : | Sumardi, Soeparna Darmawijaya, Lina Aryati |
| Nama Majalah/Jurnal | : | Berkala Ilmiah MIPA |
| Volume / Edisi | : | 18 (No. 1) |
| Halaman | : | 21-27 |
| Abstrak | : | The analytical solutions of the linear two channels dissipation model are presented in various forms. First we analyze the particular solutions of this model. Then the model is transformed into the Telegrapher Equation and further into the Klein Gordon Equation for which various families -of solutions are known. The Fourier Transform is applied on the Telegrapher Equation, yielding solutions in Fourier representation. Finally we apply the method of characteristics to find solutions of the initial value problem. |
SISTEM STATE-BASED dan KOALJABAR
| Pengarang | : | Yunita Septriana, Fitriani, Jeinne Mumu, lndah Emilia Wijayanti |
| Nama Majalah/Jurnal | : | Berkala Ilmiah MIPA |
| Volume / Edisi | : | 18 (No. 1) |
| Halaman | : | 14-20 |
| Abstrak | : | In this paper we consider state-based systems as a F-coalgebra. The crucial notion of the definition of a coalgebra Jl is a mapping «,,i which maps from the base set A to F(A) for some set-valued functor F. The definition of an F-coalgebra could be generalized to any category e using a functor F:C ? C .The concept of a bisimulation plays a central role in the theory of coalgebra. A bisimulation between two coalgebra is a binary relation between their base sets. We pres |
TENT ANG MEKANIKA DALAM RU ANG T AK-ISOTROP
| Pengarang | : | Muhammad Farchani Rosyid |
| Nama Majalah/Jurnal | : | Berkala Ilmiah MIPA |
| Volume / Edisi | : | 18 (No. 1) |
| Halaman | : | 6-13 |
| Abstrak | : | The posibility that a tensorial mass concept is needed in physics is discussed. The concept of the tensorial mass is proposed to be a generalization of the usual mass concept in which mass is regarded as a tensor quantity. How mass tensors are involved into the dynamical equations on the classical as well as on the quantum mechanical level is persented. The quantum description of a physical system involving a tensorial mass is obtained by making use of geometric quantization soon after the classical one is constructed. Some influences of the mass tensor on the dynamical equation are studied via two cases of configuration spaces. |
CRITICAL CURRENT ENHANCEMENT USING HOLES
| Pengarang | : | Harsojo, Kamsul Abraha, Pekik Nurwantoro |
| Nama Majalah/Jurnal | : | Berkala Ilmiah MIPA |
| Volume / Edisi | : | 18 (No. 1) |
| Halaman | : | 1-5 |
| Abstrak | : | The critical current densities of superconductor having arrays of square holes and lines hole exposed under electric and perpendicular magnetic field are calculated using time dependent Ginzburg-Landau equation (TDGLE). The result shows that the addition of an array of hole and lines hole enhance the critical current density through different pinning mechanism. The enhancement of critical current by an array of hole addition enhances the critical current densities through commensurate effect and produces the critical current peaks at matching magnetic fields while the addition lines hole to superconductor enhances the critical current through a simple pinning |
Holistic Grammar Through Socratic Questioning
| Pengarang | : | Annie K. Koshi |
| Nama Majalah/Jurnal | : | Info Bahasa |
| Volume / Edisi | : | XII-6, NOVEMBER (No. 6) |
| Halaman | : | 10-19 |
| Abstrak | : | - |
Grammar Graups In the Student-Centered Classroom
| Pengarang | : | - |
| Nama Majalah/Jurnal | : | Info Bahasa |
| Volume / Edisi | : | XII-6, NOVEMBER (No. 6) |
| Halaman | : | 3-9 |
| Abstrak | : | - |