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All Journal Jurnal Pendidikan Kimia Indonesia Jurnal Matematika & Sains Jurnal Penelitian Pendidikan IPA (JPPIPA) Jurnal Akademika Kimia Indonesian Journal of Chemistry JMM (Jurnal Masyarakat Mandiri) Jurnal Ilmiah Kanderang Tingang Journal of Educational Chemistry (JEC) Patria : Jurnal Pengabdian Kepada Masyarakat Jurnal Riset Pendidikan MIPA Jurnal Abdimas Ilmiah Citra Bakti (JAICB) Mattawang: Jurnal Pengabdian Masyarakat JSEP (Journal of Science Education and Practice) Jurnal Akademika Kimia Jurnal Ilmu Pendidikan Indonesia JIPI (Jurnal IPA dan Pembelajaran IPA) Mitra Sains Jurnal Akademika Kimia
Daud Karel Walanda
Pendidikan Kimia FKIP Universitas Tadulako Palu Indonesi 94119
Agriculture, Biological Sciences & Forestry Arts Humanities Biochemistry, Genetics & Molecular Biology Chemical Engineering, Chemistry & Bioengineering Chemistry Computer Science & IT Education Engineering Environmental Science Health Professions Languange, Linguistic, Communication & Media Law, Crime, Criminology & Criminal Justice Materials Science & Nanotechnology Mathematics Physics Public Health Social Sciences Other

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General Principles in Electrospray Mass Spectrometry: A New Technique in Mass Spectral Analysis Djulia Onggo; Daud K. Walanda; Robert C. Burns; Geoffrey A. Lawrance; Ellak I. von Nagy-Felsobuki
Jurnal Matematika & Sains Vol 3, No 2 (1998)
Publisher : Institut Teknologi Bandung

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Abstract

Electrospray mass spectrometry analyzes ions which have been generated in the gas-phase from electrically charged droplets obtained by nebulizing a solution. While the generation of an aerosol by electrospray was published by Zeleny in 1917, it was not until approximately some seven decades later when it was successfully interfaced to a mass spectrometer, thereby extending significantly the use of mass spectrometry in inorganic, biological and trace element research. The mechanism of ion generation by electrospray is still not definitively understood nor is the limitation of its linear dynamic range with respect to analyte concentration. This review will describe the general principles underlying this new technique.
MODEL PEMBELAJARAN KOOPERATIF TIPE STAD (STUDENT TEAMS ACHIEVEMENT DIVISION) DIKOMBINASIKAN DENGAN MEDIA ANIMASI PADA MATERI LAJU REAKSI KELAS XI SMA NEGERI 1 PALU Berlin, I Dewa Gede; Walanda, Daud K.; Ratman, Ratman
Jurnal Akademika Kimia Vol 2, No 3 (2013)
Publisher : Universitas Tadulako

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Abstract

Students have difficulties in understanding chemistry subject contained mathematical calculation like on reaction rate topic. Cooperative learning model STAD type can be an alternative for the material contained calculation whereas animation media is for conceptual understanding. The objective of the research was to determine the influence of cooperative learning model STAD type combined with animation media for the eleventh grade students of SMA Negeri 1 Palu in academic year 2012/2013 toward the students’ learning outcome on reaction rate material. This research was quasy experimental using posttest-only control group design. The population was the whole eleventh grade students of science program with the sample determination using purposive sampling method. The sample were class of science program 2 as the experimental class which using cooperative learning model STAD type with animation media whereas class of science program 4 as the control one which using convensional learning method. The research results showed that cooperative learning model STAD type combined with animation media at reaction rate material gave students’ learning outcome higher than convensional method.
Penerapan Model Pembelajaran Koopeartif Tipe Cooperative, Integrated, Reading and Composition (CIRC) Pada Materi Struktur Atom dan Sistem Periodik Unsur Kelas X SMAN 1 Pasangkayu Yuliana, Dewi; Walanda, Daud K.; Ratman, Ratman
Jurnal Akademika Kimia Vol 3, No 1 (2014)
Publisher : Universitas Tadulako

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Abstract

Reaserch was conducted on the atomic structure subject and the periodic table with implementing cooperative learning model type of coopeative, integrated reading and composition (CIRC) in SMAN 1 Pasangkayu is applied to the learning model with the conventional lecture method. This study aims to implement cooperative learning model of CIRC towards the chemical learning outcomes. The population in this study is a class X student of SMAN 1 Pasangkayu academic year 2013/2014 the number of students 300 people, and the study sample X.4 class as experiment class with (n = 30) applying cooperative learning model CIRC and class X.3 as class control the number of students (n = 32) whithout using cooperative learning model CIRC. Testing the hypothesis t-test of the right-hand side. The results of the analysis of data obtained average scores on the experimental class = 76.90 and 60.81 for the control class normaly distibuted both classes and has variance (F test) are homogeneous. Tesing hypothesis obtained tcount t-test = 4.73 > ttabel = 1.67 with a significance level (α) = 0.05. The results showed that the application of cooperative learning model CIRC gives the positive effect on student learning outcomes in the atomic structure subject and the periodic table of elements (H0 rejected H1 is accepted).
Penerapan Model Pembelajaran Snowball Throwing Berbantuan Kode SMILES pada Materi Hidrokarbon Terhadap Hasil Belajar Siswa Kelas XI SMA Negeri 5 Palu Djahir, Ahmad Rifaldi; Walanda, Daud K.; Hamzah, Baharuddin
Jurnal Akademika Kimia Vol 3, No 4 (2014)
Publisher : Universitas Tadulako

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Abstract

Snowball throwing learning model is a modification of aquastion technique. This technique is focused on the ability to formulate questions which are combined in a game called snowball throwing. SMILES is a simple chemical notation comprehensive where the scructures of molecules can be found by using ASCII character which representing atom and bond symbol. The study aim is to determine the influence of snowball throwing assisted learning model SMILES code on hydrocarbon material to the learning outcomes of students clas XI in SMA Negeri 5 Palu. This study is experimental with pretest and posttest control group design, in which the samples are students of class XI IPA 2 (n=33) as experimental group while students of clas XI IPA 4 (n=32) as control group. The testing data used t-test statistical analysis one side (right) with pre-requisite test, normality test and homogeneity. The result of data analysis are the score of X1 experiment class is 73.81 with standard deviation is 8.19 while score of X2 control group is 65 with standard deviation is 14.36. Based on testing hypothesis result that tcounted>ttable is 3.05 > 1.67 with significance level 0.05 and confidence level = 63. The results show that H0 is rejected and H1 is accepted then it is concluded that the application of Snowball Throwing assisted learning model SMILES code on hydrocarbon material positively influence to the learning outcomes of students class XI in SMA Negeri 5 Palu.
Biocharcoal Dari Kulit Kakao (Theobroma cacao L)Untuk Mengadsorpsi Ion Logam Timbal Pb Podala, Katherina; Walanda, Daud K.; Napitupulu, Mery
Jurnal Akademika Kimia Vol 4, No 3 (2015)
Publisher : Universitas Tadulako

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Abstract

Cacao is a commodity crop growth in the plantation farmers, particularly in Central Sulawesi. Processed of the cocoa fruits are mainly as the food products. Furthermore, the cocoa bark just become rubbish. This study aims to utilize the waste of cocoa bark to be used as biocharcoal to adsorb lead metal ions. The method used was spectrophotometry, where the lead ions concentration absorbed was measured using a Spectrodirect spectrophotometer. The results showed that at the optimum contact time 90 minutes, the lead ion capacity adsorption was 97% and the lead weight adsorbed was 25.26 mg/g. The optimum weight of 60 mg, where the lead ions capacity adsorption was 96.88% and the lead weight adsorbed was 25.22 mg/g. The optimum adsorption capacity was 40 ppm, where the lead ions adsorption obtained was 99.61% and the lead weight adsorbed was 10.84 mg/g.
Analisis Kalium, Kalsium Dan Natrium Dalam Buah Merah (Pandanus baccari) Asal Kabupaten Poso Sebagai Alternatif Peluruh Batu Ginjal Yulianti, Iluh Devi; Walanda, Daud K.; Said, Irwan
Jurnal Akademika Kimia Vol 4, No 1 (2015)
Publisher : Universitas Tadulako

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Abstract

Red fruit (pandanus baccari) founded in Poso District was not familiar by many people. Red fruit contains chemicals that can be used as a traditional medicine for a wide variety of treatments. The purposes of this study were to analyze the content of potassium, calcium, and sodium in the extract of red fruit, and the solubility of calcium in the extract. Concentration of the extract was varied to 1%, 2%. 4%, and 6% to test the solubility of the calcium. Solubility of calcium in the extract of red fruit was determined by using atomic absorption spectrophotometer (AAS). The results showed that the extract of red fruit contained 30.35 ppm, 58.24 ppm, and 50.00 ppm of potassium, calcium, and sodium, respectively. Results of the solubility test of calcium in the extract showed that higher the concentration affected to the greater solubility. This can be seen from the difference between the lowest concentrations to the highest concentration in a row at 29.446 ppm, to 78.856 ppm, to 189.446, to 285.016 ppm. Thus it can be concluded that the extract of red fruit was possible to dissolve kidney stones.
Biocharcoal dari Biji Salak (Salacca edulis) sebagai Adsorben Terhadap Kromium Pongenda, Rudy Christiyanto; Napitupulu, Mery; Walanda, Daud K.
Jurnal Akademika Kimia Vol 4, No 2 (2015)
Publisher : Universitas Tadulako

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Abstract

Salak, snake skin fruit, is one of many kind fruit that is much preferred by people because its taste is sweet, crunchy and because it has a high nutrient content and have good prospects for cultivated. During this time, only flesh fruit of salak are utilized and the seed become waste. Therefore, it has been done a research about biocharcoal of salak seed (salacca edulis) as an absorbent for chromium. The method used in this study was a laboratory experiment using salak seeds biocharcoal as the adsorbent for chromium, concentration of absorbed chromium was measured by using a spectrodirect spectrophotometer. The results showed that the optimum time for adsorption of metal ion chromium obtained was 60 minutes with the absorption efficiency of 99.67%, while the optimum weight for absorption of metal ion chromium obtained was 80 mg with the absorption efficiency of 99.70% and the optimum concentration for absorption of metal ion chromium was 80 ppm with the absorption efficiency of 99.77%.
Biocharcoal dari Serbuk Gergaji Kayu Cempaka (Elmerrillia ovalis Miq) serta Daya Adsorpsinya pada Zink dan Tembaga Susilawati, Niluh Eka; Walanda, Daud K.; Napitupulu, Mery
Jurnal Akademika Kimia Vol 4, No 2 (2015)
Publisher : Universitas Tadulako

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Abstract

Cempaka wood is a typical wood in Sulawesi Island and Maluku archipelago. This wood can be used for wood industry particularly for the manufacture of furniture. However, not only furniture can be produced from the wood but also the sawdust as the waste. This research utilized the sawdust of cempaka wood as biocharcoal to adsorb zinc and copper ions included in liquid organic fertilizer complement based on variation of weight and concentration of biocharcoal. The method used in this study was the spectrophotometry spectroDirect with sawdust of cempaka wood as the adsorbent. The results showed the characteristic of water content of biocharcoal was 4.05% while ash content was 7.75%. The optimum weight of biocharcoal to adsorb zinc ions was 40 mg with the adsorption capacity of 19.97 mg/g while for copper ions was 60 mg with the adsorption capacity of 16.16 mg/g. The optimum concentration of zinc and copper ions than can be adsorbed was 60 ppm with the adsorption capacity of 11.80 mg/g for copper ion and 9.29 mg/g for zinc ion.
Pemanfaatan Ampas Tahu Sebagai Bahan Baku Pembuatan Biodiesel Trisnawati, Trisnawati; Walanda, Daud K.; Said, Irwan
Jurnal Akademika Kimia Vol 5, No 3 (2016)
Publisher : Universitas Tadulako

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Abstract

Biodiesel is an alternative raw material for fuel of diesel motor made from vegetable oil. This study attempted to utilize tofu dregs as raw material for biodiesel. This study aimed to determine the yield of biodiesel produced and the content of methyl esters in the biodiesel yield, and to analyze the quality of biodiesel produced based on Indonesian national standard (SNI). This study consisted of four stages: the provision of samples, pre-treatment, esterification and transesterification, and analysis of the quality of biodiesel produced which include the density at 15 °C, the viscosity at 40 °C, and the moisture content. The results showed that the yield of biodiesel was 4.01%, and the content of methyl ester shown by larger Rf (0.87) using eluent of hexane:diethylether:formic acid. Results of the analysis of biodiesel quality obtained the density at 15°C was 864 kg/m3, the viscosity at 40 °C was 2.57 mm2/s, and the water content was 4%. Based on the parameters ofthe density at 15 °C and the viscosity at 40 °C, the product of biodiesel met the requirements of SNI, while in term of the water content the product did not meet the requirements of SNI.
PENENTUAN KADAR KALIUM (K) DAN KALSIUM (Ca) DALAM LABU SIAM (Sechium Edule) SERTA PENGARUH TEMPAT TUMBUHNYA (Determination of Potassium (K) and Calcium (Ca) Content in Chayote (Sechium Edule) and The Effects With its Growth Soil) Cicik Fitriani, Ni Luh; Walanda, Daud K; Rahman, Nurdin
Jurnal Akademika Kimia Vol 1, No 4 (2012)
Publisher : Universitas Tadulako

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Abstract

Chayote (sechiumeaite) is an alternative source of vegetable which is consumed largely by the community. For that reason, the research was conducted to determine the content of potassium (K) and calcium (Ca) as wll as its relation to the growth soil. The method of this research is laboratory experiments by using atomic absorption spectrometry. The result shows that the content of potassium in Palolo’s chayote meat is 134.35 mg/100 g, skin and fruit meat is 269.10 mg/100 g, and in the ground is 34.02 mg/100 g. However, in Kebun Kopi’s pumpkin, the content of potassium (K) is 177.42 mg/100 g in its fruit meat, 298.35 mg/100 g in its skin and fruit meat, and 88.02 mg/100 g in the soil. On the other hands the content of calcium obtained as follows: in Palolo’s chayote meat is 38.53 mg/100 g, in the skin and fruit meat is 55.865 mg/100 g, and in the soil is 32.72 mg/100 g. In the area of Kebun Kopi’s chayote meat is 20.535mg/100 g, in the skin and fruit meat is 30.605 mg/100 g, and in the soil is 7.682 mg/100 g. Therefore, the content of potassium and calcium obtained is higher than in the literature.
Co-Authors AA Sudharmawan, AA Afadil Alep, Boni Alizah, Nur Almahdali, Khafifah Amalia, Maryam Anang Wahid M.Diah Arwansyah Arwansyah Baharuddin Hamzah Baloga, Hendra Bau Ratu Berlin, I Dewa Gede Darsikin Darsikin Delviana Melego Detris Poba Dewi, Evie Kurnia Maya Dewijayanti, Putu W. Djahir, Ahmad Rifaldi Djulia Onggo Eka Dewi Ellak I. von Nagy-Felsobuki Emi Sulmeni Finta Amalinda Finta Amalinda Fitriani Fitriani Fitriani, Eva Geoffrey A. Lawrance Hasmawati Hasmawati I Ketut Suada I Komang Jati Purnawan I Komang werdhiana I W. A. Wirawan Irwan Irwan Irwan Said Ismail Ismail Kasmudin Mustapa Kusuma, I Gede Yoga Nata Leonardo Leonardo Marungkil Pasaribu Mery Napitupulu Miryam B. Kalase Mohammad Jamhari Muhammad Agus Muljanto Mustakim, Sartika Nakazawa, Koyomi Napitupulu*, Mery Napitupulu, Nurasyah D Ni Luh Cicik Fitriani Novianti Patiung Nur A. O. Buhang Nurasyah Dewi Napitupulu Nurasyah Dewi Napitupulu Nurdin Rahman Nurhikma, Nurhikma Poba, Detris Podala, Katherina Pongenda, Rudy Christiyanto Purnama Ningsih Rahma, Sri Ratman Ratman Rimah Juwita Robert C. Burns Rukmawati Rukmawati Ryka Marina Walanda Setiawan, I Ketut Ardi Siang Tandi Gonggo Siang Tandi Gonggo Siti Nuryanti Sitti Aminah Sitti Rahmawati Solfarina, Solfarina Sri Hastuti Virgianti Pulukadang Sri Mulyani Sabang Sri Mulyani Sabang Suhartini Musa Supriadi Supriadi Susilawati, Niluh Eka Tahril Taslima Tiara Maharani, Tiara Tiwow, Vanny M A Trisnawati Trisnawati Tudjuka, Mora Delfita Uswatun Hasanah Wagiman, Saumadin Walanda, Ryka M Yeyet Sri Rahmi Yuli Nurmayanti Yulianti, Iluh Devi