Judul: Zat Ekstraktif Kayu Gliricidia sepium, Calliandra calothyrsus, dan Leucaena leucocephala serta Pengaruhnya terhadap Peningkatan Nilai Kalor Biomassa
Abstrak: Zat ekstraktif kayu merupakan komponen kimia kayu yang memiliki nilai kalor paling tinggi dibandingkan dengan komponen kimia kayu lainnya. Kadar dan jenis zat ekstraktif kayu beragam antar jenis, pada jenis yang sama, bagian pohon, dan bagian kayu, serta dapat berpengaruh terhadap sifat dan penggunaan kayu. Penelitian ini bertujuan untuk mengidentifikasi zat ekstraktif tiga jenis kayu yaitu gamal (Gliricidia sepium Jacq.), kaliandra merah (Calliandra calothyrsus Meissn.) dan lamtoro (Leucaena leucocephala Lam.) yang berpengaruh terhadap nilai kalor. Pengaruh zat ekstraktif terhadap nilai kalor kayu diuji melalui pengukuran nilai kalor sampel kayu sebelum dan setelah diekstraksi dengan pelarut etanol-benzena (1:2). Pengaruh zat ekstraktif terhadap nilai kalor dibuktikan dengan mengukur perubahan nilai kalor biomassa sawit setelah penambahan zat ekstraktif. Identifikasi kelompok zat ekstraktif yang diduga berpengaruh terhadap nilai kalor dianalisis melalui analisis fitokimia kualitatif dan LC-MS/MS. Hasil penelitian menunjukkan bahwa nilai kalor ketiga jenis kayu yang diekstraksi dengan etanol-benzena (1:2) menurun 2,62-6,70%. Penambahan zat ekstraktif ketiga jenis kayu pada biomassa sawit sebanyak 5% meningkatkan nilai kalor sebesar 5,86-10,33%. Hal tersebut mengkonfirmasi bahwa zat ekstraktif terlarut etanol-benzena (1:2) berpengaruh positif terhadap nilai kalor biomassa. Hasil analisis LC-MS/MS terhadap zat ekstraktif yang berpengaruh paling tinggi (zat ekstraktif kulit kayu gamal terlarut n-heksana) menunjukkan bahwa senyawa dominan yang teridentifikasi adalah terpenoid, yang merupakan kelompok zat ekstraktif bersifat non-polar., Wood extractive is a chemical component of wood with a high calorific value. The content and types of wood extractives vary between species, within the same species, tree parts, and wood parts, affecting the properties and utilization of wood. This study aims to identify extractives of three species of wood, namely Gliricidia sepium Jacq., Calliandra calothyrsus Meissn. and Leucaena leucocephala Lam., affecting the calorific value. The effect of extractives on the calorific value of wood was tested by measuring wood samples before and after extraction using ethanol-benzene solvent (1:2). The effect of extractives was confirmed by measuring the calorific value of oil palm biomass to which extractives were added. Furthermore, extractives with the highest effect were analyzed through qualitative phytochemical analysis and LC-MS/MS. The results showed that the calorific value of three wood species extracted by ethanol benzene (1:2) decreased 2.62 to 6.70%. The addition of extractives to the oil palm biomass as much as 5% increased the calorific value by 5.86-10.33%. This phenomenom confirms that the ethanol-benzene (1:2) soluble extractive has a positive effect on the calorific value of the biomass. LC-MS/MS analysis on extractives with a significant effect (n-hexane soluble gamal bark extracts) showed that the dominant compound identified were terpenoids which are a group of non-polar extractives.
Keyword: Calliandra calothrysus, Gliricidia sepium, Leucaena leucocephala, oil palm biomass, proximate analysis

Judul: Pengaruh Zat Ekstraktif Kayu Manglid (Magnolia Sumatrana Miq.) terhadap Nilai Kalor Batang Sawit
Abstrak: Zat ekstraktif merupakan komponen kimia dalam kayu yang mudah dilarutkan menggunakan pelarut polar, maupun nonpolar. Walaupun secara kuantitatif kandungan zat ekstraktif relatif kecil tetapi mempunyai peranan yang penting terhadap sifat kayu dan pengolahanya, salah satunya adalah meningkatkan nilai kalor kayu. Penelitian ini bertujuan untuk mengetahui pengaruh zat ekstraktif kayu manglid terhadap peningkatan nilai kalor biomassa sawit. Serbuk kayu manglid dimaserasi dengan menggunakan pelarut dengan polaritas yang berbeda yaitu n-heksana, etil eter, etil asetat, dan aseton. Selanjutnya masing-masing fraksi yang dihasilkan ditambahkan ke biomassa sawit dengan konsentrasi 0%, 2%, 4%, 6%, dan 8%, dan diukur nilai kalornya. Hasil penelitian menunjukan bahwa kadar ekstraktif yang dihasilkan bervariasi antara 0,27% - 0,99%, sedangkan nilai kalor yang dihasilkan 3580 – 3971 kkal/kg. Hasil analisis proksimat menghasilkan kadar air 11,27% - 15,59%, kadar abu 2,48% - 3,08, kadar zat terbang 78,08% - 80,16%, dan kadar karbon terikat 16,92% - 18,79%. Dari penelitian ini dapat disimpulkan bahwa penambahan fraksi n-heksana meningkatkan nilai kalor biomassa sawit tertinggi. Wood extractive substances are chemical components that can be easily dissolved using polar and nonpolar compounds. Although the quantity of extractives is relatively small, it has an important role in the properties of wood and its processing, one of which is increasing the calorific value of wood. The objectives of this study is to analyze the effect of manglid wood extractives to increase caloric value on oil palm biomass. Manglid wood was macerated using n-hexane, ethyl ether, ethyl acetate, and acetone as solvents with different polarities. Furthermore, each fraction was added to the oil palm biomass with concentrations of 0%, 2%, 4%, 6%, and 8% and the calorific value was measured. The results show that the extractive content produced varied between 0.27% - 0.99%, while the calorific value is 3580 - 3971 kcal/kg. Proximate analysis show that moisture content range from 11.27% to 15.59%, ash content range from 2.48% to 3.08%, volatile matter content range from 78.08 to 80.16%, and bound carbon content range from 16.92% to 18 ,79%. From this study, it is concluded that the addition of the n-hexane fraction increased the calorific value of the oil palm biomass.
Keyword: oil palm biomass, oil palm biomass, caloric value, wood extractive, manglid wood, proximate analysis

Judul: Implementation of Spatio-Temporal Change Query in Relational Database.
Abstrak: Geographic object changes in various views. Object changes are recorded using a model of static storage. No historical connection between old version data and new version data has been built. For that, a storage model of spatio-temporal queries that can analyze spatio-temporal changes has been developed. The object changes the geometry are grouped according to the taxonomy of Spatio-Temporal Pattern Change. This research has been able to apply the query patterns change including born, expand, merge, contract, split, normal and die. This query based on geometric (area) changes. The implementation of spatio-temporal change queries represents an object changes continuously with easy, change detection is done by comparing two versions of data. Keyword: spatio-temporal change query, spatio-temporal change pattern.
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