CO2 FLUX IN INDONESIAN WATER DETERMINED BY SATELLITE DATA

The oceans was considered to be a major sink for CO2. The improving of quantitative and qualitative description about the ability of sea in uptaking or emitting CO2 is a great scientific concern in meteorological and climatological science. Measurement of the ability of sea in uptake or emitting CO2 could determined by measuring the CO2 exchange coefficient on sea interface and the measuring the different partial pressure of CO2 between the air and sea. In this study, CO2 flux distribution of Indonesian waters in 2007 to 2009 was computed using monthly CO2 exchange and the different partial pressure of CO2 estimated from wind speed, salinity, SST, and sea characteristic, which were obtained from satellite data. The carbon dioxide flux thus was estimated and discussed by two different designs of transfer velocity (k), of Wanninkhof (1992), kW92 relationship and by Nightingale et al. (2000), kN, relationship. The result indicated that generally, Indonesian water was emitting the CO2 to the air. Average CO2 emitting from sea to the air for recent year in 2007 to 2009 are 3.80 (mol m-2year-1) and 2.85 (mol m-2year-1) with kW92 relationship and kN relationship calculation, respectively. The total average CO2 emission from sea to the air in 2007 to 2009 for the Indonesian waters areas are 0.15 (PgC year-1) and 0.12 (PgC year-1) based on kW92 relationship and kN relationship calculations, respectively. Keywords: CO2 flux, salinity, SST, sink and sources of CO2

Theoretical and experimental investigations of graphitic and crystalline carbon nitrides

Solid-state carbon nitride materials are useful in a number of areas in industry, ranging from heat retardation, photocatalysis, electrochemistry, as well as the potential to form a new super hard material to rival diamond. The flexible nature of the chemical bonding and environment of C and N atoms in a carbon nitride system gives rise to wide structural diversity, which present challenges in characterisation of the material. Theoretical modeling for such a versatile system is an essential part of scientific research. Quantum mechanical computational methods are employed to study carbon nitride materials in dense sp3 bonded and planar polymeric graphitic phases. The computer codes used for this study are CRYSTAL and CASTEP, both based on DFT. Synthesis of dense and graphitic carbon nitride materials, using ionothermal and thermal methods were also conducted towards part of this research. The results from each theoretically calculated investigation in this thesis are compared with experimental data, to guide the understanding of the experimental results for the system under study. Experimentally synthesised and recovered carbon nitride material, with defective wurtzite structure and C2N3H stoichiometry, was investigated for its stability over a range of pressures. Three possible C2N3H phases arising from different proton arrangements were modeled to determine the most stable arrangement. A metastable C2N3H phase was detected experimentally; an ab initio structure prediction method was employed, which identified a structure that complied with experimental observations. CASTEP was tested and used to calculate NMR chemical shifts for 13C and 15N atoms for a number of carbon nitride materials. Predictions were focused on determining the atom connectivity and structural topology for thermal synthetic methods that yielded dense and graphitic carbon nitride solid‐state materials. Calculated NMR chemical shifts were also employed in a collaborative study to guide the understanding of planetary tholins, formed in Titan’s atmosphere

APLIKASI SISTEM INFORMASI GEOGRAFI (SIG) BERBASIS DATA RASTER UNTUK PENGKELASAN KEMAMPUAN LAHAN DI PROVINSI BALI DENGAN METODE NILAI PIKSEL PEMBEDA = (Application of Geographic Information System (GIS) based raster data

Penggunaan teknologi seperti SIG sangat baik untuk mengelompokkan data keruangan lahan berdasarkan faktor potensi dan penghambat penggunaannya. Dengan mengimprovisasi metode tumpang susun diharapkan mampu mempercepat proses studi tentang pengkelasan kemampuan lahan. Tujuan penelitian ini adalah pengaplikasian SIG berbasis data raster untuk memetakan kelas kemampuan lahan di Provinsi Bali dengan menggunakan metode "nilai piksel pembeda". Hasil penelitian menunjukkan bahwa penggunaan SIG dapat memperlihatkan sebaran kelas kemampuan lahan yang heterogen dan kompleks sehingga mcmperjelas informasi lahan pada satuan unit lahan yang sempit. Selain itu penggunaan metode ini juga membantu mempercepat proses tumpang susun\u27 dan query data. Kelas kemampuan lahan di Provinsi Bali dapat dikelompokkan menjadi 8 kelas, dari kelas I sampai kelas VIII. Sebaran kelas kemampuan lahannya didominasi oleh lahan dengan kelas VI, VII dan VIII yaitu seluas 50,7% dari luas Provinsi Bali. Kabupatcn Buleleng, Jembrana, dan Karangasem berturut-turut merupakan daerah-daerah tcrluas- yang mcmiliki kemampuan lahan kelas VIII. Daerah-daerah tersebut harus lebih instensif dalam menjaga lahan-lahan berkelas VIII agar tidak beralih fungsi dari lahan hutan menjadi lahan non hutan

Pemetaan kondisi hutan mangrove di kawasan pesisir Selat Madura dengan pendekatan Mangrove Health Index memanfaatkan citra satelit Sentinel-2

Abstrak. Pemetaan dan pemantauan kondisi hutan mangrove diperlukan untuk rehabilitasi dan konservasi lingkungan. Mangrove Health Index (MHI) menggunakan analisis citra satelit merupakan pendekatan baru yang bisa digunakan untuk mengetahui kualitas lingkungan ekosistem hutan mangrove. Penelitian ini bertujuan untuk untuk mengetahui struktur komunitas hutan mangrove dan melakukan analisis spasial-temporal MHI di kawasan pesisir Surabaya dan Sidoarjo menggunakan citra satelit. Data yang digunakan untuk analisis struktur komunitas mangrove pada penelitian ini adalah hasil pengamatan lapang di 10 transek. Untuk analisis MHI menggunakan citra Sentinel 2 perekaman tahun 2015, 2018, 2021. Hasil analisis menunjukkan bahwa spesies mangrove yang paling dominan di lokasi penelitian adalah Avicennia marina. Analisis citra satelit mendeteksi pertambahan luas mangrove yang signifikan dari tahun 2015 hingga 2021 yaitu lebih dari 500 Ha. Berdasarkan analisis MHI, terjadi perubahan positif dari kondisi hutan mangrove dominansi buruk (MHI 66,68%). Pertambahan luas hutan mangrove diiringi dengan perbaikan kondisi ekosistem dengan indikator meningkatnya MHI.Abstract. Mapping and monitoring the condition of mangrove forests is needed for environmental rehabilitation and conservation. Mangrove Health Index (MHI) using satellite image analysis is a new approach that can be used to determine the environmental quality of mangrove forest ecosystems. This study aims to determine the structure of the mangrove forest community and conduct a spatial and temporal MHI analysis in the coastal areas of Surabaya and Sidoarjo. The data used in this study were the results of field observations on 10 transects. MHI analysis using Sentinel 2 imagery recorded in 2015, 2018, 2021. The results of the analysis show that the most dominant mangrove species in the research location is Avicennia marina. Analysis of satellite imagery detects a significant increase in mangrove area from 2015 to 2021, which is more than 500 Ha. Based on the MHI analysis, there was a positive change from poor dominant mangrove forest conditions (MHI 66.68%). The increase in the area of mangrove forests is accompanied by improvements in ecosystem conditions with indicators of increasing MHI.

Pengaruh Lebar Pondasi Dan Jumlah Lapis Perkuatan Geogrid Terhadap Daya Dukung Pondasi Menerus Pada Pemodelan Lereng Pasir Dengan Kemiringan 46o

Longsor sering kerap terjadi, yang utamanya sering terjadi pada daerah dataran tinngi dan lembah. Dengan kondisi seperti ini, cukup banyak masyarakat khususnya yang berada pada dataran tinggi membuat pemukiman di lembah maupun di lereng yang sewaktu-waktu dapat terjadi kelongsoran. Untuk mencegah kelongsoran yang akan terjadi yaitu perlu digunakan perkuatan pada tanah, contohnya yaitu dengan perkuatan geogrid. Penelitian dilakukan dengan menggunakan uji model lereng pada tanah pasir dengan kepadatan relatif 85%. Variasi yang digunakan yaitu variasi lebar pondasi antara lain 4 cm, 6cm dan 8 cm dan variasi jumlah lapis perkuatan geogrid yaitu antara lain 1 lapis, 2 lapis dan 3 lapis. Dalam penelitian ini, lereng terbentuk dalam 7 lapis tanah dengan tinggi pada setiap lapisan yaitu 10 cm. Berdasarkan pada penelitian ini didapatkan hasil yaitu bertambahnya jumlah lapis perkuatan geogrid lebih dominan daripada bertambahnya lebar pondasi terhadap peningkatan daya dukung pada lereng

Efficacy and economics of different herbicides in aerobic rice system

Aerobic rice system, the most promising irrigation water saving rice production technology, is highly impeded by severe weed pressure. Weed control through the use of same herbicide causes development of herbicide resistant weed biotypes and serious problem in weed management. This study was aimed at finding out herbicides with different mode of actions to suggest effective weed control herbicide technology in aerobic rice system. This study was conducted at Malaysian Agricultural Research and Development Institute (MARDI), Seberang Perai Station, Penang, Malaysia during off season 2008 (April – July 2008) and main season 2008-2009 (November 2008 – February 2009) to evaluate fourteen and eight combinations of different locally available herbicides, in the off season and main seasons, respectively. A weed free control and a weedy check treatment were also included in the both trials. The trial used a RCB design with three replications in the off season and four replications in the main season, respectively. Twenty one (21) weed species were found in the aerobic rice field but two species (Eleusine indica and Digitaria ascendens) appeared as dominant. Based on the weed control efficiency, weed index values and net benefit from economic analysis, it appeared that the herbicide combinations such as Propanil/Benthiocarb fb Bentazone/MCPA or Cyhalofopbutyl+ Bensulfuron fb Bentazone/MCPA or Pendimethalin fb Cyhalofop-butyl+ Bensulfuron fb Bentazone/MCPA or Pretilachlor+Pendimethalin fb Bentazone/MCPA could be the possible alternative options for effective and economic weed control in rice under aerobic system towards avoiding development of herbicide resistance in weed. Manual weeding is not at all cost-effective. The selected herbicide combinations could be used in rotation for sustainable weed management and to run the aerobic rice system as a profitable business venture.Key words: Herbicide combination, summed dominance ratio, weed control efficiency, weed index, rice yiel

Evaluation of pressed shredded empty fruit bunch (EFB)-palm oil mill effluent (POME) anaerobic sludge based compost using Fourier transform infrared (FTIR) and nuclear magnetic resonance (NMR) analysis

Pressed-shredded empty fruit bunches (EFB) and palm oil mill effluent (POME) anaerobic sludge from a 500 m3 closed anaerobic digester system was utilized for the co-composting treatment. Scanning electron microscopy (SEM) analysis showed that the shredding-pressing treatment on EFB gave better results in removing the debris and silica bodies as compared to only shredding treatment. However, similar characteristics were detected in both physically-treated EFB samples by Fourier transform infrared (FTIR) analysis, mainly in the regions of 900 to 1740 and 2800 to 3400 cm-1. After the anaerobic digestion of fresh raw POME, the protein origin (Amide I) band appeared in the POME anaerobic sludge. Besides, the band intensities at 2925 and 2855 cm-1 which attributed to the composition of fat and lipid was decreased. The maturity of the composting material after 40 days of treatment was detected by the appearance of the nitrate band at 1376 cm-1 and the results corresponded to the final C/N ratio of 12.4. Solid state 13C CP/MAS nuclear magnetic resonance (NMR) was also used to reveal the characteristic changes of pressed-shredded EFB-POME anaerobic sludge based compost.Key words: Empty fruit bunch, palm oil mill effluent, compost

Improving The Critical Thinking Ability of Students to Solve Mathematical Task

This study aims to describe students' critical thinking skills before and after the learning process. Analysis of critical thinking skills in this study based on components of critical thinking evaluation, inferences, explanations, and self-regulation. This type of research is descriptive research with a qualitative approach. The research subject consisted of 2 students with low critical thinking abilities based on task 1 given at the beginning of learning, besides that good communication was also one of the subject selection criteria. The results of the analysis showed that both research subjects SS and FT experienced an increase in their critical thinking abilities, this was evident from each indicator critical thinking evaluation, inferences, explanation, and self-regulation. In each indicator of critical thinking, the research subject is able to demonstrate the ability to do evaluation, inferences, explanation, and self-regulation, this is certainly very different from the initial conditions of research subjects where they have not been able to do evaluations, inferences, explanation well. One of the things that allows an increase in critical thinking skills is the subject of teaching and learning activities, namely by giving task that require students to practice their critical thinking skills

THE VALUES OF ISLAMIC EDUCATION IN THE STORY OF IBRAHIM P.B.U.H (Analysis Of Chapter Al-An'am Verses 74-81 And Chapter Al-Anbiyâ 51-70).

Abstrak: The purpose of this study is to examine the content of Islamic education values in the story of Prophet Ibrahim As in chapter Al-an'am verses 74 to 81 and chapter Al-Anbiyâ verses 51 to 70. Both stories have a thematic relationship from the message they carry. If at chapter Al-an'am verses 74-81, Prophet Ibrahim p.b.u.h found the presence of God by observing the signs in nature then in chapter Al-Anbiyâ verse 51-70, the prophet Ibrahim p.b.u.h conveyed instructions about the presence of God to his people by means of discussion to his people. The methodology used in the study is the Library Study Method. This research belongs to the literature study using the method of content analysis with the Tahlili Method. There is also the research method used is the method of interpretation of the maudhu'i, namely the method of interpreting the Qur'an thematically by summarizing the verses of the Koran that are relevant to the values of education to be studied. The data sources used in this study are the Qur'anic translation of the Ministry of Religion of the Republic of Indonesia, the exegesis of Ibn Kathir, the exegesis of Muhammad Quraiys Shihab al-Misbah, the exegesis of Muhammad Mutawalli Sya'rawi and the exegesis of Fi Zilal Quran sayyid qhutub. The results of this study show the values of Islamic education in the aspects of Aqidah, the story of Prophet Ibrahim p.b.u.h in the chapter Al-an'am verses 74-81 teaches the values of true Aqeedah as follows: 1. The value of Aqeedah. Almighty Allah will not have the "drowning" nature which means that he will not leave his creatures and supervising will always be there for his creatures, Allah will give guidance to His creatures, Allah is the Almighty so that Allah is not equal. 2. Moral values. Morals to Allah (habluminallah): if Allah gives instructions to his servant and answers prayers, then it is an obligation for His servants to accept His instructions and guidance and not obey them. While the values of Islamic education in the story of the prophet Ibrahim p.b.u.h in Al-Anbiyâ chapter verses 51-70, are as follows: 1. The value of Aqeedah, Idols are not worthy of being considered gods because they cannot protect themselves from being destroyed so how can idols protect the devotee. Idols cannot even tell who has destroyed him so that the idol itself cannot also guide his devotee, 2. The Value of Ukhuwah, Morals displayed in the story of Prophet Ibrahim p.b.u.h are noble morals both in the face of his infidel father and facing his people infidel He was not hostile to his father and even prayed for his father. He invited his people to dialogue in conveying the truth. The value of ukhuwah here is ukhuwah insaniyah, 3. The educational value of discussion, Prophet Ibrahim p.b.u.h in conveying the truth and rectifying the mistakes of his people in worship by means of dialogue using logic and persuasive style.Keywords: Chapter Al-An'am, Chapter Al-Anbiyâ, Prophet Ibrahim P.B.U.H, Values, Education, Aqidah, Akhlak, Ukhuwa