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"As a result of waterflooding, inorganic salt precipitation occurs in the different parts of an oil production system, thereby leading to damage of production equipment. Different parameters affect the kinetics of salt precipitation. Scale inhibitors are widely used to prevent inorganic salt formation. In this study, the effect of reservoir pressure, temperature, and mixing ratio of injection to formation water on calcium sulfate and barium sulfate precipitation was investigated. For this purpose, two different formation waters and one injection water were used. In addition, the effect of temperature and mixing ratio on inhibition performance was studied. Four different existing industrial scale inhibitors and one new scale inhibitor were used. The performance of the scale inhibitors was determined under static and dynamic conditions. Results of the study showed that calcium sulfate precipitation increased with an increase in temperature and a decrease in pressure. Barium sulfate precipitation was found to increase with a decrease in the temperature. The effect of pressure on barium sulfate formation was negligible. The developed scale inhibitor showed the highest performance for the prevention of calcium sulfate and barium sulfate formation. A change in temperature from 60°C to 120°C reduced the inhibitor performance by 3%. In the cases of calcium sulfate and barium sulfate, the minimum performance of the scale inhibitor was observed when the mixing ratios of injection to formation waters were 60:40 and 50:50, respectively."

"As a result ofwaterflooding, inorganic salt precipitation occurs in the different parts of anoil production system, thereby leading to damage of production equipment.Different parameters affect the kinetics of salt precipitation. Scaleinhibitors are widely used to prevent inorganic salt formation. In this study,the effect of reservoir pressure, temperature, and mixing ratio of injection toformation water on calcium sulfate and barium sulfate precipitation wasinvestigated. For this purpose, two different formation waters and oneinjection water were used. In addition, the effect of temperature and mixingratio on inhibition performance was studied. Four different existing industrialscale inhibitors and one new scale inhibitor were used. The performance of thescale inhibitors was determined under static and dynamic conditions. Results ofthe study showed that calcium sulfate precipitation increased with an increasein temperature and a decrease in pressure. Barium sulfate precipitation wasfound to increase with a decrease in the temperature. The effect of pressure onbarium sulfate formation was negligible. The developed scale inhibitor showedthe highest performance for the prevention of calcium sulfate and bariumsulfate formation. A change in temperature from 60°C to 120°C reduced theinhibitor performance by 3%. In the cases of calcium sulfate and bariumsulfate, the minimum performance of the scale inhibitor was observed when themixing ratios of injection to formation waters were 60:40 and 50:50,respectively."

"Estuaries, which are rich in nutrient, act as a habitat to some aquatic lives, including mangroves. Human-induced activities such as dredging and shoreline development influence estuarine dynamics which includes mixing process. This will further affect estuarine salinity and adversely affect the aquatic life. A laboratory investigation was conducted in a flume to observe the mixing in a salt-wedge estuary. Three conditions were studied, i.e. mixing in ordinary estuary, mixing in an estuary with a presence of smaller deep channel and mixing in an estuary with a presence of resisting structures along the channel banks. Freshwater was run from one end of the channel, overflowing a weir at the other end, while salt water was introduced at the base of the weir and intruded upstream as gravity current. Mixing in open channel occurs in longitudinal, vertical and transverse directions. The spatial and temporal salt-water intrusions were studied where the mixing patterns were visualized using red dye tracer. To have better understanding on the mixing process, salinity patterns are studied through the plotted isohalines. The spatial and temporal salinity profiles in the flume are also studied through plotted graphs. The results show that salinity differences occurred due to the interfacial mixing between saline and freshwater"

"Saat ini sumber cadangan litium di dunia >70% hadir dalam bentuk brine water. Serangkaian penelitian telah dilakukan terhadap brine water yang ditemukan pada mata air Gunung Panjang, Ciseeng, Bogor untuk mengetahui pengaruh proses elektrolisis terhadap rasio Mg/Li yang terkandung di dalam brine. Pada penelitian, dilakukan proses elektrolisis terhadap brine water dengan variasi tegangan sebesar 15 V dan 20 V diikuti oleh pemanfaatan jembatan garam selama 60 jam elektrolisis berlangsung. Jenis uji karakterisasi yang dilakukan terhadap hasil penelitian meliputi uji ICP-OES untuk filtrat yang dihasilkan selama proses elektrolisis, serta XRD dan SEM-EDS untuk residu yang dihasilkan pada tiap variabel dengan nilai Mg/Li terkecil. Berdasarkan analisis yang dilakukan, diketahui bahwa proses elektrolisis mampu mempengaruhi nilai Mg/Li pada brine seiring dengan bertambahnya waktu, serta peningkatan arus dan penggunaan dari jembatan garam selama proses elektrolisis dilakukan. Rasio Mg/Li terkecil yang diperoleh untuk masing – masing variabel sebesar 2,96; 3,37; 4,31 serta 6,01 dengan variabel 15 V jembatan garam menghasilkan nilai rasio Mg/Li terkecil. Data analisis XRD menunjukkan 5 senyawa padat yang terbentuk meliputi Mg(OH)2 (brucite), Ca(OH)2 (portlandite), KCl(sylvite), LiCl dan NaCl (halite).

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Currently, >70% of the world's lithium reserves come in the form of brine water. A series of studies have been conducted on brine water found in mata air Gunung Panjang, Ciseeng, Bogor to determine the effect of electrolysis process on the Mg/Li ratio contained in the brine. In the research, the electrolysis process was carried out on brine water with voltage variations of 15 V and 20 V followed by the utilization of salt bridges for 60 hours of electrolysis. The types of characterization tests carried out on the research results include ICP-OES tests for the filtrate produced during the electrolysis process, as well as XRD and SEM-EDS for the residue produced in each variable with the smallest Mg/Li value. Based on the analysis conducted, it is known that the electrolysis process affects the Mg/Li value in the brine as time increases, as well as the increase in current and the use of the salt bridge during the electrolysis process. The smallest Mg/Li ratio obtained for each variable was 2.96; 3.37; 4.31 and 6.01 with the 15 V salt bridge variable producing the smallest Mg/Li ratio value. XRD analysis data showed 5 solid compounds formed including Mg(OH)2 (brucite), Ca(OH)2 (portlandite), KCl (sylvite), LiCl and NaCl (halite)."

"Penelitian ini merupakan rangkaian dari proses pengolahan bijih nikel laterit hingga menjadi produk antara yakni mixed hydroxide precipitate (MHP) menggunakan proses hidrometalurgi. Penelitian ini bertujuan untuk mengurangi kandungan pengotor utama besi dan pengotor lainnya serta meningkatkan efisiensi kandungan elemen berharga seperti nikel dan kobalt. Sampel awal yang digunakan pada penelitian ini berbentuk pregnant leach solution (PLS). Selanjutnya, PLS akan dilakukan proses multistage iron removal dengan menggunakan kalsium karbonat (CaCO₃) dengan kadar 25% w/w, 15% w/w, dan 12,5% w/w pada masing-masing tahap. Kemudian sampel dipanaskan pada temperatur 90^oC selama 2, 1,5, dan 1 jam pada setiap tahap. Kemudian, penelitian dilanjutkan dengan melakukan presipitasi MHP pada sampel yang telah melewati multistage iron removal. Proses presipitasi MHP dilakukan dengan menggunakan reagen natrium hidroksida (NaOH) dengan konsentrasi 2,5M. Presipitasi dilakukan hingga mencapai pH 9 lalu dilanjutkan dengan pemanasan pada temperatur 90^oC selama 1 jam. Pada penelitian ini, ditemukan beberapa faktor yang menyebabkan tidak meningkatnya kadar nikel secara signifikan sehingga belum terbentuk produk yang diinginkan. Faktor tersebut diantaranya kadar pengotor lain seperti sulfur dan mangan yang masih cukup tinggi, ageing time yang terlalu lama, kecepatan titrasi yang terlalu tinggi, dan tingkat kejenuhan sampel yang tinggi. Hasil dari proses multistage iron removal menunjukkan bahwa terjadi pengurangan kandungan besi hingga 92% melalui pengujian ICP OES. Sementara itu, pada proses presipitasi MHP dihasilkan nikel dengan kandungan mencapai 18,83%.

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This research is a series of processing of lateritic nickel ore to become an intermediate product, namely mixed hydroxide precipitate (MHP) using a hydrometallurgical process. This research aims to reduce the content of the main impurities iron and other impurities and increase the efficiency of the content of valuable elements such as nickel and cobalt. The initial sample used in this study was in the form of pregnant leach solution (PLS). Furthermore, PLS will be carried out a multistage iron removal process using calcium carbonate (CaCO₃) with levels of 25% w/w, 15% w/w, and 12.5% w/w at each stage. Then the samples were heated at 90^oC for 2, 1.5, and 1 hour at each stage. Then, the research was continued by conducting MHP precipitation on samples that had undergone multistage iron removal. The MHP precipitation process was carried out using sodium hydroxide (NaOH) reagent with a concentration of 2.5M. Precipitation was carried out until it reached pH 9 and then followed by heating at 90^oC for 1 hour. In this study, several factors were found that caused the nickel content not to increase significantly so that the desired product had not been formed. These factors include the levels of other impurities such as sulfur and manganese which are still quite high, the aging time is too long, the titration speed is too high, and the sample saturation level is high. The results of the multistage iron removal process show that there is a reduction in the iron content of up to 92% through the ICP OES test. Meanwhile, the MHP precipitation process produces nickel with a content of up to 18.83%."

"ABSTRAKA cross sectional study to determine the salt consumption at household level was carried out in Sukabumi District. Two hundred households with children 1-5 years were selected randomly. This study consisted of interviews of the mothers, observation of iodized salt usage and analysis of the iodine content in iodized salt. The results showed that all households in the study area have used iodized salt but they were not aware that. they used iodized salt. The average salt consumption at household level was 4.8 gr per day per capita with majority iodine intake (71 %) less than 100 pg. Using lodometry test, 47 % of households had iodine content in iodized salt was less than 30 ppm. In general, all cooked food used salt except for rice as staple food, but not all of food prepared with salt were consumed by children 1-5 years. According to mothers' perception, the mother with better knowledge had higher percentages on using iodized salt and also had better educational level. These findings showed that the recommended iodine intake by WHO of 100-300 pg per day per capita was not fulfilled, mainly because of the low quality of iodized salt, as well as improper ways of salt storage and food preparations. Lack of knowledge due to low educational level of mother was worsening this condition."

"ABSTRACTDalam proses produksi biodiesel terbentuk komponen pengotor seperti Saturated Monoglycerides SMG yang akan terpresipitasi apabila biodiesel beroperasi pada suhu rendah. Hal ini disebabkan oleh tingginya Final Melting Temperature FMT atau titik lebur dari SMG dan akan membentuk endapan padat diatas Cloud Point CP. Penggunaan biodiesel yang dicampurkan dengan petroleum diesel BXX dengan rasio B10 10, B20 20, dan B30 30 akan meningkatkan proses presipitasi pada suhu rendah dan menyebabkan penyumbatan pada filter atau dispenser bahan bakar kendaraan. Penelitian ini bertujuan untuk mengetahui pengaruh variasi rasio pencampuran dan suhu terhadap laju perumbuhan presipitat. Hal diatas diteliti dengan menggunakan beaker test untuk mendapatkan jumlah presipitat yang terbentuk setiap harinya selama 2 minggu, dengan suhu penyimpanan 15oC, 20oC, 25oC, dan suhu ruang 30 - 33oC. Jumlah presipitat akan bertambah seiring dengan kenaikan persentase biodiesel dalam campuran. Semakin rendah suhu penyimpanan, presipitat yang terbentuk didalam campuran biodiesel dan petroleum diesel akan semakin meningkatDalam proses produksi biodiesel terbentuk komponen pengotor seperti Saturated Monoglycerides SMG yang akan terpresipitasi apabila biodiesel beroperasi pada suhu rendah. Hal ini disebabkan oleh tingginya Final Melting Temperature FMT atau titik lebur dari SMG dan akan membentuk endapan padat diatas Cloud Point CP. Penggunaan biodiesel yang dicampurkan dengan petroleum diesel BXX dengan rasio B10 10, B20 20, dan B30 30 akan meningkatkan proses presipitasi pada suhu rendah dan menyebabkan penyumbatan pada filter atau dispenser bahan bakar kendaraan. Penelitian ini bertujuan untuk mengetahui pengaruh variasi rasio pencampuran dan suhu terhadap laju perumbuhan presipitat. Hal diatas diteliti dengan menggunakan beaker test untuk mendapatkan jumlah presipitat yang terbentuk setiap harinya selama 2 minggu, dengan suhu penyimpanan 15oC, 20oC, 25oC, dan suhu ruang 30 - 33oC. Jumlah presipitat akan bertambah seiring dengan kenaikan persentase biodiesel dalam campuran. Semakin rendah suhu penyimpanan, presipitat yang terbentuk didalam campuran biodiesel dan petroleum diesel akan semakin meningkat.

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ABSTRACTIn the biodiesel production process, impurities such as Saturated Monoglycerides SMG that precipitate at low temperature are commonly formed. This is caused by high Final Melting Temperature FMT of SMG. Formation of solid deposits when it reach temperature above Cloud Point CP is then unavoidable under these conditions. The use of biodiesel petroleum blends BXX with biodiesel blend ratio of 10 B10, 20 B20 and 30 B30 accelerates precipation process which renders clogging on fuel filters. These works examined the effect of blend ratio and temperature on the precipitation rate. Investigation is carried out using beaker test to obtain the amount of precipitation formed everyday for 2 weeks storage time. BXX stored at 15oC, 20oC, 25oC, and room temperature 30 33oC in cooling chambers. The results indicates that as the biodiesel ratio in BXX become higher and the storage temperature become lower, the amount of precipitates formed will increase. "

"Studi diagnostik tes garam cepat dan titrasi garam terhadap kadar yodium dalam urin sebagai upaya monitonng program penanggulangan GAKY di Indonesia merupakan ana/isis lanjut Riskesdas 2007 sebagai baseline data kesehatan d1 Indonesia. Sampel dipilih secara purposive yakni rumah tangga dari 30 kabupatenlkota yang tercakup dalam suNey sebelumnya (SGY 2003). Hasil ana/isis menunjukkan ada hubungan antara titrasi garam dengan urin intake excretion (UIE) dengan kuat hubungan 7.3% dan hubungan tersebut dapat dije/askan sebesar 0,5%. Uji Chi-square menunjukkan ada perbedaan yang signifikan kadar UIE menu rut tes garam cepat (p=O, 000), dengan peningkatan faktor resiko temadap kandungan yodium dalam urin (OR= 1, 762). Demikian juga untuk kadar UIE menurut titrasi garam yang juga menunjukkan perbedaan yang signifikan (p=0,001 ; OR=1, 740). Tes Anova menunjukkan ada perbedaan yang signifikan kadar UtE menu rut titrasi garam (p=0,019). Mean UtE dengan titrasi cukup yodium = 274,73 meg dan kurang yodium=248,38 meg; sebaliknya tes garam cepat menunjukkan tidak ada perbedaan. Penggunaan tes garam cepat maupun titrasi garam memberikan hasil signifikan temadap UtE. Tes garam cepat memiliki nilai yang /ebih sensitif daripada titrasi garam, tetapi titrasi garam memiliki angka yang lebih spesifik. Namun demikian, penggunaan tes garam cepat secara ekonomis jauh lebih murah dan mudah dibandingkan titrasi garam. Sebagai rekomendasi, tes garam cepat bemubungan dengan U/E sehingga dapat digunakan untuk prediksi kadar UIE yang lebih murah dan mudah dilakukan. Penggunaan tes garam cepat untuk penilaian kadungan yodium garam di masyarakat cukup signifikan, sensitif serta efisien dibandingkan dengan uji titrasi, sehingga dapat direkomendasikan sebagai metode yang cukup ap/ikabel dimasa yang akan datang."

"Salt, is a potential vehicle and has extensively been used for delivery of iodine to the population, as an iodized salt. Many methods for assessing intake of salt have been applied in several studies in Indonesia, but all those methods were suspected to be relatively inaccurate. More precise method needed to define the amount of discretionary salt intake, which is salt added during cooking and at the table.Lithjum.marker technique is a relatively new method, has been established as a suitable, safe and biological reference for tracking the actual intake of individual salt. This method has been treated as a ?gold standard? method for assessing the discretionary salt intake. This result report deals with three methods: lithium-labeled salt technique, 24-hour salt recall and salt weighing, for assessing discretionary salt intake among children and mothers in an iodine deficient area of East Java-Indonesia.The research report has been organized under three major parts. The first part, the introduction, consists ofbackground, problem statement and rationale ofthe study, literature review, conceptual framework of research, objectives and variable and indicator matrix. Part two, the manuscript for publication to International Journal of Food Science and Nutrition. This part provides the abstract, introduction, subjects and methods, result, discussion, conclusion, and references. Part three is the last part of this report, the appendices, consists of questionnaires, detailed of the methodologies, detailed of the results, ethic application and ethical clearance, grand approval, references and curriculum vitae."

"Curah hujan adalah satu unsur cuaca yang memiliki pengaruh cukup besar terhadap berbagai sektor kehidupan manusia termasuk dalam sektor kelautan, khususnya terhadap produksi garam. Penambahan curah hujan di masa produksi garam berpotensi menimbulkan penurunan produksi, bahkan pada tingkat ekstrim dapat mengakibatkan kegagalan panen. Penelitian ini bertujuan untuk mengetahui pengaruh variabilitas curah hujan terhadap produksi garam sekaligus kesesuaian lahan produksi di Kabupaten Sumenep Jawa Timur dilihat dari jumlah rata-rata curah hujan tahunan, panjang musim kemarau dan jumlah maksimum hari tanpa hujan berturut-turut. Berdasarkan analisis statistik, variabilitas curah hujan, berkorelasi kuat dengan produktivitas garam di Kabupaten Sumenep Jawa Timur, terutama panjang musim kemarau. Sedangkan berdasarkan analisis spasial, desa sentra garam memiliki kesesuaian yang menengah sampai sangat tinggi. Hasil penelitian menyarankan pentingnya informasi panjang musim kemarau dalam informasi iklim kepada pelaku sektor garam.

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Rainfall is the weather-climate element that influences various sectors of human activities, such as the marine sector, particularly the salt industry when the production is done in the traditional way. The increase of rainfall will potentially decrease the productivity of salt, moreover at an extreme level, it can lead to total production failure.

This study aims to determine the effect of rainfall variability on salt production in Kabupaten Sumenep East Java based on parameters of average amount of annual rainfall, a length of the dry season and the maximum number of consecutive dry days/dry-spell.

Based on statistical analysis, the rainfall variability is strongly correlated with the fluctuation of salt productivity, especially a length of the dry season. The spatial analysis shows that the saltworks are located in appropriate areas which have supporting climate conditions. It is recommended that the climate information provides to salt production includes a length of dry season information."