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"ABSTRACTIonic liquids are considered as an ideal alternative to volatile organic solvents and chemical industries in the future, because they are non-volatile. Ionic liquids are also considered as new novel chemical agents and widely regarded as a greener alternative to many commonly used solvents. Ionic liquids have been studied for a wide range of synthetic applications and have attracted considerable interest for use as electrolytes in the areas of organic synthesis, catalysis, solar cell, fuel cells, electrodeposition and supercapacitors. However, some ionic liquids suffer from more or less somedrawbacks such as toxicity, preparation and high cost in the process for use. Most recently, three types of ionic liquids are attracted much attentions specifically traditional ionic liquid, protic ionic liquid and deep eutectic solvent, where their preparation, mechanism and limitation were differentiated. However, those liquids are having their own advantages and limitations based on applications. Traditional ionic liquid and protic ionic liquid are highly cost and toxic for applied engineering research, but they consist of micro-biphasic systems composed of ionic compounds whichhave more varieties in the applications. The deep eutectic solvent is very economic for large-scale possessing but there are only limited ionic mixtures to certain application such as electrochemistry."

"Indonesia merupakan negara yang memiliki kelembaban yang cukup tinggi dan cuaca yang cukup panas, oleh karena itu negara Indonesia membutuhkan alat pengering udara agar kelembaban dapat turun sampai titik nyaman untuk manusia. Sistem pengering udara lebih ramah lingkungan sebagai teknologi alternatif untuk proses penurunan kelembaban, terutama dalam kasus dengan muatan laten yang tinggi untuk menjaga kualitas udara. Teknologi ini lebih efisien di iklim panas dan lembab seperti Indonesia. Penelitian ini melakukan penyelidikan eksperimental untuk mengetahui rasio kelembapan terhadap udara untuk mengetahui karakteristik cairan ionik menggunakan alat pengering udara. Cairan ionik dalam percobaan ini akan melewati bilah kayu yang berfungsi sebagai alat penukar kalor, cairan ionik akan bersirkulasi selama kurang lebih dua jam. Eksperimen ini memvariasikan laju aliran cairan ionic dari 200 sampai 600 L/h dan didapatkan juga hasil rasio kelembaban yaitu -0.10 sampai -0.56 g/kg. Setiap kenaikan laju aliran besarannya juga akan semakin meningkat. Konsumsi energi di dunia meningkat setiap tahunnya, terutama dalam industri dan sektor transportasi. Konsumsi energi yang besar ini menghasilkan emisi karbon dioksida yang berbahaya bagi lingkungan dan kesehatan manusia. Salah satu cara untuk mengurangi konsumsi energi dan emisi karbon dioksida adalah dengan menggunakan sistem HVAC yang efisien.  Saat ini, banyak penelitian dilakukan untuk mencari solusi sistem HVAC yang lebih efisien. Salah satu solusi yang sedang dikembangkan adalah penggunaan liquid desiccant. Liquid desiccant dapat digunakan untuk menghilangkan kelembaban dari udara, yang dapat mengurangi beban pada sistem pendingin ruangan dan menghemat energi.  Namun, penggunaan liquid desiccant masih belum banyak digunakan di sektor HVAC.

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Indonesia is a country with relatively high humidity and hot weather, therefore, it requires air drying equipment to reduce humidity to a comfortable level for humans. Air drying systems are more environmentally friendly as an alternative technology for humidity reduction, especially in cases with high latent loads to maintain air quality. This technology is more efficient in hot and humid climates like Indonesia. This research conducted experimental investigations to determine the humidity ratio to air to understand the characteristics of ionic liquid using an air drying apparatus. In this experiment, the ionic liquid will pass through wooden blades that function as a heat exchanger, and the ionic liquid will circulate for approximately two hours. The experiment varied the flow rate of the ionic liquid from 200 to 600 L/h, and the resulting humidity ratio ranged from -0.10 to -0.56 g/kg. With an increase in the flow rate, the magnitude of the humidity ratio also increased. Energy consumption worldwide is increasing every year, especially in industries and the transportation sector. This high energy consumption results in harmful carbon dioxide emissions that negatively impact the environment and human health. One way to reduce energy consumption and carbon dioxide emissions is by using efficient HVAC (Heating, Ventilation, and Air Conditioning) systems. Currently, extensive research is being conducted to find more efficient HVAC system solutions. One promising solution being developed is the use of liquid desiccants. Liquid desiccants can remove moisture from the air, reducing the load on the room's cooling system and saving energy. However, the use of liquid desiccants is still not widely adopted in the HVAC sector."

"This book of general analytical chemistry, as opposed to instrumental analysis or separation methods, in aqueous solutions is focuses on fundamentals, which is an area too often overlooked in the literature. Explanations abound of the chemical and physical principles of different operations of chemical analysis in aqueous solutions. Once these principle are firmly established, numerous examples of applications are also given."

"Stigmasterol glukosida (STG) ditemukan di karantin, yang mengandung campuran STG dan beta-sitosterol glukosida (1: 1), dan terdapat pada buah pare (Momordica charantia L.) (BP). Tujuan penelitian ini adalah untuk mengoptimalkan ekstraksi STG dari BP dengan menggunakan metode ekstraksi berbantuan ultrasonikasi-cairan ionik (IL-UAE) diikuti dengan ekstraksi cair-cair. Optimasi bertujuan untuk mendapatkan kandungan STG tertinggi dan meliputi optimasi jenis pelarut, konsentrasi pelarut, waktu ekstraksi, dan rasio pelarut terhadap sampel, yang dianalisis dengan metodologi permukaan respons (RSM). Ekstrak yang diperoleh diukur dengan kromatografi cair kinerja tinggi (KCKT). Metode UAE dibandingkan dengan metode ekstraksi maserasi. Hasil penelitian menunjukkan bahwa kondisi ekstraksi optimum menggunakan pelarut 1-butil-3-methylimidazolium tetrafluoroborate (BMIMBF4) dengan konsentrasi 0,61 M, waktu ekstraksi 47,43 menit, dan perbandingan pelarut terhadap sampel 10: 1. Kondisi optimum menghasilkan kandungan STG aktual sebesar 1,90 mg/g, yang mendekati kandungan RSM prediksi optimal (1,95 mg/g) untuk ekstraksi cair. Setelah ekstraksi cair-cair, kandungan STG meningkat menjadi 4,96 mg/g. Metode ekstraksi UAE dan maserasi memperoleh jumlah STG masing-masing 1,05 mg/g dan 1,44 mg/g. Penelitian ini menunjukkan bahwa dibandingkan dengan metode ekstraksi maserasi, ekstraksi IL-UAE memberikan hasil STG yang lebih tinggi.

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Stigmasterol glucoside (STG) is found in charantin, which contains a mixture of STG and beta-sitosterol glucoside (1:1), and is present in bitter melon fruit (Momordica charantia L.) (BMF). The study aim was to optimise extraction of STG from BMF by using an ionic liquid–ultrasonication-assisted extraction (IL-UAE) method followed by liquid–liquid extraction. The goal of optimisation was to obtain the highest STG content and involved optimising the solvent type, solvent concentration, extraction time and solvent-to-sample ratio, which were analysed by response surface methodology (RSM). The obtained extract was measured by high-performance liquid chromatography. The UAE method was compared with a maceration extraction method. The results show that the optimum extraction conditions were using 1-butyl-3-methylimidazolium tetrafluoroborate (BMIMBF4) as a solvent with concentration of 0.61 M, an extraction time of 47.43 minutes and a solvent-to-sample ratio of 10:1. The optimum conditions produced an actual STG content of 1.90 mg/g, which was close to the optimum predicted RSM content (1.95 mg/g) for liquid extraction. After liquid–liquid extraction, the STG content increased to 4.96 mg/g. The UAE and maceration extraction methods obtained STG amounts of 1.05 mg/g and 1.44 mg/g, respectively. This study showed that compared with the maceration extraction method, IL-UAE extraction provided a higher STG yield."