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"Dalam proses produksinya, PT. Pupuk Kujang mendirikan Central Control Building sebagai pusat pengawasan proses produksi Kujang 1B. Dengan menggunakan sistem peralatan canggih dengan nama Distribution Control System (DCS) maka diperlukan kondisi ruang kerja yang khusus, yaitu harus berada dalam suhu ruangan 18°C. Keadaan itu mengakibatkan pekerja terpajan suhu dingin selama jam kerjanya. Suhu tersebut merupakan suhu yang berada di bawah nilai suhu nyaman. Hal ini mengakibatkan pekerja merasa terganggu oleh dingin tersebut yang pada akhirnya dapat berpengaruh negatif bagi kesehatan pekerja.Penelitian ini membahas tentang gambaran pajanan suhu dingin terhadap kejadian hipotermia pada pekerja operator DCS di ruang kontrol Gedung CCB Kujang 1B PT. Pupuk Kujang Cikampek tahun 2009. Penelitian ini merupakan penelitian deskriptif kuantitatif dengan disain cross-sectional.Hasil penelitian menunjukkan bahwa suhu control room Gedung CCB Kujang 1B berada di bawah nilai ambang batas (NAB) suhu nyaman (21?30°C) berdasarkan Surat Edaran Menteri Tenaga kerja dan Transmigrasi Nomor SE.01/MEN/1978. Namun, nilai Indeks Suhu Bola Basah (ISBB) control room tersebut masih berada dalam batas yang diperkenankan menurut Keputusan Menteri Tenaga Kerja No: Kep- 51/Men/1999.Penelitian ini juga tidak menemukan adanya kasus hipotermia pada pekerja operator DCS, karena penurunan suhu tubuh yang terjadi masih berada di batas suhu normal. Berdasarkan hasil tersebut, peneliti menyarankan agar dilakukan pengendalian engineering berupa pengaturan ulang suhu control room hingga mencapai suhu nyaman yang diperkenankan (21°C) atau pemasangan pembatas yang memisahkan antara pekerja dengan sumber pendingin (air conditioner - AC) serta memperbaiki fasilitas alat pelindung diri seperti jaket, sarung tangan dan penutup kepala. Memperbanyak aktivitas fisik saat bekerja serta lebih sering menyempatkan minum dan makan juga disarankan agar panas tubuh tidak hilang. ......In the process of production, PT. Pupuk Kujang establish Central Control Building as the central control of the production process Kujang 1B. By using the system with the sophisticated equipment Distribution Control System (DCS) is required then the condition that a special work space, must be in the room temperature 18°C. Circumstances that result in workers expose to cold temperatures during work hours. That temperature is below the temperature comfortable. This resulted in the workers feel disturbed by the cold, which in turn can negatively affect the health of workers.This study discusses illustration exposure to cold temperature incident hypothermia service workers on the DCS control room in Building CCB Kujang 1B PT. Pupuk Kujang Cikampek 2009. This research is descriptive quantitative research with cross-sectional design.Results of research indicate that the temperature control room building CCB Kujang 1B under the threshold limit value (TLV) temperature comfortable (21-30°C) based on the Circular Letter of the Minister of Manpower and Transmigration No. SE.01/MEN/1978. However, the value of Wet Bulb Globe Temperature (WBGT) control room is still in the limit permitted by the Minister of Manpower Decree No: Kep-51/Men/1999.This study also did not find any cases hypothermia on the DCS operator workers, because a decrease in body temperature that°Ccurred was in the normal temperature limits. Based on the results, the researchers suggested that the form of engineering control be reset control room temperature to reach a comfortable temperature allowed (21°C) or the barrier that separates between the workers, the source cooling (air conditioner) equipment and improve facilities such as selfprotective jacket, gloves and headgear. Increase physical activity at work and more often to eat and drink also suggested that body heat is not lost."

"Di dunia pertambangan batu bara dengan metode open pit banyak menggunakan unit excavator. Karya ilmiah ini membahas Preventive maintenance pada KOMATSU PC2000-8 di site PAMA FMC Bendili Sangatta Kalimantan Timur. Preventive maintenance yang dilakukan berfokus pada komponen Cylinder dimana komponen tersebut menjadi vital dikarenakan biaya perawatan dan penggantian yang cukup besar apabila terjadi kerusakan. Hal ini sejalan dengan implementasi K3LH yaitu mengurangi pencemaran lingkungan hidup akibat dari pencemaran pelumas hidrolik bekas pakai apabila terjadi kerusakan. Lebih jauh lagi akibat kerusakan pada komponen tersebut berpotensi merusak keseluruhan kualitas pelumas hidrolik dan harus dilakukan penggantian pelumas hidrolik. Tindakan Preventive maintenance pada cylinder yaitu monitoring kondisi suhu kerja Cylinder dengan adanya monitoring suhu kerja, kita dapat memastikan lebih awal sebelum terjadinya kerusakan pada komponen Cylinder. Secara teknis suhu kerja antara Cylinder kanan dan kiri pada KOMATSU PC2000-8 akan selalu sama. Apabila terjadi kerusakan maka suhu Cylinder akan mengalami perbedaan. Perbedaan suhu ini akibat dari gesekan yang tidak normal yang terjadi antara piston dan tube Cylinder......In the sector of coal mining with the open pit method many use excavator units. This scientific paper discusses preventive maintenance on KOMATSU PC2000-8 at the PAMA FMC Bendili Sangatta site, East Kalimantan. Preventive maintenance is carried out focusing on cylinder components where these components are vital due to the relatively large maintenance and replacement costs in the event of damage. This is in line with the implementation of K3LH and reducing environmental pollution as a result of contamination of used hydraulic lubricants. Furthermore, due to damage to these components it has the potential to damage the overall quality of the hydraulic lubricant and the hydraulic lubricant must be replaced. Preventive maintenance measures for cylinders and monitoring the working temperature conditions of cylinder components by monitoring working temperatures, we can ensure earlier before damage occurs to Cylinder components. Technically the working temperature between the right and left cylinders on KOMATSU PC2000-8 wil be same. If there is damage, the temperature of the right and left cylinders will be difference. Difference of temperature results from abnormal friction that occurs between the piston and cylinder tube."

"Polymer blends offer properties not easily obtained through the use of a single polymer, including the ability to withstand high temperatures. High temperature polymer blends outlines the characteristics, developments, and use of high temperature polymer blends.The first chapter introduces high temperature polymer blends, their general principles, and thermodynamics. Further chapters go on to deal with the characterization of high temperature polymer blends for specific uses, such as fuel cells and aerospace applications. The book discusses different types of high temperature polymer blends, including liquid crystal polymers, polysulfones, and polybenzimidazole polymer blends and their commercial applications.High temperature polymer blends provides a key reference for material scientists, polymer scientists, chemists, and plastic engineers, as well as academics in these fields."

"George Lai?s 1990 book, High-Temperature Corrosion of Engineering Alloys, is recognized as authoritative and is frequently consulted and often cited by those in the industry. His new book, almost double in size with seven more chapters, addresses the new concerns, new technologies, and new materials available for those engaged in high-temperature applications. As we strive for energy efficiency, the realm of high-temperature environments is expanding and the need for information on high temperature materials applications was never greater.In addition to extensive expansion on most of the content of the original book, new topics include erosion and erosion-corrosion, low NOx combustion in coal-fired boilers, fluidized bed combustion, and the special demands of waste-to-energy boilers, waste incinerators, and black liquor recovery boilers in the pulp and paper industry. The corrosion induced by liquid metals is discussed and protection options are presented. Hydrogen damage is characterized and solutions given."

"The high temperatures generated in gases by shock waves give rise to physical and chemical phenomena such as molecular vibrational excitation, dissociation, ionization, chemical reactions and inherently related radiation. In continuum regime, these processes start from the wave front, so that generally the gaseous media behind shock waves may be in a thermodynamic and chemical non-equilibrium state. This book presents the state of knowledge of these phenomena. Thus, the thermodynamic properties of high temperature gases, including the plasma state are described, as well as the kinetics of the various chemical phenomena cited above. Numerous results of measurement and computation of vibrational relaxation times, dissociation and reaction rate constants are given, and various ionization and radiative mechanisms and processes are presented. The coupling between these different phenomena is taken into account as well as their interaction with the flow-field. Particular points such as the case of rarefied flows and the inside of the shock wave itself are also examined. Examples of specific non-equilibrium flows are given, generally corresponding to those encountered during spatial missions or in shock tube experiments."

"Biomaterial komposit hidroksiapatit/kitosan adalah material yang penting untuk aplikasi medis, misalnya pada pembuatan scaffold tulang. Kitosan difosforilasi menggunakan asam ortofosfat sebelum pembuatan biomaterial. Biomaterial dengan komposisi berat 70% hidroksiapatit dan 30% kitosan dibuat menggunakan metode thermally induced phase separation (TIPS) pada temperatur pembekuan -20, -30, -40 dan -80°C sebelum freeze drying selama tiga hari. Penelitian memperlihatkan bahwa pada temperatur pembekuan -20°C, diperoleh ukuran pori terbesar, 48.24 μm, modulus kompresi tertinggi, 376.9 KPa, dan kekuatan tekan tertinggi, 38.4 KPa. Penelitian mengindikasikan bahwa pembuatan scaffold menggunakan metode TIPS pada temperatur pembekuan lebih tinggi menghasilkan sifat-sifat scaffold yang lebih baik untuk aplikasi medis.

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Biomaterials composite of hydroxyapatite/chitosan is preeminent material for medical application, such as bone scaffold fabrication. The chitosan had been phosphorylated using orthophosphoric acid prior to the biomaterials fabrication. Biomaterials with the weight composition of 70% hydroxyapatite and 30% chitosan has been fabricated using the thermally induced phase separation (TIPS) method in the freezing temperatures of -20, -30, -40 and -80°C before three days freeze drying. This research showed that in the freezing temperatures of -20°C, highest compression modulus of 376.9 KPa, highest compressive strength of 38.4 KPa and biggest pore size of 48.24 μm are achieved. This research indicates that scaffold fabrication using TIPS method in higher freezing temperature results in better scaffold properties for medical application."

"ABSTRAK

Indonesia saat ini termasuk salah satu negara peng-ekspor terbesar gas alam cair atau liquid natural gas (LNG) di dunia. Gas alam cair biasanya ditransfer dalam keadaan cair pada temperatur minimum cryogenic , yaitu sekitar -1650C. Tidak banyak material yang bisa tahan untuk digunakan pada temperatur dingin ekstrem tersebut. Material baja SS 304L, SS 316L dan Aluminium AL5052 adalah beberapa material yang biasa digunakan pada temperatur Cryogenic.

Pengujian dilakukan dengan uji impak charpy pada beberapa temperatur dingin yaitu 00C, -500C, dan -1960C, dengan media pendingin es kering (dry ice) dan Nitrogen cair. Pengujian kekerasan dan struktur mikro juga dilakukan untuk melihat apakah ada perbedaan akibat temperatur dingin.

Dari hasil penelitian menunjukkan material SS 304L dan SS316L memiliki sifat ketangguhan untuk digunakan pada marine loading arm pada temperatur dingin cryogenic.

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ABSTRAK

Indonesia is one of the largest liquefied natural gas or liquid natural gas (LNG) exporter countries in the world. Liquefied natural gas is usually transferred in a liquid state at minimum cryogenic temperature, which is about -1650C. Not a lot of material can with stand the extremely cold temperature to be later utilized. Material steel SS 304L, SS 316L and Aluminum AL5052 are some commonly used materials at cryogenic temperatures.

An observation is conducted through charpy impact test on some cold, to freezing temperatures such as 00C, -500C, and -1960C, with dry ice and liquid nitrogen as the cooling medium. The microstructure and solidity test are also applied to see whether there is a difference taking place in a cold temperature. The observation yields the result that SS304L and SS316L possess an endurance quality to be used for marine loading arm in cryogenically cold temperature.

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"Helium Cryogenics, 2nd edition brings these advances in helium cryogenics together in an updated form. As in the original edition, the author's approach is to survey the field of cryogenics with emphasis on helium fluids. This approach is more specialized and fundamental than that contained in other cryogenics books, which treat the associated range of cryogenic fluids. As a result, the level of treatment is more advanced and assumes a certain knowledge of fundamental engineering and physics principles, including some quantum mechanics. The goal throughout the work is to bridge the gap between the physics and engineering aspects of helium fluids to provide a source for engineers and scientists to enhance their usefulness in low-temperature systems."

"This thesis presents an experimental and theoretical study of the coherent properties of trapped atomic ensembles at high densities, which are essential to many of the aforementioned applications. The study focuses on how inter-particle interactions modify the ensemble coherence dynamics, and whether it is possible to extend the coherence time by means of external control. The thesis presents a theoretical model which explains the effect of elastic collision of the coherence dynamics and then reports on experiments which test this model successfully in the lab. Furthermore, the work includes the first implementation of dynamical decoupling with ultra-cold atomic ensembles. It is demonstrated experimentally that by using dynamical decoupling the coherence time can be extended 20-fold. This has a great potential to increase the usefulness of these ensembles for quantum computation."