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"This book focuses on the biomedical aspects, while not ignoring other life-changing influences of space living. For example, what happens to people physiologically in the microgravity of space, where weight and the direction "up" become meaningless? Adapting to microgravity represents the greatest environmental challenge that life will have encountered since our ancestors moved from the seas to solid Earth. Away from Earth the human body will begin almost immediately to adapt and change, to be able to function in these strange environments. As a person adapts in space he or she will become less fit to live on earth."

"Penelitian ini bertujuan untuk mendapatkan kopolimer cangkok DPNR-g-PAN/PS yang tahan terhadap DME dengan melakukan uji perendaman terhadap DME berdasarkan pengaruh rasio monomer akrilonitril dan stirena. Hasil penelitian menunjukkan bahwa monomer akrilonitril AN dapat dicangkokkan pada karet alam dengan stirena ST sebagai ko-monomer. Dari karakteristik analisis spektrum dengan FTIR didapatkan gugus C N dan gugus benzena yang merupakan gugus dari poliakrilonitril PAN dan polistirena PS . Karakterisasi temperatur transisi gelas Tg dengan DSC menunjukkan bahwa nilai Tg kopolimer DPNR-g-PAN/PS lebih tinggi dari Tg DPNR. Dari karakteristik Efisiensi Cangkok EC didapatkan nilai tertinggi adalah 73,21 . Berdasarkan karakteristik cure didapatkan bahwa semakin kecil rasio AN/ST, nilai optimum cure semakin tinggi dan scorch time yang semakin rendah. Hasil dari sifat-sifat fisik tensile strength, elongation at break dan hardness menunjukkan keberhasilan kopolimerisasi. Pengujian DPNR dan DPNR-g-PAN/PS dilakukan dalam DME. Semakin besar komposisi monomer M dan AN, semakin kecil persentase swelling massa dan volume. Komposisi AN untuk swelling terendah adalah 92 . Komposisi ST optimal untuk memperkecil shrinkage adalah 20 . Swelling massa dan volume terrendah dicapai pada 23,14 dan 31,90 . Shrinkage massa dan volume terrendah dicapai pada masing-masing -3,64 dan -3,86 . Pada analisis spektrum FTIR karet vulkanisat, kemungkinan putusnya ikatan rangkap C=C hanya karena interaksi DME pada DPNR bebas. Hal ini yang menimbulkan terjadinya shrinkage. Kehadiran PAN sebagai polimer bebas dapat berfungsi sebagai penahan difusi, sehingga total PAN yang tergrafting dan PAN bebas dapat memperkecil swelling dan shrinkage. Pada perubahan sifat fisik, interaksi karet DPNR ataupun DPNR-g-PAN/PS dengan DME menyebabkan menurunnya nilai tensile strength, elongation at break dan hardness. Pada analisis SEM terlihat perbedaan yang terjadi akibat swelling dan shrinkage massa dan volume setelah perendaman. Pada pengujian perbandingan dengan Nitrile Butadiene Rubber NBR hasil menunjukkan bahwa daya tahan terhadap DME adalah NBR-1 < DPNR-g-PAN/PS < NBR-2. Dari hasil pengujian-pengujian dapat disimpulkan bahwa proses kopolimerisasi cangkok dapat meningkatkan daya tahan karet alam terhadap DME.

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This study aims to obtain graft copolymer DPNR g PAN PS which is resistant to immersion DME. The immersion test of the DME based on the ratio acrylonitrile and styrene monomer. The results showed that the monomer acrylonitrile AN can be grafted on natural rubber with styrene ST as co monomer. From the characteristics of the FTIR spectrum analysis obtained C N groups and clusters of benzene which is a group of polyacrylonitrile PAN and polystyrene PS . Characterization of the glass transition temperature Tg by DSC shows that Tg values copolymer DPNR g PAN PS higher than Tg DPNR. The characteristics of the Grafting Efficiency GE obtained the highest value is 73.21 . Based on the cure characteristics, it was found that the smaller the ratio AN ST, the higher of the optimum cure and the lower scorch time. The results of the physical properties of tensile strength, elongation at break and hardness show success copolymerization. The immersion test DPNR and DPNR g PAN PS performed in DME. The larger the monomer composition M and AN, the smaller the percentage of swelling mass and volume. The composition of AN to the lowest swelling is 92 . ST optimal composition to minimize the shrinkage is 20 . The lowest of the swelling mass and volume reached at 23.14 and 31.90 respectively. Mass and volume shrinkage achieved at the lowest 3.64 and 3.86 respectively. In the FTIR spectrum analysis of vulcanized rubber, the possibility of the outbreak of the C C double bond simply because of the interaction of the DPNR free and DME. This has led to an shrinkage. The presence of PAN as a free polymer can serve as a diffusion barrier, so that the total PAN grafted and PAN free can reduce swelling and shrinkage. On the change of physical properties, interaction DPNR rubber or DPNR g PAN PS with DME caused a decline in the value of tensile strength, elongation at break and hardness. In the SEM analysis of visible differences that occur due to swelling and shrinkage of mass and volume after immersion. In comparative testing with a Nitrile Butadiene Rubber NBR results indicate that resistance to DME is NBR 1 DPNR g PAN PS NBR 2. From the results of the tests can be concluded that the graft copolymerization process can improve the resistance of natural rubber to the DME."

"Analisis senyawa organik di laboratorium umumnya menggunakan pelarut organik untuk keperluan ekstraksi dan destilasi. Pelarut organik yang banyak digunakan adalah diklormetan dan n-heksan. Penggunaan diklormetan dan nheksan berisiko terhadap kesehatan pekerja laboratorium. Diklormetan adalah senyawa karsinogenik kategori 2 B menurut IARC, sedangkan pajanan heksan berisiko terhadap kerusakan sistem syaraf.Penelitian ini untuk mengetahui sebaran konsentrasi diklormetan dan n-heksan di ruangan laboratorium, profil pajanan dan pengendalian yang sudah dilakukan dan risiko pajanan berdasarkan konsentrasi diklormetan dan n-heksan pada pengambilan sampel perseorangan, durasi pajanan dan hazard rating.Hasil analisis konsentrasi diklormetan dan nheksan di seluruh ruangan laboratorium masih di bawah nilai rekomendasi treshold limit value dari American Conference of Governmental Industrial Hygienist. Sistem pengendalian pajanan secara administratif dan penggunaan alat pelindung diri sebagai pencegahan pajanan diklormetan dan n-heksan di laboratorium sudah memadai, namun diperlukan perbaikan untuk kondisi ventilasi di laboratorium sebagai bagian dari pengendalian teknis.Hasil analisis risiko kesehatan menggunakan sistem risk rating adalah teknisi laboratorium 1, operator GC ECD dan asisten laboratorium memiliki risiko kesehatan medium sedangkan operator GC MS dan Teknisi laboratorium 2 memiliki risiko kesehatan rendah terhadap pajanan n-heksan. Teknisi laboratorium 1, teknisi laboratorium 2 ,operator GC MS dan asisten laboratorium memiliki risiko kesehatan medium sedangkan operator GC ECD memiliki risiko kesehatan rendah terhadap pajanan diklormetan.

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Generally organic coumpound analysis in laboratory need organic solvent for extraction and distilation purpose. Dichlormethane and n-hexane are a common organic solvent for laboratory analysis. The use of dichlormethane and n-hexane in laboratory have a high risk for employees health. Diclormethane is classify as 2 B group of carcinogenic material of IARC, while n-hexane could chronically cause a nervous system damage.The purposes of this research are to determine the concentration of dichlormethane and n-hexane in workplace, the exposure and exist control profile in laboratory and to do chemical exposure risk assessment according to dichlormethane and n-hexane analysis from employees personal sampling, duration of exposure and hazard rating.The result of dichlormethane and n-hexane analysis in workplace are still below the value of treshold limit value of american conference of governmental industrial hygienist. Laboratory has a good administratif control and PPE control to prevent the exposure of dichlormethane and n-hexane but the enginering control need improvement for ventilation system.The result of n-heksan exposure health risk assessment using risk rating system are laboratory technician 1, GC ECD operator, and laboratory assistance were categorized as medium risk, while GC MS operator and laboratory technician 2 were categorized as low risk. The result of diklormetan health risk assesment were laboratory technician 1, laboratory technician 2, GC MS operator and laboratory assistance are categorized as medium risk, while GC ECD operator was categorized low risk."