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Abstrak :
Pembentukan komposit matrik aluminium paduan AC8A/SiCp dengan metode hot-press di lingkungan atmosfer yang tidak dikondisikan berpengaruh terhadap karakteristik material yang dihasilkan. Dilakukan analisa terhadap karakteristik matrik terbentuk dan ikatan antar muka matrik dan penguat, untuk melihat pengaruh elemen paduan, lingkungan atmosfer dan parameter proses hot-press terhadap material. Observasi awal parameter proses pembentukan komposit menggunakan serbuk alumunium murni Merck, menunjukkan terbentuknya struktur komposit Al/SiCp yang padat. Perbandingan komposit AC8A/SiCp yang dibuat dengan metode hot-press di lingkungan atmosfer dan metode metalurgi serbuk konvensional dalam ruang vakum, menunjukkan komposit dibuat dengan metode hot-press dengan tekanan 425 MPa, 380oC selama 5 menit, memiliki fasa Al, Si, SiC dengan densitas relatif 99%, dan komposit dibuat dengan metode metalurgi serbuk konvensional pada 600oC selama 6 jam memiliki fasa Al, Si, SiC, Al2O3 dengan densitas relatif 84%. Analisa ikatan antar muka matrik dan penguat melalui pengamatan fraktografi terhadap tiga jenis komposit yang dibentuk dari SiC tanpa pelapis, SiC berlapis MgAl2O4 dan SiC berlapis SnO2, menunjukkan terjadinya ikatan antar muka yang baik pada ketiganya, dimana sifat mekanis tertinggi dimiliki komposit dengan SiC tanpa pelapis. Sifat mekanis komposit AC8A/SiCp naik bersamaan meningkatnya fraksi volume penguat, dimana komposit dengan 40% Vf SiCp memiliki kuat tekan 445 MPa, kekerasan 222 HVN. ......Producing aluminum alloy matrix composites AC8A/SiCp by powder metallurgy of hot-press method under unconditioned atmosphere environments may influence the characteristics of final material. Analysis of characteristics of formed matrix and interfacial bonding between matrix and reinforcement have been done to know about effects of Aluminium alloy elements, atmosphere environment and hot-press parameters. Preliminary observations of process parameters in producing composites using Merck?s pure aluminum powder, showed dense structure of formed composites Al/SiCp. Comparative analysis between AC8A/SiCp composites using the hot-press method in unconditioned atmosphere and conventional powder metallurgy with vacuum chamber, showed that hot-pressed using 425 MPa, 380oC in 5 minutes has phase of Al, Si and SiC, with relative density 99%; and using conventional powder metallurgy method with vacuum chamber in 600oC, 6 hours has phase of Al, Si, SiC, with relative density 84%. Interfacial bonding analysis by fractography of three composites : uncoated SiCp, SiCp coated with MgAl2O4 and with SnO2, showed that all types has good bonding strength, where uncoated SiCp has highest hardness and compressive strength. Composites hardness and compressive strength are increased along with increasing of reinforcement volume fraction, where 40% Vf SiCp has compressive strength of 445 MPa, hardness of 222 HVN.

Abstrak :
The book provides an up-to-date, in-depth survey across the entire field of atmospheric science, including atmospheric dynamics, radiation, cloud physics, chemistry, climate, numerical simulation, remote sensing, instruments and measurements, as well as atmospheric acoustics. The authors have provided a readily comprehensible and self-contained presentation of the complex field of atmospheric science. The topics are of direct relevance for aerospace science and technology. Future research challenges are identified.

Abstrak :
This book focuses on four themes : (1) evolving earth’s crust, (2) changing Baltic Sea, (3) climate change, and (4) planet earth, third stone from sun. The focus on these four topics provides both a state of the art review of earth science topics of particular importance to Scandinavia and the Baltic and also the global context in which a consideration of these topics must be made. It finishes by discussing our use of space born technologies for understanding these topics and places the earth within the context of our neighbouring planets and their satellites.

Abstrak :
Weird weather : tales of astronomical and atmospheric anomalies is about strange, unusual, and apparently inexplicable observations of the air and sky. Primarily these are in the earth's atmosphere, but there are corresponding phenomena in the atmospheres of other planets of the solar aystem, lightning on venus, jupiter, and saturn, whirlwinds and dust storms of mars, and auroras on jupiter. Topics include anomalous lights, anomalous sounds, spectacular effects of cloud illumination by the Sun or Moon, lightning phenomena, electrophonic sounds of lightning, aurora and meteors, tornado and whirlwind phenomena on Earth and Mars, usual atmospheric effects, mirages, and the possible astronomical influences on cloud and climate.