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Abstrak :
e purpose of this paper was to investigate the performance of ceramic filters made from a mixture of natural clay, rice bran, and iron powder in removing cadmium from pulp industry effluent. Some parameters were examined such as acidity, total dissolved solid (TDS), total suspended solid (TSS), electrical conductivity (EC), and cadmium concentration. Results showed that the composition percentage of the ceramic filter, which in this case amounted to 87.5% natural clay, 10% rice bran, and 2.5% iron powder, may decrease cadmium concentration in pulp industry effluent by up to 99.0%. Furthermore, the permeate flux decreased after 30 minutes of filtration time, and subsequently became constant at one hour of contact time. In addition, Scanning Electron Microscope (SEM) micrographs of the ceramic filter surfaces indicate that ceramic filters have a random pore structure and can be categorized as microfiltration filters.

Abstrak :
Pendahuluan: Perubahan sistem pertahanan pejamu atau kondisi rongga mulut dapat menyebabkan infeksi Candida albicans (C. albicans) yang disebut kandidiasis oral. Xanthorrhizol adalah komponen aktif Temulawak (Curcuma xanthorrhiza Roxb.) yang memiliki efek antijamur. Gambar Scanning Electron Microscope (SEM) sel C. albicans yang terpapar xanthorrhizol menunjukkan penonjolan sitoplasma dan adhesi antar sel. Tidak diketahui bagaimana perubahan ultrastruktural pada sel C. albicans. Tujuan: Menggunakan TEM untuk menganalisis perubahan ultrastruktur sel C. albicans pada biofilm fase pematangan pasca-inhibisi dengan Ekstrak Etanol Temulawak (EET). Metode: Biofilm C. albicans ATCC 10231 yang ditumbuhkan pada kawat selama 1,5 jam dihambat dengan 25% EET selama 48 jam. Kelompok kontrol positif tidak diberi nistatin sedangkan kelompok kontrol negatif tidak diberi apa-apa. Sampel difiksasi dengan 2,5% glutaraldehid, didehidrasi dengan etanol, dan dibenamkan dalam resin spurr sebelum diamati dengan TEM. Hasil: Terlihat distorsi dinding sel, membran plasma, dan organel serta invaginasi membran plasma. Kesimpulan: Penghambatan biofilm C. albicans ATCC 10231 oleh 25% EET menyebabkan kerusakan pada ultrastruktur sel C. albicans ATCC 10231.

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Changes of hosts defense system or oral condition causing infection of Candida albicans (C. albicans) is called oral candidiasis. Xanthorrhizol is an active component of javanese turmeric (Curcuma xanthorrhiza Roxb.) which has antifungal effect. C. albicans cells Scanning Electron Microscope (SEM) image exposed to xanthorrhizol showed cytoplasm protrusion and clumping. The ultrastructure changes inside the C. albicans cell is not known yet. Objective: Using TEM to analyse the ultrastructure image of C. albicans ATCC 10231 cells in maturation phase of biofilm inhibited by 25% EET. Methods: C. albicans ATCC 10231 biofilm which had been cultured on wire for 1.5 hours was inhibited by 25% EET. Group of positive control was exposed by nystatin whereas group of negative control was exposed to nothing. Sampel was being fixated with glutaraldehyde 2.5%, dehydrathed by ethanol, and embedded inside spurrs resin before being observed with TEM. Results: Cell wall, plasma membrane, and organelles distortion, along with plasma membrane invagination. Conclusion: C. albicans ATCC 10231 biofilm inhibition with 25% EET caused damages in C. albicans ATCC 10231 cells ultrastructure.

Abstrak :
The SBA-l5 material can be applied on many industries such as catalyst, adsorbent and membrane material. Pore size in SBA-I5 can be categorized in mesoporous material, because the size ranges from 2- 50 nm. Pore diameter generally can be observed by Scanning Electron Microscope (SEM) or Transmission Electron Microscope (TEM). Another method to determine the pore diameter is using a Atomic Force Microscope (AFA/D. The topography observation from AFM can identify the size and pore shape of SBA-I 5 in nanometer order: The result of AFM showed that the pore size ofSBA-i5 is 3.27 nm.

Abstrak :
Paduan Al-Zn-Mg (Seri 7xxx) umumnya diperkuat melalui perlakuan penuaan, dengan pembentukan presipitat. Selain itu, paduan dapat diperkuat pula dengan penambahan 0.4 % berat Ti yang akan memperhalus butir. Tujuan dari penelitian ini adalah untuk mengetahui pengaruh Ti dalam penguatan presipitasi paduan Al-4.4Zn-1.6Mg-0.4Ti (% berat) pada berbagai temperatur. Paduan ini diproses melalui pengecoran dengan proses squeeze casting, homogenisasi pada temperatur 400 oC selama 4 jam, laku pelarutan dengan variasi temperatur 220, 420, dan 490 oC selama 1 jam, pencelupan air, lalu dilakukan penuaan pada temperatur 130 °C selama 48 jam. Karakterisasi yang dilakukan berupa pengamatan struktur mikro menggunakan mikroskop optik, dan Scanning Electron Microscope (SEM) – Energy Dispersive Spectroscopy (EDS), pengujian kekerasan Rockwell, X-Ray Diffraction (XRD), dan Differential Scanning Calorimetry (DSC). Penambahan 0.4 % berat Ti selain memperhalus dan membulatkan butir, menurunkan tegangan permukaan antarmuka matriks dan fasa kedua, dan pelarutan fasa kedua menjadi lebih mudah. Banyaknya fasa kedua yang larut berpengaruh dengan kekerasan setelah laku pelarutan dan penuaan. Kekerasan akhir setelah penuaan dengan laku pelarutan 220, 420, dan 490 oC sebesar 38.26, 63.76, dan 63.36 HRB. Nilai kekerasan tersebut lebih tinggi daripada paduan tanpa Ti karena pelarutan fasa kedua yang lebih banyak menyebabkan pembentukan presispitat yang lebih banyak pula......Al-Zn-Mg alloys (7xxx series Al alloys) are commmonly hardened with ageing treatment, to form precipitates. To further increase the strength, Ti is added to decrease the grain size. The objective of this study is to investigate the role of Ti in the precipitation strengthening of Al-4.4Zn-1.6Mg-0.4Ti (wt.%) alloy. The alloy was fabricated by squeeze casting process. Then, the alloy was homogenized at 400 oC for 4 hours, solution treated at 220, 420, and 490 oC for 1 h followed by water quenching, then aged at 130 oC for 48 h. Characterization was performed by optical microscope, Scanning Electron Microscope (SEM) – Energy Dispersive Spectroscopy (EDS), Rockwell hardness testing, X-Ray Diffraction (XRD), and Differential Scanning Calorimetry (DSC). The addition of 0.4 wt. % Ti resulted finer and rounder grains which possess lower surface tension between the α-Al matrix and second phase interface to dissolves second phases easier during solution treatment. The amount of dissolved second phases will affect the final hardness after ageing to 38.26, 63.76, and 63.36 HRB with solution treatment temperature of 220, 420, and 490 °C, respectively. Besides, the hardness value of 0.4 wt. % Ti added alloy was higher than that of the alloy without Ti addition. It was due to higher second phase dissolution which leads to more precipitates formed.