Amine-functionalized MCM-48 as Adsorbent of Zn2+ and Ni2+ Ions

A compound, 3-aminopropyltrimetoxy silane, has been used to modify mesoporous silica, MCM-48. The modified silica (NH2-MCM-48) was utilized to remove Zn2+ and Ni2+ ions from solutions. The mesoporous material was synthesized in the alkaline solution. Characterization of the unmodified materials was conducted by X-ray diffraction and FT-IR spectroscopy. The ions adsorbed on NH2-MCM-48 were studied at various pHs, contact times and initial ions concentrations. An Atomic Absorption Spectrophotometer (AAS) measured the ions content in the solution.. Pseudo-first-order and pseudo-second-order models performed the kinetic adsorption. The adsorption isotherm was examined by Langmuir and Freundlich isotherms. The result found that optimum contact time for the adsorption of Zn2+ ion was lower than that for Ni2+ ion. The adsorption followed the pseudo-second-order model with the adsorption rate of 4.56x10-2 g mg-1 min-1 for Zn2+ ion and 7x10-4 g mg-1 min-1 for Ni2+ ion. The optimum pH was 6 and 4 for Zn2+ and Ni2+ adsorption, respectively. The uptake of both ions from solutions by NH2-MCM-48 fixed better the Langmuir than the Freundlich model with the adsorption capacity of 0.55 and 0.43 mmol g-1, correspondingly. This research work provides valuable information on the interaction between the ions and the functional group of adsorbent

The Star Clusters of the Small Magellanic Cloud: Structural Parameters

We present structural parameters for 204 stellar clusters in the Small Magellanic Cloud derived from fitting King and Elson, Fall, & Freeman model profiles to the V-band surface brightness profiles as measured from the Magellanic Clouds Photometric Survey images. Both King and EFF profiles are satisfactory fits to the majority of the profiles although King profiles are generally slightly superior to the softened power-law profiles of Elson, Fall, and Freeman and provide statistically acceptable fits to ~90% of the sample. We find no correlation between the preferred model and cluster age. The only systematic deviation in the surface brightness profiles that we identify is a lack of a central concentration in a subsample of clusters, which we designate as "ring" clusters. In agreement with previous studies, we find that the clusters in the SMC are significantly more elliptical than those in the Milky Way. However, given the mean age difference and the rapid destruction of these systems, the comparison between SMC and MW should not directly be interpreted as either a difference in the initial cluster properties or their subsequent evolution. We find that cluster ellipticity correlates with cluster mass more strongly than with cluster age. We identify several other correlations (central surface brightness vs. local background density, core radius vs. tidal force, size vs. distance) that can be used to constrain models of cluster evolution in the SMC.Comment: 14 pgs., accepted for publication in A

PEMBELAJARAN FISIKA UNTUK MENUMBUHKAN KEMAMPUAN BERPIKIR HIPOTETIKAL DEDUKTIFPADA SISWA SMA

Penelitian ini bertujuan untuk mendeskripsikan kemampuan berpikir siswa SMA di kota Semarang yang hasilnya dijadikan dasaruntuk pengembangan model pembelajaran fisika yang mampu menumbuhkan kemampuan berpikir Hipotetikal Deduktif padasiswa SMA di Kota Semarang. Metode penelitian yang digunakan dalam penelitian ini adalah Research and Development (R &amp; D),yang terdiri dari dua tahap. Penelitian tahap I bertujuan untuk mendeskripsikan kemampuan berpikir siswa SMA di kota Semarang.Penelitian tahap II bertujuan untuk mengembangkan model pembelajaran fisika yang mampu menumbuhkan kemampuan berpikirHipotetikal Deduktif di Kota Semarang dengan berdasar pada hasil penelitian tahap I dan mencari tahu keefektifan model tersebut.Hasil penelitian tahap I menunjukkan mayoritas (78,28%) siswa SMA di kota Semarang berada pada tingkat kemampuan berpikirEmpirikal Induktif, dan sisanya berada pada tingkat Transisi. Hasil penelitian tahap II adalah model pembelajaran denganpendekatan inkuiri latihan penelitian, yang memberikan kesempatan lebih luas kepada siswa untuk berhipotesis, mengidentifikasidan merencanakan percobaan, dan menarik kesimpulan dari hasil percobaan, mampu menumbuhkan kemampuan berpikirHipotetikal Deduktif pada siswa SMA di kota Semarang. Hasil uji hipotesis diperoleh thitung sebesar -11.95 dan ttabel= 2.64 yangmenunjukkan thitung tidak berada pada daerah penerimaan Ho. Dengan demikian dapat disimpulkan model pembelajaran inisecara signifikan mampu menumbuhkan kemampuan berpikir Deduktif pada siswa SMA di kota Semarang. This study aims to describe thinking ability of SHS student in Semarang. The result of the study will be used as a base of physicslearning model development which can grow hypothetical-deductive thinking ability of the student. The research metode used wasResearch and Development (R &amp; D), consisting of two stages. The result of first stage shows that 78.28% of SHS student inSemarang has the level of empirical-inductive thinking ability, while the remaining has ability of transition level. The second stage ofthe study resulted a model of physics learning with inquiry approach of doing research practice, giving more chance to student togive hyphotesis, identify and plan a research and derive a conclusion, and being able to grow hypothetical-deductive thinking to thestudent. It was concluded that the learning model developed can grow hypothetical-deductive thinking ability of SHS student inSemarang significantly.Keywords: hypothetical-deductive; thinking ability; Physics learning</p

PENGEMBANGAN PERANGKAT PERKULIAHAN KURIKULUM BERBASIS KOMPETENSI DAN KONSERVASI MELALUI LESSON STUDY UNTUK PENGUATAN LAYANAN PERKULIAHAN BAGI DOSEN MUDA DI FMIPA UNNES

Penelitian bertujuan untuk mengetahui; kefektifan perangkat perkuliahan berbasis kompetensi dan konservasi yang dikembangkan melalui kegiatan lesson study. Penelitian menerapkan metode deskriptif kualitatif dengan menerapkan langkah-langkah lesson study. Hasil penelitian perangkat perkuliahan yang dikembangkan melalui kegiatan lesson study efektif diterapkan. The study to determine; the effective of competency based learning and conservation to developed through lesson study. Apply to descriptive method qualitative research by applying the steps of lesson study. The results of the research tools developed through the course lesson study effective applied.</p

Hubungan Bobot Telur dengan Bobot Tetas dan Bobot Tetas dengan Bobot Badan Ayam Merawang G1 Sampai Umur 4 Bulan

. Penelitian ini bertujuan untuk mengetahui hubungan bobot telur dengan bobot tetas dan bobot tetas dengan bobot badan, pertambahan bobot badan dan penciri ukuran dan bentuk tubuh ayam Merawang jantan dan betina (G1) sampai umur 4 bulan. Metode penelitian adalah metode eksperimen. Materi penelitian yaitu telur ayam Merawang sebanyak 315 butir, menghasilkan 174 ekor ayam Merawang yang terdiri 68 ekor jantan dan 106 ekor betina. Data yang dihimpun meliputi: bobot telur, bobot tetas, bobot badan umur 1-4 bulan serta pertambahan bobot badan dan ukuran-ukuran tubuh. Perbedaan rataan bobot telur, bobot tetas, bobot badan serta pertambahan bobot badan dianalisis menggunakan Uji-t. Analisis Regresi dan Korelasi digunakan untuk melihat hubungan dan keeratan hubungan antara bobot telur dengan bobot tetas dan bobot tetas dengan bobot badan dari umur 1-4 bulan. Analisis komponen utama digunakan untuk mengidentifikasi penciri bentuk dan ukuran tubuh. Pengolahan data menggunakan perangkat lunak statistika Minitab versi 18. Hasil penelitian ini menunjukkan bahwa rataan bobot telur, bobot tetas, bobot badan, pertambahan bobot badan dan ukuran-ukuran tubuh ayam Merawang jantan berbeda nyata (P<0,05) lebih tinggi dibandingkan dengan ayam Merawang betina. Bobot telur berpengaruh nyata terhadap bobot tetas dan bobot tetas berpengaruh nyata terhadap bobot badan umur 1 hari - 4 bulan. Keeratan hubungan bobot telur dengan bobot tetas serta bobot tetas dengan bobot badan umur 1 hari - 4 bulan positif dan signifikan. Penciri ukuran tubuh pada ayam Merawang jantan dan betina yaitu lingkar dada, sedangkan penciri bentuk tubuh yaitu panjang tubuh atas dan panjang dada.The Relationship Between Egg Weight with Hatching Weight and Hatching Weight with Body Weight G1 of Merawang Chicken Aged up to 4 Month