Journal of Mathematical and Fundamental Sciences
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Efek Stimulatif dari Bacteria terhadap Pembentukan Tubuh-Buah Djamur Padi (Volvariella volvacea (Fr.) Sing.)
No full textRingkasan. Penelitian terhadap ada tidaknya efek stimulatif dari bakteria tertentu terhadap pembentukan tubuh-buah djamur padi (Volvariella volvacea (Fr.) Sing.) telah dilakukan dalam kondisi semi steril. Ternjata bahwa adanja bakteria tertentu merangsang pembentukan tubuh-buah djamur padi. Abstract. A study has been made on the stimulative effect of certain specific bacteria upon fruit body formation of rice straw mushroom (Volvariella volvacea (Fr.) Sing.) under semi-sterile condition. It was shown that the presence of specific bacteria stimulated fruit body formation of rice straw mushroom.
The Colour Magnitude Diagram of The Galactic Cluster NGC 6383
No full textAbstract. Almost all the stars in a circular area with a radius of about 12 min. of arc, were measured photometrically down to V="13".80 mag., using plates obtained with the Uppsala Schmidt telescope Mt. Stromlo and the Schmidt telescope at Lembang. The photographic measurement generally confirm Enggen's remarkable result that NGC 6383 is a very young cluster, similar to NGC 2264. Groups stars lying on different parts of the colour magnitude diagram NGC 6383, are discussed in connection with Herbig's idea about non-coevalness of stars in stellar cluster. Ichtisar. Hampir semua bintang dalam sebuah daerah bundar dengan djari2 kira2 12 menit busur, telah diukur setjara photometris sampai V = 13.80 magn., dengan menggunakan katja2 potret jang didapatkan dengan teropong Schmidt Uppsala di Observatorium Mt. Stromlo dan teropong Schmidt di Lembang. Kumpulan2 bintang jang terletak pada tempat2 jang berbeda-beda pada diagram warna magnitudo daripada NGC 6383 telah dibahas sehubungan dengan idee Herbig mengenai tidak dilahirkannja bintang2 dalam sebuah gugus bintang pada saat bersamaan
Soybean-Extract and Cane Molasses for Active Dried Yeast Production
No full textAbstract. Extract of germinating soybeans was used as enrichment in a medium of blackstrap cane molasses for producing active dried yeast. Optimum amount of soybeans and optimum germination time has been investigated. Yeast cells produced from a medium prepared from molasses, (NH4)2 SO4 and KH2PO4.Ichtisar. Ekstrak dari kedele berkatjambah telah dipakai untuk memperkaja perbenihan jang dibuat dari tetes untuk pembuatan ragi roti kering. Djumlah kedele dan waktu perketjambahan jang terbaik telah ditentukan. Ragi jang dibuat dari perbenikan tersebut mempunjai daja tahan lebih besar terhadap pengeringan daripada ragi jang dibuat dari perbenihan jang mengandung tetes, (NH4)2SG4 dan KH2PO4
Beberapa Kriteria Pembebanan Optimum Ekonomi Alat-alat Pembangkitan Termis
No full textIchtisar. Metoda pembebanan dan perentjanaan daripada alat2 pembangkitan tenaga listrik jang bekerdja setjara parallel dan untuk optimum ekonomi telah diperkembangkan setjara memuaskan. Dalam artikel ini dibahas keriteria2 sederhana untuk merentjanakan setjara optimum ekonomi sistim-sistim jang ketjil, padamana beberapa generator bekerdja setjara parallel, dan kehilangan2 transmisi dapat diabaikan.Abstract. The method of loading and scheduling of parallel operating power plants for optimum economy has been fairly well developed. For small system where several generators are operating in parallel and transmission losses can be neglected, simple criterions for economic scheduling and its limitation are discussed in this paper
Faint Hα-Emission Objects in Nebulosities Surrounding the Star m Cen.
Get PDFTudjuh puluh delapan buah bintang Hα-emisi jang baru dan dua buah kabut-planit telah diketemukan pada suatu survey dalam daerah kabut gelap dan bertjahaja pada lingkungan bintang m Cen. Pusat daerah ini terletak pada α=13h04m; δ=-63°30'(1875). Posisi kira-kira magnitudo V dan warna V-R telah ditentukan. Peta-peta jang menundjukkan letak benda-benda itu dilampirkan.Di antara bintang-bintang emisi ternjata ada 12 buah jang mungkin merupakan bintang berubah. Hal ini menjokong kesimpulan bahwa sebagian daripada bintang emisi jang lemah tjahajanya mungkin membentuk asosiasi-asosiasi T jang mempunjai hubungan dengan kabut-kabut tersebut di atas dan mungkin djuga mempunyai hubungan dengan asosiasi OB jang dinamakan I-Cru
The System of Gelled Foam of Clay-in-water Suspension for the Preparation of Lightweight Insulating Refractory: Part I. Formation and Gelling of Clay-Based Foam
Get PDFUnder neutral conditions colloidal plates of clay in water are negatively charged. When the pH of the clay-in-water dispersion is lowered slightly, positive charges can develop on the edges of the clay plates giving rise to an edge-to-face type gelation. Sodium fluosilicate, which has a rather high acidity and which is very slightly soluble in water, can be used as gelling agent. By beating a clay slip containing, a surfaceactive agent "Teepool" and sodium fluosilicate, one can obtain a stable foam followed by formation of a firm gel. When then the wet gel is dried a solid foam product is built up
A Combined Family of Ratio Estimators for Population Mean using an Auxiliary Variable in Simple Random Sampling
Get PDFThis paper proposes two new classes of ratio estimators for population mean when information on a known auxiliary variable is available in simple random sampling. A combined family of ratio estimators for estimating population mean by combining the two new estimators together in order to minimize the mean square error (MSE) is then suggested. The expressions for the bias and mean square error of all proposed estimators up to the first order of approximation were obtained. The performance of the proposed estimators was compared with that of existing estimators using both a theoretical and a simulation study. The proposed family of estimators was found to be more efficient than the existing estimators
Donskerâs Delta Functional of Stochastic Processes with Memory
Get PDFA class of stochastic processes with memory within the framework of the Hida calculus was studied. It was proved that the Donsker delta functionals of the processes are Hida distributions. Furthermore, the probability density function of the processes and the chaos decomposition of the Donsker delta functional were derived. As an application, the existence of the renormalized local times in an arbitrary dimension of the Riemann-Liouville fractional Brownian motion as a white noise generalized function was proved
On Kink-Dynamics of Stacked-Josephson Junctions
Get PDFDynamics of a fluxon in a stack of coupled long Josephson junctions is studied numericallv. Based on the numerical simulations, we show that the dependence of the propagation velocity c on the external bias current γ is determined by the ratio of the critical currents of thc two junctions J
A Study of Quantum dots of GaSb
Get PDFAbstract. Quantum Dots is a nano structured materials, which is an interesting object for fundamental study as well as for applications. Quantum Dots has been used for optoelectronic devices, such as fast detectors and for lasers. In this paper we report preliminary results of the preparation of quantum dots of GaSb in our laboratory. These dots are prepared by self-organized growth by MOCVD, using Trymethylgalium and Tridismethylaminoantimonat as metal organic sources and using GaAs as substrate. The results are studied by Scanning Electron Microscope. We propose further characterization of these quantum dots. Studi Mengenai Titik Kuantum GaSbSari. Quantum Dot adalah material yang mempunyai struktur nano, yang merupakan objek untuk penelitian fundamental maupun untuk penerapannya. Dalam makalah ini dilaporakan hasil-hasil yang pertama yang kita peroleh dalam pembuatan Quantum Dot dari GaSb dalam laboratorium kami. Quantum Dot ini telah ditumbuhkan dengan menggunakan penumbuhan yang "selforganized" dengan reactor MOCVD dengan mempergunakan Trimetilgalium dan Trisdismetilantimonat sebagai sumber-sumber metalorganic dan GaAs digunakan sebagai substrat. Hasilnya ditelaah dengan menggunakan SEM. Telat disarankan karakterisasi lanjutan yang harus dilakukan.