Pairing and Quadrupole Interactions in the Pseudo-Su(3) Shell Model.

Pseudo-SU(3) symmetry along with its simple symmetry-preserving and symmetry-breaking interactions is presented. This symmetry is a direct consequence of pseudo-spin symmetry which can be clearly seen in a single-particle shell model picture of heavy (A \sbsp{\sim}{\u3e} 100) atomic nuclei. Good pseudo-spin symmetry is shown to have its origin at a more fundamental level by considering relativistic mean field results for the strength parameters of the spin-orbit and the orbit-orbit interactions. As long as the residual interaction is a pseudo-spin scalar interaction, the many-particle extension of the single-particle picture is also expected to have,good total pseudo-spin symmetry. The quadrupole-quadrupole interaction Q${\cdot}Q$ can be approximated by its pseudo spin/space counterpart, $\tilde{Q}{\cdot}\tilde{Q},$ since it is approximately a good pseudo-spin scalar. Within a single major oscillator shell, this interaction possesses SU(3) (to be more precise pseudo-SU(3)) symmetry. As a caveat, the notion of identical bands in normal deformed and superdeformed nuclei can be viewed a consequence of pseudo-SU(3) dynamical symmetry. The pairing interaction, on the other hand, is an exact pseudo-spin scalar; however, it severely breaks SU(3) symmetry. To perform SU(3) shell-model calculations which include a symmetry-breaking interaction like pairing requires SU(3) technologies that consist of two parts: the SU3 and SU3RME packages. Contrary to the traditionally held view that the pairing interaction washes away the deformation, our current results show that the interaction induces triaxial deformed configurations. The combined interaction (known as the pairing-plus-quadrupole model) is systematically studied for even numbers of identical particles (either protons or neutrons) by varying the strength of each term in the interaction. Introducing a quadrupole-quadrupole interaction to a paired system pushes the ground state of the system away from a triaxiai geometry to a more prolate (oblate) one if the number of particles is below (above) the mid-shell. Further studies on the pairing and SU(3) show that the pairing interaction breaks the SU(3) symmetry in a very special way

Hoyle state and rotational features in Carbon-12 within a no-core shell model framework

By using only a fraction of the model space extended beyond current no-core shell-model limits and a schematic effective many-nucleon interaction, we gain additional insight within a symmetry-guided shell-model framework, into the many-body dynamics that gives rise to the ground state rotational band together with phenomena tied to alpha-clustering substructures in the low-lying states in C-12, and in particular, the challenging Hoyle state and its first 2+ excitation. For these states, we offer a novel perspective emerging out of no-core shell-model considerations, including a discussion of associated nuclear shapes and matter radii. This, in turn, provides guidance for ab initio shell models by informing key features of nuclear structure and the interaction.Comment: 5 pages, 4 figure

Evidence for Symplectic Symmetry in Ab Initio No-Core Shell Model Results for Light Nuclei

Clear evidence for symplectic symmetry in low-lying states of $^{12}$C and $^{16}$O is reported. Eigenstates of $^{12}$C and $^{16}$O, determined within the framework of the no-core shell model using the JISP16 $NN$ realistic interaction, typically project at the 85-90% level onto a few of the most deformed symplectic basis states that span only a small fraction of the full model space. The results are nearly independent of whether the bare or renormalized effective interactions are used in the analysis. The outcome confirms Elliott's \SU{3} model which underpins the symplectic scheme, and above all, points to the relevance of a symplectic no-core shell model that can reproduce experimental B(E2) values without effective charges as well as deformed spatial modes associated with clustering phenomena in nuclei.Comment: 4 pages, 3 figures, to be published in Physics Review Letter

Light Nuclei in the Framework of the Symplectic No-core Shell Model

A symplectic no-core shell model (Sp-NCSM) is constructed with the goal of extending the {\it ab-initio} NCSM to include strongly deformed higher-oscillator-shell configurations and to reach heavier nuclei that cannot be studied currently because the spaces encountered are too large to handle, even with the best of modern-day computers. This goal is achieved by integrating two powerful concepts: the {\it ab-initio} NCSM with that of the $\mathrm{Sp}(3,\mathbb{R})\supset\mathrm{SU}(3)$ group-theoretical approach. The NCSM uses modern realistic nuclear interactions in model spaces that consists of many-body configurations up to a given number of $\hbar\Omega$ excitations together with modern high-performance parallel computing techniques. The symplectic theory extends this picture by recognizing that when deformed configurations dominate, which they often do, the model space can be better selected so less relevant low-lying $\hbar\Omega$ configurations yield to more relevant high-lying $\hbar\Omega$ configurations, ones that respect a near symplectic symmetry found in the Hamiltonian. Results from an application of the Sp-NCSM to light nuclei are compared with those for the NCSM and with experiment.Comment: 9 pages, 3 figures, Proceedings of the XXV International Workshop on Nuclear Theory, June 26-July 1, 2006, Rila Mountains, Bulgari

Fermentasi Nira Nipah Menjadi Bioetanol Menggunakan Saccharomyces Cerevisiae dengan Penambahan Urea sebagai Sumber Nitrogen

Nypa is one of biomass wich has a potential to be converted into bioethanol. Bioethanol produced through the process of fermentation of glucose with the help of a microorganism. In this research, nypa sap was converted to be bioethanol using Saccharomyces cerevisiae. The purpose of this researches were doing the fermentation of nypa sap to produce bioethanol, to study the influence of the addition nitrogen source in the fermentation process, and obtain the optimum fermentation time to bioethanol production. The sequances of this research were preparation of material, equipment sterilization, making the starter (inoculum), making the medium fermentation and fermentation process. Fermentation takes place in batches with a volume of 2 liters of fermentation medium. Variation of urea were used 0,2; 0,4; 0,6; and 0,8 g/l, variation of fermentation time were 24, 36, 58, 60, and 72 hours. Temperature fermentation was occured at room temperatur (25 – 30oC). Ethanol concentration was analyzed by using Gas Chromatography. The highest bioethanol concentration was 7,12% at variation of urea 0,6 g/l and fermentation time 36 hours

Fermentasi Larutan Glukosa untuk Produksi Etanol dengan Teknik Immobilisasi Sel Saccharomyces Cerevisiae

Ethanol or ethyl alcohol (C2H5OH) is an organic compound that is very important in the chemical industry and has many benefits in human life. One way of making ethanol is fermentation. Arising problem in the fermentation process is the inhibition of the ethanol product that will damage the structur of the plasma membrane and cause protein denaturation will result in inhibited microbial growth and lower productivity. In this research, the fermentation process of glucose solution with cell immobilization technique to obtain ethanol at higher levels. This research is aimed to study the process of making ethanol with cell immobilization technique and determine the effect of the initial sugar concentration and fermentation time of the acquisition of ethanol. Fermentation takes place in batch reactor with a volume of 2 liters of fermentation medium, heavy beads of 20% (w/v), pH 5,0. The fermentation process of glucose solution was done at various variation of fermentation time i.e 24, 36, 48, 60, 72, 84 and 96 hours and also various variations of concentration of glucose as the intial sugar i.e 100 mg/ml, 125 mg/ml and 150 mg/ml. The process was stired at speed of 200 rpm and temperature of fermentation at room temperature (25 – 30oC). Ethanol concentrations were analyzed using Gas Chromatography. From the result was obtained that the maximum fermentation process is show at glucose concentration of 150 mg/ml and fermentation time of 60 hours with ethanol concentration of 5,149% (v/v) or 40,647 mg/ml

Fermentasi Nira Nipah Menjadi Bioetanol Menggunakan Teknik Immobilisasi Sel Saccharomyces Cerevisiae

The high dependence of fuel resource such as oil, coal, and gas will influence depletion of fossil resources (oil, natural gas, and coal). Therefore, it is important to study conversion of biomass to bioethanol as renewable energy to overcome dependence on fossil fuels. Production of bioethanol using free cell in fermentation and it several disadvantages in separation of yeast cells and biethanol concentration. This research was conducted the fermentation of nypa sap with immobilization cell, using tween 80 and ergosterol as suplement to obtain high concentration of bioethanol as well as avoid osmosis in cells . This work is aimed to study of bioethanol production from nypa sap using immobilized cells, to determine effect of cell immobilization weight and fermentation time to bioethanol, and to obtain maximum conditions on the process. Fermentation was conducted in 2L fermentor having variations of fermentation time such as 24, 36, 48, 60, 72, 84, and 96 hours respectively and cell immobilization weight e.g. 5 %w/v, 10 %w/v, 15 %w/v, and 20 %w/v respectively, and also addition of tween 80 of 0,2% v/v and ergosterol of 0,5 g/l. The concentration of bioethanol was increased with increases of immobilized cells. Maximum conditions of bioethanol production from nypa sap using immobilized cells are shown having cell immobilization weight of 20% w/v and fermentation hours 96th about 17,574 % v/v equal with 138,708 mg/ml

Microscopic description of the elusive Hoyle state

Within a symmetry-guided shell-model framework and using a fraction of the model space extended beyond current no-core shell-model limits along with a schematic effective many-nucleon interaction, we gain new insights into the many-body dynamics that give rise to the ground state and low-lying 0 + states of 12C and 16O. In particular, we gain further understanding of the alpha-clustering nature of the challenging Hoyle state and its first 2+ excitation in 12C, as well as the corresponding states in 16O. This provides guidance for ab initio shell models by informing key features of the underlying nuclear structure and interaction. © Published under licence by IOP Publishing Ltd

ONE STATE TWO SYSTEM : KEDUDUKAN DAN KEWENANGAN PEMERINTAHAN DESA BAH BUTONG 1 DI TENGAH LAHAN HGU DALAM HAL MENCAPAI KESEJAHTERAAN MASYARAKAT

Pengelolaan pemerintahan daerah tentu sebagai bentuk pendelegasian oleh pemerintah kepada desa dalam hal pemberian otonomi guna dapat meningkatkan kesejahteraan masyarakat yang ada di desa. Pengelolaan pemerintahan daerah tentu tidaklah mudah, banyak sekali tantangan dan rintangan, salah satunya tanah HGU. Pemerintahan Desa Bah Butong 1 bertepatan pada wilayah HGU PTPN IV Kabupaten Simalungun, Kecamatan Sidamanik, sering kali mengalami hambatan dalam menjalankan kebijakan dan programnya demi menyejahterakan rakyat terhadap kawasan HGU PTPN IV, semisal ingin memperbaiki akses jalan dan membuat jalan untuk masuknya air dengan melakukan pengeboran sumur. Hal-hal semacam itu tentu akan sulit dalam hal mengambil kebijakan dan menjalankan program yang dilakukan oleh Pemerintahan Desa Bah Butong 1 yang notabenenya menyejahterakan rakyat, yang mana harus mendapatkan izin terlebih dahulu dari mereka. Pada penelitian ini penulis menggunakan jenis penelitian yuridis normatif (legal research) karena berkaitan dengan judul yang penulis angkat yaitu “Kedudukan dan Kewenangan Pemerintahan Desa Bah Butong 1 Di Tengah Lahan HGU PTPN IV Dalam Hal Mencapai Kesejahteraan Masyarakat”. Metode penelitian yuridis normatif merupakan penelitian hukum kepustakaan yang dilaksanakan dengan cara menggali bahan-bahan kepustakaan atau dapat disebut dengan istilah data sekunder belaka. Teknik pengumpulan data yang digunakan adalah studi kepustakaan (library research) yaitu secara langsung dengan mengunjungi perpustakaan (baik di dalam kampus Universitas Islam Negeri Sumatera Utara maupun di luar kampus), serta pengumpulan data pada penelitian ini juga dilakukan dengan cara searching melalui media internet guna mengumpulkan data skunder yang diperlukan pada penelitian ini