4,408 research outputs found
Mass imbalance effect in resonant Bose-Fermi mixtures
We consider a homogeneous Bose-Fermi mixture, with the boson-fermion
interaction tuned by a Fano-Feshbach resonance, in the presence of mass and
density imbalance between the two species. By using many-body diagrammatic
methods, we first study the finite-temperature phase diagram for the specific
case of the mass-imbalanced mixture Rb K for different values of
the density imbalance. We then analyse the quantum phase transition associated
with the disappearance at zero temperature of the boson condensate above a
critical boson-fermion coupling. We find a pronounced dependence of the
critical coupling on the mass ratio and a weak dependence on the density
imbalance. For a vanishingly small boson density, we derive, within our
approximation, the asymptotic expressions for the critical coupling in the
limits of small and large mass ratios. These expressions are relevant also for
the polaron-molecule transition in a Fermi mixture at small and large mass
ratios. The analysis of the momentum distribution functions at sufficiently
large density imbalances shows an interesting effect in the bosonic momentum
distribution due to the simultaneous presence of composite fermions and
unpaired fermions.Comment: Final versio
Geometry of unsteady fluid transport during fluidâstructure interactions
We describe the application of tools from dynamical systems to define and quantify the unsteady fluid transport that occurs during fluidâstructure interactions and in unsteady recirculating flows. The properties of Lagrangian coherent structures (LCS) are used to enable analysis of flows with arbitrary time-dependence, thereby extending previous analytical results for steady and time-periodic flows. The LCS kinematics are used to formulate a unique, physically motivated definition for fluid exchange surfaces and transport lobes in the flow. The methods are applied to numerical simulations of two-dimensional flow past a circular cylinder at a Reynolds number of 200; and to measurements of a freely swimming organism, the Aurelia aurita jellyfish. The former flow provides a canonical system in which to compare the present geometrical analysis with classical, Eulerian (e.g. vortex shedding) perspectives of fluidâstructure interactions. The latter flow is used to deduce the physical coupling that exists between mass and momentum transport during self-propulsion. In both cases, the present methods reveal a well-defined, unsteady recirculation zone that is not apparent in the corresponding velocity or vorticity fields. Transport rates between the ambient flow and the recirculation zone are computed for both flows. Comparison of fluid transport geometry for the cylinder crossflow and the self-propelled swimmer within the context of existing theory for two-dimensional lobe dynamics enables qualitative localization of flow three-dimensionality based on the planar measurements. Benefits and limitations of the implemented methods are discussed, and some potential applications for flow control, unsteady propulsion, and biological fluid dynamics are proposed
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Dynamic Phase Diagram of Catalytic Surface of Hexagonal Boron Nitride under Conditions of Oxidative Dehydrogenation of Propane.
Partially oxidized surfaces of hexagonal boron nitride (hBN) and several metal borides are unexpectedly excellent catalysts for oxidative dehydrogenation of alkanes to olefins, but the nature of the active site(s) on these B-containing interfaces remains elusive. We characterize the surface of the partially oxidized B-rich hBN surface under reaction conditions from first principles. The interface has thermal access to multiple different stoichiometries and multiple structures of each stoichiometry. The size of the thermal ensemble is composition-dependent. The phase diagram of the interface constructed on the basis of the statistical ensembles of many accessible states is very different from the one based on global minima. Phase boundaries shift and blur, and phases consist of several stoichiometries and structures. The BO layer transiently exposes the reactive -BâO motifs in the metastable states. The fluxionality and structural diversity emerging under reaction conditions must be taken into account in theoretically descriptions of the catalytic interface
Disfemisme pada Wacana Lingkungan: sebuah Kajian Ekolinguistik Kritis dalam Media Massa di Indonesia
Media massa menggunakan berbagai piranti bahasa untuk mengemas ideologi konstruktif dan destruktif terkait dengan lingkungan, misalnya eufemisme dan disfemisme. Penelitian ini berusaha mengkaji permasalahan kebahasaan yang terdapat dalam wacana lingkungan dalam media massa di Indonesia, yakni mengenai disfemisme. Penelitian ini merupakan penelitian deskriptif kualitatif. Data dikumpulkan dari majalah Gatra, Tempo, Trust, harian Kompas, Kabar Indonesia, Media Indonesia, Suara Merdeka, dan Surabaya Pagi, portal Antara, Vivanews, Detiknews, Metronews, dan Okezone menggunakan metode simak, dengan teknik lanjutan berupa teknik catat. Namun, data tersebut dibatasi hanya seputar permasalahan tentang polusi, pencemaran, dan reservasi lingkungan. Analisis data dilakukan menggunakan metode agih dan metode padan dengan teknik lanjutan berupa teknik substitusi dan parafrase. Bentuk satuan ekspresi disfemisme yang digunakan oleh media massa di Indonesia pada wacana lingkungan ada empat macam, yaitu kata, frase, klausa, dan kalimat. Satuan ekspresi yang berbentuk kata, yaitu berupa kata dasar, kata turunan dan kata majemuk.Satuan ekspresi disfemisme berbentuk kata turunan, yaitu kata turunan berkategori nomina, verba, dan ajektiva. Satuan ekspresi disfemisme yang berbentuk frase, yaitu frase nomina, frase ajektiva, dan frase verba. Referensi disfemisme yang ditemukan berkaitan dengan manusia, tumbuhan, binatang, tanah, nuklir dan material beracun, sampah dan limbah, polusi, Perusakan habitat alami, kepunahan spesies, dan tabu. Fungsi-fungsi satuan ekspresi disfemisme ada dua belas macam, yaitu (1) mengungkapkan kemarahan atau kejengkelan, (2) mengkritik, (3) menyindir, (4) menuduh atau menyalahkan, (5) mengeluh, (6) menyampaikan informasi, (7) menghina, mengejek atau mempertajam penghinaan, (8) memperingatkan, (9) menunjukkan ketidaksetujuan, (10) menunjukkan rasa tidak suka, (11) melebih-lebihkan, dan (12) menunjukkan bukti
Kajian Psikologi Sastra Dan Nilai Pendidikan Karakter Novel Ibuk Karya Iwan Setyawan Serta Relevansinya Sebagai Bahan Ajar Dalam Pembelajaran Bahasa Dan Sastra Indonesia Di SMP
: The purposes of this study are to describe: (1) the intrinsic elements of novel Ibuk by Iwan Setyawan; (2) the psychological aspects of the characters; (3) the values of character education in the novel Ibuk; and (4) the relevance of novel Ibuk as materials in the Indonesian language and literature study in junior high school. This research was conducted with qualitative methods and contents analysis approach. Conclusions of this thesis are (1) the intrinsic structure of novel Ibuk includes theme, plot, characters, setting, point of view, dialogue, story-telling style and speeches; (2) as the human characters in the novel Ibuk have the common of goods for survival; (3) the story in the novel Ibuk contains values character education; and (4) novel Ibuk is relevant novel was made in Indonesian Language learning materials
Peranan Pelatihan Dalam Peningkatan Kinerja Karyawan (Studi Kasus Bagian Operasional PT Pln (Persero) Pembangkitan Sumatera Selatan Bagian Selatan)
This research to know the Role of training to improvement of the employees performance (case study at operational division at PT PLN (Persero) Pembangkitan Sumatera Bagian Selatan with the research problem how is the role of training through the improvement of the employees performance at operational division at PT PLN (Persero) Pembangkitan Sumatera Bagian Selatan. The writer used primary data that were collected from the result of intervew to the HRD Manager, and shared the questionnaries to 23 employees which already got the training at operational division and secondary data that were collected from literature like books, journal and the official website of PT PLN (Persero). The data analyzed by using qualitative descriptive and quantitative technique with the calculation of the questionnaries result were using percentage formula. Writer found that the training program in operational division at PT PLN (Persero) Pembangkitan Sumatera Bagian Selatan was good and in accordance with the requirements of the employees and improvement of the employees performance, and after joined the training the employees could increase their team work. So the training program was very important in the improvement of the employees performance. Writer suggests PT PLN (Persero) Pembangkitan Sumatera bagian Selatan especially in operational division to keep the traning program because it is very important to the improvement of the employees performance that can impact the qualityof human resources for the improvement of the company and PT PLN (Persero) also should concern to the material and facility that were provided because there were a few employees that still disagree with that
Metode Pengajaran Mile Wenhuaban di Maha Vihara dan Pusdiklat Buddha Maitreya Surabaya
Pengajaran bahasa Mandarin secara non formal sekarang telah banyak dibuka di Surabaya, salah satunya adalah kelas MiLe WenHuaBan. Dalam pengajaran bahasa Mandarin sebagai bahasa asing, metode pengajaran yang strategis, aktivitas dan lingkungan dapat mendukung perkembangan bahasa sasaran murid. Oleh karena itu, tujuan dari penelitian ini adalah untuk mengetahui efektivitas metode pengajaran di MiLe WenHuaBan, serta mengetahui kelebihan kekurangan metode pengajaran MiLe WenHuaBan. Metode penelitian yang digunakan adalah observasi, wawancara dan memberikan tes HSK. Dari hasil analisis, penulis menemukan bahwa dalam pengajaran kelas ini, cukup efektif dalam belajar bahasa Mandarin tingkat dasar, murid-murid telah terbiasa berbicara bahasa Mandarin, dan dalam kurun waktu empat bulan murid-murid telah dapat lulus tes HSK level tiga. Demi meningkatkan kualitas pengajaran, masih ada hal yang harus ditingkatkan, seperti latihan keterampilan menulis
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