391 research outputs found
Nonlinear metal-dielectric nanoantennas for light switching and routing
We introduce a novel hybrid metal-dielectric nanoantenna composed of
dielectric (crystalline silicon) and metal (silver) nanoparticles. A
high-permittivity dielectric nanoparticle allows to achieve effective light
harvesting, and nonlinearity of a metal nanoparticle controls the radiation
direction. We show that the radiation pattern of such a nanoantenna can be
switched between the forward and backward directions by varying only the light
intensity around the level of 11 MW/cm, with the characteristic switching
time of 260 fs.Comment: 9 pages, 5 figures, submitted to New J. Phy
Subwavelength modulational instability and plasmon oscillons in nanoparticle arrays
We study modulational instability in nonlinear arrays of subwavelength
metallic nanoparticles, and analyze numerically nonlinear scenarios of the
instability development. We demonstrate that modulational instability can lead
to the formation of regular periodic or quasi-periodic modulations of the
polarization. We reveal that such nonlinear nanoparticle arrays can support
long-lived standing and moving oscillating nonlinear localized modes - plasmon
oscillons.Comment: 5 pages, 5 figures, published in Physical Review Letter
Subwavelength plasmonic kinks in arrays of metallic nanoparticles
We analyze nonlinear effects in optically driven arrays of nonlinear metallic
nanoparticles. We demonstrate that such plasmonic systems are characterized by
a bistable response, and they can support the propagation of dissipative
switching waves (or plasmonic kinks) connecting the states with different
polarization. We study numerically the properties of such plasmonic kinks which
are characterized by a subwavelength extent and a tunable velocity.Comment: 6 pages, 5 figures, published in Opt. Expres
Birefringent left-handed metamaterials and perfect lenses
We describe the properties of birefringent left-handed metamaterials and
introduce the concept of a birefringent perfect lens. We demonstrate that, in a
sharp contrast to the conventional left-handed perfect lens at
, where is the dielectric constant and is the
magnetic permeability, the birefringent left-handed lens can focus either TE or
TM polarized waves or both of them, allowing a spatial separation of the TE and
TM images. We discuss several applications of the birefringent left-handed
lenses such as the beam splitting and near-field diagnostics at the
sub-wavelength scale.Comment: 4 pages 6 figure
ΠΠ½Π΅ΡΠ½ΡΡ ΡΡΠ΅Π΄Π° ΠΊΠ°ΠΊ ΡΠ°ΠΊΡΠΎΡ Π²ΡΠ±ΠΎΡΠ° ΠΌΠ΅ΡΡΠ° ΠΏΡΠΎΠΆΠΈΠ²Π°Π½ΠΈΡ
Many people have certain problems with the choice of the place of living. The main idea of this article is to study the aspects of urban area environment which effect on this decision. The influence of these factors is analyzed on example of two cities: the big one and the small one.ΠΠ½ΠΎΠ³ΠΈΠ΅ Π»ΡΠ΄ΠΈ ΠΈΠΌΠ΅ΡΡ ΠΎΠΏΡΠ΅Π΄Π΅Π»Π΅Π½Π½ΡΠ΅ ΠΏΡΠΎΠ±Π»Π΅ΠΌΡ ΠΏΡΠΈ Π²ΡΠ±ΠΎΡΠ΅ ΠΌΠ΅ΡΡΠ° ΠΆΠΈΡΠ΅Π»ΡΡΡΠ²Π°. ΠΡΠ½ΠΎΠ²Π½ΠΎΠΉ ΠΈΠ΄Π΅Π΅ΠΉ Π΄Π°Π½Π½ΠΎΠΉ ΡΡΠ°ΡΡΠΈ ΡΠ²Π»ΡΠ΅ΡΡΡ ΠΈΠ·ΡΡΠ΅Π½ΠΈΠ΅ Π°ΡΠΏΠ΅ΠΊΡΠΎΠ² Π³ΠΎΡΠΎΠ΄ΡΠΊΠΎΠΉ ΠΎΠΊΡΡΠΆΠ°ΡΡΠ΅ΠΉ ΡΡΠ΅Π΄Ρ, ΠΊΠΎΡΠΎΡΡΠ΅ Π²Π»ΠΈΡΡΡ Π½Π° Π²ΡΠ±ΠΎΡ ΠΌΠ΅ΡΡΠ° ΠΏΡΠΎΠΆΠΈΠ²Π°Π½ΠΈΡ Π»ΡΠ΄Π΅ΠΉ. ΠΠ»ΠΈΡΠ½ΠΈΠ΅ ΡΡΠΈΡ
ΡΠ°ΠΊΡΠΎΡΠΎΠ² Π°Π½Π°Π»ΠΈΠ·ΠΈΡΡΠ΅ΡΡΡ Π½Π° ΠΏΡΠΈΠΌΠ΅ΡΠ΅ Π΄Π²ΡΡ
Π³ΠΎΡΠΎΠ΄ΠΎΠ²: ΠΎΠ΄ΠΈΠ½ Π±ΠΎΠ»ΡΡΠΎΠΉ ΠΈ ΠΎΠ΄ΠΈΠ½ ΠΌΠ°Π»Π΅Π½ΡΠΊΠΈΠΉ ΠΏΠΎ Π³ΡΠ°Π΄ΠΎΡΡΡΠΎΠΈΡΠ΅Π»ΡΠ½ΠΎΠΉ ΠΊΠ»Π°ΡΡΠΈΡΠΈΠΊΠ°ΡΠΈΠΈ
Penentuan Status Hara Nitrogen pada Bibit Duku
Nitrogen merupakan unsur yang sangat memengaruhi pertumbuhan, perkembangan dan produksi tanaman. Hara ini merupakan komponen esensial klorofil, protein, hormon, dan enzim. Gejala kekurangan atau kelebihan hara tersebut dapat terdeteksi secara visual pada penampilan daun, sehingga sangat penting untuk mencegah terjadinya kedua kondisi tersebut pada pertumbuhan bibit duku (Lansium domesticum Corr). Penelitian status hara nitrogen dilakukan pada bibit duku umur 2 tahun yang ditanam pada media pasir di Provinsi Jambi dari bulan Maret 2010 sampai dengan Maret 2011. Percobaan disusun menggunakan rancangan acak kelompok, dengan lima perlakuan dosis nitrogen: 0, 100, 200, 400, dan 800 ppm/tanaman, diaplikasikan dalam bentuk air irigasi setiap 2 hari sekali dan masing-masing perlakuan terdiri dari tiga tanaman dan tiga ulangan. Hasil penelitian menunjukkan bahwa gejala kekurangan nitrogen pertama terlihat pada daun tua yang ditandai dengan Perubahan warna daun menjadi hijau kekuningan (klorosis), tangkai daun lemah dan berwarna kuning, jumlah daun kurang atau sama dengan 4,2 helai, pertumbuhan terhambat, dan konsentrasi nitrogen daun kurang dari 1,13%. Kecukupan nitrogen ditandai dengan pertumbuhan yang normal, daun berwarna hijau tua, jumlah daun berkisar antara 5 sampai 5,5 helai dan konsentrasi nitrogen daun antara 1,13 sampai 1,44%. Kelebihan nitrogen terlihat pada daun yang berwarna coklat dan mengalami nekrosis, jumlah daun kurang dari 3,78 helai, pertumbuhan bibit terhambat, konsentrasi nitrogen daun lebih dari 1,44%. Pertumbuhan maksimum membutuhkan 381 ppm pupuk nitrogen/tanaman, yang setara dengan 8 g urea/l air atau 77 g Urea/tahun. Rekomendasi pemupukan N ini merupakan salah satu teknologi yang dapat meningkatkan ketersediaan bibit duku bermutu
Hydrobionts of a freshwater oil-polluted northern lake: bioaccumulation of heavy metals in fish and the rate of ecosystem recovery
The response of phytoplankton, zooplankton, benthic and fish community structure to one of the biggest oil spill in history of Komi Republic (north-west part of Russia) was investigated using data from a long-term survey off the polluted lake. The characteristics of aquatic freshwater communities observed in the study area 10, 11 and 22 years after the spill (1994) were compared to find out the rate of natural recovery of the ecosystem after oil decontamination of bottom sediments. The concentrations of fifteen trace metals (Al, Cr, Fe, Co, Ni, Cu, Zn, As, Mo, Cd, Sb, Pb, U, Bi, Th) were analyzed in the tissues (muscle) of three fish species. The concentrations of Al (3-309 mg/kg), Cr (0,1-3,71 mg/kg), Fe (8,6-317 mg/kg), and Cu (0,09-99 mg/kg) in fishes from polluted lake resulted in most cases higher than reference thresholds. Quantitative and qualitative indicators of aquatic invertebrates from polluted lake reach those one of unpolluted lake but do not fully recover 22 years after the spill, despite that oil concentration in water column and in bottom sediments was lower than reference tresholds. We conclude that natural recovery rate of aquatic freshwater ecosystems in northern regions after oil pollution is extremely low. The purification of water and bottom sediments of oil-polluted northern water bodies is necessary for stimulation of ecosystem restoration
ΠΡΠ΅Π΄Π²Π°ΡΠΈΡΠ΅Π»ΡΠ½Π°Ρ ΠΎΡΠ΅Π½ΠΊΠ° ΡΠ½Π΅ΡΠ³ΠΎΡΡΡΠ΅ΠΊΡΠΈΠ²Π½ΠΎΡΡΠΈ Π·Π΄Π°Π½ΠΈΠΉ Π²Β ΡΡΠ»ΠΎΠ²ΠΈΡΡ ΡΠ΅Π·ΠΊΠΎ ΠΊΠΎΠ½ΡΠΈΠ½Π΅Π½ΡΠ°Π»ΡΠ½ΠΎΠ³ΠΎ ΠΊΠ»ΠΈΠΌΠ°ΡΠ°
Construction of energy-efficient buildings becomes a top priority for many countries. Yet certain obstacles in achieving internal environment comfort standards remain in regions with extreme continental climate. In addition to engineering and economic challenges, there exist design process issues since design data should closely correspond with resulting performance of the building. This paper focuses on accurate energy demand estimation during design stage. Two types of buildings designed for Ural-Siberian region of Russia and for Kazakhstan are examined: detached and medium-rise apartment buildings. Most influential factors are taken into consideration and general recommendations on improving energy efficiency using effective combination of structural and engineering solutions are given. Adaptation of design procedure in terms of extreme continental climate made by means of simplified but precise Passive House planning tool is demonstrated.Π‘ΡΡΠΎΠΈΡΠ΅Π»ΡΡΡΠ²ΠΎ ΡΠ½Π΅ΡΠ³ΠΎΡΡΡΠ΅ΠΊΡΠΈΠ²Π½ΡΡ
Π·Π΄Π°Π½ΠΈΠΉ ΡΠ²Π»ΡΠ΅ΡΡΡ ΠΏΡΠΈΠΎΡΠΈΡΠ΅ΡΠ½ΡΠΌ Π½Π°ΠΏΡΠ°Π²Π»Π΅Π½ΠΈΠ΅ΠΌ Π΄Π»Ρ ΠΌΠ½ΠΎΠ³ΠΈΡ
ΡΡΡΠ°Π½. ΠΠ΄Π½Π°ΠΊΠΎ Π² ΡΠ΅Π³ΠΈΠΎΠ½Π°Ρ
Ρ ΡΡΡΠΎΠ²ΡΠΌ ΠΊΠ»ΠΈΠΌΠ°ΡΠΎΠΌ ΡΠ°ΡΡΠΎ Π²ΠΎΠ·Π½ΠΈΠΊΠ°ΡΡ ΠΏΡΠΎΠ±Π»Π΅ΠΌΡ Π΄ΠΎΡΡΠΈΠΆΠ΅Π½ΠΈΡ Π½ΠΎΡΠΌΠ°ΡΠΈΠ²Π½ΡΡ
ΠΏΠΎΠΊΠ°Π·Π°ΡΠ΅Π»Π΅ΠΉ ΠΊΠΎΠΌΡΠΎΡΡΠ° Π²Π½ΡΡΡΠ΅Π½Π½Π΅ΠΉ ΡΡΠ΅Π΄Ρ. Π ΠΈΠ΄Π΅Π°Π»Π΅ ΠΏΡΠΎΠ΅ΠΊΡΠ½ΡΠ΅ Π·Π½Π°ΡΠ΅Π½ΠΈΡ ΠΏΠΎΡΡΠ΅Π±Π½ΠΎΡΡΠ΅ΠΉ Π² ΡΠ»Π΅ΠΊΡΡΠΎΡΠ½Π΅ΡΠ³ΠΈΠΈ Π½Π° ΠΎΡΠΎΠΏΠ»Π΅Π½ΠΈΠ΅ ΠΈ ΠΊΠΎΠ½Π΄ΠΈΡΠΈΠΎΠ½ΠΈΡΠΎΠ²Π°Π½ΠΈΠ΅ Π·Π΄Π°Π½ΠΈΡ Π΄ΠΎΠ»ΠΆΠ½Ρ ΡΠΎΡΠ½ΠΎ ΡΠΎΠΎΡΠ²Π΅ΡΡΡΠ²ΠΎΠ²Π°ΡΡ ΠΈΡΠΎΠ³ΠΎΠ²ΡΠΌ ΠΏΠΎΠΊΠ°Π·Π°ΡΠ΅Π»ΡΠΌ. Π ΡΡΠΎΠΉ ΡΡΠ°ΡΡΠ΅ ΡΠ°ΡΡΠΌΠ°ΡΡΠΈΠ²Π°ΡΡΡΡ ΠΌΠ΅ΡΠΎΠ΄ΠΈΠΊΠΈ ΡΠΎΡΠ½ΠΎΠ³ΠΎ ΠΏΡΠΎΠ³Π½ΠΎΠ·ΠΈΡΠΎΠ²Π°Π½ΠΈΡ ΡΠ½Π΅ΡΠ³ΠΎΠΏΠΎΡΡΠ΅Π±Π»Π΅Π½ΠΈΡ Π½Π° ΡΡΠ°Π΄ΠΈΠΈ ΠΏΡΠΎΠ΅ΠΊΡΠΈΡΠΎΠ²Π°Π½ΠΈΡ. ΠΡΡΠ»Π΅Π΄ΠΎΠ²Π°Π½ΠΎ Π΄Π²Π° ΡΠΈΠΏΠ° Π·Π΄Π°Π½ΠΈΠΉ, ΠΏΡΠΎΠ΅ΠΊΡΠΈΡΡΠ΅ΠΌΡΡ
Π΄Π»Ρ Π£ΡΠ°Π»ΠΎ-Π‘ΠΈΠ±ΠΈΡΡΠΊΠΎΠ³ΠΎ ΡΠ΅Π³ΠΈΠΎΠ½Π° Π ΠΎΡΡΠΈΠΈ ΠΈ ΠΠ°Π·Π°Ρ
ΡΡΠ°Π½Π°: ΠΈΠ½Π΄ΠΈΠ²ΠΈΠ΄ΡΠ°Π»ΡΠ½ΡΠΉ Π΄ΠΎΠΌ ΠΈ ΠΌΠ½ΠΎΠ³ΠΎΠΊΠ²Π°ΡΡΠΈΡΠ½ΡΠΉ Π΄ΠΎΠΌ ΡΡΠ΅Π΄Π½Π΅ΠΉ ΡΡΠ°ΠΆΠ½ΠΎΡΡΠΈ. ΠΠ°Π½Ρ ΡΠ΅ΠΊΠΎΠΌΠ΅Π½Π΄Π°ΡΠΈΠΈ ΠΏΠΎ ΡΠ½ΠΈΠΆΠ΅Π½ΠΈΡ ΡΠ½Π΅ΡΠ³ΠΎΠΏΠΎΡΡΠ΅Π±Π»Π΅Π½ΠΈΡ Π·Π΄Π°Π½ΠΈΠΉ ΠΏΡΡΠ΅ΠΌ ΡΡΡΠ΅ΠΊΡΠΈΠ²Π½ΠΎΠ³ΠΎ ΡΠΎΡΠ΅ΡΠ°Π½ΠΈΡ ΠΊΠΎΠ½ΡΡΡΡΠΊΡΠΈΠ²Π½ΡΡ
ΠΈ ΠΈΠ½ΠΆΠ΅Π½Π΅ΡΠ½ΡΡ
ΡΠ΅ΡΠ΅Π½ΠΈΠΉ. ΠΠΎΠΊΠ°Π·Π°Π½ ΡΡΠ΅Ρ ΠΎΡΠ½ΠΎΠ²Π½ΡΡ
ΡΠ°ΠΊΡΠΎΡΠΎΠ², Π²Π»ΠΈΡΡΡΠΈΡ
Π½Π° ΡΠ½Π΅ΡΠ³Π΅ΡΠΈΡΠ΅ΡΠΊΠΈΠΉ Π±Π°Π»Π°Π½Ρ Π·Π΄Π°Π½ΠΈΠΉ. ΠΠ° ΠΏΡΠΈΠΌΠ΅ΡΠ΅ ΠΠ°ΠΊΠ΅ΡΠ° ΠΏΡΠΎΠ΅ΠΊΡΠΈΡΠΎΠ²Π°Π½ΠΈΡ ΠΏΠ°ΡΡΠΈΠ²Π½ΠΎΠ³ΠΎ Π΄ΠΎΠΌΠ° 2007 ΠΏΡΠΈΠ²Π΅Π΄Π΅Π½ ΠΏΡΠΈΠΌΠ΅Ρ Π°Π΄Π°ΠΏΡΠ°ΡΠΈΠΈ ΡΠΏΡΠΎΡΠ΅Π½Π½ΠΎΠΉ, Π½ΠΎ Π΄ΠΎΡΡΠ°ΡΠΎΡΠ½ΠΎ ΡΠΎΡΠ½ΠΎΠΉ ΠΌΠ΅ΡΠΎΠ΄ΠΈΠΊΠΈ ΡΠ°ΡΡΠ΅ΡΠ° ΠΊ ΡΠ΅Π·ΠΊΠΎ ΠΊΠΎΠ½ΡΠΈΠ½Π΅Π½ΡΠ°Π»ΡΠ½ΡΠΌ ΠΊΠ»ΠΈΠΌΠ°ΡΠΈΡΠ΅ΡΠΊΠΈΠΌ ΡΡΠ»ΠΎΠ²ΠΈΡΠΌ
Method for vibration measurement in pipelines of residential buildings
The article is devoted to the problem of insufficiency and incompleteness of existing methods for measuring vibration in pipelines of residential buildings. Existing methods for measuring vibrations in pipelines are considered and their effectiveness is analyzed. The assessment of complexity, cost efficiency and accuracy of the existing vibration measurement methods is made. An improved method for measuring the vibration of a pipeline section with a tap based on the analysis of the trace of blurring a circular mark and the Doppler Effect is proposed. Β© Published under licence by IOP Publishing Ltd
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