M-theory on `toric' G_2 cones and its type II reduction

We analyze a class of conical G_2 metrics admitting two commuting isometries, together with a certain one-parameter family of G_2 deformations which preserves these symmetries. Upon using recent results of Calderbank and Pedersen, we write down the explicit G_2 metric for the most general member of this family and extract the IIA reduction of M-theory on such backgrounds, as well as its type IIB dual. By studying the asymptotics of type II fields around the relevant loci, we confirm the interpretation of such backgrounds in terms of localized IIA 6-branes and delocalized IIB 5-branes. In particular, we find explicit, general expressions for the string coupling and R-R/NS-NS forms in the vicinity of these objects. Our solutions contain and generalize the field configurations relevant for certain models considered in recent work of Acharya and Witten.Comment: 45 pages, references adde

Fermentația anaerobă a gunoiului de pasăre cu inocul de nămol activat în combinație cu tratarea prin electroliză

The aim of the work was to study the effect of electrolysis on the process of anaerobic digestion in the example of poultry manure with an inoculum of activated sludge from a municipal wastewater treatment plant. The set aim was achieved by solving the following tasks: microcopy of anaerobic activated sludge during the digestion of poultry manure under the influence of electrolysis treatment; studying the dynamics of biogas yield and its component composition under electrolysis treatment; studying the change in pH values and redox potential (ORP) in experiments with a combination of a bioreactor with electrolysis treatment and without treatment. Evaluation of the effect of stimulating the metabolic activity of microorganisms during treatment in the bioreactor-electrolyser was the most significant result. In addition, improved biodegradability of complex organic components of poultry manure was substantiated. Thus, methane yield on the 28th day was 640.5 ml from the total volume of 1525 ml of biogas, and under conventional conditions, methane yield was 33.4 ml from 50 ml of total volume. The decrease of H2S content in biogas under the influence of electrolysis was determined. A low ORP value of - 495 mV was achieved in the control experiment (without electrolysis treatment). ORP gradually increased in the bioreactor-electrolyser at all stages of digestion and reached - 53 mV on day 28. pH stabilized at a neutral level. The positive effect of combining anaerobic digestion with electrolysis on the intensification of biogas production with a large volume of methane has been experimentally confirmed.Целью работы является изучение эффектов электролизного воздействии в процессе анаэробного сбраживания, на примере птичьего помета с инокулятом активного ила с городских очистных сооружений. Поставленная цель достигается за счет решения следующих задач: микрокопирование анаэробного активного ила в процессе сбраживания птичьего помета при воздействии на него электролизной обработки; изучение динамики выхода биогаза и его компонентного состава при электролизной обработке; изучение изменения значений рН и окислительно-восстановительного потенциала (ОВП) в экспериментах с комбинацией биореактора с электролизной обработкой и без обработки. Наиболее существенным результатом является определение в процессе обработки в биореакторе-электролизере эффекта стимулирования метаболической активности эколого-трофических групп микроорганизмов с получением большего количества биогаза при поступлении экзогенного водорода и улучшении биодеградируемости сложных органических компонентов птичьего помета, так его объем выхода составил на 28 сутки 640,5 мл метана из 1525 мл, а в стандартных условиях уже на 28 сутки выход биогаза было 33,4 мл метана из 50 мл общего объема. Также выявлено значительное уменьшения H2S в биогазе при воздействии электролиза, а именно более чем в 10 раз в сравнении со стандартными условиями анаэробного сбраживания. При этом в контрольном эксперименте (без электролизной обработки) достигалось низкое значение ОВП до - 495 мВ, в биореакторе электролизере ОВП постепенно возрастало в течение всех этапов сбраживания и на 28 сутки приобрело значение - 53 мВ, рН стабилизировалось на нейтральном уровне. Значимость полученных результатов состоит в том, что экспериментально подтвердили положительный эффект комбинации анаэробного сбраживания с электролизной обработки на интенсификацию производство биогаза с большим объемом метана, а именно электрический разряд, воздействуя на рост метанообразующих микроорганизмов, позволяет получить энергию за счет восстановления CO2 до метана, при этом как акцептор электронов выступает экзогенный Н2.Scopul lucrării este de a studia efectele electrolizei în procesul de fermentație anaerobă, pe exemplul gunoiului de pasăre cu inocul de nămol activat provenit de la stațiile municipale de epurare a apelor uzate. Scopul stabilit este atins prin rezolvarea următoarelor sarcini: microcopierea nămolului activat anaerob în timpul fermentației gunoiului de pasăre sub influența tratării prin electroliză; studiul dinamicii randamentului biogazului și al compoziției componentelor acestuia în timpul tratării prin electroliză; studiul modificărilor pH-ului și a potențialului Redox (ORP) în experimentele cu combinația de bioreactor cu tratare prin electroliză și fără tratare. Cel mai semnificativ rezultat a fost acela, că în timpul tratării în electrolizatorul bioreactorului, biodegradabilitatea componentelor organice ale substratului s-a îmbunătățit, ceea ce a dus la obținerea unei cantități sporite biogaz, astfel încât producția de biogaz a fost de 1525 ml în ziua 28 din 640,5 ml de metan, iar în condiții standard, deja în ziua 28, producția de biogaz a scăzut semnificativ la 50 ml, din care 33,4 ml de metan. În același timp, în experimentul de control (fără tratare prin electroliză) s -a atins o valoare scăzută a ORP de până la -495 mV, în timp ce în electrolizatorul bioreactorului ORP a crescut treptat în timpul tuturor etapelor de fermentație, iar în a 28-a zi a ajuns la - 53 mV, valoarea pH-ului s-a stabilizat la un nivel neutru. Semnificația rezultatelor obținute constă în faptul, că a fost confirmat experimenta l efectul pozitiv al furnizării suplimentare de hidrogen exogen în timpul tratării prin electroliză asupra intensificării producției de biogaz, precum și faptul că această tratare a contribuit la eliminarea agenților patogeni, obținându-se nămoluri solide sigure, care pot fi utilizate ulterior ca biofertilizator pentru agricultură

Selective quantum evolution of a qubit state due to continuous measurement

We consider a two-level quantum system (qubit) which is continuously measured by a detector. The information provided by the detector is taken into account to describe the evolution during a particular realization of measurement process. We discuss the Bayesian formalism for such ``selective'' evolution of an individual qubit and apply it to several solid-state setups. In particular, we show how to suppress the qubit decoherence using continuous measurement and the feedback loop.Comment: 15 pages (including 9 figures

Quasi freestanding graphene on SiC 0001 via cobalt intercalation of zero layer graphene

Modification of the electronic and crystal structure of zero layer graphene grown on 6H SiC 0001 after Co intercalation is reported. Using a wide range of techniques including angle resolved photoelectron spectroscopy, x ray photoelectron spectroscopy, Raman spectroscopy, low energy electron diffraction, we found that zero layer graphene on SiC transforms into graphene monolayer as a result of cobalt intercalation. The Dirac cone of amp; 960; band characteristic of quasi freestanding graphene is observed. In combination with high resolution transmission electron microscopy and atomic force microscopy data, we conclude that ultrathin silicide CoSi CoSi2 structure is formed between graphene and SiC substrate. Investigation of magnetic properties reveals ferromagnetic behavior with open hysteresis loop. The results of this work are the basis for further implementation of magneto spin orbit graphene on a semiconducting substrate and are important for the future application of such graphene in spintronic

Domain walls of N=2 supergravity in five dimensions from hypermultiplet moduli spaces

We study domain wall solutions in d=5, N=2 supergravity coupled to a single hypermultiplet whose moduli space is described by certain inhomogeneous, toric ESD manifolds constructed recently by Calderbank and Singer. Upon gauging a generic U(1) isometry of these spaces, we obtain an infinite family of models whose "superpotential" admits an arbitrary number of isolated critical points. By investigating the associated supersymmetric flows, we prove the existence of domain walls of Randall-Sundrum type for each member of our family, and find chains of domain walls interpolating between various AdS_5 backgrounds. Our models are described by a discrete infinity of smooth and complete one-hypermultiplet moduli spaces, which live on an open subset of the minimal resolution of certain cyclic quotient singularities. These spaces generalize the Pedersen metrics considered recently by Behrndt and Dall' Agata.Comment: 39 pages, numerous figures; v4: two references adde

Study of KS KL Coupled Decays and KL -Be Interactions with the CMD-2 Detector at VEPP-2M Collider

The integrated luminosity about 4000 inverse nanobarn of around phi meson mass ( 5 millions of phi mesons) has been collected with the CMD-2 detector at the VEPP-2M collider. A latest analysis of the KS KL coupled decays based on 30 % of available data is presented in this paper. The KS KL pairs from phi meson decays were reconstructed in the drift chamber when both kaons decayed into two charged particles. From a sample of 1423 coupled decays a selection of candidates to the CP violating KL into pi+ pi- decay was performed. CP violating decays were not identified because of the domination of events with a KL regenerating at the Be beam pipe into KS and a background from KL semileptonic decays. The regeneration cross section of 110 MeV/c KL mesons was found to be 53 +- 17 mb in agreement with theoretical expectations. The angular distribution of KS mesons after regeneration and the total cross section of KL for Be have been measured.Comment: 14 pages, 8 figure

Comparing the steric height in the northern Atlantic with satellite altimetry

Anomalies of dynamic height derived from ananalysis of Argo profiling buoys data are analysed to assessthe relative roles of contributions from temperature and salinityover the North Atlantic for the period of 1999–2004. Theyare compared with dynamic topography anomalies based onTOPEX/Poseidon and Jason altimetry. It is shown that thehalosteric contribution to the anomalies of dynamic heightis comparable in magnitude to the thermosteric one overthe period analyzed. Taking both salinity and temperatureinto account improves the agreement between zonally averagedtrends in the satellite dynamic topography and dynamicheight increasing the correlation between them to 0.73 from0.63 when only temperature variability is taken into account.The implication of this result is that the salinity contributioncannot be neglected in the North Atlantic and that one cannotrely on estimating the thermosteric part by anomalies in thesea surface dynamic topography derived from the satellite altimetry