19 research outputs found

    Horizon-T Experiment Detailed Calibration of Cables

    Full text link
    The ability to extract the pulse width and translate it into the actual disk width of the Extensive Air Showers (EAS) is a hard one requiring accurate knowledge of the system performance. For that, the analysis for the cable calibration for Horizon-10T detectors has been re-analyzed in a different form that allows for better signal width measurements. An innovative detector system Horizon-10T, constructed to study EAS in the energy range above 1016 eV coming from a wide range of zenith angles (0o - 85o), is located at Tien Shan high-altitude Science Station of Lebedev Physical Institute of the Russian Academy of Sciences at approximately 3340 meters above the sea level.Comment: in-depth analysis of cable calibration for 'new' cables only v2 corrects minor typo

    Hydroisomerization of n-Hexane Using Acidified Metal-Organic Framework and Platinum Nanoparticles.

    No full text
    Exceptionally high surface area and ordered nanopores of a metal-organic framework (MOF) are exploited to encapsulate and homogeneously disperse a considerable amount of phosphotungstic acid (PTA). When combined with platinum nanoparticles positioned on the external surface of the MOF, the construct shows a high catalytic activity for hydroisomerization of n-hexane, a reaction requiring hydrogenation/dehydrogenation and moderate to strong Brønsted acid sites. Characterization of the catalytic activity and acidic sites as a function of PTA loading demonstrates that both the concentration and strength of acidic sites are highest for the catalyst with the largest amount of PTA. The MOF construct containing 60% PTA by weight produces isoalkanes with 100% selectivity and 9-fold increased mass activity as compared to a more traditional aluminosilicate catalyst, further demonstrating the capacity of the MOF to contain a high concentration of active sites necessary for the isomerization reaction

    Molecular catalysis science: Perspective on unifying the fields of catalysis

    No full text
    Colloidal chemistry is used to control the size, shape, morphology, and composition of metal nanoparticles. Model catalysts as such are applied to catalytic transformations in the three types of catalysts: heterogeneous, homogeneous, and enzymatic. Real-time dynamics of oxidation state, coordination, and bonding of nanoparticle catalysts are put under the microscope using surface techniques such as sum-frequency generation vibrational spectroscopy and ambient pressure X-ray photoelectron spectroscopy under catalytically relevant conditions. It was demonstrated that catalytic behavior and trends are strongly tied to oxidation state, the coordination number and crystallographic orientation of metal sites, and bonding and orientation of surface adsorbates. It was also found that catalytic performance can be tuned by carefully designing and fabricating catalysts from the bottom up. Homogeneous and heterogeneous catalysts, and likely enzymes, behave similarly at the molecular level. Unifying the fields of catalysis is the key to achieving the goal of 100% selectivity in catalysis

    Presentation and processing knowledge stored in multidimensional data thought enhanced base semantic hypergraph

    No full text
    В данной работе рассматриваются вопросы представления и обработки знаний. Главной новизной работы является вложенность знаний, представление знаний посредствомрасширенного базового семантического гиперграфа(РБСГ). Построена математическая модель представления знаний. Описаны технология хранения, обработки знаний.In this work we consider the presentation and processing knowledge. The main novelty of this research is the nesting of knowledge which is presented through enhanced base semantic hypergraph (EBSH). The mathematical model of presentation of knowledge is built. The storage technology and knowledge processing are described. The client side of knowledge presentation is presented

    Unresectable Recurrent Multiple Meningioma: A Case Report with Radiological Response to Somatostatin Analogues

    No full text
    Medical treatment of meningiomas is reserved for cases in which surgery and radiotherapy have failed. Given that a high percentage of meningiomas express somatostatin receptors, treatment with somatostatin analogues has been proposed. In addition, these medications have been shown to have an antiproliferative and antiangiogenic effect in vitro. To date, very few cases with clinical response and none with radiological response have been described. The case described here is the first to report a radiological response. A 76-year-old Caucasian male was first diagnosed with unresectable meningioma at age 47. The patient experienced multiple recurrences and underwent three surgeries and radiotherapy over the years from the initial diagnosis. Despite treatment, the disease continued its progression. Based on an Octreoscan positive for tumour uptake, therapy with extended-release somatostatin analogues was started. Although no clinical neurological improvement was observed, magnetic resonance imaging scans revealed a discreet but continuous radiological response over time. After >2 years of continuous administration of lanreotide, the patient remains progression free. In highly selected cases, somatostatin analogue treatment for meningioma may be beneficial. Based on our findings, treatment with somatostatin analogues should be maintained longer than previously described before evaluating treatment response
    corecore