560 research outputs found
Luminescent coordination polymers based on Ca²⁺ and octahedral cluster anions [{M₆Clⁱ₈}Clᵃ₆}²⁻ (M = Mo, W) : synthesis and thermal stability studies
Luminescent coordination polymers (CPs) based of inexpensive stable precursors are attractive materials for applications. Here we report the synthesis and evaluation of the stability and photophysical characteristics of the first examples of phosphorescent CPs based on octahedral molybdenum and tungsten cluster anions. Specifically 1D CP trans-[{Ca(OPPh₃)₄}{{M₆Clⁱ₈}Clᵃ₆}]∞ (M = Mo, W) can be obtained either directly at increased temperature or via intermediate phases [cis-Ca(OPPh₃)₄(H₂O)₂][{M₆Clⁱ₈}Clᵃ₆]∙2CH₃CN that are stable at room-temperature, but convert to the titled CP at temperatures above 100 °C
Meteoprotective properties of melaxen in old and middle aged patients with ischemic heart disease in combination with arterial hypertension
We studied 102 patients (mean age 60.1±3.3 years) with arterial hypertension (AH) II-III stage, grade 2-3 and ischemic heart disease (exertional angina functional class (FC) I-II, postinfarction cardiosclerosis). The control group of patients received traditional therapy (TT): beta -blockers, calcium channel blockers, ACE inhibitors, antiplatelet agents, diuretics and nitrate
Core acid treatment influence on well reservoir properties in Kazan oil-gas condensate field
The research involves investigation of the influence of hydrochloric acid (HCI-12%) and mud acid ( mixture: HCl - 10 % and HF - 3 %) treatment on the Upper-Jurassic reservoir properties in Kazan oil-gas condensate field wells. The sample collection included three lots of core cylinders from one and the same depth (all in all 42). Two lots of core cylinders were distributed as following: first lot - reservoir properties were determined, and, then thin sections were cut off from cylinder faces; second lot- core cylinders were exposed to hydrochloric acid treatment, then, after flushing the reservoir properties were determined, and thin sections were prepared. Based on the quantitative petrographic rock analysis, involvin 42 thin sections, the following factors were determined: granulometric mineral composition, cement content, intergranular contacts and pore space structure. According to the comparative analysis of initial samples, the following was determined: content decrease of feldspar, clay and mica fragments, mica, clay and carbonate cement; increase of pore spaces while in the investigated samples- on exposure of rocks to acids effective porosity and permeability value range is ambiguous
Empirical evidence for unique hues?
Red, green, blue, yellow, and white have been distinguished from other hues as unique. We present results from two experiments that undermine existing behavioral evidence to separate the unique hues from other colors. In Experiment 1 we used hue scaling, which has often been used to support the existence of unique hues, but has never been attempted with a set of non-unique primaries. Subjects were assigned to one of two experimental conditions. In the "unique" condition, they rated the proportions of red, yellow, blue, and green that they perceived in each of a series of test stimuli. In the "intermediate" condition, they rated the proportions of teal, purple, orange, and lime. We found, surprisingly, that results from the two conditions were largely equivalent. In Experiment 2, we investigated the effect of instruction on subjects' settings of unique hues. We found that altering the color terms given in the instructions to include intermediate hues led to significant shifts in the hue that subjects identified as unique. The results of both experiments question subjects' abilities to identify certain hues as unique
On Local Behavior of Holomorphic Functions Along Complex Submanifolds of C^N
In this paper we establish some general results on local behavior of
holomorphic functions along complex submanifolds of \Co^{N}. As a corollary,
we present multi-dimensional generalizations of an important result of Coman
and Poletsky on Bernstein type inequalities on transcendental curves in
\Co^{2}.Comment: minor changes in the formulation and the proof of Lemma 8.
Detection Statistics of Pulse Signals at Declinations from to at the Frequency 111 MHz
A search for pulse signals was carried out in a new sky area included in the
monitoring program for the search for pulsars and transients. Processing of
several months data recorded in six frequency channels with a total bandwidth
of 2.5 MHz showed that, on average, 4 pulses per hour are observed in each of
the 24 connected stationary beams. Of these pulses, 18.3% are similar to those
of pulsars. They are visible in one or two neighboring beams and have a
pronounced dispersion shift, that is, they are recorded first at a high and
then at a low frequency, which indicates the possible passage of the signal
through the interstellar medium. Almost 68% of such detected pulses belong to
six known pulsars with dispersion measures from 9 to 141 , and almost
all of the remaining pulses are either noise of an unknown nature or artifacts
of the proposed pulse separation technique. An additional study of the selected
array of 3650 obvious pulsar pulses revealed 13 pulses belonging to four
rotating radio transients (RRATs). Their dispersion measures are in the range
of 17-51 . A search for regular (periodic) RRAT emission was carried
out using power spectra summed over 121 days. Periodic radiation was not
detected, but for two RRATs, upper estimates of the periods were obtained from
measurements of the time intervals between pulses. The upper estimates of the
integrated flux density of the detected RRATs are in the range 2-4 mJy at the
frequency 111 MHz.Comment: published in Astronomy Report, translated by Yandex translator with
correction of scientific lexis, 6 pages, 3 figures, 2 table
Detection of two new RRATs at 111 MHz
A search for pulse signals in a area with declinations of +52\degr <\delta
<+55\degr was carried out on the LPA LPI radio telescope. When processing ten
months of observations recorded in six frequency channels with a channel width
of 415 kHz and a total bandwidth of 2.5 MHz, 22 thousand events were found with
a pronounced dispersion delay of signals over frequency channels, i.e. having
signs of pulsar pulses. It turned out that the found pulses belong to four
known pulsars and two new rotating radio transients (RRATs). An additional
pulse search conducted in 32-channel data with a channel width of 78 kHz
revealed 8 pulses for the transient J0249+52 and 7 pulses for the transient
J0744+55. Periodic radiation of transients was not detected. The analysis of
observations shows that the found RRATs are most likely pulsars with nullings,
where the proportion of nulling is greater than 99.9\%.Comment: published in Astronomy Reports, translated by Yandex translator with
correction of scientific lexis, 5 pages, 2 figures, 1 tabl
Multiple fates of newly synthesized neurofilament proteins: evidence for a stationary neurofilament network distributed nonuniformly along axons of retinal ganglion cell neurons.
Pushchino multibeams pulsar search. IV. Detection of new pulsars at declinations -9o < \delta < +55o
The search for pulsars in monitoring data obtained at the radio telescope
Large Phased Array (LPA) at a frequency of 111 MHz was carried out. Daily
round-the-clock observations were carried out for about 3,000 days. The
duration of the observation session for each direction in the sky was 3.5
minutes per day. The search for pulsars was carried out using power spectra. To
search for weak pulsars, power spectra were summed up. The expected increase in
sensitivity was 35-40 times compared to observations in one session. In a blind
search, 330 pulsars with regular radiation were detected, with periods (P) from
0.0333 to 3.7455 s and dispersion measures (DM) up to 249 pc/cm3. 39 pulsars
turned out to be new. Average profiles were obtained for 6 pulsars. The DM for
7 pulsars previously detected on the LPA have been clarified.Comment: published in MNRAS, 13 pages, 4 figures, 4 tables, 4 appendixe
GEMINGA: NEW OBSERVATIONS AT LOW RADIO FREQUENCIES
ABSTRACT. After nearly 10 years, we have succeeded to detect radio emission from Geminga more again. In this report we present new evidence for presence of radio emission from Geminga in the range 42-112 MHz. The observations were carried out on two sensitive transit radio telescopes We used three new digital receivers to detect the pulses and to obtain dynamic spectra.The examples of mean pulse profiles are presented. Exact value of the dispersion measure have been calculated using the simultaneous observations at three frequencies
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