798 research outputs found
Fluctuation in density of ciliates in Bukan dam reservoir, Zarrinehrud, Iran
The abundance and species composition of ciliates were analyzed in the Bukan Dam Reservoir (West Azerbaijan, Iran) from January to December 2008. Surface water samples were collected at monthly intervals from the middle (Stations 1 and 3) and shallow (Stations 2 and 4) areas of the lake. Three samples were taken in the water column using a 5-litre sampler. Totally 30 liters water was collected, 200 ml of which was fixed immediately with 8.6 ml of a saturated HgCl2 solution and stained with 0.04% bromophenol blue. Three subsamples were counted in a 5-ml chamber and examined with a microscope (100 x) as well as Chlorophyll a and a few ecological parameters such as dissolved oxygen, pH, transperancy and water temperature were measured. Totally 50 ciliates species were found in Bukan Dam Reservoir. Regarding the density, a high-density period was detected from January to April with a mean density of 2.86 x 103 cells.l-1 Ciliata at stations 1 and 3 and 4.16 x 103 cells.l-1 at stations 2 and 4. The high density of ciliate in summer may be due to the increase in the density of bacteria and moderate metazooplankton as a result of the appearance of non-edible algae . The ciliata occurring at the highest densities were Coleps tessellates, Didinium nasutum, Paradileptus elephantinus, Stentor polymorphus, Zosterograptus labiatus, Paramecium bursaria, Cyclidium citrullus, Vorticella campanula, Halteria grandinella and Aspidisca costata. The maximum and minimum chlorophyll a values observed at the reservoir water were 10.39 ”g.l-l and 1.0 ”g.l-l being obtained in May and Octobor respectively
New generation wave technology of residual oil-stock liquid-phase oxidation process intensification
In recent years the attitude to bituminous production in Russia significantly changed. In particular, scientific and practical need for naphtha sorting especially for bituminous production is proved. It was promoted by BASHNIYA NP technological classifications of naphtha from the point of view of their suitability for road asphalts production according to which highparaffinic resinous and paraffinic low-resinous naphtha are recognized unsuitable for production of improved brands road asphalts on the existing technological schemes. Heavy asphaltic naphtha is considered to be the most suitable. The problem of the Heavy Petroleum Residue (HPR) maximal involvement in processing is very timely under conditions of oil products amplifying competition in the market on one hand, and against the increasing requirements to their quality from the point of environment protection view - on the other. Development of scientifically applied bases and the bitumen production technology, applied to road construction, should be noted. Especially it is timely in connection with the bituminous production problems which recently became aggravated sharply in Russia. Timely task for oil refineries (oil refinery) currently is ever growing involvement of high-paraffinic resinous naphtha, with application of raw materials preliminary activation express methods (acoustic exaltation, rotor hydrodynamic source of mechanical oscillations, wave influence) in production of receiving oil oxidated asphalts of improved quality
Early experience with the ARTISENTIALÂź articulated instruments in laparoscopic low anterior resection with TME
Background: The notion of articulation in surgery has been largely synonymous with robotics. The ARTISENTIALÂź instruments aim at bringing advanced articulation to laparoscopy to overcome challenges in narrow anatomical spaces. In this paper, we present first single-center results of a series of low anterior resections, performed with ARTISENTIALÂź. Methods: Between September 2020 and August 2021, at the Department of Surgery, St. Marienkrankenhaus Siegen, Siegen, Germany, patients with cancer of the mid- and low rectum were prospectively enrolled in a pilot feasibility study to evaluate the ARTISENTIALÂź articulated instruments in performing a laparoscopic low anterior resection. Perioperative and short-term postoperative data were analyzed. Results: Seventeen patients (10 males/7 females) were enrolled in this study. The patients had a median age of 66Â years (range 47â80Â years) and a median body mass index of 28Â kg/m2 (range 23â33Â kg/m2). The median time to rectal transection was 155Â min (range 118â280Â min) and the median total operative time was 276Â min (range 192â458Â min). The median estimated blood loss was 30Â ml (range 5â70Â ml) and there were no conversions to laparotomy. The median number of harvested lymph nodes was 15 (range 12â28). Total mesorectal excision (TME) quality was âgoodâ in all patients with no cases of circumferential resection margin involvement (R0 = 100%). The median length of stay was 9Â days (range 7â14Â days). There were no anastomotic leaks and the overall complication rate was 17.6%. There was one unrelated readmission with no mortality. Conclusions: Low anterior resection with ARTISENTIALÂź is feasible and safe. All patients had a successful TME procedure with a good oncological outcome. We will now seek to evaluate the benefits of ARTISENTIALÂź in comparison with standard laparoscopic instruments through a larger study
Extractive Dearomatization of Naphthalane Oil Fraction with Ionic Liquid and -N-Methyl-2-Pyrrolidone
In the article are given an analysis of the results of researches carried out for the purpose of selective treatment of the Naphthalane oil fraction boiling at 260-3400C with ionic liquid (IL) -morfolinphormiate synthesized on the basis formic acid + morpholine and - N-methyl-2-pyrrolidon (N-MP) andĂÂ as an extractant. The aim is to remove poisonous components -ĂÂ sulfur compounds and toxic carcinogenic polynuclear aromatic hydrocarbons in order to improve therapeutic properties of Naphthalane oil cut. For this purpose we have used extraction method. On the basis of the conducted researches the role of -N-methyl-2-pyrrolidone and IL-morpholinephormiatee in extraction conditions have been determined in selective treatment of Nafthalan oil, according to the results of spectral analysis residual amount of aromatic hydrocarbons decreased from 18.5% wt accordance to 2%, 1.5%. As well as the amount of sulphur decreased from 0.0354% to 0.010%,ĂÂ 0.011% and 0.019%.In the next stage the treated raffinates with N-methyl-2-pyrrolidone has been purified on silica. In a result amount of aromatic hydrocarbons drastically decrease to be 0.07% and 0.02%. As a result we aquire transparency and at the same time the percentage amount of aromatic hydrocarbons drastically decreased from 2% to 0,07%, 1.5%, to 0.02%. Raffinates obtained in a 2-4 stage dearomatization with N-MP and IL. Raffinate are measured on NMR, UV and IR spectral analysis
Electron-phonon renormalization of the absorption edge of the cuprous halides
Compared to most tetrahedral semiconductors, the temperature dependence of
the absorption edges of the cuprous halides (CuCl, CuBr, CuI) is very small.
CuCl and CuBr show a small increase of the gap with increasing
temperature, with a change in the slope of vs. at around 150 K: above
this temperature, the variation of with becomes even smaller. This
unusual behavior has been clarified for CuCl by measurements of the low
temperature gap vs. the isotopic masses of both constituents, yielding an
anomalous negative shift with increasing copper mass. Here we report the
isotope effects of Cu and Br on the gap of CuBr, and that of Cu on the gap of
CuI. The measured isotope effects allow us to understand the corresponding
temperature dependences, which we also report, to our knowledge for the first
time, in the case of CuI. These results enable us to develop a more
quantitative understanding of the phenomena mentioned for the three halides,
and to interpret other anomalies reported for the temperature dependence of the
absorption gap in copper and silver chalcogenides; similarities to the behavior
observed for the copper chalcopyrites are also pointed out.Comment: 14 pages, 5 figures, submitted to Phys. Rev.
Static quantities of the W boson in the SU_L(3) X U_X(1) model with right-handed neutrinos
The static electromagnetic properties of the boson, and
, are calculated in the SU_L(3)} \times U_X(1) model with
right-handed neutrinos. The new contributions from this model arise from the
gauge and scalar sectors. In the gauge sector there is a new contribution from
a complex neutral gauge boson and a singly-charged gauge boson .
The mass of these gauge bosons, called bileptons, is expected to be in the
range of a few hundreds of GeV according to the current bounds from
experimental data. If the bilepton masses are of the order of 200 GeV, the size
of their contribution is similar to that obtained in other weakly coupled
theories. However the contributions to both and are
negligible for very heavy or degenerate bileptons. As for the scalar sector, an
scenario is examined in which the contribution to the form factors is
identical to that of a two-Higgs-doublet model. It is found that this sector
would not give large corrections to and .Comment: New material included. Final version to apppear in Physical Review
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Data Archived for Events in the Caucasus for the CauSINCollaboration Project
The Causin project is a joint effort between the countries in the Caucasus region to develop a Probabilistic Seismic Hazard Analysis. To that end, we have compiled a database of all available network data in the region. The information contained in the database is from four countries: Armenia, Georgia, Azerbaijan, and Turkey and from the Incorporated Research Institutions for Seismology (IRIS). Table 1 lists the networks from which data were obtained. Figure 1 shows the locations of stations, and Figure 2 shows ray paths for event locations of the archived data. An ongoing effort in the region is the Caucasus Seismic Information Network (CauSIN) is an international scientific project enabling the countries and scientists of the region to: better understand the seismicity of the greater Caucasus; develop new monitoring networks to support the scientific understanding; provide access to seismic data from local networks in the participating countries; and develop a probabilistic seismic hazards assessment for the region enabling the governments in the region to better mitigate the damaging effects from large earthquakes. In parallel with this effort, training has been conducted on modern techniques for probabilistic hazards assessment. CauSIN is also an ongoing effort to promote cooperation in the geosciences between Georgia, Armenia, Azerbaijan, European Union and the United States. The DOE supports the American team from New England Research, Inc. (NER), Massachusetts Institute of Technology (MIT), Boston College, and Lawrence Livermore National Laboratory (LLNL)
Study of Operating Characteristics of Pyrotechnic Reserve Power Source Based on Magnesium and ZinŃ
This paper presents the results of studies of operating parameters of pyrotechnic reserve power source (PRPS). This battery was activated by the pyrotechnic compositions contained in the electrodes. Once the ignition impulse worked, the pyrotechnic compositions took fire immediately and melted the electrolyte. Then the rest pyrotechnic compositions served as anode and cathode. The battery began to discharge. The following characteristics of PRPS were evaluated during the study: release time to operating regime of the electric current, the duration of the PRPS work and initiation temperature of PRPS. A detailed evaluation of the Mg/LiF/PbF2 electrochemical system and Zn/LiF/PbF2 one is undertaken. Test results show that the electric current value using powder of zinc and granular zinc in these experiments was 0.179 A and 0.1 A, respectively, and the operating time at these values of elecrtic current was 40 and 151 sec, respectively
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