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131.
A. P. Sorokin A. D. Efanov E. F. Ivanov D. E. Martsinyuk G. P. Bogoslovskaya K. S. Rymkevich V. L. Mal’kov 《Atomic Energy》1999,87(5):801-807
The physics of the processes, the characteristics, and the stability of different regimes, of boiling (nucleate, projectile,
disperse-ring), which are observed in experiments investigating the boiling of liquid-metal coolant in a model of a fuel assembly
for a fast-neutron reactor in the emergency cooldown regime with low circulation velocity, are analyzed. The experimental
setup, the, methods for performing measurements, and the experimental data on the boiling of a liquid metal are described.
A mathematical model of the process of boiling of a liquid-metal, coolant in a natural-circulation loop is described, and
the results of test calculations for regimes with an increase in heating and with sharp pressure drop are prresented. 7 figures,
12 references.
State Science Center of the Russian Federration–A. I. Leipunskii Physics and Power Engineering Institute. Translated from
Atomnaya énergiya, Vol. 87, No. 5, pp. 337–342, November, 1999. 相似文献
132.
133.
Robert Czarnomysy Anna Muszyska Jakub Rok Zuzanna Rzepka Krzysztof Bielawski 《International journal of molecular sciences》2021,22(11)
Transition metal coordination compounds play an important role in the treatment of neoplastic diseases. However, due to their low selectivity and bioavailability, as well as the frequently occurring phenomenon of drug resistance, new chemical compounds that could overcome these phenomena are still being sought. The solution seems to be the synthesis of new metal complexes conjugated with drug carriers, e.g., dendrimers. Numerous literature data have shown that dendrimers improve the bioavailability of the obtained metal complexes, solving the problem of their poor solubility and stability in an aqueous environment and also breaking down inborn and acquired drug resistance. Therefore, the aim of this study was to synthesize a novel imidazole platinum(II) complex conjugated with and without the second-generation PAMAM dendrimer (PtMet2–PAMAM and PtMet2, respectively) and to evaluate its antitumor activity. Cell viability studies indicated that PtMet2–PAMAM exhibited higher cytotoxic activity than PtMet2 in MCF-7 and MDA-MB-231 breast cancer cells at relatively low concentrations. Moreover, our results indicated that PtMet2–PAMAM exerted antiproliferative effects in a zebrafish embryo model. Treatment with PtMet2–PAMAM substantially increased apoptosis in a dose-dependent manner via caspase-9 (intrinsic pathway) and caspase-8 (extrinsic pathway) activation along with pro-apoptotic protein expression modulation. Additionally, we showed that apoptosis can be induced by activating POX, which induces ROS production. Furthermore, our results also clearly showed that the tested compounds trigger autophagy through p38 pathway activation and increase Beclin-1, LC3, AMPK, and mTOR inhibition. The high pro-apoptotic activity and the ability to activate autophagy by the imidazole platinum(II) complex conjugated with a dendrimer may be due to its demonstrated ability to reverse multidrug resistance (MDR) and thereby increase cellular accumulation in breast cancer cells. 相似文献
134.
O. A. Bannykh S. V. Grachev L. A. Mal’tseva V. M. Blinov M. V. Kostina N. N. Ozerets 《Metal Science and Heat Treatment》2006,48(1-2):9-12
Direct and reverse elastic aftereffects in corrosion-resistant nitrogen-bearing steel Kh21G10N7MBF (0.5% N) are considered
depending on the preliminary heat treatment (quenching + deformation + aging) and on the temperature and time conditions of
the occurrence of the direct and reverse elastic aftereffects.
__________
Translated from Metallovedenie i Termicheskaya Obrabotka Metallov, No. 1, pp. 8–11, January, 2006. 相似文献
135.
136.
Zbyšek Pavlík Lukáš Fiala Miloš Jerman Eva Vejmelková Milena Pavlíková Martin Keppert Robert Černý 《International Journal of Thermophysics》2014,35(9-10):1912-1921
The moisture-dependent thermal conductivity of two types of lightweight ceramic brick body is analyzed using both theoretical and experimental approaches. The basic physical properties are determined at first. Then, an impulse method is applied for the thermal-conductivity measurement. Initially, the material samples are dried, after that, they are exposed to liquid water for specific time intervals, and finally the moisture content is allowed to homogenize within the whole volume. The thermal-conductivity measurement is performed for different moisture contents achieved in this way. In the theoretical part, the homogenization principles are used for the calculation of the moisture-dependent thermal conductivity, utilizing the distribution functions based on the pore-size distribution measurement. Finally, a comparison of the measured and calculated data is done, and the validity of the applied effective media treatment is assessed. 相似文献
137.
Natália Tomašovičová Milan Timko Vlasta Závišová Anežka Hashim Jan Jadzyn Xavier Chaud Eric Beaugnon Peter Kopčanský 《International Journal of Thermophysics》2014,35(11):2044-2053
We have studied the influence of electric and magnetic fields on the orientational structure of ferronematics based on a thermotropic nematic 4-trans-4 \(^{\prime }\) -n-hexylcyclohexyl-isothiocyanato-benzene (6CHBT). The 6CHBT liquid crystal has been dissolved in phenyl isothiocyanate and doped with rod-like or chain-like magnetic particles. In such a mixture, the phase transition from an isotropic to a nematic phase is via a droplet state, i.e., coexistence of nematic and isotropic phases. The obtained results showed that a combination of the electric and magnetic fields can change the character of a phase transition from the isotropic to the nematic phase via the droplet state in such systems. Moreover, magneto-dielectric measurements of structural transitions showed the magnetic field induced a shift of the phase transition temperature from the isotropic to the droplet state. 相似文献
138.
Pierre Rossi Jean Philippe Charron Maléna Bastien-Masse Jean-Louis Tailhan Fabrice Le Maou Sandrine Ramanich 《Materials and Structures》2014,47(10):1773-1785
The paper presents experimental results concerning the comparison of tensile and compressive basic creep behaviours at early ages of two different concretes: a normal strength concrete (NSC) and a very high strength fibre reinforced concrete (HPFRC). This research project has been done in the context of a bilateral collaboration between Polytechnique Montreal and IFSTTAR. Observations on the HPFRC showed specific compressive creep similar to the specific tensile creep. Moreover, the specific creep curves obtained under compressive and tensile loading had always positive values, i.e. they were in same direction of the applied load on specimens. Measurements made on the NSC revealed specific compressive creep with positive values (in the loading direction). However, specific tensile creep presented negative values (opposite direction of loading) for a long period. A physical explanation based on the existence of two mechanisms with opposite effect is proposed to describe these basic creep results. The first mechanism is a coupling between the microcracking process and the water transfers that lead to additional self-drying shrinkage; the second mechanism is the self-healing of concrete induced by the microcracking. 相似文献
139.
Alexander Pyattaev Jiri Hosek Kerstin Johnsson Radko Krkos Mikhail Gerasimenko Pavel Masek Aleksandr Ometov Sergey Andreev Jakub Sedy Vit Novotny Yevgeni Koucheryavy 《ETRI Journal》2015,37(5):877-887
This paper is a first‐hand summary on our comprehensive live trial of cellular‐assisted device‐to‐device (D2D) communications currently being ratified by the standards community for next‐generation mobile broadband networks. In our test implementation, we employ a full‐featured 3GPP LTE network deployment and augment it with all necessary support to provide real‐time D2D connectivity over emerging Wi‐Fi‐Direct (WFD) technology. As a result, our LTE‐assisted WFD D2D system enjoys the required flexibility while meeting the existing standards in every feasible detail. Further, this paper provides an account on the extensive measurement campaign conducted with our implementation. The resulting real‐world measurements from this campaign quantify the numerical effects of D2D functionality on the resultant system performance. Consequently, they shed light on the general applicability of LTE‐assisted WFD solutions and associated operational ranges. 相似文献
140.
Individual monitoring of aircrew of airline operators registered in the Czech Republic has been performed since 1998. In this work, annual effective doses and annual collective effective doses of aircrew from occupational exposure in the period from 1998 to 2008 are presented, methods used for their evaluation and verification are described, and general trends observed in the data are discussed. Annual effective doses were calculated using the computer code CARI from flight schedules provided by airline operators and typical flight profiles. The method was verified via a comparison with (i) measurements using different types of detectors and (ii) calculations using the CARI and EPCARD codes with actual flight data. It was found that average annual effective doses in the period from 1998 to 2008 were in the range from 1.2 to 2.0 mSv and followed the trend of the solar cycle. Annual collective effective doses increased from 1.4 manSv in 1998 to 4.1 manSv in 2008 as the number of aircrew increased from 857 to 2158 during this period. Combined relative uncertainties (coverage factor ) of reported individual and collective effective doses were ~ 25 %, which is well within the range given by the factor of 1.5. More work is needed to achieve a higher accuracy of this estimate. 相似文献