Let Pk denote any integer with no more than k prime factors, counted according to multiplicity. It is proved that for almost all sufficiently large integers n, satisfying n is identical with 0 or 1 (mod 3), the equation n = p1+p2/2 +p2/3 has a solution in primes p1, p2, p3 such that p1+2 = P6, p2+2 = P5, p3+2 = P5. It is also proved that for every suffciently large integer M is identical with 0 or 2 (mod 3), the equation M = p1+p2/2+p2/3+p2/4+p2/5 has a solution in primes p1, ź ź ź , p5 such that p1+2 = P6, p2+2 = P5, p3+2 = P5, p4+2 = P2, p5+2 = P'/2.
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This paper describes the development of a dual plane Electrical Impedance Tomography (EIT) system that is capable of acquiring data at frame rates of around 1000 dual-frames per second (dfps) providing both magnitude and phase information. The principles of the hardware operation are discussed and the operation of the control software is described. Five separate experimental setups ranging from a simple rising bubbles test to a oscillatory baffled reactor and flow velocity profiles demonstrate that fast acquisition rates provide essential information in some type of applications.
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Nanostructured spherical spinel lithium manganate with about 30 nm in diameter was synthesized for the first time by explosive method. The water-solubility explosive was prepared using a simple facility at room temperature. The growth of lithium manganate via detonation reaction was investigated with respect to the presence of an energetic precursor, such as the metallic nitrate and the degree of confinement of the explosive charge. The detonation products were characterized by scanning electron microscopy. Powder X-ray diffraction and transmission electron microscopy were used to characterize the products. Lithium manganate with spherical morphology and more uniform secondary particles, with smaller primary particles of diameters from 10 to 50 nm and a variety of morphologies were found. Lithium manganate with a fine spherical morphology different from that of the normal spinel is formed after detonation wave treatment due to the very high quenching rate. It might also provide a cheap large-scale synthesis method. Explosive detonation is strongly nonequilibrium processes, generating a short duration of high pressure and high temperature. Free metal atoms are first released with the decomposition of explosives, and then theses metal and oxygen atoms are rearranged, coagulated and finally crystallized into lithium manganate during the expansion of detonation process.
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Trace metals in the brain play an important role in the function of central nervous system (CNS). The objective of this work is to investigate the effects of intranasal exposure of nano- and submicron-sized Fe2O23, particles on the homeostasis of trace metals in the brain. After a single intranasal instillation of nano- and submicron-sized Fe2O23, particles, the contents of Fe, Cu and Zn in the sub-brain regions were determined in the time course from 4 h till to the 30 day post-exposure. Our results indicated that the imbalance of trace metals in the sub-brain regions of mice was induced by the two sizes of Fe2O23, particles. The more significant accumulation of Fe in the brain was found in the nano-Fe2O23., treated mice than in the submicron-Fe2O23, treated ones; meanwhile, similar alterations of Zn contents in the brain were observed as well. A strong positive correlation between Fe and Zn levels in the olfactory bulb of nano-Fe2O23 instilled mice and in the hippocampus and cerebral cortex of submicron-Fe2O23 instilled mice were found. This is the first trial to investigate the disturbance of trace metals in the brain after exposure to Fe2O23 nanoparticles. These results state that much attention should be paid to the potential impact of inhaled FCjCX, nanoparticles on the CNS.
PL
Metale śladowe odgrywająistotnąrolę w funkcjonowaniu ośrodkowego układu nerwowego. Celem tej pracy jest zbadanie wpływu donosowej ekspozycji nano- i submikronowej wielkości cząstek Fe2O23 na homeostazę mikroelementów w mózgu. Badano zawartość Fe, Cu i Zn w czasie od 4 godzin do 30 dni po donosowym podaniu cząstek Fe2O23, o rozmiarach ťano- i submikronowych. Uzyskane rezultaty wskazują, że te dwa rozmiary cząstek Fe2O23., wywoływały zaburzenia równowagi powyższych mikroelementów w różnych strukturach mózgu myszy. W mózgu myszy potraktowanych nano-Fe2O3 zaobserwowano znaczniejszą akumulację Fe niż u myszy potraktowanych submikrono-Fe2O Podobne zmiany zaobserwowano również w zawartości Zn w mózgu. Zaobserwowano istotną korelację między zawartością Fe i Zn w opuszce węchowej myszy, którym podano nano-Fe2O oraz w hipokampie i korze mózgowej myszy potraktowanych submikrono-Fe2O praca ta stanowi pierwszą próbę zbadania zaburzenia poziomu metalicznych mikroelementów w mózgu po ekspozycji nanocząsteczkami Fe2O Uzyskane dane wskazują, że należy zwracać szczególną uwagę na potencjalny wpływ wdychanych nanoczastek Fe2O na ośrodkowy układ nerwowy.
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