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    Isotopic and isotonic yields in nuclear fission
    (T.A.E.C. Çekmece Nuclear Research Center, 1962) Erben, M. Talat; Güven, Binay; TAEK-ÇNAEM
    The curves for isotopic and isotonic fission yields are calculated and shown to be the Weierstrass transforms of the isoboaric yield curve. The Well-known mass asymmetry of the fission is associated with asymmetry in charge and in neutron contents. There are "forbidden" zones at 44 Z 48 and at 64 N 78, where formation probabilities are extremely low. The distribution of the number of neutrons of the fission fragments is much narrower than what would be expected on the basis of the variation ranges for Z and N. The ambiguity existing about whether the fragments of a pair are meant to complement before or after prompt neutron boil-off is removed, and Glendenin's treatment is confirmed. There are indications, which are in full agreement with the properties of Wahl's empirical Z(p) function, that the proton closed shell contribution (if any) to the fine structure observed in the isobaric yield curve may be larger than the contribution of the neutron closed shell. The isotopic yields of the known nuclides are significantly smaller than the yields defined by the full theoretical curves for Z = 38, 39, 40, 41, 52, and 57, indicating that new isotopes of Sr, Y, Zr, Nb, Te, and La are still to be identified as primary fission products from the thermal neutron fission of U(235).
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    The most general equations for multigroup neutron diffusion in P1 approximation
    (T.A.E.C. Çekmece Nuclear Research Center, 1962) Şuhubi, Erdoğan; Özemre, Ahmed Yüksel; TAEK-ÇNAEM
    Starting from the general transport equation and within the limits of P1 approximation, a set of coupled second order partial integro-differential equations is obtained. These equations consider the effect of m groups of retarded neutrons and contain both the first and the second derivatives of the neutron fluxes with respect to the time variable.
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    On second order correction to the average extrapolation length
    (T.A.E.C., Çekmece Nuclear Research Center, 1963) İnönü, E.; TAEK-ÇNAEM
    A first-order expression for the average extrapolation length in bare thermal reactors was given previously on the basis, of a many-group calculation. C. Yalçın extended this calculation to second order and obtained a complicated correction term which does not seem easy to apply. His results are analyzed and simplified here by considering the limit for continuous slowing down. It is shown that the second order correction is of the order of d/R, where is the first order average extrapolation length and R is a length which characterizes the size of the reactor.
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    Derivation de I'equation de nordheim a partır de I'equation de diffusion
    (T.A.E.C. Çekmece Nuclear Research Center, 1963) Özemre, Ahmet Yüksel; TAEK-ÇNAEM
    Bu makalede Nordheim denklemi, sâdece çoğaltkan bir ortamın ılık nötronlarının difüzyon denklemine dayanılarak çıkartılmaktadır. Bu, farklı m grup gecikmiş nötronun ortamın nötron bilançosuna iştiraklerini uygun bir tarzda ifâde eden bir kaynak teriminin difüzyon denklemine ilâvesiyle gerçekleştirilmiştir. Nordheim denklemini elde etmek için tek bir diferansiyel denklemin göz önüne alınmış olması, şimdiye kadar tatbik edilmekte olan ve ılık nötronların difüzyon denkleminden ve aynı zamanda gecikmiş nötron neşreden fisyon ürünü ana çekirdeklerin yoğunluklarını veren m adet küple denklemden faydalanma esâsına dayanan metoda nisbetle âşikâr olarak mühim bir sâdelik arzetmektedir.
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    Crystal spectrometer measurement of Çekmece TR-1 thermal neutron spectrum
    (T.A.E.C., Çekmece Nuclear Research Center, 1964) Domaniç, F.; TAEK-ÇNAEM; Akyüz, Ö.; Bayvas, F.; Cansoy, Ç.
    The Thermal Neutron Spectrum of Çekmece TR-1 was measured by using a double drystal spectrometer and NaCf crystal with its (200) plane as monochromator. The neutron energy which corresponds to the maximum of thermal flux distribution was found to be E(0) = 0,0595 ev. Assuming that the flux distribution to be Maxwellian an attempt was made to analyze the measured data to evaluate the effective neutron temperature in the beam hole. Because the theoretical expressions given in the latest publications are found to be unsatisfactory in representing neutron reflectivity for slow neutrons, an experiment was carried out to determine the reflectivity in dependence of neutron energy, the results of the experiment showed that the reflectivity in proportional to E-0,45. By using this empirical relation the effective neutron temperature was found to be ≈ 337°K.
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    On the Özemre's approach to the problem of reflected media
    (T.A.E.C., Çekmece Nuclear Research Center, 1964-12) TAEK-ÇNAEM; Ertek, Çetin
    It is shown that the global method proposed by Özemre for reflected media is based on a tacit assumption which can not hold in general but which turns out to be a fair approximation. The comparison of this method with the two group and the modified one group theories suggests that it occupies a place between them.
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    On the two dimensional solutions for an elastic semi-infinite medium with couple stress
    (T.A.E.C., Çekmece Nuclear Research Center, 1965-04) Şuhubi, E. S.; TAEK-ÇNAEM
    The governing differential equations for an elastic medium with couple stress are solved for a semi-infinite region in static plane deformation by using Fourier transforms. The formal solution can be utilized in a large class of boundary value problems concerning the region in question. For an arbitrary distribution of surface tractions and moments explicit results are given and the solution is obtained for the uniformly distributed surface tractions and moments.
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    Kinetics of the reaction of Tetrachloro-p-Benzoquinone with TRI-n-Dodecyl amine
    (T.A.E.C. Çekmece Nuclear Research Center, 1965-10) Erben, M. Talat; Dinçler, Güngör; TAEK-ÇNAEM
    The kinetics of the reaction of chloranil with tri-n-dodecyl amine have been investigated in the temperature range 100-115.5°C and in the concentration range 0.036-0.0697 M. The kinetics follow a simple second-order mechanism. The energy of activation is 19.7 Kcal./mole. The reaction product is a quaternary amnonium salt, (trichloro-p-benzoquinonyl)-tri-n-dodecyl ammonium chloride. The rate constant is given by: k = 5.74 x 10(10) exp(-9950/T) (minute)(-1) (mole)(-1)
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    Inversion of the cyanide group into iso-cyanide under gamma irradiation
    (T.A.E.C., Çekmece Nuclear Research Center, 1965-10) Erben, M. Talat; Ünseren, Envare; Seber, Nurten; TAEK-ÇNAEM
    Infrared spectrophotometric evidence indicates that gamma irradiation of the nitriles causes partial inversion of the cyanide group into iso-cyanide according to the following mechanism: In the gamma flux, some of the cyanide groups are detached from the nitrile as cyan free radicals and, owing to their resonance-hybrid structure, .C=N - <-> - C=N., two distinct recombination processes take place leading partly to the usual cyanide and partly to the iso-cyanide, respectively. From a comparison of the optical densities at the characteristic frequency of the iso-cyanide absorption band in irradiated methacrylonitrile and ethyl iso-cyanide it is concluded that at least 20% of the cyanide groups were transformed into iso-cyanide in a specific sample of methacrylonitrile irradiated to a total dose of 0.1 megarads.
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    A home-made neutron crystal spectrometer for research and training
    (T.A.E.C., Çekmece Nuclear Research Center, 1965-11) Akyüz, R. Ö.; Cansoy, Ç.; Domaniç, F.; TAEK-ÇNAEM
    In order to make experimental research in the field of low energy nuclear physics, a crystal neutron spectrometer is constructed in ÇNAEM. The energy range is between 0,025 - 6 eV. The available monochromator single crystals are Be, NaCl, (CaCO3), Pb. The minimum precise rotation of spectrometer is 1 minute of arc in Bragg angle. Two Soller type collimators, one from reactor to crystal and the other from sample to counter, are used. The net angular divergence is approximately 5 minutes of arc. Counting system consists of two channels, one of which is used for monitoring the reactor. Counter tubes are B10 enriched BF3 proportional counters. The main problem in construction was, to design and give precise movement to the heavy crystal shielding.
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    Topkapı Sarayı harem dairesi su yollarının sodyum-24 kullanılarak izlenmesi
    (T.C. Başbakanlık Atom Enerjisi Komisyonu, Çekmece Nükleer Araştırma Merkezi, 1965-3) Edgüer, E.; Göksel, S. A.; Öner, Ö.; Soyberk, Ö.; Tömek, F.; TAEK-ÇNAEM
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    Turkish Atomic Energy Commission third activity report of the radioactive fallout laboratory : for the period of August 1965 - July 1966
    (Turkish Atomic Energy Commission, 1966) Şenvar, C. B.; Ergin, M.; Usul, F.; Tuğsavul, Ayşen; Yazgan, E.; Saygılı, N.; TAEK
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    Nükleer güç maliyetinde eğilimler : Atomic Energy of Canada limited raporu no. 2534, 1966
    (T.A.E.K., Çekmece Nükleer Araştırma Merkezi, 1966-06) Haywood, L. R.; TAEK-ÇNAEM; Ünal, Çetin
    Kanada, Fransa, İngiltere ve Birleşik Amerika Devletlerindeki nükleer santralların yayınlanmış hakiki ve tahmin edilen birim yatırım maliyetleri, 1966 yılındaki rayiç dolara ve bir tek 500 MWe’lik üniteyi haiz santrallardaki maliyetlere göre normalize edilmiştir. Böylece maliyet değerlerinin eğilimlerini, birim büyüklüğünün ve fiat artışlarının tesirleri olmaksızın bulmak kabildir. Yayınlanmış santral verimleriyle, birim yatırım maliyetindeki değişmeyi verimdeki değişmeye bağlayan bir katsayı, birim yatırım maliyeti üzerinde, verimi arttırmanın tesirini hesaplamayı mümkün kılar. Candu Nükleer Santrallarından elde edilecek enerjinin maliyetini indirecek pek çok faktör teklif edilmiş ve bu faktörlerin herbirinin bu indirimdeki payı bir özel hal için hesap edilmiştir. Teklif edilmiş faktörler ve ünitenin 1976 yılında işletmeye açılacağı farzedilerek, 1000 MWe lik Candu ünitesinden elde edilecek enerjinin maliyeti bulunmuştur.
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    Determination of thallium by activation analysis based on the reaction 203T1 (n, 2n) 202T1
    (T. A. E. C., Çekmece Nuclear Research Center, 1966-09) Erben, M. Talat; Okar, Sevim; TAEK-ÇNAEM
    Thermal neutron activation of thallium leads to 3.9-year 204T1 and 4.3-min. 206T1 isotopes which are not gamma emitters. However, a method of analysis based on the reaction 203T1(n, γ) 204T1 has been developed by Delbecq et al., and used to detect thallium amounts with a sensistivity of 0.1 µg. In spite of this high sensitivity, this method has the disadvantage of measuring the beta activity and therefore is not very specific. In the present note an activation analysis based on the reaction 203T1(n,2n) 202T1 is discussed. The product isotope 202T1 has a convenient half-life of 12 days and is a gamma emitter, thereby makes the determination specific. On the other hand, owing to the rather high threshold (8-9 MeV) for this reaction the sensitivity is only about 20 µg of thallium for samples irradiated for 30 hours in the close-vicinity of the reactor fuel in a total flux of 10(13) n/cm2/sec.
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    Memleketimizde nükleer gücün maliyeti
    (T.A.E.K. Çekmece Nükleer Araştırma Merkezi, 1966-10) Ünal, Çetin; TAEK-ÇNAEM
    Memleketimizde 1975 yalında kurulacağı kabul edilen nükleer güç santrailarından elde edilecek birim enerji maliyetleri, 3 tip nükleer güç santralı, yani kaynayan su reaktörü, gaz ile soğutulan ve grafit ile yavaşlandırılan reaktör ve ağır su ile yavaşlardırilan ve soğutulan reaktör kullanan 300 MWe, 4-00 MWe, 500 MWe, 700 MV/e kapasitelerindeki nükleer güç santrali arı için yük faktörleri 0,8 ve 0,5 alınarak hesap edildi, Böylece nükleer güç santrallarının esas yükü ve pik yükü taşı» ması fonksiyonları halinde birim enerji maliyetlerinin mukayesesi yapılabilir. Elde edilmiş birim enerji maliyetleri, Türkiye'deki şimdiki ortalama birim enerji maliyetinden daha düşüktür. Bu çalışmada varılan netice, Türkiye'de mümkün olan en yakın gelecekte, nükleer güç santrallarının kurulması lâzım geldiği hususudur. Hemekadar, bir nükleer güç santralı kurulmasında ekonomik kriter, birim enerji maliyetinin ucuzluğu ise de, bu kriterden ağır basan diğer kriterler, en ekonomik tipin seçilmemesini de mümkün kılabilir.
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    Syntheses based on cholanic acid, ∆ 23 - cholone and 23 - amino norcholane
    (T.A.E.C. Çekmece Nuclear Research Center, 1967-04) Ünseren, Envare; TAEK-ÇNAEM
    Reduction of cholanic acid (III) with lithium aluminum hydride gave cholanyl alconol (IV). Benzoate, chloride, pyridinium chloride hydrate, ethyl carbonate, S-metnyl xanthate derivatives of cholanyl alcohol have been prepared, ∆23-Cholene has been obtained by the pyrolysis of the last two products. Osmium tetroxide hydroxylation of ∆-cnolene afforded 23,24-dioxy cholane (VIII). Schmid reaction on cholanic acid gave 23-amino norcholane (IX). Acetyl, benzoyl, and tosyl derivatives of the amine have been prepared. Reaction with potassium isocyanate gave norcholanyl urea (IX e). Norcholanic acid (X) has been obtained by the alcaline permanganate oxidation of 23-amino norcholane. Lithium aluminum hydride reduction of norcholanic acid gave norcholanyl alconol (XI).
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    Pozitif ilimlerde, izotop tatbikatının resimlerle izahı
    (T.C. Atom Enerjisi Komisyonu, 1968) TAEK; Yülek, G. Gürcan
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    Nükleer yakıt ekonomisi konulu simpozyum hakıında rapor
    (T.C. Atom Enerjisi Komisyonu, 1968) TAEK; Aybers, Nejat