Authors:Mahdi Sadeghi, Nadia Zandi, and Hossein Afarideh
In recent years, there has been a rapid expansion in the use of radio nuclides for therapeutic purposes. Thulium–167 is an
important radionuclide (T1/2 = 9.25 d) due to it could be used for tumor and bone studies in nuclear medicine. 167Tm complexed with hydroxy ethylene diamine tetra-acetic acid (HEDTA) could be used with the aim of bone imaging. 167Tm emits a prominent γ ray of 208 keV energy and low energy electrons. This study describes calculations on the excitation
functions of 165Ho(α,2n)167Tm, 167Er(p,n)167Tm, natEr(d,xn)167Tm and natEr(p,xn)167Tm reactions by ALICE/ASH (hybrid and GDH models) and TALYS-1.0 codes. In addition, calculated data by codes were compared
to experimental data that earlier were published and TENDL-2010 database. Moreover, optimal thickness of the targets and physical
yield were obtained by SRIM (stopping and range of ions in matter) code for each reaction. According to the results, the 167Er(p,n)167Tm and 165Ho(α,2n)167Tm reactions are suggested as the best method to produce 167Tm owing to minimum impurities. The TALYS-1.0 code, predict the maximum cross-section of about 382 mb at 11 MeV and 849 mb
at 26 MeV for 167Er(p,n)167Tm and 165Ho(α,2n)167Tm reactions, respectively. Finally, deposition of natEr2O3 on Cu substrate was carried out via the sedimentation method. The 516 mg of erbium(III)oxide with 103.2 mg of ethyl cellulose
and 8 mL of acetone were used to prepare a natEr2O3 layer of 11.69 cm2. 167Tm was produced via the natEr(p,n)167Tm nuclear process at 20 μA current and 15 → 7 MeV protons beam (1 h). Yield of about 3.2 MBq 167Tm per μA h were experimentally obtained.
Authors:Zoltán Németh, Bernadett Baja, Krisztián Radó, Emese Deák, Kálmán Varga, Andrea Nagy, János Schunk, and Gábor Patek
Decontamination technologies are generally developed to reduce the collective dose of the maintenance and operation personnel
at nuclear power plants (NPP). The highest efficiency (i.e., the highest decontamination factors) available without detrimental
modification of the treated surface of structural material is the most important goal in the course of the application of
a decontamination technology. At the Paks NPP the AP-CITROX procedure has been utilized for the decontamination of the primary
coolant circuit’s components (e.g., main circulating pump (MCP) and steam generators (SGs)). Our previous studies have revealed
that a ‘hybrid’ structure of the amorphous and crystalline phases was formed in the outermost surface region of the austenitic
stainless steel tubes of SGs as an undesired consequence of the industrial application of the AP-CITROX decontamination technology
during the period of 1993–2001. In this paper, we report some comparative findings on the corrosion and surface chemical effects
of the AP-CITROX procedure and the novel decontamination technology elaborated at our institution. On optimizing the operational
parameters the latter technology may become suitable for the effective decontamination of both dismountable (e.g., MCP swivel)
and separable (e.g., SGs) equipments. For this purpose experiments were performed. In this laboratory scale experiments, the
passivity, morphology and chemical compositions of the treated surfaces of tube specimens were investigated by voltammetry,
and SEM–EDX methods, respectively. The SEM–EDX results have revealed that the oxide removal is surprisingly uniform even after
2 or 3 consecutive cycles. The electrochemical studies have provided evidences that no unfavorable tendencies in the general
corrosion state of the tube samples can be detected in the course of the chemical treatments.
The development of innovative clean-up technologies remains a challenge as current procedures have many limitations, such
as being expensive, concentration or pollutant specific, and many others. Natural zeolite of clinoptilolite type was beneficiated
with surfactant octadecylammonium and alginate biopolymers using the sol-gel method. Carbonization process in pyrolysis chamber
combusted organic waste materials and reaching the maximum temperature of 700°C was used for the surface carbonization, respectively.
Resulted zeolite based products were analyzed by FTIR, TG, DTA and examined on the selected aqueous pollutants removal using
the conventional laboratory adsorption experiments. The ability of ODA and alginate linked zeolite of clinoptilolite type
to form complexes with anions (such as nitrate, sulphate, chloride and phosphate) and to remove them from contaminated waters
was validated. Carbon deposition onto clinoptilolite surface originated from the pyrolytic carbon-rich waste combustion simulated
the new zeolite based hybrid to active coke, adsorption efficiency of which towards phenol was approved. Thermogravimetric
analyses of the advanced zeolite-based adsorbents were accomplished to find out how temperature resistant are the novel zeolite
based materials in respect to the original, untreated one. While the native clinoptilolite indicated according to DTA analysis
one broad endothermic response around 100–130°C, resulted from the loss of adsorbed water, by the ODA-modified clinoptilolite
was except this DTA peak, the broad exothermic response started from 370 up to 560°C observed. This DTA profile is assumed
to record a slowly breakdown of attached ODA surfactant and sequential loss of mass due to continual heating of sample under
8-O-Acetylharpagide is the main active component of the herb Ajuga decumbens, which possesses anti-tumor, anti-virus, and anti-inflammation properties. In this study, ultra-performance liquid chromatography–tandem mass spectrometry (UPLC–MS/MS) was used to measure the concentration of 8-O-acetylharpagide in mouse blood, with subsequent investigation of the pharmacokinetics of the drug after intravenous or oral administration. Shanzhiside methyl ester was used as an internal standard, and the acetonitrile precipitation method was used to process the blood samples. Chromatographic separation was achieved using an ultra-performance liquid chromatography ethylene-bridged hybrid (UPLC BEH) column (2.1 mm × 50 mm, 1.7 μm) with a gradient methanol–water mobile phase (containing 0.1% formic acid). The flow rate was 0.4 mL/min, and the elution time was 5.0 min. 8-O-Acetylharpagide was quantitatively measured using electrospray ionization (ESI) tandem mass spectrometry in multiple reaction monitoring (MRM) mode with positive ionization. The result indicated that, within the range of 5–500 ng/mL, the linearity of 8-O-acetylharpagide in mouse blood was satisfactory (r > 0.995), and the lower limit of quantification (LLOQ) was 5 ng/mL. Intra-day precision relative standard deviation (RSD) of 8-O-acetylharpagide in blood was lower than 9%, and the inter-day precision RSD was lower than 13%. The accuracy range was between 94.3% and 107.1%, average recovery was higher than 91.3%, and the matrix effect was between 100.8% and 110.8%. This analytical method was sensitive and fast with good selectivity and was successfully applied to perform pharmacokinetic studies of 8-O-acetylharpagide in mice. The bioavailability of 8-O-acetylharpagide was 10.8%, and the analysis of the primary pharmacokinetic parameters after oral and intravenous administration indicated that 8-O-acetylharpagide had a significant first pass effect after oral administration.
In order to interpret cosmogenic radionuclides in extraterrestrial matter one has to differentiate between p- and α-induced
reactions with solar (SCR) and with galactic (GCR) cosmic rays. Our earlier studies have shown that for a satisfactory description
of GCR-interactions with dense matter rather few but characteristic high energy cross sections are required. In contrast,
for the low and medium energy SCR-production a detailed knowledge of the respective nuclear reactions is needed. In the present
study, excitation functions are presented for 39 p-induced reactions on Ni, Fe, Mn, Cr and Ti, which contribute to SCR-produced
radionuclides (44≤A≤59) at energies up to 200 MeV. The excitation functions are based mainly on our own cross section measurements,
partly on hybrid model predictions and to a lesser extent on experimental data from other authors. Based on these excitation
functions, depth profiles for the proton induced SCR-production of46Sc,44Ti,48V,51Cr,52Mn,53Mn,54Mn,55Fe,56Co,57Co,58Co,60Co and59Ni from the 5 major targets mentioned before in extraterrestrial matter are calculated, assuming normal lunar surface conditions.
Typical rigidities were adopted for the solar proton fluxes, ranging from 50 to 150 MV, which cover the rigidity values commonly
observed in solar flares. In order to derive depth dependent p-fluxes from calculations of the energy loss of incoming particles,
rather large differences in the respective chemical compositions had to be considered. The theoretical profiles are compared
with experimental data from lunar samples, and several cosmochemical applications are discussed. They range from the study
of single solar flare events by short-lived radioisotopes to the investigation of supposed long-term variations of the solar
flare activity on a large times-cale of millions of years. The latter is possible by comparing the production rates of very
long-lived nuclides (as for example53Mn with T=3,8·106 y) with that of short- or medium-lived nuclides. In this respect, the particular importance of44Ti (T-47.3 y) for measuring today's mean solar flare activity is pointed out. In general, the depth dependent production rates
established in this work enable one to estimate the SCR-contributions to cosmogenic radionuclides from the respective target
elements, thus providing a basis for a better understanding of the solar cosmic ray interaction with extraterrestrial matter.
Authors:Songsheng Lu, Zhiqiang Guo, Caicai Zhang, and Shouwei Zhang
MX-80 bentonite was characterized by XRD and FTIR in detail. The sorption of Th(IV) on MX-80 bentonite was studied as a function
of pH and ionic strength in the presence and absence of humic acid/fulvic acid. The results indicate that the sorption of
Th(IV) on MX-80 bentonite increases from 0 to 95% at pH range of 0–4, and then maintains high level with increasing pH values.
The sorption of Th(IV) on bentonite decreases with increasing ionic strength. The diffusion layer model (DLM) is applied to
simulate the sorption of Th(IV) with the aid of FITEQL 3.1 mode. The species of Th(IV) adsorbed on bare MX-80 bentonite are
consisted of “strong” species
at pH > 4. Similar species of Th(IV) adsorbed on FA bound MX-80 bentonite are observed as on FA bound MX-80 bentonite. The
sorption isotherm is simulated by Langmuir, Freundlich and Dubinin–Radushkevich (D–R) models, respectively. The sorption mechanism
of Th(IV) on MX-80 bentonite is discussed in detail.
EETHARAMA , N. S. , 2008 . Characterizing phenology and growth stages of sorghum hybrids. In: Sorghum improvement in the new millenium. (Eds.: REDDY BELUM, V. S., RAMESH, S., ASHOK KUMAR, A. & GOWDA, G. L. L.) 16–22. Patancheru. India
Authors:Andrei Jitianu, Kristin Lammers, Georgia A. Arbuckle-Kiel, and Lisa C. Klein
Silica-based organic–inorganic hybrid nanocomposites can be formed with a stable inorganic framework combined with a variety of organo-functional groups [ 1 ]. The physical and chemical properties of the
Authors:S. D. Sharma, K. G. Varshney, and S. C. Mojumdar
transformation at around 250 °C which permits its use as a catalyst for certain reactions when employed at this temperature. Recently, they reported synthesis, characterisation and analytical applications of some new hybrid fibrous ion exchangers of Th(IV) [ 5
Szabadföldi P—Zn műtrágyázási tartamkísérletünket 1978 őszén állítottuk be löszön képződött, mély humuszrétegű, vályog mechanikai összetételű karbonátos csernozjom talajon, Intézetünk nagyhörcsöki kísérleti telepén. A talaj szántott rétege 5 % CaCO3-ot, 3 % humuszt tartalmaz; Ca, Mg, Mn és Cu elemekkel kielégítően, N és K elemekkel közepesen, P és Zn elemekkel gyengén ellátott. A talajvíz 13–15 m mélyen helyezkedik el, a termőhely aszályra hajló, vízmérlege negatív.
A 4P × 3Zn = 12 kezelést 3 ismétlésben, split-plot elrendezésben állítottuk be. A parcellák mérete 4,9x15=73,5 m². Főparcellaként a 0, 100 kg/ha/év, 500 kg/ha/5 év, 1000 kg/ha/5 év P2O5-trágyázás, alparcellaként a 0, 20, 40 kg/ha/5 év Zn-trágyázás szolgált szuperfoszfát és ZnSO4 formájában. Alaptrágyaként az egész kísérletben egységesen 200 kg/ha N-és 200 kg/ha K2O-műtrágyát alkalmaztunk NH4NO3 és KCl formájában. A termesztett kukoricahibrid az Mv-SC 580 volt. Az első 4 év eredményei alapján levonható főbb következtetések:
Kísérleti körülményeink között, ezen a foszforral gyengén ellátott talajon, az évenként adott 100 kg/ha P2O5-trágyázás kielégítheti a kukorica P-igényét. Előretrágyázás formájában ez a mennyiségű foszfor 4–5 évre számolva egyszerre is kiadható. Az 1000 kg/ha feltöltő P2O5-trágyázás gazdaságtalan és Znhiányt indukálva terméscsökkenéshez vezethet. Az AL-oldható P2O5-tartalom optimumát a 100–150 mg/kg érték jelezheti a szántott rétegben.
Az egyoldalú, 1000 kg P2O5/ha adaggal előidézett P-túlsúlyt és szemterméscsökkenést a 40 kg/ha Zn-trágyázással lehetett ellensúlyozni. A KCl+EDTA módszerrel meghatározott Zn-tartalom optimumát 2–3 mg/kg talajbani koncentráció mutatta.
Irodalmi adagokkal összhangban a kukorica kiegyensúlyozott tápláltsági állapotát a 4–6 leveles légszáraz hajtásban mért 0,3–0,5 % P és 30–60 mg/kg Zn, míg a címerhányáskori levél optimális összetételét 0,25–0,40 % P és 25 mg/kg feletti Zn-koncentráció-tartomány jellemezheti. A P/Zn arányának ideális értéke a vegetatív növényi részekben 50–150 közöttire tehető. Amennyiben ez a P/Zn arány jelentősen 200 fölé emelkedik, a Zn-trágyázás hatékony lehet.
A P-túlsúly növelte a meddő tövek előfordulását 1978-ban, amikor szemtelítődés idején (augusztusban) aszály uralkodott. Ebben az évben a termő tövek 13–20 %-a bizonyult terméketlennek.