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1

Declustering of Iran earthquake catalog (1983–2017) using the epidemic‑type aftershock sequence (ETAS) model

Davoudi N., Tavakoli H. R., Zare M., Jalilian A.

Acta Geophysica

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2018

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Vol. 66, no. 6

1359--1373

EN

The main goal of this article is to decluster Iranian plateau seismic catalog by the epidemic-type aftershock sequence (ETAS) model and compare the results with some older methods. For this purpose, Iranian plateau bounded in 24°–42°N and 43°–66°E is subdivided into three major tectonic zones: (1) North of Iran (2) Zagros (3) East of Iran. The extracted earthquake catalog had a total of 6034 earthquakes (Mw > 4) in the time span 1983–2017. The ETAS model is an accepted stochastic approach for seismic evaluation and declustering earthquake catalogs. However, this model has not yet been used to decluster the seismic catalog of Iran. Until now, traditional methods like the Gardner and Knopoff space–time window method and the Reasenberg link-based method have been used in most studies for declustering Iran earthquake catalog. Finally, the results of declustering by the ETAS model are compared with result of Gardner and Knopoff (Bull Seismol Soc Am 64(5):1363–1367, 1974), Uhrhammer (Earthq Notes 57(1):21, 1986), Gruenthal (pers. comm.) and Reasenberg (Geophys Res 90:5479–5495, 1985) declustering methods. The overall conclusion is difficult, but the results confirm the high ability of the ETAS model for declustering Iranian earthquake catalog. Use of the ETAS model is still in its early steps in Iranian seismological researches, and more parametric studies are needed.

2

Application of Pulse Doubling in Hexagon-Connected Transformer-Based 20-Pulse AC-DC Converter for Power Quality Improvement

AbdollahiR., Jalilian A.

Przegląd Elektrotechniczny

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2012

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R. 88, nr 10a

153-161

EN

This paper presents a pulse doubling technique in a 20-pulse ac-dc converter which supplies direct torque controlled motor drives (DTCIMD’s) in order to have better power quality conditions at the point of common coupling. The proposed technique increases the number of rectification pulses without significant changes in the installations and yields in harmonic reduction in both ac and dc sides. The 20-pulse rectified output voltage is accomplished via two paralleled ten-pulse ac-dc converters each of them consisting of five-phase diode bridge rectifier. A transformer is designed to supply the rectifiers. The design procedure of magnetics is in a way such that makes it suitable for retrofit applications where a six-pulse diode bridge rectifier is being utilized. Independent operation of paralleled diode-bridge rectifiers, i.e. dc-ripple re-injection methodology, requires a Zero Sequence Blocking Transformer (ZSBT). Finally, a tapped interphase reactor is connected at the output of ZSBT to double the pulse numbers of output voltage up to 40 pulses. The aforementioned structure improves power quality criteria at ac mains and makes them consistent with the IEEE-519 standard requirements for varying loads. Furthermore, near unity power factor is obtained for a wide range of DTCIMD operation conditions. A comparison is made between 6-pulse, 20-pulse, and proposed topology from view point of power quality indices. Simulation results show that input current total harmonic distortion (THD) is less than 5% for the proposed topology at various loads.

PL

W artykule zaprezentowano technikę podwojenia impulsów w 20-pulsowym przekształtniku ac-dc zastosowanym do sterowania momentem silnika. Uzyskano wygładzenie sygnału i mniejszą zawartość harmonicznych. (Zastosowanie podwojenia liczby impulsów w 20-pulsowym przekształtniku AC-DC)

3

Comparison of Three Autotransformer Based 24-Pulse AC-DC Converters Incorporated DC Ripple Reinjection Technique Feeding VCIMD and DTCIMD Loads

Nakhaee S., Jalilian A.

Przegląd Elektrotechniczny

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2011

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R. 87, nr 10

335-339

EN

In this paper, the comparison of star, polygon and zigzag connected autotransformer based 24-pulse AC-DC converters has been presented. They are12-pulse rectifiers incorporated pulse doubling DC ripple re-injection technique supplying VCIMD or DTCIMD load. Simulation results indicate that lower capacitances result in more deterioration in power quality indices at ac mains. In this case, VCIMD has a bitter impact than DTCIMD. Also, using polygon and star connection autotransformers result in lower voltage and current distortions respectively.

PL

Przedstawiono porównanie 24-pulsowego przekształtnika AC-DC z autotransformatorem połączonym w gwiazdę, zygzak lub wielokąt. Obciążeniem jest silnik indukcyjny w konfiguracji VCIMD i DTCIMD. Symulacje pokazały, że otrzymuje się bardzo małe zakłócenie jakości napięcia.

4

Production, quality control and initial imaging studies of [82mRb]RbCl for PET studies

Rowshanfarzad P., Jalilian A., Kiyomarsi M., Sabet M., Karimian A., Moradkhani S., Mirzaii M.

Nukleonika

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2006

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Vol. 51, nr 4

209-215

EN

Rubidium-82m was prepared via 15.4 MeV proton irradiation of a krypton-82 gaseous target (30% enrichment). Washing the target chamber with hot water yielded a Rb-82m containing solution, which was further purified using short column chromatography in order to remove organic/inorganic impurities. The flowthrough was formulated in normal saline for injection. Radionuclide, radiochemical and chemical purity tests were performed prior to administration to rats for imaging (radiochemical yield: 95-97%, radiochemical purity > 97%). Preliminary dual-head coincidence studies were performed to determine the distribution of [82mRb]Rb in normal rats. For biodistribution studies, Rb-81 was injected to rats and tracer accumulation in heart, GI and bladder was determined after sacrification in time intervals. A yield of 1.3 GBq at EOB, 235.7 MBq/mAh was obtained.

5

Production of [103Pd]Bleomycin complex for targeted therapy

Jalilian A., Yari-Kamrani Y., Sadeghi M.

Nukleonika

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2006

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Vol. 51, nr 2

119-123

EN

Due to the anticancer properties of bleomycin (BLM) complexes, production of [103Pd]bleomycin ([103Pd]BLM) was targeted. Palladium-103 (T1/2 = 16.96 d) was produced via the 103Rh(p,n)103Pd nuclear reaction using a natural rhodium target. Proton energy was 18 MeV with 200 mA irradiation for 15 h (final activity 25.9 GBq of 103Pd2+, RCP > 95%, radionuclidic purity > 99%). 103Pd was separated from the irradiated target by anion exchange using a Dowex 1´8 (Cl-)/100-200 mesh resin in the form of Pd(NH3)2Cl2 in order to react with bleomycin to yield [103Pd]BLM. Chemical purity of the final product was in accordance to the accepted limits. [103Pd]BLM was prepared with a radiochemical yield of more than 98% at 80°C in 30 min. The labeling reaction was optimized for time, temperature and ligand concentration. Radiochemical purity of more than 99% was obtained using RTLC with specific activity of about 370 MBq/mmol. The stability of the tracer was checked in the final product and presence of human serum at up to 3 h. The complex was stable in human serum at 37°C up to 2 h of incubation. Biodistribution studies using a SPECT system performed in normal rats in the first 2-3 h.

6

Production and quality control of 66Ga radionuclide

Sabet M., Rowshanfarzad P., Jalilian A., Ensaf M., Rajamand A.

Nukleonika

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2006

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Vol. 51, nr 3

147-154

EN

The purpose of this study was to develop the required targetry and radiochemical methods for production of 66Ga, according to its increasing applications in various fields of science. The 66Zn(p,n)66Ga reaction was selected as the best choice for the production of 66Ga. The targets were bombarded with 15 MeV protons from cyclotron (IBA-Cyclone 30) at the Nuclear Research Center for Agriculture and Medicine (NRCAM) with a current of 180 mA for 67 min. ALICE and SRIM (Stopping and Range of Ions in Matter) nuclear codes were used to predict the optimum energy and target thickness. Targets were prepared by electroplating 95.73% enriched 66Zn on a copper backing. Chemical processing was performed by a no-carrier-added method consisting of ion exchange chromatography and liquid-liquid extraction. Anion exchange chromatography was also used for the recovery of target material. Quality control of the product was carried out in two steps of chemical and radionuclide purity control. The activity of 66Ga was 82.12 GBq at EOB and the production yield was 410.6 MBq/mAh. The radiochemical separation yield was 93% and the yield of chemical recovery of the target material was 97%. Quality control tests showed a radionuclide purity higher than 97% and the amounts of chemical impurities were in accordance with the United States Pharmacopoeiae levels.

7

Preparation of [61Cu]DTPA complex as a possible PET tracer

Jalilian A., Rowshanfarzad P., Sabet M., Kamalidehghan M.

Nukleonika

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2006

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Vol. 51, nr 2

111-117

EN

Copper-61 (T1/2 = 3.33 h) produced via the 64Zn(p,alfa)61Cu nuclear reaction, using a natural zinc target, was separated from the irradiated target material by two ion exchange chromatography steps and was used for the preparation of [61Cu]-diethylenetriaminepentacetate ([61Cu]DTPA) using freshly-prepared DTPA cyclic dianhydride. An electroplated natural zinc layer on a gold-coated copper backing was irradiated with 22 MeV protons (22 12 MeV on the target, 180 miA irradiation, 3.2 h, final activity 220 GBq of 61Cu2+, RCY > 95%, radionuclidic purity > 99%, 60Cu as the only radionuclidic impurity; T1/2 = 23.7 min). Colorimetric methods showed that traces of chemical impurities in the product were below the accepted limits. The solution of [61Cu]DTPA was prepared with a radiochemical yield of more than 80% starting with 61CuOAc ligand at room temperature after 30 min. RTLC showed the radiochemical purity of more than 99%. The specific activity obtained was about 9.1 TBq/mmol. The tracer was shown to be stable in the final product and in the presence of human serum at 37°C up to 3 h.

8

Preparation and biodistribution of [201Tl](III)vancomycin complex in normal rats

Jalilian A., Hosseini M., Karimian A., Saddadi F., Sadeghi M.

Nukleonika

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2006

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Vol. 51, nr 4

203-208

EN

Thallium-201 (T1/2 = 3.04 days) in Tl+ form was converted to Tl3+ cation in presence of O3 in 6 M HCl controlled by RTLC/gel electrophoresis methods. The final evaporated activity was reacted with vancomycin (VAN) in water to yield [201Tl](III)VAN. The best results were obtained at room temperature in water after 30 min with a radiochemical yield > 99%, after mixing the reactants followed by SPE purification using Si Sep-Pak. The studies showed that thallic ion is mostly incorporated into vancomycin with a radiochemical purity of more than 98 š 1% by RTLC. A specific activity of about 4.14 x 1010 Bq/mmol was obtained. Radiochemical purity and stability of 201Tl-VAN in the preparation and in presence of human serum was determined up to 5.5 days. Biodistribution study of 201Tl(III)-vancomycin in normal rats was performed up to 52 h.

9

Development of [66Ga]oxine complex; a possible PET tracer

Jalilian A., Rowshanfarzad P., Sabet M., Rahiminejad-Kisomi A., Rajamand A.

Nukleonika

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2006

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Vol. 51, nr 3

155-159

EN

The aim of this work is development of a possible blood cell labeling agent for ultimate use in PET. Gallium-66 (T1/2 = 9.49 h) is an interesting radionuclide that has a potential for positron emission tomography (PET) imaging of biological processes with intermediate to slow target tissue uptake. Oxine has been labeled with this radionuclide in the form of [66Ga]gallium chloride for its possible diagnostic properties. In this study, 66Ga was produced at a 30 MeV cyclotron (IBA-Cyclone 30) via the 66Zn(p,n)66Ga reaction. The production yield was 445.5 MBq/mAh. The [66Ga]oxine complex was obtained at pH = 5 in phosphate buffer medium at 37°C in 10 min. Radio-TLC showed a radiochemical purity of more than 98 š 2%. The chemical stability of the complex was checked in vitro with a specific activity of 1113 GBq/mmol. The serum stability and log P of the complex were calculated. The produced [66Ga]oxine can be used for diagnostic studies, due to its desirable physico-chemical properties both in vitro and in vivo according to internationally accepted limits.

10

Production and quality control of 65Zn radionuclide

Rowshanfarzad P., Jalilian A., Sabet M.

Nukleonika

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2005

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Vol. 50, nr 3

97-103

EN

Zinc-65 was produced in the Nuclear Research Center for Agriculture and Medicine (NRCAM) by the bombardment of natural copper targets with 30 MeV protons via the 65Cu(p,n)65Zn nuclear reaction. Natural copper was used instead of enriched 65Cu because of the quick decay of undesired radioisotopes. It was also more desirable for cost effectiveness. Cross-section calculations were performed by ALICE nuclear code and the results were compared with the experimental data given in the literature, which showed good agreement. A 160 mi m copper layer target was bombarded with a 150 miA current of 30 MeV protons for 20 min, which resulted in 170 MBq activity of 65Zn product. The yield was 3.4 MBq/miAh. The concentration of the product was 6.8 MBq/ml. Radiochemical separation was carried out by anion exchange chromatography with the yield of about 98%. Quality control of the final product showed a radionuclide purity of more than 98% and no traces of possible impurities (copper) were detected by a colorimetric method with a 1 ppm detection limit using dithizone as the reagent. The materials used for targetry and chemical separation were quite cost-effective.

11

Development of 62Zn bleomycin as a possible PET tracer

Jalilian A., Fateh B., Ghergherehchi M., Karimian A., Moradkhani S., Kamali-Dehghan M., Tabeie F.

Nukleonika

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2005

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Vol. 50, nr 4

143-148

EN

Abstract Bleomycin (BLM), labeled with radioisotopes, is widely used in therapy and diagnosis. In this study, BLM was labeled with 62Zn for oncologic PET studies. The complex was obtained at pH = 2 in saline at 90°C in 25 min. Radio-TLC showed an overall radiochemical yield of 95 97% (radiochemical purity > 97%). Stability of complex was checked in vitro in mice and human plasma/urine. Preliminary in vivo studies were performed to determine complex stability and distribution of 62Zn BLM in normal and fibrosarcoma-bearing mice. 62Zn BLM accumulated significantly in induced fibrosarcoma tumors in mice according to biodistribution/imaging studies. 62Zn BLM can be used in PET oncology studies due to its suitable physicochemical properties as a diagnostic complex in vitro and in vivo. Further studies should be performed for evaluation of the complex behavior in larger mammals.

12

Development of 111In-DTPA-human polyclonal antibody complex for long-term inflammation/infection detection

Jalilian A., Rowshanfarzad P., Shafaii K., Kamali-Dehghan M., Moafian J., Akhlaghi M., Babaii M., Rajabifar S., Mirzaii M.

Nukleonika

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2005

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Vol. 50, nr 3

91-96

EN

Human polyclonal antibody (HIgG) was successively labeled with 111In-indium chloride after residulation with freshly prepared cyclic DTPA-dianhydride. The best results of the conjugation were obtained by the addition of solid DTPA-dianhydride (0.1 0.3 mg) to 100 mi l of the HIgG solution (0.2 0.4 mg/ml) at pH = 6 in phosphate buffer media at 25°C with continuous stirring for 30 min. Radio-thin-layer chromatography showed an overall radiochemical yield of 96 99% at optimized conditions (specific activity = 300 500 MBq/mg, radiochemical purity >98%). The final isotonic 111In-DTPA-HIgG complex was checked by radio-TLC to ensure the formation of only one species followed by filtration through a 0.22 mi filter. Preliminary long-term in vivo studies in turpentine-oil induced inflammation in rat model was performed to determine late complex distribution of the radioimmunoconjugate. The target/skin and target/ blood ratios were 27 and 51 after 24 h, and 23 and 51 after 110 h, showing a high selectivity of the radiopharmaceutical for inflammatory lesions.