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1.
The neutron deficient nucleus94Pd was identified and studied for the first time by in-beam spectroscopy. An I=(14+) isomer with t1/2=0.8 (2) s was observed in a recoil catcher setup inside the multi-detector -array OSIRIS. Filter detectors for neutrons and charged particles were used to identify the (2p2n) exit channel of the reaction58Ni+40Ca, populated with only 0.06% of the total evaporation residue cross section. The structure of the isomer is discussed within the frame work of shell model calculations in the (p1/2,g9/2) model space with emphasis on the g 9 2/2 T=0, I=1,9 pairing two-body matrix elements.Communicated by: D. Schwalm  相似文献   
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An investigation was undertaken to measure the trace elements in the blood samples by particle induced X-ray emission (PIXE). From the measured concentrations an attempt was made to group the blood specimens by pattern recognition methods as a first step in the search for a possible correlation between the geographical area of domicile and trace elemnt composition. The trend indicated that children with lower Fe and Br contents were similar in their trace element pattern, were predominantly from two district, had lower ferritin values and were breast fed longer than the remaining children in the survey.  相似文献   
4.
We report the first experimental results on a high-gain harmonic-generation (HGHG) free-electron laser (FEL) operating in the ultraviolet. An 800 nm seed from a Ti:sapphire laser has been used to produce saturated amplified radiation at the 266 nm third harmonic. The results confirm the predictions for HGHG FEL operation: stable central wavelength, narrow bandwidth, and small pulse-energy fluctuation.  相似文献   
5.
The IMPAD technique has been used to determine the Larmor precessions of the83Y 595 keV 13/2+ and 145 keV 7/2+ states in iron. The net precessions found are ωτ(13/2+)=−9(2) mrad and ωτ(7/2+)=−92(5) mrad, leading to g-factors, g(13/2+)=+1.3(4) and g(7/2+)=+0.61(18). These results are discussed in terms of a partially decoupled [422]5/2+ Nilsson band.  相似文献   
6.
We demonstrate 12-ps pulses with up to 0.6-mJ pulse energy at repetition rates of 50 kHz and 100 kHz from a Nd:YVO4 slab amplifier built in a simple four-pass configuration. Excellent noise performance with pulse energy fluctuations below 0.8% rms has been achieved by using 10-μJ seed pulses from a highly stable industrial laser system and moderate gain (30–46) in the slab amplifier.  相似文献   
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The reaction58Ni(36Ar, 4p)90Mo has been studied at a beam energy of 149 MeV. A detector array consisting of the OSIRIS spectrometer (12 Compton-suppressed Ge detectors), four charged-particleδE detectors and seven NE-213 neutron detectors at the VICKSI accelerator in Berlin has been used to measure the gamma radiation inγγ- and particle-γγ-coincidence mode. An additional Ge detector was placed at 162? to the beam direction to provide information on DCO ratios. The level scheme of90Mo has been extended up to an excitation energy of about 12 MeV and probable spin 23?. Some 70 transitions and 40 levels have been newly identified. Spin assignments have been proposed on the basis of measured DCO ratios. Shell model calculations in a model space consisting of the proton 1f 5/2, 2p 3/2, 2p 1/2, and 1g 9/2 orbits and the neutron 2p 1/2, 1g 9/2, 1g 7/2, 2d 5/2, 2d 3/2, and 3s 1/2 orbits with some truncation were made for states above 9? and the predicted structure of these states is discussed.  相似文献   
8.
Deformation parameters of the positive parity yrast band and negative parity bands in83Zr are deduced from lifetimes andE2/M1 mixing ratios. Lifetimes of high spin states have been determined from recoil distance Doppler shift and Doppler shift attenuation measurements using the54Fe(32S,2pnγ) 83Zr reaction. Ten lifetimes and five lifetimes limits were determined. The positive parity band, built on theg 9/2 K=5/2 orbital has an average deformation ¦β 2¦=0.28(2), and shows a reduction ofE2 transition strengths in the observed backbend region at Iπ≈21/2+. In contrast, theE2 strengths in the negative parity states show a steady increase up to Iπ≈=15/2?. These states are more strongly deformed than the positive parity states (¦β 2¦=0.33(3)). TheE2/M1 mixing ratios show that the negative parity band hasK=3/2 and is prolate, and favour oblate deformation for the positive parity yrast band. In theK=1/2? band theE2 strength of the 7/2?→3/2? transition yields a deformation ¦β 2¦=0.26(5). The band structure is compared with calculations within the Hartree-Fock Bogoliubov cranking model.  相似文献   
9.
By means of the reaction40Ca (36Ar, 3p), the band structure of73Br connected with the g9/2 single-particle proton orbit has been investigated up to Iπ=33/2+. In contrast to the core spectrum in72Se, which is dominated by the coexistance of different shapes, the nucleus73Br features rotational bands with slowly increasing moments of inertia. Their deformation β2=0.40(2) has been deduced from recoil distanc lifetime measurements.  相似文献   
10.
Store-brand products are of increasing importance in retailing, often causing channel conflict as they compete with national brands. Focusing on the interactions that arise in single-manufacturer single-retailer settings, previous research suggests that one main driver of store-brand profitability to the retailer is that it leads to a reduction of the national-brand wholesale price. Under retail competition, the Robinson Patman Act then introduces an interesting trade-off: A retailer that introduces a store brand incurs the associated costs and risks, while sharing this benefit with its competition. We show that the resulting interactions can cause retailers to play “chicken”, either of them preferring a store-brand introduction by the competitor. Such interactions do not arise in channels with a single retailer, as has been the object of most previous research, and we show that some of the key insights derived from single-retailer models fail to hold when retailers compete. We conduct a numeric study, and our findings suggest that retailers are more likely to randomize their store-brand introduction strategies when customers have strong store preferences, and when the retailers’ store-brand products are similar to the national-brand product in terms of customer valuations and production cost.  相似文献   
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