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81.
KM Varier AM Vinodkumar NVSV Prasad PV Madhusudhana Rao DL Sastry Lagy T Baby MC Radhakrishna NG Puttaswamy JJ Das P Sugathan N Madhavan AK Sinha DO Kataria 《Pramana》1999,53(3):529-533
Large enhancements have been observed in the sub-barrier fusion cross sections for Ti+Ni systems in our previous studies.
Coupled channel calculations incorporating couplings to 2+ and 3− states failed to explain these enhancements completely. A possibilty of transfer channels contributing to the residual enhancements
had been suggested. In order to investigate the role of relevant transfer channels, measurements of one- and two-nucleon transfer
were carried out for 46,48Ti+61Ni systems. The present paper gives the results of these studies. 相似文献
82.
83.
The hyperfine fields Bhf (RbFe), Bhf (SrFe) and Bhf (YFe) have been determined by the low temperature nuclear orientation of dilute samples of83Rb,83,85Sr and85Ym in an iron lattice to be Bhf (RbFe)=+54 (10) kG, Bhf (SrFe)=(?)100 (30) kG and Bhf (YFe)=?226 (10) kG. These results are compared with recent calculations for these fields (1), (2). 相似文献
84.
Alves GA Amato S Anjos JC Appel JA Astorga J Bracker SB Cremaldi LM Dagenhart WD Darling CL Dixon RL Errede D Fenker HC Gay C Green DR Jedicke R Karchin PE Kennedy C Kwan S Lueking LH de Mello Neto JR Metheny J Milburn RH de Miranda JM da Motta Filho H Napier A Passmore D Rafatian A dos Reis AC Ross WR Santoro AF Sheaff M Souza MH Spalding WJ Stoughton C Streetman ME Summers DJ Takach SF Wallace A Wu Z 《Physical review letters》1996,77(12):2388-2391
85.
Direct cryopreservation of overwintering, dormant buds has been applied to nine blackcurrant cultivars, using a 7 day dehydration period at c.-20° C before plunging directly into liquid nitrogen. The buds on shoots thawed from -20° C showed normal development simply by standing them in water and all the cultivars could be successfully recovered (> 58%) by grafting. None of the shoots thawed from liquid nitrogen showed any development after standing in water and all of the grafts failed. Shoots thawed from liquid nitrogen showed significant damage to xylem transport, and the cortical tissues necessary fro successful grafting showed significant loss of membrane semipermeability. However, buds excised from shoots immediately after thawing from liquid nitrogen were viable and could be recovered using in vitro culture. Survival ranged from 88 to 55%, depending upon cultivar. 相似文献
86.
87.
Typically, X‐ray absorption near‐edge structure measurements aim to probe the linear attenuation coefficient. These measurements are often carried out using partial fluorescence yield techniques that rely on detectors having photon energy discrimination improving the sensitivity and the signal‐to‐background ratio of the measured spectra. However, measuring the partial fluorescence yield in the soft X‐ray regime with reasonable efficiency requires solid‐state detectors, which have limitations due to the inherent dead‐time while measuring. Alternatively, many of the available detectors that are not energy dispersive do not suffer from photon count rate limitations. A filter placed in front of one of these detectors will make the energy‐dependent efficiency non‐linear, thereby changing the responsivity of the detector. It is shown that using an array of filtered X‐ray detectors is a viable method for measuring soft X‐ray partial fluorescence yield spectra without dead‐time. The feasibility of this technique is further demonstrated using α‐Fe2O3 as an example and it is shown that this detector technology could vastly improve the photon collection efficiency at synchrotrons and that these detectors will allow experiments to be completed with a much lower photon flux reducing X‐ray‐induced damage. 相似文献
88.
The achievable-region approach, based on strong conservation laws, has most often been applied to stochastic scheduling and
other control problems in the context of performance measures that are steady-state expected quantities. For some problems,
however, strong conservation laws hold for performance measures at every time point on every sample path. We exploit this
property to study optimal control for certain scheduling problems on a sample-path basis. Examples include preemptive scheduling
to minimize a weighted sum of work in the system in each class, nonpreemptive scheduling to minimize a weighted sum of the
number of customers in each class (when all classes have the same service-time distribution), and scheduling the processing
of fluid in a multiclass fluid system operating in a random environment. The last problem is solved by considering the related
Skorohod problem and its minimal solution.
This revised version was published online in June 2006 with corrections to the Cover Date. 相似文献
89.
Ban Xuan Dong Anton Li Joseph Strzalka Gila E. Stein Peter F. Green 《Journal of Polymer Science.Polymer Physics》2017,55(1):39-48
The morphological structure of poly(3‐hexylthiophene) (P3HT) thin films deposited by both Matrix Assisted Pulsed Laser Evaporation (MAPLE) and solution spin‐casting methods are investigated. The MAPLE samples possessed a higher degree of disorder, with random orientations of polymer crystallites along the side‐chain stacking, π–π stacking, and conjugated backbone directions. Moreover, the average molecular orientations and relative degrees of crystallinity of MAPLE‐deposited polymer films are insensitive to the chemistries of the substrates onto which they were deposited; this is in stark contrast to the films prepared by the conventional spin‐casting technique. Despite the seemingly unfavorable molecular orientations and the highly disordered morphologies, the in‐plane charge carrier transport characteristics of the MAPLE samples are comparable to those of spin‐cast samples, exhibiting similar transport activation energies (56 vs. 54 meV) to those reported in the literature for high mobility polymers. © 2016 Wiley Periodicals, Inc. J. Polym. Sci., Part B: Polym. Phys. 2017 , 55, 39–48 相似文献
90.
For deep injection of CO2 in thick saline formations, the movements of both the free gas phase and dissolved CO2 are sensitive to variations in vertical permeability. A simple model for vertical heterogeneity was studied, consisting of
a random distribution of horizontal impermeable barriers with a given overall volume fraction and distribution of lengths.
Analytical results were obtained for the distribution of values for the permeability, and compared to numerical simulations
of deep CO2 injection and convection in heterogeneous formations, using multiple realizations for the permeability distribution. It is
shown that for a formation of thickness H, the breakthrough times in two dimensions for deep injection scale as H
2 for moderate injection rates. In comparison to heterogeneous shale distributions, a homogeneous medium with equivalent effective
vertical permeability has a longer breakthrough time for deep injection, and a longer onset time for convection. 相似文献