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101.
RE Tribble A Azhari HL Clark CA Gagliardi Y-W Lui AM Mukhamedzhanov A Sattaroy X Tang L Trache V Burjan J Cejpek V Kroha S Piskor J Vincour F Carstoiu 《Pramana》1999,53(3):585-594
S-factors for direct capture reactions can be found at astrophysical energies from asymptotic normalization coefficients which
provide the normalization of the tail of the overlap function. For example the overlap for 8B → 7Be+p defines the S-factor for 7Be (p, γ)8B. Peripheral transfer reactions offer a technique to determine these asymptotic normalization coefficients. As a test of
the technique, the 16O(3He, d)17F reaction has been used to determine asymptotic normalization coefficients for transitions to the ground and first excited
states of 17F. The S-factors for 16O(p, γ)17F calculated from these 17F → 16O+p asymptotic normalization coefficients are found to be in very good agreement with recent measurements. Following the same
technique, the 10B(7Be, 8B)9Be and 14N(7Be, 8B)13C reactions have been used to measure the asymptotic normalization coefficient for 7Be(p, γ)8B. This result provides an indirect determination of S
17(0). 相似文献
102.
A. Ruff A. Krynicki R. C. Parker A. Inst F. J. Siddle N. N. Murty H. K. Sen H. Weinberger H. Gardner E. W. Plowman K. Würth G. Schröder C. E. Foss J. A. V. Fairbrother R. G. W. Croney E. A. Becker L. I. Belenki I. I. Ssokolow M. Je. Kasanskaja N. Bunzelman A. Iljina W. Schwedowa G. Agibalowa M. Déribéré F. Vlès E. Vellinger J. Kasarnowsky K. Allison J. McGray A. Nicollet 《Analytical and bioanalytical chemistry》1941,121(7-8):274-281
103.
E Torgnes V Gunnerud E Hagem M Rönnqvist B Foss 《The Journal of the Operational Research Society》2012,63(7):950-968
This article discusses the optimization of a petroleum production allocation problem through a parallel Dantzig–Wolfe algorithm. Petroleum production allocation problems are problems in which the determination of optimal production rates, lift gas rates and well connections are the central decisions. The motivation for modelling and solving such optimization problems stems from the value that lies in an increased production rate and the current lack of integrated software that considers petroleum production systems as a whole. Through our computational study, which is based on realistic production data from the Troll West field, we show the increase in computational efficiency that a parallel Dantzig–Wolfe algorithm offers. In addition, we show that previously implemented standard parallel algorithms lead to an inefficient use of parallel resources. A more advanced parallel algorithm is therefore developed to improve efficiency, making it possible to scale the algorithm by adding more CPUs and thus approach a reasonable solution time for realistic-sized problems. 相似文献
104.
Ogaki R Bennetsen DT Bald I Foss M 《Langmuir : the ACS journal of surfaces and colloids》2012,28(23):8594-8599
The development of cost-effective methodologies for the precise nanometer-scale positioning of biomolecules permits the low-cost production of various biofunctional devices for a range of biomedical and nanotechnological applications. By combining colloidal lithography and the mussel-inspired multifunctional polydopamine coating, we present a novel parallel benchtop method that allows rapid nanoscale patterning of proteins without the need for electrically powered equipment in the fabrication process. The PDA-immobilized binary nanopattern consisting of BSA surrounded by PLL-g-PEG is fabricated over a large area, and the integrity of the pattern is confirmed using AFM and FM. 相似文献
105.
We establish the partial regularity of solutions to quasilinear parabolic systems with elliptic part that grows subquadratically. More precisely, it is shown that there is an open subset with full measure, of the solution’s domain, on which the solution is H?lder continuous. A key feature in this article is that we only require the coefficients of the system to be continuous with respect to the first two arguments. To prove the result, we use the A-caloric approximation method and an intrinsic scaling. To accommodate the subquadratic growth an adaptation of the A-caloric approximation lemma is also provided. 相似文献
106.
Manganese oxide films have been grown by atomic layer deposition and investigated using electron diffraction and high-resolution electron microscopy (HREM). The films were deposited on the (001) surface of monocrystalline α-Al2O3. The films were found to consist of an ordered version of the hexagonal ε-MnO2 (Akhtenskite) type. Using X-ray diffraction, the cell parameters were determined to be a?=?2.75(2)?Å and c?=?4.302(5)?Å. The films are epitaxial with a specific orientation relative to the Al2O3 substrate. The [210] and [001] axes of ε-MnO2 are parallel to the [110] and [001] axes of α-Al2O3, respectively. Evidence of cation ordering was found by parallel beam electron diffraction. The ordered domains are needle shaped with widths of 2–10?nm. The unit cell of the ordered structure was found to be orthorhombic with cell dimensions a?=?2.75, b?=?4.76, c?=?4.302?Å and space group Pmnn (No. 58). 相似文献
107.
108.
Consider a queueing system in which arriving customers are placed on a circle and wait for service. A traveling server moves at constant speed on the circle, stopping at the location of the customers until service completion. The server is greedy: always moving in the direction of the nearest customer. Coffman and Gilbert conjectured that this system is stable if the traffic intensity is smaller than 1; however, a proof or counterexample remains unknown. In this review, we present a picture of the current state of this conjecture and suggest new related open problems. 相似文献
109.
为了实现采摘机器人在复杂的自然场景下正确识别树上果实,来完成果实采摘,研究了不同环境下柑橘的识别方法.针对复杂的自然环境的影响及传统方法的局限性,在可见光和近红外区域择选5个特征波长滤波片,采集得到5幅滤波后的图像,并利用光谱角分类算法完成柑橘识别.试验结果表明,在光照角度、光照强度等不同条件下,柑橘的识别准确度达到96%.研究表明,滤波片光谱图像技术结合光谱角分类算法可以有效地识别自然场景下的成熟柑橘. 相似文献
110.