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131.
Christina Conroy 《Acta Analytica》2008,23(4):367-372
In his “Space, supervenience and substantivalism”, Le Poidevin proposes a substantivalism in which space is discrete, implying
that there are unmediated spatial relations between neighboring primitive points. This proposition is motivated by his concern
that relationism suffers from an explanatory lacuna and that substantivalism gives rise to a vicious regress. Le Poidevin
implicitly requires that the relationist be committed to the “only x and y” principle regarding spatial relations. It is not obvious that the relationist is committed to this principle in such a context.
An additional motivation for Le Poidevin's argument, that space should be considered to be discrete, is that he believes that
substantivalists are committed to a vicious regress. I show that the regress is in fact not of the vicious variety. These
two main arguments show that Le Poidevin's suggestion that we drop the density postulate for space is unnecessary.
相似文献
Christina ConroyEmail: |
132.
不同年份窖泥细菌16S rDNA系统发育分析 总被引:1,自引:0,他引:1
本研究直接提取5、10、20、50年窖泥细菌总DNA,扩增16SrDNA并构建克隆文库后进行系统发育分析.结果表明,随着年份增加,细菌多样性指数呈现出先增加后略有下降最后回升稳定的趋势;198个阳性克隆子划分成43个分类操作单位(OTUs),按优势顺序依次为Firmicutes、Bacteroidetes、Chloroflexi、unclassified Bacteria、Proteobacteria、Tenericutes、Actinobacteria、Planctomycetes和Spirochaetes.不同年份窖泥中优势菌不同,在5、50年窖泥中紫单胞菌科占优势,而在10、20年窖泥中梭菌目占优势.其中Petrimonas、Rikenellaceae、Syntrophomonadaceae、Clostridium、Lactobacillus等细菌均有发现,它们在窖泥老熟和白酒风味物质生成过程中发挥着重要作用. 相似文献
133.
本文对不定方程x2+y2=z2给出了四个推广,并用一种统一的解法对这四个推广给出了解答. 相似文献
134.
Guang Lin RANG Zhi Yuan HUANG 《数学学报(英文版)》2007,23(5):895-904
In this paper a complete proof for the existence of generalized operators satisfying abstract 02 dynamical equations of quantum motions δ^2/δt^2Ф(t, x) + ( △- m^2)Ф(t, x) = -λ :Ф^3(t, x), subject to a suitable initial condition, is given under the framework of white noise analysis. Also some important commutation relations related to Ф44 quantum fields are discussed and proved in detail. 相似文献
135.
136.
X.-F. Pang 《The European Physical Journal B - Condensed Matter and Complex Systems》1999,10(3):415-428
The influence of a soliton on the properties of the M?ssbauer effect resulting from the gamma-active nuclei situated at lattice
sites in quasi-one-dimensional anharmonically organic molecular chains, in which the active nuclei emit gamma-photons, has
been theoretically studied by a quantum vibrational model. An expression for the gamma-radiated M?ssbauer transition probability
as a function of the temperature and non-linear interaction has been obtained. Finally we give some new properties of this
effect from numerical calculation in such a case, which present a way to experimentally confirm the soliton existence in molecular
crystals.
Received 9 April 1998 and Received in final form 11 December 1998 相似文献
137.
M.A. Continentino J.C. Fernandes R.B. Guimar aes H.A. Borges A. Sulpice J.-L. Tholence J.L. Siqueira J.B.M. da Cunha C.A. dos Santos 《The European Physical Journal B - Condensed Matter and Complex Systems》1999,9(4):613-618
The system Cu2FeO2BO3 is an oxyborate belonging to the family of the ludwigites. In this paper we present AC susceptibility, magnetization measurements
and M?ssbauer spectroscopy on this material which allows for a complete characterization of its complex magnetic behavior.
We find an hierarchy of interactions which clearly defines three regimes with decreasing temperature. These are associated
with, the freezing of the Fe moments, the antiferromagnetic ordering of the Cu sub-lattice and finally the coupling between
both systems.
Received 25 September 1998 相似文献
138.
G.G.M. Coppa A. D'Angola 《The European Physical Journal D - Atomic, Molecular, Optical and Plasma Physics》1999,6(4):533-539
The paper deals with the stationary distribution of charged particles moving in a material medium, having scattering and absorption
properties, in which a uniform electric field is present. The purpose of the work is finding analytical solutions in simplified
but physically significant situations and comparing different approximations based on a spherical-harmonics expansion of the
velocity distribution.
Received: 28 July 1998 相似文献
139.
V. Rusanov H. Winkler C. Ober A.X. Trautwein 《The European Physical Journal B - Condensed Matter and Complex Systems》1999,12(2):191-198
M?ssbauer studies were performed on single crystals of guanidinium nitroprusside with different orientations of their principal
crystallographic axes (a, b, c) with respect to the incident radiation. The markedly anisotropic Lamb-M?ssbauer factor f
LM
, i.e.
f
LM
(a) = 0.118(8), f
LM
(b) = 0.174(8), f
LM
(c) = 0.202(8) is in contrast to that of nitroprussides with inorganic anions. The observed anisotropy is ascribed to the anisotropic
vibrational mean-square displacement of the nitroprusside anions as a whole which is due to the specific packing of both,
anions and cations, as well as the very weak chemical bonding between the ions, typical only for guanidinium nitroprusside.
The vibrational anisotropy of iron atoms in barium nitroprusside that has been observed by X-ray structural investigations
has a different origin and therefore does not result in an anisotropic Lamb-M?ssbauer factor. We have also investigated metastable
states in guanidinium nitroprusside that have been populated by means of incoherent irradiation from light-emitting diodes.
With a specific orientation of the guanidinium nitroprusside single crystal a population of the metastable states up to 26%
could be achieved. Populations of comparable size on lithium, sodium and potassium nitroprussides have only been reached using
coherent laser irradiation.
Received 15 December 1998 and Received in final form 3 March 1999 相似文献
140.
本文对非线性泛函分析中著名的Amann三解定理作了本质性的改进,并将其结果应用到核函数不恒为正的Hammerstein型积分方程,得到了新的结论. 相似文献