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The centrosymmetric title compound, [Cd2{CH3OC6H4P(OC5H9)S2}4], features an eight‐membered [? Cd? S? P? S? ]2 ring owing to the presence of bridging dithiolate ligands. Tetrahedral coordination geometries for cadmium are completed by chelating ligands. Copyright © 2004 John Wiley & Sons, Ltd. 相似文献
4.
O. Yilmaz F. Y. Lambrecht N. Gokmen S. Erbayraktar K. Durkan 《Journal of Radioanalytical and Nuclear Chemistry》2007,273(2):311-313
The aim of the present study was to demonstrate the possible transplacental transmission of 131I labeled recombinant human erythropoietin (131I-rh-EPO) in pregnant rats and its distribution through maternal and fetal organs. Six Wistar Albino Rats in their pregnancy
of 18 days were used 131I labeled recombinant human erythropoietin (specific activity = 2.4 μCi/IU) was injected into the tail vein of rats. After
30 minutes labeled erythropoietin infusion maternal stomach, kidney, lung, liver, brain and heart as well as fetus were removed.
Then, the same organs were removed from each fetus. Measuring weight of maternal and fetal organs as well as placenta were
followed by radioactivity count via Cd(Te) detector. 131I labeled recombinant human erythropoietin was found to be able to pass rat placenta and its distribution order in fetal organs
was similar to those of maternal organs. Besides, as measurements were performed closer to cornu uteri, uptakes were decreasing
in every fetus and its corresponding placenta. 相似文献
5.
G. Lefvre A. Hamza M. Fdoroff F. Carrette H. Cordier 《Colloids and surfaces. A, Physicochemical and engineering aspects》2006,280(1-3):32-38
A simple experimental approach was developed to determine the adhesion rate of particles onto massive substrate. Turbidimetry measurements are used to follow the evolution of particle concentration in a suspension in dynamic contact with the walls of a vessel made of different materials. This method allows to rapidly obtain qualitative results about the adhesion of metallic oxides particles on massive substrates. Adhesion of particles of charged latex onto glass was used to validate the approach and was shown to be a method to determine isoelectric points (IEP) of massive substrates. Then, the adhesion of an iron oxide (hematite) particles onto several substrates was studied to determine the reactivity of current labware (glass, polypropylene) and on a metal (aluminum) commonly found in industrial fouling problems. Adhesion of hematite was found to be pH-dependant, and occurs only below ca. 6 (glass) or 7 (polypropylene), and above 7 (aluminum). DLVO calculations were performed to model the hematite/water/glass system and are consistent with the experimental results. Experiments at temperature 7–50 °C have shown an increasing of the adhesion rate from 7 to 40 °C, then a constant value until 50 °C. 相似文献
6.
Validation and verification of social processes within agent-based computational organization models 总被引:1,自引:0,他引:1
Levent Yilmaz 《Computational & Mathematical Organization Theory》2006,12(4):283-312
The use of simulation modeling in computational analysis of organizations is becoming a prominent approach in social science
research. However, relying on simulations to gain intuition about social phenomena has significant implications. While simulations
may give rise to interesting macro-level phenomena, and sometimes even mimic empirical data, the underlying micro and macro
level processes may be far from realistic. Yet, this realism may be important to infer results that are relevant to existing
theories of social systems and to policy making. Therefore, it is important to assess not only predictive capability but also
explanation accuracy of formal models in terms of the degree of realism reflected by the embedded processes. This paper presents
a process-centric perspective for the validation and verification (V&V) of agent-based computational organization models.
Following an overview of the role of V&V within the life cycle of a simulation study, emergent issues in agent-based organization
model V&V are outlined. The notion of social contract that facilitates capturing micro level processes among agents is introduced
to enable reasoning about the integrity and consistency of agent-based organization designs. Social contracts are shown to
enable modular compositional verification of interaction dynamics among peer agents. Two types of consistency are introduced:
horizontal and vertical consistency. It is argued that such local consistency analysis is necessary, but insufficient to validate
emergent macro processes within multi-agent organizations. As such, new formal validation metrics are introduced to substantiate
the operational validity of emergent macro-level behavior.
Levent Yilmaz is Assistant Professor of Computer Science and Engineering in the College of Engineering at Auburn University and co-founder
of the Auburn Modeling and Simulation Laboratory of the M&SNet. Dr. Yilmaz received his Ph.D. and M.S. degrees from Virginia
Polytechnic Institute and State University (Virginia Tech). His research interests are on advancing the theory and methodology
of simulation modeling, agent-directed simulation (to explore dynamics of socio-technical systems, organizations, and human/team
behavior), and education in simulation modeling. Dr. Yilmaz is a member of ACM, IEEE Computer Society, Society for Computer
Simulation International, and Upsilon Pi Epsilon. URL: http://www.eng.auburn.edu/~yilmaz 相似文献
7.
Budde F Hamza AV Ferm PM Ertl G Weide D Andresen P Freund H 《Physical review letters》1988,60(15):1518-1521
8.
Jale Müslehiddino?lu Yusuf Uluda? Hilmi Önder Özbelge Levent Yilmaz 《Journal of membrane science》1998,140(2):396-266
Performance of continuous polymer enhanced ultrafiltration (PEUF) method was investigated for removal of mercury and cadmium from binary mixtures. This method includes the addition of polyethyleneimine (PEI) as a water soluble polymer to bind the metals, which was followed by ultrafiltration operation performed on both laboratory and pilot scale systems. The influence of various operating parameters such as temperature, metal/polymer ratio, presence of calcium ions and pH on retention of metals and permeate flux was investigated. To investigate the possibility of selective separation of mercury and cadmium, experiments were conducted for binary solutions at different pH and loading ratios. It was seen that the retention of mercury decreased and permeate flux increased when the temperature increased. The increased pH and decreased metal/polymer ratio, loading (L), resulted in higher retention of both metals. Shapes of retention vs. pH or L curves were very similar for both metals. Retentions stay almost constant at a value very close to unity until a critical L or pH value was reached, then, R decreases almost linearly with L or pH. However, retention of cadmium was affected more than that of mercury as the pH decreased and L increased. This leads to the selective separation of mercury and cadmium. At low pH values (about 5) and at high L values (about 0.3), mercury was removed by ultrafiltration operation while almost all cadmium passed through the membrane. At pH 5.5 and cadmium/polymer ratio about 0.35 and mercury/polymer ratio about 0.39, the highest separation factor was obtained as 49. 相似文献
9.
In this work, some results related to superatomic Boolean interval algebras are presented, and proved in a topological way. Let x be an uncountable cardinal. To each I
x, we can associate a superatomic interval Boolean algebra B
I of cardinality x in such a way that the following properties are equivalent: (i) I
I
x, (ii) B
I is a quotient algebra of B
J, and (iii) there is an homomorphism f from B
J into B
I such that for every atom b of B
I, there is an atom a of B
J satisfying f(a)=b. As a corollary, there are 2
x
isomorphism types of superatomic interval Boolean algebras of cardinality x. This case is quite different from the countable one. 相似文献
10.
Non-covalently molecularly imprinted polymers (MIPs) for beta2-amino acids were prepared for the first time. N-(2-chlorobenzyloxycarbonyl)-(R)-beta2-homophenylalanine (N-2-ClZ-(R)-beta2-HPhe) was imprinted with methacrylic acid (MAA) and/or 4-vinylpyridine (4-VPy) as the functional monomers, with ethylene glycol dimethacrylate (EDMA) as the cross-linker. The MIPs made with different ratios of MAA:4-VPy were studied in HPLC mode. The results show that MIPs made with 4-VPy yielded the best chiral separation factor (alpha= 1.86) for the template molecule. The importance for an efficient separation of pi-stacking interactions between the MIPs and the template molecule is demonstrated. Racemates of Z-alpha-amino acids and beta-amino acid analogues of the template were either not or poorly resolved by the MIPs, thus demonstrating the close three-dimensional complementarity of the MIPs' recognition sites with the template. 相似文献