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131.
132.
Abstract  Adducts of cadmium(II) dibenzoylmethate, Cd(dbm)2X2 (X = DMSO, H2O) were synthesized and analyzed by thermogravimetric analysis (TGA), differential-scanning calorimetry (DSC), hot-stage microscopy (HSM), single crystal X-ray diffraction, FTIR and Raman spectroscopy, and elemental analysis. Products obtained by thermal decomposition of the two Cd(II) complexes in oxygen, were used for quantitative analysis of cadmium in the adduct molecules. Single-crystal X-ray diffraction analysis of the DMSO adduct revealed that it has cis configuration. The DMSO adduct crystallizes in P21/a space group, a = 17.2494(6) ?, b = 8.3251(4) ?, c = 22.2746(9) ?, β = 93.836(3)°, V = 3191.53(7) ?3, Z = 4. Graphical abstract   Structural, Spectroscopic and Thermal Characterisation of bis (dibenzoylmethanato)Cd(II) Adducts With Dimethylsulfoxide and Water Ivan Halasz, Michaela Horvat, Tomislav Biljan, Ernest Meštrović Two adducts of bis(dibenzoylmethanato)Cd(II), Cd(dbm)2X2 (X = DMSO, H2O) have been synthesized and characterized.   相似文献   
133.
Some graphs admit drawings in the Euclidean plane (k-space) in such a (natural) way, that edges are represented as line segments of unit length. We say that they have the unit distance property.The influence of graph operations on the unit distance property is discussed. It is proved that the Cartesian product preserves the unit distance property in the Euclidean plane, while graph union, join, tensor product, strong product, lexicographic product and corona do not. It is proved that the Cartesian product preserves the unit distance property also in higher dimensions.  相似文献   
134.
In this paper, we study in detail, both analytically and numerically, the dynamical properties of the triangle map, a piecewise parabolic automorphism of the two-dimensional torus, for different values of the two independent parameters defining the map. The dynamics is studied numerically by means of two different symbolic encoding schemes, both relying on the fact that it maps polygons to polygons: in the first scheme we consider dynamically generated partitions made out of suitable sets of disjoint polygons, in the second we consider the standard binary partition of the torus induced by the discontinuity set. These encoding schemes are studied in detail and shown to be compatible, although not equivalent. The ergodic properties of the triangle map are then investigated in terms of the Markov transition matrices associated to the above schemes and furthermore compared to the spectral properties of the Koopman operator in L2(T2). Finally, a stochastic version of the triangle map is introduced and studied. A simple heuristic analysis of the latter yields the correct statistical and scaling behaviours of the correlation functions of the original map.  相似文献   
135.
The amounts of the 19 elements As, Br, Ca, Cd, Ce, Co, Cr, Cs, Fe, K, La, Mo, Na, Rb, Sb, Sc, Se, Sm, and Zn in 92 lyophilized autopsy human liver samples from normal subjects have been analyzed by instrumental neutron-activation analysis (INAA). For intercomparison and quality control ten samples were independently analyzed in two institutes, the Institute of High Energy Physics in China and the Joef Stefan Institute in Slovenia. Most of the element contents determined by the two institutes were in quite good agreement, even though different experimental conditions were applied, indicating the reliability of the analytical results. Analysis of the chemical species of mercury present in the ten liver samples was also performed in Slovenia. Possible differences between the element content of male and female liver samples were studied by means of Students t-test, but significant differences were found only for Ce, Co, Fe, La, Mo, and Zn. The results obtained were also compared with those reported from other areas of the world; no appreciable differences were observed. Correlation among the various elements in the human liver samples was studied using multivariate statistics. It was found that there was relatively close correlation between some elements, for example As–Fe, Ca–Fe, Cd–Co, Cd–Zn, Mo–Zn, Co–Se, Cs–Rb, Br–Rb, Sc–Sm, La–Sm, La–Ce, etc.; these correlations could be rationally explained by the similarity of the electronic structures of the elements and/or their physiological functions in the human body.  相似文献   
136.
A digestion procedure using H2SO4/HNO3/H2O2 was found to be effective for destruction of human milk samples. In conjunction with a sensitive hydride generation atomic fluorescence spectrometry detection system, it is suitable for determination of selenium in those samples where the available mass of breast milk and the low selenium concentration are limiting factors. Only 1g of milk sample is needed. The procedure is simple, rapid and of low contamination potential since it is performed in the same Teflon tube from weighing to measurement. The digestion of 20 samples is completed in three hours. The detection limit is 0.25±0.04ngg–1 of a measured solution of sample or 2.5ngg–1 of milk. The relative uncertainty is 10% (coverage factor of 2.3, 95% probability). Because of these advantages the method is particularly suitable for epidemiological studies. The mean concentration of selenium in 62 samples of human milk from lactating women residing in the North East of Italy was 12±3ngg–1, which is in the range of reference data.  相似文献   
137.
BACKGROUND: The human larynx is assumed to be a steroid receptor target organ. There are only very limited data on the evidence of steroid receptors in the vocal folds, although voice alterations due to hormonal influence and treatment have been found. GOAL OF THE STUDY: To investigate the expression of estrogen alpha, progesterone, and androgen receptors in human vocal folds (vocalis muscle, glands, lamina propria, epithelium). METHODS: Immunohistochemically, vocal fold cadaver specimens of 15 autopsied patients (6 women, 9 men), which were taken approximately 4 to 8 hours postmortem were investigated. Furthermore, one (male) vocal fold biopsy obtained intraoperatively during a laryngectomy was tested. RESULTS: No specific immunohistochemical staining for the different types of steroid hormones investigated could be observed in either the postmortem taken biopsies nor the intraoperatively one. However, several unspecific staining patterns could be observed. CONCLUSION: The results of this study contradict recently published data and question the expression of sex hormone receptors in the vocal folds. Main causes of false interpretations of unspecific staining are discussed.  相似文献   
138.
139.
The association of immunoglobulin G (IgG) glycosylation changes with various human diseases and physiological conditions is well established. Since the mechanistical explanation of the regulation of IgG glycosylation and its functional role in these various states is still missing, the eyes of the biomedical community are now turned towards animal models, which enable intervention studies necessary for conclusions on causality. Mice are recognized and used as a good experimental model for human IgG glycosylation. However, smaller blood volumes, low IgG concentrations at young ages (which are most often used in mice experiments) and multiple sampling protocols during the course of longitudinal studies would profit from a robust workflow for mouse IgG glycome analysis from minute amounts of starting material, collected through a simple sampling procedure. For this purpose, we have developed a protocol for analysis of total N-glycans of IgG isolated from mouse dried blood spots (DBS), which we report here. We show that mouse DBS are a good source of material for IgG N-glycan analysis by multiplexed capillary gel electrophoresis with laser-induced fluorescence (xCGE-LIF).  相似文献   
140.
JPC – Journal of Planar Chromatography – Modern TLC - Optimization of microwave-assisted extraction (MAE) as a method of sample preparation in thin-layer chromatographic (TLC) analysis...  相似文献   
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