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51.
α-Substituted Phosphonates. 39. Methane-diphosphonic Esters by U.V.-Induced Michaelis-Becker-Reaction Dibromomethane resp. chlorbromomethane reacts with sodium dialkyl phosphite in heptane-/liq.NH3 or in liq. NH3 by u.v. irradiation at low temperatures to give in good yields methane diphosphonic acid tetraalkylesters 1 . In the same manner with sodium diethyl thionophosphite the corresponding methane-bis-thiophosphonic acid tetraethylester 4 is obtained.  相似文献   
52.
The development of a fast and accurate intraoperative method that enables the differentiation and stratification of cancerous lesions is still a challenging problem in laboratory medicine. Therefore, it is important to find and optimize a simple and effective analytical method of enabling the selection of distinctive metabolites. This study aims to assess the usefulness of solid-phase microextraction (SPME) probes as a sampling method for the lipidomic analysis of brain tumors. To this end, SPME was applied to sample brain tumors immediately after excision, followed by lipidomic analysis via liquid chromatography-high resolution mass spectrometry (LC-HRMS). The results showed that long fibers were a good option for extracting analytes from an entire lesion to obtain an average lipidomic profile. Moreover, significant differences between tumors of different histological origin were observed. In-depth investigation of the glioma samples revealed that malignancy grade and isocitrate dehydrogenase (IDH) mutation status impact the lipidomic composition of the tumor, whereas 1p/19q co-deletion did not appear to alter the lipid profile. This first on-site lipidomic analysis of intact tumors proved that chemical biopsy with SPME is a promising tool for the simple and fast extraction of lipid markers in neurooncology.  相似文献   
53.
On the Phoshoric Acid in Potato Starch. Potato starch contains chemically linked ortho-phosphoric acid (30 to 175 mg% P). Among the physico-chemical properties of potato starch effected by the phosphoric acid the most important are ion exchange and selfhydrolysis. By the ability of ion exchange it is possible to produce the salts of the pure esters of amylo-phosphoric acid (cationic starches). Sodium, potassium, ammonium, calcium and magnesium starches differ in rheological properties. The hydrogen ions of amylophosphoric acid are able to effect the hydrolytic splitting of the starch. This hydrolysis consists of two different processes: the splitting of the glucosidic linkages and the splitting of the ester linkage between the phosphoric acid and the glucose unit. Velocity of self-hydrolysis is dependent on the hydrogen ion concentration. The self-hydrolysis of hydrogen starch offers the possibility of producing degraded starch products with different technical properties without any addition of chemicals and/or enzymes.  相似文献   
54.
Carbon-encapsulated magnetic nanoparticles (CEMNPs) are studied as mobile sorbents for removal of heavy metal ions (Cu2+, Co2+, Cd2+) from aqueous solutions. The ion uptakes achieve 95% for cadmium and copper. CEMNPs-based sorbents also have excellent adsorption capacities (between 1.23 and 3.21 mg/g), which are considerably higher than the capacities of activated carbons (between 0.37 and 0.39 mg/g).  相似文献   
55.
The reactive oxirane groups were incorporated into the macromolecule as substituents in the side chains of loosely‐grafted copolymer or in the arms of star‐shaped copolymer using glycidyl methacrylate (GMA) in the controlled atom transfer radical polymerization (ATRP). The branched GMA copolymers with various architectures were obtained by using hydrophobic copolymers containing six and seven units of caprolactone 2‐(methacryloyloxy)ethyl ester (CLMA) functionalized with bromoester groups, and trifunctional poly(ε‐caprolactone) (PCL), as well as hydrophilic tri‐, and six‐functional acetal derivatives of D ‐glucopyranosides as (macro)initiators with biodegradable and biocompatible properties. The well‐defined copolymers with core‐shell structures and polymerization degrees of GMA in the range of 20–100 per side chain/arm at 20–70% of monomer conversion within 1–6 h and narrow molecular weight distributions (Mw/Mn = 1.14–1.4) were obtained. POLYM. ENG. SCI., 2013. © 2012 Society of Plastics Engineers  相似文献   
56.
Pectobacterium parmentieri is a pectinolytic plant pathogenic bacterium causing high economic losses of cultivated plants. The highly devastating potential of this phytopathogen results from the efficient production of plant cell wall-degrading enzymes, i.e., pectinases, cellulases and proteases, in addition to the impact of accessory virulence factors such as motility, siderophores, biofilm and lipopolysaccharide (LPS). LPS belongs to pathogen-associated molecular patterns (PAMPs) and plays an important role in plant colonization and interaction with the defense systems of the host. Therefore, we decided to investigate the heterogeneity of O-polysaccharides (OPS) of LPS of different strains of P. parmentieri, in search of an association between the selected genomic and phenotypic features of the strains that share an identical structure of the OPS molecule. In the current study, OPS were isolated from the LPS of two P. parmentieri strains obtained either in Finland in the 1980s (SCC3193) or in Poland in 2013 (IFB5432). The purified polysaccharides were analyzed by utilizing 1D and 2D NMR spectroscopy (1H, DQF-COSY, TOCSY, ROESY, HSQC, HSQC-TOCSY and HMBC) in addition to chemical methods. Sugar and methylation analyses of native polysaccharides, absolute configuration assignment of constituent monosaccharides and NMR spectroscopy data revealed that these two P. parmentieri strains isolated in different countries possess the same structure of OPS with a very rare residue of 5,7-diamino-3,5,7,9-tetradeoxy-l-glycero-l-manno-non-2-ulosonic acid (pseudaminic acid) substituted in the position C-8: 3)-β-d-Galf-(13)-α-d-Galp-(18)-β-Pse4Ac5Ac7Ac-(26)-α-d-Glcp-(16)-β-d-Glcp-(1. The previous study indicated that three other P. parmentieri strains, namely IFB5427, IFB5408 and IFB5443, exhibit a different OPS molecule than SCC3193 and IFB5432. The conducted biodiversity-oriented assays revealed that the P. parmentieri IFB5427 and IFB5408 strains possessing the same OPS structure yielded the highest genome-wide similarity, according to average nucleotide identity analyses, in addition to the greatest ability to macerate chicory tissue among the studied P. parmentieri strains. The current research demonstrated a novel OPS structure, characteristic of at least two P. parmentieri strains (SCC3193 and IFB5432), and discussed the observed heterogenicity in the OPS of P. parmentieri in a broad genomic and phenotype-related context.  相似文献   
57.
Comparative results of explosive decomposition equation and explosion parameter calculations of several high explosives are described. Calculations were carried out by two different algorithms. Results of calculations are compared with literature data. Some corrections of simple Kamlet's formulae for detonation parameter calculations are proposed adjusting the formulae to calculated explosion parameters.  相似文献   
58.
59.
Multidimensional Systems and Signal Processing - The paper is a comprehensive study on classification of motion capture data on the basis of dynamic time warping (DTW) transform. It presents both...  相似文献   
60.
The aim of this study was to assess the effects of myocardium organic damage on time-domain parameters of atrial signal-averaged ECG (ASAECG) in patients with electrically induced paroxysmal atrial fibrillation (PAF). The investigation was done in 120 patients with subjective symptoms of cardiac rhythm disorders suggesting atrial fibrillation and for further analysis were selected 51 patients in whom atrial PAF was induced during transoesophageal pacing (TEP). Patients were divided according to organic damage of myocardium-38 pts (24 male and 14 female, mean age 52.1 +/- 11.6-group I) and without-13 pts (9 male and 4 female, mean age 35.4 +/- 9.9 -group II). In all two dimensional echocardiographic examination, 24-hours Holter monitoring, exercise testing and TEP were made. Recording of ASAECG was done with a commercially available system HIPEC-200 HA Aerotel. The following time-domain parameters of ASAECG were calculated: the root mean square voltage of the terminal 10, 20, 30 ms of the filtered P-wave (RMS 10, 20, 30) and time duration of filtered P-wave (PWD) and also time duration of P-wave from Frank's leads X, Y, Z (XP, YP, ZP). Atrial late potentials (ALP) were defined as the presence of two parameters: RMS 10 < 4 microV and PWD > 123 ms. If we compared time-domain parameters of ASAECG between examined groups it occurred that only the values of PWD attained statistically significant differences, respectively 123.3 +/- 15.4 ms vs 115 +/- 11.2 ms, p < 0.05. In 14 (36.8%) patients from first group and in 2 (15.4%) patients from second ALP were confirmed. We concluded that presence of myocardium organic damage have essentially influenced on time duration of filtered P-wave.  相似文献   
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