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11.
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Molecular Diversity - The theoretical calculations, namely multipole-derived charge analysis, quantum theory of atom in molecules, and non-bonding interaction (NCI), were performed for...  相似文献   
13.
The synthesis of N-[2-(heteroarylhydrazono)ethyl]benz-amides starting from (Z)-2-benzoylamino-3-chloro-2-propenoic acid and heteroarylhydrazines is reported.  相似文献   
14.
The recent introduction of polymerase chain reaction (PCR)-massively parallel sequencing (MPS) technologies in forensics has changed the approach to allelic short tandem repeat (STR) typing because sequencing cloned PCR fragments enables alleles with identical molecular weights to be distinguished based on their nucleotide sequences. Therefore, because PCR fidelity mainly depends on template integrity, new technical issues could arise in the interpretation of the results obtained from the degraded samples. In this work, a set of DNA samples degraded in vitro was used to investigate whether PCR-MPS could generate “isometric drop-ins” (IDIs; i.e., molecular products having the same length as the original allele but with a different nucleotide sequence within the repeated units). The Precision ID GlobalFiler NGS STR panel kit was used to analyze 0.5 and 1 ng of mock samples in duplicate tests (for a total of 16 PCR-MPS analyses). As expected, several well-known PCR artifacts (such as allelic dropout, stutters above the threshold) were scored; 95 IDIs with an average occurrence of 5.9 IDIs per test (min: 1, max: 11) were scored as well. In total, IDIs represented one of the most frequent artifacts. The coverage of these IDIs reached up to 981 reads (median: 239 reads), and the ratios with the coverage of the original allele ranged from 0.069 to 7.285 (median: 0.221). In addition, approximately 5.2% of the IDIs showed coverage higher than that of the original allele. Molecular analysis of these artifacts showed that they were generated in 96.8% of cases through a single nucleotide change event, with the C > T transition being the most frequent (85.7%). Thus, in a forensic evaluation of evidence, IDIs may represent an actual issue, particularly when DNA mixtures need to be interpreted because they could mislead the operator regarding the number of contributors. Overall, the molecular features of the IDIs described in this work, as well as the performance of duplicate tests, may be useful tools for managing this new class of artifacts otherwise not detected by capillary electrophoresis technology.  相似文献   
15.
Porous polypropylene membranes were coated with plasma polymerized titanium isopropoxide in a 75 kHz plasma reactor. It was noted that the presence of air in the plasma chamber increased the amount of deposited polymer. Selection of the process parameters enabled obtaining membranes with up to 300 εg cm?2 of polymerized titanium isopropoxide. Deposition of the titanium oxide layer resulted in the reduction of permeate flux but it significantly improved the membrane photocleaning ability. The recovery index reached the level of 95 % for membranes with the highest amount of the titanium oxide deposit.  相似文献   
16.
Predicting solute adsorption on activated carbon: phenol   总被引:2,自引:0,他引:2  
Activated carbon (AC), the most widely used adsorbent in water and in wastewater treatment, comprises a high surface area of very small, convoluted and interconnected pores. Despite the wide use of AC, there is little fundamental atomic-level understanding of its adsorption capacity and selectivity as well as its pore structure. The purpose of this work is to suggest the methodology for calculation of equilibrium adsorption capacity of common water organic pollutants and use it for phenol as a model. The effects of various functional groups, pore size, and coverage on thermodynamics of phenol adsorption from the gas phase and from water media are calculated using molecular mechanics (MM) and density functional theory (DFT) approaches.  相似文献   
17.
An infrared spectroscopic study of the composition of these complexes in the solid state is described. Evaluation of the spectra made it possible to distinguish changes in the character of the lanthanide—ligand bonds in the series La — Lu, and to study the “double-double” effect.  相似文献   
18.
A simple and efficient protocol is utilized for the synthesis of novel functionalized benzobicyclo[3.2.1]octadiene derivatives by photocatalytic oxygenation of a furan derivative using an anionic free-base porphyrin as well as cationic and anionic manganese(III) porphyrins under different reaction conditions. The course and yields of these reactions were compared to those of the thermal reaction using m-chloroperbenzoic acid as the oxidizing agent. The deviating reaction pathways with anionic and cationic metalloporphyrins may be attributed to simultaneous electronic and steric effects. Application of free-base and metalated water-soluble porphyrins for photocatalytic oxygenation of the furan ring fused to the rigid methano-bridged skeleton proved to be regioselective and flexible compared to the thermal reactions with mCPBA, giving at the same time novel potentially biologically active bicyclo[3.2.1]octenes with the basic skeleton of which is incorporated in many natural compounds.  相似文献   
19.
Zusammenfassung Basisches Magnesiumcarbonat und basisches Zinkcarbonat erlangen nach Tieftemperaturbehandlung mit flüssiger Luft eine bedeutend größere Oberfläche, die auch bei den betr. oxidischen Abkömmlingen nach ihrer thermischen Beanspruchung bei 800° bestehen bleibt. Ebenfalls tieftemperatur-empfindlich ist das dunkelbraune röntgenamorphe Eisen(III)-hydroxid (Orthohydroxid), während das topochemische röntgenamorphe und ziegelfarbige Eisen(III)-hydroxid (Iso-Orthohydroxid) sowie ein daraus gewonnenes hellgelbes -FeOOH, die schon von sich aus oberflächengroß sind, sich in dieser Hinsicht als indifferent erwiesen. Die aus den verschiedenen Eisen(III)-hydroxiden bei 800° gewonnenen -Oxide hatten eine sehr differente scheinbare Dichte bzw. Oberfläche.  相似文献   
20.
Cellulose - Bookkeeper, the most widely used deacidification process based on MgO particles, was systematically evaluated on two sets of nonvaluable historical paper samples. Established analytical...  相似文献   
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