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排序方式: 共有113条查询结果,搜索用时 15 毫秒
1.
I. Ciocazanu F. Dumitrascu V. Meltzer 《Journal of Thermal Analysis and Calorimetry》1998,51(2):595-599
The following acetylated derivatives of indazole: 3-indazolone, l-acetyl-3-indazolone, 2-acetyl-3-indazolone, l,2-diacetyl-3-indazolone and 3-acetoxy-l-acetyl-indazole were studied by combustion calorimetry. The enthalpies of formation were calculated from enthalpies of combustion. The isomeri-sation enthalpies were also calculated. The phase transition temperatures as well as caloric capacities of the studied compound in the crystalline phase were determined by DSC. 相似文献
2.
Rusu G. B. Topala I. Borcia C. Dumitrascu N. Borcia G. 《Plasma Chemistry and Plasma Processing》2016,36(1):341-354
Plasma Chemistry and Plasma Processing - A study is conducted on the surface modification of synthetic woven textiles, using atmospheric-pressure plasma, for controlled adhesion for subsequent... 相似文献
3.
Viorel Cîrcu Doina Mănăilă-Maximean Constantin Roşu Monica Iliş Yann Molard Florea Dumitraşcu 《Liquid crystals》2013,40(2):123-132
A series of ortho-metallated Pd and Pt complexes containing an imine ligand carrying three alkoxy chains and N-benzoylthiourea derivatives as co-ligands were prepared and their liquid crystalline properties investigated. Their structures were assigned based on elemental analysis, IR and 1H NMR spectroscopy, whereas thermal properties were investigated by differential scanning calotimetry and polarising optical microscopy. All the compounds exhibit monotropic transitions involving nematic and smectic A phases, with the mesomorphic behaviour strongly related to the type of N-benzoylthiourea as well as the metal centre used. The thermally stimulated depolarisation current technique was employed to determine the conduction mechanism, phase transition temperature and the activation energies for one of the ortho-metallated Pd complexes. 相似文献
4.
Mihaela Tertis Oana Hosu Bogdan Feier Andreea Cernat Anca Florea Cecilia Cristea 《Molecules (Basel, Switzerland)》2021,26(11)
Food safety and quality control pose serious issues to food industry and public health domains, in general, with direct effects on consumers. Any physical, chemical, or biological unexpected or unidentified food constituent may exhibit harmful effects on people and animals from mild to severe reactions. According to the World Health Organization (WHO), unsafe foodstuffs are especially dangerous for infants, young children, elderly, and chronic patients. It is imperative to continuously develop new technologies to detect foodborne pathogens and contaminants in order to aid the strengthening of healthcare and economic systems. In recent years, peptide-based sensors gained much attention in the field of food research as an alternative to immuno-, apta-, or DNA-based sensors. This review presents an overview of the electrochemical biosensors using peptides as molecular bio-recognition elements published mainly in the last decade, highlighting their possible application for rapid, non-destructive, and in situ analysis of food samples. Comparison with peptide-based optical and piezoelectrical sensors in terms of analytical performance is presented. Methods of foodstuffs pretreatment are also discussed. 相似文献
5.
Denisa Dumitrescu Sergiu Shova Constantin Draghici Marcel Mirel Popa Florea Dumitrascu 《Molecules (Basel, Switzerland)》2021,26(12)
3-Arylsydnones bearing fluorine and bromine atoms on the benzene ring were synthesized from N-nitroso-2-fluorophenylglycines and characterized by NMR spectroscopy. These were employed further in synthesis of the corresponding 1-(2-fluorophenyl)pyrazoles by 1,3-dipolar cycloaddition reaction with dimethyl acetylenedicarboxylate (DMAD) as activated dipolarophile. The sydnones as reaction intermediates were characterized by single crystal X-ray diffraction analysis showing interesting features such as halogen bonding as an important interaction in modeling the crystal structure. 相似文献
6.
Mihai Răducă Cristian D. Ene Sorana Ionescu Mihaela Florea 《Journal of Coordination Chemistry》2019,72(8):1222-1237
Abstract1-D coordination polymers, 1∞[Zn(fl)2]·2EtOH and 1∞[Zn(fl)2]·2MeOH, and a dinuclear complex, [{Zn(fl)2}2(dienpip)]·4H2O·4EtOH (dienpip?= N,N′-bis(2-aminoethyl)piperazine), were obtained using Zn(II) ions and fluorescein anions (fl). Thermal analysis shows stability of the polymers after solvent removal up to more than 400?°C. Crystallization solvent molecules were removed under reduced pressure with the preservation of the polymeric structure, 1∞[Zn(fl)2]. Desolvated crystals were exposed to I2 vapors and the crystal structure determination by X-ray diffraction confirmed the presence of I2 molecules in the channels generated in crystals by the metal-organic framework. The iodine content, evaluated by X-ray diffraction, corresponds to the overall formula 1∞[Zn(fl)2]·0.3I2. The optical properties of the coordination polymers and the dinuclear complex have been investigated. 相似文献
7.
Three new mesoionic oxazolo[3,2-b]pyridazin-2-one derivatives, in different solutions have been investigated by UV-Vis absorption, steady-state and time-resolved fluorescence methods. The effect of substituents on the extension of conjugation of the pi-electrons from mesoionic oxazolone has been evidenced by bathochromic shifts of the absorption and fluorescence maxima positions. The fluorescence decay data could be fitted to single-exponential or double-exponential function. The lifetime values are much higher in aprotic polar solvents and in the case of the derivatives that present an extension of the conjugation of pi-electrons. The properties of the compounds present a solvent dependence, being tested in micellar solutions as potential molecular probe "sensitive" to the environment polarity. 相似文献
8.
In the present paper we want to develop an analytical model to study the thermal behavior of multi-layered solid media in interaction with a laser beam. We suppose that each layer has a constant thermal conductivity. We consider that the laser beam is formed by decoupled [Phys Rev A 1996; 53: 4435] multi-modes Hermite–Gauss beams. The model is applied using the classical heat equation which was solved using the integral transform method [Infrared Phys Technol 2002; 42: 31; Optics Laser Technol 2004; 36: 219–22; Optics Laser Technol 2004; 36: 677–9; Proc SPIE 2003; 5227: 323]. 相似文献
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