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排序方式: 共有139条查询结果,搜索用时 15 毫秒
1.
Maleki Akbar Elahi Milad Assad Mamdouh El Haj Alhuyi Nazari Mohammad Safdari Shadloo Mostafa Nabipour Narjes 《Journal of Thermal Analysis and Calorimetry》2021,143(6):4261-4272
Journal of Thermal Analysis and Calorimetry - Nanofluids are attractive alternatives for the current heat transfer fluids due to their remarkably higher thermal conductivity which leads to the... 相似文献
2.
Riedl Z Kövér P Soós T Hajós G Egyed O Fábián L Messmer A 《The Journal of organic chemistry》2003,68(14):5652-5659
2-Arylsulfanyl and 2-benzylsulfanylpyridinium N-arylimides (2) easily prepared from 3-aryltetrazolopyridinium salts (1) with aryl and benzylthiolates, respectively, reacted with various dipolarophiles yielding cycloadducts that underwent transformation to give tetrahydropyrrolo[3,2-b]pyridines (5, 6, and 8) in good yields. A similar rearrangement (formation of 15) was also observed in the case of parent derivatives being unsubstituted in position 2 (12). The abscence of any significant solvent effect, comparison of the sulfur and non-sulfur analogues, as well as the stereoselective nature of the observed ring transformation seem to support a sigmatropic mechanism. Structure elucidation of the products has been carried out by single-crystal X-ray diffraction and (1)H NMR experiments. 相似文献
3.
Mohammad Abul‐Haj Miguel Quirs Juan M. Salas 《Acta Crystallographica. Section C, Structural Chemistry》2000,56(8):934-935
The title compound, [Ni(NCS)2(C5H4N4O)2(H2O)2], crystallizes in the triclinic space group P. The molecular unit contains two neutral molecules of 4,5‐dihydro‐1,2,4‐triazolo[1,5‐a]pyrimidin‐5‐one (5HtpO) coordinated through the N atom in position 3, two thiocyanate ligands coordinated through their N atoms and two water molecules completing an octahedral environment around the NiII ion, which lies on a centre of inversion. The structure is stabilized by hydrogen bonding. Distances in the coordination sphere are Ni—N3(5HtpO) 2.132 (2), Ni—O(water) 2.085 (2) and Ni—N(thiocyanato) 2.040 (2) Å. 相似文献
4.
J. Poustka K. Holadová J. HajšLová 《International journal of environmental analytical chemistry》2013,93(2-4):139-144
Abstract Application of supercritical fluid extraction (SFE) utilizing pure carbon dioxide for selective isolation of organophosphates from contaminated cereals has been tested. At the beginning of the experiments the extractability of added standards from an empty extraction vessel (thimble) and from various materials such as filter paper, sand, Celite and anhydrous sodium sulfate was tested to estimate the behavior of organophosphates. Further method development was carried out using a spiked sample of flour, which was analyzed within the proficiency testing for organophosphorus pesticides analysis (round 7) organized by Food Analysis Performance Assessment Scheme (FAPAS, MAFF-UK). Comparison of the SFE method with a classical method currently employed for sample preparation (i.e. extraction with acetone/methanol mixture followed by gel permeation chromatographic clean up) showed advantages of the SFE technique such as simplification of the sample preparation step and thereby significant speeding up of the determination of organophosphates in cereals. 相似文献
5.
J. Hajšlová R. Schoula K. Holadová J. Poustka 《International journal of environmental analytical chemistry》2013,93(2-4):163-173
Abstract The suitability of three GC-ECD systems for the separation of a model mixture containing various congeners of PCBs together with persistent chlorinated aromatics (pesticides and their metabolites, industrial chemicals) was tested. Analyses were performed on two parallel capillaries, the stationary phase of one of them was always in routine practice very common 5% phenyl-methylpolysiloxane, the second one was either 50% phenylmethylpolysiloxane or 7% phenyl-7% cyanopropyl-methylpolysiloxane. The number of unresolved (coeluted) analytes was significantly reduced in these systems and thus unbiased quantitation of PCBs and other components used for regulation was possible. The utilization of this type of multidimensional chromatography for rapid and reliable analysis of real samples (fish oil, human fat) was documented. 相似文献
6.
Ersan Ronak Haj Alagoz Mehmet Abdullah Ertan-Bolelli Tugba Duran Nizami Burmaoglu Serdar Algul Oztekin 《Molecular diversity》2021,25(4):2247-2259
Molecular Diversity - In the present work, a series of bisbenzazole derivatives were designed and synthesized as antiproliferative agents. The antiproliferative activity of these compounds was... 相似文献
7.
Kornelia Indykiewicz Marcin Hajłasz Bogdan Paszkiewicz 《Central European Journal of Physics》2013,11(2):219-225
This paper presents the methods of fabricating narrow parallel submicrometric stripes in silicon dioxide and a resist layer. The experiments were conducted by two techniques: double patterning lithography and double exposure lithography. In addition to the above mentioned processes, mask translation was applied. For all conducted experiments, chrome masks and a 405 nm line of the high pressure mercury lamp of an MA-56 Mask Aligner System were used. The main aim of the performed tests was to establish the utility and the possible applications of the methods used. 相似文献
8.
9.
Ghalandari Mohammad Irandoost Shahrestani Misagh Maleki Akbar Safdari Shadloo Mostafa El Haj Assad Mamdouh 《Journal of Thermal Analysis and Calorimetry》2021,145(4):1837-1848
Journal of Thermal Analysis and Calorimetry - Heat exchangers are applicable in different industries and technologies, and their performance is influenced by different parameters. In addition to... 相似文献