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排序方式: 共有367条查询结果,搜索用时 14 毫秒
1.
Akai Takashi Alhammadi Amer M. Blunt Martin J. Bijeljic Branko 《Transport in Porous Media》2019,130(3):731-749
Transport in Porous Media - We demonstrate how to use numerical simulation models directly on micro-CT images to understand the impact of several enhanced oil recovery (EOR) methods on microscopic... 相似文献
2.
Construction of a New Class of Tetracycline Lead Structures with Potent Antibacterial Activity through Biosynthetic Engineering 下载免费PDF全文
Dr. Urška Lešnik Dr. Tadeja Lukežič Dr. Ajda Podgoršek Dr. Jaka Horvat Dr. Tomaž Polak Dr. Martin Šala Branko Jenko Dr. Kirsten Harmrolfs Dr. Alain Ocampo‐Sosa Prof. Dr. Luis Martínez‐Martínez Dr. Paul R. Herron Dr. Štefan Fujs Dr. Gregor Kosec Prof. Dr. Iain S. Hunter Prof. Dr. Rolf Müller Prof. Dr. Hrvoje Petković 《Angewandte Chemie (International ed. in English)》2015,54(13):3937-3940
Antimicrobial resistance and the shortage of novel antibiotics have led to an urgent need for new antibacterial drug leads. Several existing natural product scaffolds (including chelocardins) have not been developed because their suboptimal pharmacological properties could not be addressed at the time. It is demonstrated here that reviving such compounds through the application of biosynthetic engineering can deliver novel drug candidates. Through a rational approach, the carboxamido moiety of tetracyclines (an important structural feature for their bioactivity) was introduced into the chelocardins, which are atypical tetracyclines with an unknown mode of action. A broad‐spectrum antibiotic lead was generated with significantly improved activity, including against all Gram‐negative pathogens of the ESKAPE panel. Since the lead structure is also amenable to further chemical modification, it is a platform for further development through medicinal chemistry and genetic engineering. 相似文献
3.
The methylation of some pyrazolin-5-ones with dimethyl sulfate in different reaction conditions is described, ft is found that it is possible achived selective introducing of methyl group in desired position of pyrazolin-5-one ring which is of great interest for preparation of many analgesics and antipyretics with pyrazolin-5-one unit. 相似文献
4.
Steva Lević Nina Obradović Vladimir Pavlović Bojana Isailović Ivana Kostić Miodrag Mitrić Branko Bugarski Viktor Nedović 《Journal of Thermal Analysis and Calorimetry》2014,118(2):661-668
In this study, polyvinyl alcohol (PVA) nanofibers with ethyl vanillin as an active compound were prepared using electrospinning technique. The final products of electrospinning process were in the form of nanofibers films. PVA/ethyl vanillin nanofibers, having fibers diameters in the range 100–1700 nm, were successfully electrospun from ethanol/water mixture of PVA and ethyl vanillin. The effects of immobilization process on ethyl vanillin thermal properties were investigated by differential scanning calorimetry (DSC). The results of DSC showed significant influence of immobilization process on thermal properties of ethyl vanillin. It was noticed that melting point of immobilized ethyl vanillin was lower (~55 °C) compared to free flavor (~77 °C). Our results showed that films based on PVA/ethyl vanillin nanofibers are mechanically stable. 相似文献
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Branko Sarić 《Czechoslovak Mathematical Journal》2011,61(4):1017-1022
In this paper a full totalization is presented of the Kurzweil-Henstock integral in the multidimensional space. A residual function of the total Kurzweil-Henstock primitive is defined. 相似文献
9.
Branko Drlja?aSvetislav Savovi? Alexandar Djordjevich 《Optics and Lasers in Engineering》2011,49(5):618-622
The time-dependent power flow equation, which is reduced to its time-independent counterpart is employed to calculate frequency response and bandwidth in addition to mode coupling and mode-dependent attenuation in a step-index plastic optical fiber. The frequency response is specified as a function of distance from the input fiber end. This is compared to reported measurements. Mode-dependent attenuation and mode dispersion and coupling are known to be strong in plastic optical fibers, leading to major implications for their frequency response in data transmission systems. 相似文献
10.
A simple synthetic procedure for direct formamidation and amination of aryl halides mediated by copper(II) salts was developed in open air, without an external ligand in formamide with potassium carbonate as a base. This approach is particularly efficient when electron active aryl halides are used as substrates. In these cases almost quantitative formamidation was observed. 相似文献