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排序方式: 共有255条查询结果,搜索用时 15 毫秒
1.
Prof. Andrea Baier Dr. Anne Kokel Dr. William Horton Ewa Gizińska Dr. Garima Pandey Prof. Ryszard Szyszka Prof. Béla Török Prof. Marianna Török 《ChemMedChem》2021,16(12):1927-1932
A set of novel hydrazone derivatives were synthesized and analyzed for their biological activities. The compounds were tested for their inhibitory effect on the phosphorylating activity of the protein kinase CK2, and their antioxidant activity was also determined in three commonly used assays. The hydrazones were evaluated for their radical scavenging against the DPPH, ABTS and peroxyl radicals. Several compounds have been identified as good antioxidants as well as potent protein kinase CK2 inhibitors. Most hydrazones containing a 4-N(CH3)2 residue or perfluorinated phenyl rings showed high activity in the radical-scavenging assays and possess nanomolar IC50 values in the kinase assays. 相似文献
2.
H. Baier 《Structural and Multidisciplinary Optimization》1994,7(3):184-190
Structural optimization problems may be ill-posed or weakly conditioned. Different causes of such ill-conditioning are investigated, which can arise, for example, from the problem statement itself and its probable strong nonconvexity, or the interaction of the optimization algorithm with the discretized physical model. These effects could cause undesirable or incorrect solutions or no meaningful solutions at all. Thus ill-posed or ill-conditioned problems must be treated and assessed carefully. Some approaches to dealing with such problems and possible consequences for the optimal designs are discussed. 相似文献
3.
A unified theoretical method for the calculation of the radio capacity of multiple-access schemes such as FDMA (frequency-division multiple access), TDMA (time-division multiple access), CDMA (code-division multiple access) and SSMA (spread-spectrum multiple access) in noncellular and cellular mobile radio systems is presented for AWGN (additive white Gaussian noise) channels. The theoretical equivalence of all the considered multiple-access schemes is found. In a fading multipath environment, which is typical for mobile radio applications, there are significant differences between these multiple-access schemes. These differences are discussed in an illustrative manner revealing several advantages of CDMA and SSMA over FDMA and TDMA. Novel transmission and reception schemes called coherent multiple transmission and coherent multiple reception are briefly presented 相似文献
4.
In Europe, the challenge of the design of third-generation cellular mobile radio systems has been taken numerous research and development activities in this field have been started. The authors try to give an overview of the European activities in this field. The article is organized in two parts. In the first part, the requirements for third-generation cellular mobile radio systems such as Universal Mobile Telecommunications System (UMTS) and Future Public Land Mobile Telecommunications System (FPLMTS), which has been named International Mobile Telecommunications after the year 2000 (IMT-2000) are presented concisely. Also, the importance and challenge of the multiple access design for such third-generation cellular mobile radio systems is explained. In the second part, numerous European research activities with focus on the multiple access design for third-generation cellular mobile radio systems are reviewed 相似文献
5.
Optimum spread spectrum signals for wideband channel sounding 总被引:1,自引:0,他引:1
Optimum periodic spread spectrum test signals suitable for wideband channel sounding are introduced. In contrast to conventional test signals based on m sequences, the proposed test signals with complex lowpass equivalents offer minimum crest factors in order to minimise the outband power spectral density at the output of a nonlinear transmitter amplifier.<> 相似文献
6.
Jantsch Simon Müller David Baier Christel Klein Joachim 《Formal Methods in System Design》2021,58(1-2):42-82
Formal Methods in System Design - Due to the high complexity of translating linear temporal logic (LTL) to deterministic automata, several forms of “restricted” nondeterminism have been... 相似文献
7.
8.
For the first time in the Federal Republic of Germany Yersinia species "frederiksenii", "kristensenii", "serovar 0 : 6" (each once) and "serovar 0 : 5" (twice) were found in the stool of 5 patients with gastroenteritic complaints. Serum agglutinins against these species could not be demonstrated. Other enteropathogenic microorganisms were excluded microscopically, by culture and serologically. These Yersinia isolates were resistant against penicillin G, ampicillin, carbenicillin, ticarcillin, and cefalotin. 相似文献
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10.
Jiri Hajek Tomas Jurena Bernhard Baier Arash Bagherzadeh Tom Schnick Quido Smejkal 《化学,工程师,技术》2015,87(7):991-997
Calcination of diatomite is an expensive process frequently resulting in products with unpredictable structure. Alternatively, calcination in swirling flow is an energy‐saving option. Computational fluid dynamics modeling of an experimental calcination process unit is presented. Experimental results and systematic collection of process data were used to define boundary condition for steady‐state and transient simulation runs. The comparison of experimental and simulation results shows the complexity of the calcination process. The results can be used for further process optimization. 相似文献