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排序方式: 共有404条查询结果,搜索用时 0 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.
6.
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
7.
Information Visualization Within a Digital Video Library 总被引:1,自引:0,他引:1
The Informedia Digital Video Library contains over a thousand hours of video, consuming over a terabyte of disk space. This paper summarizes the multimedia abstractions used to represent this video in prior systems and introduces the visualization techniques employed to browse and navigate multiple video documents at once. 相似文献
8.
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
9.
Jesús F. Ontiveros Bing Hong Kenji Aramaki Christel Pierlot Jean-Marie Aubry Véronique Nardello-Rataj 《Journal of surfactants and detergents》2021,24(3):401-410
A series of symmetrical dialkyl methanesulfonate amphiphiles [DiC n CHSO 3 ] m M (n = 6, 7, 8) with different counter cations (Mm+ = H+, Li+, Na+, K+, Cu2+, Zn2+, Mg2+, Ca2+, Sc3+) were synthesized in five steps. Their solubility and critical micelle concentration (CMC) in water were determined highlighting a huge effect of the chain length and the nature of the cation. The hydrophilic–lipophilic balance of the surfactants were assessed with the phase inversion temperature (PIT)-slope method based on the deviation from the PIT of the reference C10E4/n-octane/0.01 M NaCl(aq) emulsion through addition of increasing amounts of the dialkyl methanesulfonates. The hydrophilicity of the surfactants was thus ranked in terms of dPIT/dxsulfonate. A “cation” scan with the [DiC 6 CHSO 3 ] m M /benzene/water systems at fw = 0.5 was finally performed confirming the hydrophilicity ranking obtained with the PIT-slope method. It revealed that the [DiC 6 CHSO 3 ] 2 Mg behaves as a “Balanced Surfactant” able to form spontaneously a three-phase microemulsion system (Winsor III) just in the presence of water and oil, in the same way as the catalytic surfactant dimethyldioctylammonium molybdate, which has the same PIT-slope. 相似文献
10.
Ethylene/propylene (E/P) and ethylene/1-octene (E/O) copolymers were polymerized with two bridged metallocene catalyst systems, Et(Ind)2ZrCl2/MAO and Et(Ind)2HfCl2/MAO, respectively. The copolymers produced and some commercial reference copolymers were characterized by DSC, SEC, DMA and 13C NMR. The Hf-catalysed E/P polymerizations showed much lower activities than the corresponding Zr-catalysed polymerizations but gave polymers with high molar mass. The Hf-based copolymers also showed two melting peaks which may be indicative of several active sites of the catalyst. A comparison of E/P copolymers, containing about 20 mol-% propylene and produced with Zr, Hf and homogeneous V-catalysts, respectively, indicated that the Hf and V-catalysts gave material more similar to each other. The E/O copolymers produced with Zr-catalysts gave very low molar masses and the reactivity ratios, calculated from the NMR data, indicated that the Hf-catalyst has a slightly higher reactivity for 1-octene and the Zr-catalyst some better reactivity for ethylene. Segregation fractionation studies by DSC indicated that a lower 1-octene feed gives more heterogeneous copolymers and the DMA measurements reveal the existence of a linear correlation between the 1-octene content and the intensity of the tan δmax peak. 相似文献