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991.
An indirect laser-induced method for selective removal of large copper areas from a printed circuit board is theoretically and experimentally investigated. The results show that the threshold condition for the process involves phase transition of the epoxy-based substrate resin. Optimal parameters for maximizing process speed are found and discussed. 相似文献
992.
993.
In Charikar et al. (J. Comput. Syst. Sci. 64(4):785–819, 2002) the authors proposed a new model for studying the function evaluation problem based on a variant of the classical decision
tree problem for Boolean functions. In this variant each variable of the function to evaluate has an associated cost which
has to be paid in order to read the value of the variable. Given a function f and an assignment σ to the variables of f, the performance of an algorithm for evaluating f is measured via the competitive ratio, i.e., the ratio of the total cost spent by the algorithm and the cost of the cheapest
set of variables constituting a certificate for the value of the function on the given assignment. 相似文献
994.
We obtain nonuniform estimates depending on the interval length for Poisson and compound Poisson approximations to 2-runs.
We calculate exact constants for the estimates in the Wasserstein metric. 相似文献
995.
Gorazd Hribar Andrej Žnidaršič Marjan Bele Uroš Maver Simon Caserman Miran Gaberšček Vladka Gaberc-Porekar 《Journal of nanoparticle research》2011,13(7):3019-3032
The authors’ intention was to prepare nanometer-sized zinc-phosphate nanoparticles that would be capable of binding histidine-rich
TNF-α analogs onto their surface via a coordinative bond. Zinc-phosphate nanoparticles with a size of around 60 nm were prepared
by a wet precipitation method and characterized using SEM, EDX, XRD, and DLS. First, BSA was bound as a testing protein, afterward
two TNF-α analogs with decreased activity were bound to the described nanoparticles. The efficiency of binding and the existence
of coordinative bond were confirmed with SDS-PAGE analysis. During binding, particle storage, and release experiments, the
prepared TNF-α analogs retained their biological activity—hence the epitopes necessary for formation of antibodies stayed
intact. The particle size did not change within a period of 2 weeks. No significant agglomeration was observed, the particles
could be quickly dispersed in ultrasound. The present nanoparticles and the general approach of coordinative binding are widely
applicable for natural and engineered histidine-rich proteins. The nanoparticles bearing appropriate TNF-α analogs could also
be potentially used for active immunotherapy to tackle the chronic inflammatory diseases associated with pathogenically elevated
levels of TNF-α. 相似文献
996.
Borko D. Stoši? 《Physica A》2009,388(12):2373-2382
In this work an application of MCMC is proposed for unsupervised data classification, in conjunction with a novel pairwise objective function, which is shown to work well in situations where clusters to be identified have a strong overlap, and the centroid oriented methods (such as K-means) fail by construction. In particular, an exceptionally simple but difficult situation is addressed when cluster centroids coincide, and one can differentiate between the clusters only on the basis of their variance. Performance of the proposed approach is tested on synthetic and real datasets. 相似文献
997.
Lukáš Bučinský Stanislav Biskupič Dylan Jayatilaka 《Theoretical chemistry accounts》2011,129(2):181-197
The 2nd order Douglas-Kroll-Hess (DKH2) and the Infinite Order Two Component (IOTC) radial distributions of electron density
of canonical Hartree-Fock (HF) orbitals of radon atom are presented. Furthermore, the total electron density is revisited.
The picture change error (PCE) correction is investigated by analytical means. The point charge model of nucleus and the Gaussian
nucleus model are employed. The basis set is extrapolated by means of including tight s and also p Gaussians within the original triple zeta basis set. It is found that the DKH1 PCE corrected DKH2 total electron and s orbital contact densities are negative for the point charge model of nucleus if tight enough s Gaussians are included in the basis set. It is shown that this failure is caused due to the missing terms of the second order
Douglas-Kroll transformation for the DKH2 electron density. PCE is found the most striking in the DKH2/IOTC electron density
of s orbitals close to the nucleus. The radial distributions of the 2-component p
1/2 orbital densities are considerably affected by PCE at the nucleus as well. Furthermore, the PCE corrected DKH2/IOTC scalar
p orbital densities have a non-zero value of electron density at nucleus and can be considered as an spin-orbit (SO) average
of the p
1/2 and p
3/2 orbitals. The d and f orbitals are affected by PCE in the vicinity of the nucleus only little. The PCE corrected DKH2 and IOTC radial distributions
of orbital densities are nodeless, which is completely in agreement with the radial distribution of the analytic or numeric
DCH orbital densities. 相似文献
998.
We prove a limit theorem in the space of analytic functions for the Hurwitz zeta-function with algebraic irrational parameter. 相似文献
999.
Xinyi. Cai Dr. Alessandra Lucini Paioni Agnes Adler Ru Yao Wenxiao Zhang David Beriashvili Adil Safeer Andrei Gurinov Prof. Antal Rockenbauer Prof. Dr. Yuguang Song Prof. Dr. Marc Baldus Prof. Dr. Yangping Liu 《Chemistry (Weinheim an der Bergstrasse, Germany)》2021,27(50):12758-12762
Dynamic nuclear polarization (DNP) is a powerful method to enhance the sensitivity of solid-state magnetic nuclear resonance (ssNMR) spectroscopy. However, its biomolecular applications at high magnetic fields (preferably>14 T) have so far been limited by the intrinsically low efficiency of polarizing agents and sample preparation aspects. Herein, we report a new class of trityl-nitroxide biradicals, dubbed SNAPols that combine high DNP efficiency with greatly enhanced hydrophilicity. SNAPol-1, the best compound in the series, shows DNP enhancement factors at 18.8 T of more than 100 in small molecules and globular proteins and also exhibits strong DNP enhancements in membrane proteins and cellular preparations. By integrating optimal sensitivity and high resolution, we expect widespread applications of this new polarizing agent in high-field DNP/ssNMR spectroscopy, especially for complex biomolecules. 相似文献
1000.
Electronic absorption spectroscopy was employed to study the aerial oxidation of catechol (1,2-benzenediol) in alkaline aqueous solution containing an excess of Mg(II) ions. Graphical analysis by the matrix method of UV spectra recorded at regular time intervals gave a good fit for two absorbing species in solution. Based on this result and our earlier ESR spectroscopic investigations we concluded that two main absorbing species in this system are Mg(II)-spin stabilized o-benzosemiquinone anion radical and C-C dimer formed by the nucleophilic attack of catecholate anion on o-benzoquinone. Although the formation of 1,2,4-benzenetriol during the catechol oxidation has been detected in some ESR studies its presence was not indicated by this analysis probably because of the low and/or stable steady state concentration throughout the experiment. 相似文献