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101.
Kaszuba Natalia Kasprzyk-Kucewicz Teresa Bałamut Karolina Morawiec Tadeusz Stanek Agata Wziątek-Kuczmik Daria Cholewka Armand 《Journal of Thermal Analysis and Calorimetry》2022,147(12):6745-6753
Journal of Thermal Analysis and Calorimetry - The main goal of this study was to find out if thermal imaging may be useful in the evaluation of two types of anaesthetic injections—with and... 相似文献
102.
Natalia V. Kuratieva Daria Mikhailova Helmut Ehrenberg 《Acta Crystallographica. Section C, Structural Chemistry》2009,65(11):i85-i86
A new polymorph of nonacopper(II) bis(orthoborate) bis(hexaoxodiborate), Cu9(BO3)2(B2O6)2, or Cu3B2O6 with Z′ = 3, has a pseudo‐layered monoclinic structure containing BO3 triangles and B2O6 units consisting of corner‐sharing BO3 triangles and BO4 tetrahedra. The compound was obtained during an investigation of the Li–Cu–B–O system. In contrast to the triclinic form of Cu3B2O6, the layers are linked to one another by BO4 tetrahedra. 相似文献
103.
Wong TS Zhurina D Schwaneberg U 《Combinatorial chemistry & high throughput screening》2006,9(4):271-288
Over the past decade, we have witnessed a bloom in the field of evolutive protein engineering which is fueled by advances in molecular biology techniques and high-throughput screening technology. Directed protein evolution is a powerful algorithm using iterative cycles of random mutagenesis and screening for tailoring protein properties to our needs in industrial applications and for elucidating proteins' structure function relationships. This review summarizes, categorizes and discusses advantages and disadvantages of random mutagenesis methods used for generating genetic diversity. These random mutagenesis methods have been classified into four main categories depending on the method employed for nucleotide substitutions: enzyme based methods (Category I), synthetic chemistry based methods (Category II), whole cell methods (Category III) and combined methods (Category I-II, I-III and II-III). The basic principle of each method is discussed and varied mutagenic conditions are summarized in Tables and compared (benchmarked) to each other in terms of: mutational bias, controllable mutation frequency, ability to generate consecutive nucleotide substitutions and subset diversity, dependency on gene length, technical simplicity/robustness and cost-effectiveness. The latter comparison shows how highly-biased and limited current diversity creating methods are. Based on these limitations, strategies for generating diverse mutant libraries are proposed and discussed (RaMuS-Flowchart; KISS principle). We hope that this review provides, especially for researchers just entering the field of directed evolution, a guide for developing successful directed evolution strategies by selecting complementary methods for generating diverse mutant libraries. 相似文献
104.
Daria Michalik 《Topology and its Applications》2010,157(7):1228-1236
We prove that there is the universal space for the class of n-dimensional separable metric spaces in the Cartesian product K1×?×Kn+1 of Peano curves without free arcs. It is also shown that the set of embeddings of any n-dimensional separable metric space X into this universal space is a residual set in C(X,K1×?×Kn+1). Other properties of product of Peano curves without free arcs are also proved. 相似文献
105.
Nikita M. Kondratiev Valery E. Lobanov Artem E. Shitikov Ramzil R. Galiev Dmitry A. Chermoshentsev Nikita Yu. Dmitriev Andrey N. Danilin Evgeny A. Lonshakov Kirill N. Min’kov Daria M. Sokol Steevy J. Cordette Yi-Han Luo Wei Liang Junqiu Liu Igor A. Bilenko 《Frontiers of Physics》2023,18(2):21305
The stabilization and manipulation of laser frequency by means of an external cavity are nearly ubiquitously used in fundamental research and laser applications. While most of the laser light transmits through the cavity, in the presence of some back-scattered light from the cavity to the laser, the self-injection locking effect can take place, which locks the laser emission frequency to the cavity mode of similar frequency. The self-injection locking leads to dramatic reduction of laser linewidth and noise. Using this approach, a common semiconductor laser locked to an ultrahigh-Q microresonator can obtain sub-Hertz linewidth, on par with state-of-the-art fiber lasers. Therefore it paves the way to manufacture high-performance semiconductor lasers with reduced footprint and cost. Moreover, with high laser power, the optical nonlinearity of the microresonator drastically changes the laser dynamics, offering routes for simultaneous pulse and frequency comb generation in the same microresonator. Particularly, integrated photonics technology, enabling components fabricated via semiconductor CMOS process, has brought increasing and extending interest to laser manufacturing using this method. In this article, we present a comprehensive tutorial on analytical and numerical methods of laser self-injection locking, as well a review of most recent theoretical and experimental achievements. 相似文献
106.
Anton Zalygin Daria Solovyeva Ivan Vaskan Dr. Stephen Henry Dr. Marcel Schaefer Dr. Pavel Volynsky Dr. Alexander Tuzikov Dr. Elena Korchagina Dr. Ivan Ryzhov Dr. Alexey Nizovtsev Dr. Konstantin Mochalov Prof. Roman Efremov Dr. Eleonora Shtykova Dr. Vladimir Oleinikov Prof. Nicolai Bovin 《ChemistryOpen》2020,9(6):641-648
The synthetic function-spacer-lipid (FSL) amphiphile biotin-CMG-DOPE is widely used for delicate ligation of living cells with biotin residues under physiological conditions. Since this molecule has an “apolar-polar-hydrophobic” gemini structure, the supramolecular organization is expected to differ significantly from the classical micelle. Its organization is investigated with experimental methods and molecular dynamics simulations (MDS). Although the linear length of a single biotin-CMG-DOPE molecule is 9.5 nm, the size of the dominant supramer globule is only 14.6 nm. Investigations found that while the DOPE tails form a hydrophobic core, the polar CMG spacer folds back upon itself and predominantly places the biotin reside inside the globule or planar layer. MDS demonstrates that <10 % of biotin residues on the highly water dispersible globules and only 1 % of biotin residues in layer coatings are in an linear conformation and exposing biotin into the aqueous medium. This explains why in biotin-CMG-DOPE apolar biotin residues both in water dispersible globules and coatings on solid surfaces are still capable of interacting with streptavidin. 相似文献
107.
Minerals in the rosasite mineral group namely rosasite, glaucosphaerite, kolwezite, mcguinnessite have been studied by powder X-ray diffraction, scanning electron microscopy and infrared spectroscopy. X-ray diffraction shows the minerals to be complex mixtures with more than one rosasite mineral observed in each sample. SEM analysis shows the minerals to be fibrous in nature and the use of EDAX enabled the chemical composition of the minerals to be determined. The spectral patterns for the minerals rosasite, glaucosphaerite, kolwezite and mcguinnessite are similar to that of malachite implying the molecular structure is similar to malachite. A comparison is made with the spectrum of malachite. The rosasite mineral group is characterised by two OH stretching vibrations at ∼3401 and 3311 cm−1. Two intense bands observed at ∼1096 and 1046 cm−1 are assigned to ν1 (CO3)2− symmetric stretching vibration and the δ OH deformation mode. Multiple bands are found in the 800–900 and 650–750 cm−1 regions attributed to the ν2 and ν4 bending modes confirming the symmetry reduction of the carbonate anion in the rosasite mineral group as C2v or Cs. A band at ∼560 cm−1 is assigned to a CuO stretching mode. 相似文献
108.
Yvonne Abel Elmar Haake Gerold Haake Wolfgang Schmidt Daria Struve Andreas Walter Franz-Peter Montforts 《Helvetica chimica acta》1998,81(11):1978-1996
A Simple and Flexible Synthesis of Pyrroles from α , β -Unsaturated Sulfones: The addition of alkyl isocyanoacetates and isocyanoacetonitrile to α,β-unsaturated sulfones affords a convenient and broad access to pyrroles with unusual substitution patterns (see Scheme 2). The α,β-unsaturated sulfones required as starting materials are easily obtained from different olefines. 相似文献
109.
110.
Malgorzata Zieba Daria Wieczorek Emilia Klimaszewska Anna Malysa Dobrawa Kwasniewska 《Journal of Dispersion Science and Technology》2013,34(8):1189-1196
AbstractThe purpose of the study was to applicate new synthesized zwitterionic surfactants as hair shampoo components. Hair shampoos formulated for the study contained newly synthesized sulfobetaines at a concentration of 2%. The above additives were evaluated to determine their effect on shampoo dynamic viscosity, texture, yield stress, foaming properties and surface tension of aqueous shampoo solutions. The viscosity of the sulfobetaine-enriched hair shampoos ranged between 6,000 and 21,000?mPa·s, which ensures the required application properties of the formulated products. The yield stress in three prototypical shampoos was equal to approximately 10?Pa, which represents the minimum value that should characterize cosmetics of this type. The sulfobetaines added to the formulations were not found to significantly affect the parameters of hardness and adhesive force. All the formulations under study, except for the shampoo containing N-dodecyl-N-piperidinium-1-propanesulfonate, exhibited good foaming properties. The incorporation of sulfobetaines into hair shampoos contributes to an effective decrease in the surface tension of their aqueous solutions, which may indicate beneficial washing properties. The use of the proposed sulfobetaines in hair shampoos favorably modifies their physicochemical and functional properties. The findings of the study can provide useful insights for the formulation of hair shampoos containing zwitterionic surfactants. 相似文献