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排序方式: 共有209条查询结果,搜索用时 15 毫秒
51.
52.
Selective Cell Adhesion and Biosensing Applications of Bio‐Active Block Copolymers Prepared by CuAAC/Thiol‐ene Double Click Reactions 下载免费PDF全文
53.
A novel type of thrust system is proposed that operates in air and consists of an emitter of charged droplets and a multigrid electrode system in which the stream of these droplets flows in a constant longitudinal electric field, thereby initiating an air flow. The reactive force caused by the air flow and the efficiency with which the electric current energy is converted into the energy of this flow are estimated. It is shown that if a battery of hydrogen fuel elements is used as a power supply, this method of electrical propulsion makes it possible to reduce energy expenditure more than fourfold as compared to existing propeller vehicles. A feasible scheme is presented for a vehicle using such an engine. 相似文献
54.
Sevinc Tuncagil Dilek Odaci Serhat Varis Suna Timur Levent Toppare 《Bioelectrochemistry (Amsterdam, Netherlands)》2009,76(1-2):169
Two types of bacterial biosensor were constructed by immobilization of Gluconobacter oxydans and Pseudomonas fluorescens cells on graphite electrodes modified with the conducting polymer; poly(1-(4-nitrophenyl)-2,5-di(2-thienyl)-1 H-pyrrole) [SNS(NO2)]. The measurement was based on the respiratory activity of cells estimated by the oxygen consumption at − 0.7 V due to the metabolic activity in the presence of substrate. As well as analytical characterization, the linear detection ranges, effects of electropolymerization time, pH and cell amount were examined by using glucose as the substrate. The linear relationships were observed in the range of 0.25–4.0 mM and 0.2–1.0 mM for G. oxydans and P. fluorescens based sensors, respectively. 相似文献
55.
We explore subspaces of maximal operator spaces (
submaximal spaces) and give a new characterization of such spaces. We show that the set
of n-dimensional submaximal spaces is closed in the topology of c.b. distance,
but not compact. We also investigate subspaces of MAX(L
) and prove that
any homogeneous Hilbertian subspace of MAX(L
1) is completely isomorphic
to R + C. 相似文献
56.
We consider the one-dimensional Burgers equation randomly stirred at large scales by a Gaussian short-time correlated force. Using the method of dissipative anomalies, we obtain velocity and velocity-difference probability density functions and confirm the results with high-resolution numerical simulations. 相似文献
57.
Three-dimensional (3D) relativistic electromagnetic subcycle solitons were observed in 3D particle-in-cell simulations of an intense short-laser-pulse propagation in an underdense plasma. Their structure resembles that of an oscillating electric dipole with a poloidal electric field and a toroidal magnetic field that oscillate in phase with the electron density with frequency below the Langmuir frequency. On the ion time scale, the soliton undergoes a Coulomb explosion of its core, resulting in ion acceleration, and then evolves into a slowly expanding quasineutral cavity. 相似文献
58.
We have developed a method for calculation of quantum fluctuation effects, in particular, of the uncertainty zone developing at the potential curvature sign inversion, for a damped harmonic oscillator with arbitrary time dependence of frequency and for arbitrary temperature, within the Caldeira-Leggett model. The method has been applied to the calculation of the gray zone width Delta Ix of Josephson-junction balanced comparators. The calculated temperature dependence of Delta Ix in the range 1.5 to 4.2 K is in virtually perfect agreement with experimental data for Nb-trilayer comparators with critical current densities of 1.0 and 5.5 kA/cm2, without any fitting parameters. 相似文献
59.
It is proved that if X and Y are operator spaces such that everycompletely bounded operator from X into Y is completely compactand Z is a completely complemented subspace of X Y, then thereexists a completely bounded automorphism : X Y X Y with completelybounded inverse such that Z = X0 Y0, where X0 and Y0 are completelycomplemented subspaces of X and Y, respectively. If X and Yare homogeneous, the existence is proved of such a under aweaker assumption that any operator from X to Y is strictlysingular. An upper estimate is obtained for ||||cb||1||cbif X and Y are separable homogeneous Hilbertian operator spaces.Also proved is the uniqueness of a completely unconditionalbasis in X Y if X and Y satisfy certain conditions. 相似文献
60.
Dr. Yearin Byun Lilia S. Xie Patrick Fritz Timur Ashirov Prof. Mircea Dincă Prof. Ali Coskun 《Angewandte Chemie (Weinheim an der Bergstrasse, Germany)》2020,132(35):15278-15282
Dimensionality plays an important role in the charge transport properties of organic semiconductors. Although three-dimensional semiconductors, such as Si, are common in inorganic materials, imparting electrical conductivity to covalent three-dimensional organic polymers is challenging. Now, the synthesis of a three-dimensional π-conjugated porous organic polymer (3D p-POP) using catalyst-free Diels–Alder cycloaddition polymerization followed by acid-promoted aromatization is presented. With a surface area of 801 m2 g−1, full conjugation throughout the carbon backbone, and an electrical conductivity of 6(2)×10−4 S cm−1 upon treatment with I2 vapor, the 3D p-POP is the first member of a new class of permanently porous 3D organic semiconductors. 相似文献