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91.
YANG Wei-wei DI You-ying LI Jing KONG Yu-xia 《高等学校化学研究》2010,26(2):304-308
The crystal structure of ephedrine hydrochloride was determined by means of X-ray crystallography.The crystal system of the compound is monoclinic,and the space group is P21.Unit cell parameters are a=0.7308(6) nm,b=0.6124(5) nm,and c=1.2618(11) nm;α=90°,β=102°,and γ=90°;Z=2.Low-temperature heat capacities of the title compound were measured with an improved precision automated adiabatic calorimeter over a temperature range from 77 K to 396 K.A polynomial equation of the heat capacities as a function of temperature in the temperature region was fitted by the least-squares.Based on the fitted polynomial equation,the smoothed heat capacities and thermodynamic functions of the compound relative to the standard reference temperature 298.15 K were calculated and tabulated at the intervals of 5 K. 相似文献
92.
Marla D. Swain George P. Anderson Dan Zabetakis Rachael D. Bernstein Jinny L. Liu Laura J. Sherwood Andrew Hayhurst Ellen R. Goldman 《Analytical and bioanalytical chemistry》2010,398(1):339-348
Single-domain antibodies (sdAb) specific for botulinum neurotoxin serotype A (BoNT A) were selected from an immune llama phage
display library derived from a llama that was immunized with BoNT A toxoid. The constructed phage library was panned using
two methods: panning on plates coated with BoNT A toxoid (BoNT A Td) and BoNT A complex toxoid (BoNT Ac Td) and panning on
microspheres coupled to BoNT A Td and BoNT A toxin (BoNT A Tx). Both panning methods selected for binders that had identical
sequences, suggesting that panning on toxoided material may be as effective as panning on bead-immobilized toxin for isolating
specific binders. All of the isolated binders tested were observed to recognize bead-immobilized BoNT A Tx in direct binding
assays, and showed very little cross-reactivity towards other BoNT serotypes and unrelated protein. Sandwich assays that incorporated
selected sdAb as capture and tracer elements demonstrated that all of the sdAb were able to recognize soluble (“live”) BoNT
A Tx and BoNT Ac Tx with virtually no cross-reactivity with other BoNT serotypes. The isolated sdAb did not exhibit the high
degree of thermal stability often associated with these reagents; after the first heating cycle most of the binding activity
was lost, but the portion of the protein that did refold and recover antigen-binding activity showed only minimal loss on
subsequent heating and cooling cycles. The binding kinetics of selected binders, assessed by both an equilibrium fluid array
assay as well as surface plasmon resonance (SPR) using toxoided material, gave dissociation constants (K
D ) in the range 2.2 × 10−11 to 1.6 × 10−10 M. These high-affinity binders may prove beneficial to the development of recombinant reagents for the rapid detection of
BoNT A, particularly in field screening and monitoring applications. 相似文献
93.
B. Löhden S. Kuznetsova K. Sengstock V. M. Baev A. Goldman S. Cheskis B. Pálsdóttir 《Applied physics. B, Lasers and optics》2011,102(2):331-344
Intracavity absorption spectroscopy with a broadband Er3+-doped fiber laser is applied for the measurements of several molecular species revealing quantitative information about the
gas concentration, temperature and chemical reactions in flames. The spectral range of measurements extends from 6200 cm−1 to 6550 cm−1 with the proper choice of the fiber length and by moving an intracavity lens. With a pulsed laser applied in this experiment,
the sensitivity to absorption corresponds to an effective absorption path length of 3 km assuming the cavity is completely
filled with the sample. For a cw laser, the effective absorption path length is estimated to be 50 km. Absorption spectra
of various molecules such as CO2, CO, H2O, H2S, C2H2 and OH were recorded separately in the cell and/or in low-pressure methane and propane flames. The presented measurements
demonstrate simultaneous in situ detection of three molecular products of chemical reactions at different flame locations.
Variation of the relative strengths of OH absorption lines with the temperature enables the estimation of the local flame
temperature. The sensitivity of this laser does not depend on the broadband cavity losses and it can be used for in situ measurements
of absorption spectra in hostile environments such as contaminated samples, flames or combustion engines. The presented technique
can be applied for various diagnostic purposes, such as in environmental, combustion and plasma research, in medicine and
in the determination of stable isotope ratios. 相似文献
94.
Single electron qubits are attractive for quantum information processing because they offer, for example, the possibility of extremely long coherence times. For scaling up to a large number of coupled qubits, an array of planar Penning traps is a much more promising option than the cylindrical Penning traps within which one-quantum transitions have been observed. This report summarizes optimized trap configurations, discussed at length in Goldman and Gabrielse (Phys Rev A 81:052335, 2010), which promise to make it possible to realize one-electron qubits in a scalable configuration for the first time. 相似文献
95.
借助于基片下方放置的磁铁,在溅射的放电空间中引入了纵向的梯度磁场,辉光放电时,其外貌发生了显著的收缩,由此沉积的薄膜在平面内存在明显的厚度梯度,用磁场中带电粒子的运动理论解释了此种薄膜的形成机制。 相似文献
96.
M. Goldman M. Novaga 《Calculus of Variations and Partial Differential Equations》2012,44(3-4):297-318
We establish existence of compact minimizers of the prescribed mean curvature problem with volume constraint in periodic media. As a consequence, we construct compact approximate solutions to the prescribed mean curvature equation. We also show convergence after rescaling of the volume-constrained minimizers towards a suitable Wulff Shape, when the volume tends to infinity. 相似文献
97.
Rachid Touzani Michael HaibachAgnieszka J. Nawara-Hultzsch Sghir El KadiriThomas J. Emge Alan S. Goldman 《Polyhedron》2011,30(15):2530-2534
The complexation of the simple 1-hydroxymethyl-3,5-dimethylpyrazole (HL) ligand with Fe and Ni salts leads to interesting polynuclear complexes in good yield. X-ray diffraction reveals that the resulting complexes (μ4-L)4Ni4Cl4(H2O)4 and (μ2-L)4(μ3-L)2Fe8Cl16(μ4-O)6 adopt cubane-type and open-cubane-type structures in the solid state. 相似文献
98.
设t≥4,p1,…,pt为不同的模4余1的素数,本文证明了数域P1~(1/2),…,Pt~(1/2)的类数为偶数. 相似文献
99.
MOHAMED SAÏDI 《Compositio Mathematica》1997,107(3):319-338
Let R be a discrete complete valuation ring, with algebraically closedresidue field. Let X be a semi-stable R-curve, with smooth generic fibre. In this paper we study tame coverings of X. 相似文献
100.
本文由Priestley渐进谱理论导出了非平稳随机过程蒙特卡罗模拟的一个谱表示方法.按照该方法,样本过程可直接由一余弦级数公式计算产生.可以证明,当级数项数足够大时,模拟的样本过程可准确地反映非平稳随机过程规定的性质;当产生的样本过程足够多时,其总体均值和总体自相关函数均趋于相应目标函数;样本过程随着级数项数趋于无穷而渐近呈正态分布.本文方法最显著的特点在于可以借助随机相位角产生具有某些预期特征的样本过程. 相似文献