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101.
Open source paradigm is becoming widely accepted in scientific communities and open source hardware is finding its steady place in chemistry research. In this review article, we provide the reader with the most up‐to‐date information on open source hardware and software resources enabling the construction and utilization of an “open source capillary electrophoresis instrument”. While CE is still underused as a separation technique, it offers unique flexibility, low‐cost, and high efficiency and is particularly suitable for open source instrumental development. We overview the major parts of CE instruments, such as high voltage power supplies, detectors, data acquisition systems, and CE software resources with emphasis on availability of the open source information on the web and in the scientific literature. This review is the first of its kind, revealing accessible blueprints of most parts from which a fully functional open source CE system can be built. By collecting the extensive information on open source capillary electrophoresis in this review article, the authors aim at facilitating the dissemination of knowledge on CE within and outside the scientific community, fosters innovation and inspire other researchers to improve the shared CE blueprints. 相似文献
102.
Chunye Liu Xuejiao Zhang Hui Jing Jingshui Zhang Yanqing Miao Xifeng Zhai Songyi Chen 《Electrophoresis》2019,40(2):289-295
An open‐tubular capillary electrochromatography method has been developed for the determination of binding constants between β2‐adrenergic receptor (β2‐AR) and seven drugs. β2‐AR was oriented immobilized onto one part of inner surface of capillary via microwave‐assisted technical synthesis. According to the linear relationship between coating length and the apparent mobility of analyte, the binding constant (Kb) can be obtained by related theories and equations. The order of Kb values between drugs such as adrenaline hydrochloride, norepinephrine bitartrate, and propranolol hydrochloride with β2‐AR is well consistent with that reported in the literature. By the method, Kb values between four extracts of Radix Paeoniae Rubra and β2‐AR were also successfully obtained. Subsequently, computer models were applied to interpret the CEC experiments. And the results proved to be in good agreement with the method. The work, herein, demonstrates the potential of the method in drug‐receptor affinity interactions evaluation and screening of lead compounds from natural sources. 相似文献
103.
Y. F. Gui W. B. Dou K. Yin P. G. Su 《International Journal of Infrared and Millimeter Waves》2008,29(8):782-791
As low loss dielectric materials, ZnS, MgF2, MgAl2O4 and quartz ceramic have a very important application at millimeter frequencies. However, there is little information about
their dielectric properties in the millimeter wavelength band. To obtain their dielectric properties, an automatic open resonator
measurement system at Ka-band is designed and constructed. The importance on the precision determination of cavity length
over a broad band and the checking of a measurement system are emphasized and their solutions are put forward in this paper
for the first time so far as we know. The solutions of above problems ensure the credibility and high accuracy of our measurement
system. The certified measurement system after a series of checking is used to measure the above materials. Lots of measurement
results show that the standard deviation of measurement error is less than 0.154% in permittivity and 20.42% in loss tangent.
Meanwhile, some experimental summaries on the open resonator technique are provided. Software that controls the measurement
system is developed and it improves the testing efficiency greatly. 相似文献
104.
Noury F Mispelter J Szeremeta F Même S Doan BT Beloeil JC 《Magnetic resonance imaging》2008,26(10):1421-1432
Intervertebral disc (IVD) degeneration is a complex process characterized by biochemical and structural changes in both the nucleus pulposus and the anulus fibrosus. In this study, we were able to obtain in vivo magnetic resonance (MR) images of the rabbit spine, with several MR imaging (MRI) contrasts (ρ, T1 and T2). We quantified several parameters (T2, apparent diffusion coefficient, disc height and area) to differentiate between healthy and degenerative IVDs and to characterize the degeneration process. To our knowledge, there has not been any previous in vivo study of rabbit IVDs at high-field MRI (9.4 T).A custom radio frequency (RF) coil for 9.4 T was designed to match rabbit IVD morphology, to study the degeneration in vivo on a model of human lumbar disease. Our new probe, a custom half-birdcage-type coil, obtains the necessary exploration depth while meeting the requirements for signal homogeneity and sensitivity of the study. This design addresses some of the difficulties with constructing RF coils at high field strengths. 相似文献
105.
《Physics letters. A》2019,383(20):2370-2375
We consider a bosonic Josephson junction in the Bose-Hubbard two-mode approximation where some of the parameters are corrupted by physically meaningful noise processes and study the corresponding relaxation dynamics towards its equilibrium state. We show with numerical simulations that this model can essentially capture all the important features observed in a recent experiment regarding the relaxation dynamics in one-dimensional bosonic Josephson junctions, namely the damped oscillations of the population imbalance and the relative phase, as well as the large final coherence factor. We expect that this work will further motivate research about the origin of relaxation mechanism in these systems. 相似文献
106.
107.
A CE instrument that can be assembled from commercially available components with minimal construction effort is described. Except for the electronic control circuitry no specially made parts are required. It is based on a flexible design of microfluidic, electropneumatic, and electronic sections and different configurations can easily be implemented. Automated injection into the capillary is performed hydrodynamically by the application of a pressure for a controlled length of time. The performance of the device was tested with a contactless conductivity detector by separating different metal ions. In addition, nine metal cations related to the quality of honey were separated in 2.3 min and four honey samples were analysed quantitatively to demonstrate the applicability of the method. 相似文献
108.
A.D. López-Sánchez A.G. Hernández-Díaz D. Vigo R. Caballero J. Molina 《European Journal of Operational Research》2014
The aim of this paper is to solve a real-world problem proposed by an international company operating in Spain and modeled as a variant of the Open Vehicle Routing Problem in which the makespan, i.e., the maximum time spent on the vehicle by one person, must be minimized. A competitive multi-start algorithm, able to obtain high quality solutions within reasonable computing time is proposed. The effectiveness of the algorithm is analyzed through computational testing on a set of 19 school-bus routing benchmark problems from the literature, and on 9 hard real-world problem instances. 相似文献
109.
《Electrophoresis》2018,39(8):1040-1047
Isoelectric focusing (IEF) is a powerful separation method, useful for resolving subtle changes in the isoelectric point of unlabeled proteins. While microfluidic IEF has reduced the separation times from hours in traditional benchtop IEF to minutes, the enclosed devices hinder post‐separation access to the sample for downstream analysis. The two‐layer open IEF device presented here comprises a photopatterned hydrogel lid layer containing the chemistries required for IEF and a thin polyacrylamide bottom layer in which the analytes are separated. The open IEF device produces comparable minimum resolvable difference in isoelectric point and gradient stability to enclosed microfluidic devices while providing post‐separation sample access by simple removal of the lid layer. Further, using simulations, we determine that the material properties and the length of the separation lanes are the primary factors that affect the electric field magnitude in the separation region. Finally, we demonstrate self‐indexed photomasks for alignment‐free fabrication of multi‐domain hydrogels. We leverage this approach to generate arrayed pH gradients with a total of 80 concurrent separation lanes, which to our knowledge is the first demonstration of multiple IEF separations in series addressed by a single pair of electrodes. 相似文献
110.
Yang Yang Yongnan Zhao Jianguo Yu Yang Zhou Nan Pang Hao Su Sha Pang 《无机化学与普通化学杂志》2008,634(10):1780-1784
Two new open‐framework zincophosphites, Zn(H6C4N2S)(HPO3) (TJPU‐4) and [C6N2H14]·[Zn3(HPO3)4] (TJPU‐5) have been hydrothermally synthesized by using 2‐mercapto‐1‐methylimidazole [MMI] and 1,4‐diazabicyclo[2.2.2]octane [DABCO] as templates. TJPU‐4 crystallizes in monoclinic space group P21/c with the cell parameters a = 8.787(4) Å, b = 9.732(4) Å, c = 10.515(4) Å, β = 105.316(6)°, V = 867.3(6) Å3. The structure of TJPU‐4 is constructed by ZnO3S tetrahedron and HPO3 pseudo‐pyramid to generate a layer of 4, 8‐network in bc plane. The organic template locates on the both sides of the 8‐membered rings and bonds to zinc atom through Zn–S bond. TJPU‐5 crystallizes in the triclinic space group with cell parameters a = 9.294 (5) Å, b = 9.976 (5) Å, c = 9.986 (5) Å, α = 85.692 (7)°, β = 82.010 (7)° and γ = 80.184 (7)°, V = 902.1 (8) Å3. A novel 4488 cage is found in TJPU‐5. The connections of Zn(1)O4, Zn(3)O4 and HPO3 groups give rise to an infinite corner‐shared four‐ring chain. Using Zn(2)O4 as four connected bridges, linkages of these chains produce a 3‐D framework with intersecting 8‐ring channels running along [100], [010], [001], [011] and [111] directions. 相似文献