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991.
Adela timac Tihana Kurtovi Nediljko Pavlovi Beata Halassy 《Molecules (Basel, Switzerland)》2022,27(5)
Quality control of human immunoglobulin formulations produced by caprylic acid precipitation necessitates a simple, rapid, and accurate method for determination of residual caprylic acid. A high-performance liquid chromatography method for that purpose was developed and validated. The method involves depletion of immunoglobulins, the major interfering components that produce high background noise, by precipitation with acetonitrile (1:1, v/v). Chromatographic analysis of caprylic acid, preserved in supernatant with no loss, was performed using a reverse-phase C18 column (2.1 × 150 mm, 3 μm) as a stationary phase and water with 0.05% TFA–acetonitrile (50:50, v/v) as a mobile phase at a flow rate of 0.2 mL/min and run time of 10 min. The developed method was successfully validated according to the ICH guidelines. The validation parameters confirmed that method was linear, accurate, precise, specific, and able to provide excellent separation of peaks corresponding to caprylic acid and the fraction of remaining immunoglobulins. Furthermore, a 24−1 fractional factorial design was applied in order to test the robustness of developed method. As such, the method is highly suitable for the quantification of residual caprylic acid in formulations of human immunoglobulins for therapeutic use, as demonstrated on samples produced by fractionation of convalescent anti-SARS-CoV-2 human plasma at a laboratory scale. The obtained results confirmed that the method is convenient for routine quality control. 相似文献
992.
建立了同时测定头发中10种蛋白同化激素液相色谱-串联质谱(LC/MS/MS)分析方法。头发样品经NaOH消解、戊烷液液提取后,用反相液相色谱分离,电喷雾正离子源进行离子化,用多反应监测方式(MRM)对这10种蛋白同化激素的母离子及子离子进行监测,三重四极杆质谱测定。10种蛋白同化激素的检出限为1~20ng/g;相对标准偏差(RSD)为1.72%~13.77%;回收率为38.20%~110.38%;线性回归系数(R2)为0.9958~0.9999。本方法简便快速、灵敏度高、专属性强,可满足在兴奋剂检测或毒物分析中对毛发中蛋白同化激素测定的要求。 相似文献
993.
994.
We reconsider model II of Orban et al. (J. Chem. Phys. 1968, 49, 1778–1783), a two-dimensional lattice-gas system featuring a crystalline phase and two distinct fluid phases (liquid and vapor). In this system, a particle prevents other particles from occupying sites up to third neighbors on the square lattice, while attracting (with decreasing strength) particles sitting at fourth- or fifth-neighbor sites. To make the model more realistic, we assume a finite repulsion at third-neighbor distance, with the result that a second crystalline phase appears at higher pressures. However, the similarity with real-world substances is only partial: Upon closer inspection, the alleged liquid–vapor transition turns out to be a continuous (albeit sharp) crossover, even near the putative triple point. Closer to the standard picture is instead the freezing transition, as we show by computing the free-energy barrier relative to crystal nucleation from the “liquid”. 相似文献
995.
Yibo Li Lingxiao Zhao Laiquan Shi Lingshang Lin Qinghe Cao Cunxu Wei 《Molecules (Basel, Switzerland)》2022,27(6)
Sweet potato is a root tuber crop and an important starch source. There are hundreds of sweet potato varieties planted widely in the world. Starches from varieties with different genotype types and originating from different countries have not been compared for their physicochemical properties. In the research, starches from 44 sweet potato varieties originating from 15 countries but planted in the same growing conditions were investigated for their physicochemical properties to reveal the similarities and differences in varieties. The results showed that the 44 starches had granule size (D[4,3]) from 8.01 to 15.30 μm. Starches had different iodine absorption properties with OD680 from 0.259 to 0.382 and OD620/550 from 1.142 to 1.237. The 44 starches had apparent amylose content from 19.2% to 29.2% and true amylose content from 14.2% to 20.2%. The starches exhibited A-, CA-, CC-, or CB-type X-ray diffraction patterns. The thermograms of 44 starches exhibited one-, two-, or three-peak curves, leading to a significantly different gelatinization temperature range from 13.1 to 29.2 °C. The significantly different starch properties divide the 44 sweet potato varieties into different groups due to their different genotype backgrounds. The research offers references for the utilization of sweet potato germplasm. 相似文献
996.
Unusual current‐voltage characteristics of single crystalline and bicrystalline La0.7Ca0.3MnO3 films
The current‐voltage characteristics of single crystalline and bicrystalline La0.7Ca0.3MnO3 films were measured and analyzed. Several epitaxial films, as well as 45° [001]‐tilt grain boundaries, display current‐voltage characteristics which are asymmetric with respect to polarity reversal of the bias current. One epitaxial film has a polarity dependent resistance of ~340kΩ and of ~670kΩ in forward and in reverse direction, respectively. 相似文献
997.
A suitable derivative of Einstein's equations in the framework of the teleparallel equivalent of general relativity (TEGR) yields a continuity equation for the gravitational energy‐momentum. In particular, the time derivative of the total gravitational energy is given by the sum of the total fluxes of gravitational and matter fields energy. We carry out a detailed analysis of the continuity equation in the context of Bondi and Vaidya's metrics. In the former space‐time the flux of gravitational energy is given by the well known expression in terms of the square of the news function. It is known that the energy definition in the realm of the TEGR yields the ADM (Arnowitt‐Deser‐Misner) energy for appropriate boundary conditions. Here we show that the same energy definition also describes the Bondi energy. The analysis of the continuity equation in Vaidya's space‐time shows that the variation of the total gravitational energy is determined by the energy flux of matter only. 相似文献
998.
999.
1000.
Comparative analysis of the luminescent properties of Y3Al5O12:Ce (YAG:Ce) transparent optical ceramics (OС) with those of single crystal (SC) and single crystalline film (SCF) analogues has been performed under excitation by pulsed synchrotron radiation in the fundamental absorption range of YAG host. It has been shown that the properties of YAG:Ce OC are closer to the properties of the SCF counterpart, where YAl antisite defects are completely absent, rather than to the properties of SC of this garnet with large concentration of YAl antisite defects. At the same time, the luminescence spectra of YAG:Ce OC show weak emission bands in the 200-470 nm range related to YAl antisite defects and charged oxygen vacancies (F+ and F centers). YAG:Ce ОС also possesses significantly larger contribution of slow components in the Ce3+ luminescence decay under high-energy excitation in comparison with SC and SCF of this garnet due to the involvement of antisite defects, charged oxygen vacancies as well as boundaries of grains in the energy transfer processes from the host to the Ce3+ ions. 相似文献