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71.
Takaya Murakami Reiko Ishimaru Eriko Minami Yoshiaki Iwamuro Naoki Takamura Aya Torai Tsutomu Watanabe Akihiro Miki Munehiro Katagi Maiko Kusano Hitoshi Tsuchihashi Kei Zaitsu Satoshi Chinaka 《Journal of separation science》2023,46(3):2200681
Quick, easy, cheap, effective, rugged, and safe extraction strategies are becoming increasingly adopted in various analytical fields to determine drugs in biological specimens. In the present study, we developed two fully automated quick, easy, cheap, effective, rugged, and safe extraction methods based on acetonitrile salting-out assisted liquid-liquid extraction (method 1) and acetonitrile salting-out assisted liquid-liquid extraction followed by dispersive solid-phase extraction (method 2) using a commercially available automated liquid-liquid extraction system. We applied these methods to the extraction of 14 psychotropic drugs (11 benzodiazepines and carbamazepine, quetiapine, and zolpidem) from whole blood samples. Both methods prior to liquid chromatography–tandem mass spectrometry analysis exhibited high linearity of calibration curves (correlation coefficients, > 0.9997), ppt level detection sensitivities, and satisfactory precisions (< 8.6% relative standard deviation), accuracies (within ± 16% relative error), and matrix effects (81–111%). Method 1 provided higher recovery rates (80–91%) than method 2 (72–86%), whereas method 2 provided higher detection sensitivities (limits of detection, 0.003–0.094 ng/mL) than method 1 (0.025–0.47 ng/mL) owing to the effectiveness of its dispersive solid-phase extraction cleanup step. These fully automated extraction methods realize reliable, labor-saving, user-friendly, and hygienic extraction of target analytes from whole blood samples. 相似文献
72.
References: 《声学学报:英文版》2008,27(1):85-96
Microphone array-based speech enhancement has great importance for speech communications and speech recognition. To reduce the aperture of the microphone array and to increase the effect of the speech enhancement will greatly broaden the application areas of the microphone array. An array crosstalk resistant adaptive noise cancellation method is therefore presented. And then an improved spectral subtraction algorithm is further cascaded to obtain better enhancement results. Theoretic analysis and experiments indicate that the proposed scheme needs only a very small microphone array while it simultaneously achieves a higher SNR improvement. Besides, the proposed scheme can be used in many noisy environments and is easy for real-time implementation. 相似文献
73.
文武 《达县师范高等专科学校学报》2010,20(5):5-7
运用变量变换的方法将一些特殊类型的一阶微分方程化为了可分离变量的齐次方程、伯努利(Bernoulli)方程或标准的一阶线性微分方程,从而可用初等解法来解这类一阶微分方程. 相似文献
74.
阐述如今高等学府中"浅阅读"风盛行的现象。分析了高校学生"浅阅读"的特点、原因和危害,认为高校图书馆应针对这种状况加强对大学生的导读服务,并为高校图书馆如何应对此现状加强导读服务作出了几点建议。 相似文献
75.
高新宇 《沈阳大学学报:自然科学版》2009,21(6):104-106
分析了新一轮经济周期下辽宁省中长期贷款增长的特点以及存在的主要问题,并对未来货币政策趋势提出了政策建议,确保社会投资和民间投资的及时跟进,注重货币政策工具的搭配,提高货币政策的透明度,进一步完善资本市场,增加直接融资比重。 相似文献
76.
In this note, relationships among the components, structure distribution and easy magnetization direction, structure of magnetic domain of nano-magnetic material in the major mature lateral radula teeth of chiton A.rubrolinestus Lischke are probed by using the high resolution transmission electron microscope (HRTEM), the scanning electron microscope (SEM), the magnetic force microscope (MFM) and the super-conducting quantum interference device (SQUID) magnetometer from the point of view of magnetism to provide a basis for comprehending biologic function of the magnetic radula.`` 相似文献
77.
Choice of crucible material is a key issue during the growth of AlN crystal. The stabilities at high temperature and life-spans of boron nitride (BN) crucible,tantalum (Ta) crucible and tungsten (W) crucible were compared. Tantalum crucible behaved worse at high temperature and life-span was shortened as compared with the other two crucible materials. It was very crisp and easy to crack. In contrast,self-seeded AlN crystals with different morphologies could be obtained at different high temperatures using BN crucible. The boron nitride crucible was stable below 2200 ℃,above which it would decompose. Thus it was unsuitable for the bulky AlN crystal growth. Tungsten crucible could endure the temperatures higher than 2200℃. Unfortunately we could only get AlN polycrystallines using tungsten crucible. After 50~100 hours’ run,the crucible was destroyed completely due to the multiple deep cracks. XRD results of destroyed tungsten crucible indicated that the main phases are tungsten carbide and tungsten nitride. 相似文献
78.
针对自然语言处理(Natural Language Processing, NLP)任务中,命名实体识别(Named Entity Recognition, NER)存在实体类别样本不平衡的问题,提出一种基于改进损失函数的实体类别平衡优化算法。新算法是对神经网络模型中的损失函数进行优化处理,通过分析命名实体识别数据特点,在平衡正负样本的基础上引入平滑系数和权重系数,保证模型在梯度传递的过程更关注于实体类别较少和带有嵌套的难识别样本,同时减少对样本数较多的、易识别样本的关注。利用公共数据集ACE05、MSRA进行实验对比,结果表明改进的损失函数在数据集ACE05和MSRA上,F1值分别提高1.53%和0.91%。上述结果表明改进的损失函数能够较好地缓解实体中正负难易样本的不平衡。 相似文献
79.
Panpan Pan Xiao Chen Huaran Xing Yonghui Deng Jingdi Chen Fahad A. Alharthi Abdulaziz A. Alghamdi Jiacan Su 《中国化学快报》2021,32(7):2159-2163
Injectable hydrogels have been considered as promising materials for bone regeneration,but their osteoinduction and mechanical performance are yet to be improved.In this study,a novel biocompatible injectable and self-healing nano hybrid hydrogel was on-demand prepared via a fast(within 30 s) and easy gelation approach by reversible Schiff base formed between-CH=O of oxidized sodium alginate(OSA) and-NH_2 of glycol chitosan(GCS) mixed with calcium phosphate nanoparticles(CaP NPs).Its raw materials can be ready in large quantities by a simple synthesis process.The mechanical strength,degradation and swelling behavior of the hydrogel can be readily controlled by simply controlling the molar ratio of-CH=O and-NH_2.This hydrogel exhibits pH responsiveness,good degradability and biocompatibility.The hydrogel used as the matrix for mesenchymal stem cells can significantly induce the proliferation,differentiation and osteoinduction in vitro.These results showed this novel hydrogel is an ideal candidate for applications in bone tissue regeneration and drug delivery. 相似文献
80.
Innovative mixture of salts in the quick,easy, cheap,effective, rugged,and safe method for the extraction of residual macrolides in milk followed by analysis with liquid chromatography and tandem mass spectrometry
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Rafaela Pinto da Costa Bernardete Ferraz Spisso Mararlene Ulberg Pereira Mychelle Alves Monteiro Rosana Gomes Ferreira Armi Wanderley da Nóbrega 《Journal of separation science》2015,38(21):3743-3749
A simple extraction technique has been developed for seven macrolide antibiotics in milk. The procedure involves a modified quick, easy, cheap, effective, rugged, and safe method based on acetonitrile extraction, followed by the addition of a mixture of salts (sodium sulfate, sodium chloride, and potassium carbonate) not yet reported in literature. The method was validated for tylosin and was selective, free of matrix effect, and linear in the range of 0.78–18.75 ng/mL in the final extract, corresponding to 0.125–3 times the maximum residue limit. The limit of detection, limit of quantification, decision limit, and detection capability were, respectively, 0.84, 2.79, 58.4, and 71.7 μg/kg. The overall average recovery at 25, 50, and 75 μg/kg ranged from 89–97%. Repeatability and intermediate precision expressed by relative standard deviations were below 10.5 and 12%, respectively. The extension of the validation for spiramycin, throleandomycin, oleandomycin, roxithromycin, erythromycin, and clarithromycin is under consideration since the procedure proved to be able to efficiently extract all studied macrolides, with recoveries from 74–104% at 50 μg/kg for tylosin, erythromycin, spiramycin, and oleandomycin and 20 μg/kg for throleandomycin, roxithromycin, and clarithromycin. 相似文献