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121.
针对一般本科院校信息与计算科学专业毕业设计存在的问题,结合培养目标和专业特色,提出毕业设计改革思路.从选题、质量监控、过程管理、专业基础与内涵和指导教师队伍建设等方面实施相应的改革措施. 相似文献
122.
Velusamy B. Subramanian Naresh Kumar Katari Thirupathi Dongala Sreekantha B. Jonnalagadda 《Biomedical chromatography : BMC》2020,34(1):e4719
A quality by design (QbD) based high-resolution HPLC method is described for determination of impurities in apixaban (APX) in the tablet dosage form. Employing a simple and stability-indicating HPLC method, nine known impurities were quantified with good peak resolution. Mobile phase A (MP-A) was prepared with buffer and acetonitrile 90:10 v/v, while mobile phase B (MP-B) contained water and acetonitrile 10:90 v/v. The gradient program was 0 min, MP-A 75%, B 25%; 20 min, MP-A 65%, B 35%; 30 min, MP-A 40%, B 60%; 40min, MP-A 40%, B 60%; 42 min, MP-A 75%, B 25%; and 50 min, MP-A 75%, B 25%. The chromatographic separation was achieved using a Zorbax RX C18 250 × 4.6 mm column, 5 μm (1.0 ml min−1, 280 nm, 50 μl) and a column temperature of 40°C. Several separation studies were carried out using design of experiments to optimize the method. Validation results confirm the applicability of the developed method for quality analysis and stability studies of the regular product on the manufacturing stream. 相似文献
123.
Daniel Palací-López Pedro Villalba Pierantonio Facco Massimiliano Barolo Alberto Ferrer 《Journal of Chemometrics》2020,34(6):e3230
Latent variable regression model (LVRM) inversion is a relevant tool for finding, if they exist, different combinations of manufacturing conditions that yield the desired process outputs. Finding the best manufacturing conditions can be done by optimizing an appropriately formulated objective function using nonlinear programming. To this end, different formulations of the optimization problem based on LVRM inversion have been proposed in the literature that allow the use of happenstance data (eg, historical data) for this purpose, present lower computational costs than optimizing in the space of the original variables, and guarantee that the solution will conform to the correlation structure of available data from the past. However, these approaches, as presented, suffer from some limitations, such as having to actively modify the constraints imposed on the solution to achieve different sets of conditions to those available in the LVRM calibration dataset, or the lack of a standardized approach for optimizing a linear combination of variables. Furthermore, when minimizing or maximizing one or more outputs, a severe handicap is also present related to the definition of arbitrarily low or high “desired” values. This paper aims at tackling all of these issues. The resulting proposed formulation of the optimization problem is illustrated with three case studies. 相似文献
124.
Prof. Yukishige Ito Prof. Yasuhiro Kajihara Prof. Yoichi Takeda 《Chemistry (Weinheim an der Bergstrasse, Germany)》2020,26(67):15461-15470
The introduction of Asn-linked glycans to nascent polypeptides occurs in the lumen of the endoplasmic reticulum of eukaryotic cells. After the removal of specific sugar residues, glycoproteins acquire signals in the glycoprotein quality control (GPQC) system and enter the folding cycle composed of lectin-chaperones calnexin (CNX) and calreticulin (CRT), glucosidase II (G-II), and UDP-Glc:glycoprotein glucosyltransferase (UGGT). G-II initiates glycoproteins’ entry and exit from the cycle, and UGGT serves as the “folding sensor”. This account summarizes our effort to analyze the properties of enzymes and lectins that play important roles in GPQC, especially those involved in the CNX/CRT cycle. To commence our study, general methods for the synthesis of high-mannose-type glycans and glycoproteins were established. Based on these, various substrates to analyze components of the GPQC were created, and properties of CRT, G-II, and UGGT have been clarified. 相似文献
125.
126.
Leonard J. Barbour 《Journal of Applied Crystallography》2020,53(4):1141-1146
X‐Seed is a native Microsoft Windows program with three primary functions: (i) to serve as a graphical user interface to the SHELX suite of programs, (ii) to facilitate exploration of crystal packing and intermolecular interactions, and (iii) to generate high‐quality molecular graphics artwork suitable for publication and presentation. Development of X‐Seed Version 1.0 began in 1998, when point‐and‐click crystallographic software was still limited in scope and power. Considerable enhancements have been implemented within X‐Seed over the past two decades. Of particular importance are support for the SHELX2019 programs (SHELXS, SHELXD, SHELXT and SHELXL) for structure solution and refinement, and MSRoll for rendering void spaces in crystal structures. The current version (i.e. Version 4) of X‐Seed has a new interface designed to be more interactive and user friendly, and the software can be downloaded and used free of charge. 相似文献
127.
Juraj Kajan Mikhail Volkov Grigori Damazyan Ivan Mukhin Tomáš Gregor Oleg Palashov 《Crystal Research and Technology》2020,55(12):2000105
The research conducted herein builds upon the achievement of a successful and stable 170 × 300 × 35 mm YAG and 5% Yb:YAG single-crystals production via the horizontal directed crystallization method. Based on the analysis of residual birefringence pattern in analyzed ingots, a hypothesis is proposed—debating that in certain stages of the growth, {211} facets start to form within some sections of the crystallization front. The sensitivity of the {211} facets to temperature fluctuations seems to cause striations in the facets’ growth sectors. In a later stage of the growth process the slope of the crystallization front naturally changes, which seems to reduce the formation of facets considerably. As a result, the rear part of the crystal achieves the best optical quality. The samples extracted from that portion of the ingot, after annealing, possess good optical quality and heat release of 0.004 1/m at 1070 nm, which is quite low, and is considered a good result for the garnet family of crystals. The lasing experiment with thin-disk geometry shows a slope efficiency of 52% and proves that the material is suitable for high-power lasers application. 相似文献
128.
考察了分梳辊针布规格及其速度配置与转杯纱质量的关系,为工厂分梳辊针布的合理选择、转杯纱低捻工艺提供参考。 相似文献
129.
对皖东南低山丘陵地区１２个国有林场杉木人工林进行调查,用层次分析法对立地质量进行数量化评定,评定的结果与情况吻合;分析杉木各生长因子和产量之间的关系,用ＳＡＳ软件建立了蓄积,树高,胸径的数学预测模型,所建的模型把年龄,林分密度和立地指数有机结合起来,为该地区杉木人工林生长预测和产量预测提供可靠的依据。 相似文献
130.
辽宁省泥炭资源及其利用 总被引：2，自引：0，他引：2
辽宁省泥炭储量为３５３６．２７万ｔ,分有裸露泥炭和埋藏泥炭。其中辽东山地为泥炭丰富区,以裸露泥炭为主,辽南丘陵沿海为泥炭多量区,以埋藏泥炭为主,其它地区泥炭较少,早期泥炭形成于早全新世辽南沿海,中全新世渐次向北扩展,为泥炭旺盛形成时期,晚全新世南部沼泽被埋藏,北部继续发育,全省泥炭以草木富营养型为主,其中尤以新宾泥炭质量为佳,辽宁泥炭在工业,农业等方面有着广泛的应用。 相似文献