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Journal of Pharmaceutical Analysis 2016年第2期6卷 103-111页

作者： milagros montemurro maría m.de zan juan c.robles Laboratorio de Control de Calidad de medicamentos Facultad de Bioqufmica y Ciendas Biologicas Universidad Nacional del Litoral Santa Fe Argentina

methotrexate （mTX） is an antineoplastic drug, and due to its high toxicity, the therapeutic drug mon- itoring is strictly conducted in the clinical practice. The chemometric optimization and validation of a high performance liquid chromatography （HPLC） method using core-shell particles is presented for the determination of mTX in plasma during therapeutic monitoring. Experimental design and response surface methodology （RSm） were applied for the optimization of the chromatographic system and the analyte extraction step. A Poroshel1120 EC-C18 （3.0 mm × 75 mm, 2.7 μm） column was used to obtain a fast and efficient separation in a complete run time of 4 min. The optimum conditions for the chroma- tographic system resulted in a mobile phase consisting of acetic acid/sodium acetate buffer solution （85.0 mm, pH =4.00） and 11.2% of acetonitrile at a flow rate of 0.4 mL/min. Selectivity, linearity, accuracy and precision were demonstrated in a range of 0.10-6.0 μm of mTX. The application of the optimized method required only 150μL of patient plasma and a low consumption of solvent to provide rapid re- sults.

关键词： HPLC Core-shell particles methotrexate Drug monitoring

multiple responses optimization in the development of a headspace gas chromatography method for the determination of residual solvents in pharmaceuticals

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Journal of Pharmaceutical Analysis 2015年第5期5卷 296-306页

作者： Carla m.Teglia milagros montemurro maría m.de zan maría S.Cmara Laboratorio de Control de Calidad de medicamentos Facultad de Bioquimica y Ciencias BiologicasUniversidad Nacional del Litoral

An efficient generic static headspace gas chromatography （HSGC） method was developed, optimized and validated for the routine determination of several residual solvents （RS） in drug substance, using a strategy with two sets of calibration. Dimethylsulfoxide （DmSO） was selected as the sample diluent and internal standards were used to minimize signal variations due to the preparative step. A gas chroma- tograph from Agilent m.del 6890 equipped with flame ionization detector （FID） and a DB-624 （30 m × 0.53 mm i.d., 3.00 μm film thickness） column was used. The inlet split ratio was 5：1. The influ- encing factors in the chromatographic separation of the analytes were determined through a fractional factorial experimental design. Significant variables： the initial temperature （IT）, the final temperature （FT） of the oven and the carrier gas flow rate （F） were optimized using a central composite design. Response transformation and desirability function were applied to find out the optimal combination of the chromatographic variables to achieve an adequate resolution of the analytes and short analysis time. These conditions were 30 ℃ for IT, 158 ℃ for FT and 1.90 mL/min for F. The method was proven to be accurate, linear in a wide range and very sensitive for the analyzed solvents through a comprehensive validation according to the ICH guidelines.

关键词： Headspace gas chromatographyResidual solventsPharmaceuticalsSurface response methodologydesirabiliW function

New Amphiphilic Amino Acid derivatives for Efficient DNA Transfection in Vitro

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Advances in Chemical Engineering and Science 2017年第2期7卷 191-205页

作者： Lucía C.Pena maría F.Argaraná maría m.de zan Antonella Giorello Sebastián Antuna Claudio C.Prieto Carolina m.I.Veaute Diana m.müller LAQUImAP Dto.Química OrgánicaUniversidad Nacional del LitoralSanta FeArgentina Cát.microbiología General Universidad Nacional del LitoralSanta FeArgentina Laoratorio de Control de medicamentos Universidad Nacional del LitoralSanta FeArgentina Instituto de Investigaciones en Catálisis y Petroquímica Universidad Nacional del LitoralSanta FeArgentina Laboratorio de Cultivos Celulares Universidad Nacional del LitoralSanta FeArgentina Laboratorio de Inmunología Básica Universidad Nacional del LitoralSanta FeArgentina

Nucleic acids-based therapies have recently developed as next-generation agents for treating and preventing viral infection, cancer, and genetic disorders, but their use is still limited due to its relatively poor delivery into targeted cells. We designed and synthesized new amphiphilic amino acid derivatives (cysteine-based) of low molecular weight, formed by the same pentapeptide (AG2: WWCOO) N-acylated, with different hydrophobic chains containing from 12 to 18 carbons, named AG2-Cn (N), which dimerize by oxidation in the presence of pLenti-CmV-GFP Puro plasmid (P) in the respective gemini. We determined transfection efficiency, critical micelle concentration, particle size, ζ-potential and cytotoxicity for the derivatives obtained. We found that all the synthesized compounds were active for DNA delivery and had greater ability to transfect CHO-K1 cells. In particular, AG2-C18 is a promising carrier for gene delivery because it showed no cytotoxicity and its activity was greater than or equal to the commercial actives currently used.

关键词： Amphiphile N-Acylated Cysteine Gemini Ornithine Transfection

浅水中波浪载荷对半潜平台拖航运动响应和拖揽张力影响

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科技导报 2025年第2期43卷 97-107页

作者：张涛白旭昝英飞江苏科技大学船舶与海洋工程学院哈尔滨工程大学船舶工程学院

针对浅水航道水域较浅且环境条件复杂恶劣的现象，以浮筒宽高比过大的新型半潜平台为研究对象，基于时域分析理论和浅水波浪理论，通过数值模型对比分析不同有义波高、谱峰周期、浪向角、拖航速度和拖揽长度对浅水海域半潜平台拖航运动... 详细信息

针对浅水航道水域较浅且环境条件复杂恶劣的现象，以浮筒宽高比过大的新型半潜平台为研究对象，基于时域分析理论和浅水波浪理论，通过数值模型对比分析不同有义波高、谱峰周期、浪向角、拖航速度和拖揽长度对浅水海域半潜平台拖航运动响应和拖揽张力的影响。结果表明：波浪高度越高，平台垂荡、缆绳张力越大；谱峰周期越长，纵摇、缆绳张力越小；浪向角对横纵摇影响较大，极值呈凹凸型分布；不同工况下的新型半潜平台横纵摇均≤5°，满足拖航规范要求；缆绳张力受航速和波高的影响较大，当波高达到5 m，拖揽张力超过安全范围，可以通过降低拖航速度、缩短缆绳长度等措施规避风险。

关键词：浅水海域波浪载荷半潜平台运动响应拖揽张力

A Wideband microwave Holography methodology for Reflector Surface measurement of Large Radio Telescopes

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Research in Astronomy and Astrophysics 2022年第9期22卷 140-151页

作者： zan Wang de-Qing Kong Hong-Bo Zhang Xin-Ying Zhu Ze-Xin Liu Yu-Chen Liu Key Laboratory of Lunar and deep Space Exploration National Astronomical ObservatoriesChinese Academy of SciencesBeijing 100010China University of Chinese Academy of Sciences Beijing 100049China

most reflector surface holographic measurements of a large radio telescope utilize a geostationary satellite as the signal source. The shortcoming is that those measurements could only be done at a limited elevation angle due to the satellite’s relatively stationary state. This paper proposed a new wideband microwave holographic measurement method based on radio sources to achieve full-elevation-angle measurement with small size reference antenna. In theoretical derivation, the time delay and phase change due to path length and device difference between the antenna under test and reference antenna are compensated first. Then the correct method of wideband holography effect, which is because of antenna pattern differing under different wavelengths when receiving a wideband signal, is presented. To verify the proposed methodology, a wideband microwave holographic measurement system is established, the data processing procedure is illustrated, and the reflector surface measurement experiments on a 40 m radio telescope at different elevation angles are conducted. The result shows that the primary reflector surface root-mean-square at around elevation angles of 28°, 44°, 49°, and 75° are respectively 0.213 mm, 0.170 mm, 0.188 mm, and 0.199 mm. It is basically consistent with the real data, indicating that the proposed wideband microwave holography methodology is feasible.

关键词： astronomical instrumentation methods and techniques telescopes methods:analytical atmospheric effects

Exercise and oncology:The role of physical activity in disease prevention and health promotion

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Journal of Sport and Health Science 2023年第6期12卷 651-652,F0003页

作者： zan Gao Linda Trinh School of Kinesiology University of MinnesotaMinneapolisMN 55455USA department of Kinesiology Recreationand Sport StudiesThe University of TennesseeKnoxvilleTN 37996USA Faculty of Kinesiology&Physical Education University of TorontoTorontoON M5S 2W6Canada

The field of exercise-oncology has evolved significantly over the past 30 *** studies have examined the role of structured exercise interventions—often incorporating aerobic or resistance training at m.derate-to-vigorous intensities,sometimes in conjunction with multi-modal strategies—for individuals living with and beyond cancer.

关键词： prevention promotion oncology

molecular fossils and sources of Cambrian heavy oil of Well Tadong-2 in theTarim Basin,Xinjiang,China

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Chinese Journal Of Geochemistry 2009年第3期28卷 314-319页

作者： TANG Youjun zan Ling Key Laboratory of Exploration Technologies for Oil and Gas Resources Department of Geochemistry Yangtze University Jingzhou 434023 China Faculty of Natural Resources ＆ Information Technology China University of Petroleum Beijing 102249 China

Research on the molecular fossil characteristics of heavy oil from Well Tadong-2 is of great importance to constrain the source of marine crude oils in the Tarim Basin, Xinjiang, China. The authors synthetically applied the isotope mass spectrograph, chromatography and chromatography-mass spectrography to the studies of molecular fossil characteristics of heavy oil from Well Tadong-2 in the Tarim Basin, and the results obtained revealed that heavy oil from Well Tadong-2 is characterized by high gammacerane, high C28 sterane, low rearranged sterane and high C27-triaromatic steroid, these characteristics are similar to those of Cambrian-Lower Ordovician source rocks, demonstrating that Cambrian crude oils came from Cambrian-Lower Ordovician source rocks; condensed compounds (fluoranthene, pyrene, benzo[a]anthracene, bow, benzo fluoranthene, benzopyrene) of high abundance were detected in heavy oil from Well Tadong-2, and the carbon isotopic values of whole oil are evidently heavy, all the above characteristics revealed that hydrocarbons in the crude oils became densified in response to thermal alteration.

关键词：分子化石重油井塔新疆中国 m盆地同位素质谱仪塔里木盆地

DYNAmIC TENSILE BEHAVIOR OF 5Crmnmo AT ELEVATED TEmPERATURES

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Acta metallurgica Sinica(English Letters) 2004年第4期17卷 521-527页

作者： W.Huang X.Nie X.zan Y.m.Xia department of mechanical Engineering Key Laboratory of Mechanical Behavior and Design of Materials Hefei University of Science & Technology of China 230027 Hefei ChinaDepartment of Mechanical Engineering Key Laboratory of Mechanical Behavior and Design of Materials Hefei University of Science & Technology of China 230027 Hefei ChinaDepartment of Mechanical Engineering Key Laboratory of Mechanical Behavior and Design of Materials Hefei University of Science & Technology of China 230027 Hefei ChinaDepartment of Mechanical Engineering Key Laboratory of Mechanical Behavior and Design of Materials Hefei University of Science & Technology of China 230027 Hefei China

A new experimental technique has been developed for the performance of high temperature, high-strain rate tensile experiments in the self-designed tensile impact apparatus. This technique uses rapid contact heating method to heat the specimen to the desired temperature, thus avoids a significant temperature rise in incident and transmitted bars, and at the same time it is capable of retaining a nearly homogeneous temperature field within the specimen. As an illustration of its application, the high-temperature response of the forging die steel 5Crmnmo at high strain rates has been examined. Stress-strain curves are obtained for this material at strain rates ranging from 230s-1 to 1200s-1 and at temperature ranging from 25 to 600℃, respectively. For comparison, quasi-static experiments are performed over a slightly smaller range of temperatures.

关键词： elevated temperature strain rate tensile 5Crmnmo

Feasibility of sustaining the upland conversion program by establishing a domestic carbon market

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Forestry Studies in China 2008年第4期10卷 205-211页

作者： WANG zan-xin margaret m. CALdeRON School of development Studies Yunnan University Kunming 650091 E R. China College of Forestry and Natural Resources University of the Philippines Los Banos Laguna 4031 Philippines

To sustain the upland conversion program （UCP） in China after the government compensation expires, we suggest an establishment of a domestic carbon market where forest carbon from the UCP can be traded. Taking southwest China＇s Yunnan Province as an example, we explored the feasibility of switching the UCP to a carbon offset project. The breakeven carbon price which is equivalent to the opportunity cost of agricultural cultivation was estimated and then compared with the carbon price in the international market. We found that it is feasible to change the UCP to a carbon offset project if the duration is longer than 10 years at a discount rate of 7%, and if the recent bid price （147.2 Yuan.t-1） for Chinese carbon offset project prevails. The feasibility is better for converted land with lower productivity when the project duration is given. For a given site index, the feasibility is lower as pro- ject length is reduced. The results of sensitivity analysis show that the feasibility will be enhanced as the discount rate increases; however, the changes in the price of agricultural products and the amount of sequestered carbon have insignificant effects on the choice of sites and project duration.

关键词： upland conversion program carbon sequestration domestic carbon market

基于长短时注意力机制的汉藏党政公文机器翻译

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信息技术与信息化 2025年第1期 91-94页

作者：赞拉公安见才让青海民族大学智能科学与工程学院青海西宁810007 青海民族大学藏文信息处理与软件研究所青海西宁810007

在研究汉藏党政公文机器翻译时,由于语言资源匮乏,在对党政公文领域的术语、短语及句子进行翻译时,专用术语和短句方面均暴露出错译、漏译、解释性翻译、口语化翻译以及用词不精准等问题。这些问题严重影响翻译质量,对汉藏党政公文的准... 详细信息

在研究汉藏党政公文机器翻译时,由于语言资源匮乏,在对党政公文领域的术语、短语及句子进行翻译时,专用术语和短句方面均暴露出错译、漏译、解释性翻译、口语化翻译以及用词不精准等问题。这些问题严重影响翻译质量,对汉藏党政公文的准确传递和理解起着负面作用。因此,构建高质量的汉藏党政公文语料库的同时融合和优化模型性能来提高翻译任务至关重要,文章通过融合LSTm和Transformer的长短时注意力机制的翻译模型来分别在音节、词、音节和词融合的分词方式上进行实验,实验结果表明,融合LSTm和Transformer的长短时注意力机制的翻译模型在音词融合分词方式上准确率分别在词和音节上提升了3.14%和1.92%,此外,将翻译软件与阳光翻译、班智达翻译软件在翻译任务上进行对比后得知,翻译软件在汉藏党政公文领域的翻译效果达到了预期的目标。

关键词：长短时注意力机制模型融合汉藏党政公文音词融合翻译效果