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Optical simulation of in-plane-switching blue phase liquid crystal display using the finite-difference time-domain method 被引量:1
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作者 窦虎 马红梅 孙玉宝 《Chinese Physics B》 SCIE EI CAS CSCD 2016年第9期117-121,共5页
The finite-difference time-domain method is used to simulate the optical characteristics of an in-plane switching blue phase liquid crystal display.Compared with the matrix optic methods and the refractive method,the ... The finite-difference time-domain method is used to simulate the optical characteristics of an in-plane switching blue phase liquid crystal display.Compared with the matrix optic methods and the refractive method,the finite-difference timedomain method,which is used to directly solve Maxwell's equations,can consider the lateral variation of the refractive index and obtain an accurate convergence effect.The simulation results show that e-rays and o-rays bend in different directions when the in-plane switching blue phase liquid crystal display is driven by the operating voltage.The finitedifference time-domain method should be used when the distribution of the liquid crystal in the liquid crystal display has a large lateral change. 展开更多
关键词 finite-difference time-domain method blue phase liquid crystal display in-plane switching convergence effect
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PEG-combined liquid phase synthesis and electrochemical properties of carbon-coated Li_3V_2(PO_4)_3 被引量:1
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作者 王任衡 李新海 +2 位作者 王志兴 郭华军 黄斌 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2015年第4期1241-1247,共7页
The carbon-coated monoclinic Li3V2(PO4)3(LVP) cathode materials were successfully synthesized by liquid phase method using PEG as reducing agent and carbon source. The effects of relative molecular mass of PEG on the ... The carbon-coated monoclinic Li3V2(PO4)3(LVP) cathode materials were successfully synthesized by liquid phase method using PEG as reducing agent and carbon source. The effects of relative molecular mass of PEG on the properties of Li3V2(PO4)3/C were evaluated by X-ray diffraction(XRD), scanning electron microscope(SEM) and electrochemical performance tests. The SEM images show that smaller size particles are obtained by adding larger and smaller PEGs. The electrochemical cycling of Li3V2(PO4)3/C prepared by both PEG200 and PEG20 k has a high initial discharge capacity of 131.1 mA·h/g at 0.1C during 3.0-4.2 V, and delivers a reversible discharge capacity of 123.6 m A·h/g over 30 cycles, which is better than that of other samples. The improvement in electrochemical performance is caused by its improved lithium ion diffusion coefficient for the macroporous morphology, which is verified by cyclic voltammetry(CV) and electrochemical impedance spectroscopy(EIS). 展开更多
关键词 lithium-ion battery lithium vanadium phosphate PEG CARBON-COATING liquid phase method
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Ni-Pt/MgAl_(2)O_(4)双金属催化剂构筑及其对不同构型烃类蒸汽重整制氢性能的影响
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作者 张菲依 王晨臣 +6 位作者 李煜 张波 陈昱江 张琛琦 郑锦泓 焦毅 鲍泽威 《化学研究与应用》 CAS 北大核心 2024年第6期1286-1294,共9页
航空煤油成分复杂,由上百种不同构型的烃类组成,然而正构烷烃、异构烷烃、环烷烃和芳香烃这几类主要组分的构型和性质差异甚大,导致其蒸汽重整反应特性存在较大差异。本论文在前期研发Ni/MgAl_(2)O_(4)基础上,引入Pt构建Ni-Pt双金属催化... 航空煤油成分复杂,由上百种不同构型的烃类组成,然而正构烷烃、异构烷烃、环烷烃和芳香烃这几类主要组分的构型和性质差异甚大,导致其蒸汽重整反应特性存在较大差异。本论文在前期研发Ni/MgAl_(2)O_(4)基础上,引入Pt构建Ni-Pt双金属催化剂,系统考察了该催化剂对不同构型组分重整反应性能的差异,并对不同构型组分在该催化剂上的重整反应路径进行了阐述。结果表明:液相还原法引人Pt能够使双金属催化剂具有合适的酸性和良好的金属Ni分散性,Ni-Pt两种金属协同效应,不仅能够提高单Ni催化剂活性,同时能够减少Ni烧结,优化催化剂稳定性;另外,不同构型组分在双金属催化剂上的重整性能具有显著差异,其中正癸烷重整的产气率以及H,选择性较为优异。不同构型烃类燃料的反应活性为:甲基环已烷>正癸烷>乙苯。由于甲基环已烷在反应过程中C-C键键能弱,易开环形成链状自由基与水发生重整反应,乙苯具有芳香烃结构且不易开环,重整反应所需能量较高。 展开更多
关键词 燃油蒸汽重整 制氢 Ni-Pt双金属催化剂 不同构型烃类 液相还原法
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基于“种子-生长”的液相法制备的CoFe_(2)O_(4)纳米颗粒及磁性能
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作者 王焱 冯治棋 +3 位作者 左显维 李昕 刘一丹 何欣 《磁性材料及器件》 CAS 2024年第3期21-26,共6页
依据不同的应用需求,实现纳米材料颗粒尺寸和形状的可控制备一直是材料制备领域研究的重点。为了研究CoFe_(2)O_(4)纳米颗粒尺寸和形状对于磁性能的影响,本文分别通过传统的液相法和基于“种子-生长”的液相法制备出了不同颗粒尺寸和形... 依据不同的应用需求,实现纳米材料颗粒尺寸和形状的可控制备一直是材料制备领域研究的重点。为了研究CoFe_(2)O_(4)纳米颗粒尺寸和形状对于磁性能的影响,本文分别通过传统的液相法和基于“种子-生长”的液相法制备出了不同颗粒尺寸和形状的CoFe_(2)O_(4)纳米颗粒并研究其磁性能。结果表明:CoFe_(2)O_(4)颗粒的尺寸和形状变化会影响纳米颗粒的分散性和矫顽力。其中,通过“种子-生长”的液相法制备的六边形CoFe_(2)O_(4)纳米颗粒的矫顽力在室温下可达383Oe,80K时高达13105Oe。 展开更多
关键词 CoFe_(2)O_(4)纳米颗粒 液相法 “种子-生长”法 形状 磁性能
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RESEARCH ON METHOD TO CALCULATE VELOCITIES OF SOLID PHASE AND LIQUID PHASE IN DEBRIS FLOW 被引量:4
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作者 陈洪凯 唐红梅 陈野鹰 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI 2006年第3期399-408,共10页
Velocities of solid phase and liquid phase in debris flow are one key problem to research on impact and abrasion mechanism of banks and control structures under action of debris flow. Debris flow was simplified as two... Velocities of solid phase and liquid phase in debris flow are one key problem to research on impact and abrasion mechanism of banks and control structures under action of debris flow. Debris flow was simplified as two-phase liquid composed of solid phase with the same diameter particles and liquid phase with the same mechanical features. Assume debris flow was one-dimension two-phase liquid moving to one direction, then general equations of velocities of solid phase and liquid phase were founded in two-phase theory. Methods to calculate average pressures, volume forces and surface forces of debris flow control volume were established. Specially, surface forces were ascertained using Bingham's rheology equation of liquid phase and Bagnold's testing results about interaction between particles of solid phase. Proportional coefficient of velocities between liquid phase and solid phase was put forward, meanwhile, divergent coefficient between theoretical velocity and real velocity of solid phase was provided too. To state succinctly before, method to calculate velocities of solid phase and liquid phase was obtained through solution to general equations. The method is suitable for both viscous debris flow and thin debris flow. Additionally, velocities every phase can be identified through analyzing deposits in-situ after occurring of debris flow. It is obvious from engineering case the result in the method is consistent to that in real-time field observation. 展开更多
关键词 debris flow two-phase fluid velocities of solid phase and liquid phase calculation method VERIFICATION
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液相法合成MOF-808催化糠醛转移加氢研究
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作者 王彤 夏晓光 左艳梅 《化学研究与应用》 CAS 北大核心 2024年第1期34-41,共8页
采用简单易行的常压液相合成法,通过调节氧氯化锆和均苯三甲酸的比例,制备得到MOF-808-x,利用X-射线衍射(XRD)、傅里叶红外光谱(FT-IR)、场发射透射电子显微镜(TEM)等对其结构、形貌进行一系列表征。以糠醛加氢为探针反应,考察了MOF-80... 采用简单易行的常压液相合成法,通过调节氧氯化锆和均苯三甲酸的比例,制备得到MOF-808-x,利用X-射线衍射(XRD)、傅里叶红外光谱(FT-IR)、场发射透射电子显微镜(TEM)等对其结构、形貌进行一系列表征。以糠醛加氢为探针反应,考察了MOF-808-x在异丙醇为氢供体体系中催化糠醛转移加氢制糠醇反应性能,并优化了反应条件。结果表明:合成催化剂适宜的原料配比可以提高反应活性。以MOF-808-1为催化剂时,在100℃反应2 h,糠醛转化率为100%,糠醇选择性>99%。 展开更多
关键词 液相法 金属有机框架 糠醇 转移加氢
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Treatment of discontinuous interface in liquid-solid forming with extended finite element method 被引量:1
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作者 周计明 齐乐华 《中国有色金属学会会刊:英文版》 CSCD 2010年第S3期911-915,共5页
Extended finite element method(XFEM) is proposed to simulate the discontinuous interface in the liquid-solid forming process.The discontinuous interface is an important phenomenon happening in the liquid-solid forming... Extended finite element method(XFEM) is proposed to simulate the discontinuous interface in the liquid-solid forming process.The discontinuous interface is an important phenomenon happening in the liquid-solid forming processes and it is difficult to be simulated accurately with conventional finite element method(CFEM) because it involves solid phase and liquid phase simultaneously.XFEM is becoming more and more popular with the need of solving the discontinuous problem happening in engineering field.The implementation method of XFEM is proposed on Abaqus code by using UEL(user element) with the flowchart.The key is to modify the element stiffness in the proposed method by using UEL on the platform of Abaqus code.In contrast to XFEM used in the simulation of solidification,the geometrical and physical properties of elements were modified at the same time in our method that is beneficial to getting smooth interface transition and precise analysis results.The analysis is simplified significantly with XFEM. 展开更多
关键词 EXTENDED FINITE ELEMENT method SOLID metal with liquid phase numerical simulation
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Preparation of Microcapsules with Liquid Droplet Coalescence Method Followed by Phase Separation 被引量:3
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作者 Yasushi Yokoyama Kiyomi Fuchigami +1 位作者 Yoshinari Taguchi Masato Tanaka 《Journal of Encapsulation and Adsorption Sciences》 2013年第3期93-97,共5页
Novel preparation method of microencapsules was developed on the basis of the liquid coalescence method followed by phase separation. Oil droplets of limonene dissolving expanded polystyrene as a shell material were f... Novel preparation method of microencapsules was developed on the basis of the liquid coalescence method followed by phase separation. Oil droplets of limonene dissolving expanded polystyrene as a shell material were forced to collide and coalesce with the Isopar oil droplets of core material in the continuous wates phase. When two kinds of oil droplets are collided and coalesced with each other, expanded polystyrene dissolved in the limonene oil may be phase-separated in the oil droplets newly formed to form the microcapsule shell, because the Isopar oil was a poor solvent for expanded polystyrene but a good solvent for the limonene oil. In the experiment, the diameter (or number) of limonene oil droplets dissolving expanded polystyrene was mainly changed, because the coalescence frequency between the droplets is strongly dependent on the number of droplets. Favorable core shell types of microcapsules with the shell thickness from 1.0 to 5.0 μm were able to be prepared under all the experimental conditions adopted here. 展开更多
关键词 Core Shell MICROCAPSULE liquid DROPLET COALESCENCE method phase Separation LIMONENE Oil liquid-liquid Dispersion
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A Stability Indicating Reverse Phase-HPLC Method Development and Validation for the Estimation of Rucaparib in Bulk and Pharmaceutical Dosage Form 被引量:1
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作者 D. Suchitra Satyanarayana Battu 《American Journal of Analytical Chemistry》 2021年第4期96-107,共12页
The research was carried out for establishing a new reverse phase-HPLC stability indicating method for the quantification of Rucaparib. The experiment was determined on Waters HPLC instrument using 996 photo-diode arr... The research was carried out for establishing a new reverse phase-HPLC stability indicating method for the quantification of Rucaparib. The experiment was determined on Waters HPLC instrument using 996 photo-diode array detector. The separation was done by using symmetry C-18 ODS (25 cm × 0.46 cm internal diameter) 5 μm analytical column containing mobile phase of Phosphate buffer (0.02 M) and methanol [65:35% v/v] adjusted pH to 4.8 by adding dilute ortho phosphoric acid. The method was run at 1 ml·min<sup>-1</sup> at 286 nm detection. The drug was eluted at 5.484 min. After developing the method, it was assured for the intended use by validation which was done according to ICH Q2B guidelines. The analytical parameters checked were linearity, accuracy, repeatability, intermediate precision, limit of detection, limit of quantitation, ruggedness and robustness. It was observed that the response of the detector was linear in the range of 6 - 14 μg/ml with correlation coefficient of 0.999. The results of all the parameters were found to be within the acceptance criteria. The stability indicating assay method was established by using the samples generated by forced degradation process. The forced degradation was carried out by subjecting the drug to acid, alkali, thermal, oxidative and photolytic degradation and the results showed that the degradation products were successfully separated from the drug. Hence, this can be applied perfectly later for the analysis of quality of the rucaparib drug. 展开更多
关键词 Rucaparib Reverse-phase High Performance liquid Chromatography method Development VALIDATION
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液-固相法合成LiMn_(0.6)Fe_(0.4)PO_(4)的性能
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作者 李亨利 徐荣益 +1 位作者 王昭沛 李意能 《电池》 CAS 北大核心 2024年第2期205-208,共4页
磷酸锰锂(LiMnPO_(4))材料的电导率低且充放电过程易发生Jahn-Teller效应,导致电化学性能不理想。通过液-固相法合成磷酸锰铁锂(LiMn_(0.6)Fe_(0.4)PO_(4))正极材料,并对晶体结构、放电曲线特性、循环性能等进行分析。Fe均匀地掺入Mn位... 磷酸锰锂(LiMnPO_(4))材料的电导率低且充放电过程易发生Jahn-Teller效应,导致电化学性能不理想。通过液-固相法合成磷酸锰铁锂(LiMn_(0.6)Fe_(0.4)PO_(4))正极材料,并对晶体结构、放电曲线特性、循环性能等进行分析。Fe均匀地掺入Mn位形成固溶体,样品的常温电化学性能得到改善。在2.0~4.3 V循环,0.1 C倍率下的放电比容量为156.5 mAh/g;以1.0 C倍率循环2000次,容量保持率超过80%。容量衰减主要源于循环过程中正极材料颗粒产生裂纹及颗粒粉化。 展开更多
关键词 锂离子电池 正极材料 磷酸锰铁锂(LiMn_(0.6)Fe_(0.4)PO_(4)) 容量衰减 掺杂 -固相法 固溶体
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固相萃取-液相色谱-串联质谱法测定污水中8 种新烟碱类农药
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作者 王海棠 李含音 +1 位作者 陆启伟 何士龙 《色谱》 CAS CSCD 北大核心 2024年第9期856-865,共10页
新烟碱类农药作为一类新型农药,由于其对非靶标生物造成生态风险而引起广泛关注。为了实现污水中痕量新烟碱类农药的快速、准确定量,本研究建立了同时检测污水中8种新烟碱类农药(呋虫胺、E-烯啶虫胺、噻虫嗪、噻虫胺、吡虫啉、氯噻啉、... 新烟碱类农药作为一类新型农药,由于其对非靶标生物造成生态风险而引起广泛关注。为了实现污水中痕量新烟碱类农药的快速、准确定量,本研究建立了同时检测污水中8种新烟碱类农药(呋虫胺、E-烯啶虫胺、噻虫嗪、噻虫胺、吡虫啉、氯噻啉、啶虫脒和噻虫啉)的固相萃取-液相色谱-串联质谱法。确定选择色谱流动相类型和质谱参数后,采用单因素法确定固相萃取(SPE)的条件:萃取柱类型为HLB(500 mg/6 mL),上样体积为500 mL,上样速度为10 mL/min,样品pH为6~8。通过优化色谱梯度洗脱程序、样品的稀释倍数并采用同位素内标定量法降低污水样品的基质效应,确定污水稀释5倍进行前处理,采用ZORBAX Eclipse Plus C18色谱柱(100 mm×21 mm,18μm),以含01%甲酸的2 mmol/L乙酸铵水溶液和甲醇为流动相进行梯度洗脱,在正离子多反应监测模式下分析10 min,用吡虫啉-d4作为同位素内标进行定量。通过响应曲面法进一步优化SPE的淋洗液及洗脱液类型和用量,确定用10%甲醇水溶液淋洗,7 mL甲醇-乙腈(1∶1,v/v)混合溶液洗脱。8种新烟碱类化合物在相应范围内线性关系良好(线性相关系数(r)均大于09990),方法检出限(MDL)为02~12 ng/L,方法定量限(MQL)为08~48 ng/L,在低、中、高3个加标水平下的加标回收率为826%~942%,RSD为39%~94%。该方法成功用于4个城镇污水处理厂进水水样的分析,8种新烟碱类农药的检出含量为ND~256 ng/L。与类似方法相比,该方法检出限低,准确度高,适用于污水中8种新烟碱类农药的痕量检测。 展开更多
关键词 液相色谱-串联质谱 固相萃取 新烟碱类农药 污水 基质效应 响应曲面法
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基于HPLC和MC-ICP-MS的植物叶绿素镁同位素测试方法
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作者 安子涵 张宏宇 +3 位作者 殷佳欣 张攀 姚敏 黄康俊 《岩矿测试》 CAS CSCD 北大核心 2024年第3期476-486,共11页
叶绿素a和叶绿素b是植物光合作用时吸收光能的主要色素,其中叶绿素b能帮助叶绿素a扩展吸收光谱促使其吸收更多光能,叶绿素a和叶绿素b比例的改变有助于植物适应光照变化。准确测定叶绿素a和叶绿素b的镁同位素值对研究叶绿素形成过程中镁... 叶绿素a和叶绿素b是植物光合作用时吸收光能的主要色素,其中叶绿素b能帮助叶绿素a扩展吸收光谱促使其吸收更多光能,叶绿素a和叶绿素b比例的改变有助于植物适应光照变化。准确测定叶绿素a和叶绿素b的镁同位素值对研究叶绿素形成过程中镁的生物合成路径等问题具有重要意义,其中将叶绿素a和叶绿素b分离并收集是使用多接收电感耦合等离子体质谱仪(MC-ICP-MS)准确测定两者镁同位素值的关键。高效液相色谱(HPLC)是分离叶绿素的常用仪器,但目前HPLC分离叶绿素的方法主要聚焦于细菌和藻类叶绿素分离。因此,需开发一套能将植物叶绿素a和叶绿素b分离的方法,且该方法分离的样品适用于MC-ICP-MS的镁同位素测定。本文基于665nm检测波长和C18色谱柱(7.6mm×250mm,5μm),以三因素三水平正交设计优化HPLC条件,分析影响样品运行因素间的关系,得出符合要求的参数条件。经过优化的HPLC方法柱温为25℃,流速为1mL/min,流动相为甲醇-丙酮(80∶20,V/V)。结果表明:通过外标法定量分析叶绿素a和叶绿素b所得标准曲线在5~50mg/L浓度范围内的相关系数均大于0.9996,检测限为0.40~1.09mg/L,定量限为1.22~3.31mg/L,相对标准偏差(RSD)小于8.10%,样品加标回收率介于91.92%~111.11%。采用该方法对样品进行分离后,再利用MC-ICP-MS对前处理后的样品进行镁同位素测定,标准-样品间插法测定的数据表明镁同位素测试结果可靠,证明本文建立的方法为植物叶绿素a和叶绿素b的分离提供了技术支撑,且分离样品可用于镁同位素测定。 展开更多
关键词 镁同位素 标准-样品间插法 高效液相色谱法 流动相 叶绿素A 叶绿素B
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Quantum Spin Liquid Phase in the Shastry–Sutherland Model Detected by an Improved Level Spectroscopic Method
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作者 Ling Wang Yalei Zhang Anders W.Sandvik 《Chinese Physics Letters》 SCIE EI CAS CSCD 2022年第7期105-116,共12页
We study the spin-1/2 two-dimensional Shastry–Sutherland spin model by exact diagonalization of clusters with periodic boundary conditions, developing an improved level spectroscopic technique using energy gaps betwe... We study the spin-1/2 two-dimensional Shastry–Sutherland spin model by exact diagonalization of clusters with periodic boundary conditions, developing an improved level spectroscopic technique using energy gaps between states with different quantum numbers. The crossing points of some of the relative(composite) gaps have much weaker finite-size drifts than the normally used gaps defined only with respect to the ground state, thus allowing precise determination of quantum critical points even with small clusters. Our results support the picture of a spin liquid phase intervening between the well-known plaquette-singlet and antiferromagnetic ground states, with phase boundaries in almost perfect agreement with a recent density matrix renormalization group study, where much larger cylindrical lattices were used [J. Yang et al., Phys. Rev. B 105, L060409(2022)]. The method of using composite low-energy gaps to reduce scaling corrections has potentially broad applications in numerical studies of quantum critical phenomena. 展开更多
关键词 red SSM Sutherland Model Detected by an Improved Level Spectroscopic method Quantum Spin liquid phase in the Shastry Model
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A Stability Indicating Reverse Phase-HPLC Method Development and Validation for the Estimation of Bimatoprost 0.3% &Timolol 0.5% Pharmaceutical Ophthalmic Dosage Form
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作者 Md. S. Amin Muhammad T. Islam 《American Journal of Analytical Chemistry》 CAS 2022年第12期506-530,共25页
The research was carried out to establish a new reverse phase-HPLC stability indicating method for quantifying Bimatoprost & Timolol in ophthalmic solution. The experiment of Bimatoprost & Timolol in ophthalmi... The research was carried out to establish a new reverse phase-HPLC stability indicating method for quantifying Bimatoprost & Timolol in ophthalmic solution. The experiment of Bimatoprost & Timolol in ophthalmic solution method development was determined on Waters HPLC instrument using a UV Detector. The separation was done by using L11, Zorbex SB phenyl (4.6 mm × 250 mm internal diameter) 5 μm analytical column, containing mobile phase of Phosphate buffer (0.02 M), methanol, and acetonitrile [50:30:20 % v/v]. The method was run at 1 ml·min<sup>-1</sup> at 210 nm for Bimatoprost and 295 nm for Timolol for detection. The drug was eluted at 10.81 min for Bimatoprost and 3.77 min for Timolol. After developing the method, it was assured for the intended use by validation, which was done according to ICH Q2B guidelines. The analytical parameters checked were Specificity/Selectivity, linearity, Range, accuracy, ruggedness, and robustness. It was observed that the response of the detector was linear in the range of 6 - 18 μg/ml with a correlation coefficient of 0.999. The results of all the parameters were found to be within the acceptance criteria. The stability-indicating assay method was established by using the samples generated by the forced degradation process. The forced degradation was carried out by subjecting the drug to acid, alkali, thermal, oxidative, and photolytic degradation, and the results showed that the degradation products were successfully separated from the drug. Hence, this can be applied perfectly later for the quantitative analysis of Bimatoprost 0.3% + Timolol 0.5% Ophthalmic Solution drugs for pharmaceutical use. Currently, there is no official method for Bimatoprost & Timolol combination products in USP or BP. Available research work related to single Bimatoprost or Timolol products was not suitable for testing Bimatoprost and Timolol combination drugs. Additionally, there is no stability-indicating method to test Bimatoprost & Timolol combination products which insist us to do research and develop a new reverse phase-HPLC indicating method which will be faster and more accurate. 展开更多
关键词 BIMATOPROST TIMOLOL Reverse-phase High Performance liquid Chromatography method Development Validation Stability Indicating
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液相沉淀法制备氧化锌-壳聚糖复合材料及其抗菌性能 被引量:1
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作者 秦广超 张宁坤 +3 位作者 汪海晨 乐力 李万园 郑会会 《中国粉体技术》 CAS CSCD 2023年第1期98-106,共9页
以硝酸锌(zinc nitrate,Zn(NO_(3))_(2))为锌源,以壳聚糖(chitosan,CS)为基底,以氢氧化钠(sodium hydroxide,NaOH)为沉淀剂,采用液相沉淀法制备氧化锌-壳聚糖(zinc oxide-chitosan,ZnO-CS)复合材料;借助扫描电镜、X射线衍射分析、热重... 以硝酸锌(zinc nitrate,Zn(NO_(3))_(2))为锌源,以壳聚糖(chitosan,CS)为基底,以氢氧化钠(sodium hydroxide,NaOH)为沉淀剂,采用液相沉淀法制备氧化锌-壳聚糖(zinc oxide-chitosan,ZnO-CS)复合材料;借助扫描电镜、X射线衍射分析、热重分析、X射线光电子能谱、红外光谱和紫外吸收光谱等手段进行表征,考察ZnO-CS复合材料的形貌、结构组成以及ZnO在CS表面的吸附情况;将ZnO-CS悬浊液涂抹在新鲜熟白米上进行ZnO-CS复合材料的抗菌性能测试。结果表明:Zn^(2+) -CS表面首先生长了一层棒状ZnO粒子膜;通过受热反应CS表面的氨基与Zn^(2+)、ZnO形成交联网络,使棒状ZnO进一步生长形成片状ZnO;CS表面的氨基所形成的交联网络吸附ZnO,得到ZnO-CS复合材料;在时间为6 d时,用ZnO-CS悬浊液处理后的新鲜熟白米没有生成菌落,在时间为12 d时菌落无明显扩散,表明ZnO-CS复合材料具有良好的抗菌作用。 展开更多
关键词 氧化锌-壳聚糖复合材料 液相沉积法 抗菌性能
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Microwave absorption properties regulation and bandwidth formula of oriented Y_(2)Fe_(17)N_(3-δ)@SiO_(2)/PU composite synthesized by reduction-diffusion method 被引量:1
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作者 Hao Wang Liang Qiao +4 位作者 Zu-Ying Zheng Hong-Bo Hao Tao Wang Zheng Yang Fa-Shen Li 《Chinese Physics B》 SCIE EI CAS CSCD 2022年第11期341-351,共11页
As concepts closely related to microwave absorption properties,impedance matching and phase matching were rarely combined with material parameters to regulate properties and explore related mechanisms.In this work,red... As concepts closely related to microwave absorption properties,impedance matching and phase matching were rarely combined with material parameters to regulate properties and explore related mechanisms.In this work,reduction–diffusion method was innovatively applied to synthesize rare earth alloy Y_(2)Fe_(17).In order to regulate the electromagnetic parameters of absorbers,the Y_(2)Fe_(17)N_(3-δ)particles were coated with silica(Y_(2)Fe_(17)N_(3-δ)@SiO_(2))and absorbers with different volume fractions were prepared.The relationship between impedance matching,matching thickness,and the strongest reflection loss peak(RLmin)was presented obviously.Compared to the microwave absorption properties of Y_(2)Fe_(17)N_(3-δ)/PU absorber,Y_(2)Fe_(17)N_(3-δ)@SiO_(2)/PU absorbers are more conducive to the realization of microwave absorption material standards which are thin thickness,light weight,strong absorbing intensity,and broad bandwidth.Based on microwave frequency bands,the microwave absorption properties of the absorbers were analyzed and the related parameters were listed.As an important parameter related to perfect matching,reflection factor(√ε_(r)/μ_(r))was discussed combined with microwave amplitude attenuation.According to the origin and mathematical model of bandwidth,the formula of EAB(RL<-10 dB)was derived and simplified.The calculated bandwidths agreed well with experimental results. 展开更多
关键词 microwave absorption rare earth alloy reduction-diffusion method Y_(2)Fe_(17)N_(3-δ)@SiO_(2) reflection factor impedance and phase matching bandwidth formula
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高温高压-酸水解-液相法测定薯类食品中的淀粉含量 被引量:2
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作者 陈清凯 汪若楠 +3 位作者 傅国斌 闻佳钰 邢丽丽 吴思远 《粮食与饲料工业》 CAS 2023年第2期62-65,共4页
以土豆为原料,采用高温高压-酸水解-液相法对土豆中的淀粉含量进行测定,以期为食品中淀粉含量的测定提供高效、准确的方法。研究结果表明,较优水解条件为:盐酸浓度3.9 mol/L,消解时间35 min,消解温度109℃;在此条件下,样品中淀粉可完全... 以土豆为原料,采用高温高压-酸水解-液相法对土豆中的淀粉含量进行测定,以期为食品中淀粉含量的测定提供高效、准确的方法。研究结果表明,较优水解条件为:盐酸浓度3.9 mol/L,消解时间35 min,消解温度109℃;在此条件下,样品中淀粉可完全水解。采用液相色谱法进行测定,结果与国标法大致相同。与常规酸水解-滴定法比较,该方法具有水解时间短,操作简便,测定结果准确,重复性好等优点,是一种可行的测定方法。 展开更多
关键词 高温高压 酸水解 液相法 淀粉
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顺式双环[3.2.0]庚-2-烯-6-酮对映异构体手性拆分及含量测定
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作者 王淑红 杨威龙 +5 位作者 赵珊 李卓玲 孙美艳 王会岩 蔡建辉 修志明 《沈阳药科大学学报》 CAS CSCD 北大核心 2023年第10期1321-1328,共8页
目的高效液相色谱法拆分顺式双环[3.2.0]庚-2-烯-6-酮对映异构体并进行含量测定,同时进行含量测定的方法学研究。方法采用硅胶表面涂覆有直链淀粉-三(S)-α-甲基苯基氨基甲酸酯手性固定相,以正己烷-异丙醇(体积比95∶5)为流动相,流速0.8... 目的高效液相色谱法拆分顺式双环[3.2.0]庚-2-烯-6-酮对映异构体并进行含量测定,同时进行含量测定的方法学研究。方法采用硅胶表面涂覆有直链淀粉-三(S)-α-甲基苯基氨基甲酸酯手性固定相,以正己烷-异丙醇(体积比95∶5)为流动相,流速0.8 mL·min^(-1),柱温25℃,检测波长210 nm,采用外标法测定顺式双环[3.2.0]庚-2-烯-6-酮对映异构体的含量,采用面积归一化法计算对映异构体超量值。结果顺式双环[3.2.0]庚-2-烯-6-酮对映异构体分离度为11.4,两个对映异构体在质量浓度2~40 mg·L^(-1)内有良好线性关系(R^(2)≥0.999),(+)-顺式双环[3.2.0]庚-2-烯-6-酮低、中、高质量浓度平均加样回收率(RSD)分别为99.16%(0.8%)、99.34%(0.8%)、100.2%(0.7%);(-)-顺式双环[3.2.0]庚-2-烯-6-酮低、中、高质量浓度平均加样回收率RSD分别为99.72%(0.9%)、100.0%(0.3%)和98.81%(0.6%)。结论该方法能够用面积归一化法准确测定顺式双环[3.2.0]庚-2-烯-6-酮对映异构体超量值,为前列腺素类药物手性中间体提供新的分离方法。 展开更多
关键词 顺式双环[3 2 0]庚-2--6- 对映异构体超量 手性固定相 高效液相色谱 面积归一化法
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Fabrication and Characterization of Au Nanoparticle-aggregated Nanowires by Using Nanomeniscus-induced Colloidal Stacking Method
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作者 Sangmin An Wonho Jhe 《Nano-Micro Letters》 SCIE EI CAS 2015年第1期27-34,共8页
We fabricate and characterize Au nanoparticle-aggregated nanowires by using the nano meniscus-induced colloidal stacking method. The Au nanoparticle solution ejects with guidance of nanopipette/quartz tuning fork-base... We fabricate and characterize Au nanoparticle-aggregated nanowires by using the nano meniscus-induced colloidal stacking method. The Au nanoparticle solution ejects with guidance of nanopipette/quartz tuning fork-based atomic force microscope in ambient conditions, and the stacking particles form Au nanoparticle-aggregated nanowire while the nozzle retracts from the surface. Their mechanical properties with relatively low elastic modulus are in situ investigated by using the same apparatus. 展开更多
关键词 Au nanoparticle-aggregated nanowire Nanomeniscus-induced colloidal stacking method Atomic force microscope liquid–solid coexistence phase
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MPS-DEM方法数值模拟超长管道固液混输流动
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作者 李仁祥 赵伟文 万德成 《计算力学学报》 CAS CSCD 北大核心 2023年第3期395-402,共8页
近些年来,深海矿产开发成为热点,其中涉及的固液混输问题逐渐引起学者的关注.如矿粒在海床上的输运,涉及水平管道的输运问题;矿粒从海床输运到海上浮式建筑物,涉及垂直管道的输运问题;矿粒在不同倾角管道内的输运,涉及倾斜管道的输运问... 近些年来,深海矿产开发成为热点,其中涉及的固液混输问题逐渐引起学者的关注.如矿粒在海床上的输运,涉及水平管道的输运问题;矿粒从海床输运到海上浮式建筑物,涉及垂直管道的输运问题;矿粒在不同倾角管道内的输运,涉及倾斜管道的输运问题.对于该类问题,由于流体和固体之间的物理差异较大,对于固液两相往往采用不同的数值处理方法.本文使用MPS-DEM耦合方法模拟管道内的固液混输运动.用MPS方法模拟管道内流体的运动,用DEM方法追踪管道内颗粒的运动.在管道的进出口使用周期性边界条件,将多段管道之间进行拼接,从而实现了对超长管道内高雷诺数的颗粒输运现象的模拟.最后,分析管道颗粒和流场的速度及粒子分布等信息,分析流动特征.得到的结果会为超长管道内固液混输现象的研究提供一些借鉴意义及参考价值. 展开更多
关键词 MPS-DEM方法 固液两相流 超长管道 周期性边界条件
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