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Self-assembly and UV-curing Property of Polymerized Lyotropic Liquid Crystal Monomer of Sodium 3,4,5-tris(ll-acryloxyundecyloxy)benzoate 被引量:1
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作者 白玉勤 郭金宝 +1 位作者 王影 魏杰 《Chinese Journal of Chemical Physics》 SCIE CAS CSCD 2013年第1期95-101,I0004,共8页
A polymerized lyotropic liquid crystal monomer of sodium 3,4,5-tris(11-acryloxyundecyloxy)- benzoate was synthesized by a convenient route starting from 3,4,5-trihydroxybenzoic acid via esterification followed by et... A polymerized lyotropic liquid crystal monomer of sodium 3,4,5-tris(11-acryloxyundecyloxy)- benzoate was synthesized by a convenient route starting from 3,4,5-trihydroxybenzoic acid via esterification followed by etherification, acylation and finally neutralization. The chemi- cal structure was confirmed by Fourier transform infrared (FT-IR) and 1H nuclear magnetic resonance spectral analysis. The self-organization behavior of the monomer with deionized water in methanol at room temperature was also demonstrated. The assemblies were char- acterized by polarized optical microscope and X-ray diffraction. The results show that a solution containing 80:20 of the monomer to water was found to be able to self-organize into Lamellar (La) phase and 92:8 with inverted hexagonal (H]I) phase, which was in ac- cordance with the theoretical calculation of critical packing parameter. It suggests that the concentration of the monomer was the key factor to influence assembly structure. Addi- tionally, the acrylate conversion with different photoinitiators and nanostructure retention after polymerization were investigated. The research shows that the acrylate conversion of the monomer with Darocur2959 could reach up to 78% when irradiated by 30 mW/cm2 UV light of 365 nm for 30 min characterized by Real-time FT-IR as well as the sol-gel method. Meanwhile, the La and HII phase nanostructures were both retained after polymerization. 展开更多
关键词 Polymerized lyotropic liquid crystal self-assembly La phase HII phase UV-CURING
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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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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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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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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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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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Tunable Phase Structure of Side-chain Liquid Crystalline Polymers Enabled by Molecular Engineering of Dual Mesogenic Cores 被引量:2
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作者 Wen-Huan Yao Lan-Sheng Liu +5 位作者 Jie Zhao Yan-Xia Wang An-Zhi Ma Zheng-Rui Ma Lan-Ying Zhang Ruo-Chen Lan 《Chinese Journal of Polymer Science》 SCIE EI CAS CSCD 2024年第10期1459-1469,I0009,共12页
A series of novel side-chain liquid crystalline(SCLC)copolymers were synthesized by attaching two distinct mesogenic units,namely a chiral cholesteryl-based monomer(M1)and an achiral biphenyl-based monomer(M2),to a po... A series of novel side-chain liquid crystalline(SCLC)copolymers were synthesized by attaching two distinct mesogenic units,namely a chiral cholesteryl-based monomer(M1)and an achiral biphenyl-based monomer(M2),to a poly(3-mercaptopropylmethylsiloxane)(PMMS)backbone via thiol-ene click chemistry.The influence of side chain composition on the self-assembly behavior and phase structures of these SCLC copolymers was systematically investigated using different instrument.Results indicate that three distinct liquid crystalline phases and four unique molecular configurations were identified within the polymer series,with the emergence of the liquid crystalline phase being a synergistic outcome of the two distinct side chains.This study underscores the critical influence of side chain dimensions,rigidity,and spatial volume on the self-assembly structures and phase characteristics of liquid crystalline polymers,providing valuable insights for the rational design and development of advanced functional materials with tailored properties. 展开更多
关键词 liquid crystalline copolymers self-assembly phase structure Chiral molar ratio
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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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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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Preparation and Characterization of Titania Microspheres and Their Application in a Liquid Chromatography Stationary Phase
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作者 Jie Zhang Xiaoshu Zhu Yinping Zhang 《Journal of Crystallization Process and Technology》 2016年第3期21-28,共8页
Titania microspheres were synthesized using hydrothermal methods to exploit a new liquid chromatography stationary phase. The prepared titania microspheres were approximately 7 μm in diameter, and the particle size d... Titania microspheres were synthesized using hydrothermal methods to exploit a new liquid chromatography stationary phase. The prepared titania microspheres were approximately 7 μm in diameter, and the particle size distribution was relatively narrow and uniform. Furthermore, the average specific surface area was 276.0 m2·g·1, the average pore volume was approximately 0.25 mL·g·1, and the pore diameter was approximately 35.9 nm for sintering titania microspheres. These parameters indicate that the titania microspheres prepared for this study have excellent surface properties for chromatography. Additionally, columns filled with the titania microspheres were able to separate basic compounds, including benzene, nitrobenzene and o-nitroanisole. It could be proposed that the titania microspheres prepared for this study would be a promising stationary phase for liquid chromatography. 展开更多
关键词 Hydrothermal method Porous Materials Titania Microspheres SINTERING liquid Chromatography Stationary phase SURFACES
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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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水平井内柱状柱塞举升气液流动密封特性
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作者 白博峰 张宇豪 +3 位作者 万华旭 王予 缪云 赵昆鹏 《天然气工业》 北大核心 2026年第1期87-95,共9页
柱塞气举技术是保障非常规油气水平井生产后期井筒积液高效排液的关键手段之一,其核心机理在于利用柱塞在气液两相间形成固体密封界面,以减少气体上窜和液体滑脱,从而显著提高举升效率。当前研究对直井内柱塞举升的气液流动密封特性已... 柱塞气举技术是保障非常规油气水平井生产后期井筒积液高效排液的关键手段之一,其核心机理在于利用柱塞在气液两相间形成固体密封界面,以减少气体上窜和液体滑脱,从而显著提高举升效率。当前研究对直井内柱塞举升的气液流动密封特性已有充分认识,但对非常规水平井内气液界面动态密封机制缺乏定量描述。为此,通过数值模拟研究了0°~70°井斜角范围内柱塞举升的气液流动密封特性,重点关注了气液泄漏行为及其对携液能力的影响,最后基于两相流动力学控制方程,构建了泄漏流量预测模型,阐释了水平井柱塞气举过程中的多相流动机理。研究结果表明:①柱塞速度主导了泄漏模式,在高速条件下(>6 m/s)液膜剪切失稳是液体泄漏的主因;②液体泄漏流量随着井斜角增大呈先增大后减小的非单调变化规律;③井筒压力升高虽可抑制气体上窜,但会加剧液体的泄漏;④推导形成的理论模型量化了泄漏过程压差驱动与剪切驱动在泄漏过程中的竞争关系。结论认为:①模型揭示了井斜角对泄漏量的非单调变化规律,并构建了泄漏流量预测模型,有助于指导水平井柱塞结构设计、优化柱塞制度,提高水平井柱塞周期排液量;②揭示的动态密封机制可为水平井柱塞的密封优化与举升工艺参数设计提供理论基础,并对非常规油气藏水平井的高效排采与气田稳产增产具有重要理论指导意义。 展开更多
关键词 柱塞气举 气液泄漏 携液能力 VOF方法 定向水平井 井斜角 两相流
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基于多相质点网格法的复杂裂缝网络支撑剂运移规律模拟
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作者 王强 杨郁 +7 位作者 赵金洲 庄文龙 徐岩光 侯杰 张艺宣 胡永全 王玉丰 李小伟 《石油勘探与开发》 北大核心 2026年第1期213-222,共10页
采用三维多相质点网格方法,建立考虑复杂缝网的液-固两相流模型,同时采用物理实验数据验证模型的可靠性,在此基础上,分析影响裂缝网络中支撑剂运移规律的主要因素。研究表明:支撑剂在缝网中的运移可划分为初始充填、优势通道形成、缝网... 采用三维多相质点网格方法,建立考虑复杂缝网的液-固两相流模型,同时采用物理实验数据验证模型的可靠性,在此基础上,分析影响裂缝网络中支撑剂运移规律的主要因素。研究表明:支撑剂在缝网中的运移可划分为初始充填、优势通道形成、缝网延伸3个阶段,分别对应近井区域形成斑块状堆积、支撑剂沿主裂缝优先铺置、流体进入分支级缝提升平面铺置效果3种支撑剂运移规律。支撑剂密度越高、压裂液黏度越低、注入排量越低、支撑剂粒径越大,支撑剂在裂缝中的运移距离越短、支撑剂平面铺置系数越小,采用低密度、小粒径支撑剂与高黏度压裂液,同时适当提高压裂液注入排量可有效扩大改造范围。主裂缝-分支缝夹角越小,支撑剂在分支缝中形成的砂堤长度越大,覆盖范围越广,分布越均匀,改造效果越好;主裂缝-分支缝夹角越大,支撑剂在分支缝入口附近堆积的可能性越大,支撑剂平面铺置系数越小。 展开更多
关键词 多相质点网格法 复杂缝网 液-固两相流 支撑剂运移 压裂施工参数 影响因素
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亚硫酸钙液相氧化制备硫酸钙工艺的优化研究
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作者 林武滔 王启飞 陈成武 《湖南文理学院学报(自然科学版)》 2026年第1期39-43,共5页
本实验采用了液相氧化法,以亚硫酸钙为原料,过硫酸铵为氧化剂,在水介质中进行反应。系统地研究了反应时间、反应温度以及亚硫酸钙与过硫酸铵的摩尔比对转化过程的影响。利用X射线衍射(XRD)技术对产物进行了结构表征,并通过碘量法定量分... 本实验采用了液相氧化法,以亚硫酸钙为原料,过硫酸铵为氧化剂,在水介质中进行反应。系统地研究了反应时间、反应温度以及亚硫酸钙与过硫酸铵的摩尔比对转化过程的影响。利用X射线衍射(XRD)技术对产物进行了结构表征,并通过碘量法定量分析了亚硫酸钙的转化率。使用扫描电子显微镜(SEM)观察硫酸钙晶体形貌。实验结果表明,在最佳条件(反应温度40℃,反应时间1.5 h,亚硫酸钙与过硫酸铵的摩尔比为1:1.1)下,亚硫酸钙的转化率达97.34%。XRD分析证实了所得硫酸钙的纯度较高,SEM观察到生成的硫酸钙晶体较为均匀,且产物具有较高的单一性。液相氧化法高效实现亚硫酸钙向硫酸钙的转化,为工业固废处理提供了绿色解决方案。 展开更多
关键词 亚硫酸钙 硫酸钙 液相氧化 碘量法 过硫酸铵
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粒径对环形射流泵内固液两相流特性的影响
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作者 李晓平 蒋耀涵 +2 位作者 谈明高 吴贤芳 刘厚林 《水电能源科学》 北大核心 2026年第2期196-200,88,共6页
为探究粒径对环形射流泵输送固液两相流特性的影响,采用RANS-DEM耦合的方法对环形射流泵内固液两相流进行数值模拟,分析了颗粒粒径对环形射流泵的效率及压力比、输送单位质量颗粒能耗、颗粒运动特性与速度分布、颗粒碰撞特性与分布以及... 为探究粒径对环形射流泵输送固液两相流特性的影响,采用RANS-DEM耦合的方法对环形射流泵内固液两相流进行数值模拟,分析了颗粒粒径对环形射流泵的效率及压力比、输送单位质量颗粒能耗、颗粒运动特性与速度分布、颗粒碰撞特性与分布以及壁面磨损等的影响规律。研究结果表明,随着颗粒粒径增大,环形射流泵的效率及压力比下降,而输送能耗则增大;颗粒首次进入各部件的时间略微增加,最大增加约0.007 s,但过泵时间稍有降低,最大降低约0.004 s;颗粒加速过程减缓,颗粒最大速度先减小后升高,且波动加剧,而颗粒平均速度则逐渐提升;颗粒碰撞总次数先下降后上升,颗粒间碰撞占据主导地位。 展开更多
关键词 环形射流泵 颗粒粒径 固液两相流 RANS-DEM耦合
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负载纳米零价铁的生物炭的制备及其性质研究
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作者 孔天岐 孙佳梦 +3 位作者 刘晶 王涵 张万里 李润东 《可再生能源》 北大核心 2026年第2期143-149,共7页
为探究负载方法对负载纳米零价铁(nFe^(0))的生物炭性质的影响,文章分别通过液相还原法、溶胶凝胶法和球磨法制备了3种负载nFe^(0)的生物炭(LR-nFe^(0)/BC,SG-nFe^(0)/BC和BM-nFe^(0)/BC)。研究发现:nFe^(0)在生物炭表面呈现清晰的球状... 为探究负载方法对负载纳米零价铁(nFe^(0))的生物炭性质的影响,文章分别通过液相还原法、溶胶凝胶法和球磨法制备了3种负载nFe^(0)的生物炭(LR-nFe^(0)/BC,SG-nFe^(0)/BC和BM-nFe^(0)/BC)。研究发现:nFe^(0)在生物炭表面呈现清晰的球状,但是LR-nFe^(0)/BC和BM-nFe^(0)/BC表面的nFe^(0)分散性明显高于SG-nFe^(0)/BC;负载nFe^(0)的生物炭表面官能团丰富,具有超顺磁性;相比于常规生物炭,负载nFe^(0)的生物炭的平均孔径增大了77%~87%,电导率提高了37%~52%,pH值升至8~9。 展开更多
关键词 纳米零价铁 生物炭 液相还原法 溶胶凝胶法 球磨法
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固相萃取结合亲水相互作用色谱-串联质谱法快速测定生鲜牛乳中3种异噻唑啉酮类药物残留量
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作者 吴剑平 吴雨珊 +1 位作者 张婧 严凤 《中国乳品工业》 北大核心 2026年第1期74-80,共7页
文章建立了生鲜牛乳中3种异噻唑啉酮类药物残留量的液相色谱-串联质谱快速检测方法。试样经乙腈提取2次,合并提取液后经Waters Prime HLB小柱富集净化,洗脱液采用Waters BEH HILIC(2.1 mm×100 mm,1.7μm)亲水相互作用色谱柱分离后... 文章建立了生鲜牛乳中3种异噻唑啉酮类药物残留量的液相色谱-串联质谱快速检测方法。试样经乙腈提取2次,合并提取液后经Waters Prime HLB小柱富集净化,洗脱液采用Waters BEH HILIC(2.1 mm×100 mm,1.7μm)亲水相互作用色谱柱分离后,用串联四级杆质谱检测器分析,同位素内标法定量。结果表明,3种异噻唑啉酮药物在2.5~250μg/kg范围内线性良好(r≥0.995),检测限均可达4μg/kg,定量限均可达10μg/kg。在试样中进行3次水平添加回收试验,3种药物的添加回收率分别可达81.5%~92.9%,批内变异系数可达4.15%~10.46%,批间变异系数可达5.50%~8.97%。该方法操作简便,仪器分析时间短,方法灵敏度高,且具有较高的准确度与精密度,适用于生鲜牛乳中3种异噻唑啉酮类药物的快速检测。 展开更多
关键词 异噻唑啉酮 生鲜牛乳 固相萃取 亲水相互作用色谱 同位素内标法
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化学还原法制备高分散性超细银粉的研究
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作者 周克武 何正海 +2 位作者 童意平 金扬灯 孔欣 《电工材料》 2026年第1期25-29,共5页
采用化学还原法,通过3种不同还原剂体系(氨水-水合肼、抗坏血酸、氢氧化钠-葡萄糖)可从硝酸银溶液中制备出高分散性超细银粉。具体工艺如下:采用氨水-水合肼还原体系时,需控制反应pH处于10~10.5,且快速加入水合肼溶液,可制备出D_(50)=1... 采用化学还原法,通过3种不同还原剂体系(氨水-水合肼、抗坏血酸、氢氧化钠-葡萄糖)可从硝酸银溶液中制备出高分散性超细银粉。具体工艺如下:采用氨水-水合肼还原体系时,需控制反应pH处于10~10.5,且快速加入水合肼溶液,可制备出D_(50)=1.15μm的超细银粉;采用抗坏血酸溶液还原时,控制反应pH为6,可制备出D_(50)=1.53μm超细银粉;采用氢氧化钠-葡萄糖还原体系时,需先通过氢氧化钠与硝酸银反应生成氢氧化银晶粒,作为稳定粒径和高分散性的前驱体,再快速加入葡萄糖溶液进行反应,可制备D_(50)=0.80μm的超细银粉。 展开更多
关键词 液相还原法 沉淀还原法 水合肼 抗坏血酸 葡萄糖
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高纯硝酸银制备工艺发展及前景综述
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作者 攸骏 邓戈 +4 位作者 方德 杨孟昌 李玉东 孙应销 董竞成 《云南冶金》 2026年第1期81-86,共6页
高纯硝酸银(AgNO_(3))在电子工业、光学材料、生物医药、化学分析、纳米材料和高端涂料等领域应用广泛,其高纯度要求对提升相关产品性能和质量至关重要。综述了高纯硝酸银的主要制备工艺和发展历程,并探讨了各工艺的优缺点和改进措施,... 高纯硝酸银(AgNO_(3))在电子工业、光学材料、生物医药、化学分析、纳米材料和高端涂料等领域应用广泛,其高纯度要求对提升相关产品性能和质量至关重要。综述了高纯硝酸银的主要制备工艺和发展历程,并探讨了各工艺的优缺点和改进措施,通过对比各类工艺的优缺点,为高纯硝酸银制备工艺改进提供参考。分析了高纯硝酸银的应用领域及发展前景,指出其在新兴应用领域如纳米材料和高端电子元器件中具有广阔应用前景,高纯硝酸银的技术创新和工艺改进将向高效、节能和环保方向发展,以满足日益增长的市场需求,并在更多高科技领域发挥重要作用。 展开更多
关键词 高纯硝酸银 液相还原法 除杂 蒸发结晶
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Influence of baffle position on liquid sloshing during braking and turning of a tank truck 被引量:10
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作者 Ning KANG Kui LIU 《Journal of Zhejiang University-Science A(Applied Physics & Engineering)》 SCIE EI CAS CSCD 2010年第5期317-324,共8页
The influence of baffle position on liquid sloshing during the braking and turning of a tank truck was studied using a volume of fluid (VOF) model. The forces,their positions and weight distribution during braking and... The influence of baffle position on liquid sloshing during the braking and turning of a tank truck was studied using a volume of fluid (VOF) model. The forces,their positions and weight distribution during braking and the forces and rolling moment during turning were calculated. The reliability of the calculation method was validated by comparisons with experimental results. The results showed that during braking,liquid splashes in the tank and the maximum forces and G (the ratio of weight acting on the front axle to the rear axle) are large when A (the ratio of the arch area above the baffle to the area of cross section)≤0.1. When A≥0.2,as the position of the baffle is lowered,the maximum of Fx (the force in direction x) first decreases then increases,and the maximum of Fy (the force in direction y) and G increase. During turning,liquid splashes in the tank and the maximum forces and M (the rolling moment) are large when D (the ratio of the arch area above the baffle to the area of cross section)≤0.2. When D≥0.3,as the position of the baffle is lowered,the maximums of Fy,Fz (the force in direction z) and M increase. 展开更多
关键词 Tank truck Volume of fluid (VOF) method liquid sloshing Two phase flow BAFFLE
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