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锂电池用嵌段共聚物电解质的研究进展
嵌段共聚物电解质 锂电池 离子电导率 形貌
2017/11/28
离子导体嵌段共聚物电解质作为一种固态锂电池导离子材料引起了人们的广泛关注。 嵌段共聚物的自组装行为为设计微观尺寸有序结构提供了一种可能。 这种有序纳米结构既保证聚合物电解质良好的机械性能,同时又拥有与其它聚合物电解质相当的离子电导率,为进一步组装高性能、易加工的锂电池器件提供了一种可能。 本文综述了聚氧化乙烯型嵌段共聚物和单离子型嵌段共聚物,并总结了近期嵌段共聚物电解质的形貌影响离子电导率的实验研...
通过共聚的方法在酚酞聚芳醚砜(PES-C)的主链上引入苯并咪唑酮和5,6-二甲基苯并咪唑酮结构,制备了一系列苯并咪唑酮和5,6-二甲基苯并咪唑酮结构含量不同的高玻璃化转变温度(Tg)聚芳醚砜共聚物。 利用核磁共振谱(NMR)、傅里叶变换红外光谱仪(FTIR)、热重分析仪(TGA)等技术手段表征了三元共聚物的结构和性能。 结果表明,聚芳醚砜共聚物为无定型结构。 聚合物具有优异的热性能,并且均呈现出单...
二阶单整过程单位根检验统计量分布与仿真研究
单整过程 单位根 DF检验 蒙特卡洛模拟
2018/11/20
利用理论证明和蒙特卡洛模拟方法，研究数据生成为二阶单整过程时，经典单位根DF检验统计量分布，并考察误用临界值时检验效果。理论推导表明，在原假设成立时，检验统计量分布在大样本下收敛到维纳过程的泛函，但与经典单位根检验统计量分布不同。模拟结果显示，虽然临界值存在明显差异，但系数检验统计量具有满意的检验效果，伪t检验统计量检验效果取决于模型设置形式。因此，经典单位根检验统计量的临界值可以检验二阶单整过程...
气相色谱测定江永香姜中有机磷农药残留
气相色谱法 有机磷农药 江永香姜 残留检测
2018/9/30
为建立气相色谱法(GC)测定江永香姜中有机磷农药残留量的分析方法,从永州市江永县采集香姜试样,将试样用含体积比为1%乙酸的乙腈溶液提取,再经无水硫酸镁和醋酸钠净化,以C18色谱柱分离待测物,基质匹配标准溶液外标法定量,最后用气相色谱法(GC)法检测香姜中有机氯农药残留,从而达到定性的效果.试验表明,6种有机磷农药在0~1 mg/L的范围内线性关系良好,相关系数均大于0.990,检出限为0.012~...
Colocalization of the Ganglioside GM1 and Cholesterol Detected by Secondary Ion Mass Spectrometry
Cholesterol G(M1) Ganglioside Lipid Bilayers Spectrometry, Mass, Secondary Ion Molecular Conformation Biological Transport Microtechnology Nanotechnology Models, Molecular
2016/5/25
The characterization of the lateral organization of components in biological membranes and the evolution of this arrangement in response to external triggers remain a major challenge. The concept of l...
Solvent-Induced Infrared Frequency Shifts in Aromatic Nitriles are Quantitatively Described by the Vibrational Stark Effect
Nitriles Spectroscopy,Fourier Transform Infrared Vibration Static Electricity Solvents
2016/5/25
The physical properties of solvents strongly affect the spectra of dissolved solutes, and this phenomenon can be exploited to gain insight into the solvent-solute interaction. The large solvatochromic...
Do Ligand Binding and Solvent Exclusion Alter the Electrostatic Character within the Oxyanion Hole of an Enzymatic Active Site
Pseudomonas putida Thiocyanates Anions Oxygen Steroid Isomerases Ligands Spectroscopy, Fourier Transform Infrared Kinetics Binding Sites Static Electricity
2016/5/24
The thousands of enzyme structures solved to date have consistently revealed that biological catalysis occurs within sequestered pockets containing complex interdigitations of polar and hydrophobic gr...
Antibody Evolution Constrains Conformational Heterogeneity by Tailoring Protein Dynamics
flexibility nonlinear spectroscopy fluorscein molecular recognition
2016/5/24
The evolution of proteins with novel function is thought to start from precursor proteins that are conformationally heterogeneous. The corresponding genes may be duplicated and then mutated to select ...
Electric Fields at the Active Site of an Enzyme:Direct Comparison of Experiment with Theory
Humans Nitriles Enzyme Inhibitors Spectrophotometry, Infrared Spectrum Analysis Circular Dichroism Electricity Protein Conformation Protein Structure,Tertiary Protein Folding
2016/5/24
The electric fields produced in folded proteins influence nearly every aspect of protein function. We present a vibrational spectroscopy technique that measures changes in electric field at a specific...
Supported Membrane Composition Analysis by Secondary Ion Mass Spectrometry with High Lateral Resolution
cryosolvents sugar glass glycerol water trytophan indole IR flourescence phosphorescence
2016/5/24
The lateral organization of lipid components within membranes is usually investigated with fluorescence microscopy, which, though highly sensitive, introduces bulky fluorophores that might alter the b...
Probing Excited-State Electron Transfer by Resonance Stark Spectroscopy:4.Mutations near BL in Photosynthetic Reaction Centers Perturb Multiple Factors that Affect BL/fBL+HL
Excited-State Electron Transfer Resonance Stark Spectroscopy Mutations near BL Photosynthetic Reaction Centers Perturb Multiple Factors BL/fBL+HL
2016/5/24
Stark spectra have been obtained in the region of absorption by the accessory bacteriochlorophylls (the B-band region around 800 nm) in Rhodobacter sphaeroides reaction centers. The Stark spectra in t...
Probing Excited-State Electron Transfer by Resonance Stark Spectroscopy:3.Theoretical Foundations and Practical Applications
contracted basis Lanczos algorithm methane vibrational spectroscopy
2016/5/24
Resonance Stark effects are nonclassical Stark effects associated with excited-state charge-transfer processes. The theory of resonance Stark effects developed in Part 2 of this series is generalized ...
FTIR and Resonance Raman Studies of Nitric Oxide Binding to H93G Cavity Mutants of Myoglobin
Animals Nitric Oxide Imidazoles Myoglobin Enzyme Inhibitors Free Radical Scavengers Spectroscopy, Fourier Transform Infrared Spectrum Analysis, Raman Binding Sites Molecular Structure
2016/5/23
Nitric oxide (NO) binds to the myoglobin (Mb) cavity mutant, H93G, forming either a five- or six-coordinate Fe-NO complex. The H93G mutation eliminates the covalent attachment between the protein and ...
Analysis of Noise for Rapid-Scan and Step-Scan Methods of FT-IR Difference spectroscopy
Noise Rapid-Scan Step-Scan Methods FT-IR Difference spectroscopy
2016/5/23
Quantitative vibrational difference spectroscopy of small signals requires techniques that minimize spectral noise. As simple modulation of the sample followed by signal demodulation is often problema...
Vibrational Stark Spectroscopy of NO Bound to Heme:Effects of Protein Electrostatic Fields on the NO Stretch Frequency
rare earth alloys X-ray diffraction crystal structure phase diagram
2016/5/23
The vibrational Stark effect measures the effect of an external electric field on the vibrational (IR) spectrum of a molecule. This technique gives quantitative information on the sensitivity of a vib...