The adsorption behavior of butyl xanthate on the surface of lead oxide was investigated using continuous online in situ attenuated total reflectance Fourier transform infrared(ATR-FTIR) spectroscopy technique and tw...The adsorption behavior of butyl xanthate on the surface of lead oxide was investigated using continuous online in situ attenuated total reflectance Fourier transform infrared(ATR-FTIR) spectroscopy technique and two dimensional(2D) correlation analysis.The adsorbed layer studied was prepared by coating α-PbO particles onto the surfaces of the ZnSe crystal.The appearance of spectral peaks at 1203 cm^-1,1033 cm^-1 and their red shift indicated the formation and aggregation of xanthate at the surface of α-PbO.According to 1R intensity changes after rinsing with deionized water and a NaOH solution,the adsorption was proved to be a chemisorption type.The competition between xanthate and OH^- for the surfaces leads to desorption of xanthate at higher pH.The technique of 2D correlation ATR-FTIR spectroscopy was used to evaluate the changing order of spectral intensities in the adsorption process,and the results indicated that xanthate micelles were formed at the surfaces.The adsorption kinetics of butyl xanthate was found to be a pseudo-second-order reaction model and the adsorption capacity of butyl xanthate at α-PbO was as high as 281 mg g^-1 after 150 min.展开更多
The copper complexing of dissolved organic matter released from hydrochar(HDOM)affects the former’s environmental behavior.In this study,how hydrothermal temperatures(180,220 and 260℃)influence the molecular-level c...The copper complexing of dissolved organic matter released from hydrochar(HDOM)affects the former’s environmental behavior.In this study,how hydrothermal temperatures(180,220 and 260℃)influence the molecular-level constitutions and Cu(II)binding features of HDOM were elucidated via fourier transform ion cyclotron resonance mass spectrometry and multi-spectroscopic analysis.The findings demonstrated that the almost HDOM molecules had the traits of lower polarity and higher hydrophobicity.As the hydrothermal temperature increased,the molecules with particularly high relative strength gradually disappeared,average molecular weight,percentages of CHON and aliphatic compounds of HDOM reduced while the percentages of CHO and aromatic compounds increased.In general,the fluorescence quenching of Cu(II)weakened as hydrothermal temperature rose and the Cu(II)binding stability constants of fluorophores in HDOM were 4.50–5.31.In addition,the Cu(II) binding order of fluorophores in HDOM showed temperature heterogeneities, andpolysaccharides or aromatic rings of non-fluorescent substances had the fastest responsesto Cu(II) binding. Generally, fluorescent components tend to bind Cu(II) at relatively traceconcentrations (0–40 μmol/L), whereas non-fluorescent substances tend to the bind Cu(II)at relatively higher concentrations (50–100 μmol/L). This study contributed to the predictionof the potential environmental behaviors and risks of Cu(II) at the molecular level afterhydrochar application.展开更多
Liquid state methanol and ethanol under different temperatures have been investigated by FT-NIR(Fourier transform nearinfrared) spectroscopy,generalized two-dimensional(2D) correlation spectroscopy,and PCA(principal c...Liquid state methanol and ethanol under different temperatures have been investigated by FT-NIR(Fourier transform nearinfrared) spectroscopy,generalized two-dimensional(2D) correlation spectroscopy,and PCA(principal component analysis) . First,the FT-NIR spectra were measured over a temperature range of 30-64(or 30-71) °C,and then the 2D correlation spectra were computed.Combining near-infrared spectroscopy,generalized 2D correlation spectroscopy,and references,we analyzed the molecular structures(especially the hydrogen bond) of methanol and ethanol,and performed the NIR band assignments. The PCA method was employed to verify the results of the 2D analysis.This study will be helpful to the understanding of these reagents.展开更多
The generalized two-dimensional correlation analysis based on time-resolved light scattering patterns (2D TRLS) has been employed to study the phase separation process of an epoxy-amine-polyethersulfone blend in whi...The generalized two-dimensional correlation analysis based on time-resolved light scattering patterns (2D TRLS) has been employed to study the phase separation process of an epoxy-amine-polyethersulfone blend in which the secondary phase separation takes place. The results of the 2D TRLS provided more detailed information that was not readily observed in the 1D TRLS patterns. (i) During the first process of phase separation, the sequential order of coarsening in size of the domains among the larger and smaller ones has been reversed between the diffusion regime and the hydrodynamic regime. (ii) The change of the larger domains in size, due to the hydrodynamic flow in the late stage of the first phase separation process, keeps on taking place earlier than that of the new domains appeared in the secondary phase separation process. (iii) During the secondary phase separation process the size growth of the smaller domains takes place earlier than that of the larger ones, probably due to the assumption that the coarsening mode could decrease the interface tension more quickly.展开更多
This paper demonstrates the application of step-scan phase modulation Fourier transform infrared photoacoustic spectroscopy(FTIR-PAS) in non-destructively depth profiling of styrene-butadiene-styrene block copolymer/p...This paper demonstrates the application of step-scan phase modulation Fourier transform infrared photoacoustic spectroscopy(FTIR-PAS) in non-destructively depth profiling of styrene-butadiene-styrene block copolymer/polyethylene terephthalate(SBS/PET) layered materials.The surface thicknesses of three layered samples were determined to be 1.2,4.3 and 9.4μm by using phase difference analysis,overcoming the spatial detection limits of FTIR.Combined with generalized two-dimensional(G2D) FTIR correlation analysis,the spatial origins of peaks in the SBS/PET spectrum are identified with those having overlapping peaks between different layers are resolved.展开更多
The effect of crystallization conditions of poly(butylene succinate)(PBS) component on the crystallization of poly(tetramethylene oxide)(PTMO) component in their segment block copolymer, with a higher PTMO content(PTM...The effect of crystallization conditions of poly(butylene succinate)(PBS) component on the crystallization of poly(tetramethylene oxide)(PTMO) component in their segment block copolymer, with a higher PTMO content(PTMO mass fraction is 67%), was investigated by DSC and temperature-dependent FTIR. It is found that the isothermal crystallization time(tIC) of PBS has an effect on the crystallization behavior of PTMO component. Perturbation correlation move-window two-dimensional(PCMW2 D) correlation analysis and generalized 2 D correlation analysis(2 DIR) were performed to explore the origin of this phenomenon. The PCMW2 D and 2 DIR results show that the correlation intensity peak observed at around 20 ℃ for PTMO is due to the PTMO chains movements forced by the PBS chains folded movements. If tIC of PBS at temperature of 20 ℃ is prolonged, more PTMO components are incorporated in the region between PBS lamellae and the peak at-7.6 ℃(belonging to less-constricted PTMO chains) changes smaller and even disappears, while the peak at-16.3 ℃ belonging to more-constricted PTMO chains gets bigger. A crystallization model was also established in this study. The results of tensile testing showed that tensile strength slightly increased and elongation at break decreased with increasing heat treatment time at 40 ℃.展开更多
旨在建立基于二维相关红外光谱(2D IR spectra)的分析技术,以进行中药中是否掺杂化学药物的判别。以减肥药盐酸芬氟拉明(fenfluramine hydrochloride,FH)、盐酸西布曲明(sibutramine hydrochloride,SH)为待检化合物,确定二者同步相关谱...旨在建立基于二维相关红外光谱(2D IR spectra)的分析技术,以进行中药中是否掺杂化学药物的判别。以减肥药盐酸芬氟拉明(fenfluramine hydrochloride,FH)、盐酸西布曲明(sibutramine hydrochloride,SH)为待检化合物,确定二者同步相关谱中的特征相关峰。首先通过比较掺杂中药与盐酸芬氟拉明的同步谱中特征相关峰的相似性,初步对掺杂化合物盐酸芬氟拉明进行判定,而后利用掺杂中药异步谱能确认相关峰来源的特性,进一步确证盐酸芬氟拉明的存在;此外,根据掺杂中药同步谱中未出现与盐酸西布曲明同步谱相似的特征相关峰,可以直接判别其中未掺杂盐酸西布曲明。实验所建立的方法无需样品分离,速度快,成本低,为快速简便地进行复杂体系中是否存在化学药物的判别提供了一种新的可能的方法。展开更多
目的:分析1型糖尿病肾病(diabetic nephropathy,DN)与胰岛素抵抗的关系.方法:采用1∶1随机对照病例临床研究方法,研究对象无其他病理因素.其中,糖尿病肾病患者40例,同龄正常对照组40例.分别采集各个研究对象的血浆,Western blot检测胰...目的:分析1型糖尿病肾病(diabetic nephropathy,DN)与胰岛素抵抗的关系.方法:采用1∶1随机对照病例临床研究方法,研究对象无其他病理因素.其中,糖尿病肾病患者40例,同龄正常对照组40例.分别采集各个研究对象的血浆,Western blot检测胰岛素受体底物(insulin receptor substrate,IRS)-2、p-I R S-2和A K T、p-A K T的蛋白表达水平,并采用统计学方法分析尿蛋白含量与胰岛素信号通路相关蛋白以及胰岛素抵抗指数(homeostasis model assessment-insulin resistance,HOMA-IR)和胰岛素敏感指数(homeostasis model assessment-insulin sensitive index,HOMAISI)的相关性.结果:正常对照组血浆中p-IRS-2/IRS-2的水平比糖尿病肾病组高,差异有统计学意义(P<0.05).正常对照组血浆中p-AKT/AKT的水平也比糖尿病肾病组高,差异有统计学意义(P<0.05).通过相关性分析可知,患者尿蛋白含量、肾血流量(renal blood flow,RBF)、肾小球滤过率(glomerular filtration rate,GFR)与HOMA-IR呈正相关(P<0.05),而与HOMA-ISI呈负相关(P<0.05),与胰岛功能(homeostasis model assessment-pancreatic beta-cell function,HOMA-β%)也呈负相关(P<0.05).结论:胰岛素信号通路中p-IRS-2/IRS-2和p-AKT/AKT的比值在糖尿病肾病患者中明显下降,且患者尿蛋白含量、RBF、GFR与HOMA-IR、HOMA-ISI和HOMA-β%有相关性.说明HOMA-IR的增加和胰岛素敏感性的降低以及胰岛素信号通路受阻很可能是1型糖尿病肾病发病的重要原因,为1型糖尿病肾病的治疗提供了新的思路.展开更多
基金supported by the National Nature Science Foundation of China(Nos.51274104,50874052)National Key Basic Research Program of China(973,No.2011CB933700)
文摘The adsorption behavior of butyl xanthate on the surface of lead oxide was investigated using continuous online in situ attenuated total reflectance Fourier transform infrared(ATR-FTIR) spectroscopy technique and two dimensional(2D) correlation analysis.The adsorbed layer studied was prepared by coating α-PbO particles onto the surfaces of the ZnSe crystal.The appearance of spectral peaks at 1203 cm^-1,1033 cm^-1 and their red shift indicated the formation and aggregation of xanthate at the surface of α-PbO.According to 1R intensity changes after rinsing with deionized water and a NaOH solution,the adsorption was proved to be a chemisorption type.The competition between xanthate and OH^- for the surfaces leads to desorption of xanthate at higher pH.The technique of 2D correlation ATR-FTIR spectroscopy was used to evaluate the changing order of spectral intensities in the adsorption process,and the results indicated that xanthate micelles were formed at the surfaces.The adsorption kinetics of butyl xanthate was found to be a pseudo-second-order reaction model and the adsorption capacity of butyl xanthate at α-PbO was as high as 281 mg g^-1 after 150 min.
基金supported by the National Natural Science Foundation of China(No.42307090)the Open Subject from State Environmental Protection Key Laboratory of Aquatic Ecosystem Health in theMiddle and Lower Reaches of Yangtze River(No.AEHKF2023008).
文摘The copper complexing of dissolved organic matter released from hydrochar(HDOM)affects the former’s environmental behavior.In this study,how hydrothermal temperatures(180,220 and 260℃)influence the molecular-level constitutions and Cu(II)binding features of HDOM were elucidated via fourier transform ion cyclotron resonance mass spectrometry and multi-spectroscopic analysis.The findings demonstrated that the almost HDOM molecules had the traits of lower polarity and higher hydrophobicity.As the hydrothermal temperature increased,the molecules with particularly high relative strength gradually disappeared,average molecular weight,percentages of CHON and aliphatic compounds of HDOM reduced while the percentages of CHO and aromatic compounds increased.In general,the fluorescence quenching of Cu(II)weakened as hydrothermal temperature rose and the Cu(II)binding stability constants of fluorophores in HDOM were 4.50–5.31.In addition,the Cu(II) binding order of fluorophores in HDOM showed temperature heterogeneities, andpolysaccharides or aromatic rings of non-fluorescent substances had the fastest responsesto Cu(II) binding. Generally, fluorescent components tend to bind Cu(II) at relatively traceconcentrations (0–40 μmol/L), whereas non-fluorescent substances tend to the bind Cu(II)at relatively higher concentrations (50–100 μmol/L). This study contributed to the predictionof the potential environmental behaviors and risks of Cu(II) at the molecular level afterhydrochar application.
基金supported by the Medical Scientific Research Foundation of Guangdong Province,China(B2009043)
文摘Liquid state methanol and ethanol under different temperatures have been investigated by FT-NIR(Fourier transform nearinfrared) spectroscopy,generalized two-dimensional(2D) correlation spectroscopy,and PCA(principal component analysis) . First,the FT-NIR spectra were measured over a temperature range of 30-64(or 30-71) °C,and then the 2D correlation spectra were computed.Combining near-infrared spectroscopy,generalized 2D correlation spectroscopy,and references,we analyzed the molecular structures(especially the hydrogen bond) of methanol and ethanol,and performed the NIR band assignments. The PCA method was employed to verify the results of the 2D analysis.This study will be helpful to the understanding of these reagents.
基金supported by the National Natural Science of Foundation of China(NSFC)(Nos.20674014, 20425415,20274010,50103003,20221402)
文摘The generalized two-dimensional correlation analysis based on time-resolved light scattering patterns (2D TRLS) has been employed to study the phase separation process of an epoxy-amine-polyethersulfone blend in which the secondary phase separation takes place. The results of the 2D TRLS provided more detailed information that was not readily observed in the 1D TRLS patterns. (i) During the first process of phase separation, the sequential order of coarsening in size of the domains among the larger and smaller ones has been reversed between the diffusion regime and the hydrodynamic regime. (ii) The change of the larger domains in size, due to the hydrodynamic flow in the late stage of the first phase separation process, keeps on taking place earlier than that of the new domains appeared in the secondary phase separation process. (iii) During the secondary phase separation process the size growth of the smaller domains takes place earlier than that of the larger ones, probably due to the assumption that the coarsening mode could decrease the interface tension more quickly.
基金support from the Young Scholars' Research Funds of Beijing University of Chemical Technology(QN0728)
文摘This paper demonstrates the application of step-scan phase modulation Fourier transform infrared photoacoustic spectroscopy(FTIR-PAS) in non-destructively depth profiling of styrene-butadiene-styrene block copolymer/polyethylene terephthalate(SBS/PET) layered materials.The surface thicknesses of three layered samples were determined to be 1.2,4.3 and 9.4μm by using phase difference analysis,overcoming the spatial detection limits of FTIR.Combined with generalized two-dimensional(G2D) FTIR correlation analysis,the spatial origins of peaks in the SBS/PET spectrum are identified with those having overlapping peaks between different layers are resolved.
基金Funded by the Science and Technology Program of Sichuan,China(No.2016FZ0033)the Science and Technology Program of Sichuan Luzhou,China(No.2016-S-63(1/3)
文摘The effect of crystallization conditions of poly(butylene succinate)(PBS) component on the crystallization of poly(tetramethylene oxide)(PTMO) component in their segment block copolymer, with a higher PTMO content(PTMO mass fraction is 67%), was investigated by DSC and temperature-dependent FTIR. It is found that the isothermal crystallization time(tIC) of PBS has an effect on the crystallization behavior of PTMO component. Perturbation correlation move-window two-dimensional(PCMW2 D) correlation analysis and generalized 2 D correlation analysis(2 DIR) were performed to explore the origin of this phenomenon. The PCMW2 D and 2 DIR results show that the correlation intensity peak observed at around 20 ℃ for PTMO is due to the PTMO chains movements forced by the PBS chains folded movements. If tIC of PBS at temperature of 20 ℃ is prolonged, more PTMO components are incorporated in the region between PBS lamellae and the peak at-7.6 ℃(belonging to less-constricted PTMO chains) changes smaller and even disappears, while the peak at-16.3 ℃ belonging to more-constricted PTMO chains gets bigger. A crystallization model was also established in this study. The results of tensile testing showed that tensile strength slightly increased and elongation at break decreased with increasing heat treatment time at 40 ℃.
文摘旨在建立基于二维相关红外光谱(2D IR spectra)的分析技术,以进行中药中是否掺杂化学药物的判别。以减肥药盐酸芬氟拉明(fenfluramine hydrochloride,FH)、盐酸西布曲明(sibutramine hydrochloride,SH)为待检化合物,确定二者同步相关谱中的特征相关峰。首先通过比较掺杂中药与盐酸芬氟拉明的同步谱中特征相关峰的相似性,初步对掺杂化合物盐酸芬氟拉明进行判定,而后利用掺杂中药异步谱能确认相关峰来源的特性,进一步确证盐酸芬氟拉明的存在;此外,根据掺杂中药同步谱中未出现与盐酸西布曲明同步谱相似的特征相关峰,可以直接判别其中未掺杂盐酸西布曲明。实验所建立的方法无需样品分离,速度快,成本低,为快速简便地进行复杂体系中是否存在化学药物的判别提供了一种新的可能的方法。
文摘目的:分析1型糖尿病肾病(diabetic nephropathy,DN)与胰岛素抵抗的关系.方法:采用1∶1随机对照病例临床研究方法,研究对象无其他病理因素.其中,糖尿病肾病患者40例,同龄正常对照组40例.分别采集各个研究对象的血浆,Western blot检测胰岛素受体底物(insulin receptor substrate,IRS)-2、p-I R S-2和A K T、p-A K T的蛋白表达水平,并采用统计学方法分析尿蛋白含量与胰岛素信号通路相关蛋白以及胰岛素抵抗指数(homeostasis model assessment-insulin resistance,HOMA-IR)和胰岛素敏感指数(homeostasis model assessment-insulin sensitive index,HOMAISI)的相关性.结果:正常对照组血浆中p-IRS-2/IRS-2的水平比糖尿病肾病组高,差异有统计学意义(P<0.05).正常对照组血浆中p-AKT/AKT的水平也比糖尿病肾病组高,差异有统计学意义(P<0.05).通过相关性分析可知,患者尿蛋白含量、肾血流量(renal blood flow,RBF)、肾小球滤过率(glomerular filtration rate,GFR)与HOMA-IR呈正相关(P<0.05),而与HOMA-ISI呈负相关(P<0.05),与胰岛功能(homeostasis model assessment-pancreatic beta-cell function,HOMA-β%)也呈负相关(P<0.05).结论:胰岛素信号通路中p-IRS-2/IRS-2和p-AKT/AKT的比值在糖尿病肾病患者中明显下降,且患者尿蛋白含量、RBF、GFR与HOMA-IR、HOMA-ISI和HOMA-β%有相关性.说明HOMA-IR的增加和胰岛素敏感性的降低以及胰岛素信号通路受阻很可能是1型糖尿病肾病发病的重要原因,为1型糖尿病肾病的治疗提供了新的思路.
基金the National Natural Science Foundational of China(21071099)the Innovation Projects of Department of Education of Guangdong Province(2014KTSCX169)the Scientific Research project of Shaoguan University(S201501028)