Some ion-associated species existed possibly in NaNO3 solution were investigated via the ab-initio method. The hydrated ion parings, triple and multiple ion clusters in NaNO3 solution are all analogous to those in Mg...Some ion-associated species existed possibly in NaNO3 solution were investigated via the ab-initio method. The hydrated ion parings, triple and multiple ion clusters in NaNO3 solution are all analogous to those in Mg（NO3）2 system except that the bi-dentate structures can not be formed. Only one solvent-shared ion paring has larger v1-NO3^- frequency than the hydrated NO3^- ion. And all triple clusters with two hydrated Na^＋ ions and one NO3^- have larger v1-NO3^- frequency than the hydrated NO3^- ion. The ion association process in NaNO3 solution is predicted as free ions→solvent-separated ion pairings→solvent-shared ion pairings→solvent-shared triple ion clusters→contact triple ion clusters→contact multiple ion clusters→amorphous NaNO3, which is not analogous to that in MgSO4 but those in Mg（NO3）2 and Mg（ClO4）2 systems.展开更多
A spectrophotometric approach for the detection of non-ionic surfactant (Triton X-100) has been proposed in this paper. This method does not involve extraction of the ion-associate with harmful solvents, but employs a...A spectrophotometric approach for the detection of non-ionic surfactant (Triton X-100) has been proposed in this paper. This method does not involve extraction of the ion-associate with harmful solvents, but employs adhesion of the ion-association of potassium/non-ionic surfactants complex and tetraphenylporphyrin tetrasulfonic acid obtained by vigorous shaking. The adhered ion-associate was dissolved with water and its absorbance was measured. The sensitivity for Triton X-100 was determined to be 0.146 (expressed as absorbance of 1 mg/L solution). The adhesion tendency of ion-associate was found to be dependent on the water contact angle, which in turn was influenced by a high adhesion of the ion-associate and by low blank values. In this respect, a tetrafluo-roethylene vessel was found to be the most suitable for the detection of non-ionic surfactants. This spectrophotometrical method is simply and rapidly performed by a procedure based on mechanical shaking and can be employed to detect non-ionic surfactants containing more than 7 polyethylene oxide units.展开更多
A new resonance scattering spectral (RSS) method for the determination of human serum album (HSA) has been proposed with the resonance scattering enhanced reagent of K 3[Fe-(CN) 6]. In the medium of HCl (2.0×...A new resonance scattering spectral (RSS) method for the determination of human serum album (HSA) has been proposed with the resonance scattering enhanced reagent of K 3[Fe-(CN) 6]. In the medium of HCl (2.0×10 -3 mol/L), HSA may combine with 3- by intermolecular forces (mainly by electrostatic force) to form { 3- n-HSA m+} k nanoparticle of the ion-association complexes of HSA m+- 3- n. There is a strongest resonance scattering intensity at 351 nm, owing to the existence of the resonance scattering of the nanoparticle, 3- molecular absorption and the non-distribution of the emission intensity of Xe lamp in the range of 200-1000 nm. In addition, two resonance scattering peaks at 470 and 700 nm were observed. The HSA concentration in the range of 0-12 μg/mL is linear to the resonance scattering intensity at 351 nm. The determination limit of this method is 0.1 μg/mL HSA, about ten-fold lower than that of Coomassie brilliant blue protein assay. This method has been used for the determination of HSA in human serum and synthetic samples with satisfactory results. The mechanism of enhanced resonance scattering light, the TEM of the particle, the concepts of quasi-elastic absorption and un-elastic absorption were also discussed.展开更多
The intensity of resonance Rayleigh scattering (RRS) of Evans blue (EB) or raloxifene hydrochloride (Ralo) is very weak, but it can be enhanced significantly and a new RRS spectrum appears when both of them interact t...The intensity of resonance Rayleigh scattering (RRS) of Evans blue (EB) or raloxifene hydrochloride (Ralo) is very weak, but it can be enhanced significantly and a new RRS spectrum appears when both of them interact to form an ion-association complex in sodium acetate-hydrochloric acid buffer solution at pH 1.8. The intensity of RRS is directly proportional to the concentration of Ralo in the range of 0–8.3 μg · mL?1, and the detection limit for Ralo (σ = 3) is 18.9 ng·mL?1. The method has high sensitivity and fairly good selectivity. Based on the above evidences, a new facile method for the determination of trace amount of Ralo has been established with satisfactory results.展开更多
基金Supported by the National Natural Science Foundation of China(No.20772048)
文摘Some ion-associated species existed possibly in NaNO3 solution were investigated via the ab-initio method. The hydrated ion parings, triple and multiple ion clusters in NaNO3 solution are all analogous to those in Mg（NO3）2 system except that the bi-dentate structures can not be formed. Only one solvent-shared ion paring has larger v1-NO3^- frequency than the hydrated NO3^- ion. And all triple clusters with two hydrated Na^＋ ions and one NO3^- have larger v1-NO3^- frequency than the hydrated NO3^- ion. The ion association process in NaNO3 solution is predicted as free ions→solvent-separated ion pairings→solvent-shared ion pairings→solvent-shared triple ion clusters→contact triple ion clusters→contact multiple ion clusters→amorphous NaNO3, which is not analogous to that in MgSO4 but those in Mg（NO3）2 and Mg（ClO4）2 systems.
文摘A spectrophotometric approach for the detection of non-ionic surfactant (Triton X-100) has been proposed in this paper. This method does not involve extraction of the ion-associate with harmful solvents, but employs adhesion of the ion-association of potassium/non-ionic surfactants complex and tetraphenylporphyrin tetrasulfonic acid obtained by vigorous shaking. The adhered ion-associate was dissolved with water and its absorbance was measured. The sensitivity for Triton X-100 was determined to be 0.146 (expressed as absorbance of 1 mg/L solution). The adhesion tendency of ion-associate was found to be dependent on the water contact angle, which in turn was influenced by a high adhesion of the ion-associate and by low blank values. In this respect, a tetrafluo-roethylene vessel was found to be the most suitable for the detection of non-ionic surfactants. This spectrophotometrical method is simply and rapidly performed by a procedure based on mechanical shaking and can be employed to detect non-ionic surfactants containing more than 7 polyethylene oxide units.
文摘A new resonance scattering spectral (RSS) method for the determination of human serum album (HSA) has been proposed with the resonance scattering enhanced reagent of K 3[Fe-(CN) 6]. In the medium of HCl (2.0×10 -3 mol/L), HSA may combine with 3- by intermolecular forces (mainly by electrostatic force) to form { 3- n-HSA m+} k nanoparticle of the ion-association complexes of HSA m+- 3- n. There is a strongest resonance scattering intensity at 351 nm, owing to the existence of the resonance scattering of the nanoparticle, 3- molecular absorption and the non-distribution of the emission intensity of Xe lamp in the range of 200-1000 nm. In addition, two resonance scattering peaks at 470 and 700 nm were observed. The HSA concentration in the range of 0-12 μg/mL is linear to the resonance scattering intensity at 351 nm. The determination limit of this method is 0.1 μg/mL HSA, about ten-fold lower than that of Coomassie brilliant blue protein assay. This method has been used for the determination of HSA in human serum and synthetic samples with satisfactory results. The mechanism of enhanced resonance scattering light, the TEM of the particle, the concepts of quasi-elastic absorption and un-elastic absorption were also discussed.
文摘The intensity of resonance Rayleigh scattering (RRS) of Evans blue (EB) or raloxifene hydrochloride (Ralo) is very weak, but it can be enhanced significantly and a new RRS spectrum appears when both of them interact to form an ion-association complex in sodium acetate-hydrochloric acid buffer solution at pH 1.8. The intensity of RRS is directly proportional to the concentration of Ralo in the range of 0–8.3 μg · mL?1, and the detection limit for Ralo (σ = 3) is 18.9 ng·mL?1. The method has high sensitivity and fairly good selectivity. Based on the above evidences, a new facile method for the determination of trace amount of Ralo has been established with satisfactory results.
