Scattering Properties of Atmospheric Aerosols over Lanzhou City and Applications Using an Integrating Nephelometer

The data, measured by a three-wavelength Integrating Nephelometer over Lanzhou City during the winters of 2001/2002 and 2002/2003 respectively, have been analyzed for investigating the scattering properties of atmospheric aerosols and exploring their relationship and the status of air pollution. The aerosol particle volume distribution is inverted with the measured spectral scattering coe?cients. The results show that the daily variation of the aerosol scattering coe?cients is in a tri-peak shape. The average ratio of backscattering coe?cient to total scattering coe?cient at 550 nm is 0.158; there exists an excellent correlation between the scattering coe?cients and the concentration of PM10. The average ratio of the concentration of PM10 to the scattering coe?cients is 0.37 g m?2, which is contingent on the optical parameters of aerosol particles such as the size distribution, etc.; an algorithm is developed for inverting the volume distribution of aerosol particles by using the histogram and Monte-Carlo techniques, and the test results show that the inversion is reasonable.

Investigation of stimulated rotational Raman scattering of the high-power broadband laser with applied angular dispersion

Smoothing by spectral dispersion （SSD） leads to considerable improvement on laser-irradiation uniformity in far field for fusion lasers. Phase modulation in time and spectral angular dispersion （SAD） across the beam introduced by SSD will affect the stimulated rotational Raman scattering （SRRS） gain in the near field. This paper focuses on the influence of SAD on SRRS gain under different laser conditions. Results show that the SAD will aggravate the generation of SRRS when the laser initial additional phase is constant. On the contrary, the SAD can reduce the SRRS gain if appropriate SSD parameters are adopted when the laser initial additional phase is variable. SSD has a certain application prospect in SRRS suppression.

A Simple and Sensitive Label-free Immunoassay for Factor B Using Resonance Scattering Spectral Detection

In pH 7.2 Na2HPO4-NaH2PO4 buffer solution and in the （GABF） was combined with human factor B （BF） specifically, presence of PEG-6000, goat-anti-human factor B and aggregated to form immune complex particles that exhibited a resonance scattering （RS） peak at 400 nm. The laser scattering indicated that the average diameter of immune complex particles was 1320 nm. BF in the concentration range of 0.04 to 9.60 μg/mL was proportional to the resonance scattering intensity at 400 nm. Its regression equation was A/=33.61C ＋ 1.4, with a correlation coefficient of 0.9969, and a detection limit of 0.01 μg/mL BF. This label-free resonance scattering spectral （RSS） method has been applied to the determination of BF in serum samples, and the results were in agreement with that of the immunoturbity.

Resonance Scattering Effect of Dopamine Product Particle and Its Application to Polyphenoloxidase Activity Assay

In pH 7.2 Na2HPO4-NaH2PO4 buffer solution, polyphenoloxidase （PPO） could catalyze the oxidization of do- pamine （DA） to form polymer particles in dark-red color, which exhibited a strong resonance scattering （RS） peak at 780 nm. In the chosen conditions, as the PPO activity increased, the RS intensity at 780 nm increased linearly. The increased RS intensity （△I780nm） was linear to the PPO activity in the range of 0.10--6.0 U·mL^- 1, with a regression equation of △I780 nm = 96.6C＋ 15.1, a relative coefficient of 0.9987 and a detection limit of 0.06 U·mL^-1 PPO. The proposed method was applied to detecting PPO activity in potato sample with satisfactory results.

Resonance Scattering Detection of Trace Hg2＋ Using Aptamer-modified AuPd Nanoalloy Probe as Catalyst

The 5 nm AuPd nanoalloy in mole ratio of Au：Pd=32 ： 1 was prepared, using sodium citrate as the stabilizing agent and NaBH4 as the reductant. The AuPd nanoalloy was modified by the aptamer to prepare an aptamer- AuPd （AptAuPd） probe for resonance scattering （RS） detection of 5.（Y-1250 nmol/L Hg2＋. The AptAuPd-Hg2＋ aptamer reaction solution was filtrated by membrane, and the AptAuPd in the filtrate exhibited strong catalytic ef- fect on the slow NiP particle reaction between NiCI2 and NaHzPO2, and the NiP particles showed a RS peak at 508 nm. The RS intensity decreased when Hg2＋ concentration increased. The decreased RS intensity was linear to Hg2＋ concentration in the range of 0.5--1250 nmol/L. The RS assays were used to determine Hg2＋ in real samples, with good results.