Quantitative spectroscopic analysis of heterogeneous mixtures: the correction of multiplicative effects caused by variations in physical properties of samples

Spectral measurements of complex heterogeneous types of mixture samples are often affected by significant multiplicative effects resulting from light scattering, due to physical variations (e.g. particle size and shape, sample packing and sample surface, etc.) inherent within the individual samples. Therefore, the separation of the spectral contributions due to variations in chemical compositions from those caused by physical variations is crucial to accurate quantitative spectroscopic analysis of heterogeneous samples. In this work, an improved strategy has been proposed to estimate the multiplicative parameters accounting for multiplicative effects in each measured spectrum, and hence mitigate the detrimental influence of multiplicative effects on the quantitative spectroscopic analysis of heterogeneous samples. The basic assumption of the proposed method is that light scattering due to physical variations has the same effects on the spectral contributions of each of the spectroscopically active chemical component in the same sample mixture. Based on this underlying assumption, the proposed method realizes the efficient estimation of the multiplicative parameters by solving a simple quadratic programming problem. The performance of the proposed method has been tested on two publicly available benchmark data sets (i.e. near-infrared total diffuse transmittance spectra of four-component suspension samples and near infrared spectral data of meat samples) and compared with some empirical approaches designed for the same purpose. It was found that the proposed method provided appreciable improvement in quantitative spectroscopic analysis of heterogeneous mixture samples. The study indicates that accurate quantitative spectroscopic analysis of heterogeneous mixture samples can be achieved through the combination of spectroscopic techniques with smart modeling methodology

The transition form factors and angular distributions of the Λb→Λ(1520)(→NKˉ)ℓ+ℓ−\bm{\Lambda_b\to\Lambda(1520)(\to N\bar{K})\ell^+\ell^-} decay supported by baryon spectroscopy

We calculate the weak transition form factors of the $\Lambda_b\to\Lambda(1520)$ transition, and further calculate the angular distributions of the rare decays $\Lambda_b\to\Lambda(1520)(\to N\bar{K})\ell^{+}\ell^{-}$ ($N\bar{K}=\{pK^-,n\bar{K}^0\}$) with unpolarized $\Lambda_b$ and massive leptons. The form factors are calculated by the three-body light-front quark model with the support of numerical wave functions of $\Lambda_b$ and $\Lambda(1520)$ from solving the semirelativistic potential model associated with the Gaussian expansion method. By fitting the mass spectrum of the observed single bottom and charmed baryons, the parameters of the potential model are fixed, so this strategy can avoid the uncertainties arising from the choice of a simple harmonic oscillator (SHO) wave function of the baryons. With more data accumulated in the LHCb experiment, our result can help for exploring the $\Lambda_b\to\Lambda(1520)\ell^+\ell^-$ decay and deepen our understanding on the $b\to s\ell^+\ell^-$ processes.Comment: 21 pages, 9 figures. Accepted by Phys. Rev.

Clinical observation on the treatment of glaucoma with cataract through triple surgery

AIM: To observe the therapeutic effect of triple surgery in the treatment of glaucoma with cataract at different stages.<p>METHODS: Totally 31 patients(55 eyes)with glaucoma and cataract were treated with phacoemulsification, lens implantation and trabeculectomy. Preoperation and postoperation of visual acuity, intraocular pressure, filtering bleb and postoperation complications were observed.<p>RESULTS: After 6mo postoperation, the vision was significantly improved. The intraocular pressure was controlled in normal range and filtering bleb was good. There was a little complications after operation.<p>CONCLUSION: Phacoemulsification intraocular lens implantation with anti-glaucoma establishes new aqueous humor outflow. It can effectively decrease intraocular pressure, deepen anterior chamber and improve vision, reduce all kinds of complications after simple glaucoma surgery