To analyse the differential indicators of COVID-19 in severe and mild cases and to study the factors affecting the immune function of patients and the time required for oropharyngeal swabs to become negative. Age, albumin (ALB) levels, prealbumin (PAB) levels, high-sensitivity C-reactive protein (hs-CRP) levels, platelet counts, lymphocyte counts, neutrophil counts, CD3+, CD4+, CD8+ T cell counts and the time for oropharyngeal swabs to become negative were collected from 37 patients with COVID-19; the neutrophil-to-lymphocyte ratio (NLR) and platelet-to-lymphocyte ratio (PLR) were calculated as indicators of inflammation. An independent-sample t test was used to analyse differences between the severe and mild groups, and factors affecting the CD3+, CD4+ and CD8+ T cell counts and the time for the nucleic acid tests of oropharyngeal to convert to negative were identified by single-factor and multifactor analyses. Lymphocyte, ALB, PAB, CD3+, CD4+ and CD8+ T cell levels in the severe group were lower than those in the mild group, the P values were 0.048, 0.004, 0.033, 0.033, 0.015 and 0.013, respectively. The neutrophil count and PLR were higher in the severe group compared with that in the patients of mild group; the P values were all 0.000. Single-factor analysis showed that age, ALB level, PAB level, hs-CRP level, platelet count, the NLR, the PLR and the time to a negative nucleic acid test were the main factors influencing CD3+ T cells; the P values were 0.001, 0.031, 0.001, 0.010, 0.005, 0.002, 0.000 and 0.048, respectively. Age, ALB level, PAB level, hs-CRP level, platelet count, the NLR, the PLR and time to a negative nucleic acid test were the main factors influencing CD8+ T cells; the P values were 0.000, 0.012, 0.000, 0.005, 0.002, 0.004, 0.005 and 0.003, respectively. Age, PAB level, hs-CRP level, platelet count, the NLR and the PLR were the main factors influencing CD4+ T cells; the P values were 0.001, 0.006, 0.030, 0.041, 0.005 and 0.001, respectively. Age, ALB level, PAB level, hs-CRP level, platelet count, the NLR, CD3+ T cell count and CD8+ T cell count were the main factors influencing the time to a negative nucleic acid test in oropharyngeal swabs, and the P values were 0.032, 0.043, 0.013, 0.016, 0.042, 0.049, 0.048 and 0.003, respectively. Multivariate analysis showed that the PLR and platelet count were the main factors influencing CD3+ T cells. The P values were all 0.000. The PLR and platelet count were the main factors influencing CD4+ T cells. The P values were 0.000 and 0.001, respectively. The PLR and platelet count were also the main factors influencing CD8+ T cells. The P values were 0.004 and 0.001. CD8+ T cells affected the time to a negative nucleic acid test in oropharyngeal swab samples, and the P value was 0.002. There were differences in the PLR, PAB level, ALB level and T cells between the severe and mild groups. The platelet count and PLR were the main factors influencing the immune function of patients with COVID-19, and CD8+ T cells influenced the negative conversion time of the nucleic acid test in oropharyngeal swabs.

In this thesis, stable nanoMgO particles were prepared by precipitation process, using analytical pure MgCl2·6H2O and NH3·H2O as the raw materials, which MgCl2 as the source of magnesium and NH3·H2O as the precipitating agent. The dispersant of PAAS and SHMP in appropriate dosage was also needed. The nanoMgO particles were characterized by using techniques such as Infrared Spectroscopy, Absorbance Determination, Scanning Electron Microscopy and tested by Laser Particle Size Analyzer. The nanoMgO finishing agent is prepared in the condition of ultrasonic oscillation by optimized processes which involve the choosing of appropriate dispersant. Finally, the good UV protection and antibacterial silk fabrics was obtained through functional finishing by impregnating process on silk fabrics under treated by peregal-O. This work lays a foundation for the research and application of nanoscale finishing agent preparation with the low cost. The results showed that the stability of prepared nanoMgO particles is considerable, the durability of the finished fabrics is satisfactoried.

The dyeability and light fastness of natural dye (Tea polyphenols) in the presence of various percentages of Poly-N-Vinyl-2-Pyrrolidone (PVP), ZnO nanoparticles and PVP/ZnO nanocomposites were carried out in this article. These pretreatment agents were padded on functionalized silk fabrics and the modification effects were characterized by Fourier transform infrared spectroscopy and Scanning electron microscope. The dyeability, UV protection and light fastness properties were analyzed respectively. Experimental verification and theoretical analysis of silk dyeing and finishing performance with modified natural tea polyphenols dye were made.

This research work involves the dyeing of silk fabrics with cochineal inset, Safflower yellow, gardenia blue, three kinds of natural dyes. Then, UV protection performance was analyzed. The results show that the fashion color that turquosice has been acquired through changing the proportion of each natural dyestuff in combination dyeing, simultaneously there will be a certain influence on the movement comfort performance.

The environmentally friendly composite of poly (vinyl alcohol) (PVA) and shortcut grass were prepared by hot-pressing method. First, dry grass was cut into 1.5 cm long segments. Then, shortcut grass was mixed with PVA by using water as medium. The mixed uniformly raw materials were hot-pressed at different temperatures for different times. The effects of raw material ratio, hot-pressing temperature and hot-pressing temperature on composites performance were studied. Results showed that composites tensile strength increases with the increase of PVA content. Tensile strength reaches 3.59 MPa at 50% of PVA content. The tensile fracture stretch increases with PVA content and reaches 25.28% when PVA content is 50%. The tensile strength first increases and then decreases with the increase of hot-pressing temperature and hot-pressing temperature. The hardness of composite is uneven. Hardness at 20% of PVA content is lower slightly than that at other PVA contents.