Abstract Ten 8‐(3,3‐dimethylallyl)‐substituted flavonoid glycosides, including the four new flavonol glycosides 1 and 3 – 5 and the new flavanonol glycoside 2 , besides five known flavonol glycosides, were isolated from the aerial parts of Epimedium koreanum Nakai . Their structures were determined by spectroscopic methods, including UV, IR, 1D‐ and 2D‐NMR, ESI‐MS n , HR‐ESI‐MS, and circular dichroism (CD) experiments.
Background: COVID-19 is a deadly infectious disease that dramatically affects the safety of hospital professionals. Their knowledge, risk perception, and depression levels towards COVID-19 need to be understood.
Purpose: This study aimed to compare the differences in knowledge, risk perceptions, and depression related to COVID-19 between nurses and other professionals in hospital settings.
Methods: A cross-sectional survey was conducted in Nanjing, China at the beginning of the COVID-19 pandemic with four standardized questionnaires, including (a) demographic data, (b) knowledge about COVID-19, (c) risk perceptions, and (d) depression. Data from the two groups of participants were analyzed by Chi-square tests, correlations, and t-tests.
Results: The mean correct answer rate of knowledge for nurses was 76.42%, and for other professionals was 73.94%. T-tests indicated significant differences in total mean knowledge score and mean scores in four out of five subscale scores (p<.05). All significant differences in scores showed that nurses' knowledge was higher than other professionals, except one subscale score, which revealed that nurses' knowledge of pets could spread COVID-19 was lower than other professionals. The highest perceived risk scores in both groups were contracting influenza. The second highest was scores on COVID-19 and H1N 1 the third. T-tests indicated significant differences between these two groups in scores of contracting these three infectious diseases, with nurses higher than other professionals (p<.001). T-test also showed that the depression of nurses was higher than other professionals (p<.000). Positive relationships existed between risk perceptions and depression (p<.001).
Conclusions: More education is needed to improve hospital professionals' knowledge of COVID-19. Since nurses' risk perceptions of contracting COVID-19 and dying from this deadly infection were higher than other professionals; further studies might help researchers understand the underlying reasons better. Hospital leaders should pay attention to workers' mental health and initiate proper strategies to reduce their depression related to COVID-19. Further investigation is needed since few publications mention the relationship between the perceived risk of hospital professionals and home and food accidents.
The innocent acquirement in commercial law is only applied to commercial dealing. The real right includes right of ownership, mortgage, legal mortgage, right of retention, etc. There are many defects in the innocent acquirement system in our active civil law. We should use that in German commercial law for reference and perfect it.
A series of damping composites containing polyurethane/poly (butyl methacrylate) (PU/PBMA) as the polymer matrix and graphene nanoplates (GNP) or amino-functionalized graphene nanoplates (NGNP) as a modifier was successfully synthesized through in situ polymerization. The chemical structure, microphase configuration, damping properties, and thermal stability of the GNP–PU/PBMA and NGNP–PU/PBMA composites were evaluated. Fourier-transform infrared and X-ray photoelectron spectroscopic studies revealed that the amino (–NH 2 ) groups on the NGNP surface presumably reacted with the isocyanate (R–N = C = O) groups of the polymer matrix. This led to robust bonding between the NGNP and the hard segments in PU, resulting in an NGNP/polymer-matrix compatibility superior to that of GNP–PU/PBMA. Structural investigations based on scanning electron microscopy and atomic force microscopy revealed dispersion-state-related differences between the GNP and NGNP in the PU/PBMA matrix; the amino-functionalized GNP were more uniformly dispersed in the polymer matrix than their unmodified counterparts, and microphase separation between the hard and soft segments intensified in NGNP–PU/PBMA, resulting in a greater degree of phase separation, as confirmed by small-angle X-ray scattering analysis. Dynamic mechanical analysis (DMA) revealed that the maximum damping peak (tan δ max ) of the composite with 0.7 wt.% NGNP was 22.7% higher than that of pristine PU/PBMA. Additionally, a large independent damping peak appeared in the DMA curve of 0.7 wt.% NGNP–PU/PBMA in the high-temperature range, indicating broadening of the damping temperature range. Moreover, the NGNP incorporation effectively improved the thermal stability of the composite. Overall, this study demonstrates the viability of realizing PU-based materials with excellent thermodynamic and damping properties by incorporating amino-bearing NGNP.
According to the characteristic of sewage from MDF plant——high CODcr and high SS,the coagulation process was chosen as pre-treatment method,and PAC,PAFC,PFS,FeCl_3 were selected respectively as coagulant and PAM as the coagulant additive.The result showed the treatment effect of PAFC or PFS was better than that of other coagulants when adding inorganic coagulant only,and the removal rate was about 55%. Combined with PAM,PAFC or PFS had improved effect.The best treatment effect was obtained under the conditions of adding 1.0g/L of PFS combined with 10mg/L of PAM,and the removal rate could reach 75%with the cost of treatment being 1.8yuan per ton of wastewater.
'/%3e%3cuse xlink:href='%23a' transform='rotate(23.036 .093 25.536)'/%3e%3cuse xlink:href='%23a' transform='rotate(45.87 1.273 16.18)'/%3e%3cuse xlink:href='%23a' transform='rotate(69.945 .996 12.078)'/%3e%3cuse xlink:href='%23a' transform='rotate(20.66 -19.689 31.932)'/%3e%3c/svg%3e)