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Contact sampling has an advantage over the low shear stress cases for particle liberation from the smooth surfaces. Aerodynamic particle resuspension rates increase with the wall shear stress. It shows better results for rough and fibrous surfaces than contact removal for tested analytes.Synthetic cathinones are a class of new psychoactive substances (NPS), an emerging group of analogues to traditional illicit drugs which are functionalized to circumvent legal regulations. The analytical investigation of NPS by traditional methods, such as gas chromatography-mass spectrometry (GC-MS), is challenging because newly emerging NPS may not yet appear in spectral libraries and because of the inability to determine certain positional isomers. Low-field or "benchtop" proton nuclear magnetic resonance spectroscopy (NMR) is an alternative that provides significant qualitative information but is particularly susceptible to matrix interferences. To this end, the development of a Sequential Injection Analysis (SIA) method which uses solid-phase extraction (SPE) to remove interfering matrix components prior to NMR determination is described. Factors including the type of SPE sorbent, column dimensions, and sample loading and elution conditions were examined. Several cathinone simulants (primary, secondary, and tertiary amines), "DEA exempt" cathinone standards, as well as authentic case samples were studied. The selectivity of the SIA-NMR-UV method was investigated against a broad range of "cutting agents" and was found to successfully remove all compounds tested with the exception of other basic drugs (e.g., acetaminophen). The limit of detection and reproducibility of the method were optimized using a Plackett-Burman screening design and Sequential Simplex optimization. Using a UV detector for dual (in series) quantification, the multivariate-optimized method produced a method limit of detection (3σ) for the cathinone simulant Phenylpropanolamine (PPA) of 23 μmol L-1, and a calibration model, in terms of UV peak area, of Area = 0.19 [PPA, mmol L-1] - 0.04. The optimized method generated ~2 mL of waste per day, and had a footprint of ~1 m2 Finally, the multivariate-optimized SIA-NMR-UV method was successfully applied to several more case samples and the cathinones were definitively identified.Colon and gastric cancers are the widespread benign types of cancers which are synchronous and metachronous neoplasms. In terms of the progression and progress of the disease, metabolic processes and differentiation in protein structures have an important role in for treatment of the disease. In this study we proposed to investigate the metabolic process and the differentiation of protein secondary structure among colon and gastric cancer as well as healthy controls using biochemistry and Fourier Transform InfraRed spectroscopy (FTIR) methods. For this purpose, we measured blood serum of 133 patients, which were conducted upon oncology department (45 colon cancer, 45 gastric cancer and 43 control individuals). The obtained spectroscopic results and biochemical assays showed significant reduction in the amount of functional groups in cancer groups contrary with total protein measurements and structure of protein differences between colon and gastric cancers. Differentiations were visible in serum levels of CEA, CA-125, CA-15-3, CA-19-9 AFP (Alpha fetoprotein) of gastric and colon cancer patients as well as in amide III and secondly described amide I regions. Our findings suggest that amide I bonds in colon cancer cells can be helpful in diagnosis of colon cancer. Indeed, our results showed that metabolic processes were higher in gastric cancer group than in colon cancer. Hence, FTIR spectroscopy and curve-fitting analysis of amide I profile can be successfully applied as tools for identifying quantitative and qualitative changes of proteins in human cancerous blood serum. However, what is very important, in PCA analysis we see, that the scatter plot of PC1 (variability 80%) and PC2 (variability 15%) show that the data related to the control and two cancer groups are clustered together with different magnitudes and directions.Recently, room temperature phosphorescence (RTP) feature of carbon dots (CDs) has gradually diverted researchers' attention from fluorescence and sparks new research boom due to its ultra-long luminescence lifetime and large Stokes shift. Some attempts have been made to construct CDs-based RTP materials, and had seen some important progress. However, few review articles were published to systematically summarize them. Herein, we summarize the recent synthesis advances of the RTP CDs, mainly focusing on matrix-assisted method and self-protection method. Different construction methodologies lead to different RTP properties and luminescence mechanisms. Based on this fact, we discuss the correlation between them and further summarize their potential applications in sensing, light-emitting diodes, anti-counterfeiting, and information protection filed. Finally, the currently existing problems and development perspectives of CDs-based RTP materials was proposed.Covalent organic frameworks (COFs) showed great promise in effective adsorption of target molecule via size selectivity. Although various magnetic 2D COFs composites have been studied and exhibited the intensive applications, the incorporation of 3D COFs and magnetic nanoparticles to form a new class of magnetic adsorbents with enhanced function still has no reports. Herein, a novel Fe3O4@3D COF with heteroporous structure matching to the sizes of bisphenol A (BPA) was firstly synthesized for better adsorption of BPA than common magnetic 2D-COFs. Three Fe3O4@3D COFs nanospheres were synthesized under the solvothermal conditions in autoclave, and the optimum Fe3O4@3D-COF denoted as Fe3O4@COF-TpTAM (Tp, 1,3,5-triformylphloroglucinol; TAM, tetra(p-aminophenyl)-methane) was selected and employed. https://www.selleckchem.com/products/eeyarestatin-i.html Detailed characteristics of Fe3O4@COF-TpTAM were evaluated via various techniques including TEM, FTIR, TGA, XRD and BET. Excellent chemical and thermal stability, high surface area (294.6 m2 g-1) and pore volume (0.2 m3 g-1) with multiple pore sizes comparable with the simulated three-dimensional sizes of BPA were exhibited.