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(目的 探讨患者参与监督对提高血透室护士手卫生依从性和正确性的影响。方法 采用现场观察的方法, 评估血透室护士手卫生执行情况。2020年6月开始实施干预措施, 比较干预后(2020年6月—8月)与干预前(2020年3月—5月)血透室护士手卫生的执行情况。结果 血透室护士手卫生依从率从干预前的63. 02%(1525/2420)提高至92. 16%(2868/3112); 手卫生依从性的正确率从干预前的41. 90% (639/1525)提高至74. 51%(2137/2868)。结论 患者参与监督可以提高血透室护士手卫生的依从性和正确性。)

Volatile organic compounds (VOCs) are another type of serious pollutant except for participate matter and sulfur dioxide, and therefore the control of VOCs has become a public concern in recent years. The porous materials with an adsorption capacity play an important role in the treatment: of VOCs. In this paper, the preparation methods, chemical composition, structural characteristics, adsorption properties and reliever mechanisms of a series of approvers adsorbents were introduced, and the appearing of adsorbents for removal of VOCs in polymer processing was summarized. Moreover, the development prospects of adsorbents Were discussed. [ABSTRACT FROM AUTHOR]

For discussing the change of land system and spatial agglomeration pattern in sandy area of northern Yanchi during the past 25 years, land use vector data from the interpretation of TM remote sensing images (in the years of 1989, 1995, 2000 and 2007) and ZY-1 O2C satellite image (in the year of 2012) were used as the data sources. The spatial-temporal dynamic change characteristics were comprehensively analyzed by building land use change network model and information entropy model. The former model was used to quantify some elements such as direction, status and trend, which could effectively characterize some significant aspects associated with land change; the latter model was used to describe and express the order degree of the land use system. Furthermore, the spatial agglomeration pattern was expressed by using the GIS density mapping method. Results showed that tremendous changes had taken place in the past 25 years for the land use types in sandy area of northern Yanchi. Cultivated land and unused land showed a drastic reduction, while woodland and grassland expanded significantly, and human activities in the study area were in a positive way to gradually optimize and influence the evolution of landscape pattern Different degrees of mutual transformation appeared between various land use types, among which grassland, woodland, cultivated land and unused land played key roles in the whole network of land use change, and thus determined the characteristics of land use change in the sandy area. The land system change process showed an evolution trend from "balanced" type, "weak balanced" type to "not balanced" type during the past 25 years. Information entropy and equilibrium degree of land use structure was in a fluctuation drop situation, while advantage degree was in a fluctuation upward trend; overall, the land use system of the study area was developing towards a relatively orderly state. From the perspective of spatial analysis, the regions near woodland and cultivated land were hot spots of land use change and the spatial agglomeration features of land use change were different at different periods. Taking the year of 1995 as the demarcation point, the hot zone of land use change was distributed from northeast to southwest direction from 1989 to 1995, however, the hot spot gradually transferred from west to east of the whole region from 1995 to 2012. Through the restoration of vegetation, the ecological environment in the study area had been improved to a large extent, and a land use pattern dominated by grassland and woodland had been formed gradually, effectively reducing the risk of desertification. These conclusions could provide a scientific basis for the research on the mechanism of land use change, sustainable use of land resources, as well as optimization of sandy habitat environment. [ABSTRACT FROM AUTHOR]

Polymeric monolithic columns are fabricated by in situ polymerization of the corresponding monomer, crosslinkers, porogenic solvents and radical initiators within a mold. Compared with the conventional packed solid phase extraction adsorbents, polymeric monolithic columns with a continuous porous structure process distinctive advantages of rapid mass transfer and excellent permeability, which facilitates the extraction of trace amounts of the target from the matrix even at high flow velocities. Besides, these materials can be easily fabricated in situ within various cartridges, avoiding a further packing step associated with packed particulate adsorbents. Additionally, the abundant monomer availability, flexible porous structure, and wide applicable pH range make monoliths versatile for use in separation science. Thus, polymeric monolithic columns have been increasingly applied as efficient and promising extraction media for sample pretreatment food, pharmaceutical, biological and environmental analyses. However, these materials usually have the difficulty in morphology control and their interconnected porous micro-globular structure, which may result in low porosity, limited specific surface area and poor efficiency. In addition, polymeric monoliths suffer from the swelling in organic solvents, thus decreasing the service life and precision while increasing the cost consumption. Recently, the development of nanomaterial-incorporated polymeric monoliths with an improved ordered structure, enhanced adsorption efficiency and outstanding selectivity has attracted considerable attention. Nanoparticles are considered as particulates within the size range of 1-100 nm in at least one dimension, which endows them with unique optical, electrical and magnetic properties. These materials have a large surface area, excellent thermal and chemical stabilities, remarkable versatility, as well as a wide variety of active functional groups on their surface. With the aim of exploiting these advantages, researchers have shown great interest in applying nanomaterial-incorporated polymeric monoliths to separation science. Accordingly, significant progress has been achieved in this field. Nanomaterials can be entrapped via the direct synthesis of a polymerization solution that contains well dispersed nanomaterials in porogens. In addition, nanoparticles can be incorporated into the monolithic matrix by copolymerization and post-polymerization modification via specific interactions. Therefore, nanomaterial-incorporated polymeric monoliths combined the different shapes, chemical properties, and physical properties of the polymers with those of the nanoparticles. The presence of nanoparticles can improve the structural rigidity as well as the thermal and chemical stabilities of monolithic adsorbents. Besides, nanoparticles are capable of increasing the specific surface area and providing multiple active sites, which leads to enhanced extraction performance and selectivity of polymeric monolithic materials. In recent years, diverse types of nanomaterials, such as carbonaceous nanoparticles, metallic materials and metal oxides, metal-organic frameworks, covalent organic frameworks and inorganic nanoparticles have been extensively explored as hybrid adsorbents in the modes of solid phase extraction, solid phase microextraction, stir bar sorption extraction and on-line solid phase extraction. This review specifically summarizes the fabrication methods for nanomaterial incorporated polymeric monoliths and their application to the field of sample pretreatment. The existing challenges and future possible perspectives in the field are also discussed.

The complex matrix of rice samples and the small amount of the target analytes in the sample necessitate an effective pretreatment process to enrich the target analytes and minimize matrix interference before instrumental analysis. Magnetic solid phase extraction (MSPE) is a dispersive solid phase extraction technique which allows for the rapid separation of sorbents from the sample solution under an external magnetic field. Compared with other traditional solid phase extraction methods, MSPE has the advantages of convenient operation, minimal interference and absence of column pressure. In this work, a metal organic framework composite (Fe 3 O 4 @MOF-808) was synthesized by a facile solvothermal method for using as an effective adsorbent to concentrate nitrofen (NIT), oxyfluorfen (OXY) and bifenox (BIF) in rice samples. Based on the pretreatment, a method was developed by coupling with high performance liquid chromatography-ultraviolet detection (HPLC-UV). The prepared material was characterized by Fourier-transform infrared spectroscopy, X-ray diffractometry, scanning electron microscopy and vibrating sample magnetometry measurements for determining its functional groups, morphology and magnetic strength. The results showed that MOF-808 has a regular octahedral morphology and well-dispersed, and the particle size of the material ranged from 400 to 500 nm with a smooth surface. The spherical Fe 3 O 4 particles were uniformly attached to the surface of the octahedral MOF-808 crystals. The maximum saturation magnetization of this composite was 40.35 emu/g which is lower than the saturation magnetization Fe 3 O 4 (78.26 emu/g) but still sufficient for the requirements of MSPE. The prepared Fe 3 O 4 @MOF-808 was used in the MSPE of three diphenyl ether herbicides (Des) in rice. As is well known, the key factors influencing MSPE are the adsorption and elution processes. In order to establish the optimal extraction conditions, the adsorption parameters (adsorbent amount, extraction time, elution solvent and elution volume) were investigated in detail. A 15 mL mixed standard solution was used in the experiment, and the concentrations of the three Des were 65 ng/mL. All the experiments were performed in parallel three times. The effects of the dosages of Fe 3 O 4 @MOF-808 (10, 15, 20, 25 and 30 mg), adsorption time (2, 4, 6, 8 and 10 min), elution solvents (acetone, acetonitrile and methanol) and elution volume (0.5 mL, 0.5 mL×2, 0.5 mL×3, 0.5 mL×4) were investigated. The Des could be adsorbed completely by using 25 mg of Fe 3 O 4 @MOF-808 for no more than 6 min. Elution was performed with 0.5 mL×2 of methanol. Various parameters such as limits of detection (LODs), limits of quantification (LOQs), accuracy and precision of the method were evaluated. The method showed good linearity in the range of 2-300 μg/L ( r > 0.998). The LODs and LOQs were 0.6, 0.6, 0.4 μg/kg and 2.0, 2.0,1.5 μg/kg for NIT, OXY, BIF respectively. At spiked levels of 5, 10 and 20 μg/kg, the recoveries ranged from 87.3% to 96.7% with relative standard deviations (RSDs) less than 10.8%. The enrichment factors (EFs) of the method for the three Des were between 25 and 29. The method was applied to the pretreatment of the three Des in real samples, and none of the Des could be detected at any of the samples. This method had a lower LOD than that of the national standard method, but its LOD and recovery were similar to those of other reference methods. In summary, the developed method has the advantages of operational simplicity, rapidity and accuracy, and it is suitable for the analysis of herbicide residues in rice samples.

A polymer monolithic column was prepared in a syringe by using [2-(acryloyloxy) ethyl] trimethyl ammonium chloride (DAC) as a monomer and ethylene glycol dimethacrylate (EDMA) as a crosslinker. The obtained monolith was developed as a solid-phase extraction sorbent and used with high performance liquid chromatography (HPLC) for the analysis of three benzodiazepines (BZDs) including bromazepam (BRZ), lorazepam (LRZ) and diazepam (DZP) in urine. The effects of reaction time and the solid-phase extraction conditions (washing solution, elution solvent and volume) on the extraction efficiencies of the three BZDs were investigated. The monolithic column was successfully prepared within 4 h, and it offered 100% adsorption efficiency for the three BZDs. The urine sample (4 mL) was loaded on the monolith, washed with 4 mL of H 2 O, and eluted with 1 mL of ethyl acetate. Under the optimized conditions, the linear ranges were 4.0-1000 ng/mL for the three BZDs, with correlation coefficients ( r ) of 0.999. The limits of detection ( S/N =3) and limits of quantification ( S/N =10) of the three BZDs were in the range of 1.0-1.2 ng/mL and 3.3-4.0 ng/mL, respectively. The recoveries at three spiked levels (10, 25 and 50 ng/mL) of the three BZDs ranged from 81.4% to 102%, with intra-day and inter-day relative standard deviations ( n =3) of 1.2%-4.5% and 2.5%-8.3%. The polymer monolithic column provided effective purification for the three BZDs in urine and the enrichment factor was 12-15. This polymer monolithic adsorbent has the advantages of easy preparation and high extraction efficiency. It is successfully applied to the determination of the three BZDs in urine samples.

A method based on the magnetic solid-phase extraction using magnetic carbon nitride composites coupled with high performance liquid chromatography-fluorescence detector (HPLC-FLD) was developed for the simultaneous determination of three hydroxyl polycyclic aromatic hydrocarbons (OH-PAHs) in urine. The synthesized sorbent was characterized by scanning electron microscope, X-ray diffractometer, vibrating sample magnetometer and surface area analyzer. The extraction parameters such as amount of sorbent, extraction time, eluting solvent and volume (single eluting volume×eluting times) were investigated in detail. Under the optimized conditions, the method showed a linear range of 0.25-250 μg/L (correlation coefficient=0.999). The limit of detection was 0.08 μg/L and the limit of quantification was 0.25 μg/L for each analyte. The proposed method gave a recovery of 90.1%-102%. The relative standard deviations for the intra-day and inter-day were 1.5%-7.7% and 2.2%-8.7%, respectively. The feasibility of the developed method was further demonstrated during the analysis of real samples. The results indicate that the magnetic carbon nitride composites can be used for the effective purification and enrichment of three OH-PAHs in urine. In addition, the method can be applied for analysis of urinary OH-PAHs in a simple, fast, and effective manner.

A polymeric monolithic solid phase extraction sorbent was fabricated from sole ethylene glycol dimethacrylate in a syringe and applied as a sorbent for the determination of carbamazepine (CBZ) and 10-hydroxy-carbamazepine (MHD) in human serum using high performance liquid chromatography. The effects of reaction temperature and reaction time on the extraction performance of the target compounds were investigated. The parameters, such as washing solvent, and elution solution and its volume, were optimized. Under the optimized condition, the purification and enrichment of CBZ and MHD in human serum were successfully achieved on the proposed poly ethylene glycol dimethacrylate (EDMA) monolithic column. The linear ranges were 0.02-40 μg/mL for CBZ and 0.05-100 μg/mL for MHD. The results indicated that the method exhibited good linearity in the corresponding ranges with the correlation coefficients ( r ) of 0.999. The limits of detection ( S/N =3) of CBZ and MHD were 0.004 μg/mL and 0.01 μg/mL, respectively. The average recoveries at three spiked levels of CBZ and MHD were 92.7% and 94.2%, respectively, with relative standard deviations (RSDs) ≤ 6.1%. Furthermore, the intra column to column ( n =3) and inter batch to batch ( n =5) RSDs were no more than 5.3%. The RSDs of eight repeated extraction cycles were no more than 5.8%. The developed method is effective and simple, and is suitable for the determination of CBZ and MHD in human serum.

A method based on monolithic column solid-phase extraction (SPE) coupled with high performance liquid chromatography (HPLC) was developed for the simultaneous determination of four hydroxyl polycyclic aromatic hydrocarbons (OH-PAHs) in urine.A poly (butyl methacrylate-co-ethylene dimethacrylate) monolithic column was prepared in a syringe and was used as the sorbent.The parameters influencing SPE, such as loading volume, washing solvent, eluent, and elution volume, were investigated in detail.Under the optimized conditions, the linearities were obtained in range of 1.2-200.0 ng/mL, and the LODs and LOQs of the analytes were 0.06-0.09 ng/mL and 0.20-0.30 ng/mL, respectively.The intra-day and inter-day relative standard deviations were 1.4%-5.3% and 2.6%-7.3%, respectively.The recoveries evaluated using the spiked (3 ng/mL) urine samples of coke oven workers ranged from 78.2% to 117.0%.The feasibility of the developed method was further demonstrated for the analysis of the real samples.The results indicated that the reusable monolithic column enabled effective purification and enrichment of the four OH-PAHs in urine, and can be applied to the analysis of OH-PAHs in urine due to its simplicity and accuracy.

A method based on on-line solid-phase extraction (SPE) with hydrophobic monolithic column coupled with high performance liquid chromatography-tandem mass spectrometry was developed for the simultaneous determination of five avermectins in bovine liver. A poly(butyl methacrylate-co-ethylene dimethacrylate) monolithic column was used as the sorbent. The parameters influenced on on-line SPE and separation process such as the loading mobile phase, the eluting flow rate and the solvent for the separation were investigated in detail. Blank samples, spiked samples, matrix effect and recovery experiments were investigated to evaluate the extraction efficiency and potential interfering compounds originating from the matrix. Under the optimized conditions, the method showed a linear range of 1-100 µg/L and the quantification limit of 5 µg/kg for each analyte. The presented method gave recoveries of 77.4%-98.4%. The relative standard deviations of intra-day and inter-day were 4.46%-8.03% and 4.79%-8.68%, respectively. Moreover, no significant changes were found in the extraction performance after more than 400 usages on one monolithic column, and even on the monoliths with various batches. The feasibility of the developed poly (butyl methacrylate-coethylene dimethacrylate) monolithic column based on the on-line SPE method for the determination of avermectins was further demonstrated by the analysis of real samples.

A weak anion exchange column was prepared and a separation method of interleukin-18 (IL-18) was developed on the column. The chromatographic column with glycidyl methacrylate as functional monomer and ethylene dimethacrylate as cross-linker was prepared by a free radical polymerization within a 64 mm x 4.6 mm i.d. column. The epoxide groups of the column were modified by a reaction with diethylamine that affords ionizable functionalities required for ion exchange chromatography. The influences of the contents of the cross-linker and porogen on column pressure were investigated. The factors influencing the separation, such as stationary phases, buffers, pH values, salts, and contents of organic solvent, were studied. The optimal conditions for separating IL-18 from its related proteins were obtained. The proposed method is simple, sensitive, rapid and reproducible.