Optimising Complex Surgical Trays Based on PDSA Cycles.

Objective: To investigate the application of a multidisciplinary collaboration model to optimise the configuration management of orthopaedic external device sets in general hospitals. Methods: A pretest-post-test study design was used. Sixty patients who underwent unilateral total knee arthroplasty and 60 patients who underwent posterior lumbar interbody fusion between March and May 2022 were recruited as the control stage. Additionally, a total of 120 patients, 60 of each, who underwent the two procedures between September and November 2022, were recruited as the experimental stage. For the control stage, conventional external equipment management was used, and for the experimental stage, an external device management programme was implemented based on multidisciplinary collaboration with the control stage. Based on the PDSA cycle, the configuration management of orthopaedic external device sets was optimised, and the differences in collating and counting external devices, nurses' overtime in the external device stage and orthopaedic surgeon satisfaction were compared between the two stages. Results: Compared with the control stage, the collation count took less time (8.65 ± 0.25 min vs 5.37 ± 0.13 min; 13.55 ± 1.10 min vs 7.85 ± 0.82 min), the number of overtime hours was shorter (175.80 ± 12.19 min vs 96.68 ± 13.66 min) and orthopaedic surgeon satisfaction was improved (4.58 ± 0.62 vs 4.10 ± 0.68; 4.33 ± 0.73 vs 3.87 ± 0.77; 4.20 ± 0.71 vs 3.82 ± 0.71; 4.12 ± 0.69 vs 3.87 ± 0.72; 4.05 ± 0.68 vs 3.79 ± 0.68) in the experimental stage (all P < 0.05). Conclusion: Multidisciplinary collaboration offers various benefits for optimising the configuration of external device sets, such as reducing the time taken for the preoperative sorting and counting of external devices, enhancing nurses' work efficiency and improving surgeons' job satisfaction; therefore, it is worthy of reference in clinical practice.

[Combined Process of DNBF-O3-GAC for Nitrogen and Phosphorus and Metabolite Advanced Removal].

To improve the quality of the tailings water from a wastewater treatment plant (WWTP), a denitrification biofilter (DNBF) with a composite filler composed of a new slow-release organic-carbon source (SOC-F), sponge iron, and activated carbon was tested. Studies were conducted in the combined process of DNBF-O3-GAC to explore the efficiency of the advanced removal of nitrogen, phosphorus, and microbial metabolite by using synthetic effluent made from running water and chemicals. Corresponding comparative studies were conducted by using the secondary effluent from the WWTP. The microbial population structure in the biofilm of the denitrification biofilter was analyzed by adopting MiSeq high-throughput sequencing technologies. The results indicated that the combination process achieved high efficiency removal of nitrogen, phosphorus, and microbial metabolite. The average removal rate of NO3--N in the simulated and actual water period reached 88.87% and 79.99%, respectively; the average removal rate of TP reached 87.67% and 65.51%, respectively; and the average removal rate of UV254 reached 45.51% and 49.23%, respectively. Each processing unit had different functions. The changes in NO3--N, TN, TP, and TFe mainly occurred in the denitrification biofilter, and the removal of UV254 and the change in the three-dimensional fluorescence intensity mainly occurred in the ozone-activated carbon reactor. The cluster analysis at the genus level indicated that the denitrification system had sulfur autotrophic denitrifying bacteria and heterotrophic denitrifying bacteria. Sulfur autotrophic denitrification increased obviously in the actual water period when relatively lack of carbon sources, and the proportion of Thiobacillus increased from 7.44% to 29.62%. The complementary effect of sulfur autotrophic denitrification and heterotrophic denitrification had extended the use of the new slow-release carbon source.

[Preparation and Phosphorus Removal Mechanism of Highly Efficient Phosphorus Adsorbent Mg/Al-LDO].

Aiming at the problem of phosphorus removal in water, Mg/Al-layered double hydroxides (Mg/Al-LDHs) were synthesized via optimized constant pH co-precipitation method, and highly efficient phosphorus adsorbent Mg/Al-layered double oxide(Mg/Al-LDO) was obtained when it was calcined at high temperature. Based on the adsorption characteristics of phosphorus removal, the study combined Zeta potential, X-ray diffraction (XRD) and Fourier transform infrared spectroscopy (FTIR) to analyze the changes of isoelectric point, crystal structure and functional group before and after adsorption. In addition, Mg/Al-LDO of phosphorus adsorption mechanism was discussed. The results indicated that using the optimized co-precipitation method in the conditions of Mg/Al=2:1, calcination temperature 450℃, and calcination time 2 h, the Mg/Al-LDO adsorption capacity of phosphate was the best, and the maximum adsorption capacity could reach 176.94 mg·g-1, which was basically consistent with the theoretical adsorption capacity of 191.57 mg·g-1, far higher than those of Mg/Al-LDHs and other phosphorus adsorbents. The results showed that the experimental data has the best fitting result with pseudo-second-order kinetics model. The adsorption process was consistent with Langmuir adsorption isotherm model. The results of Zeta potential, XRD and FTIR showed that phosphorus adsorption of Mg/Al-LDO was accomplished co-operatively by electrostatic attraction, anion in layer, ions exchange, and surface co-ordination.

[Effects of Temperature on the Characteristics of Nitrogen and Phosphorus Removal and Microbial Community in SCSC-S/Fe].

In order to investigate the effect of temperature on the cellulose-degrading bacteria and denitrifying bacteria, the denitrification and phosphorus removal of solid carbon source of cellulose corncob+sulfur/sponge iron nitrogen and phosphorus removal composite system, abbreviated as SCSC-S/Fe, was analyzed under different temperature conditions, and the surface structure and microbial properties of corncob before and after reaction were analyzed by scanning electron microscope (SEM) and MiSeq high-throughput sequencing technologies. The results indicated that when temperature increased from 15, 20, 25 to 30℃, the average TN removal rate of the system increased from 78.88% to 92.70%, the average removal rate of TP increased from 82.58% to 89.15%;microbial properties showed that the surface reaction after corncob was dominated by spherical and rod-shaped microorganisms; the proportion of cellulose-degrading bacteria was 11.01% higher at 30℃ than 20℃, and the proportion of denitrifying bacteria decreased by 21.26%. It can be seen that the cellulose -degrading bacteria were more sensitive to the temperature than the denitrification bacteria, and more obviously affected by the temperature.

[Improving Nitrogen and Phosphorus Removal from Reclaimed Water Using a Novel Sulfur/Iron Composite Filler].

In order to improve the ability of denitrification and phosphorus removal from reclaimed water, a novel composite filler was prepared using sulfur powder and sponge iron powder, and a comparative experiment was constructed at different HRT(hydraulic retention time) and C/N(carbon-nitrogen ratio) conditions between the novel filler and the composite filler. The results showed that the efficiency of nitrogen and phosphorus removal on the novel filler was higher than that on the grain filler (more than 30% higher at HRT=4 h and C/N=1). Moreover, based on the 16S rRNA gene clone library, the denitrification system in the two reactors included sulfur autotrophic denitrification bacteria and heterotrophic denitrification bacteria, while the proportion of sulfur autotrophic denitrification bacteria in the novel filler system was higher. The dominant bacteria in the novel filler and composite filler were Sulfurimonas and Acinetobacter, respectively.

[Feasibility of 3BER-S Process for the Deep Denitrification in Synch with the Removal of PAEs from Reclaimed Water].

In order to investigate the feasibility of deep denitrification and simultaneous removing phthalate esters (PAEs) in the process of reclaimed water treatment uses three-dimensional biofilm-electrode reactor coupled with sulfur autotrophic deep denitrification technology (3BER-S), the technological characteristics and mechanisms were analyzed based on determining the static adsorption capacity of biofilm cultured active carbon fillers in 3BER-S reactor together with the operation results of dynamic denitrification and simultaneous PAEs removing. The results showed that the average adsorption rates of DBP, DEHP were 85.84% and 97.12% in the biofilm cultured active carbon fillers, the equilibrium adsorption capacities were 0.1426 mg x g(-1) and 0.162 mg(-1) and the time spans of reaching adsorption saturation were 120 min and 60 min, respectively; The existence of PAEs had no obvious effect on denitrification, the reactor effluent concentration of TN was in range of 1-2 mg x L(-1) before and after the addition of PAEs, and the average removal rate of TN reached above 94%; 3BER-S denitrification system showed significant ability in removing PAEs, leading to effluent concentrations of DBP and DEHP of no more than 6 microg x L(-1) with removal rates of above 96%; this was due to the synergistic effect of absorption, biodegradation and electrochemistry. After treatment with 3BER-S technology, DBP and DEHP in simulative municipal secondary effluent met the regulated limitation of The Reuse of Urban Recycling Water Quality Standard for Groundwater Recharge (GB/T 19772-2005).

[Phosphorus Removal Mechanism of Sulfur/Sponge Iron Composite Fillers Based on Denitrification].

In order to improve the phosphorus removal effect in the denitrification and phosphorus synchronous removal process by sulfur/sponge iron composite fillers, the phosphorus removal effect by different fillers with the coupling microorganisms was studied to analyze the denitrifying phosphorus removal mechanism of the microbial coupling sulfur/sponge iron composite fillers. The research result showed that the phosphorus removal ratio of sponge iron/sulfur composite fillers was over 95%, which was increased by 30% as compared to only sponge iron filler. In addition, the effluent TP concentration was reduced to less than 0.1 mg·L-1. The analysis of X-ray diffraction(XRD)and total iron concentration indicated that the main phosphorus removal system products which were produced in the corrosion and phosphorus removal process of sponge iron were FeOOH, FeS and Fe4 (PO4)3 (OH)3 deposits and dissolved iron ions; FeS and FeOOH which were the hydrolysis products of Fe2+ and Fe3+ converted PO43- to Fe4(PO4)3(OH)3 by adsorption and deposition so that phosphorus removal could be achieved. After the reactor of microbial coupling sulfur/sponge iron carbon composite fillers became stable, the removal efficiency of TN and TP could reach 90% and more than 83%, respectively; Corrosion of sponge iron and phosphorus removal process could also be promoted by biological iron and H+ that was produced in the sulfur autotrophic denitrification process, the system could realize the combination of "heterotrophic synergy autotrophic" composite denitrification and chemical phosphorus removal, and efficient denitrifying denitrification synchronous phosphorus removal process could be achieved in the urban sewage treatment plant.

[Operational Characteristics of the Simultaneous Nitrogen and Phosphorus Removal and Removal of Phthalate Esters by Three-dimensional Biofilm-electrode Coupled with Iron/Sulfur Reactor].

In order to explore the technological characteristics of the simultaneous removal of phthalate esters (PAEs) as well as nitrogen and phosphorus by the novel technology of three-dimensional biofilm-electrode coupled with iron/sulfur reactor (3DBER-S-Fe), the changes of the total nitrogen (TN),total phosphorus (TP),DBP,DEHP,NO3--N, SO42- and pH value were analyzed under the hydraulic retention time (HRT) of 8 h, 6 h and 4 h respectively. The results showed that 3DBER-S-Fe could remove nitrogen, phosphorus and PAEs effectively. Under the HRT of 8 h, 6 h and 4 h, the removal rates of TN were 80.99%, 78.85% and 64.76%; TP were 65.18%, 67.17% and 43.44%; DBP were 96.72%, 97.32% and 96.53%; DEHP were 91.89%, 81.57% and 74.30%, respectively. There were heterotrophic denitrification, hydrogen autotrophic denitrification and sulfur autotrophic denitrification processes in the 3DBER-S-Fe, the elemental sulfur could compensate for the relative shortage of denitrification electron donor caused by the increase of NO3--N load in the influent as a result of maintaining a high efficiency of the denitrification system when the HRT was shortened from 8h to 4h; the iron ions produced by the corrosion of the sponge iron filler in the system had a sustainable and efficient function of removing phosphorus by precipitation; the 3DBER-S-Fe process combined the interactions of physical adsorption, biological degradation and electrochemical processes which supported its high removal rates of DBP and DEHP under the different HRT conditions.

[Effects of Sulfur/sponge Iron Ratio for Deep Denitrification and Phosphorus Removal of Reclaimed Water].

To study the effects of sulfur/sponge iron ratio on denitrification and phosphorus removal, a series of static experiments were conducted using different ratios of sulfur and sponge iron. The results showed that the denitrification and phosphorus removal effect of sulfur/sponge iron composite fillers was significantly higher than that of single filler, and sulfur/sponge iron ratio was one of the key factors influencing nitrogen and phosphorus removal by composite fillers. When the volume ratio was equal to or greater than 1:1, the removal efficiency of TN and TP reached 85% and 97%, respectively. The denitrification and phosphorus removal process of the composite fillers both fitted second-order kinetic equation, the denitrification was dependent on heterotrophic denitrification and sulfur autotrophic denitrification; the phosphorus removal was mainly chemical phosphorus removal caused by sponge iron corrosion.

[Effects of pretreatment methods on corncob as carbon source for denitrification].

The corncob was pretreated by 1.5% NaOH, 1% H2SO4, 1.5% H2O2 and alkaline hydrogen peroxide (caustic soda solution with 1.5% H2O2) combined with ultraviolet radiation. And the characteristics of carbon released, denitrification and bio-attachment capability of using pretreated corncob as carbon source for denitrification were studied in carbon release and denitrification experiments in laboratory scale. The results showed that the denitrification efficiency and the utilizability of the carbon released by the corncob pretreated by alkali or alkaline hydrogen peroxide were significantly enhanced. Especially, for the alkali pretreatment method, the nitrate removal rate could still maintain higher than 90% after 41 days of denitrification experiments. Therefore, the alkali pretreatment method could improve the carbon release performance of the corncob and is beneficial for microbial adsorption and carbon source utilization.

[Comparison and optimization of cellulose carbon source for denitrification filter].

The quantity and quality of carbon released by four agriculture wastes included of cotton, rice hull, rice straw and corncob was analyzed for selecting a suitable cellulose filter medium as well as the carbon source in advanced denitrification of the reclaimed water. And the long-term denitrification efficiency and bio-attachment capability of four agriculture wastes was contrastively estimated by running denitrification experiments in laboratory scale. The results showed that DOM amount released by corncob was the highest at the beginning, and the DOM quality was also beneficial for microorganism growth and biofilm formation. The running denitrification experiments showed that corncob had better denitrification efficiency than that of other three carbon sources, and 284.544 g nitrate was removed by 2.5 g corncob within 46 days. Cotton and rice hull had better denitrification efficiency than corncob in the early time, but the long-term denitrification efficiency was lower than that of corncob. Rice straw can hardly be used by microorganism so as to have the lowest denitrification. Therefore, corncob was more suitable to be the denitrification biofilter filter medium and the carbon source in advanced denitrification of the reclaimed water.

[Recognition and analysis on primary metabolites of nonylphenol].

In order to discuss the nonylphenol (NP) biodegradability effect in the wastewater treatment process, the primary metabolites and route of NP had been analyzed in the molecular level by the interpretation of gas chromatography mass spectrometry (GC-MS) and the two experimental methods. A method was that activated sludge degraded two types of simulating sewage comparatively. Type-1 wastewater was made up of water, glucose, peptone and inorganic salts, and type-2 sewage was mixed up of NP and type-1 as comparison wastewater. The other experiment was that dominant bacteria group metabolized the culture medium contained NP as only organic carbon source. The results show that the NP primary metabolites from the activated sludge experiments are a series of short chain alkyl phenols with butyl, amyl or hexyls. There are different methyl branch structures correlated with isomerous nonyl of NP in the alkyls. The primary metabolites from the dominant bacteria experiment have alkyl phenols and benzene acetic. The bio-degradation pathways of NP would be that the long branches in nonyl of NP are firstly degraded into short methyl branches, which come into being a series of short chain alkyl phenols with different branch structures. The middle products should be further metabolized into simpler compounds, such as benzene acetic. Based on the endocrine disrupter characteristic of alkyl phenol compounds, the short chain alkyl phenol compounds still have estrogen hormone effect, and their environmental effect must be pay attention in the pollutant control of NP.

The accumulation of nonylphenol in a wastewater recycling process.

A mathematical model was developed in this paper to describe the nonylphenol (NP) accumulation in the effluent of a wastewater recycling system. The model quantitatively presented the relationships among the NP concentrations in the raw wastewater and the system effluent, the number of wastewater recycling cycles, the water recycling ratio, the system NP removal efficiency, and the NP accumulation factor. The mathematical model was then verified through experimental modeling of a wastewater recycling process, and it was indicated that the Pearson correlation coefficient between mathematical simulation and experimental modeling results was 0.652. The study results indicated that the NP accumulation factor of a wastewater recycling system would approach a constant for large number of wastewater recycling cycles given the wastewater recycling ratio and system NP removal efficiency. The results also revealed that the NP concentration in the effluent increased with the wastewater recycling ratio given the system NP removal efficiency, and the increase of NP removal efficiency would decrease the NP accumulation in the system effluent under a given wastewater recycling ratio condition. The model was then applied to compute the maximum wastewater recycling ratio, predict reclaimed water quality and direct the design and management of sewage recycling systems in China.

Quality and stability analysis for the rainfall water and surface runoff water in southeast region of Beijing Municipality.

In this study, water sampling was carried out extensively through collection of natural rainfall and municipal surface runoff water samples in the southeast region of Beijing Municipality during the period of June 2002 to July 2004. Chemical tests and measurements of collected water samples were conducted in the laboratory in order to evaluate rainwater quality and to analyze chemical stability of rainwater. The test results show that the collected rainfall water and surface runoff water were soft water and belonged to bicarbonate-calcium Type-I water category. The results also show that their pH levels were closely related to the strength of alkaline constituents in the rainwater. Water quality analysis indicated that the rainwater collected from the study region had been contaminated to a certain degree by nitrogen and organic compounds from intensive human activities. Water stability analysis focuses mainly on the potential of precipitation-dissolution of carbonate calcium (CaCO3). The results show that only the rainwater samples collected from traffic roads were oversaturated with respect to CaCO3 and had a tendency to precipitate, while other rainwater samples were unsaturated with respect to CaCO3 and had the potential to keep dissolving CaCO3 into rainwater. The results obtained in this study may help to develop better rainwater utilization strategies for alleviating the growing water shortage pressure faced by the City of Beijing.

[Determination of nonylphenol in wastewater by solid phase extraction gas chromatography mass spectrometry and multi-selective ions].

Nonylphenol (NP) having endocrine disrupter activity is an ultra trace component in sewage and reuse wastewater. There are many NP isomers in the wastewater because nonyl structure is different. The background impurity of the samples is very complex with many other components. So it is difficulty for quantitative analysis of NP in the samples. About seventy sewages and recycled wastewater samples were measured for the content of NP isomer mixtures by solid-phase extraction-gas chromatography-mass spectrometry and multi-selected ions monitoring (shortened as SPE-GC-MS-SIM). The results show that hydrophilic-lipophilic-equilibrium solid-phase extraction pole has selective adsorption for NP, so that the samples can be concentrated from 50 to 200 times. The five kinds of mass spectrum ions, i. e. 107, 121, 135, 149, 163, have higher abundance and distinct character. The sum of five selected ion monitoring (sigmaSIM) is from 54.4 to 73 percent of the total ion current for NP, which can accurately represent different NP isomers. Quantitative analysis base on the spectral integralof the sigmaSIM chromatograph can eliminate interference with background signal and ensure selectivity, accuracy and precision ofthe method.