There is, I think, something ethereal about i —the square root of minus one. I remember first hearing about it at school. It seemed an odd beast at that time—an intruder hovering on the edge of reality.

Usually familiarity dulls this sense of the bizarre, but in the case of i it was the reverse: over the years the sense of its surreal nature intensified. It seemed that it was impossible to write mathematics that described the real world in …

I and i

다중혈관 관상동맥 환자에서 y-문합을 이용하여 양쪽 내흉동맥만을 사용한 우회술의 조기 성적

THE DESIGN AND ANALYSIS OF EXPERIMENTS. By Oscar Kempthorne. New York, John Wiley and Sons, Inc., 1952. 631 pp. $8.50. This book by a teacher of statistics (as well as a consultant for \"experimenters\") is a comprehensive study of the philosophical background for the statistical design of experiment. It is necessary to have some facility with algebraic notation and manipulation to be able to use the volume intelligently. The problems are presented from the theoretical point of view, without such practical examples as would be helpful for those not acquainted with mathematics. The mathematical justification for the techniques is given. As a somewhat advanced treatment of the design and analysis of experiments, this volume will be interesting and helpful for many who approach statistics theoretically as well as practically. With emphasis on the \"why,\" and with description given broadly, the author relates the subject matter to the general theory of statistics and to the general problem of experimental inference. MARGARET J. ROBERTSON

The Design and Analysis of Experiments

[신간의 별자리x] 우리/미술, 그리고 ‘슬픔의 박물관’

비만아 부모의 돌봄 경험: q 방법론

Characterization of the temperature and oxygen concentration field in a decentralized solid-waste incinerator for villages and towns

Bioaugmentation with degrading bacteria can improve the treatment of nicotine-containing tobacco industrial wastewater effectively. However, the transient and extremely high feeding of pollutants may compromise the effectiveness of the bioaugmented reactors. The effect of transient nicotine shock loads on the performance of Pseudomonas sp. HF-1 bioaugmented SBRs were studied. The results showed that, under 500–2500 mg/L of transient nicotine shocks, all the reactors still could realize 100% of nicotine degradation in 4 days of recovery, while the key nicotine degradation enzyme HSP hydroxylase increased in expression. Though the dramatic increase of activities of ROS, MDA, SOD, and CAT suggested that transient nicotine shock loads could induce oxidative stress on microorganisms in activated sludge, a decrease to control level demonstrated that most of the microorganisms could resist 500–1500 mg/L of transient nicotine shock under the protection from strain HF-1. After 8 cycles of recovery, high ROS level and low TOC removal in high transient shock reactors implied that 2000–2500 mg/L of transient nicotine shock was out of its recovery of strain HF-1 bioaugmented system. This study enriched our understanding on highly efficient nicotine-degrading strain bioaugmented system, which would be beneficial to tobacco waste or wastewater treatment in engineering.

/pdf/effect-of-transient-nicotine-load-shock-on-the-performance-4r349crg4c.pdf

Effect of Transient Nicotine Load Shock on the Performance of Pseudomonas sp. HF-1 Bioaugmented Sequencing Batch Reactors

Persulfate is considered a convenient and efficient remediation agent for organic contaminated soil. However, the potential risk of sulfur into the soil remediation by persulfate remains ignored. In this study, glass bottles with different persulfate dosages and groundwater tables were set up to simulate persulfate remediation of organic pollutants (aniline). The results found sulfate to be the main end-product (83.0%‒99.5%) of persulfate remediation after 10 days. Moreover, H2S accounted for 93.4%‒99.4% of sulfur reduction end-products, suggesting that H2S was the final fate of sulfur. H2S was released rapidly after one to three days at a maximum concentration of 33.0 ppm, which is sufficient to make a person uncomfortable. According to the fitted curve results, H2S concentration decreased to a safe concentration (0.15 ppm) after 20‒85 days. Meanwhile, the maximum concentration of methanethiol reached 0.6 ppm. These results indicated that secondary pollution from persulfate remediation could release harmful gases over a long time. Therefore, persulfate should be used more carefully as a remediation agent for soil contamination. 

Potential risks of organic contaminated soil after persulfate remediation: Harmful gaseous sulfur release

From corn stover to 5-hydroxymethylfurfural by ball milling-microwave hydrothermal (BM-MHT)


 Aniline is a kind of refractory contaminant that is difficult to be degraded by microorganisms. Ozone is a green and efficient reagent to oxidize aniline, while the ozone oxidation efficiency is restricted by the low ozone mass transfer rate. Micro-nano bubble ozonation has been developed as a new method to significantly improve the ozone utilization rate, while the characteristics of ozone micro-nano bubble when compared with dissolved ozone is not clear. The paper carried out batch experiments to research the oxidation effect of aniline by ozone water (OW) and ozone micro-nano bubble water (OMNBW), and found that the degradation rate of aniline by OMNBW was 2.8~5.9% higher than that by OW. The increase of pH had a negative effect on the degradation of aniline by OW and OMNBW. SO42-, Cl-, HCO­3- and Mg2+ could inhibit the degradation efficiency by 0.04%, 0.99%, 0.44% and 10.4% for OW, while the ratios were 1.1%, 6.4%, 4.1% and 1.5% for OMNBW. The addition of humic acid and fulvic acid could decrease the oxidation rate of aniline by 35% and 49% for OW, while the ratios were 41% and 62% for OMNBW. Through quenching experiment, it was found that the direct oxidation by ozone molecules and the indirect oxidation by superoxide radicals were main pathways for aniline oxidation by OW and OMNBW. This work provided a practical guide for the application of OMNBW in wastewater and groundwater treatment process.

/pdf/the-oxidation-mechanism-of-aniline-by-ozone-water-and-ozone-1caxeyzh.pdf

Dongsheng Shen

Papers

Characterization of the temperature and oxygen concentration field in a decentralized solid-waste incinerator for villages and towns

Effect of Transient Nicotine Load Shock on the Performance of Pseudomonas sp. HF-1 Bioaugmented Sequencing Batch Reactors

Potential risks of organic contaminated soil after persulfate remediation: Harmful gaseous sulfur release

From corn stover to 5-hydroxymethylfurfural by ball milling-microwave hydrothermal (BM-MHT)

The Oxidation Mechanism of Aniline by Ozone Water and Ozone Micro-nano Bubble Water and Its Influencing Factors