Characterization of microstructure and oxidation resistance of Y and Ge modified silicide coating on Nb-Si based alloy

Y and Ge modified silicide coating was prepared on the Nb-Si based alloy by Si–Ge–Y co-deposition at 1300°C for 10h. The coating consists of an outer layer and a transitional layer(Fig.1a). The outer layer is consist of( Nb , X )(Si, Ge)2(X represents Ti, Cr, Ge and Hf elements) and the transitional layer is composed of ( Nb , X )5(Si, Ge)3. The mass gain of the coated specimen is 2.78 mg cm−2 after oxidation at 1250 °C for 100 h(Fig.1b), which reveals that Ge and Y modified silicide coating exhibits better oxidation resistance than Ge-modified silicide coating and Y element is significantly beneficial for the oxidation resistance. The results indicate that Y refines grain size due to the formation of Y3Al5O12 particles at grain boundaries, which could promote the rapid formation of protective SiO2 and GeO2 scale, and then oxygen diffusion could be decreased. Therefore, the oxidation resistance of the coating is improved. Please click Additional Files below to see the full abstract

An investigation of yarn snarling and balloon flutter instabilities in ring spinning

This article reports theoretical and experimental investigation on yarn snarling and balloon fluttering in ring spinning. Yarn snarling and balloon fluttering affect yarn breakage in ring spinning. The theoretical model has incorporated the tangential component of air drag on a ballooning yarn, which was ignored in previous models. The results show that yarn snarling happens in the balloon when the ratio of yarn length in the balloon to balloon height is greater than a specific value that depends on the yarn type and count. Yarn tension experiences an obvious change before and after yarn snarling. The balloon flutter appears between normal balloons while the balloon loops are changing. Fluttering balloon shapes that oscillate periodically between two and three loop configurations as yarn tension varies periodically have also been observed experimentally. <br /

τ

Let A be a finite dimensional algebra over an algebraic closed field k. In this note, we will show that if T is a separating and splitting tilting A-module, then τ-complexities of A and B are equal, where B=EndA(T)

Effect of tumor and normal lung volumes on the lung volume–dose parameters of IMRT in non–small-cell lung cancer

OBJECTIVES: To explore the effect of tumor and normal lung volumes on lung volume-dose parameters in patients with non-small-cell lung cancer (NSCLC) who had undergone intensity-modulated radiation therapy (IMRT). METHODS: The clinical data of 208 patients with NSCLC who underwent radical IMRT between June 2014 and June 2018 were retrospectively analyzed. A regression model curve was used to evaluate the effect of tumor and normal lung volumes on normal lung relative volumes receiving greater than 5 and 20 Gy (V5, V20), on mean lung dose (MLD), and on absolute volumes spared from greater than 5 and 20 Gy (AVS5, AVS20). RESULTS: The V5, V20, and MLD of the bilateral lung were fitted to a quadratic equation curve with the change in tumor volume, which increased initially and then decreased when the tumor volume increased. The V5, V20, and MLD of the lung reached their apex when the tumor volumes were 288.07, 341.69, and 326.83 cm3, respectively. AVS5 and AVS20 decreased in a logarithmic curve with an increase in tumor volume. The V5, V20, and MLD of the small normal lung volume group were all significantly higher than those of the large normal lung volume group (p&lt;0.001,&nbsp;p=0.004,&nbsp;p=0.002). However, the AVS5 and AVS20 of the small normal lung volume group were all significantly lower than those of the large normal lung volume group (p&lt;0.001). CONCLUSION: The effects of tumor volume and normal lung volume on dose-volume parameters should be considered. AVS5 is an important supplementary dose limitation parameter for patients whose tumor volume exceeds a certain boundary value (approximately 300 cm3)

Preoperative pelvic floor muscle exercise for continence after radical prostatectomy: a systematic review and meta-analysis

ObjectiveWe performed a systematic review and meta-analysis to evaluate the effect of preoperative pelvic floor muscle exercise on urinary incontinence after radical prostatectomy.MethodsWe searched the literature for randomized controlled trials evaluating the diagnostic analysis of preoperative pelvic floor muscle exercise (PFME) and postprostatectomy incontinence in the MEDLINE, EMBASE, PubMed, Cochrane Central Register of Controlled Trials (CENTRAL), PsycINFO, China Biomedical Literature Database, China Journal Full-text Database, Wanfang Database and Weipu Database. The retrieval time limit is from the establishment of the database to January 2023. We used a risk ratio with accompanying 95% confidence interval (CI) to express estimates. Reviewer Manager (RevMan) 5.1.0 was used to complete all statistical analyses.ResultsTwelve studies were included based on the selection criteria. The total number of patients included in the final analysis was 1,365. At 1th month, there was no difference in continence rates between the groups [odds ratio (OR): 0.47; 95% confidence interval (CI), 0.22–1.02, p = 0.06]. At 3th month, there was statistically significant difference in PFME group before operation (OR: 0.61; 95% CI, 0.37–0.98, p = 0.04). At 6th and 12th months, there was no difference between groups (OR: 0.57; 95% CI, 0.28–1.17, p = 0.13), (OR: 0.56; 95% CI, 0.27–1.15, p = 0.12).ConclusionPreoperative pelvic floor muscle exercise can improve postoperative urinary incontinence at 3rd months after radical prostatectomy, but it cannot improve urinary incontinence at 6th months or longer after surgery, which indicates that preoperative PFME can improve early continence rate, but cannot improve long-term urinary incontinence continence rate

The effect of yarn hairiness on air drag in ring spinning

Air drag on yarn and package surfaces affects yarn tension, which in turn affects energy consumption and ends-down in ring spinning. This study investigated the effects of yarn hairiness on air drag in ring spinning. Theoretical models of skin friction coefficient on the surface of rotating yarn packages were developed. The predicted results were verified with experimental data obtained from cotton and wool yarns. The results show that hairiness increases the air drag by about one-quarter and one-third for the rotating cotton and wool yarn packages, respectively. In addition, yarn hairiness increases the air drag by about one-tenth on a ballooning cotton yarn.<br /