Experimental studies of bubble cutting in a lab-scale micro-structured bubble column with different liquid viscosity

Guanghui Chen,Zhongcheng Zhang,Fei Gao,Jianlong Li,Jipeng Dong 한국화학공학회 2022 Korean Journal of Chemical Engineering Vol.39 No.8

Bubble cutting was realized by installing a wire mesh in a micro-structured bubble column (MSBC) andstudied experimentally with liquid viscosity range from 1 to 39.6mPa·s. A non-intrusive high-speed camera methodwas used to determine bubble size and size distribution. The changes of gas holdup, bubble size, size distribution andSauter mean diameter before and after cutting were systematically studied with mesh openings of 3.8mm and 5.5mm. Three novel bubble cutting behaviors with uniform cutting, detachment cutting and indirect cutting behavior wereobserved. In the presence of two wire meshes, the bubble size distribution roughly shows a Gaussian curve distributionand the peak tends to shift towards lower diameters. With increasing liquid viscosity and superficial gas velocity,the dominant peak tends to move towards higher diameters, resulting in poor mesh cutting effect. After cutting, in thecase of two wire meshes, the Sauter mean diameter decreased by 33.5% and 22.2% and the gas holdup increased by3.2-12.2% and 1.2-4.4%, respectively. For the case of 3.8 mm mesh opening, the interfacial area increased by 10-26%,which is much better than 5.5mm mesh. The mean bubble size above the mesh will grow again and its growth ratedepends on the liquid viscosity.

Treatment with low-energy shock wave alleviates pain in an animal model of uroplakin 3A-induced autoimmune interstitial cystitis/painful bladder syndrome

Huixi Li,Zhichao Zhang,Jing Peng,Zhongcheng Xin,Meng Li,Bicheng Yang,Dong Fang,Yuan Tang,Yinglu Guo 대한비뇨의학회 2019 Investigative and Clinical Urology Vol.60 No.5

Purpose: To investigate whether treatment with low-energy shock wave (LESW) alleviates pain and bladder dysfunction in a mouse model of uroplakin 3A (UPK3A)-induced interstitial cystitis/painful bladder syndrome (IC/PBS). Materials and Methods: Forty female BALB/c mice were divided into four groups (n=10/group): Sham, Sham+LESW, UPK3A, and UPK3A+LESW. At 6 weeks of age, mice were injected with an emulsion containing water and complete Freund's adjuvant with (UPK3A and UPK3A+LESW groups) or without (Sham and Sham+LESW groups) 200 µg of UPK3A. At 10 weeks, mice received a second dose of Freund's adjuvant to booster immunization. At 12 weeks, mice underwent pain assessment and a frequency volume chart (FVC) test as the pretreatment assessment. LESW treatment and pain assessment were conducted from 13 to 15 weeks. One week after the final treatment, pain assessment and the FVC were conducted again as the post-treatment assessment. Mice were euthanized and sacrificed at 17 weeks. Results: The presence of tactile allodynia and bladder dysfunction was significant in the UPK3A-injected mice. LESW raised the pain threshold and improved bladder function with decreased urinary frequency and increased mean urine output. Expression and secretion of local and systemic inflammatory markers, including tumor necrosis factor-α (TNF-α) and nerve growth factor (NGF), increased after UPK3A immunization. These markers were significantly decreased after LESW treatment (p<0.05). Conclusions: LESW treatment attenuated pain and bladder dysfunction in a UPK3A-induced model of IC/PBS. Local and systemic inflammation was partially controlled, with a reduced number of infiltrated inflammatory cells and reduced levels of TNF-α and NGF.

Impact test of a centrifugal pump used in nuclear power plant under aircraft crash scenario

Huang, Tao,Chen, Mengmeng,Li, Zhongcheng,Dong, Zhanfa,Zhang, Tiejian,Zhou, Zhiguang Korean Nuclear Society 2021 Nuclear Engineering and Technology Vol.53 No.6

Resisting an accidental impact of large commercial aircrafts is an important aspect of advanced nuclear power plant (NPP) design. Especially after the 9·11 event, some regulations were enacted, which required the design of NPPs should consider the accidental impact of large commercial aircrafts. Normal working of equipment is important for stopping reactor under an impact when an NPP is in operation. However, there is a lack of reliable analysis and research on the impact test of nuclear prototype equipment. Therefore, in order to study the response of the equipment under high acceleration impact, a centrifugal pump is selected as the research object to perform the impact test. A horizontal half-sinusoidal pulse wave was applied to the working pump. The test results show that the horizontal response of the motor and flange is greater compared to other parts, as well as the vertical response of the coupling. The stress response of the pump body support and motor support is high, hence these parts should be considered in the design of the pump. Finally, combined with the damage and stress evaluation results of the pump under different amplitudes, the ultimate impact acceleration that the pump can withstand is given.

Experimental and mechanism research on volatilization characteristics of HCl in desulfurization wastewater evaporation process using high temperature flue gas

Ma Shuangchen,Chai Jin,Wu Kai,Wan Zhongcheng,Xiang Yajun,Zhang Jingrui,Fan Zixuan 한국공업화학회 2018 Journal of Industrial and Engineering Chemistry Vol.66 No.-

Due to the promulgation of “water pollution control action plan” in China, zero liquid discharge of desulfurization wastewater has become a new trend for water pollution control in power plants. The HCl volatilization in desulfurization wastewater evaporation process is the key problem that may influence the application of evaporation technology, so experiment was carried out in self-made experimental system. The effects of temperature, pH, Cl− concentration, total dissolved solids and main metal ions on HCl volatilization were explored. Results have shown that HCl volatilization increases respectively from 5.42% to 20.43% and 2.22% to 9.18% with the increasing temperature from 180 °C to 380 °C in two kinds of actual desulfurization wastewater evaporation process. When pH < 7, Cl− concentration is the main influencing factor on HCl volatilization; the higher Cl− concentration is, the higher HCl volatilization will be observed. While pH > 7, pH becomes the dominant factor, increasing pH will inhibit HCl volatilization; Mechanism of HCl volatilization was studied simultaneously by XRD and TGA. Gaseous HCl mainly comes from the combination of free H+ and Cl−, hydrolysis of Ca2+ and Mg2+ in liquid phase and hydrolysis of hydrate in high temperature solid phase; Ways to inhibit HCl volatilization in process were put forward according to the experimental results. The use of Ca(OH)2 to adjust the pH of desulfurization wastewater to 9.0–10.0 can inhibit HCl volatilization economically and efficiently. This study provides the key data for the application of flue gas evaporation technology under high temperature. The research results have important theoretical and practical values for the engineering practice of this technology.

Circ_0001686 Promotes Prostate Cancer Progression by Up-Regulating SMAD3/TGFBR2 via miR-411-5p

Pan Jiancheng,Liu Zihao,Yang Zhizhao,Liang Enli,Fang Cheng,Zhang Dingrong,Zhou Xiaodong,Niu Yuanjie,Xin Zhongcheng,Chen Yegang,Cai Qiliang 대한남성과학회 2022 The World Journal of Men's Health Vol.40 No.1

Purpose: As the mechanism of interaction between circular RNAs (circRNAs) and microRNAs (miRNAs) in regulating the development of prostate cancer (PCa) is not clear, this study focuses on investigating these effects. Materials and Methods: Sample tissues were collected from the PCa of patients, and microarray analysis of human circRNAs was conducted. The expression of circ_0001686, hsa_miR-411-5p (miR-411-5p) were also detected by qRT-PCR. Circ_0001686 and miR-411-5p mimics were transfected into the PCa cell lines (CWR22RV1and LNCaP) and MTT, colony formation, Transwell, and scratch wound assays were used to analyze the biological behaviors of PCa cells. Si-circ_0001686 and ASO-miR-411-5p were used as negative controls, and dual-luciferase reporter assays were performed to verify the interactions among circ_0001686, miR-411-5p, and SMAD3/TGFBR2. The levels of SMAD3 and TGFBR2 in different treated PCa cells were measured by western blot, and in vivo experiments in a nude mouse model were carried out to strengthen the in vitro findings of miR-411-5p. Results: The expression of circ_0001686 was up-regulated, while the expression of miR-411-5p was down-regulated in PCa cells. Moreover, circ_0001686 promoted cell proliferation, migration, and invasion. Molecular mechanism exploration revealed that circ_0001686 could reduce miR-411-5p, affecting the downstream target genes of SMAD3 and TGFBR2. In vitro and in vivo studies verified that miR-411-5p inhibits PCa progression. Conclusions: Circ_0001686 can reduce miR-411-5p to increase the expression of SMAD3/TGFBR2, which consequently promotes the proliferation, invasion, and migration of PCa cells.