Fluid Mud Dynamics and Its Correlation to Hydrodynamics in Jiaojiang River Estuary, China

Li Li,Wang Jiachen,Zheng Yiqun,Yao Yanming,Guan Weibing 한국해양과학기술원 2023 Ocean science journal Vol.58 No.1

The Jiaojiang Estuary is a macro-tidal estuary with high turbidity and funnel-shaped geomorphology. Estuarine geomorphology and shipping are highly afected by sediments and heavy coastal engineering. Based on observed data and numerical simulation results, we studied the characteristics of the suspended sediments and fuid mud in the estuary. By considering two-way coupling of water–sediment density and the process of fne sediment focculation, a three-dimensional sediment model of the Jiaojiang Estuary was established and efectively calibrated using the measured data on tides, currents, and suspended sediment concentration (SSC). Field data analysis indicated that SSC and sediment transport rate in both the main tidal channel and shoals were positively correlated with the fow velocity in the low-frequency part during both the spring and neap tides. The model results revealed that the net sediment fux is controlled by advection and moves landward upstream of the main tidal channel. Fluid mud is formed near Haimen station, with tides infuencing the spatial and temporal variations in its thickness and speed. Sediment is actively exchanged among fuid mud-water-seabed, with sink and source processes dominating near the bay mouth and the Haimen station, respectively. Sediments weaken the seaward residual currents slightly by changing their viscosity and the von Karman constant, and the stratifcation process is afected by changes in water density. The fndings of this study provide a foundation for the study of material transportation in an estuarine ecosystem.

Long-term organic-inorganic fertilization ensures great soil productivity and bacterial diversity after natural-to-agricultural ecosystem conversion

Weibing Xun,Zhihui Xu,Wei Li,Yi Ren,Ting Huang,Wei Ran,Boren Wang,Qirong Shen,Ruifu Zhang 한국미생물학회 2016 The journal of microbiology Vol.54 No.9

Natural ecosystems comprise the planet’s wild plant and animal resources, but large tracts of land have been converted to agroecosystems to support the demand for agricultural products. This conversion limits the number of plant species and decreases the soil biological diversity. Here we used highthroughput 16S rRNA gene sequencing to evaluate the responses of soil bacterial communities in long-term converted and fertilized red soils (a type of Ferralic Cambisol). We observed that soil bacterial diversity was strongly affected by different types of fertilization management. Oligotrophic bacterial taxa demonstrated large relative abundances in chemically fertilized soil, whereas copiotrophic bacterial taxa were found in large relative abundances in organically fertilized and fallow management soils. Only organic-inorganic fertilization exhibited the same local taxonomic and phylogenetic diversity as that of a natural ecosystem. However, the independent use of organic or inorganic fertilizer reduced local taxonomic and phylogenetic diversity and caused biotic homogenization. This study demonstrated that the homogenization of bacterial communities caused by natural-to-agricultural ecosystem conversion can be mitigated by employing rational organic-inorganic fertilization management.

Mechanism of the dynamic pressure caused by the instability of upper chamber coal pillars in Shendong coalfield, China

Weibing Zhu,Jingmin Xu,Yingchun Li 한국지질과학협의회 2017 Geosciences Journal Vol.21 No.5

In Shendong coalfield, severe support failure accidents caused by the dynamic pressure occurred frequently when longwall faces extracting the lower coal seam progress below the chamber coal pillars. These incidents largely threaten the personnel safety and regular operations. The rationale of the dynamic pressure has been investigated based on the movement law of the overlying strata. Experimental and numerical simulations of a longwall face in Shigetai coal mine agree well with the qualitative explanations. It is shown that the failure of the chamber coal pillars causes the sudden break and even rotation of the key strata, thereby leading to strong dynamic load that crushes the supports in the longwall face. Several guidelines have been proposed to prevent the occurrence of the dynamic pressure, the capability of which has been demonstrated by in situ practice in two longwall faces in Shendong coalfield.

Effects of CaCN2 and SA on H2O2 and Activities of Antioxidant Enzymes and Dormancy-Release of Grape Bud

Weibing Jiang,Haozhang Han,Jing Cao,Gang Li 한국원예학회 2006 한국원예학회 기타간행물 Vol.- No.-

Effect of a Multi-stage Processing Method on the Composite Properties of a Stainless-Steel Surface

Jing Li,Jianan Cao,Lida Pan,Feng Du,Weibing Wang,Chengyu Xu 대한금속·재료학회 2022 METALS AND MATERIALS International Vol.28 No.4

In this study, a multi-stage sandblasting and acid-etching processing method is used to prepare a 304 stainless-steel surfacewith a loose structure that has the composite properties of superhydrophobicity, low adhesion, anti-icing ability, self-cleaningbehavior and corrosion resistance. The surface morphology and chemical constituents of this structure are characterizedby scanning electron microscopy and X-ray diffraction, respectively. The results show that the micro-scale roughness anddifferent degrees of porosity in this structure play a key role in its superhydrophobicity.The anti-icing properties and corrosionresistance are characterized by contact-angle measurements and electrochemical workstation analyses, respectively. The results show that superhydrophobicity has positive effects on surface self-cleaning, anti-icing properties and corrosionresistance of 304 stainless-steel.

Performance of Gas-Liquid Upstream Pumping Spiral Groove Mechanical Face Seals

Baoyu Zhang,Weibing Wang,Tiebo Sun,Ping Li 한국유체기계학회 2024 International journal of fluid machinery and syste Vol.17 No.1

Upstream pumping spiral grooves provides an effective way to realize design of mechanical seals with long service life as well as low leakage rate, which largely lies on precise design of spiral grooves under gas-liquid lubricating boundary conditions. The originality of this paper is to consider the gas phase pressure boundary in order to be suitable for more complex gas-liquid seal analysis. An numerical analysis of performance of upstream pumping spiral groove mechanical face seals is carried outunder gas-liquid boundary conditions. Opening force and leakage rate are calculated taking account of gas-liquid fluid medium boundary conditions as well as cavitation effect. The results show that the opening force and leakage rate decrease obviously under gas-liquid boundary conditions, compared with the full liquid boundary conditions, exceeding 50% in degree. Besides, the groove parameters such as spiral angle, slotting ratio and groove number present obvious and complex influence on the opening force and leakage rate. This research may provide the reasonable basis for the design of upstream pumping spiral groove mechanical face seals.

Analysis of Cable under Dynamic Contact and Large Deformation

Bingjian Wang,Qingbin Li,Tianyun Liu,Weibing Peng 대한토목학회 2019 KSCE JOURNAL OF CIVIL ENGINEERING Vol.23 No.4

For simulating contact interactions and high displacement gradients between the cable and the saddle at the middle tower of tripletower suspension bridges, a cable element is developed by combining the absolute nodal coordinate formulation and the quasiconforming technique. New curvature strains are developed and elastic forces are explicitly formulated for the cable elements. Thereafter, it is compared to the original one to verify its locking remedies. The numerical solutions using the element are compared to analytical results and solutions by the original element. Compared to the original, the proposed element suppresses the highfrequency disturbances in the velocity and acceleration curves. Using the element, the contact and sliding behavior between the cable and the saddle is analyzed by employing parameters obtained experimentally. The saddle’s mechanical and frictional performance subjected to different friction coefficients and unbalanced cable forces is investigated. The proposed model exhibits excellent accuracy in the prediction of the sliding force and the contact status between the cable and the saddle.

MiR-200c-3p aggravates gastric cell carcinoma via KLF6

Wang Ying,Lu Kaijuan,Li Weibing,Wang Zhigang,Ding Jing,Zhu Zeyu,Li Zhipeng 한국유전학회 2021 Genes & Genomics Vol.43 No.11

Background Gastric cell carcinoma (GCC) is a common and high-incidence malignant gastrointestinal cancer that seriously threatens human life and safety. Evidences suggest that microRNAs (miRNAs) exhibit an essential role in regulating the occurrence and development of GCC, while the efects and possible mechanisms remain to be further explored. Objective This study was designed to explore whether miR-200c-3p exerted its functional role in the growth and metastasis of GCC, and investigate the possible mechanisms. Methods The expression levels of miR-200c-3p in GCC tissues and cell lines were detected by qRT-PCR analysis. The functional role of miR-200c-3p in the viability, proliferation, migration and invasion of GCC cells were evaluated by CCK-8, EdU, wound healing and Transwell assays. In addition, the candidate targets of miR-200c-3p was predicted and confrmed by dual-luciferase reporter assay. Moreover, the relationship between miR-200c-3p and target (Krüppel like factor 6, KLF6) was assessed by qRT-PCR and western blot assays. Besides, the expression levels of KLF6 in GCC cells were determined by qRT-PCR and western blot assays. Furthermore, the role of KLF6 in the viability, proliferation, migration and invasion of GCC cells mediated with miR-200c-3p mimics was evaluated by CCK-8, EdU, wound healing and Transwell assays. Results In the present study, a new tumor promoting function of miR-200c-3p was disclosed in GCC. We found that the expression of miR-200c-3p was obviously increased in clinic GCC tissues and cell lines. In addition, down-regulation of miR-200c-3p suppressed cell viability, proliferation, migration, and invasion in GCC cells. Moreover, KLF6 was verifed as a direct target of miR-200c-3p by binding its 3’-UTR. Additionally, KLF6 was remarkably decreased and was negatively associated with the miR-200c-3p expression in GCC cell lines. Furthermore, over-expression of KLF6 retarded the efects of miR-200c-3p on the growth and metastasis of GCC cell lines. Conclusions MiR-200c-3p potentially played a tumor-promoting role in the occurrence and development of GCC, which may be achieved by targeting KLF6.

Causal relationship between smoking status, smoking frequency and bladder cancer: a Mendelian randomization study

Pang Lei,Ding Zijun,Chai Hongqiang,Li Fei,Wu Ming,Shuang Weibing 한국유전학회 2023 Genes & Genomics Vol.45 No.2

Background Smoking is a well-established risk factor for bladder cancer. However, it remained unclear that whether smoke status and smoke frequency increase bladder cancer. Objective We aim to explore the causal relationship between smoking status, smoking frequency and the risk of bladder cancer by Mendelian randomization. Methods Large sample size of the genome-wide association(GWAS) database of smoking status, smoking frequency and bladder cancer were obtained. Smoking status included never, previous and current whereas smoking frequency included cigarettes smoked per day, number of cigarettes currently smoked daily and pack years of smoking. Six sets of instrumental variables and 78 related single nucleotide polymorphic(SNP) loci were identified (P < 5 × 10–8. Linkage disequilibrium R2 < 0.001). The causal relationship between smoking status and bladder tumor was studied by inverse variance weighted (IVW), weighted median and MR-Egger regression. Sensitivity analysis were also performed. Results There is no causal effect from smoke status on bladder cancer risk while significantly positive relationship between smoking frequency on bladder cancer risk were found. IVW results showed that cigarettes smoked per day, number of cigarettes currently smoked daily and pack years of smoking increase bladder cancer (OR 1.001, 95% CI 1.000–1.002, P = 0.047; OR 1.003, 95% CI 1.000–1.005, P = 0.028; OR 1.004, 95% CI 1.001–1.006, P = 0.003). Sensitivity analysis showed that genetic pleiotropy did not bias the results. Conclusion The results of two sample Mendelian randomization analysis show that there is a positive causal relationship between smoking frequency and the risk of bladder cancer.

Belt-like VO2(M) with a rectangular cross section: A new route to prepare, the phase transition and the optical switching properties

Yifu Zhang,Meijuan Fan,Fei Niu,Weibing Wu,Chi Huang,Xinghai Liu,Houbin Li,Xin Liu 한국물리학회 2012 Current Applied Physics Vol.12 No.3

Belt-like VO2(M) with a rectangular cross section was first synthesized by the irreversible transformation of VO2(A) at the elevated temperatures under the inert atmosphere to the best of our knowledge. The asobtained samples were characterized by a combination of techniques including XRD, SEM and TEM. The processes of converting VO2(A) to VO2(M) were briefly discussed. The as-obtained VO2(M) has belt-like morphology with a rectangular cross section with typical lengths up to several tens of micrometers,widths ranging from tens of nanometers to several micrometers, and thicknesses about 60e150 nm. The morphology and size of the VO2(M) were dependent on that of the precursor VO2(A). The phase transition properties of VO2(M) were investigated by DSC, indicating that it exhibited a strong phase transition at 67.9 ℃ in the heating cycle and 61.1 ℃ in the cooling cycle. Furthermore, the optical switching property of VO2(M) was studied by the variable-temperature infrared spectra, and it was found that the as-obtained VO2(M) could be used as the optical switch.