Efficient degradation of imidacloprid in wastewater by a novel p-n heterogeneous Ag2O/BiVO4/diatomite composite under hydrogen peroxide

Jing Chen,Qifang Ren,Chunshan Xu,Bin Chen,Shaohua Chen,Yi Ding,Zhen Jin,Wanmi Guo,Xinyu Jia 한국공업화학회 2023 Journal of Industrial and Engineering Chemistry Vol.123 No.-

In this study, Ag2O/BiVO4/diatomite composite with p-n heterojunction structure was synthesized bysimple hydrothermal method with diatomite as carrier. It was found that under the action of hydrogenperoxide (H2O2), the imidacloprid (IMD) could be effectively degraded by the composite. Systemic evaluationswas conducted on effects of pH value, catalyst dosage, H2O2 concentration, initial IMD concentration,and anion on how effeciently this new photocatalytic composite can degrade IMD. The results showthat the p-n heterojunction formed between the two contact surfaces of Ag2O nanoparticle and BiVO4promotes the charge transfer between the interfaces, inhibits recombination of electrons and holes,and thus significantly improves the catalytic performance. The stability and reusability of Ag2O/BiVO4/diatomite composites were tested with ICP experiment and cyclic experiment. Active substancecapture experiment and ESR reveal the photocatalytic reaction mechanism and confirm that superoxideradical (O2), hydroxyl radical (OH), and h+ can promote the degradation of IMD. The degradation productsand the intermediates of IMD were identified through LC-MS, on a basis of which the possible transformationpathway was proposed. In situ synthesis of p-type Ag2O and n-type BiVO4 heterojunctioncomposites has opened a new direction for photocatalytic degradation of organic pollutants.

Goal-oriented multi-collision source algorithm for discrete ordinates transport calculation

Xinyu Wang,Bin Zhang,Yixue Chen 한국원자력학회 2022 Nuclear Engineering and Technology Vol.54 No.7

Discretization errors are extremely challenging conundrums of discrete ordinates calculations for radiation transport problems with void regions. In previous work, we have presented a multi-collision source method (MCS) to overcome discretization errors, but the efficiency needs to be improved. This paper proposes a goal-oriented algorithm for the MCS method to adaptively determine the partitioning of the geometry and dynamically change the angular quadrature in remaining iterations. The importance factor based on the adjoint transport calculation obtains the response function to get a problem-dependent, goal-oriented spatial decomposition. The difference in the scalar fluxes from one high-order quadrature set to a lower one provides the error estimation as a driving force behind the dynamic quadrature. The goal-oriented algorithm allows optimizing by using ray-tracing technology or high-order quadrature sets in the first few iterations and arranging the integration order of the remaining iterations from high to low. The algorithm has been implemented in the 3D transport code ARES and was tested on the Kobayashi benchmarks. The numerical results show a reduction in computation time on these problems for the same desired level of accuracy as compared to the standard ARES code, and it has clear advantages over the traditional MCS method in solving radiation transport problems with reflective boundary conditions

Mechanism of gastrointestinal adaptability and antioxidant function of infant-derived Lactobacillus plantarum BF_15 through genomics

Xinyu Wang,Na Zhang,Dongyao Li,Miaoshu Wang,Chen Li,Hongtao Tian 한국식품과학회 2022 Food Science and Biotechnology Vol.31 No.11

Lactobacillus plantarum is an essential probiotic in the human gastrointestinal tract. L. plantarum BF_15, a functional probiotic isolated from the feces of breast-fed infants, has been reported in many in vitro and in vivo studies with strong gastrointestinal adaptability and outstanding anti-oxidative activities. Therefore, the whole genome of L. plantarum BF_15 was sequenced. Several genes, encoding the gastrointestinal adaptability-related proteins, were identified, including genes related to gastrointestinal environment-induced stress resistance, adhesive performance, and ability to transport and metabolize resistant starch and oligosaccharides. Genes related to alleviating oxidative stress were also found. Further functional verification was carried out by RT-qPCR on the 10 and 12 key adhesion and antioxidant genes. Overall, this study might provide a critical basis for L. plantarum BF_15 as a potential candidate for probiotics.

Experimental Studies on Scramjet Tested in a Freejet Facility

Xinyu Chang,Lihong Chen,Hongbin Gu,Gong Yu 한국추진공학회 2004 한국추진공학회 학술대회논문집 Vol.2004 No.5

The associations of job strain and leisure-time physical activity with the risk of hypertension: the population-based Midlife in the United States cohort study

Xinyue Liu,Timothy A. Matthews,Liwei Chen,Jian Li 한국역학회 2022 Epidemiology and Health Vol.44 No.-

OBJECTIVES Job strain is positively associated with incident hypertension, while increasing leisure-time physical activity (LTPA) can reduce incident hypertension. However, the joint associations of job strain and LTPA with incident hypertension among United States workers have yet to be investigated. This study examined the independent and joint associations of job strain and LTPA with incident hypertension. METHODS This prospective cohort study (n=1,160) utilized data from the population-based Midlife in the United States study. The associations of job strain and LTPA at baseline with incident hypertension during follow-up were examined using Cox proportional hazards models. High job strain was derived from a combination of high job demands and low job control, and high LTPA was defined as engagement in moderate or vigorous LTPA at least once per week. RESULTS During 9,218 person-years of follow-up, the hypertension incidence rate was 30.6 (95% confidence interval [CI], 27.3 to 34.3) per 1,000 person-years. High job strain was associated with a higher risk for hypertension than low job strain (adjusted hazard ratio [aHR], 1.29; 95% CI, 1.00 to 1.67). High LTPA was associated with lower hypertension risk than low LTPA (aHR, 0.77; 95% CI, 0.60 to 0.98). Hypertension risk was higher among workers with high job strain and low LTPA than among those with low job strain and high LTPA (aHR, 1.70; 95% CI, 1.18 to 2.43). CONCLUSIONS Job strain and LTPA showed positive and inverse associations, respectively, with incident hypertension. The combination of high job strain and low LTPA was associated with the highest risk for hypertension.

Bimodal-Structured Al–Mg Alloy with High Strength and Ductility Processed by High Strain Rate Rolling at Medium Temperature

Xinyu Li,Weijun Xia,Jihua Chen,Hongge Yan,Zhenzhen Li,Bin Su,Min Song 대한금속·재료학회 2021 METALS AND MATERIALS International Vol.27 No.12

A bimodal grain distribution is generated in the Al-6.5Mg alloy deformed by high strain rate rolling (HSRR) at 320 °C, inwhich the fine grains with the average size of 2.1 μm and the coarse grains with the size of hundreds of microns containingultrafine sub-grains are developed. The deformed microstructures are detected by transmission electron microscopy, X-raydiffraction and electron backscattered diffraction. High strength and considerable ductility are achieved in the HSRRed alloyand the high strength is ascribed to solution strengthening, grain (sub-grain) strengthening and dislocation strengthening. The grain (sub-grain) strengthening is the dominant contributor (~ 146 ± 6 MPa) for yield strength. The generation of newfine grains is primarily observed along the deformation bands related to the high Mg solid content and the high strain rate at320 °C. The dynamic recrystallization related to the deformation bands is proposed to build the bimodal grain distributionfor achieving high strength and considerable ductility.

SIMULATING TIRE INFLATION PRESSURE LOSS RATE TEST BY THE IDEAL MATERIAL METHOD

Chen Liang,Xinyu Zhu,Changda Li,Guolin Wang,Liu Ji 한국자동차공학회 2019 International journal of automotive technology Vol.20 No.4

Tire Inflation Pressure Loss Rate (IPLR) test is a widely accepted test method to evaluate the tire pressure retention performance, which helps increase fuel economy and prevent premature tire failures. At present, an IPLR test usually lasts for several months, which greatly reduces the efficiency of relevant research. Several analytical models are available to estimate the IPLR value, however, it mainly considers the gauge and permeability of innerliner, ignoring the effect of other components and detailed tire structure. In order to perform a thorough study of tire pressure loss process, a finite element model was developed with the material input of both mechanical and permeability properties of various rubber compounds and tire geometry input. A creative method, ideal material method, was proposed to describe the transient pressure loss process. Through this solution, a finite element model of Passenger Car Radial tire is established to predict IPLR, with a difference from the experimental result less than 5 %. Based on the model, air diffusion path in the tire is studied to better understand the process, which explains the bubble location in tire immersion tests. The effect of innerliner parameters, including halobutyl content, gauge and ending length of innerliner, on IPLR has been investigated based on simulation models.

Study on bond behavior of steel reinforced high strength concrete after high temperatures

Chen, Zongping,Zhou, Ji,Wang, Xinyue Techno-Press 2020 Advances in concrete construction Vol.10 No.2

This paper presents experimental results on bond-slip behavior of steel reinforced high-strength concrete (SRHC) after exposure to elevated temperatures. Three parameters were considered in this test: (a) high temperatures (i.e., 20℃, 200℃, 400℃, 600℃, 800℃); (b) concrete strength (i.e., C60, C70, C80); (c) anchorage length (i.e., 250 mm, 400 mm). A total of 17 SRHC specimens subjected to high temperatures were designed for push out test. The load-slip curves at the loading end and free end were obtained, the influence of various variation parameters on the ultimate bond strength and residual bond strength was analyzed, in addition, the influence of elevated temperatures on the invalidation mechanism was researched in details. Test results show that the shapes of load-slip curves at loading ends and free ends are similar. The ultimate bond strength and residual bond strength of SRHC decrease first and then recover partly with the temperature increasing. The bond strength is proportional to the concrete strength, and the bond strength is proportional to the anchoring length when the temperature is low, while the opposite situation occurs when the temperature is high. What's more, the bond damage of specimens with lower temperature develops earlier and faster than the specimens with higher temperature. From these experimental findings, the bond-slip constitutive formula of SRHC subjected to elevated temperatures is proposed, which fills well with test data.

Left-Dominant Arrhythmogenic Cardiomyopathy: A Rare and Frequently Misdiagnosed Cardiomyopathy Associated with Heart Failure

Chen Cui,Xinyu Wang,Shihua Zhao 아시아심장혈관영상의학회 2020 Cardiovascular Imaging Asia Vol.4 No.3

A 35-year-old male with 7-year history of exertional dyspnea and abdominal distention had frequent premature ventricular contractions detected by Holter monitoring. Cardiovascular magnetic resonance (CMR) imaging demonstrated a significantly dilated left ventricle (LV) with severely reduced global systolic function. Coronary arterial stenosis was excluded with CT coronary angiography. However, transmural late gadolinium enhancement was detected by CMR in the lateral wall of the LV. The patient received cardiac transplantation. The diagnosis of left dominant arrhythmogenic right ventricular cardiomyopathy was made.

Vortex-Induced Vibration Characteristics and Equivalent Static Force Calculation Method of Circular Steel Hangers on Arch Bridge

Xinyu Xu,Yingliang Wang,Xingyu Chen,Xiaolong Zheng,Yongping Zeng 대한토목학회 2020 KSCE JOURNAL OF CIVIL ENGINEERING Vol.24 No.4

In order to study the vortex-induced vibration (VIV) characteristics and equivalent static force calculation method of circular steel hangers on the arch bridge, a numerical simulation model of VIV was established using FLUENT software, and the reliability of the model was verified by wind tunnel tests. Effects of wind speed, damping ratio, initial tension and slenderness ratio on the VIV characteristics of circular steel hanger were investigated. Furthermore, the equivalent static force calculation formula and loading range of hanger considering VIV were presented. The results show that with the hanger’s damping ratio decreasing, the maximum amplitude and the lock-in wind speed range increases gradually, while the wind speed and frequency of VIV at the maximum amplitude were not significantly affected. As the initial tension increases or the slenderness ratio decreases, the frequency of VIV increases, and the wind speed corresponding to the maximum amplitude increases, however the maximum vibration amplitude has few changes. Based on a number of numerical analyses on VIV characteristics of hangers, the equivalent static force calculation method is put forward. The equivalent static force calculation method could provide a reference for the design and static analysis of the circular steel hangers.