33 results on '"Zhongjun Wan"'
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2. Spike-based adenovirus vectored COVID-19 vaccine does not aggravate heart damage after ischemic injury in mice
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Shanshan Gu, Zhongyan Chen, Xiangfu Meng, Ge Liu, He Xu, Liying Huang, Linwei Wu, Jixing Gong, Ding Chen, Bingqing Xue, Lihang Zhu, Zhongjun Wan, Jianqing Lin, Xiaolong Cai, Xiaoyan Zhang, Jia Wang, Donghui Zhang, and Nan Cao
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Biology (General) ,QH301-705.5 - Abstract
The safety of spike-based adenovirus type-5 vectored COVID-19 vaccine is evaluated, showing it neither affects the survival and function of human cardiac cells and engineered heart tissues nor aggravates heart damage in mice after ischemic injury.
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- 2022
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3. Dual-Wavelength Spectrum-Shaped Mid-Infrared Pulses and Steering High-Harmonic Generation in Solids
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Linzhen He, Weizhe Wang, Kan Tian, Maoxing Xiang, Zhongjun Wan, Bo Hu, Yang Li, Han Wu, Zi-Yu Chen, Fan Yang, and Houkun Liang
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Physics ,QC1-999 ,Applied optics. Photonics ,TA1501-1820 - Abstract
Mid-infrared (MIR) ultra-short pulses with multiple spectral-band coverage and good freedom in spectral and temporal shaping are desired by broad applications such as steering strong-field ionization, investigating bound-electron dynamics, and minimally invasive tissue ablation. However, the existing methods of light transient generation lack freedom in spectral tuning and require sophisticated apparatus for complicated phase and noise control. Here, with both numerical analysis and experimental demonstration, we report the first attempt, to the best our knowledge, at generating MIR pulses with dual-wavelength spectral shaping and exceptional freedom of tunability in both the lasing wavelength and relative spectral amplitudes, based on a relatively simple and compact apparatus compared to traditional pulse synthesizers. The proof-of-concept demonstration in steering the high-harmonic generation in a polycrystalline ZnSe plate is facilitated by dual-wavelength MIR pulses shaped in both spectral and temporal domains, spanning from 5.6 to 11.4 μm, with multi-microjoule pulse energy and hundred- milliwatt average power. Multisets of harmonics corresponding to different fundamental wavelengths are simultaneously generated in the deep ultraviolet region, and both the relative strength of individual harmonics sets and the spectral shapes of harmonics are harnessed with remarkable freedom and flexibility. This work would open new possibilities in exploring femtosecond control of electron dynamics and light–matter interaction in composite molecular systems.
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- 2023
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4. Simple, stable and efficient nonlinear pulse compression through cascaded filamentation in air
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Tao Pu, Kan Tian, Bo Hu, Zhongjun Wan, Linzhen He, Xuemei Yang, Han Wu, Yang Li, Weizhe Wang, and Houkun Liang
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femtosecond pulse ,filamentation ,nonlinear compression ,Applied optics. Photonics ,TA1501-1820 - Abstract
Nonlinear compression has become an obligatory technique along with the development of ultrafast lasers in generating ultrashort pulses with narrow pulse widths and high peak power. In particular, techniques of nonlinear compression have experienced a rapid progress as ytterbium (Yb)-doped lasers with pulse widths in the range from hundreds of femtoseconds to a few picoseconds have become mainstream laser tools for both scientific and industrial applications. Here, we report a simple and stable nonlinear pulse compression technique with high efficiency through cascaded filamentation in air followed by dispersion compensation. Pulses at a center wavelength of 1040 nm with millijoule pulse energy and 160 fs pulse width from a high-power Yb:CaAlGdO4 regenerative amplifier are compressed to 32 fs, with only 2.4% loss from the filamentation process. The compressed pulse has a stable output power with a root-mean-square variation of 0.2% over 1 hour.
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- 2023
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5. Investigating and Resolving Cardiotoxicity Induced by COVID‐19 Treatments using Human Pluripotent Stem Cell‐Derived Cardiomyocytes and Engineered Heart Tissues
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He Xu, Ge Liu, Jixing Gong, Ying Zhang, Shanshan Gu, Zhongjun Wan, Pengcheng Yang, Yage Nie, Yinghan Wang, Zhan‐peng Huang, Guanzheng Luo, Zhongyan Chen, Donghui Zhang, and Nan Cao
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cardiotoxicity ,engineered heart tissue ,high throughput screening ,human pluripotent stem cell‐derived cardiomyocytes ,repurposed drugs for COVID‐19 ,Science - Abstract
Abstract Coronavirus disease 2019 continues to spread worldwide. Given the urgent need for effective treatments, many clinical trials are ongoing through repurposing approved drugs. However, clinical data regarding the cardiotoxicity of these drugs are limited. Human pluripotent stem cell‐derived cardiomyocytes (hCMs) represent a powerful tool for assessing drug‐induced cardiotoxicity. Here, by using hCMs, it is demonstrated that four antiviral drugs, namely, apilimod, remdesivir, ritonavir, and lopinavir, exhibit cardiotoxicity in terms of inducing cell death, sarcomere disarray, and dysregulation of calcium handling and contraction, at clinically relevant concentrations. Human engineered heart tissue (hEHT) model is used to further evaluate the cardiotoxic effects of these drugs and it is found that they weaken hEHT contractile function. RNA‐seq analysis reveals that the expression of genes that regulate cardiomyocyte function, such as sarcomere organization (TNNT2, MYH6) and ion homeostasis (ATP2A2, HCN4), is significantly altered after drug treatments. Using high‐throughput screening of approved drugs, it is found that ceftiofur hydrochloride, astaxanthin, and quetiapine fumarate can ameliorate the cardiotoxicity of remdesivir, with astaxanthin being the most prominent one. These results warrant caution and careful monitoring when prescribing these therapies in patients and provide drug candidates to limit remdesivir‐induced cardiotoxicity.
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- 2022
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6. Glycyrrhizin Protects Mice Against Experimental Autoimmune Encephalomyelitis by Inhibiting High-Mobility Group Box 1 (HMGB1) Expression and Neuronal HMGB1 Release
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Yan Sun, Huoying Chen, Jiapei Dai, Zhongjun Wan, Ping Xiong, Yong Xu, Zhengrong Han, Weitai Chai, Feili Gong, and Fang Zheng
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high-mobility group box 1 ,experimental autoimmune encephalomyelitis ,multiple sclerosis ,glycyrrhizin ,neurons ,Immunologic diseases. Allergy ,RC581-607 - Abstract
The inflammatory mediator high-mobility group box 1 (HMGB1) plays a critical role in the pathogenesis of human multiple sclerosis (MS) and mouse experimental autoimmune encephalomyelitis (EAE). Glycyrrhizin (GL), a glycoconjugated triterpene extracted from licorice root, has the ability to inhibit the functions of HMGB1; however, GL’s function against EAE has not been thoroughly characterized to date. To determine the benefit of GL as a modulator of neuroinflammation, we used an in vivo study to examine GL’s effect on EAE along with primary cultured cortical neurons to study the GL effect on HMGB1 release. Treatment of EAE mice with GL from onset to the peak stage of disease resulted in marked attenuation of EAE severity, reduced inflammatory cell infiltration and demyelination, decreased tumor necrosis factor-alpha (TNF-α), IFN-γ, IL-17A, IL-6, and transforming growth factor-beta 1, and increased IL-4 both in serum and spinal cord homogenate. Moreover, HMGB1 levels in different body fluids were reduced, accompanied by a decrease in neuronal damage, activated astrocytes and microglia, as well as HMGB1-positive astrocytes and microglia. GL significantly reversed HMGB1 release into the medium induced by TNF-α stimulation in primary cultured cortical neurons. Taken together, the results indicate that GL has a strong neuroprotective effect on EAE mice by reducing HMGB1 expression and release and thus can be used to treat central nervous system inflammatory diseases, such as MS.
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- 2018
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7. MTCS-Net: A Novel Framework for Non-invasive Myocardial Tissue Quantitative Measurement and Instance Segmentation.
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Yuqiang Zhang, Yuying Li, Yang Yang, Donghui Zhang, Jixing Gong, Xiangfu Meng, Zhongjun Wan, and Shanqing Gao
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- 2024
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8. Research on Cooperation Incentives for Emergency Logistics Capacity Reserve from Humanitarian Organization Perspective
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Zhongjun Wan
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Recently, catastrophic events have occurred frequently, seriously threatening the safety of people's lives and property. The uncertainty in the demand for emergency logistics resources poses a huge challenge for emergency stockpiling. From the perspective of humanitarian organizations, cooperation with third-party logistics providers for emergency logistics capacity reserve can improve the efficiency and reduce the cost of reserve. However, in practice, there is a lack of unity of purpose, capacity mismatch and information asymmetry between the two rescue parties, which makes cooperative emergency reserve a problem worth studying. This paper addresses the emergency logistics capacity reserve problem and take a two-level supply chain consisting of humanitarian organization and third-party logistics provider as the research object to explore the cooperative reserve model between the two sides. This paper establishes a Stackelberg game model with humanitarian organization as the leader and third-party logistics provider as the follower based on the premise of mutual cooperation. Under different incentive models of cooperation, the humanitarian organization executes the price decision to minimize the deprivation cost and disaster relief cost, and the third-party logistics provider executes the stockpiling decision to maximize the revenue. Secondly, this paper discusses the equilibrium decisions of both sides of the game under different scenarios and provides corresponding numerical analysis. Finally, this paper finds that for the possible moral hazard problem of third-party logistics provider, humanitarian organization incentives and government subsidies have a positive effect on third-party logistics provider's stockpiling; while the effect of corporate reputation depends on their donation behavior.
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- 2023
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9. Micropatterned Hydrogels with Highly Ordered Cellulose Nanocrystals for Visually Monitoring Cardiomyocytes
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Junmei Wang, Qian Liu, Jixing Gong, Zhongjun Wan, Jinping Zhou, Chunyu Chang, and Donghui Zhang
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Biomaterials ,Gelatin ,Nanoparticles ,General Materials Science ,Hydrogels ,Myocytes, Cardiac ,General Chemistry ,Cellulose ,Biotechnology - Abstract
Cardiac microphysiological systems are accurate in vitro platforms that reveal the biological mechanisms underlying cardiopathy, accelerating pharmaceutical research in this field. Current cardiac microphysiological devices and organs-on-chips consist of several layers prepared with complex, multi-step processes. Incorporating inorganic photonic crystals may cause long-term biocompatibility issues. Herein, micropatterned hydrogels with anisotropic structural colors are prepared by locking shear-oriented tunicate cellulose nanocrystals (TCNCs) in hydrogel networks through in situ polymerization, allowing the visualization and monitoring of cardiomyocytes. The anisotropic hydrogels are composed of highly ordered TCNCs with bright interference color and micro-grooved methacrylated gelatin with excellent biocompatibility. The microgroove patterns induce cardiomyocyte alignment and the autonomous beating of cardiomyocytes causes the hydrogels to deform, dynamically shifting the interference color. These micropatterned hydrogels could noninvasively monitor real-time changes of cardiomyocytes under pharmaceutical treatment and electrical stimulation through wavelength shifts in the transmittance spectra. This system provides a new way to detect the beat rate of cardiac tissue and it may contribute to high throughput develop.
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- 2022
10. Simulation and experiment on improving NOX conversion efficiency of ship selective catalytic reduction system
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Zhijun Chen, Zhi Li, Xiayi Hu, Zhongjun Wang, Hongyun Yang, Eman Ramadan Elsharkawy, Salah M. El-Bahy, Mengmeng Wu, Mingmao Hu, and Zhanhu Guo
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Marine SCR Technology ,Denitrification Efficiency ,SCR structure parameters ,SCR operating parameters ,Engineering (General). Civil engineering (General) ,TA1-2040 - Abstract
Selective catalytic reduction (SCR) technology is the main means of reducing NOX emissions. Urea injection structure parameters (i.e., the hole number in a nozzle, spray angle, the distance between the nozzle and the front section of the catalyst) and operating parameters (i.e., exhaust gas temperature, gas hourly space velocity, ammonia-to-nitrogen ratio (ANR)) of the SCR systems have a significant impact on denitrification efficiency (deNOX). A three-dimensional simulation model is developed to investigate the impact of diverse parameters on deNOX. The influence of temperature, ANR and space velocity on the deNOX of SCR system is studied by using the control variable method. The simulation model is modified according to the SCR catalyst gas distribution test results. A diesel bench experiment is conducted to test the deNOX of the SCR system of D2 cycle and two additional operating points to verify the accuracy of the numerical simulation model. Based on this model, the influence of key factors on the deNOX of SCR system is studied. In SCR system, the optimal urea injection angle is about 75°, the optimal number of nozzle holes is 4, the distance between the optimal urea injection point and the front section of the catalyst is 8 times of the pipe diameter, and the optimal operating temperature is 300 ∼ 420℃. The influence trend of ANR on deNOX at different temperatures is obtained. This provides a theoretical support for the realization of SCR system in the future.
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- 2024
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11. Impact of cascade reservoir on the sources of organic matter in sediments of Lancang river
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Yufei Bao, Meng Sun, Yuchun Wang, Ji Lu, Yajie Wu, Hao Chen, Shanze Li, Yong Qin, Zhuowei Wang, Jie Wen, Xinghua Wu, and Zhongjun Wang
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Earth sciences ,Earth-surface processes ,Earth surface sediment transport ,Hydrology ,Soil hydrology ,Science - Abstract
Summary: The construction of dams to intercept natural rivers constitutes the most severe human activity influencing the underlying surface. This study focuses on four cascade reservoirs of the Lancang River and explores their impact on the migration of organic matter in sediments. The research reveals significant spatial variations in total organic carbon (TOC) and total nitrogen concentrations in the sediments of the four reservoirs. The carbon and nitrogen isotopes indicate that terrigenous organic matter is the main source of TOC in the sediments, contributing an average of 66.80%. Endogenous algal-derived organic matter is the second significant source, contributing between 14.30% and 32.91%. The sources contributed from upstream organic matter are the lowest, ranging from 6.36% to 15.33%. Our study demonstrates that the construction of cascade reservoirs may significantly alter the processes of material sources in the river basin ecosystem, particularly in the large reservoir which increased more endogenous algal-derived organic matter.
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- 2025
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12. Incidence and risk factors of hepatitis E virus infection in women with gynecological tumors in Eastern China
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Wenye Bai, Xiao Wu, Shuchao Zhao, Yang Yu, Zhongjun Wang, Xiu Li, and Na Zhou
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Hepatitis E virus ,Gynecological tumor ,Seroprevalence ,Eastern China ,Risk factors ,Medicine ,Biology (General) ,QH301-705.5 - Abstract
Background Recently, there has been increasing interest in the exploration of the association between the hepatitis E virus (HEV) infection and malignancies; however, epidemiological data for HEV infection among women with a gynecological tumors (GT) are limited. Herein, we investigated the correlation between HEV and GT in Chinese women. Methods We recruited 452 women diagnosed with a primary GT and 452 healthy volunteers to investigate the possible routes and risk factors for HEV infection. The serum antibody levels of anti-HEV IgG and IgM were measured by enzyme-linked immunoassays once a year. Results After a median follow-up time of 5.4 years (range 4 to 7 years), the overall detection rate of anti-HEV antibodies in patients with GT and in controls were 69/452 (15.27%) and 23/452 (5.09%) (P = 0.001), respectively. The seroprevalence of anti-HEV IgG antibodies was significant higher in patients with GT (15.27%) than in healthy controls (5.09%) (P = 0.001). Moreover, 13 (2.88%) patients with GT were positive for IgM antibodies, while only 4 (0.88%) healthy controls tested positive for anti-HEV IgM antibodies (P = 0.028). The highest prevalence of HEV antibodies were detected in patients with ovarian borderline tumors (40%), followed by patients with ovarian cancer (20.54%) and endometrial cancer (18.46%). Multivariable analysis revealed that contact with dogs (OR, 1.88; 95% CI [1.10–3.22]; P = 0.015) and a history of anti-tumor chemotherapy (OR, 1.85; 95% CI [1.07–3.20]; P = 0.028) were independent risk factors for HEV infection. Conclusion Overall, the present study showed that patients with GT are more susceptible to HEV infection in Eastern China, particularly in patients with ovarian borderline tumors. Thus, effective strategies are needed to reduce HEV infection in patients with GT.
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- 2024
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13. An experimental and modeling study of ethylene–air combustion over a wide temperature range
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Ningxin Tan, Xiang-Yuan Li, Changhua Zhang, Mo Yang, Jing-Bo Wang, and Zhongjun Wan
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Premixed flame ,Materials science ,Ethylene ,Laminar flame speed ,020209 energy ,General Chemical Engineering ,General Physics and Astronomy ,Energy Engineering and Power Technology ,Thermodynamics ,02 engineering and technology ,General Chemistry ,Atmospheric temperature range ,Combustion ,law.invention ,Ignition system ,chemistry.chemical_compound ,Fuel Technology ,020401 chemical engineering ,chemistry ,law ,0202 electrical engineering, electronic engineering, information engineering ,0204 chemical engineering ,Shock tube ,Pyrolysis - Abstract
Ethylene is an important intermediate during oxidation and pyrolysis process of higher hydrocarbons, and also serves as a fuel under practical engines. An experimental and modeling study is performed to investigate the combustion chemistry of ethylene–air mixtures under a wide range of conditions. The shock tube experiments are conducted at pressures of 1, 4, 10 and 19 atm with equivalence ratios of 0.5, 1.0 and 2.0 to determine the ignition delay times by measuring the emission signal of excited methylidyne (CH*). The ignition data under 10 and 19 atm both span a wide temperature range varying from a low temperature of 721 K to a high temperature of 1320 K. No typical negative-temperature-coefficient is observed, but the ignition at low temperatures is much shorter than the extrapolation at high temperatures. Simulations are performed and compared to the experiments using contemporary core models with consideration of a linear pressure rise of 3% /ms, but no simulation could predict the ignition trend under low-to-intermediate temperatures. Therefore, a detailed model of ethylene oxidation is proposed based on AramcoMech2.0 in the present work. The modeling behavior at high temperatures is improved by revision of addition reaction between ethylene and oxygen atom (C2H4+Ӧ). The modeling behavior at the region of low-to-intermediate temperatures is improved by detailed updating of β-hydroxyethyl oxidation (PĊ2H4OH+O2). The effect of reactions at the potential energy surface of C2H4+HȮ2 and Ċ2H5+O2 is determined, and the second oxygen addition (Ċ2H4OOH+O2) is added into current model. The present model is extensively validated by ignition delay times, concentration profiles of stable species in jet-stirred reactors and laminar flame speed under various test conditions. Sensitivity analyses are carried out to identify the dominant reactions during the auto-ignition process and laminar premixed flame propagation. Additional simulations are performed to investigate the effect of model modifications on predictions of ethane and ethanol oxidation. The present model slightly promotes the low-temperature ignition of both ethane and ethanol, and its prediction on the concentration profiles of some stable species is also improved. The proposed model of ethylene oxidation can be used as a cornerstone to develop models of larger hydrocarbon fuels.
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- 2020
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14. Experimental and kinetic study of the effects of n-butanol addition on toluene reference fuel auto-ignition
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Zhongjun Wan, Lei Shi, Dongdong Chen, Ping Li, and Changhua Zhang
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Fuel Technology ,General Chemical Engineering ,Organic Chemistry ,Energy Engineering and Power Technology - Published
- 2023
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15. Ultrabroad (3.7–17 µm) tunable femtosecond optical parametric amplifier based on BaGa4Se7 crystal
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Kan Tian, Weizhe Wang, Chunxiao Li, Zhongjun Wan, Bo Hu, Linzhen He, Maoxing Xiang, Jiyong Yao, Han Wu, and Houkun Liang
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Atomic and Molecular Physics, and Optics - Abstract
We demonstrate the first (to the best of our knowledge) tunable femtosecond (fs) mid-infrared (MIR) optical parametric amplifier (OPA) based on BaGa4Se7 (BGSe) crystal with an ultra-broadband spectral range. Benefiting from the broad transparency range, high nonlinearity, and relatively large bandgap of BGSe, the MIR OPA pumped at 1030 nm with a repetition of 50 kHz has an output spectrum that is tunable across an extremely wide spectral range spanning from 3.7 to 17 µm. The maximum output power of the MIR laser source is measured as 10 mW at a center wavelength of 16 µm, corresponding to a quantum conversion efficiency of 5%. Power scaling is straightforwardly achieved by using a stronger pump in BGSe with an available large aperture size. A pulse width of 290 fs centered at 16 µm is supported by the BGSe OPA. Our experimental result indicates that BGSe crystal could serve as a promising nonlinear crystal for fs MIR generation with an ultra-broadband tuning spectral range via parametric downconversion for applications such as MIR ultrafast spectroscopy.
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- 2022
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16. A Shock Tube Study of Ethylene/Air Ignition Characteristics over a Wide Temperature Range
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Yijun Wang, Dexiang Zhang, Ping Li, Zhongjun Wan, Changhua Zhang, and Zujun Zheng
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Materials science ,Ethylene ,020209 energy ,General Chemical Engineering ,General Physics and Astronomy ,Energy Engineering and Power Technology ,02 engineering and technology ,General Chemistry ,Atmospheric temperature range ,Combustion ,01 natural sciences ,Intermediate product ,010305 fluids & plasmas ,law.invention ,Ignition system ,chemistry.chemical_compound ,Fuel Technology ,chemistry ,Chemical engineering ,law ,0103 physical sciences ,0202 electrical engineering, electronic engineering, information engineering ,Shock tube - Abstract
As a key intermediate product, ethylene plays an important role in the combustion of heavy hydrocarbons. Very limited experiments have focused on the high temperature (>1000 K) ethylene ignition at...
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- 2019
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17. Study ofn-Butylcyclohexane/Air Ignition over a Broad Range of Temperatures in Shock Tube
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Yijun Wang, Changhua Zhang, Dexiang Zhang, Zhongjun Wan, and Ping Li
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Materials science ,020209 energy ,General Chemical Engineering ,General Physics and Astronomy ,Energy Engineering and Power Technology ,02 engineering and technology ,General Chemistry ,Mechanics ,Ignition delay ,01 natural sciences ,010305 fluids & plasmas ,law.invention ,Ignition system ,Fuel Technology ,law ,0103 physical sciences ,0202 electrical engineering, electronic engineering, information engineering ,Shock tube ,Equivalence (measure theory) - Abstract
Measurements of ignition delay times for n-butylcyclohexane/air were performed over temperatures of 707–1458 K, pressures of 2.0, 5.0, and 15.0 atm, and equivalence ratios of 0.5, 1.0, and 2.0 in a...
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- 2019
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18. Ad5-spike COVID-19 vaccine does not aggravate heart damage after ischemic injury
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Donghui Zhang, Nan Cao, Linwei Wu, Xiaolong Cai, Xiangfu Meng, Zhongjun Wan, Ge Liu, Jia Wang, Jixing Gong, Xiaoyan Zhang, He Xu, Ding Chen, Liying Huang, Zhongyan Chen, Lihang Zhu, Shanshan Gu, and Bingqing Xue
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medicine.medical_specialty ,Text mining ,Coronavirus disease 2019 (COVID-19) ,business.industry ,Internal medicine ,Cardiology ,Medicine ,Spike (software development) ,Ischemic injury ,business ,hormones, hormone substitutes, and hormone antagonists ,Heart damage - Abstract
Hopes for a COVID-19 vaccine are now a reality. The spike protein of SARS-CoV-2, which majorly binds to the host receptor ACE2 for cell entry, is used by most of the COVID-19 vaccine candidates as a choice of antigen. ACE2 is highly expressed in the heart and is known to be protective in multiple organs. Interaction of spike with ACE2 has been reported to reduce ACE2 expression and affect ACE2-mediated signal transduction in the heart. However, whether a spike-encoding vaccine will aggravate myocardial damage after a heart attack via affecting ACE2 remains unclear. Therefore, for patients with or at risk of heart diseases, questions arise around the safety of the spike-based vaccines. Here, we demonstrate that ACE2 is up-regulated and protective in the injured mouse heart after myocardial ischemia/reperfusion (I/R). Infecting human cardiomyocyte, smooth muscle cells, endothelial cells, and cardiac fibroblasts with a recombinant adenovirus type-5 vectored COVID-19 vaccine expressing the spike protein (AdSpike) does not affect cell survival and cardiomyocyte function, whether the cells are subjected to hypoxia-reoxygenation injury or not. This observation is further confirmed in human engineered heart tissues. Furthermore, AdSpike vaccination does not aggravate heart damage in wild-type or humanized ACE2 mice after I/R injury, even at a dose that is ten-fold higher as used in human. This study represents the first systematic evaluation of the safety of a leading COVID-19 vaccine under a disease context and may provide important information to ensure maximal protection from COVID-19 in patients with or at risk of heart diseases.
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- 2021
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19. Fault Diagnosis of Wastewater Treatment Processes Based on CPSO-DKPCA
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Baochang Xu, Peng Zhuang, Yaxin Wang, Wei He, Zhongjun Wang, and Zhongyao Liu
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Fault diagnosis ,Wastewater treatment ,Dynamic kernel principal component analysis ,Chaotic particle swarm optimization ,Granger causality analysis ,Electronic computers. Computer science ,QA75.5-76.95 - Abstract
Abstract The wastewater treatment process (WWTP) is one of the most common links in chemical plants. However, the testing for diagnosing faults in wastewater treatment plants is expensive and time-consuming. Due to strong nonlinearity and variable autocorrelation, traditional WWTP diagnostic methods based on principal component analysis (PCA) can lead to low fault detection rates (FDR) or difficulty in determining the root cause of faults. In this paper, an improved dynamic kernel principal component analysis (DKPCA) and Granger causality (GC) analysis model that uses chaotic particle swarm optimization (CPSO) to detect WWTP and locate the root causes of faults is proposed. First, a kernel function is introduced to map a nonlinear matrix to a linear space. Then, the training data are extended through a time lag constant to solve the problem of nonlinear and variable autocorrelation in WWTP. Moreover, a novel fault candidate variables selection method, together with GC, is introduced to locate the root variables of the fault. The CPSO algorithm is employed to optimize DKPCA's kernel function parameters, enhancing the accuracy of fault monitoring and diagnosis models. Compared with traditional methods, the proposed method has a better fault detection rate, achieving 95.83% and 93.33% fault detection rates in simulated and real WWTP, respectively.
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- 2024
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20. Efficacy and safety of tart cherry supplementary citrate mixture on gout patients: a prospective, randomized, controlled study
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Can Wang, Wenyan Sun, Nicola Dalbeth, Zhongjun Wang, Xuefeng Wang, Xiaopeng Ji, Xiaomei Xue, Lin Han, Lingling Cui, Xinde Li, Zhen Liu, Aichang Ji, Yuwei He, Mingshu Sun, and Changgui Li
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Gout ,Urine alkalization ,Sodium bicarbonate ,Citrate ,Tart cherry ,Diseases of the musculoskeletal system ,RC925-935 - Abstract
Abstract Background Low urine pH, which may be mediated by metabolic syndrome (MetS), is common in gout. Tart cherries are shown to improve MetS symptoms and possess anti-inflammatory properties. However, the efficacy of tart cherry supplements on urine pH has yet to be studied. Objectives This study aimed to investigate the efficacy and safety of tart cherry supplementary citrate (TaCCi) mixture on urine pH, serum urate (sUA), C-reactive protein (CRP), and gout flares in gout patients initiating urate-lowering therapy (ULT), in comparison to citrate mixture and sodium bicarbonate. Methods A prospective, randomized (1:1:1), open-label, parallel-controlled trial was conducted among 282 men with gout and fasting urine pH ≤ 6, who were initiating ULT with febuxostat (initially 20 mg daily, escalating to 40 mg daily if serum urate ≥ 360 μmol/L). Participants were randomized to groups taking either sodium bicarbonate, citrate mixture, or TaCCi mixture. All participants were followed every 4 weeks until week 12. Urine pH and sUA were co-primary outcomes, with various biochemical and clinical secondary endpoints. Results Urine pH increased to a similar extent in all three groups. SUA levels declined in all three groups as well, with no significant differences observed between the groups. At week 12, the TaCCi mixture group exhibited a greater reduction in the urine albumin/creatinine ratio (UACR) compared to the other two groups (p
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- 2023
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21. Multi–Scenario Prediction of Land Cover Changes and Habitat Quality Based on the FLUS–InVEST Model in Beijing
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Xiaoyu Zhu, Zhongjun Wang, Tianci Gu, and Yujun Zhang
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habitat quality ,CA–Markov ,FLUS ,InVEST ,multi–scenario prediction ,Beijing ,Agriculture - Abstract
As urbanization accelerates worldwide, understanding the impact of urban expansion on habitat quality has become increasingly critical in environmental science research. This study examines the impact of urban expansion on habitat quality in Beijing, forecasting land cover changes and ecological effects by 2030. Using CA–Markov and FLUS models, the research analyzes habitat quality from 2000 to 2030 through the InVEST model, revealing a significant urban land increase of 1316.47 km2 and a consequent habitat quality decline. Predictions for 2030 indicate varying habitat quality outcomes across three scenarios: ecological priority (0.375), natural growth (0.373), and urban development (0.359). We observed that the natural growth scenario forecasts a further decline in habitat quality, primarily due to increased low–value habitat regions. Conversely, the ecological priority scenario projects a notable improvement in habitat quality. To mitigate habitat degradation in Beijing and enhance regional habitat quality and ecological conditions, it is recommended to control urban land cover expansion, adopt effective ecological conservation policies, and systematically carry out national spatial restructuring and ecological restoration. This research provides vital decision–making support for urban planning and ecological conservation, emphasizing the need for comprehensive land cover and ecological strategies in urban development. Additionally, our findings and methodologies are applicable to other rapidly urbanizing cities worldwide. This demonstrates the broader applicability and relevance of our research, providing a framework for sustainable urban planning in diverse global contexts.
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- 2024
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22. Experimental and kinetic study on di-tertiary butyl peroxide auto-ignition and its effect on the ignition of n-heptane
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Zhongjun Wan, Zujun Zheng, Ping Li, and Changhua Zhang
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Heptane ,Materials science ,020209 energy ,General Chemical Engineering ,Organic Chemistry ,Analytical chemistry ,Energy Engineering and Power Technology ,02 engineering and technology ,Combustion ,Kinetic energy ,Branching (polymer chemistry) ,Peroxide ,Dissociation (chemistry) ,law.invention ,Ignition system ,chemistry.chemical_compound ,Fuel Technology ,020401 chemical engineering ,chemistry ,law ,Excited state ,0202 electrical engineering, electronic engineering, information engineering ,0204 chemical engineering - Abstract
Di-tertiary butyl peroxide is commonly used as ignition improver. In this work, auto-ignition properties of di-tertiary butyl peroxide and its promoting effect on n-heptane ignition were investigated systematically using a shock-tube facility. Ignition delay times were determined by measuring the time interval between electronically excited CH* emission and reflected shock pressure signals monitored at shock-tube sidewall. An empirical correlation for ignition delay times of di-tertiary butyl peroxide as a function of temperature, pressure and equivalence ratio was deduced by linear regression analysis. The quantitative effect of di-tertiary butyl peroxide on n-heptane ignition was obtained. The addition of di-tertiary butyl peroxide can dramatically decrease the ignition delay time of n-heptane, especially at high pressures and low temperatures. A two-step dissociation mechanism of di-tertiary butyl peroxide was combined with an n-heptane combustion mechanism to model the ignition characteristics. Sensitivity and reaction pathway analyses were carried out to identify the dominant reactions and fuel consumption paths during the ignition process, and to analysis the effect of di-tertiary butyl peroxide addition. The chain branching reaction CH3 + HO2 = CH3O + OH plays a dominant role in ignition promotion.
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- 2020
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23. Addressing Public Speaking Anxiety in Multicultural Counselling: The Use of Cognitive-Behavioural Therapy for International Students
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Moh. Khoerul Anwar, Muhammad Izzul Haq, Diafi Salma, and Zhongjun Wang
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cognitive behavioral therapy ,multicultural counseling ,public speaking anxiety ,terapi perilaku kognitif ,konseling multikultural ,kecemasan berbicara di depan umum ,Special aspects of education ,LC8-6691 - Abstract
Abstract: Several studies have highlighted the importance of Cognitive Behavioural Therapy (CBT) in reducing public speaking anxiety. The studies also denote the increase of confidence by strengthening self-efficacy. This study explores previous studies that uncover the use of CBT in dealing with public anxiety to identify its potential as part of multicultural counseling for international students in higher education. International students have different academic and learning cultures, as well as social environments, affecting the development of certain anxiety in dealing with pressures to adapt to new environments. Therefore, it positions the investigation of CBT’s ability to reduce public speaking anxiety for international students as highly essential. This study contends that CBT is a useful technique to unpack irrational fear of speaking in public and promote self-efficacy, developing confidence and leading to good mental health. However, given the nature of targeted intervention are international students, multicultural counseling competencies are undoubtedly required for the therapy. Abstrak: Beberapa penelitian telah menyoroti pentingnya Terapi Perilaku Kognitif (CBT) dalam mengurangi kecemasan berbicara di depan umum. Studi ini menunjukkan adanya peningkatan kepercayaan diri dengan memperkuat efikasi diri. Studi ini juga mengeksplorasi studi sebelumnya yang mengungkap penggunaan CBT dalam menangani kecemasan publik untuk mengidentifikasi potensinya sebagai bagian dari konseling multikultural untuk mahasiswa internasional di pendidikan tinggi. Mahasiswa internasional memiliki budaya akademik, pembelajaran, dan lingkungan sosial yang berbeda, yang semuanya memengaruhi perkembangan kecemasan tertentu dalam menghadapi tekanan untuk beradaptasi dengan lingkungan baru. Oleh karena itu, penelitian tentang CBT untuk mengurangi kecemasan berbicara di depan umum bagi mahasiswa internasional sangat penting. Studi ini berpendapat bahwa CBT adalah teknik yang berguna untuk membongkar ketakutan irasional berbicara di depan umum dan mempromosikan efikasi diri, mengembangkan kepercayaan diri dan mengarahkan kesehatan mental yang baik. Namun, mengingat sifat intervensi yang ditargetkan adalah siswa internasional, kompetensi konseling multikultural tidak diragukan lagi diperlukan dalam terapi.
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- 2022
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24. Model-Free Adaptive Nonsingular Fast Integral Terminal Sliding Mode Control for Wastewater Treatment Plants
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Baochang Xu, Zhongjun Wang, Zhongyao Liu, Yiqi Chen, and Yaxin Wang
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wastewater treatment ,dissolved oxygen ,data-driven control ,model-free adaptive control ,dynamic linearization ,fast integral terminal sliding mode control ,Technology ,Engineering (General). Civil engineering (General) ,TA1-2040 ,Biology (General) ,QH301-705.5 ,Physics ,QC1-999 ,Chemistry ,QD1-999 - Abstract
The regulation of wastewater treatment plants (WWTPs) is a challenge due to their complex biological and chemical characteristics and their accurate mathematical model is generally not accessible because of the limitation of available measurements. To overcome such challenges, in this paper, a novel model-free adaptive nonsingular fast integral terminal sliding mode control (MFA-NFITSMC) is proposed. Firstly, based on the concept of dynamic linearization, a compact format dynamic linearized (CFDL) data model for the WWTP is established. Secondly, a novel fast integral terminal sliding mode surface is proposed to accelerate the convergence of tracking error and a discrete-time MFA-NFITSMC is created using the CFDL model as a basis; then, its stability is proved by theoretical analysis. Finally, the experimental verification is conducted based on the Benchmark Simulation Model No. 1 and the results show that the proposed method has a higher tracking accuracy and stronger robustness than other methods in the control of WWTPs.
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- 2023
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25. Seroprevalence of Toxoplasma gondii infection in women with a gynecological tumor living in eastern China
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Zhongjun Wang, Tingting Qu, Huiyang Qi, Shuchao Zhao, Hailei Shi, Wenye Bai, Yang Yu, Xiao Wu, and Peng Zhao
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Toxoplasma gondii ,Gynecological tumor ,Seroprevalence ,Medicine ,Biology (General) ,QH301-705.5 - Abstract
The association between Toxoplasma gondii (T. gondii) infection and malignancy has attracted increased attention in recent years, but little is known of T. gondii infection among women diagnosed with a gynecological tumor (GT) in China. We conducted a case-control study involving 460 women diagnosed with a GT and 460 age-matched healthy controls (HCs) to estimate the infection process of T. gondii and understand the risk factors of T. gondii infection in patients with a GT. Levels of anti-T. gondii IgG and IgM were measured by enzyme-linked immunoassays every 12 months. After a median follow-up time of 4.3 years (range 4 to 5 years), 55/460 (11.96%) patients with a GT and 15/460 (3.26%) HCs were seroprevalence for T. gondii antibodies, respectively (P = 0.001). IgG antibodies against T. gondii were found in 54 GT patients (11.74%) and 15 HCs (3.26%), respectively (P = 0.001). The seroprevalence of T. gondii IgM antibodies was similar in patients with a GT and with HCs (2.83% vs 1.3%, P = 0.105). Multivariate stepwise logistic regression analysis revealed contact with cats (OR, 6.67; 95% CI [2.89–10.75]; P = 0.001), exposure to soil (OR, 2.16; 95% CI [1.14–4.10]; P = 0.019), being a farm-worker (OR, 4.17; 95% CI [1.20–11.49]; P = 0.006) and history of chemotherapy (OR, 3.16; 95% CI [1.56–6.45]; P = 0.001) to be independent risk factors for T. gondii infection. Women with an ovarian cancer or endometrial cancer had higher T. gondii seroprevalence than that of HCs. Moreover, T. gondii infection in patients with a GT mostly acquired within two years of diagnosis, but the infection in healthy controls had no obvious time characteristics. Here, we demonstrated that T. gondii infection is significantly higher in patients with a GT (especially in women with an ovarian tumor) compared to HCs. Thus, infection with this parasite should be avoided in patients with a GT, and the causal relationship between T. gondii and GTs should be studied in detail.
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- 2022
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26. Comparative study of the physiological and psychological effects of forest and urban auditory stimulus on humans
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Jiaqi Li, Guangyu Wang, Zhongjun Wang, William Wang, Huijie Chen, and Mei He
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Wellness ,Physiological ,Psychological ,Auditory stimulus ,Forest therapy ,Environmental sciences ,GE1-350 ,Geography (General) ,G1-922 - Abstract
Demand for parks and green space for physical and mental relaxation has increased dramatically during and after the COVID−19 Pandemic in many countries. In order to understand nature and forest experience with human health, we conducted multi-disciplinary research to examine if different auditory stimuli will cause the change of healthy people's physiological and psychological effects, especially under typical forest therapy activity---focused-attention meditation (FAM). In this study, we recorded the data of heart rate, blood pressure as well as brainwave activities as physiological indices. We used a modified Semantic Differential Method (SD) to investigate participants' subjective feelings on different sound stimuli. A significant increase in heart rate was found during meditation under a street sound auditory background. The theta band power reduced significantly compared to that under other sound stimulation. The highest feeling scores on the level of comfort, relaxation, and nature showed with the presence of a natural sound environment. In conclusion, the natural sound background of the forest can make people more relax physically and psychologically during meditation.
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- 2021
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27. An inexact multi-stage interval-parameter partial information programming model for water resources management under uncertainties
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Hongguang Chen and Zhongjun Wang
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inexact multistage stochastic programming ,linear partial information theory ,uncertainties ,urban water resources management ,Water supply for domestic and industrial purposes ,TD201-500 ,River, lake, and water-supply engineering (General) ,TC401-506 - Abstract
The urban water shortage crisis around the world is increasing. In this study, an inexact multi-stage interval-parameter partial information programming model (IMIPM) is proposed for urban water resources planning and management under uncertainties. Optimization techniques of two-stage stochastic programming (TSP), interval-parameter programming (IPP), linear partial information theory (LPI) and multistage stochastic programming (MSP) are combined into one general framework. IMIPM is used to tackle uncertainties like interval numbers, water inflow probabilities expressed as linear partial information, dynamic features in a long planning time and joint probabilities in water resources management. It is applied to Harbin where the manager needs to allocate water from multi-water sources to multi-water users during multi-planning time periods. Four water flow probability scenarios are obtained, which are associated with uncertainties of urban rainfall information. The results show that the dynamics features and uncertainties of system parameters (such as water allocation targets and shortage) are considered in this model by generating a set of representative scenarios within a multistage context. The results also imply that IMIPM can truly reflect the actual urban water resources management situation, and provide managers with decision-making space and technical support to promote the sustainable development of economics and the ecological environment in cities. HIGHLIGHTS Combine techniques of interval-parameter method, multistage stochastic method, linear partial information theory, and two-stage stochastic programming into one framework.; Authors apply it in a real-world water resources problem.; An interactive algorithm is introduced to deal with this model.; The results can support managers in having multiple decision alternatives.; It can apply in water or other resource problems.;
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- 2021
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28. Study on as-cast microstructure of Fe-15Mn-10Al-5Ni-0.8C low density duplex steel
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Zhihe Guo, Fengya Hu, Zhongjun Wang, Kuijun Fu, Weijuan Li, and Jiaji Wang
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Fe-Mn-Al-C low density steels ,as-cast organization ,austenite ,δ- ferrite ,Materials of engineering and construction. Mechanics of materials ,TA401-492 ,Chemical technology ,TP1-1185 - Abstract
The microstructure of Fe-15Mn-10Al-5Ni-0.8C low density duplex steel ingots was studied by laser confocal scanning calorimetry , metallographic microscopy and scanning electron microscopy. The results indicated that: the microstructure of Fe-15Mn-10Al-5Ni-0.8C low density steel was mainly composed of coarse austenite dendrites and δ -ferrite phase in dendrite. The δ -ferrite could be completely eliminated by solution treatment. A dynamic model of austenite grain growth was established. Through analysis, it was concluded that the critical temperature for rapid austenite growth was 1250 °C. The activation energy for austenite grain growth was 365 KJ/mol as calculated by Sellars’ model.
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- 2022
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29. Seroprevalence and risk factors of Toxoplasma gondii infection in children with leukemia in Shandong Province, Eastern China: a case—control prospective study
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Na Zhou, Haiyang Fu, Zhongjun Wang, Hailei Shi, Yang Yu, Tingting Qu, Longlong Wang, Xiangyan Zhang, and Lin Wang
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Toxoplasma gondii ,Risk factors ,Leukemia children ,Seroprevalence ,Medicine ,Biology (General) ,QH301-705.5 - Abstract
Limited information is available concerning the epidemiology of Toxoplasma gondii infection in children with leukemia in Eastern China. Therefore, a case-control study was conducted to estimate the seroprevalence of toxoplasmosis in this patient group and to identify risk factors and possible routes of infection. Serum samples were collected from 339 children with leukemia and 339 age matched health control subjects in Qingdao from September 2014 to March 2018. Enzyme linked immunoassays were used to screen anti- T. gondii IgG and anti- T. gondii IgM antibodies. Forty-eight (14.2%) children with leukemia and 31 (9.1%) control subjects were positive for anti-T. gondii IgG antibodies (P
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- 2019
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30. Growth behavior and kinetics of austenite grain in low-carbon high-strength steel with copper
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Fanyun Meng, Jiaji Wang, Jing Guo, Kuijun Fu, Ming Zhao, Zhongjun Wang, and Zhen Xu
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low-carbon high-strength steel with copper ,austenite grain growth ,copper bearing precipitates ,solid solution ,Materials of engineering and construction. Mechanics of materials ,TA401-492 ,Chemical technology ,TP1-1185 - Abstract
A low-carbon high-strength steel with copper has better antibiological corrosion property, more widely used in large marine projects and ships. In this study, an austenite grain growth model of a low-carbon ship plate steel with 1.6Cu was established by using Sellars equation at 900 °C–1200 °C and different holding times (30–120 min) to reveal its kinetics. The pinning effect of grain boundary precipitates was studied by scanning electron microscopy (SEM) and transmission electron microscopy (TEM), and a quantitative relationship between the solid solution and precipitation behavior of copper bearing precipitates in experimental steel and austenite grain growth was analyzed. The experimental results show that the austenite grains grow slowly, and the grains are fine grains when the heating temperature is below 1000 °C and the transition temperature of rapid grain coarsening is 1000 °C. The relative error of dynamic model can be controlled within 8.5%. During heat treatment, Cu atoms are segregated at the grain boundary to form a copper-rich region, providing a coating effect on the carbide and grain boundary and hindering the growth of grains. With the increase in temperature, the diffusion rate of copper atoms increases, and the precipitates containing copper are rapidly dissolved into austenite. Therefore, the pinning effect is weakened, and the austenite grains grow rapidly.
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- 2021
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31. Moving toward a Greener China: Is China’s National Park Pilot Program a Solution?
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Gonghan Sheng, Heyuan Chen, Kalifi Ferretti-Gallon, John L. Innes, Zhongjun Wang, Yujun Zhang, and Guangyu Wang
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national park ,pilot program ,environmental sustainability ,governance ,economic development ,Agriculture - Abstract
National parks have been adopted for over a century to enhance the protection of valued natural landscapes in countries worldwide. For decades, China has emphasized the importance of economic growth over ecological health to the detriment of its protected areas. After decades of environmental degradation, dramatic loss of biodiversity, and increasing pressure from the public to improve and protect natural landscapes, China’s central government recently proposed the establishment of a pilot national park system to address these issues. This study provides an overview of the development of selected conventional protected areas (CPAs) and the ten newly established pilot national parks (PNPs). A literature review was conducted to synthesize the significant findings from previous studies, and group workshops were conducted to integrate expert knowledge. A qualitative analysis was performed to evaluate the effectiveness of the pilot national park system. The results of this study reveal that the PNP system could be a potential solution to the two outstanding issues facing CPAs, namely the economic prioritization over social and ecological considerations that causes massive ecological degradation, and the conflicting, overlapping, and inconsistent administrative and institutional structures that result in serious inefficiencies and conflicts.
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- 2020
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32. Precipitation behavior of yttrium-rich nano-phases in AlCoCrFeNi2.1Yx high-entropy alloy
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Minghong Sha, Yanwen Zhou, Ning Wang, Dechuan Yu, Zhongjun Wang, Xingang Ai, Hongbin Wang, Minggang Shen, and Shengli Li
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yttrium ,double yielding ,microstructure ,nano-precipitate ,high-entropy alloy ,Materials of engineering and construction. Mechanics of materials ,TA401-492 ,Chemical technology ,TP1-1185 - Abstract
In this paper, rare earth element yttrium (Y) was selected to be doped into AlCoCrFeNi _2.1 Y _x _ ( _x _ = 0, 0.1%, 0.3%, 0.5%, and 1.0%) high-entropy alloy in order to refine grain and increase yielding strength. The precipitation behavior of the Y-rich nano-phases in the face centered cubic (FCC (L1 _2 )) phase and the body centered cubic (BCC (B2)) phase was investigated by x-ray diffraction, scanning electron microscopy, high-resolution transmission electron microscopy and differential scanning calorimetry. Refined crystal grains were observed due to the high-density precipitation. The nano-phase within the BCC(B2) phase was (Al-Ni-Y)-rich phase and single cubic (SC) structure. The nano-phase formed within the FCC (L1 _2 ) phase was (Fe-Co-Cr-Y)-rich phase and FCC structure. Fine (Al-Ni-Y)-rich nano-particles were formed due to the addition of Y and the amount of the nano-phase increased with increasing Y content. The adoption of Y promoted dispersed precipitation of (Al-Ni-Y)-rich nano-phase under deformation. The more Y content, the more nano-precipitates. When Y =1.0 at.%, the lamellar structure was transformed into bamboo-like structure in the BCC phase due to the segregation of Y. Double yielding phenomenon occurred during the compression deformation of the AlCoCrFeNi _2.1 Y _x alloys (when x ≥ 0.5 at.%) and caused an increase of yielding strength by 40%. It was since the barrier effect of both the (Al-Ni-Y)-rich nano-precipitation and the (Fe-Co-Cr-Y)-rich nano-phases on the dislocations within grains and grain boundaries led to the second yielding. With the further increase of Y content, the lamellar BCC phase was separated from the bamboo-like BCC phase owing to the super-saturated precipitation and segregation of Y at the solidification front of B2 phase, leading to a degradation of mechanical properties.
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- 2020
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33. Evaluation analysis of scavenging process of two-stroke marine diesel engine by experiment and simulation
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Haiqiang LIU, Lin LU, and Zhongjun WANG
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two-stroke marine diesel engine ,scavenging process ,exhaust valve opening and closing ,fuel consumption ,nox emissions ,Mechanical engineering and machinery ,TJ1-1570 ,Mechanics of engineering. Applied mechanics ,TA349-359 - Abstract
The performance of the two-stroke engine depends on the scavenging process, which affects air-fuel mixture and combustion. This paper presents results from experiments in which the timing of exhaust valve opening and closing was varied in two-stroke marine diesel engine during shop testing, and reveals the effect on performance and emission, as well as the corresponding concept analysis. A simulation model was then developed based on AVL BOOST and experimental results, its validity was confirmed by actual measurements. This simulation enables a more thorough investigation into engine performance features and the scavenging process. In particular it provides a detailed examination of how changes in EVO and EVC timing impact the scavenging process and ultimately engine performance. These results are summarized, and based on these results, optimal EVO and EVC settings are suggested for balancing the scavenging process, and also the engine performance and NOx emissions.
- Published
- 2014
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