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Formation mechanism of spheroidal carbide in ultra-low carbon ductile cast iron

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China Foundry 2016年第5期13卷 346-351页

作者： Bin-guo Fu Zhuo-qing Li Xue-bo Zhao Zhen Shen guo-lu Li Jin-hai Liu School of Materials Science and Engineering Hebei University of Technology

The formation mechanism of the spheroidal carbide in the ultra-low carbon ductile cast iron fabricated by the metal mold casting technique was systematically investigated. The results demonstrated that the spheroidal carbide belonged to eutectic carbide and crystallized in the isolated eutectic liquid phase area. The formation process of the spheroidal carbide was related to the contact and the intersection between the primary dendrite and the secondary dendrite of austenite. The oxides of magnesium, rare earths and other elements can act as heterogeneous nucleation sites for the spheroidal carbide. It was also found that the amount of the spheroidal carbide would increase with an increase in carbon content. The cooling rate has an important influence on the spheroidal carbide under the same chemical composition condition.

关键词： ultra-low carbon ductile cast iron cooling rate nucleation core spheroidal carbides formation mechanism

Simulation on stress of large diameter CADI grinding ball based on ANSYS

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China Foundry 2020年第3期17卷 227-234页

作者： Xue-bo Zhao Jian-shuai Yan Jin-hai Liu Bin-guo Fu Wei-ting Yang guo-lu Li School of Materials Science and Engineering Hebei University of TechnologyTianjin 300130China

The falling ball tests were carried out on theΦ125 mm diameter Carbidic Austempered Ductile Iron(CADI)grinding balls with Mn content of 2.0wt.%,2.3wt.%,2.6wt.%and 3.0wt.%,respectively,and the kind of grinding ball with the most serious spalling was selected for stress *** stress distribution between four grinding balls in the elbow of the falling ball test device when they collided with each other was simulated based on *** of the falling ball tests show that the spalling and mass loss of a CADI grinding ball increases with the increase of Mn content,and the CADI grinding ball with 3.0wt.%Mn shows the most obvious spalling and mass *** simulation results of stress distribution of a CADI grinding ball show that the maximum impact stress does not appear in the center of the contact area,but in the annular area(inner diameter of^20 mm and outer diameter of^50 mm)in the section with a depth of 5-15 mm below the grinding ball *** actual spalling of the ball is consistent with the simulation results,and the oxide-based impurities in CADI grinding ball accelerate the spalling of the grinding ball in service.

关键词： CADI stress grinding ball ANSYS

Role of bonding filling on HER/OER/ORR multifunctional catalytic activity in transition-metals-doped PdPX(X=S,Se,Te)

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Rare Metals 2024年第10期43卷 5126-5140页

作者： Hai-Hua Huang Wei Li Cheng-Chao Hu Xue-Qin Sun Lin-guo lu Xiao-Feng Fan School of Materials Science and Engineering Laboratory of Sensitive Materials and DevicesShandong Department of EducationLiaocheng UniversityLiaocheng 252059China School of Environmental and Material Engineering Yantai UniversityYantai 264005China Department of Physics University of Puerto RicoRio PiedrasSan Juan.PR00931USA Key Laboratory of Automobile Materials(Jilin University) Ministry of EducationCollege of Materials Science and EngineeringJilin UniversityChangchun 130012China

The development of stable and highly efficien multifunctional electrocatalysts for the hydrogen evolution reaction(HER),oxygen reduction reaction(ORR)and oxygen evolution reaction(OER)are essential for the efficient conversion and storage of renewable *** significant advantages of single-atom catalysts,such as strong metal slab interactions,unsaturated coordination and efficient atomic utilization,have opened new avenues for designing multifunctional ***,based on density functional theory,a single atom doped PdPX system was designed as a multifunctional electrocatalyst,which demonstrated the synergistic effect between defects and transition metal atoms and led to enhanced catalytic *** results showed that PdPS/PdPSe with P/X vacancy,PdPTe with P/Pd vacancy and Co/Rh/Ir@PdPX exhibited promising HER ***@PdPS(Se),with an overpotential of 0.56(0.44)V,was predicted to be a promising OER ***,Rh(Ir)@PdPS(Se)catalysts exhibited efficient catalytic properties for ORR Besides,Co@PdPS(Se),Rh(Ir)@PdPS~(V(S)),Co@PdP-Se~(V(Se))and Ir@PdPS~(V(S)-1)exihibited multifunctional catalytic performance with moderate ***,the origin of catalytic activity was revealed by using the crystal orbital Hamilton populations *** a strong adsorption system,proper filling of the anti-bonding state can increase the energy of the system,weaken the adsorption strength,and facilitate the desorption of intermediates Conversely,augmenting bonding states can enhance its adsorption *** findings provide theoretica guidance for the design and fabrication of novel multifunctional electrocatalysts in terms of filling of bondingstate.

关键词： Electrocatalyst Two-dimensional PdPX Water splitting Density functional theory

Fabrication of intra porous PVDF fibers and their applications for heavy metal removal,oil absorption and piezoelectric sensors

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Journal of Materiomics 2023年第1期9卷 174-182页

作者： Gajula Prasad Xiongwei Lin Junwei Liang Yingbang Yao Tao Tao Bo Liang Sheng-guo lu Guangdong Provincial Research Center on Smart Materials and Energy Conversion Devices Guangdong Provincial Key Laboratory on the Functional Soft Condensed MatterSchool of Materials and EnergyGuangdong University of TechnologyGuangzhou510006China Dongguan South China Design Innovation Institute Building D-1University Innovation City AreaSongshan LakeDongguan523808China

Intra porous fibrous membranes have enhanced metal ionic adsorption and oil separation abilities than those of intra nonporous fibrous *** this paper,we prepared highly intra porous fibrous poly(vinylidene fluoride)(PVDF)membranes using an innovated water-mediated electrospinning ***-ATR and XRD techniques confirmed the conversion of non-polarα-phase to polarβ-phase in electrospun *** porous fibrous membrane M–16 had adsorbed oil almost 120%and metal adsorption around 15%,12%,5%,13%respectively for Pb^(2+),Cd^(2+),Cu^(2+)and Zn^(2+),which are larger than the counterpart of nonporous M–*** nonporous fibrous membranes have better peak to peak output voltage(Vp-Vp)2 to 3 times than the porous fibrous membranes(M–16).The results show apparent potential applications in wastewater/oil spill treatment as well as piezoelectric sensors.

关键词： poly(vinylidene fluoride) Porous fibrous membrane Metal removal Oil absorption and peak to peak output voltage

Fuzzy Synthetic Evaluation of Wetland Soil Quality Degradation:A Case Study on the Sanjiang Plain,Northeast China

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Pedosphere 2009年第6期19卷 756-764页

作者： WANG Jian-Hua lu Xian-guo JIANG Ming LI Xiao-Yan TIAN Jing-Han State Key Laboratory of Earth Surface Processes and Resource Ecology Beijing Normal University Beijing 100875 (China) Northeast Institute of Geography and Agricultural Ecology Chinese Academy of Sciences Changchun 130012 (China) Hebei Cangzhou Teachers College Cangzhou 061001 (China) College of Resources Science and Technology Beijing NoT-real University Beijing 100875 (China)

Wetland soil quality degradation caused by large-scale agricultural reclamation on the Sanjiang Plain of Northeast China has been widely reported. A relative soil quality evaluation (RSQE) model and a projection pursuit evaluation (PPE) model based on real-coded accelerating genetic algorithm were introduced to evaluate quality variations in top layers of the main wetland soils on the Sanjiang Plain in 1999 and 2003, respectively. As soil quality degradation boundaries were vague, this study established two fuzzy synthetic evaluation (FSE) models based on the original data and criteria used in the RSQE and PPE models. The outputs of the two FSE models were obtained by choosing two fuzzy composite operators M(∧, ∨) and M(·, ⊕). Statistical analysis showed that the results of the FSE, RSQE, and PPE models were correlated. In particular, outputs of the FSE model using M(·, ⊕) were significantly correlated with those of the RSQE model with r = 0.989 at P luating soil quality degradation. However, the choice of composite operator was of critical importance. The study of wetland soil quality degradation on the Sanjiang Plain was of scientific and practical significance for protection and management of soils and for sustainable development of agriculture in this area in the future.

关键词： fuzzy composite operator model soil protection and management sustainable development of agriculture

Scaling of ac susceptibility and the nonlinear response function of high-temperature superconductors

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Science China(Physics,Mechanics & Astronomy) 2005年第1期48卷 14-25页

作者： CHEN Kaixuan NING Zhenhua XU Hengyi QI Zhi lu guo WANG Furen YIN Daole Department of Physics Peking University Beijing 100871 China Department of Physics Peking University Beijing 100871 China Department of Physics Peking University Beijing 100871 China Department of Physics Peking University Beijing 100871 China Department of Physics Peking University Beijing 100871 China Department of Physics Peking University Beijing 100871 China Department of Physics Peking University Beijing 100871 China

The amplitude-dependent ac susceptibility of high-temperature superconductors is shown to obey some empirical scaling relations. We try to analyze this behavior by extending a dc nonlinear response function of mixed state to the ac cases. The derived equations for critical current and ac susceptibility x(T) agree with the scaling relations of experimental data.

关键词： high-temperature superconductor, ac susceptibility, scaling law, nonlinear response.

Overexpression of AmDUF1517 enhanced tolerance to salinity, drought, and cold stress in transgenic cotton

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Journal of Integrative Agriculture 2018年第10期17卷 2204-2214页

作者： HAO Yu-qiong lu guo-qing WANG Li-hua WANG Chun-ling guo Hui-ming LI Yi-fei CHENG Hong-mei Biotechnology Research Institute Chinese Academy of Agricultural Sciences

As abiotic stresses become more severe as a result of global climate changes, the growth and development of plants are restricted. In the development of agricultural crops with greater stress tolerance, AmDUF1517 had been isolated from the highly stress-tolerant shrub Ammopiptanthus mongolicus, and can significantly enhance stress tolerance when inserted in Arabidopsis thaliana. In this study, we inserted this gene into cotton to analyze its potential for conferring stress tolerance. Two independent transgenic cotton lines were used. Southern blot analyses indicated that AmDUF1517 was integrated into the cotton genome. Physiological analysis demonstrated that AmD UF1517-transgenic cotton had stronger resistance than the control when treated with salt, drought, and cold stresses. Further analysis showed that trans-AmD UF1517 cotton displayed significantly higher antioxidant enzyme（superoxide dismutase（SOD）, peroxidase（POD）, catalase（CAT）, and glutathione S-transferase（GST）） activity and less reactive oxygen species（ROS） accumulation, which suggests that overexpression of AmDUF1517 can improve cotton resistance to stress by maintaining ROS homeostasis, as well as by alleviating cell membrane injury. These results imply that AmDUF1517 is a candidate gene in improving cotton resistance to abiotic stress.

关键词： transgenic cotton stress tolerance AmDUF1517 Ammopiptanthus mongolicus reactive oxygen species

STUDY ON THE SUSTAINABLE DEVELOPMENT OF WETLAND RESOURCES IN THE USSURI /WUSULI RIVER BASIN

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Chinese Geographical Science 2000年第3期10卷 79-84页

作者： Hong-yu Liu Xian-guo lu Chang-ke Wang Changchun Institute of Geography the Chinese Academy of Science 130021 Changchun P. R. China

The Ussuri/Wusuli River basin joins the border between the Northeast region of Heilongjiang Province of China and the Far East region of Russia. The watershed consists of approximately 26 000 000 ha and the shared border stretches more than 1100 km. The Ussuri River forms part of the border between Russia and China. Two thirds of the watershed ecosystem is in Russia, one third in China. Khanka / Xingkai Lake is the border Lake of Russia and China, with the area of 4380 km2. The Ussuri / Wusuli River Basin is rich in wetland resources, including surface water resources and wetlands. There are about more than 100 rivers belonging to one and two branch rivers, wetlands are mainly distributed in the Sanjiang Plain in China, which is the largest marsh area in China, with an area of 114 million ha. Human activities and agriculture reclamation for many years have led to many environment problems: 1)decreasing of wetland area led to loss of wetland environment functions, decreasing of biodiversity and increasing the number of natural disasters such as disastrous drought and waterlogging, which affect directly sustainable utilization of resources and economical development. 2) water supply is not evenly distributed, water pollution in rivers, marshes and lakes are more serious than before. Based on above study, some suggests of sustainable development in the basin have been made, which include: 1) developing the international wetland natural reserve and domestic comprehensive protected area to prevent wetlands from destruction and disturbance by human activities, 2) strengthening the protection and management of wetlands in lake shorelines and riparian zones (rivers and streams) to prevent water quality of rivers and lakes from pollution, 3) restoring the destroyed marsh in riparian zones and the  island like forests" of wetlands 4) developing positively transnational ecological tourist trade to promote the economic development in the river basin scope, 5) developing intern

关键词： wetland resources sustainable development the Ussuri River water resources

Significance of alpha-fetoprotein mRNA level in hepatocellular carcinoma patients treated with radiofrequency ablation

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Hepatobiliary & Pancreatic Diseases International 2007年第2期6卷 172-175页

作者： Du, Xi-Lin Ma, Qing-Jiu Wu, Tao Bao, guo-Qiang lu, Jian-guo Chu, Yan-Kui Fourth Mil Med Univ Dept Gen Surg Tangdu Hosp Xian 710038 Peoples R China

BACKGROUND: Many methods are used to treat liver cancer. Among them, radiofrequency ablation (RFA) is a hot topic because of its advantages. This study was designed to determine the significance of blood alpha-fetoprotein mRNA (AFPmRNA) changes in patients with hepatocellular carcinoma (HCC) treated with RFA. METHODS: The AFPmRNA content in blood samples from HCC patients was determined by reverse transcriptase-polymerase chain reaction (RT-PCR) before RFA and 48 hours, 72 hours, I week and 2 weeks later. RESULTS: The blood of 183 patients was negative for AFPmRNA before REA, but that of 62 of them was positive 72 hours later, then returned to negative after 2 weeks. The blood of 129 patients was positive for AFPmRNA before RFA, but that of 112 of them became negative 2 weeks later; 17 patients were still AFPmRNA positive 2 weeks after REA. CONCluSIONS: Blood AFPmRNA, which is increased temporarily after RFA, can be used as an objective index for the persistence and recurrence of HCC after REA.

关键词： aFPmRNA radiofrequency ablation carcinoma, hepatocellular RT-PCR