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DEVELOPMENT OF COMPUTER SIMULATION SOFTWAREON PHASE TRANSFORMATION DURING QUENCHING

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Acta Metallurgica Sinica(English Letters) 2000年第2期13卷 618-622页

作者： L. chen, W. x.a and x. j. chen Department of Materials Science and Engineering, Nanchang Institute of Aeronautical Technology, Nanchang 330034, China

A computer software to simulate the phase transformation during quenching is designed based on Avrami equation and Scheil additivity principle of incubation period. The isothermal transformation diagrams of supercooled austenite are described by cubic spline functions. This software is possess of a good graphic interface of Windows style, can simulate the whole process in austenite decomposition during continuous cooling. If the cooling rate was given, the fraction of various microstructures transformed of austenite decomposition during continuous cooling at any temperature can be calculated. The simulation results are checked with the quenching ex.eriment of 45 steel. The results indicate that the simulation results are comparatively close to the ex.erimental results.

关键词： quenching phase transformation computer simulation software

Decolorization of Direct Black 22 by Aspergillus ficuum

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j.urnal of Environmental Sciences 2001年第4期13卷 472-475页

作者： Dong, x.-j. Du, Z.-y. chen, Z. Dept. of Biology/Environmental Sci. Wenzhou Normal College Wenzhou 325003 China

The decolorization of Direct Black 22 by Aspergillus ficuum has been studied. It was found that Aspergillus ficuum could effectively decolorize Direct Black 22 especially when grown as pelleted mycelia. Results showed that the media containing Direct Black 22 at 50 mg/L could be decolorized by 98.05% of the initial color in 24 h. The optimum pH and temperature of decolorization are 4.0 and 33 °C respectively. Aeration was quite beneficial to decolorization. Medium composition and the concentration of Direct Black 22 could affect the rate of decolorization. The dye degraded products assayed by UV-visible spectrophotometer and macroscopic observation showed that the decolorization of Direct Black 22 by mycelial pellets includes two important processes: bioadsorption and biodegradation. The degradation ex.eriment agree with the Michaelis-Menten kinetics equation.

关键词： Bioassay Biodegradation Color Concentration (process) Dyes pH Ultraviolet spectrophotometers

Improvement of elevated-temperature strength and recrystallization resistance via Mn-containing dispersoid strengthening in Al-Mg-Si 6082 alloys

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j.urnal of Materials Science & Technology 2020年第4期39卷 135-143页

作者： chen Li Kun Liu x.-Grant chen Department of Applied Science University of Québec at ChicoutimiChicoutimiQC G7H 2B1Canada

The precipitation behavior of Mn-containing dispersoids in Al-Mg-Si 6082 alloys with different Mn contents(0,0.5 and 1.0 wt%)during various heat treatments(300–500℃)was *** effects of dispersoids on elevated-temperature strength and recrystallization resistance during hot-rolling and post-rolling annealing were *** results showed that the dispersoids in the Mn-containing alloys(0.5 and 1.0%)began to precipitate at 350℃and reached the optimum conditions after 2–4 h at 400℃.However,the dispersoids coarsened with increasing holding time at temperatures above450℃.After the peak precipitation treatment at 400℃for 2 h,the yield strength at 300℃increased from 28 MPa(base alloy free of Mn)to 55 MPa(alloy with 0.5%Mn)and 70 MPa(alloy with 1%Mn),respectively,demonstrating a significant dispersoid strengthening effect at elevated *** addition,the dispersoids were thermally stable at 300℃for up to 1000 h holding owing to its relative high precipitation temperature(350–400℃),leading to the superior constant mechanical performance at elevated temperature during the long service *** hot rolling and post-rolling annealing,the presence of a large amount of dispersoids results in the higher Zener drag PZcompared with base alloy and then significantly improved the recrystallization *** alloy containing 0.5%Mn ex.ibited the highest recrystallization resistance among three ex.erimental alloys studied during the post-rolling process,likely resulted from the lower coarsening rate of dispersoids and the lower dispersoids free zone.

关键词： Al-Mg-Si 6082 alloy Mn addition Dispersoid precipitation Elevated-temperature strength Recrystallization resistance

ANALYSIS OF THREE-DIMENSIONAL UPSETTING PROCESS BY THE RIGID-PLASTIC REPRODUCING KERNEL PARTICLE METHOD

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Acta Metallurgica Sinica(English Letters) 2006年第5期19卷 371-378页

作者： Y. H. Liu j. chen S. Yu x. W. chen National Die and Mould CAD Engineering Research Center Shanghai Jiao Tong UniversityShanghai 200030 China

A meshless approach, called the rigid-plastic reproducing kernel particle method （RKPM）, is presented for three-dimensional （3D） bulk metal forming simulation. The approach is a combination of RKPM with the flow theory of 3D rigid-plastic mechanics. For the treatments of essential boundary conditions and incompressibility constraint, the boundary singular kernel method and the modified penalty method are utilized, respectively. The arc-tangential friction model is employed to treat the contact conditions. The compression of rectangular blocks, a typical 3D upsetting operation, is analyzed for different friction conditions and the numerical results are compared with those obtained using commercial rigid-plastic FEM （finite element method） software Deform^3D. As results show, when handling 3D plastic deformations, the proposed approach eliminates the need of ex.ensive meshing and remeshing procedures which are unavoidable in conventional FEM and can provide results that are in good agreement with finite element predictions.

关键词： meshless reproducing kernel particle method(RKPM) three-dimensional upsetting incompressibility modified penalty method

Effects of Mn content on recrystallization resistance of AA6082 aluminum alloys during post-deformation annealing

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j.urnal of Materials Science & Technology 2020年第17期52卷 189-197页

作者： x.aoming Qian Nick Parson x.-Grant chen Department of Applied Science University of Quebec at ChicoutimiSaguenay G7H 2B1Canada Arvida Research and Development Centre Rio Tinto AluminumSaguenay G7S 4K8Canada

The microstructural evolutions under as-homogenized and as-deformed conditions and after the postdeformation annealing of AA6082 aluminum alloys with different Mn content(0.05 wt.%-1 wt.%)were studied by optical,scanning electron,and transmission electron *** results showed that the presence of a large amount ofα-Al(Mn,Fe)Si dispersoids induced by Mn addition significantly improved the recrystallization *** the base alloy free of Mn,static recrystallization occurred after 2 h of annealing,and grain growth commenced after 4 h of annealing,whereas in Mn-containing alloys,the recovered grain structure was well-retained after even 8 h of *** alloy with 0.5%Mn ex.ibited the best recrystallization resistance,and a further increase of the Mn levels to 1%resulted in a gradual reduction of the recrystallization resistance,the reason for which was that recrystallization occurred only in the dispersoid-free zones(DFZs)and the increased DFZ fraction with Mn content led to an increase in the recrystallization *** variation in the dispersoid number density and a coarsening of dispersoids during annealing have a limited influence on the static recrystallization in Mn-containing alloys.

关键词： AA6082 alloys Mn effects Recrystallization resistance Dispersoid precipitation Post-deformation annealing

IGF-1R as an anti-cancer target—trials and tribulations

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Chinese j.urnal of Cancer 2013年第5期32卷 242-252页

作者： Helen x. chen Elad Sharon Cancer Therapy Evaluation Program National Cancer Institute

Type I insulin-like growth factor receptor (IGF-1R) has long been recognized for its role in tumorigenesis and growth, but only recently have the tools for targeting the IGF pathway become available. More than 10 IGF/IGF-1R inhibitors have entered clinical trials, and these belong to three main classes: (1) monoclonal antibodies against IGF-1R, (2) monoclonal antibodies against IGF-1R ligands (IGF-1 and IGF- 2), and (3) IGF-1R tyrosine kinase inhibitors. These IGF-1R-targeting agents share common effects on IGF-1R signaling but differ in mechanisms of action, spectrum of target inhibition, and pharmacological features. Clinical activity of IGF-1R inhibitors has been demonstrated with sustained responses in a small number of patients with select tumor types, such as Ewing sarcoma and thymoma. However, many large clinical trials involving patients with adult tumors, including non-small cell lung cancer, breast cancer, and pancreatic cancer, failed to show clinical benefit in the overall patient population. Possible reasons for failure include the complex.ty of the IGF-1R/insulin receptor system and parallel growth and survival pathways, as well as a lack of patient selection markers. While IGF-1R remains a valid target for selected tumor types, identification of predictive markers and rational combinations will be critical to success in future development.

关键词： IGF-1 酪氨酸激酶抑制剂胰岛素样生长因子生长因子受体单克隆抗体肿瘤发生临床试验抗癌

Crustal magma ox.dation state and endowments in porphyry copper deposits

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Science China Earth Sciences 2025年第1期68卷 226-236页

作者： Yumin AI Massimo CHIARADIA Chao WU Huayong chen Key Laboratory of Mineralogy and Metallogeny Guangzhou Institute of Geochemistry Chinese Academy of Sciences University of Chinese Academy of Sciences Department of Earth Sciences University of Geneva Guangdong Provincial Key Laboratory of Mineral Physics and Materials

Porphyry copper deposits（PCDs） supply the maj.rity of the world's copper（Cu） as well as significant amounts of molybdenum（Mo） and gold（Au）. The formation of these deposits is controlled by a variety of geological factors, among which the magmatic ox.dation is one of the focuses of current research. This study investigates the redox.characteristics of arc magmas by analyzing the ratio of vanadium（V） to scandium（Sc） and its correlation with the ox.gen fugacity （fO2） of magmas from arcs of various crustal thicknesses globally. We compiled an ex.ensive dataset of published V/Sc values and studied the partition coefficients of Vand Sc between minerals and silicate melts across various magmatic environments. The results demonstrate that fractional crystallization of magnetite markedly reduces V/Sc values of the residual melt. Furthermore, magnesium number（Mg#） at the onset of magnetite fractionation is strongly positively correlated with fO2of the equilibrium magma. Based on this,the ox.dation of arc magmas from different crustal thicknesses can be evaluated. The result suggests that magmas generated in crusts thicker than 20 km tend to be more ox.dized with increasing crust thickness. This trend is attributed to enhanced intracrustal differentiation processes involving garnet and amphibole, particularly in mature island and continental arcs. In contrast,magmas in thinner arc crusts（x.dation states than most of their thicker crust counterparts. These findings suggest that both subduction dynamics and crustal thickness play a vital role in determining the ox.dation state of arc magmas and, consequently, their capacity to generate PCDs. Highly ox.dized, primitive arc magmas are less favorable for PCD formation due to that they tend to ex.erience magnetite fractionation and thus sulfide saturation in the early stage of magma evolution, a process leading to copper depletion. On the contra

关键词： Magma evolution V/Sc systematics Magnetite Ox.gen fugacity Porphyry copper deposits

Late Paleozoic–Early Mesozoic tectonic evolution of the Zongwulong Shan-Qinghai Nanshan tectonic belt in the northern Qaidam continent， northern Tibet

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j.urnal of Earth Science 2025年

作者： Yonghui Zhao chen Wu j.e Li Peter j.Haproff Lin Ding State Key Laboratory of Tibetan Plateau Earth System and Resources Environment (TPESRE)， Institute of Tibetan Plateau Research， Chinese Academy of Sciences University of Chinese Academy of Sciences Chongqing Key Laboratory of Complex.Oil and Gas Field Ex.loration and Development， Chongqing University of Science and Technology Department of Earth and Ocean Sciences， University of North Carolina Wilmington

The Zongwulong Shan-Qinghai Nanshan tectonic belt of the northern Tibet Plateau ex.erienced a protracted tectonic history， including the openings and closures of the Proto- and Paleo-Tethyan Oceans. Although the tectonic belt has been ex.ensively studied， details regarding the tectonic processes involved in its development remain controversial. To better constrain the tectonic processes of this tectonic belt， we conducted detailed field geological mapping， zircon U-Pb geochronology， and whole-rock geochemical and Sr-Nd isotopic analyses. Our results show that intrusive rocks in the tectonic belt crystallized in ca. 292–233 Ma， perhaps in an arc/subduction setting. Geochemical and Sr-Nd isotopic data suggest that early Permian–late Triassic ultramafic-intermediate intrusions were sourced from the enriched mantle， whereas intermediate-acidic rocks were sourced from mix.d crust-mantle. We present the tectonic model that involves: (1) Early Devonian–early Permian intracontinental ex.ension occurred in the northern margin of the Qaidam continent (ca. 416 Ma–292 Ma); (2) Early Permian–late Triassic northward subduction of the Paleo-Tethyan Ocean resulted in arc magmatism (ca. 292 Ma–233 Ma); and (3) subsequent late Triassic intracontinental ex.ension (ca. 233 Ma–215 Ma). Our results suggest that the late Paleozoic–early Mesozoic development of the Zongwulong Shan-Qinghai Nanshan was related to the opening， subduction， and slab retreat of the Paleo-Tethyan Ocean， which has key implications for the tectonic evolution of the northern Tibetan Plateau.

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Utility of semivariogram for spatial variation of soil nutrients and the robust analysis of semivariogram

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j.urnal of Environmental Sciences 2001年第4期13卷 453-458页

作者： Guo, x.-d. Fu, B.-j. Ma, K.-m. chen, L.-d. Department of Systems Ecology Res. Cntr. Eco-Environmental Sci. Chinese Academy of Sciences Beijing 100085 China

The spatial variation of soil nutrients in topsoil (0-20cm) was analyzed using semivariogram in the Zunhua County of Hebei Province, China. The effect on semivariogram with randomly deleted data and kriged estimates using various reduced sample sizes was also analyzed. The semivariograms of available N, total N, available P, organic matter were best described by a spherical model, ex.ept for available K, which best fitted a complex.structure of ex.onential model and linear with sill model. The ratio of nugget to total sample variance ranged from 34.4% to 68.4%, indicating the spatial correlation of tested soil nutrients on a large scale was moderately dependent. Among five soil nutrients, available nitrogen and available phosphorus had the shortest spatial correlation range (5 km and 5.5 km), available K had the longest range (25.5 km), whereas total nitrogen and organic matter had intermediate spatial correlation range (14.5 km and 8.5 km). The semivariograms of available N, total N, available P, and organic matter were insensitive to a 50%-60% reduction in original sampling density, while for available K, it is up to 70%. The estimated spatial distributions of total N by kriging, under various reduced sample sizes, all correlated significantly (P = 0.001) with those obtained from original data. The results showed that the semivariogram was a relatively robust tool when used in a large region and sufficient spatial variation information could be relained regardless of a higher deletion proportion of the original data. The original sample data could be reduced by kriging and the estimates showed no loss of spatial information, however, the results may be unreliable unless a clearly identified semivariogram model could be obtained. The results may provide useful information for determining the appropriate sampling densities for these scales of soil survey.

关键词： Correlation methods Data reduction Nitrogen Phosphorus Sampling Soils Surveying