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An innovative process of clad teeming for preparing slab ingot

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Journal of Iron and Steel Research International 2022年第12期29卷 2006-2015页

作者： wen-bin Ma Yao-hui Jin Yu-an Jing wen-bin li Wei-da Yu Guang-long li Wan-ming li School of Materials and Metallurgy University of Science and Technology LiaoningAnshan 114051LiaoningChina Iron and Steel Research Institutes of Ansteel Group Corporation Anshan 114001LiaoningChina

An innovative process of clad teeming was proposed to prepare slab ingot,which featured a built-in cold core to inhibit solidification defects.A 20-kg clad ingot was prepared in the experiment,using a volume ratio of solid core to molten steel of 1:13 and a preheating temperature of cold core of 573 *** microstructures of the clad ingot were analyzed by comparing with a reference ingot without cold *** morphologies and mechanical properties of the clad ingot were studied before and after hot *** effect of cold core on heat transfer and nucleation during the solidification in clad ingot was *** show that the solidification microstructures in the clad ingot are refined and homogenized *** grain size in the center of the reference ingot is 2–3 times greater than that of clad ingot,and there is almost no columnar grain in the clad *** interfacial shear strength reaches 318 MPa,which shows excellent metallurgical bonding at the interface of cold core and molten *** defects at the interface are eliminated,and interfacial shear strength reaches 426 MPa after hot rolling with a 68.4%total reduction *** experiment and analysis of this process are expected to provide a new idea to prepare large ingots with refinement and homogeneity at a low cost.

关键词： Clad teeming Steel ingot Grain refinement Interface Cold core Interfacial mechanical property

Numerical simulation of the blast wave of a multilayer composite charge

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Defence Technology（防务技术） 2020年第1期16卷 96-106页

作者： Xiao-wen Hong Wei-bing li Wei Cheng wen-bin li He-yang Xu ZNDY of Ministerial Key Laboratory Nanjing University of Science and TechnologyNanjingPR China Chongqing Hongyu Precision Industrial Co. LtdChongqingPR China

The numerical simulation of a blast wave of a multilayer composite charge is investigated.A calculation model of the near-field explosion and far-field propagation of the shock wave of a composite charge is established using the AUTODYN finite element *** of the near-field and far-field calculations of the shock wave respectively converge at cell sizes of 0.25-0.5 cm and 1-3 *** Euler--fluxcorrected transport solver is found to be suitable for the far-field calculation after mapping.A numerical simulation is conducted to study the formation,propagation,and interaction of the shock wave of the composite charge for different initiation *** is found that the initiation mode obviously affects the shock-wave waveform and pressure distribution of the composite ***,it is found that the area of the overpressure distribution is greatest for internal and external simultaneous initiation,and the peak pressure of the shock wave exponentially decays,fitting the calculation formula of the peak overpressure attenuation under different initiation modes,which is obtained and verified by *** difference between numerical and experimental results is less than 10%,and the peak overpressure of both internal and external initiation is 56.12% higher than that of central single-point initiation.

关键词： Structure of composite charge Initiation mode Blast wave Cell size in calculation Numerical simulation

SCKF-STF-CN:a universal nonlinear filter for maneuver target tracking

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Journal of Zhejiang University-Science C(Computers and Electronics) 2011年第8期12卷 678-686页

作者： Quan-bo GE wen-bin li Cheng-lin wen Institute of Information and Control Hangzhou Dianzi University Hangzhou 310018 China State Key Lab of lndustrial Control Technology Zhejiang University Hangzhou 310027 China

Square-root cubature Kalman filter (SCKF) is more effective for nonlinear state estimation than an unscented Kalman *** this paper,we study the design of nonlinear filters based on SCKF for the system with one step noise correlation and abrupt state ***,we give the SCKF that deals with the one step correlation between process and measurement noises,SCKF-CN in ***,we introduce the idea of a strong tracking filter to construct the adaptive square-root factor of the prediction error covariance with a fading factor,which makes SCKF-CN obtain outstanding tracking performance to the system with target maneuver or abrupt state ***,the tracking performance of SCKF is greatly improved.A universal nonlinear estimator is proposed,which can not only deal with the conventional nonlinear filter problem with high dimensionality and correlated noises,but also achieve an excellent strong tracking performance towards the abrupt change of target *** simulation examples with a bearings-only tracking system are illustrated to verify the efficiency of the proposed algorithms.

关键词： Nonlinear system Maneuver target tracking Correlated noises Square-root cubature Kalman filter (SCKF) Strong tracking filtering (STF)

Research on the intermediate phase of 40CrMnSiB steel shell under different heat treatments

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Defence Technology（防务技术） 2021年第3期17卷 1032-1041页

作者： Wei-bing li Zhi-chuang Chen Xiao-ming Wang wen-bin li ZNDY of Ministerial Key Laboratory Nanjing University of Science and TechnologyNanjing210094China

In this study, 40 Cr Mn Si B steel cylindrical shells were tempered at 350, 500 and 600 ℃ to study the effect of tempering temperature on the dynamic process of expansion and fracture of the metal shell. A midexplosion recovery experiment for the metal cylinder under internal explosive loading was designed, and the wreckage of the casings at the intermediate phase was obtained. The effects of different tempering temperatures on the macroscopic and microscopic fracture characteristics of 40 Cr Mn Si B steel were studied. The influence of tempering temperatures on the fracture characteristic parameters of the recovered wreckage were measured and analyzed, including the circumferential divide size, the thickness and the number of the circumferential divisions. The results show that as the tempering temperature was increased from 350 to 600 ℃, at first, the degree of fragmentation and the fracture characteristic parameters of the recovered wreckage changed significantly and then became essentially consistent. Scanning electron microscopy analysis revealed flow-like structure characteristics caused by adiabatic shear on different fracture surfaces. At the detonation initiation end of the casing, fracturing was formed by tearing along the crack, which existed a distance from the initiation end and propagated along the axis direction. In contrast, the fracturing near the middle position consists of a plurality of radial shear fracture units. The amount of alloy carbide that was precipitated during the tempering process increased continuously with tempering temperature, leading to an increasing number of spherical carbide particles scattered around the fracture surface.

关键词： Explosive mechanics Mid-explosion recovery experiment Explosion and fracture Heat treatment SEM(Scanning electron microscope)fracture analysis

Experimental study on explosion dispersion process of a multi-layer composite charge under different initiation modes

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Defence Technology（防务技术） 2020年第4期16卷 883-892页

作者： Xiao-wen Hong Wei-bing li wen-bin li He-yang Xu Bo-liang Wang Wei Xiao ZNDY of Ministerial Key Laboratory Nanjing University of Science and TechnologyNanjingPR China School of Chemical Engineering Nanjing University of Science and TechnologyNanjingPR China

The influe nce of initiation modes on the explosive dispersion process of the multi-layer co mposite charge(MCC) was *** sensors and high-speed photography system were used to investigate the energy release process of an MCC with a specific *** shock wave pressure and explosive dispersion characteristics of the MCC under different initiation modes were *** forming and expanding process of the shock wave of the composite charge under different initiation modes was *** separation position of the shock wave and fireball interface was *** calculation formulas of the shock radius and overpressure of the composite charge are *** radius of the shock wave of the composite charge was significantly affected by the initiation ***,the development process of the composite explosive fireball under different initiation modes was analyzed,the variation rules of the composite charge dispersion radius and fireball dispersion velocity with time were obtained under the different initiation modes,the explosion energy release rate of composite charge under simultaneous initiation modes was the highest,and the peak overpressure under the simultaneous initiation mode was 1.61 times that of central single-point initiation.

关键词： Composite charge Initiation mode Blast wave Overpressure Dispersion radius

Fracture mechanism of a cylindrical shell cut by circumferential detonation collision

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Defence Technology（防务技术） 2021年第5期17卷 1650-1659页

作者： He-yang Xu Wei-bing li wen-bin li Qing Zhang Ya-jun Wang Xiao-wen Hong Ying Yang Nanjing University of Science and Technology Nanjing210094China Jiangsu Yongfeng Mechanics Co. LtdNanjing210094China

The failure mechanism of a cylindrical shell cut into fragments by circumferential detonation collision was experimentally and numerically investigated.A self-designed detonation wave regulator was used to control the detonation and cut the *** was found that the self-designed regulator controlled the fragment *** macrostructure and micro-characteristics of fragments revealed that shear fracture was a prior mechanism,the shell fractured not only at the position of detonation collision,but the crack also penetrated the shell at the first contact position of the Chapmen-Jouguet(C-J)*** effects of groove number and outer layer thickness on the fracture behavior were tested by *** the thickness of the outer layer was 5e18 mm,it has little effect on fragmentation of the shell,and shells all fractured at similar *** increase of the groove number reduced the fracture possibility of the first contact position of the C-J *** the groove number reached 7 with a 10 mm outer layer(1/4 model),the fracture only occurred at the position of detonation collision and the fragment width rebounded.

关键词： Detonation wave Circumferential detonation collision Fracture mechanism Fragmentation control

Adduct of magnesium tetraphenylporphyrin with aniline for colorimetric detection of SO_2

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Chinese Chemical Letters 2012年第2期23卷 208-212页

作者： li Hua liu wen bin li Fei Gao Tian Rui Huo College of Chemical Engineering Inner Mongolia University of TechnologyHuhhot 010051China

Adduct of magnesium tetraphenylporphyrin（MgTPP） with aniline for colorimetric detection of SO_2 was investigated in CH_2C1_2 by steady-state fluorescence and UV-vis absorption spectroscopic *** UV-vis spectra showed that the increasing aniline concentrations resulted in red shift of 3 nm for MgTPP Soret absorption *** introduced,SO_2 competes with MgTPP for aniline,which eventually leads to the release of MgTPP and changes in the solution color/*** fluorescence spectra suggested that MgTPP interacted with aniline to form 1：1 molecular adducts,and showed that the binding of MgTPP with aniline with the binding constants of 1.58-1.64 is not only endothermal but entropy-driven withΔH = 1.622 kJ mol^（-1）, AS = 9.389 J mor^（-1） K^（-1）,and AG = -1.585 kJ mol^（-1） at T= 298.15 K.

关键词： Magnesium tetraphenylporphynn(MgTPP) Aniline Spectroscopy Thermodynamic

Infectivity Analysis of Cloned Genomic DNA of P1 Agent in vitro

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畜牧兽医学报 2009年第S1期40卷 43-46页

作者： wen li-bin HE Kong-wang YANG Han-chun Institute of Veterinary Medicine Jiangsu Academy of Agricultural Sciences College of Veterinary Medicine China Agricultural University

The ultrastructure of porcine kidney(PK)-15 cells was examined after lipofectamine-aided transfection of the molecular clone of the P1 ***-15 cells transfected with the tandem dimer of the P1molecular DNA clone had numbers of intracytoplasmic inclusions,and a few cells had intranuclear *** inclusions were round to oval and 0.1-0.3μm in diameter,and intranuclear inclusions,which were more electron dense,were of two general types:the first were round and small(0.1μm approximately)and the second were hexagonal and larger(0.4-0.8μm in diameter).Cells transfected with the tandem dimer of the P1 molecular DNA clone tested positive for P1 DNA at passage *** is the first report that the P1 molecular clone has infectivity in vitro and it will provide fundamental materials for further study of the biological characterization of P1.

关键词： P1 agent molecular clone in vitro infectivity analysis

Association between CYP24A1 polymorphisms and the risk of colonic polyps and colon cancer in a Chinese population

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World Journal of Gastroenterology 2017年第28期23卷 5179-5186页

作者： Xue-Qi Chen Jia-Yu Mao wen-bin li Jian li Hong Yang Jia-Ming Qian Jing-Nan li Department of Gastroenterology Peking Union Medical College Hospital Department of General Surgery Henan Cancer Hospital

AIM To determine the pathogenesis and potential single nucleotide polymorphisms(SNPs) as screening sites for colonic polyps,colon cancer and ulcerative colitis,and to analyze the possible association between these genetic polymorphisms and the three diseases. METHODS We evaluated genetic polymorphisms in 144 newly diagnosed colonic polyp patients,96 colon cancer patients and 44 ulcerative colitis patients. The four SNPs genotyped were rs4809957,rs6068816,rs6091822 and rs8124792. The control group consisted of 504 East Asians enrolled in the 1000 Genomes Project. Correlations between CYP24A1 SNPs and the diseases were analyzed by Fisher's exact probability *** CYP24A1 polymorphisms rs4809957 A/G and rs6068816 C/T showed a statistically significant association with risk of the three diseases,when both the genotypes and allele frequencies were considered. With regard to rs6091822 G/T,all three diseases were related to risk allele carriers(GT + TT) vs wild-type(GG),but the associations between the allele frequencies and the diseases were not significant. The risk of colonic polyps and colon cancer was related to the allele frequencies of rs8124792 G/A,and this association remained for genotype frequencies of this SNP. CONCLUSION Four SNPs are related to the risk of colonic polyps and colon cancer. G allele in rs6091822 G/T may play an anti-cancer role only if it is homozygous. The A allele,which is a minor component of rs8124792,may be indicated in the diagnosis of colonic polyps or colon cancer rather than ulcerative colitis.

关键词： CYP24A1 Single nucleotide polymorphisms Colonic polyps Colon cancer