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Chinese Journal of Polymer Science 2019年第8期37卷 834-840页

作者： Jing Li Shao-Hua Jin Guan-chao Lan Zi-Shuai Xu Lu-Ting Wang Na Wang Li-Jie Li School of Materials Science and Engineering Beijing Institute of Technology Beijing 100081 China Research institute of Gansu Yin Guang Chemical Industry Group Co.ltd Baiyin 730900 China

To effectively improve the performance and expand the applications of polymers, molecular dynamics(MD) simulations with the COMPASS force field have been applied to predict the miscibility, glass transition temperature(Tg), and mechanical properties of poly(vinyl chloride)/dioctyl phthalate(PVC/DOP) blends. The solubility parameter values obtained are in good agreement with the reference data and the little difference(|Δδ|< 2.0 MPa0.5) between two components indicates that PVC/DOP is a miscible system. Tg is predicted by the slope of the free volume and density versus temperature simulation data based on density and free volume theory which is agree well with the experimental data. In addition, the analyses of mechanical properties results indicate that the values of Young’s modulus(E), bulk modulus(K), and shear modulus(G) decrease with the addition of DOP, demonstrating that the rigidity of material is weakened and the ductility is improved. The mechanical properties can also be effectively improved by increasing the temperature, which may provide a more flexible mixture, with lower E, K, G but an increased ductility.

关键词： Poly(vinyl chloride)(PVC) Dioctyl phthalate (DOP) MD simulations Glass transition temperature Mechanical properties

Industrial Application and Fundamental Research Progress on Fluid Catalytic Cracking Technology of Downer Reactors

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China Petroleum Processing & Petrochemical Technology 2022年第3期24卷 139-150页

作者： Liu Wenming Yuan Qimin Zhu Genquan Yang chao SINOPEC Research institute of Petroleum Processing Co. Ltd.Beijing 100083

Fluid catalytic cracking(FCC)technologies of downer reactors,which have reached the demonstration or commercial scale,are systematically discussed,i.e.,millisecond catalytic cracking,fluidization lab of Tsinghua University,and high-severity ***,aiming to promote industrial application,the fundamental studies are comprehensively described,particularly focusing on high-density downer reactors,clusters,and ***,from the perspective of industrial application,some research directions toward further developments are suggested.

关键词： fluid catalytic cracking downer reactor light olefins clean gasoline

Impurities analysis of high-purity osmium target for M-cathode application

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Rare Metals 2023年第4期42卷 1154-1159页

作者： Jun-Da Ma Yang Xia Yuan-Feng Xie chao Zhang GRIMAT Engineering institute Co. LtdBeijing101407China State Key Laboratory of Advanced Materials for Smart Sensing GRINM Group Co.LtdBeijing101407China General Research institute for Nonferrous Metals Beijing100088China

Impurities and their distributions in osmium targets for M-type cathodes affect the coating quality on porous tungsten and cathode emission *** discharge mass spectrometry(GDMS)and X-ray photoelectron spectroscopy(XPS)were used to analyze the impurity contents and distributions in the osmium *** chemical states of impurity elements were analyzed and *** total amount of metallic impurity in the target was lower than 0.01 wt%.

关键词： osmium Impurities purity

Magnetoelastic Anisotropy of FeSiB Glass-Coated Amorphous Microwires

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Chinese Physics Letters 2013年第1期30卷 184-186页

作者： LIU Kai-Huang LU Zhi-chao LIU Tian-Cheng LI De-Ren China Iron and Steel Research institute Group Advanced Technology and Materials Co.Ltd.Beijing 100081

The magnetoelastic anisotropy of Fe77.5Si7.5B15 glass-coated amorphous microwires is investigated by the law of approach to saturation magnetization in comparison with the ferromagnetic resonance *** anisotropy field of the inner core determined by the former method is 7.6×10^(4) A/m,which is larger than the value 2.5×10^(4) A/m measured by the ferromagnetic resonance *** difference is ascribed to the skin effect and the uneven distribution of the internal ***,the anisotropy field of the outer shell has a negative value indicating that it has an easy basal plane.

关键词： technique. anisotropy value

Fluorinated semi-interpenetrating polymer networks for enhancing the mechanical performance and storage stability of polymer-bonded explosives by controlling curing and phase separation rates

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Defence Technology（防务技术） 2024年第8期38卷 58-66页

作者： chao Deng Huihui Liu Yongping Bai Zhen Hu School of Chemistry and Chemical Engineering Harbin Institute of TechnologyHarbin 150000China Wuxi HIT New Material Research institute Co. Ltd.Wuxi 214000China institute of Chemical Materials China Academy of Engineering PhysicsMianyang 621900China

Herein, the effect of fluoropolymer binders on the properties of polymer-bonded explosives(PBXs) was comprehensively investigated. To this end, fluorinated semi-interpenetrating polymer networks(semiIPNs) were prepared using different catalyst amounts(denoted as F23-CLF-30-D). The involved curing and phase separation processes were monitored using Fourier-transform infrared spectroscopy, differential scanning calorimetry, a haze meter and a rheometer. Curing rate constant and activation energy were calculated using a theoretical model and numerical method, respectively. Results revealed that owing to its co-continuous micro-phase separation structure, the F23-CLF-30-D3 semi-IPN exhibited considerably higher tensile strength and elongation at break than pure fluororubber F2314 and the F23-CLF-30-D0 semi-IPN because the phase separation and curing rates matched in the initial stage of *** arc Brazilian test revealed that F23-CLF-30-D-based composites used as mock materials for PBXs exhibited excellent mechanical performance and storage stability. Thus, the matched curing and phase separation rates play a crucial role during the fabrication of high-performance semi-IPNs;these factors can be feasibly controlled using an appropriate catalyst amount.

关键词： Semi-interpenetrating polymer networks Fluoropolymer Curing rate Phase separation rate Polymer-bonded explosives

Domain Structure and Magnetization Process in Short Glass-Coated Amorphous Microwires with Positive Magnetostriction

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Chinese Physics Letters 2012年第10期29卷 209-212页

作者： LIU Kai-Huang LU Zhi-chao LI De-Ren LIU Tian-Cheng ZHOU Shao-Xiong China Iron and Steel Research institute Group Advanced Technology and Materials Co.Ltd.Beijing 100081

The domain structure and magnetisation process in short glass-coated amorphous Fe45Co20Ni10Si9B16 microwires are investigated by analyzing the hysteresis loops measured by a vibrating sample *** of calculating the thickness of the outer shell and the critical length to observe magnetic bistability have been *** thickness of the outer shell is 2.3μm and the critical length is 8.11 mm for a microwire with a metallic core diameter of 31.1μm and a glass coat thickness of 10.6μ*** experimental results demonstrate the reliability of this method to calculate the critical length.

关键词： critical outer magnetometer

GPU-accelerated scanning path optimization in particle cancer therapy

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Nuclear Science and Techniques 2019年第4期30卷 27-34页

作者： chao Wu Yue-Hu Pu Xiao Zhang Shanghai institute of Applied Physics Chinese Academy of Sciences Shanghai APACTRON Particle Equipment Co.ltd

When using the beam scanning method for particle beam therapy, the target volume is divided into many iso-energy slices and is irradiated slice by slice. Each slice may comprise thousands of discrete scanning beam positions. An optimized scanning path can decrease the transit dose and may bypass important organs. The minimization of the scanning path length can be considered as a variation of the traveling salesman problem; the simulated annealing algorithm is adopted to solve this problem. The initial scanning path is assumed as a simple zigzag path;subsequently, random searches for accepted new paths are performed through cost evaluation and criteria-based judging. To reduce the optimization time of a given slice,random searches are parallelized by employing thousands of threads. The simultaneous optimization of multiple slices is realized by using many thread blocks of generalpurpose computing on graphics processing units *** on a computer with an Intel i7-4790 CPU and NVIDIA K2200 GPU, our new method required only 1.3 s to obtain optimized scanning paths with a total of 40 slices in typically studied cases. The procedure and optimization results of this new method are presented in this work.

关键词： Particle beam therapy Treatment planning Scanning path optimization

Amorphous FeNiCoCuSiBCr Alloys with Superior Direct Current Tolerant Characteristics

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Journal of Iron and Steel Research International 2015年第2期22卷 145-149页

作者： Xiao-rong WU De-ren LI Zhun LI Zhi-chao LU China Iron and Steel Research institute Group Advanced Technology and Materials Co. Ltd.

Amorphous Fe62-x Ni19CoxCu0.1 Si3.8B14Cr1. 1 （x=0, 1, 5, 10） ribbons were annealed under magnetic field and tensile stress, respectively, and their magnetic properties were investigated. Fe73.5 Cu1 Nb3 Si15.5 B7 and Fe66 Ni10- Cu1 Nb3Si11 B9 nanocrystalline alloy ribbons were also fabricated for comparison. Excellent DC tolerant property was obtained in the amorphous FeNiCoCuSiBCr ribbons after thermomagnetic treatment and the constant permeable property was improved with increasing Co content. The relative permeability was constant up to the DC bias field of approximately 6 ×10 ^-4 , 9 ×10 ^-4, and 10 × 10^-4 T and the values of relative permeability μ were 1 650, 1 200, and 1 000 with the Co content being 0, 5 at. %, and 10 at.%, respectively. Besides, stress-annealed FeNiCoCuSiBCr al- loy ribbons were proved to exhibit positive saturation magnetostriction constant λs.

关键词： Fe based amorphous alloy magnetic property field annealing stress annealing domain structure

Magnetic Properties of Nanocrystalline Powder Cores Fabricated by Mechanically Crushed Powders

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Journal of Iron and Steel Research International 2015年第1期22卷 67-71页

作者： Chun-bo HUANG Tian-cheng LIU Xiang-yue WANG Cao-wei LU De-ren LI Zhi-chao LU China Iron and Steel Research institute Group Advanced Technology and Materials Co. Ltd.

Fe73. 5 Cu1 Nb3 Si15.5B7 nanocrystalline powder cores with different particle sizes ranging from 10 to 125 9m were fabricated by cold-pressing techniques. The cores exhibited increased core loss P cv and decreased initial permea- bility μi with addition of fine powders below 50 μm in size, and the content should be less than 40 mass%. It was thought to be closely related to the high coercive force H c due to the stresses generated during the crushing process and high demagnetization fields of small powders. Furthermore, modifying the alloy compositions by adding defined amount of Ni could improve the soft magnetic properties, including superior characteristics of permeability under high direct current （DC） bias field and comparable low core loss at high frequency.

关键词： nanocrystalline powder core mechanical crush particle size DC bias

Byzantine Fault-Tolerant Routing for Large-Scale Wireless Sensor Networks Based on Fast ECDSA

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Tsinghua Science and Technology 2015年第6期20卷 627-633页

作者： Jiawei Xu Keda Wang chao Wang Feng Hu Zhenhua Zhang Shiyi Xu Jie Wu Department of Communication and Information Engineering Shanghai University China Information Security Research institute ltd. Huawei institute of Computer Engineering and Science Shanghai University Department of Computer and Information Sciences Temple University

Wireless sensor networks are a favorite target of Byzantine malicious attackers because of their limited energy, low calculation capability, and dynamic topology, and other important characteristics. The Byzantine Generals Problem is one of the classical problems in the area of fault tolerance, and has wide application, especially in distributed databases and systems. There is a lot of research in agreement and replication techniques that tolerate Byzantine faults. However, most of this work is not suited to large-scale wireless sensor networks, due to its high computational complexity. By introducing Fast ECDSA(Elliptic Curve Digital Signature Algorithm), which can resist timing and energy attacks, and reduce the proportion of verifying signature algorithm to generating signature algorithm to 1.2 times, we propose a new Byzantine fault-tolerant routing algorithm for large-scale wireless sensor networks with double-level hierarchical architecture. In different levels, the algorithm runs different BFT *** and simulation results have proved that this algorithm has high security and the number of communication rounds between clusters is reduced by 1/3, which balances the network load. At the same time, the application of Fast ECDSA improves the security level of the network without burdening it.

关键词： wireless sensor networks Byzantine Generals Proble