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Chinese Journal of Polymer Science 2007年第6期25卷 573-579页

作者： Ang-ran Wang yong-zhong bao Zhi-xue Weng Zhi-ming Huang State Key Laboratory of Chemical Engineering Zhejiang University Hangzhou 310027 China

An exfoliated layered double hydroxides/poly（methyl methacrylate）（LDHs/PMMA） nanocomposite was prepared by in situ solution polymerization of methyl methacrylate （MMA） in the presence of 4-vinylbenzenesulfonate intercalated LDHs（MgAl-VBS LDHs）. MgAl-VBS LDHs was prepared by the ion exchange method, and the structure and composition of the MgAl-VBS LDHs were determined by X-ray diffraction （XRD）, infrared spectroscopy and elemental analysis. XRD and transmission electron microscopy （TEM） were employed to examine the structure of LDHs/PMMA nanocomposite. It was indicated that the LDHs layers were well exfoliated and dispersed in the PMMA matrix. The grafting of PMMA onto LDHs was confirmed by the extraction result and the weight fraction of grafted PMMA increased as the weight fraction of LDHs in the nanocomposites increased.

关键词： Nanocomposite Poly(methyl methacrylate) Layered double hydroxides.

Temperature-dependent Crystallization and Phase Transition of Poly(L-lactic acid)/CO_(2) Complex Crystals

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Chinese Journal of Polymer Science 2021年第4期39卷 484-492,I0007页

作者： Ying Zheng Cai-Liang Zhang yong-zhong bao Guo-Rong Shan Peng-Ju Pan State Key Laboratory of Chemical Engineering College of Chemical and Biological EngineeringZhejiang UniversityHangzhou 310027China Institute of Zhejiang University-Quzhou Quzhou 324000China

Semicrystalline polymers can crystallize in the unique crystalline polymorph and show different phase behaviors under the high-pressure CO_(2) *** such unique crystallization and phase transition behavior is of fundamental importance for the CO_(2)-assisited processing of semicrystalline ***,we investigated the polymorphic crystalline structure,phase transition,and structure-property relationships of poly(L-lactic acid)(PLLA)treated by CO_(2) at different pressures(1-13 MPa)and crystallization temperatures(Tc's,10-110℃).PLLA crystallized in the PLLA/CO_(2) complex crystals under 7-13 MPa CO_(2) at TCS50℃but the common a crystals under the high-pressure CO_(2) at TC≥70℃.Solid-state nuclear magnetic resonance analysis indicated that the PLLA/CO_(2) complex crystals possessed weaker interactions between the PLLA chains than the common a *** PLLA/CO_(2) complex crystals were metastable and transformed into the thermally stable a crystals via the solid-to-solid route during heating or annealing at the temperature above 50℃.The complex crystals of PLLA produced at low Tc was more ductile than the a crystals due to the lower crystallinity and the plasticizing effect of CO_(2).

关键词： Poly(lactic acid) CO_(2) Complex crystal Phase transition

Optimal V_(2)O_(3) extraction by sustainable vanadate electrolysis in molten salts

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Tungsten 2024年第1期6卷 141-149页

作者： bao-Yan Feng zhong-Hua Zhao yong-Zheng Jia Jia-Liang An Ming-yong Wang State Key Laboratory of Advanced Metallurgy University of Science and Technology BeijingBeijing 100083China Beijing Key Laboratory of Green Recovery and Extraction of Rare and Precious Metals University of Science and Technology BeijingBeijing 100083China

Recently,an environmentally friendly electrolysis process of soluble vanadates is proposed and successfully confirmed for V_(2)O_(3) *** this paper,the solubilities of various vanadates(***_(3),Na_(4)V_(2)O_(7) and Na_(3)VO_(4))in NaCl molten salt are *** dependences of V_(2)O_(3) extraction on vanadate form,anode material and molten salt system are studied.A long-term electrolysis is carried *** result indicates that the solubilities of all vanadates are high and meet electrolytic *** to Na_(4)V_(2)O_(7) and Na_(3)VO_(4),NaVO_(3) exhibits larger current efficiency and lower electricity *** using SnO_(2) anode instead of graphite anode,the current efficiency of NaVO_(3) electrolysis can be increased to 58.1%and carbon pollution is avoided at 700℃.The extraction rate of V_(2)O_(3) reaches 81.3%after long-term electrolysis of 51 *** work optimizes the electrochemical preparation process of V_(2)O_(3) from various vanadates and contributes to the improvement of current efficiency and extraction rate.

关键词： Molten salt electrolysis Vanadate Vanadium trioxide Current efficiency

SYNTHESIS AND PROPERTIES OF ACRYLIC-BASED SUPERABSORBENTS WITH ENHANCED CROSSLINKING ON PARTICLE SURFACE

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Chinese Journal of Polymer Science 2005年第5期23卷 463-469页

作者： Jian Huang Zhi-ming Huang yong-zhong bao Zhi-xue Weng State Key Laboratory of Polymer Reaction Engineering,Zhejiang University,Hangzhou 310027,China Zhejiang Univ State Key Lab Polymer React Engn Hangzhou 310027 Peoples R China

A series of acrylic-based superabsorbent resins were synthesized by inverse suspension polymerization, using potassium persulfate as the initiator, N, N＇-methylene bisacrylamide （BIS） and divinylbenzene （DVB） as the multiple crosslinking agents. The morphology of the resulting superabsorbent resins revealed by SEM demonstrated that a hard shell layer was indeed formed due to surface crosslinking. The swelling and deswelling properties, and the mechanical strength of superabsorbents were investigated. The results indicated that the adding time of DVB and the amount of DVB participated in the crosslinking show a significant influence on the properties of superabsorbents. When DVB was added in polymerization later, the amount of DVB participated in reaction decreases and the surface crosslinked shell becomes thinner. It is suitable for DVB to be introduced in the later stage of the polymerization process, because the absorption rate of resin is efficiently improved in conjunction with higher water absorption. Furthermore, it was found that the mechanical strength of swollen superabsorbent with surface crosslinking was indeed enhanced in comparison with that of the conventional one.

关键词： Superabsorbet Inverse suspension polymerization Water absorption Surface crosslinking Mechanical strength.

A novel weld-pool-length monitoring method based on pixel analysis in plasma arc additive manufacturing

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Advances in Manufacturing 2024年第2期12卷 335-348页

作者： bao-Ri Zhang yong-Hua Shi Bionic Robot Research Department Ji Hua LaboratoryFoshan528200GuangdongPeople’s Republic of China Guangdong Provincial Engineering Research Center for Special Welding Technology and Equipment School of Mechanical and Automotive EngineeringSouth China University of TechnologyGuangzhou510640People’s Republic of China

The real-time monitoring of the weld pool during deposition is important for automatic control in plasma arc additive *** obtain a high deposition accuracy,it is essential to maintain a stable weld pool *** this study,a novel passive visual method is proposed to measure the weld pool *** the proposed method,the image quality was improved by designing a special visual system that employed an endoscope and a *** also includes pixel brightness-based and gradient-based algorithms that can adaptively detect feature points at the boundary when the weld pool geometry *** algorithm can also be applied to materials with different solidification *** was performed to measure the real weld pool length in world coordinates,and outlier rejection was performed to increase the accuracy of the ***,tests were carried out on the intersection component,and the results showed that the proposed method performed well in tracking the changing weld pool length and was applicable to the real-time monitoring of different types of materials.

关键词： Plasma arc additive manufacturing(PAAM) Weld pool geometry Gradient analysis Real-time detection

Barrier Option Pricing in Regime Switching Models with Rebates

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Acta Mathematicae Applicatae Sinica 2024年第3期40卷 849-861页

作者： Yue-xu ZHAO Jia-yong bao School of Economics Hangzhou Dianzi UniversityHangzhou 310018China School of Sciences Hangzhou Dianzi UniversityHangzhou 310018China

This paper is concerned with the valuation of single and double barrier knock-out call options in a Markovian regime switching model with specific *** integral formulas of the rebates are derived via matrix Wiener-Hopf factorizations and Fourier transform techniques,also,the integral representations of the option prices are ***,the first-passage time density functions in two-state regime model are *** applications,several numerical algorithms and numerical examples are presented.

关键词： option pricing Markovian regime switching Wiener-Hopf factorization Fourier transform

Miniaturized power detection module operating in millimeter wave band

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Journal of Electronic Science and Technology 2024年第2期22卷 69-76页

作者： Xiang Zhou Zhi-yong zhong School of Electronic Science and Engineering University of Electronic Science and Technology of ChinaChengdu611731China

The miniaturized broadband detection module can be embedded into the microwave application system such as the front end of the transmitter to detect the power or other parameters in real *** is highly prospective in military and scientific *** this paper,a broadband power detection module operating at 26.5 GHz-40.0 GHz is designed by using low-barrier Schottky diode as the detector and a comparator for threshold *** module can dynamically detect the power range between-10 dBm and 10 dBm with the detection accuracy of 0.1 ***,the temperature compensation circuit is also applied to improve the measurement *** a result,the resulted error low to±1 dB in the temperature range of -55℃ to +85℃ is *** designed module is encapsulated by a Kovar alloy with a small volume of 9 mm×6 mm×3 *** endows the designed module the advantages of small size,easy integration,and low cost,and even it is applicable to high-reliability environments such as satellites.

关键词： Diode Miniaturization Power detection Temperature compensation

Modelling and Temperature Control of Liquid Cooling Process for Lithium-Ion Battery

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Journal of Thermal Science 2024年第5期33卷 1794-1808页

作者： LI Guanru zhong Yangfan bao Chujin CHEN yongping ZHANG Chengbin School of Energy and Environment Southeast UniversityNanjing 210096China Key Laboratory of Efficient Low-Carbon Energy Conversion and Utilization of Jiangsu Provincial Higher Education Institutions Suzhou University of Science and TechnologySuzhou 215009China Alibaba Cloud Computing Co.Ltd. Hangzhou 311121China Zhejiang Immertech Co.Ltd. Hangzhou 310000China

Efficient thermal management of lithium-ion battery,working under extremely rapid charging-discharging,is of widespread interest to avoid the battery degradation due to temperature rise,resulting in the enhanced ***,thermal management of lithium-ion battery has been performed via a liquid cooling theoretical model integrated with thermoelectric model of battery packs and single-phase heat *** to alleviate the battery temperature fluctuation by automatically manipulating the flow rate of working fluid,a nominal model-free controller,i.e.,fuzzy logic controller is *** optimized on-off controller based on pump speed optimization is introduced to serve as the comparative *** control simulations are conducted under regular operating and extreme operating conditions,and two controllers are applied to control battery temperature with proper intervals which is conducive to enhance the battery charge-discharge *** results indicate that,for any operating condition,the fuzzy logic controller shows excellence in terms of the tracking accuracy of set-point of battery *** to the establishment of fuzzy set and fuzzy behavioral rules,the battery temperature has been throughout maintained near the set point,and the temperature fluctuation amplitude is highly reduced,with better temperature control accuracy of~0.2℃(regular condition)and~0.5℃(extreme condition)compared with~1.1℃(regular condition)and~1.6℃(extreme condition)of optimized on-off *** in the case of extreme operating condition,the proposed optimized on-off controller manifests the hysteresis in temperature fluctuation,which is ascribed to the set of dead-band for the feedback *** simulation results cast new light on the utilization and development of model-free temperature controller for the thermal management of lithium-ion battery.

关键词： temperature control battery thermal management model-free controller fuzzy logic control

Effect of Mo and cold forging deformation on strength and ductility of cobalt-based alloy L605

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Journal of Iron and Steel Research International 2024年第7期31卷 1811-1823页

作者： zhong-lin Wang Zhi-hua Gong Quan Li Han-sheng bao School of Materials and Metallurgy Inner Mongolia University of Science and TechnologyBaotou 014017Inner MongoliaChina Institute of Special Steels Central Iron and Steel Research Institute Co.Ltd.Beijing 100081China

Mo element was added to cobalt-based alloy L605,and cold forging deformation was *** effects of the addition and cold forging deformation on the microstructure and mechanical properties of the alloy were studied by thermodynamic calculation,electron backscatter diffraction,transmission electron microscopy,and X-ray *** stacking fault energy(SFE)of the alloy decreased after the addition,and the formation of stacking faults and intersections were promoted to improve the strength and *** tensile strength of the alloy with Mo increased from 1190 to 1702 MPa after 24%cold deformation,producing significant work *** strengthening mechanism is strain-induced martensitic transformation(SIMT)and deformation *** alloy,combined with Mo and after 24%deformation,had both high strength and ductility in comparison with the original cobalt-based alloy *** is attributed to the lower SFE which caused the increase in stacking fault *** the tensile process,theε-hcp phase was easily generated at the stacking fault to reduce the stress concentration and increase the *** SIMT by adjusting the density of stacking faults can improve the mechanical properties of cobalt-based ***ε-hcp phase,the interaction between deformation twins and dislocations,and the interaction between e-hcp phases during cold forging deformation caused local stress concentration,lowering ductility and toughness.

关键词： Cobalt-based alloy-Stacking fault energy Strain-induced martensitic transformation Deformation twin Cold forging deformation

Experimental and numerical study of hypervelocity impact damage on composite overwrapped pressure vessels

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Defence Technology（防务技术） 2024年第1期31卷 58-72页

作者： yong-Pan Duan Run-Qiang Chi bao-Jun Pang Yuan Cai Hypervelocity Impact Research Center Harbin Institute of TechnologyHarbin150080China College of Science Heilongjiang University of Science and TechnologyHarbin 150022China

Ground-based tests are important for studying hypervelocity impact(HVI)damage to spacecraft pressure vessels in the orbital debris *** analyzed the damage to composite overwrapped pressure vessels(COPVs)in the HVI tests and classified the damage into non-catastrophic damage and catastrophic *** proposed a numerical simulation method to further study non-catastrophic damage and revealed the characteristics and mechanisms of non-catastrophic damage affected by impact conditions and internal *** fragments of the catastrophically damaged COPVs were collected after the *** crack distribution and propagation process of the catastrophic ruptures of the COPVs were *** findings contribute to understanding the damage characteristics and mechanisms of COPVs by HVIs.

关键词： Orbital debris Hypervelocity impact Composite overwrapped pressure vessels Damage mechanisms