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Preparation of MMA-BA-DMAEMA Nanosized Latex

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Chinese Chemical Letters 2003年第8期14卷 863-865页

作者： yu yang liu Mu Jie yang Department of Polymer Science and Engineering ZhejiangUniversityHangzhou 310027

The terpolymer latex of methyl methacrylate (MMA)/butyl acrylate (BA)/ dimethyl aminoethyl methacrylate (DMAEMA) with diameter of less than 100 nm was prepared by seeding semi-continuous emulsion copolymerization using APS (ammonium persulfate) / TMEDA (N,N,N, N-tetramethylethylenediamine) as the redox initiators and SDS (sodium dodecylsulfate) and OP (P-octylpolyethylene glycol phenylether) as co-emulsifiers. The factors that influenced the process stability of the copolymerization and the particle size of the latex were investigated. The addition of aqueous ammonia as coagulation inhibitor provided better process stability of the copoly- merization. The addition of acetic acid as the acidification agent caused a remarkable reduction of the latex particle size.

关键词： Emulsion copolymerization dimethylaminoethyl methacrylate stablity nanosize.

Electrolytic silicon/graphite composite from SiO_(2)/graphite porous electrode in molten salts as a negative electrode material for lithium-ion batteries

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Rare Metals 2022年第2期41卷 438-447页

作者： Ning Wang yu-yang liu Zhi-Xia Shi Zhang-Long yu Hua-Ying Duan Sheng Fang Juan-yu yang Xing-Ming Wang GRIREM Advanced Materials Co. Ltd.China Automotive Battery Research Institute Co.Ltd.General Research Institute for Nonferrous MetalsBeijing 100088China GRINM Resources and Environment Tech.Co.Ltd. General Research Institute for Nonferrous MetalsBeijing 100088China China Automotive Battery Research Institute Co.Ltd. General Research Institute for Nonferrous MetalsBeijing 100088China

Nano-silicon(nano-Si)and its composites have been regarded as the most promising negative electrode materials for producing the next-generation Li-ion batteries(LIBs),due to their ultrahigh theoretical ***,the commercial applications of nano Si-based negative electrode materials are constrained by the low cycling stability and high *** molten salt electrolysis of SiO_(2)is proven to be suitable to produce nano-Si with the advantages of in-situ microstructure control possibilities,cheap affordability and scale-up process ***,an economical approach for electrolysis,with a SiO_(2)/graphite porous electrode as cathode,is adopted to produce nano-Si/graphite composite negative electrode materials(SGNM)in this *** electrolytic product of the optimized porous electrode is taken as the negative electrode materials for LIBs,and it offers a capacity of 733.2 mAh·g^(-1)and an initial coulombic efficiency of 86.8%in a coin-type ***,the capacity of the SGNM retained 74.1%of the initial discharging capacity after 50 cycles at 0.2C,which is significantly higher than that of the simple mixture of silicon and graphite obtained from the formation of silicon carbide(SiC)between nano-Si and graphite ***,this new approach can be applied to a large-scale production.

关键词： Li-ion battery Negative electrode materials Molten salt electrolysis Nano-silicon

Effects of recrystallization on the low cycle fatigue behavior of directionally solidified superalloy DZ40M

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Rare Metals 2008年第4期27卷 425-428页

作者： ZHAO yang WANG Lei LI Hongyun yu Teng liu yang Key Laboratory of the Ministry of Education of China for Anisotropy and Texture of Materials Northeastern University Shenyang 110004 China

The effects of recrystallization on low cycle fatigue behavior were investigated on directionally solidified Co-base superalloy DZ40M. Optical microscopy and SEM were used to examine the microstructure and fracture surface of the specimens. The mechanical testing results demonstrated that the low cycle fatigue property of DZ40M significantly decreased with the partial recrystallization. Fatigue cracks initiate near the carbides and the grain boundaries with slip-bands. Both the fatigue crack initiation and propagation can be accelerated with the occurrences of recrystallized grain boundaries.

关键词： Co-base superalloy low cycle fatigue recrystallization crack initiation crack propagation

Synthesis and Crystal Structure of 4,4′-Diamino-N,N′-diethyl Bisbenzenesulfamide

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Chinese Journal of Structural Chemistry 2007年第2期26卷 177-183页

作者： WANG Li-Min PAN Xiao-Juan FAN Zhao-yu yang liu-Bo liu Lian TIAN He Laboratory for Advanced Materials Institute of Fine ChemicalsEast China University of Science and Technology Shanghai 200237 China

A new compound of 4,4＇-diamino-N,V＇-diethyl bisbenzenesulfamide （C18H26N4O4S2, Fw = 426.55） has been synthesized and its structure was determined by X-ray crystallography method. The crystal belongs to the monoclinic system, space group P21/c with a = 10.0623（9）, b = 13.6759（13）, c =15.5309（14） A, β = 100.482（2）°, V= 2101.6（3） A^3, Dc = 1.348 g/cm^3, F（000） = 904, μ = 0.285 mm^-1, Z = 4, the final R = 0.0512 and wR = 0.1363 for 3485 observed reflections with I 〉 2σ（I）. The structure of the title compound is pseudo secondary axisymmetric, and the two sulfamide-groups show distorted tetrahedral configurations.

关键词： 4,4'-diamino-N,V'-diethyl bisbenzenesulfamide synthesis crystal structure

Synthesis and densification of zirconium diboride prepared by carbothermal reduction

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Rare Metals 2018年第12期37卷 1076-1081页

作者： Tao Gui Xing-Ming Wang Lei yang yu-yang liu Xue Bai Li-Jun Wang Bo Song Division of Metallurgy and Materials for Rare Metals General Research Institute for Nonferrous Metals School of Metallurgical and Ecological Engineering University of Science and Technology Beijing

Using boron powder as additive, the preparation of zirconium diboride(ZrB 2) by carbothermal reduction was investigated. The results show that the carbothermal reduction cannot be completely done until the temperature is more than 1900 ℃. The ZrB2 particles prepared without boron(B) additive at 1900 ℃ for 3 h are rodlike and show a preferential grain growth along [001] direction. B additive changes the heat effect of the raw materials. With B additive, the morphology of ZrB2 particles turns to be regular shape. The average particle size is about 3.6 μm with 2.5 wt% B additives. With more B additive, the shape of particles turns to be round like and the average particle size is decreased to 2.3 μm when 5 wt% B is added. The existence of oxides in grain boundary is a key factor to keep ZrB2 ceramic from deep densification. Using ZrB2 powder prepared with 5 wt% B additives, by controlling carbon content in ZrB2 powder, ZrB2 ceramic with 93%relative density is hot-pressed.

关键词： Zirconium diboride Carbothermal reduction Grain growth Morphology control Deep densification

Diagnostic accuracy of a deep learning approach to calculate FFR from coronary CT angiography

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Journal of Geriatric Cardiology 2019年第1期16卷 42-48页

作者： Zhi-Qiang WANG yu-Jie ZHOU Ying-Xin ZHAO Dong-Mei SHI yu-yang liu Wei liu Xiao-Li liu yue-Ping LI Department of Cardiology Beijing Anzhen Hospital Capital Medical University Beijing Institute of Heart Lung and Blood Vessel Disease Beijing Key Laboratory of Precision Medicine of Coronary Atherosclerotic Disease Clinical Center for Coronary Heart Disease Capital Medical University

Background The computational fluid dynamics(CFD)approach has been frequently applied to compute the fractional flow reserve(FFR)using computed tomography angiography(CTA).This technique is *** developed the DEEPVESSEL-FFR platform using the emerging deep learning technique to calculate the FFR value out of CTA images in five *** study is to evaluate the DEEPVESSEL-FFR platform using the emerging deep learning technique to calculate the FFR value from CTA images as an efficient *** A single-center,prospective study was conducted and 63 patients were enrolled for the evaluation of the diagnostic performance of *** quantification method for the three-dimensional coronary arterial geometry and the deep learning based prediction of FFR were developed to assess the ischemic risk of the stenotic coronary *** performance of the DEEPVESSEL-FFR was assessed by using wire-based FFR as reference *** primary evaluation factor was defined by using the area under receiver-operation characteristics curve(AUC)*** For per-patient level,taking the cut-off value<0.8 referring to the FFR measurement,DEEPVESSEL-FFR presented higher diagnostic performance in determining ischemia-related lesions with area under the curve of 0.928 compare to CTA stenotic severity ***-FFR correlated with FFR(R=0.686,P<0.001),with a mean di&ference of-0.006士0.0091(P=0.619).The secondary evaluation factors,indicating per vessel accuracy,sensitivity,specificity,positive predictive value,and negative predictive value were 87.3%,97.14%,75%,82.93%,and 95.45%,*** DEEPVESSEL-FFR is a novel method that allows efficient assessment of the functional significance of coronary stenosis.

关键词： Computed tomography angiography Coronary artery Deep learning Fractional flow reserve

A new approach for flow simulation in complex hydraulic fracture morphology and its application:Fracture connection element method

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Petroleum Science 2023年第5期20卷 3002-3012页

作者： Guang-Long Sheng Hui Zhao Jia-Ling Ma Hao Huang Hai-yang Deng Wen-Tao Zhan yu-yang liu College of Petroleum Engineering Yangtze UniversityWuhan430100HubeiChina Hubei Key Laboratory of Oil and Gas Drilling and Production Engineering(yangtze University) Wuhan430100HubeiChina China National Offshore Oil Corporation-Hainan Haikou570100HainanChina CNOOC Research Institute Ltd. Beijing100020China

Efficient flow simulation and optimization methods of hydraulic fracture morphology in unconventional reservoirs are effective ways to enhance oil/gas *** on the connection element method(CEM)and distribution of stimulated reservoir volume,the complex hydraulic fracture morphology was accurately described using heterogeneous node connection *** a new fracture connection element method(FCEM)for fluid flow in stimulated unconventional reservoirs with complex hydraulic fracture morphology was *** the proposed FCEM,the arrangement of dense nodes in the stimulated area and sparse nodes in the unstimulated area ensures the calculation accuracy and *** key parameter,transmissibility,was also modified according to the strong heterogeneity of stimulated *** finite difference and semi-analytical tracking were used to accurately solve the pressure and saturation distribution between *** FCEM is validated by comparing with traditional numerical simulation method,and the results show that the bottom hole pressure simulated by the FCEM is consistent with the results from traditional numerical simulation method,and the matching rate is larger than 95%.The proposed FCEM was also used in the optimization of fracturing parameters by coupling the hydraulic fracture propagation method and intelligent optimization *** integrated intelligent optimization approach for multi-parameters,such as perforation number,perforation location,and displacement in hydraulic fracturing is *** proposed approach was applied in a shale gas reservoir,and the result shows that the optimized perforation location and morphology distribution are related to the distribution of porosity/*** the perforation location and displacement are optimized with the same fracture number,NPV increases by 70.58%,which greatly improves the economic benefits of unconventional *** work provides a new way for flow simulation and op

关键词： Unconventional reservoirs Multi-fractured horizontal wells Complex fracture morphology Fracture connection element method Integrated optimization

The impact of female sex hormones on cardiovascular disease:from mechanisms to hormone therapy

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Journal of Geriatric Cardiology 2024年第6期21卷 669-681页

作者： Yi KAN yu-Lu PENG Ze-Hao ZHAO Shu-Tong DONG Yin-Xiao XU Xiao-Teng MA Xiao-Li liu yu-yang liu yu-Jie ZHOU Department of Cardiology Beijing Anzhen HospitalCapital Medical UniversityBeijing Institute of Heart Lung and Blood Vessel DiseaseBeijing Key Laboratory of Precision Medicine of Coronary Atherosclerotic DiseaseClinical Center for Coronary Heart DiseaseCapital Medical UniversityBeijingChina

Cardiovascular disease remains the leading cause of mortality in women,yet it has not raised the awareness from the *** pathogenesis of cardiovascular disease differs significantly between females and males concerning the effect of sex *** and progestogen impact cardiovascular system through genomic and non-genomic *** menopause,cardiovascular protective effects of estrogens have been well *** were often used in combination with estrogens in hormone *** in sex hormone levels,particularly estrogen deficiency,were considered the specific risk factor in women’s cardiovascular ***,considerable heterogeneity in the impact of hormone therapy was observed in clinical *** heterogeneity is likely closely associated with factors such as the initial time,administration route,dosage,and formulation of hormone *** review will delve into the pathogenesis and hormone therapy,summarizing the effect of female sex hormones on hypertension,pre-eclampsia,coronary heart disease,heart failure with preserved ejection fraction,and cardiovascular risk factors specific to women.

关键词： impact dosage protective

A deep-learning-based prediction method of the estimated ultimate recovery(EUR)of shale gas wells

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Petroleum Science 2021年第5期18卷 1450-1464页

作者： yu-yang liu Xin-Hua Ma Xiao-Wei Zhang Wei Guo Li-Xia Kang Rong-Ze yu yu-Ping Sun PetroChina Research Institute of Petroleum Exploration and Development(RIPED) Beijing100083China China National Shale Gas Research&Development(Experiment)Center Langfang065007HebeiChina

The estimated ultimate recovery(EUR)of shale gas wells is influenced by many factors,and the accurate prediction still faces certain *** an artificial intelligence algorithm,deep learning yields notable advantages in nonlinear ***,it is feasible to predict the EUR of shale gas wells based on a deep-learning *** this paper,according to geological evaluation data,hydraulic fracturing data,production data and EUR evaluation results of 282 wells in the WY shale gas field,a deep-learning-based algorithm for EUR evaluation of shale gas wells was designed and ***,the existing EUR evaluation methods of shale gas wells and the deep feedforward neural network algorithm was systematically ***,the technical process of a deep-learning-based algorithm for EUR prediction of shale gas wells was ***,by means of real data obtained from the WY shale gas field,several different cases were applied to testify the validity and accuracy of the proposed *** results show that the EUR prediction with high *** addition,the results are affected by the variety and number of input parameters,the network structure and *** proposed approach can be extended to other shale fields using the similar technic process.

关键词： Shale gas Estimated ultimate recovery Deep learning Deep feedforward neural network