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Cationic CO_(2)-based Waterborne Polyurethane with High Solid Content and Excellent Ageing Resistance

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Chinese Journal of Polymer Science 2022年第10期40卷 1183-1192,I0008页

作者： hong-ming zhang Guang-Ping Han Wan-Li Cheng Shun-Jie Liu Xian-hong Wang Key Laboratory of Bio-based Material Science and Technology(Ministry of Education) Northeast Forestry UniversityHarbin 150040China Key Laboratory of Polymer Ecomaterial Changchun Institute of Applied ChemistryChinese Academy of SciencesChangchun 13022China

High solid content CO_(2)-based cationic waterborne polyurethanes(CWPUs)were prepared using CO_(2)-polyols as soft segment and Nmethyl diethanolamine(MDEA)as hydrophilic *** resulting stable aqueous dispersion displayed a high solid content of 52%with a low MDEA loading of 3.52 wt%.This novel structural CWPU can provide excellent adhesive strength,whose T-peel strength could reach 173.48N/5cm,20%higher than that of ester-based cationic waterborne polyurethane(87.55 N/5cm).The CO_(2)-based CWPU film showed only 2 wt%swelling percentage after 240 min immersion in water,and no change was observed during its immersion in 5 wt%sodium hydroxide *** tensile strength of CO_(2)-WPUs dropped slowly to 91.2%after 480 min immersion in a 5 wt%sodium hydroxide solution,whereas that of esterbased CWPUs dropped quickly to 32%after 240 min and their mechanical properties were lost after 360 min ***,the retention of the tensile strength of the CO_(2)-CWPUs was 81.5%even after 720 min immersion in 10 wt%H_(2)O_(2) solution,while it was only ca.38%for the ester-based *** results indicated that the cationic CO_(2)-based CWPU may be promising waterborne adhesive with outstanding ageing resistance due to its synergistic effect from carbonate and ether groups of CO_(2)-polyol structure.

关键词： Cationic waterborne polyurethane CO_(2)-polyol High solid content Hydrolysis/oxidation resistance

Modes of multi-mechanistic gas diffusion in shale matrix at varied effective stresses:Observations and analysis

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Petroleum Science 2023年第5期20卷 2908-2920页

作者： Tian-Yu Chen Yan-Yu Hao Derek Elsworth hong-ming zhang Zhi-ming Hu Guang-Lei Cui Key Laboratory of Ministry of Education on Safe Mining of Deep Metal Mines School of Resources and Civil Engineering and Key Laboratory of Liaoning Province on Deep Engineering and Intelligent TechnologyNortheastern UniversityShenyang110819LiaoningChina National Energy Shale Gas R&D(experiment)Center Langfang065007HebeiChina Department of Energy and Mineral Engineering EMS Energy Institute and G3 CenterPennsylvania State UniversityUniversity ParkPA16802USA Research Institute of Petroleum Exploration&Development PetroChina Company LimitedBeijing100084China

Gas diffusion in the shale matrix has a dominant effect on late-stage production from shale gas ***,adequate research on the mechanisms and contributions of gas diffusion for varied pore size populations in shale matrix under recreated in situ stress is *** report gas-diffusion measurements under constant in situ stress but variable gas pressures for contrasting non-adsorbent(helium(He))and adsorbed(methane(CH_(4)))gases to investigate the impact of effective stress on the evolution of dominant mechanisms of *** intact sample replicates true pore-network topology and diffusion *** integrated diffusion model is proposed that combines the effects of slip flow,Knudsen flow,and surface diffusion to constrain the evolution of these flow regimes and their respective contributions to the observational ***,a probability density function(PDF)is employed to separate the gas content distributions of macropores and micropores from the total gas content and to investigate gas contributions in various *** results reveal that the diffusion coefficients of both He and CH_(4) in macropores and micropores increase with gas pressure but decrease with increasing effective *** diffusion coefficients of He and CH_(4) are different in macropores but remain nearly the same in *** diffusion coefficients of slip flow and surface diffusion increase with decreasing effective stress except for CH_(4) diffusion in the micropores,while the evolution of Knudsen diffusion shows the opposite *** flow plays a dominant role in He and CH_(4) diffusion within macropores(pore size 45 nm).Knudsen diffusion gradually becomes significant for He diffusion in the micropores(pore size 4 nm),conversely,for CH_(4) diffusion in the micropores,surface diffusion becomes *** to gas production from reservoirs,the contributions of the micropores will increase gradually with the duration of gas recovery,indicating the significan

关键词： Diffusion coefficient In situ stress Varied pore types Diffusion mechanisms Gas-content contributions

A Rapid Solid-phase Synthesis to Soluble Oligothiophene Molecular Wires

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Chinese Chemical Letters 2006年第4期17卷 437-440页

作者： hong ming zhang Xian hong WANG Xiao Jiang ZHAO Ji LI Fo Song WANG Polymer Material Engineering Lab Changchun Institute of Applied Chemistry CAS Changchun 130022

A novel method for the preparation of oligothiophene molecular wires is described via a bi-directional solid-phase synthesis. Using an alternating sequence of bromination and Stille coupling reactions, oligomers were ... 详细信息

关键词： Solid-phase synthesis molecular wires oligothiophene.

Biodegradation of methyl parathion by Acinetobacter radioresistens USTB-04

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Journal of Environmental Sciences 2007年第10期19卷 1257-1260页

作者： LIU Fang-yao hong ming-zhang LIU Dan-mei LI Ya-wen SHOU Pei-shun YAN Hai SHI Guo-qing Department of Biological Science and Technology School of Applied Science University of Science and Technology Beijing Beijing 100083 China

Biodegradation of methyl parathion （MP）, a widely used organophosphorus pesticide, was investigated using a newly isolated bacterium strain Acinetobacter radioresistens USTB-04. MP at an initial concentration of 1200 mg/L could be totally biodegraded by A. radioresistens USTB-04 as the sole carbon source less than 4 d in the presence of phosphate and urea as phosphorus and nitrogen sources, respectively. Biodegradation of MP was also achieved using cell-free extract of A. radioresistens USTB-04. MP at an initial concentration of 130 mg/L was completely biodegraded in 2 h in the presence of cell-free extract with a protein concentration of 148.0 mg/L, which was increased with the increase of pH from 5.0 to 8.0. Contrary to published reports, no intermediate or final degradation metabolites of MP could be observed. Thus we suggest that the cleavage of C-C bond on the benzene ring other than P-O bond may be the biodegradation pathway of MP by A. radioresistens USTB-04.

关键词： Acinetobacter radioresistens USTB-04 biodegradation methyl parathion

Effects of ground-level ozone (O_3) pollution on the yields of rice and winter wheat in the Yangtze River Delta

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Journal of Environmental Sciences 2003年第3期15卷 360-362页

作者： FENG Zong-wei, JIN ming-hong, zhang Fu-zhu, HUANG Yi-zong (Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing\ 100085, China.) Research Center for Eco-Environmental Sciences Chinese Academy of Sciences Beijing 10085 Chin

Effects of elevated O_3 on the yields of rice and winter wheat were studied by using open-top chambers(OTCs). Results showed that compared to the control treatment, 200 ppb, 100 ppb, 50 ppb treatments caused a 80.4%, 58.6% and 10.5% decrease in grain yields per winter wheat plant and a 49.1%, 26.1% and 8.2% decrease in grain yield per rice plant, respectively. According to the dose-response relation educed from OTCs experiment and the monitor data of O_3 concentrations in spots, it was estimated that the yield losses of rice and winter wheat resulted by O_3 pollution in the Yangtze River Delta region in 1999 were 0.599 million ton and 0.669 million ton, economic losses were 0.539 billion RMB Yuan and 0.936 billion RMB Yuan, respectively.

关键词： rice winter wheat O_3 Yangtze River Delta

Glomus tumor of the gastric body:helical CT findings

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Chinese Medical Journal 2007年第14期120卷 1289-1291页

作者： HU Xiao-yun HU Chun-hong FANG Xiang-ming zhang Tong-hua Medical Imaging Center First Affiliated Hospital Soochow University Suzhou 215006 China

Glomus tumors, also known as glomangiomas, are rare and originate in the neuromyoarterial glomus, a normal arteriovenous shunt which is abundantly supplied with nerve fibers and fulfills a temperature-regulating function. The classic location of glomus tumor is the subungual region, but the tumor can occur elsewhere in the skin, soft tissues, nerves, stomach, nasal cavity, and *** the gastrointestinal （GI） tract the tumor occurs more often in the stomach than other parts, and typically occurs as a solitary submucosal nodule in the antrum. We reported a case of glomus tumor originating from the greater curvature of stomach which was studied with contrast-enhanced helical computed tomography （CT） and described the characteristic helical CT findings of the rare lesion.

关键词： glomus tumor computed tomography diagnostic imaging

Strengthening mechanisms based on reinforcement distribution uniformity for particle reinforced aluminum matrix composites

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Transactions of Nonferrous Metals Society of China 2018年第12期28卷 2395-2400页

作者： Gang CHEN Jia WAN Ning HE hong-ming zhang Fei HAN Yu-min zhang School of Materials Science and Engineering Harbin Institute of Technology at WeihaiWeihai 264209China Department of Civil Engineering Harbin Institute of Technology at WeihaiWeihai 264209China School of Astronautics Harbin Institute of TechnologyHarbin 150001China

A modified mixed strengthening model was proposed for describing the yield strength of particle reinforced aluminum matrix *** strengthening mechanisms of the composites were analyzed based on the microstructures and compression mechanical *** distribution uniformity of reinforcements and cooperation relationship among dislocation mechanisms were considered in the modified mixed strengthening model by introducing a distribution uniformity factor u and a cooperation coefficient fc,*** results show that the modified mixed strengthening model can accurately describe the yield strengths of Al3Ti/2024Al composites with a relative deviation less than1.2%,which is much more accurate than other strengthening *** modified mixed model can also be used to predict the yield strength of Al3Ti/2024Al composites with different fractions of reinforcements.

关键词： metal matrix composite strengthening model yield strength reinforcement distribution uniformity

CARBOXYMETHYLPACHYMAN(Ⅰ),A NEW WATER SOLUBLE POLYSACCHARIDE WITH MARKED ANTITUMOUR ACTIVITY

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Chinese Chemical Letters 1992年第1期3卷 1-2页

作者： Zhong Yuan YU Hui Jie WAN Li Ya WANG Lian Xi CHEN hong ming zhang Hubei Research Institute of Chemistry,Wuhan 430074

Carboxymethylpachyman(Ⅰ)was formed by carboxymethylation of β-*** antitumour activity of carboxymethylpachyman(Ⅰ)against S_(180)、EAC、 MA、U_(14)was *** structure of carboxymethylpachyman(Ⅰ)was proved by IR ^(13)... 详细信息

关键词： CARBOXYMETHYLPACHYMAN A NEW WATER SOLUBLE POLYSACCHARIDE WITH MARKED ANTITUMOUR ACTIVITY CMP

Investigation of bubbles escape behavior from low basicity mold flux for high-Mn high-Al steels using 3D X-ray microscope

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International Journal of Minerals,Metallurgy and Materials 2025年第1期32卷 102-110页

作者： Qiang Liu Xiang Li Shen Du ming Gao Yanbin Yin Jiongming zhang State Key Laboratory of Advanced Metallurgy University of Science and Technology BeijingBeijing 100083China

During the continuous casting process of high-Mn high-Al steels,various types of gases such as Ar need to escape through the top of the *** which,the behavior of bubbles traversing the liquid slag serves as a restrictive link,closely associated with viscosity and the thickness of liquid *** contrast to two-dimensional surface observation,three-dimensional(3D)analysis method can offer a more intuitive,accurate,and comprehensive ***,this study employs a 3D X-ray microscope(3D-XRM)to obtained spatial distribution and 3D morphological characteristics of residual bubbles in mold flux under different basicity of liquid slag,different temperatures,and different holding *** results indicate that as basicity of slag increases from 0.52 to 1.03,temperature increases from 1423 to 1573 K,the viscosity of slag decreases,the floating rate of bubbles *** addition,when holding time increases from 10 to 30 s,the bubbles floating distance increases,and the volume fraction and average equivalent sphere diameter of the bubbles solidified in the mold flux gradually *** one word,increasing the basicity,temperature,and holding time leading to an increase in the removal rate of bubbles especially for the *** findings of bubbles escape behavior provide valuable insights into optimizing low basicity mold flux for high-Mn high-Al steels.

关键词： mold flux low basicity bubbles three-dimensional X-ray microscope viscosity