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合成橡胶 2

TRIP钢 1

WTO 1

ZN-1阻尼橡胶材料 1

一水硬铝石 1

二阶矩技术 1

优化设计 1

优化调度 1

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割胶制度 1

动力学 1

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劲性骨架混凝土拱桥 1

可持续性 1

可转换整体式自升模板体系 1

可靠性 1

合成化学 1

合成橡胶，热塑性弹性体，特种橡胶，发展战略 1

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Performance of a novel bent-up bars system not interacting with concrete

Aydin SHISHEGARAN, Mohammad Reza GHASEMI, Hesam VARAEE

《结构与土木工程前沿（英文）》 2019年 第13卷 第6期   页码 1301-1315 doi: 10.1007/s11709-019-0552-4

摘要： Increasing the bending and shear capacities of reinforced concrete members is an interesting issue in structural engineering. In recent years, many studies have been carried out to improve capacities of reinforced concrete members such as using post and pre-tensioning, Fiber Reinforced Polymer and other techniques. This paper proposes a novel and significant technique to increase the flexural capacity of simply supported reinforced concrete beams. The proposed method uses a new reinforcement bar system having bent-up bars, covered with rubber tubes. This technique will avoid interaction of bent-up bars with concrete. They are located in the zone where compressive and tensile forces act against one another. The compressive force in the upper point of the bent-up bars is exerted to the end point of these bars located under neutral axis. Moreover, the tensile stress is decreased in reinforcements located under the neutral axis. This will cause the Reinforced Concrete (RC) beam to endure extra loading before reaching yield stress. These factors may well be considered as reasons to increase bending capacity in the new system. The laboratory work together with finite element method analysis were carried out in this investigation. Furthermore, bending capacity, ductility, strength, and cracking zone were assessed for the new proposed system and compared with the conventional model. Both the FEM simulation and the experimental test results revealed that the proposed system has significant impact in increasing the load bearing capacity and the stiffness of the RC beams. In the present study, an equation is formulated to calculate bending capacity of a new reinforcement bar system beam.

关键词： bending capacity     rubber tube     stress transfer     bent-up bars     ductility     cracking    

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Evaluation of the compatibility between rubber and asphalt based on molecular dynamics simulation

Fucheng GUO, Jiupeng ZHANG, Jianzhong PEI, Weisi MA, Zhuang HU, Yongsheng GUAN

《结构与土木工程前沿（英文）》 2020年 第14卷 第2期   页码 435-445 doi: 10.1007/s11709-019-0603-x

摘要： Using of rubber asphalt can both promote the recycling of waste tires and improve the performance of asphalt pavement. However, the segregation of rubber asphalt caused by the poor storage stability always appears during its application. Storage stability of asphalt and rubber is related to the compatibility and also influenced by rubber content. In this study, molecular models of different rubbers and chemical fractions of asphalt were built to perform the molecular dynamics simulation. The solubility parameter and binding energy between rubber and asphalt were obtained to evaluate the compatibility between rubber and asphalt as well as the influence of rubber content on compatibility. Results show that all three kinds of rubber are commendably compatible with asphalt, where the compatibility between asphalt and cis-polybutadiene rubber (BR) is the best, followed by styrene-butadiene rubber (SBR), and natural rubber (NR) is the worst. The optimum rubber contents for BR asphalt, SBR asphalt, and NR asphalt were determined as 15%, 15%, and 20%, respectively. In addition, the upper limits of rubber contents were found as between 25% and 30%, between 20% and 25%, and between 25% and 30%, respectively.

关键词： rubber asphalt     compatibility     rubber content     molecular dynamics simulation    

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Parametric study on seismic performance of self-centering reinforced concrete column with bottom-placed rubber

《结构与土木工程前沿（英文）》   页码 1145-1162 doi: 10.1007/s11709-023-0945-2

摘要： To realize seismic-resilient reinforced concrete (RC) moment-resisting frame structures, a novel self-centering RC column with a rubber layer placed at the bottom (SRRC column) is proposed herein. For the column, the longitudinal reinforcement dissipates seismic energy, the rubber layer allows the rocking of the column, and the unbonded prestressed tendon enables self-centering capacity. A refined finite element model of the SRRC column is developed, the effectiveness of which is validated based on experimental results. Results show that the SRRC column exhibits stable energy dissipation capacity and no strength degradation; additionally, it can significantly reduce permanent residual deformation and mitigate damage to concrete. Extensive parametric studies pertaining to SRRC columns have been conducted to investigate the critical factors affecting their seismic performance.

关键词： seismic resilience     self-centering     rubber layer     flag-shaped hysteresis loop     parametric study    

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Using thermodynamic parameters to study self-healing and interface properties of crumb rubber modified

Dongliang HU, Jianzhong PEI, Rui LI, Jiupeng ZHANG, Yanshun JIA, Zepeng FAN

《结构与土木工程前沿（英文）》 2020年 第14卷 第1期   页码 109-122 doi: 10.1007/s11709-019-0579-6

摘要： The thermodynamic property of asphalt binder is changed by the addition of crumb rubber, which in turn influences the self-healing property as well as the cohesion and adhesion within the asphalt-aggregate system. This study investigated the self-healing and interface properties of crumb rubber modified asphalt (CRMA) using thermodynamic parameters based on the molecular simulation approach. The molecular models of CRMA were built with representative structures of the virgin asphalt and the crumb rubber. The aggregate was represented by SiO and Al O crystals. The self-healing capability was evaluated with the thermodynamic parameter wetting time, work of cohesion and diffusivity. The interface properties were evaluated by characterizing the adhesion capability, the debonding potential and the moisture susceptibility of the asphalt-aggregate interface. The self-healing capability of CRMA is found to decrease as the rubber content increases. The asphalt-Al O interface with higher rubber content has stronger adhesion and moisture stability. But the influence of crumb rubber on the interfacial properties of asphalt-SiO interface has no statistical significance. Comparing with the interfacial properties of the asphalt-SiO interface, the asphalt-Al O interface is found to have a stronger adhesion but a worse moisture susceptibility for its enormous thermodynamic potential for water to displace the asphalt binder.

关键词： crumb rubber modified asphalt     surface free energy     self-healing     interface properties     molecular dynamics simulation    

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溶液聚合合成橡胶节能技术和节能型橡胶的开发

曹湘洪,张爱民

《中国工程科学》 2001年 第3卷 第7期   页码 59-63

摘要：

总结了燕山石化溶液聚合合成橡胶节能技术和节能型橡胶的开发情况。通过改进催化体系，提高反应速度，提高反应器的生产能力，并在聚合反应器中采用带刮刀的搅拌器，同时改进聚合、凝聚、溶剂回收的部分工艺及设备，燕山石化顺丁橡胶的能耗不断下降，达到世界先进水平。溶液聚合合成橡胶凝聚过程热泵技术的工业化，使生产每吨胶可节约1MPa的低压蒸汽0.72t。橡胶溶液直接脱挥，聚丁二烯橡胶气相聚合工艺技术开发,溶聚丁苯橡胶（SSBR）、中乙烯基聚丁二烯橡胶、苯乙烯-异戊二烯-丁二烯橡胶（SIBR）、苯乙烯-丁二烯热塑性弹性体（SBS）等新型节能型合成橡胶的技术开发也在进行中，其中SSBR、SBS技术已经工业化。

关键词： 溶液聚合     合成橡胶     节能     节能型橡胶    

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Aging properties and aging mechanism of activated waste rubber powder modified asphalt binder based on

《结构与土木工程前沿（英文）》 2023年 第17卷 第4期   页码 625-636 doi: 10.1007/s11709-023-0938-1

摘要： The research and development of high-performance pavement materials has been intensified owing to the demand for long-life pavements. This study is performed to develop a novel pavement material using waste rubber powder, waste lubricating by-product (LBP), and asphalt. Subsequently, the aging properties and aging mechanism of activated waste rubber powder modified asphalt (ARMA) are investigated based on its rheological properties and micro-characterization. The rheological results show that, compared with waste rubber powder modified asphalt (RMA), ARMA offers a higher aging resistance and a longer fatigue life. A comparison and analysis of the rheological aging parameters of ARMA and RMA show that LBP activation diminishes the aging sensitivity of ARMA. The micro-characterization result shows that the aging of ARMA may be caused by the fact that LBP-activated waste rubber powder is more reactive and can form a dense colloidal structure with asphalt. Therefore, the evaporation loss of asphalt light components by heat and the damage to the colloidal structure by oxygen during the aging process are impeded, and the thermal-oxidative aging resistance of ARMA is improved.

关键词： rubber powder modified asphalt     aging     mechanism     rheological     characterization    

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Relationship between the number of tapping-induced secondary laticifer lines and rubber yield among

Yueyi CHEN,Xinsheng GAO,Xiaofei ZHANG,Weimin TIAN

《农业科学与工程前沿（英文）》 2016年 第3卷 第4期   页码 363-367 doi: 10.15302/J-FASE-2016122

摘要： The lack of suitable early selection parameters means that traditional rubber breeding for yield is time-consuming and inefficient. Laticifer is a tissue specific for natural rubber biosynthesis and storage in rubber tree. The number of the secondary laticifers in the trunk bark tissues is positively correlated with rubber yield in the matured rubber trees that are regularly tapped. In the present study, the rubber yield from 280 of 4–5 year-old virgin trees from 7 cross combinations was compared with the number of newly differentiated secondary laticifers caused by tapping. Results showed that the number of tapping-induced lines of secondary laticifers varied in different germplasm and was positively related to the rubber yield, indicating this could be used as a suitable parameter for early evaluation of yield potential of rubber trees.

关键词： Hevea brasiliensis     rubber yield breeding     early evaluation     tapping     secondary laticifer differentiation    

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Hysteretic behavior of cambered surface steel tube damper: Theoretical and experimental research

《结构与土木工程前沿（英文）》 2023年 第17卷 第4期   页码 606-624 doi: 10.1007/s11709-023-0925-6

摘要： A novel cambered surface steel tube damper (CSTD) with a cambered surface steel tube and two concave connecting plates is proposed herein. The steel tube is the main energy dissipation component and comprises a weakened segment in the middle, a transition segment, and an embedded segment. It is believed that during an earthquake, the middle weakened segment of the CSTD will be damaged, whereas the reliability of the end connection is ensured. Theoretical and experimental studies are conducted to verify the effectiveness of the proposed CSTD. Formulas for the initial stiffness and yield force of the CSTD are proposed. Subsequently, two CSTD specimens with different steel tube thicknesses are fabricated and tested under cyclic quasi-static loads. The result shows that the CSTD yields a stable hysteretic response and affords excellent energy dissipation. A parametric study is conducted to investigate the effects of the steel tube height, diameter, and thickness on the seismic performance of the CSTD. Compared with equal-stiffness design steel tube dampers, the CSTD exhibits better energy dissipation performance, more stable hysteretic response, and better uniformity in plastic deformation distributions.

关键词： cambered surface steel tube damper     energy dissipation capacity     finite element model     hysteretic performance     parametric study    

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Transversal tube pitch effects on local heat transfer characteristics of the flat tube bank fin mounted

Liangbi WANG, Zhimin LIN, Kangjie SUN, Yuanxin DONG, Song LIU, Yongheng ZHANG,

《能源前沿（英文）》 2010年 第4卷 第3期   页码 333-345 doi: 10.1007/s11708-009-0061-6

摘要： The tube bank fin is commonly used to increase the area of the heat transfer surface with a small heat transfer coefficient of a heat exchanger. If vortex generators (VGs) are punched on the fin surface, the heat transfer performance of the fin can be improved. This paper focused on the effect of transversal tube pitch on the local heat transfer performance of the three-row flat tube bank fin mounted with VGs. On the fin surface, constructing the flow channel but without mounted VGs, the transversal tube pitch was greater, and the span averaged Nusselt number downstream was larger because fewer interactions of vortices would be generated from different VGs located upstream. When the area goodness factor was used as the criteria on the condition of one tube unit of heat exchanger for commonly used fin materials and fin thickness, the transversal tube pitch has considerable effect on the heat transfer enhancement of VGs. Large transversal tube pitch is more sensitive to fin material than to fin thickness.

关键词： heat transfer enhancement     vortex generator     finned flat tube bank     heat exchanger    

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Study on the gas permeabilities in styrene-butadiene rubber by molecular dynamics simulation

Hailu LIU, Xuejia DING, Jun YI, Liqun ZHANG, Sizhu WU,

《化学科学与工程前沿（英文）》 2010年 第4卷 第3期   页码 257-262 doi: 10.1007/s11705-009-0270-x

摘要： In this research, molecular dynamics (MD)simulations were used to study the transport properties of small gas molecules in the butadiene-styrene copolymer(SBR). The condensed-phase optimized molecular potentials for atomistic simulation studies (COMPASS) force field was applied. The diffusion coefficients were obtained from MD (NVT ensemble) and the relationship between gas permeability; the chemical structure and free volume of butadiene-styrene copolymer were investigated. The results indicated that the diffusion coefficient of oxygen declined with increasing styrene content. The fraction of free volume (FFV) in butadiene-styrene copolymer was calculated. It was concluded that diffusion coefficient increased as the FFV increases, which is in accordance with the analysis of the small molecular hop through the free volume in polymer matrix. Subsequently, the glass transition temperatures of these copolymers were calculated by MD. The result showed that the glass transition temperature increased with increasing styrene content in polymer.

关键词： diffusion     atomistic simulation     permeability     chemical structure     relationship    

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合成橡胶化学及技术进展

武冠英

《中国工程科学》 1999年 第1卷 第3期   页码 79-85

摘要：

文章从合成橡胶的化学基础出发，叙述了合成橡胶工业二十世纪以来的过去、现状，并展望未来。着重讨论了合成化学基础及相应聚合工艺过程的进步这两方面的问题。指出合成橡胶化学基础中活性聚合、可控聚合，包括茂金属催化剂仍为近期的重点；气相聚合工艺将会得到较大的发展；高效聚合釜的研究仍是核心问题；环保问题应更受到重视。

关键词： 合成橡胶     合成化学     活性/控制聚合     气相聚合    

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The secondary laticifer differentiation in rubber tree is induced by trichostatin A, an inhibitor of

Shixin ZHANG,Shaohua WU,Weimin TIAN

《农业科学与工程前沿（英文）》 2016年 第3卷 第4期   页码 357-362 doi: 10.15302/J-FASE-2016125

摘要： The secondary laticifer, a specific tissue in the secondary phloem of rubber tree, is differentiated from the vascular cambia. The number of the secondary laticifer in the trunk bark of rubber tree is positively correlated with rubber yield. Although jasmonates have been demonstrated to be crucial in the regulation of secondary laticifer differentiation, the mechanism for the jasmonate-induced secondary laticifer differentiation remains to be elucidated. By using an experimental morphological technique, the present study revealed that trichostatin A (TSA), an inhibitor of histone deacetylation, could induce the secondary laticifer differentiation in a concentration-dependent manner. The results suggest that histone acetylation is essential for the secondary laticifer differentiation in rubber tree.

关键词： Hevea brasiliensis     histone acetylation     laticifer differentiation     trichostatin     vascular cambia    

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Energy distribution between liquid hydrogen and liquid oxygen temperatures in a Stirling/pulse tube refrigerator

《能源前沿（英文）》 2023年 第17卷 第4期   页码 516-526 doi: 10.1007/s11708-022-0844-6

摘要： A two-stage gas-coupled Stirling/pulse tube refrigerator (SPR), whose first and second stages respectively involve Stirling and pulse tube refrigeration cycles, is a very promising spaceborne refrigerator. The SPR has many advantages, such as a compact structure, high reliability, and high performance, and is expected to become an essential refrigerator for space applications. In research regarding gas-coupled regenerative refrigerator, the energy flow distribution between the two stages, and optimal phase difference between the pressure wave and volume flow, are two critical parameters that could widely influence refrigerator performance. The effects of displacer displacement on the pressure wave, phase difference, acoustic power distribution, and inter-stage cooling capacity shift of the SPR have been investigated experimentally. Notably, to obtain the maximum first-stage cooling capacity, an inflection point in displacement exists. When the displacer displacement is larger than the inflection point, the cooling capacity could be distributed between the first and second stages. In the present study, an SPR was designed and manufactured to work between the liquid hydrogen and liquid oxygen temperatures, which can be used to cool small-scale zero boil-off systems and space detectors. Under appropriate displacer displacement, the SPR can reach a no-load cooling temperature of 15.4 K and obtain 2.6 W cooling capacity at 70 K plus 0.1 W cooling capacity at 20 K with 160 W compressor input electric power.

关键词： Stirling/pulse tube refrigerator     displacer displacement     space application     phase shift     energy distribution    

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Genetic evidence in planar cell polarity signaling pathway in human neural tube defects

null

《医学前沿（英文）》 2014年 第8卷 第1期   页码 68-78 doi: 10.1007/s11684-014-0308-4

摘要：

Neural tube defects (NTDs) are a group of birth anomalies having a profound physical, emotional, and financial effects on families and communities. Their etiology is complex, involving environmental and genetic factors that interact to modulate the incidence and severity of the developing phenotype. The planar cell polarity (PCP) pathway controls the process of convergent extension (CE) during gastrulation and neural tube closure and has been implicated in the pathogenesis of NTDs in animal models and human cohorts. This review summarizes the cumulative results of recent studies on PCP signaling pathway and human NTDs. These results demonstrate that PCP gene alterations contribute to the etiology of human NTDs.

关键词： planar cell polarity     neural tube defects     rare mutations    

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我国天然橡胶业面临的挑战和发展战略

黄宗道

《中国工程科学》 2001年 第3卷 第2期   页码 28-32

摘要：

自1949年中华人民共和国建立以来，中国的天然橡胶获得了迅速的发展。到1998年橡胶种植面积达到60×104hm2，是1949前的215倍；产量达到45×104t，是以前的2 250倍。致使中国成为世界天然橡胶的主要产胶国之一，植胶面积为世界第四位，产量为第五位。

我国加人世界贸易组织后，低价的天然橡胶将很快进入我国市场，冲击我国的天然橡胶业，我们必须清醒 地了解我们现在所处的地位和情况及时采取对策。文中提出了我国天然橡胶今后的发展战略。

 

关键词： 天然橡胶     WTO     割胶制度    

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标题 作者 时间 类型 操作

Performance of a novel bent-up bars system not interacting with concrete

Aydin SHISHEGARAN, Mohammad Reza GHASEMI, Hesam VARAEE

期刊论文

Evaluation of the compatibility between rubber and asphalt based on molecular dynamics simulation

Fucheng GUO, Jiupeng ZHANG, Jianzhong PEI, Weisi MA, Zhuang HU, Yongsheng GUAN

期刊论文

Parametric study on seismic performance of self-centering reinforced concrete column with bottom-placed rubber

期刊论文

Using thermodynamic parameters to study self-healing and interface properties of crumb rubber modified

Dongliang HU, Jianzhong PEI, Rui LI, Jiupeng ZHANG, Yanshun JIA, Zepeng FAN

期刊论文

溶液聚合合成橡胶节能技术和节能型橡胶的开发

曹湘洪,张爱民

期刊论文

Aging properties and aging mechanism of activated waste rubber powder modified asphalt binder based on

期刊论文

Relationship between the number of tapping-induced secondary laticifer lines and rubber yield among

Yueyi CHEN,Xinsheng GAO,Xiaofei ZHANG,Weimin TIAN

期刊论文

Hysteretic behavior of cambered surface steel tube damper: Theoretical and experimental research

期刊论文

Transversal tube pitch effects on local heat transfer characteristics of the flat tube bank fin mounted

Liangbi WANG, Zhimin LIN, Kangjie SUN, Yuanxin DONG, Song LIU, Yongheng ZHANG,

期刊论文

Study on the gas permeabilities in styrene-butadiene rubber by molecular dynamics simulation

Hailu LIU, Xuejia DING, Jun YI, Liqun ZHANG, Sizhu WU,

期刊论文

合成橡胶化学及技术进展

武冠英

期刊论文

The secondary laticifer differentiation in rubber tree is induced by trichostatin A, an inhibitor of

Shixin ZHANG,Shaohua WU,Weimin TIAN

期刊论文

Energy distribution between liquid hydrogen and liquid oxygen temperatures in a Stirling/pulse tube refrigerator

期刊论文

Genetic evidence in planar cell polarity signaling pathway in human neural tube defects

null

期刊论文

我国天然橡胶业面临的挑战和发展战略

黄宗道

期刊论文