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体外预应力 2

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二氧化碳减排 1

内外因耦合 1

内模动态 1

内禀尺度 1

几何非线性 1

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分布式博弈策略；无人机；分布式模型预测控制；基于Levy飞行的鸽群优化算法；非奇异快速终端滑模观测器；避障策略 1

制度驱动路径依赖 1

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半导体激光器，光泵浦垂直外腔面发射激光器，纳米激光器，拓扑绝缘体激光器 1

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Approach and potential of replacing oil and natural gas with coal in China

Junjie LI, Yajun TIAN, Xiaohui YAN, Jingdong YANG, Yonggang WANG, Wenqiang XU, Kechang XIE

《能源前沿（英文）》 2020年 第14卷 第2期   页码 419-431 doi: 10.1007/s11708-020-0802-0

摘要： China’s fossil energy is characterized by an abundance of coal and a relative lack of oil and natural gas. Developing a strategy in which coal can replace oil and natural gas is, therefore, a necessary and practical approach to easing the excessive external dependence on oil and natural gas. Based on the perspective of energy security, this paper proposes a technical framework for defining the substitution of oil and natural gas with coal in China. In this framework, three substitution classifications and 11 industrialized technical routes are reviewed. Then, three scenarios (namely, the cautious scenario, baseline scenario, and positive scenario) are developed to estimate the potential of this strategy for 2020 and 2030. The results indicate that oil and natural gas replaced by coal will reach 67 to 81 Mt and 8.7 to 14.3 Gm in 2020 and reach 93 to 138 Mt and 32.3 to 47.3 Gm in 2030, respectively. By implementing this strategy, China’s external dependence on oil, natural gas, and primary energy is expected to be curbed at approximately 70%, 40%, and 20% by 2030, respectively. This paper also demonstrates how coal, as a substitute for oil and natural gas, can contribute to carbon and pollution reduction and economic cost savings. It suggests a new direction for the development of the global coal industry and provides a crucial reference for energy transformation in China and other countries with similar energy situations.

关键词： coal replacing oil and natural gas     energy security     external dependence     energy strategy     China    

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中国公司治理的路径依赖——理论与实证分析

邴红艳

《中国工程科学》 2004年 第6卷 第2期   页码 82-87

摘要：

文章在简要回顾路径依赖理论的基础上，运用公司治理路径依赖模型：结构驱动路径依赖和制度驱动的路径依赖模型，揭示了公司治理演进过程中路径依赖的作用机理，并针对中国公司治理演进过程中的路径依赖进行了实证分析。

关键词： 中国公司治理     路径依赖     结构驱动路径依赖     制度驱动路径依赖    

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Experimental study on the temperature dependence of ultraviolet absorption cross-sections of sulfur dioxide

ZHANG Shiliang, ZHOU Jie, CHEN Xiaohu

《能源前沿（英文）》 2008年 第2卷 第2期   页码 183-186 doi: 10.1007/s11708-008-0025-2

摘要： The photoabsorption cross-sections of sulfur dioxide were measured in the spectral regions of 200–230 nm and 275–315 nm at 298–415 K, using a grating monochromator with a resolution of 0.2 nm. The discrete absorption cross-section is directly correlated with the number of quantum excited from the base state. The absorption cross-sections at the peaks of discrete bands decreased linearly with the increase of temperature, which corresponded to the decrease in the population of vibrational and rotational transitions from the base level to higher excitation levels. The absorption cross-section peaks decreased linearly when the temperature increased from 298 to 415 K, with relative drops of 74.0% and 75.8% at 200–230 nm and 275–315 nm, respectively. Another distinctive feature of sulfur dioxide absorption spectra in the above two spectral regions was the quasiperiodic structure of the absorption peaks, whose equal wavelength intervals were 1.53 nm and 1.95 nm, respectively. Red and blue shifts were not found at the absorption peak positions.
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Tank-dependence of the functionality and network differentiation of activated sludge community in a full-scale

《环境科学与工程前沿（英文）》 2023年 第17卷 第3期 doi: 10.1007/s11783-023-1636-x

摘要：

● Environmental parameters affected functional bacteria and network associations.

关键词： Activated sludge     Bacterial community     Tank-dependence     Network association     Functional bacteria    

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building information modeling (BIM) implementation on design and construction performance: a resource dependence

Dongping CAO, Heng LI, Guangbin WANG

《工程管理前沿（英文）》 2017年 第4卷 第1期   页码 20-34 doi: 10.15302/J-FEM-2017010

摘要： Drawing on resource dependence theory, this paper develops and empirically tests a model for understanding how the implementation of building information modeling (BIM) in construction projects impacts the performance of different project participating organizations through improving their interorganizational collaboration capabilities. Based on two sets of survey data collected from designers and general contractors in BIM-based construction projects in China, the results from partial least squares analysis and bootstrapping mediation test provide clear evidence that BIM-enabled capabilities of information sharing and collaborative decision-making as a whole play a significant role in determining BIM-enabled efficiency and effectiveness benefits for both designers and general contractors. The results further reveal that designers and general contractors benefit from project BIM implementation activities significantly non-equivalently, and that this non-equivalence closely relates to the different roles played by designers and general contractors in BIM-enabled interorganizational resource exchange processes. The findings validate the resource dependence theory perspective of BIM as a boundary spanning tool to manage interorganizational resource dependence in construction projects, and contribute to deepened understandings of how and why project participating organizations benefit differently from the implementation of interorganizational information technologies like BIM.

关键词： building information modeling     interorganizational collaboration     construction project performance     resource dependence theory     partial least squares modeling    

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Time- and temperature-dependence of compressive and tensile behaviors of polypropylene fiber-reinforced

《结构与土木工程前沿（英文）》 2021年 第15卷 第4期   页码 1025-1037 doi: 10.1007/s11709-021-0741-9

摘要： The understanding of compressive and tensile behaviors of polypropylene fiber-reinforced cemented paste backfill (FR-CPB) play crucial roles in the successful implementation of reinforcement technique in underground mine backfilling operations. However, very limited studies have been performed to gain insight into the evolution of compressive and tensile behaviors and associated mechanical properties of FR-CPB under various curing temperatures from early to advanced ages. Thus, this study aims to investigate the time (7, 28, and 90 d)- and temperature (20°C, 35°C, and 45°C)-dependence of constitutive behavior and mechanical properties of FR-CPB. The obtained results show that pre- and post-failure behaviors of FR-CPB demonstrate strongly curing temperature-dependence from early to advanced ages. Moreover, the pseudo-hardening behavior is sensitive to curing temperature, especially at early ages. Furthermore, the mechanical properties including elastic modulus, material stiffness, strengths, brittleness, cohesion, and internal friction angle of FR-CPB show increasing trends with curing temperature as curing time elapses. Additionally, a predictive model is developed to capture the strong correlation between compressive and tensile strength of FR-CPB. The findings of this study will contribute to the successful implementation of FR-CPB technology.

关键词： cemented paste backfill     fiber reinforcement     constitutive behavior     temperature     tailings    

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Phase separation time/temperature dependence of thermoplastics-modified thermosetting systems

ZHANG Xiujuan, XU Yuanze, YI Xiaosu

《化学科学与工程前沿（英文）》 2008年 第2卷 第3期   页码 276-285 doi: 10.1007/s11705-008-0057-5

摘要： The cure-induced phase separation processes of various thermoplastics(TP)-modified thermosetting systems which show upper critical solution temperature (UCST) or lower critical solution temperature (LCST) were studied with emphasis on the temperature dependency of the phase separation time and its potential application in the cure time-temperature processing window. We found that the phase separation time/temperature relationship follows the simple Arrhenius equation. The cure-induced phase separation activation energy (ps) generated from the linear fitting of the Arrhenius equation is irrelevant to the detection means of phase separation time. We also found that (ps) is insensitive to TP content, TP molecular weight and curing rate, but it changes with the cure reaction kinetics and the chemical environment of the systems. With the established phase separation time-temperature dependence relation, we can easily establish the whole cure time-temperature transformation (TTT) diagram with morphology information which is a useful map for the TP/TS composites processing industry.

关键词： separation time-temperature     temperature dependency     cure-induced     separation activation     temperature    

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nitride enabled benzimidazoles production from furyl/aryl bio-alcohols and -nitroanilines without an external

《化学科学与工程前沿（英文）》 2023年 第17卷 第1期   页码 68-81 doi: 10.1007/s11705-022-2174-y

摘要： Benzimidazole derivatives have wide-spectrum biological activities and pharmacological effects, but remain challenging to be produced from biomass feedstocks. Here, we report a green hydrogen transfer strategy for the efficient one-pot production of benzimidazoles from a wide range of bio-alcohols and o-nitroanilines enabled by cobalt nitride species on hierarchically porous and recyclable nitrogen-doped carbon catalysts (Co/CNx-T, T denotes the pyrolysis temperature) without using an external hydrogen source and base additive. Among the tested catalysts, Co/CNx-700 exhibited superior catalytic performance, furnishing 2-substituted benzimidazoles in 65%–92% yields. Detailed mechanistic studies manifest that the coordination between Co2+ and N with appropriate electronic state on the porous nitrogen-doped carbon having structural defects, as well as the remarkable synergetic effect of Co/N dual sites contribute to the pronounced activity of Co/CNx-700, while too high pyrolysis temperature may cause the breakage of the catalyst Co–N bond to lower down its activity. Also, it is revealed that the initial dehydrogenation of bio-alcohol and the subsequent cyclodehydrogenation are closely correlated with the hydrogenation of nitro groups. The catalytic hydrogen transfer-coupling protocol opens a new avenue for the synthesis of N-heterocyclic compounds from biomass.

关键词： biomass conversion     furanic compounds     benzimidazoles     hydrogen transfer     bifunctional catalysis    

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Unified solution of limit loads of thick wall cylinder subject to external pressure considering strain

CHEN Changfu, XIAO Shujun, YANG Yu

《结构与土木工程前沿（英文）》 2007年 第1卷 第3期   页码 329-333 doi: 10.1007/s11709-007-0043-x

摘要： Based on the unified strength theory [1], a unified strength criterion for strain softening materials, such as concrete or rock, was derived, and the elastic and plastic limit loads of a thick-walled cylinder made of these materials subject to external pressure were also given. In addition, the influence of some factors on the limit loads of such cylinders as the ratio of the external radius to internal radius,/, the coefficient , which reflects the effect of medium principal stress and the normal stress of the relevant surface on the material destroy degree, the ratio of tensile strength to compressed strength of the material, , and the damage variable
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monitoring of the strengthening construction of a segmental box girder bridge and field testing of external

Ali Fadhil NASER, Zonglin WANG

《结构与土木工程前沿（英文）》 2012年 第6卷 第3期   页码 308-320 doi: 10.1007/s11709-012-0140-3

摘要： Prestressed concrete segmental box girder bridges are composed of short concrete segments that are either precast or cast in situ and then joined together by longitudinally post-tensioning internal, external, or mixed tendons. The objectives of this study are to monitor the construction process of the external prestressing tendons to strengthen the bridge structure and perform a field load test to measure the strain and the deflection of the anchorage devices of the external prestressing tendons to determine the state of these devices after tension forces are applied. The monitoring process of the external prestressing tendons construction includes inspecting the cracks in the diaphragm anchorage and the deviation block devices before the tension forces are applied to the external tendons; measuring the deformation of the steel deviation cross beam during the tension process; measuring the deformation of the box girder after different levels of tension forces are applied; measuring the elongation of the external tendons in each level of the tension; and measuring the natural frequency of the external tendons after the tension process is complete. The results of the monitoring process show that the measured values of the deformation, the elongation, and the natural frequency meet the requirements. Therefore, there is no damage during the construction and the tensioning of the external prestressing tendons. A field load test is performed to the anchorage beam, the steel deviation block devices, and the steel deviation cross beam. The field load test results of the anchorage devices show that the values of the strains, the stresses, and the deflection are less than the respective allowable limit values in the requirements. Therefore, the anchorage devices have sufficient strength, and the working state is good after the tension forces are applied to the external prestressing tendons.

关键词： prestressed concrete     box girder     monitoring     external tendons     strain     deflection    

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Shear behavior of ultra-high-performance concrete beams prestressed with external carbon fiber-reinforced

《结构与土木工程前沿（英文）》 2021年 第15卷 第6期   页码 1426-1440 doi: 10.1007/s11709-021-0783-z

摘要： The ultra-high-performance concrete (UHPC) and fiber-reinforced polymer (FRP) are well-accepted high-performance materials in the field of civil engineering. The combination of these advanced materials could contribute to improvement of structural performance and corrosion resistance. Unfortunately, only limited studies are available for shear behavior of UHPC beams reinforced with FRP bars, and few suggestions exist for prediction methods for shear capacity. This paper presents an experimental investigation on the shear behavior of UHPC beams reinforced with glass FRP (GFRP) and prestressed with external carbon FRP (CFRP) tendons. The failure mode of all specimens with various shear span to depth ratios from 1.7 to 4.5 was diagonal tension failure. The shear span to depth ratio had a significant influence on the shear capacity, and the effective prestressing stress affected the crack propagation. The experimental results were then applied to evaluate the equations given in different codes/recommendations for FRP-reinforced concrete structures or UHPC structures. The comparison results indicate that NF P 18-710 and JSCE CES82 could appropriately estimate shear capacity of the slender specimens with a shear span to depth ratio of 4.5. Further, a new shear design equation was proposed to take into account the effect of the shear span to depth ratio and the steel fiber content on shear capacity.

关键词： beam     external prestressing     ultra-high-performance concrete     fiber-reinforced polymers     shear behavior     design equation    

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Ductile extension of 3-D external circumferential cracks in pipe structures

Wuchao YANG, Xudong QIAN

《结构与土木工程前沿（英文）》 2011年 第5卷 第3期   页码 294-303 doi: 10.1007/s11709-011-0115-9

摘要： This study investigates the ductile fracture resistance of 3-D external circumferential cracks in the wall of a steel pipe under remote tension, using a damage-mechanism model originally proposed by Gurson and Tvergaard. The ductile crack extension utilizes an element extinction technique implemented in the computational cell framework. The key parameter for the computational cell method, i.e., the initial porosity ratio , is calibrated using both the fracture resistance and the load-deformation responses obtained from fracture tests of multiple single-edge bend [SE(B)] specimens made of high-strength steel, HY80, which has a yield strength of 630 MPa. The fracture resistance along the 3-D semi-elliptical crack front is computed from the calibrated cell model. Based on the similarity concept in the near-tip stress-strain fields, this study demonstrates that an equivalent 2-D axi-symmetric model provides conservative estimations of the fracture resistance for 3-D circumferential cracks in pipes.

关键词： ductile fracture     computational cell method     G-T model     J-R curve    

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Mesh relationship modeling and dynamic characteristic analysis of external spur gears with gear wear

《机械工程前沿（英文）》 2022年 第17卷 第1期   页码 9-9 doi: 10.1007/s11465-021-0665-z

摘要： Gear wear is one of the most common gear failures, which changes the mesh relationship of normal gear. A new mesh relationship caused by gear wear affects meshing excitations, such as mesh stiffness and transmission error, and further increases vibration and noise level. This paper aims to establish the model of mesh relationship and reveal the vibration characteristics of external spur gears with gear wear. A geometric model for a new mesh relationship with gear wear is proposed, which is utilized to evaluate the influence of gear wear on mesh stiffness and unloaded static transmission error (USTE). Based on the mesh stiffness and USTE considering gear wear, a gear dynamic model is established, and the vibration characteristics of gear wear are numerically studied. Comparison with the experimental results verifies the proposed dynamic model based on the new mesh relationship. The numerical and experimental results indicate that gear wear does not change the structure of the spectrum, but it alters the amplitude of the meshing frequencies and their sidebands. Several condition indicators, such as root-mean-square, kurtosis, and first-order meshing frequency amplitude, can be regarded as important bases for judging gear wear state.

关键词： gear wear     mesh relationship     mesh stiffness     transmission error     vibration characteristics    

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单向离合器外环应力计算的有限元方法研究

罗一新,吴波

《中国工程科学》 2004年 第6卷 第9期   页码 56-59

摘要：

单向离合器是一种常见的机械传动部件，其外环应力计算尚无理想的方法。文章以五滚柱式单向离合器为研究对象，根据外环的特点，采用有限元分析方法，分析了影响其计算精度的各种因素，计算出其外环的应力，并且将计算结果与曲梁计算法进行了比较。研究表明，有限元分析方法对于外环类零件的应力计算确是一种理想的方法。

关键词： 离合器     外环     应力     有限元    

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patients with advanced malignant obstructive jaundice treated by percutaneous transhepatic biliary external

ZHU Lidong, CHEN Xiaoping

《医学前沿（英文）》 2007年 第1卷 第4期   页码 364-368 doi: 10.1007/s11684-007-0070-y

摘要： The aim of this article was to study the influence of immunity function of advanced malignant obstructive jaundice (MOJ) treated by percutaneous transhepatic biliary external and internal drainage. Ninety-six cases of MOJ were divided into two groups according to the different ways of biliary drainage. Fifty-two external drainage tubes were placed in 41 cases of percutaneous transhepatic biliary external drainage group and 66 metal stents were placed in 55 cases of percutaneous transhepatic biliary internal drainage group. Liver function, serum TNF- and cellular function were examined one day before operation and one week after operation and liver function was re-examined two weeks after operation, in order to observe the change and analyze the asso ciation among them and compare with the control group. All patients conditions were improved after operation. In the percutaneous transhepatic biliary external and internal drainage groups, the total level of bilirubin decreased from (343.54±105.56) μ mol/L and (321.19±110.50) μ mol/L to (290.56±103.46) μ mol/L and (283.72±104.95) μ mol/L after operation respectively, which were significantly lower than pre-operation (<0.05), but there was no significant difference between the two groups (>0.05). Serum alanine aminotransferase (ALT) of all patients one week after operation was significantly lower than that before operation. TNF- in percutaneous transhepatic biliary external and internal groups decreased from (108.58±19.95) pg/mL, (109.98±16.24) pg/mL of pre-operation to (104.32±19.59) pg/mL, (83.92±13.43) pg/mL of post-operation respectively, there was notable improvement (<0.01) in internal drainage group after operation. Patients serum CD4, CD3 and CD4/CD8 were notably increased, but CD8 was notably decreased (<0.05). There was no difference in external drainage group (>0.05). There was a significant difference between the two groups. Serum TNF- and ALT had positive correlation. Percutaneous transhepatic biliary internal or external drainage was an effective and important method to treat MOJ. Patients immune function was weak when they suffered MOJ, but body s cellular immune function can be notably improved after internal biliary drainage.
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标题 作者 时间 类型 操作

Approach and potential of replacing oil and natural gas with coal in China

Junjie LI, Yajun TIAN, Xiaohui YAN, Jingdong YANG, Yonggang WANG, Wenqiang XU, Kechang XIE

期刊论文

中国公司治理的路径依赖——理论与实证分析

邴红艳

期刊论文

Experimental study on the temperature dependence of ultraviolet absorption cross-sections of sulfur dioxide

ZHANG Shiliang, ZHOU Jie, CHEN Xiaohu

期刊论文

Tank-dependence of the functionality and network differentiation of activated sludge community in a full-scale

期刊论文

building information modeling (BIM) implementation on design and construction performance: a resource dependence

Dongping CAO, Heng LI, Guangbin WANG

期刊论文

Time- and temperature-dependence of compressive and tensile behaviors of polypropylene fiber-reinforced

期刊论文

Phase separation time/temperature dependence of thermoplastics-modified thermosetting systems

ZHANG Xiujuan, XU Yuanze, YI Xiaosu

期刊论文

nitride enabled benzimidazoles production from furyl/aryl bio-alcohols and -nitroanilines without an external

期刊论文

Unified solution of limit loads of thick wall cylinder subject to external pressure considering strain

CHEN Changfu, XIAO Shujun, YANG Yu

期刊论文

monitoring of the strengthening construction of a segmental box girder bridge and field testing of external

Ali Fadhil NASER, Zonglin WANG

期刊论文

Shear behavior of ultra-high-performance concrete beams prestressed with external carbon fiber-reinforced

期刊论文

Ductile extension of 3-D external circumferential cracks in pipe structures

Wuchao YANG, Xudong QIAN

期刊论文

Mesh relationship modeling and dynamic characteristic analysis of external spur gears with gear wear

期刊论文

单向离合器外环应力计算的有限元方法研究

罗一新,吴波

期刊论文

patients with advanced malignant obstructive jaundice treated by percutaneous transhepatic biliary external

ZHU Lidong, CHEN Xiaoping

期刊论文