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期刊论文 9

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CBC－MAC模式 1

CCM模式 1

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体外预应力 1

凸块锚固区 1

悬臂效应 1

木材 1

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human bioaccessibility of trace contaminants in size-fractionated red mud, derived precipitates and geopolymericblocks

Chunfeng Wang, Yanchen Zhu, Dan Yao, Guanfei Chen, Lianjun Wang

《环境科学与工程前沿（英文）》 2017年 第11卷 第6期 doi: 10.1007/s11783-017-0956-0

摘要： The objective of this study was to provide insight into human exposure to trace contaminants bearing red mud, derived precipitates and geopolymeric blocks due to inhalation contact and/or hand-to-mouth ingestion. The in vitro bioaccessibility behavior of trace contaminants was investigated with the PBET (physiologically based extraction test), ALF (artificial lysosomal fluid) and MGS (modified Gamble’ solution) methods. The results showed that total contents of trace contaminants and operation parameters, such as pH and chelating properties of simulated gastrointestinal phases (PBET), played a joint role in controlling the bioaccessibility efficacy for size-fractionated red mud particles. As for airborne particles (<38 µm size fractions), trace contaminants concentrations extracted by MGS was significantly higher than those by ALF. Additionally, higher bioaccessibility (PBET) values of Cu, Pb, Zn, As, V and U were obtained from red mud derived precipitates compared with those of red mud itself. Even though short-term and long-term leaching values of trace contaminants were relatively lower in the prepared geopolymeric blocks, the health risk could be significantly higher due to the more pronounced bioaccessibility characteristics.

关键词： Bioaccessibility     Trace contaminants     Red mud     Precipitates     Geopolymeric blocks.    

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A continuous/discontinuous deformation analysis (CDDA) method based on deformable blocks for fracture

Yongchang CAI, Hehua ZHU, Xiaoying ZHUANG

《结构与土木工程前沿（英文）》 2013年 第7卷 第4期   页码 369-378 doi: 10.1007/s11709-013-0222-x

摘要： In the framework of finite element meshes, a novel continuous/discontinuous deformation analysis (CDDA) method is proposed in this paper for modeling of crack problems. In the present CDDA, simple polynomial interpolations are defined at the deformable block elements, and a link element is employed to connect the adjacent block elements. The CDDA is particularly suitable for modeling the fracture propagation because the switch from continuous deformation analysis to discontinuous deformation analysis is natural and convenient without additional procedures. The SIFs (stress intensity factors) for various types of cracks, such as kinked cracks or curved cracks, can be easily computed in the CDDA by using the virtual crack extension technique (VCET). Both the formulation and implementation of the VCET in CDDA are simple and straightforward. Numerical examples indicate that the present CDDA can obtain high accuracy in SIF results with simple polynomial interpolations and insensitive to mesh sizes, and can automatically simulate the crack propagation without degrading accuracy.

关键词： fracture     crack     propagation     deformable block     continuous/discontinuous deformation analysis (CDDA)    

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Solution properties and self-association of multi-blocks like copolymer P(AM/AA) prepared by template

ZHANG Yuxi, WU Feipeng, LI Miaozhen, WANG Erjian

《化学科学与工程前沿（英文）》 2007年 第1卷 第1期   页码 68-71 doi: 10.1007/s11705-007-0014-8

摘要： The association and properties of multi-block like copolymers (TP) of acrylamide (AM) and acrylic acid (AA) prepared by template copolymerization in aqueous solution were studied. The results showed that the copolymers of this type exhibited a significant structure effect compared with that of similar random copolymers (CP) obtained by copolymerization in the absence of template. Decreasing the value of pH or adding Ca ion to the copolymer solution will make phase separation occur. The TEM images demonstrated that the phase separation caused by Ca ion was due to the formation of extensively intermolecular cross-linking. With the increase of the pH value of copolymer solution, the changes of the solution viscosity was similar with that of homopolyacrylic acid, which originally increased and then decreased. But the increase range of template copolymer was higher than that of homopolyacrylic acid. TEM images indicated that at the maximal viscosity the copolymer obtained in the presence of template formed coiled aggregates.

关键词： aqueous solution     homopolyacrylic     copolymer solution     significant structure     presence    

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Strengthening Project Management to Attain Overseas Blocks with High Potential for Exploration

Shu-lin Zhang

《工程管理前沿（英文）》 2016年 第3卷 第4期   页码 331-337 doi: 10.15302/J-FEM-2016058

摘要： New overseas venture evaluation is key for oversea exploration of Chinese oil companies, whose credibility directly determine the degree of success of exploration for overseas blocks. The uniqueness of new overseas venture evaluation in short assessing cycle and limited data make project management vital. Project management includes human resource allocation, quality control and effective communication. In China National Offshore Oilfield Corporation (CNOOC), the new overseas venture evaluation system has been established. This system includes quality control system and assurance for new overseas venture evaluation, geological evaluation norms for overseas oil & gas exploration, regulations for new overseas venture evaluation and seismic interpretation methodology and procedure for new overseas venture evaluation. Directed by the new overseas venture evaluation system, three-level quality control and management of data-room visit are strictly reinforced, which guarantees the efficiency and quality of new overseas venture evaluation. As a result the new overseas venture evaluation boosts the development of young explorationists and leads to breakthroughs in exploring potential target areas of CNOOC and in the discovery of giant oil and gas fields, which underpins the development of overseas business in CNOOC.

关键词： new overseas venture evaluation     exploration     project management     quality management     assessing system    

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Molecular dynamics study of water diffusion in an amphiphilic block copolymer with large difference in the blocks

Yang Zhou, Phillip Choi

《化学科学与工程前沿（英文）》 2017年 第11卷 第3期   页码 440-447 doi: 10.1007/s11705-017-1626-2

摘要： Isothermal-isobaric molecular dynamics simulation was used to study the diffusion mechanism of water in polyurethane- -poly( -isopropyl acrylamide) (PU- -PNIPAm) with a hydrophobic PU/hydrophilic PNIPAm mass ratio of 1.4 to 1 at 298 K and 450 K. Here, the experimental glass transition temperature ( ) of PU is 243 K while that of PNIPAm is 383 K. Different amounts of water up to 15 wt-% were added to PU- -PNIPAm. We were able to reproduce the specific volumes and glass transition temperatures (250 K and 390 K) of PU- -PNIPAm. The computed self-diffusion coefficient of water increased exponentially with increasing water concentration at both temperatures (i.e., following the free volume model of Fujita). It suggested that water diffusion in PU- -PNIPAm depends only on its fractional free volume despite the free volume inhomogeneity. It is noted that at 298 K, PU is rubbery while PNIPAm is glassy. Regardless of temperature, radial distribution functions showed that water formed clusters with sizes in the range of 0.2–0.4 nm in PU- -PNIPAm. At low water concentrations, more clusters were found in the PU domain but at high water concentrations, more in the PNIPAm domain. It is believed that water molecules diffuse as clusters rather than as individual molecules.

关键词： molecular dynamics simulation     amphiphilic block copolymer     free volume     water diffusivity     fujita model    

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Mechanisms of connective tissue formation and blocks of mitogen activated protein kinase

Irina A SHURYGINA, Michael G SHURYGIN, Nataliya I AYUSHINOVA, Galina B GRANINA, Nikolay V ZELENIN

《化学科学与工程前沿（英文）》 2012年 第6卷 第2期   页码 232-237 doi: 10.1007/s11705-012-1286-1

摘要： Ninety male Wistar rats were selected under the “Guide for the Care and Use of Laboratory Animals” for skin-muscle wound models. Three groups of animals were examined respectively for inoculation of inhibitor of p38 MAPK (mitogen activated protein kinase) SB 203580 and JNK inhibitor SP 600125, and a control. Light microscopy, immunohistochemistry, and tensometry revealed that the inhibition of p38 or JNK cascades have modified the formation of the connective tissue scar. The degree of connective tissue growth in the area of surgical wound had been significantly reduced by the end of observation (30 d) as the SB 203580 was applied (% volume of collagen 43.60 (41.05 – 60.15) 73.54 (66.87 – 78.01) in control, = 0.002). Conversely, when we have applied the JNK blocker, the density of collagen in scar tissue increased (78.14 (72.77 – 81.14), = 0.022 control). SB203580 inhibits the expression of p38, c-Jun and c-Fos. When we have used the JNK blocker, the expression of c-Fos and c-Jun decreased, but the expression of p38 increased. This determines the high functional activity of fibroblasts after using SP 600125. Obtained results show the importance of studying regulators of cell differentiation as potential drugs, which significantly affect the outcome of the pathological processes.

关键词： connective tissue     mitogen activated protein kinase (MAPK)     p38     JNK    

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木块在小尺寸轰燃实验中的点燃及预测模型

季经纬,宋虎,杨立中,范维澄

《中国工程科学》 2003年 第5卷 第7期   页码 62-66

摘要：

利用小尺寸轰燃实验台对松木和杉木的点燃性能进行了研究。该实验台能够提供接近实际火灾的燃烧环境，实验具有较好的可重复性。在锥形量热计实验的基础上提出了一种新的材料热辐射引燃判据。采用实验测得的轰燃实验台上层热烟气温度的平均值，结合热辐射引燃判据计算了木材在轰燃实验台中的点燃情况。

关键词： 轰燃     木材     点燃    

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体外预应力凸块锚固区配筋设计研究

洪浩,童育强,贺志启,刘钊

《中国工程科学》 2013年 第15卷 第8期   页码 95-98

摘要：

混凝土凸块锚固区是体外预应力的一种常见锚固形式，目前尚没有成熟的设计方法。本文通过有限元数值分析，揭示了产生局部拉应力集中的3种作用效应；在此基础上，提出了这3种局部作用效应合拉力的解析计算公式，作为凸块锚固区定量化配筋设计的依据。通过南京长江第四大桥引桥凸块锚固区的设计实践，表明该方法具有良好的实用性。

关键词： 凸块锚固区     体外预应力     配筋设计     锚下劈裂     悬臂效应     锚后牵拉    

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基于双重分组和密钥计数的并行认证模式

黄玉划,胡爱群,宋宇波

《中国工程科学》 2004年 第6卷 第7期   页码 70-74

摘要：

由于CBC－MAC模式不可并行处理，提出了一种基于双重分组的并行认证模式(PKCB)。PKCB模式同并行认证模式PMAC相比，安全性和速率都有显著提高，PKCB认证模式与CTR（计数器）加密模式结合可构成分组密码算法的一种全工作模式。在此基础上提出了一种基于密钥计数的并行认证模式（KCTR－MAC）。KCTR－MAC模式安全性比PMAC模式高得多，而速率未降低，KCTR－MAC认证模式和CTR加密模式结合也可构成分组密码算法的一种全工作模式（2CTR），2CTR模式的综合性能不亚于标准模式CCM（CTR with CBC－MAC），是一种安全快速的实用模式。

关键词： 认证模式     CBC－MAC模式     PMAC模式     CTR模式     CCM模式    

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标题 作者 时间 类型 操作

human bioaccessibility of trace contaminants in size-fractionated red mud, derived precipitates and geopolymericblocks

Chunfeng Wang, Yanchen Zhu, Dan Yao, Guanfei Chen, Lianjun Wang

期刊论文

A continuous/discontinuous deformation analysis (CDDA) method based on deformable blocks for fracture

Yongchang CAI, Hehua ZHU, Xiaoying ZHUANG

期刊论文

Solution properties and self-association of multi-blocks like copolymer P(AM/AA) prepared by template

ZHANG Yuxi, WU Feipeng, LI Miaozhen, WANG Erjian

期刊论文

Strengthening Project Management to Attain Overseas Blocks with High Potential for Exploration

Shu-lin Zhang

期刊论文

Molecular dynamics study of water diffusion in an amphiphilic block copolymer with large difference in the blocks

Yang Zhou, Phillip Choi

期刊论文

Mechanisms of connective tissue formation and blocks of mitogen activated protein kinase

Irina A SHURYGINA, Michael G SHURYGIN, Nataliya I AYUSHINOVA, Galina B GRANINA, Nikolay V ZELENIN

期刊论文

木块在小尺寸轰燃实验中的点燃及预测模型

季经纬,宋虎,杨立中,范维澄

期刊论文

体外预应力凸块锚固区配筋设计研究

洪浩,童育强,贺志启,刘钊

期刊论文

基于双重分组和密钥计数的并行认证模式

黄玉划,胡爱群,宋宇波

期刊论文