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PP 2

ACE格式 1

AP1000 1

ENDF/B VII.0评价库 1

HDPE 1

MCNP 1

NJOY 1

WPC 1

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侧应力系数K₀ 1

初始应力状态 1

基于观测器的控制；奇异系统；分数阶；输入时滞；线性矩阵不等式 1

基础隔震 1

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Preparation and properties of nano SiO2 core-shell structured additives and their nanocomposite with polypropylene

KE Yangchuan, SUN Mingzhuo, SONG Yanxin, YANG GuangFu

《化学科学与工程前沿（英文）》 2007年第1卷第1期页码 76-80 doi: 10.1007/s11705-007-0016-6

摘要： To improve the performance of traditional nucleation additives and their compatibility with other additives, as well as to solve complex problems in practical applications, SiO precursors were reactively grafted in situ with the symmetrical hydroxyl groups of the nucleation agents. With this approach, the dissymmetrical part of the nucleation agents plays an important role. As a result, the prepared composite additive the nanoparticle precursor (NPP0) produces excellent results. The NPP0-PP composite has a transparency of over 93%, haze lower than 15%, and a heat distortion temperature (HDT) of 142?C, which is more than the 110?C of the pure PP matrix. In addition, it maintains over 90% of the mechanical properties with a deformation coefficient less than 1%. This indicates a strong nanoeffect.

关键词： deformation coefficient distortion temperature excellent NPP0-PP traditional nucleation

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麦秸粉与HDPE/PP基复合材料的制备及性能研究

杨兆哲,许民

《中国工程科学》 2014年第16卷第4期页码 30-33

摘要：

本文采用麦秸粉为增强体，分别与高密度聚乙烯（HDPE）、聚丙烯（PP）热塑性塑料基体采用挤出方式混合制备木塑复合材料，研究麦秸粉与HDPE、PP的配比对复合材料性能的影响。加入少量麦秸粉使木塑复合材料力学性能降低，随着麦秸粉含量的增加，复合材料的力学性能呈提高的趋势；当麦秸粉含量超过一定比例时，木塑复合材料力学性能降低，且冲击性能降低明显；本次试验HDPE基木塑复合材料力学强度略高于PP

关键词：麦秸粉 HDPE PP 复合材料性能研究

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Synthesis and characterization of macromolecular surface modifier PP--PEG for polypropylene

CHEN Hanjia, SHI Xuhua, ZHU Yafei, ZHANG Yi, XU Jiarui

《化学科学与工程前沿（英文）》 2008年第2卷第1期页码 102-108 doi: 10.1007/s11705-008-0018-z

摘要： A novel macromolecular surface modifier, polypropylene-grafted-poly(ethylene glycol) copolymer (PP--PEG), was synthesized by coupling polypropylene containing maleic anhydride with monohydroxyl-terminated poly(ethylene glycol). The effects of the reaction condition on the graft reactions were studied. The copolymers were characterized by IR, H NMR, thermogravimetry (TG) and differential scanning calorimetry (DSC). The results indicated that the graft reactions were hindered by increasing the molecular weight of PP or PEG. The graft copolymer was found to have a higher initial thermal degradation temperature and lower crystallization capacity as compared with pure PP, and the side chain of PEG hindered the PP chain from forming a perfect ? crystal. The thermal stability of PP--PEG decreased with the increasing content or molecular weight of PEG. The copolymers were blended with polypropylene to modify the surface hydrophilicity of the products. The results of attenuated total reflectance FTIR spectroscopy (ATR-FTIR) showed that PP--PEG could diffuse preferably onto the surface of the blends and be suitable as an effectual macromolecular surface modifier for PP.

关键词： polypropylene crystallization capacity attenuated hydrophilicity reflectance

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木粉/聚丙烯复合材料的非等温结晶动力学分析

黄浪,王海刚,王清文

《中国工程科学》 2014年第16卷第4期页码 21-24

摘要：

通过共混造粒热压方法制备聚丙烯（PP）基木塑复合材料（WPC），用差示扫描量热法研究其非等温结晶行为，分别用Jeziorny 法和Mo法对所得的数据进行处理分析结果表明：Jeziorny 法和Mo法能较理想地处理PP 基WPC的非等温结晶过程，复合材料中木粉的加入缩短了结晶时间，提高了PP 的结晶温度，降低了结晶速率。

关键词： PP WPC 非等温结晶结晶动力学

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以土体应力状态计算边坡安全系数的方法

王国体

《中国工程科学》 2006年第8卷第12期页码 80-84

摘要：土体不同条件下的应力状态表现为K₀效应和变化，它对坡体的安全度影响不可忽视。

关键词：侧应力系数K₀ 初始应力状态稳定安全系数公式

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Modeling and simulating the impact of forgetting and communication errors on delays in civil infrastructure shutdowns

Zhe SUN, Cheng ZHANG, Pingbo TANG

《工程管理前沿（英文）》 2021年第8卷第1期页码 109-121 doi: 10.1007/s42524-019-0084-6

摘要： Handoff processes during civil infrastructure operations are transitions between sequential tasks. Typical handoffs constantly involve cognitive and communication activities among operations personnel, as well as traveling activities. Large civil infrastructures, such as nuclear power plants (NPPs), provide critical services to modern cities but require regular or unexpected shutdowns (i.e., outage) for maintenance. Handoffs during such an outage contain interwoven workflows and communication activities that pose challenges to the cognitive and communication skills of handoff participants and constantly result in delays. Traveling time and changing field conditions bring additional challenges to effective coordination among multiple groups of people. Historical NPP records studied in this research indicate that even meticulous planning that takes six months before each outage could hardly guarantee sufficient back-up plans for handling various unexpected events. Consequently, delays frequently occur in NPP outages and bring significant socioeconomic losses. A synthesis of previous studies on the delay analysis of accelerated maintenance schedules revealed the importance and challenges of handoff modeling. However, existing schedule representation methods could hardly represent the interwoven communication, cognitive, traveling, and working processes of multiple participants collaborating on completing scheduled tasks. Moreover, the lack of formal models that capture how cognitive, waiting, traveling, and communication issues affect outage workflows force managers to rely on personal experiences in diagnosing delays and coordinating multiple teams involved in outages. This study aims to establish formal models through agent-based simulation to support the analytical assessment of outage schedules with full consideration of cognitive and communication factors involved in handoffs within the NPP outage workflows. Simulation results indicate that the proposed handoff modeling can help predict the impact of cognitive and communication issues on delays propagating throughout outage schedules. Moreover, various activities are fully considered, including traveling between workspaces and waiting. Such delay prediction capability paves the path toward predictive and resilience outage control of NPPs.

关键词： NPP outage human error team cognition handoff modeling

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Application of Fe

Xiaowei ZHANG,Qinyan YUE,Dongting YUE,Baoyu GAO,Xiaojuan WANG

《环境科学与工程前沿（英文）》 2015年第9卷第3期页码 402-410 doi: 10.1007/s11783-014-0659-8

摘要： Dyes are common pollutants in textile wastewaters, and the treatment of the wastewater has now attracted much attention due to its wide application and low biodegradability. In this study, Fe /C/Clay ceramics, a kind of novel micro-electrolysis filler, were sintered and employed in a dynamic micro-electrolysis reactor for synthetic Acid Red 73 (AR73) and Reactive Blue 4 (RB4) wastewater treatment. The effects of influent pH, hydraulic retention time (HRT), and aeration on the decoloration efficiencies of AR73 and RB4 were studied. The optimum conditions for wastewater treatment were: AR73, influent pH of 4, HRT of 2 h and aeration; RB4, influent pH of 5, HRT of 6 h and aeration. Under the optimum conditions, decoloration efficiency of AR73 and RB4 wastewater was 96% and 83%, respectively. Results of UV-vis spectrum scanning demonstrated that the chromophores were broken. Continuous running tests showed that improvement of micro-electrolysis system with Fe /C/Clay ceramics for AR73 and RB4 synthetic wastewater treatment could avoid failure of micro-electrolysis reactor, which indicated great potential for the practical application of the ceramics in the field of actual industrial wastewater treatment.

关键词： Fe⁰/C/Clay ceramics micro-electrolysis Acid Red 73 Reactive Blue 4 synthetic wastewater

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基于医院中子照射器I型堆的MCNP中子截面库研制

王立鹏,江新标,赵柱民,朱养妮,陈立新,周永茂

《中国工程科学》 2012年第14卷第8期页码 42-46

摘要：

利用NJOY程序制作了用于医院中子照射器I型堆（in-hospital neutron irradiator mark 1 reactor，IHNI-1）物理计算的MCNP中子截面库。着重考虑了反应堆运行温度范围内的温度点，制作了多温度点ACE(a compact ENDF)格式中子截面数据库。利用MCNP/4B自带库验证了自制库的正确性，利用ICSBEP（International Criticality Safety Benchmark Evalution Project，国际临界安全基准评价工程手册）基准题对结果进行了验证和反应性温度系数计算，分析了不同参数的影响作用。结果表明，所制作的截面库是正确的，能够用于IHNI-1反应堆物理设计计算。

关键词： NJOY ENDF/B VII.0评价库 MCNP ACE格式

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Investigation on multiple-melting behavior of nano-CaCO3/polypropylene composites

LIN Zhidan, ZENG Chunlian, MAI Kancheng

《化学科学与工程前沿（英文）》 2007年第1卷第1期页码 81-86 doi: 10.1007/s11705-007-0017-5

摘要： The multiple melting-peak behavior of polypropylene (PP) in nano-CaCO/PP composites and modified nano-CaCO/PP composites were investigated under the condition of isothermal crystallization and nonisothermal crystallization. The result indicated that the addition of nano-CaCO markedly increased the crystallization temperatures of PP and induced the formation of the β-crystal of PP. The crystallization temperatures of nano-CaCO/PP composites modified by reactive monomers were further increased, but the melting-peak intensity of the β-crystal of PP was not greatly influenced. While in the presence of dicumyl peroxide, nano-CaCO/PP composites modified by reactive monomers led to the significant increase in the melting-peak intensity of the β-crystal of PP. The double melting-peak of PP was observed, which was attributed to the formation of two kinds of different crystallization forms of α-crystal or β-crystal during the crystallization of PP. With the increase of crystallization temperatures, the double melting-peak moved toward the high-temperature side. The intensity of high-temperature melting peak was higher than that of low-temperature melting peak in nano-CaCO/PP composites. While in modified nano-CaCO/PP composites crystallized at higher temperature, the intensity of high-temperature melting peak was lower than that of low-temperature melting peak. The isothermal crystallization time had little effect on the melting temperatures.

关键词： polypropylene nano-CaCO/PP presence melting-peak behavior low-temperature

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An electrochemical process that uses an Fe

Chaojie Jiang, Lifen Liu, John C. Crittenden

《环境科学与工程前沿（英文）》 2016年第10卷第4期 doi: 10.1007/s11783-016-0860-z

摘要： A bio-electrochemical fuel cell reactor with cathodic Fe /TiO generates electricity. It destroys recalcitrant pollutants in cathode chamber without photocatalysis. Fe /TiO generates reactive oxygenated species in the dark or under photocatalysis. Cathodic produced ROS (hydroxy radical/superoxide radical) can degrade tetracycline or dyes. Electricity generation is enhanced by semiconductor catalyzed cathodic degradation of pollutants. In this study, a new water treatment system that couples (photo-) electrochemical catalysis (PEC or EC) in a microbial fuel cell (MFC) was configured using a stainless-steel (SS) cathode coated with Fe /TiO . We examined the destruction of methylene blue (MB) and tetracycline. Fe /TiO was prepared using a chemical reduction-deposition method and coated onto an SS wire mesh (500 mesh) using a sol technique. The anode generates electricity using microbes (bio-anode). Connected via wire and ohmic resistance, the system requires a short reaction time and operates at a low cost by effectively removing 94% MB (initial concentration 20 mg·L ) and 83% TOC/TOC under visible light illumination (50 W; 1.99 mW·cm for 120 min, MFC-PEC). The removal was similar even without light irradiation (MFC-EC). The of the MFC-PEC system was approximately 0.675 kWh·m ·order , whereas that of the MFC-EC system was zero. The system was able to remove 70% COD in tetracycline solution (initial tetracycline concentration 100 mg·L ) after 120 min of visible light illumination; without light, the removal was 15% lower. The destruction of MB and tetracycline in both traditional photocatalysis and photoelectrocatalysis systems was notably low. The electron spin-resonance spectroscopy (ESR) study demonstrated that ·OH was formed under visible light, and ·O was formed without light. The bio-electricity-activated O and ROS (reactive oxidizing species) generation by Fe /TiO effectively degraded the pollutants. This cathodic degradation improved the electricity generation by accepting and consuming more electrons from the bio-anode.

关键词： Bio-anode Photocatalytic cathode Fe⁰/TiO₂ ESR Dye and antibiotics Advanced oxidation

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Optimization of remanufacturing process routes oriented toward eco-efficiency

Hong PENG, Han WANG, Daojia CHEN

《机械工程前沿（英文）》 2019年第14卷第4期页码 422-433 doi: 10.1007/s11465-019-0552-z

摘要： Remanufacturing route optimization is crucial in remanufacturing production because it exerts a considerable impact on the eco-efficiency (i.e., the best link between economic and environmental benefits) of remanufacturing. Therefore, an optimization model for remanufacturing process routes oriented toward eco-efficiency is proposed. In this model, fault tree analysis is used to extract the characteristic factors of used products. The ICAM definition method is utilized to design alternative remanufacturing process routes for the used products. Afterward, an eco-efficiency objective function model is established, and simulated annealing (SA) particle swarm optimization (PSO) is applied to select the manufacturing process route with the best eco-efficiency. The proposed model is then applied to the remanufacturing of a used helical cylindrical gear, and optimization of the remanufacturing process route is realized by MATLAB programming. The proposed model’s feasibility is verified by comparing the model’s performance with that of standard SA and PSO.

关键词： remanufacturing process route optimization eco-efficiency simulated particle swarm optimization algorithm IDEF0

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Effect of inhibiting tyrosine kinase Src expression on protein phosphatase 2A and tau phosphorylation

LIU Rong, ZENG Ji, ZHOU Xinwen, WANG Jianzhi, PEI Jinjing

《医学前沿（英文）》 2008年第2卷第3期页码 235-238 doi: 10.1007/s11684-008-0044-8

摘要： The aim of this study is to investigate the effect of tyrosine kinase Src on Tyrosine 307(Y307) phosphorylation, protein phosphatase 2A (PP2A) activity, and on tau phosphorylation. Specific Src siRNA was transfected into cultured mouse neuroblastoma N2a cells to inhibit the expression of Src protein, and the phosphorylation levels of PP2A Y307 and tau at different sites, as well as PP2A activity were detected at different time points after siRNA transfection. Twelve hours after siRNA transfection, the protein level of Src was dramatically decreased, with decreased PP2A Y307 phosphorylation. However, the total PP2A protein level was also decreased, together with a decreased PP2A activity. Tau was hyperphosphorylated at the Ser198/199/202 sites. Multiple factors may be involved in the cellular regulation of PP2A activity. Inhibiting Src expression could induce inactivation of PP2A and tau hyperphosphorylation.

关键词： hyperphosphorylation PP2A activity cellular regulation siRNA siRNA transfection

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秦山二期核电站的自主创新

叶奇蓁,杨兰和

《中国工程科学》 2008年第10卷第1期页码 23-32

摘要：

论述了秦山二期核电工程主要的自主创新内容，包括新的堆芯设计，为此进行的试验研究和计算分析，以及为新堆所作的流致振动试验、分析和堆上实测；针对二环路的安全系统的改进及相应的安全分析，以提高其安全冗余度；根据二环路的特点对核电站的参数及其配套的设备设计进行了优化，使得核电站的出力达到最大；主厂房和常规岛厂房根据二环路及厂址的特点进行了创新。自主研制了控制棒驱动机构和装卸料机，其性能超出了设计指标；采取多种方法式使大部分主设备实施国产化。在土建安装上实施了穹顶整体吊装。在调试方面实施了汽轮发电机组的非核蒸汽冲转

关键词：核能工程二期

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Histone variants: critical determinants in tumour heterogeneity

Tao Wang, Florent Chuffart, Ekaterina Bourova-Flin, Jin Wang, Jianqing Mi, Sophie Rousseaux, Saadi Khochbin

《医学前沿（英文）》 2019年第13卷第3期页码 289-297 doi: 10.1007/s11684-018-0667-3

摘要： Malignant cell transformation could be considered as a series of cell reprogramming events driven by oncogenic transcription factors and upstream signalling pathways. Chromatin plasticity and dynamics are critical determinants in the control of cell reprograming. An increase in chromatin dynamics could therefore constitute an essential step in driving oncogenesis and in generating tumour cell heterogeneity, which is indispensable for the selection of aggressive properties, including the ability of cells to disseminate and acquire resistance to treatments. Histone supply and dosage, as well as histone variants, are the best-known regulators of chromatin dynamics. By facilitating cell reprogramming, histone under-dosage and histone variants should also be crucial in cell transformation and tumour metastasis. Here we summarize and discuss our knowledge of the role of histone supply and histone variants in chromatin dynamics and their ability to enhance oncogenic cell reprogramming and tumour heterogeneity.

关键词： cancer-testis TH2B TH2A H1T H1.0 H1F0 linker histones

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Experience gained in analyzing severe accidents for WWER RP using CC SOCRAT

《能源前沿（英文）》 2021年第15卷第4期页码 872-886 doi: 10.1007/s11708-021-0796-2

摘要： The current Russian regulatory documents on the safety of nuclear power plant (NPP) specify the requirements regarding design basis accidents (DBAs) and beyond design basis accidents (BDBAs), including severe accidents (SAs) with core meltdown, in NPP design (NP-001-15, NP-082-07, and others). For a rigorous calculational justification of BDBAs and SAs, it is necessary to develop an integral CC that will be in line with the requirements of regulatory documents on verification and certification (RD-03-33-2008, RD-03-34-2000) and will allow for determining the amount of data required to provide information within the scope stipulated by the requirements for the structure of the safety analysis report (SAR) (NP-006-16). The system of codes for realistic analysis of severe accidents (SOCRAT) (formerly, thermohydraulics (RATEG)/coupled physical and chemical processes (SVECHA)/behavior of core materials relocated into the reactor lower plenum (HEFEST)) was developed in Russia to analyze a wide range of SAs at NPP with water-cooled water-moderated power-generating reactor (WWER) at all stages of the accident. Enhancements to the code and broadening of its applicability are continually being pursued by the code developers (Nuclear Safety Institute of the Russian Academy of Sciences (IBRAE RAN)) with OKB Gidropress JSC and other organizations. Currently, the SOCRAT/1 code can be used as a base tool to obtain realistic estimates for all parameters important for computational justification of the reactor plant (RP) safety at the in-vessel stage of SAs with fuel melting. To perform analyses using CC SOCRAT/1, the experience gained during execution of thermohydraulic codes is applied, which allows for minimizing the uncertainties in the results at the early stage of an accident scenario. This study presents the results of the work performed in 2010–2020 in OKB Gidropress JSC using the CC SOCRAT/1. Approaches have been considered to develop calculational models and analyze SAs using CC SOCRAT. This process, which is clearly structured in OKB Gidropress JSC, provides a noticeable reduction in human involvement, and reduces the probability of erroneous results.

关键词： system of codes for realistic analysis of severe accidents (SOCRAT) design basis accidents (DBAs) severe accidents (SAs) computer code (CC) nuclear power plant (NPP) design water-cooled water-moderated (WWER) modeling model safety requirements