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Chinese Journal of Polymer Science 2023年第8期41卷 1287-1297,I0010页

作者： zhou-xian Li Yi-Ran Kong xiang-Fei Chen Ya-Jiang Huang Ya-Dong Lv Guang-xian Li College of polymer science and engineering State key laboratory of polymer materials engineering of ChinaSichuan UniversityChengdu 610065China

The aging of natural rubber(NR)at high temperatures will seriously affect its service lifetime in many key *** the present work,the changes in microstructure and mechanical properties of semi-efficient vulcanized NR/carbon black(CB)vulcanizates during thermooxidative aging at high temperatures(150-200℃)and a moderate temperature(95℃)were *** high temperatures,a two-stage aging behavior,which was characteristic of a first rapid decline and then a continuous rise in the crosslinking density(ve),was identified and was found to be closely related to the depletion behavior of *** surface cracking behavior observed in the second stage of high-temperature aging was discussed in terms of the grafting reaction of macromolecular radicals on CB particles and thermal *** contrast,the aging of NR at moderate temperatures was much mild,which featured a continuous increase in ve and an oxidation mechanism dominated by peroxy radicals attacking double *** general,the mechanical properties of NR vulcanizates during high-temperature aging depended on the competition effects of structural evolution in the crosslinked network and oxidation-induced chain scission.

关键词： Natural rubber nanocomposites High-temperature Thermo-oxidative aging

Cleaner geopolymer prepared by co-activation of gasification coal fly ash and steel slag:durability properties and economic assessment

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Frontiers of Environmental Science & Engineering 2023年第12期17卷 109-121页

作者： xian zhou Xia Chen Ziling Peng Yongmen zhou Yan Li Wang Jian Zeyu Fan Yuchi Chen Key Laboratory of Geotechnical Mechanics and Engineering of Ministry of Water Resources Changjiang River Scientific Research InstituteWuhan 430010China Jiangxi Research Center on Hydraulic Structures Jiangxi Provincial Institute of Water SciencesNanchang 330029China Key Joint Laboratory of Environment Simulation and Pollution Control School of EnvironmentTsinghua UniversityBeijing 100084China

Geopolymer is a material with high early ***,the insufficient durability properties,such as long-term strength,acid-base resistance,freeze-thaw resistance,leaching toxicity,thermal stability,sulfate resistance and carbonation resistance,restrain its practical ***,a longterm stable geopolymer composite with high final strength(ASK1)was synthesized from shell coal gasification fly ash(SFA)and steel slag(SS).Additionally,a geopolymer composite with high early strength(ASK2)was also synthesized for *** results showed that ASK1 exhibited better performance on freezing-thawing resistance,carbonization resistance and heavy metals stabilization compared to the ASK2 at long-term *** the curing temperature could accelerate the unconfined compressive strength(UCS)development at initial curing ages of 3 to 7 *** ASK1 and ASK2 exhibited excellent acid-base and sulfate corrosion *** increase for UCS was seen under KOH solution and MgSO_(4)solution corrosion for *** leaching concentrations of heavy metals out of the two geopolymers were below the standard threshold,even after 50 freezingthawing *** ASK1 and ASK2 geopolymer concrete exhibited higher sustainability and economic efficiency than Portland cement *** result of this study not only provides a suitable way for the utilization of industrial solid waste in civil and environmental engineering,but also opens a new approach to improve the long-term stabilities of the geopolymers.

关键词： Geopolymer Shell coal gasification fly ash Steel slag Heavy metal Solidification/stabilization Durability

Two Phase Flow Simulation of Fractal Oil Reservoir Based on Meshless Method

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Energy Engineering 2022年第2期119卷 653-664页

作者： xian zhou Fei Wang Ziyu Wang Yunfeng Xu School of Petroleum Engineering Yangtze UniversityWuhan430100China China Oilfield Services Limited TianjinChina Xinmin Oil Production Plant of Jilin Oilfield Company PetroChinaSongyuan138000China

The reservoir is the networked rock skeleton of an oil and gas trap,as well as the generic term for the fluid contained within pore fractures and karst *** and a complex internal pore structure characterize the reservoir *** introducing the fractal permeability formula,this paper establishes a fractal mathematical model of oil-water two-phase flow in an oil reservoir with heterogeneity characteristics and numerically solves the mathematical model using the weighted least squares meshless ***,the method’s correctness is verified by comparison to the exact *** numerical results demonstrate that the fractal oil-water two-phase flow mathematical model developed using the meshless method is capable of more accurately and efficiently describing the flow characteristics of the oil-water two-phase migration *** comparison to the conventional numerical model,this method achieves a greater degree of convergence and *** paper examines the effect of varying the initial viscosity of the oil,the initial formation pressure,and the production and injection ratios on daily oil production per well,water cut in the block,and accumulated oil in the *** 10 and 60 cp initial crude oil viscosities,the water cut can be 0.62 and 0.80,with 3100 and 1900 m^(3)cumulative oil *** pressures have little effect on *** this case,the daily oil production of well PRO1 is 1.7 m^(3)at 7 and 10 MPa initial *** cumulative oil production is 3465.4 and 2149.9m^(3)when the production injection ratio is 1.4 and *** two-phase meshless method described in this paper is essential for a rational and effective study of production dynamics patterns in complex reservoirs and the development of reservoir simulations of oil-water flow in heterogeneous reservoirs.

关键词： Oil-water two-phase flow fractal theory weighted least square method meshless method

Energy Level Statistics of SO（5） Limit of Super-symmetry U（6/4） in Interacting Boson-Fermion Model

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Communications in Theoretical Physics 2005年第5X期44卷 897-900页

作者： BAI Hong-Bo ZHANG Jin-Fu zhou xian-Rong Department of Physics Chifeng University Chifeng 024001 China Department of Physics Liaoning Normal University Dalian 116029 China

We study the energy level statistics of the SO(5) limit of super-symmetry U(6/4) in odd-A nucleus using the interacting boson-fermion model. The nearest neighbor spacing distribution (NSD) and the spectral rigidity (△3)are investigated, and the factors that affect the properties of level statistics are also discussed. The results show that the boson number N is a dominant factor. If N is small, both the interaction strengths of subgroups SOB(5) and SOBF(5)and the spin play important roles in the energy level statistics, however, along with the increase of N, the statistics distribution would tend to be in Poisson form.

关键词： interacting boson-fermion model SO(5) limit of super-symmetry U(6/4) odd-A nucleus levelstatistics energy levels unfolding nearest neighbor spacing distribution spectral rigidity

Universal composable secure protocol for EPC system

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The Journal of China Universities of Posts and Telecommunications 2013年第1期20卷 115-121,128页

作者： XIAO Feng zhou Ya-jian zhou Jing-xian ZHU Hong-liang NIU Xin-xin Information Security Center Beijing University of Posts and Telecommunications

As an important component of internet of things, electronic product code （EPC） system is widely used in many areas. However, the mass deployment of EPC system is frequently degraded by security and privacy problems. Therefore, the major researches focus on the design of a secure EPC system with high efficiency. This paper discusses the security requirements of EPC system and presents a universal composable （UC） model for EPC system, the ideal functionality of EPC system is also formally defined with the UC framework. Then a secure protocol for EPC system under UC framework is proposed and the analysis of security and performance of the proposed protocol is given, in comparison with other protocols, the results show that the proposed protocol is UC secure and can provide privacy protection, untraceability, authorized access, anonymity and concurrent security for EPC system. Furthermore, less computation and storage resource are required by the proposed protocol.

关键词： EPC system universal composable secure protocol privacy protection

Effect of rare earths on selective hydrogenation of p-chloronitrobenzene over PtMOx/CNTs catalysts

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Chinese Chemical Letters 2009年第1期20卷 96-98页

作者： Xiao xiang Han Jian Rong Li Ren xian zhou Department of Applied Chemistry College of Food Science & Biotechnology Engineering Zhejiang Gongshang University Hangzhou 310035 China Institute of Catalysis Zhejiang University Hangzhou 310028 China

The effect of rare earths （Sm, Pr, Ce, Nd and La） on the hydrogenation properties ofp-chloronitrobenzene （CNB） over Pt/CNTs catalyst was studied in ethanol at 303 K and normal pressure. The results exhibited that the hydrogenation of p-CNB could be carried out over PtMOx/CNTs catalysts. Both catalytic activities and yields ofp-chloroaniline （CAN） were all improved. PtCeOx/ CNTs catalyst exhibited the best catalytic activity （TOF was 0.47 s^-1） and the highest yield of p-CAN （97.5 mol%）. PtCeOx/CNTs （1.0 wt%） catalyst exhibited good stability on the hydrogenation of p-CNB.

关键词： Rare earths Chloronitrobenzene Chloroaniline Carbon nanotubes (CNTs) Hydrogenation

Species-area relationship within and across functional groups at alpine grasslands on the northern Tibetan Plateau,China

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Journal of Mountain Science 2016年第2期13卷 265-275页

作者： zhou Nan WU Jian-shuang SHEN Zhen-xi ZHANG xian-zhou YANG Peng-wan Lhasa National Ecological Research Station Key Laboratory of Ecosystem Network Observation and ModellingInstitute of Geographic Sciences and Natural Resources ResearchChinese Academy of sciences University of Chinese Academy of Sciences Functional Biodiversity Dahlem Centre of Plant SciencesFree University of Berlin

The species-area relationship （SAR） is one of the most fundamental concepts in community ecology and is helpful for biodiversity conservation. However, few studies have systematically addressed this topic for different alpine grassland types on the Tibetan Plateau, China. We explored whether the plant composition of different functional groups affects the manner in which species richness inereases with increasing area at scales ≤ 1.0 m^2. We also compared species richness （S） within and across forbs, legumes, sedges and grasses, with sampling subplot area （A） increasing from 0.0625 m^2 to 1.0 m^2 between alpine meadow and steppe communities. We applied a logarithmic function （S = b0 ＋ b1 ln A） to determine the slope and intercept of SAR curves within and across functional groups. The results showed that the logarithmic relationship holds true between species richness and sampling area at these small scales. Both the intercept and slope of the logarithmic forbs-area curves are significantly higher than those for the three other functional groups （P 〈 0.05）. Forb accounts for about 91.9 % of the variation in the intercept and 75.0% of the variation in the slope of the SAR curve when all functional groups＇ data were pooled together. Our results indicated that the different SAR patterns should be linked with species dispersal capabilities, environmental filtering, and life form composition within alpine grassland communities. Further studies on the relationship between species diversity and ecosystem functions should specify the differential responses of different functional groups to variations in climate and anthropogenic disturbances.

关键词： Changtang Nature Reserve Complementary response Plant functional groups Plant life forms Species coexistence

Microplastics may reduce the fish bioaccumulation of organic pollutants

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Science China(Technological Sciences) 2024年第10期67卷 3079-3090页

作者： YANG Bing zhou xian HU XiaoJie QIN Chao WANG Jian GAO YanZheng Institute of Organic Contaminant Control and Soil Remediation College of Resource and Environmental SciencesNanjing Agricultural UniversityNanjing 210095China

Microplastics have frequently been regarded as a threat to aquatic organisms due to their potential to enhance the accessibility of organic ***,studies of microplastics as“carriers”in the process of bioaccumulation have only been conducted on a few organic *** this study,we employed machine learning algorithms to predict the sorption capacity of 83 exogenous organic pollutants(in CCL4)on microplastics,the prediction model exhibits exceptional predictive performance,achieving R^(2) values of 0.8651 and 0.6962,RMSE values of 0.4625 and 0.1841 for the sorption coefficients Kf and n,respectively,and quantitatively estimated the contribution of microplastics to the bioaccumulation levels of organic pollutants in Gadus *** considering both natural and microplastic-ingesting pathways,we demonstrated that the ingestion of microplastics containing organic pollutants facilitates the entry of organic pollutants into Gadus ***,due to their robust sorption capacity,microplastics transport the organic pollutants accumulated through the natural pathway out of the fish,thereby preventing *** findings elucidate the“cleaning”mechanism of microplastics concerning various organic pollutants in aquatic organisms,providing valuable insights for accurately assessing the risk of microplastics in aquatic environments.

关键词： microplastics aquatic organisms organic pollutants machine learning risks

用公益推动乡村儿童美育:北京新艺动社会工作发展中心联合创始人兼理事长龚瑜访谈

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公共艺术 2024年第2期 86-90页

作者：周娴不详

近年来,美育因在社会发展中发挥了积极作用而备受关注。越来越多的力量加入进来,共同推动了中国社会美育的发展。但是对于乡村儿童群体的关注,还是从近十年才开始,除了高校、企业外,公益组织成为乡村儿童美育一股重要的推动力量。为了... 详细信息

近年来,美育因在社会发展中发挥了积极作用而备受关注。越来越多的力量加入进来,共同推动了中国社会美育的发展。但是对于乡村儿童群体的关注,还是从近十年才开始,除了高校、企业外,公益组织成为乡村儿童美育一股重要的推动力量。为了解公益组织在社会美育中发挥的积极作用,尤其是对于乡村儿童群体,本期特邀北京新艺动社会工作发展中心联合创始人兼理事长、全国乡村儿童美育公益行动网络执委会代表、浙江致朴公益基金会首席美育官龚瑜进行访谈,围绕公益组织参与乡村儿童美育的现状、模式及其发挥的作用等问题,进行了深入的交流,并从实践的角度分享公益组织参与社会美育的经验。

关键词：社会美育公益组织儿童群体公益基金会公益行动儿童美育发挥的作用访谈

Antitumor activity of nervosine Ⅶ,and the crosstalk between apoptosis and autophagy in HCT116 human colorectal cancer cells

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Chinese Journal of Natural Medicines 2020年第2期18卷 81-89页

作者： HUANG Shuai ZHAO Shuang-Mei SHAN Lian-Hai zhou xian-Li School of Life Science and Engineering Southwest Jiaotong UniversityChengdu 610031China

Nervosine Ⅶ is one of the known saturated pyrrolizidine alkaloids isolated from the plant of Liparis *** is first study to investigate the antitumor activity of nervosine Ⅶ in vitro,and the results indicated that nervosine Ⅶ induced autophagy and apoptosis in HCT116 human colorectal cancer *** studies showed that nervosine Ⅶ-induced apoptosis was associated with the intrinsic pathway by the activation of caspase-9,-3 *** induced by nervosine Ⅶ was characteristic with the regulation of autophagic markers including the increase of LC3-Ⅱ and beclin 1 proteins,and the decrease of p62 *** Ⅶ simultaneously induced autophagy and apoptosis by activated MAPKs signaling pathway including JNK,ERK1/2 and p38,suppressing the p53 signaling pathway.

关键词： Liparis nervosa Pyrrolizidine alkaloids NervosineⅦ Autophagy Apoptosis HCT116 cells