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Characterization and phylogenetic analysis of a phenanthrene-degrading strain isolated from oil-contaminated soil

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Journal of Environmental Sciences 2004年第4期16卷 589-593页

作者： XIAYing MINHang LUZhen-mei YEYang-fang CollegeofLifeScience ZhejiangUniversityHangzhou310029China

Bacterium strain EVA17 was isolated from an oil-contaminated soil, and identified as Sphingomonas sp. based on analysis of 16S rDNA sequence,cellular fatty acid composition and physiological-chemical tests. The salicylate hydroxylase and catechol 2,3-dioxygenase(C23O) were detected in cell-free lysates, suggesting a pathway for phenanthrene catabolism via salicylate and catechol. Alignment showed that both of the C23O and GST genes of the strain EVA17 had high similarity with homologues of strains from genus Sphingomonas. The phylogenetic analysis based on 16S rDNA and C23O gene sequence indicated that EVA17 should be classified into genus Sphingomonas, although the two phylogenetic trees were slightly different from each other. The results of co-amplification and sequence determination indicated that GST gene should be located upstream of the C23O gene.

关键词： phenanthrene 16S rDNA glutathione S-transferase catechol 2,3-dioxygenase phylogenetic analysis

Electroless Plating of Thin Silver Films on Porous Al_2O_3 Substrate and the Study of Deposition Kinetics

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Tsinghua Science and Technology 2005年第6期10卷 680-689页

作者： fang mei Donglu Shi Department of Chemical and Materials Engineering University of Cincinnati Cincinnati OH 45221-0012 USA

A novel concept has been developed to coat the inner pore surfaces of reticulated alumina with a thin silver film by an electroless-plating method. As a result of coating, the porous alumina sample exhibits a sharp transition from insulating to conducting due to a thin silver layer on the inner pore surfaces. Systematic studies have been carried out to investigate the coating kinetics by employment of scanning electron microscope （SEM）, X-ray diffraction （XRD）, and computer simulation. Both coating procedures and effects of processing parameters on the quality of films are reported. Also, this paper presents the film bonding strength to the substrate, effects of sintering, and conduction mechanism of coated composite. The fundamental silver electroless-plating mechanism has been identified based on computer modeling. The simulation results indicate an excellent agreement between the silver deposition behavior and the physical model applied.

关键词： electroless plating thin silver films deposition kinetics

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Editorial

Science China(Physics,Mechanics & Astronomy) 2009年第11期52卷 1637-1638页

作者： Hongqi Zhang, mei Zhang, Jun Lin, Pengfei Chen & cheng fang On behalf of the Editorial Board of this issue

On August 1, 2008 a total solar eclipse was visible within a narrow corridor that traversed from North America to China. The path of the Moon’s umbral shadow started from Canada and extended

关键词： Editorial Zhang

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Tor被动流量分析综述

软件学报 2025年第1期36卷 253-288页

作者：梅汉涛程光朱怡霖周余阳东南大学网络空间安全学院江苏省泛在网络安全工程研究中心(东南大学) 网络空间国际治理研究基地(东南大学) 紫金山实验室

随着网络的蓬勃发展,用户隐私正面临着前所未有的挑战.人们开发出多种匿名通信系统来保护隐私,第2代洋葱路由Tor (the second-generation onion router)是目前最为广泛使用的匿名通信系统.然而,卓越的匿名性也使之成为不法分子犯罪的温... 详细信息

随着网络的蓬勃发展,用户隐私正面临着前所未有的挑战.人们开发出多种匿名通信系统来保护隐私,第2代洋葱路由Tor (the second-generation onion router)是目前最为广泛使用的匿名通信系统.然而,卓越的匿名性也使之成为不法分子犯罪的温床,如今Tor中充斥着非法交易、网络犯罪等. Tor被动流量分析通过被动观察网络流量对Tor进行去匿名化,已成为最热门的去匿名化技术.从Tor与流量分析基本概念出发,介绍Tor被动流量分析技术的应用场景与威胁模型.按照技术类型将现有工作分为流量分类技术与流关联技术,依据分析流程分别对比其流量采集方法、特征提取方法、使用算法.最后探讨当前研究面临的主要挑战与未来可能的研究趋势.

关键词： Tor 流量分析流量分类网站指纹流关联

A Co-Dominant Marker BoE332 Applied to Marker-Assisted Selection of Homozygous Male-Sterile Plants in Cabbage (Brassica oleracea *** L.)

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Journal of Integrative Agriculture 2013年第4期12卷 596-602页

作者： CHEN Chen ZHUANG Mu fang Zhi-yuan WANG Qing-biao ZHANG Yang-yong LIU Yu-mei YANG Li-mei cheng Fei Institute of Vegetables and Flowers Chinese Academy of Agricultural Sciences Horticulture College of Qingdao Agricultural University

The dominant genic male sterility （DGMS） gene CDMs399-3 derived from a spontaneous mutation in the line 79-399-3 of spring cabbage （Brassica oleracea var. capitata L.）, has been successfully applied in hybrid seed production of several cabbage cultivars in China. During the development of dominant male sterility lines in cabbage, the conventional identification of homozygous male-sterile plants （CDMs399-3/CDMs399-3） is a laborious and time-consuming process. For marker-assisted selection （MAS） of the gene CDMs399-3 transferred into key spring cabbage line 397, expressed sequence tag-simple sequence repeats （EST-SSR） and SSR technology were used to identify markers that were linked to CDMs399-3 based on method of bulked segregant analysis （BSA）. By screening a set of 978 EST-SSRs and 395 SSRs, a marker BoE332 linked to the CDMs399-3 at a distance of 3.6 cM in the genetic background of cabbage line 397 were identified. 7 homozygons male-sterile plants in population P1170 with 20 plants were obtained finally via MAS of BoE332. Thus, BoE332 will greatly facilitate the transferring of the gene CDMs399-3 into the key spring cabbage line 397 and improve the application of DGMS in cabbage hybrid breeding.

关键词： cabbage (Brassica oleracea var. capitata L.) dominant genic male sterility (DGMS) expressed sequencetag-simple sequence repeats (EST-SSR) bulked segregant analysis (BSA) marker-assisted selection (MAS)

肺痹方干预肺纤维化小鼠肺泡上皮细胞线粒体途径凋亡的机制

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中国组织工程研究 2025年第11期29卷 2334-2339页

作者：程雪荆焕熙张运克方泓河南中医药大学河南省郑州市450046 上海中医药大学附属龙华医院上海市200032

背景:研究表明,线粒体介导的肺泡上皮细胞凋亡在肺纤维化发病中起着重要的作用,而肺痹方可以减轻肺纤维化,抑制肺纤维化小鼠细胞外机制转化。目的:探讨肺痹方对博来霉素致肺纤维化小鼠肺泡上皮细胞线粒体途径凋亡的机制。方法:40只C57B... 详细信息

背景:研究表明,线粒体介导的肺泡上皮细胞凋亡在肺纤维化发病中起着重要的作用,而肺痹方可以减轻肺纤维化,抑制肺纤维化小鼠细胞外机制转化。目的:探讨肺痹方对博来霉素致肺纤维化小鼠肺泡上皮细胞线粒体途径凋亡的机制。方法:40只C57BL/6雄性小鼠随机分为空白对照组、模型组、吡非尼酮组、肺痹方组,每组10只。除空白对照组外,其他3组腹腔注射博来霉素[7.5 mg/(kg·d)]建立肺纤维化模型,连续注射10 d。造模后第1天各药物组小鼠灌胃给药[51.43/(kg·d)]吡非尼酮或[12.86 mg/(kg·d)肺痹方],连续给药28 d。用药结束后取材,采用苏木精-伊红染色和Masson染色观察小鼠肺组织的形态学变化,ELISA法检测血清中白细胞介素1、白细胞介素6、白细胞介素17、白细胞介素37水平,Western-blot法检测肺组织中Bax、Bcl-2、Beclin-1和Caspase3表达。结果与结论:①肺组织的形态学观察显示,模型组肺泡间隔及肺泡腔有大量炎症细胞浸润,出现大片融合成团的纤维灶;吡非尼酮组肺泡间隔增厚,炎症细胞少量浸润,出现肺纤维灶;肺痹方组肺泡结构增宽,少量的炎症细胞浸润,肺泡结构几乎无明显受损,少量肺纤维灶。②与空白对照组相比,模型组小鼠血清白细胞介素1、白细胞介素6、白细胞介素17和白细胞介素37质量浓度明显升高(P<0.01),两用药组明显低于模型组(P<0.01),肺痹方组低于非尼酮组。③与空白对照组相比,模型组小鼠肺组织Bax和Caspase3蛋白表达显著升高,两用药组均低于模型组;与空白对照组相比,模型组Bcl-2和Beclin-1蛋白表达显著降低,两用药组均高于模型组。④结论:肺痹方可以减轻肺纤维化,其机制可能与下调白细胞介素1、白细胞介素6、白细胞介素17和白细胞介素37水平,以及调节线粒体凋亡Bax、Bcl-2、Beclin-1和Caspase3相关蛋白从而减少肺泡上皮细胞凋亡有关。

关键词：肺痹方肺纤维化线粒体博来霉素 C57BL/6小鼠

THEORIES AND METHODS OF STRATEGIC ENVIRONMENTAL ASSESSMENT OF MODERN LOGISTICS DEVELOPMENT——A Case Study of Dalian City, China

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Chinese Geographical Science 2005年第2期15卷 145-150页

作者： XULing SHANGJin-cheng WANGYu-mei Northeast Institute of Geography and Agricultural Ecology Chinese Academy of ScieneesChangchun 130012P.R.China Graduate School of Chinese Academy of Sciences Beijing 100039P.R.China Department of Environmental Sciences and Engineering Northeast Normal UniversityChangchun 130024P.R.China

Modern logistics is a new industry during the construction of national economy. Based on analyzing the environmental problem that was led by the limitation of the strategy during enacting the program of the modern logistics, SEA for modern logistics was implemented. In this paper, procedure and indicator system in the SEA are constructed, and Environmental Check List to identify environmental impact factors of SEA for modern logistics is established. And a conception that indicates friendly degree of logistics system with resources and environment, degree of green, is introduced. With the example of modern logistics program of Dalian in China, two methods are applied, AHP and Fuzzy Comprehensive Evaluation Method, in the implement of SEA for modern logistics development. It is concluded that degree of green of modern logistics in Dalian is high. However, several important factors should be paid much attention to in the SEA for modern logistics as well as in the formulation and implement of modern logistics in Dalian.

关键词： modern logistics strategic environmental assessment (SEA) degree of green Dalian

Complex Modified Projective Synchronization for Fractional-order Chaotic Complex Systems

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International Journal of Automation and computing 2018年第5期15卷 603-615页

作者： Cui-mei Jiang Shu-Tang Liu fang-fang Zhang College of Control Science and Engineering Shandong University School of Electrical Engineering and Automation Qilu University of Technology

The aim of this paper is to study complex modified projective synchronization（CMPS） between fractional-order chaotic nonlinear systems with incommensurate orders. Based on the stability theory of incommensurate fractional-order systems and active control method, control laws are derived to achieve CMPS in three situations including fractional-order complex Lorenz system driving fractional-order complex Chen system, fractional-order real Rssler system driving fractional-order complex Chen system, and fractionalorder complex Lorenz system driving fractional-order real Lü system. Numerical simulations confirm the validity and feasibility of the analytical method.

关键词： Fractional-order system chaotic complex system incommensurate order complex modified projective synchronization(CMPS) active control.

Guaranteeing Wireless Communication Secrecy via a WFRFT-Based Cooperative System

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China Communications 2015年第9期12卷 76-82页

作者： fang Xiaojie Sha Xuejun mei Lin Communication Research Center Harbin Institute of Technology

In this paper, a weighted fractional Fourier transform(WFRFT) based cooperative overlay system, aiming to guarantee physical layer(PHY) security, is proposed. The paper elaborates how WFRFT and physical layer properties of the wireless medium are collaborated to guarantee the secrecy of wireless transmissions. In the proposed system, WFRFT is first preform on the secret data, such that the transmitted signal is distorted and can only be neutralized by inverse-WFRFT with the same parameter. And then two streams of the transformed sequences that bearing different messages are cooperatively and simultaneously transmitted to two legitimate receivers via a beamforming-liked method, respectively. In general, both the rapid spatial decorrelation property and the inherent security features of WFRFT are leveraged, such that only the eavesdropper's is degraded, and hence, the wireless communication secrecy is reliably guaranteed. Numerical simulations are conducted to evaluate the performance of the proposed system in terms of the average bit error rate and the secrecy capacity.

关键词： weighted fractional Fourier trans-form(WFRFT) physical layer(PHY) security secrecy capacity