One Method of Standard Recognition of Underwater Acoustic Signal

研究了制式识别的特征参数提取方法,以小波变换为主,结合瞬时频率统计算法、高阶谱等多种识别算法,对现有水下通信信号调制方式进行类间、类内识别,包括多载波（OFDM）和单载波（MFSK、MPSK和QAM）。仿真结果表明,文章所采用的方法在低信噪比下的识别概率均能保持在82%以上,具有较好的识别性能。This article did a research on themethod of characteristic parameter obtainment. Based on Wavelet Transform, instantaneous parameter extraction and higher-order cumulants are used to recognize the Underwater Sound Signal, including Single carrier（MFSK,MPSK, QAM） and multicarrier（OFDM）. Simulation results show that the rate of modulation identification is able to keep 82% above in the situation of low SNR, meaning that the proposed method has a good ability of identification.国家自然科学基金（61471309,61671394）; 中央高校基本科研业务费专项资金（20720170044

Enrichment of Heavy Metals by Casuarina equisetifolia of Different Stand Ages

为认识木麻黄(Casuarina equisetifolia)防护林带重金属消减效应,利用电感耦合等离子体质谱(ICP-MS)测定了福建省平潭国有防护林场林龄分别为5,15,20,30年的木麻黄小枝、细根、凋落物及林地土壤中5种重金属(Cr、Cu、Zn、Cd和Pb)的含量.结果表明:平潭木麻黄林地土壤重金属Cr、Cu、Zn、Pb、Cd含量均低于福建省土壤和福建海岸带土壤的重金属含量背景值,未发现重金属污染;木麻黄Cr、Cd和Zn的平均含量高出普通植物的正常值范围,木麻黄中重金属含量依Zn>Cr>Pb>Cu>Cd顺序降低;木麻黄细根中的重金属含量最高,且细根对重金属的富集系数也最高;木麻黄对Cr、Cu、Zn、Cd的富集系数均大于1;木麻黄细根中Zn、Cu元素含量显著正相关;小枝对Cr、Cd和Pb,细根对Zn的富集系数均与林龄极显著正相关;木麻黄现存生物量中,Cr、Cu、Zn、Cd和Pb的现存储量分别为3.06~3.46 kg/hm2,1.14~1.57kg/hm2,11.67~12.57 kg/hm2,0.05~0.09 kg/hm2和0.45~1.84 kg/hm2,且主要存在于根和树干中;随着林龄的增加,木麻黄积累大量的重金属,并达到其峰值.综上所述,木麻黄防护林在防风固沙的同时,能够吸收富集大量的重金属,对海岸带的重金属污染具有明显的消减作用.Casuarina equisetifolia is the key species in the seashore shelter belt in Fujian Province.It is necessary to assess enrichment of heavy metals by C. equisetifolia.Concentrations of heavy metals,including Cr,Cu,Zn,Cd and Pb,in branchlet,fine root,litter and soil of C.equisetifolia in 4 ages( 5,15,20,30 a) were determined.There was no heavy metal pollution in the shelter belt soil. The results showed that the content of the heavy metals in C. equisetifolia could be ranked from high to low as Zn>Cr>Pb>Cu>Cd.The heavy metal content of the fine root was significantly higher than the other parts,and the concentration coefficient of the fine root was also the highest in C. equisetifolia.There was a significant positive correlation between the content of Zn and Cu in the fine root. The concentration coefficients of Cr,Cd,Pb in branchlet,and the concentration coefficient of Zn in the fine root were significantly correlated with stand age.Existing reserves of Cr,Cu,Zn,Cd and Pb were 3. 06-3. 46 kg / hm2,1. 14-1. 57 kg/hm2,11. 67-12. 57 kg/hm2,0. 05-0. 09 kg/hm2,0. 45-1. 84 kg/hm2. Heavy metals mainly existed in the root and trunk.C. equisetifolia had the capability of accumulating heavy metals during growth,and the potential to reduce heavy metal pollution.国家自然科学基金(41176090);; 国家科技支撑计划(2009BADB2B0302

Characterization of Condensed Tannins from Litchi Seed by Reflectron Modes and Linear Modes of MALDI-TOF MS

E-mail: [email protected][中文文摘]利用不同模式的基质辅助激光解吸电离飞行时间质谱(MALDI-TOF MS)分析荔枝果核缩合单宁.在反射模式(Reflectron modes)下,加速电压20.0 kV,反射电压23.0 kV,延时取出电压16.32 kV,聚焦电压9.45 kV,获得缩合单宁的准确结构单元组成和连接方式信息,其为三聚体至十八聚体组成的A型原花青定多聚物.在线性模式(Linear modes)下,加速电压20.0 kV,延时取出电压16.25 kV,聚焦电压10.0 kV,检测到十九聚体至二十七聚体的缩合单宁信号,其更全面获取缩合单宁聚合度的分布信息.综合两种模式,荔枝果核缩合单宁是由三聚体至二十七聚体分布的A型原花青定多聚物.探讨了一种联合反射模式与线性模式对植物单宁结构准确分析的基质辅助激光解吸电离飞行时间质谱方法.[英文文摘]Condensed tannins from litchi seed were analyzed using reflectron modes and linear modes of matrix-assisted laser desorption/ionization time-of-flight mass spectrometry(MALDI-TOF MS).The reflectron modes(accelerating voltage,20.0 kV;reflectron voltage,23.0 kV;delayed extraction voltage,16.32 kV;lens voltage,9.45 kV) spectra obtained clear information on basic unit,interflavan linkage and polymerization degree extended from 3-mers to 18-mers.The linear modes(accelerating voltage,20.0 kV;delayed extraction voltage, 16.25 kV; lens voltage, 10.0 kV) spectra further expanded the detectable polymers up to 27-mers. Litchi seed condensed tannins were A-type procyanidins polymer with as high as 27-mers. In the present study, reflectron modes coupled with linear modes was discussed as a potential method of MALDI-TOF MS in characterization of condensed tannins.教育部新世纪优秀人才支持计划(No.NCET-07-0725); 国家自然科学基金(No.31070522)资助项

Characterization of Condensed Tannins from Litchi Seed by Reflectron Modes and Linear Modes of MALDI-Tof MS

利用不同模式的基质辅助激光解吸电离飞行时间质谱(MAldI-TOf MS)分析荔枝果核缩合单宁.在反射模式(rEflECTrOn MOdES)下,加速电压20.0 kV,反射电压23.0 kV,延时取出电压16.32 kV,聚焦电压9.45 kV,获得缩合单宁的准确结构单元组成和连接方式信息,其为三聚体至十八聚体组成的A型原花青定多聚物.在线性模式(lInEAr MOdES)下,加速电压20.0 kV,延时取出电压16.25 kV,聚焦电压10.0 kV,检测到十九聚体至二十七聚体的缩合单宁信号,其更全面获取缩合单宁聚合度的分布信息.综合两种模式,荔枝果核缩合单宁是由三聚体至二十七聚体分布的A型原花青定多聚物.探讨了一种联合反射模式与线性模式对植物单宁结构准确分析的基质辅助激光解吸电离飞行时间质谱方法.Condensed tannins from litchi seed were analyzed using reflectron modes and linear modes of matrix-assisted laser desorption/ionization time-of-flight mass spectrometry(MALDI-Tof MS).The reflectron modes(accelerating voltage,20.0 kV;reflectron voltage,23.0 kV;delayed extraction voltage,16.32 kV;lens voltage,9.45 kV) spectra obtained clear information on basic unit,interflavan linkage and polymerization degree extended from 3-mers to 18-mers.The linear modes(accelerating voltage,20.0 kV;delayed extraction voltage,16.25 kV;lens voltage,10.0 kV) spectra further expanded the detectable polymers up to 27-mers.Litchi seed condensed tannins were A-type procyanidins polymer with as high as 27-mers.In the present study,reflectron modes coupled with linear modes was discussed as a potential method of MALDI-Tof MS in characterization of condensed tannins.教育部新世纪优秀人才支持计划(No.NCET-07-0725);国家自然科学基金(No.31070522)资助项

Absorption and enrichment of heavy metals by Casuarina equisetifolia of different stand ages in a coastal zone

为研究不同林龄木麻黄对重金属的吸收与富集作用,用ICP-MS测定了福建东山县国有防护林场10、16、20、30年生木麻黄小枝、细根、凋落物及林地土壤中的5种重金属(Cr、Cu、zn、Cd和Pb)含量。结果表明,木麻黄对不同重金属的吸收能力不同,从高到低为zn>Cr>Pb>Cu>Cd;木麻黄细根中Cr和Cu、Pb,fE和Cu,zn和Cd具有明显的协同作用;各林龄木麻黄对重金属均具有一定的耐性,对Cu、zn、Cd、Pb有很好的富集作用;20年生木麻黄的重金属年积累量最高;说明木麻黄对重金属的净化作用具有极大的潜力,20年生木麻黄作用最为明显。To assess the absorption and enrichment of heavy metals by Casuarina equisetifolia,the concentrations of heavy metals including Cr,Cu,Zn,Cd and Pb in branchlet,fine root,litter and soil of C.equisetifolia forests at four ages( 10,16,20,30) were determined.The results showed that the enrichment degree of the heavy metals in C.equisetifolia ranked as Zn > Cr> Pb > Cu > Cd.Correlation analysis showed that Cr and Cu,Pb,Fe and Cu,Zn and Cd had significant synergies in the fine roots of C.equisetifolia.C.equisetifolia had a higher capability of absorbing and accumulating heavy metals.Annual accumulation of heavy metals was highest in20 years old C.equisetifolia.Our results indicate that C.equisetifolia has a great potential for reducing the pollution of heavy metals,especially for the 20 years old forest.国家自然科学基金项目(41176090); 国家科技支撑项目(2009BADB2B0302)资

凝胶纺壳聚糖分散碳纳米管/聚丙烯腈纤维的研究

多壁碳纳米管(MWNTs)通过壳聚糖衍生物处理后与超高分子量聚丙烯腈进行复合,将得到的复合材料通过凝胶纺丝法制备出不同复合比例的MWNTs/聚丙烯腈纤维.将不同纺丝方法以及不同比例MWNTs对拉伸强度、模量、取向度、结晶结构的影响进行比较研究,同时通过电镜观察MWNTs的分散状况.结果表明:相比于湿法纺丝,通过凝胶纺丝法制备的复合纤维,MWNTs取向更好,分散更为均匀,纤维拉伸强度、模量都得到显著提高.对比未加MWNTs的对照样,在这个体系中加入质量分数为0.5%的MWNTs复合时,拉伸强度提高37%,弹性模量提高11.68%,并且声速取向度维持在相当高的水平(92.5%)

滨海沙地主要造林树种纯林与混交林叶片热值特征

对福建东南沿海防护林4种主要树种纯林及混交林共8个林分类型成熟和衰老叶片的热值进行了研究。结果表明,在4种纯林中,厚荚相思叶片中热值最高,湿地松次之,都高于木麻黄和桉树;木麻黄纯林、木麻黄-厚荚相思混交林、木麻黄-湿地松混交林中木麻黄小枝热值差别不显著,都高于与桉树混交的木麻黄小枝;厚荚相思纯林和混交林成熟叶及衰老叶热值都高于湿地松和桉树;在所有的林分类型中,衰老叶中的热值都高于成熟叶或差别不显著。国家“十一五”科技支撑计划项目(2006BAD03A14-01);; 福建省重大科技专项(2006NZ0001-2);; 福建省森林培育与林产品加工利用重点实验室资助项

控制肝脏组织发育、再生重塑与大小的关键蛋白质机器

肝脏损伤、功能衰竭及肝癌等疾病是我国重大健康问题,它们的发生发展与肝脏再生重塑及大小调控异常密切相关。针对肝脏发育、再生及大小控制机理的基础研究对于解决上述重大肝脏疾病的临床需求具有重要意义。前期研究发现Hippo信号通路在调控细胞增殖及分化、干细胞命运等方面起着关键作用,而Hippo通路的失调可导致肝脏等器官发育和大小异常,严重影响受损组织再生与重塑,或导致肿瘤迅速发生。本项目拟以肝脏为研究对象,聚焦Hippo相关信号网络如何感知器官大小并适时调控细胞生长、分化与死亡以实现器官发育、再生重塑和器官大小控制这一关键科学问题,整合基础、临床、药学领域的先进研究技术,拟通过基因编辑、内胚层干细胞肝向分化、肝细胞移植和肝脏重建、肝脏损伤修复等模型、临床病理分析、蛋白结构解析和靶向药物设计等方法,深入探讨该通路失控导致肝脏发育异常、再生重塑障碍、癌症发生的致病机理,并提出靶向干预新策略。控制肝脏组织发育、再生重塑与大小的关键蛋白质机器(2017YFA0504500

木麻黄低效林不同发育阶段小枝单宁含量

为了探讨环境条件对单宁生产的影响,该文选择木麻黄低效林三个不同发育阶段的小枝进行单宁含量的测定。结果表明:在不同的发育阶段,总酚含量表现为幼嫩>成熟>衰老小枝,缩合单宁中除纤维素结合缩合单宁外,均表现为随小枝成熟而下降,随小枝衰老而升高;在低效林中的各单宁组分均高于对照。对环境条件比较敏感的幼嫩小枝和受环境胁迫较重的低效林比对照小枝中单宁含量高,表明不良的环境条件促进了单宁的形成。国家“十一五”科技支撑计划项目(2006BAD03A14-01);; 福建省重大科技专项(2006NZ0001-2);; 福建省森林培育与林产品加工利用重点实验室资助项