无人机多机协同对抗决策研究

针对多对多无人机之间的空战对抗,考虑对抗双方具有同等数量无人机的情况,利用影响图(ID)建立多无人机协同空战连续决策过程,使用贝叶斯推论对空战态势进行实时评估.根据评估结果,采用匈牙利算法完成目标的动态分配,将多无人机之间的对抗转化为动态的多个单架无人机之间的对抗,无人机在对抗中根据由双方态势所设计的决策规则进行机动决策.红蓝双方多无人机之间对抗仿真实验结果表明了所设计模型的有效性.国家自然科学基金资助项目(61673327);;航空科学基金资助项目(20160168001

安全心理学研究的最近状况及趋势

从科学技术对安全心理学的影响、事故致因与人为失误及事故预防技术等三个方面介绍了安全心理学的最近研究状况及趋势。着重分析了工程控制技术、行为控制技术、风险管理技术、宏观安全管理技术及系统措施等事故预防技术

Effects of CO2-induced seawater acidification on photosynthesis and calcification in the coralline alga Corallina pilulifera

为了探讨CO2海底封存潜在的渗漏危险对于海洋生物的可能影响,以大型钙化藻类小珊瑚藻(COrAllInA PIlulIfErA)为研究对象,在室内控光控温条件下,通过向培养海水充入CO2气体得到3种不同酸化程度的培养条件(PH 8.1、6.8和5.5),24H后比较藻体光合作用和钙化作用情况。结果显示:相对于自然海水培养条件(PH 8.1),在PH 6.8条件下培养的小珊瑚藻光合固碳速率得到了增强,而在PH 5.5条件下光合固碳速率则降低;随着酸化程度的增强,藻体的钙化固碳速率越来越低,在PH 5.5条件下甚至表现为负值[(-2.53±0.57)Mg C g-1干重H-1];藻体颗粒无机碳(PIC)和颗粒有机碳(POC)含量的比值随着酸化程度的加强而降低,这反映了酸化对光合和钙化作用的综合效应。快速光反应曲线的测定结果显示:随着酸化程度的增强,强光引起的光抑制程度越来越强;在酸化条件下,藻体的光饱和点显著降低,但PH 6.8和5.5之间没有显著差异;低光下的电子传递速率在PH 8.1和6.8之间没有显著差异,PH 5.5培养条件下显著降低;最大电子传递速率在PH 6.8时最大,在PH 5.5时最低。以上结果说明,高浓度CO2引起的海水酸化显著地影响着小珊瑚藻的光合和钙化过程,不同的酸化程度下,藻体的光合、钙化反应不同,在较强的酸化程度下(PH 5.5),藻体的光合和钙化过程都将受到强烈的抑制,这些结果为认识CO2海底封存渗漏危险对海洋钙化藻类的可能影响提供了理论参考。Increasing atmospheric CO2 is causing global public concern and seabed sequestration is one possible method of carbon reduction.However,studies on the potential risk of CO2 leakage and its possible effects on the marine environment are still very limited.To investigate such possible effects on sensitive marine organisms,coralline algae,Corallina pilulifera,were cultured under controlled conditions: 20℃,100μmol photons m-2 s-1 and a light period of 12h.Three treatments were set at acidities of pH 8.1,6.8 and 5.5,by aerating natural seawater with pure gaseous CO2.After 24 hours,photosynthesis and calcification rates of C.pilulifera cultured at different pH levels were determined.The rate of photosynthetic carbon fixation was enhanced at the pH of 6.8 and was inhibited at the pH of 5.5,compared with the algae grown in the seawater control(pH 8.1).The rate of calcified carbon fixation was depressed with decreasing pH,and even exhibited a negative value [(-2.53±0.57) mg C(g DW)-1 h-1] at pH 5.5.Additionally,with the decrease in pH,the ratio of particulate inorganic carbon(PIC) to particulate organic carbon(POC) content in the algae,measured with a vario TOC cube,decreased remarkably,which reflected the comprehensive effects of CO2-induced seawater acidification on photosynthesis and calcification.Rapid light curves of algae cultured at different pH levels,which indicated the responses of electron transport rates(ETR) in photosystem II(PS II) to irradiance,were determined by pulse amplitude modulated chlorophyll fluorescence(PAM).The results showed that the photoinhibition term(a) increased with the decrease in pH,indicating that algae grown at lower pH levels experience greater photoinhibition.The light saturation point(Ik) decreased significantly under the CO2-induced acidification conditions,though a significant difference was not found between pH of 6.8 and 5.5.The initial slope of the rapid light curve(α),reflecting the efficiency of the electron transport rate at low irradiance,was lower at pH 5.5 than at the other two levels,while there was no significant difference between pH 8.1 and 6.8 levels.The maximum relative electron transport rate(rETRmax) exhibited the highest value in algae cultured at pH 6.8 and the lowest at pH 5.5.According to these results,we concluded that CO2-induced seawater acidification noticeably affected the photosynthesis and calcification of C.pilulifera,and different degrees of acidification caused different responses of photosynthesis and calcification.At the lowest pH level(pH 5.5),both the photosynthesis and calcification of C.pilulifera were significantly inhibited.These results provide a reference for studies on the risk of CO2 leakage from seabed sequestration methods on the physiology and ecology of marine coralline algae.海洋行业公益项目(200805029和200905020-2);国家海洋局重点实验室基金(200912);近海海洋环境科学国家重点实验室(厦门大学)青年访问学者基金(MELRS1105);山东省科技发展计划项目(2009GG10005012

钯纳米粒子体系中的近场耦合与SERS效应

利用广义米氏散射理论(gEnErAlIzEd MIE)从理论上系统研究了球形钯纳米粒子二聚体的线性光学性质及其表面增强拉曼散射效应.计算表明,粒子间的近场耦合效应对粒子对的吸收、散射和消光光谱影响显著,其表面等离子体激元共振峰的位置随粒子间隔的变小而显著红移.在耦合效应和尺寸效应的共同作用下,钯纳米粒子二聚体中“热点“位的最大SErS增强因子可达到107~108,表面平均SErS增强因子可达105~106.通过对远场和近场的对比研究,发现消光谱与粒子间的近场增强谱的谱型大致相同,但消光谱的极值峰位与SErS的最大增强峰位之间存在一定的偏离,这显示了表面等离子激元共振对远场和近场的不同影响,我们对此进行了讨论.相关结果对揭示远场与近场的关联性及探索过渡金属体系中表面增强散射的电磁场增强机理有较重要的科学意义.国家自然科学基金(20703032);国家重点基础研究发展计划(2009CB930703);福建省自然科学基金(E0710028)资助项

Chemical constituents and cytotoxicity assay research in small polar substances from Vitis thunbergii var. taiwaniana

该文对小叶山葡萄地上部分化学成分进行了研究,运用硅胶柱色谱,OdS中低压柱色谱,SEPHAdEX lH-20凝胶柱色谱,分析型和制备型HPlC从小叶山葡萄60%乙醇提取物大孔树脂95%乙醇-水洗脱部位分离得到12个化合物,利用高分辨质谱,核磁共振等波谱手段鉴定其结构分别为:(1)bETulInIC ACId,(2)2,2,2'-bIS(4-HydrOXyPHEnyl)PrOPAnE bIS(2,3-EPOXyPrOPyl)ETHEr,(3)ErIOdICTyOl,(4)TrAnS-ε-VInIfErIn,(5)(+)-CIS-ε-VInIfErIn,(6)kObOPHEnOl A,(7)AMPElOPSIn A,(8)nEPAlEnHEnOl,(9)CIS-MIyAbEnOl C,(10)CIS-VITISIn b,(11)CIS-gnETIn H和(12)(+)-HOPEAPHEnOl。化合物2,5,6,8,9,10,11均为首次从为葡萄属中分离得到的化合物,化合物3,7,12为首次从小叶山葡萄中分离得到的化合物。在作用浓度为50μMOl·l-1下,化合物6,7和11对MCf-7(乳腺癌细胞株)具有较明显的体外生长抑制作用,其抑制率分别为66.58%,57.16%,52.84%。This article studied the chemical constituents from the aerial part of Vitis thunbergii var.taiwaniana.The 60% ethanol extract was eluted with 95% ethanol though HP-20 macroporous adsorption resin column.12 compounds,including( 1) betulinic acid,( 2) 2,2,2'-bis( 4-hydroxyphenyl) propane bis( 2,3-epoxypropyl) ether,( 3) eriodictyol,( 4) trans-ε-viniferin,( 5)( +)-cis-ε-viniferin,( 6) kobophenol A,( 7) ampelopsin A,( 8) nepalensinol B,( 9) cis-miyabenol C,( 10) cis-vitisin B,( 11) cis-gnetin H and( 12)( +)-hopeaphenol,were separated by using normal phase silica gel,ODS,Sephdadex LH-20 column chromatographies and semi-preparative or preparative HPLC.Compounds 2,5,6,8,9,10,11 were separated from the genus Vitis for the first time and compounds 3,7,12 were separated from Vitis thunbergii var.taiwaniana for the first time.At a concentration of 50 μmol·L-1,compound6,7 and 11 showed strong cytotoxicity against MCF-7 cell lines with the inhibition rate of 66.58%,57.16%,52.84%,respectively.国家自然科学基金青年基金项目(81202419

Preparation and Electrochemical Lithium Intercalation Performance of Segmented Carbon Nanofibers

以泡沫镍为催化剂 ,在 6 0 0和 70 0℃下 ,以CVD法热解乙炔气体制备大量的纳米碳纤维 .随着制备温度增加 ,纳米碳纤维直径变小 ,竹节状含量减少 ,d0 0 2 值减小 ,微晶片层平面Lc 和La 值增大 ,碳材料的可逆容量则下降 .分别用透射电镜、X射线衍射和拉曼光谱观察和测定了纳米碳纤维的形貌、微结构 ,发现在不同条件下生长的纳米碳纤维有不同的形貌和结构 .对纳米碳纤维的电化学嵌锂性能的研究表明 ,纳米碳纤维的结构对其电化学嵌锂容量和充放电循环寿命起重要影响 ,制备温度越低 ,纳米碳纤维的石墨化程度越差 ,可逆嵌锂容量相应要高一些Segmented carbon nanofibers were prepared by pyrolysis of acetylene on foam Ni at 600 and 700℃ in a fixed bed flowed-reactor. The morphology, microstructure and lithium insertion properties of these carbon nanofibers were investigated by TEM, XRD, Raman and electrochemical methods. Through TEM observations, it was found that this kind of carbon nanofibers was composed of lens-like segments with nearly equal separation stacking along the nanofiber axis. When the reaction temperature was 600℃, segmented carbon nanofibers were the major production. However, when the reaction temperature increased to 700 ℃, the content of segmented carbon filaments decreased and their diameter became smaller. The crystallite size d 002 and L c were determined by the 002 carbon Bragg peak of XRD patterns using the Bragg and Scherrer formulas. The intensity ratios of the 1350 cm -1 line and the 1580 cm -1 line (R=I D/I G) was used to evaluate the L a value, which was inversely proportional to the effective crystallite size in the direction of the graphite plane (L a). With the reaction temperature increased, the d 002 value decreased, L a and L c values increased, which indicated the degree of crystallinity increased. Segmented carbon nanofibers were used as positive electrodes of C/Li cells. The first charge capacities of C/Li cells were 480 and 300 mAh/g for samples produced at 600 and 700℃, respectively. The samples at 600℃ showed capacities higher than the theoretical value of graphite, which was attributed to accommodation of more lithium at the edge of graphene layers and on the surface of graphene layers according to the mechanisms of lithium insertion in carbons prepared by low-temperature pyrolysis of hydrocarbons. As confirmed by the XRD and Raman spectra, the samples at 700℃ had larger L a and L c, which led to the capacity decreasing.国家自然科学基金 (6 0 2 710 0 9);; 浙江省自然科学基金 (5 0 110 9,2 0 0 0 5 3)资助项

Raman and AFM Characterization of Au and Cu Nanorod and Nanowire Arrays

通过电化学氧化法制备具有不同孔径氧化铝模板 ,利用交流电镀的方法在模板中沉积金属 ,再用酸溶解模板可以得到相应尺度的金属纳米线或纳米棒的阵列 .本文利用原子力显微镜和表面增强拉曼技术分别表征了金和铜两种金属纳米线阵列 .研究结果表明 ,作为探针分子的硫氰(SCN )在金属纳米线上的碳氮三键的振动频率随纳米线直径的增大而蓝移 .这一现象可能是因为尺寸效应对纳米线的费米能级造成影响 ,使不同直径的金属纳米线电子结构存在微小的差别 .Recently metal nanowires (nanorods) have aroused tremendous interest because of their novel properties and potential applications in wide fields [1] . Many two?dimensional nanowire arrays of semiconductors and metals with different diameter and length have been made by using template synthesis method. To characterize the novel optical, electronic and magnetic properties of these materials, UV?Vis and fluorescence spectroscopies are two of the most wildly used methods [2, 3] . Raman spectroscopy has, however, only been applied to the characterizing of semiconductor nanowires and carbon nanotubes [4,5] . Important and meaningful information can be obtained in these cases, as some forbidden Raman modes in the bulk materials become Raman active [4, 5] . Raman spectroscopy is apparently not suitable to study metal nanowires since it can only detect the mechanical vibration bands located in the extremely low frequency region. Consequently, an alternative way has to be established to study the metal nano?wires (?rods) with Raman spectroscopy. In the present work, we have taken the probe molecule strategy and used surface?enhanced Raman spectroscopy (SERS) to characterize metal nanorods (nanowires). It is well known that for a molecule which interacts strongly with a surface, its vibrational band frequency and shape are very sensitive to the electronic property, the chemical environment and the morphology of the surface. Hence Raman spectroscopy has long been used to analyze the atomic structures and the electronic properties of the surface indirectly through assessing carefully the spectral changes of the adsorbate known as a probe molecule. On that account, it is of great interest to diagnose the electronic structures of the metal nanorods with the vibrational spectrum of a probe molecule. We have examined the changes in the electronic properties of the nanorods through analyzing the spectral changes of the probe molecule. For this purpose a typical SERS molecule of SCN - was employed. The nanorod arrays of Au and Cu with different diameter from about 15 nm to 130 nm were fabricated electrochemically by means of the anodic aluminum oxide (AAO) templates. To partially expose metal nanowires with various lengths, the AAO template was chemically etched off to a certain extent by an aqueous solution of phosphoric acid or sodium hydroxide as shown in Fig. 1. After the template was etched off, the nanowires can be characterized by TEM, see Fig. 2. The tapping mode AFM image was obtained on a scanning probe microscope (Nanoscope IIIa). SERS measurements were performed on a confocal microprobe Raman system (LabRam I).作者联系地址：厦门大学固体表面物理化学国家重点实验室!化学系福建厦门361005,厦门大学固体表面物理化学国家重点实验室!化学系福建厦门361005,南京师范大学化学系!江苏南京,210097,厦门大学固体表面物理化学国家重点实验室!化学系福建厦门361005,厦门大学固体表面物理化学国家重点实验室!Author's Address: State Key Lab.for Phys.Chem.of Solid Surf.,Xiamen Univ.,Xiamen 361005, China; 1 Dept. of Chem., Nanjing Norm

Preparation and electrochemical lithium intercalation performance of segmented carbon nanofibers

Segmented carbon nanofibers were prepared by pyrolysis of acetylene on foam Ni at 600 and 700degreesC in a fixed bed flowed-reactor. The morphology, microstructure and lithium insertion properties of these carbon nanofibers were investigated by TEM, XRD, Raman and electrochemical methods. Through TEM observations, it was found that this kind of carbon nanofibers was composed of lens-like segments with nearly equal separation stacking along the nanofiber axis. When the reaction temperature was 600degreesC, segmented carbon nanofibers were the major production. However, when the reaction temperature increased to 700degreesC, the content of segmented carbon filaments decreased and their diameter became smaller. The crystallite size d(002) and L-c were determined by the 002 carbon Bragg peak of XRD patterns using the Bragg and Scherrer formulas. The intensity ratios of the 1350 cm(-1) line and the 1580 cm(-1) line (R =I-D/I-G) was used to evaluate the L-a value, which was inversely proportional to the effective crystallite size in the direction of the graphite plane (L-a). With the reaction temperature increased, the d(002) value decreased, L-a and L-c values increased, which indicated the degree of crystallinity increased. Segmented carbon nanofibers were used as positive electrodes of C/Li cells. The first charge capacities of C/Li cells were 480 and 300 mAh/g for samples produced at 600 and 700degreesC, respectively. The samples at 600degreesC showed capacities higher than the theoretical value of graphite, which was attributed to accommodation of more. lithium at the edge of graphene layers and on the surface of graphene layers according to the mechanisms of lithium insertion in carbons prepared by low-temperature pyrolysis of hydrocarbons. As confirmed by the XRD and Raman spectra, the samples at 700degreesC had larger L-a and L-c, which led to the capacity decreasing