Photosynthetic capacity of three common species of macroalgae and the application in coral aquarium

利用水下饱和脉冲调制叶绿素荧光仪(dIVIng-PAM)测定了珊瑚养殖水处理中3种常见大型海藻石莼(ulVA lACTuCA)、条浒苔(EnTErOMOrPHA ClATHrATA)和羽状蕨藻(CAulErPA MEXICAnA)光能转化效率(fV/fM),快速光曲线(rlC)相关参数和非光化学淬灭(nPQ)。结果表明:石莼和条浒苔的fV/fM分别为0.808±0.004和0.816±0.009,显著高于羽状蕨藻。最大相对电子传递速率rETrMAX(17.52±2.92和19.59±4.43μMOl E·M-2·S-1)、半饱和光强Ik(53.41±8.18和59.71±13.52μMOl PHOTOnS·M-2·S-1)也明显高于羽状蕨藻(rETrMAX和Ik分别为13.72±5.41μMOl E·M-2·S-1和32.67±14.06μMOl PHOTOnS·M-2·S-1),表明石莼和条浒苔有着比羽状蕨藻更高的光合能力和对强光的耐受能力,光保护能力更强;羽状蕨藻较高的rlC初始斜率α表明其在弱光下拥有更强的光捕获能力,弱光下光合效率更高;随光照的增强(0~373μMOl PHOTOnS·M-2·S-1),羽状蕨藻nPQ的增幅有限(0~0.2),最大值仅为条浒苔和石莼的38.1%和62.5%,表明这种藻类更容易受到强光的抑制。因此,在珊瑚养殖的水处理中,可以根据不同的光照选择适宜的藻种或藻种组合并根据光梯度进行布局,反之也可以根据藻种来选择合适的光源,以达到最佳的处理效率。This study investigated the difference of photosynthetic capacity in three macroalgae species( Ulva lactuca,Enteromorpha clathrata,and Caulerpa mexicana) commonly used for nutrient removal in coral aquariums.The photochemical efficiency( Fv/Fm),parameters relevant to rapid light curve( RLC) and non-photochemical quenching( NPQ) in the macroalgae were measured by underwater saturation pulse modulated chlorophyll fluorometer( Diving-PAM).The results showed that Fv/Fmwas 0.808 ± 0.004 for U.lactuca and 0.816 ± 0.009 for E.clathrata,which were higher than that for C.mexicana.Higher maximum relative electron transfer rates( rETRmax)( 17.52 ±2.92 and 19.59 ±4.43 μmol e·m- 2·s- 1) and half-starved value of light intensities( Ik)( 53.41 ±8.18 and 59.71 ±13.52 μmol photons·m- 2·s- 1) were observed in U.lactuca and E.clathrata than that in C.mexicana( 13.72 ± 5.41 μmol e·m- 2·s- 1for rETRmaxand 32.67 ± 14.06 μmol photons·m- 2·s- 1for Ik),indicating that U.lactuca and E.clathrata have stronger photosynthetic capacities,photo-protection capacities and tolerance to higher intense light than C.mexicana.A significantly lower RLC initial slope α in C.mexicana implied that this algal species has a higher photosynthetic capacity under weak light condition.With increasing the light intensity( 0- 373 μmol photons·m- 2·s- 1),however,C.mexicana had a limited increase of NPQ( 0- 0.2),the maximum of which was equivalent to 38.1% of that in U.lactuca and 62.5% of that in E.clathrata.These results indicate that the photosynthesis of E.clathrata may be more easily limited by intense light.Our study suggests that the selection of algal species for nutrient removal in a coral aquarium should be adapted to the light intensity.Single species or the combination of different species of macroalgae can be selected according to the illumination of the coral aquarium in order to maximize the efficiency of nutrient removal.国家海洋局第三海洋研究所基本科研业务项目(海三科2011033); 厦门海洋研究开发院共建项目; 海洋公益性行业科研项目(201105012)资

Critical tidal level for Kandelia candel forestation in strong tidal range area

以国内最大潮差值的乐清湾西门岛海域为研究地点,选定黄零为1.96、1.66、1.35和1.03M4个高程断面,对各高程上1年生和3年生秋茄(kAndElIA CAndEl)幼苗的成活率、生长指标以及污损生物(藤壶)等因子进行了统计分析.结果表明:不同高程内,1年生和3年生秋茄幼苗的生长存在显著性差异;秋茄幼林植株上附生有白脊藤壶(bAlAnuS AlbICOSTATuS)和纹藤壶(bAlAnuS AMPHITrITE AMPHITrITE)2种藤壶,其中优势种白脊藤壶在黄零1.35M的高程对秋茄的污损最为严重.西门岛秋茄的宜林线为黄零1.66M,即不低于当地平均海平面以上1.29M、每个潮水周期平均淹水时间小于3.65H的潮滩.藤壶、强潮和极端天气是该地区秋茄宜林线明显高于当地平均海平面的主要原因.Taking Ximen island of Yueqing bay,the biggest tidal range area among the coasts of China,as study site,an investigation was made on the survival rate,growth characteristics,and attached barnacles of 1-and 3-year old Kandelia candel seedlings at the elevations 1.96,1.66,1.35,and 1.03 m above the zero tidal level of Yellow Sea.Significant differences were observed in the survival rate and growth situation of the seedlings among the elevations.There were two barnacle species,Balanus albicostatus and Balanus amphitrite amphitrite,and B.albicostatus was the major species which attached K.candel most seriously at elevation 1.35 m.The critical tidal level for K.candel in the site was 1.66 m above the zero tidal level,i.e.,at least 1.29 m higher than the local mean sea level,and the flooding time per tide cycle being less than 3.65 h.Barnacle,strong tide,and extreme weather event were the main reasons for the higher critical tidal level.海洋公益性行业科研专项(200805072);浙江省科技计划项目(2008F1009);温州市科技计划项目(S20060037);浙江省科技厅创新团队建设与人才培养项目(2009F20009)资

蜗牛酶与木霉纤维素酶协同用于皇竹草酶解及发酵乙醇的研究

本文以蜗牛酶与木霉纤维素酶为纤维素酶来源,混合后用于汽爆皇竹草水解并发酵乙醇。结果表明,蜗牛酶与木霉纤维素酶混合用于纤维素酶解时,混合比例以3:1为最优,这时混合酶的滤纸酶活比混合前两种酶的滤纸酶活之和要高出45%,混合酶比蜗牛酶与木霉纤维素酶单独的葡萄糖得率分别高出114.3%和25%;但混合酶用于纤维素同步糖化发酵乙醇时,混合比例以1:3为最优,这时混合酶比蜗牛酶与木霉纤维素酶单独的乙醇得率分别高出45%和25%

膜生物反应器在汽爆稻草秸秆酶解中的应用研究

研制了一种新型的膜生物反应器用于汽爆稻草秸秆的酶解反应,该反应器由酶解区和膜分离区两部分组成,酶解区又分为固定相(底物+酶)和流动相(缓冲液)。通过流动相将汽爆稻草秸秆酶解产生的还原糖淋洗下来,并带到膜分离区进行在线分离以除去产物抑制对酶解的影响。实验考察了酶浓度,酶解单元组成以及稀释率对汽爆稻草秸秆酶解的影响。研究结果表明最佳条件为:20FPA/g,酶解单元由4个酶解罐组成,稀释率为0.075h-1.在该条件下当酶解时间为24h时,汽爆稻草秸秆的总转化率可以达到39.5%,与传统的批次酶解所得到的18-21%的总转化率相比,提高了将近1倍。与常规的膜反应器相比,还原糖的产量从0.25g/g(..

膜生物反应器在汽爆稻草秸秆酶解中应用研究

以汽爆稻草秸秆为原料，通过将几个酶解罐串联来提高最终还原糖浓度．考察了酶浓度，酶解单元组成以及稀释率对汽爆稻草秸秆酶解的影响．结果表明，最佳条件为：20FPU／g，酶解单元由4个酶解罐组成，稀释率为0．075／h．在此条件下，酶解时间为24h时，与传统批次酶解相比，汽爆稻草秸秆总转化率从18％～21％提高到39．5％．与只有1个酶解罐的膜反应器相比，每g底物还原糖产量从0．25g提高到0．4g，最终所得还原糖的平均浓度从4．56g／L提高到27．23g／L

膜生物反应器在汽爆稻草秸秆酶解中应用研究

以汽爆稻草秸秆为原料，通过将几个酶解罐串联来提高最终还原糖浓度．考察了酶浓度，酶解单元组成以及稀释率对汽爆稻草秸秆酶解的影响．结果表明，最佳条件为：20FPU／g，酶解单元由4个酶解罐组成，稀释率为0．075／h．在此条件下，酶解时间为24h时，与传统批次酶解相比，汽爆稻草秸秆总转化率从18％～21％提高到39．5％．与只有1个酶解罐的膜反应器相比，每g底物还原糖产量从0．25g提高到0．4g，最终所得还原糖的平均浓度从4．56g／L提高到27．23g／L

膜生物反应器在汽爆稻草秸秆酶解中应用研究

以汽爆稻草秸秆为原料,通过将几个酶解罐串联来提高最终还原糖浓度.考察了酶浓度,酶解单元组成以及稀释率对汽爆稻草秸秆酶解的影响.结果表明,最佳条件为:20FPU/g,酶解单元由4个酶解罐组成,稀释率为0.075/h.在此条件下,酶解时间为24h时,与传统批次酶解相比,汽爆稻草秸秆总转化率从18%~21%提高到39.5%.与只有1个酶解罐的膜反应器相比,每g底物还原糖产量从0.25g提高到0.4g,最终所得还原糖的平均浓度从4.56g/L提高到27.23g/L

Study on Vacuum Sensitive Mechanism of Surface States Silicon by Photovoltaic Method

根据光伏方法研究的半导体表面气体分子吸附机理 ,提出了硅单晶表面态真空敏感效应的机理模型 ,解释了表面态敏感型的真空传感器的各有关观测结果 .因此可以确认 ,硅单晶表面态对真空敏感的实质原因就是由于构成大气主要成份的氮气和氧气两种元素的电子亲和势相对于硅元素 ,具有明显不同的且符号相反的差值 ,导致吸附于硅表面的 N2 、O2 分子与硅表面态之间不同转移方向的电荷转移差值可以随真空度变化所引起的A mechanism model of the sensitive effect of vacuum conditions on the surface states of silicon crystal is proposed,from study on the adsorption mechanism of gaseous molecules on the surface of semiconductor by photovoltaic method.Consequently the relative observed results from the vacuum sensors based on the surface state sensitivity are clearly explained.Thereby,it can be confirmed that the essential cause of the vacuum sensitive for the surface states of silicon is that the electron affinity potentials of nitrogen element and oxygen element,relative to of silicon element,have obviously different and sign opposite difference values.It can cause the charge transfers with different directions between N 2,O 2 molecules adsorbed on silicon surface and the surface states of silicon and their difference value varies with the change of vacuousness

去中心化自治组织：发展现状、分析框架与未来趋势

分布式自治并非一个新的概念，自然界中的自组织现象、互联网上的动态网民群体组织以及分布式人工智能等均可视作其早期表现形式。近年来，区块链技术的快速发展催生了去中心化自治组织（DAO），它是一种将组织的管理和运营规则以智能合约的形式编码在区块链上，从而在没有集中控制或第三方干预的情况下自主运行的组织形式。因此，DAO有望成为应对不确定、多样、复杂环境的一种新型有效组织。然而，DAO正处于起步阶段，理论研究尚处于空白，且难以实现大规模应用。本文首先对 DAO 的概念及特征做出清晰界定；接着首次系统地提出DAO五层分析框架，并以此为基础对典型的DAO应用案例——Aragon做了详尽分析；之后讨论DAO目前所面临的问题和下一步可能的研究方向，以期为未来研究提供有益的参考与借鉴