~(27,28)P+~(28)Si总反应截面增强及可能相关的机制

测量了27,28P和相应同中子异位素在28Si靶上的中能反应截面.测得N=12和13同中子异位素的反应截面在Z=15处突然增大.对Z≤14同中子异位素和28P的实验数据结果可以用改进的光学极限近似的Glauber理论很好地描述.28P的反应截面能够用扩大核芯以改进的Glauber理论来解释.但是,用改进光学极限和少体近似的Glauber理论却低估了27P的实验数据.理论分析表明,扩大的核芯加质子晕可能是响应27P+28Si反应截面增强的机制.

~(19)F+~(27)Al深部非弹性碰撞产物的角分布

完成了19F+27Al深部非弹性碰撞产物的角分布测量.初步分析了反应产物B,C,N,O,F,Ne,Na,Mg和Al的实验室系角分布,展现出深部非弹性反应机制的特点,显示了反应系统随时间的演化过程.

~(27)Al+~(27)Al重离子耗散碰撞中能量自关联函数的分析

测量了2 7Al+ 2 7Al耗散反应产物的激发函数 ,束流2 7Al8+的入射能量从1 1 4MeV到 1 2 7MeV变化 ,能量步长为 2 0 0keV .探测角度覆盖了实验室系1 0°— 57°的连续区域 .用不同的理论模型分析了耗散产物的能量自关联函数 .结果表明 ,反应所形成的中间双核系统的阻尼相干转动造成了激发函数中不可平滑的涨落结构 ,相干转动的阻尼来自量子混沌运动

~(27)Al+~(27)Al耗散反应截面涨落的角度关联测量

在2 7Al+ 2 7Al(Elab≈ 1 2 0MeV)耗散反应激发函数涨落的实验研究中 ,首次在较大的角度范围内获得截面涨落的角度关联系数和角度关联函数 .实验结果表明 ,角度关联函数的形状呈现明显的非对称性 ,角度相干宽度至少为 4 0°;截面涨落在前后角区表现出明显不同的角度相关性 .

25MeV/u ~(40)Ar+~(115)In,~(58)Ni,~(27)Al反应中前中角区碎片角分布和元素Z分布

测量了 ２５ＭｅＶ／ｕ４０　Ａｒ＋１１５　Ｉｎ，５８　Ｎｉ，２７　Ａ１反应前中角区出射碎片的角分布和 元素 Ｚ分布．用改进的量子分子动力学（ＭＱＭＤ）模型研究了碎片的角分布和 Ｚ 分布．理论计算值和实验值整体上符合得很好，但在前角区，ＭＱＭＤ模型低估 了碎片的产额，在中角区对于Ｚ接近弹核的碎片，理论计算值比实验值偏高．碎 片产物的角分布和Ｚ分布还与统计蒸发模型ＧＥＭＩＮＩ进行了比较，结果表明，在 前角区平衡蒸发成份所占的比例很小，中角区所占的比例有所增加，但仍然是较 小的比例．同时发现平衡蒸发成份随着出射碎片核电荷数Ｚ的减小而逐渐减 少．

Cross-correlation of excitation functions for different fragments and different scattering angles in Al-27(F-19, x)y reactions

Excitation functions have been measured for different projectile-like fragments produced in Al-27(F-19,x)y reactions at incident energies from 110.25 to 118.75 MeV in 250 keV steps. Strong cross section fluctuations of the excitation functions are observed. The cross- correlation coefficients of the excitation functions for different atomic number Z and for different scattering angle theta(cm) have been deduced. These coefficients are much larger than the statistical theoretical calculated ones. This indicates that there are strong correlations between different exit channels in the dissipative heavy ion Collision of Al-27(F-19,x)y.

Largely deformed dinuclear system formed in F-19+Al-27 dissipative collision

Excitation functions are measured for different charge products of the F-19+(27) Al reaction in the laboratory energy range 110.25-118.75MeV in steps of 250keV at theta(lab) = 57 degrees, 31 degrees and -29 degrees. The coherence rotation angular velocities of the intermediate dinuclear systems formed in the reaction are extracted from the cross section energy autocorrelation functions. Compared the angular velocity extracted from the experimental data with the ones deduced from the sticking limit, it is indicated that a larger deformation of the intermediate dinuclear system exists.

Rotation and deformation of the dinuclear system formed in dissipative reaction of F-19+Al-27

Excitation functions of the reaction products B, C, N, O, F and Ne emitted from the dissipative reaction of (19) F+(27) Al have been measured at incident energies from 110.25MeV to 118.75MeV in steps of 250keV. The moments of inertia of the intermediate dinuclear system formed in the reaction are extracted from the energy autocorrelation functions of the products. Comparing the moment of inertia extracted from the experimental data with the calculated one by using the sticking limit, it indicates that the formed dinuclear system has a large deformation in the reaction process.

Non-reproducibility of the cross sections of the products induced from dissipative reaction of F-19+Al-27

The differential cross sections of the dissipative products B, Q N, O, F, Ne, Na and Mg induced from the reactions of F-19+Al-27 at two incident energies have been measured at the HI-13 tandem accelerator, Beijing. In the case of a fixed beam incident energy 114MeV or 118.75MeV respectively, identical reaction system and the same detection system, 20 target points in steps of 2mm on(.)a 10mmx50mm rectangular Al foil have been bombarded. The experimental results indicate that the probability distribution of the cross sections is much wider than a standard Gaussian distribution. This non-reproducibility of the cross sections can't be interpreted by the statistical property of a finite count rate.

Study on conical columns for semi-preparative liquid chromatography

The dynamic flow profiles and column efficiencies in conically shaped semi-preparative liquid chromatographic columns (inlet ID larger than outlet ID) with two different conical angles (7degrees and 15degrees) were studied. The dynamic flow profiles were studied by an on-column visualization method. Conical columns were compared with cylindrical column of the same length and internal volume. The results showed that the flow profile of a sample band in the conical column of 7degrees (50 mm x 17 mm --> 11 mm ID) was parabolic in shape. The sample band migrated slower in the wall region than in the central region, as in the cylindrical column (50 mm x 14 mm ID). However, the sample band in the conical column of 15degrees (50 mm x 20 mm --> 7 mm ID) migrated slower in the central region than in the wall region, resulting in a reverse parabolic flow profile, in contrast to that in cylindrical column. This indicated that a flat flow profile might be realized in a conical column with a conical angle between 7degrees and 15degrees. The conical column of 15degrees had the highest column efficiency among the three columns under the same conditions. Compared with the cylindrical column packed with identical packing material, the conical column of 15degrees had 22%-45% higher column efficiency and 11%-27% higher peak height.

Identification of 27 Porphyra lines (Rhodophyta) by DNA fingerprinting and molecular markers

Twenty-seven Porphyra lines, including lines widely used in China, wild lines and lines introduced to China from abroad in recent years, were screened by random amplified polymorphic DNA (RAPD) technique with 120 operon primers. From the generated RAPD products, 11 bands that showed stable and repeatable RAPD patterns amplified by OPC-04, OPJ-18 and OPX-06, respectively were scored and used to develop the DNA fingerprints of the 27 Porphyra lines. Moreover, the DNA fingerprinting patterns were converted into computer language expressed with two digitals, 1 and 0, which represented the presence (numbered as 1) or absence (numbered as 0) of the corresponding band, respectively. Based on the above results, computerized DNA fingerprints were constructed in which each of the 27 Porphyra lines has its unique fingerprinting pattern and can be easily distinguished from others. Software named PGI (Porphyra germplasm identification) was designed for identification of the 27 Porphyra lines. In addition, seven specific RAPD markers from seven Porphyra lines were identified and two of them were successfully converted into SCAR (sequence characterized amplification region) markers. The developed DNA fingerprinting and specific molecular markers provide useful ways for the identification, classification and resource protection of the Porphyra lines.

桑沟湾贝藻养殖区附着生物生态效应研究

附着生物又称污损生物，是附生在海洋设施和生物体表面的动物、植物和微生物等生物的总称（Azis et al., 2001）。附生在养殖器材和生物体表面的数量巨大的附着生物，对贝类养殖和海湾生态系统内的物质和营养盐循环等多个方面产生影响。本研究以北方重要的养殖海湾----桑沟湾为研究对象，对贝藻养殖区附着生物的群落演替及其生态效应进行了研究。主要研究结果如下： ① 2007年5月至2008年5月，采用挂网的方法对桑沟湾栉孔扇贝和海带混养区的附着生物的季节变化进行了研究。结果显示挂网上的附着生物具有显著的季节变化特征，网片上的附着生物湿重与水温的变化相一致，生物量为3~1210 g•m-2。2月份附着生物的生物量最低，8月份最高。2007年9月至11月，对栉孔扇贝养殖笼上和贝壳上的附着生物种类和数量进行了研究。结果显示9月份养殖笼上附着生物的湿重约为1.94 kg，10月份降至0.99 kg，11月份又稍有增加，为1.03 kg。扇贝壳上的附着生物变化趋势与养殖笼上的相同，9~11月份壳上附着生物的数量约0.49~2.09 g。扇贝养殖笼上可鉴定的大型附着生物约23种，包括藻类、海鞘类、苔藓虫类、环节动物、腔肠动物、软体动物、甲壳动物和海绵动物等。玻璃海鞘、柄海鞘、紫贻贝和苔藓虫等是附着生物群落中的优势种。 ② 通过在栉孔扇贝和虾夷扇贝上壳上添加不同重量的“模拟附着生物”（速凝水泥）的方法，研究了贝壳上附着生物的重量对这两种扇贝生长和存活的影响。结果显示水泥重量是上壳重0.5-3倍的各组实验组扇贝的生长和存活与对照组（未添加水泥的扇贝）之间没有显著差异。说明贝壳上附着生物重量为上壳的3倍重时，也不会显著影响扇贝生长存活。9-11月份贝壳上的自然附着生物的重量约为1.47-2.09 g，为上壳重的28.16 (±38.6)%—31.29 ± (31.63)%。因此，贝壳上附着的生物重量不太可能对扇贝的生长存活造成显著的负面影响。 ③ 在桑沟湾现场测定了玻璃海鞘和柄海鞘的生物沉积速率。9月份（水温约24℃）玻璃海鞘和柄海鞘的生物沉积速率分别为32.14和90.06 mg•ind-1•d-1或（858.99 和467.76 mg•gdw-1•d-1），据此计算，养殖笼上的两种海鞘的生物沉积速率约为84.29 mg•m-2•d-1。海区的自然沉积速率为41.49 mg•m-2•d-1；玻璃海鞘和柄海鞘沉积物中有机质含量分别为14.34%和13.77%，对照组海区自然的有机质含量为14.36%；以上三者有机碳的含量分别为24.72%，23.74%和24.76%；氮的含量分别为0.27%和0.25%，自然沉积物中的氮含量为0.30%。9月份扇贝养殖笼上附着的海鞘将产生2588.16吨的沉积物，即向底部沉积363.77吨的有机物、6.99吨的氮和1.79吨的磷。 ④ 通过测定扇贝养殖笼上优势种附着生物--玻璃海鞘、柄海鞘和贻贝的摄食、呼吸和排泄，研究了这些优势种类对贝类养殖和海湾环境的影响。9月份（水温约24.5℃）玻璃海鞘和柄海鞘对颗粒有机物（POM）的摄食率分别为14.30 和17.01 mg• h-1•ind-1。根据实验结果计算这两种海鞘摄取的颗粒有机物相当于312个扇贝的摄取量，大于笼内养殖的扇贝的摄取量；玻璃海鞘和柄海鞘的耗氧率分别约为0.32和0.18 mg•h-1•ind-1，养殖笼上的这两种海鞘消耗的溶解氧约等于75个扇贝消耗的溶解氧。栉孔扇贝、玻璃海鞘、柄海鞘和贻贝的排氨率分别为33.66 ±11.34，117.90±23.46，35.91±6.22，28.08±3.41 ug NH4-N•gdw-1•h-1。以此估算，9月份玻璃海鞘、柄海鞘和贻贝每天排泄的氨氮约为654.08 kg，相当于16467吨栉孔扇贝（鲜重）排泄的氨氮。海鞘和贻贝排泄的氨氮可提供浮游植物等所需的2.75%的氮，可以提供1204吨海带的生长所需的氮。 ⑤ 一个养殖笼内的栉孔扇贝和全部附着生物（Scallop Culture Unit, SCU）在夏季（6-9月）对颗粒有机物的摄食速率约为43.13-98.94 mg/h，平均74.05 mg/h，期间桑沟湾养殖的栉孔扇贝及附着生物摄取的POM约为1279.58吨；同期，SCU对氨氮和磷（PO4-P）的排泄速率分别为125.59-1432.23 μmol•h-1和76.2-252.89μmol•h-1，期间桑沟湾养殖扇贝及附着生物排泄的氮磷分别为211.09 吨和83.79 吨。一串牡蛎及吊绳和牡蛎壳上的附着生物（Oyster Culture Unit, OCU），夏季摄食率为5-41.43μmol•h-1，耗氧率为16.54-41.76μmol•h-1，对氨氮和磷（PO4-P）的排泄速率分别为35.56-489.34μmol•h-1 和9.92-16.68μmol•h-1。以此估算，夏季OCU可摄取POM535.68吨，消耗溶解氧955.58吨，排泄氮磷分别为62.37 吨和15.50 吨。

PRINCIPAIS INDICADORES: AGRÍCOLAS, v. 3, n. 27, 2010.

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PRINCIPAIS INDICADORES: LEITE E DERIVADOS, v. 3, n. 27, 2010.

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PRINCIPAIS INDICADORES: MACROECONÔMICOS, v. 3, n. 27, 2010.

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