A STUDY ON 2E SPECTRA OF BIPHENYL DERIVATIVES

A study of doubly charged ion mass spectra (2E spectra), the substituents effect and the target gas pressure deppendence of biphenyl derivitives was presented in this work. The decomposition of doubly charged ion formed in the ion source is dominant by the losses of H, C2H2, C2H4 and HR(R represents substituent). [C12H8]2+, [C12H6]2+ and [C10H6]2+ among others are the most stable product ions. The substituents effect is Various in different decomposition reactions, and in some cases it can not be predicted by Hammett equition. While the TIC of 2E spectra was markedly influenced by the target gas pressure, but the fragmentation pattern of the 2E spectra is independent of it.

酚酞型聚芳醚砜共聚物的合成与表征

研究了酚酞(PP),4,4'-二羟基二苯硫醚(Bis—T),4,4'-二氯二苯砜(DCDPS)三元共聚物(PP/Bis-T)PES的聚合反应过程,热性能及部分力学性能。适宜的聚合温度为185～195℃。(PP/Bis—T)PES属于均相无规共聚物。共聚物具有良好的热稳定性、良好的机械性能。

石墨炉原子吸收光谱法测定磷时基体改进剂的应用研究

本文阐述几种基体改进剂测定磷的效果,发现Pd/Ca混合基体改进剂对测定植物和动物组织中磷最理想,利用氘灯扣背景,其特征量为8.2ng,吸光度线性范围为0～0.220,磷含量为0.144％和1.35％时,相对标准偏差为2％左右,精密度好,抗干扰能力强,测定茶树叶和贻贝中磷比较理想。

稀土与L-苯丙氨酸配合物的pH电位法及量热滴定法研究

本文在25℃和0.15mol·dm~(-3)(NaCl)离子强度下,用pH电位法和量热滴定法测定了十五个稀土元素(Y和除Pm外的镧系元素)与L-苯丙氨酸1∶1配合物的稳定常数及热力学函数。L-苯丙氨酸通过—CO_2~-和—NH_2与稀土离子配位,生成较稳定的1∶1配合物。配合物稳定性呈“四分组效应”。配合物稳定性顺序中Y的位置向轻稀土方向移动。体系的熵变是配位反应驱动力。离子的去水化在配位反应中超重要作用。

联苯取代物的双电荷离子质谱(2E谱)研究

本文研究了联苯取代物双电荷离子2E谱及其取代基效应和靶气压力影响。离子源中产生的双电荷离子的解离反应主要有丢失H原子、C_2H_2、C_2H_4、HR(R为取代基)等反应通道。产物离子中[C_(12)H_8]~(2+)、[C_(12)H_6]~(2+)、[C_(10)H_6]~(2+)等具有相当的稳定性。取代基对不同的反应有不同的影响,主要取决于产物离子的相对稳定性。取代基对分子离子的稳定性的贡献有以下顺序:NH_2>OH>Ph>F>H>Br>NO_2。升高靶气压力,2E谱的总离子流迅速升高,而样品离子流占总离子流的百分数却直线降低。靶气压力影响样品的检测灵敏度,但不影响离子的碎裂途径。

NdCl_3·3P350-AlR_3二元催化体系对双烯烃的定向聚合

由氯化稀土的不同种类磷酸酯配合物与三烷基铝组成的Ziegler-Natta催化剂对双烯烃聚合的研究已有报道,其中聚合活性最高的NdCl_3·3P350—AlR_3二元催化体系对丁二烯溶液聚合及异戊二烯本体聚合的详细研究尚未见报道,本文考察了该体系对双烯烃的定向聚合能力,通过二元体系与相应的催化剂活性体聚合规律的对比,提高对稀土催化聚合反应过程的认识。

立规聚甲基丙烯酸热表征研究

本文对不同立构的聚甲基丙烯酸(PMAA)进行了热表征。实验结果表明,在30℃～200℃内未出现玻璃化转变。间同PMAA分别在-245℃和-280℃发生脱水反应和脱羧,而全同PMAA只在-185℃观察到脱水反应。这种热稳定性的明显差别与不同立构PMAA链上相邻羧酸距离有关。实验数据证实PMAA脱水反应为无规反应,服从一级动力学反应方程。脱水温度和间同立构含量成正比,脱水反应活化能间同PMAA比全同PMAA高～7Kcal/mol。

A clip domain serine protease (cSP) from the Chinese mitten crab Eriocheir sinensis: cDNA characterization and mRNA expression

Clip domain serine protease (cSP), characterized by conserved clip domains, is a new serine protease family identified mainly in arthropod, and plays important roles in development and immunity. In the present study, the full-length cDNA of a cSP (designated EscSP) was cloned from Chinese mitten crab Eriocheir sinensis by expressed sequence tags (ESTs) and PCR techniques. The 1380 bp EscSP cDNA contained a 1152 bp open reading frame (ORF) encoding a putative cSP of 383 amino acids, a 5'-untranslated region (UTR) of 54 bp, and a 3'-UTR of 174 bp. Multiple sequence alignment presented twelve conserved cysteine residues and a canonical catalytic triad (His(185), Asp(235) and Ser(332)) critical for the fundamental structure and function of EscSP. Two types of cSP domains, the clip domain and tryp_spc domain, were identified in the deduced amino acids sequence of EscSP. The conservation characteristics and similarities with previously known cSPs indicated that EscSP was a member of the large cSP family. The mRNA expression of EscSP in different tissues and the temporal expression in haemocytes challenged by Listonella anguillarum were measured by real-time RT-PCR. EscSP mRNA transcripts could be detected in all examined tissues, and were higher expressed in muscle than that in hepatopancreas. gill, gonad, haemocytes and heart. The EscSP mRNA expression in haemocytes was up-regulated after L anguillarum challenge and peaked at 2 h (4.96 fold, P < 0.05) and 12 h (9.90 fold, P < 0.05). Its expression pattern was similar to prophenoloxidase (EsproPO), one of the components of crab proPO system found in our previous report. These results implied that EscSP was involved in the processes of host-pathogen interaction probably as one of the proPO system members. (C) 2009 Elsevier Ltd. All rights reserved.

Early expressed genes showing a dichotomous developing pattern in the lancelet embryo

Lancelets (amphioxus), although showing the most similar anatomical features to vertebrates, never develop a vertebrate-like head but rather several structures specific to this animal. The lancelet anatomical specificity seems to be traceable to early developmental stages, such as the vertebrate dorsal and anterior-posterior determinations. The BMP and Wnt proteins play important roles in establishing the early basis of the dorsal structures and the head in vertebrates. The early behavior of BMP and Wnt may be also related to the specific body structures of lancelets. The expression patterns of a dpp-related gene, Bbbmp2/4, and two wnt-related genes, Bbwnt7 and Bbwnt8, have been studied in comparison with those of brachyury and Hnf-3 beta class genes The temporal expression patterns of these genes are similar to those of vertebrates; Bbbmp2/4 and Bbwnt8 are first expressed in the invaginating primitive gut and the equatorial region. respectively, at the initial gastrula stage. However, spatial expression pattern of Bbbmp2/4 differs significantly from the vertebrate cognates. It is expressed in the mid-dorsal inner layer of gastrulae and widely in the anterior region, in which vertebrates block BMP signaling, The present study suggests that the lancelet embryo may have two distinct developmental domains from the gastrula stage, the domains of which coincide later with the lateral diverticular and the somitocoelomic regions. The embryonic origin of the anterior-specific structures in lancelets corresponds to the anterior domain where Bbbmp2/4 is continuously expressed.

The relation between distribution of zooplankton and salinity in the Changjiang Estuary

Seasonal netzplankton samples from stations in the Changjiang (Yangtze River) Estuary were collected from May, 2004 to February, 2005. The dominant species and their contribution to the total zooplankton abundance were determined. Moreover, the relationship between the salinity and abundance was studied with stepwise linear regression. During the whole year, the salinity was positively correlated with the abundance, while the temperature, negatively. Linear regression analysis showed also a high positive correlation with salinity for total abundance in August and November, while in February and May, no obvious relations were found. The most abundant community was composed of neritic and brackish-water species. The North Passage (NP) (salinity <5) was greatly diluted by freshwater while the North Branch (NB) was brackish water with salinity range of 12-28. Consequently, clear decline in abundance of zooplankton was along the estuarine haloclines from the maximum in the area of high salinity to the minimum in the limnetic zone. Total zooplankton abundance and biomass were lower in NP than the NB in all seasons. In short, the salinity influenced the abundance of each species of zooplankton, and ultimately determined the total abundance of zooplankton. Furthermore, a winter peak in the abundance existed, which might be caused by the flourishing of Sinocalanus sinensis, a widely distributed species in the Changjiang Estuary.

Comparison between compsopogon coeruleus and porphyra yezoensis in their O-2 evolution rates and phycobilisome composition

In order to investigate the possible effects of the ecological environment on photosynthetic activity and the major light harvesting complex, the oxygen evolution rates and composition of phycobilisome from marine red alga Porphyra yezoensis Ueda and freshwater red alga Compsopogon coeruleus (Balbis) Montagne, which could grow and reproduce under salinity up to 35 ppt, were studied. The results showed that the oxygen evolution rate of P. yezoensis in seawater was significantly higher than that of C. coeruleus in freshwater, and P. yezoensis tolerated inorganic ions at a relatively higher concentration than C. coeruleus. Moreover, the phycoerythrin (PE) of P yezoensis was R-phycoerythrin containing alpha, beta, and gamma subunits comprised phycoerythrobilin and phycourobilin. In contrast, the PE from C. coeruleus consisted of alpha, beta, and gamma subunits comprised only phycoerythrobilin but not phycourobilin, suggesting that the PE from C. coeruleus was of a new type.

Comparison of Gene Expression Profiles of Fenneropenaeus chinensis Challenged with WSSV and Vibrio

Microarray technique was used to analyze the gene expression profiles of shrimp when they were challenged by WSSV and heat-inactivated Vibrio anguillarum, respectively. At 6 h post challenge (HPC), a total of 806 clones showed differential expression profile in WSSV-challenged samples, but not in Vibrio-challenged samples. The genes coding energy metabolism enzyme and structure protein were the most downregulated elements in 6 h post WSSV-challenged (HPC-WSSV) tissues. However, a total of 155 clones showed differential expression in the Vibrio-challenged samples, but not in WSSV-challenged samples. Serine-type endopeptidase and lysosome-related genes were the most upregulated elements in tissues 6 h post Vibrio challenge (HPC-Vibrio). Totally, 188 clones showed differential expression in both 6 and 12 HPC-WSSV and HPC-Vibrio samples. Most of the differentially expressed genes (185/188) were downregulated in the samples of 12 HPC-WSSV, whereas upregulated in the samples at 6 and 12 HPC-Vibrio and 6 HPC-WSSV. The expression profiles of three differentially expressed genes identified in microarray hybridization were analyzed in hemocytes, lymphoid organ, and hepatopancreas of shrimp challenged by WSSV or Vibrio through real-time PCR. The results further confirmed the microarray hybridization results. The data will provide great help for us in understanding the immune mechanism of shrimp responding to WSSV or Vibrio.

Warming trend in northern East China Sea in recent four decades

Global warming has become a notable trend especially since an abrupt climate change in 1976. Response of the East China Sea (ECS) to the global warming trend, however, is not well understood because of sparse long-term observation. In this paper, hydrographic observation data of 1957-1996 are collected and reviewed to study climatological variability in northern ECS. Significant warming trends are found in both summer and winter. In summer, the average SST is about 0.46A degrees C higher during the period of 1977-1996 than that of 1957-1976, and the Taiwan Warm Current Water (TWCW) was strengthened. In winter, despite of the cooling effect in the coastal areas adjacent to the Changjiang (Yangtze) River Estuary (CRE), the average SST increase was about 0.53A degrees C during the same period. The causes of this SST warming up in summer are different from in winter. The warming trend and intensification of the TWCW in summer were primarily influenced by the strengthening of the Kuroshio transport, while the warming in winter was mainly induced by the variability of the climate system.

皱纹盘鲍的遗传育种与养殖技术研究

优良的种质是产业发展的重要保证，品种更新和养殖技术的发展已经给世界农业带来了令人瞩目的成就，然而我国水产生物的育种工作刚处于起步阶段，而育种技术的研究则更是滞后。借鉴陆生生物中发展起来的相对成熟的研究方法，可以帮助加快海洋生物遗传育种相关研究的进度。本研究以我国北方海区重要的海洋经济动物－皱纹盘鲍为研究对象，从表型遗传、数量性状遗传等2个方面开展了皱纹盘鲍的遗传育种研究，同时从幼鲍培育密度与分选效应等方面研究了皱纹盘鲍的中间培育技术。 主要结果如下： 1. 皱纹盘鲍的贝壳颜色遗传、食物对贝壳颜色表现型的影响，贝壳颜色与生长速度间的关系 将贝壳颜色为橘红色（O表型）的突变型皱纹盘鲍与贝壳颜色为绿色（G表型）的野生型皱纹盘鲍进行了连续2代的交配实验。结果表明：皱纹盘鲍橘红色的贝壳颜色相对于绿色的贝壳颜色为隐性性状，皱纹盘鲍的贝壳颜色表型受单位点、2个等位基因遗传控制，其中基因型为oo的个体，贝壳颜色的表现型为橘红色（O表型），而基因型为GG或Go的个体，贝壳颜色的表现型为野生型（G表型）。 为探讨食物类型对不同基因型皱纹盘鲍贝壳颜色表现型的影响，对不同贝壳颜色表型的个体投喂不同种类的食物，结果表明，除遗传因素外，皱纹盘鲍的贝壳颜色表现型显著地受食物类型的调控。其中oo基因型的个体，在摄食底栖硅藻（Navicula sp.）和红藻时，贝壳颜色的表型为橘红色；而在摄食褐藻、绿藻和以海带粉为唯一海藻源的人工配合饵料时，贝壳颜色的表型为黄色。GG和Go基因型的个体，在摄食底栖硅藻、红藻时，贝壳颜色的表型为褐红色；在摄食褐藻、绿藻和以海带粉为唯一海藻源的人工配合饵料时，贝壳颜色的表型为绿色。该结果表明，相同基因型的皱纹盘鲍在摄食不同类型的食物时，贝壳表现型不同，即不同类型的食物可以导致2种基因型皱纹盘鲍的贝壳颜色表现型在一定范围内发生转换：oo基因型的个体，贝壳的颜色可以表现为橘红色或者黄色，不会出现野生型皱纹盘鲍的褐红色或绿色；而GG与Go基因型的个体，相应的贝壳颜色表型只能是褐红色或者绿色，不会出现oo基因型可能表现的橘红色或黄色。特定基因型的皱纹盘鲍，在摄食特定类型的食物时贝壳的相应部位可表现出特定的颜色。皱纹盘鲍的这种“食物－贝壳颜色”的相关性可作为一种形态标记，用于标识皱纹盘鲍的个体和群体，该标记技术可用于皱纹盘鲍的养殖技术和遗传学研究。 此外，选用了贝壳颜色遗传学实验中建立的贝壳颜色发生分离的家系为实验材料，以壳长为指标，分析比较了来自相同家系的O表型与G表型个体之间的生长速度。结果表明，在幼鲍发育至412天止的3-5个统计时段内，没有在同一家系来源的2种贝壳颜色表型个体之间检验到生长速度的显著差异。 2. 皱纹盘鲍不同选育群体及杂交群体的贝壳形态参数分析 在皱纹盘鲍的7个群体中（包括已经对生长速度为指标进行了多代人工选育的群体4个、野生群体之间直接杂交繁育的杂交F1群体3个），测量了4-6龄成体样本的壳长（L）、壳宽（W）、壳高（H）和壳重（Sw），并计算了L/（L+W+H）、W/（L+W+H）、H/（L+W+H）和Sw/（L×W×H）等4个壳形态学参数。用方差分析方法（MANOVA、ANOVA）统计并比较了这些壳形态参数在皱纹盘鲍群体间的遗传变异。结果表明，4个壳形态参数在不同群体间变异系数分别为0.34、0.74、2.62和6.54，其中，H/（L+W+H）与Sw/（L×W×H）在各供试群体间均具有较高的多态性且差异达显著水平，表明这2个参数在不同群体间存在较高的遗传变异。由于在活体情况下无法测量壳重（Sw）性状，建议以参数H/（L+W+H）为指标对皱纹盘鲍贝壳形态（如壳型）等进行人工选择。 3. 皱纹盘鲍成体阶段生长性状的遗传参数估计 采用巢式设计，分析了成体阶段不同发育期皱纹盘鲍的壳长与生长速率的遗传力、不同发育期的壳长性状之间的遗传相关、以及不同发育期的生长速率之间的遗传相关，结果表明：（1）壳长遗传力在受精后第70 、130、320、320、380、490与550天的雄性组分估计值分别为0.161 ± 0.075、0.312 ± 0.131、0.326 ± 0.331、0.135 ± 0.228、0.153 ± 0.185和0.180 ± 0.106；雌亲组分估计分别为0.312 ± 0.172、0.699 ± 0.168、0.695 ± 0.168、0.977 ± 0.407、0.427 ± 0.195和0.449 ± 0.027。（2）生长速率遗传力在受精后第320~380天、490 ~ 550天，雄、雌组分估计值分别为0.080 ± 0.120（雄）、 0.210 ± 0.191（雌）以及0.299 ± 0.146（雄）、0.306± 0.148（雌）。雌亲组分的壳长遗传力和生长速率遗传力估计值较大且均达显著水平，表明皱纹盘鲍在成体阶段依然受母性效应的影响。成体阶段生长性状遗传力水平的估计对制定科学的皱纹盘鲍育种方案有指导意义。（3）雄亲组分估计的不同发育期（第390 ~ 550天）壳长间遗传相关为0.597 ~ 1.000，雌亲组分估计为0.589 ~ 1.177。由雄亲、雌亲组分估计，受精后第320~380天与第490 ~ 550天两个发育阶段生长速率间遗传相关均接近于0。雌亲组分估计不同发育期壳长间遗传相关均达显著水平（t0.05, d.f.=13 = 4.33 ~ 11.69，P<0.01），表明壳长性状早期选择有效，即在皱纹盘鲍早期阶段依据壳长性状对个体进行择优或去劣可在后期阶段获得壳长较大的个体。由于使用的雄亲数目少（8个父系半同胞），实验中以雄亲组分估计的遗传参数误差较大。 4. 皱纹盘鲍选育系间的群体杂交 进行了皱纹盘鲍4个人工选育系之间的完全双列杂交实验，以群体交配的方式共建立了16个组合；此外，以大连“98”选群与汕头“S”选群为亲本，以群体交配的方式建立了4个交配组合。对不同方向的杂交组合进行了中亲杂种优势、超亲杂种优势以及配合力等方面的评价。 （1）测量了4个选育群体（R、97、S和J）及其各杂交组合在受精后第9、20和30天时的壳长，统计分析了不同选育系间壳长性状的差异、评价了不同方向杂交组合的中亲与超亲杂种优势、以及配合力。结果如下： 选育系群体内交配繁育的4个组合，在受精后第9、20和30天的壳长均有显著差异，其中，97  97组合在早期发育各阶段均为最小，分别为0.462 ± 0.023mm、0.698 ± 0.057mm和1.476 ± 0.234mm；S  S组合的3次测量值均为最大，分别为0.522 ± 0.023mm、0.824 ± 0.084mm和1.798 ± 0.229mm。 两个方向杂交组合与选育系亲本群体内交配组合的平均值和高亲值比较，得到如下结果：（A）受精后第9天壳长表现正向中亲杂种优势的组合有6个、表现负向中亲杂种优势的组合6个，其中J  97组合的中亲优势率最高，为9.05%；R  S组合最低，为-6.61%。正向高亲杂种优势组合有4个、负向高亲杂种优势组合有8个，其中S  J组合的高亲优势率最高，为5.77%；R  S组合最低，为-7.96%。（B）受精后第20天壳长表现正向中亲杂种优势的组合有7个、表现负向中亲杂种优势的组合5个，其中J  97组合的中亲优势率最高，为12.60%；J  R组合最低，为-8.72%。正向高亲杂种优势组合有3个、负向高亲杂种优势组合有11个，其中J  97组合的高亲优势率最高，为12.20%；J  R组合最低，为-12.67%。（C）受精后第30天壳长表现正向中亲杂种优势的组合有7个、负向中亲杂种优势的组合5个，其中97  S组合的中亲优势率最高，为24.08%；S  97组合最低，为-12.69%。正向高亲杂种优势组合有6个、负向高亲杂种优势组合有6个，其中97  S组合的高亲优势率最高，为15.95%；S  J组合最低，为-19.44%。上述结果表明，皱纹盘鲍不同选育系之间的交配组合，杂种优势率差异很大，因此，通过组配实验，将杂种优势率高的交配组合选择出来应用于生产，可望显著提高目标性状的产量。 对早期发育阶段各生长期壳长性状，亲本一般配合力（GCA）、各杂交组合间特殊配合力（SCA）以及正反交（REC）效应值进行方差分析，结果表明：各亲本GCA差异显著，说明各选育群体存在显著的遗传差异，其中汕头选群“S”在测量的各个生长期均为正值且显著大于其它各亲本；特殊配合力（SCA）以及正反交（REC）效应值较大在各杂交组合间存在显著差异，说明在早期生长发育阶段非加性遗传效应（显性和上位效应）占主导地位。综合各个生长期亲本GCA和杂交组特殊配合力（SCA）以及正反交（REC）效应值，杂交组合97×S在早期生长阶段不仅有较高SCA值而且两个亲本也具有较大的GCA值，表明选育系97和S较适宜作为杂交亲本使用。 （2）大连“98”选群与汕头“S”选群进行2×2因子设计的群体杂交实验，比较了各交配组合早期存活相关性状如受精率、孵化率、变态率以及壳长性状，评价了两个方向杂交组合平均以及不同方向杂交组合的中亲杂种优势率。结果表明早期发育阶段各组合间的受精率无显著差异，而孵化率、变态率等两个杂交方向平均的中亲杂种优势率为5.49%与12.53%，高于壳长性状的优势率（0.936-1.534%）。方差分析结果表明不同方向的杂交组合在早期发育阶段存活相关性状以及壳长性状存在显著差异。孵化率、变态率性状，S×98的中亲杂种优势率分别为13.21%与21.10%，均高于98×S的-3.84%与3.85%；而第10和25d壳长性状，S×98的中亲杂种优势率为1.14%与-2.52%，低于98×S的1.93%与4.41%。 为进一步评价“98”选群与“S”选群不同交配组合在不同温度条件下的生长，进行了基因型与环境的互作研究。从“98”选群与“S”选群的4个交配组合中分别取5月龄幼鲍100头，各组合随机分成3组，每组1个重复，分别于12°C、16°C和 22°C温度条件下进行培育，比较各交配组合基因型与温度对幼鲍生长的影响。不同温度条件下，各组合壳长生长的方差分析结果表明，基因型和温度都能够对幼鲍生长以及最终壳长产生极显著的影响（P < 0. 01），它们的交互作用也达到显著水平（P < 0.05）。杂交子代的幼鲍壳长在12°C、16°C和 22°C温度条件下均表现出杂种优势，双向杂交的中亲杂种优势率分别为5.32%、5.55%和0.03%，表明低温条件（12°C），比高温条件（22°C）下有更强的杂种优势。汕头“S”选群的早期孵化率、变态率、生长性状以及低温条件下幼鲍生长性状的单亲杂种优势率分别为16.64%、42.49%、3.42~5.79%和5.73~9.15%，单亲杂种优势率较大，表明可通过杂交手段，显著地改良汕头“S”选群在早期发育阶段的生长速度、存活率以及幼鲍期的生长性状。本研究的结果支持了Lerner（1954）杂种优势的基因与环境互作学说。 5. 皱纹盘鲍幼鲍的中间培育技术研究 （1）对南方越冬方式的评价 目前，每年的11月前后，将6-7月龄幼鲍运往南方的闽东、闽中、闽南沿海越冬，翌年4月至6月再运回到北方（大连、山东半岛）的养殖模式已经普遍应用于皱纹盘鲍的实际生产，为评价南方越冬的幼鲍培育方式，本研究分别以不同幼鲍材料在闽东三都海湾进行了越冬培育实验。 选择生产上壳长分别为18.37 ± 1.28 mm、15.89 ± 1.10 mm、14.55 ± 1.10 mm与10.59 ± 0.84 mm的幼鲍进行了为期6.5个月的越冬培育，实验结束时，存活率分别为95.56 ± 2.21%、90.55 ± 1.96%、83.97 ± 1.63%与63.30 ± 2.79%。回归分析表明，供试幼鲍在实验起始时的壳长与越冬阶段的存活率成正相关（P = 0.018 < 0.05）。该结果表明，提高幼鲍的规格可显著提高皱纹盘鲍的越冬成活率，因此对于实际生产而言，采取适当措施提高皱纹盘鲍越冬苗种的规格将大幅增加生产的收益，而采用生长速率快的品种、品系或提早采苗均可实现该目标。综合各规格组幼鲍，幼鲍在南方开放性水域进行越冬培育的平均存活率较高，可达到91.38±0.01%，从幼鲍南方越冬的存活曲线可以看出，幼鲍的死亡主要集中在从大连运至福建某地后的15天内，出现死亡高峰的原因可能是由于运输过程的胁迫。此外，2月及4月中下旬水温出现显著降低或回升时也有较明显的死亡出现。该部分结果，对皱纹盘鲍幼鲍的养成管理有指导意义，可以通过合理安排越冬时间、避开死亡的敏感期等措施减少苗种越冬阶段的死亡量。 以中国大连野生群体繁育的子一代为亲本（10♀，10♂），以群体交配的方式繁育F2代个体为实验材料，分别于南方海区以及北方室内升温水方式下进行生长、存活比较，结果表明南方越冬培育方式下，幼鲍壳长的日增长率为81.37-108.89 µm•day-1，与北方室内升温培育条件相比，壳长生长提高了1.08 ~ 1.68倍；而存活率无显著差异。皱纹盘鲍幼鲍南方越冬方式的优势主要体现在鲍鱼幼鲍的生长速度加快，同时节约养殖场的能耗 （2）幼鲍培育过程中的养殖密度与分选效应评价 以3种规格皱纹盘鲍幼鲍为材料比较幼鲍在4个培育密度以及分选或混养条件下壳长的平均日生长及特定生长率。在南方越冬培育方式下实验进行106天，多因素方差分析结果表明实验初始幼鲍的壳长以及培育密度对壳长的生长有显著影响，而且密度效应在不同幼鲍起始规格组中有不同表现；分选没有能够提高不同规格组的生长。本研究的结果对皱纹盘鲍幼鲍的越冬培育有一定的指导作用。

Radioactivity Concentrations in Soils in the Qingdao Area, China

The specific activity concentrations of radionuclides U-238, Th-212, and K-40 of 2300 sampling points in the Qingdao area were measured by an FD-3022 gamma-ray spectrometer. The radioactivity concentrations of U-238, Th-232, and K-40 ranged from 3.3 to 185.3, from 6.9 to 157.2, and from 15.8 to 7834.4 Bq kg(-1), respectively. The air-absorbed dose at I meter above ground, effective annual dose, external hazard index, and radium equivalent activity were also calculated to systematically evaluate the radiological hazards of the natural radioactivity in Qingdao. The air-absorbed dose, effective annual dose, external hazard index, and radium equivalent activity in the study area were 98.6 nGy h(-1), 0.12 mSv, 0.56, 197 Bq kg(-1), respectively. Compared with the worldwide value, the air-absorbed dose is slightly high, but the other factors are all lower than the recommended value. The natural external exposure will not pose significant radiological threat to the population. In conclusion, the Qingdao area is safe with regard to the radiological level and suitable for living.