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1.
记述了发现于莱阳上白垩统将军顶的半枚蛋化石,据其保存较尖的一端,蛋壳外表面光滑无纹饰,蛋壳较薄,紧密排列的棱柱状壳单元,壳单元边缘由致密的方解石组成,以及气孔较少,气孔呈圆形或椭圆形等特征,将其归入棱柱形蛋科,建立新蛋属新蛋种:梨乡莱阳蛋(Laiyangoolithus lixiangensis oogen.et oosp.nov.)。梨乡莱阳蛋的发现不仅丰富了莱阳恐龙蛋化石群组成,同时也增加了棱柱形蛋类的古地理分布,并为研究伤齿龙类的多样性和古地理分布提供了新的证据。  相似文献   

2.
浙江省义乌市发现了一种新类型的恐龙蛋化石,外表面上具有大致相互平行的波状分枝裂隙。这种奇特的纹饰表明这种蛋不属于已知的任何蛋科。有趣的是,它们与曾经被归于树枝蛋科的南马东阳蛋(Dongyangoolithus nanmaensis)有一些相同的蛋壳显微特征:外表面的分枝裂隙和被巨大空腔分隔的壳单元集合体。考虑到地点和层位都很接近,这一新类型的恐龙蛋和南马东阳蛋应被归于一新蛋科。由于这种新类型恐龙蛋的壳单元集合体及裂隙的形态不同于南马东阳蛋,因此又建立了一个新的蛋属、蛋种——赤岸多裂隙蛋(Multifissoolithus chianensis)。新蛋科与圆形蛋科的圆形蛋属(Spheroolithus)有较近的亲缘关系,还具有一种过渡型的气体交换系统。  相似文献   

3.
甘肃省早白垩世地层中,出土了大量恐龙骨骼以及恐龙足迹化石,但是至今未有蛋化石的报道。根据发现于兰州-民和盆地下白垩统河口组的蛋壳化石,建立一恐龙蛋新蛋属、蛋种,并将其归于一新蛋科:Polyclonoolithidae(多小枝蛋科)。新发现的蛋化石标本不同于所有已知的恐龙蛋类型,具有独特的显微特征组合:分叉的蛋壳单元向外延伸至蛋壳外表面,并未在靠近蛋壳外表面处融合成层;弦切面上具相互链接或独立的多角形的蛋壳单元;以及不规则的气孔道。中国的恐龙蛋化石大多出自晚白垩世地层,仅在辽宁有早白垩世恐龙蛋的报道。新发现扩展了中国恐龙蛋化石的地质和地理分布,也有可能为圆形蛋科蛋壳结构的起源提供新的认识。  相似文献   

4.
山东莱阳晚白垩世恐龙蛋化石一新类型   总被引:4,自引:0,他引:4  
山东莱阳是中国最早发现的含有丰富的晚白垩世恐龙及恐龙蛋化石产地。上个世纪50~60年代,周明镇(1951,1954)及杨钟健(1954,1959,1965)对莱阳首次发现的恐龙蛋化石进行了研究。1974年,赵资奎、蒋元凯在前人工作基础上,采用显微镜技术方法重新研究了莱阳恐龙蛋壳的显微结构,结果发现它们的显微结构有很大差异。根据赵资奎(1975)提出的恐龙蛋分类方法(Parataxonomy),将莱阳地区已发现的恐龙蛋分别归入圆形蛋科(spheroolithidae)、椭圆形蛋科(Ovaloolithidae)和长形蛋科(Elongatoolithidae)等3个科,共5个属12个种(赵资奎,1979,1993)。最近,大连自然博物馆在整理馆存的化石标本时,发现有4枚形状为扁圆形的恐龙蛋化石是1973年10月从山东莱阳将军顶采集到的。根据目前有关莱阳地区晚中生代地层划分修订的标准(胡承志等,2001),这些标本的出土层位应为上白垩统王氏群将军顶组。我们的初步观察表明,蛋化石的形状、大小及其蛋壳显微结构特征与上述已报道的莱阳恐龙蛋3个类群的明显不同,在此简单记述,以期对莱阳地区晚白垩世恐龙蛋群的综合研究提供些许资料。  相似文献   

5.
辽宁昌图上白垩统泉头组恐龙蛋化石的分类订正   总被引:1,自引:0,他引:1  
重新描述了20世纪20年代发现于辽宁省昌图地区的恐龙蛋化石。通过对这些标本的宏观和微观形态特征的观察与测量数据分析,将其归入圆形圆形蛋(Spheroolithus spheroides)和厚皮圆形蛋(Spheroolithus megadermus),这是目前这两个蛋种的第二次化石记录。这两个蛋种首次发现于山东莱阳上白垩统将军顶组,根据昌图及其邻近地区恐龙蛋化石与山东莱阳恐龙蛋化石群的对比,结合松辽盆地近年来泉头组的研究成果,认为泉头组的地质时代为晚白垩世早、中期。  相似文献   

6.
浙江天台盆地上白垩统赤城山组发现的巨型长形蛋类可鉴定为西峡巨型长形蛋(Macroelongatoolithusxi xiaensis)和一新蛋属、新蛋种——桥下巨型纺锤蛋(Megafusoolithus qiaoxiaensis oogen.etoosp.nov.)。西峡巨型长形蛋此前仅发现于河南西峡盆地,其特征为个体巨大(35cm),蛋壳外表面具瘤点状纹饰,蛋壳锥体层与柱状层界线明显,呈波浪形,锥体层与柱状层厚度之比为1:5—1:2。已记述的产自天台的张氏巨型长形蛋(M.zhangi)和产自河南西峡盆地的西峡长圆柱蛋(Longiteresoolithus xixiaensis)均为西峡巨型长形蛋的同物异名。桥下巨型纺锤蛋的特征包括蛋壳中部外表面具有棱脊状纹饰,蛋壳锥体层与柱状层界线不明显,二者厚度之比近1:3,这些特征区别于巨型长形蛋属。目前已知巨型长形蛋科仅包含巨型长形蛋属和巨型纺锤蛋属,订正的科征为:蛋化石巨大,长径大于35cm;蛋长形,两端大致对称,长宽之比约为3:1;蛋化石在蛋窝中一般两枚为一组,呈单层圆环状排列,蛋窝直径近3m;蛋壳外表面具瘤点状或棱脊状纹饰,蛋壳由锥体层与柱状层组成。这些特征明显区别于其他类型的蛋化石,因此它们代表了一个独立的蛋科:巨型长形蛋科(Macroelongatoolithidae)。  相似文献   

7.
浙江天台盆地上白垩统赤城山组长形蛋科一新蛋属   总被引:2,自引:0,他引:2  
浙江天台盆地上白垩统赤城山组发现一新的恐龙蛋类型。依据蛋化石形态、大小和蛋壳柱状层生长纹呈波浪形等特征,将其归入长形蛋科(Elongatoolithidae)。这枚恐龙蛋的蛋壳外表面具网状纹饰,蛋壳锥体层与柱状层界线明显,二者厚度之比近1:2,气孔道细而直,这些特征区别于其他长形蛋科的成员,因此,建立一新的蛋属、蛋种:网纹副长形蛋(Paraelonga-toolithus reticulatus oogen.et oosp.nov.),代表晚白垩世早期长形蛋科的新成员。  相似文献   

8.
记述了产自浙江省天台盆地的网形蛋类新材料,建立一新蛋属——拟网形蛋属(Paradictyoo lithusoogen.nov.),两个新蛋种:庒前拟网形蛋(Paradictyoolithus zhuangqianensis oogen.etoosp.nov.)和下西山拟网形蛋(P.xiaxishanensis oogen.et oosp.nov.)。在此基础上,重新系统描述其他已知4种网形蛋属成员的结构特征,并对网形蛋类的分类进行了订正:网形蛋属(Dictyoolithus)仅保留红坡网形蛋(D.hongpoensis Zhao,1994)一个蛋种;建立一新蛋属:原网形蛋属(Protodictyoolithus oogen.nov.),将发现于河南西峡盆地的内乡网形蛋(D.neixiangensis Zhao,1994)和发现于山东莱阳盆地的蒋氏网形蛋(D.jiangi Liu&Zhao,2004)分别修订为:内乡原网形蛋(修订种)(Protodictyoolithus neixiangensis(Zhao,1994)comb.nov.)和蒋氏原网形蛋(修订种)(P.jiangi(Liu&Zhao,2004)comb.nov.);此外,发现于吉林公主岭早白垩世的公主岭网形蛋(D.gongzhulingensis Wang et al.,2006)并不属于网形蛋类,而应归入似蜂窝蛋类(Similifaveoolithus),将其修订为公主岭似蜂窝蛋(修订种)(Similifaveoolithus gongzhulingensis(Wangetal.2006)comb.nov.)。  相似文献   

9.
记述了江西省上高县发现的一窝不完整蛋窝的恐龙蛋。根据恐龙蛋宏观形态和蛋壳显微结构特征将其归入石嘴湾珊瑚蛋(Coralloidoolithus shizuiwanensis)。该窝恐龙蛋为近圆形球体,平均长径11.8 cm,平均赤道直径9.8 cm,蛋壳厚度可达2.5 mm;蛋壳由锥体层与柱状层组成,锥体层较薄,柱状层可分为内层、中间层和外层,内层发育致密的水平生长纹,中间层结构松散,含有大量暗色物质,中间层和外层发育次生壳单元。依据新标本的观察,明确珊瑚蛋属在石笋蛋科中以柱状层中间层结构松散为主要分类特征。上高新标本的发现,丰富了石嘴湾珊瑚蛋的古地理分布,同时也为上高地区晚白垩世含恐龙蛋红层的对比提供了新的证据。  相似文献   

10.
依据采自江西省萍乡地区上白垩统周田组的恐龙蛋化石,记述了蜂窝蛋科(Faveoloolithidae)副蜂窝蛋属(Parafaveoloolithus)一新蛋种。材料包括一枚较完整的蛋和若干破碎蛋壳。根据蛋壳弦切面呈蜂窝状结构,径切面蛋壳中、上部蛋壳局部呈现由6~10个以上壳单元成群聚集一起等特征,将其订为一新蛋种——萍乡副蜂窝蛋(Parafaveoloolithus pingxiangensis oosp.nov.)。  相似文献   

11.
The aim of this report has been to present results concerning analytical quality controls of Hg analysis of fish and sediment, analyses of Fe, Ca, total-P, K, pH, alkalinity, conductivity, colour and hardness (Ca + Mg) of lake water samples. Despite the fact that these are standard parameters in many regular water control programs, there are major differences in the reliability with which these parameters can be determined. The focus here is on an overall inter-laboratory comparison between the parameters. Six laboratories have been involved in the analysis. Selected results: pH gives the lowest (average) relative standard deviation (error), about 2 %; conductivity gives an error of about 5–7 %; alkalinity yields an average error of as much as 13–25 %, which is the largest among the parameters studied here; colour also gives a high error, 9–15 %; hardness gives a relative standard deviation of about 6–7 %. Of the other parameters (i. e., Hg, Fe, Ca and P), Hg gives the best reliability and Fe and P the lowest. To have knowledge of the reliability of the analytical data is of paramount importance in most control programs and research projects.  相似文献   

12.
Summary Concentration of N, P, K, Ca, Mg and S in summer groundnut crop was higher than in kharif while Zn, Fe, Mn and Cu contents were higher in summer crop. Kernel's N, P and Zn; Leaflet's Ca and Mn; Stem's K and Fe; Root's S and Cu and Petiole's Mg contents were highest. Shell's N, P, K, Mg, S, Zn and Cu; Kernel's Ca, Fe and Mn contents were the least. N, P, K, S, Zn and Cu concentrations decreased linearly as the crop grew. Ca, Mg, Fe and Mn concentrations did not display any distinct pattern. Ca concentration was positively correlated with pod yield in both the seasons.  相似文献   

13.
The cell has been represented as a charged liquid drop. Contrary to the DLVO-theory, the effect of the surface potential upon the value of the interfacial tension of the cell membrane has also been taken into consideration. The cell membrane has visco-elastic properties and its constituents may move against each other. Cell movement is caused by the appearance of a small number of the electrically charged constituents of the cell membrane on the leading edge of the cell. This produces a local decrease in the surface tension and the cell membrane expansion. At the moment of contact between two cells proton transfers occur between the strongly negatively charged microvilli of one cell and the body of the other, analogous to a condenser breakdown. This, through the effect on the surface tension, causes contact inhibition of movement. The distribution of the proton dissociable groups modifies the interaction between the cells (differentiation) and between the cell and the substratum (adhesion). Adsorption of the charged compounds at the surface of the cell membrane, decreasing the surface potential and increasing the surface tension, causes the phenomena of chemotaxis, phagocytosis and pinocytosis. Cell division, considered in the terms of the surface energy, requires an adequate supply of considerable quantities of energy inversely proportional to the surface potential value. In case of a reduction of the distance between the cells, their surface potential and the energetic barrier of the cell division processes increases, and causes contact inhibition of cell division. Due to their high charge, division of neoplastic cells is inhibited much later than division of normal cells, or is completely ininhibited due to geometric conditions. Fusion of the cell membrane in the intra-cellular and intercellular processes is a reverse process in relation to the cell division.  相似文献   

14.
15.
Acute and chronic toxicity tests for malathion, diazinon, copper (Cu), mercury (Hg), lead (Pb), zinc (Zn), nickel (Ni), and iron (Fe) were conducted. Mortalities ofBarilius vagra andCyprinus carpio (common carp) were variable but LC50-96 hr were similar for pesticides. AdultB. vagra seem to be more sensitive to malathion than juvenile carp. Both juvenile carp and adultB. vagra were extremely sensitive to diazinon. Long-term exposure to pesticides modified morphology and behavior. The LC50-96 values for Cu, Hg, and Pb were 0.3, 0.16, and 0.44, respectively, for smaller fish and 1.0, 0.77, and 1.33, respectively, for larger fish. Replicate LC50 values for Zn, Ni, and Fe were somewhat variable, and for these metals, the size of the fish seemed to affect response because LC50 values increased as fish size increased. Cooper, Pb, Zn, and Fe residues following exposure to sublethal concentrations of these metals for 15 d were significantly greater in whole juvenile common carp than in controls.  相似文献   

16.
The effect of age and gender on major, minor, and trace element contents in the intact rib bone of 80 relatively healthy 15–55-year-old women and men was investigated. Contents or upper limit of contents of 16 chemical elements in the rib bone were determined by inductively coupled plasma atomic emission spectrometry (ICP-AES). Mean values (M?±?SΕΜ) for the mass fraction of Ba, Ca, Cu, Fe, K, Li, Mg, Na, P, S, Sr, and Zn (milligram per kilogram of dry bone) were as follows: 2.54?±?0.16, 171,400?±?4,050, 1.35?±?0.22, 140?±?11, 1,874?±?71, 0.049?±?0.011, 2,139?±?38, 5,378?±?88, 75,140?±?1,660, 1,881?±?51, 291?±?20, and 92.8?±?1.5, respectively. The upper limits of contents of Al, B, Mn, and V were <7.20, <0.65, <0.36, and <0.03, respectively. Statistically significant tendency for the Ca, Mg, and P content to decrease with age was found in the human rib bone, regardless of gender. The mass fraction of Fe in the male rib bone increases with age. It was shown that higher Ca, Mg, Na, P, and Sr mass fractions as well as lower Fe content were typical of female ribs as compared to those in male ribs.  相似文献   

17.
18.
The sieve-element plastids of 69 species of theCaryophyllales were investigated by transmission electron microscopy. All contained the specific subtype-P3 plastids characterized by a peripheral ring of protein filaments. The presence or absence of an additional central protein crystal and their shape being either polygonal or globular as well as the average sizes of the sieve-element plastids are useful features in the characterization of some families.—Barbeuia contains sieve-element plastids that confirm its placement within thePhytolaccaceae. Lyallia differs fromHectorella by including small starch grains in their sieve-element plastids, which otherwise by their globular crystals negate a closer connection to theCaryophyllaceae. The lack of a central protein crystal in its form-P3fs plastids placesMicrotea best within theChenopodiaceae. Sarcobatus, a so far uncontested member of theChenopodiaceae, contains form-P3cf plastids, i.e., including a central crystal not found elsewhere in this family.Telephium andCorrigiola, shifted back and forth betweenMolluginaceae andCaryophyllaceae, have form-P3cf(s) plastids with a polygonal crystal which favor their placement within theCaryophyllaceae.  相似文献   

19.
A review is presented of issues relevant to the definition, measurement, and classification of stimuli, situations, and environments. Problems such as the lack of adequate definitions of concepts, error and bias in measurement procedures, confusion between measurement of a concept and measurement of its behavioral effects, and the lack of agreement among alternative measures are emphasized. It is suggested that concepts be defined in terms of objective characteristics while allowing for the study of the transactional relationship between organism and environment. The work of the ethologists in defining stimuli while studying their relationship to different organismic states and situational contexts is emphasized in this regard. Following Brunswik, it is also suggested that wherever possible there be a representative sampling of variables in natural settings. Note from the editors: From time to time, Human Ecology will publish a review article. Our first in this series is a review by a psychologist of basic definitional and conceptual problems in environmental studies.This paper was prepared while the author was a Visiting Research Fellow at the Educational Testing Service. The support of ETS and my colleagues in the Division of Psychological Studies is gratefully acknowledged. The review was also supported in part by a grant from the Rutgers University Research Council.  相似文献   

20.
The goal of this article was to establish reference ranges of the concentration of trace elements in human serum and to compare these results with those reported by other authors. We describe the sample preparation and measurement conditions that allow the rapid, precise, and accurate determination of Al, As, B, Be, Cd, Co, Cu, Fe, Li, Mn, Mo, Ni, Rb, Se, Sr, and Zn in human serum samples (n=110) by inductively coupled plasma-mass spectrometry (ICP-MS). Accuracy and precision were determined by analyzing three reconstituted reference serum samples by comparison with other methods and by the standard addition procedure. The advantages of the ICP-MS method include short time of analysis of the elements mentioned, low detection limit, high precision, and high accuracy. Disadventages include a high risk of contamination due to the presence of some of the elements of interest in the environment, the relatively delicate sample handling, and the high cost of the equipment.  相似文献   

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