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1.
贵州珊瑚是一种个体大,隔壁多而长,鳞板带宽,构造较特征的双带型珊瑚。俞建章(1931)创立该属时仅描述了Kueichouphyllum sinense Y(?)一种,产于下石炭统大塘阶上司组,视为Yuanophyllum带下亚带的带化石。俞建章(1933)研究我国南方下石炭统珊瑚化石,又描述了该属另一新种和一新亚种Kueichouphyllum heishihkuanense Y(?), K.sinense gracile Y(?),其层位仍为大塘阶上司组。杨敬之、盛金章、吴望始等(1962)总结中国的石炭系时指出,我国南方地区大塘早期地层里产有许多Kueichouphyllum sinense Y(?),与Thysanophyllum共生,主张以Thysanophyllum-Kueichouphyllum sinense共同作  相似文献   

2.
出露于新疆南天山东部的阿尔皮什麦布拉克组属于近岸、富氧、温暖的浅海沉积。该组自上一个世纪三十年代创建以来,有关它的地质时代归属一直存在着争论,作者根据珊瑚(包括四射珊瑚、床板珊瑚和日射珊瑚)、介形类和牙形类等门类化石的综合研究,主张将阿尔皮什麦布拉克组置于下泥盆统下部的洛赫柯夫阶。  相似文献   

3.
中泥盆世吉维特晚期(更精确的说是在中吉维特期末)发生的生物更替事件使大量的头贝、全部的泡沫珊瑚亚目以及大多数的绳珊瑚科和内板珊瑚科惨遭灭绝。晚泥盆世弗拉期出现了许多新生分子,诸如Micto-phyllum,Wapitiphyllum,Pseudozaphrentis,Peneckiella等。根据珊瑚的不同组合特征可以鉴别出它们的地质时代。华南自上而下可划分出4个四射珊瑚组合,分别为上泥盆统弗拉阶(Frasnian):4)Disphyllum-Wapitiphyl-lum组合(牙形类gigas或rhenana带和hassi-jamieae带),3)Mictophyllum-Pseudozaphrentis组合(牙形类asymmetricus带);中泥盆统吉维特阶(Givetian):2)Endophyllum-Sunophyllum组合(牙形类varcus带的中部和下部之上段),1)Stringophyllum-Paramixogonaria组合(牙形类hemiansatus带-varcus带最下部)。  相似文献   

4.
廖卫华  梁昆 《古生物学报》2020,59(2):179-191
贵州省惠水县王佑镇至翁赖村一带出露中泥盆统上部浅海底栖相翁赖组(新名),该组以陆源碎屑沉积居多、沉积厚度较大、群体珊瑚很少而单体珊瑚却比较发育为主要特征。其中,翁赖组上部层位与贵州独山剖面独山组鸡窝寨段相当,时代为中泥盆世吉维特期的晚期(late Givetian)。翁赖组上部之底非常特征的中华海绵珊瑚化石(Sinospongophyllum)与中泥盆统上部吉维特阶标准的腕足类化石鸮头贝(Stringocephalus)共栖。该属与华南地区中泥盆世晚期标准的内板珊瑚(Endophyllum)的内部骨骼构造非常相似,仅外部形态不同。在华南地区,内板珊瑚和中华海绵珊瑚的层位非常稳定,大致相当于吉维特阶的下varcus带。文中描述翁赖组上部四射珊瑚8属13种,包括Calceola intermediata inflata Yoh,,Cystiphylloides kwangsiense Yoh,C.secundus (Goldfuss),C.sp.,Paramixogonaria wangyouensis sp.nov.,Grypophyllum? sp.,Mictophyllum shaw...  相似文献   

5.
ShensiphyllumGeetYü,1974为丛状复体珊瑚,以发育一列马蹄型鳞板,羽榍扇形排列为主要特征,是志留纪四射珊瑚已知唯一发育马蹄型鳞板的属。该属在我国上扬子区广泛分布于上兰多维列统(Llandovery)特列奇阶(Telychian)中,主要产自川北、陕南的宁强组、云南大关的大路寨组(中、上Telychian阶))、湖北长阳的纱帽组及四川朝天的王家湾组(下特列奇阶)。文中报道和描述川北朝天王家湾组中发现的3个新种Shensiphyllumsimplexsp.nov.,S.proliferumsp.nov.,S.intermediumsp.nov.。王家湾组是已知ShensiphyllumGeetY櫣产出的最低层位。详细讨论该属的骨骼构造特征、生长繁殖方式,探讨该属起源及其演化,根据新资料修订该属的属征,赞同将该属置PhacellophyllidaeWedekind科。  相似文献   

6.
唐兰 《古生物学报》2006,45(3):374-383
Shensiphyllum Ge et Yǖ,1974为丛状复体珊瑚,以发育一列马蹄型鳞板,羽榍扇形排列为主要特征,是志留纪四射珊瑚已知唯一发育马蹄型鳞板的属。该属在我国上扬子区广泛分布于上兰多维列统(Llandovery)特列奇阶(Telychian)中,主要产自川北、陕南的宁强组、云南大关的大路寨组(中、上Telychian阶))、湖北长阳的纱帽组及四川朝天的王家湾组(下特列奇阶)。文中报道和描述川北朝天王家湾组中发现的3个新种Shensiphyllum simplex sp.nov.,S.proliferum sp.nov.,S.intermedium sp.nov.。王家湾组是已知Shensiphyllum Ge et Yǖ产出的最低层位。详细讨论该属的骨骼构造特征、生长繁殖方式,探讨该属起源及其演化,根据新资料修订该属的属征,赞同将该属置Phacellophyllidae Wedekind科。  相似文献   

7.
虽然在华南中泥盆世艾菲尔期(Eifelian)较深水或斜坡相地层中产有许多国际标准的牙形类带化石,但在广阔的浅海相地层中却很难寻觅到其踪影。华南浅海相沉积地区是否缺失艾菲尔阶?在野外众多剖面的实地考察中表明,从下泥盆统埃姆斯阶到中泥盆统吉维特阶都是连续沉积,中间并没有发现地层的缺失或间断现象。浅海相的艾菲尔阶与其上覆的吉维特阶和下伏的埃姆斯阶都是连续沉积,说明可能是由于海水太浅,不太适合那些国际标准分子的生存而已。艾菲尔期中期末发生一次生物灭绝事件(Mid-Eifelian event),favositids,heliolitids和许多古老类型的珊瑚在地球上灭绝。华南艾菲尔期四射珊瑚可以划分成下、上两个完全不同的组合:1)Utara-tuiasinen sis-Sociop hyllum minor组合(牙形类partitus带—costatus带);2)Columnaria spinosa-Dendrostella praerhenana组合(牙形类australis带—kocklianus带)。  相似文献   

8.
江西晚石炭世晚期及早二叠世早期的四射珊瑚   总被引:2,自引:2,他引:0  
记述江西彭泽、于都、乐平、玉山、崇义及上高等地上石炭统船山组和下二叠统栖霞组的四射珊瑚16种,其中船山组有11属12种(包括8新种、1未定种),栖霞组有3属4种(包括3新种、1未定种).根据珊瑚化石的分布规律,将船山组的珊瑚建立2个组合,并与有关地区的珊瑚组合进行了对比.通过对这些珊瑚形态构造特征的剖析,文章还探讨了晚石炭世晚期及早二叠世早期本区珊瑚的生态特征.  相似文献   

9.
本文描述了产自北秦岭中泥盆统西汉水群上部的10属12种四射珊瑚化石,包括3新种。由于其中出现了Temnophyllum waltheri, Grypophyllum tenue, Tabulophyllum annulatum和Disphyllum hsianghsienense等德国、苏联和我国南方Givetian阶的常见分子,因此,甘肃宕昌产上述珊瑚化石的地层时代应属于中泥盆世晚期。本文还根据笔者对保存在加拿大和德国等地自然博物馆中某些珊瑚属模式标本的观察和重新研究,讨论了一些珊瑚属种之间的亲缘关系并厘订了某些属征。  相似文献   

10.
一、前言 1977年,云南会泽县铅锌矿勘探队在云南会泽县铅锌矿区的石炭纪地层剖面(A—A′和B—B′)采得一批珊瑚化石标本,有四射珊瑚和床板珊瑚共9属12种和1未定种,包括1新属和9新种,产化石层位为下石炭统上司段、上石炭统威宁组上部和马平组底部,珊瑚化石较为丰富的是在上司段。下石炭统在结山组和上石炭统威宁组中、下部是含铅锌矿的层位。据有关资料证实,铅锌矿的成因与一定的古地理条  相似文献   

11.
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   

12.
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   

13.
This report attempts to formulate reference ranges of elemental concentrations for 15 trace elements in selected human tissues and body fluids. A set of samples consisting of whole blood, blood serum, urine, milk, liver, and hair were chosen and considered for 15 elements of biological significance: As, Cd, Co, Cr, Cu, F, Fe, I, Hg, Mn, Mo, Ni, Pb, Se, and Zn. The results represent wholly or partially data received from 40 countries of the global regions of Africa, Asia, Europe, North, South, and Central America, Australia, and New Zealand. This survey, even if qualitative, has been useful in demonstrating certain trends of trace-element scenarios around the world. It is of course recognized that both diet and environment exert a strong influence on the distribution pattern of several elements, such as As, Cd, Mn, Pb, Se, and Zn. A limited comparison of the available information on soil status of different countries reflected some interesting associations for elements, such as Mn and Zn. Importantly, this study revealed that only a few countries were in a position to identify a reasonable amount of data on samples requested for this project. Regretably, for a number of countries, any dependable data for even such essential elements as Cu, Fe, and Zn were not available. In view of the nutritional importance of many elements, the time is ripe for concerted efforts by intergovernmental agencies to initiate investigations or commission task forces/projects to generate reliable reference data for selected global regions, which sadly lack data of any kind at present.  相似文献   

14.
The unitary conductances and permeability sequences of the rat connexin40 (rCx40) gap junction channels to seven monovalent cations and anions were studied in rCx40-transfected neuroblastoma 2A (N2A) cell pairs using the dual whole cell recording technique. Chloride salt cation substitutions (115 mM principal salt) resulted in the following junctional maximal single channel current-voltage relationship slope conductances (γj in pS): CsCl (153), RbCl (148), KCl (142), NaCl (115), LiCl (86), TMACl (71), TEACl (63). Reversible block of the rCx40 channel was observed with TBA. Potassium anion salt γj are: Kglutamate (160), Kacetate (160), Kaspartate (158), KNO3 (157), KF (148), KCl (142), and KBr (132). Ion selectivity was verified by measuring reversal potentials for current in rCx40 gap junction channels with asymmetric salt solutions in the two electrodes and using the Goldman-Hodgkin-Katz equation to calculate relative permeabilities. The permeabilities relative to Li+ are: Cs+ (1.38), Rb+ (1.32), K+ (1.31), Na+ (1.16), TMA+ (0.53), TEA+ (0.45), TBA+ (0.03), Cl (0.19), glutamate (0.04), and NO3− (0.14), assuming that the monovalent anions permeate the channel by forming ion pairs with permeant monovalent cations within the pore thereby causing proportionate decreases in the channel conductance. This hypothesis can account for why the predicted increasing conductances with increasing ion mobilities in an essentially aqueous channel were not observed for anions in the rCx40 channel. The rCx40 effective channel radius is estimated to be 6.6 Å from a theoretical fit of the relationship of relative permeability and cation radius.  相似文献   

15.
A new polynitro cage compound 2, 4, 6, 8, 10, 12, 13, 14, 15-nonanitro-2, 4, 6, 8, 10, 12, 13, 14, 15-nonaazaheptcyclo [5.5.1.1(3,11).1(5,9)] pentadecane (NNNAHP) was designed in the present work. Its molecular structure was optimized at the B3LYP/6-31 G(d,p) level of density functional theory (DFT) and crystal structure was predicted using the Compass and Dreiding force fields and refined by DFT GGA-RPBE method. The obtained crystal structure of NNNAHP belongs to the P-1 space group and the lattice parameters are a = 9.99 ?, b = 10.78 ?, c = 9.99 ?, α = 90.01°, β = 120.01°, γ = 90.00°, and Z = 2, respectively. Based on the optimized crystal structure, the band gap, density of state, thermodynamic properties, infrared spectrum, strain energy, detonation characteristics, and thermal stability were predicted. Calculation results show that NNNAHP has detonation properties close to those of CL-20 and is a high energy density compound with moderate stability.  相似文献   

16.
17.
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   

18.
We investigated the uptake of inorganic elements (Be, Na, Mg, K, Ca, Sc, Mn, Co, Zn, Se, Rb, Sr, Y, Zr, Ce, Pm, Gd, and Hf) and the effect of Ca on their uptake in carrots (Daucus carota cv. U.S. harumakigosun) by the radioactive multitracer technique. The experimental results suggested that Na, Mg, K, and Rb competed for the functional groups outside the cells in roots with Ca but not for the transporter-binding sites on the plasma membrrane of the root cortex cells. In contrast, Y, Ce, Pm, and Gd competed with Ca for the transporters on the plasma membrane. The selectivity, which was defined as the value obtained by dividing the concentration ratio of an elemental pair, K/Na, Rb/Na, Be/Sr, and Mg/Sr, in the presence of 0.2 and 2 ppm Ca by that of the corresponding elemental pair in the absence of Ca in the solution was estimated. The selectivity of K and Rb in roots was increased in the presence of Ca. The selectivity of Be in roots was not affected, whereas the selectivity of Mg was increased by Ca. These observations suggest that the presence of Ca in the uptake solution enhances the selectivity in the uptake of metabolically important elements against unwanted elements.  相似文献   

19.
The variation with age of the 18 trace element mass fractions and some histological characteristics of intact prostate glands of 50 subjects aged 0–30 years was investigated by instrumental neutron activation analysis, inductively coupled plasma atomic emission spectrometry, and a quantitative morphometric analysis. Mean values ± standard error of the mean (M ± SΕΜ) for the mass fractions (in milligrams per kilogram wet tissue) of these trace elements in pre-puberty were: Al 28.5 ± 9.0, B 0.40 ± 0.11, Ba 1.48 ± 0.44, Br 10.5 ± 1.5, Ca 241 ± 30, Cl 3,203 ± 278, Cu 3.51 ± 0.89, Fe 33.7 ± 4.1, K 2,364 ± 145, Li 0.020 ± 0.004, Mg 153 ± 23, Mn 0.46 ± 0.06, Na 2,286 ± 130, P 1,391 ± 100, S 1,698 ± 132, Si 62 ± 11, Sr 0.38 ± 0.08, and Zn 27.6 ± 2.3. During puberty and postpuberty, when there is a significant increase in circulating androgens, the mean values were: Al 7.2 ± 1.4, B 0.21 ± 0.05, Ba 0.25 ± 0.06, Br 5.8 ± 1.0, Ca 433 ± 81, Cl 2,314 ± 201, Cu 1.77 ± 0.13, Fe 20.9 ± 1.6, K 2,585 ± 118, Li 0.0088 ± 0.0014, Mg 232 ± 27, Mn 0.34 ± 0.04, Na 1,875 ± 107, P 1,403 ± 98, S 1,673 ± 73, Si 22.2 ± 3.1, Sr 0.22 ± 0.03, and Zn 93.3 ± 8.9. Mean values (M ± SΕΜ) of percent volumes (%) of the stroma, epithelium and lumen in the prostate before puberty were 73.4 ± 2.6, 20.4 ± 1.7, and 4.45 ± 0.94, respectively, versus 46.5 ± 2.5, 38.5 ± 1.9, and 14.9 ± 1.2 during puberty and postpuberty. This work’s results confirm that the Zn mass fraction in prostate tissue is an androgen-dependent parameter. For the first time it has been demonstrated that the glandular lumen is a main pool of Ca, Mg, and Zn accumulation and that the stroma is a main pool of Al, B, Ba, Br, Cl, Cu, Fe, Mn, Na, and Si accumulation in the normal human prostate, for the age range 0–30 years. It was concluded that the Ca, Mg, and Zn binds tightly within the prostatic fluid, because the volume of glandular lumen reflects the volume of prostatic fluid.  相似文献   

20.
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   

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