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1.
从有孔虫动物群论华南泥盆-石炭系之分界   总被引:13,自引:1,他引:12  
本文研究了华南地区法门阶至杜内阶有孔虫动物群,并由下而上建立了五个有孔虫化石组合带(Ⅰ—Ⅴ),它们分布在黔南尧梭组上部(Ⅰ),者王组(Ⅱ),革老河组(Ⅲ),汤耙沟组下部(Ⅳ)和汤耙沟组中部(Ⅴ);在湘中则见于邵东组(Ⅱ),孟公坳组(Ⅲ),刘家塘组下部(Ⅳ)和刘家塘组中部(Ⅴ)。根据有孔虫动物群的分析,以及与西欧狄南盆地和苏联一些地区相当层位中有孔虫组合的对比,笔者认为以组合带Ⅲ之顶界作为泥盆-石炭系的分界。在黔南泥盆-石炭系的界线置于革老河组之顶;在湘中则位于孟公坳组之顶。因此,革老河组或孟公坳组属法门阶上部,改变了我国华南地区将这一界线置于邵东组之底或革老河组(包括者王组)之底的传统划法。  相似文献   

2.
江苏中部宝应地区晚泥盆世——早石炭世孢子组合   总被引:9,自引:4,他引:5  
本文首次研究了苏中宝应地区应2井泥盆—石炭系过渡层的孢子组合,共33属51种,包括7新种,由老至新确定LH和DM两个孢子组合带,分别可与龙潭、句容五通组上部擂鼓台段的两个带以及国外相应带对比;LH带属晚泥盆世末期(Fa2d—Tnla),DM带属早石炭世早期(Tn1b晚期—Tn2)。根据孢子层序研究,肯定井下白垩系之下的地层是倒转的。  相似文献   

3.
新疆三塘湖盆地塘参1井晚侏罗世齐古组孢粉组合   总被引:1,自引:0,他引:1  
黄嫔  徐晓山 《古生物学报》2004,43(2):262-280
研究的孢粉化石发现于新疆三塘湖盆地塘参 1井齐古组 (井深 95 5— 1 2 38m) ,共计 5 3属 1 30种 (包括1新属 :Santanghusporitesgen .nov .和 6新种 ) ,其中蕨类植物孢子 2 4属 4 0种 ,裸子植物花粉 2 9属 90种。组合以高含量的Classopollis、丰富的松柏类花粉及含少量早白垩世的分子为特征。根据孢粉组合特征 。  相似文献   

4.
记述了广西横县六景那高岭组、郁江组,武宣二塘二塘组和象州大乐四排组(大乐组)的无颌类和鱼类微体化石。经过形态学和古组织学的研究,这些化石被归于13属(其中包括1新属、2未定属)11种(其中包括3新种4未定种和1比较种)。结合以往在莲花山组和那高岭组下部已报道的脊椎动物大化石资料讨论了广西中部下泥盆统的脊椎动物组合序列:莲花山组以Yunnanolepis-Qujinolepis组合,那高岭组以Asiaspis expansa-Machaeracanthus? bohemicus组合,郁江组以Turinia sp.-Cheiracanthoides comptus-Ohiolepis newberryi组合,二塘组以Nostolepis guangxinensis-Wuxuanichthys wangi-Ligulalepis cf. toombsi组合为代表。另外,据已报道的脊椎动物微体化石和大化石资料,对广西中部和云南东部下泥盆统进行了对比。  相似文献   

5.
根据东河塘组的原始定义、井下孢子化石组合以及与下伏克孜尔塔格组和上覆巴楚组的相变关系,本文进一步论证东河塘组具有明显穿时性,并厘定了岩相的识别标志及其在塔里木板块的3种展示类型,即3段式、2段式与1段式。早海西期(或加里东期与海西期)构造运动不整合面作为东河塘组之底界,巴楚组底界为含砾砂岩段(或泥岩段)之底,东河塘组与巴楚组之间在多个地点表现为角度不整合式的超覆,仅西部的巴楚局部地点可见两组之间为整合或平行不整合接触。据新井所获得的丰富孢粉化石,可将东河塘组划分出两个孢子组合,即下部的Apiculiretusispora hunanensis-Aneurospora tarimensis(HT组合)和上部的Ancyrospora furcula-Cymbosporites tarimensis(FT组合),时代主要归属于晚泥盆世法门中期,泥盆-石炭系界线可置于巴楚组下泥岩段中部的碳酸盐岩夹层之顶。  相似文献   

6.
湘中锡矿山邵东组和孟公坳组共产小孢子45属83种(含10个新种,3个新联合),可划分为4个孢子组合,即:Retisporalepidophyta-Apiculiretusisporafructicosa(LF)组合,Rugosporacf.flexuosa-Retisporalepidophyta(FL)组合,LophozonotriIetesexcisus-Retisporalepidophyta(EL)组合和Crassisporacf.kosankei-Lycosporadenticulata(KD)组合。根据孢子组合的特征,泥盆-石炭系界线置于EL与KD组合之间,即相当于孟公坳组中下部与上部之间。  相似文献   

7.
作者系统研究了新疆乌鲁木齐郝家沟剖面郝家沟组、八道湾组的孢粉化石,共计98属300种(包括2新属4新种)。根据孢粉属种组成及其含量的变化,自下而上分为5套组合:1.Concavisporites-Dictyophyllidites-Chas-matosporites-Cycadopites组合(组合1),2.Cyathidites-Deltoidospora-Chasmatosporites-Cycadopites组合(组合2),3.Cyathidites-Brevilaesuraspora-Chasmatosporites-Cycadopites-Perinopollenites组合(组合3),4.Cyathidi-tes-Osmundacidites-Pinuspollenites-Piceites-Perinopollenites组合(组合4),5.Cyathidites-Contignisporites组合(组合5)。依据组合中一些重要分子的地质时限讨论及其与相关组合的对比,将组合1归为晚三叠世,组合2—组合4归为早侏罗世早期,组合5归为早侏罗世晚期。并讨论了三叠系与侏罗系的界线及八道湾组的地质时代问题。文中描述孢子花粉2新属4新种,图示孢子花粉及疑源类共74属175种。  相似文献   

8.
新疆若羌石灰华中的植物化石及古环境*   总被引:9,自引:3,他引:6  
根据首次从富阳西湖组发现的孢子及其垂直分布特征,划分出下段 LH 组合和上段 DP 组合,分别归入晚泥盆世法门晚期(斯图年期)和早石炭世早期(杜内早期),即泥盆-石炭系界线通过西湖组内部,与江苏五通组类似.  相似文献   

9.
鄂尔多斯盆地西缘中石炭世介形类   总被引:2,自引:1,他引:1  
本文报道了鄂尔多斯盆地西缘,桌子山、贺兰山地区中石炭统羊虎沟组介形类化石10属27种(包括9新种、2未定属种)。化石保存较好,分带明显。自下而上划分了三个组合:Bairdia-Microcheilinella组合Ⅰ;2.Healdio-Bythocypris组合Ⅱ;3.Healdia-Paraparchites组合Ⅲ.化石除地方种外,可与美国南半部密苏里、俄克拉荷马、得克萨斯等诸州之石炭系中所见介形类大致可以对比。  相似文献   

10.
王念忠 《古生物学报》1992,31(3):280-303
记述了广西横县六景那高岭组、郁江组,武宣二塘二塘组和象州大乐四排组(大乐组)的无颌类和鱼类微体化石。经过形态学和古组织学的研究,这些化石被归于13属(其中包括1新属、2未定属)11种(其中包括3新种4未定种和1比较种)。结合以往在莲花山组和那高岭组下部已报道的脊椎动物大化石资料讨论了广西中部下泥盆统的脊椎动物组合序列:莲花山组以Yunnanolepis-Qujinolepis组合,那高岭组以Asiaspis expansa-Machaeracanthus? bohemicus组合,郁江组以Turinia sp.-Cheiracanthoides comptus-Ohiolepis newberryi组合,二塘组以Nostolepis guangxinensis-Wuxuanichthys wangi-Ligulalepis cf. toombsi组合为代表。另外,据已报道的脊椎动物微体化石和大化石资料,对广西中部和云南东部下泥盆统进行了对比。  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.
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   

15.
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   

16.
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   

17.
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   

18.
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   

19.
Oral cancer is one of the main causes of cancer-related deaths in South-Asian countries. There are very limited treatment options available for oral cancer. Research endeavors focused on discovery and development of novel therapies for oral cancer, is necessary to control the ever rising oral cancer related mortalities. We mined the large pool of compounds from the publicly available compound databases, to identify potential therapeutic compounds for oral cancer. Over 84 million compounds were screened for the possible anti-cancer activity by custom build SVM classifier. The molecular targets of the predicted anti-cancer compounds were mined from reliable sources like experimental bioassays studies associated with the compound, and from protein-compound interaction databases. Therapeutic compounds from DrugBank, and a list of natural anti-cancer compounds derived from literature mining of published studies, were used for building partial least squares regression model. The regression model thus built, was used for the estimation of oral cancer specific weights based on the molecular targets. These weights were used to compute scores for screening the predicted anti-cancer compounds for their potential to treat oral cancer. The list of potential compounds was annotated with corresponding physicochemical properties, cancer specific bioactivity evidences, and literature evidences. In all, 288 compounds with the potential to treat oral cancer were identified in the current study. The majority of the compounds in this list are natural products, which are well-tolerated and have minimal side-effects compared to the synthetic counterparts. Some of the potential therapeutic compounds identified in the current study are resveratrol, nimbolide, lovastatin, bortezomib, vorinostat, berberine, pterostilbene, deguelin, andrographolide, and colchicine.  相似文献   

20.
We report 19 new species records for the faunal list of Coleoptera in New Brunswick, Canada, six of which are new records for the Maritime provinces, and one of which is new Canadian record. We also provide the first recent records for five additional species in New Brunswick. One new species of Stenotrachelidae, Cephaloon ungulare LeConte, is added to the New Brunswick faunal list. Additional records are provided for Cephaloon lepturides Newman, as well the first recent record of Nematoplus collaris LeConte. Two species of Oedemeridae, Asclera puncticollis (Say) and Asclera ruficollis (Say), are newly reported for New Brunswick, and additional locality and bionomic data are provided for Calopus angustus LeConte and Ditylus caeruleus (Randall). The records of Ditylus caerulus are the first recent records for the province. Three species of Meloidae, Epicauta pestifera Werner, Lytta sayi LeConte, and Meloe augustcollis Say are reported the first time for New Brunswick; Epicauta pestifera is newly recorded in Canada. Lacconotus punctatus LeConte and the family Mycteridaeis newly recorded for New Brunswick. The first recent records of Borus unicolor Say (Boridae) are reported from the province. One new species of Pythidae, Pytho siedlitzi Blair, and the first recent records of Pytho niger Kirby are added to the faunal list of New Brunswick. Three species of Pyrochroidae are newly reported for the province, including Pedilus canaliculatus (LeConte) and Pedilus elegans (Hentz), which are new for the Maritime provinces. Five species of Anthicidae and the first recent record of Anthicus cervinus LaFerté-Sénectére are newly reported for New Brunswick. Anthicus melancholicus LaFerté-Sénectère, Sapintus pubescens (LaFerté-Sénectère), Notoxus bifasciatus (LeConte), and Stereopalpus rufipes Casey are new to the Maritime provinces faunal list. Ambyderus granularis (LeConte) is removed from the faunal list of the province. Three species of Aderidae, Vanonus huronicus Casey, Zonantes fasciatus (Melsheimer), and Zonantes pallidusWerner, are newly recorded for New Brunswick; Zonantes fasciatus and Vanonus huronicus are new for the Maritime provinces' faunal list. Collection data, bionomic data, and distribution maps are presented for all these species.  相似文献   

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