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1.
黑龙江绥滨地区晚侏罗世Buchia带*   总被引:2,自引:0,他引:2  
绥滨地区晚侏罗世东荣组的双壳类Buchia,划分为4个带:(1)晚牛津至早启莫利期的B.concentrica带;(2)晚启莫利期的B.tenuistriata带;(3)早-中伏尔加期的B.mosquensis-B.rugosa带;及(4)晚伏尔加期的B.fischeriana带。文内共描述3属9种。  相似文献   

2.
广西凤山、西林等地中三叠统上部双壳类分带研究*   总被引:7,自引:3,他引:4  
讨论广西西部中三叠统上部的双壳类生物地层序列,建立5个化石带;并附述黔南和滇东南晚三叠世1个双壳类带.这些带自下而上为:(1) Daonella (Longidaonella) producta-D. americana 带,属晚安尼早中期;(2) D. moussoni 高峰带,属晚安尼晚期;(3) D. rieberi-D. indica 带,属早拉丁期;(4) D. kotoi-D. jilongensis 带,属晚拉丁早期;(5) Halobia subcomata-D. varifurcata带,属晚拉丁晚期;(6) H. rugosoides-H. bifurcata 带,属早卡尼期.文内简要描述了各带的主要标志化石23种.  相似文献   

3.
用C—带技术识别小麦21对染色体及染色体结构变异   总被引:8,自引:2,他引:6  
钟少斌  徐杰 《遗传学报》1989,16(6):415-419
用C-带技术分析了普通小麦中国春、84001-1-33和扬麦3号的根尖染色体,结果如下:(1)除1A外,普通小麦的所有染色体均可显示出稳定的区分性带型;(2)以中国春小麦为标准建立了C-带核型;(3)对照中国春的C-带核型,发现84001-1-33的5B,7B染色体发生了相互易位,形成了重组染色体——5BS/7BS和7BL/5BL;(4)扬麦3号的1B,4B染色体与中国春明显不同,从带型上看有可能扬麦3号的1B和4B的长臂之间发生了相互交换,交换的区段包括1B,4B长臂的大部分。  相似文献   

4.
西藏北部安多地区中侏罗统(巴通阶-卡洛夫阶)菊石   总被引:1,自引:0,他引:1  
最近从藏北安多地区中侏罗统发现较丰富的菊石类化石,巴通期的菊石有OxyceritesoppeliElmi,Ho moeoplanulitescf. homoeomorphus(Buckman),H. cf. acuticosta(Roemer), Choffatiacf. vicentiMangold, Siemiradzkiacf. matisconensis(Lissajous), Proceritessp., Neuquenicerascf. yokoyamaiKobayashiandFukada和Indosphinctessp.。卡洛夫期的菊石有Oxyceritescf. subcotarius(Oppel), Macrocephalites? sp., Homoeoplanulitescf. furculus(Neumayr),Indospinctes(Elatmites) cf. reveliMangold和Reineckeitessp.。其中Indosphinctes,Indospinctes(Elatmites),Neu queniceras,Siemiradzkia和Procerites等属(或亚属)在西藏北部地区为首次报道。安多地区中—晚巴通期和早卡洛夫期菊石动物群凸现较强的地方性色彩; 晚巴通期ORBIS菊石带和早卡洛夫期KOENIGI菊石带是藏北地区菊石动物群扩散的重要时期。  相似文献   

5.
记述产自西藏南部仲巴县的一个中国目前所知最年轻的菊石群 ,含 2科 4属 6种 ,其中 4新种。据菊石群面貌和它们所产出的层位可以划分出上、下两个组合带 :上部Pachydiscuscf.hidakaensis Libycoceraszhongbaense组合带 ;下部Manambolitescujiangdingensis M .pivaeteaui组合带。产菊石的曲贝亚组的下段和上段的中、下部(82F5 0及其以下层位 )为晚Campanian期 ,上段上部 (即 82F5 2及其以上层位 )为早Maastrichtian期。  相似文献   

6.
记述产自西藏南部仲巴县的一个中国目前所知最年轻的菊石群,含2科4属6种,其中4新种。据菊石群面貌和它们所产出的层位可以划分出上、下两个组合带上部Pachydiscus.cf.Hidakaensis-Libycoceraszhongbaense组合带;下部Manambolitescujiangdingensis-M.Pivaeteaui组合带。产菊石的曲贝亚组的下段和上段的中、下部(82F50及其以下层位)为晚Campanian期,上段上部(即82F52及其以上层位)为早Maastrichtian期。  相似文献   

7.
华南东部地区晚三叠世—早侏罗世海陆交互相地层中的半咸水-海相双壳类,对于我国广泛分布的陆相上三叠统和下侏罗统的划分具有重要的意义。文中系统描述了该区晚三叠世和早侏罗世双壳类19属29种,其中Trigonucula sakawana Ichikawa,1949,Pteria sturi(Bittner,1895),Costigervillia minima Wen,1979和Cercomyapraecursor Quenstedt,1856为首次在这一区域报道;并根据新材料将前人报道的Isocardioides Fan,1962修订为Schafhaeutlia Cossmann,1897。综合这些材料和前人研究将该区小水组、三家冲组和金鸡组双壳类分别划为以下三个组合带,即Palaeopharus-Trigonucula组合带、Bakevelloides-Jiangxiella组合带和Parainoceramus-Ryderia guangdongensis组合带。文中通过对上述组合中代表属种在区域上的时代延限的分析,认为PalaeopharusTrigonucula带和Bakevelloides-Jiangxiella带的时代限于晚三叠世卡尼期(Carnian),可能延至诺利期(Norian)早期;Parainoceramus-Ryderia guangdongensis带的时代主要为早侏罗世辛涅缪尔期(Sinemurian),可能下延至赫塘期(Hettangian),上延至土阿辛期(Toarcian)。  相似文献   

8.
黑龙江东部双鸭山、集贤煤田中生代含煤地层研究*   总被引:6,自引:1,他引:5  
本文系统地讨论了黑龙江双鸭山、集贤两煤田的中生代含煤地层序列,综合各门类化石研究结果,认为海相的绥滨组和东荣组属晚侏罗世卡洛夫晚期至伏尔加期,非海相的城子河组和穆棱组属早白垩世尼坎期。文内提供11条详细的钻探剖面的生物地层资料。  相似文献   

9.
扇蕨孢子的组织培养   总被引:1,自引:0,他引:1  
1 植物名称扇蕨[Neocheiropteris palmatopedata (Baker)Christ]. 2 材料类别成熟孢子. 3 培养条件孢子萌发培养基:(1)B5 20 g·L-1蔗糖.原叶体增殖培养基:(1)B5 20 g·L-1蔗糖;(2)1/2B5 20 g·L-1蔗糖;(3)1/485 20 g·L-1蔗糖;(4)1/885 20g·L-1蔗糖;(5)B5,(6)B5 10 g·L-1蔗糖;(7)B5 30 g·L-1蔗糖;(8)B5 40 g·L-1蔗糖;(9)B5 50 g·L-1蔗糖;(10)B5 60 g·L-1蔗糖.  相似文献   

10.
西红花的离体成花   总被引:3,自引:0,他引:3  
1植物名称西红花(Crocus sativus). 2材料类别球茎的幼嫩顶芽,长度在20~30 mm. 3培养条件诱导培养基分别为:(1)MS NAA 5mg·L-1(单位下同) 6-BA 5;(2)MS NAA 5 6-BA7;(3)MS KT 5 NAA 4;(4)MS 2,4-D 2 KT0.5;(5)MS 6-BA 2 2,4-D 0.1;(6)MS 6-BA2 IBA 1;(7)B5 KT 5 IAA 4 2,4-D 1 Pro 0.5;(8)B5 KT 5 IAA 4 2,4-D 1 Pro 0.5.以上培养基均添加琼脂0.8%;(1)~(5)中加蔗糖4%,(6)中3%,(7)中6%,(8)中4%;pH 5.8.培养温度(20±2)℃,黑暗培养.  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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