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1.
Images of the velocity cross--section at 10 different depths in Yunnan Province have been suc-cessfully reconstructed, using the principle and method of seismic tomography (ST). These velocitycoss-sections are consistent with the results of six velocity profiles of deep seismic sounding. The reconstruction method of ST used in this paper has two advantages: (i) The velocity modeli determined by spe cifying node--velocities of hexahedron and linear interpolation through knownbasic function. A velocity field with lateral continuous velocity value and vertical discontinuitiesis established. This model is obviously better than the block model of constant velocity. The verticaldiscontinuities allow the model to simulate velocity discontinuities in the crust and upper mantle. (ii)The velocity and hypocenter parameters are separated by introducing an orthogonal projection oper-ator. Sequential orthogonal triangularization and modified singular decomposition are adopted.These measures reduce the RAM requirement  相似文献   

2.
本文研究云南宝秀盆地一个钻孔不同深度的泥炭和褐煤抽出物芳烃馏分中多环芳烃的组成。用GC和GC/MS鉴别了它们的组份,结果表明,从双环和三环单芳构化、双芳构化、三芳构化到四环双芳构化、三芳构化及四芳构化和五环单、双芳构化、三芳构化、四芳构化以及C环开裂的萜类化合物均有不同含量的存在,这说明在煤化过程早期芳构化就进行到相当的深度,也说明云南陆源高等植物,尤其是喜温树类的造煤物种为宝秀盆地提供了特殊的芳构化有机组成系列。  相似文献   

3.
Magnetostratigraphic studies of 112 cores specimens (249 samples) in a Precambrian-Cambrian section at Meishucun, Jinning County, Yunnan Province reveal the following: (ⅰ) Around the Sinian-Cambrian boundary in the Meishucun section existed a mixed polarity zone in which the Meishucun fauna went through an evolution of appearance—flourish—extinction. (ⅱ) The Meishucun section had a paleolatitude of no more than 20° during the Sinian-Cambrian, The phosphate deposits in this region and in the Zhongyicun Member were formed in the low-latitude environments.  相似文献   

4.
Investigation on the meteorite of Boxian, Anhui Province, China has been performed through transparent and opaque minerals, chondrules, Mssbauer spectra, thermoluminescence, chemical composition, isotopic chronology, inclusion, mechanical and paleomagnetic character, etc. The meteorite has 16 transparent and 12 opaque minerals, including a new mineral named Zhanghengite. The meteorite belongs to the chemical group of LL and the transitional rock type of 3—4. The principal textures of chondrules, the formation and evolution of the meteorite have also been studied and discussed.  相似文献   

5.
研究表明,不同粒度的红辉沸石在不同的温度条件下对K^ 、Na^ 、Ca^2 、Mg^2 、NH4^ 等离子具有不同的吸附容量。在30℃时,8μm的红辉沸石对K^ 、Na^ 、Ca^2 、Mg^2 、NH4^ 的吸附量分别为:10.90mg/g、10.01mg/g、7.64mg/g、5.50mg/g、108.70mmol/100g;45μm的红辉沸石对K^ 、Na^ 、Ca^2 、Mg^2 、NH4^ 的吸附量分别为:10.10mg/g、9.80mg/g、6.90mg/g、5.08mg/g、101.10mmol/100g;246μm的红辉沸石对K^ 、Na^ 、Ca^2 、Mg^2 、NH4^ 的吸附量分别为:2.66mg/g、2.20mg/g、1.86mg/g、1.26mg/g、28.00mmol/100g;在2℃时,8μm的红辉沸石对K^ 、Na^ 、Ca^2 、Mg^2 、NH4^ 的吸附量分别为:10.60mg/g、9.82mg/g、6.90mg/g、5.07mg/g、99.60mmol/100g。在常温25-30℃,湿度82%条件下,246μm、45μm、8μm的红辉沸石含水率为7.06%、7.25%、7.78%。  相似文献   

6.
The geochemistry of the main country rocks of gold deposits in Shaoxing-Longquan uplift region has been systematically studied in this paper. The authors believe that the Proternzoic Shuangxiwu group is the primary gold-bearing formation in this region and the Sinian-Cambrian Chencai group and the Precambrian Zuoxi migmatized quartz-diorite are the derivative gold-bearing formations. The genesis of rocks, content distribution features of gold and silver, characteristics of associated trace elements and other geochemical features in these formations clearly show a relationship of inheritance with evolution. By means of metamorphic-solution and volcanic-solution or/and other geological actions, these gold-bearing formations supplied the necessary ore-forming materials for the gold deposits in this region.  相似文献   

7.
It is considered that the early Jinning period granitoids from southern Anhui Province belong to the continental crust transformation (S) type and have their own characteristics which are different from those for general continental crust transformation type granitoids. They were formed at the early stage of the late Proterozoic era when that region was at an island-arc stage of the continental margin environment. By that time the continental crust was just formed and had a nature of juvenile crust. It is this juvenile crust that determined a series of characteristics of that type granitoids and made them a relatively independent rock type. They are the products formed by the continental crust in a certain stage of development.  相似文献   

8.
The blueschists in western Yunnan Province are distributed in Lancangjiang and Ailaoshan metamorphic belts and occur as interlayer in green schist and mica schist. Their protolith is basaltic and pelitic rocks with a mineral assemblage of Cr (or Win)+Ab+Qz+Chl+Ph+Ep+Sph+Act and Gl+Ph+Tc+Ep+Alm+Qz+Do, respectively. The P-T conditions of blueschist metamorphism range from 170—443℃ at c. 4—6. 7 kbar. The origin of blue schist of the Lancangjiang belt is related to the subduction and the close of the paleo-Tethys oceanic basin. The Ailaoshan blueschist, however, may be related to the continent continent collision and the dynamic metamorphism.  相似文献   

9.
贵州凤冈县宜茶区土壤重金属含量状况及污染评价   总被引:1,自引:0,他引:1  
对贵州凤冈县14个乡镇的宜茶土壤中汞、镉、铅、砷、铬、铜6种重金属含量进行统计分析,根据NY/T 5020-2001《无公害食品茶叶产地环境条件》、NY 5199-2002《有机茶产地环境条件》、NY/T 5295-2004《无公害食品产地环境评价准则》进行评价,为凤冈县茶园建设规划提供理论依据。  相似文献   

10.
The detailed study on petrochemistry and geochemistry shows that meta-volcanics from Huimin and meta-basalts from Suyi belong, respectively, to different volcanic series. The former is of non-alkalic volcanic series and the latter is of straddle A-type alkslic series. Based on their geochemical characteristics of REE, LIL, HFS and Nd, Sr isotope elements, we suggest that Huimin volcanics were formed in an island arc setting and Suyi basalts were formed in a back-continental arc extensive setting. These two volcanic series have not petrogenic relationship.  相似文献   

11.
山东不同产地丹参的HPLC指纹图谱-化学模式识别研究   总被引:3,自引:0,他引:3  
建立RPHPLC指纹图谱-化学模式识别评价丹参质量的方法.利用RPHPLC法测定不同产地丹参药材的指纹图谱及丹参酮ⅡAt和丹参酮的含量,采用主成分分析、系统聚类分析和逐步判别分析对指纹图谱信息进行化学模式识别研究.在主成分分析的基础上,以前4个主成分为聚类分析的指标进行系统聚类分析,取阈值为8时,所有样品可被分为4类;并建立了相应的判别函数,回判准确率100%;以此为依据,初步建立了丹参化学模式识别的评价方法.  相似文献   

12.
云南褐煤蜡氧化精制的研究   总被引:5,自引:1,他引:4  
本工作对云南潦浒、寻甸、昭通蒙旦蜡进行了脱树脂,氧化精制研究,探索国产蒙旦蜡能否经精制后满足合成改性浅色蜡的要求。实验结果表明,潦浒、寻甸两厂生产的蒙旦蜡经氧化精制不能达到完全脱色,而昭通蒙旦蜡在相同的精制条件下极易脱色,所得浅色蜡质量达到和超过国外同类产品的水平,因此昭通蒙旦蜡是生产浅色蜡的理想原料。在精制反应中,加入适量YPSO-1添加剂,对改善反应条件,产物的分离,提高得率和质量均有良好的影响。文中还讨论了潦浒、寻甸脱脂蜡经氧化精制不能完全脱色的原因  相似文献   

13.
用溶胶-凝胶法以磷钼酸(MPA)的镍盐溶液水解钛酸四丁酯制备了NiPMo/TiO2催化剂.使用ICP、 XRD、 TG-DTA、 IR、 TPD-MS和微反应技术研究了催化剂的化学组成、热稳定性、化学吸附性质和催化反应性能.杂多钼酸盐与TiO2通过O2-在TiO2表面发生了键合.在623 K下,杂多阴离子仍保持原有的Keggin结构.CO2在Lewis酸位Ni(Ⅱ)和Lewis碱位Ni-O-Mo的桥氧协同作用下生成CO2卧式吸附态Ni(Ⅱ)←O-(CO)←(O--Ni).丙烯有多种吸附态在催化剂上吸附.在563 K、 1 MPa和空速1500 h-1的反应条件下,丙烯的摩尔转化率为3.2%,产物MAA选择性为95%.  相似文献   

14.
Different approaches for the synthesis of 1-benzyloxypyrazin-2(1H)-one derivatives from simple amino acids have been investigated. A library of 33 precursors for the preparation of N-hydroxy pyrazinones was obtained in moderate to good yields.  相似文献   

15.
A general synthesis of previously unknown semicarbazone-based α-amidoalkylating reagents, 4-(tosylmethyl)semicarbazones, has been developed. The synthesis involved three-component condensation of semicarbazones of aliphatic or aromatic aldehydes with the same or other aldehydes and p-toluenesulfinic acid. The scope and limitations of this reaction were investigated. The compounds obtained were demonstrated to be an efficient α-(4-semicarbazono)alkylating agents. They were reacted with H- (sodium borohydride), O- (sodium methylate), S- (sodium phenylthiolate), N- (pyrrolidine, sodium succinimide), P- (trialkyl phosphites), and C-nucleophiles (sodium diethyl malonate) to give the corresponding products of the tosyl group substitution, 4-substituted semicarbazones, including analogues of nitrofurazone. Among the prepared compounds tested in vitro for antibacterial and antifungal activity, three nitrofuryl-containing semicarbazones exhibited high biological activities with minimum inhibitory concentration (MIC) values of 8–32 μg/mL.  相似文献   

16.
A small library of new chiral bidentate hydroxyalkyl-imidazolium salts 1 is conveniently synthesized on multi-gram scale from inexpensive and commercially available chiral pool amino acids. The corresponding carbenes, generated by deprotonation of imidazolium salts 1, in combination with palladium(II) chloride were tested in the Mizoroki–Heck coupling reaction. The most significant results in terms of yields and reactivities were achieved with low catalyst loading. The catalytic activities of these imidazolium salts were also investigated in the asymmetric addition of diethylzinc to benzaldehyde. The use of MgO nanoparticles as an additive in conjunction with these ligands played a crucial role in increasing the efficiency of these reactions.  相似文献   

17.
In the context of the preparation of camptothecin and luotonin A analogs, the synthesis of some key keto-precursors and their use in Friedländer condensation are described. This paper also focuses on the stability of these keto intermediates and emphasizes the major differences between indolizinones and pyrroloquinazolinones series. Noteworthy is also the report of some original structures isolated as by-products of some experiments.  相似文献   

18.
A new and simple synthesis of novel N-protected methyl 5-substituted-4-hydroxypyrrole-3-carboxylates, which exist in equilibrium with their 4-oxo tautomers, has been developed in two steps starting from N-protected α-amino acids. The key intermediates are enaminones, which can also be isolated, characterized, and used for the construction of other functionalized heterocycles, before they spontaneously decompose to pyrrole products. 4-Hydroxypyrroles are prone to partial aerial oxidation but can be efficiently alkylated or reduced to stable polysubstituted pyrrolidine derivatives.  相似文献   

19.
The chemoselectivity in the intramolecular CH insertion of various diazosulfonamides has been experimentally studied. The results reveal that the aliphatic 1,4-, 1,5-, or 1,6-C(sp3)?H insertions of diazosulfonamides are not accessible, while the aromatic 1,5-C(sp2)?H insertion can be realized specifically by adjusting the diazo-adjacent group. In addition, the general chemoselectivities in the intramolecular CH insertions of diazosulfonyl compounds are summarized. Generally, diazosulfones undergo both aromatic 1,5-C(sp2)?H and aliphatic 1,5- and 1,6-C(sp3)?H insertions, while diazosulfonates undergo aliphatic 1,5- and 1,6-C(sp3)?H insertions. However, diazosulfonamides only undergo aromatic 1,5-C(sp2)?H insertion.  相似文献   

20.
The Langevin paramagnetic theory can’t describe the relation between magnetization of ferrofluids and applied magnetic field. The structuralization of ferrofluids, which is considered the main influence factor of the magnetization, is regarded. The part of magnetization works is deposited when the structure is forming. This action influences the magnetization of ferrofluids directly or indirectly. On the base of the “compressing” model, the Langevin function that usually describes the magnetization of ferrofluid is modified, and a well-fitted curve is obtained. An equation of the relation between the equivalent volume fraction after being “compressed” and the intensity of magnetic field is discovered, which approximately describes the process of magnetization. The relation between the approximate initial susceptibility and the volume fraction can be obtained from modified formula.  相似文献   

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