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91.
采用溶液插层法,利用壳聚糖和蒙脱土制备了壳聚糖/蒙脱土插层复合物,使用红外光谱和X-射线衍射分析对其结构进行了表征;以此复合物为活性红染料RR136的吸附剂,考察了复合物中壳聚糖与蒙脱土的摩尔比、染料溶液pH值和浓度、吸附温度及吸附剂用量等因素对吸附性能的影响。结果表明,吸附反应的最佳条件是以壳聚糖与蒙脱土摩尔比为5∶1的插层复合物为吸附剂,反应温度20℃,RR136溶液pH为3。壳聚糖/蒙脱土插层复合物对活性红染料的吸附更符合Langmuir模型,吸附热力学参数ΔGo、ΔHo和ΔSo值分别为-3.338kJ·mol-1(30℃),-37.98kJ·mol-1和-114.77J·mol-1·K-1,表明壳聚糖/蒙脱土插层复合物对活性红染料的吸附是自发的、以物理吸附为主的放热反应。  相似文献   
92.
The Jinping–Fan Si Pan (JFP) Cenozoic magmatic and Cu–Mo–Au metallogenic belt in the southeastern part of the Ailao Shan shear zone host the Tongchang, Chang′an, Habo, and Chinh Sang Cu–Mo–Au deposits. These deposits form an integrated epithermal-porphyry regional mineralization system associated with 40–32 Ma high-K alkaline magmatism. The magmatic rocks in the belt have relatively low TiO2 (<0.73 wt%), P2O5 (<0.29 wt%), and FeO* (<4.99 wt%), and high Na2O (2.86–4.75 wt%) and K2O (4.01–7.98 wt%). They also have high contents of incompatible trace elements, and are enriched in LILE (Rb, Ba, K, Sr) and LREE. They have marked Nb, Ta, Ti and P depletion in primitive mantle-normalized spidergrams, and plot close to the EMII mantle field in the Sr–Nd isotopic diagram. These characteristics are similar to those of the Eocene high-K alkaline rocks along the northern Ailao Shan belt, eastern Tibet plateau. The sulfur and lead isotope analyses of sulfide minerals from both the ores and related magmatic rocks confirm the involvement of a magmatic ore fluid. The Cenozoic alkaline intrusions and Cu–Mo–Au mineralization in the JFP were formed prior to the initiation of left-lateral shearing along the Ailao Shan shear zone. The magmas appear to have been derived from enriched mantle, possibly with mixing of materials from the buried Tethyan oceanic lithosphere, and/or crust.  相似文献   
93.
We have observed the Red Rectangle nebula with the Multi-Object Spectrograph on the WIYN telescope. Moderate-resolution spectra (Δ λ =0.4 Å) in the region of 5800 Å were obtained in 3-arcsec apertures at over 50 positions in the nebula. Accurate and precise wavelength calibrations were obtained against a thorium–argon lamp and the sodium lines in the sky and nebula. The peak position and full width at half-maximum of the 5800-Å Red Rectangle band (RRB) were measured to beyond 15 arcsec from the star. The shortest wavelength of the band is found to be 5799.10±0.15 Å in the rest frame of the nebula. None of the emission bands has intensity coincident with the wavelength of the diffuse interstellar band (DIB) at 5797.11±0.05 Å. The 2-Å offset cannot be explained by an instrumental, spectroscopic or photophysical effect. The hypothesis that the same molecule may be the carrier of the RRB and the DIB is contradicted by these observations. As a further test of the hypothesis, absorption has been sought that would be due to a potential DIB carrier in the nebula. Tentative evidence for absorption is found in the RRB spectra taken within 9 arcsec of the star; but any absorption has a peak position essentially coincident in wavelength with the band maximum of the emission band.  相似文献   
94.
The Red Hills peridotite in the Dun Mountain ophiolite of SouthIsland, New Zealand, is assumed to have been produced in a paleo-mid-oceanridge tectonic setting. The peridotite is composed mostly ofharzburgite and dunite, which represent residual mantle andthe Moho transition zone (MTZ), respectively. Dunite channelswithin harzburgite blocks of various scales represent the MTZcomponent. Plagioclase- and clinopyroxene-bearing dunites occursporadically within common dunites. These dunites representproducts of melt–wall-rock interaction. Chondrite-normalizedrare earth element (REE) patterns of MTZ clinopyroxenes showa wide compositional range. Clinopyroxenes in plagioclase dunitesare extremely depleted in light REE (LREE) ([Lu/La]N >100),and are comparable with clinopyroxenes in abyssal peridotitesfrom normal mid-ocean ridges. Interstitial clinopyroxenes inthe common dunite have flatter patterns ([Lu/La]N 2) comparablewith those for dunite in the Oman ophiolite. Clinopyroxenesin the lower part of the residual mantle harzburgites are evenmore strongly depleted in LREE ([Lu/La]N = 100–1000) thanare mid-ocean ridge peridotites, and rival the most depletedabyssal clinopyroxenes reported from the Bouvet hotspot. Incontrast, those in the uppermost residual mantle harzburgiteand harzburgite blocks in the MTZ are less LREE depleted ([Lu/La]N= 10–100), and are similar to those in plagioclase dunite.Clinopyroxenes in the clinopyroxene dunite in the MTZ are similarto those reported from mid-ocean ridge basalt (MORB) cumulates,and clinopyroxenes in the gabbroic rocks have compositions similarto those reported from MORB. Strong LREE and middle REE (MREE)depletion in clinopyroxenes in the harzburgite suggests thatthe harzburgites are residues of two-stage fractional melting,which operated initially in the garnet field, and subsequentlycontinued in the spinel lherzolite field. The early stage meltingproduced the depleted harzburgite. The later stage melting wasresponsible for the gabbroic rocks and dunite. Strongly LREE–MREE-depletedclinopyroxene in the lower harzburgite and HREE-enriched clinopyroxenein the upper harzburgite and plagioclase dunite were formedby later reactive melt migration occurring in the harzburgite. KEY WORDS: clinopyroxene REE geochemistry; Dun Mountain ophiolite; Moho transition zone; orogenic peridotite; Red Hills  相似文献   
95.
依据在湖北武汉古姆山志留系浅海红层中新发现的古鱼类化石,确证了兰多维列统特列奇阶下部红层——志留系下红层在鄂东南地区广泛存在,并在前人工作基础上对武汉地区原坟头组进行了重新厘定,将其一分为二,上部仍为坟头组,下部则称清水组。新厘定后的坟头组以黄绿色、灰绿色、灰黄色泥岩、泥质粉砂岩、粉砂岩为主,富含腕足类、双壳类、腹足类、三叶虫和遗迹化石; 清水组下部以紫红色、红褐色泥岩、泥质粉砂岩为主,夹少量石英砂岩,上部以紫红色、黄绿色石英砂岩为主,夹泥岩、泥质粉砂岩、粉砂岩。在清水组上部新发现的鱼类化石包括盔甲鱼类锅顶山汉阳鱼(Hanyangaspis guodingshanensis)、意外洪山鱼(Hongshanaspis inexpectatus)、后棘江夏鱼(Jiangxialepis retrospina)及软骨鱼类中华棘鱼(Sinacanthus)、新中华棘鱼(Neosinacanthus)。这些新发现的古鱼均为张家界脊椎动物群温塘鱼类化石组合中的成员,其中,后棘江夏鱼可以跟产自江西武宁地区下红层清水组中的九江江夏鱼(J. jiujiangensis)直接对比,二者同属于真盔甲鱼目曙鱼科江夏鱼属,而曙鱼科成员则可以作为志留系下红层的标志性分子。根据鱼群面貌和地层层序,武汉地区的志留系下红层可以与皖、苏地区的侯家塘组、浙西北地区的唐家坞组、赣西北地区的清水组、湘西北地区的溶溪组以及新疆塔里木地区的塔塔埃尔塔格组进行很好的对比,其时代为志留纪兰多维列世特列奇期早期。华南板块志留系下红层的分布特征表明, 在特列奇期早期,上、下扬子海之间存在一狭长的浅海区域,这为盔甲鱼类在湖北武汉和江西武宁两地之间的扩散与交流提供了便利条件和可能。  相似文献   
96.
孙崇波  李敏同  李俊  周洪兵  陈晓东 《地质论评》2023,69(2):2023020007-2023020007
笔者等通过对哀牢山—红河剪切带5件砂岩磷灰石样品裂变径迹分析,获得测试分析样品的表观年龄,对所有样品利用模拟退火法进行了热史模拟,取得其热演化史;得出哀牢山—红河剪切带在新生代发生了相似的构造演化过程,其经历了2次快速冷却剥露事件,分别发生在37~14 Ma和5. 1~0 Ma,平均冷却速率分别为3. 98℃/Ma和11. 15℃/Ma;在发生快速冷却的时间上,存在自东向西逐渐变晚的趋势,说明哀牢山—红河剪切带在新生代可能为自东向西的幕式隆升。  相似文献   
97.
新生代C4植被开始扩张的年代、过程和驱动机制是全球古气候变化研究的焦点问题.中国黄土高原的黄土-红粘土剖面保存了连续的古生态演化记录,是研究这一关键科学问题的理想载体.本文选择黄土高原北部佳县厚达64m的红粘土剖面(8.2~2.7Ma),对190个层位的次生方解石矿物进行了无机碳同位素测试,由此分析了晚中新世-上新世末的C4植被扩张和演化过程.C4植被持续增长与全球冰盖的扩张基本一致,表明气候变冷很可能导致了黄土高原区域气候的干旱化与降雨季节性的增强.C4植被的扩张存在明显的3个阶段,分别以6.6Ma和3.6Ma为界限,每一次扩张增加10%左右,暗示了全球性的构造事件对黄土高原植被演化的控制.此外,佳县红粘土剖面呈现10次持续时间为10 ~ 20万年的碳同位素正漂移事件,平均每40万年发生一次,说明40万年轨道周期也控制着C4植被的演化.  相似文献   
98.
张辉  徐九华  成曦晖 《地质通报》2015,34(6):1011-1025
美国阿拉斯加红狗(Red Dog)铅锌矿床为典型的喷流沉积型(SEDEX)或页岩容矿矿床,拥有世界上最丰富的锌储量。矿床赋存于石炭纪库纳组中。该地层由黑色富有机质的硅质泥岩和页岩组成,局部有大量的碳酸盐浊积岩。根据闪锌矿结构和成分变化,矿化可分为4个阶段:早期褐色闪锌矿阶段、黄褐色闪锌矿阶段、红褐色闪锌矿阶段和晚期棕褐色闪锌矿阶段,其中第2和第3阶段为主矿化阶段。成矿年代学及古地磁研究表明,矿化作用与库纳组沉积作用同时发生,且存在中生代热液叠加。矿床形成经历了4个沉积-热液成矿过程:未固结泥中重晶石和硫化物沉积、重晶石的热液重结晶和硫化物沉淀、重晶石和硫化物脉的形成并交代早期重晶石,以及晚期角砾岩-细粒石英和晚期棕褐色闪锌矿的形成。  相似文献   
99.
In recent years, several studies focused on the detection of hydrocarbon pollution in the environment using hyperspectral remote sensing. Particularly the indirect detection of hydrocarbon pollution, using vegetation reflectance in the red edge region, has been studied extensively. Bioremediation is one of the methods that can be applied to clean up polluted sites. So far, there have been no studies on monitoring of bioremediation using (hyperspectral) remote sensing. This study evaluates the feasibility of hyperspectral remote sensing for monitoring the effect of bioremediation over time. Benzene leakage at connection points along a pipeline was monitored by comparing the red edge position (REP) in 2005 and 2008 using HyMap airborne hyperspectral images. REP values were normalized in order to enhance local variations caused by a change in benzene concentrations. 11 out of 17 locations were classified correctly as remediated, still polluted, or still clean, with a total accuracy of 65%. When only polluted locations that were remediated were taken into account, the (user's) accuracy was 71%.  相似文献   
100.
This paper combines labour history and labour geography through an analysis of the making of labour demands in Glasgow during the early twentieth century. The paper asserts how revisiting histories such as Red Clydeside reveals complexities within labour movements and links to more recent debates within labour geography. Archival research provides a relational account of the place-based politics of Glasgow that emerged during the forty hours movement in 1919. This allows the paper to juxtapose the broader international linkages forged by Scottish workers alongside racialised hostilities within the city. In particular, the paper compares and contrasts the progressive internationalism of the strike newspaper with the Broomielaw race riot between local and foreign sailors during the same month as the strike. This comparison also raises the longer-term trajectories of labour grievances to foreground the ambivalent and contested nature of labour demands, identities and histories. In particular, the paper pays close attention to contrasting practices of labour internationalism emerging from the relevant archives. This historical approach makes a broader contribution to debates within labour geography by engaging with the complexities and tensions of labour organising and demand making.  相似文献   
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