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洛川黄土纳米尺度观察：纳米棒状方解石 总被引：6，自引：0，他引：6
本文对洛川黄土剖面典型样品进行了透射电镜分析，发现黄土中存在纳米棒状方解石。此类方解石直径30～50nm，长度几百纳米至几微米。纳米棒状晶体有圆滑地粗细变化和弯曲现象，偶见晶体连接成树枝状或晶体直角连接形成框架状形态。X-射线能谱分析显示方解石有少量的镁、磷和硫，这种纳米棒状方解石在国内外文献中鲜有报道。根据纳米尺度研究结果推测，这种纳米棒状方解石形成与生物衍生物诱导的定向结晶有关。纳米棒状方解石是一种重要的黄土堆积时期干旱环境指示矿物，其碳、氧稳定同位素组成代表黄土堆积时气候参数。纳米棒状方解石的发现，对环境中纳米矿物研究、黄土中碳酸盐碳成因及古气候研究具有重要价值。 相似文献
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Based on the principle of synthesis, a new method was put forward to dispose Congo Red anion-containing dyestuff from wastewater and its feasibility was also examined. The principle of the method is described as follows： Mg^2＋ and Al^3＋ are hydrolyzed to form Mg/Al-LDH by adding Mg^2＋, Al^3＋ and NaOH in wastewater containing anion dyestuff, which is selectively intercalated with the interlayer of LDH in order to balance positive structural charge. While Mg^2＋ and Al^3＋ are co-precipitated to form LDH, the anion dyestuff in wastewater will be removed by LDH synthesized in-situ, as is confirmed by X-ray diffraction analysis of settlings and chemical analysis of aqueous samples. In this work, we studied the influence of Mg/Al mole ratio, pH value, time and temperature of reaction on the removal of anion dyestuff and the use of Mg and Al. The experimental results showed the maximum removal efficiency of anion dyestuff could be attained when pH value was 9.0, and Mg/Al mol ratio was 2 ： 1, reaction duration was 2 hours, and the effect of temperature was not remarkable, and the removal efficiency could reach 100%. Meanwhile, the Mg and Al added could be made good use of. This technology has the advantage of extraordinary efficiency of wastewater disposal. 相似文献
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CHEN Gang QING Chengsong CHEN Tianhu LI Xiaoxuan SONG Yinxian PENG Shuchuan 《《地质学报》英文版》2006,80(2):257-261
Decoloration of acidic scarlet GR by pyrolusite is studied in this paper. The effects of pH in solution, dosage and granularity of pyrolusite, reaction temperature, and vibration speed on decoloration efficiency are discussed. According to experiment results, the decoloration efficiency may exceed 95% for 40 mg/L GR solution by pyrolusite. pH is most important among all factors which impact the decoloration of acidic scarlet GR. Dosage and granularity of pyrolusite, reaction temperature, and vibration speed have a little benitfit on decoloration. The high decoloration efficiency and low removal efficiency of COD as well as FT-IR spectra of products between pyrolusite and acidic scarlet GR indicate that acidic scarlet GR undergoes the redox reaction on the interface of mineral and its chromophore is oxidated and decolored, but it is not removed thoroughly by oxidation. 相似文献
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XU Liang XIE Qiaoqin CHEN Tianhu XU Xiaochun ZHOU Yuefei SUN Shaohu CHEN Ping 《《地质学报》英文版》2020,94(6):1849-1859
Colloform pyrite (CPy) is widely distributed in the Tongling mineralization cluster of the Middle–Lower Yangtze River Mineralization Belt (MLYRMB), China. There have many debates as to whether such CPy is associated with Late Mesozoic igneous or Carboniferous sedimentation. CPy from the Xinqiao deposit, a representative of the stratabound sulfide deposits in the MLYRMB, was studied by powder X-ray diffraction (XRD), field-emission scanning electron microscopy (SEM), and high-resolution transmission electron microscopy (TEM). The results show that CPy mainly comprises pyrite, pyrrhotite, quartz, and illite. Pyrite in CPy shows cubic, globule, and xenomorphic morphologies. No octahedral or pyritohedron was observed. Most of the quartz crystals display xenomorphic morphology, where pyrite mold are popular on the surface. Organic matter (OM), which is usually bound to illite, is an important component in CPy. Morphological investigations which exhibit detrital features of quartz and clay minerals indicate that they were derived from continental weathering. Specially, some hexagonal pyrrhotite nanoparticles which show mackinawite morphology are coexisted with OM. The results indicate that the transformation process of sulfides possibly is mackinawite (the precursor)—hexagonal pyrrhotite—pyrite. Thus, compositional and micro-textural characteristics of CPy in Xinqiao deposit suggest it to be a sedimentary origin rather than a hydrothermal origin which is associated with Yanshanian magmatism. Moreover, the coexistence of CPy and stratabound sulfide orebodies in the MLYRMB suggests a causal link between the two. It is considered that CPy might have served as a Cu mineralization geochemical barrier for the Cu-bearing ore-forming fluids, which originated from the Mesozoic magma in the MLYRMB. 相似文献
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兰坪盆地水泄铜(钴)矿床石英的40Ar-39Ar快中子活化年龄 总被引：2，自引：2，他引：0
选取水泄铜(钴)矿床主成矿阶段的石英样品进行40Ar-39快中子活化法同位素地质年龄测定,获得坪年龄59.2±0.8Ma,对应的等时年龄为59.8±0.5Ma,反等时线年龄为59.9±0.1Ma,三者在误差范围内完全一致,都可代表矿石的形成年龄。该年龄与兰坪盆地铜多金属矿集区的矿床形成时代一致,反映包括水泄铜(钴)矿床在内的区域矿床形成于喜马拉雅造山运动早期统一的构造地质背景之下,受同一期构造—热演化事件的制约。 相似文献
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基于CWRF模式结果,探讨了6种边界层参数化方案对30 a东亚近海热带气旋的强度、频数及路径模拟的可能影响。结果发现：CWRF模式中各边界层参数化方案模拟的热带气旋频数普遍较观测偏少,模拟强度相比观测也均偏弱。热带气旋的强度、频数及出现频次的空间分布对模式边界层方案的选取较为敏感。CAM3方案模拟强热带气旋的能力较其他方案偏好,ACM方案在多数年份模拟的热带气旋个数偏多,且在不同月份模拟的热带气旋生成频率与观测最接近,CAM3方案模拟的热带气旋出现频次与观测的偏差在大部分地区偏小。综合来看,CWRF模式中边界层参数化选用CAM3方案模拟热带气旋活动的性能较好。 相似文献
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为了探索高寒草甸土壤理化性质对海拔和坡向的响应及其与植被的关系,以东祁连山高寒草甸为研究对象,分析了7个海拔和2个坡向高寒草甸的土壤养分含量和生态化学计量比变化规律及其与植被的关系。结果表明：（1） 土壤含水量、电导率、有机碳、全氮、全钾、碱解氮、速效磷、速效钾含量、碳磷比（C/P）和氮磷比（N/P）随海拔的升高呈先升高后降低的趋势,土壤容重、全磷和碳氮比（C/N）呈先降低后升高的趋势。（2） 同一海拔,大部分海拔梯度阳坡的土壤土壤容重、速效钾、电导率和全磷高于阴坡,阳坡的土壤含水量、速效磷、C/P和N/P低于阴坡,海拔3200 m梯度以下阳坡的土壤有机碳、全氮、碱解氮和C/N低于阴坡。（3） 不同海拔和坡向的高寒草甸土壤C/N、C/P和N/P处于14.55~38.13、12.61~87.94和0.27~5.01之间。（4） 冗余分析（RDA）发现,土壤容重、全氮和速效磷是影响高寒草甸植被的关键土壤因子,聚类分析发现海拔3200~3400 m的阴坡和阳坡聚为一类。综上所述,东祁连山高寒草甸土壤养分和生态化学计量比随海拔和坡向的变化呈规律性变化,基于对N/P比的分析发现,该区域高寒草甸类草原的初级生产力主要受土壤氮限制且低海拔和高海拔区域尤为明显,基于聚类分析发现,海拔3000 m和3400 m是该区域草地植被和土壤特征发生变化的临界线。建议在高寒草甸类草原的管理过程中,应该充分考虑海拔和坡向的分异性特征。 相似文献