The first estimations of soil-radon activity near faults in Central Mongolia

Estimation of soil-radon activity, Q was first carried out for faults in Central Mongolia. Eight study sites were located in epicentral zones of Mogod (M = 7.8; 05 January 1967) and Avdar (M = 3.8; 22 March 2009) earthquakes, and in the vicinity of Ulaanbaatar, where small seismic events (M = 1.0–2.5) occurred in the past few years. Profile radon surveys were conducted at fifteen faults that differ in size and geodynamic activity, yet clearly topographically manifested as scarps or straightened segments of valleys of ephemeral streams.By applying the formalized method of processing of the survey results, it was possible to reveal radon anomalies and to establish that their shape, intensity and contrast are mainly determined by the structure of the fault zone. Due to heterogeneous permeability of fault zones, shapes and quantitative parameters of radon anomalies are variable at different faults and in individual cross-sections of one and the same fracture. Radon anomalies in Central Mongolia are diverse, yet the most frequent are the cases where (1) a radon anomaly is discontinuous in shape due to the presence of small domains with minimum values of Q; (2) a major part of the anomaly is located in one fault wall; and (3) a fault scarp is marked by a minimum value of Q. In Central Mongolia, intensities of radon anomalies, Q_max near neotectonic faults differ by more than an order of magnitude. The most intense anomaly (20,200 Bq/m³) is registered at Hustai fault in the vicinity of Ulaanbaatar, which indicates the importance of assessment of radon hazard for the capital city of Mongolia, where almost half the population of the country reside. The contrast of radon anomaly, K_Q is determined as a ratio of a maximum value of Q_max to a minimum value of Q_min outside the fault zone; it varies from 1.4 to 17.3 for faults of Central Mongolia. Faults characterized by ultra-high (K_Q > 10), high (10 ≥ K_Q > 5), increased (5 ≥ K_Q > 3), medium (3 ≥ K_Q > 2) and low (K_Q ≤ 2) radon activity are distinguished. A relative index, K_Q can be effectively applied for assessment of geodynamic activity of faults in Central Mongolia. On the one hand, it correlates with sizes and seismic potential of the studied faults; on the other hand, it significantly reduces the complicating influence of regional factors, such as radioactivity of rocks, sediment thickness, meteorological conditions of measurements, etc.The application of K_Q, the formalized method of detection of radon anomalies, long-distance base cross-sections, and reduction of the measurement interval near faults – these key features of the profile survey are recommendable for further more accurate estimations on the basis of the first measurements of soil-radon activity in Central Mongolia.     

Compact type-I coil planet centrifuge for counter-current chromatography

A compact type-I coil planet centrifuge has been developed for performing counter-current chromatography. It has a revolution radius of 10 cm and a column holder height of 5 cm compared with 37 and 50 cm in the original prototype, respectively. The reduction in the revolution radius and column length permits application of higher revolution speed and more stable balancing of the rotor which leads us to learn more about its performance and the future potential of type-I coil planet centrifuge. The chromatographic performance of this apparatus was evaluated in terms of retention of the stationary phase (S_f), peak resolution (R_s), theoretical plate (N) and peak retention time (t_R). The results of the experiment indicated that increasing the revolution speed slightly improved both the retention of the stationary phase and the peak resolution while the separation time is remarkably shortened to yield an excellent peak resolution at a revolution speed of 800 rpm. With a 12 ml capacity coiled column, DNP-DL-glu, DNP-β-ala and DNP-l-ala were resolved at R_s of 2.75 and 2.16 within 90 min at a flow rate of 0.4 ml/min. We believe that the compact type-I coil planet centrifuge has a high analytical potential.     

新疆茜草中铜锰铁锌钙镁的形态分析

结合新疆茜草的药用价值,用煎煮法对新疆茜草中的Cu、Mn、Fe、Zn、Ca和Mg进行了含量和形态分析.用0.45 μm滤膜分离提取液中的可溶态与悬浮态,用D101大孔吸附树脂分离可溶态中的有机态与无机态.对水煎渣依次用丙酮和盐酸提取有机态和无机态,用原子吸收光谱(AAS)法对六种元素的各个形态进行测定.结果表明:新疆茜草中各个元素的提取率在31.5%～45.2%之间,六种微量元素的相对标准偏差在0.11%～1.23%,回收率在92.5%～104.7%.     

Mathematical model of computer-programmed intermittent dual countercurrent chromatography applied to hydrostatic and hydrodynamic equilibrium systems

Dual high-speed countercurrent chromatography (dual CCC) literally permits countercurrent flow of two immiscible solvent phases continuously through the coiled column for separation of solutes according to their partition coefficients. Application of this technique has been successfully demonstrated by separation of analytes by gas–liquid and liquid–liquid two-phase systems. However, the method cannot be directly applied to the system with a set of coiled columns connected in series, since the countercurrent process is interrupted at the junction between the columns. However, this problem can be solved by intermittent dual CCC by eluting each phase alternately through the opposite ends of the separation column. This mode of application has an advantage over the conventional dual CCC in that the method can be applied to all types of CCC systems including hydrostatic equilibrium systems such as toroidal coil CCC and centrifugal partition chromatography. Recently, the application of this method to high-speed CCC (hydrodynamic system) has been demonstrated for separation of natural products by Hewitson et al. using a set of conventional multilayer coil separation columns connected in series. Here, we have developed a mathematical model for this intermittent dual CCC system to predict retention time of the analytes, and using a simplified model system the validity of the model is justified by a series of basic studies on both hydrodynamic and hydrostatic CCC systems with a computer-programmed single sliding valve. The present method has been successfully applied to spiral tube assembly high-speed CCC (hydrodynamic system) and toroidal coil CCC (hydrostatic system) for separation of DNP-amino acid samples with two biphasic solvent systems composed of hexane–ethyl acetate–methanol–0.1 M hydrochloric acid (1:1:1:1 and 4:5:4:5, v/v).     

苦马豆素全合成新进展

综述了近几十年来苦马豆素合成方法; 概括了合成苦马豆素的关键中间体, 主要包括吲哚里西啶环、二环内酰胺、环烯胺及吡喃酮化合物; 讨论了它们的反应原料、实验步骤及其收率.     

Li4Cs3B7O14: synthesis, crystal structure, and optical properties

A new noncentrosymmetric polyborate, Li(4)Cs(3)B(7)-O(14), has been synthesized using the conventional solid state reaction method. It crystallizes in the trigonal space group P3(1)21 (No. 152) with unit cell parameters of a = 6.9313(6) ?, c = 26.799(3) ?, and Z = 3. The new structure contains an infinite three-dimensional matrix that is built from B(7)O(14) building blocks rarely found in anhydrous borate compounds and LiO(n) (n = 4, 5), CsO(n) (n = 9, 10) polyhedra. The optical characterization of the compound indicates that the compound is phase matchable, and the UV cutoff edge is below 190 nm. IR spectroscopy, thermal analysis, and second-harmonic generation were also performed on the reported material.     

基于相关系数指标筛选法的油田集输泵机组用能评价体系研究

针对不同油田泵机组的用能情况不同而导致的泵机组评价指标种类和权重产生差异的问题,提出一种确定指标的方法,根据西北油田泵机组的实际工况,采用相关系数法筛选评价指标,再结合主成分分析法与灰色关联法综合评价泵机组的用能情况.结果表明筛选出了5个评价指标,按权重大小排序依次为泵机组效率、节流损失率、外输负载率、集输单耗、功率因数.通过关联度的计算,找到了能量损失严重的泵机组,并分析判断出其薄弱环节.     

红外光谱的煤精类文物材质判别方法

我国是世界上最早使用煤及煤精的国家之一,但对考古出土煤精文物的研究发现,煤精文物原材料的质地常常偏离宝石学中对有机宝石煤精的定义。在此提出“煤精类文物”的概念,将以往出土文物中如褐煤、烛煤等与煤精文物材质近似但不同的材料归至同一文化概念中。目前对于煤精类文物制品的科学研究仍存在较大空白,其中最为基础的材质种类判别也没有科学的判断方法。以陕西周原贺家墓地、陕西咸阳岩村墓地、新疆吐鲁番胜金店墓地、新疆伊犁吉仁台沟口遗址四个遗址出土的16件煤精制品和原料为研究对象,初步探索漫反射傅里叶变换红外光谱在出土煤精类文物成分分析中的应用。结果表明,不同遗址出土的煤精类文物的红外谱图有较为明显的不同,同一遗址出土的煤精类文物的红外谱图在特征波段具有相似性,不同遗址煤精类文物则差异明显。使用Norris二阶导数法对红外光谱进行处理,提高吸收峰分辨率,为精细研究提供信息,选择特殊红外光谱参数I=A_{820 cm-1}/A_{2 870 cm-1}定量分析不同样品的红外光谱,结合静水称重得到的部分样品的密度信息,对出土的煤精类文物制品材质的煤化程度初步判断。结合红外光谱特征波数的强度进一步通过主成分分析解释煤精类文物的红外光谱信息,来自不同遗址的煤精类文物样品在主成分分析得分图中得到了良好的区分,并且可以与特殊红外光谱参数I判别的初步结论互相对应。验证了以漫反射傅里叶变换红外光谱为主的无损分析方法在煤精类文物材质判别中应用的可行性;若结合不同产地煤精矿样红外光谱,则可以为煤精类文物产地判别提供研究方法。     

Cation exchange, interlayer spacing, and thermal analysis of Na/Ca-montmorillonite modified with alkaline and alkaline earth metal ions

Na-montmorillonites were exchanged with Li⁺, K⁺, Rb⁺, Cs⁺, Mg²⁺, Ca²⁺, Sr²⁺, and Ba²⁺, while Ca-montmorillonites were treated with alkaline and alkaline earth ions except for Ra²⁺ and Ca²⁺. Montmorillonites with interlayer cations Li⁺ or Na⁺ have remarkable swelling capacity and keep excellent stability. It is shown that metal ions represent different exchange ability as follows: Cs⁺?>?Rb⁺?>?K⁺?>?Na⁺?>?Li⁺ and Ba²⁺?>?Sr²⁺?>?Ca²⁺?>?Mg²⁺. The cation exchange capacity with single ion exchange capacity illustrates that Mg²⁺ and Ca²⁺ do not only take part in cation exchange but also produce physical adsorption on the montmorillonite. Although interlayer spacing d ₀₀₁ depends on both radius and hydration radius of interlayer cations, the latter one plays a decisive role in changing d ₀₀₁ value. Three stages of temperature intervals of dehydration are observed from the TG/DSC curves: the release of surface water adsorbed (36?C84?°C), the dehydration of interlayer water and the chemical-adsorption water (47?C189?°C) and dehydration of bound water of interlayer metal cation (108?C268?°C). Data show that the quantity and hydration energy of ions adsorbed on montmorillonite influence the water content in montmorillonite. Mg²⁺-modified Na-montmorillonite which absorbs the most quantity of ions with the highest hydration energy has the maximum water content up to 8.84%.