丁文江的政治思想与实践——以淞沪商埠督办公署总办之任为考察中心

丁文江作为近代亦学亦政的知识分子,地质学成就已有公论,惟因为他曾就任孙传芳控制下的淞沪商埠督办公署总办,其政治思想与实践长期不为人们所关注。考察丁文江就任淞沪总办的经历,有助于我们更好地认识丁文江政治思想的特质及其局限性,也有助于我们理解当时知识分子在启蒙与救亡相交织的历史背景下如何勇于承担社会责任又勉不了政治悲剧的结局。     

玻璃中氯泡的研究

借助现代解析技术 ,在浮法玻璃板面上发现了氯泡 ,研究了氯泡的形貌及其显微结构特征 ,认为氯泡主要是来自水的污染。     

粉体接触角法快速测定长江口沉积物的表面自由焓变

根据Washburn原理研制的JF99A型粉体接触角测量仪,是利用渗透压力法测定粉体的接触角。在室温下,采用去离子水、无水乙醇、5％（m／m）的NaCl溶液、15％（V／V）的乙醇溶液为润湿液体．测定了长江口南港白龙港水域沉积物的相对接触角,从而可以确定沉积物的表面自由焓变。测定沉积物表面的润湿性疏水性质,就能反映表面上是否存在有机污染。用此方法测定具有操作简单等优点。     

Miniature differential mobility analyzer for compact field-portable spectrometers

A low-flow miniature differential mobility analyzer (mDMA) has been developed for compact field-portable mobility spectrometers to classify the submicrometer aerosol. The mDMA was designed for an ultra-low aerosol flow rate of 0.05 L/min. At a sheath flow rate of 0.2 L/min, the mDMA's upper size limit was estimated to be about 921 nm. The mDMA has a classification zone of 2.54 cm long, an outer diameter of 2.54 cm, and an inner diameter of 1.778 cm. The design allows low-cost fabrication and easy assembly. Tandem DMA measurements were carried out to evaluate the performance of the mDMA. Its transfer function was described using Stolzenburg's model. The experimentally measured transfer function shows close agreement with the theory. The transmission efficiency was comparable to that of the Knutson–Whitby DMA for particles in the range of 10–1000 nm. The mobility resolution was comparable to that of the TSI 3085 nanoDMA at the same aerosol flow rate. The design features and performance of the mDMA make it suitable for compact field portable mobility size spectrometers for measurement of nanoparticles and submicrometer aerosol.     

清水江流域总磷、氟化物污染现状分析

通过采用单因子评价法,选取2006～2009年实地监测数据,分析清水江水质现状。结果表明:清江流域总磷和氟化物总体呈降低趋势。2009年,除重安江大桥断面、湾水断面氟化物轻微超标外,其余断面均未超标,但各断面TP仍超标。     

双江油田核三段Ⅶ油组沉积微相及其储层研究

沉积微相研究是认识储层各种物性特征的重要基础。以岩心和测井分析资料为基础,通过对Ⅵ、Ⅶ油组的岩石类型及其组合、沉积构造、生物特征及粒度分布特征等沉积相标志的综合研究,确认目的层为一套扇三角洲沉积体。可进一步分为三角洲前缘及前三角洲两个亚相,其内主要发育水下分流河道、水下分流河道间、河口砂坝、远砂坝、席状砂及前三角洲泥微相。研究表明河口砂坝、水下分流河道沉积储层物性较好,远砂坝、席状砂砂体物性相对较好。反映了沉积微相对研究区储层物性特征起着重要作用。     

The Spider DMA: A miniature radial differential mobility analyzer

Abstract

The Spider differential mobility analyzer (DMA) is a novel, miniaturized radial DMA developed to provide size classification in the 10–500?nm range for applications requiring high portability and time resolution. Its external dimensions are ～12?cm in diameter by 6?cm in height (excluding tubing); it weighs ～350?g, and is designed to operate at 0.6–1.5?L/min sheath and 0.3?L/min sample flowrates. It features a new sample inlet geometry that is designed to produce a uniform azimuthal particle distribution at the entrance of the classifier, optimized sample/sheath flow streams introduction in the classifier to minimize particle delays, and extension of the electric field interaction volume for ～30% enhanced dynamic range. Based on three-dimensional finite element simulations of flows, electric fields, and particle trajectories, we demonstrate that the Spider DMA transfer functions can be predicted with high fidelity using a parameterized fit based on the Stolzenburg semi-analytical model. Experimental characterization of the instrument response with size-selected particles confirmed close agreement with model prediction; mobility size response is linear over three orders of magnitude in mobility span. Electrical ground shielding of the external surfaces of the DMA has been found to be necessary to avoid particle losses associated with field effects as the high voltage operating limit is approached. The mean deviation between the reference size of polystyrene latex spheres and the Spider DMA measurement is less than 2%, corroborating its high sizing precision and potential for high quality size distribution measurements.

Copyright © 2019 American Association for Aerosol Research     

江泽民马克思主义中国化方法论思想研究

江泽民的马克思主义中国化方法论是中国特色社会主义理论体系的重要组成部分。解放思想、实事求是和与时俱进相统一的方法,继承与发展相结合的方法,整体把握和全面发展的方法,调整结构和整合发展的方法是其主要内容;实践性,历史性,全局性和时代性是其特点。当前对其研究对我们解决中国特色社会主义建设过程中出现的认识和利益问题具有重大意义。     

Characterization of the TSI model 3086 differential mobility analyzer for classifying aerosols down to 1 nm

Measurement systems for particle sizing starting at 1 nm are used to bridge the gap between mass spectrometer measurements and traditional aerosol sizing methods, and thus to enable measurement of the complete size distribution from molecules and clusters to large particles. Such a measurement can be made using a scanning mobility particle sizer equipped with a diethylene glycol growth engine (e.g., TSI Model 3777 Nano Enhancer) along with a condensation particle counter, and a differential mobility analyzer (DMA) appropriate for such small sizes. Previous researchers have used high-resolution DMA (HRDMA) and also the TSI Nano-DMA (Model 3085) in such a scanning mobility particle sizer system. In this study, we evaluate the performance of the recently introduced TSI 1 nm-DMA (Model 3086). The transfer function was characterized using 1–2 nm monomobile molecular ion standards. The same measurements were repeated on a TSI Nano-DMA, with good agreement to previously published values. From the measured transfer function, the resolution of each DMA model was determined as a function of particle size and sheath flow rate. Resolution of the TSI 3086 in the 1–2 nm range was 10–25% higher than the TSI 3085. Measured resolutions of the TSI 3086 were 10–20% lower than theoretically predicted values, whereas those of the Model 3085 were 0–10% lower.

Copyright © 2018 TSI Inc.     

Accuracy of recovered moments for narrow mobility distributions obtained with commonly used inversion algorithms for mobility size spectrometers

Aerosol mobility size spectrometers are commonly used to measure size distributions of submicrometer aerosol particles. Commonly used data inversion algorithms for these instruments assume that the measured mobility distribution is broad relative to the DMA transfer function. This article theoretically examines errors that are incurred for input distributions of any width with an emphasis on those with mobility widths comparable to that of the DMA's transfer function. Our analysis is valid in the limit of slow scan rates, and is applicable to the interpretation of measurements such as those obtained with tandem differential mobility analyzers as well as broader distributions. The analysis leads to expressions that show the relationship between the inverted number concentration, mean size, and standard deviation and true values of those parameters. For narrow distributions (e.g., for a mobility distribution produced by a DMA with a 1:10 aerosol:sheath air flow ratio) under typical operating conditions, number concentrations and mean mobility obtained with inversion algorithms are accurate to within 0.5% and 1.0%, respectively. This corresponds to mean diameter retrieval errors of 1.0% for large particles and 0.5% for small (kinetic regime) particles. The widths (i.e., relative mobility variance) of the inverted distributions, however, significantly exceed the true values.

Copyright © 2018 American Association for Aerosol Research