ΔT化极处理在航磁数据处理中的应用

航磁原始数据是深部和浅部各类地质体的综合反映,为了增强ΔT异常的分辨能力,对航磁原始数据进行了位场转换处理.

人文物体磁测数据化极转换处理效果的评价标准

在与资源勘察和地质调查不同的工程勘察、考古调查等领域,其探测的目标物体常常是炸弹、沉船、古墓葬等由人类制造和建筑的人文物体,由于其生成环境和生成条件与矿床、构造完全不同,因此在对这一类场源进行磁测资料处理时,必然与矿产调查时有所不同。结合模型实验讨论和总结了上述类目标体在化极处理时的差异;讨论了如何根据人文目标体的特点选择参数,并对评价标准进行了总结;另外,还通过勘察工作实例对从模型实验的正反演中得到的认识和评价标准进行了验证。研究得到了比较完美的应用效果,证实和表明了提出的化极处理时参数选择原则和评价标准的可行性和可靠性。

关于磁异常化极的若干体会

一、概述在频率域位场转换中,将磁异常△T或△Z作化极处理,即将磁异常转换为磁性体处于地磁极位置的磁异常(此时地磁场方向垂直向下,当磁性体不存在剩余磁化和不存在迟磁效应时,磁化方向亦垂直向下)是一种常用数据处理方法。一般来说,在垂直磁化时磁性体与磁异常之间的关系会简单一些,将磁异常化至地磁极,如果处理得当,可以取得好的效果。但是由于下面一些众所周知的原因会影响化极的效果,甚至产生严重畸变。首先,由于在频率域位场转换中富氏变换要求被积函数是连续函数,且积分限为(-∞.∞),而磁异常数据总是离散的,测区也总是有限的,容易产生假频而引起高频振荡。

因子处理方法差异对多层递阶预报效果的影响

一、引言天气预报中的多层递阶方法将天气系统看成是随机动态的时变系统,摒弃了固定参数预报模型,受到了气象工作者的关注,并进行了许多有益的探索和尝试,取得了一定效果。但是,由于多层递阶方法应用于气象的历史不长,理论本身也不尽完善,许多问题还有待于解决,加上其物理意义不甚清楚,因而在实际应用时常常不尽人意。

物探方法在黑水县徐古锰矿普查中的应用

介绍了黑水县徐古锰矿的区域地质背景及成矿地质特征,并分析了区域地球物理场和化学场特征。通过采用地面高精度磁法测量得到的磁异常数值,通过化极处理及不同高度的延拓分析,共圈定了11处磁异常体范围,并分析了其对应异常体的长度和延深,为该段矿床勘探提供了明确的地球物理依据,并对部分异常带通过浅深部工程进行了异常查证,找矿效果显著。

Influence of thermomechanical treatments on localized corrosion susceptibility and propagation mechanism of AA2099 Al-Li alloy

In order to manifest the influence of specific microstructural component on the development of severe localized corrosion in an AA2099 aluminum-lithium alloy, the corrosion behavior of the alloy subjected to solution heat treatment, cold working and artificial ageing was investigated. Immersion testing and potentiodynamic polarization were employed to introduce localized corrosion; scanning electron microscopy and transmission electron microscopy were used to characterize the alloy microstructure and corrosion morphology. It was found that the susceptibility of the alloy to severe localized corrosion was sensitive to thermomechanical treatments. Additionally, the state of alloying elements influenced the mechanism of localized corrosion propagation. Specifically, the alloy in T8 conditions showed higher susceptibility to severe localized corrosion than that in other conditions. During potentiodynamic polarization, the alloy in solution heat-treated and T3 conditions displayed crystallographic corrosion morphology while the alloy in T6 and T8 conditions exhibited selective attack of grain interiors and grain boundaries in local regions.

普惠金融发展水平的测度与比较研究

提高普惠金融发展水平是深化金融改革的重要内容。本文从普惠金融的使用性、可得性和质量性三个层次出发,采取极值化处理法与变异系数法相结合的方法,选取20个评价指标,构建分层次普惠金融发展水平指标评价体系,并对各省区普惠金融发展水平进行测度评价。同时,根据普惠金融指标得分分析各区域提高普惠金融发展水平的方向。

高精度磁测在原平市孙家庄铁矿勘查中的应用

孙家庄铁矿床是隐伏于第四系之下的沉积变质型铁矿床,通过高精度的磁法扫面和剖面测量,获取直接的磁异常数据,采用化极处理、向上延拓分析、剖面解释等方法,确定了异常体的空间位置、产状及规模大小,为矿床勘查提供了较为明确的地球物理依据。

Anodizing parameters for superheated slurry cast 7075 aluminum alloys

The anodizing parameters of voltage, current density, temperature, and electrolyte choice were assessed to find an appropriate combination for the superheated slurry cast 7075 Al alloy substrate.The alloy was anodized in sulfuric acid electrolyte or alternatively in sulfuric acid mixed with boric acid or citric acid. The voltages applied were in the range of 15-30 V. Anodizing current densities tested were 2 and 3 A/dm^2,while temperatures tested were 5 and 15 ℃. Thickness, surface morphology, hardness,and corrosion resistance of the oxide film were then evaluated.It was found that 25 V,2 A/dm^2 and 5 ℃ were suitable for this alloy when anodized in sulfuric acid. The oxide film was smooth with uniform thickness, low porosity, high hardness,and had the highest corrosion resistance at these parameters. However, discontinuous oxide films were observed from samples anodized at higher temperature of 15 ℃.Alternative electrolytes considered were sulfuric acid mixed with boric acid or citric acid. The results showed that electrolytes with boric acid or citric acid increased thickness, hardness, corrosion resistance and quality of the oxide films.However, these oxide films were inferior to those obtained with sulfuric acid electrolyte at lower temperature(25 V, 2 A/dm^2 and5 ℃).

Effect of Anodization Parameters on Morphologies of TiO2 Nanotube Arrays and Their Surface Properties

This work presents the potentiostatic anodization study of titania nanotube array films fabricated in fluoride-based organic electrolytes including DEG （diethylene glycol） and EG （ethylene glycol）. The work focuses on the effect of important anodization parameters such as applied voltage, anodization time, and electrolyte type on nanotube morphologies and corresponding surface properties. Depending upon unique nanotube formation structures obtained from each anodizing electrolyte, wettability of the nanotube array layer has been determined by means of the contact angle measurement. The EG nanotube array films with close-packing cell orientation are found to show hydrophilic behavior. While the well separated DEG nanotube array films are found to exhibit hydrophobic behavior, with the characteristics of more discrete, wider cell separation obtained through manipulating the electrolyte conditions and the fabrication techniques offering considerable prospects for developing the superhydrophobic sample surface. Such formation structures observed for the DEG fabricated nanotube is believed to play a prominent role in determining the surface wettability of the anodized nanotube array film. The achieved result in this work is anticipated to pave the way to other relevant applications, where interfacial properties are critically concerned.

高精度磁测在辽宁省新宾县榆树铁矿勘查中的应用

通过对辽宁省新宾县榆树铁矿的勘查工作,获取了直接的磁异常数据,通过化极和不同高度的延拓处理,分析了其对应异常体的相对深度,为合理解释深部磁铁矿体走向、产状和埋深提供了较为明确的地球物理依据。

Microbial Electrolysis Cells for Hydrogen Production

Microbial electrolysis cells(MECs)present an attractive route for energy-saving hydrogen(H2)production along with treatment of various wastewaters,which can convert organic matter into H2 with the assistance of microbial electrocatalysis.However,the development of such renewable technologies for H2 production still faces considerable challenges regarding how to enhance the H2 production rate and to lower the energy and the system cost.In this review,we will focus on the recent research progress of MEC for H2 production.First,we present a brief introduction of MEC technology and the operating mechanism for H2 production.Then,the electrode materials including some typical electrocatalysts for hydrogen production are summarized and discussed.We also highlight how various substrates used in MEC affect the associated performance of hydrogen generation.Finally we presents several key scientific challenges and our perspectives on how to enhance the electrochemical performance.

Mild oxidation treatment of graphite anode for Li-ion batteries

The graphite was modified by mild oxidation, and the effects of modification temperature and soaking time on the characteristics of graphite were investigated. The structure and characteristics of the graphite were determined by X-ray diffraction, scanning electron microscopy, BET surface area, particle size analysis and electrochemical measurements. The results show that the modified graphite has a better-developed crystallite structure, larger average particle diameter, smaller surface area, and better electrochemical characteristics than the untrented graphite. The sample mild-oxidized at 600℃ for 3h has the best electrochemical performances with a reversible capacity of 304.5mA·h/g, a irreversible capacity of 66.4mA·h/g, and a initial coulombic efficiency of 82.1%. The charge/discharge properties and a cycling stability of the prototype lithium ion batteries with modified graphite as anodes are improved. Its capacity retention ratio at the 200th cycle is enhanced from 66.75% to 90.15%.

Microstructure and abrasive wear behaviour of anodizing composite films containing Si C nanoparticles on Ti6Al4V alloy

Anodized composite films containing Si C nanoparticles were synthesized on Ti6Al4 V alloy by anodic oxidation procedure in C4O6H4Na2 electrolyte. Scanning electron microscopy(SEM), energy dispersive spectroscopy(EDS) and X-ray photoelectron spectroscopy(XPS) were employed to characterize the morphology and composition of the films fabricated in the electrolytes with and without addition of Si C nanoparticles. Results show that Si C particles can be successfully incorporated into the oxide film during the anodizing process and preferentially concentrate within internal cavities and micro-cracks. The ball-on-disk sliding tests indicate that Si C-containing oxide films register much lower wear rate than the oxide films without Si C under dry sliding condition. Si C particles are likely to melt and then are oxidized by frictional heat during sliding tests. Potentiodynamic polarization behavior reveals that the anodized alloy with Si C nanoparticles results in a reduction in passive current density to about 1.54×10-8 A/cm2, which is more than two times lower than that of the Ti O2 film(3.73×10-8 A/cm2). The synthesized composite film has good anti-wear and anti-corrosion properties and the growth mechanism of nanocomposite film is also discussed.

Effects of sodium tungstate on properties of micro-arc coatings on magnesium alloys

Anodic coatings were prepared by micro-arc oxidation on AZ91HP magnesium alloys in a base solution containing 10 g/L NaOH and 12 g/L phytic acid with addition of 0-8 g/L sodium tungstate.The effects of sodium tungstate on the coating thickness, mass gain,surface morphology and corrosion resistance were studied by eddy current instrument,electronic scales,scanning electron microscope and immersion tester.With the addition of sodium tungstate,the electrolytic conductivity increases and the final voltage decreases.The sodium tungstate has a minor effect on the coating thickness,but lightens the coating color.With increasing sodium tungstate concentration,the size of micropores on the coatings is enlarged and the corrosion resistance of the anodized samples decreases.

Solar Collectors of Buildings Facade Based on Aluminum Heat Pipes with Colored Coating

A variety of liquid thermal solar collectors designs used for water heating have been developed by the previous researchers. But the majority of them do not meet the requirements on small weight, easy assembling and installing, versatility, scalability and adaptability of the design, which are particularly important when they are facade integrated. In order to avoid the above mentioned drawbacks of the liquid thermal collectors, the authors propose to apply to them extruded aluminum alloy made heat pipes of originally designed cross-sectional profile with wide fins and longitudinal grooves. Such solar collectors could be a good solution for building facade and roof integration, because they are assembled of several standard and independent, hermetically sealed and light-weight modules, easy mounted and ＂dry＂ connected to the main pipeline. At that, their thermal performances are not worse than of the other known ones made of heavier and more expensive copper with higher thermal conductance, or having entire rigid designs. Some variants of the developed solar collectors shaping of the assembled modules for building facade or roof integration are proposed. Variously colored coatings to the absorbers are developed and made of carbon-siliceous nano-composites by means of sol-gel method. Their optical performances were compared with ＂anodized black＂. It is stated that colored coatings have a good prospect in thermal SCs （solar collectors） adaptation to building facades decoration, but the works on study and upgrade of their performances should be continued.

Green Synthesis of RuO2 Electrode for Electrochemical Water Treatment

Nowadays, the electrochemical water treatments are very important methods used for the removal of organic and inorganic impurities from fresh, drinking water and wastewater. The method consists of carrying out the oxidation reaction at the anode where pollutants are transferred into non-toxic substances, by decomposing into simpler compounds or transferring into oxidation form. RuO2-based Dimensional Stable Anode （DSA） is a technologically good and important electrode for water treatment because of its unique characteristics such as high thermal and chemical stability, low resistivity and low overpotential. This paper reviews the methods for fabricating RuO2-based electrodes that can be used in electrochemical water treatment. Depending on the different fabrication routes, RuO2 electrodes will possess the different electro-catalytic property and stability.

AN UNSUPERVISED CLASSIFICATION FOR FULLY POLARIMETRIC SAR DATA USING SPAN/H/α IHSL TRANSFORM AND THE FCM ALGORITHM

In this paper, the IHSL transform and the Fuzzy C-Means (FCM) segmentation algorithm are combined together to perform the unsupervised classification for fully polarimetric Synthetic Ap-erture Rader (SAR) data. We apply the IHSL colour transform to H/α/SPANspace to obtain a new space (RGB colour space) which has a uniform distinguishability among inner parameters and contains the whole polarimetric information in H/α/SPAN.Then the FCM algorithm is applied to this RGB space to finish the classification procedure. The main advantages of this method are that the parameters in the color space have similar interclass distinguishability, thus it can achieve a high performance in the pixel based segmentation algorithm, and since we can treat the parameters in the same way, the segmentation procedure can be simplified. The experiments show that it can provide an improved classification result compared with the method which uses the H/α/SPANspace di-rectly during the segmentation procedure.

Vertically oriented TiO_2 nanotube arrays with different anodization times for enhanced boiling heat transfer

Pool boiling of saturated water on a plain Ti surface and surfaces covered with vertically-oriented TiO2 nanotube arrays(NTAs) has been studied.The technique of potentiostatic anodization using non-aqueous electrolytes was adopted to fabricate three types of TiO2 NTAs distinguished by their anodization time.Compared to the bare Ti surface,the incipient boiling wall superheat on the TiO2 NTAs was decreased by 11 K.Both the critical heat flux and heat transfer coefficient of pool boiling on the TiO2 NTAs were higher than those from boiling on a bare Ti surface.The measured maximum critical heat flux and heat transfer coefficient values were 186.7 W/cm2 and 6.22 W/cm2K,respectively.Different performances for the enhancement of heat transfer by the three types of TiO2 NTAs were attributed to the different degrees of deformation in the nanostructure during boiling.Long-term performance of the nanomaterial-coated surfaces for enhanced pool boiling showed degradation of the TiO2 NTAs prepared with an anodization time of 3 hours.

Synthesis and Characterization of Niobium-doped TiO_2 Nanotube Arrays by Anodization of Ti-20Nb Alloys

Well crystallized niobium-doped TiO; nanotube arrays （TiNbO-NT） were successfully synthesized via the anodization of titanium/niobium alloy sheets, followed with a heat treatment at 550 ℃ for 2 h. Morphology analysis results demonstrated that both the titanium/niobium alloy microstructure and the dissolution strength of electrolyte played major roles in the formation of nanotube structure. A single-phase microstructure was more favorable to the formation of uniform nanotube arrays, while modulating the dissolution strength of electrolyte was required to obtain nanotube arrays from the alloys with multi-phase microstructures. X-ray diffraction （XRD） and X-ray photoelectron （XPS） analysis results clearly demonstrated that niobium dopants （Nb^5＋） were successfully doped into TiO2 anatase lattice by substituting Ti^4＋ in this approach.