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91.
赵庆令  李清彩 《岩矿测试》2013,32(6):883-886
锆钛砂矿是一种极难消解的矿物,除氢氟酸外,几乎不溶于所有的酸,由于矿物中铪、钛、锆含量高,而铪、钛、锆又易水解形成难溶的偏铪酸、偏钛酸、偏锆酸析出,样品前处理给定量分析带来很大困难。传统的化学法繁琐费时,且只能进行锆(铪)合量的分析。本文建立了电感耦合等离子体发射光谱法(ICP-AES)测定锆钛砂矿样品中铪、钛、锆的方法。通过筛选四种溶矿方法,确定在刚玉坩埚中用过氧化钠于700℃时熔融样品,硝酸-EDTA浸取盐分前处理矿物,利用EDTA的强络合性质可使铪、钛、锆形成稳定的可溶络合物,制备出有代表性的样品溶液;在ICP-AES分析中,采用Re作为内标和大的高频功率消除了基体效应的影响。方法的精密度(RSD,n=11)低于1.3%,Hf、Ti、Zr的检出限分别为0.97 μg/g、0.86 μg/g、0.33 μg/g。实际样品的测定值与化学分析方法和X射线荧光光谱法的测定结果基本吻合。。本方法采用刚玉坩埚熔矿,提高了样品处理数量,降低了分析成本,适用于难熔锆钛砂矿样品的快速定量分析。  相似文献   
92.
This paper presents a set of energy and resource intensive scenarios based on the concept of Shared Socio-Economic Pathways (SSPs). The scenario family is characterized by rapid and fossil-fueled development with high socio-economic challenges to mitigation and low socio-economic challenges to adaptation (SSP5). A special focus is placed on the SSP5 marker scenario developed by the REMIND-MAgPIE integrated assessment modeling framework. The SSP5 baseline scenarios exhibit very high levels of fossil fuel use, up to a doubling of global food demand, and up to a tripling of energy demand and greenhouse gas emissions over the course of the century, marking the upper end of the scenario literature in several dimensions. These scenarios are currently the only SSP scenarios that result in a radiative forcing pathway as high as the highest Representative Concentration Pathway (RCP8.5). This paper further investigates the direct impact of mitigation policies on the SSP5 energy, land and emissions dynamics confirming high socio-economic challenges to mitigation in SSP5. Nonetheless, mitigation policies reaching climate forcing levels as low as in the lowest Representative Concentration Pathway (RCP2.6) are accessible in SSP5. The SSP5 scenarios presented in this paper aim to provide useful reference points for future climate change, climate impact, adaption and mitigation analysis, and broader questions of sustainable development.  相似文献   
93.
林业作为实施“基于自然的解决方案(NbS)”的重要领域和路径选择,在落实NbS行动中越来越受到各国政府和专家学者的广泛支持。文中在回顾国内外NbS相关资料的基础上,总结分析了林业领域NbS的内涵和路径、国际和国内相关政策及已采取的措施,重点分析了林业NbS路径的减排潜力、成本与效益。从全球范围看,造林和再造林路径具有较高的技术减排潜力,而减少毁林和森林经营管理是相对更具有成本效益的增汇减排路径。中国对林业NbS的实践及科学研究等尚显不足,但已有的重大林业生态工程已经产生了显著的减排效益和经济效益。未来需要在林业NbS相关标准与计量体系建设、减排技术与经济潜力研究、激励与保障机制等政策研究,以及增强公众意识等方面进一步深化和发展。  相似文献   
94.
过渡金属Cu、Co、Ni、Zn、Pb等及贵金属元素(铂族元素和Au、Ag)高度富集在硫化物中,尤其是富集在岩浆硫化物中,常形成具有工业开采价值的矿产,因而硫化物矿物具有重大的经济价值。而硫化物矿种类多,不同类型硫化物矿中Ag、Cu、Pb、Zn含量高低不同,有些被强酸分解不完全,产生沉淀,导致检测结果波动性较大、精密度偏低。本文针对含黄铁矿、铅和铜分别以方铅矿和黄铜矿形式存在的较难溶的硫化物矿,在矿样中先加盐酸加热除硫后,再用硝酸-氢氟酸-高氯酸三种强酸分解,以新配制的王水提取,使该类样品获得了理想的分解效果,特别是对银、铅含量较高的样品分解效果改善较显著。试液用火焰原子吸收光谱和电感耦合等离子体发射光谱都能准确测定Ag、Cu、Pb、Zn,两种方法的相对误差在±2.32%以内,测定值基本一致,相对标准偏差(RSD,n=12)均小于3.5%,四个元素的检出限均低于0.0090!g/m L,低于文献检出限。  相似文献   
95.
Dust events occurred frequently in Beijing in recent years. In this work, 120 aerosol samples werecollected in two typical dust events (21-22 March and 15 May) and a non-dust period in Beijing fromMarch to May 2001. Samples were analyzed for major elemental components by the Proton Induced X-ray Emission (PIXE) method. Results show that the enrichment factors of crustal elements such as Mg,A1, and Ti had little differences between the dust period and the non-dust period in Beijing, while theenrichment factors of other elements that have a relation to anthropogenic emissions were very low duringthe dust period. The results derived by using multivariate factor analysis from the observation data showthat the sources such as soil dust, industry, and fuel combustion were among the major contributors tothe particles in Beijing.  相似文献   
96.
徐国栋  金斌  葛建华  董俊  程江 《岩矿测试》2016,35(2):134-137
目前采用酸溶分解试样,以硫脲或磷酸氢二铵为基体改进剂,应用石墨炉原子吸收光谱法(GFAAS)可以直接测定各类地质样品中的痕量银;但应用于测定碳酸盐岩中的痕量银时,基体元素钙镁会产生干扰,同时影响石墨管的使用寿命。本文采用盐酸-硝酸-氢氟酸-高氯酸四酸溶样,硝酸提取,以草酸铵(45.5 g/L)作基体改进剂,试液中的钙镁与草酸铵快速反应生成白色沉淀物而分离,并形成了具有挥发性的铵盐介质环境,可显著提高石墨炉的灰化温度进一步除去铵盐介质,从而消除了基体元素的各种影响。本方法操作简单,经国家标准物质验证,其测定值与标准值的相对偏差均小于10%,检出限为0.010μg/g,精密度(RSD,n=12)小于1.0%。本方法不仅分离了干扰基体,而且比前人采用的一米光栅发射光谱法的检出限(0.04μg/g)更低。  相似文献   
97.
Biodiesel, which is manufactured from vegetables oils, animal fats, or algae can be an excellent alternative fuel to petroleum diesel due to its superior fuel properties and lower pollutant emissions. In contrast, fishing-boat fuel generally has much poorer fuel properties and a high sulfur content that can reach several hundred times that of the premium diesel used in land-based vehicles. Pollutant emissions from fishing boats are known to be a significant source of air pollution in the global environment. This study examines the use of biodiesel to replace fishing-boat fuel A to reduce pollutant emissions from fishing boats. The incremental cost, reduction in emissions, and cost-benefit corresponding to various weight proportions of biodiesel to replace fishing-boat fuel A are evaluated. The results show that the annual consumption of fishing-boat fuel A by Taiwanese fishing boats amounts to 649,201 kiloliters (kl) and total emissions from burning the fuel is 958.93 tons per year. If all fishing-boat fuel A were replaced with biodiesel, then pollutant emissions would be decreased by 421.94 tons, or 44.0%. However, this would also result in a USD 144.45 million or 25.85% increase in fuel cost. This study also finds that a replacing 20 wt% of fishing-boat fuel A with biodiesel has the highest cost-benefit ratio, which implies a larger reduction in emissions with a lower fuel cost increase, and is the most suitable option for fishing boats in Taiwan.  相似文献   
98.
A new airborne remote sensing approach to estimate an upper limit of the direct sea-air methane emission flux was applied over the 22/4b blowout site located at N57.92°, E1.63° in the North Sea. Passive remote sensing data using sunglint/sunglitter geometry were collected during instrumental tests with the Methane Airborne MAPper – MAMAP – instrument installed aboard the Alfred Wegener Institute (AWI) Polar-5 aircraft on 3. June 2011. MAMAP is a passive short wave infrared (SWIR) remote sensing spectrometer for airborne measurements and retrieval of the atmospheric column-averaged dry air mole fractions of methane (XCH4) and carbon dioxide (XCO2). In addition to MAMAP a fast CH4 in-situ analyzer (Los-Gatos Research Inc. RMT-200), two 5-hole turbulence probes and the Polar-5 basic sensor suite comprising different temperature, pressure, humidity and camera sensors were installed aboard the aircraft. The collected MAMAP remote sensing data acquired in the vicinity of the 22/4b blowout site showed no detectable increase in the derived XCH4 (with respect to the atmospheric background). Based on the absence of a detectable XCH4 column increase, an approximate top-down upper-limit for the direct atmospheric 22/4b blowout CH4 emissions from the main bubble plume of less than 10 ktCH4/yr has been derived. The constraint has been determined by comparing XCH4 information derived by the remote sensing measurements with results obtained from a Gaussian plume forward model simulation taking into account the actual flight track, the instrument sensitivity and measurement geometry, as well as the prevailing atmospheric conditions.  相似文献   
99.
Kye Hwa Yoo   《New Astronomy》2010,15(2):215-226
The symbiotic variable star CH Cygni went on the deepest minimum phase in December 2006. A high-resolution spectrum of CH Cygni obtained at the Bohyunsan Optical Astronomy Observatory (BOAO) on November 2, 2006, is reported. The spectrum of CH Cygni obtained at the BOAO was calibrated on a scale of an absolute-flux density. Emission lines of H I, [O III], [N II], and [S II] were strong, with several components, and Ca II, H, and K lines had P-Cygni profiles. Removal of the spectrum of the underlying M-type star from the CH Cygni spectrum was completed to obtain the true emission profiles. The radial velocities of all emission and absorption lines were measured. Some of the observed lines were also deconvoluted using multi-Gaussian functions to find the relationship between line shapes and the corresponding sources of these lines. The results obtained are discussed in terms of an accretion disk around the hot star, and in non-spherically extended nebular regions.  相似文献   
100.
The low frequency array (LOFAR) radiotelescope will be a powerful instrument for answering fundamental, unresolved scientific questions concerning solar system radio phenomena and related emissions from nearby stellar systems. This paper reviews the phenomena, emission mechanisms, open scientific questions, and LOFAR's capabilities. LOFAR will detect metric solar radio bursts in the corona and interplanetary medium, out to distances of order 10 solar radii, as well as Jovian radio emissions. Arguments are given that LOFAR may be sufficiently sensitive to detect stellar analoges of solar type II and III bursts, and may detect cyclotron-maser emissions from extra-solar planets. LOFAR may also aid space weather research, by passively detecting coronal mass ejections (CMEs) via scintillation and Faraday rotation effects, or by detecting radar signals bounced off CMEs and coronal density structures if a suitable solar radar is developed.  相似文献   
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