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51.
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
52.
Degraded fuel oils are generally used in marine power plants for economic purposes, so as to reduce operating expenses. These marine fuel oils commonly contain various oxides or sulfide compounds of metallic elements in the fuel ash, and affect the combustion and emission characteristics of marine power plants to different extents. Moreover, marine power plants are more often operated in a highly humid environment. As a result the emission and burning process may also be altered by the various humidity level of the inlet air. The effects of potassium sulfide in marine diesel on the combustion and emission characteristics of marine furnaces under varying levels of relative humidity of inlet air were experimentally investigated in this study. A cylindrical industrial furnace made of AISI 316 stainless steel, and an automatic oil-fired burner were used for the emission characteristics measurements and observation. A mechanically homogenizing machine was used to stir potassium sulfide (K2SO4) powder and marine diesel with a preset K2SO4 concentration. The relative humidity of the inlet air and temperature were adjusted to their assigned values by a large-size air conditioner before being pumped into the burner. The marine diesel oil mixture was atomized by the inlet air consequently ignited by an electrode and then burned within the horizontal furnace. There were eight rectangular slots cut in the upper portion of the furnace wall so that the probes of a gas analyzer and a thermocouple could be inserted into radial positions in the cylindrical furnace. The concentrations of gas emission and burning gas temperature and the combustion efficiency were analyzed. The experimental results show that the burning gas temperature, carbon dioxide emission and combustion efficiency decreased when the concentrations of excess air and oxygen emission increased with the addition of potassium sulfide in the marine diesel fuel. This is primarily attributed to the fact that the sulfide of an alkali compound such as K2SO4 may suppress the oxidation reaction process, leading to inferior combustion characteristics. 相似文献
53.
顺序扫描 ICP-AES法测定高纯石墨灰分中14种杂质金属元素的方法研究 总被引:1,自引:0,他引:1
本文研究了快速测定石墨灰分中14种杂质元素Al,Ca,Cd,Co,Cr,Cu,Fe,Mg,Mn,Mo,Ni,Ti,V,Zn的分析方法,以满足提纯石墨研究工作对快速了解石墨提纯效果的要求.依据测定样品中各元素的含量情况,实验选择14种元素的分析线.运用ICP-AES谱线轮廓图功能,消除常量元素产生的基体背景干扰.运用干扰系数法进行测定结果校正,并对ICP-AES测定灰分中14种元素的检出线、精密度、准确度进行了测定.结果显示,本方法分析石墨灰分中杂质元素能够满足提纯石墨研究工作的要求. 相似文献
54.
Marine power plants are frequently operated under varying atmospheric air temperature and humidity conditions. The effects of inlet air temperatures and humidity of marine furnaces such as incinerators and boilers thus attract much research interest. An industrial furnace incorporated with an automatic burner was employed to experimentally investigate the influences of the inlet air temperature and humidity on the emission characteristics. The inlet air humidity and temperature were adjusted using an air-conditioning machine to preset values before being admitted into the burner. ASTM No. 2D diesel oil was atomized, mixed with the inlet air and burned inside the industrial furnace. Eight small rectangular slots were cut on the upper side of the furnace to allow gas analyzer and thermocouple probes to be inserted into the furnace center to measure the axial variations in the gas temperature, burning efficiency and burning gas compositions such as NOx, SO2, CO. The experimental results show that the O2 and NOx emission concentrations decreased while the CO2 emission concentration and burning efficiency increased with either increasing inlet air humidity or temperature. 相似文献
55.
配额拍卖机制在碳市场中具有重要作用。文中在综述配额拍卖机制研究进展的基础上,重点回顾拍卖机制在欧盟、美国加州和澳大利亚等具有代表性的国际碳市场中的应用情况,结合国内试点碳市场的运行情况,分析不同地区碳市场中拍卖机制的效果。研究认为,国际碳市场拍卖机制设计较为完善,在实际应用中效果良好,起到了增强市场流动性的作用,国内各试点碳市场拍卖机制仍处于探索阶段。文中从拍卖机制的要素设计、平台建设、所得资金管理等方面对全国统一碳市场配额拍卖机制设计提出建议,为全国碳市场中拍卖机制的建设提供参考。 相似文献
56.
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
57.
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
58.
59.
The concentrations of particulate Polycyclic aromatic hydrocarbons (PAHs) were measured at Gosan, a background site in Korea for 1 year between November 2001 and November 2002. The total concentrations of 14 PAH compounds at Gosan were between 0.52 and 14.76 ng m− 3 and about 3–15 times higher than those at other rural or remote sites in the world. Seasonal trend was observed for particulate PAHs concentrations at Gosan with higher levels during heating season due to increased fossil fuel usage and the movement of air parcels from Asian continent. Principal component factor analysis (PCF) for PAHs showed three factors; combination of coal combustion and vehicular emission, natural gas combustion, and unidentified one. However, PCF for the combined data of PAHs, inorganic ions, and elements revealed that the unidentified factor consists of crustal species, sea salts, and four PAH compounds. Thus, this factor is thought to be transport of crustal species with organics from combustion sources. The major variables which determine the sources of PAHs are the heating season and the movement of air parcels from Asian continent. 相似文献
60.
黑碳气溶胶研究进展Ⅰ:排放、清除和浓度 总被引:28,自引:0,他引:28
黑碳气溶胶是近几年非常活跃的一个研究课题,因为黑碳气溶胶吸收太阳和地球大气的辐射,对全球气候变暖有重要的影响。中国黑碳气溶胶的排放和浓度比同纬度的高,在全球气候变暖的大背景下,中国黑碳气溶胶一直受到国外的关注。综述了国内外黑碳气溶胶研究的最新进展,受篇幅的限制,文章分两篇,第一篇是黑碳气溶胶的排放、清除和浓度,第二篇是黑碳气溶胶的气候效应和拓展的研究领域。从黑碳排放的估算和大气浓度的测量方法进行描述,列出有关的测量结果,对黑碳气溶胶的排放和大气浓度进行国内外的初步比较分析。还对黑碳气溶胶排放和浓度测量误差进行了讨论,并对今后黑碳气溶胶研究提出了几点建议。 相似文献