985 resultados para Ni-Cr-Mo-Ti


Relevância:

100.00% 100.00%

Publicador:

Resumo:

采用等温凝固方法研究了单晶镍基合金的凝固区间,利用DSC测试了合金的凝固曲线.结果表明:实验合金的液相线温度约为1380℃,固相线温度约为1310℃.合金的凝固顺序为: Lγ,L MC;γγ′;Lγ+MC.单晶合金的铸态组织中,W偏析于枝晶干, Ti,Cr,Mo和Ta偏析于枝晶间,偏析程度为: Mo>Ti>Cr>Ta, Al和Co几乎不发生偏析.1314℃1382℃1361℃1325℃

Relevância:

100.00% 100.00%

Publicador:

Resumo:

Effect of La-Mg-based alloy (AB(5)) addition on Structure and electrochemical characteristics of Ti0.10Zr0.15V0.35Cr0.10Ni0.30 hydrogen storage alloy has been investigated systematically. XRD shows that the matrix phase structure is not changed after adding AB(5) alloy, however, the amount of the secondary phase increases with increasing AB(5) alloy content. The electrochemical measurements show that the plateau pressure Ti0.10Zr0.15V0.35Cr0.10Ni0.30 + x% La0.85Mg0.25Ni4.5Co0.35Al0.15 (X = 0, 1, 5, 10, 20) hydrogen storage alloys increase with increasing x, and the width of the pressure plateau first increases when x increases from 0 to 5 and then decreases as x increases further, and the maximum discharge capacity changes in the same trend.

Relevância:

100.00% 100.00%

Publicador:

Resumo:

测定了胜利油田惠民凹陷14件辉绿岩的过渡元素(Sc、Ti、Cr、Mn、Fe、Ni、Cu和Zn)含量。结果显示岩石中Cr和Ni含量具有很宽的范围(分别为76.9×10^-6~1049×10^-6和56.7×10^-6~495×10^-6),样品商745.2出现异常高的Cr和Ni含量,分别为8718×10^-6和4530×10^-6;Cu和Zn含量高且变化范围大,半数以上样品的Cu和Zn含量分别大于1000×10^-6(1082×10^-6~8111×10^-6)和500×10^-6(634×10^-6~2198×10^-6)。分析认为,本区辉绿岩Cr和Ni含量变化范围宽与岩浆结晶分异作用有关,具异常高Cr和Ni含量样品可能为岩浆演化相对后期,有大量铬铁矿结晶的产物;岩石富集Cu和Zn可能与岩浆上升过程中遭受地壳物质混染作用有关.

Relevância:

100.00% 100.00%

Publicador:

Resumo:

本论文按照统一的采样和统一的分析测试方法对全国煤中22种环境敏感微量元素及全硫含量进行了系统的研究。通过统计学的方法不仅给出了中国煤炭部分环境敏感微量元素的分布范围、算术均值、标准差、几何均值、几何偏差,中位数,而且首次给出了95%置信度下算术均值、几何均值以及元素含量分布的置信区间等,并与前人大量样品的统计结果进行比较。还通过统计分析了部分环境敏感微量元素在我国煤中的主要赋存状态,以及选煤对这部分微量元素的脱除机理和脱除效果等,得到以下几点认识: 1. 通过与前人大量样品统计所得到的结果进行比较,进一步证明了论文中使用的这批样品是中国煤炭平均化学成分的良好代表。本次所分析的23种元素中,As、Be、Co、Cr、Cu、Hg、Pb、Se、Th、Tl、U、F、S等13元素与前人数10年研究的统计结果在分布范围、均值含量等上非常一致,但本次的结果更为可信,更接近中国煤炭平均化学成分的真实状况。此外,本次对这B、Sn这2种元素的分析数据也是目前反映我国煤中分布最具有代表性的数据。 2. 根据样品的无偏性,对平均值的置信区间进行计算。首次给出了全国煤中各元素在95%置信度下的算术均值的置信区间、几何均值的置信区间以及元素含量分布的置信区间等。可以为后人研究各元素在绝大多数煤中的含量及均值情况时作为参考。同时统计分析表明,按照95%置信度计算,16元素的真实平均值在我们所得到的平均值±11%范围之内,最大偏差为硒,在±20%之间。 3. 平均值作为最常用的统计量之一,中国煤中不同元素的不同均值之间有一定的差异,反映了元素在煤中不同的分布状态。论文中通过对23种元素在全国煤中的5种不同的均值比较,一般元素的产量加权均值与总体样品均值之间都比较接近;绝大多数元素的储量加权均值比较低,这与西北、华北地区未开采利用的煤炭资源量大,煤质好有关。 4. 通过与Swaine(1990)给出世界煤中元素的分布范围进行比较,22种环境敏感微量元素在我国煤中的分布处于世界煤的有限范围之内。其中,Cr、Cu、Mn、Mo、Se、Sn、Th、Tl、U、V、F等微量元素在我国煤中的分布与世界煤比较接近,而As、B、Ba、Be、Cd、Co、Cl、Hg、Ni、Pb、Sb等微量元素在我国煤中较世界煤低很多。 5. 与世界主要煤炭资源大国和Swaine(1990)给出的世界煤元素均值含量的比较显示,大部分环境敏感微量元素在我国煤中的均值含量与世界主要煤炭资源大国煤中的均值含量也比较接近。其中,我国煤中B、Co、Cu、Hg、Pb、U等6种元素含量均值与美国煤比较接近,As、Cd、Sb、Tl等4种元素含量均值与澳大利亚煤比较接近,Ba、Cr、Mo、Ni、V等4种元素含量均值与前苏联煤比较接近,Be、Mn、Se、Th、F等5种元素含量均值与世界煤比较接近。 6. 随着煤炭变质程度的增高,各元素均值含量没有表现出明显规律性的增高或降低。但22种环境敏感微量元素在褐煤、弱粘煤、不粘煤、气煤等较低变质程度煤中的含量整体水平不高,绝大多数微量元素主要在中高变质程度煤中较为更为富集。不同成煤时期以及不同聚煤区煤中各种环境敏感微量元素不同的富集程度,从总体上反应了绝大部分环境敏感微量元素在华南煤中更为富集,而占全国储量3/4的华北和西北煤中的总体水平相对较低。 7. 通过对环境敏感微量元素与灰分及主要灰成分之间的关系进行分析,初步了解了它们在煤中的主要赋存状态。煤中绝大部分环境敏感微量元素还是具有非常明显的无机亲和性,在煤中主要以矿物无机形态存在。主要与粘土矿物、黄铁矿及硫化物相结合,而与碳酸盐矿物关系不大。 8. 脱除率的分析显示,15种元素的脱除率与灰分的脱除率之间具有显著的正相关性,说明煤中绝大部分环境敏感微量元素主要以无机形态存在,因此提高原煤入洗率,降低原煤灰分的同时也可以在很大程度上降低环境敏感微量元素的燃煤排放。 9. 部分环境敏感元素的脱除率受到其在煤中的赋存状态、矿物形态、煤级以及选煤厂洗选工艺等诸多因素的影响,在不同样品中脱除率的差异较大。某些样品中微量元素的脱除率较高,最高脱除率可达到70%以上。从平均脱除率来看,灰分、硫分及绝大多数环境敏感微量元素处于30%-70%之间,只有少数几个元素不到20%。

Relevância:

100.00% 100.00%

Publicador:

Resumo:

Mangroves are considered to play a significant role in global carbon cycling. Themangrove forests would fix CO2 by photosynthesis into mangrove lumber and thus decrease the possibility of a catastrophic series of events - global warming by atmospheric CO2, melting of the polar ice caps, and inundation of the great coastal cities of the world. The leaf litter and roots are the main contributors to mangrove sediments, though algal production and allochthonous detritus can also be trapped (Kristensen et al, 2008) by mangroves due to their high organic matter content and reducing nature are excellent metal retainers. Environmental pollution due to metals is of major concern. This is due to the basic fact that metals are not biodegradable or perishable the way most organic pollutants are. While most organic toxicants can be destroyed by combustion and converted into compounds such as C0, C02, SOX, NOX, metals can't be destroyed. At the most the valance and physical form of metals may change. Concentration of metals present naturally in air, water and soil is very low. Metals released into the environment through anthropogenic activities such as burning of fossils fuels, discharge of industrial effluents, mining, dumping of sewage etc leads to the development of higher than tolerable or toxic levels of metals in the environment leading to metal pollution. Of course, a large number of heavy metals such as Fe, Mn, Cu, Ni, Zn, Co, Cr, Mo, and V are essential to plants and animals and deficiency of these metals may lead to diseases, but at higher levels, it would lead to metal toxicity. Almost all industrial processes and urban activities involve release of at least trace quantities of half a dozen metals in different forms. Heavy metal pollution in the environment can remain dormant for a long time and surface with a vengeance. Once an area gets toxified with metals, it is almost impossible to detoxify it. The symptoms of metal toxicity are often quite similar to the symptoms of other common diseases such as respiratory problems, digestive disorders, skin diseases, hypertension, diabetes, jaundice etc making it all the more difficult to diagnose metal poisoning. For example the Minamata disease caused by mercury pollution in addition to affecting the nervous system can disturb liver function and cause diabetes and hypertension. The damage caused by heavy metals does not end up with the affected person. The harmful effects can be transferred to the person's progenies. Ironically heavy metal pollution is a direct offshoot of our increasing ability to mass produce metals and use them in all spheres of existence. Along with conventional physico- chemical methods, biosystem approachment is also being constantly used for combating metal pollution

Relevância:

100.00% 100.00%

Publicador:

Resumo:

An inappropriate prosthetic fit could cause stress over the interface implant/bone. The objective of this study was to compare stresses transmitted to implants from frameworks cast using different materials and to investigate a possible correlation between vertical misfits and these stresses. Fifteen one-piece cast frameworks simulating bars for fixed prosthesis in a model with five implants were fabricated and arranged into three different groups according to the material used for casting: CP Ti (commercially pure titanium), Co-Cr (cobalt-chromium) or Ni-Cr-Ti (nickel-chromium-titanium) alloys. Each framework was installed over the metal model with all screws tightened to a 10 N cm torque and then, vertical misfits were measured using an optical microscope. The stresses transmitted to implants were measured using quantitative photoelastic analysis in values of maximum shear stress (T), when each framework was tightened to the photoelastic model to a 10 N cm standardized torque. Stress data were statistically analyzed using one-way ANOVA and Tukey`s test and correlation tests were performed using Pearson`s rank correlation (alpha = 0.05). Mean and standard deviation values of vertical misfit are presented for CP Ti (22.40 +/- 9.05 mu m), Co-Cr (66.41 +/- 35.47 mu m) and Ni-Cr-Ti (32.20 +/- 24.47 mu m). Stresses generated by Co-Cr alloy (tau = 7.70 +/- 2.16 kPa) were significantly higher than those generated by CP Ti (tau = 5.86 +/- 1.55 kPa, p = 0.018) and Ni-Cr-Ti alloy (tau =5.74 +/- 3.05 kPa, p = 0.011), which were similar (p = 0.982). Correlations between vertical misfits and stresses around the implants were not significant as for any evaluated materials. (C) 2011 Elsevier Ltd. All rights reserved.

Relevância:

100.00% 100.00%

Publicador:

Resumo:

In this work, the chemical structure, the microstructure and the surface morphology of two non-ferrous materials used in dental implants (Ti-6Al-4V and Co-Cr-Mo) were studied. This was done by chemical analysis, scanning electron microscopy (SEM), energy disperse spectroscopy (EDS), and strength measurements (HV). Metallographic studies reveal that titanium alloy surface present a fine granular binary phase structure, while cobalt alloy present cast dendrite structures with an intense precipitation of carbides. To correlate the macro and microstructure with the mechanical behavior of the material, microhardness measurements were performed. Using the Vickers hardening method, the Ti-6Al-4V alloy yielded strength mean values smaller than the Co-Cr-Mo alloy. Their values are associated to the chemical composition and to the microstructural distribution of these materials. The Ti-6Al-4V alloy presents hardness similar to dental enamel, which suggests better performance as dental implant.

Relevância:

100.00% 100.00%

Publicador:

Resumo:

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

Relevância:

100.00% 100.00%

Publicador:

Resumo:

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Relevância:

100.00% 100.00%

Publicador:

Resumo:

Als paläoklimatische Archive können unter anderem Stalagmiten und Klappen von Ostrakoden herangezogen werden. Bisher gab es noch keine veröffentlichten Ergebnisse räumlich hochaufgelöster Spurenelementverteilungen in einzelnen Ostrakodenklappen. Das gleiche gilt für die Bestimmung radiogener Blei-Isotope in Stalagmiten. Um klimatische Prozesse vergangener Zeiten zu untersuchen, wurde eine neue LA-ICP-MS (Laserablations – Massenspektrometrie mit induktiv gekoppeltem Plasma) Technik für hochaufgelöste in-situ Messungen von Spurenelementen und Bleiisotopen entwickelt. rnrnZunächst wurden geeignete Materialien für die Kalibrierung der Technik untersucht; als Proben dienten die Silikatreferenzgläser BAM-S005-A und BAM-S005B der Bundesanstalt für Materialforschung und –prüfung (BAM). Die Homogenität dieser Referenzgläser wurde mit LA-ICP-MS und den anderen mikroanalytischen Methoden EPMA (Elektronenmikrosonde) und SIMS (Ionensonde) überprüft. Die Ergebnisse zeigten, dass alle Haupt- und die meisten Spurenelemente in beiden Gläsern selbst im Mikrometerbereich homogen verteilt sind. Ausnahmen sind einige Spurenelemente, wie Cs, Cl, Cr, Mo und Ni, die heterogen in den Gläsern verteilt sind. Die Hauptelementzusammensetzung von BAM-S005-A und BAM-S005-B wurde mit Hilfe der EPMA bestimmt, wobei die Ergebnisse die Referenzwerte des BAM-Zertifikats bestätigten. Mit Ausnahme von Sr, Ba, Ce und Pb, stimmten die LA-ICP-MS-Spurenelementwerte mit den zertifizierten Werten innerhalb der angegebenen Fehlergrenzen überein. Gründe für die Diskrepanz der vier oben erwähnten Elemente sind noch unklar, aber sind möglicherweise durch fehlerhafte Referenzwerte zu erklären. Zusätzlich wurden 22 Spurenelemente gemessen, deren Gehalte von BAM nicht zertifiziert wurden. Aufgrund dieser Untersuchungen konnte festgestellt werden, dass beide BAM-Gläser für mikroanalytische Anwendungen geeignet sind.rnrnUm neuartige paläoklimatische Proxies im Calcit von Ostrakoden aus tibetanischen Seesedimenten zu untersuchen, wurde die Spurenelementvariabilität in einzelnen Ostrakodenklappen durch eine neue LA-ICP-MS-Technik bestimmt. Klappen von Ostrakoden der drei Arten (Leucocytherella sinensis Huang, 1982, ?Leucocythere dorsotuberosa Huang, 1982 und ?L. dorsotuberosa f. postilirata sensu Pang, 1985) wurden aus zwei Sedimentkernen des Nam Co Sees auf dem Hochplateau von Tibet gewonnen. Zwei LA-ICP-MS-Varianten, Spot- bzw. Linienanalyse, wurden verwendet, um die Elementkonzentrationen der Spurenelemente Mg, Sr, Ba, U und die der Seltenen Erdelemente (SEE) in den Klappen einzelner Ostrakoden zu bestimmen. Die Ergebnisse zeigten, dass die Linienanalyse präzisere Daten als die Spotanalyse liefert und sie wurde daher vorgezogen. Signifikante Unterschiede in der Spurenelementzusammensetzung zwischen den verschiedenen Arten der Ostrakoden wurden nicht gefunden. Variationen der Elementverhältnisse Mg/Ca und Sr/Ca in den Klappen stimmen mit veröffentlichten Seenspiegelschwankungen während des Holozäns überein, was zeigt, dass Mg- und Sr-Messungen in den Ostrakoden zur Untersuchung paläohydrochemischer Prozesse in diesem Gebiet herangezogen werden kann. Die gute Korrelation, die in dieser Arbeit zwischen Ba/Ca und Sr/Ca gefunden wurde, ist ein Hinweis darauf, dass der Einbau von Ba und Sr in die Klappen durch den gleichen Mechanismus erfolgte. Eine mögliche Beziehung zwischen dem U/Ca-Verhältnis in den Ostrakoden und den Redoxbedingungen auf dem Boden des Sees in der Vergangenheit wird diskutiert. Relativ geringe und konstante La/Ca-Verhältnisse wurden festgestellt, deren Ursache möglicherweise entweder auf der SEE-Charakteristik des Seewassers, auf biologischen Prozessen in den Ostrakoden oder auf Kontamination von Fe-Mn und/oder organischen Substanzen beruhen. Weitere Untersuchungen an Proben aus diesem Gebiet, speziell Klappen von lebenden Ostrakoden, sind notwendig, um den Gehalt von Ba, U und den SEE in Ostrakoden als paläoklimatische Proxies von Umweltbedingungen zu verwenden.

Relevância:

100.00% 100.00%

Publicador:

Resumo:

Si è valutata l'efficienza di estrazione di metalli pesanti (Al, Zn, Pb, V, Cr, Cu, Ti, Co, Cd, Ni) da soluzioni ottenute da leaching acido di fly ash da termovalorizzatore. L'efficienza è stata stimata in funzione del pH e del tempo (esperimenti di 24 h e 3 h) e tramite l'utilizzo di un agente chelante (EDTA). Si è dimostrata l'efficienza dell'esperimento di 3 h, che si traduce in un beneficio economico in quanto si ottiene un elevato grado di estrazione in minor tempo.

Relevância:

100.00% 100.00%

Publicador:

Resumo:

At Site 585 of Deep Sea Drilling Project Leg 89 more than 500 m of volcaniclastic to argillaceous middle-Late Cretaceous sediments were recovered. Analyses by X-ray diffraction (bulk sediment and clay fraction), transmission electron microscopy, molecular and atomic absorption, and electron microprobe were done on Site 585 samples. We identify four successive stages and interpret them as the expression of environments evolving under successive influences: Stage 1, late Aptian to early Albian - subaerial and proximal volcanism, chiefly expressed by the presence of augite, analcite, olivine, celadonite, small and well-shaped transparent trioctahedral saponite, Al hydroxides, Na, Fe, Mg, and various trace elements (Mn, Ni, Cr, Co, Pb, V, Zn, Ti). Stage 2, early to middle Albian - submarine and less proximal volcanic influence, characterized by dioctahedral and hairy Mg-beidellites, a paucity of analcite and pyroxenes, the presence of Mg and K, and local alteration of Mg-smectites to Mg-chlorites. Stage 3, middle Albian to middle Campanian - early marine diagenesis, marked by the development of recrystallization from fleecy smectites to lathed ones (all of alkaline Si-rich Fe-beidellite types), by the development of opal CT and clinoptilolite, and by proximal to distal volcanic influences (Na parallel to Ti, K). Local events consist of the supply of reworked palygorskite during the Albian-Cenomanian, and the recurrence of proximal volcanic activity during the early Campanian. Stage 4, late Campanian to Maestrichtian - development of terrigenous supply resulting from the submersion of topographic barriers; this terrigenous supply is associated with minor diagenetic effects and is marked by a clay diversification (beidellite, illite, kaolinite, palygorskite), the rareness of clay recrystallizations, and the disappearance of volcanic markers.

Relevância:

100.00% 100.00%

Publicador:

Resumo:

The major element geochemistry of basalts recovered from Leg 83, Hole 504B, shows the typical features of midocean ridge basalts (MORB). The range of variation in their composition, together with the behavior of compatible trace elements (Co, Ni, Cr), indicate the well-known relative abundance of minerals that crystallize from these basaltic liquids: plagioclase, olivine, pyroxene, and spinel in decreasing abundance. The hygromagmaphile (or LILE or incompatible) elements are extremely depleted in light rare earths. Nevertheless, some units show flat and enriched REE patterns. These patterns, together with the values of the La/Ta ratio, are interpreted in terms of local mantle heterogeneity.

Relevância:

100.00% 100.00%

Publicador:

Resumo:

Chemical analyses have been carried out on 40 samples from the sediment surface and 210 samples from cores that were taken from the edge of the African continental block at the Arabian Sea (coasts of Somalia and Kenya, from Cape Guardafui to Mombasa) on the occasion of the Indian Ocean Expedition of the German research vessel "Meteor" during the years 1964/65. The carbonate content shows its maximum on the northern part of the continental shelf of Africa, where fossil reef debris furnish the detritic portion of carbonate. In the southern part of the continental shelf of Africa the portion of carbonate is low, as it is heavily diluted by the non-carbonatic detritus. It is also in the deep-sea that a lower carbonate content is encountered below the calcite compensation depth. Trace elements in the carbonates: On the shelf and in its vicinity Sr and Mg are enriched. The enrichment has been brought about by the portion of reef debris, as this latter contains aragonite (enrichment of Sr) as well as high-magnesium calcite. The greatest part of the slope contains carbonates that are poor in trace elements and mainly made up of foraminifera (and of coccoliths). Below the carbonate compensation depth another enrichment of Mg takes place in the carbonates, which is probably due to a selective dissolution of calcite in comparison to dolomite. The iron and manganese contents of the carbonates are high (iron higher in coast proximity, manganese higher in the depth), but not genuine, as they come about in the course of the extraction of the carbonates as a result of the dissolution of authigenic Mn-Fe-minerals. Non-carbonatic portion of the sediments: In coast proximity an enrichment of quartz comes about. Within the quartz-rich zone it is the elements V, Cr, Fe, Ti, and B that have been enriched in the non-carbonatic components. This enrichment must be attributed to an elevated content of heavy minerals. In the case of Ti and Fe the preliminary enrichment brought about by processes of lateritisation on the continent plays a certain role. Toward the deep-sea an enrichment of the elements Mn Ni, Cu, and Zn takes place; these enrichments must be explained by authigenic Mn-Fe-minerals. Within the Mn-rich zone a belt running parallel to the coast stands out that shows an increased Mn-enrichment. However, this increase in enrichment does not apply to the elements Ni, Cu, and Zn. It is probable that this latter increased enrichment comes about as a result of the migration of manganese to the sediment surface. (Within the sediments there prevail reductive conditions, in the presence of which Mn is capable of migration, whereas at the sediment surface its precipitation comes about under oxidizing conditions). The quantity of organic matter mainly is dependent on grain size and on the rate of sedimentation. On the shelf an impoverishment of organic matter is to be encountered, as the sediments are coarse-grained. In the depth the impoverishment must be explained on the strength of a small rate of sedimentation. Between those two ranges organic substance is enriched. P and N show an enrichment in comparison to Corg with this applying all the more the smaller the absolute quantity of Corg is. In this particular case one has to do with an enrichment coming about during the diagenetic processes of organic matter. A comparison with the sediments from the Indian and Pakistani continental border in Arabian Sea shows as follows: on the African continental border the coarse detrital material has been transported farther out to deep-sea, which has something to do with the greater inclination of the surface of sedimentation. Carbonate is found in greater abundance on the African side. Its chemical composition is influenced by reef-debris which is missing by Indian-Pakistani side. The content of organic matter is lower on the African side. Contrary to that, the enrichments of N and P compared to organic matter are of an equal order of magnitude on both sides of the Arabian Sea.

Relevância:

100.00% 100.00%

Publicador:

Resumo:

We measured the chemical composition of 100 samples from the 250-m sediment sequence retrieved from Ocean Drilling Program Site 1256 in the Guatemala Basin using a newly developed microwave-assisted acid digestion protocol followed by inductively coupled plasma-atomic emission spectroscopy (ICP-AES) analysis. We compared these data gathered onshore to the results from the flux fusion prepared samples analyzed by shipboard ICP-AES during the leg and published in the Leg 206 Initial Reports volume, as well as to 35 randomly selected samples that were prepared by flux fusion at Boston University and analyzed by ICP-AES. Comparison of the newly developed acid digestion protocol to shore-based flux fusion demonstrates that the microwave-assisted acid technique yields a complete digestion, and because this procedure includes boric acid, it is safe for use with HF acid as boric acid neutralizes excess HF. The precision for nearly all elements in shore-based acid digestions is better than 3% of the measured values, including for elements such as Ni, Cr, and V, which are typically difficult to measure in biogenic-rich sediments. The shore-based flux fusions, while better than shipboard reported precision values (as expected), has precision better than 3% of their respective measured values for all major elements (Si, Al, Ti, Fe, Mn, Ca, Mg, Na, and K) and several trace elements (Ba and Sr). Results for P, Cr, Ni, V, Sc, and Zr are better than 5% of their measured values. Not only does the newly developed acid digestion provide better analytical results than the typical flux fusion method, the shore-based acid procedure also exhibits downhole lithologic and chemical characteristics similar to the shipboard flux fusion prepared results. These results confirm that the current shipboard methods are adequate for first-order geochemical interpretations and that the microwave-assisted acid digestion holds great potential to be the primary technique of preparing sediments on future Integrated Ocean Drilling Program expeditions.