1,720,996 research outputs found
地球規模の二酸化炭素循環システムにおける地球深部物質の役割
Get PDF本研究は,地球上の二酸化炭素循環を理解するために,地球深部起源岩石中に炭酸塩鉱物などの形で固定される二酸化炭素成分とそれをモニターするために二酸化炭素成分と同時に固定される元素を明らかにすることを目的に行なわれた.
まず,(1)海洋底に直接露出している地球深部起源岩石,(2)糸魚川-青海地域の変成岩,(3)構造運動によって地球深部岩石が露出した北海道幌満かんらん岩体に対して特に検討した.元素モニターを行なうために,炭酸塩鉱物や通常の造岩鉱物中の微量元素成分を金沢大学設置のLA-ICPMSを用いて測定する方法の開発を行なった.そして,これらの方法を利用して,測定を行なった.
1のサンプルに関しては,光学顕微鏡観察,電子顕微鏡観察により,炭酸塩鉱物の産状,種類によって2ステージある事を明らかにし,それぞれの微量元素の特徴としては,Sr, Uに関して大きなシンクとなる可能性があるが,その他の元素についてはほとんど含まれていない事を明らかにした(投稿準備中).また,ある種の岩石の微量元素パターンに特殊な特徴があることを指摘し,その特徴はこの岩石が流体の影響を受けているためであることを指摘した(文献1,Nakamura et al.,2007) 2のサンプルに関しては,炭素を多く含む試料を含めて,構成鉱物の微量元素の特徴を明らかにし,これまで知られていない特殊な化学的特徴を持つ流体が関与していること,その発生メカニズムについて議論した(文献3,Morishita et al.,2007,Island Arc).3のサンプルに関しては,二酸化炭素ではないが,ほとんど微量元素を含まない流体が付加したことを明らかにした(文献2,Morishita et al.,2007,Lithos).研究課題/領域番号:17740349, 研究期間(年度):2005 – 2006出典：「地球規模の二酸化炭素循環システムにおける地球深部物質の役割」研究成果報告書 課題番号17740349
（KAKEN：科学研究費助成事業データベース（国立情報学研究所））
（https://kaken.nii.ac.jp/ja/grant/KAKENHI-PROJECT-17740349/)を加工して作成金沢大学理工研究域research repor
Going Beyond Counting First Authors in Author Co-citation Analysis
Get PDFThe present study examines one of the fundamental aspects of author co-citation analysis (ACA) - the way co-citation
counts are defined. Co-citation counting provides the data on which all subsequent statistical analyses and mappings
are based, and we compare ACA results based on two different types of co-citation counting - the traditional type that
only counts the first one among a cited work's authors on the one hand and a non-traditional type that takes into
account the first 5 authors of a cited work on the other hand. Results indicate that the picture produced through this non-traditional author co-citation counting contains more coherent author groups and is therefore considerably clearer. However, this picture represents fewer specialties in the research field being studied than that produced through the traditional first-author co-citation counting when the same number of top-ranked authors is selected and analyzed. Reasons for these effects are discussed
Maturing processes of deeper part of the Island arc: Diversity of crust-mantle boundary and their origins in the Albania Ophiolite
Get PDF本研究では,本来直接観察・サンプル採取を行えない日本列島のような島弧深部相当(最上部マントル/下部地殻)でのプロセスを理解するために,アルバニアなどに露出するオフィオライトに着目し,野外調査および,採取した試料の解析を行った。その結果, 島弧深部相当,特にマントル相当の岩相について下位から上位にかけて
(1)中央海嶺とは異なり,流体の流入を伴うようなマグマ活動に関連した岩相が上位にかけて増加すること
(2)かんらん岩層の上位には,シリカの付加が普遍的に観察されること
(3)これまで中央海嶺環境で形成されて来たと考えられていた西側部分について,一部が島弧でのマグマ活動および加水作用をうけていることを明らかにした。In order to understand the maturing processes in the deeper part of the Island arc systems, we examined arc-related ophiolites and related rocks from all over the world, particularly in the Mirdita ophiolite, Albania. Based on our filed works coupled with geochemical analyses, we concluded the maturing processes in the deeper part of the Island arc system as follows:
(1) Effect of influx melting due to infiltration of hydrous fluids/melts are increased toward the upper section of the peridotite section, i.e., the upper most mantle section
(2) Silica-enrichment is caused by interaction with slab-derived hydrous fluids
(3) Peridotite massifs in the Western Mirdita Ophiolite, which had been interpreted to be of mid-ocean ridge origin, were originally formed at mid-ocean ridge setting, but was also affected by arc-related hydrous fluids/melts, resulting in the formation of fertile peridotite, such as amphibole-rich peridotites.研究課題/領域番号:21403010, 研究期間(年度):2009-2012出典：研究課題「島弧深部熟成過程:アルバニア・オフィオライトの地殻: マントル境界時空変動」課題番号21403010
（KAKEN：科学研究費助成事業データベース（国立情報学研究所））
（https://kaken.nii.ac.jp/report/KAKENHI-PROJECT-21403010/21403010seika/）を加工して作成research repor
Variations on the Author
Get PDF“Variations on the Author” discusses two of Eduardo Coutinho’s recent films (Um Dia na Vida, from 2010, and Últimas Conversas, posthumously released in 2015) and their contribution to the general question of documentary authorship. The director’s filmography is characterized by a consistent yet self-effacing form of authorial self-inscription: Coutinho often features as an interviewer that rather than express opinions propels discourses; an interviewer that is good at listening. This mode of self-inscription characterizes him as an author who is not expressive but who is nonetheless markedly present on the screen. In Um Dia na Vida, however, Coutinho is completely absent form the image, while Últimas Conversas, on the contrary, includes a confessional prologue that moves the director from the margins to the center of his films. This article examines the ways in which these works stand out in the filmography of a director who offers new insights into the notion of cinematic authorship
Carbon cycling in the subduction zones deduced from in-situ Carbon isotope analyses
Get PDFハワイ大学設置のSIMSを用いて、グラファイトの局所炭素同位体比分析の分析手法を確立した。この手法を用いて、高圧変成岩、接触変成岩、ヒスイ輝岩、グラファイトを含むかんらん岩捕獲岩の分析を行った。高圧変成岩類、接触変成岩類は、炭質物中の不純物の影響により良いデータが得られなかった。ヒスイ輝岩のデータから、ヒスイが形成される沈み込み帯初期には、マントル値と同程度の炭素同位体比を含む流体が関与していることが明らかになった。かんらん岩捕獲岩中のグラファイトからは、生物起源を示唆する軽い同位体比が得られた。マントル中でのダイヤモンドが形成との関連を示唆する。In-situ carbon isotopic analyses using SIMS was developed at the University of Hawaii. I analyzed 4 different natural samples: (1) high-pressure metamorphic rocks, (2) contact metamorphic rocks, (3) jadeites, and (4) graphite-bearing mantle xenoliths. Unfortunately, I was not able to reliable date from (1) and (2) because of matrix effects of silicate inclusions within carbon-bearing phases in these samples. Graphite in jadeites has similar carbon isotopic compositions to mantle value. This suggests that fluids with mantle-like carbon isotopic compositions are responsible for the formation of jadeite at the beginning of subduction. Graphite in the mantle xenolith has light-carbon isotopic compositions. This suggest the carbon in the sample was of biogenic origin. This graphite will provide us useful information on origin of diamond in the mantle.研究課題/領域番号:23654185, 研究期間(年度):2011-2012出典：研究課題「沈み込み帯での炭素循環新情報発信へ：微少量グラファイトの局所炭素同位体比分析」課題番号23654185
（KAKEN：科学研究費助成事業データベース（国立情報学研究所））
（https://kaken.nii.ac.jp/report/KAKENHI-PROJECT-23654185/23654185seika/）を加工して作成research repor
Appropriate Similarity Measures for Author Cocitation Analysis
Get PDFWe provide a number of new insights into the methodological discussion about author cocitation analysis. We first argue that the use of the Pearson correlation for measuring the similarity between authors’ cocitation profiles is not very satisfactory. We then discuss what kind of similarity measures may be used as an alternative to the Pearson correlation. We consider three similarity measures in particular. One is the well-known cosine. The other two similarity measures have not been used before in the bibliometric literature. Finally, we show by means of an example that our findings have a high practical relevance.information science;Pearson correlation;cosine;similarity measure;author cocitation analysis
Maturing processes of act MOHO deduced from ophiolites
Get PDF本研究は，島弧成熟過程による島弧深部の発達を島弧誕生期（北オマーンオフィオライト），青年期（ミルディータオフィオライト），成熟期（タルキートナ岩体）と設定し検討した。その結果，マントル相当部分では，流体流入によるメルト成分が枯渇したかんらん岩が普遍的に分布していること，輝岩類が多く形成されていることから輝石成分の付加が島弧深部では起きていることが明らかとなった。また，下部地殻相当中に変成作用によって形成されたと解釈される超苦鉄質岩がしばしば観察されることから，これらの成因と下部地殻から超苦鉄質成分が剥がれ落ちる作用との関連性が指摘される。I summarize results from two ophiolites (the northern Oman ophiolite of Oman and the Mirdita Ophiolite of Albania) and ophiolitic localities (the Talkeetna massif, Alaska) in order to investigate the maturing processes of arc systems, such as Nascent, Young and Mature stages, respectively. The main conclusions are as follows: (1) the high frequency of highly refractory harzburgite (+dunite and chromitite) caused by influx of slab-derived fluids, (2) silica enrichments resulting in increasing of pyroxenites in peridotites. These can be good indicators of arc-related magmatic modifications in the mantle. In Mature stage (Talkeetna), ultramafic rocks are formed by metamorphism from plagioclase-bearing crustal rocks. These rocks can be related those are delaminated from the lower crust part to the mantle.研究課題/領域番号:25302012, 研究期間(年度):2013-04-01 - 2016-03-31出典：研究課題「島弧深部の成熟過程解明に向けて: 青年期から成人期のモホ面近傍の現場検証」課題番号25302012
（KAKEN：科学研究費助成事業データベース（国立情報学研究所））
（https://kaken.nii.ac.jp/report/KAKENHI-PROJECT-25302012/25302012seika/）を加工して作成金沢大学理工研究域地球社会基盤学系research repor
Dispelling the Myths Behind First-author Citation Counts
Get PDFWe conducted a full-scale evaluative citation analysis study of scholars in the XML research field to explore just how different from each other author rankings resulting from different citation counting methods actually are, and to demonstrate the capability of emerging data and tools on the Web in supporting more realistic citation counting methods. Our results contest some common arguments for the continued
use of first-author citation counts in the evaluation of scholars, such as high correlations between author rankings by first-author citation counts and other citation
counting methods, and high costs of using more realistic citation counting methods that are not well-supported by the ISI databases. It is argued that increasingly available digital full text research papers make it possible for citation analysis studies to go beyond what the ISI databases have directly supported and to employ more
sophisticated methods
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