高圧鉱物の熱膨張率測定と熱力学的データに基づく高圧相平衡図の精密化

金沢大学理学部研究課題/領域番号60540519, 研究期間(年度):1985出典：研究課題「高圧鉱物の熱膨張率測定と熱力学的データに基づく高圧相平衡図の精密化」課題番号60540519（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-60540519/）を加工して作

Superconductivity suppression of Ba0.5K0.5Fe2-2xM2xAs2 single crystals by substitution of transition-metal (M = Mn, Ru, Co, Ni, Cu, and Zn)

We investigated the doping effects of magnetic and nonmagnetic impurities on the single-crystalline p-type Ba0.5K0.5Fe2-2xM2xAs2 (M = Mn, Ru, Co, Ni, Cu and Zn) superconductors. The superconductivity indicates robustly against impurity of Ru, while weakly against the impurities of Mn, Co, Ni, Cu, and Zn. However, the present Tc suppression rate of both magnetic and nonmagnetic impurities remains much lower than what was expected for the s\pm-wave model. The temperature dependence of resistivity data is observed an obvious low-T upturn for the crystals doped with high-level impurity, which is due to the occurrence of localization. Thus, the relatively weak Tc suppression effect from Mn, Co, Ni, Cu, and Zn are considered as a result of localization rather than pair-breaking effect in s\pm-wave model.Comment: 8 pages, 9 figures, to be published in Phys. Rev.

微小量鉱物の熱測定の高精度化・迅速化

金沢大理学部1.前年度に引き続き示差走査熱量計を用いて微少量の鉱物の比熱が測定された。この測定データは、パーソナル・コンピュータを主体とするデータ処理システムによって直ちに解析され、比熱測定の精度が従来の同種の測定法よりも向上し、また測定・計算に要する時間が大幅に短縮化した。高温高圧下で安定な【Mg_4】【Si_4】【O_(12)】-【Mg_3】【Al_2】【Si_3】【O_(12)】系ザクロ石の比熱測定の一環として、前年度には【Mg_3】【Al_2】【Si_3】【O_(12)】及び58%【Mg_4】【Si_4】【O_(12)】-42%【Mg_2】【Al_2】【Si_3】【O_(12)】組成のザクロ石の比熱が測定されたが、今年度にはさらに両者の中間の二種の組成のザクロ石(【Mg_4】【Si_4】【O_(12)】成分の固溶量が18%と41%)が新たに測定された。全体の比熱データを総合すると、この系では【Mg_4】【Si_4】【O_(12)】成分の固溶量に比熱がほとんどよらないことが明らかになった。この測定データからグリュナイゼンパラメータ、デバイ温度が計算された。2.下記の珪酸塩・ゲルマン酸塩の高圧相転移に伴う転移エンタルピーが測定された。(1)MnSi【O_3】のロードナイト→輝石→ザクロ石転移(60年度に行われた)。(2)CaGe【O_3】の珪灰石→ザクロ石→ペロブスカイト転移(3)CdGe【O_3】の準輝石→ザクロ石→イルナナイト→ペロブスカイト転移(4)【Mg_4】【Si_4】【O_(12)】-【Mg_3】【Al_2】【Si_3】【O_(12)】系の輝石→ザクロ石転移これらの転移エンタルピーから計算された相境界線と高圧相平衡実験により独立に決定された相境界線が比較され、どの場合も実験誤差範囲内で良い一致を示すことが確認された。MnSi【O_3】、CaGe【O_3】、CdGe【O_3】の転移エンタルピーのデータはマントルで起こるMgSi【O_3】の同種の転移のデータを推定する上で貴重である。今後MgSi【O_3】自身のザクロ石→イルナナイト→ペロブスカイト転移に伴う転移エンタルピーを測定することが必要であり、試科の合成、測定を計画中である。1. Heat capacities of high-pressure silicate minerals were measured by the differencial scanning calorimeter which was installed by the grant-in-aid for scientific research. The data processing system using the personal computor was made for rapid and accurate calculation of the heat capacity measured by the differencial scanning calorimeter. Garnet solid solutions containing pyroxene components are stable in the pressure-temperature conditions in the mantle transition zone. Heat capacities of the garnet solid solutions in the system - , which represent the garnets in the transition zone, were measured by the present heat capacity measurement system. It was observed that heat capacity of the garnet solid solution at each temperature changed very little with increasing component. The Gruneisen parameter and Debye temperature of the garnet solid solutions were estimated from the heat capacity data.2. Enthalpies of silicates and germanates stable at high pressures were measured. Enthalpies of transition of the silicates and germanates were obtained for the following systems:(1) rhodonite-clinopyroxene-garnet transitions in MnSi , (2) wollastonite-garnet-perovskite transitions in CaGe , (3) pyroxenoid-garnet-ilmenite-perovskite transitions in CdGe , (4) pyroxene-garnet transition in the system - .Phase boundaries for the above transitions were calculated from the measured enthalpies.They were almost consistent with the boundaries determined by the phase equilibrium experiments. It was established that the pyroxene(or pyroxenoid)- garnet transitions have generally gentle positive dP/dT slopes, while the ilmenite (or garnet)-perovskite transitions have negative slopes.研究課題/領域番号:60840023, 研究期間(年度):1985 – 1986出典：研究課題「微小量鉱物の熱測定の高精度化・迅速化」課題番号60840023（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/report/KAKENHI-PROJECT-60840023/608400231986kenkyu_seika_hokoku_gaiyo/）を加工して作

高圧珪酸塩鉱物の熱測定による相平衡図の精密化とマントル構造への応用

金沢大学理学部本研究の期間に行なわれた研究の内、主要な成果について以下に要点を述べる。1.Mg_2Sio_4-Fe_2Sio_4系のオリビン、変形スピネル及びスピネルに関して、それらの間の転移のエンタルピ-を測定した。そのデ-タを基にしてこの系の相平衡図を熱力学的手法で計算し、高圧実験による相平衡図と比較検討した。この計算による相手衡図は、従来よく使用されてきたRi-ngwood & Major(1970)及びKawada(1977)の高圧実験による相平衡図とは変形スピネルとスピネルの領域に大きな違いがあり、最近精密な相平衡実験によって決められたKatsura & Ito(1989)の結果とよい一致を示した。その結果、マントルでのオリビン一変形スピネル転移は深さ約390〜410kmで、変形スピル-スピネル転移は約490〜540kmで起こること、深さ390、650kmの温度は1400、1600℃と見積られた。2.Mg_4Si_4O_-Mg_3Al_2Si_3O_系の輝石-ザクロ石転移に関する転移エンタルピ-が測定され、相平衡図が計算された。その結果は高圧実験に基づく相平衡図とほぼ一致した。また輝石-ザクロ石転移は深さ約300〜500kmで徐々に進行し、鋭い地震波速度不連続を与えないことが確立された。3.焼結ダイヤモンドを超硬合金アンビルの中央に埋め込んだ新型ブリジマンアンビルを使用して、最高18GPaまでの高温高圧実験が行われた。先端径26mmのブリジマンアンビルとしては最高の圧力が発生できたと考えられる。このアンビルを用いて、Zn_2SiO_4変形スピネル→ZnSiO_3イルメナイト+ZnOの高圧相境界線が決定された。4.ZnSiO_3、Ni_2Sio_4の高圧相転移のエンタルピ-測定が行われ、輝石-イルメナイト転移(ZnSiO_3)とスピネル分解反応(Ni_2SiO_4)の相境界線が熱学力計算により決定された。The important scientific results of this research project are summarized as follows.1. Enthalpies of the olivine-modified spinel-spinel transitions in the system Mg_2SiO_4-Fe_2SiO_4 were measured by high temperature calorimetric techniques. The phase diagrams calculated form the present thermochemical data are not well consistent with those by Ringwood and Major (1970) and Kawada (1977), but agree very well with that determined with precise high pressure experiments by Katsura and Ito (1989). From the calculated phase diagrams, it is concluded that the olivine-modified spinel transition occurs at about 390-410 km in the mantle, while the modified spinel-spinel transition at about 490-540 km. Temperatures at 390 and 650 km are estimated to be 1400 and 1600 ﾟC, respectively.2. Enthalpy of the pyroxene-garnet transition in the system Mg_4Si_4O_-Mg_3Al_2 Si_3O_ was measured by the same calorimetric techniques. The calculated phase diagram was in good agreement, with that by high pressure experiments by Akaogi and Akimoto (1977), when the pressure scale was revised. It was concluded from the phase diagram that the pyroxene-garnet transition in the mantle occurs gradually with depth in the depth range of about 300-500 km and shows no sharp seismic velocity discontinuity.3. High pressures over 18 GPa were generated by using new Bridgman-anvils (26 mm in diameter) with sintered diamond tips. The transition of beta-Zn_2SiO_4 to ZnSiO_3 ilmenite plus ZnO was examined using these new anvils.4. From the measured enthalpies of the pyroxene-ilmenite transition in ZnSiO_3 and of the disproportionation of Ni_2SiO_4 spinel, these phase equilibrium boundaries were calculated thermodynamically.研究課題/領域番号:62540618, 研究期間(年度):1987 – 1989出典：研究課題「高圧珪酸塩鉱物の熱測定による相平衡図の精密化とマントル構造への応用」課題番号62540618（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/report/KAKENHI-PROJECT-62540618/625406181989kenkyu_seika_hokoku_gaiyo/）を加工して作

非等軸晶糸ザクロ石の高圧合成と結晶構造解析

金沢大学理学部研究課題/領域番号:56740347, 研究期間(年度):1981出典：「非等軸晶糸ザクロ石の高圧合成と結晶構造解析」研究成果報告書　課題番号56740347（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-56740347/）を加工して作

焼結ダイヤモンド埋込型アンビルの試作と超高圧高温の発生

学習院大学理学部 / 金沢大学理学部超高圧高温実験は、地球・惑星科学においてだけでなく、新物質開発においても不可欠の技術である.現在の超高圧実験には超硬合金製のアンビルが広く用いられているが、その材料強度から発生圧力には限界がある.本研究では、より硬い素材であるダイヤモンド焼結体を用いてアンビルを試作し、より高い圧力を発生させて、超高圧高温実験法を確立することを目的とした.まずダイヤモンド焼結体を超硬合金アンビルの中央に埋め込んだ構造のブリジマンアンビル(先端径26mmと20mmの2種)を試作した.またこのブリジマンアンビルを加圧するための一軸圧縮プレス(常用600トン)を製作した.これらの装置を用いて得た主要な成果は以下の通りである.1.室温において約20.5GPaまでの圧力発生に成功した.これは従来の超硬合金製ブリジマンアンビルでの最高圧(約14GPa)を大きく上回るものである.さらに高圧下で最高1400℃までの高温を発生させて定常的に相転移実験を行う技術の確立に成功した.2.この技術を用いて、以下の結果を得た.1)KAISi_3O_8長石がK_2Si_4O_9 wadeite+AI_2SiO_5kyanite+SiO_2に分解し、KAISi_3O_8hollanditeに再結合する相境界を決定した.2)CaAl_2O_4カルシウムフェライト相の安定領域を決定した.3)CaFeSi_2O_6単斜輝石がCaSiO_3ペロブスカイト+Fe_2SiO_4スピネル+SiO_2に分解する相境界を決定した.これらの高圧相転移は、下部マントルの絋物構成を抽定する上で重要である.3.関連する研究として、TiO_2のルチル型→αPbO_2型転移の平衡相境界を高圧高温x線回折技術を用いて決定した.この相境界線は高温における圧力較正点に用いられる.The purpose of this research project is to develop anvils with sintered diamond cores and to generate high pressures and high temperatures using the new anvils. We have developed two kinds of Bridgman anvils which consist of tungsten carbide with sintered diamond core. The diameters of tlie anvils are 26 and 20 mm. We have also constructed a 600-ton press, which is used to compress the Bridgman anvils to generate high pressures. Using these apparatus, the following results have been obtained during this project term.1. We have successfully generated pressure up to about 20.5 GPa using the new anvils. This generated pressure is much higher than those attained by Bridgman anvils made of tungsten carbide. The new anvils have also been used for high pressure high temperature experiments up to 17 GPa and 1400 ﾟC.2. The following phase transition experiments have been caried out. Phase boundaries in KAlSi_3O_8 feldspar to K_2Si_4O_9 wadeite + Al_2SiO_5 kyanite + SiO_2 coesite (or stishovite) and further to KAlSi_3O_8 hollandite have been determined. Stability field of CaAl_2O_4 calcium ferrite has been examined. The decomposition boundary of CaFeSi_2O_6 clinopyroxene to CaSiO_3 perovskite + Fe_2SiO_4 spinel +SiO_2 stishovite has also been determined. These phase boundaries are of geophysical and geochemical importance in the lower mantle.3. As a related topic, the rutile-alphaPbO_2 transition boundary in TiO_2 has accurately been determined by in situ x-ray diffraction techniques at high pressure and high temperature. This boundary is important for pressure calibration at high temperatures.研究課題/領域番号:01840029, 研究期間(年度):1989 – 1991出典：研究課題「焼結ダイヤモンド埋込型アンビルの試作と超高圧高温の発生」課題番号01840029（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/report/KAKENHI-PROJECT-01840029/018400291991kenkyu_seika_hokoku_gaiyo/）を加工して作

Hip preserving surgery with concentrated autologous bone marrow aspirate transplantation for the treatment of asymptomatic osteonecrosis of the femoral head: retrospective review of clinical and radiological outcomes at 6 years postoperatively

BackgroundWe had previously established concentrated autologous bone marrow aspirate transplantation (CABMAT), a one-step, low-invasive, joint-preserving surgical technique for treating osteonecrosis of the femoral head (ONFH). The present study aimed to evaluate the effects of CABMAT as a hip preserving surgical approach, preventing femoral head collapse in asymptomatic ONFH.MethodsIn total, 222 patients (341 hips) with ONFH were treated with CABMAT between April 2003 and March 2013. Based on magnetic resonance imaging, we determined that 119 of these patients had bilateral asymptomatic ONFH (238 hips), and 38 further patients had unilateral asymptomatic ONFH (38 hips). In this series, we retrospectively examined 31 hips in 31 patients with unilateral asymptomatic ONFH treated surgically between 2003 and 2012 and followed up for more than 2 years. Clinical and radiological evaluation were performed immediately before the procedure and at the final follow-up. The two-year follow-up rate among patients with unilateral ONFH was 82% (31/38). Therefore, the present study included 31 patients (19 males and 12 females), with a mean age and follow-up period of 40 and 5.8 years, respectively. Of the 31 asymptomatic hips, 5, 6, 10, and 10 had osteonecrosis of types A, B, C1, and C2, respectively. The diagnosis, classification, and staging of ONFH were based on the 2001 Japanese Orthopaedic Association (JOA) classification.ResultsSecondary collapse of the femoral head was observed in 6/10 hips and 5/10 hips with osteonecrosis of types C1 and C2, respectively. Total hip arthroplasty was performed in 9.6% of patients (3/31 hips), at an average of 33 months after surgery. Clinical symptoms improved after surgery, and the secondary collapse rate at a mean of 5.8 years after CABMAT was lower than that reported in several previous studies on the natural course of asymptomatic ONFH.ConclusionsEarly diagnosis of ONFH (i.e., before femoral head collapse) and early intervention with CABMAT could improve the clinical outcome of corticosteroid and alcohol-induced ONFH

Thermoelastic Properties of Ringwoodite [Fe_x,Mg_(1-x)]_2SiO_4: Its Relationship to the 520 km Seismic Discontinuity

We combine density functional theory (DFT) within the local density approximation (LDA), the quasiharmonic approximation (QHA), and a model vibrational density of states (VDoS) to calculate elastic moduli and sound velocities of gamma-[Fe_x,Mg_(1-x)]_2SiO_4 (ringwoodite), the most abundant mineral of the lower Earth's transition zone (TZ). Comparison with experimental values at room-temperature and high pressure or ambient-pressure and high temperature shows good agreement with our first-principles findings. Then, we investigate the contrasts associated with the beta-to-gamma-[Fe_x,Mg_(1-x)]_2SiO_4 transformation at pressures and temperatures relevant to the TZ. This information offers clearly defined reference values to advance the understanding of the nature of the 520 km seismic discontinuity.Comment: 29 pages, 6 figures, 2 tables. Under Revie