著者

ネスポロ マッシモ 草野 圭弘 松本 崧生 中井 泉 阿部 善也

出版者

日本結晶学会

雑誌

日本結晶学会誌 (ISSN:03694585)

巻号頁・発行日

vol.51, no.1, pp.133-139, 2009-02-28 (Released:2010-10-01)

著者

富崎 孝司

出版者

日本結晶学会

雑誌

日本結晶学会誌 (ISSN:03694585)

巻号頁・発行日

vol.48, no.3, pp.182-188, 2006-06-30 (Released:2010-09-30)

参考文献数

18

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The ultimate goal of diffraction experiments is to collect complete datasets as rapid as possible with good statistics. It is of atmost important that we should make the priority and objective of experiments clear to complete neccessary data acquisition in a fixed, short beamtime. Needless to say, we should select best beamlines for our objective in order to minimise time loss and to maximise the efficiency of the beamlines. Strategies of data acquisition on beamline X06SA at the Swiss Light Source is disscussed.

著者

吉井 賢資 池田 直 松尾 祥史 森 茂生

出版者

日本結晶学会

雑誌

日本結晶学会誌 (ISSN:03694585)

巻号頁・発行日

vol.51, no.2, pp.162-168, 2009-04-30 (Released:2010-11-05)

参考文献数

25

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The rare-earth iron oxides RFe2O4 (R = Y, Ho-Lu) have a rhombohedral crystal structure, consisting of an alternating stacking of triangular lattices of R, Fe and O ions. Recently, we have proposed that this system shows a new mechanism of ferroelectricity ; the ferroelectric state originates from a polar charge-ordered structure of Fe2+ and Fe3+ on a triangular lattice. In this article, a review is given on the details of this ferroelectricity, which were revealed by measurements of synchrotron X-ray diffraction and dielectric properties of one of the RFe2O4 oxides, LuFe2O4.

著者

表 和彦 藤縄 剛

出版者

日本結晶学会

雑誌

日本結晶学会誌 (ISSN:03694585)

巻号頁・発行日

vol.39, no.Supplement, pp.188, 1997-11-13 (Released:2010-09-30)

被引用文献数

1

著者

富岡 尚敬 Phase 2キュレーション高知チーム

出版者

日本結晶学会

雑誌

日本結晶学会誌 (ISSN:03694585)

巻号頁・発行日

vol.65, no.4, pp.216-217, 2023-12-15 (Released:2023-12-20)

参考文献数

9

著者

保倉 明子

出版者

日本結晶学会

雑誌

日本結晶学会誌 (ISSN:03694585)

巻号頁・発行日

vol.53, no.6, pp.416-418, 2011-12-31 (Released:2012-01-18)

参考文献数

6

被引用文献数

1 1

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In tobacco plants, elimination of Zn and Cd via the production of Ca-containing grains at the top of leaf hairs, called trichomes, is a potent detoxification mechanism. When tobacco plants were grown in a nutrient solution containing an amount of Cd and low Ca supplement, most of the grains were oblong-shaped and low-Cd-substituted calcite. When exposed to the same amount of Cd and high Ca supplement, grains were more abundant and diverse in compositions, and in total more Cd was eliminated. Most grains in the high Ca/Cd experiment were round-shaped and composed predominantly of Cd-substituted vaterite, a usually metastable calcium carbonate polymorph, and subordinate calcite.

著者

平山 令明

出版者

日本結晶学会

雑誌

日本結晶学会誌 (ISSN:03694585)

巻号頁・発行日

vol.30, no.5, pp.292, 1988-09-30 (Released:2010-09-30)

著者

高田 昌樹

出版者

日本結晶学会

雑誌

日本結晶学会誌 (ISSN:03694585)

巻号頁・発行日

vol.65, no.2, pp.145-146, 2023-05-31 (Released:2023-06-06)

著者

植草 秀裕

出版者

The Crystallographic Society of Japan

雑誌

日本結晶学会誌 (ISSN:03694585)

巻号頁・発行日

vol.38, no.5, pp.313-323, 1996-10-31 (Released:2010-09-30)

参考文献数

1

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Basic ideas and practical tips of the direct methods are presented for the beginners of crystal structure analysis.

著者

山本 隆文

出版者

日本結晶学会

雑誌

日本結晶学会誌 (ISSN:03694585)

巻号頁・発行日

vol.65, no.3, pp.165-166, 2023-08-31 (Released:2023-09-06)

参考文献数

7

著者

池田 陽一 梅本 好日古 藤田 全基

出版者

日本結晶学会

雑誌

日本結晶学会誌 (ISSN:03694585)

巻号頁・発行日

vol.65, no.3, pp.192-197, 2023-08-31 (Released:2023-09-06)

参考文献数

29

被引用文献数

1

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This report introduced the results of recent neutron scattering and X-ray absorption fine structure(EXAFS)experiments on a family of medium-entropy alloys(TrCoNi, Tr=Cr, Mn, and Fe). Neutron experiments revealed that the time-temperature-dependent short- and long-range structural transformation occurs in a medium-entropy alloy MnCoNi. Although a sign of short-range ordering was not clear in the EXAFS results, the mean-square relative displacement(MSRD)may catch the difference in local structures between medium-entropy alloys. The relatively large static MSRD of the MnCoNi sample can be interpreted as a sign of short-range tetragonal structural transformation, whereas the small value of the CrCoNi sample cannot be interpreted straightforwardly. A possible interpretation of the difference in MSRD was provided.

著者

市川 瑞彦

出版者

The Crystallographic Society of Japan

雑誌

日本結晶学会誌 (ISSN:03694585)

巻号頁・発行日

vol.40, no.1, pp.10-18, 1998-02-28 (Released:2010-09-30)

参考文献数

70

被引用文献数

1 1

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A review is given of the deuteration effect on the crystal structure, in particular on the hydrogen-bond system, and its relation to the phase transition. The correlation between hydrogen-bond parameters and some examples of peculiar phase diagrams between deuterium content and temperature are discussed in the context of the geometric isotope effect. Similarity and difference between the deuteration effect and the negative pressure effect are discussed in the case of KH2PO4 and squaric acid (H2C4O4) . It is pointed out that the hydrogen bond is not necessarily the softest part of the crystal as usually assumed, and pressure effect is responded by rotation of the PO4 or C4O4 group as well. The case of (NH4) 3H (SO4) 2 is discussed as an example where a surprising similarity between deuteration and positive pressure effect is seen in their phase diagrams.

著者

谷口 博基 伊藤 満 森分 博紀 単 躍進

出版者

日本結晶学会

雑誌

日本結晶学会誌 (ISSN:03694585)

巻号頁・発行日

vol.54, no.5, pp.276-281, 2012-10-31 (Released:2012-11-06)

参考文献数

16

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An Origin of ferroelectricity in Perovskite-type oxides is discussed from a viewpoint of relation between lattice dynamics and chemical bonding state, through comprehensive study of a Ca-substitution effect on the ferroelectricity in CdTiO3. The result indicates covalency of constituent elements plays an important role on the ferroelectricity in the perovskite-type oxides.

著者

松村 浩由 野末 佳伸 佐藤 和久 藤沢 浩訓

出版者

日本結晶学会

雑誌

日本結晶学会誌 (ISSN:03694585)

巻号頁・発行日

vol.50, no.4, pp.288-290, 2008-08-29 (Released:2010-09-30)

著者

大場 茂

出版者

日本結晶学会

雑誌

日本結晶学会誌 (ISSN:03694585)

巻号頁・発行日

vol.60, no.5-6, pp.270-271, 2018-12-15 (Released:2018-12-19)

参考文献数

12

著者

松村 浩由

出版者

The Crystallographic Society of Japan

雑誌

日本結晶学会誌 (ISSN:03694585)

巻号頁・発行日

vol.50, no.4, pp.245-253, 2008-08-29 (Released:2010-09-30)

参考文献数

27

被引用文献数

1

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Phosphoenolpyruvate carboxylase (PEPC) and ribulose 1, 5-bisphosphate carboxylase/oxygenase (Rubisco) play pivotal roles in CO2 fixation. Both of the enzymes are involved in photosynthetic efficiency of plants. Here, we report the crystal structures of PEPC and Rubisco; the inactivated Escherichia coli PEPC complexed with L-aspartate, the activated maize PEPC complexed with a sulfate, the Chlamydomonas Rubisco complexed with transition state analogue, and Galdieria Rubisco complexed with a sulfate. X-ray crystallographic analysis and site-directed mutagenesis studies revealed the allosteric regulation and the reaction mechanism of PEPC. The crystallographic studies on Rubisco provided detailed understanding of activity and regulation in Rubisco.

著者

古池 美彦

出版者

日本結晶学会

雑誌

日本結晶学会誌 (ISSN:03694585)

巻号頁・発行日

vol.65, no.2, pp.113-121, 2023-05-31 (Released:2023-06-06)

参考文献数

17

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The circadian clock, an internal timekeeping system created and utilized by organisms adapting to the Earth’s Rotation, is driven by the rhythmic chemical reaction cycles of biomolecules such as clock proteins and clock genes. The cyanobacterial clock system is composed of three clock proteins, KaiA, KaiB, and KaiC, which concert the circadian rhythms even in the test tube in the presence of adenosine-tri-phosphate(ATP). KaiC orchestrates the rhythm through an ATP hydrolysis(ATPase cycle)and auto-phosphorylation/dephosphorylation(Phospho-cycle). The N-terminal ring of functional KaiC hexamer determines the clock speed during the ATPase cycle, while another C-terminal ring changes phosphorylation status like time stamps during Phospho-cycle. Structural biology has been investigating the origin of the circadian rhythm in the KaiC double-ring structure for a quarter century. We conducted the comprehensive structural analyses on KaiC and finally identified structural factors that ensure the smooth and tight communication between those distant two catalytic sites, which is critical for the rhythmicity. We also revealed that the time information is propagated to the entire cell through the rearrangement of the KaiC double ring and the assembly/disassembly of KaiA and KaiB.

著者

井上 豪

出版者

日本結晶学会

雑誌

日本結晶学会誌 (ISSN:03694585)

巻号頁・発行日

vol.59, no.6, pp.316-317, 2017-12-31 (Released:2017-12-31)

著者

松村 浩由

出版者

日本結晶学会

雑誌

日本結晶学会誌 (ISSN:03694585)

巻号頁・発行日

vol.65, no.2, pp.88-95, 2023-05-31 (Released:2023-06-06)

参考文献数

36

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The increase in atmospheric carbon dioxide(CO2)concentration is likely to be related to global warming and climate change. Photosynthesis can convert atmospheric CO2 using light and water to produce many kinds of organic molecules. The lack of crystal structures of the enzymes involved in photosynthetic carbon assimilation has hindered the understanding of the detailed mechanisms. Crystallographic studies of the enzymes involved in photosynthetic carbon assimilation provide new insights into the molecular mechanisms.

著者

伊藤 傑

出版者

日本結晶学会

雑誌

日本結晶学会誌 (ISSN:03694585)

巻号頁・発行日

vol.65, no.2, pp.79-80, 2023-05-31 (Released:2023-06-06)

参考文献数

13