体系的で制御可能な負,ゼロ,陽の熱膨張を立方Zr{1-x}Sn{-x}Mo2O8で表した
Sarah E Tallentire1, Felicity Child, Ian Fall
1Department of Chemistry, Durham University, Science Laboratories, South Road, Durham DH1 3LE, United Kingdom.
Journal of the American Chemical Society
|July 31, 2013
まとめ
研究者は,調節可能な熱膨張を持つZr1-xSnxMo2O8材料を開発しました. この単相システムは,複合材料とは異なり,高度なアプリケーションの制御された収縮と膨張を可能にします.
科学分野:
- マテリアルサイエンス 材料科学
- 固体化学 固体化学
- クリスタルグラフィーです.
背景:
- 従来の材料は,限定的または固定された熱膨張特性を持つことが多い.
- 複合材料は,通常,調整可能な熱膨張を達成するために使用され,これはインターフェースの問題につながる可能性があります.
- 熱膨張の理解と制御は,航空宇宙,電子,精密工学のアプリケーションに不可欠です.
研究 の 目的:
- 新しい素材ファミリーを合成し,特徴づけるために,Zr1-xSnxMo2O8 (0 < x < 1) を用いた.
- 単相材料内の同位体熱膨張係数を体系的に制御することを実証する.
- これらの材料,特に"立方体"SnMo2O8.8の構造特性と相変遷を調査する.
主な方法:
- 組成が異なるZr1-xSnxMo2O8素材の固体合成.
- X線 difraktion (XRD) と熱膨張測定を用いた特徴付け.
- 段階移行を検知するために,時間および温度に依存する difraktion 研究.
主要な成果:
- Zr1-xSnxMo2O8の一連の材料が,調節可能な同otropic熱膨張係数で成功して合成されました.
- -7.9(2) × 10−6から+5.9(2) × 10−6 K−1 (12−500 K) までの線形熱膨張係数 (αl) は,単一フェーズで達成されました.
- この研究では",立方体"のSnMo2O8の詳細な構造と熱膨張行動が報告されており,秩序ある状態と無秩序な状態の間の相移行も含まれています.
結論:
- Zr1-xSnxMo2O8システムは,熱膨張を正確に制御するためのユニークな単相プラットフォームを提供します.
- これらの材料は,調節可能な拡張を必要とするアプリケーションの複合材料に有効な代替品を提供します.
- この発見は,移行金属酸化物における構造-特性関係とその熱的振る舞いの基本的な理解に貢献します.
さらに関連する動画
関連する概念動画
Thermal expansion and Thermal stress: Problem Solving
San Francisco's Golden Gate Bridge is exposed to temperatures ranging from -15 °C to 40 °C. At its coldest, the main span of the bridge is 1275 m long. Assuming that the bridge is made entirely of steel, what is the change in its length between these temperatures?
To solve the problem, first, identify the known and unknown quantities. The initial length (L) of the bridge is 1275 m, the coefficient of linear expansion (α) for steel is 12 x 10-6/°C, and the change in temperature (ΔT) is 55 °C.
To solve the problem, first, identify the known and unknown quantities. The initial length (L) of the bridge is 1275 m, the coefficient of linear expansion (α) for steel is 12 x 10-6/°C, and the change in temperature (ΔT) is 55 °C.
Zeroth Law of Thermodynamics
Experimentally, if object A is in equilibrium with object B, and object B is in equilibrium with object C, then object A is in equilibrium with object C. That statement of transitivity is called the "zeroth law of thermodynamics." For example, a cold metal block and a hot metal block are both placed on a metal plate at room temperature. Eventually, the cold block and the plate will be in thermal equilibrium. In addition, the hot block and the plate will be in thermal equilibrium. By the zeroth...
Thermal Strain
Thermal strain is a concept that arises when we consider how temperature changes affect structures. Unlike the conventional assumption that structures remain constant under load, real-world scenarios often involve temperature fluctuations that can significantly impact these structures. Consider a homogeneous rod with a uniform cross-section resting freely on a flat horizontal surface. If the rod's temperature increases, the rod elongates. This elongation is proportional to the temperature...
Thermal Expansion
The expansion of alcohol in a thermometer is one of many commonly encountered examples of thermal expansion, which is the change in size or volume of a given system as its temperature changes. The most visible example is the expansion of hot air. When air is heated, it expands and becomes less dense than the surrounding air, which then exerts an upward force on the hot air to, for example, make steam and smoke rise, and hot air balloons float. The same behavior happens in all liquids and gases,...
Third Law of Thermodynamics
A pure, perfectly crystalline solid possessing no kinetic energy (that is, at a temperature of absolute zero, 0 K) may be described by a single microstate, as its purity, perfect crystallinity,and complete lack of motion means there is but one possible location for each identical atom or molecule comprising the crystal (W = 1). According to the Boltzmann equation, the entropy of this system is zero.
Temperature Dependent Deformation
In a nonhomogeneous rod made up of steel and brass, restrained at both ends and subjected to a temperature change, several steps are involved in calculating the stress and compressive load. Due to the problem's static indeterminacy, one end support is disconnected, allowing the rod to experience the temperature change freely. Next, an unknown force is applied at the free end, triggering deformations in the rod's steel and brass portions. These deformations are then calculated and added together...


