科学书四十七页笔记：科学20220902出版一周论文导读

科学书四十七页笔记：科学20220902出版一周论文导读https://www.science.org/doi/10.1126/science.abn0392▲ 链接：On the origins of fatigue strength in crystalline metallic materials晶体金属材料疲劳强度的来源▲ 作者：J. C. STINVILLE M. A. CHARPAGNE A. CERVELLON S. HEMERY F. WANG P. G. CALLAHAN V. VALLE T. M. POLLOCK

编译 | 冯维维

Science 2 Sep 2022 VOLUME 377 ISSUE 6610

《科学》2022年9月2日，第377卷，6610期

物理学Physics

On the origins of fatigue strength in crystalline metallic materials

晶体金属材料疲劳强度的来源

▲ 作者：J. C. STINVILLE M. A. CHARPAGNE A. CERVELLON S. HEMERY F. WANG P. G. CALLAHAN V. VALLE T. M. POLLOCK

▲ 链接：

https://www.science.org/doi/10.1126/science.abn0392

▲ 摘要：

循环变形的材料更容易因疲劳而断裂。然而，将疲劳强度与微观结构联系起来一直是一个挑战。作者利用纳米分辨率的数字图像相关技术观察了各种合金表面的滑移定位。

他们发现，在一个变形周期后，早期滑移局部化事件的振幅决定了疲劳强度。这一发现有助于为众所周知的疲劳规律提供物理基础，并为容易预测疲劳强度铺平了道路。

▲ Abstract：

Materials that are cyclically deformed become easier to break due to fatigue. However tying fatigue strength to microstructure has been challenging. Stinville et al. used nanometer-resolution digital image correlation to observe the slip localization on the surface of a wide range of alloys. They found that after one deformation cycle the amplitude of the early slip localization events determines fatigue strength. This observation helps to provide a physical basis for well-known fatigue laws and paves the way to easily predicting fatigue strength.

Magnetoelectric transfer of a domain pattern

磁畴模式的磁电转移

▲ 作者：EHSAN HASSANPOUR YANNIK ZEMP YUSUKE TOKUNAGAYASUJIRO TAGUCHI YOSHINORI TOKURA THOMAS LOTTERMOSER MANFRED FIEBIG AND MADS C. WEBER

▲ 链接：

https://www.science.org/doi/10.1126/science.abm3058

▲ 摘要：

多铁性材料通常具有磁化和电极化两个耦合序参量，这两个参量可以由外部场控制。作者研究了多铁性Dy0.7Tb0.3FeO3，它有一个额外的序参量，源于面内反铁磁序。研究人员创造了一个铁磁多畴模式，并施加了一个外部磁场，消除了现有的模式，但在系统的极化中创造了一个相同的形状，最大限度地减少了自由能。这个过程可以通过施加电场来逆转。

▲ Abstract：

Multiferroic materials are often characterized by two coupled order parameters magnetization and electrical polarization which can be controlled by external fields. Hassanpour et al. studied the multiferroic Dy0.7Tb0.3FeO3 which has an additional order parameter stemming from in-plane antiferromagnetic ordering. The researchers created a ferromagnetic multidomain pattern and applied an external magnetic field which erased the existing pattern but created one of the same shape in the system’s polarization minimizing the free energy. The process could be reversed by applying an electric field.

化学Chemistry

Late-stage diversification of indole skeletons through nitrogen atom insertion

吲哚中插入氮原子

▲ 作者：JULIA C. REISENBAUER ORI GREEN ALLEGRA FRANCHINO PATRICK FINKELSTEIN AND BILL MORANDI

▲ 链接：

https://www.science.org/doi/10.1126/science.add1383

▲ 摘要：

许多药物化合物含有由碳和氮组成的五元或六元环。因此，在药物开发研究过程中，这些相互转换的化学反应是非常有用的。

Reisenbauer等人提出了一种方法，将一个氮原子插入到硅基保护的吲哚的五元环中，从而根据它们一开始的取代模式将它们扩展为六元喹唑啉或喹唑啉化合物。这种化学反应依赖于用高价碘生成硝基，并与许多常见官能团相容。

▲ Abstract：

Numerous pharmaceutical compounds contain five- or six-membered rings composed of carbon and nitrogen. Chemical reactions that interconvert these motifs can therefore be very helpful during drug development research. Reisenbauer et al. present a method to insert a nitrogen atom into the five-membered rings of silyl-protected indoles thereby expanding them into six-membered quinazoline or quinoxaline compounds depending on their substitution pattern at the outset. The chemistry relies on nitrene generation using hypervalent iodine and is compatible with many common functional groups.

3D nanoprinting of semiconductor quantum dots by photoexcitation-induced chemical bonding

半导体量子点三维纳米打印

▲ 作者：SHAO-FENG LIU ZHENG-WEI HOU LINHAN LIN FU LI YAO ZHAO XIAO-ZE LI HAO ZHANG HONG-HUA FANG ZHENGCAO LI HONG-BO SUN etc.

▲ 链接：

https://www.science.org/doi/10.1126/science.abo5345

▲ 摘要：

纳米粒子的组装通常需要有针对性地选择配体，以便它们能够选择性地结合，就像与互补的DNA链结合一样。或者，它们可以通过光聚合在指定的位置连接在一起，从而在所需的位置连接配体。

然而，这一过程增加了制备纳米颗粒的复杂性，并受到配体附着保真度的限制。作者研究表明，光可以用于从硒化镉/硫化锌核壳量子点中解吸表面硫代配体。由此产生的俘获空穴通过剩余的表面配体驱动粒子之间的结合。

作者揭示了在超出衍射极限的分辨率和纳米晶体范围的任意三维结构的光打印。打印可以根据量子点的大小和/或带隙进行光学选择。

▲ Abstract：

Nanoparticle assembly often requires tailored selection of the ligands so that they can selectively bond as with complementary DNA strands. Alternately they can be linked together at specified locations using photopolymerization to connect ligands at desired places. However this process adds to the complexity of making the nanoparticles and is limited by the fidelity of the ligand attachment. Liu et al. show that light can be used to desorb surface thiolate ligands from cadmium selenide/zinc sulfide core shell quantum dots. The resulting trapped holes drive bonding between the particles through the remaining surface ligands. The authors reveal photoprinting of arbitrary three-dimensional architectures at a resolution beyond the diffraction limit and for a range of nanocrystals. Printing can be optically selected based on the size and/or bandgap of the quantum dots.

The human oxidation field

人类氧化场

▲ 作者：NORA ZANNONI PASCALE S. J. LAKEY YOUNGBO WONMANABU SHIRAIWA DONGHYUN RIM CHARLES J. WESCHLERNIJING WANG LISA ERNLE MENGZE LI JONATHAN WILLIAMS

▲ 链接：

https://www.science.org/doi/10.1126/science.abn0340

▲ 摘要：

羟基自由基（OH）是一种高度活性物质，是大多数污染物气体氧化的主要原因。在户外，OH自由基主要是由短波长的太阳光对臭氧的光解作用形成的，但这些光大部分被玻璃窗过滤掉了，那么室内的OH自由基环境是什么样的呢？

作者称，当人们暴露在气候可控的室内臭氧中时，会发现高浓度的OH自由基，这是与皮肤油脂角鲨烯反应的产物。他们的发现对室内空气质量有影响，最终对人类健康有影响。

▲ Abstract：

Hydroxyl radicals (OH) are highly reactive species that are responsible for the oxidation of most pollutant gases. Outdoors OH radicals are formed primarily by the photolysis of ozone by short-wavelength sunlight but that light is largely filtered out by glass windows so what is the indoor OH radical environment like? Zannoni et al. report that high concentrations of OH radicals were found when people were exposed to ozone in a climate-controlled chamber and were a product of a reaction with the skin oil squalene. Their finding has implications for indoor air quality and ultimately for human health.

气候学Climatology

A climate risk analysis of Earth’s forests in the 21st century

21世纪地球森林气候风险分析

▲ 作者：WILLIAM R. L. ANDEREGG CHAO WU XNEZHA ACIL NUNO CARVALHAIS THOMAS A. M. PUGH JON P. SADLER AND RUPERT SEIDL

▲ 链接：

https://www.science.org/doi/10.1126/science.abp9723

▲ 摘要：

气候变化通过极端高温、干旱和干扰对森林产生了负面影响。预测未来气候变化对森林的影响是具有挑战性的，因为每种方法都依赖于假设和不完整的数据。

Anderegg等人比较了提供风险不同方面信息的三种主要建模方法的结果:估计森林碳损失的全球机械植被模型;提供物种变化信息的气候包络模型;利用卫星图像进行森林受干扰损失的实证评估。

这些方法提供了补充信息，但也强调了南部北方、干燥的热带地区和中欧的森林面临的总体风险很高。

▲ Abstract：

Climate change is having negative effects on forests through extreme heat drought and disturbances. Predicting the impact of future climate change on forests is challenging because each approach relies on assumptions and incomplete data. Anderegg et al. compared results from three major modeling approaches that provide information on different facets of risk: a global mechanistic vegetation model which estimates forest carbon loss; a climate envelope model which provides information on species shifts; and empirical assessment of forest loss to disturbance using satellite imagery. These approaches provide complementary information but highlight the high overall risk to forests in the southern boreal dry tropics and central Europe.