Phase characterisation of metalenses

Metalenses have emerged as a new optical element or system in recent years, showing superior performance and abundant applications. However, the phase distribut...     

Repetitive Sequence Barcode Probe for Karyotype Analysis in Tripidium arundinaceum

The barcode probe is a convenient and efficient tool for molecular cytogenetics. Tripidium arundinaceum, as a polyploid wild allied genus of Saccharum, is a useful genetic resource that confers biotic and abiotic stress resistance for sugarcane breeding. Unfortunately, the basic cytogenetic information is still unclear due to the complex genome. We constructed the Cot-20 library for screening moderately and highly repetitive sequences from T. arundinaceum, and the chromosomal distribution of these repetitive sequences was explored. We used the barcode of repetitive sequence probes to distinguish the ten chromosome types of T. arundinaceum by fluorescence in situ hybridization (FISH) with Ea-0907, Ea-0098, and 45S rDNA. Furthermore, the distinction among homology chromosomes based on repetitive sequences was constructed in T. arundinaceum by the repeated FISH using the barcode probes including Ea-0663, Ea-0267, EaCent, 5S rDNA, Ea-0265, Ea-0070, and 45S rDNA. We combined these probes to distinguish 37 different chromosome types, suggesting that the repetitive sequences may have different distributions on homologous chromosomes of T. arundinaceum. In summary, this method provide a basis for the development of similar applications for cytogenetic analysis in other species.     

用线性预测差分编码进行数据压缩的理论与效果

本文阐述了线性预测差分编码法(LPCM)应用于模拟地震信号数据压缩的理论和方法通过蒙特卡洛法(Monte-Caromethod)在DJS-130机上对容量为256的样本作了实验,取得了较好的效果经压缩后的信息可使每抽样编码字长降低2比特以上,使量化信噪比增益等于13db以上对影响压缩效果的各种因素进行了分析,发现在给定条件下最佳预测阶数为6,且增大直流电平可以明显地改善压缩效果,LPCM对信号压缩时具有自适应性提出了硬件实现的设想。     

Development of a Highly Selective,Sensitive, and Fast Response Upconversion Luminescent Platform for Hydrogen Sulfide Detection

Hydrogen sulfide (H₂S) has been recognized as one of most important gaseous signaling molecules mediated by a variety of physiological and pathological processes. Yet, its functions remain largely elusive due to the lack of potent monitoring methods. Hereby this issue is addressed with a powerful new platform—dye‐assembled upconversion nanoparticles (UCNPs). A series of chromophores with different absorption bands and fast responses towards H₂S is combined with UCNPs and results in a library of H₂S sensors with responsive emission signals ranging from the visible to the near‐infrared (NIR) region. These nanoprobes demonstrate highly selective and rapid responses to H₂S in vitro and in cells. Furthermore, H₂S levels in blood can be detected using the developed nanoprobes. Hence the reported H₂S sensing platform can serve as a powerful diagnostic tool to research H₂S functions and to investigate H₂S‐related diseases.     

Pinning Cluster Synchronization for Delayed Dynamical Networks via Kronecker Product

In this paper, the cluster synchronization is investigated for a class of dynamical networks composed of N delayed Lur’e systems by using pinning control strategy. Through combining the Kronecker product with reciprocal convex technique, some sufficient conditions are derived to ensure the cluster synchronization for the addressed networks such that the designed linear feedback controller can be employed to every cluster. Especially, the inner coupling matrices are not restricted to be diagonal and the problems of the controller design can be converted into solving a series of linear matrix inequalities (LMIs), which extend the application area and reduce the computational complexity. Finally, three numerical examples are provided to demonstrate the effectiveness of the derived results.     

InP中皮秒快速现象

利用测量瞬态反射谱的方法，探索了掺硫、铁、锌以及非掺杂的ＩｎＰ中载流子寿命，观察到非掺杂ＩｎＰ中载流子寿命最长约６０ｐｓ，掺锌ＩｎＰ中载流子寿命３８ｐｓ居中，掺硫和掺铁的寿命最短约１ｐｓ掺硫、铁和锌的ＩｎＰ中载流子寿命下降，是由于掺杂引入了复合中心，这一结果已被喇曼光谱所证实。     

Embedding RhPx in N,P Co‐Doped Carbon Nanoshells Through Synergetic Phosphorization and Pyrolysis for Efficient Hydrogen Evolution

Rational design and controllable synthesis of well‐defined nanostructures with high stability and Pt‐like activity for hydrogen evolution reaction (HER) are critical for renewable energy conversion. Herein, a unique pyrolysis strategy is demonstrated for the synthesis of RhP_x nanoparticles (NPs) in N, P co‐doped thin carbon nanoshells (RhP_x@NPC nanoshells) that display high electrocatalytic activity and stability over a wide pH range. This strategy involves simultaneous phosphorization and pyrolysis processes that can produce highly‐dispersed RhP_x NPs within N, P co‐doped carbon nanoshells and at the same time induce thinning of carbon nanoshells from inside out. The resulting RhP_x@NPC nanoshells not only possess Pt‐like activity for HER with low overpotentials to achieve 10 mA cm^?2 (22 mV in 0.5 m H₂SO₄, 69 mV in 1.0 m KOH, and 38 mV in 1.0 m phosphate buffered saline (PBS)) but also provide long‐term durability in a wide pH range. The remarkable HER performance of RhP_x@NPC nanoshells is ascribed to the high surface area, abundant mesoporosity, strong catalyst–support interaction, ultrathin carbon encapsulation, and N, P co‐doping. This work provides an effective strategy for designing heterostructured electrocatalysts with high catalytic activity and stability desired for reactions that may occur under harsh conditions.     

一种空空导弹发射装置故障诊断仪设计

导弹发射装置是目前我国某型战斗机所装备的主要作战武器之一,它的性能直接影响到战斗机的战斗能力,由于目前缺乏有效的故障诊断系统和仪器对导弹发射装置进行测试,所以设计了一种空空导弹发射装置故障诊断仪器;该仪器以工业控制计算机为核心,采用数据库编程技术编程,综合运用标准接口及总线技术、故障诊断技术,FIFO技术,有效地提高了仪器的通用性、可靠性;研究结果表明,该仪器能够对某型空空导弹发射装置的各种故障进行快速准确的诊断,提高部队的保障能力,具有很好的推广应用前景和重大的经济效益.     

Strengthening and toughening mechanism of a Cu-bearing high-strength low-alloy steel with refined tempered martensite/bainite (M/B) matrix and minor inter-critical ferrite

The microstructure–mechanical property relationship of a Cu-bearing low-carbon high-strength low-alloy steel, subjected to a novel multistage heat treatment inc...     

光子晶体光纤飞秒激光技术研究进展

光子晶体光纤自诞生至今的十几年来得到了快速发展,不同结构和各具特色的光子晶体光纤层出不穷。以应用于飞秒激光技术的各种光子晶体光纤为主线,介绍了目前基于光子晶体光纤飞秒激光技术的实验研究进展,尤其是高功率、高能量飞秒激光系统的研究现状和发展方向。