Thermoacoustic imaging:From single-element scanning to portable and array-based imaging

The microwave-induced thermoacoustic imaging(TAI)technology has both the advantages of high contrast of microwave imaging and high resolution of ultrasound imaging(UI),so it has carried out exploratory application research in various areas,such as the early detection of breast tumors and cerebrovascular diseases.However,the microwave generator used in the traditional TAI technology is huge and expensive,and the temporal resolution is also too low due to the single-element scanning mechanism.Thus,it is difficult to meet the needs of clinical applications.In this paper,the iterative process and the analysis of related application scenarios from single-element scanning to portable and array-based TAI,such as the miniaturized microwave generator,handheld antenna,multi-channel data acquisition,and UI/TAIdual-modality imaging,are reviewed,and the future trends of this technology are discussed.This review helps researchers in the field of TAI learn the technological development process and future trends.It also deepens clinicians’understanding of TAI so as to put forward more application requirements.

Single-element amorphous palladium nanoparticles formed via phase separation

Physically vitrifying amorphous single-element metal requires ultrahigh cooling rates,which are still unachievable for most of the closest-packed metals.Here,we report a facile chemical synthetic strategy for single-element amorphous palladium nanoparticles with a purity of 99.35 at.%±0.23 at.%from palladium–silicon liquid droplets.In-situ transmission electron microscopy directly detected the solidification of palladium and the separation of silicon.Further hydrogen absorption experiment showed that the amorphous palladium expanded little upon hydrogen uptake,exhibiting a great potential application for hydrogen separation.Our results provide insight into the formation of amorphous metal at nanoscale.

Single-element amorphous metals

To unveil the nature of amorphous states,single-element amorphous metals have been the perfect research subject due to the simplest composition.However,the extreme crystal nucleation and growth rate in single-element metal make the synthesis of single-element amorphous metals seemingly impossible in the past.Fortunately,benefited by several delicate synthetic strategies developed recently,the single-element amorphous metals have been successfully demonstrated.This review aims to provide a systematic overview of the synthesis of single-element amorphous metals covering the challenges in physics and recent achieve-ments.In addition,current understanding of the atomic and electronic structures of single-element amorphous metal has also been included.Finally,the challenges that worth further investigation are discussed.By identifying the potential avenues for further exploration,this review aims to contribute valuable insights that will propel the cognition of single-element amorphous metals.

Forecast of steel cord demand after the financial crisis

To analyze the production and marketing of China automobile in Year 2009,and also the development of China automobile and steel cord in those 11 years.The single-element regression mathematics model was set up to analyze the steel cord demand and automobile production.It predicted that automobile production would up to 15 170 000,16 690 000 and 18 360 000 respectively from 2010 to 2012,with the confidence as of 95%,the steel cord consumption in those three years will be 1 180 000 - 1 370 000 t, 1 320 000 - 1 520 000 t and 1 470 000 - 1 680 000 t.As to the policy of China stimulation,The role of Chinese tire has converted from the export-oriented to domestic consumer smoothly,so the effect of US special protectionist tariffs is limited in China.

Present advances and perspectives of broadband photo-detectors based on emerging 2D-Xenes beyond graphene

As an excellent optical device,photodetectors have many important applications,such as communication technology,display technology,scientific measurement,fire monitoring,aerospace and biomedical research,and ifs of great significance in the research of nanotechnology and optoelectronics.Graphene,as the first two-dimensional(2D)single-element nanomaterial,has the advantages of high carrier mobility,high strength,high light transmittance and excellent thermal conductivity,and ifs widely used in various nano-optical devices.The great success of graphene has led scientists to extensive research on other 2D single-element nanomaterials.Recently,a group of novel 2D single-element nanomaterials have attracted a lot of attention from scientists because of its excellent physical,chemical,electronic,mechanical and optical properties.Furthermore,it has opened a new door for the realization of new and efficient photodetectors.The group of 2D single-element nanomaterials are called 2D-Xenes and used to make high-performance photodetectors.Currently,there are few studies on photodetectors based on 2D-Xenes,but some 2D-Xenes have been applied to photodetectors and reported.Some of these have excellent photodetection performance,such as high photoresponsivity(R),broad spectral response range,fast photoresponse speed and high specific detectivity(D).Based on the novel 2D-Xenes,this review explores the types and preparation methods of 2D-Xenes,and the working mechanisms of 2D-Xenes photodetectors.Finally,the challenges and development trends of 2D-Xenes in the future are discussed.The research of 2D-Xenes is of great significance for the development of high-performance photodetectors in the future,and is expected to be widely used in other nanoelectronics and optical devices.