The Roadmap of 2D Materials and Devices Toward Chips

Due to the constraints imposed by physical effects and performance degra certain limitations in sustaining the advancement of Moore’s law.Two-dimensional(2D)materials have emerged as highly promising candidates for the post-Moore era,offering significant potential in domains such as integrated circuits and next-generation computing.Here,in this review,the progress of 2D semiconductors in process engineering and various electronic applications are summarized.A careful introduction of material synthesis,transistor engineering focused on device configuration,dielectric engineering,contact engineering,and material integration are given first.Then 2D transistors for certain electronic applications including digital and analog circuits,heterogeneous integration chips,and sensing circuits are discussed.Moreover,several promising applications(artificial intelligence chips and quantum chips)based on specific mechanism devices are introduced.Finally,the challenges for 2D materials encountered in achieving circuit-level or system-level applications are analyzed,and potential development pathways or roadmaps are further speculated and outlooked.

Ultraconformable Integrated Wireless Charging Micro-Supercapacitor Skin

Conformable and wire-less charging energy storage devices play important roles in enabling the fast development of wearable,non-contact soft electronics.However,current wire-less charging power sources are still restricted by limited flexural angles and fragile connection of components,resulting in the failure expression of performance and constraining their fur-ther applications in health monitoring wearables and moveable artificial limbs.Herein,we present an ultracompatible skin-like integrated wireless charging micro-supercapacitor,which building blocks(including electrolyte,electrode and substrate)are all evaporated by liquid precursor.Owing to the infiltration and permeation of the liquid,each part of the integrated device attached firmly with each other,forming a compact and all-in-one configuration.In addition,benefitting from the controllable volume of electrode solution precursor,the electrode thickness is easily regulated varying from 11.7 to 112.5μm.This prepared thin IWC-MSC skin can fit well with curving human body,and could be wireless charged to store electricity into high capacitive micro-supercapacitors(11.39 F cm-3)of the integrated device.We believe this work will shed light on the construction of skin-attachable electronics and irregular sensing microrobots.

A new deformable cable for rock support in high stress tunnel:Steel pipe shrinkable energy-absorbing cable

High stress in surrounding rock will lead to serious problems,e.g.,rock burst in hard rock and large deformation in soft rock.The applied support system under high in-situ stress conditions should be able to carry high load and also accommodate large deformation without experiencing severe damage.In this paper,a specially designed energy-absorbing component for rock bolt and cable that can solve the above problems was proposed.The energy-absorbing component can provide support resistance by plastic deformation of the metal including constraint annulus and compression pipe.For practical engineering,two forms were proposed.One was installed in the surrounding rock by reaming,and the other was installed directly outside the surrounding rock.During the dilation of the surrounding rock,the relative displacement of constraint annulus and compression pipe occurs,resulting in deformation resistance.Deformation resistance is transmitted to the rock bolt or cable,providing support resistance.The lab test and numerical simulation showed that the energy-absorbing component can perfectly achieve the large deformation effect,the deformation amount is as high as 694 mm,and the bearing capacity is stable at 367 kN.The field application tests were carried out in the mining roadway of Xinjulong coal mine,and the results showed that the new type of cable can ensure itself not to break under the condition of large deformation of the surrounding rock.The energy-absorbing component has the superiorities of performing large constant resistance and controllable deformation to effectively control the unpredictable disasters such as large deformation in soft rock and rock burst in hard rock encountered in deep strata.

Timing effect of high temperature exposure on the plasticity of internode and plant architecture in maize

The occurrence of high temperature(HT)in crop production is becoming more frequent and unpredictable with global warming,severely threatening food security.The state of an organ’s growth and development is largely determined by the temperature conditions it is exposed to over time.Maize is the main cereal crop,and its stem growth and plant architecture are closely related to lodging resistance,and especially sensitive to temperature.However,systematic research on the timing effect of HT on the sequentially developing internode and stem is currently lacking.To identify the timing effect of HT on the morphology and plasticity of the stem in maize,two hybrids(Zhengdan 958(ZD958),Xianyu 335(XY335))characterized by distinct morphological traits in the stem were exposed to a 7-day HT treatment from the V6 to V17 stages(Vn presents the vegetative stage with n leaves fully expanded)in 2019-2020.The results demonstrated that exposure to HT during V6-V12 accelerated the rapid elongation of stems.For instance,HT occurring at V7 and V12 specifically promoted the lengths and weights of the 3rd-5th and 9th-11th internodes,respectively.Meanwhile,HT slowed the growth of internodes adjacent to the promoted internodes.Interestingly,compared with control,the plant height was significantly increased soon after HT treatment,but the promotion effect became narrower at the subsequent flowering stage,demonstrating a self-adjusting mechanism in the maize plant in response to HT.Importantly,HT altered the plant architectures,including a rising of the ear position and increase in the ear position coefficient.XY335 exhibited greater sensitivity in stem development than ZD958 under HT treatment.These findings improve our systematic understanding of the plasticity of internode and plant architecture in response to the timing of HT exposure.

Central Asia revealed as a key area in evolution of Eremurus (Asphodelaceae)

Eremurus was described at the beginning of the 19th century.However,due to limited sampling and the small number of gene markers to date,its phylogeny and evolution are largely unknown.In this study,we analyzed plastomes from 27 species belonging to 2 subgenera and 3 sections of Eremurus,which are found in Central Asia(its center of diversity)and China.We also analyzed nuclear DNA ITS of 33 species,encompassing all subgenera and sections of the genus in Central Asia,southwest Asia and China.Our findings revealed that the genus was monophyletic,although both subgenera Eremurus and Henningia were found to be paraphyletic.Both plastome and nrDNA-based phylogenetic trees had three clades that did not reflect the current taxonomy of the genus.Our biogeographical and time-calibrated trees suggest that Eremurus originated in the ancient Tethyan area in the second half of the Eocene.Diversification of Eremurus occurred from the early Oligocene to the late Miocene.Paratethys Sea retreat and several orogenetic events,such as the progressive uplift of the Qinghai-Tibet Plateau and surrounding mountain belts(Altai,Pamir,Tian Shan),caused serious topographic and climate(aridification)changes in Central Asia that may have triggered a split of clades and speciation.In this transformed Central Asia,speciation proceeded rapidly driven mainly by vicariance caused by numerous mountain chains and specialization to a variety of climatic,topographic and soil conditions that exist in this region.

连花清瘟药渣及发酵产物的生物活性研究

旨在研究连花清瘟药渣和发酵产物的生物学活性,探明自然发酵、优化发酵1(4MYL)和优化发酵2(Y4ML)三种发酵方式对药渣中营养成分的改变以及乙醇提取物和水提取物抑菌效果及抗病毒效果的差异。采用肉汤稀释法测定药渣发酵前后不同提取物对猪副嗜血杆菌(Haemophilus parasuis,HPS)、猪链球菌二型(Streptococcus suis type 2,SS2)、肠毒性大肠杆菌(Enterotoxigenic Escherichia coli,ETEC)3种致病菌菌株的最小抑菌浓度(MIC);以伪狂犬病病毒(Pseudorabies virus,PRV)、猪圆环病毒2型(porcine circovirus type 2,PCV2)、猪繁殖与呼吸综合征病毒(porcine reproductive and respiratory syndrome virus,PRRSV)分别感染非洲绿猴肾细胞(Vero)、非洲绿猴胚胎肾细胞(MARC-145)、猪肾细胞(PK-15),通过荧光显微镜观察细胞形态病变,同时结合实时荧光定量PCR技术进行病毒核酸检测和定量作为药物体外抗病毒效果的评价指标。结果表明,连花清瘟原药渣的乙醇和水提取物对HPS和SS2均表现出抑制作用,但对ETEC无抑制作用;对3种试验病毒均表现出抗病毒活性,但抗病毒活性存在一定区别。发酵后乙醇和水提取物增强了抗菌抗病毒活性,同时对ETEC表现出抑制作用。综上表明,连花清瘟药渣提取物具有不同程度的抗菌、抗病毒作用,能有效抑制猪养殖过程中HPS、SS2等常见的致病菌和病毒,发酵后能增强抗菌和抗病毒效果,具有开发成动物饲料或饲料添加剂的潜力。

干扰Mtmr 3基因对C2C12细胞增殖与分化的影响

旨在探究肌管相关蛋白3(myotubularin related protein 3,Mtmr 3)对C2C12细胞增殖与分化的调控作用及机制。本试验以小鼠成肌细胞系(C2C12)为试验材料,分别使用qRT-PCR和免疫荧光染色检测Mtmr 3基因在成肌细胞生长期与分化期的mRNA表达水平和分化第6天时的分布形态。合成Mtmr 3的小干扰RNA(small interfering RNA,siRNA),试验分为siRNA NC对照组和Mtmr 3 siRNA处理组(n=3),利用EdU、CCK-8、qRT-PCR、Western blot技术检测Mtmr 3 siRNA对成肌细胞增殖与分化的影响,并通过信号通路研究调控成肌细胞增殖与分化的机制。结果显示,Mtmr 3在生长期的mRNA水平表达量总体呈下降趋势,而在分化期的表达量呈逐渐上升趋势,Mtmr3免疫荧光染色呈肌管状。干扰Mtmr 3后,细胞内Mtmr 3基因的mRNA和蛋白表达水平均极显著地降低(P<0.01);在增殖试验中,转染细胞Mtmr 3 siRNA后,极显著地增加了EdU阳性细胞占总细胞的比率和细胞活力(P<0.01);干扰Mtmr 3表达后,Pcna和Cdk4的mRNA与蛋白表达水平极显著地升高(P<0.01),Ccnd基因的mRNA表达水平极显著地升高(P<0.01)。在分化试验中,转染Mtmr 3 siRNA后极显著抑制了分化标志基因Myhc蛋白的表达水平(P<0.01),极显著抑制细胞分化第4和6天Mtmr 3、Myog和Myhc基因在mRNA的表达水平(P<0.01)。在增殖期和分化期干扰Mtmr 3表达后,Mtor和P70s6k的磷酸化蛋白表达水平分别极显著升高和极显著降低(P<0.01)。CCK-8的结果表明,与对照组相比,Mtmr 3 siRNA能够抵消部分Mtor通路特异性抑制剂Rapamycin(Rapa)的抑制作用,促进成肌细胞增殖(P<0.01);在细胞分化时加入Rapa处理成肌细胞,细胞内Mtor、P 70s6k、Myog和Myhc基因的mRNA表达水平均显著降低(P<0.05)。综上所述,Mtmr 3在成肌细胞生长期的表达量呈下降趋势,而在分化期的表达量呈逐渐上升趋势,Mtmr3免疫荧光染色呈肌管状。干扰Mtmr 3基因表达,通过激活Mtor通路促进成肌细胞增殖,通过失活Mtor通路抑制成肌细胞分化。

Diluent decomposition-assisted formation of Li F-rich solid-electrolyte interfaces enables high-energy Li-metal batteries

Passivation by the inorganic-rich solid electrolyte interphase(SEI),especially the LiF-rich SEI,is highly desirable to guarantee the durable lifespan of Li metal batteries(LMBs).Here,we report a diluent with the capability to facilitate the formation of LiF-rich SEI while avoiding the excess consumption of Li salts.Dissimilar to most of reported inert diluents,heptafluoro-l-methoxypropane(HM) is firstly demonstrated to cooperate with the decomposition of anions to generate LiF-rich SEI via releasing Fcontaining species near Li surface.The designed electrolyte consisting of 1.8 M LiFSI in the mixture of1,2-dimethoxyethane(DME)/HM(2:1 by vol.) achieves excellent compatibility with both Li metal anodes(Coulombic efficiency~99.8%) and high-voltage cathodes(4.4 V LiNi_(0.8)Mn_(0.1)Co_(0.1)O_(2)(NMC811) and 4.5 V LiCoO_(2)(LCO) vs Li^(+)/Li).The 4.4 V Li(20μm)‖NMC811(2.5 mA h cm^(-2)) and 4.5 V Li(20μm)‖LCO(2.5 mA h cm^(-2)) cells achieve capacity retentions of 80% over 560 cycles and 80% over 505 cycles,respectively.Meanwhile,the anode-free pouch cell delivers an energy density of~293 W h kg^(-1)initially and retains 70% of capacity after 100 deep cycles.This work highlights the critical impact of diluent on the SEI formation,and opens up a new direction for designing desirable interfacial chemistries to enable high-performance LMBs.

Origins and evolution of plant diversity in the Hengduan Mountains, China

1.Introduction The Hengduan Mountains region(HDM)in southwest China,one of the earth's 34 biodiversity hotspots,is characterized by its unique geology,dramatic topography,a climate where snow and below freezing temperatures can occur on any day of the year,by its location at elevations averaging between(1400e)2000 and4500(e5300)meters above sea level(m a.s.l.),and by one of

A review:Photonics devices,architectures,and algorithms for optical neural computing

The explosive growth of data and information has motivated various emerging non-von Neumann computational approaches in the More-than-Moore era.Photonics neuromorphic computing has attracted lots of attention due to the fascinating advantages such as high speed,wide bandwidth,and massive parallelism.Here,we offer a review on the optical neural computing in our research groups at the device and system levels.The photonics neuron and photonics synapse plasticity are presented.In addition,we introduce several optical neural computing architectures and algorithms including photonic spiking neural network,photonic convolutional neural network,photonic matrix computation,photonic reservoir computing,and photonic reinforcement learning.Finally,we summarize the major challenges faced by photonic neuromorphic computing,and propose promising solutions and perspectives.

Plant diversity in Yunnan:Current status and future directions

Yunnan,located in southwestern China,harbors more than 19,000 higher plants,which represents the highest plant diversity in the country.However,plant diversity in Yunnan faces enormous threats today,including habitat destruction and fragmentation,environmental pollution,and over-exploitation of natural resources.Despite recent efforts to protect biodiversity,there are still thousands of threatened species,some of which have become extinct.We analyzed available data to gain a greater understanding of plant diversity and the status of plant conservation in Yunnan.We found that southern,southeastern,and northwestern Yunnan are hotspots of total species,endemic species,specimens,new species and threatened species,whereas southeastern Yunnan is a hotspot for plant species with extremely small populations.Moreover,we found that there are still conservation gaps and poorly protected areas in central,eastern,and northeastern Yunnan.We conclude that conservation of plant diversity in Yunnan requires modern field investigation,systematic research,the development of comprehensive databases,and government support.We recommend that conservationists pay more attention to building and improving functional protection systems and popularizing science.

Structural evolution of Pt‐based oxygen reduction reaction electrocatalysts

The commercialization of proton exchange membrane fuel cells(PEMFCs)could provide a cleaner energy society in the near future.However,the sluggish reaction kinetics and harsh conditions of the oxygen reduction reaction affect the durability and cost of PEMFCs.Most previous reports on Pt-based electrocatalyst designs have focused more on improving their activity;however,with the commercialization of PEMFCs,durability has received increasing attention.In-depth insight into the structural evolution of Pt-based electrocatalysts throughout their lifecycle can contribute to further optimization of their activity and durability.The development of in situ electron microscopy and other in situ techniques has promoted the elucidation of the evolution mechanism.This mini review highlights recent advances in the structural evolution of Pt-based electrocatalysts.The mechanisms are adequately discussed,and some methods to inhibit or exploit the structural evolution of the catalysts are also briefly reviewed.

Source Contributions to PM2.5 under Unfavorable Weather Conditions in Guangzhou City,China

Historical haze episodes（2013–16） in Guangzhou were examined and classified according to synoptic weather systems.Four types of weather systems were found to be unfavorable, among which ＂foreside of a cold front＂（FC） and ＂sea high pressure＂（SP） were the most frequent（〉 75% of the total）. Targeted case studies were conducted based on an FC-affected event and an SP-affected event with the aim of understanding the characteristics of the contributions of source regions to fine particulate matter（PM（2.5）） in Guangzhou. Four kinds of contributions—namely, emissions outside Guangdong Province（super-region）, emissions from the Pearl River Delta region（PRD region）, emissions from Guangzhou–Foshan–Shenzhen（GFS region）, and emissions from Guangzhou（local）—were investigated using the Weather Research and Forecasting–Community Multiscale Air Quality model. The results showed that the source region contribution differed with different weather systems. SP was a stagnant weather condition, and the source region contribution ratio showed that the local region was a major contributor（37%）, while the PRD region, GFS region and the super-region only contributed 8%, 2.8% and 7%, respectively, to PM（2.5） concentrations. By contrast, FC favored regional transport. The super-region became noticeable,contributing 34.8%, while the local region decreased to 12%. A simple method was proposed to quantify the relative impact of meteorology and emissions. Meteorology had a 35% impact, compared with an impact of-18% for emissions, when comparing the FC-affected event with that of the SP. The results from this study can provide guidance to policymakers for the implementation of effective control strategies.

Prunus sunhangii: A new species of Prunus from central China

A new species of Rosaceae from Central China, Prunus sunhangii D. G. Zhang & T. Deng, sp. nov., is described and illustrated. The new species is placed in Prunus subgenus Cerasus by flower and fruit characteristics. It is most similar to Prunus cerasoides, but differs by having longitudinally 2-lobed apical petals, an acuminate leaf apex, 17—25 stamens, white petals, dark black drupes, brown hypanthium, and different phenology. The phylogenetic placement of this species was assessed based on morphological and molecular data. Molecular analysis(cp DNA + ITS) corroborated its placement in subgenus Cerasus,specifically Prunus section Serrula.

A High-Throughput, Multi-Index Isothermal Amplification Platform for Rapid Detection of 19 Types of Common Respiratory Viruses Including SARS-CoV-2

快速、准确地诊断以及及时对感染严重急性呼吸综合征冠状病毒2(SARS-CoV-2)的患者进行隔离被认为是抗击新冠病毒肺炎(COVID-19)大流行的最有效的措施。本文介绍了一款高通量、多指标的等温扩增检测平台(RTisochip^TM-W),该平台使用离心式微流控芯片,在90min内即可完成一次运行,从16个样本中检测出包括SARS-CoV-2在内的19种常见呼吸道病毒。通过RTisochip^TM-W系统检测的所有病毒的检出限均等于或小于50拷贝·μL^-1,与常规逆转录聚合酶链反应(RT-PCR)灵敏度相当。该系统具有重复性好、鲁棒性强和特异性高的优点。最后,使用RTisochip^TM-W系统对201例临床前样本、14例COVID-19阳性临床样本、25例临床确诊样本以及614例来自呼吸道感染或疑似感染的患者的临床样本进行了测试。测试结果与临床诊断结果吻合良好,也反映出呼吸道传染病的流行特征。在对SARS-CoV-2的诊断上,RTisochip^TM-W系统与参考试剂盒的一致性达到98.15%。基于大量的测试结果,我们相信RTisochip^TM-W系统是一款抗击COV ID-19大流行的强有力工具。

Bore-center annular shaped charges with different liner materials penetrating into steel targets

The bore-center annular shaped charge(BCASC)is a new type of shaped charge which can generate a larger-diameter hole in steel targets than classical shaped charges.In this paper,the influence of three liner materials,i.e.molybdenum,nickel and copper,on BCASC formation and penetrating into steel targets was investigated by experiment and numerical simulation.The simulation results were well consistent with the experimental results.This study showed that,at 0.50D standoff distance,the axial velocity of the molybdenum projectile was lower than that of the nickel and copper projectiles.The nickel and copper projectiles had almost the same head velocity.The absolute values of the radial velocity of the molybdenum projectile head was lower than that of the nickel and copper projectiles.However,at 0.75D standoff distance,the absolute values of the radial velocity of the molybdenum projectile head became much greater than that of the nickel and copper projectile heads.The projectile formed by BCASC with the molybdenum liner had the highest penetration depth of 61.5 mm,which was 10.0%and 21.3%higher than that generated by the copper and nickel projectiles.

Studies on the key parameters in segmental lining design

The uniform ring model and the shell-spring model for segmental lining design are reviewed in thisarticle. The former is the most promising means to reflect the real behavior of segmental lining, while thelatter is the most popular means in practice due to its simplicity. To understand the relationship and thedifference between these two models, both of them are applied to the engineering practice of FuzhouMetro Line I, where the key parameters used in both models are described and compared. The effectiveratio of bending rigidity h reflecting the relative stiffness between segmental lining and surroundingground and the transfer ratio of bending moment x reflecting the relative stiffness between segment andjoint, which are two key parameters used in the uniform ring model, are especially emphasized. Thereasonable values for these two key parameters are calibrated by comparing the bending momentscalculated from both two models. Through case studies, it is concluded that the effective ratio of bendingrigidity h increases significantly with good soil properties, increases slightly with increasing overburden,and decreases slightly with increasing water head. Meanwhile, the transfer ratio of bending moment xseems to only relate to the properties of segmental lining itself and has a minor relation with the groundconditions. These results could facilitate the design practice for Fuzhou Metro Line I, and could alsoprovide some references to other projects with respect to similar scenarios.

Phylogenomics of Allium section Cepa(Amaryllidaceae)provides new insights on domestication of onion

Allium sect.Cepa(Amaryllidaceae)comprises economically important plants,yet resolving the phylogenetic relationships within the section has been difficult as nuclear and chloroplast-based phylogenetic trees have been incongruent.Until now,phylogenetic studies of the section have been based on a few genes.In this study,we sequenced the complete chloroplast genome(plastomes)of four central Asian species of sect.Cepa:Allium oschaninii,A.praemixtum,A.pskemense and A.galanthum.Their chloroplast(cp)genomes included 114 unique genes of which 80 coded proteins.Seven protein-coding genes were highly variable and therefore promising for future phylogenetic and phylogeographic studies.Our plastome-based phylogenetic tree of Allium sect.Cepa revealed two separate clades:one comprising the central Asian species A.oschaninii,A.praemixtum,and A.pskemense,and another comprising A.galanthum,A.altaicum,and two cultivated species,A.cepa and A.fistulosum.These findings contradict previously reported phylogenies that relied on ITS and morphology.Possible explanations for this discrepancy are related to interspecific hybridization of species ancestral to A.galanthum and A.cepa followed by chloroplast capture;however,this is impossible to prove without additional data.Our results suggest that the central Asian Allium species did not play a role in the domestication of the common onion.Among the chloroplast genes,rpoC2 was identified as a gene of choice in further phylogeographical studies of the genus Allium.

Oreocharis xieyongii,an unusual new species of Gesneriaceae from western Hunan,China

A new species,Oreocharis xieyongii T.Deng,D.G.Zhang&H.Sun,from Hunan Province,central China,is described.The combination of purple zygomorphic corolla with longer adaxial lobes and exserted stamens defines the species and discriminates it from all other current Oreocharis species.Morphological traits of the new species were compared to those of two similar species,Oreocharis xiangguiensis and 0.rubrostriata.Phylogenetic analysis indicates that the new species is nested within the Oreocharis.Although only half of Oreocharis species were included in our study,evolutionary character analysis indicates that the ancestral states of the genus are likely the purple corolla,longer abaxial lip and inserted stamens.The longer adaxial lip is perhaps an apomorphy and only present in O.xieyongii and O.rubrostriata.Both morphological and molecular evidence suggest that O.xieyongii is a taxon new to science.

In-situ monitoring of dynamic behavior of catalyst materials and reaction intermediates in semiconductor catalytic processes

Semiconductor photocatalysis, as a key part of solar energy utilization, has far-reaching implications for industrial, agricultural, and commercial development. Lack of understanding of the catalyst evolution and the reaction mechanism is a critical obstacle for designing efficient and stable photocatalysts. This review summarizes the recent progress of in-situ exploring the dynamic behavior of catalyst materials and reaction intermediates. Semiconductor photocatalytic processes and two major classes of in-situ techniques that include microscopic imaging and spectroscopic characterization are presented. Finally, problems and challenges in in-situ characterization are proposed, geared toward developing more advanced in-situ techniques and monitoring more accurate and realistic reaction processes, to guide designing advanced photocatalysts.