3D‑Printed Carbon‑Based Conformal Electromagnetic Interference Shielding Module for Integrated Electronics

Electromagnetic interference shielding(EMI SE)modules are the core com-ponent of modern electronics.However,the tra-ditional metal-based SE modules always take up indispensable three-dimensional space inside electronics,posing a major obstacle to the integra-tion of electronics.The innovation of integrating 3D-printed conformal shielding(c-SE)modules with packaging materials onto core electronics offers infinite possibilities to satisfy ideal SE func-tion without occupying additional space.Herein,the 3D printable carbon-based inks with various proportions of graphene and carbon nanotube nanoparticles are well-formulated by manipulating their rheological peculiarity.Accordingly,the free-constructed architectures with arbitrarily-customized structure and multifunctionality are created via 3D printing.In particular,the SE performance of 3D-printed frame is up to 61.4 dB,simultaneously accompanied with an ultralight architecture of 0.076 g cm^(-3) and a superhigh specific shielding of 802.4 dB cm3 g^(-1).Moreover,as a proof-of-concept,the 3D-printed c-SE module is in situ integrated into core electronics,successfully replacing the traditional metal-based module to afford multiple functions for electromagnetic compatibility and thermal dissipa-tion.Thus,this scientific innovation completely makes up the blank for assembling carbon-based c-SE modules and sheds a brilliant light on developing the next generation of high-performance shielding materials with arbitrarily-customized structure for integrated electronics.

Superconductivity of Lanthanum Superhydride Investigated Using the Standard Four-Probe Configuration under High Pressures

Recently,the theoretically predicted lanthanum superhydride,LaH 10±δ,with a clathrate-like structure was successfully synthesized and found to exhibit a record high superconducting transition temperature T c≈250 K at∼170 GPa,opening a new route for room-temperature superconductivity.However,since in situ experiments at megabar pressures are very challenging,few groups have reported the∼250 K superconducting transition in LaH 10±δ.Here,we establish a simpler sample-loading procedure that allows a relatively large sample size for synthesis and a standard four-probe configuration for resistance measurements.Following this procedure,we successfully synthesized LaH 10±δwith dimensions up to 10×20μm^2 by laser heating a thin La flake and ammonia borane at∼1700 K in a symmetric diamond anvil cell under the pressure of 165 GPa.The superconducting transition at T c≈250 K was confirmed through resistance measurements under various magnetic fields.Our method will facilitate explorations of near-room-temperature superconductors among metal superhydrides.

Determination of hydraulic conductivity of fractured rock masses:A case study for a rock cavern project in Singapore

In order to reduce the risk associated with water seepage in an underground rock cavern project inSingapore, a reliable hydro-geological model should be established based on the in situ investigationdata. The key challenging issue in the hydro-geological model building is how to integrate limitedgeological and hydro-geological data to determine the hydraulic conductivity of the fractured rockmasses. Based on the data obtained from different stages （feasibility investigation stage, constructionstage, and post-construction stage）, suitable models and methods are proposed to determine the hydraulicconductivities at different locations and depths, which will be used at other locations in thefuture. 2015 Institute of Rock and Soil Mechanics, Chinese Academy of Sciences. Production and hosting byElsevier B.V. All rights reserved.

Flexible transparent wood enabled by epoxy resin and ethylene glycol diglycidyl ether

Transparent wood has potential application in intelligent building,solar cell,electronics,and other advanced materials,while its single functionability hinders its further development.Flexible transparent wood(FTW)was prepared by alkaline pretreatment and bleaching treat-ment of paulownia wood followed by impregnation of epoxy resin and ethylene glycol diglycidyl ether(EDGE).The eff ect of delignifi cation degree on the optical and mechani-cal properties of FTW was studied,and the infl uence of the epoxy/EDGE ratio on the fl exibility and mechanical proper-ties of FTW was also investigated.The results showed that higher delignifi cation degree resulted in higher transmit-tance of FTW.More EDGE addition led to better fl exibility of FTW,while overmuch addition of EDGE will reduce the mechanical properties.The optimal FTW sample resulted in a high transmittance of 89%and an ultrahigh haze value of 97%with outstanding fl exibility and excellent mechanical properties.The investigation of FTW broadens the research fi eld of transparent wood,and provides great possibility for its application in fl exible wearable devices and fl exible materials.

Frequencies Prediction of Laminated Timber Plates Using ANN Approach

Cross laminated timber(CLT)panels,which are used as load bearing plates and shear panels in timber structures,can serve as roofs,walls and floors.Since timber is construction material with relatively less stiffness,the design of such structures is often driven by serviceability criteria,such as deflection and vibration.Therefore,accurate vibration and elastic properties are vital for engineered CLT products.The objective of this research is to explore a method to determine the natural frequencies of orthotropic wood plates efficiently and fast.The method was developed based on vibration signal processing by wavelet to acquire the effective sample data,and a model developed by artificial neural network(ANN)to achieve the prediction of nature frequencies.First,experiments were performed to obtain vibration signals of single-layer plates.The vibration signals were then processed by wavelet packet transform to extract the eigenvectors,which served as the samples to train the ANN model.The trained model was employed to predict three nature frequencies of other test specimens.The results showed that the proposed method can produce predicted frequencies fast and efficiently within 10%of the measured values.

Stain capacity of three fungi on two fast-growing wood

We investigated the stain of fast-growing wood(Cunninghamia lanceolate,CL;Paulownia,PT)inoculated with three fungi(Arthrinium phaeospermum,AP;Vibrio anguillarum,VA;Aspergillacea,AS)to explore the new wood dyeing ways and the better combination of wood and fungi for dyeing.Only AP could dye on CL and PT.Especially for CL,its percentage of internal spalting,percentage of external spalting and dyeing depth were the highest(48%,15%and 5.06 mm,respectively).Surprisingly,the bigger weight loss occurs on PT.The results showed that the dyeing eff ect of AP dyeing CL was the best,and the wood color change was obviously(Orange to dark red).AP could produce more pigments than the other two fungi(VA;AS),CL was more suitable for fungus staining than PT,indicating that AP could off ered a new potential market and a chance for areas to earning higher income for CL.This research paves the way for improving color change was obviously(Orange to dark red).AP could produce more pigments than the other two fungi(VA;AS),CL was more suitable for fungus staining than PT,indicating that AP could off er a new potential market and a chance for areas to earn higher income for CL.

Anisotropic Superconducting Properties of Kagome Metal CsV_3Sb_5

We systematically measure the superconducting(SC)and mixed state properties of high-quality CsV_3 Sb_5 single crystals with T_c-3.5 K.We find that the upper critical field H_(c2)(T)exhibits a large anisotropic ratio of H_(c2)^(ab)/H_(c2)^c^9 at zero temperature and fitting its temperature dependence requires a minimum two-band effective model.Moreover,the ratio of the lower critical field,H_(c1)^(ab)/H_(c1)^c,is also found to be larger than 1,which indicates that the in-plane energy dispersion is strongly renormalized near Fermi energy.Both H_(c1)(T)and SC diamagnetic signal are found to change little initially below T_c-3.5 K and then to increase abruptly upon cooling to a characteristic temperature of-2.8 K.Furthermore,we identify a two-fold anisotropy of in-plane angular-dependent magnetoresistance in the mixed state.Interestingly,we find that,below the same characteristic T-2.8 K,the orientation of this two-fold anisotropy displays a peculiar twist by an angle of 60°characteristic of the Kagome geometry.Our results suggest an intriguing superconducting state emerging in the complex environment of Kagome lattice,which,at least,is partially driven by electron-electron correlation.

A density-wave-like transition in the polycrystalline V_(3)Sb_(2) sample with bilayer kagome lattice

Recently,transition-metal-based kagome metals have aroused much research interest as a novel platform to explore exotic topological quantum phenomena.Here we report on the synthesis,structure,and physical properties of a bilayer kagome lattice compound V_(3)Sb_(2).The polycrystalline V_(3)Sb_(2) samples were synthesized by conventional solid-state-reaction method in a sealed quartz tube at temperatures below 850℃.Measurements of magnetic susceptibility and resistivity revealed consistently a density-wave-like transition at Tdw≈160 K with a large thermal hysteresis,even though some sample-dependent behaviors were observed presumably due to the different preparation conditions.Upon cooling through Tdw,no strong anomaly in lattice parameters and no indication of symmetry lowering were detected in powder x-ray diffraction measurements.This transition can be suppressed completely by applying hydrostatic pressures of about 1.8 GPa,around which no sign of superconductivity was observed down to 1.5 K.Specific-heat measurements revealed a relatively large Sommerfeld coefficientγ=18.5 mJ·mol^(-1)·K^(-2),confirming the metallic ground state with moderate electronic correlations.Density functional theory calculations indicate that V_(3)Sb_(2) shows a non-trivial topological crystalline property.Thus,our study makes V_(3)Sb_(2) a new candidate of metallic kagome compound to study the interplay between density-wave-order,nontrivial band topology,and possible superconductivity.

Review of Financial Pressure

Different from foreign capital markets,china’s domestic capital markets are special,which also determines that the research on financial pressure starts from the reform of state-owned enterprises,and draws lessons from the relevant theories of financial risk and financial fraud,thus gradually forming a more diversified research results.

Drought decreases the positive impact of warming on an alpine grassland community

Temperature and precipitation are the main factors determining plant community succession and aboveground net primary productivity(ANPP)in natural grasslands.However,most climate manipulative experiments have mainly focused on their impacts in isolation,especially in alpine regions.Here we explored the relative effects and interaction of warming and precipitation alteration on succession and ANPP using a 7-year experiment involving warming with precipitation alteration(increase(IP)or decrease(DP))in precipitation relative to ambient precipitation(AP)on the Tibetan Plateau.Our results showed that warming and warm-wet conditions increased species richness,diversity index,height and cover of overall species.Conversely,decreasing precipitation reduced them,but increased S.purpurea and the rate of change in community composition.Importantly,warming mitigated the impacts of decreased precipitation on plant community composition,and the interactive effects of warming and altered precipitation on cover,height and plant ANPP varied with year and plant species.Generally,warming increased community ANPP through increases in forb ANPP or non-dominant species ANPP and biodiversity regardless of change in precipitation.However,decreased precipitation reduced community ANPP via decreases in the ANPP of sedges and forbs and biodiversity.Precipitation alteration affected the relationship between biodiversity and community ANPP regardless of warming(IP<AP<DP).Therefore,generally warming and decreased precipitation have opposite effects on ANPP in the alpine grassland,suggesting that warming mitigated the negative impacts of drought on the ANPP of the alpine grassland.

Germylene-Fe complexes caused by heterometallic coupling and investigation into the 3d-4p bonding

The interpretation of heterometallic bonding nature is a basic work of inorganic chemistry.By means of intermetallic substitution of germylene anions with iron halide complexes CpFe(CO)_(2)I andβ-diketiminato Fe^Ⅱchloride,the ferrogermylene complexes 3a,3b and 4a were synthesized and structurally characterized.The structural and IR characterizations show the presence of the Ge←Feπbackbonding in molecules 3a,3b and 4a.The computational works on frontier molecular orbitals and their comparison of energy states confirmed thatσdonation andπbackbonding are both weak in these molecules,despite three complexes have longer Ge-Fe bonds,whose strength decreases slightly with the degressive electron density around Fe environment in a sequence from 3a,3b to 4a.

高山嵩草植物群落花期物候对增水的响应比对恒定增温和逐步增温的响应更敏感

有研究表明长期观测的植物花期物候变化温度敏感性与野外控制恒定增温试验所得出的花期物候温度敏感性结果不一致,这可能是由于两种观测方法具有不同的增温模式引起的。因为长期观测的气候变暖实际上是气温逐渐升高的情景,而野外控制增温试验所增加的温度是突然增加且每年保持不变。不同的增温模式是否会导致不同的结果目前还缺乏野外试验证据。此外,不同增温模式的效应还受到降水变化的调控。因此,我们于2015–2018年在高寒高山嵩草草甸开展了一项恒定增温(和对照相比,每年保持恒定增温1°C)和逐步增温(和对照相比,2015年增温0.25°C,以后逐年在前一年基础上再增温0.25°C,到2018年相比对照增温1°C)以及与增水(100%/50%)耦合的野外控制试验。研究结果发现,增温模式并没有显著改变群落花期物候。然而,增水显著提前了早花植物和中花植物的初花期,提前了早花植物的末花期,推迟了中花植物的末花期。增水处理并没有显著改变早花植物的开花持续期,但却显著延长了中花植物的开花持续期,进而延长了该群落的开花持续期。增温速率和增水处理并没有显著的交互作用。前一年的干旱会显著抑制第二年该植物群落的现存最大开花数。因此,无论增温模式如何,降水的改变对该高山嵩草植物群落花期物候的影响要大于增温对其的影响。

导师制结合反思性教学在重症医学科实习护生带教中的作用研究

目的探讨导师制结合反思性教学在重症医学科实习护士带教中的作用。方法将2019年3月至10月在重症医学科实习的21名护士设为对照组,另将2019年12月至2020年7月实习的21名护士设为研究组。对照组采取传统带教,研究组采取导师制结合反思性教学。对比两组带教前后理论和技术操作考核成绩、带教前后职业自我效能感及带教前后临床综合能力。采用SPSS 26.0进行t检验和卡方检验,等级分布采用秩和检验。结果带教后两组理论和技术操作考核成绩等级分布对比差异均有统计学意义(P<0.05),研究组理论和技术操作考核成绩优良率均高于对照组(P<0.05);带教前两组护生职业自我效能感量表中工作职责和教育要求评分以及临床综合能力(观察病情能力、沟通能力、健康教育能力、人文关怀能力、应急能力、专业知识、准确执行医嘱能力、与医生配合能力)评分差异均无统计学意义(P>0.05),带教后两组护生职业自我效能感量表评分、临床综合能力评分均升高(P<0.05),研究组带教后实习护生职业自我效能感量表评分、综合能力评分均高于对照组(P<0.05)。结论在重症医学科实习护生带教中采用导师制结合反思性教学,可提高实习护生职业自我效能感,提升教学效果,并可提高实习护生临床综合素质。

Warming and grazing enhance litter decomposition and nutrient release independent of litter quality in an alpine meadow

Warming and grazing,and ltter quality jointly determine liter decomposition and nutrient releases in grazing ecosystems.However,their effects have previously been studied in isolation.We conducted a two factorial experiment with asymmetric warming using infrared heaters and moderate grazing in an alpine meadow.Litter samples were collected from all plots in each treatment,among which some subsamples were placed in their original plots and other samples were translocated to other treatment plots to test the relative effects of each treatment on litter decomposition and nutrient releases.We found that warming rather than grazing alone significantly increased total losses of litter mass,total organic carbon,total nitrogen(TN)and total phosphorus(TP)per unit area due to increases in both mass loss rates and ltter biomass.However,grazing with warming did not affect their total mass losses because increased mass loss was offset by decreased litter biomass compared with the control.Seasonal mean soil temperature better predicted litter decomposition than litter lignin content or carbon to nitrogen ratio.There were interactions between warming and grazing,but there were no interactions between them and litter quality on litter decomposition.The temperature sensitivity of TN loss was higher than that of TP loss per unit area.Our results suggest that increased temperature has a greater effect on litter decomposition and nutrient release than change in litter quality,and that more N release from litter could result in greater P deficiency in the alpine meadow.

Titanium doped kagome superconductor CsV_(3-x)Ti_(x)Sb_(5)and two distinct phases

The vanadium-based kagome superconductor CsV_(3)Sb_(5) has attracted tremendous attention due to its unexcepted anomalous Hall effect(AHE),charge density waves(CDWs),nematicity,and a pseudogap pair density wave(PDW)coexisting with unconventional strong-coupling superconductivity.The origins of CDWs,unconventional superconductivity,and their correlation with different electronic states in this kagome system are of great significance,but so far,are still under debate.Chemical doping in the kagome layer provides one of the most direct ways to reveal the intrinsic physics,but remains unexplored.Here,we report,for the first time,the synthesis of Ti-substituted CsV_(3)Sb_(5) single crystals and its rich phase diagram mapping the evolution of intertwining electronic states.The Ti atoms directly substitute for V in the kagome layers.CsV_(3-x)Ti_(x)Sb_(5) shows two distinct superconductivity phases upon substitution.The Ti slightly-substituted phase displays an unconventional V-shaped superconductivity gap,coexisting with weakening CDW,PDW,AHE,and nematicity.The Ti highly-substituted phase has a U-shaped superconductivity gap concomitant with a short-range rotation symmetry breaking CDW,while long-range CDW,twofold symmetry of in-plane resistivity,AHE,and PDW are absent.Furthermore,we also demonstrate the chemical substitution of V atoms with other elements such as Cr and Nb,showing a different modulation on the superconductivity phases and CDWs.These findings open up a way to synthesise a new family of doped CsV_(3)Sb_(5) materials,and further represent a new platform for tuning the different correlated electronic states and superconducting pairing in kagome superconductors.

欧洲国家专利盒政策介绍及对我国的启示

近年来,为激励企业创新,欧洲15个国家相继实施专利盒政策,对符合条件的知识产权转化和商品化所得给予大幅度的税收优惠。尤其是英国和爱尔兰通过专利盒政策的实施,在鼓励创新、刺激投资、增加就业等方面取得明显成效,值得我国借鉴。本文在对欧洲15个国家,特别是英国及爱尔兰专利盒政策介绍的基础上,与我国现有的创新激励税收优惠政策进行比较分析,提出了针对我国实际的政策建议。