Magneto‑Dielectric Synergy and Multiscale Hierarchical Structure Design Enable Flexible Multipurpose Microwave Absorption and Infrared Stealth Compatibility

Developing advanced stealth devices to cope with radar-infrared(IR)fusion detection and diverse application scenarios is increasingly demanded,which faces significant challenges due to conflicting microwave and IR cloaking mechanisms and functional integration limitations.Here,we propose a multiscale hierarchical structure design,integrating wrinkled MXene IR shielding layer and flexible Fe_(3)O_(4)@C/PDMS microwave absorption layer.The top wrinkled MXene layer induces the intensive diffuse reflection effect,shielding IR radiation signals while allowing microwave to pass through.Meanwhile,the permeable microwaves are assimilated into the bottom Fe_(3)O_(4)@C/PDMS layer via strong magneto-electric synergy.Through theoretical and experimental optimization,the assembled stealth devices realize a near-perfect stealth capability in both X-band(8–12 GHz)and long-wave infrared(8–14μm)wavelength ranges.Specifically,it delivers a radar cross-section reduction of−20 dB m^(2),a large apparent temperature modulation range(ΔT=70℃),and a low average IR emissivity of 0.35.Additionally,the optimal device demonstrates exceptional curved surface conformability,self-cleaning capability(contact angle≈129°),and abrasion resistance(recovery time≈5 s).This design strategy promotes the development of multispectral stealth technology and reinforces its applicability and durability in complex and hostile environments.

Role of heterogenous microstructure and deformation behavior in achieving superior strength-ductility synergy in zinc fabricated via laser powder bed fusion

Zinc(Zn)is considered a promising biodegradable metal for implant applications due to its appropriate degradability and favorable osteogenesis properties.In this work,laser powder bed fusion(LPBF)additive manufacturing was employed to fabricate pure Zn with a heterogeneous microstructure and exceptional strength-ductility synergy.An optimized processing window of LPBF was established for printing Zn samples with relative densities greater than 99%using a laser power range of 80∼90 W and a scanning speed of 900 mm s−1.The Zn sample printed with a power of 80 W at a speed of 900 mm s−1 exhibited a hierarchical heterogeneous microstructure consisting of millimeter-scale molten pool boundaries,micrometer-scale bimodal grains,and nanometer-scale pre-existing dislocations,due to rapid cooling rates and significant thermal gradients formed in the molten pools.The printed sample exhibited the highest ductility of∼12.1%among all reported LPBF-printed pure Zn to date with appreciable ultimate tensile strength(∼128.7 MPa).Such superior strength-ductility synergy can be attributed to the presence of multiple deformation mechanisms that are primarily governed by heterogeneous deformation-induced hardening resulting from the alternative arrangement of bimodal Zn grains with pre-existing dislocations.Additionally,continuous strain hardening was facilitated through the interactions between deformation twins,grains and dislocations as strain accumulated,further contributing to the superior strength-ductility synergy.These findings provide valuable insights into the deformation behavior and mechanisms underlying exceptional mechanical properties of LPBF-printed Zn and its alloys for implant applications.

Confinement and synergy effects of supported-confined bimetal catalysts with superior stability and catalytic activity

Bimetallic nanocrystals have attracted considerable attention because of their complicated systems,which are far superior to those of their individual constituents.A TiO_(2)-confined PtMnP bimetallic catalyst(PtMnP@TiO_(2)) was prepared using an ultrasonic-assisted coincident strategy,which demonstrated exceptional catalytic activity in the universal hydrogen evolution reaction (HER).Owing to the bimetallic synergistic effect and TiO_(2) confinement,PtMnP@TiO_(x)showed ultrasmall metal nanoparticles (NPs),a higher active Pt^(0) content,adequate activation at the porous surface,and abundant acid sites.Simulations were performed to visualize the strain properties of Mn and Pt during the bending process and demonstrate the high activity of Pt.The Pt-Mn bimetallic catalysts were enriched with Pt NPs,convoyed by electron transfer from Mn to Pt.Briefly,PtMnP@TiO_(2) showed robust evolution reaction activities (an overpotential of 220 mV at a current density of 10 mA cm^(-2) and a Tafel slope of 186 mV dec^(-1))and the ability to contrast stated catalysts without ultrasonication-plasma.This protocol revealed that the geometrical and electronic effects of Pt and P surrounding the Mn species in PtMnP@TiO_(2) were crucial for increasing the catalytic activity (99%) and durability (over 20 cycles),which were far superior to those of other reported catalysts.

Synergy of inside doped metals–Outside coated graphene to enhance hydrogen storage in magnesium-based alloys

Grain growth of magnesium(Mg)and its hydride is one of the main reasons for kinetic and capacity degradation during the hydrogen absorption and desorption cycles.To solve this problem,herein we propose a novel method involving synergistic effect of inside embedded metals and outside coated graphene to limit the growth of Mg and its hydride grains.The graphene coated Mg-Y-Al alloys were selected as a model system for demonstrating this positive effect where the Mg_(91)Y_(3)Al_(6)alloy was first prepared by rapidly solidified method and then high-pressure milled with 5 wt%graphene upon 5 MPa hydrogen gas for obtaining in-situ formed YAl_(2)and YH_(3)embedded in the MgH_(2)matrix with graphene shell(denoted as MgH_(2)-Y-Al@GR).In comparison to pure MgH_(2),the obtained MgH_(2)-Y-Al@GR composites deliver much better kinetics and more stable cyclic performance.For instance,the MgH_(2)-Y-Al@GR can release about 6.1 wt%H_(2)within 30 min at 300℃ but pure MgH_(2)only desorbs∼1.5 wt%H_(2).The activation energy for desorption of MgH_(2)-Y-Al@GR samples is calculated to be 75.3±9.1 kJ/mol that is much lower than approximately 160 kJ/mol for pure MgH_(2).Moreover,its capacity retention is promoted from∼57%of pure MgH_(2)to∼84%after 50th cycles without obvious particle agglomeration and grain growth.The synergistic effect of outside graphene coating with inside embedded metals which could provide a huge number of active sites for catalysis as well as inhibit the grain growth of Mg and its hydride is believed to be responsible for these.

Tuning synergy between nickel and iron in Ruddlesden-Popper perovskites through controllable crystal dimensionalities towards enhanced oxygenevolving activity and stability

Ni-Fe-based oxides are among the most promising catalysts developed to date for the bottleneck oxygen evolution reaction(OER)in water electrolysis.However,understanding and mastering the synergy of Ni and Fe remain challenging.Herein,we report that the synergy between Ni and Fe can be tailored by crystal dimensionality of Ni,Fe-contained Ruddlesden-Popper(RP)-type perovskites(La_(0.125)Sr_(0.875))n+1(Ni_(0.25)Fe_(0.75))nO3n+1(n=1,2,3),where the material with n=3 shows the best OER performance in alkaline media.Soft X-ray absorption spectroscopy spectra before and after OER reveal that the material with n=3 shows enhanced Ni/Fe-O covalency to boost the electron transfer as compared to those with n=1 and n=2.Further experimental investigations demonstrate that the Fe ion is the active site and the Ni ion is the stable site in this system,where such unique synergy reaches the optimum at n=3.Besides,as n increases,the proportion of unstable rock-salt layers accordingly decreases and the leaching of ions(especially Sr^(2+))into the electrolyte is suppressed,which induces a decrease in the leaching of active Fe ions,ultimately leading to enhanced stability.This work provides a new avenue for rational catalyst design through the dimensional strategy.

Tailoring the microenvironment of Ti sites in Ti-containing materials for synergizing with Au sites to boost propylene epoxidation

Au sites supported on Ti-containing materials(Au/Ti-containing catalyst)are currently considered as a promising catalyst for the propylene epoxidation owing to the synergistic effect that hydrogen peroxide species formed on Au sites diffuses to the Ti sites to form the Ti-hydroperoxo intermedi-ates and contributes to the formation of propylene oxide(PO).In principle,thermal treatment will significantly affect the chemical and physical structures of Ti-containing materials.Consequently,the synergy between tailored Ti sites with different surface properties and Au sites is highly expected to enhance the catalytic performance for the reaction.Herein,we systematically studied the intrinsic effects of different microenvironments around Ti sites on the PO adsorption/desorption and conversion,and then effectively improved the catalytic performance by tailoring the number of surface hydroxyl groups.The Ti^(Ⅵ) material with fewer hydroxyls stimulates a remarkable enhancement in PO selectivity and H_(2) efficiency compared to the Ti^(Ⅵ) material that possessed more hydroxyls,offering a 7-fold and 4-fold increase,respectively.As expected,the Ti^(Ⅵ+Ⅳ) and Ti^(Ⅳ) materials also exhibit a similar phenomenon to the Ti^(Ⅵ) materials through the same thermal treatment,which strongly supports that the Ti sites microenvironment is an important factor in suppressing PO con-version and enhancing catalytic performance.These insights could provide guidance for the rational preparation and optimization of Ti-containing materials synergizing with Au catalysts for propylene epoxidation.

Trade-offs and synergies between ecosystem services in Yutian County along the Keriya River Basin,Northwest China

The Keriya River Basin is located in an extremely arid climate zone on the southern edge of the Tarim Basin of Northwest China,exhibiting typical mountain-oasis-desert distribution characteristics.In recent decades,climate change and human activities have exerted significant impacts on the service functions of watershed ecosystems.However,the trade-offs and synergies between ecosystem services(ESs)have not been thoroughly examined.This study aims to reveal the spatiotemporal changes in ESs within the Keriya River Basin from 1995 to 2020 as well as the trade-offs and synergies between ESs.Leveraging the Integrated Valuation of Ecosystem Services and Trade-offs(InVEST)and Revised Wind Erosion Equation(RWEQ)using land use/land cover(LULC),climate,vegetation,soil,and hydrological data,we quantified the spatiotemporal changes in the five principal ESs(carbon storage,water yield,food production,wind and sand prevention,and habitat quality)of the watershed from 1995 to 2020.Spearman correlation coefficients were used to analyze the trade-offs and synergies between ES pairs.The findings reveal that water yield,carbon storage,and habitat quality exhibited relatively high levels in the upstream,while food production and wind and sand prevention dominated the midstream and downstream,respectively.Furthermore,carbon storage,food production,wind and sand prevention,and habitat quality demonstrated an increase at the watershed scale while water yield exhibited a decline from 1995 to 2020.Specifically,carbon storage,wind and sand prevention,and habitat quality presented an upward trend in the upstream but downward trend in the midstream and downstream.Food production in the midstream showed a continuously increasing trend during the study period.Trade-off relationships were identified between water yield and wind and sand prevention,water yield and carbon storage,food production and water yield,and habitat quality and wind and sand prevention.Prominent temporal and spatial synergistic relationships were observed between different ESs,notably between carbon storage and habitat quality,carbon storage and food production,food production and wind and sand prevention,and food production and habitat quality.Water resources emerged as a decisive factor for the sustainable development of the basin,thus highlighting the intricate trade-offs and synergies between water yield and the other four services,particularly the relationship with food production,which warrants further attention.This research is of great significance for the protection and sustainable development of river basins in arid areas.

Trade-Offs and Synergie Effects of Regulating Ecosystem Services along an Climatic Gradient in Slovakia

This study aims to assess the synergies and trade-offs of regulating ecosystem services. Ecosystem services are non-linearly interconnected and changes in one service can positively or negatively affect another. We evaluated ecosystem services based on biophysical indicators using an expert scoring system that determines the corresponding soil functions and is part of the existing databases available in Slovakia. This methodological combination enabled us to provide unique mapping and assessment of ecosystem services within Slovakia. Correlation analysis between individual regulating ecosystem services and climate regions, slope, texture, and altitude confirm the statistically significant influence of climate and slope in all agricultural land, arable land, and grassland ecosystems. Statistically significant synergistic effects were established between the regulation of the water regime and the regulation of soil erosion within each climate region, apart from the very warm climate region. Only in a very warm climate region was potential of regulating ecosystem services mutually beneficial for soil erosion control and soil cleaning potential (immobilization of inorganic pollutants).

医科达Synergy医用电子直线加速器故障维修六例

放射治疗是利用放射线治疗肿瘤的医疗方式[1]。医用电子直线加速器作为医院开展放射治疗的重要医疗设备,在肿瘤治疗中发挥重要作用。同时,医用电子直线加速器的技术结构复杂,组成模块、系统、零部件多,集成度高,设备具有“唯一性”、故障风险大等特点,如出现故障不能及时解决,可影响患者治疗效果,严重时甚至会造成不可逆性的重大损伤[2]。目前,医科达Synergy医用电子直线加速器的市场占有率较高,其通信模块较多、运动结构相对复杂,故障率较高。本研究以我院在用的医科达Synergy医用电子直线加速器为例,对其结构原理及6例故障维修过程进行总结分析,以供同行借鉴和参考。

Spatiotemporal variations in ecosystem services and their trade-offs and synergies against the background of the gully control and land consolidation project on the Loess Plateau,China

Studying the spatiotemporal variations in ecosystem services and their interrelationships on the Loess Plateau against the background of the gully control and land consolidation(GCLC)project has significant implications for ecological protection and quality development of the Yellow River Basin.Therefore,in this study,we took Yan'an City,Shaanxi Province of China,as the study area,selected four typical ecosystem services,including soil conservation service,water yield service,carbon storage service,and habitat quality service,and quantitatively evaluated the spatiotemporal variation characteristics and trade-offs and synergies of ecosystem services from 2010 to 2018 using the Integrated Valuation of Ecosystem Services and Trade-offs(InVEST)model.We also analysed the relationship between the GCLC project and regional ecosystem service changes in various regions(including 1 city,2 districts,and 10 counties)of Yan'an City and proposed a coordinated development strategy between the GCLC project and the ecological environment.The results showed that,from 2010 to 2018,soil conservation service decreased by 7.76%,while the other three ecosystem services changed relatively little,with water yield service increasing by 0.56% and carbon storage service and habitat quality service decreasing by 0.16% and 0.14%,respectively.The ecological environment of Yan'an City developed in a balanced way between 2010 and 2018,and the four ecosystem services showed synergistic relationships,among which the synergistic relationships between soil conservation service and water yield service and between carbon storage service and habitat quality service were significant.The GCLC project had a negative impact on the ecosystem services of Yan'an City,and the impact on carbon storage service was more significant.This study provides a theoretical basis for the scientific evaluation of the ecological benefits of the GCLC project and the realization of a win-win situation between food security and ecological security.

数字化与绿色化协同转型如何赋能高质量发展——来自中国上市公司的证据

当前中国正处于数字化与绿色化两大战略历史交汇点,探索数字化和绿色化协同转型如何赋能经济高质量发展具有十分重要的现实意义。通过构建企业层面数字化与绿色化协同转型指标,以2007—2022年中国上市公司为研究样本,探究双化协同对企业高质量发展的影响。研究发现,相较于数字化或绿色化单一转型,双化协同能够更高效地提升企业全要素生产率,赋能企业高质量发展。机制分析发现,双化协同会综合单一转型优势,同时产生资源协同效应和创新协同效应优化企业资源配置、拓展企业知识宽度和提升企业创新质量,进而有效地驱动企业高质量发展。异质性分析发现,在内部特征方面,双化协同对国有、大规模以及重污染企业高质量发展的促进作用更大;在外部环境方面,双化协同对高质量发展的提升作用更易在处于市场竞争程度更大、环境规制强度更高,以及经营环境不确定性程度更低的企业中得到充分体现。因此,应加强顶层设计和体制机制优化,确保数字化与绿色化两大战略的有效实施和深度融合;企业要认清双化协同的积极效能,助力企业高质量发展;企业要深入了解其面临的内外部环境特征,以最大化双化协同的经济效用。

新型多通道扭带强化传热性能的数值模拟

采用数值模拟的方法,研究了内插具有交替顺、逆时针扭转方向(C-CC)结构的多通道扭带的换热管在Re=6000~12000范围内的流动传热特性。模拟结果表明,插有C-CC结构多通道扭带的换热管的Nu与通道数量(N)和Re呈正相关,与扭转比(T_(R))负相关,相对于经典扭带(N=2)最高提升了30.7%;摩擦系数与N呈正相关,与Re和T_(R)负相关,相对于经典扭带最高增加了304%;综合换热因子与Re和N呈负相关,随T_(R)的增加先增加后减小,最高为0.887。较小T_(R)时,所研究的新型C-CC结构多通道扭带有着比常规多通道扭带更好的强化传热性能。

复杂系统视角下粮食产业“三链协同”建构及优化策略

“三链协同”是推动粮食产业转向高质量发展的重要抓手。面对粮食产业“三链协同”式发展,传统的系统理论分析框架难以深入论证其中机制,复杂系统理论提供了一个更加全面精准的分析视角。基于复杂系统视角,实现粮食产业“三链协同”必须从过程和结果两个维度准确把握其内涵与外延,进而构建“节点—连边—整体”三维分析框架。对应到实践层面,当前“三链协同”仍存在资源错配现象突出、产业链条韧性不足、系统协作效率较低、内生动力有待激发等关键问题。为确保“三链协同”有序推进,应着重从资源整合逻辑、链条协同逻辑、系统演化逻辑入手,厘清“三链协同”系统的构建思路,在资源整合、激励约束、科技创新、协同治理等方面进行整体优化,以期推动粮食产业“三链协同”式高质量发展,加快实现我国由粮食大国向粮食强国的迈进。

协同育人视域下高职院校课程思政建设路径研究

协同论认为,协同工作能促进复杂系统独立存在的子系统由无序转向规律和高效。近年来许多高职院校在创新课程思政教学改革方面取得显著成效,但也存在主体认知参差不齐、沟通协作不够、支持保障不足等现实困境。基于协同论的启示,进一步从“内化目标、增强共识”“提升能力加强协作”“建立机制、做好保障”三方面优化课程思政协同育人的路径方法。

Synergy Decision for Radar and IRST Data Fusion

A new synergy decision method for radar and infrared search and track (IRST) data fusion is proposed, to solve such problems as how to decrease opportunities for radar suffering from being locked on by adverse electronic support measures (ESM), how to retrieve range information of the target during radar off, and how to detect the maneuver of the target. Firstly, polynomials used to predict target motion states are constructed. Secondly, a set of discriminants for detecting target maneuver are established by comparing the predicted values with the observations from IRST. Thirdly, a set of decisions are presented. Lastly, simulation is performed on the given scenario to test the validity of the method.

医科达Synergy医用直线加速器运动故障分析与处理

放射治疗是目前肿瘤治疗的主要手段之一,随着科学技术的发展,医用电子直线加速器已成为现代放射治疗领域的主流设备。南通市肿瘤医院2012年和2015年先后引进2台瑞典医科达Synergy高能医用电子直线加速器,该直线加速器为360 °旋转的鼓状结构,加速管为行波加速管,真空器件（如枪灯丝等）可以拆卸更换,能产生多档高能X射线和电子线,配备XVI和iViewGT影像平板,满足各种类型与不同部位的深度肿瘤放射治疗。

医科达Synergy加速器多叶准直器常见故障维修

0引言 随着精确放疗技术在临床上的广泛应用,多叶准直器已经成为医用直线加速器的标准配置。医科达Synergy医用直线加速器采用内置式多叶准直器,由40对叶片、光学系统部分（反光点、摄像机、光源、反光镜）、电路控制与传输部分（电信号控制处理、电动机驱动部分）、机械部分（电动机、丝杆部分）等组成。

川西高原生态系统服务功能权衡协同关系及其归因分析

[目的]分析川西高原3种关键生态系统服务的权衡协同关系,揭示自然因素的影响机制,进而为川西高原的可持续发展提供科学支撑。[方法]基于InVEST模型评估并分析了川西高原2000年、2005年、2010年、2015年、2020年水源涵养、土壤保持和碳存储3种生态系统服务功能及其时空分布特征,利用双变量Moran′s I指数分析了川西高原生态系统服务功能间的权衡协同关系,使用冗余分析揭示了各生态系统服务功能的影响因素。[结果]川西高原多年平均水源涵养量为249.24 mm,土壤保持量为226.18 t/hm^(2),碳存储量为118.56 t/hm^(2)。土壤保持和水源涵养功能之间以及水源涵养和碳存储功能之间的协同关系呈增强趋势,土壤保持和碳存储功能之间的协同关系保持稳定。[结论]2000—2020年,协同关系是川西高原水源涵养、土壤保持和碳存储功能之间的主导关系,水源涵养主要受降水和气温影响,土壤保持主要受林地、灌木和降水影响,碳存储主要受林地和灌木影响。

农业“水-能源-粮食”系统协同的生态效应

厘清农业“水—能源—粮食”系统协同的生态效应对于促进农业绿色低碳发展具有重要意义。为此,基于中国2000—2021年的省际面板数据,采用双向固定效应模型考察农业“水—能源—粮食”系统协同对农业生态环境的影响,而后构建中介效应模型和调节效应模型进一步明晰二者间的作用机制。研究结果显示:(1)农业“水—能源—粮食”系统协同能够显著提高农业生态环境质量,且经过一系列稳健性检验后结论依然成立。(2)异质性分析表明,农业“水—能源—粮食”系统协同的生态效应在粮食主产区和中西部地区更加显著。(3)作用机制检验发现,农业“水—能源—粮食”系统协同主要通过规模化经营和种植结构调整提高农业生态环境质量,环境规制在农业“水—能源—粮食”系统协同的生态效应中产生正向调节作用。基于此,需建立以水资源节约集约利用为核心的粮食高质量发展机制;重视规模化经营及种植结构调整在提高农业生态环境质量中发挥的重要作用;积极探索差异化的区域农业“水—能源—粮食”协同政策;不断完善农业环保政策。

水基钻井液用多元协同纳米润滑剂的研究进展

纳米技术在钻井液中的应用是目前油田化学领域的研究热点之一,受到国内外钻井液行业的普遍关注。随着纳米粒子的研究越来越深入,国内外已开始将其用于钻井液润滑改性,其用量少、对环境潜在的负面影响小,开发与应用新型环保钻井液纳米润滑剂是当前的发展趋势。本文围绕钻井液用纳米润滑材料的研究进展进行了详细的综述,包含纳米材料抗磨减摩机理、纳米粒子种类及形态、纳米材料在钻井液中的润滑效果,指出了纳米润滑材料应用于钻井液存在的问题,重点探讨了纳米粒子表面修饰改性进展并对多元协同及多效发挥进行了展望。