摘要：A new electrical method of conductive carbon-film(with waterproof and anticorrosion ability)was proposed to continuously measure crack propagation rate of brittle rock under THMC coupling condition.A self-designed coupling testing system was used to conduct THMC coupling fracture tests of the pre-cracked red sandstone specimens(where the temperature is only changed)by this new electrical method of conductive *** results obtained by the energy method coincide well with the test *** the higher the temperature is,the earlier the crack is initiated and the larger the crack propagation rate and accelerated velocity are,which can prove the validity of the new electrical *** new electrical method has advantages of continuously measuring crack propagation rate over the conventional electrical,optical and acoustic methods,and can provide important basis for safety assessment and cracking-arrest design of deep rock mass engineering.

摘要：Based on analysis of thermo-hydro-mechanical-chemical(THMC)coupling mechanism for brittle rock,THMC coupling indicator in terms of rock porosity was introduced to represent the influencing degree of THMC coupling field on stress field in order to establish THMC coupling fracture criterion.A novel real-time measurement method of permeability(related to porosity)was proposed to determine the THMC coupling indicator,and self-designed THMC coupling tests and scanning electron microscope tests were conducted on pre-cracked red sandstone specimens to study the macroscopic and microscopic fracture *** results show that the higher the hydraulic pressure is,the smaller the crack initiation load is and the easier the Mode I fracture *** results are in good agreement with prediction results(crack initiation load and angle,and fracture mode),which can verify the effectiveness of the newly established THMC coupling fracture *** new fracture criterion can be also further extended to predict THMC coupling fracture of multi-crack problem.

摘要：向AI大模型提出高质量问题已成为数智时代学习者的必备技能与元素养。然而,当前学生向AI大模型提问的能力较低,所提问题存在浅表化、思维含量不高等现象,导致大模型的响应往往无法满足预期需求。苏格拉底式提问为有效提升学生提问质量提供了有益参考,基于此设计的苏格拉底式问题支架从“认知—元认知”双重维度提供了提示性、指导性、解释性三类支架,能够激发学生向AI大模型主动提问和持续追问的能力,有效促进学生认知发展。面向教育技术学专业44名本科生开展的准实验研究发现,使用该支架前后学生在问题深度、问题序列和问题架构方面具有明显变化。苏格拉底式问题支架能显著提高学生的深度提问能力,有效促进高阶问题序列转换,让学生形成分析创造式、深度理解式、评价创造式三种典型的转换循环,还能引导学生构建基于不同观点的星型、链式和闭环的问题架构逻辑。未来,教师应借助多样化的问题支架,引导学生向AI大模型提出高阶问题,并在追问中建立问题逻辑,以高质量的人机对话促进深度学习和学生高阶思维发展。

摘要：高通量表征技术在金属材料分析领域具有重要应用价值,它能够实现对金属材料进行跨尺度的全域分析,评价材料表面宏观特性、微观不均匀性及局部缺陷。辉光放电溅射可沿样品表面的纵深方向,以大尺寸、平坦且快速的方式逐层剥蚀样品,再将暴露出真实显微组织的样品送至多种分析仪器中进行成分、性能、组织结构的分析,从而作为金属材料的高通量表征样品前处理环节的关键设备。在传统Grimm型辉光溅射源的基础上,本研究搭建了一种专为高通量实验设计的辉光放电溅射系统,该系统将辉光溅射尺度由mm级扩展至cm级,同时实验发现了大尺寸溅射会导致辉光放电强度及溅射速率降低这一现象。针对这一现象,结合通过COMSOL Multiphysics仿真计算的辉光放电电子运动轨迹、电子密度以及化学反应速率等结果,该研究提出了一种通过施加扫描磁场来增强辉光放电光谱(GD-OES)强度以及溅射速率的方法。实验选用T2紫铜样品来探究扫描磁场的增强效果,结果表明,应用扫描磁场增强装置可获得更强的光谱信号强度及更快的溅射速率。在保持放电电压和电流不变的前提下,Mo、Cu元素的光谱强度分别增至无磁场时的1.43~11.97倍和1.13~26.50倍。其中,Mo元素光谱强度最大值可达53421 Cts,Cu元素光谱强度最大值可达76948 Cts,分别是无磁场时的6.86倍、4.32倍。此外,该方法可以显著地提高溅射速率,当阳极筒孔径为?15 mm时,T2紫铜样品的溅射速率提高了4.35倍,最高可达2662.09 nm·min^(-1)。使用白光干涉仪和金相显微镜对溅射坑表面的平整度和显微组织图像进行了采集,结果显示磁场引入对溅射坑表面粗糙度未产生显著影响,同时能清晰地呈现样品的真实显微组织特征。综上,实验结果证实,应用扫描磁场增强装置可在确保溅射平整度不受影响的前提下,实现光谱信号强度和溅射速率的提升,为解决大尺寸溅射引起的低溅射速率问题提供了新方法。

摘要：MAPK信号通路中的MKKs家族基因在水稻生长发育和防御信号传导中起承上启下的作用,并参与调控多种生物学过程。本研究通过生物信息学分析,鉴定了水稻中的MKKs基因,并构建了它们的系统发育树,揭示了MKKs家族基因的保守性和多样性。利用基因编辑技术,编辑日本晴水稻品种中Os MKK4基因,成功获得了6种该基因不同突变类型的材料,其粒长、粒宽和千粒重均较野生型显著降低。单倍型分析结果表明,Os MKK4基因的单倍型有明显的籼粳分化,主要为Glu^(14)粳型和Leu^(14)籼型。含有Glu^(14)粳型稻的平均粒长较低,平均粒宽和千粒重较高。此外,将Kasalath中带有Leu^(14)单倍型的Os MKK4基因导入日本晴,导致DHX(CSSL)的粒长、粒宽和千粒重较日本晴显著降低;与Kasalath相比,代换系的粒宽和千粒重显著增加。本研究探索了Os MKK4基因的重要单倍型对水稻籽粒的影响,为更精确的分子设计育种提供基因资源和策略。

摘要：A damage assessment methodology based on the Hashin failure theory for glass fiber reinforced polymer(GFRP)composite blade is proposed. The typical failure mechanisms including the fiber tension/compression and matrix tension/compression are considered to describe the damage behaviors. To give the flapwise and edgewise loading along the blade span, the Blade Element Momentum Theory(BEMT) is adopted. In conjunction with the hydrodynamic analysis, the structural analysis of the composite blade is cooperatively performed with the Hashin damage model. The damage characteristics of the composite blade, under normal and extreme operational conditions,are comparatively analyzed. Numerical results demonstrate that the matrix tension damage is the most significant failure mode which occurs in the mid-span of the blade. The blade internal configurations including the box-beam, Ibeam, left-C beam and right-C beam are compared and analyzed. The GFRP and carbon fiber reinforced polymer(CFRP) are considered and combined. Numerical results show that the I-beam is the best structural type. The structural performance of composite tidal turbine blades could be improved by combining the GFRP and CFRP structure considering the damage and cost-effectiveness synthetically.

摘要：本文由两部分构成。第一部分详细分析了音乐电视创意元素,从歌手设计、运动设计、色彩设计三个方面分析了不同创意元素在音乐电视成片中的作用与功能;第二部分主要论述了音乐电视创意元素的整合,从画面创意和结构创意两方面例证了整合的方法与要点,并针对两大基本结构类型叙事情节型和情绪感受型提出了各自的创意方法。全文通过音乐电视创意元素构成与整合的分析,阐释了音乐电视主要的创意方法和创意路径,强调了创意元素的整合在音乐电视制作中的重要性。

摘要：By spraying concrete on inner surface,air-supported fabric structures can be used as formwork to construct reinforced concrete shell *** fabric formwork has the finished form of concrete *** deviation from the desired shape of concrete shells still remains as central problem due to dead weight of concrete and less stiffness of fabric *** can be used not only as a bonding layer between fabrics and concrete but also as an additional stiffening ***,there is little research on mechanical behaviors of the polyurethane shell *** paper presents experimental studies on an inflated fabric model with and without polyurethane,including relief pressure tests,vertical loading tests and horizontal loading *** results show that the additional polyurethane layer can significantly enhance the stiffness of the fabric *** with the experiment,a numerical model using shell layered finite elements has a good *** reinforcement by polyurethane to improve stiffness of air-supported fabric formwork is expected to be considered in the design and construction of the concrete shell,especially dealing with the advance of shape-control.

摘要：Steering control for an autonomous underwater glider （AUG） is very challenging due to its changing dynamic char- acteristics such as payload and shape. A good choice to solve this problem is online system identification via in-field trials to capture current dynamic characteristics for control law reconfiguration. Hence, an online polynomial estimator is designed to update the yaw dynamic model of the AUG, and an adaptive model predictive control （MPC） controller is used to calculate the optimal control command based on updated estimated parameters. The MPC controller uses a quadratic program （QP） to compute the optimal control command based on a user-defined cost function. The cost function has two terms, focusing on output reference tracking and move suppression of input, respectively. Move-suppression performance can, at some level, represent energy-saving performance of the MPC controller. Users can balance these two competitive control performances by tuning weights. We have compared the control performance using the second-order polynomial model to that using the filth-order polynomial model, and found that the tbrmer cannot capture the main characteristics of yaw dynamics and may result in vibration during the flight. Both processor-in-loop （PIL） simulations and in-lake tests are presented to validate our steering control performance.

摘要：A 500 N model engine filled with LO2/GCH4 was designed and manufactured.A series of ignition attempts were performed in it by both head spark plug and body spark *** show that the engine can be ignited but the combustion cannot be sustained when head spark plug applied as the plug tip was set in the gaseous low-velocity zone with thin *** is mainly because flame from this zone cannot supply enough ignition energy for the whole ***,reliable ignition and stable combustion can be achieved by body spark *** the O/F ratio increases from 2.61 to 3.49,chamber pressure increases from 0.474 to 0.925 MPa and combustion efficiency increases from 57.8%to 95.1%.This is determined by the injector configuration,which cannot produce the sufficiently breakup of the liquid oxygen on the low flow rate case.