摘要：The paper proposes a topology optimization method for 1D phononic structures to minimize the tangential component of particle velocity at the objective *** tangential derivative of the boundary integral equation(TDBIE)is employed for the evaluation of the objective function involves the tangential derivative *** topological derivative is derived through the adjoint method and the Neumann boundary condition of the adjoint field is obtained using the *** average topological derivative which is obtained by calculating the average value of the topological derivative in each layer of design domains,is employed for the updating of the level set *** implementations demonstrate the proposed method is effective for the design of the 1D phononic crystals with the objective function involving tangential derivative quantities.

摘要：许多研究人员研究过充填作为岩层支护要素的作用.为评价充填对采场稳定性的作用和为采场设计确定适当准则,了解岩石和充填体的相互作用是必不可少的.问题的复杂性在于计算机模拟和物理模拟难以恰当地描述,为使问题适应这些方法,必须作一些假定来简化问题,因此模型是否具有真实的代表性总有一些怀疑.为克服这些缺陷,详细而广泛的现场数据能更好地了解充填的效应.为研究矿山充填对采矿诱发应力应变的影响,作者进行了广泛研究,这一研究包括两个矿山现场,历时5年.第一个矿山是薄矿脉,第二个为厚大矿体,包括各种现场测试仪器、现场试验和现场详细地质力学研究.文章以第二个矿山(BouchardHebert矿)的较大采场的研究为基础,介绍了现场测试仪器的潜力和测试方法,并从岩体和充填体相互作用的观点讨论了膏体充填的作用.

摘要：Based on the blasting theory and stress wave theory, stemming mechanism and movement of stemmed material in rock blasting were analyzed and the calculation expression of stemming lengths was deduced. The blasting experiment with different stemming lengths was carried out and the results show that the theoretical stemming length, which is 0.73 ~ 0.8 time of burden, is in the range of the experiential length, which is O. 63 - O. 88 time of burden. The blasting results of field experiments with theoretical stemming length are satisfactory, which shows the theoretical derivation and analysis are correct and reliable. The results will supply rock blasting with the theoretical gist of parameters design.

摘要：In the event of an instantaneous valve closure, the pressure transmitted to a surge tank induces the mass fluctuations that can cause high amplitude of water-level fluctuation in the surge tank for a reasonable cross-sectional area. The height of the surge tank is then designed using this high water level mark generated by the completely closed penstock valve. Using a conical surge tank with a non-constant cross-sectional area can resolve the problems of space and height. When addressing issues in designing open surge tanks, key parameters are usually calculated by using complex equations, which may become cumbersome when multiple iterations are required. A more effective alternative in obtaining these values is the use of simple charts. Firstly, this paper presents and describes the equations used to design open conical surge tanks. Secondly, it introduces user-friendly charts that can be used in the design of cylindrical and conical open surge tanks. The contribution can be a benefit for practicing engineers in this field. A case study is also presented to illustrate the use of these design charts. The case study’s results show that key parameters obtained via successive approximation method required 26 iterations or complex calculations, whereas these values can be obtained by simple reading of the proposed chart. The use of charts to help surge tanks designing, in the case of preliminary designs, can save time and increase design efficiency, while reducing calculation errors.

摘要：The intrinsic drawbacks of electrolytes and the growth of lithium dendrites limit the development of commercial lithium *** address the aforementioned challenges,a novel biomimetic brain-like nanostructure(BBLN)solid polymer electrolyte was created by manipulating the shape of the incorporated *** designed BBLN solid polymer electrolyte was created by incorporating spherical core-shell(UIO-66@67)fillers into polymer electrolyte,which is significantly different from traditional polymer-based composite ***-66@67 spherical nanoparticles are highly favorable to eliminating polymer electrolyte stress and deformation during solidification,indicating a great potential for fabricating highly uniform BBLN solid polymer electrolytes with a substantial number of continuous ***,spherical nanoparticles can significantly reduce the crystalline structure of polymer electrolytes,improving polymer chain segmental movement and providing continuous pathways for rapid ion *** a result,BBLN solid polymer electrolyte shows excellent ionic conductivity(9.2×10^(−4)S cm^(−1)),a high lithium transference number(0.74),and outstanding cycle stability against lithium electrodes over 6500 h at room *** concept of biomimetic brain-like nanostructures in this work demonstrates a novel strategy to enhance ion transport in polymerbased electrolytes for solid-state batteries.

摘要：针对利用深孔预裂爆破技术对低透气性煤层进行强化增透过程中爆生应力波能量弱、衰减快、信噪比低的现状,对爆破孔装药结构提出了改进方案,建立了耦合装药对爆破孔孔壁透射波能量和爆炸载荷影响特性的数值计算模型,利用Matlab编程技术对此数值计算模型进行了计算并获得解析解。在淮南矿业集团顾桥矿进行了爆生应力波能量受耦合装药系数ξ变化的影响特性的现场实验,对基于功率谱的能量分析法进行了改进,并利用此分析法对实验数据进行分析。数值计算和现场实验均表明:随ξ的增大应力波总能量反而减小;当ξ为1.5时,应力波信号在10~50 Hz频段的能量最强,且信噪比也最高。因而在爆破增透实施过程中应将耦合装药系数ξ设计为1.5左右,从而获得最佳的增透半径和增透效果。

摘要：Layered double hydroxides(LDHs),a class of two-dimensional(2D)brucite-like layers,have been effectively applied in diverse ***,the current synthesis methods restrict the in situ scaling-up and tunable production of LDH-based *** by the growing characteristic of“Bryophyllum pinnatum”,a sacrificial co-sputtered Zn-Al transition layer was introduced for the first time to in situ grow a scalable-manufactured and thickness-controllable LDH film on arbitrary substrate materials with flexible shapes through“partial dissolution”and“solution infiltration”*** LDH films could be tailored by the creative regulation of the component,structure and surface state of the transition *** showed that the as-prepared LDH film had strong mechanical robustness under harsh abrasion conditions due to its large thickness and multi-level ***,a series of galvanic couple model experiments based on Zn/Al single-metal transition layers were designed to solve the real-time monitoring issue in the complex hydrothermal *** work not only develops a new strategy to design and grow in situ LDH films with multifaceted features,but also reveals sophisticated LDH formation ***,the findings of this study may broaden the practical application of LDH-based materials toward advanced and smart devices.

摘要：在煤系地层中,与完整坚硬岩石不同,煤体松软破碎、强度低。受地应力和开采扰动的影响,松软破碎煤体内部裂隙进一步发育,强度进一步弱化,很难获得标准的完整煤样进行常规的拉压剪力学测试。煤体力学参数的缺失增加了采煤、掘进、支护和瓦斯抽采等采矿活动的风险。因此,探究新的力学实验方法对于煤矿生产活动非常有必要。文章采用纳米压痕技术测试破碎煤体的硬度、弹性模量和断裂韧度,分析了不同力学参数之间的联系。纳米压痕实验设计4个峰值荷载,每个峰值荷载进行12次实验,阐述了煤的力学特性与峰值荷载之间的关系。结合X射线衍射和扫描电镜实验,讨论了煤样矿物组分对其力学性质的影响规律。实验结果表明,峰值荷载在1~30 mN,煤的硬度和弹性模量不随峰值荷载的增加而明显变化;然而,煤的断裂韧度随峰值荷载的增加有增大的趋势。峰值荷载为1,5,10和30 mN时,煤的平均断裂韧度为0.40,0.36,0.61和0.77 MPa·m0.5。煤的纳米压痕硬度、弹性模量和断裂韧度具有明显的线性关系。硬度和弹性模量之间的线性关系与峰值荷载无关;断裂韧度与弹性模量之间的线性关系受峰值荷载的影响。煤是以有机质为基体的非均质岩土材料,其力学性质和矿物组分密切相关。石英强度高,能够强化煤基质的力学特性;高岭石松软,使煤具有软弱大变形特性。采用纳米压痕技术研究破碎煤体力学特性,具有操作方便,数据可靠和测试精确的优点。

摘要：浮选柱是细粒矿物浮选的有效设备,有着广阔的市场应用前景。研究浮选柱的数学模型,对于物料特性和操作参数已知时预测选别指标、浮选柱的设计放大及浮选过程的控制和优化有着重要意义。本文简要介绍了国内外浮选柱数学模型研究现状。

摘要：矿山用工程机械轮胎价格十分昂贵、使用周期短、更换新胎成本很高,因此需要对其进行定期维护.刺扎、污染、磨耗和速度波动较大等恶劣的工作环境,致使工程机械轮胎使用寿命缩短.对于自卸车载重轮胎来说,使用时易发生胎面脱层、胎侧刺扎、冲击破裂和胎圈损坏等问题.为了满足矿山运输要求,必须改善轮胎胎面胶配方,从而提高胎面耐磨性能.