摘要：Ni/TiO_(2) catalyst is widely employed for photo-driven DRM reaction while the influence of crystal structure of TiO_(2) remains *** this work,the rutile/anatase ratio in supports was successfully controlled by varying the calcination temperature of anatase-TiO_(2).Structural characterizations revealed that a distinct TiO_(x) coating on the Ni nanoparticles(NPs)was evident for Ni/TiO_(2)-700 catalyst due to strong metal-support *** is observed that the TiOx overlayer gradually disappeared as the ratio of rutile/anatase increased,thereby enhancing the exposure of Ni active *** exposed Ni sites enhanced visible light absorption and boosted the dissociation capability of CH4,which led to the much elevated catalytic activity for Ni/TiO_(2)-950 in which rutile ***,the catalytic activity of solar-driven DRM reaction was significantly influenced by the rutile/anatase ***/TiO_(2)-950,characterized by a predominant rutile phase,exhibited the highest DRM reactivity,with remarkable H2 and CO production rates reaching as high as 87.4 and 220.2 mmol/(g·h),*** rates were approximately 257 and 130 times higher,respectively,compared to those obtained on Ni/TiO_(2)-700 with *** study suggests that the optimization of crystal structure of TiO_(2) support can effectively enhance the performance of photothermal DRM reaction.

摘要：聚合物基固态电解质得益于其易加工性,最有希望应用于下一代固态锂金属电池.目前,聚合物基态电解质的离子电导率提升策略多为加入导锂陶瓷以构建离子传输通道,其提升程度有限.电场在锂离子输运过程中存在重要影响,目前研究中有关电场对锂离子传输的影响机制尚不明确.本文将兼具高离子电导率和高介电常数的铌酸锂嵌入聚偏氟乙烯基体中,设计了一种新型复合固态电解质.铌酸锂颗粒有效调节电解质内部电场结构,增强了离子输运方向电场强度,实现了离子电导率的大幅提升(7.39×10^(-4)S cm^(-1),25℃).该电解质匹配高镍正极和锂金属负极的固态电池可稳定循环1000次以上,容量保持率为72%.该研究为设计下一代固态锂电池用高离子电导复合固态电解质提供了新的策略.

摘要：过渡金属磷化物是电催化设计中的新兴材料,而多元金属磷化物因其能显著提高电催化活性而备受关注.然而,由于不同种类金属前驱物之间水解和缩合速率的差异,当前有关超过两种金属元素和化学计量比精确控制的多元金属磷化物的报道非常少.因此,合理设计多元金属磷化物的组成对提高其催化性能具有重要意义.本工作通过直接磷化二价过渡金属离子氢氧化物的合成策略,制备了能够精确控制化学计量比(x:y:z=(1–10):(1–10):1)的分级结构Co_(x)Ni_(y)Fe_(z)P,其中具有最优组分的Co_(1.3)Ni_(0.5)Fe_(0.2)P在析氧反应(OER)中展示了优异的催化活性和高稳定性.密度泛函理论计算表明,相对于其他组分的过渡金属磷化物,Co_(1.3)Ni_(0.5)Fe_(0.2)P在费米能级附近的态密度明显增加,这可以增强催化剂对OH−的吸附,从而提升OER性能.

摘要：使用液态碳氢化合物燃料的固体氧化物燃料电池(SOFCs)的商业化极大地受到阳极易积碳的阻碍.调控碳氢燃料重整反应位点的局域蒸汽/碳比以提高抗积碳性能是有效的,但仍面临挑战.本文报道了一种新型二氧化铈基催化剂(Ce_(0.95)Ru_(0.05)O_(2-δ),CR5O)的理性设计.催化剂在实际应用过程中,表现出优异的抗积碳性能.在电池运行条件下,催化剂CR5O被还原为二氧化铈骨架及镶嵌在骨架表面的Ru纳米颗粒(Ru/Ce_(0.95)Ru_(0.05)O_(2)-δ,Ru/CR5-xO).Ru/CR5-xO表现出优异的自水合能力,可以有效去除催化剂表面产生的积碳.当应用于以液态碳氢化合物为燃料的SOFCs时,电池表现出优异的电化学性能:在750℃下,以甲醇为燃料时,电池的峰值功率密度达到1.010W cm^(-2),并且在稳定运行的200h以内,没有明显积碳现象.此外,密度泛函理论计算表明,Ru/CR5-xO催化剂修饰的Ni-YSZ阳极的高活性和抗积碳性能归因于速率限制步骤的能垒降低和用于快速除碳的COH中间体的形成.

摘要：Porous titanium(Ti)scaffolds have been extensively utilized as bone substitute scaffolds due to their superior biocompatibility and excellent mechanical ***,naturally formed TiO2 on the surface limits fast *** biomolecules have been widely utilized to overcome this issue;however,homogeneous porous Ti scaffolds could not simultaneously deliver multiple biomolecules that have different release *** this study,functionally graded porous Ti scaffolds(FGPTs)with dense inner and porous outer parts were fabricated using a two-body combination and densification *** with growth factor(BMP-2)and antibiotics(TCH)exhibited suitable mechanical properties as bone substituting material and presented good structural *** release of BMP-2 was considerably prolonged,whereas the release of TCH was comparable to that of homogenous porous titanium scaffolds(control group).The osteogenic differentiation obtained using FGPTs was maintained due to the prolonged release of *** antimicrobial properties of these scaffolds were verified using *** in terms of prior release *** addition,various candidates for graded porous Ti scaffolds with altered pore characteristics were presented.

摘要：Metal organic chemical vapor deposition(MOCVD) is a key equipment in the manufacturing of semiconductor optoelectronic devices and microwave devices in industry. Heating system is a vital part of MOCVD. Specific heating device and thermal control technology are needed for each new reactor design. By using resistance-wire heating MOCVD reaction chamber model, thermal analysis and structure optimization of the reactor were developed from the vertical position and the distance between coils of the resistance-wire heater. It is indicated that, within a certain range, the average temperature of the graphite susceptor varies linearly with the vertical distance of heater to susceptor, and with the changed distances between the coils; furthermore, single resistance-wire heater should be placed loosely in the internal and tightly in the external. The modulate accuracy of the temperature field approximately equals the change of the average temperature corresponding to the change of the coil position.

摘要：设计了一个采用内点算法的灰狼优化程序以纠错天线阵列。若单个传感器故障,整个阵列辐射功率图在旁瓣电平(sidelobe level,SLL)和深零度电平(nulldepthlevel,NDL)方向受干扰,零点被破坏并发生偏离。可通过设计新的适应函数解决这些问题,并减小预期辐射功率图与零限值之间的偏差。该混合算法用于控制天线阵列的辐射功率图。仿真实验使用了由21个传感器组成的天线阵列。仿真结果表明,与现有的SLL和NDL方法相比,所提方法具有良好性能。

摘要：零热膨胀合金在精密控制工程中具有独特的应用.然而,实现零热膨胀的苛刻条件,即自旋、晶格和电荷之间存在的适当耦合,使得零热膨胀合金的种类稀少.在这项工作中,我们报告了一种在体积表现为正热膨胀合金中,通过调节晶体学取向和磁体积效应来实现二维零热膨胀行为的途径.基于此,我们在MnFe4Si3中获得了宽温度区间(10-310 K)的具有热膨胀系数α_(1)=0.45×10^(-7)K^(-1)的二维零热膨胀合金.同步加速器X射线衍射、中子衍射、电镜和磁性测试的结果表明,这种零热膨胀行为由6g位置上的Fe在a-b面内的磁矩以及块体织构共同决定.此外,Mn_(1.5)Fe_(3.5)Si_(3)和Mn_(2)Fe_(3)Si_(3)化合物表现出混磁性和负热膨胀行为,这起源于Fe_(4d)-Fe_(6g)(J_(FM))铁磁性和Mn_(4d)-Mn_(6g)(J_(AFM))反铁磁性相互作用之间的竞争.这种方法能够扩展到其他磁性或铁电材料中,以设计新的低膨胀或负膨胀块体材料.

摘要：The optimization of the scaffolds to provide a suitable matrix and accelerate the regeneration process is vital for bone tissue ***,poor mechanical and biological characteristics remain the primary challenges that must be *** example,although bredigite(Br)has shown great potential for application in bone tissue engineering,it easily fails in *** the present work,these challenges are addressed by reinforcing the Br matrix with nanosheets of graphene oxide(rGO)that have been reduced by bovine serum albumin(BSA)in order to enhance the mechanical properties and biological *** reduction of graphene oxide by BSA improves the water stability of the nanosheets and provides an electrostatic interaction between theBSA-rGO nanosheets and theBr *** high thermal conductivity of theBSA-rGO nanosheets decreases the porosity of the Br by transferring heat to the core of the ***,the addition of BSA-rGO nanosheets into the Br matrix enhances the adhesion of G-292 cells on the surface of the *** findings suggest that the tablet consisting of BSA-rGO-reinforced Br has encouraging potential for application in bone tissue engineering.

摘要：VC强化的硬质材料,如高钒高速钢(HVHSS)因高的硬度和强度,不适合低成本加工成复杂形状。研究利用60%高固含量的打印浆料通过3D凝胶打印技术(3DGP)打印HVHSS零件。通过打印参数优化,打印试样的表面质量好,可观察到明显的打印线。挤出丝原位固化后,其强度足以维持设计的形状。烧结后,试样均匀收缩,收缩率为15%,相对密度达到99%,其表面粗糙度由6.5μm降低至3.8μm。烧结试样具有致密的显微组织和细的碳化物。此外,烧结试样具有优良的综合性能,硬度为HRC 60,抗弯强度为3000 MPa,冲击功为20~26 J。本文提出的方法可用于直接制备复杂形状的硬质材料,省去了后续加工。