摘要：肿瘤微环境中的血管生成是肿瘤细胞对放化疗不敏感的主要原因.在本项研究中,我们设计了一种微环境响应型的纳米颗粒,利用ZrMOF的分解产物抑制肿瘤细胞中的PI3K/AKT/mTOR/VEGF通路,从而克服A549R细胞对顺铂的耐药性.我们将顺铂包裹在Zr-MOF中,并在表面修饰BSA,形成了CDDP@Zr-MOF-BSA纳米复合体,该复合体在肿瘤微环境中有良好的响应性,有助于在肿瘤区域蓄积,展现出卓越的血管生成抑制能力,并能明显降低药物的外排.此外,CDDP@Zr-MOFBSA能显著抑制多药耐药相关蛋白1(MRP1)的表达,从而逆转A549R细胞的耐药性.总体而言,CDDP@Zr-MOF-BSA对A549R有细胞毒性,能抑制肿瘤微环境中的血管生成,最终有效提高顺铂耐药肿瘤的治疗效果.CDDP@Zr-MOF-BSA为放化疗治疗耐药肿瘤提供了一种多功能协同的方法.

摘要：As a brazing foil, 4004 A1 alloy has good welding performance. However, the high Si content decreases the plasticity of the alloy. In order to improve the plasticity of 4004 A1 alloy and subsequently improve the productivity of 4004 AI foil, 4004 A1 alloy was modified by RE-Ba-Sb. As a comparison, the 4004 A1 alloy was also modified by RE with different addition. The tensile properties of the alloy reach the best when the addition of RE was 0.2%, in which the tensile strength and elongation were 194 MPa and 5%, respectively. For RE-Ba-Sb modification, the addition of three elements was optimized by orthogonal analysis. The results showed that the greatest impact parameter of RE-Ba-Sb modification was RE addition, followed by addition of Ba and Sb. The optimum addition amounts of RE, Ba and Sb obtained by orthogonal analyses were 0.01%, 0.3%, and 0.05%, respectively. The tensile strength and the elongation of 4004 A1 alloy modified by the optimal modification process were 224 MPa and 6%, respectively. The amount of RE addition in RE-Ba-Sb modification is lower than that in RE modification.

摘要：There is a relatively complex flow state inside the high speed on-off valve,which often produces low pressure area and oil reflux in the high-speed opening and closing process of the spool,causing cavitation and vortex and other *** phenomena will affect the stability of the internal flow field of the plate valve and the flow characteristics of the high speed on-off *** at the problems of small flow rate and instability of internal flow field,a new spool structure was *** flow field models of two-hole and three-hole plate spools with different openings were established,and software ANSYS Workbench was chosen to mesh the *** standard k−εturbulence model was selected for numerical simulation using FLUENT *** pressure distribution and velocity distribution under the same pressure and different opening degree were *** structure and parameters of the optimization model were also *** stability analysis of flow field under different pressure was carried *** results demonstrate that the three-hole spool has a similar flow field change with the two-hole spool,but it does not create a low pressure zone,and the three-hole spool can work stably at 2 MPa or *** method improves the appearance of low pressure area and oil backflow in the process of high speed opening and closing of *** stability of flow field and the flow rate of high speed switch valve are ***,the products designed in this paper are compared with existing hydraulic valve *** results show that the three-hole plate type high speed on-off valve designed in this paper maintains the stability of the internal flow field under the condition of 200 Hz and large opening degree,and realizes the increase of flow rate.

摘要：The H_∞ performance analysis and controller design for linear networked control systems(NCSs) are *** NCSs are considered a linear continuous system with time-varying interval input delay by assuming that the sensor is time-driven and the logic Zero-order-holder(ZOH) and controller are *** on this model,the delay interval is divided into two equal subintervals for H_∞ performance *** improved H_∞ stabilization condition is obtained in linear matrix inequalities(LMIs) framework by adequately considering the information about the bounds of the input delay to construct novel Lyapunov–Krasovskii functionals(LKFs).For the purpose of reducing the conservatism of the proposed results,the bounds of the LKFs differential cross terms are properly estimated without introducing any slack matrix ***,the H_∞ controller is reasonably designed to guarantee the robust asymptotic stability for the linear NCSs with an H_∞ performance level γ.Numerical simulation examples are included to validate the reduced conservatism and effectiveness of our proposed method.

摘要：The development of effective and low-cost catalysts for overall water splitting is essential for clean production of hydrogen from *** this paper,we report the synthesis of cobalt-vanadium（Co-V）bimetal-based catalysts for the effective water *** Co_2V_2O_7·xH_2O nanoplates containing both Co and V elements were selected as the *** the calcination under NH_3atmosphere,the Co_2VO_4and Co/VN could be obtained just by tuning the calcination *** tests indicated that the Co-V bimetal-based materials could be used as active hydrogen evolution reaction（HER）and oxygen evolution reaction（OER）catalyst by regulating their *** Co/VN showed good performance for HER with the onset potential of68 mV and can achieve a current density of 10 mA cm^（-2）at an overpotential of 92 m ***,the Co_2VO_4exhibited the obvious OER performance with overpotential of 300 mV to achieve a current density of 10 mA cm^（-2）.When the Co_2VO_4and Co/VN were used as the anode and cathode in a twoelectrode system,respectively,the cell needed a voltage of1.65 V to achieve 10 mA cm^（-2）together with good *** work would be indicative to constructing Co-V bimetalbased catalysts for the catalytic application.

摘要：One of the reasons behind failed engineering surfaces and mechanical components is particle erosion wear;thus,to mitigate its happening,biomimetic engineering is the current state-of-the-art being ***,this paper reviews the literature and the development trends on erosive wear resistance that employ biomimetic methods as well as analyze the bio-inspired surface,the bio-inspired structure,the bio-based materials,the associated challenges,and the future ***,the feasibility of the multi-biological and perspective on the coupling biomimetic method for anti-erosion wear are *** is concluded that the design of anti-erosion materials or structures by the bio-inspired methods is of great significance in the development of engineering applications.

摘要：Mobile cloud computing （MCC） has become a promising technique to deal with computation- or data-intensive tasks. It overcomes the limited processing power, poor storage capacity, and short battery life of mobile devices. Providing continuous and on-demand services, MCC argues that the service must be available for users at anytime and anywhere. However, at present, the service availability of MCC is usually measured by some certain metrics of a real-world system, and the results do not have broad representation since different systems have different load levels, different deployments, and many other random factors. Meanwhile, for large-scale and complex types of services in MCC systems, simulation-based methods （such as Monte- Carlo simulation） may be costly and the traditional state-based methods always suffer from the problem of state-space explosion. In this paper, to overcome these shortcomings, fluid-flow approximation, a breakthrough to avoid state-space explosion, is adopted to analyze the service availability of MCC. Four critical metrics, including response time of service, minimum sensing time of devices, minimum number of nodes chosen, and action throughput, are def＇med to estimate the availability by solving a group of ordinary differential equations even before the MCC system is fully deployed. Experimental results show that our method costs less time in analyzing the service availability of MCC than the Markov- or simulation-based methods.

摘要：Development of cost-effective,active and durable electrocatalysts for overall water splitting is still a huge ***,we have constructed one-dimensional(1D)cobalt sulfide and vanadium sulfide heterojunction nanowires arranged on carbon cloth(Co_(9)S_(8)-V_(3)S_(4)/CC)as bifunctional electrocatalysts for the efficient overall water *** 1D wire-structured Co_(9)S_(8)-V_(3)S_(4)heterojunctions possess large surface area,plentiful active sites and rapid transport of electrons/reactants and the release of ***,the electron transfer from Co9S8 to V3S4 occurs at the interface due to the strong electronic coupling effect in Co_(9)S_(8)-V_(3)S_(4)heterojunction,in which the electron-attracting V3S4(V2^(+))optimizes the adsorption of H*active species for hydrogen evolution reaction(HER),while the electron-losing Co9S8(Co3+)responds to the enhancement of oxygen evolution reaction(OER)***_(9)S_(8)-V_(3)S_(4)/CC exhibits low overpotentials of 85 and 232 mV at 10 mA cm^(−2)and small Tafel slopes of 51 and 59 mV dec^(−1)for HER and OER,***,the electrolyzer with Co_(9)S_(8)-V_(3)S_(4)/CC as both the anode and cathode requires low onset voltage of 1.35 V and cell voltage of 1.53 V at 10 mA cm^(−2)and exhibits high Faradaic efficiencies and robust *** can be driven by a solar cell(1.53 V)for continuous production of hydrogen and *** study highlights the design of 1D sulfide heterojunction in pursuit of highly efficient electrocatalysts for overall water splitting.

摘要：TiO2-NaYF4：Er^3＋/Yb^3＋-C3N4 composite photoanodes were successfully designed for the first time. The photoelectric conversion efficiency of TiO2-NaYF4：Er^3＋/Yb^3＋ C3N4 composite cell can result an efficiency of 7.37%, which is higher than those of pure TiO2 cell and TiO2-C3N4 composite cell. The enhancement of the efficiency can be attributed to the synergetic effect of NaYF4：Er^3＋/Yb^3＋ and C3N4. Elec- trochemical impedance spectroscopy analysis revealed that the interfacial resistance of the TiO2-dyelI3^-/I^- electrolyte interface of TiO2-NaYF4：Er^3＋/Yb^3＋-C3N4 composites cell was much smaller than that of pure TiO2 cell. In addition, the TiO2-NaYF4：Er^3＋/Yb^3＋-C3N4 composite cell had longer electron recombination time and shorter electron transport time than that of pure TiO2 cell.

摘要：In order to propel the development of metal magnetic memory （MMM） technique in fatigue damage detection, the Jiles-Atherton model （J-A model） was modified to describe MMM mechanism in elastic stress stage. A series of rotating bending fatigue experiments were conducted to study the stress-magnetization relationship and verify the correctness of modified J-A model. In MMM detection, the magnetization of material irreversibly approaches to the local equilibrium state Mo instead of global equilibrium state M^n under cyclic stress, and the M0-a curves are loops around the Mar,-a curve. The modified J-A model is constructed by replacing M~ in J-A model with M0, and it can describe the magnetomechanical effect well at low external magnetic field. In the rotating bending fatigue experiments, the MMM field distribution in normal direction around cylinder specimen is similar to the stress distribution, and the calculation result of model coincides with experiment result after some necessary modifications. The MMM field variation with time at a certain point in fatigue process is divided into three stages with the variation of stable stress-stain hysteresis loop, and the calculation results of model can explain not only the three stages of MMM field changes, but also the different change laws when the applied magnetic field and initial magnetic field are different. The MMM field distribution in normal direction along specimen axis reflects stress concentration effect at artificial defect, and the magnetic signal fluctuates around the defect at late fatigue stage. The calculation results coincide with the initial MMM principle and can explain signal fluctuates around the defect. The modified J-A model can explain experiment results well, and it is fit for MMM field characterization.