摘要：Network design problems （NDPs） have long been regarded as one of the most challenging problems in the field of transportation planning due to the intrinsic non-convexity of their bi-level programming form. Furthermore, a mixture of continuous/discrete decision variables makes the mixed network design problem （MNDP） more complicated and difficult to solve. We adopt a surrogate-based optimization （SBO） framework to solve three featured categories of NDPs （continuous, discrete, and mixed-integer）. We prove that the method is asymptotically completely convergent when solving continuous NDPs, guaranteeing a global optimum with probability one through an indefinitely long run. To demonstrate the practical performance of the proposed framework, numerical examples are provided to compare SBO with some existing solving algorithms and other heuristics in the literature for NDP. The results show that SBO is one of the best algorithms in terms of both accuracy and efficiency, and it is efficient for solving large-scale problems with more than 20 decision variables. The SBO approach presented in this paper is a general algorithm of solving other optimization problems in the transportation field.

摘要：Currently,osteochondral(OC)tissue engineering has become a potential treatment strategy in repairing chondral lesions and early osteoarthritis due to the limited self-healing ability of ***,it is still challenging to ensure the integrity,physiological function and regeneration ability of stratified OC scaffolds in clinical *** OC scaffolds are attractive to overcome the above problems because of their similar biological and mechanical properties with native OC *** a consequence,the researches on biomimetic design to achieve the tissue function of each layer,and additive manufacture(AM)to accomplish composition switch and ultrastructure of personalized OC scaffolds have made a remarkable *** this review,the design methods of biomaterial and structure as well as computer-aided design,and performance prediction of biopolymer-based OC scaffolds are presented;then,the characteristics and limitations of AM technologies and the integrated manufacture schemes in OC tissue engineering are summarized;finally,the novel biomaterials and techniques and the inevitable trends of multifunctional bio-manufacturing system are discussed for further optimizing production of tissue engineering OC scaffolds.

摘要：A flow control method based on an active jet is developed to restart hypersonic inlets. The dynamic restarting process is numerically reproduced by unsteady Reynolds averaged Navier-Stokes(RANS) modeling to verify the effectiveness and reveal the influence of jet conditions. The active jet improves the inlet unstart status by drawing the high-pressure separation bubble from the internal compression duct and performing a full expansion to alleviate the adverse pressure gradient. Moreover, the favorable pressure gradient in the inlet caused by jet expansion allows for a successful restart after turning off the jet. The influence of the jet momentum ratio is then analyzed to guide the design of the active jet control method and choose the proper momentum ratios. A low jet momentum does not eliminate the high-pressure separation bubble, whereas an excessive jet momentum causes severe momentum loss due to the induced shock. The general rule in restarting the inlet using an active jet is to allow a full jet expansion downstream of the jet slot while avoiding excessive momentum loss upstream and preventing the thick low-speed layer.

摘要：Intelligent structures like zero Poisson’s ratio(ZPR)cellular structures have been widely applied to the engineering fields such as morphing wings in recent decades,owing to their outstanding characteristics including light weight and low effective modulus. In-plane and out-of-plane mechanical properties of ZPR cellular structures are investigated in this paper. A theoretical method for calculating in-plane tensile modulus,in-plane shear modulus and out-of-plane bending modulus of ZPR cellular structures is proposed,and the impacts of the unit cell geometrical configurations on in-plane tensile modulus,in-plane shear modulus and out-of-plane bending modulus are studied systematically based on finite element(FE)simulation. Experimental tests validate the feasibility and effectiveness of the theoretical and FE analysis. And the results show that the in-plane and out-of-plane mechanical properties of ZPR cellular structures can be manipulated by designing cell geometrical parameters.

摘要：An efficient photocatalytic CO_(2) reduction has been reported in ZIF-67-derived-Co nanoparticles(NPs)encapsulated in nitrogen-doped carbon layers(N-C/Co).This work demonstrates that the pyrolysis temperature is crucial in tuning the grain size and components of metallic Co^(0) of N-C/Co composite catalysts,which optimizes their photocatalytic *** were conducted at 600,700,and 800℃ giving the N-C/Co-600,N-C/Co-700,and N-C/Co-800 samples,respectively.N-C layers can well wrap the Co NPs obtained at a low pyrolysis temperature(600℃)owing to their smaller grains than those of other samples.A high metallic Co^(0) content in the N-C/Co-600 sample can be attributed to the effective inhibition of surface *** contrast,the surface CoOx oxides in the N-C/Co-700 and N-C/Co-800 samples cover inside Co cores,inhibiting charge separation and *** a result,the N-C/Co-600 sample yields the best photocatalytic *** carbon monoxide and hydrogen generation rates are as high as 1.62×10^(4) and 2.01×10^(4)μmol g^(−1)h^(−1),***,the Co NPs make composite catalysts magnetic,enabling rapid and facile recovery of catalysts with the assistance of an external magnetic *** work is expected to provide an instructive guideline for designing metal-organic framework-derived carbon/metal composite catalysts.

摘要：Three-dimensional(3 D)gravitational and magnetic exploration is performed using aerial measurement tools,however,this has difficulties with measuring-height design and the construction of a joint-interpretation *** present,the height in such experiments is set according to the measurement scale,and the distribution characteristics of anomalies are not fully ***,we present the idea of using the attenuation characteristics of a singular-value spectrum to evaluate the contributions of various measurement heights and multi-height combinations for inversion to correctly and reasonably design appropriate measuring heights and the number of various measurement heights to be *** jointgradient Euler-deconvolution method can accurately obtain the distribution of geological bodies from 3 D gravitational and magnetic data at an improved resolution,and experimental tests confirm these ***,an actual 3 D aeromagnetic-data-acquisition and inversion test were carried out in the vicinity of the Zhurihe Iron Mine in Inner *** fl ight-height diff erence was set to 60 m,and the specifi c distribution of lodes was obtained by the joint-gradient Euler-deconvolution *** provides a reliable basis for future detailed exploration and proves that the methods presented in this paper have good practicalapplication eff ects and prospects.

摘要：Compared to the traditional lumped-parameter model, computational fluid dynamics （CFD） attracted more attentions due to facilitating more accurate reactor design and optimization methods when analyzing the heat transfer in the industrial packed bed. Here, a model was developed based on the CFD theory, in which the heterogeneous fluid flow was resolved by considering the oscillatory behavior of voidage and the effective fluid viscosity. The energy transports in packed bed were calculated by the convection and diffusion incorporated with gaseous dispersion in fluid and the contacting thermal conductivity of packed particles in solids. The heat transfer coefficient between fluid and wall was evaluated by considering the turbulence due to the packed particles adjacent to the wall. Thus, the heat transfer in padded bed can be predicted without using any adjustable semi-empirical effective thermal conductivity coefficient. The experimental results from the literature were employed to validate this model.

摘要：Recently, the power conversion efficiencies(PCEs) of all-polymer solar cells(all-PSCs) have increased rapidly. To further increase the PCE of all-PSCs, it is necessary to create new donor polymers matching the polymer acceptors. In this paper, we synthesize a new quinoxaline-based polymer donor PBQ8 with n-octyl side chain on the quinoxaline unit, which possesses the same skeleton structure to the previously reported PBQ5(with isooctyl side chain). The effects of alkyl side chains on the physicochemical properties of the polymer donor were investigated. In comparison with PBQ5, PBQ8 exhibits stronger intermolecular interactions and better molecular packing. When blending with polymer acceptor PY-IT, the PBQ8:PY-IT based devices demonstrated a higher PCE value of 17.04%, which is one of the highest PCEs occurred in the all-PSCs. And the PBQ5:PY-IT(PCE 15.56%, Voc0.907 V, FF 69.72%, and Jsc24.60 m A cm^(-2)) is much lower. The PBQ8:PY-IT blend displayed more efficient exciton dissociation, better molecular stacking properties, preferable phase separation and higher mobility. These indicate that as an effective method, side chain engineering can improve the efficiency of the all-PSCs.

摘要：Biomedical field has been seeking a feasible standard drug screening system consisting of 3D tumor model array for drug researching due to providing sufficient samples and simulating actual in vivo tumor growth situation,which is still a challenge to rapidly and uniformly establish ***,we propose a novel drug screening system,namely 3D tumor array chip with“layer cake”structure,for drug *** gelatin methacryloyl hydrogel droplets(~0.1μL)containing tumor cells can be automatically deposited on demand with electrohydrodynamic 3D *** conductive membrane is introduced as a chip basement for preventing charges accumulation during fabricating and convenient observing during *** chambers formed by stainless steel and silicon interlayer is convenient to be assembled and *** this chip is compatible with the existing 96-well culturing plate,the drug screening protocols could keep the same as *** properties of this chip,namely printing stability,customizability,accuracy,microenvironment,tumor functionalization,are detailly *** a demonstration,it is applied for screening of epirubicin and paclitaxel with breast tumor cells to confirm the compatibility of the proposed screening system with the traditional screening *** believe this chip will potentially play a significant role in drug evaluation in the future.

摘要：Photocatalytic hydrogen production coupled with selective oxidation of organic substrates to produce highvalue-added fine chemicals has drawn increasing ***,we report a noble metal-free photocatalyst for the highly efficient and simultaneous generation of hydrogen and the selective oxidation of benzyl alcohol into benzaldehyde over Cd S@Mo S2 heterostructures under visible *** the need for a sacrificial agent,Cd S@Mo S2 displayed an excellent hydrogen production rate of 4233μmol g^-1h^-1with0.3 mmol benzyl alcohol,which is approximately 53 times higher than that of bare Cd S nanorods(80μmol g^-1h^-1).The reaction system was highly selective for the oxidation of benzyl alcohol into *** the amount of benzyl alcohol increased to 1.0 mmol,the hydrogen production reached9033μmol g^-1h^-*** electron microscopy and transmission electron microscopy images revealed that p-type Mo S2 sheets with a flower-like structure closely adhered to n-type semiconductor Cd S nanorods through the formation of a p-n *** a potential Z-scheme photocatalyst,the Cd S@Mo S2 heterostructure effectively produces and separates electron-hole pairs under visible ***,the electrons are used for reduction to generate hydrogen,and the holes oxidize benzyl alcohol into ***,a mechanism of photogenerated charge transfer and separation was proposed and verified by photoluminescence,electrochemical impedance spectroscopy,photocurrent and Mott-Schottky *** results reveal that the Cd S@Mo S2 heterojunctions have rapid and efficient charge separation and transfer,thereby greatly improving benzyl alcohol *** work provides insight into the rational design of high-performance Z-scheme photocatalysts and the use of holes and electrons to obtain two valuable chemicals simultaneously.