以“联合大作业”实践加强学生创新创业能力的培养

以联合大作业的实践项目,通过校企合作、项目驱动、兴趣引导、文献查阅、市场调研、实验研发等实践训练,激发学生的创新创业意识,加强课内外联动,培养学生的自主学习能力、团队协作能力和创新能力。改革实践教学模式和方法,构建产学研创新实践平台,探索符合社会转型发展需要的复合型、创新型人才课外培养的有效途径。

Vacancy defect modulation in hot-casted NiOx film for efficient inverted planar perovskite solar cells

Nickel oxide(NiOx)has exhibited great potential as an inorganic hole transport layer(HTL)in perovskite solar cells(PSCs)due to its wide optical bandgap and superior stability.In this study,we have modulated the Ni26 vacancies in NiOx film by controlling deposition temperature in a hot-casting process,resulting the change of coordination structure and charge state of NiOx.Moreover,the change of the HOMO level of NiOx makes it more compatible with perovskite to decrease energy losses and enhance hole carrier injection efficiency.Besides,the defect modulation in the electronic structure of NiOx is beneficial for increasing the electrical conductivity and mobility,which are considered to achieve the balance of charge carrier transport and avoid charge accumulation at the interface between perovskite and HTL effectively.Both experimental analyses and theoretical calculations reveal the increase of nickel vacancy defects change the electronic structure of NiOx by increasing the ratio of Ni3^+/Ni2^+-and improving the p-type characteristics.Accordingly,an optimal deposition temperature at 120℃enabled a 36.24%improvement in the power conversion efficiency compared to that deposited at room temperature(25℃).Therefore,this work provides a facile method to manipulate the electronic structure of NiOx to improve the charge carrier transport and photovoltaic performance of related PSCs.

Benzotriazole derivative inhibits nonradiative recombination and improves the UV-stability of inverted MAPbI_(3) perovskite solar cells

Suppressing the nonradiative recombination in the bulk and surface of perovskite film is highly desired to improve the power conversion efficiency(PCE)and stability of halide perovskite solar cells(PSCs).In this study,a benzotriazole derivative(6-chloro-1-hydroxybenzotriazole,Cl-HOBT)is applied to improve the crystallinity and reduce the trap density of methylammonium lead iodide(MAPbI3)perovskite film.Meanwhile,incorporation of Cl-HOBT elongates the photoluminescence carrier lifetime and chargerecombination lifetime,implying the trap-assisted nonradiative recombination is greatly suppressed.Besides,the improved energy level alignment and enhanced built-in potential are conducive to the charge carrier separation and transfer process with Cl-HOBT.Consequently,a PCE of 20.27%and an open-circuit voltage(Voc)of 1.09 V are achieved for the inverted MAPbI3 PSCs,along with an 85%maintaining of the initial PCE under stored at relative humidity of 20%for 500 h.Furthermore,the existence of Cl-HOBT could inhibit the formation of Pb0 defect under prolonged UV illumination to retard the degradation of perovskite film.It is believed that this study paves a novel path for the realization of highefficiency PSCs with UV-stability.

Hot-Casting Large-Grain Perovskite Film for Efficient Solar Cells:Film Formation and Device Performance

Organic-inorganic metal halide perovskite solar cells(PSCs) have recently been considered as one of the most competitive contenders to commercial silicon solar cells in the photovoltaic field.The deposition process of a perovskite film is one of the most critical factors affecting the quality of the film formation and the photovoltaic performance.A hot-casting technique has been widely implemented to deposit high-quality perovskite films with large grain size,uniform thickness,and preferred crystalline orientation.In this review,we first review the classical nucleation and crystal growth theory and discuss those factors affecting the hot-casted perovskite film formation.Meanwhile,the effects of the deposition parameters such as temperature,thermal annealing,precursor chemistry,and atmosphere on the preparation of high-quality perovskite films and high-efficiency PSC devices are comprehensively discussed.The excellent stability of hot-casted perovskite films and integration with scalable deposition technology are conducive to the commercialization of PSCs.Finally,some open questions and future perspectives on the maturity of this technology toward the upscaling deposition of perovskite film for related optoelectronic devices are presented.

THREE-DIMENSIONAL STATIC ANALYSES FOR FGM PLATES WITH MEDIUM COMPONENTS AND DIFFERENT NET STRUCTURES

A new microelement method for the analyses of functionally graded structures was proposed. The key of this method is the maneuverable combination of two kinds of elements. Firstly, the macro elements are divided from the functionally graded material structures by the normal finite elements. In order to reflect the functionally graded distributions of materials and the microconstitutions in each macro-element, the microelement method sets up the dense microelements in every macro-element, and translates nodes to the same as the normal finite elements by the degrees of freedom of all microelemental the compatibility conditions. This microelement method can fully reflect the micro constitutions and different components of materials, and its computational elements are the same as the normal finite elements, so it is an effective numerical method for the analyses of the functionally graded material structures. The three-dimensional analyses of functionally graded plates with medium components and different micro net structures are given by using the microelement method in this paper. The differences of the stress contour in the plane of functionally graded plates with different net microstructures are especially given in this paper.

Experimental Investigation of Boundary Layer Characteristics on Blade Surface under Different Inlet Flow Conditions

In this paper, an experimental study is conducted on cascade boundary layer under different inlet conditions. New method is used to measure the total pressure in blade surface boundary layer directly using total pressure probe. Total pressure in both suction and pressure surfaces are acquired at different inlet conditions by changing incidence angle and inlet Mach number. In addition, a series of parameters related to boundary layer characteristics are calculated. The objective of the experiment is to investigate the influence of inlet flow conditions on them. The results indicate that influence of incidence angle is significant when other conditions are the same. Displacement thickness, momentum thickness as well as other parameters display some disciplines for variation. In contrast, inlet Mach number has only a small influence in that boundary layer becomes a litter thinner with increasing Mach number. Comparisons of experimental results with theoretical expectations demonstrate that the method in this experiment is effective and reliable.

Ligand-controlled electrochemiluminescence generation from CdSe/CdS/ZnS core/shell/shell quantum dots

The CdSe/CdS/ZnS core/shell/shell quantum dots(QDs)with strong exciton confinement have manifested themselves as competitive light-emitting materials in electrochemiluminescence(ECL).However,cathodic ECL generation by these QDs requires the injection of electron and hole from solid electrode and electrogenerated radicals(for example SO_(4)•^(−)),which is inevitably influenced by not only the inorganic structure of QDs but also the organic ligands on the surface.In this work we aimed at studying the impact of surface organic ligands on ECL performance of CdSe/CdS/ZnS QDs.When changing the surface ligand from oleate to acetate,we phenomenologically observed the positive shift of ECL onset potential by ca.200 mV and the increase of ECL intensity by~100 times,suggesting that a short ligand is more favorable for ECL generation.To further comprehend the ligand effect,we measured the charge injection kinetics using potential-modulated,time-resolved photoluminescence,and thinlayer spectroelectrochemistry techniques.The electron and hole injection into QDs were found to be accelerated by 2–20 times if shortening the ligand from oleate to acetate,confirming the significant impact of surface ligands on ECL performance of QDs.The study is expected to provide guidance on how to design surface functionalized QDs for specific applications such as ECL immunodiagnosis,photocatalysis,and photovoltaics.

通过USP7结合分子胶上调P53蛋白

Molecular glues are typically small chemical molecules that act at the interface between a target protein and degradation machinery to trigger ternary complex formation.Identifying molecular glues is challenging.There is a scarcity of target-specific upregulating molecular glues,which are highly anticipated for numerous targets,including P53.P53 is degraded in proteasomes through polyubiquitination by specific E3 ligases,whereas deubiquitinases(DUBs)remove polyubiquitination conjugates to counteract these E3ligases.Thus,small-molecular glues that enhance P53 anchoring to DUBs may stabilize P53 through deubiquitination.Here,using small-molecule microarray-based technology and unbiased screening,we identified three potential molecular glues that may tether P53 to the DUB,USP7,and elevate the P53 level.Among the molecular glues,bromocriptine(BC)is an FDA-approved drug with the most robust effects.BC was further verified to increase P53 stability via the predicted molecular glue mechanism engaging USP7.Consistent with P53 upregulation in cancer cells,BC was shown to inhibit the proliferation of cancer cells in vitro and suppress tumor growth in a xenograft model.In summary,we established a potential screening platform and identified potential molecular glues upregulating P53.Similar strategies could be applied to the identification of other types of molecular glues that may benefit drug discovery and chemical biology studies.

Imaging Analysis Based on Electrogenerated Chemiluminescence

Electrochemiluminescence(ECL),also called electrogenerated chemiluminescence,is luminescence that is produced by chemical reactions triggered by electrochemical method.ECL imaging is a novel imaging technique,which can simultaneously provide two kinds of signals of both electrochemistry and optical image.Over the past two decades,ECL imaging has been not only a powerful tool for investigating the fundamental scientific questions such as ECL mechanisms and reaction kinetics,but also a versatile analytical technique for detection of a wide range of analytes including small molecules,DNA,proteins,and cells.In the first part of this review,we briefly describe the reaction mechanisms of ECL generation.Then the review focuses on the research progress on the ECL imaging approach.It is basically introduced from the following five aspects:(i)visualization of electroactive sites on surfaces,(ii)imaging analysis at the single-bead and single-cell levels,(iii)array bioanalysis,(iv)multi-color ECL imaging,and(v)paper chip based on ECL imaging.Finally,some perspectives and future directions in this active research area are presented.

Comparison of aerodynamic characteristics between a novel highly loaded injected blade with curvature induced pressure-recovery concept and one with conventional design

This paper introduces a novel design method of highly loaded compressor blades with air injection.CFD methods were firstly validated with existing data and then used to develop and investigate the new method based on a compressor cascade.A compressor blade is designed with a curvature induced pressure-recovery concept.A rapid drop of the local curvature on the blade suction surface results in a sudden increase in the local pressure,which is referred to as a curvature induced ‘Shock＇.An injection slot downstream from the ‘Shock＇ is used to prevent ‘Shock＇ induced separation,thus reducing the loss.As a result,the compressor blade achieves high loading with acceptable loss.First,the design concept based on a 2D compressor blade profile is introduced.Then,a 3D cascade model is investigated with uniform air injection along the span.The effects of the incidence are also investigated on emphasis in the current study.The mid-span flow field of the 3D injected cascade shows excellent agreement with the 2D designed flow field.For the highly loaded cascade without injection,the flow separates immediately downstream from the ‘Shock＇;the initial location of separation shows little change in a large incidence range.Thus air injection with the same injection configuration effectively removes the flow separation downstream from the curvature induced ‘Shock＇ and reduces the size of the separation zone at different incidences.Near the endwall,the flow within the incoming passage vortex mixes with the injected flow.As a result,the size of the passage vortex reduces significantly downstream from the injection slot.After air injection,the loss coefficient along spanwise reduces significantly and the flow turning angle increases.