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Intrauterine adhesions (IUA) often occur as a result of trauma to the basal layer after curettage, postpartum hemorrhage, or surgical miscarriage. Endometrial fibrosis is the primary pathological feature of IUA. The characteristic features of IUA include excessive deposition and reorganization of the extracellular matrix, replacing the normal endometrium. To prevent uterine fibrosis after injury, we prepared and evaluated a type of fibroblast suppressive hydrogel. Poly(ethylene glycol)-b-poly(l-phenylalanine) (PEBP) copolymers were successfully synthesized by ring opening polymerization of l-Phenylalanine N-carboxyanhydride, initiated by methoxy-poly(ethylene glycol)-amine. Injectable PEBP/PEG hydrogels were subsequently formed through π-π accumulations between PEBP macromolecules and hydrogen bonds among PEBP, PEG, and H2O molecules. PEBP/PEG hydrogel could suppress the proliferation of fibroblasts due to the action of l-Phe, released sustainably from PEBP/PEG gels. Lastly, the in vivo preventive effect of PEBP/PEG hydrogel on fibrosis was evaluated in a rat uterine curettage model. It was found that PEBP/PEG hydrogel suppressed uterine fibrosis caused by curettage and promoted embryo implantation in injured uterine by regulating the expression and interactions of transforming growth factor beta 1 (TGF-β1) and Muc-4. PEBP/PEG hydrogels have the potential for application in uterine adhesion prevention owing to their fibrosis preventive and pregnancy promotiing effects on uterine tissue after injury.

Intrauterine adhesions (IUA) often occur as a result of trauma to the basal layer after curettage, postpartum hemorrhage, or surgical miscarriage. Endometrial fibrosis is the primary pathological feature of IUA. The characteristic features of IUA include excessive deposition and reorganization of the extracellular matrix, replacing the normal endometrium. To prevent uterine fibrosis after injury, we prepared and evaluated a type of fibroblast suppressive hydrogel. Poly(ethylene glycol)

Two spiroannulated molecular structures with dithiafulvenyl units functionalized at the 2,2',7,7'- (SFX-DTF1) and 2,3',6,'7- (SFX-DTF2) positions of a spiro[fluorene-9,9'-xanthene] core were synthesized. Studies revealed the hole mobility was significantly influenced by the dithiafulvenyl functionalized positions in the molecular structure. To explore their primary applications as hole-transporting materials in perovskite solar cells, SFX-DTF1-based devices exhibited a power conversion efficiency of 10.67% without the use of p-type dopants, yielding good air stability.

High-performance organic photovoltaics (OPVs) are of great scientific and technological importance due to their potential large-scale industrial applications. Introducing semiconductor quantum dots has been proven to be an effective way to improve the power conversion efficiency (PCE) of OPVs. In this paper, we report a novel approach to fabricate atomically thin antimonene quantum sheets (AMQSs) possessing a uniform size (≈2.2 nm) via imidazolium ionic liquid-assisted exfoliation. In this method, the yield of AMQSs (1.1 mg mL−1) has been increased by nearly two orders of magnitude compared with that of previously reported methods. Furthermore, upon adding AMQSs into the light absorber in OPVs, the optimal device with 1.0 mg mL−1 AMQSs shows the highest PCE of 9.75%, resulting in over 25% enhancement in PCE compared to that of the reference device. It also leads to a noticeable enhancement in the short-circuit current density (Jsc) of 16.7% and the fill factor (FF) of 8.4%. The increased PCE is mainly due to the two-dimensional electronic structure of AMQSs that can enhance the light absorption, assist exciton dissociation and reduce charge recombination of OPVs. This work provides a new avenue toward mass production of two-dimensional quantum sheets and points to a new strategy for highly efficient OPVs.

Two spiro[fluorene-9,9′-xanthene]-centered (SFX), tetra-carbazole substituted molecules 2,2′,7,7′-tetrakis( N , N -carbazole)-spiro(fluorene-9,9′-xanthene) ( SFX-Cr1 ) and 2,3′,6,′7-tetrakis( N , N -carbazole)-spiro(fluorene-9,9′-xanthene) ( SFX-Cr2 ) were synthesized, and the effect of the position of carbazole substitutes on bulk properties, such as photophysical and electrochemical properties, thermal stability and hole mobility were investigated. The results implied both these two materials have excellent thermal stability and hole mobility than those of N , N ′-Bis(naphthalen-1-yl) N , N ′-bis(phenyl)-benzidine ( NPB ). To explore the application, organic light-emitting diodes (OLEDs) with SFX-Cr1 and SFX-Cr2 as hole transport layer were fabricated and characterized. SFX-Cr2 garnered the highest glass transition temperature of 130.1 °C and hole mobility of 1.57 × 10 −3 cm 2 V −1 S −1 , yielding an appreciated OLED performance in terms of a maximum current efficiency of 55.8 cd A −1 , a maximum power efficiency of 46.6 l m W −1 , and a maximum external quantum efficiency of 16.3%.

Defects passivation in electron transport layer (ETL) is a key issue to optimize the performance of polymer solar cells (PSCs). In this work, a novel strategy is developed to form defects passivated ZnO ETL by introducing 4-tert-butylpyridine (TBP) agent into precursor. While the power conversion efficiency (PCE) of the inverted PSCs based poly{4,8-bis [(2-ethylhexyl)oxy]benzo [1,2-b:4,5-b']dithiophene-2,6-diyl-alt-3-fluoro-2-[(2-ethylhexyl)carbonyl]thieno [3,4-b]thiophene-4,6-diyl}:[6,6]-phenyl C71-butyric acid methyl ester (PTB7:PC71BM) with the pure ZnO ETL is 8.02%, that of the device with modified ZnO ETL is dramatically improved to 10.26%, with TBP accounting for ~28% efficiency improvement. Our study demonstrates that the precursor agent significantly affect the surface morphology and size of ZnO in ETL. Furthermore, it proves that the ZnO ETL with TBP (T-ZnO) is beneficial to polish interfacial contact between ETL and active layer and depress exciton quenching loss, resulting in enhanced exciton dissociation, efficient carrier collection and reduced charge recombination, thus improving the device performance. To verify the universality of T-ZnO ETL, the champion photovoltaic performance with a PCE of 11.74% (10% improvement) is obtained in the PBDB-T-2F:IT-4F based nonfullerene PSCs using T-ZnO as ETL. Our work developed a new, universal and facile strategy for designing highly efficient PSCs based on fullerene and nonfullerene blend systems.

In this paper, urea-doped ZnO (U-ZnO) is investigated as a modified electron transport layer (ETL) in inverted polymer solar cells (PSCs). Using a blend of Poly{4,8-bis[(2-ethylhexyl)oxy] benzo [1,2-b:4,5-b'] dithiophene-2,6-diyl-alt-3-fluoro-2-[(2-ethylhexyl)carbonyl] thieno [3,4-b] thiophene-4,6-diyl}(PTB7), and [6,6]-phenyl-C71-butyric acid methyl ester (PC71BM) as light absorber, a champion power conversion efficiency (PCE) of 9.15% for U-ZnO ETL based PSCs was obtained, which is 15% higher than that of the pure ZnO ETL based PSCs (7.76%). It was demonstrated that urea helps to passivate defects in ZnO ETL, resulting in enhanced exciton dissociation, suppressed charge recombination and efficient charge extraction efficiency. This work suggests that the utilization of the U-ZnO ETL offer promising potential for achieving highly efficient PSCs.

Engineering product design is an information intensive decision-making process that consists of several phases including design specification definition, design concepts generation, detailed design and analysis, and manufacturing. Usually, generating geometry models for visualization is a big challenge for early stage conceptual design. Complexity of existing computer aided design packages constrains participation of people with various backgrounds in the design process. In addition, many design processes do not take advantage of the rich amount of legacy information available for new concepts creation. The research presented here explores the use of advanced graphical techniques to quickly and efficiently merge legacy information with new design concepts to rapidly create new conceptual product designs. 3D mesh metamorphosis framework ―3DMeshMorpher‖ was created to construct new models by navigating in a shape-space of registered design models. This efficient software framework enables designers to create numerous geometric concepts in real time with a simple graphical user interface. The framework is composed of: 1) a fast spherical parameterization method to map a geometric model (genus-0) onto a unit sphere; 2) a geometric feature identification and picking technique based on 3D skeleton extraction; and 3) a LOD controllable 3D remeshing scheme with spherical mesh subdivision based on our spherical parameterization. Our spherical parameterization is focused on closed genus-zero meshes. The method is based upon barycentric coordinates with convex boundary. Unlike most existing similar

Currently, new product concepts are often evaluated by developing detailed virtual part and assembly models with traditional computer aided design (CAD) tools followed by appropriate analyses (e.g., finite element analysis, computational fluid dynamics, etc.). The creation of these models and analyses are tremendously time consuming. If a number of different conceptual configurations have been determined, it may not be possible to model and analyze each of them due to the complexity of these evaluation processes. Thus, promising concepts might be eliminated based solely on insufficient time and resources for assessment. In addition, the virtual models and analyses performed are usually of much higher detail and accuracy than what is needed for such early assessment. By eliminating the time-consuming complexity of a CAD environment and incorporating qualitative assessment tools, engineers could spend more time evaluating concepts that may have been previously abandoned due to time constraints. To address these issues, the Advanced Systems Design Suite (ASDS), was created. The ASDS incorporates a PC user interface with an immersive virtual reality (VR) environment to ease the creation and assessment of conceptual design prototypes individually or collaboratively in an immersive VR environment. Assessment tools incorporate metamodeling approximations and immersive visualization to evaluate the feasibility of each concept. In this paper, the ASDS system and interface along with specifically designed immersive VR assessment tools such as state saving and dynamic viewpoint creation are presented for conceptual large vehicle design. A test case example of redesigning an airplane is presented to explore the feasibility of the proposed system.

3D mesh parameterization is widely investigated with various parameter domains and applied in many computer graphics applications. As many surface meshes are manifolds of genus zero, mapping these meshes onto a topologically equivalent sphere provides some advantages. We introduce an efficient parameterization method based on barycentric embedding for this spherical domain. This method provides an overlapping solution which emphasizes on eliminating the vertex overlappings to ensure bijectivity. Experimental results indicate that it works faster than existing spherical parameterization methods. And we also provide a robust spherical remeshing algorithm based on spherical mesh subdivision. A local recursive subdivision process is employed to cover all the geometric details from the original mesh. Such subdivision process can be controlled to match the desired level of details (LOD), which will create a group of mesh representations with different resolutions. This multi-resolution remeshing framework could benefit various graphical applications including geometry rendering, mesh simplification/refinement, model morphing and etc.

Currently, new product concepts are evaluated by developing detailed virtual models with Computer Aided Design (CAD) tools followed by evaluation analyses (e.g., finite element analysis, computational fluid dynamics, etc.). Due to the complexity of these evaluation methods, it is generally not possible to model and analyze each of the ideas generated throughout the conceptual design phase of the design process. Thus, promising ideas may be eliminated based solely on insufficient time to model and assess them. Additionally, the analysis performed is usually of much higher detail than needed for such early assessment. By eliminating the time-consuming CAD complexity, engineers could spend more time evaluating additional concepts. To address these issues, a software framework, the Advanced Systems Design Suite (ASDS), was created. The ASDS incorporates a PC user interface with an immersive virtual reality (VR) environment to ease the creation and assessment of conceptual design prototypes individually or collaboratively in a VR environment. Assessment tools incorporate metamodeling approximations and immersive visualization to evaluate the validity of each concept. In this paper, the ASDS framework and interface along with specifically designed immersive VR assessment tools such as state saving, dynamic viewpoint creation, and animation playback are presented alongside a test case example of redesigning a Boeing 777 in the conceptual design phase.Copyright © 2009 by ASME

Software packages used in the engineering design process have become increasingly complex. Computer aided design (CAD) and finite element analysis (FEA) tools are capable of generating high fidelity models and simulations that have become indispensible components of any design. However, a fair amount of experience and time is required to effectively use such software. When designing at the conceptual level, a high level of accuracy is not needed. Rapid concept generation and evaluation is the primary focus. Unfortunately, few tools exist that successfully suit these needs. The Advanced Systems Design Suite (ASDS) is an application which allows a user to quickly design 3D conceptual models and perform both qualitative and quantitative assessments. This quantitative feedback provided through the use of metamodels which, once constructed, can be evaluated in real time. In this paper, two different metamodeling techniques are applied: Polynomial Response Surface (PRS) and Polynomial Chaos Expansion (PCE). Experiments are carried out using various models in order to determine which is most suitable to a conceptual design and assessment application. Both third order PRS and PCE with second order interaction effects were found to yield positive results when generated from as few as thirty data points.

Currently, new product concepts are evaluated by developing detailed virtual part and assembly models with traditional Computer Aided Design (CAD) tools followed by appropriate analyses (e.g., finite element analysis, computational fluid dynamics, etc.). The creation of these models and analyses are tremendously time consuming. If a number of different conceptual configurations have been determined, it may not be possible to model and analyze each of them. Thus, promising concepts might be eliminated based solely on insufficient time to assess them. In addition, the virtual models and analyses performed are usually of much higher detail and accuracy than what is needed for such early assessment. By eliminating the time-consuming complexity of a CAD environment and incorporating qualitative assessment tools, engineers could spend more time evaluating additional concepts, which were previously abandoned due to time constraints. In this paper, a software framework, the Advanced Systems Design Suite (ASDS), for creating and evaluating conceptual design configurations in an immersive virtual reality environment is presented. The ASDS allows design concepts to be quickly modeled, analyzed, and visualized. It incorporates a PC user interface with an immersive virtual reality environment to ease the creation and assessment of conceptual design prototypes. The development of the modeling and assessment tools are presented along with a test case to demonstrate the usability and effectiveness of the framework.Copyright © 2007 by ASME

Micro-machined cantilevers coated with self-assembled monolayers (SAM) of alkanethiols are being utilized as sensing elements for new generation of high-sensitivity chemical and biological sensors. Presence of chemical species is detected by resolving the surface stress change associated with absorption/adsorption of analyte molecules on the sensitized cantilever. Challenges to widespread use of micromechanical cantilever sensors are: susceptibility to vibrations, integration in a single device and understanding the mechanism governing surface stress generation. In the current work, surface stress development associated with formation of self-assembled-monolayers of alkanethiols was characterized using curvature interferometry. In order to understand the molecular mechanism underlying the surface stress generation, a multi-scale model is developed to predict the surface stress generated during absorption of the alkanethiols on a gold film.

Conceptual design involves generating hundreds to thousands of concepts and combining the best of all the concepts into a single idea to move forward into detailed design. With the current tools available, design teams usually model a small number of concepts and analyze them using traditional Computer-Aided Design (CAD) analysis tools. The creation and validation of concepts using CAD packages is extremely time consuming and unfortunately, not all concepts can be evaluated. Thus, promising concepts can be eliminated based on insufficient time and resources to use the tools available. Additionally, these virtual models and analyses are usually of much higher fidelity than what is needed at such an early stage of design. To address these issues, an desktop and immersive virtual reality (VR) framework, the Advanced Systems Design Suite (ASDS), was created to foster rapid geometry creation and concept assessment using a unique creation approach which does not require precise mating and dimensioning constraints during the geometry creation phase. The ASDS system removes these precision constraints by using 3D manipulation tools to build concepts and providing a custom easy-to-use measurement system when precise measurements are required. In this paper, the ASDS framework along with a unique and intuitive measurement system are presented for large vehicle conceptual design.Copyright © 2010 by ASME