bluuebunny/crossref_metadata_2025_split huggingface dataset:
High Lubricity Meets Load Capacity: Cartilage Mimicking Bilayer Structure by Brushing Up Stiff Hydrogels from Subsurface
Authors: Rong Mingming , Liu Hui , Scaraggi Michele , Bai Yanyan , Bao Luyao , Ma Shuanhong , Ma Zhengfeng , Cai Meirong , Dini Daniele , Zhou Feng 
Published: August 2020

AbstractNatural articular cartilage has ultralow friction even at high squeezing pressure. Biomimicking cartilage with soft materials has been and remains a grand challenge in the fields of materials science and engineering. Inspired by the unique structural features of the articular cartilage, as well as by its remarkable lubrication mechanisms dictated by the properties of the superficial layers, a novel archetype of cartilage‐mimicking bilayer material by robustly entangling thick hydrophilic polyelectrolyte brushes into the subsurface of a stiff hydrogel substrate is developed. The topmost soft polymer layer provides effective aqueous lubrication, whereas the stiffer hydrogel layer used as a substrate delivers the load‐bearing capacity. Their synergy is capable of attaining low friction coefficients (order 0.010) under heavily loaded conditions (order 10 MPa contact pressure) in water environment, a performance incredibly close to that of natural articular cartilage. The bioinspired material can maintain low friction even when subjected to 50k reciprocating cycles under high contact pressure, with almost no wear observed on the sliding track. These findings are theoretically explained and compounded by multiscale simulations used to shed light on the mechanisms responsible for this remarkable performance. This work opens innovative technology routes for developing cartilage‐mimicking ultralow friction soft materials.
Modular Design of Supramolecular Organic Frameworks for Image‐Guided Photodynamic Therapy
Authors: Wang Wenjing , Qi Bin , Yu Xiang , Li Wen‐Zhen , Yang Zhonghua , Zhang Haibo , Liu Simin , Liu Yi , Wang Xiao‐Qiang 
Published: August 2020

AbstractInspired by the efficient modular design of contemporary engineering, a design philosophy is proposed for the construction of molecular building blocks. Here, modular design of supramolecular organic frameworks (SOFs) for image‐guided photodynamic therapy (PDT) in vivo is presented. The closo‐dodecaborate cluster (B12) can selectively bind with the convex exterior of cucurbit[8]uril (CB[8]) with a molar ratio of 1:3 through chaotropic effect, which enables the CB[8]‐B12 based SOFs with exchangeable units/functions. After the B12 is modified with polyethylene glycol (PEG) and RGD sequence as target ligand and the CB[8] is loaded with methylene blue (MB) as supramolecular photosensitizer, the SOFs can be easily prepared with wide engineering range. A uniform nanoshuttle (NanoSOF) with excellent water dispersibility and bioavailability can be prepared by simply mixing the B12‐PEG‐RGD and MB@CB[8] in aqueous solution. As a proof of concept, the NanoSOF is applied as smart nanomedicine for targeted tumor imaging and PDT of tumor, and excellent tumor targeting ability as well as tumor ablation ability can be achieved in vivo. This work highlights the modular design of SOFs with exchangeable units/functions based on chaotropic effect, which may arouse research interests in many other fields.
Zinc Microrocket Pills: Fabrication and Characterization toward Active Oral Delivery
Authors: Mundaca‐Uribe Rodolfo , Esteban‐Fernández de Ávila Berta , Holay Maya , Lekshmy Venugopalan Pooyath , Nguyen Bryan , Zhou Jiarong , Abbas Amal , Fang Ronnie H. , Zhang Liangfang , Wang Joseph 
Published: August 2020

AbstractHere the fabrication of a zinc (Zn) microrocket pill is reported, and its unique features toward active and enhanced oral delivery application are demonstrated. By loading Zn‐based tubular microrockets into an orally administrable pill formulation, the resulting Zn microrocket pill can rapidly dissolve in the stomach, releasing numerous encapsulated Zn microrockets that are instantaneously activated and then propel in the gastric fluid. The released Zn microrockets display efficient propulsion without being affected by the presence of the inactive excipient materials of the pill. An in vivo retention study performed in mice clearly shows that the active pill dissolution and powerful acid‐driven Zn microrocket propulsion greatly enhance the microrocket retention within the gastric tissue without causing toxic effects. By combining the active delivery feature of Zn microrockets with the oral administration of a pill, the Zn microrocket pill holds considerable potential for active oral delivery of various therapeutics for diverse medical applications.
Chiral Transition Metal Oxides: Synthesis, Chiral Origins, and Perspectives
Authors: Li Yiwen , Wang Xiongbin , Miao Jun , Li Jiagen , Zhu Xi , Chen Rui , Tang Zikang , Pan Ruikun , He Tingchao , Cheng Jiaji 
Published: August 2020

AbstractTransition metal oxides (TMOs) consist of a series of solid materials, exhibiting a wide variety of structures with tunability and versatile physicochemical properties. Such a statement is undeniably true for chiral TMOs since the introduction of chirality brings in not only active optical activities but also geometrical anisotropy due to the symmetry‐breaking effect. Although progressive investigations have been made for accurately controlled synthesis and relevant explanations on the chirality origin of such materials, the overall field of chiral TMOs is still in its infancy with adequate space for interdisciplinary communications and development. Herein, therefore, recent advances in both experimental phenomena and theoretical calculations in this area are reviewed, to elucidate the underlying chiral origin with respect to their fabrications process, triggering new insights for further evolution of this field.
Autonomous Surface Reconciliation of a Liquid‐Metal Conductor Micropatterned on a Deformable Hydrogel
Authors: Park Jung‐Eun , Kang Han Sol , Koo Min , Park Cheolmin 
Published: August 2020

AbstractSpreading liquid droplets on solid surfaces is a core topic in physical chemistry with significant technological implications. Liquid metals, which are eutectic alloys of constituent metal atoms with low melting temperatures, are practically useful, but difficult to spread on solid surfaces because of their high surface tension. This makes it difficult to use liquid metals as deformable on‐board microcircuitry electrodes, despite their intrinsic deformability. In this study, it is discovered that eutectic gallium–indium (EGaIn) can be spread onto the surface of chemically cross‐linked hydrogels consisting of aliphatic alkyl chains with numerous hydroxyl groups (OH), thus facilitating the development of directly micropatterned EGaIn electrodes. More importantly, EGaIn patterned on a hydrogel autonomously reconciliates its surface to form a firm hydrogel interface upon mechanical deformation of the hydrogel. This autonomous surface reconciliation of EGaIn on hydrogels allows researchers to reap the benefits of chemically modified hydrogels, such as reversible stretching, self‐healing, and water‐swelling capability, thereby facilitating the fabrication of superstretchable, self‐healable, and water‐swellable liquid‐metal electrodes with very high conductance tolerance upon deformation. Such electrodes are suitable for a variety of deformable microelectronic applications.
On‐Demand Local Modification of High‐Tc Superconductivity in Few Unit‐Cell Thick Bi2Sr2CaCu2O8+δ
Authors: Ghosh Sanat , Vaidya Jaykumar , Datta Sawani , Pandeya Ram Prakash , Jangade Digambar A. , Kulkarni Ruta N. , Maiti Kalobaran , Thamizhavel Arumugam , Deshmukh Mandar M. 
Published: August 2020

AbstractHigh‐temperature superconductors (HTSs) are important for potential applications and for understanding the origin of strong correlations. Bi2Sr2CaCu2O8+δ (BSCCO), a van der Waals material, offers a platform to probe the physics down to a unit‐cell. Guiding the flow of electrons by patterning 2DEGS and oxide heterostructures has brought new functionality and access to new science. Similarly, modifying superconductivity in HTS locally, on a small length scale, is of immense interest for superconducting electronics. A route to modify superconductivity locally by depositing metal on the surface is reported here by transport studies on few unit‐cell thick BSCCO. Deposition of chromium (Cr) on the surface over a selected area of BSCCO results in insulating behavior of the underlying region. Cr locally depletes oxygen in CuO2 planes and disrupts the superconductivity in the layers below. This technique of modifying superconductivity is suitable for making sub‐micrometer superconducting wires and more complex superconducting devices.
Multiple Mechanical Gradients are Responsible for the Strong Adhesion of Spider Attachment Hair
Authors: Flenner Silja , Schaber Clemens F. , Krasnov Igor , Stieglitz Hergen , Rosenthal Martin , Burghammer Manfred , Gorb Stanislav N. , Müller Martin 
Published: August 2020

AbstractWandering spiders climb vertically and walk upside‐down on rough and smooth surfaces using a nanostructured attachment system on their feet. The spiders are assumed to adhere by intermolecular van der Waals forces between the adhesive structures and the substrate. The adhesive elements are arranged highly ordered on the hierarchically structured attachment hair (setae). While walking, it has been suggested that the spiders apply a shear force on their legs to increase friction. However, the detailed mechanical behavior of the hair's structures during attachment and detachment remains unknown. Here, gradients of the mechanical properties of the attachment hair on different length scales that have evolved to support attachment, stabilize adhesion in contact, and withstand high stress at detachment, examined by in situ experiments, are shown. Shearing helps to self‐align the adhesive elements with the substrate. The study is anticipated to contribute to the development of optimized artificial dry adhesives.
Modification of the Electronic Transport in Atomically Thin WSe2 by Oxidation
Authors: Lin Yu‐Chuan , Bersch Brian M. , Addou Rafik , Xu Ke , Wang Qingxiao , Smyth Christopher M. , Jariwala Bhakti , Walker Roger C. , Fullerton‐Shirey Susan K. , Kim Moon J. , Wallace Robert M. , Robinson Joshua A. 
Published: August 2020

AbstractAtomically thin tungsten diselenide (WSe2) is a promising 2D semiconductor for nanoelectronics and optoelectronics. Using UV ozone and low‐power O2 plasma treatments, it is demonstrated that the formation of WSe2(1−x)O2x (WSeyOx) leads to hysteretic behavior in vertical transport measurements and also enables to an improvement in the p‐type transfer characteristics in lateral transport measurements. The amount of oxidation correlates well with the resistive switch behavior in oxidized WSe2/graphene, and WSeyOx formation under the electrical contact of the horizontal devices leads to increased p‐branch on/off by 100×. In addition to its effect for residue removal, oxidation on field effect transistor channel also helps mitigate n‐type dominated transfer characteristics of WSe2 commonly seen on sapphire. It is demonstrated that light oxidation of WSe2 is a multifunctional post‐growth treatment that enables vertical resistive switch junctions, contact improvement, and continuous tuning of transistor transport properties.
Self‐Oscillation of Locally Heated Water Vapor Microbubbles in Degassed Water
Authors: Namura Kyoko , Okai Shunsuke , Kumar Samir , Nakajima Kaoru , Suzuki Motofumi 
Published: August 2020

AbstractThe self‐oscillation of water vapor microbubbles in degassed water is experimentally investigated by using the photothermal conversion effect of an FeSi2 thin film. A laser spot on the FeSi2 thin film is used as a heat resistant and localized heat source with flexible size and power. The local heating of the degassed water leads to the generation of a water vapor microbubble, which shows self‐oscillation at 0.1–0.7 MHz under continuous heating. The bubble oscillation frequency shows the maximum value when the absorbed power density reaches 1 mW µm−2 ( = 1 × 109 W m−2), regardless of the laser spot size. This value is close to the critical heat flux for highly subcooled boiling of water. The anomalous dependence of the self‐oscillation frequency on the input power density is explained by the transition from nucleate boiling to local film boiling. Additionally, a numerical analysis suggests that the bubble oscillation exceeding 1 mW µm−2 is attributed to the dried region on the laser spot and the periodic contact of the liquid water to the small heater. These results are useful for understanding and enhancing the flow generated around the water vapor bubble, and the design of microscale cooling devices.
The Adhesion of Mica Nanolayers on a Silicon Substrate in Air
Authors: Yu Bowen , Wang Fei , Wang Shiliang , Hu Yujin , Huang Han 
Published: August 2020

AbstractMica nanolayers (MNL) are a new dielectric material that can improve the electron transport properties of Si based microelectronic devices. However, the mechanical reliability of such devices is not well understood because measurement of the adhesion between an MNL and a Si substrate is insufficiently accurate. The recent work reports a bridging method that is developed based on the linear beam theory and can characterize the adhesion of MNL on a mica substrate in a reasonably accuracy. In this work, the accuracy of the bridging method is improved by using a nonlinear mechanical model. 15 MNL specimens are measured on a Si substrate in air and the new model gives an average adhesion energy of 119.69 ± 20.47 mJ m–2. The effect of environment on the adhesion is also investigated. The increase in temperature from 25 to 300 °C enhances adhesion, attributed to the increased bonding effect of interfacial contaminants. When humidity is below a threshold value, 80% in this case, the adhesion energy remains unchanged, but above the threshold, the nanobridges collapse during testing. Molecular dynamics simulation reveal that the collapse is because the increase of interfacial water molecules reduces the frictional force between the MNL and Si substrate.
Improved Performance and Stability of Organic Solar Cells by the Incorporation of a Block Copolymer Interfacial Layer
Authors: Pérez Gabriel E. , Erothu Harikrishna , Topham Paul D. , Bastianini Francesco , Alanazi Tarek I. , Bernardo Gabriel , Parnell Andrew J. , King Stephen M. , Dunbar Alan D. F. 
Published: August 2020

AbstractIn a proof‐of‐concept study, this work demonstrates that incorporating a specifically designed block copolymer as an interfacial layer between a charge transport layer and the photoactive layer in organic solar cells can enhance the interface between these layers leading to both performance and stability improvements of the device. This is achieved by incorporating a P3HT50‐b‐PSSx block copolymer as an interfacial layer between the hole transporting and photoactive layers, which results in the improvement of the interfacial roughness, energy level alignment, and stability between these layers. Specifically, the incorporation of a 10 nm P3HT50‐b‐PSS16 and a 13 nm P3HT50‐b‐PSS23 interfacial layer results in a 9% and a 12% increase in device efficiency respectively compared to the reference devices. In addition to having a higher initial efficiency, the devices with the block copolymer continue to have a higher normalized efficiency than the control devices after 2200 h of storage, demonstrating that the block copolymer not only improves device efficiency, but crucially, prevents degradation by stabilizing the interface between the hole transporting layer and the photoactive layer. This study proves that appropriately designed and optimized block copolymers can simultaneously stabilize and improve the efficiency of organic solar cells.
Recent Progress of Flexible Lithium–Air/O2 Battery
Authors: Liu Tong , Yang Xiao‐Yang , Zhang Xin‐Bo 
Published: August 2020

AbstractAlong with the popularity of flexible electronic products, the requirements for flexible energy storage devices are also increasing, including high energy density, long‐term stability, and high‐grade safety. Among various flexible energy storage devices, flexible lithium–air batteries are expected to be one of the best candidates due to their high energy density and environmental friendliness. In order to realize the broad application of flexible lithium–air batteries with high performance, flexibility, and safety, many efforts are made. Here, the recent achievements in flexible lithium–air batteries are discussed, highlighting the flexible cathodes, polymer electrolytes, flexible anodes, operating in ambient air, and battery structural design. Besides, future research perspectives in flexible lithium–air batteries are presented.
Hydrogen‐Rich Syngas Production by DC Thermal Plasma Steam Gasification from Biomass and Plastic Mixtures
Authors: Ma WenChao , Chu Chu , Wang Ping , Guo ZhenFei , Lei ShiJun , Zhong Lei , Chen GuanYi 
Published: August 2020

AbstractRecently, thermal plasma gasification has attracted much attention due to hydrogen‐rich syngas production. In this research, wood sawdust and high density polyethylene (HDPE) mixtures have been investigated under plasma steam gasification with various HDPE contents (0–100%), at different input plasma powers (16–24 kW) and varying steam flow/carbon flow (S/C) ratios (0.2–1.8). The single‐factor analysis indicates that the real H2 yield at 80 wt% HDPE is 23.99% higher than the theoretically calculated results. This significant improvement in hydrogen yield confirms the synergetic gasification effects between HDPE and biomass. The yield and proportion of H2 show a climbing trend with the increase of input power, while showing a trend from rising to descending with the increase of S/C ratio. Under the optimal conditions (the HDPE ratio of 80%, the input power of 22 kW, the S/C ratio of 1.0), the H2 yield is as high as 78.55 mol kg−1 and the proportion of H2 in syngas reaches 66.91%. Redundancy analysis shows that the HDPE content, input power and S/C ratio can explain 39.8%, 12.4%, and 10.6% of the variations of syngas properties respectively. The input power has the largest correlation with the increase of H2 yield among these three factors.
Radio Frequency Driven Heating of Catalytic Reactors for Portable Green Chemistry
Authors: Patil Nutan , Mishra Naveen K. , Saed Mohammad A. , Green Micah J. , Wilhite Benjamin A. 
Published: August 2020

AbstractHere, a novel integration is proposed for radio frequency (1–300 MHz) responsive nanomaterials with conventional catalytic materials to realize a new class of heterogeneous catalysts that undergo uniform volumetric and localized heating to drive chemical transformations at the modular scale. Approximately 80% of chemical manufacturing involves heterogeneous catalytic reactions, which currently require heating via steam utilities or fired furnaces, and thus contribute to global greenhouse gas emissions while also limiting distributed chemicals production. This approach uses an electric route to produce chemicals where radio frequency (RF) electromagnetic fields and their interaction with carbon/ceramic nanomaterials are utilized to selectively heat the catalyst composition. A proof‐of‐concept is demonstrated using the commonly studied methanol steam reforming reaction on a platinum catalyst. In this study, two RF susceptors are used: carbon nanotubes and silicon carbide fibers. The conversion rate of methanol using RF heating is comparable to oven heating at varying temperature and catalyst combinations. This is a potential improvement over conventional catalytic reactors in that it enables small, safe, sustainable, on‐site, and on‐demand production of chemicals in the absence of traditional manufacturing infrastructure.
Nanomedicine Revisited: Next Generation Therapies for Brain Cancer
Authors: Bhargav Adip G. , Mondal Sujan K. , Garcia Cesar A. , Green Jordan J. , Quiñones‐Hinojosa Alfredo 
Published: August 2020

AbstractBrain cancer persists as a difficult‐to‐treat condition. In particular, metastatic brain cancer and malignant primary brain tumors such as glioblastoma (GBM) are among the most deadly and still carry a dismal prognosis despite current standard of care with surgery and chemo‐radiation. Recent advances in nanotechnology have led to innovative nanomedicine strategies for the treatment of brain cancers and specifically for GBM. These strategies represent promising alternative or adjunctive therapies for conventional treatment modalities and are increasingly designed to target specific cell types such as brain tumor‐initiating cells and immune cells. This review provides an update on emerging insights into these nanomedicine strategies with a focus on nanoparticles as tools that facilitate 1) drug delivery 2) gene therapy, and 3) engineered‐cellular therapy for GBM and future directions for brain cancer treatment.
Tinted Semi‐Transparent Solar Panels Allow Concurrent Production of Crops and Electricity on the Same Cropland
Authors: Thompson Elinor P. , Bombelli Emilio L. , Shubham Simon , Watson Hamish , Everard Aldous , D’Ardes Vincenzo , Schievano Andrea , Bocchi Stefano , Zand Nazanin , Howe Christopher J. , Bombelli Paolo 
Published: August 2020

AbstractAgrivoltaics describes concurrent agricultural production of crops and photovoltaic generation of electricity on the same cropland. By using tinted semi‐transparent solar panels, this study introduces a novel element to transform the concept of agrivoltaics from just solar‐sharing to selective utilization of different light wavelengths. Agrivoltaic growth of basil and spinach is tested. When compared with classical agriculture, and based on the feed‐in‐tariff of the experimental location, agrivoltaic co‐generation of biomass and electricity is calculated to result in an estimated financial gross gain up to +2.5% for basil and +35% for spinach. Marketable biomass yields do not change significantly for basil, while a statistically significant loss is observed for spinach. This is accompanied by a relative increase in the protein content for both plants grown under agrivoltaic conditions. Agrivoltaics implemented with tinted solar panels improve the biomass production per unit amount of solar radiation up to 68%, with up to 63% increase in the ratio of leaf and stem biomass to root. Agrivoltaics can enrich the portfolio of farmers, mitigate risks associated with climate, and vastly enhance global photovoltaics capacity without compromising agricultural production.
Catalytic and Dual‐Conductive Matrix Regulating the Kinetic Behaviors of Polysulfides in Flexible Li–S Batteries
Authors: Li Huanhuan , Chen Huiqin , Xue Yan , Zhang Yuting , Zhang Mengjie , Yu Wenqi , Bai Guangyue , Zhuo Kelei , Zheng Yanping 
Published: August 2020

AbstractThe main challenge in developing foldable Li–S batteries (LSB) lies in developing an electrode that is ultraflexible, conductive, and catalytic for dissolved lithium polysulfides (LiPSs). In this paper, lightweight macromolecule graphitic carbon nitride (g‐C3N4) film and a conductive polymer (CP) of poly(3,4‐ethylenedioxythiophene) shell are introduced into flexible LSBs by compositing with carbon cloth (CC). In the designed hybrid of CP/g‐C3N4@CC, 2D g‐C3N4 is used in the form of an effective trapper and functions as a continuous catalytic layer for LiPSs via the formation of pyridinic‐N‐Li bonds. This is revealed by both experimental investigations and theoretical analysis. The sandwich‐like CC and CP simultaneously bring an omnidirectional conductive network for fast interfacial reaction kinetics. With these benefits, the self‐supported CP/g‐C3N4@CC forms a powerful interaction system to fully in situ “lock” LiPSs in the commercial CC matrix. Thus, a substantially enhanced electrochemical performance is obtained at a high sulfur loading (4.7 mg cm–2) even operating in a pouch cell. This work may provide a potential avenue for practical use of high‐performance LSBs toward flexible energy‐storage devices.