Immune checkpoint blockade(ICB)therapy for cancer has achieved great success both in clinical results and on the market.At the same time,success drives more attention from scientists to improve it.However,only a small...Immune checkpoint blockade(ICB)therapy for cancer has achieved great success both in clinical results and on the market.At the same time,success drives more attention from scientists to improve it.However,only a small portion of patients are responsive to this therapy,and it comes with a unique spectrum of side effects termed immunerelated adverse events(irAEs).The use of nanotechnology could improve ICBs’delivery to the tumor,assist them in penetrating deeper into tumor tissues and alleviate their irAEs.Liposomal nanomedicine has been investigated and used for decades,and is well-recognized as the most successful nano-drug delivery system.The successful combination of ICB with liposomal nanomedicine could help improve the efficacy of ICB therapy.In this review,we highlighted recent studies using liposomal nanomedicine(including new emerging exosomes and their inspired nanovesicles)in associating ICB therapy.展开更多
Fundamental research and practical applications have examined the manipulation of gas bubbles on open surfaces in lowsurface-tension,high-pressure,and high-acidity,-alkalinity,or-salinity environments.However,to the b...Fundamental research and practical applications have examined the manipulation of gas bubbles on open surfaces in lowsurface-tension,high-pressure,and high-acidity,-alkalinity,or-salinity environments.However,to the best of our knowledge,effi cient and general approaches to achieve the smart manipulation of gas bubbles in these harsh environments are limited.Herein,a Fluorinert-infused shape-gradient slippery surface(FSSS)that could eff ectively regulate the behavior of gas bubbles in harsh environments was successfully fabricated.The unique capability of FSSS was mainly attributed to the properties of Fluorinert,which include chemical inertness and incompressibility.The shape-gradient morphology of FSSS could induce asymmetric driving forces to move gas bubbles directionally on open surfaces.Factors infl uencing gas bubble transport on FSSS,such as the apex angle of the slippery surface and the surface tension of the aqueous environment,were carefully investigated,and large apex angles were found to result in large initial transport velocities and short transport distances.Lowering the surface tension of the aqueous environment is unfavorable to bubble transport.Nevertheless,FSSS could transport gas bubbles in aqueous environments with surface tensions as low as 28.5±0.1 mN/m,which is lower than that of many organic solvents(e.g.,formamide,ethylene glycol,and dimethylformamide).In addition,FSSS could also realize the facile manipulation of gas bubbles in various aqueous environments,e.g.,high pressure(~6.8 atm),high acidity(1 mol/L H 2 SO 4),high alkalinity(1 mol/L NaOH),and high salinity(1 mol/L NaCl).The current fi ndings provide a source of knowledge and inspiration for studies on bubble-related interfacial phenomena and contribute to scientifi c and technological developments for controllable bubble manipulation in harsh environments.展开更多
Li metal with high-energy density is considered as the most promising anode for the next-generation rechargeable Li metal batteries;however,the growth of Li dendrites seriously hinders its practical application.Herein...Li metal with high-energy density is considered as the most promising anode for the next-generation rechargeable Li metal batteries;however,the growth of Li dendrites seriously hinders its practical application.Herein,3D free-standing carbon nanofibers modified by lithiophilic metal particles(CNF/Me,Me=Sn,Fe,Co)are obtained in situ by the electrospinning method.Benefiting from the lithophilicity,the CNF/Me composite may effectively prevent the formation of Li dendrites in the Li metal batteries.The optimized CNF/Sn–Li composite electrode exhibits a stable cycle life of over 2350 h during Li plating/stripping.When matched with typical commercial LiFePO_(4)(LFP)cathode,the LFP//CNF/Sn–Li full cell presents a high initial discharge specific capacity of 139 mAh g^(−1)at 1 C,which remains at 146 mAh g^(−1)after 400 cycles.When another state-of-the-art commercial LiNi_(0.8)Co_(0.1)Mn_(0.1)O_(2)(NCM(811))cathode is used,the assembled NCM//CNF/Sn–Li full cell shows a large initial specific discharge capacity of 206 mAh g^(−1)at substantially enhanced 10 C,which keeps at the good capacity of 99 mAh g^(−1)after 300 cycles.These results are greatly superior to the counterparts with Li as the anodes,indicating the great potential for practical utilization of the advanced CNF/Sn–Li electrode.展开更多
Paraffin deposition is a severe global problem during crude oil production and transportation.To inhibit the formation of paraffin deposits,the commonly used methods are mechanical cleaning,coating the pipe to provide...Paraffin deposition is a severe global problem during crude oil production and transportation.To inhibit the formation of paraffin deposits,the commonly used methods are mechanical cleaning,coating the pipe to provide a smooth surface and reduce paraffin adhesion,electric heating,ultrasonic and microbial treatments,the use of paraffin inhibitors,etc.Pipeline coatings not only have the advantages of simple preparation and broad applications,but also maintain a long-term efficient and stable effect.In recent years,important progress has been made in research on pipe coatings for mitigating and preventing paraffin deposition.Several novel superhydrophilic organogel coatings with low surface energy were successfully prepared by bionic design.This paper reviews different types of coatings for inhibiting wax deposition in the petroleum industry.The research prospects and directions of this rapidly developing field are also briefly discussed.展开更多
Mother Nature has demonstrated the importance of structural designs at multiscale:biological structural materials frequently adopt complex hierarchical structures to optimize their mechanical performance that is far b...Mother Nature has demonstrated the importance of structural designs at multiscale:biological structural materials frequently adopt complex hierarchical structures to optimize their mechanical performance that is far beyond their abiotic counterparts[1].One of the most studied biological materials is the nacreous part in some mollusk shells,展开更多
The oxygen evolution reaction(OER)is an electrochemical bottleneck half-reaction in some important energy conversion systems(e.g.,water splitting),which is traditionally mediated by iridium oxides in acidic environmen...The oxygen evolution reaction(OER)is an electrochemical bottleneck half-reaction in some important energy conversion systems(e.g.,water splitting),which is traditionally mediated by iridium oxides in acidic environment.Perovskite-structured Ir-containing oxides(e.g.,SrIrO_(3))are a family of striking electrocatalysts due to their high specific activity,but this excellent quality is difficultly transferred to a nano-electrocatalyst with large active surface and good structural stability.Here,we present a synthesis method that produces a 2D ultrathin{001}-faceted SrIrO_(3)perovskite(2D-SIO)with a thickness of∼5 nm and high surface area(57.6 m^(2)g^(−1)).We show that 2D-SIO can serve as a highly active and stable electrocatalytic nanomaterial for OER under acidic conditions.This perovskite nanomaterial produces 10 mA cm^(−2)current density at a low overpotential(η,243 mV),and maintains its catalytic activity after 5000 continuous cyclic measurements.Besides ultrathin structure and large surface area,the exposed{001}facets are found to be the most crucial and unique structural factor for achieving high catalytic activity and structural stability.Our joint experimental and theoretical results demonstrate that these advantageous microstructural features of 2D-SIO endow it with a strong capability to generate the key O^(*)intermediates,and thereby facilitate O–O bond formation and the OER.展开更多
Hydrogels have drawn considerable attention in the past two decades due to their excellent biocompatibility and multi-stimuli responsiveness. They have a wide range of applications in the fields related to tissue engi...Hydrogels have drawn considerable attention in the past two decades due to their excellent biocompatibility and multi-stimuli responsiveness. They have a wide range of applications in the fields related to tissue engineering, sensors and biomedicine. Their applications are strongly influenced by the surface properties of hydrogels and the interfacial interactions between hydrogels and other substrates. In particular, the surface wettability and adhesion of hydrogels decide their applications as drug carriers and wound dressing materials. Nevertheless, there is a lack of systematic discussion on the surface functionalization strategies of hydrogels. Therefore, this review aims at summarizing the strategies of functionalizing the surfaces of hydrogels and bonding hydrogels with other solid substrates. It also explores the challenges and future perspectives of interfacial engineering of hydrogels.展开更多
The improved performance of a wavelength-tunable arrayed waveguide grating (AWG) is demonstrated, including the crosstalk, insertion loss and the wavelength tuning efficiency. A reduced impact of the fabrication proce...The improved performance of a wavelength-tunable arrayed waveguide grating (AWG) is demonstrated, including the crosstalk, insertion loss and the wavelength tuning efficiency. A reduced impact of the fabrication process on the AWG is achieved by the design of bi-level tapers. The wavelength tuning of the AWG is achieved according to the thermo-optic effect of silicon, and uniform heating of the silicon waveguide layer is achieved by optimizing the heater design. The fabricated AWG shows a minimum crosstalk of 16 dB, a maximum insertion loss of 3.91 dB and a wavelength tuning efficiency of 8.92 nm/W, exhibiting a ~8 dB improvement of crosstalk, ~2.1 dB improvement of insertion loss and ~5 nm/W improvement of wavelength tuning efficiency, compared to our previous reported results.展开更多
As a novel class of metallic materials, bulk metallic glasses(BMGs) have attracted a great deal of attention owing to their technological promise for practical engineering applications. In nature, biological materials...As a novel class of metallic materials, bulk metallic glasses(BMGs) have attracted a great deal of attention owing to their technological promise for practical engineering applications. In nature, biological materials exhibit inherent multifunctional integration, which provides some inspiration for scientists and engineers to construct multifunctional artificial materials. In this contribution, inspired by superhydrophobic self-cleaning lotus leaves, multifunctional bulk metallic glasses(BMG) materials have been fabricated through the thermoplastic forming-based process followed by the SiO_2/soot deposition. To mimic the microscale papillae of the lotus leaf, the BMG micropillar with a hemispherical top was first fabricated using micro-patterned silicon templates based on thermoplastic forming. The deposited randomly distributed SiO_2/soot nanostructures covered on BMG micropillars are similar to the branch-like nanostructures on papillae of the lotus leaf. Micro-nanoscale hierarchical structures endow BMG replica with superhydrophobicity, a low adhesion towards water, and self-cleaning, similar to the natural lotus leaf. Furthermore, on the basis of the observation of the morphology of BMG replica in the Si mould, the formation mechanism of BMG replica was proposed in this work. The BMG materials with multifunction integration would extend their practical engineering applications and we expect this method could be widely adopted for the fabrication of other multifunctional BMG surfaces.展开更多
Highly anisotropic thermal conductive materials are of significance in thermal management applications. However,accurate determination of ultrathin composite thermal properties is a daunting task due to the tiny therm...Highly anisotropic thermal conductive materials are of significance in thermal management applications. However,accurate determination of ultrathin composite thermal properties is a daunting task due to the tiny thermal conductance,severely hindering the further exploration of novel efficient thermal management materials, especially for size-confined environments. In this work, by utilizing a hybrid measuring method, we demonstrate an accurate determination of thermal properties for montmorillonite/reduced graphene oxide(MMT/r GO) composite film with a thickness range from 0.2 μm to2 μm. The in-plane thermal conductivity measurement is realized by one-dimensional(1D) steady-state heat conduction approach while the cross-plane one is achieved via a modified 3ω method. As-measured thermal conductivity results are cross-checked with different methods and known materials, revealing the high measurement accuracy. A high anisotropic ratio of 60.5, independent of composite thickness, is observed in our measurements, further ensuring the negligible measurement error. Notably, our work develops an effective approach to the determination of ultrathin composite thermal conductivity, which may promote the development of ultrathin composites for potential thermal-related applications.展开更多
A new variational method is proposed to investigate the dynamics of the thin film in a coating flow where a liquid is delivered through a fixed slot gap onto a moving substrate. A simplified ODE system has also been d...A new variational method is proposed to investigate the dynamics of the thin film in a coating flow where a liquid is delivered through a fixed slot gap onto a moving substrate. A simplified ODE system has also been derived for the evolution of the thin film whose thickness hf is asymptotically constant behind the coating front. We calculate the phase diagram as well as the film profiles and approximate the film thickness theoretically, and agreement with the well-known scaling law as Ca2/3 is found.展开更多
Capillary filling in small length scale is an important process in nanotechnology and microfabrication. When one end of the tube or channel is sealed, it is important to consider the escape of the trapped gas. We deve...Capillary filling in small length scale is an important process in nanotechnology and microfabrication. When one end of the tube or channel is sealed, it is important to consider the escape of the trapped gas. We develop a dynamic model on capillary filling in closed-end tubes, based on the diffusion-convection equation and Henry's law of gas dissolution. We systematically investigate the filling dynamics for various sets of parameters, and compare the results with a previous model which assumes a linear density profile of dissolved gas and neglect the convective term.展开更多
Thermally conductive polymer nanocomposites integrated with lightweight,excellent flexural strength,and high fracture toughness(KIc)would be of great use in many fields.However,achieving all of these properties simult...Thermally conductive polymer nanocomposites integrated with lightweight,excellent flexural strength,and high fracture toughness(KIc)would be of great use in many fields.However,achieving all of these properties simultaneously remains a great challenge.Inspired by natural nacre,here we demonstrate a lightweight,strong,tough,and thermally conductive boron nitride nanosheet/epoxy layered(BNNEL)nanocomposite.Because of the layered structure and enhancing the interfacial interactions through hydrogen bonding and Si–O–B covalent bonding,the resulting nacre-inspired BNNEL nanocomposites show high fracture toughness of~4.22 MPa·m^(1/2),which is 7 folds as high as pure epoxy.Moreover,the BNNEL nanocomposites demonstrate sufficient flexural strength(~168.90 MPa,comparable to epoxy resin),while also being lightweight(~1.23 g/cm^(3)).Additionally,the BNNEL nanocomposites display a thermal conductivity(κ)of~0.47 W/(m·K)at low boron nitride nanosheet loading of 2.08 vol.%,which is 2.7 times higher than that of pure epoxy resin.The developed nacre-inspired strategy of layered structure design and interfacial enhancement provides an avenue for fabricating high mechanical properties and thermally conductive polymer nanocomposites.展开更多
The high power density and intelligence of next-generation flexible electronic devices bring many challenges to fabricate flexible composite films with electromagnetic interference(EMI)shielding effectiveness(SE)prope...The high power density and intelligence of next-generation flexible electronic devices bring many challenges to fabricate flexible composite films with electromagnetic interference(EMI)shielding effectiveness(SE)property and excellent toughness via a simple method.Herein,inspired by the layered structure and biopolymer matrix networks in natural nacre,nacre-like layered Ti_(3)C2TX(MXene)/aramid nanofiber(ANF)films were fabricated through sol-gel,vacuum-assisted filtration,and hot-pressing.Three-dimensional(3D)interconnected aramid nanofibers networks between adjacent layered MXene result in an ultralong strain-to-failure of the film.Even though the functional filler MXene contents are as high as 60 wt.%and 70 wt.%,the strain-to-failure of the films could reach astonishing values of 18.34%±1.86%and 14.43%±1.26%,respectively.And the tensile strength could maintain about 85 MPa.Excitingly,with such a high filler,the film can also withstand double folding and vigorous rubbing without damage,which could better adapt to a harsh application environment.The result means that this work provides a convenient way to prepare other high functional filler composite films with excellent mechanical performance.The EMI SE values could reach 45 and 52.15 dB at 60 wt.%and 70 wt.%MXene in 8.2–12.4 GHz.Meanwhile,the films have prominent Joule heating properties,high sensitivity(<15 s),small voltage operation(0.5 V),and high operation constancy(1300 s).Therefore,nacre-inspired MXene/ANF composite films in this work have ability to apply in many areas including communication technology,military,and aerospace.展开更多
Nacre has inspired research to fabricate tough bulk composites for practical applications using inorganic nanomaterials as building blocks.However,with the considerable pressure to reduce global carbon emissions,prepa...Nacre has inspired research to fabricate tough bulk composites for practical applications using inorganic nanomaterials as building blocks.However,with the considerable pressure to reduce global carbon emissions,preparing nacre-inspired composites remains a significant challenge using more economical and environmentally friendly building blocks.Here we demonstrate tough and conductive nacre by assembling aragonite platelets exfoliated from natural nacre,with liquid metal and sodium alginate used as the “mortar”.The formation of Ga-O-C coordination bonding between the gallium ions and sodium alginate molecules reduces the voids and improves compactness.The resultant conductive nacre exhibits much higher mechanical properties than natural nacre.It also shows excellent impact resistance attributed to the synergistic strengthening and toughening fracture mechanisms induced by liquid metal and sodium alginate.Furthermore,our conductive nacre exhibits exceptional self-monitoring sensitivity for maintaining structural integrity.The proposed strategy provides a novel avenue for turning natural nacre into a valuable green composite.展开更多
To commercialize fuel cells and metal-air batteries, cost-effective, highly active catalysts for the oxygen reduction reaction (ORR) must be developed. Herein, we describe the development of low-cost, heteroatom (N...To commercialize fuel cells and metal-air batteries, cost-effective, highly active catalysts for the oxygen reduction reaction (ORR) must be developed. Herein, we describe the development of low-cost, heteroatom (N, P, Fe) ternary-doped, porous carbons (HDPC). These materials are prepared by one-step pyrolysis of natural tea leaves treated with an iron salt, without any chemical and physical activation. The natural structure of the tea leaves provide a 3D hierarchical porous structure after carbonization. Moreover, heteroatom containing organic compounds in tea leaves act as precursors to functionalize the resultant carbon frameworks. In addition, we found that the polyphenols present in tea leaves act as ligands, reacting with Fe ions to form coordination compounds; these complexes acted as the precursors for Fe and N active sites. After pyrolysis, the as-prepared HDPC electrocatalysts, especially HDPC-800 (pyrolyzed at 800℃), had more positive onsets, half-wave potentials, and higher catalytic activities for the ORR, which proceeds via a direct four-electron reaction pathway in alkaline media, similar to commercial Pt/C catalysts. Furthermore, HDPC-X also showed enhanced durability and better tolerance to methanol crossover and CO poisoning effects in comparison to commercial Pt/C, making them promising alternatives for state-of-the-art ORR electrocatalysts for electrochemical energy conversion. The method used here provides valuable guidelines for the design of high-performance ORR electrocatalysts from natural sources at the industrial scale.展开更多
Zn-based batteries have attracted extensive attention due to their high theoretical energy density,safety,abundant resources,environmental friendliness,and low cost.They are a new energy storage and conversion technol...Zn-based batteries have attracted extensive attention due to their high theoretical energy density,safety,abundant resources,environmental friendliness,and low cost.They are a new energy storage and conversion technology with significant development potential and have been widely used in renewable energy and portable electronic devices.Considerable attempts have been devoted to improving the performance of Zn-based batteries.Specifically,battery cycle life and energy efficiency can be improved by electrolyte modification and the construction of highly efficient rechargeable Zn anodes.This review compiles the progress of the research related to Zn anodes and electrolytes,especially in the last five years.This review will introduce fundamental concepts,summarize recent development,and inspire further systematic research for high-performance Zn-based batteries in the future.展开更多
In recent years,numerous studies have been reported for oil/water separation,such as superoleophilic materials for oil absorption and underwater superoleophobic membranes for continuous separation.However,for the reco...In recent years,numerous studies have been reported for oil/water separation,such as superoleophilic materials for oil absorption and underwater superoleophobic membranes for continuous separation.However,for the recovery of oil slick pollution on near-shore ocean surface caused by various reasons,large area and fast availability of used materials are needed to be considered.Herein,we report an efficient and environmentally friendly method to fast process nylon mesh by surface diffuse atmospheric plasma(SDAP)for large-area oil/water separation.Nylon mesh is funcionalized by atmospheric plasma to generate micro/nano composite structures on the surface,resulting in superhydrophilicity and underwater superoleophobicity within only seconds.The pre-wetted modified nylon mesh can achieve high efficiency(>99.9%)and circulating water flux(~30,000 L·m^(-2)·h^(-1)),with high intrusion pressure(~3 kPa)and universality in oil/water separation.Regular plasma unconditionally generated in the atmosphere with the merit of efficiently functionalizing surface has the potential of large-area materials treatment.This study might take one step further for large-area industrial oily wastewater recovery and even oil slicks collection in near-shore water bodies.展开更多
基金supported by the National Science Fund for Distinguished Young Scholars(Overseas).
文摘Immune checkpoint blockade(ICB)therapy for cancer has achieved great success both in clinical results and on the market.At the same time,success drives more attention from scientists to improve it.However,only a small portion of patients are responsive to this therapy,and it comes with a unique spectrum of side effects termed immunerelated adverse events(irAEs).The use of nanotechnology could improve ICBs’delivery to the tumor,assist them in penetrating deeper into tumor tissues and alleviate their irAEs.Liposomal nanomedicine has been investigated and used for decades,and is well-recognized as the most successful nano-drug delivery system.The successful combination of ICB with liposomal nanomedicine could help improve the efficacy of ICB therapy.In this review,we highlighted recent studies using liposomal nanomedicine(including new emerging exosomes and their inspired nanovesicles)in associating ICB therapy.
基金supported by the Beihang University’s Young Talents(No.KG16045301)the National Natural Science Foundation(No.21805204)+1 种基金Tianjin Natural Science Foundation(No.19JCQNJC05100)Young Elite Scientists Sponsorship Program by Tianjin(No.TJSQNTJ-2018-17).
文摘Fundamental research and practical applications have examined the manipulation of gas bubbles on open surfaces in lowsurface-tension,high-pressure,and high-acidity,-alkalinity,or-salinity environments.However,to the best of our knowledge,effi cient and general approaches to achieve the smart manipulation of gas bubbles in these harsh environments are limited.Herein,a Fluorinert-infused shape-gradient slippery surface(FSSS)that could eff ectively regulate the behavior of gas bubbles in harsh environments was successfully fabricated.The unique capability of FSSS was mainly attributed to the properties of Fluorinert,which include chemical inertness and incompressibility.The shape-gradient morphology of FSSS could induce asymmetric driving forces to move gas bubbles directionally on open surfaces.Factors infl uencing gas bubble transport on FSSS,such as the apex angle of the slippery surface and the surface tension of the aqueous environment,were carefully investigated,and large apex angles were found to result in large initial transport velocities and short transport distances.Lowering the surface tension of the aqueous environment is unfavorable to bubble transport.Nevertheless,FSSS could transport gas bubbles in aqueous environments with surface tensions as low as 28.5±0.1 mN/m,which is lower than that of many organic solvents(e.g.,formamide,ethylene glycol,and dimethylformamide).In addition,FSSS could also realize the facile manipulation of gas bubbles in various aqueous environments,e.g.,high pressure(~6.8 atm),high acidity(1 mol/L H 2 SO 4),high alkalinity(1 mol/L NaOH),and high salinity(1 mol/L NaCl).The current fi ndings provide a source of knowledge and inspiration for studies on bubble-related interfacial phenomena and contribute to scientifi c and technological developments for controllable bubble manipulation in harsh environments.
基金Acknowledgements The work is supported by the National Natural Science Foundation of China (Nos. 51273008 and 51473008), the National Basic Research Program of China (No. 2012CB933200), and the National High-tech R&D Program of China (No. 2012AA030305). L. M. D. is grateful to the support from NSF (Nos. AIR-IIP-1343270 and CMMI-1400274).
基金supported by the Chinese National Natural Science Foundation(No.22075008,21571010,U0734002)National Basic Research Programs of China(973 Program,No.2014CB931800,2011CB935700)+1 种基金Chinese Aeronautic Project(No.2013ZF51069)111 Project(No.B14009).
文摘Li metal with high-energy density is considered as the most promising anode for the next-generation rechargeable Li metal batteries;however,the growth of Li dendrites seriously hinders its practical application.Herein,3D free-standing carbon nanofibers modified by lithiophilic metal particles(CNF/Me,Me=Sn,Fe,Co)are obtained in situ by the electrospinning method.Benefiting from the lithophilicity,the CNF/Me composite may effectively prevent the formation of Li dendrites in the Li metal batteries.The optimized CNF/Sn–Li composite electrode exhibits a stable cycle life of over 2350 h during Li plating/stripping.When matched with typical commercial LiFePO_(4)(LFP)cathode,the LFP//CNF/Sn–Li full cell presents a high initial discharge specific capacity of 139 mAh g^(−1)at 1 C,which remains at 146 mAh g^(−1)after 400 cycles.When another state-of-the-art commercial LiNi_(0.8)Co_(0.1)Mn_(0.1)O_(2)(NCM(811))cathode is used,the assembled NCM//CNF/Sn–Li full cell shows a large initial specific discharge capacity of 206 mAh g^(−1)at substantially enhanced 10 C,which keeps at the good capacity of 99 mAh g^(−1)after 300 cycles.These results are greatly superior to the counterparts with Li as the anodes,indicating the great potential for practical utilization of the advanced CNF/Sn–Li electrode.
文摘Paraffin deposition is a severe global problem during crude oil production and transportation.To inhibit the formation of paraffin deposits,the commonly used methods are mechanical cleaning,coating the pipe to provide a smooth surface and reduce paraffin adhesion,electric heating,ultrasonic and microbial treatments,the use of paraffin inhibitors,etc.Pipeline coatings not only have the advantages of simple preparation and broad applications,but also maintain a long-term efficient and stable effect.In recent years,important progress has been made in research on pipe coatings for mitigating and preventing paraffin deposition.Several novel superhydrophilic organogel coatings with low surface energy were successfully prepared by bionic design.This paper reviews different types of coatings for inhibiting wax deposition in the petroleum industry.The research prospects and directions of this rapidly developing field are also briefly discussed.
文摘Mother Nature has demonstrated the importance of structural designs at multiscale:biological structural materials frequently adopt complex hierarchical structures to optimize their mechanical performance that is far beyond their abiotic counterparts[1].One of the most studied biological materials is the nacreous part in some mollusk shells,
基金the financial support from the National Key R&D Program of China(2017YFA0207800)the National Natural Science Foundation of China(NSFC)(21922507)+4 种基金the Fundamental Research Funds for the Central Universitiesthe financial support from NSFC(21901083)NSFC(21621001)the China Postdoctoral Science Foundation(2021M691202)the 111 Project(B17020)for additional financial support。
文摘The oxygen evolution reaction(OER)is an electrochemical bottleneck half-reaction in some important energy conversion systems(e.g.,water splitting),which is traditionally mediated by iridium oxides in acidic environment.Perovskite-structured Ir-containing oxides(e.g.,SrIrO_(3))are a family of striking electrocatalysts due to their high specific activity,but this excellent quality is difficultly transferred to a nano-electrocatalyst with large active surface and good structural stability.Here,we present a synthesis method that produces a 2D ultrathin{001}-faceted SrIrO_(3)perovskite(2D-SIO)with a thickness of∼5 nm and high surface area(57.6 m^(2)g^(−1)).We show that 2D-SIO can serve as a highly active and stable electrocatalytic nanomaterial for OER under acidic conditions.This perovskite nanomaterial produces 10 mA cm^(−2)current density at a low overpotential(η,243 mV),and maintains its catalytic activity after 5000 continuous cyclic measurements.Besides ultrathin structure and large surface area,the exposed{001}facets are found to be the most crucial and unique structural factor for achieving high catalytic activity and structural stability.Our joint experimental and theoretical results demonstrate that these advantageous microstructural features of 2D-SIO endow it with a strong capability to generate the key O^(*)intermediates,and thereby facilitate O–O bond formation and the OER.
基金financially supported by the National Natural Science Foundation of China(No.21574004)Xiamen Southern Oceanographic Center(No.14GQT61HJ31)+3 种基金the 111 project(No.B14009)the Fundamental Research Funds for the Central Universitiesthe National ‘Young Thousand Talents Program’the Academic Excellence Foundation of BUAA for PHD Students
文摘Hydrogels have drawn considerable attention in the past two decades due to their excellent biocompatibility and multi-stimuli responsiveness. They have a wide range of applications in the fields related to tissue engineering, sensors and biomedicine. Their applications are strongly influenced by the surface properties of hydrogels and the interfacial interactions between hydrogels and other substrates. In particular, the surface wettability and adhesion of hydrogels decide their applications as drug carriers and wound dressing materials. Nevertheless, there is a lack of systematic discussion on the surface functionalization strategies of hydrogels. Therefore, this review aims at summarizing the strategies of functionalizing the surfaces of hydrogels and bonding hydrogels with other solid substrates. It also explores the challenges and future perspectives of interfacial engineering of hydrogels.
基金Supported by the National Key R&D Program of China under Grant No 2016YFB0402504
文摘The improved performance of a wavelength-tunable arrayed waveguide grating (AWG) is demonstrated, including the crosstalk, insertion loss and the wavelength tuning efficiency. A reduced impact of the fabrication process on the AWG is achieved by the design of bi-level tapers. The wavelength tuning of the AWG is achieved according to the thermo-optic effect of silicon, and uniform heating of the silicon waveguide layer is achieved by optimizing the heater design. The fabricated AWG shows a minimum crosstalk of 16 dB, a maximum insertion loss of 3.91 dB and a wavelength tuning efficiency of 8.92 nm/W, exhibiting a ~8 dB improvement of crosstalk, ~2.1 dB improvement of insertion loss and ~5 nm/W improvement of wavelength tuning efficiency, compared to our previous reported results.
基金the National Natural Science Foundation of China (21273016, 51271195)the National Basic Research Program of China (2013CB933003, 2015CB856800)+1 种基金the Program for New Century Excellent Talents in University, Beijing Higher Education Young Elite Teacher Project, the Fundamental Research Funds for the Central Universities, 111 project (B14009)the Key Research Program of the Chinese Academy of Sciences (KJZDEW-M01, M03)
文摘As a novel class of metallic materials, bulk metallic glasses(BMGs) have attracted a great deal of attention owing to their technological promise for practical engineering applications. In nature, biological materials exhibit inherent multifunctional integration, which provides some inspiration for scientists and engineers to construct multifunctional artificial materials. In this contribution, inspired by superhydrophobic self-cleaning lotus leaves, multifunctional bulk metallic glasses(BMG) materials have been fabricated through the thermoplastic forming-based process followed by the SiO_2/soot deposition. To mimic the microscale papillae of the lotus leaf, the BMG micropillar with a hemispherical top was first fabricated using micro-patterned silicon templates based on thermoplastic forming. The deposited randomly distributed SiO_2/soot nanostructures covered on BMG micropillars are similar to the branch-like nanostructures on papillae of the lotus leaf. Micro-nanoscale hierarchical structures endow BMG replica with superhydrophobicity, a low adhesion towards water, and self-cleaning, similar to the natural lotus leaf. Furthermore, on the basis of the observation of the morphology of BMG replica in the Si mould, the formation mechanism of BMG replica was proposed in this work. The BMG materials with multifunction integration would extend their practical engineering applications and we expect this method could be widely adopted for the fabrication of other multifunctional BMG surfaces.
基金Project supported by the National Basic Research Program of China (Grant No. 2016YFA0200800)the Strategic Priority Research Program of Chinese Academy of Sciences (Grant Nos. XDB30000000 and XDB07030100)+2 种基金the Sinopec Innovation Scheme (A-527)the National Key Research and Development Program of China (Grant No. 2021YFA0715700)the National Science Fund for Distinguished Young Scholars, China (Grant No. 52125302)。
文摘Highly anisotropic thermal conductive materials are of significance in thermal management applications. However,accurate determination of ultrathin composite thermal properties is a daunting task due to the tiny thermal conductance,severely hindering the further exploration of novel efficient thermal management materials, especially for size-confined environments. In this work, by utilizing a hybrid measuring method, we demonstrate an accurate determination of thermal properties for montmorillonite/reduced graphene oxide(MMT/r GO) composite film with a thickness range from 0.2 μm to2 μm. The in-plane thermal conductivity measurement is realized by one-dimensional(1D) steady-state heat conduction approach while the cross-plane one is achieved via a modified 3ω method. As-measured thermal conductivity results are cross-checked with different methods and known materials, revealing the high measurement accuracy. A high anisotropic ratio of 60.5, independent of composite thickness, is observed in our measurements, further ensuring the negligible measurement error. Notably, our work develops an effective approach to the determination of ultrathin composite thermal conductivity, which may promote the development of ultrathin composites for potential thermal-related applications.
基金Project supported by the National Natural Science Foundation of China(Grant Nos.91630208,91641107,and 11771437)
文摘A new variational method is proposed to investigate the dynamics of the thin film in a coating flow where a liquid is delivered through a fixed slot gap onto a moving substrate. A simplified ODE system has also been derived for the evolution of the thin film whose thickness hf is asymptotically constant behind the coating front. We calculate the phase diagram as well as the film profiles and approximate the film thickness theoretically, and agreement with the well-known scaling law as Ca2/3 is found.
基金Project supported by the National Natural Science Foundation of China(Grant Nos.21434001,21504004,and 21774004)
文摘Capillary filling in small length scale is an important process in nanotechnology and microfabrication. When one end of the tube or channel is sealed, it is important to consider the escape of the trapped gas. We develop a dynamic model on capillary filling in closed-end tubes, based on the diffusion-convection equation and Henry's law of gas dissolution. We systematically investigate the filling dynamics for various sets of parameters, and compare the results with a previous model which assumes a linear density profile of dissolved gas and neglect the convective term.
基金supported by the National Key Research and Development Program of China(No.2021YFA0715700)the National Science Fund for Distinguished Young Scholars(No.52125302),National Natural Science Foundation of China(No.22075009)111 Project(No.B14009).
文摘Thermally conductive polymer nanocomposites integrated with lightweight,excellent flexural strength,and high fracture toughness(KIc)would be of great use in many fields.However,achieving all of these properties simultaneously remains a great challenge.Inspired by natural nacre,here we demonstrate a lightweight,strong,tough,and thermally conductive boron nitride nanosheet/epoxy layered(BNNEL)nanocomposite.Because of the layered structure and enhancing the interfacial interactions through hydrogen bonding and Si–O–B covalent bonding,the resulting nacre-inspired BNNEL nanocomposites show high fracture toughness of~4.22 MPa·m^(1/2),which is 7 folds as high as pure epoxy.Moreover,the BNNEL nanocomposites demonstrate sufficient flexural strength(~168.90 MPa,comparable to epoxy resin),while also being lightweight(~1.23 g/cm^(3)).Additionally,the BNNEL nanocomposites display a thermal conductivity(κ)of~0.47 W/(m·K)at low boron nitride nanosheet loading of 2.08 vol.%,which is 2.7 times higher than that of pure epoxy resin.The developed nacre-inspired strategy of layered structure design and interfacial enhancement provides an avenue for fabricating high mechanical properties and thermally conductive polymer nanocomposites.
基金Financial support from the Talent Fund of Beijing Jiaotong University(No,2023XKRC015)the National Natural Science Foundation of China(No.52172081)is gratefully acknowledged.
文摘The high power density and intelligence of next-generation flexible electronic devices bring many challenges to fabricate flexible composite films with electromagnetic interference(EMI)shielding effectiveness(SE)property and excellent toughness via a simple method.Herein,inspired by the layered structure and biopolymer matrix networks in natural nacre,nacre-like layered Ti_(3)C2TX(MXene)/aramid nanofiber(ANF)films were fabricated through sol-gel,vacuum-assisted filtration,and hot-pressing.Three-dimensional(3D)interconnected aramid nanofibers networks between adjacent layered MXene result in an ultralong strain-to-failure of the film.Even though the functional filler MXene contents are as high as 60 wt.%and 70 wt.%,the strain-to-failure of the films could reach astonishing values of 18.34%±1.86%and 14.43%±1.26%,respectively.And the tensile strength could maintain about 85 MPa.Excitingly,with such a high filler,the film can also withstand double folding and vigorous rubbing without damage,which could better adapt to a harsh application environment.The result means that this work provides a convenient way to prepare other high functional filler composite films with excellent mechanical performance.The EMI SE values could reach 45 and 52.15 dB at 60 wt.%and 70 wt.%MXene in 8.2–12.4 GHz.Meanwhile,the films have prominent Joule heating properties,high sensitivity(<15 s),small voltage operation(0.5 V),and high operation constancy(1300 s).Therefore,nacre-inspired MXene/ANF composite films in this work have ability to apply in many areas including communication technology,military,and aerospace.
基金supported by the National Key Research and Development Program of China(2021YFA0715700)the National Natural Science Foundation of China(22075009 and 52350012)+1 种基金National Science Fund for Distinguished Young Scholars(52125302)111 Project(B14009)。
文摘Nacre has inspired research to fabricate tough bulk composites for practical applications using inorganic nanomaterials as building blocks.However,with the considerable pressure to reduce global carbon emissions,preparing nacre-inspired composites remains a significant challenge using more economical and environmentally friendly building blocks.Here we demonstrate tough and conductive nacre by assembling aragonite platelets exfoliated from natural nacre,with liquid metal and sodium alginate used as the “mortar”.The formation of Ga-O-C coordination bonding between the gallium ions and sodium alginate molecules reduces the voids and improves compactness.The resultant conductive nacre exhibits much higher mechanical properties than natural nacre.It also shows excellent impact resistance attributed to the synergistic strengthening and toughening fracture mechanisms induced by liquid metal and sodium alginate.Furthermore,our conductive nacre exhibits exceptional self-monitoring sensitivity for maintaining structural integrity.The proposed strategy provides a novel avenue for turning natural nacre into a valuable green composite.
基金This work was supported by the National Nat- ural Science Foundation of China (51273008, 51473008), and the National Basic Research Program of China (2012CB933200).
基金Acknowledgements The authors thank the financial support by the National Natural Science Foundation of China (No. 51273008 and 51473008), the National High-Tech Research and Development Program (No. 2012AA030305), the National Basic Research Program (No. 2012CB933200), and NSF (No. CMMI-1400274 and AIR-IIP-1343270).
文摘To commercialize fuel cells and metal-air batteries, cost-effective, highly active catalysts for the oxygen reduction reaction (ORR) must be developed. Herein, we describe the development of low-cost, heteroatom (N, P, Fe) ternary-doped, porous carbons (HDPC). These materials are prepared by one-step pyrolysis of natural tea leaves treated with an iron salt, without any chemical and physical activation. The natural structure of the tea leaves provide a 3D hierarchical porous structure after carbonization. Moreover, heteroatom containing organic compounds in tea leaves act as precursors to functionalize the resultant carbon frameworks. In addition, we found that the polyphenols present in tea leaves act as ligands, reacting with Fe ions to form coordination compounds; these complexes acted as the precursors for Fe and N active sites. After pyrolysis, the as-prepared HDPC electrocatalysts, especially HDPC-800 (pyrolyzed at 800℃), had more positive onsets, half-wave potentials, and higher catalytic activities for the ORR, which proceeds via a direct four-electron reaction pathway in alkaline media, similar to commercial Pt/C catalysts. Furthermore, HDPC-X also showed enhanced durability and better tolerance to methanol crossover and CO poisoning effects in comparison to commercial Pt/C, making them promising alternatives for state-of-the-art ORR electrocatalysts for electrochemical energy conversion. The method used here provides valuable guidelines for the design of high-performance ORR electrocatalysts from natural sources at the industrial scale.
基金This work was financially supported by the National Natural Science Foundation of China(No.51925202 and 51972008).
文摘Zn-based batteries have attracted extensive attention due to their high theoretical energy density,safety,abundant resources,environmental friendliness,and low cost.They are a new energy storage and conversion technology with significant development potential and have been widely used in renewable energy and portable electronic devices.Considerable attempts have been devoted to improving the performance of Zn-based batteries.Specifically,battery cycle life and energy efficiency can be improved by electrolyte modification and the construction of highly efficient rechargeable Zn anodes.This review compiles the progress of the research related to Zn anodes and electrolytes,especially in the last five years.This review will introduce fundamental concepts,summarize recent development,and inspire further systematic research for high-performance Zn-based batteries in the future.
基金This work was financially funded by the National Natural Science Foundation of China(Nos.22205247 and 21988102).
文摘In recent years,numerous studies have been reported for oil/water separation,such as superoleophilic materials for oil absorption and underwater superoleophobic membranes for continuous separation.However,for the recovery of oil slick pollution on near-shore ocean surface caused by various reasons,large area and fast availability of used materials are needed to be considered.Herein,we report an efficient and environmentally friendly method to fast process nylon mesh by surface diffuse atmospheric plasma(SDAP)for large-area oil/water separation.Nylon mesh is funcionalized by atmospheric plasma to generate micro/nano composite structures on the surface,resulting in superhydrophilicity and underwater superoleophobicity within only seconds.The pre-wetted modified nylon mesh can achieve high efficiency(>99.9%)and circulating water flux(~30,000 L·m^(-2)·h^(-1)),with high intrusion pressure(~3 kPa)and universality in oil/water separation.Regular plasma unconditionally generated in the atmosphere with the merit of efficiently functionalizing surface has the potential of large-area materials treatment.This study might take one step further for large-area industrial oily wastewater recovery and even oil slicks collection in near-shore water bodies.