摘要：Hydrogen production by photoelectrochemical(PEC) water splitting converts the inexhaustible supply of solar radiation to storable H2 as clean energy and thus has received widespread *** efficiency of PEC water splitting is largely determined by the properties of the ***-dimensional(2 D) layered transition metal dichalcogenides(TMDs) are promising candidates for photoelectrodes due to their atomic layer thickness,tunable bandgap,large specific surface area,and high carrier ***,the construction of 2 D TMDs heterostructures provides freedom in material design,which facilitates the further improvement of PEC water *** review begins by describing the mechanism of PEC water splitting and the advantages of 2 D TMDbased heterostructures for photo ***,the design considerations of the heterostructures for enhanced PEC efficiency are comprehensively reviewed with a focus on material selection,band engineering,surface modification,and long-term ***,current challenges and future perspectives for the development of photoelectrodes based on 2 D TMDs heterostructures are addressed.

摘要：Sustainable polyurethanes prepared from castor oil and diisocyanates show very low strength and toughness, due to the highly cross-linked and flexible structure. Herein, we report a new strategy to simultaneously reinforce and toughen castor oil-based polyurethane via incorporating a stiff component （isosorbide, IS） to enhance network stiffness and reduce crosslink density. The crosslinking degree de- creases while the strength, moduli, ductility and heat re- sistance significantly increase accordingly with increasing IS content. The tensile behaviors are tunable over a broad range （either as elastomers or as plastics） depending on the com- positions. The polyurethanes show excellent thermal stability with onset decomposition temperature higher than 280℃. The investigation provides a new hint for future design and fab- rication of high performance sustainable polymers from other vegetable oils.

摘要：Drug administration customized to individual cells could intrinsically address cancer heterogeneity and provide a safe and effective method for delivering personalized treatment. To accomplish this, we developed a smart nanodrug delivery system characterized by cancer cell-targeted drug delivery and intracellular biomarker-responsive drug activation. This system was composed of a long-nicked DNA duplex formed by tandem hybridization of two extended antisense oligonucleotides whose ends were separately blocked with a cancer cell-specific aptamer, AS1411,and a replaceable anti-biomarker probe(ABP). We demonstrated that this DNA nanodrug was directed to cancer cells with the guidance power of AS 1411 and then activated by the presence of a given intracellular biomarker. By using such a belt-and-braces strategy, this DNA nanodrug system could safely and efficiently accelerate apoptosis of target cancer cells. Moreover, since the expression level of biomarkers tends to indicate the specific physiological state of individual cells, biomarker-responsive activation of the nanodrug is expected to enable customized drug administration at the cellular level.

摘要：With the rapid expansion of the global motor vehicle population,the transportation sector has taken up a growing proportion among all the carbon dioxide emissionrelated *** contribute to solutions of the carbon dioxide-oriented problem in transportation,this paper proposes the“ALL FREE”concept that applies partial oxidation process instead of the conventional complete oxidation to vehicle *** such an engine,the fuels are partially oxidized into corresponding chemical products,which,as a result,enable the process to be theoretically free of CO_(2),while the heat output of the partial oxidation could drive the *** the other hand,the resulting products are of great value,which could decrease or even counteract the cost of fuels in *** this paper,the thermodynamic and kinetic data(e.g.,the heat output and heat release rate)of five selected partial oxidation reactions were calculated at length to demonstrate and exemplify the theoretical feasibility of the“ALL FREE”*** turned out that the partial oxidation of n-butane to maleic anhydride has the most potential to meet the basic requirements of this *** sum up,this design concept is of significant application potential for the reduction of CO_(2)emissions in the transportation industry,although there remain many technical challenges.

摘要：Gas-involving electrochemical reactions,like oxygen reduction reaction (ORR),oxygen evolution reaction (OER),and hydrogen evolution reaction (HER),are critical processes for energy-saving,environment-friendly energy conversion and storage technologies which gain increasing *** development of according electrocatalysts is key to boost their electrocatalytic *** efforts have been put into the development of advanced electrocatalysts to overcome sluggish *** the other hand,the electrode interfaces-architecture construction plays an equally important role for practical applications because these imperative electrode reactions generally proceed at triple-phase interfaces of gas,liquid electrolyte,and solid electrocatalyst.A desirable architecture should facilitate the complicate reactions occur at the triple-phase interfaces,which including mass diffusion,surface reaction and electron *** this review,we will summarize some design principles and synthetic strategies for optimizing triple-phase interfaces of gas-involving electrocatalysis systematically,based on the electrode reaction process at the three-phase *** can be divided into three main optimization directions:exposure of active sites,promotion of mass diffusion and acceleration of electron ***,we especially highlight several remarkable works with comprehensive optimization about specific energy conversion devices,including metal-air batteries,fuel cells,and water-splitting devices are demonstrated with superb *** the last section,the perspectives and challenges in the future are proposed.

摘要：Nanozymes,the functional nanomaterials with enzyme-like activities,have been widely explored for both in vitro and in vivo applications(Wei and Wang,2013;Wu et al.,2019;Huang et al.,2019;Liang and Yan,2019).Particularly,by modulating the levels of reactive oxygen species(ROS)in vivo,numerous therapeutic nanozymes have been developed to treat diseases,ranging from cancer to neurodegenerative diseases(Fan et al.,2018;Kwon et al.,2018).

摘要：A comprehensive understanding of excited-state dynamics of semiconductor quantum dots or nanomaterials at the atomic or molecular level is of scientific *** inorganic(or non-covalently protected)seimiconductor molecular nanoclusters with atomically precise structure are contributive to establish accurate correlation of excited-state dynamics with their composition/structure,however,the related studies are almost blank because of unresolved solvent dispersion ***,we designedly created the largest discrete chalcogenide seimiconductor molecular nanoclusters(denoted P2-CuMSnS,M=In or/and Ga)with great dispersibility,and revealed an interesting intracluster“core–shell”charge transfer relaxation dynamics.A systematic red shift in absorption spectra with the gradual substitution of In by Ga was experimentally and computationally investigated,and femtosecond transient absorption measurements further manifested there were three ultrafast processes in excited-state dynamics of P2 nanoclusters with the corresponding amplitudes directed by composition *** results hold the great promise of the solution-processible applications of semiconductor-NC-based quantum dots and facilitate the development of atomically precise nano-chemistry.

摘要：The uranyl ion(UO22+) poses high risks to human health and the environment, hence its detection and monitoring is of utmost significance. However, the development of an ultra-sensitive, high-efficiency and convenient approach for on-site detection of UO22+ remains a challenge. Herein, a reliable and reusable surface-enhanced Raman spectroscopy(SERS)-based microfluidic biosensor was developed for rapid detection of UO22+ in real samples. The detection protocol involved the reaction of 5′-Rhodamine B(RhB)-labeled double-stranded DNA for UO22+-specific DNAzyme-cleavage reaction in a U-shaped microchannel. Then, the reaction products were delivered into three parallel samples for high-throughput tests by SERS biochips,where 3 D ZnO-Ag mesoporous nanosheet arrays(MNSs) were modified with a single-stranded DNA(ssDNA). The ssDNAwas sequence-complementary with the 5′-RhB-labeled cleaved-stranded DNA(csDNA) from the reaction products. By the hybridization of ssDNA and csDNA, the signal probe RhB was fixed close to the surface of the ZnO-Ag MNSs to enhance the Raman signal. The limit of detection for UO22+ with the microfluidic-SERS biosensor was 3.71×10-15 M. An over 20,000-fold selectivity towards UO22+ response was also achieved in the presence of 15 other metal ions. The high-throughput microfluidicSERS biosensor operated well for practical UO22+ detection, with excellent recoveries in contaminated river and tap water from95.2% to 106.3%(relative standard deviation(RSD)<6.0%, n=6). Although the SERS-based microfluidic biosensor developed in this study was deployed for the detection of UO22+, the reusable and high-efficiency system may be expanded to the detection of other analytes on-site.

摘要：Five polymer bonded explosives(PBXs)with the base explosive epsilon-CL-20(hexanitrohexaazaisowurtzi-tane),the most important high energy density compound(HEDC),and five polymer binders(Estane 5703,GAP,HTPB,PEG,and F_(2314))were *** dynamics(MD)method was employed to investigate their binding energies(E_(bind))< compatibility,safety,mechanical properties,and energetic *** information and rules were reported for choosing better binders and guiding formulation design of high energy density material(HEDM).According to the calculated binding energies,the ordering of compatibility and stability of the five PBXs was predicted as epsilon-CL-20/PEG < epsilon-CL-20/ Estane5703 ≈ epsilon-CL-20/GAP < epsilon-CL-20/HTPB < epsilon-CL-20/F_(2314).By pair correlation function g(r)analyses,hydrogen bonds and vdw are found to be the main interactions between the two *** elasticity and isotropy of PBXs based epsilon-CL-20 can be obviously improved more than pure epsilon-CL-20 *** is not by changing the molecular structures of epsilon-CL-20 for each binder to affect the *** safety and energetic properties of these PBXs are mainly influenced by the thermal capability(C_p^(deg))and density(p)of binders,respectively.

摘要：Porous g-C_(3)N_(4)nanosheets(PCN)were prepared by the nickel-assisted one-step thermal polymerization ***(H2)which was produced by the reaction between nickel(Ni)foam and ammonia(NH3)defined the structure and properties of *** the formation of PCN,the participation of H2 not only enhanced the spacing between layers but also boosted the specific surface area that more active sites were ***,H2 promoted pores formation in the nanosheets,which was beneficial to the transfer of photons through lamellar structure and improved the absorption efficiency of visible ***,the obtained PCN possessed better Cr(Ⅵ)photocatalytic reduction efficiency than pure g-C_(3)N_(4).The reaction rate constant(k)of PCN(0.013 min-1)was approximately twice that of bare g-C_(3)N_(4)(0.007 min-1).Furthermore,the effects of original pH and concentration of Cr(Ⅵ)-containing solution on re moval efficiency of Cr(Ⅵ)were explored.A possible photocatalytic mecha nism was proposed based on the experiments of radical scavengers and photoelectrochemical characterizations.