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Cyclin-dependent kinases 4 and 6 inhibitors (CDK4/6i) have been demonstrated to trigger antitumor immunity for tumor regression. However, the therapeutic performance of CDK4/6i-meadiated cancer immunotherapy was impaired by the immunosuppressive tumor microenvironment (ITM) due to overexpression of programmed death ligand 1 (PD-L1) on the surface of cancer cell membrane. To improve the immunotherapeutic performance of CDK4/6i, we herein developed endosomal acid-activatable micelleplex for siRNA delivery and PD-L1 knockdown in the tumor cells in vitro and in vivo. We further demonstrated that the combination of PD-L1 knockdown and CDK4/6 inhibition facilitated intratumoral infiltration of cytotoxic T lymphocytes (CTLs), and elicited protective immune response and efficiently suppressed tumor growth in vivo. This study revealed the importance of molecular design of the micelleplex for highly efficient siRNA delivery, which might provide a novel insight for RNAi-based cancer immunotherapy.

A appropriate size with three-dimension (3D) channels for lithium diffusion plays an important role in constructing high-performing LiNi0.5Mn1.5O4 (LNMO) cathode materials, as it can not only reduce the transport path of lithium ions and electrons, but also reduce the side effects and withstand the structural strain in the process of repetitive Li+ intercalation/deintercalation. In this work, an efficient method for designing the hollow LNMO microsphere with 3D channels structure by using polyethylene oxide (PEO) as soft template agent assisted solvothermal method is proposed. Experimental results indicate that PEO can make the reagents mingle evenly and nucleate slowly in the solvothermal process, thus obtaining a homogeneous distribution of carbonate precursors. In the final LNMO products, the hollow 3D channels structure obtained by the decomposition of PEO and carbonate precursor in the calcination can provide abundant electroactive zones and electron/ion transport paths during the charge/discharge process, which benefits to improve the cycling performance and rate capability. The LNMO prepared by adding 1 g PEO possesses the most outstanding electrochemical performance, which presented an excellent discharge capacity of 143.1 mAh g−1 at 0.1 C and with a capacity retention of 92.2% after 100 cycles at 1 C. The superior performance attributed to the 3D channels structure of hollow microspheres, which provide uninterrupted conductive systems and therefore achieve the stable transfer for electron/ion.

Potassium-ion batteries are among the most promising candidates to satisfy the large-scale energy storage systems due to their low-cost and abundant potassium sources. However, it is highly desired to seek suitable cathode materials with high capacity and voltage platform, long cycling stability and durability. Transitional metal layered oxides as the most important cathode materials have been widely investigated in lithium-ion batteries and sodium-ion batteries. Recently, transitional metal layered oxides for potassium-ion batteries have aroused huge attention owing to their special structures and potential in applications. Although most transitional metal layered oxides exhibit tolerable capacities, the relationship between structure and electrochemical performance needs further investigation in detail. Herein, the research status and development of transitional metal layered oxides for potassium-ion batteries are summarized in this review. To solve the existing problems of transitional metal layered oxides in potassium-ion batteries, the improvement of air stability and electrochemical performance are also thoroughly discussed. Based on the achievements in recent years, a prospect on the further development of transitional metal layered oxides for potassium-ion batteries is also provided.

Solid polymer electrolytes have been considered as the promising candidates to improve the safety and stability of high-energy lithium metal batteries. However, the practical applications of solid polymer electrolytes are still limited by the low ionic conductivity, poor interfacial contact with electrodes, narrow electrochemical window and weak mechanical strength. Here, a series of novel block copolymer electrolytes with three-dimensional networks are designed by cross-linked copolymerization of the polyethylene glycol soft segments and hexamethylene diisocyanate trimer hard segments. Their ionic migration performances and interface compatibilities with Li metal anode have been optimized delicately by tailoring the ratio of these functional units. The optimized block copolymer electrolyte has shown an amorphous crystalline structure, a high ionic conductivity of ~5.7 × 10−4 S cm−1, high lithium ion transference number (~0.49), wide electrochemical window up to ~4.65 V (vs. Li+/Li) and favorable mechanical strength at 55 °C. Furthermore, the enhanced interface compatibility can well support the normal operations of lithium metal batteries using both LiFePO4 and LiNi0.8Co0.15Al0.05O2 cathodes. This study not only paves a new way to develop solid polymer electrolyte with optimizing functional units, but also provides a polymer electrolyte design strategy for the application demand of lithium metal battery.

Aluminium–sulfur (Al–S) batteries possess high research merits and application prospects owing to their high theoretical energy density, high safety and low cost. However, the deficiency of outstanding cathodes severely limits their electrochemical performance. Herein, a N-doped hierarchical porous carbon material with a surface area of 2513 m2 g−1 has been developed by a soft-template method. The hierarchical pores can provide effective electrolyte transport channels and stably accommodate S nanoparticles, while the N-doped carbon can facilitate charge transfer and anchor aluminium sulfides to improve the electrochemical stability of the cathode. Coupling the S composite cathode with a low-cost AlCl3/acetamide electrolyte, the Al–S battery can deliver a capacity above 1027 mA h g−1 at 0.2 A g−1 for 50 cycles and an excellent cyclability above 483/405 mA h g−1 at 1 A g−1 for 500/700 cycles. In situ Raman spectroscopy and ex situ solid-state nuclear magnetic resonance have been used to monitor the reversible reactions of S and identify the configuration of sulfides, showing that α-type Al2S3 with a tetra-coordinated configuration is the dominant final discharge product. This work sheds light on the design of S composite cathodes and understanding of reaction mechanisms for the fabrication of high-reversibility, high-capacity and low-cost Al–S batteries.

The optimization of anode materials such as Sn, P and Sn4P3 in terms of capacity and cyclability is crucial to improve the overall performance of sodium-ion batteries. However, the delicate fabrication of these materials, including the balanced crystalline/amorphous domains, reasonable particle size and distribution, complementary components exhibiting synergetic reactions, among others, still greatly retards the realization of maximum performance. Herein, a series of Sn/P-based composite materials with a plum pudding configuration were fabricated to achieve controlled crystalline/amorphous structures as well as optimized size and distribution in a carbon framework. By using a facile and low-cost ball milling method, the structural transformation of Sn4P3 into phase-separated crystalline Sn and amorphous P in a carbonaceous framework can be finely controlled, producing a series of binary (Sn4P3/C), quaternary (Sn4P3/Sn/P/C) and ternary (Sn/P/C) composites. Due to the complementary components, crystalline/amorphous adjustment, crystallite sizes and well-integrated interfaces, the quaternary Sn4P3/Sn/P/C composite showed the best electrochemical performance, with a noticeable long-cycle performance of 382 mA h g−1 and 86% capacity retention for nearly 300 cycles. Different from binary and ternary composites, the discharge of quaternary composite generates no noticeable signals of Na15Sn4 and Na3P in the ex-situ X-ray diffraction patterns, suggesting the crystallite growth of sodiation products can be depressed. Moreover, Sn4P3 in the quaternary composite can be partially regenerated in the desodiation reaction, implying the significant short-range interaction and thus better synergetic reactions between Sn and P components. The results demonstrate that the design and organization of crystalline/amorphous structures can serve as an efficient strategy to develop novel electrode materials for sodium ion batteries.

Machine learning-based data-driven models have achieved great success since their invention. Nowadays, the artificial neural network (ANN)-based machine learning methods have made great progress than ever before, such as the deep learning and reinforcement learning, etc. In this study, we coupled the ANN with the K-nearest neighbor method to propose a novel hybrid machine learning (HML) hydrological model for flood forecast purpose. The advantage of the proposed model over traditional neural network models is that it can predict discharge continuously without accuracy loss owed to its specially designed model structure. In order to overcome the local minimum issue of the traditional neural network training, a genetic algorithm and Levenberg–Marquardt-based multi-objective training method was also proposed. Real-world applications of the HML hydrological model indicated its satisfactory performance and reliable stability, which enlightened the possibility of further applications of the HML hydrological model in flood forecast problems.

Mesocrystals, the non-classical crystals with highly ordered nanoparticle superstructures, have shown great potential in many applications because of their newly collective properties. However, there is still a lack of a facile and general synthesis strategy to organize and integrate distinct components into complex mesocrystals, and of reported application for them in industrial catalytic reactions. Herein we report a general bottom-up synthesis of CuO-based trimetallic oxide mesocrystals (denoted as CuO-M1Ox-M2Oy, where M1 and M2 = Zn, In, Fe, Ni, Mn, and Co) using a simple precipitation method followed by a hydrothermal treatment and a topotactic transformation via calcination. When these mesocrystals were used as the catalyst to produce trichlorosilane (TCS) via Si hydrochlorination reaction, they exhibited excellent catalytic performance with much increased Si conversion and TCS selectivity. In particular, the TCS yield was increased 19-fold than that of the catalyst-free process. The latter is the current industrial process. The efficiently catalytic property of these mesocrystals is attributed to the formation of well-defined nanoscale heterointerfaces that can effectively facilitate the charge transfer, and the generation of the compressive and tensile strain on CuO near the interfaces among different metal oxides. The synthetic approach developed here could be applicable to fabricate versatile complicated metal oxide mesocrystals as novel catalysts for various industrial chemical reactions.

Flooding is a major natural disaster that has brought tremendous losses to mankind throughout the ages. Even so, floods can be controlled by appropriate measures to minimize loss and damage. Flood risk assessment is an essential analytic step in preventing floods and reducing losses. Identifying previous flood risk and predicting future features are conducive to understanding the changing patterns and laws of flood risk. Taking the Dongjiang River basin as a study case, we assessed and regionalized flood risk in 1990, 2000, and 2010 from the past perspective and explored dynamic expansion during 1990-2010. Then, we projected land-use type, population, and gross domestic product in 2030 and 2050 and finally assessed and regionalized the risk from a future perspective. Results show that areas with very high risk accounted for 14.98-18.08% during 1990-2010; approximately 13.90% areas of the basin transformed from lower-level risk to higher-level risk whereas 9.07% fell from a higher level to a lower level during the period. For the future scenario, areas with very high and high risk in 2030 and 2050 are expected to account for 21.55% and 24.84%, respectively. Generally, our study can better identify changes in flood risk at a spatial scale and reveal the dynamic evolution rule, which provides a synthetical means of flood prevention and reduction, flood insurance, urban planning, and water resource management in the future under global climate change, especially for developing or high-speed urbanization regions.

The production of large single-crystal metal foils with various facet indices has long been a pursuit in materials science owing to their potential applications in crystal epitaxy, catalysis, electronics and thermal engineering1–5. For a given metal, there are only three sets of low-index facets ({100}, {110} and {111}). In comparison, high-index facets are in principle infinite and could afford richer surface structures and properties. However, the controlled preparation of single-crystal foils with high-index facets is challenging, because they are neither thermodynamically6,7 nor kinetically3 favourable compared to low-index facets6–18. Here we report a seeded growth technique for building a library of single-crystal copper foils with sizes of about 30 × 20 square centimetres and more than 30 kinds of facet. A mild pre-oxidation of polycrystalline copper foils, followed by annealing in a reducing atmosphere, leads to the growth of high-index copper facets that cover almost the entire foil and have the potential of growing to lengths of several metres. The creation of oxide surface layers on our foils means that surface energy minimization is not a key determinant of facet selection for growth, as is usually the case. Instead, facet selection is dictated randomly by the facet of the largest grain (irrespective of its surface energy), which consumes smaller grains and eliminates grain boundaries. Our high-index foils can be used as seeds for the growth of other Cu foils along either the in-plane or the out-of-plane direction. We show that this technique is also applicable to the growth of high-index single-crystal nickel foils, and we explore the possibility of using our high-index copper foils as substrates for the epitaxial growth of two-dimensional materials. Other applications are expected in selective catalysis, low-impedance electrical conduction and heat dissipation. Large-area single-crystal high-index copper and nickel foils with several types of facet are fabricated using mild pre-oxidation of the metal foil surface followed by annealing in a reducing atmosphere.

The sphene-type solid electrolyte with high ionic conductivity has been designed for solid-state lithium metal battery. However, the practical applications of solid electrolytes are still suffered by the low relative density and long sintering time of tens of hours with large energy consumption. Here, we introduced the spark plasma sintering technology for fabricating the sphene-type Li1.125Ta0.875Zr0.125SiO5 solid electrolyte. The dense electrolyte pellet with high relative density of ca. 97.4% and ionic conductivity of ca. 1.44× 10−5 S/cm at 30 °C can be obtained by spark plasma sintering process within the extremely short time of only ca. 0.1 h. Also the solid electrolyte provides stable electrochemical window of ca. 6.0 V(vs. Li+/Li) and high electrochemical interface stability toward Li metal anode. With the enhanced interfacial contacts between electrodes and electrolyte pellet by the in-situ formed polymer electrolyte, the solid-state lithium metal battery with LiFePO4 cathode can deliver the initial discharge capacity of ca. 154 mAh/g at 0.1 C and the reversible capacity of ca. 132 mAh/g after 70 cycles with high Coulombic efficiency of 99.5% at 55 °C. Therefore, this study demonstrates a rapid and energy efficient sintering strategy for fabricating the solid electrolyte with dense structure and high ionic conductivity that can be practically applied in solid-state lithium metal batteries with high energy densities and safeties.

Drug delivery systems (DDSs) are of paramount importance to deliver drugs at the intended targets, e.g., tumor cells or tissue by prolonging blood circulation and optimizing the pharmaceutical profiles. However, the therapeutic efficacy of DDSs is severely impaired by insufficient or non-specific drug release. Dynamic chemical bonds having stimuli-liable properties are therefore introduced into DDSs for regulating the drug release kinetics. This review summarizes the recent advances of dynamic covalent chemistry in the DDSs for improving cancer therapy. The review discusses the constitutions of the major classes of dynamic covalent bonds, and the respective applications in the tumor-targeted DDSs which are based on the different responsive mechanisms, including acid-activatable and reduction-activatable. Furthermore, the review also discusses combination strategies of dual dynamic covalent bonds which can response to the complex tumor microenvironment much more accurately, and then summarizes and analyzes the prospects for the application of dynamic covalent chemistry in DDSs.

Different from the grain boundary diffusion process (GBDP), which is suitable for modifying thin magnet, a green-pressing agents permeation process (GAPP) that uses low melting point alloys was applied to the Nd-Fe-B green compact with a thickness over 15 mm to reconstruct the boundary microstructure of a sintered Nd-Fe-B magnet. The coercivity increases from 12.3 kOe for the sample free of Pr80Al20 to 16.8 kOe for the sample with 2 wt% Pr80Al20. By further increasing the Pr80Al20 content to 3 wt%, the coercivity increases slightly, but the remanence and Hk/Hcj deteriorate obviously. The optimal comprehensive properties of Hcj = 16.8 kOe, Br = 13.4 kG and Hk/Hcj = 0.975 are obtained at 2 wt% Pr80Al20, since matrix phase grains are separated by relatively continuous thin grain boundary layers, which weaken the magnetic coupling between adjacent grains. The coercivities of the samples from the GAPP that use 2 wt% Pr80Al20, Pr70Cu30 and Pr60Tb20Al20 alloys, respectively, can be enhanced to a large extent. However, the coercivity of the magnet reconstructed with Pr80Al20 is lower than that of the sample with Pr60Tb20Al20 but is higher than that of the sample reconstructed with Pr70Cu30 alloy. Moreover, the coercivity of the sample from the GAPP using 2 wt% Pr80Al20 is much higher than that of the sample from the GBDP, which is due to a nearly uniform boundary microstructure from the surface to the interior of the thick magnet from the GAPP, thus providing new insights into the fabrication of thick and bulky permanent magnets with high coercivity.

Traditional technologies for the recycling of spent lithium-ion batteries (LIBs) mainly focus on reductive leaching, which often leads to total leaching rather than selective leaching of metals. As...

The importance of the immune system in cancer therapy has been reaffirmed by the success of the immune checkpoint blockade. The complex tumor microenvironment and its interaction with the immune system, however, remain mysteries. Molecular imaging may shed light on fundamental aspects of the immune response to elucidate the mechanism of cancer immunotherapy. In this review, we discuss various imaging approaches that offer in-depth insight into the tumor microenvironment, checkpoint blockade therapy, and T cell-mediated antitumor immune responses. Recent advances in the molecular imaging modalities, including magnetic resonance imaging (MRI), positron electron tomography (PET), and optical imaging (e.g., fluorescence and intravital imaging) for in situ tracking of the immune response, are discussed. It is envisaged that the integration of imaging with immunotherapy may broaden our understanding to predict a particular antitumor immune response.

Although considerable effort has been devoted to purifying nitrogen oxides (NOx), it is still challenging to effectively reduce NOx at room temperature and ambient pressure without catalysts. In this study, as a proof-of-concept, we have for the first time demonstrated the room-temperature reduction of nitrogen dioxide (NO2) using a rechargeable lithium-nitrogen dioxide (Li-NO2) battery. The battery shows a capacity of 884 mAh g−1 at 50 mA g−1 (an actual energy density of 666 Wh kg−1) and a promising electrochemical Faraday efficiency (FE) of 67%. The unique properties of Li-NO2 rechargeable batteries not only provide a way to reduce and recycle NO2 but also highlight the potential of oxidative air pollutants as energy sources for next-generation electrochemical energy storage (EES) systems.

Micro computed tomography (µCT) allows the noninvasive visualization and 3D reconstruction of internal structures of objects with high resolution. However, the current commercial µCT system relatively rotates the source-detector or objects to collect projections, referred as RCT in this paper, and has difficulties in imaging large objects with high resolutions because fabrication of large-area, inexpensive flat-panel detectors remains a challenge. In this paper, we proposed a source translation based CT (STCT) for imaging large objects with high resolution to get rid of the limitation of the detector size, where the field of view is primarily determined by the source translation distance. To compensate for the deficiency of incomplete data in STCT, we introduced multi-scanning STCT (mSTCT), from which the projections theoretically meet the conditions required for accurate reconstructions. Theoretical and numerical studies showed that mSTCT has the ability to accurately image large objects without any visible artifacts. Numerical simulations also indicated that mSTCT has a potential capability to precisely image the region of interest (ROI) inside objects, which remains a challenge in RCT due to truncated projections. In addition, an experimental platform for mSTCT has been established, from which the 2D and 3D reconstructed results demonstrated its feasibility for µCT applications. Moreover, STCT also has a great potential for security inspection and product screening by using two perpendicular STCTs, with advantages of low-cost equipment and high-speed examination.

The accurate detection of tumorous methylglyoxal (MGO) and its detoxifier glyoxalase 1 (GLO1) in living systems is critical for understanding their roles in tumor initiation and progression. To date, the in situ fluorescence detection of endogenous MGO and GLO1 in tumor has not been reported. Herein we developed a near-infrared (NIR) fluorescent probe MEBTD to specifically detect tumorous MGO. Compared with previously reported MGO fluorescent probes, MEBTD exhibits several distinct advantages, including NIR emission, high selectivity with an MGO detection limit of 18 nM, and a 131-fold off-on ratio. The probe could sense GLO1 activity and monitor the therapeutic effect of GLO1 inhibitors by imaging tumorous MGO in a both a real-time and in situ manner, demonstrating that the biological effect of GLO1 inhibitors is dependent on the GLO1 activity. Furthermore, MEBTD enables the visualization of tumorous MGO induced by GLO1 inhibitors in vivo. To the best of our knowledge, MEBTD is the first NIR fluorescent probe for specifically imaging tumorous MGO in living animals, indicating the promising potential for tumor diagnosis and therapeutic evaluation.

Aluminum-sulfur (Al-S) battery is a promising candidate of next generation rechargeable batteries owing to its high theoretical energy density, high safety and low cost, but currently greatly impeded by the shortage of high-performance and cost-effective electrolytes. In this work, a low-cost deep eutectic solvent, i.e., AlCl3/acetamide, as the electrolyte for reversible room-temperature Al-S battery has been reported. The Al-S battery delivers an initial capacity above 1500 mA h g−1 and good rate performance, which is most probably caused by the presence of AlCl4−, Al2Cl7− and [AlCl2·(acetamide)2]+ ions as indicated by spectroscopic analysis. Furthermore, X-ray photoelectron spectroscopy on the discharged sulfur cathode suggests the presence of aluminum sulfides including Al2S3 as electrochemical conversion products. Density functional theory calculations on the energy barriers provide insights into the electrochemical reaction pathways. This AlCl3/acetamide based Al-S battery presents a promising prospect for high-performance and low-cost energy storage system in future.

The development of silicon-based anode materials is important for improving the energy density of current lithium ion batteries. However, there are still strong demands for these materials with better cycle stability and higher reversible capacity. Here, a kind of dual bond restricted MXene-Si-CNT composite anode materials with enhanced electrochemical performance is reported. These dual bonds have been clearly revealed by an X-ray photoelectron spectroscopy technique and also proven by theoretical calculations with spontaneous reaction energy values (-0.190 and -0.429 eV/atom for Ti-Si and C-Si bonds, respectively). The cycle stability of the composites, prepared by a facile ball-milling synthetic method, can obviously be improved because of the existence of these dual bonds and the multidimensional constructed architecture. The MXene-Si-CNT composite with 60 wt % silicon possesses the best overall performance, with ∼80% capacity retention after 200 cycles, and achieves 841 mAh g-1 at 2 A g-1. This approach demonstrates a promising strategy to exploit high-performance anode materials and lessens the immanent negative effect of silicon-based materials. Furthermore, it is significant to extend this method to other anode materials with serious volumetric change problems during the cycling process.

The mechanism research of structure-related reactions on Li2MnO3 is important to enhance the electrochemical performance of lithium-manganese-rich layered oxides. Although there are some reports on the structure evolution of Li2MnO3 during cycling process, the employed research techniques are very limited, mainly in/ex-situ X-ray diffraction, X-ray absorption and transmission electron microscopy. Here, atomic pair distribution function, a method to study the local atomic arrangement on the basis of average spectroscopic information, is used for the first time to study the local structure evolution of Li2MnO3 during electrochemical charge/discharge cycles. The results clearly demonstrate that Mn3+/Mn4+ redox couple is activated and Mn ions are reduced during discharging process. Some Mn ions in Mn layers can significantly migrate to Li layers and occupy the octahedral sites. As a result, a portion of inserted Li ions can occupy the face-shared tetrahedron sites, accompanied by the formation of local spinel-like structure. This work provides an important and suitable method based on the average spectroscopic information to investigate the local structure of electrode materials of lithium-ion batteries as well as other advanced battery systems.

Ionic liquids, defined here as room-temperature molten salts, composed mainly of organic cations and (in)organic anions ions that may undergo almost unlimited structural variations with melting points below 100 °C. They offer a unique series of physical and chemical properties that make them extreme important candidates for several energy applications, especially for clean and sustainable energy storage and conversion materials and devices. Ionic liquids exhibit high thermal and electrochemical stability coupled with low volatility, create the possibility of designing appropriate electrolytes for different type batteries and supercapacitors. Herein, varieties of ionic liquids applications are reviewed on their utilization as electrolytes for Li-ion batteries, Na-ion batteries, Li-O2(air) batteries, Li-Sulfur (Li-S) batteries, supercapacitors and as precursors to prepare and modify the electrode materials, meanwhile, some important research results in recent years are specially introduced, and the perspective on novel application of ionic liquids is also discussed.

Lithium metal anode is considered one of the most promising anode materials for lithium rechargeable batteries due to its highest theoretical specific capacity and lowest anode potential. However, dendritic growth during Li planting leads a safety concern and hinders the application of lithium (Li) metal batteries. Herein, unique 3D nanoporous/macroporous structure conductive Cu was designed and used as the current collector for Li planting/stripping to regulate metal Li deposition and inhibit the growth of lithium dendrite. The nanoporous/macroporous Cu current collector can effectively reduce the local current density and guide the metallic Li nucleation, leading Li to deposit uniformly on its surface. As a result, the modified Li@nanoporous/macroporous Cu current collector composite anode possesses a dendrite-free morphology and an enhanced cycling stability with a high average Coulombic efficiency of 98% for 400 h. When matching the LiFePO4 cathode, the LiFePO4 and Li@porous Cu current collector anode resultant full cell exhibits stable cycling performance.

We report herein a nanocomposite that has a continuous phase of amorphous calcium carbonate (ACC) filled with fluorescent carbon quantum dots (CDs) and undergoes phase transitions triggered by changes in moisture content in organic solvents. The phase transitions involve aggregation of the nanocomposite particles (in the order of 20 nm) and crystallization of the ACC phase, expelling the CDs from the composite and generating fluorescent signals at the same time. This can be triggered with a moisture content as low as 15 ppm, and the intensity of the fluorescent signal can be correlated quantitatively with a moisture content of up to 100%.

In this study, a novel acyl chloride monomer trimellitic anhydride chloride (TAC) with an anhydride group was blended with trimesoyl chloride (TMC) as organic phase monomers to fabricate high-flux nanofiltration membranes. Due to the reaction activity differences of organic phase monomers (TMC and TAC) with piperazine, the chemical compositions and structures of polyamide active layer could be tailored through varying the TAC content. It was found that the participation of TAC could yield a looser polyamide separation layer on the polysulfone support membrane, along with an increased surface roughness, hydrophilicity, pore size and negative charge density. As a result, the resultant membrane exhibited excellent water-salt separation. When the TAC concentration was increased to 0.04 wt%, the optimized membrane exhibited a high pure water permeability (PWP) of 13.2 L m−2 h−1 bar−1, up to 2-fold, in comparison with the pristine membrane, whereas the salt rejections of Na2SO4, MgSO4 and NaCl were 97.6%, 92.7%, and 34.0%, respectively. This work provided a novel and facile strategy to develop high-flux NF membrane.

This study mainly evaluated and compared satellite-based quantitative precipitation estimate products (QPEs) for the drought monitoring of mainland China. Two long-term (more than 30 a) satellite-based QPEs, i.e. the Precipitation Estimation from Remotely Sensed Information using Artificial Neural Networks-Climate Data Record (PERSIANN-CDR) and the Climate Hazards Group InfraRed Precipitation with Station (CHIRPS), and a short-term (18a) QPE, i.e. the Tropical Rainfall Measuring Mission (TRMM) Multi-Satellite Precipitation Analysis (TMPA) 3B42V7 are considered. Two widely used drought indices, the Standardized Precipitation Index (SPI) and the Palmer Drought Severity Index (PDSI), are chosen to evaluate the drought monitoring utility. The 3B42V7 was only evaluated with PDSI due to the short data records. The results show that all the three QPEs perform satisfactorily in the eastern part of China when using both SPI and PDSI. However, their performances for west China could not be clearly determined due to the sparse gauge networks. 3B42V7 features best performance among the three QPEs in the evaluation using PDSI. To further spatiotemporally evaluate the drought utility of the QPEs, four typical drought-affected regions, i.e. northeast China (NEC), Huang-Huai-Hai plain (3HP), southwest China (SWC), and Loess plateau (LP) were extracted from mainland China for specific case studies. Temporally, all three QPEs are able to detect the typical drought of the four regions with both SPI and PDSI, and 3B42V7 presents the least deviation in PDSI estimate. Spatially, both CHIRPS and 3B42V7 accurately catch the spatial centers and extent of the typical drought events, while PERSIANN-CDR could not match the spatial patterns of drought events well. Generally, the long-term PERSIANN-CDR and CHIRPS perform satisfactorily in drought detection and are suitable for drought utility; however, caution should be applied when studying the spatial variation of drought using PERSIANN-CDR. CHIRPS could also be suitable for near-real-time drought monitoring for its shorter time latency of data release. The short-term 3B42V7 also performs well in many cases, and has thus considerable potential for drought monitoring.

By using a low-cost, ternary AlCl3/LiCl/KCl inorganic molten salt as the electrolyte, an aluminum ion battery is able to work stably below 100 °C. When intergrated with a graphite paper cathode, the battery exhibits close performance and similar electrochemical transformations to inorganic electrolyte-based batteries operating at ≥120 °C.

For the time-fractional phase field models, the corresponding energy dissipation law has not been settled on both the continuous level and the discrete level. In this work, we shall address this open issue. More precisely, we prove for the first time that the time-fractional phase field models indeed admit an energy dissipation law of an integral type. In the discrete level, we propose a class of finite difference schemes that can inherit the theoretical energy stability. Our discussion covers the time-fractional gradient systems, including the time-fractional Allen-Cahn equation, the time-fractional Cahn-Hilliard equation, and the time-fractional molecular beam epitaxy models. Numerical examples are presented to confirm the theoretical results. Moreover, a numerical study of the coarsening rate of random initial states depending on the fractional parameter $\alpha$ reveals that there are several coarsening stages for both time-fractional Cahn-Hilliard equation and time-fractional molecular beam epitaxy model, while there exists a $-\alpha/3$ power law coarsening stage., Comment: 21 pages, 6 figures, to appear on SIAM Sci. Comput

Theranostics 9(26), 7981-8000 (2019). doi:10.7150/thno.37568, Published by Ivyspring, Wyoming, NSW

Na2TiSiO5 is investigated as a novel anode of the lithium ion battery for the first time. The low working potential (above 0.1 V) and high capacity (>300 mA h g-1) give this material a high energy density, along with improved safety. After 100 cycles, the capacity retention remains at 94%. Furthermore, possible Li+-occupied sites and the migration path in the Na2TiSiO5 structure are also calculated and discussed in this work.

The tumor immune microenvironment (TIME) is comprised of a complex milieu that contributes to stunting antitumor immune responses by restricting T cells to accumulate in the vicinity of the tumor. Nanomedicine-based strategies are being proposed as a salvage effort to reinvigorate antitumor immunity. Various strategies, however, often fail to unleash the antitumor immune response because of the paucity of appropriate therapeutic targets in the complex TIME, invigorating a fervor of investigation into mechanisms underlying the TIME to resist nanomedicines. In this review article, effective nano/biomaterial-based delivery and TIME normalization approaches that promote T cell-mediated antitumor immune response will be discussed, with a focus on emerging preclinical and clinical strategies for immune normalization. Based on currently available evidence, it seems as if the ultimate success of cancer immunotherapy and nanomedicine hinges on the capacity to normalize the TIME. Here, how nanomedicines target immunosuppressive cells and signaling pathways to broaden the impact of cancer immunotherapy are explored. Acquisition of the urgently needed knowledge of nanomedicine-mediated immune normalization will guide researchers and scientists towards clinical applications of cancer immunotherapy.

The low immunogenicity, insufficient infiltration of T lymphocytes, and dismal response to immune checkpoint blockade therapy pose major difficulties in immunotherapy of pancreatic cancer. Photoimmunotherapy by photodynamic therapy (PDT) can induce an antitumor immune response by triggering immunogenic cell death in the tumor cells. Notwithstanding, PDT‐driven oxygen consumption and microvascular damage can further aggravate hypoxia to exaggerates glycolysis, leading to lactate accumulation and immunosuppressive tumor microenvironment. Herein, a supramolecular prodrug nanoplatform codelivering a photosensitizer and a prodrug of bromodomain‐containing protein 4 inhibitor (BRD4i) JQ1 for combinatory photoimmunotherapy of pancreatic cancer are demonstrated. The nanoparticles are fabricated by host–guest complexation between cyclodextrin‐grafted hyaluronic acid (HA‐CD) and adamantine‐conjugated heterodimers of pyropheophorbide a (PPa) and JQ1, respectively. HA can achieve active tumor targeting by recognizing highly expressed CD44 on the surface of pancreatic tumors. PPa‐mediated PDT can enhance the immunogenicity of the tumor cells and promote intratumoral infiltration of the cytotoxic T lymphocytes. Meanwhile, JQ1 combats PDT‐mediated immune evasion through inhibiting expression of c‐Myc and PD‐L1, which are key regulators of tumor glycolysis and immune evasion. Collectively, this study presents a novel strategy to enhance photoimmunotherapy of the pancreatic cancer by provoking T cells activation and overcoming adaptive immune resistance., Supramolecular prodrug nanosystem composed of β‐cyclodextrin‐grafted hyaluronic acid and reduction‐activatable adamantine‐JQ1/adamantine‐Pheophorbide A conjugates is reported. The prodrug nanoparticle induces immunogenic cell death in the pancreatic tumor cells under near‐infrared laser irradiation, and consequently promoted intratumoral infiltration of the cytotoxic T lymphocytes. Meanwhile, JQ1 relieves glycolysis‐mediated immune evasion and photodynamic therapy‐triggered PD‐L1 overexpression for durable regression of the pancreatic tumor.

Molten-salt assisted solid-state synthesis is considered a promising method in obtaining layer-structured cathodes for lithium-ion batteries with homogeneous elemental distribution and controllable morphologies. However, drawbacks like resource wasting which have arisen from redundant salt removal after sintering greatly hinder the broader application of this technique. In this paper, a closed-loop utilization of molten salts is proposed for the first time with specific electrochemical properties of the products studied. Results confirm the feasibility of this strategy, and that with only replenishing LiOH, the recycled LiOH-LiCl molten salts can be successfully reused into another LiNi0.5Co0.2Mn0.3O2 synthesis, which exhibits almost equal electrochemical performance to the product using fresh molten salts. We believe this research can provide significant insight in guiding green and environmental-friendly preparation methods involving molten salts.

Colorectal cancer (CRC) ranks as the third common and the fourth lethal cancer type worldwide. Immune checkpoint blockade therapy demonstrates great efficacy in a subset of metastatic CRC patients, but precise activation of the antitumor immune response at the tumor site is still challenging. Here a versatile prodrug nanoparticle for second near-infrared (NIR-II) fluorescence imaging-guided combinatory immunotherapy of CRC is reported. The prodrug nanoparticles are constructed with a polymeric oxaliplatin prodrug (PBOXA) and a donor-spacer-acceptor-spacer-donor type small molecular fluorophore TQTCD. The later displays large Stokes shift (>300 nm), fluorescence emission over 1000 nm, and excellent photothermal conversion performance for NIR-II fluorescence imaging-guided photothermal therapy (PTT). The prodrug nanoparticles show seven times higher intratumoral OXA accumulation than free oxaliplatin. TQTCD-based PTT and PBOXA-induced chemotherapy trigger immunogenic cell death of the tumor cells and elicit antitumor immune response in a spatiotemporally controllable manner. Further combination of the prodrug nanoparticle-based PTT/chemotherapy with programmed death ligand 1 blockade significantly promotes intratumoral infiltration of the cytotoxic T lymphocytes and eradicates the CRC tumors. The NIR-II fluorescence imaging-guided immunotherapy may provide a promising approach for CRC treatment.

We propose and analyze a linearly stabilized semi-implicit diffusive Crank--Nicolson scheme for the Cahn--Hilliard gradient flow. In this scheme, the nonlinear bulk force is treated explicitly with two second-order stabilization terms. This treatment leads to linear elliptic system with constant coefficients and provable discrete energy dissipation. Rigorous error analysis is carried out for the fully discrete scheme. When the time step-size and the space step-size are small enough, second order accuracy in time is obtained with a prefactor controlled by some lower degree polynomial of $1/\varepsilon$. {Here $\varepsilon$ is the thickness of the interface}. Numerical results together with an adaptive time stepping are presented to verify the accuracy and efficiency of the proposed scheme., arXiv admin note: text overlap with arXiv:1710.03604, arXiv:1708.09763

Immunotherapy aiming to harness the exquisite power of the immune system has emerged as a crucial part of clinical cancer management. However, only a subset of cancer patients responds to current immunotherapy because of low immunogenicity of the tumor cells and immunosuppressive tumor microenvironment. Herein, host–guest prodrug nanovectors are reported for active tumor targeting and combating immune tolerance in tumors. The prodrug nanovectors are designed by integrating hyaluronic acid (HA) and reduction‐labile heterodimer of Pheophorbide A (PPa) and NLG919 into the supramolecular nanocomplexes, where PPa and NLG919 act as a photosensitizer and potent inhibitor of indoleamine 2,3‐dioxygenase 1 (IDO‐1), respectively. Meanwhile, HA is employed to achieve active tumor targeting by recognizing CD44 overexpressed on the surface of tumor cell membranes. Near infrared (NIR) laser irradiation triggers the release of reactive oxygen species to provoke antitumor immunogenicity and intratumoral infiltration of cytotoxic T lymphocytes (CTLs). Meanwhile, the immunosuppressive tumor microenvironment (ITM) is reversed by NLG919‐mediated IDO‐1 inhibition. Combination of photodynamic immunotherapy and IDO‐1 blockade efficiently eradicates CT26 colorectal tumors in the immunocompetent mice. The host–guest nanoplatform capable of eliciting effective antitumor immunity by inactivating inhibitory immune response can be applied to other immune modulators for improved cancer immunotherapy., Host–guest prodrug nanovectors integrating hyaluronic acid, and heterodimer of NLG919 and Pheophorbide A are reported for photodynamic immunotherapy of cancer. The combination of prodrug nanovector with near infrared laser irradiation triggers the generation of reactive oxygen species for eliciting antitumor immunogenicity and intratumoral infiltration of cytotoxic T lymphocytes (CTLs). Meanwhile, NLG919 activates the CTLs by relieving the immunosuppressive tumor microenvironment.

The Mann-Kendall (MK) statistical test has been widely applied in the trend detection of the hydrometeorological time series. Previous studies have mainly focused on the null hypothesis of “no trend” or the “Type I Error”. However, few studies address the capability of the MK test to successfully recognize the trends. In some cases, especially when the trend test is jointly applied with hydropower station design, flood risk assessment, and water quality evaluation, the “Type II error” is equally important and should not be neglected. To cope with this problem, we carry out Monte Carlo simulations and the results indicate that in addition to the significance level and the sample length, the MK test power has a close relationship with the sample variance and the magnitude of the trend. For a given time series with fixed length, the power of the MK test increases as the slope increases and declines with increasing sample variance. A deterministic relationship between the slope and the standard deviation of the white noise that can be used for evaluating the power of the MK test has also been detected. Furthermore, we find that a positive autocorrelation contained in the time series will increase both the Type I and the Type II errors due to the enlargement of the variance in the MK statistics. Finally, we recommend that researchers slightly increase the significance level and lengthen the time series sample to improve the power of the MK test in future studies.

Lithium-rich layered oxides have been considered as the most promising candidate for offering a high specific capacity and energy density for lithium-ion batteries. However, their practical applications are still suffered by the cycle instability and also closely related thermal stability. Here, microsized crystalline grains with good dispersion of lithium-rich layered oxides are prepared by a molten-salt method, while a spinel structure is also introduced on a grain surface by following chemical oxidation and annealing process, and their thermal performance with different cutoff voltages during the charge process is systematically studied using differential scanning calorimetry method. Results have shown that thermal stability of microsized crystalline grains is better than that of spherical secondary agglomerates, the spinel structure introduction on the grain surface of microsized crystalline grains can contribute obviously to their thermal stability, in which the onset temperature of the exothermic peak has been increased by 103 °C, and the thermal release value can be reduced as much as about 40% when the battery was charged to 4.8 V. Furthermore, the electrochemical performance, especially cycle stability under a high temperature, has also been enhanced for spinel-modified microsized crystalline grains. This work not only develops the microsized crystalline grains with good dispersion of lithium-rich layered oxides, confirming the advantages of these materials compared to spherical secondary agglomerates, but also reveals the method to improve their thermal stability by grain surface structure modification, opening the way to optimize the comprehensive performance of electrode materials for batteries.

Structural modulation endows electrochemical hybrids with promising energy storage properties owing to their adjustable interfacial and/or electronic characteristics. For MXene-based materials, however, the facile but effective strategies for tuning their structural properties at nanoscale are still lacking. Herein, 3D crumpled S-functionalized Ti3 C2 Tx substrate is rationally integrated with Fe3 O4 /FeS heterostructures via coprecipitation and subsequent partial sulfurization to induce a highly active and stable electrode architecture. The unique heterostructures with tuned electronic properties can induce improved kinetics and structural stability. The surface engineering by S terminations on the MXene further unlocks extra (pseudo)capacitive lithium storage. Serving as anode for lithium storage, the optimized electrode delivers an excellent long-term cycling stability (913.9 mAh g-1 after 1000 cycles at 1 A g-1 ) and superior rate capability (490.4 mAh g-1 at 10 A g-1 ). Moreover, the (de)lithiation pathways associated with energy storage mechanisms are further revealed by operando X-ray diffraction, in situ electroanalytical techniques, and first-principles calculations. The hybrid electrode is proved to undergo stepwise phase transformations during discharging but a relatively uniform reconversion during charging, suggesting an asymmetric conversion mechanism. This work provides a novel strategy for designing high-performance hybrids and paves the way for in-depth understanding of complex lithium intercalation and conversion reactions.

Revealing the position of materials with chemical selectivity at atomic scale within functional nanoparticles is essential to understand and control their performance and cutting-edge atom probe tomography is a powerful tool to undertake this task. In this paper, we demonstrate three effective methods to prepare the needle-shaped specimens required for atom probe tomography measurements from nanoparticles of different sizes and provide examples of how atom probe can be used to provide data that is critical to their functionality. Samples measured include lithium-ion batteries (LIBs) cathode nanoparticles (300 - 500 nm), nickel-doped silicon dioxide (Ni@SiO2) catalytic nanoparticles (100 - 200 nm) and tin-doped copper (Sn@Cu) catalytic nanoparticles (

Lithium-rich layered oxide materials are extremely important for improving the energy density of lithium-ion batteries. However, the electrochemical kinetics and cycle stability of these materials ...

Cathodes of lithium-rich layered oxides for high-energy Li-ion batteries in electrically powered vehicles are attracting considerable attention by the research community. However, current research is insufficient to account for their complex reaction mechanism and application. Here, the structural evolution of lithium–manganese-rich layered oxides at different temperatures during electrochemical cycling has been investigated thoroughly, and their structural stability has been designed. The results indicated structure conversion from the two structures into a core–shell structure with a single distorted-monoclinic LiTMO2 structure core and disordered-spinel/rock salt structure shell, along with lattice oxygen extraction and lattice densification, transition- metal migration, and aggregation on the crystal surface. The structural conversion behavior was found to be seriously temperature sensitive, accelerated with higher temperature, and can be effectively adjusted by structural design. This study clarifies...

All-solid-state sodium batteries are promising candidates for the next generation of energy storage with exceptional safety, reliability and stability. The solid electrolytes are key components for enabling all-solid-state sodium batteries with high electrochemical performances. This Review discusses the current developments on inorganic and organic sodium ions solid electrolytes, including β/β′′-alumina, NASICON, sulfides, polymers and others. In particular, the structures, ionic conductivities and fabrications as well as electrochemical/chemical stabilities of solid electrolytes are discussed. The effective approaches for forming intimate interfaces between solid electrolytes and electrodes are also reviewed. And perspectives on future developments in the field of solid electrolytes and possible directions to improve interfacial contacts for future practical applications of all-solid-state sodium batteries are included.

The Jinchang gold deposit has been extensively studied, but precise dates for its formation are debated. Native gold mainly occurs as inclusions within pyrite and quartz. In this study, we analysed quartz crystals coeval with gold precipitation from two different types of mineralization using the ArgusVI multi-collector noble gas mass spectrometer by the stepwise crushing technique to resolve the timing and genesis of gold mineralization. 40Ar/39Ar dating of quartz samples (J12Q) from breccia ore yields a plateau age of 109.87 ± 0.86 Ma, and an inverse isochron age of 109.87 ± 0.88 Ma. Quartz samples (J18Q) from vein ore yields a slightly younger plateau age of 107.76 ± 0.85 Ma, with an inverse isochron age of 107.76 ± 0.92 Ma. These dates place the ore-forming age of the Jinchang gold deposit at 107~110 Ma, much younger than previously published radiometric ages, suggesting the gold mineralization is spatio-temporally associated with the granite porphyry. The formation of the Jinchang gold deposit is consistent with the regional late Mesozoic porphyry-epithermal gold mineralization event in the Yanbian-Dongning area. Finally, our study shows that 40Ar/39Ar of quartz can be used as a powerful tool to date the formation ages of hydrothermal ore deposits.

To evaluate the accuracy and applicability of the TMPA 3B42-V7 precipitation product for the Lancang River basin, we used different statistical indices to explore the performance of the product in comparison to gauge data. Then, we performed a hydrologic simulation using the Variable Infiltration Capacity (VIC) hydrological model with two scenarios (Scenario I: streamflow simulation using gauge-calibrated parameters; Scenario II: streamflow simulation using 3B42-V7-recalibrated parameters) to verify the applicability of the product. The results of the precipitation analysis show good accuracy of the V7 precipitation data. The accuracy increases with the increase of both space and time scales, while time scale increases cause a stronger effect. The satellite can accurately measure most of the precipitation but tends to misidentify non-precipitation events as light precipitation events (

Bismuth-sulfosalts and -tellurides are commonly present in many hydrothermal gold deposits and can provide important genetic and physicochemical constraints on the metallogenesis. The abundant auriferous specular hematite veins in the Yaoan gold deposit of the Jinshajiang-Red River alkaline porphyry metallogenic belt (southwest China) contain an assemblage of Bi-sulfosalts and tellurides together with hematite, pyrite, and chalcopyrite. Bismuth-sulfosalts are characterized by replacement textures resulting from changes of fluid composition (e.g., Pb, Bi, Cu, and Ag) and mainly include bismuthinite derivatives (e.g., bismuthinite, paarite, krupkaite, lindstromite, and friedrichite-aikinite), paděraite, cuprobismutite homologues (probably submicroscopic intergrowths of hodrushite and cuprobismutite), and emplectite. Tellurides are tiny, comprising tsumoite, melonite, hessite, and calaverite, which coexist with bismuthinite derivatives. These Bi-sulfosalts and tellurides have direct contact with gold, indicating that the Yaoan gold metallogenesis was likely linked to the syenite porphyry magmatism that was originally sourced from a regional lithospheric mantle probably metasomatized by subduction of Te-rich sediments. The telluride assemblage also reveals that the gold was precipitated under oxidizing conditions that has a high tellurium fugacity at the beginning (fTe2 = ∼10−7.9 and fS2 = ∼10−8.5 at ∼300 °C).

To accurately monitor the variations of lysosomal nitric oxide (NO) under physiological condition remains a great challenge for understanding the biological function of NO. Herein, we developed a new chemotype probe, namely, MBTD, for acid-promoted and far-red fluorescence imaging of lysosomal NO in vitro and ex vivo. MBTD was rationally designed by incorporating o-phenylenediamino (OPD) moiety into the donor-acceptor-donor (D-A-D) type fluorophore based on a dual intramolecular charge transfer (ICT) mechanism. Compared to previously reported OPD-based NO probes, MBTD displays several distinct advantages including large stroke shift, huge on-off ratio with minimal autofluorescence, and high NO specificity. Particularly, MBTD exhibits an acid-promoted response to NO with high acid tolerance, which greatly improves the spatial resolution to lysosomal NO by excluding the background noise from other nonacidic organelles. Furthermore, MBTD displayed much longer-lived and more stable fluorescence emission in comparison with the commercialized NO probe. MBTD was employed for ratiometric examination of the exogenous or endogenous NO of macrophages. More importantly, MBTD was able to detect the variation of lysosomal NO level in an acute liver injury mouse model ex vivo, implying the potential of MBTD for real-time monitoring the therapeutic efficacy of drug candidates for the treatment of acute liver injury. MBTD as a novel type of NO probe might open a new avenue for precisely sensing lysosomal NO-related pathological and therapeutic process.

The rechargeable Li–CO2 battery has attracted much attention for energy storage because of the high energy density and efficient utilization of greenhouse gas. However, it’s still suffered by low safety issue of liquid electrolyte. Herein, a composite cathode consisting of CNTs and polymer electrolytes was fabricated by the in-situ polymerization process for the polymer electrolyte-based solid-state Li–CO2 batteries. With the good dispersion of CNTs and polymer electrolyte, the composite cathode is covered by film-like discharge products Li2CO3. Furthermore, the Li–CO2 battery shows high reversible capacity (~ 11,000 mAh·g−1), excellent cycle stability (1000 mAh·g−1 for 100 cycles) under low charge potential (