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Intrinsically disordered proteins (IDPs) participate in various biological processes. Interactions involving IDPs are usually dynamic and are affected by their inherent conformation fluctuations. Comprehensive characterization of these interactions based on current techniques is challenging. Here, we present GSALIDP, a GraphSAGE-embedded LSTM network, to capture the dynamic nature of IDP-involved interactions and predict their behaviors. This framework models multiple conformations of IDP as a dynamic graph, which can effectively describe the fluctuation of its flexible conformation. The dynamic interaction between IDPs is studied, and the data sets of IDP conformations and their interactions are obtained through atomistic molecular dynamic (MD) simulations. Residues of IDP are encoded through a series of features including their frustration. GSALIDP can effectively predict the interaction sites of IDP and the contact residue pairs between IDPs. Its performance in predicting IDP interactions is on par with or even better than the conventional models in predicting the interaction of structural proteins. To the best of our knowledge, this is the first model to extend the protein interaction prediction to IDP-involved interactions.

The Na3V2(PO4)2O2F (NVPOF) is synthesized with high conversion rates and uniform morphology, by rapid precipitation of adjusting the pH and temperature. And the effect of reaction temperature on the performance is mainly investigated, and the results show that the rise of reaction temperature is beneficial to the increase of F content and conversion rate. Furthermore, micro morphology can be designed by adjusting temperature and other conditions. Then the NVPOF/C with modification of robust carbon coating is conducted, and the surface structure has been characterized. The optimized NVPOF/C based hybrid exhibits a specific capacity of 116.7 mAh·g−1at 0.1C and it has long cycle performance (92.0 % retention rate after 200 cycles at 1C) and high capacity at high current density (78 mAh·g−1at 10C). Consequently, a simple and controllable precipitation method is provided to prepare micro-nano NVPOF/C with high rate performance and indicate the importance of morphology and surface stability control.

Conventional polycrystalline LiMn2O4(PC-LMO) suffers from poor Li+diffusion rates and structural instability, negatively affecting its electrochemical performance. Here, we design a single-crystal LMO cathode material using BaO flux (SC-LMOB) to address these issues. The BaO flux enables the fabrication of brick-like single-crystal particles, enhancing Li+diffusion by shortening the diffusion path and increasing the unit cell volume. This process also reduces the specific surface area and stabilizes the crystal structure, effectively mitigating Mn dissolution and polarization. As a result, SC-LMOB exhibits ultra-high rate performance and superior structural stability, retaining 88.8% of its capacity at a 20 C discharge rate and achieving capacity retentions of 85.3% and 86.0% after 500 and 300 cycles at 1 C at room and elevated temperatures, respectively. This structural design offers a low-cost, scalable approach for fabricating single-crystal cathode materials with excellent performance.

The solid-state reaction has been widely employed as the standard procedure to prepare oxide cathode materials for sodium-ion batteries. However, it involves multiple steps and consumes much energy. In this work, we report a facile method to synthesize a large-grained O3–NaCrO2cathode by directly reducing sodium dichromate dihydrate (Na2Cr2O7·2H2O) under a hydrogen atmosphere. Owing to its unique large particle morphology, the as-prepared NaCrO2exhibits a high tap density of 2.55 g cm–3. The compact NaCrO2shows excellent electrochemical performance with a high reversible capacity of 123 mAh g–1at 0.1C, a high capacity retention of 88.2% after 500 cycles at 2C, and an outstanding rate capability of 68 mAh g–1at 20C. The performance is attributed to a stable structure from the distinctive morphology with small specific surface area to suppress interfacial side reactions and rapid Na-ion diffusion channels with a highly (110)-oriented crystal structure. Ex situ X-ray diffraction and cyclic voltammetry tests demonstrate the consecutive and reversible phase transition mechanism with facile Na+migration. Importantly, the obtained cathode material exhibits an excellent performance in sodium-ion full cells with hard carbon as the anode.

The influence of sintering temperature, carbon content and dispersive agent in ball-milling was investigated on the properties of LiFePO4/C prepared using Fe2O3, NH4H2PO4, Li2CO3and glucose viasolid state reaction. X-ray powder diffraction, scanning electron microscopy and charge–discharge test were applied to the characterization of the LiFePO4/C samples synthesized under different conditions. Sintering temperature affects the crystallite/particle size and degree of crystallinity of LiFePO4, formation of Fe2P and maintenance of carbon in LiFePO4/C. Carbon maintenance is favored by low sintering temperature, and 700°C is optimum for synthesis of LiFePO4/C with superior electrochemical performance. A higher carbon content in the range of 4.48%–11.03% results in a better rate capability for LiFePO4/C. The dispersive agent used in ball-milling impacts the existent state of carbon in the final product which subsequently determines its charge–discharge behavior. The sample prepared at 700°C by using acetone as the dispersive agent in ball-milling exhibits an excellent rate capability and capacity retention without any fade at 0.1C, 1Cand 2C, with corresponding average discharge capacities of 153.8, 128.3 and 121.0mA·h·g−1, respectively, in the first 50cycles.

Graphene has been implemented as a desirable additive to improve the electrochemical performance of Ni-rich cathode materials. However, it is not only hard to ensure the intimate interaction between them in practice, which may affect the surface electronic conductivity of the composite, but also a challenge to fabricate cathodes with uniform graphene coating because of its two-dimensional planar structure. Besides, the graphene coating layer is easily peeled off from the cathode material during the cycling process, especially at the upper cutoff voltage. Therefore, we introduced a double-functional layer synergistically modified strategy to facilitate the electrochemical properties of LiNi0.8Co0.1Mn0.1O2cathode materials. In the designed architecture, the LiNi0.8Co0.1Mn0.1O2particles were uniformly enwrapped by a functional reduced graphene oxide (RGO)–KH560 polymer composite layer which consists of an inner high-flexibility epoxy-functionalized silane (KH560) layer and an outer RGO layer with high electronic conductivity. The KH560 layer, in the structural system, is especially critical in connecting the layer of outer RGO and the inner surface of the active material, which brings about the perfect and complete double-functional coating layer and in turn fully expresses the modification effect of both KH560 and RGO in the improvement of electrochemical performance. Consequently, higher capacity retention, better rate, and improved high-temperature performances (55 °C) at the upper cutoff voltage (4.5 V) of this composite are identified when compared with the RGO-coated and pristine samples. In particular, the cathode with RGO (0.5%)–KH560 (0.5%) coating exhibits capacity retentions of 95.2 and 81.5% after 150 cycles at 1 C, 4.5 V at room and high temperatures, respectively.

The Co-less Ni-rich (Ni ≥ 90 %) layered cathode materials are attracting attention because of their high specific capacity and relatively low cost. However, its application is hampered by low cycling stability and structural susceptibility to deterioration. To resolve these issues, the Li0.994Mg0.006(Ni0.925Co0.03Mn0.045)0.996Zr0.004O2(MZ-NCM) cathode material co-doped with magnesium and zirconium ions was synthesized by the solid-phase method through optimization of the formulation. The physicochemical properties of the materials were investigated in detail by XRD, SEM, EDS, XPS and HR-TEM. Compared with the bare NCM, the MZ-NCM exhibits excellent electrochemical performance with capacity retention of 82.03 % after 150 cycles and discharge specific capacity of 171.81 mAh g−1at rate of 10C. Comparison of dQ/dV, XRD, SEM and HR-TEM of the electrodes after cycling indicated that the Mg2+and Zr4+co-doped cathode maintains intact spherical morphology and relatively stable layered structure.

Overlithiated oxide cathode materials show high capacity but poor cycle stability and voltage attenuation. In this work, a concentration difference driven molten salt ion exchange strategy is used to replace a small quantity of lithium ions by sodium ions. With the entry of sodium ions, the interplanar spacing is increased and the structure is stabilized. The electrochemical properties of materials have been improved obviously. The powder X-ray diffraction, inductively coupled plasma atomic emission spectroscopy, scanning electron microscopy, and transmission electron microscopy are used to detect the entry of sodium ions and structural changes. The modified materials display high discharge specific capacity, excellent cycling performance, and reduced voltage attenuation.

Ni-rich cathode materials have drawn lots of attention owing to its high discharge specific capacity and low cost. Nevertheless, there are still some inherent problems that desiderate to be settled, such as cycling stability and rate properties as well as thermal stability. In this article, the conductive polymers that integrate the excellent electronic conductivity of polyaniline (PANI) and the high ionic conductivity of poly(ethylene glycol) (PEG) are designed for the surface modification of LiNi0.8Co0.1Mn0.1O2cathode materials. Besides, the PANI–PEG polymers with elasticity and flexibility play a significant role in alleviating the volume contraction or expansion of the host materials during cycling. A diversity of characterization methods including scanning electron microscopy, energy-dispersive X-ray spectrometer, transmission electron microscopy, thermogravimetric analysis, Fourier transform infrared have demonstrated that LiNi0.8Co0.1Mn0.1O2cathode materials is covered with a homogeneous and thorough PANI–PEG polymers. As a result, the surface-modified LiNi0.8Co0.1Mn0.1O2delivers high discharge specific capacity, excellent rate properties, and outstanding cycling performance.

Let $(X,d,\unicode[STIX]{x1D707})$be a metric measure space endowed with a distance $d$and a nonnegative, Borel, doubling measure $\unicode[STIX]{x1D707}$. Let $L$be a nonnegative self-adjoint operator on $L^{2}(X)$. Assume that the (heat) kernel associated to the semigroup $e^{-tL}$satisfies a Gaussian upper bound. In this paper, we prove that for any $p\in (0,\infty )$and $w\in A_{\infty }$, the weighted Hardy space $H_{L,S,w}^{p}(X)$associated with $L$in terms of the Lusin (area) function and the weighted Hardy space $H_{L,G,w}^{p}(X)$associated with $L$in terms of the Littlewood–Paley function coincide and their norms are equivalent. This improves a recent result of Duong et al.[‘A Littlewood–Paley type decomposition and weighted Hardy spaces associated with operators’, J. Geom. Anal.26(2016), 1617–1646], who proved that $H_{L,S,w}^{p}(X)=H_{L,G,w}^{p}(X)$for $p\in (0,1]$and $w\in A_{\infty }$by imposing an extra assumption of a Moser-type boundedness condition on $L$. Our result is new even in the unweighted setting, that is, when $w\equiv 1$.

A facile solution route was employed for the preparation of an Al doped ZnO (AZO) coating layer, which was composed of many AZO nanoparticles. These nanoparticles have an average particle size of 50 nm and have been successfully decorated on the surface of NCM523. As cathode material for lithium ion batteries, the AZO-decorated NCM523 exhibits superior lithium storage improvements according to good cyclic performance, enhanced rate performance (134.2 mAhg–1after 200 cycles at 10 C), and high-temperature performance (148.9 mAhg–1at 10 C at 60 °C). Such significant improvement could be attributed to the structural superiority of the AZO decoration on the surface of NCM523, which would stabilize the surface structure of the bulk, suppress the undesirable side reaction at the interface of the electrodes, and lead to the enhancement of the conductivity. The preparation of AZO-decorated NCM523 provides an effective method for the high-performance lithium ion batteries and has a certain reference for other materials.

Recently, cathode materials for Li-ion batteries (LIBs) with high-voltage platforms have become a research hotspot. Olivine-structured LiMnPO4has the advantage of 4.1 V voltage platform but also has been plagued by poor e-/Li+ conductivity. Here, we report a facile synthetic strategy to fabricate LiMn0.6Fe0.4PO4/C (LMFP) composite. Such composite is composed of [001]-oriented nanorods and assembled into dense microspheres. The [001]-oriented nanorod structure exhibits a shortened Li+diffusion length resulting from a smaller dimensional size in the [010] direction. Meanwhile, the conductive carbon nanolayer is uniformly coated on the surface of LiMn0.6Fe0.4PO4nanorods, which greatly improves the e-conductivity of the material. The [001]-oriented structure feature combined with improved e-conductivity contributes to the delivery of extraordinary rate capabilities (141.6 mAh/g at 10C) and remarkable cycling stabilities (97.8% retention rate after 300 cycles at 1C). Such rational-designed nanorod microspheres are good candidates for the next generation of olivine-structured cathode for high-rate, high-energy, and high-safety LIBs.

The electrochemical performance of Ni-rich cathode material at high temperature (>50 °C) and upper voltage operation (>4.3 V) is a challenge for next-generation lithium-ion batteries (LIBs) because of the rapid capacity degradation over cycling. Here we report improved performance of LiNi0.8Co0.15Al0.05O2materials via a LiAlO2coating, which was prepared from a Ni0.80Co0.15Al0.05(OH)2precursor by spray-drying coating with nano-Al2O3. Investigations by X-ray diffraction, scanning electron microscopy, energy-dispersive X-ray spectroscopy, and transmission electron microscopy revealed that an Al2O3layer is uniformly distributed on the precursor and a LiAlO2layer on the as-prepared cathode material. Such a coating shell acts as a scavenger to protect the cathode material from attack by HF and serious side reactions, which remarkably enhances the cycle performance at 55 °C and upper operating voltage (4.4 and 4.5 V). In particular, the sample with a 2% Al2O3coating shows capacity retentions of 90.40%, 85.14%, 87.85%, and 81.1% after 150 cycles at a rate of 1.0C at room temperature, 55 °C, 4.4 V, and 4.5 V, respectively, which are significantly higher than those of the pristine one. This is mainly due to the significant improvement of the structural stability led by the effective coating technique, which could be extended to other cathode materials to obtain LIBs with enhanced safety and excellent cycling stability.

Sodium is first introduced to modify Ni-rich LiNi0.8Co0.15Al0.05O2cathode material in this work, and Li1–xNaxNi0.8Co0.15Al0.05O2(x= 0, 0.01, 0.02, 0.05) is successfully synthesized by using Na2CO3as sodium resource through coprecipitation and solid state calcination route. The morphology of the samples analyzed with SEM, EDS. and TEM show that all the samples maintain sphere-like morphology and the main elements are uniformly distributed. X-ray diffraction (XRD) results show that all the synthesized materials have typical hexagonal structure without impurities. The lattice parameters calculated from the XRD data are also refined by Rietveld refinement methods, confirming that the position of Na in the NCA is occupying the Li slab as designed. Despite a slight decrease in the initial discharge capacities, the sodium doped materials display improved capacity retention as well as superior performance at high rates. The Li0.99Na0.01Ni0.8Co0.15Al0.05O2exhibits an initial discharge specific capacity of 184.6 mAh g–1at 0.1 C and a capacity retention of 90.71% after 200 cycles when cycled at 1 C between 2.8 and 4.3 V, which is greatly superior to the pristine one, owing to the enlarged Li layer spacing, decreased Li+migration activation energy, the low cation mixing, and enhanced structural stability brought by sodium treatment.

A facile and practical route was introduced to prepare LiFePO4/C cathode material with nano-sized primary particles and excellent electrochemical performance. LiH2PO4was synthesized by using H3PO4and LiOH as raw materials. Then, as-prepared LiH2PO4, reduced iron powder and a-D-glucose were ball-milled, dried and sintered to prepare LiFePO4/C. X-ray diffractometry was used to characterize LiH2PO4, ball-milled product and LiFePO4/C. Differential scanning calorimeter-thermo gravimetric analysis was applied to investigate possible reactions in sintering and find suitable temperature for LiFePO4formation. Scanning electron microscopy was employed for the morphology of LiFePO4/C. As-prepared LiH2PO4is characterized to be in P21cn(33) space group, which reacts with reduced iron powder to form Li3PO4, Fe3(PO4)2and H2in ball-milling and sintering. The appropriate temperature for LiFePO4/C synthesis is 541.3-976.7 °C. LiFePO4/C prepared at 700 °C presents nano-sized primary particles forming aggregates. Charge-discharge examination indicates that as-prepared LiFePO4/C displays appreciable discharge capacities of 145 and 131 mA·h·g−1at 0.1 and 1 C respectively and excellent discharge capacity retention.

Abstract: Dempster and Rubin (D&R) in their JRSSB paper considered the statistical error caused by data rounding in a linear regression model and compared the Sheppard correction, BRB correction and the ordinary LSE by simulations. Some asymptotic results when the rounding scale tends to 0 were also presented. In a previous research, we found that the ordinary sample variance of rounded data from normal populations is always inconsistent while the sample mean of rounded data is consistent if and only if the true mean is a multiple of the half rounding scale. In the light of these results, in this paper we further investigate the rounding errors in linear regressions. We notice that these results form the basic reasons that the Sheppard corrections perform better than other methods in DR examples and their conclusion in general cases is incorrect. Examples in which the Sheppard correction works worse than the BRB correction are also given. Furthermore, we propose a new approach to estimate the parameters, called “two-stage estimator”, and establish the consistency and asymptotic normality of the new estimators.

Recent experiments suggested that adenosine triphosphate (ATP) can regulate liquid–liquid phase separation (LLPS) of various proteins and inhibit protein aggregations at its physiological concentration, which is highly correlated with the nonspecific interactions of ATP to a wide variety of proteins. However, the mechanism underlying the general binding capability of ATP largely remains unclear. In this work, we used molecular dynamics simulation to study the binding of ATPs to three proteins with distinct net charges: TDP-43 NTD (−7 e), TAF15-RRM (0 e), HWEL (+8 e). Negatively charged ATP exhibits a strong trend to accumulate around all of these proteins. While only a fraction of the accumulated ATPs directly binds to the limited regions of the protein surface, additional ATPs indirectly bind to proteins by aggregating into ATP clusters. Hence, the proportion of the directly bound ATPs in the clusters as well as their binding regions can be adjusted in response to different proteins, which makes ATP well adapted to a variety of proteins. Moreover, our results suggest that ATP tightly binds to Arg with high affinity, and Arg dominates the direct binding of ATP. Meanwhile, Arg also affects the self-association of accumulated ATPs. The size of the ATP cluster is effectively regulated by the distribution of Arg. Considering the ubiquity of Arg in proteins, our findings are helpful to understand the general binding capability of ATP.

Abstract.: Conventional RTK positioning is usable, but requires the use of a local base station. It is also restricted by the effects of the de-correlate atmospheric refraction on the GPS signal, which limits the use of the RTK positioning up to distances of 10–15 km from the reference station to the user. With a multiple reference station network approach, precise RTK positioning capability may be extended for a much larger area. The Singapore Integrated Multiple Reference Station Network (SIMRSN) has been established for this purpose. Using an existing method termed linear combination method, the multiple reference station network corrections are generated for the user on an epoch by epoch, satellite-by-satellite basis. A residual-based adaptive Kalman filter is proposed to improve network correction availability. The VRS concept is used to transmit corrections to the user for RTK positioning. Field tests were conducted to demonstrate the general performance of SIMRSN. The tests confirmed that RTK positioning within a multiple reference station network can provide the user with better than 3 cm in horizontal position, the height accuracy is in the range of 1–7 cm, and the average TTF (Time To Fix) are 46 and 76 s during GLC station and LPR station tests, respectively. With this highly efficient survey technique, the user needs only to be equipped with a single GPS receiver. This reduces equipment and manpower costs compared with traditional RTK positioning using a specially set up reference station. The multiple reference station framework also paves the way for various other applications beyond the traditional surveying profession.

A mixed lithium-sodium layered manganese oxide, i.e. Na0.6[Li0.2Mn0.8]O2, with a P2 structure, is synthesized using a simple solid-state method. An initial discharge capacity of 247 mAh g[?]1 is achieved for Na0.6[Li0.2Mn0.8]O2/Li cells cycled between 2.0 and 4.8 V at 0.1 C. The average voltage is 3.52 V, which corresponds to an energy density of 878.2 Wh kg[?]1; this is almost 50% higher than that of LiCoO2. During the following cycles, the material undergoes Na/Li exchange and structural changes. Although a new phase similar to Li2MnO3 forms after cycling, the material displays a stable capacity greater than 240 mAh g[?]1 over 30 cycles.

Disk-like micron-sized monocrystalline LiNi0.5Co0.2Mn0.3O2is synthesized by the co-precipitation method accompanied with calcination assisted by strontian carbonate without washing process or other complicated treatment. Powder X-ray diffraction, scanning electron microscopy, and transmission electron microscopy are used to characterize the obtained samples. Characterizations reveal that the addition of SrCO3help to form monocrystalline LiNi0.5Co0.2Mn0.3O2with preferred (104) plane, and the particle is disk-like and in micrometer size. Electrochemical test results indicate that the LiNi0.5Co0.2Mn0.3O2exhibits significantly improved capacity retentions of 95.6% and 89.3% after 100 cycles at 1C, for the voltage ranges of 2.8?4.3 V and 2.8?4.5 V, respectively. The excellent cycle performance of the LiNi0.5Co0.2Mn0.3O2is ascribed to the unique monocrystalline morphology, high stability of (104) plane and reduced irreversible phase transition.

Ni-rich layered oxides are extensively employed as a promising cathode material in lithium ion batteries (LIBs) due to their high energy density and reasonable cost. However, the hierarchical structure of secondary particles with grain boundaries inevitably induces the structural collapse and severe electrode/electrolyte interface parasitic reactions as the intergranular crack arises from the anisotropic shrink and expansion. Herein, the single-crystalline LiNi0.83Co0.11Mn0.06O2(SC-NCM) with primary particles of 3–6 μm diameter is developed and comprehensively investigated, which exhibits superior cycling performance at both room temperature and elevated temperature (55 °C) as well as significantly improved structural integrity after long-term cycling. Remarkably, the SiO-C||SC-NCM pouch-type full cell with a practical loading (8.7 mAh cm−2) delivers a capacity retention of 84.8 % at 45 °C after 600 cycles at a current rate of 1C (1C = 200 mA g−1), retaining a high specific energy density of 225 Wh/kg. Using a combination of X-ray photoelectron spectroscopy, time-of-flight secondary-ion mass spectrometry and scanning transmission electron microscopy, we reveal that SC-NCM particles with micron-sizes effectively mitigate the undesired electrode/electrolyte side interactions and prevent the generation of intergranular cracks, thereby alleviating irreversible structural degradation. The strategy of developing single-crystalline micron-sized particles may offer a new path for maintaining the structural stability and improving cycling life of Ni-rich layered NCM cathodes even under high temperature.

This study investigated the application of a therapeutic tumor cell–derived microparticle-based nanodelivery platform in malignant pleural effusion.

A mixed lithium-sodium layered manganese oxide, i.e. Na0.6[Li0.2Mn0.8]O2, with a P2 structure, is synthesized using a simple solid-state method. An initial discharge capacity of 247 mAh g−1is achieved for Na0.6[Li0.2Mn0.8]O2/Li cells cycled between 2.0 and 4.8 V at 0.1 C. The average voltage is 3.52 V, which corresponds to an energy density of 878.2 Wh kg−1; this is almost 50% higher than that of LiCoO2. During the following cycles, the material undergoes Na/Li exchange and structural changes. Although a new phase similar to Li2MnO3forms after cycling, the material displays a stable capacity greater than 240 mAh g−1over 30 cycles.

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