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Poor electrical connections contribute to electrical fires. The ignition process due to poor electrical contacts was studied and revealed the triggering mechanisms at crucial stages. By manipulating the contact resistance to simulate real-world poor connection scenarios, three distinct stages were identified in the ignition process. Stage I, referred to as temperature rise and pyrolysis, is attributed to high resistance at electrical contacts. Stage II, referred to as arc-accelerated pyrolysis, is the complete formation of a carbonized path due to insulation breakdown, and Stage III, referred to as ignition and combustion, is the ignition of pyrolysis gases by the arc on the carbonized path. The duration of Stages I and II is strongly correlated with the electrical contact power (Q̇cR) and the arc power (Q̅arc). The transition from Stage I to Stage II occurs at a critical electrical contact power of 35 W. Two critical thresholds exist for the transition from Stage II to Stage III: an ignition threshold Q̅arc1(about 50 W), and an extremely easy ignition threshold Q̅arc2(about 250 W), both determined by the initial fire core control volume energy formed by pyrolysis gases and the arc, and by the surrounding environment. Fault development pathways in electrical connectors and key parameter changes were identified, providing support for enhancing electrical safety inspections and risk prevention strategies.

In this paper, we study Miyaoka-type inequalities on Chern classes of terminal projective 3-folds with nef anti-canonical divisors. Let Xbe a terminal projective 3-fold such that −KXis nef. We show that if c1(X) · c2(X) ≠ 0, then c1(X)⋅c2(X)⩾1252; if further Xis not rationally connected, then c1(X)⋅c2(X)⩾45and this inequality is sharp. In order to prove this, we give a partial classification of such varieties along with many examples. We also study the nonvanishing of c1(X)dim X− 2·c2(X) for terminal weak Fano varieties and prove a Miyaoka-Kawamata-type inequality.

Herein, we report a strategically novel method for the efficient construction of indole skeletons using 2-phenylisoxazol-5-ones as the starting material. This reaction proceeds via Brønsted acid-promoted α-iminyl cation generation by N–O bond cleavage and a subsequent intramolecular cyclization to afford 1H-indole-3-carboxylic acid, which further undergoes decarboxylation to yield the final product. Control experiments show that N–O bond cleavage and intramolecular cyclization proceed so fast that the 1H-indole-3-carboxylic acid could be isolated in high yields even after 5–10 min. The substrate scope of this transformation is broad, and the desired products are obtained in moderate to good yields. The transition-metal-free reaction condition, CO2as the sole byproduct, and good practicability add to the synthetic potential of this transformation in the pharmaceutical and flavor industries.

An efficient visible‐light‐induced iminothiolation of unactivated alkenes has been developed for the rapid construction of pyrroline derivatives bearing a thioether moiety. In the presence of fac‐Ir(ppy)3as photoredox catalyst, the acyl oximes were readily converted into iminyl radicals by single electron reduction under white LEDs irradiation, and the following radical cascading intramolecular cyclization and thioetherification would afford the functionalized pyrrolines with high efficiency. The mild reaction conditions including air atmosphere and ambient temperature allow for broad functional group tolerance. In addition, the good compatibility and practicality of this protocol is further highlighted by the employment of easily available thiophenols as the sulfur source for the thiolation process. Taking advantage of easily available thiophenols as sulfur source, a visible‐light‐promoted iminothiolation of unactivated alkenes was developed for the synthesis of pyrroline derivatives.

Controlling the morphology of highly homogeneous nanoribbons is one of the main goals for synthesizing catalysts with excellent activity and durability. In this Communication, platinum (Pt) nanoribbons were synthesized by a one-pot method. We used ammonium fluoride (NH4F) as the regulator, under 8 atm of hydrogen (H2), to synthesize zigzag-shaped two-dimensional Pt nanoribbons. Benefiting from their unique morphology, the Pt nanoribbons display superior electrocatalytic activity and stability.

This study was aimed to investigate the cryoprotective effects of silver carp muscle hydrolysate (SCMH, 14% degree of hydrolysis) on frozen dough subjected to 0–6 freeze–thaw cycles, using trehalose as a reference. The results showed that the addition of SCMH in dough led to significant increase (p< 0.05) of the survival rates (79–93%) and relative fermentation capacity (59–95%) of yeast in dough subjected to 2–6 freeze–thaw cycles as compared to the control (survival rates: 43–59%; relative fermentation capacity: 29–58%) and trehalose (survival rates: 61–71%; relative fermentation capacity: 48–73%) treated counterparts. The presence of SCMH in dough also led to an increase in the specific volume of the resulting bread as well as decreases in the hardness, adhesiveness, and chewiness of bread, indicating that SCMH has a good cryoprotective effect on frozen dough. Further analysis found that the freezable water content of frozen dough with SCMH increased by only 5% after 6 freeze–thaw cycles, significantly less (p< 0.05) than the control (increased by 11%) and trehalose treated dough (increased by 9%). Accordingly, frozen dough that included SCMH showed less starch granule deformation and a more complete gluten structure, while the resulting bread was characterized by larger gas-cell density and smaller average cell area. These findings could be interpreted as the consequences of reduced formation and recrystallization of ice crystals due to decreased freezable water content, as well as the subsequent reduction in freeze-damage to the frozen dough.

Chemical modification of cellulose is beneficial to produce highly porous lithium-ion battery (LIB) separators, but introduction of high charge density adversely affects its electrochemical stability in a LiNi1/3Mn1/3Co1/3O2(NMC)/graphite full cell. In this study, the influence of carboxylate functional groups in 2,2,6,6-tetramethylpiperidine-1-oxyl-mediated oxidized cellulose nanofibers (TOCNs) on the electrochemical performances of the LIB separator was investigated. X-ray photoelectron spectroscopy and in operando mass spectrometry measurements were used to elucidate the cause of failure of the batteries containing TOCN separators in the presence and absence of sodium counterions in the carboxylate groups and additives. For the TOCN separator with sodium carboxylate functional groups, it seems that Na deposition is the dominant reason for poor electrochemical stability of the cell thereof. The poor performance of the protonated TOCN separator, attributed to a high amount of gas evolution, is dramatically improved by adding 2 wt % of vinylene carbonate (VC) because of suppressed gas evolution. Unveiling the failure mechanism of the TOCN separators and successively implementing the strategies to improve performance, for example, removing Na, adding VC, and adjusting cycling rates, enable a remarkable cycling performance in the NMC/graphite full cell at ≈2 C (3 mA/cm2) of a fast discharging rate. Despite the aforementioned efforts and compromises required, an increased charge density of the TOCN is beneficial to acquire a mechanically stronger separator. In conclusion, the manufacturing process of cellulose nanofibers needs to be carefully adjusted to acquire a desired separator property. To the best of our knowledge, it is first reported to perform operando gas evolution measurements to systematically investigate the electrochemical stability of nanocellulose as an LIB separator material. The results elucidate not only the challenges for extensive applications of hygroscopic biomaterials for commercial LIBs but also the practical solutions to achieve high electrochemical stability of the materials.

Silk fibroin-based conducting hydrogels possess hierarchical structural motifs featuring unique properties, but the development of such materials has proven to be challenging. Herein, we develop a novel strategy for the fabrication of a conducting silk fibroin hydrogel based on an interpenetrated network of poly(3,4-ethylene dioxythiophene):poly(styrene sulfonate) (PEDOT:PSS) and silk fibroin. The hydrogel possesses good electrical conductivity and considerable capacitance and cycling stability due to the existence of the PEDOT conducting network, as well as enhanced mechanical properties such as compressibility due to β-sheets in the silk fibroin network and Ca2+cross-linking of the PSS components. A symmetric charge storage device based on conductive silk fibroin hydrogel electrodes exhibited a remarkable areal capacitance of 1.1 F cm–2at 0.5 mA cm–2, as well as a good capacitive response under a compressed state. This combination of compression strength and electrochemical properties makes this conducting silk hydrogel a potential material for unconventional energy storage applications.

In this research, we investigate and understand the training injuries of basketball players, analyse the factors that cause training injuries, and use polyethylene wood plastic composite single-lap glued joints as the research object. Through different surface treatment methods, bonding processes, and a glueing study on agent performance, bonding strength, stress distribution, and durable failure behaviour of bonding, design single-lap bonding joints, and finally realise seamless connection and bonding joint design of polyethylene wood plastic composites by bonding technology. The rationality of the injury prevention training system was established and applied in basketball, which verified the effectiveness and scientific accuracy of the injury prevention training system. The purpose of this paper is to construct and verify a basketball player training injury system. Based on the existing training system, on the floor made of polyethylene wood plastic composite materials, through practice to effectively design a training program to prevent sports injuries and reduce the incidence of injuries. Lowered to a controllable range, it proves that nano-flexible solid wood composite environmentally friendly flooring can be applied to basketball, which can extend the athlete's sports career to the greatest extent and is committed to improving the athlete's ultimate sports performance.

A strategically novel protocol for ring-opening functionalization of aryl gem-difluorocyclopropanes (F2CPs), which allows an expedient construction of CF3-containing architectures via visible-light-promoted F-nucleophilic attack manifold, was disclosed. Single electron oxidation of F2CPs was ascribed as the critical step for the success of this transformation by prompting F-nucleophilic attack, as well as the ensuing C–C bond scission. The observed intriguing regioselectivity for fluoroincorporation in this reaction was rationalized by invoking the cation-stabilization property of gem-difluorine substituents and also the thermodynamic gains acquired from forming CF3functionality. By using cost-effective fluorination reagent and readily available substrates, a broad collection of structurally diversified α-allyl-β-trifluoromethyl ethylbenzene derivatives could be obtained in generally good yields. Further mechanistic investigations proved the engagement of a benzylic radical intermediate in this transformation.

The practice of conservation tillage or straw returning to the farmland influences the grain yield and quality of rice (Oryza sativa). The key volatile compound responsible for the fragrance in fragrant rice is 2-acetyl-1-pyrroline (2-AP), which is significantly affected by field management measures. The purpose of this study was to investigate the impact of tillage management and straw returning on the grain yield and biosynthesis of 2-AP in fragrant rice. This study was conducted over two years in 2016 and 2017 and utilized two fragrant rice cultivars (Meixiangzhan 2 and Xiangyaxiangzhan) as materials. It consisted of different tillage managements and straw returning treatments, which included three tillage managements: rotary tillage (T0), minimum tillage (T1), and no tillage (T2), and two straw returning treatments: without straw returning (S0) and straw returning (S1). The straw used for the experiment was sourced from the residue of the early season harvested corresponding fragrant rice cultivar. Tillage management and straw returning substantially affected the grain yield, grain quality, and 2-AP content of both fragrant rice cultivars. Compared with the T0S0 treatment, tillage management and straw returning resulted in an improvement in the 2-AP content in 2016 (12.41-116.85%) and 2017 (34.85-103.89%) on average. A higher content of 2-AP was detected in both fragrant rice cultivars in the T2S1 and T1S1 treatments. A structural equation model (SEM) demonstrated that the enzyme activities of fragrance metabolism in the leaves and grain jointly regulated the biosynthesis of precursors of fragrance metabolism in the grain, which further promoted the accumulation of 2-AP. In addition, a principal component analysis indicated that the T1S1 treatment positively correlated with both 2-AP and grain yield. The SEM demonstrated that the enzymes related to nitrogen metabolism, parameters related to photosynthesis, and yield component contributed to the grain yield. The T1S1 treatment resulted in the highest average grain yield of 760.75 g m-2, which can be attributed to an increase in various attributes, such as the leaf area index, SPAD value, nitrogen metabolism, panicle number per m2, and grain number per panicle. The minimum tillage and straw returning (T1S1) treatment is more effective at simultaneously improving both the grain yield and 2-AP content in fragrant rice.

This review introduces soft electronics for health monitoring assisted by machine learning, and discusses soft materials, physiological signals, and machine learning algorithms in sequence and their relationships.The principles of classic machine learning algorithms and neural network algorithms are summarized and explained by representative examples combining with soft electronics.The potential challenges of soft electronics assisted by machine learning especially in health monitoring field are outlined, and future research directions are outlooked.

Background: In AFM study of cell mechanical properties, the apparent elastic modulus of a cell is affected by many factors, especially the AFM tip geometry, indentation site of the cell, the application of the mathematical model and testing conditions. Methods: In this study, indentation experiments of living cells under different conditions were performed aiming to build an accurate evaluation system of mechanical properties of lung cancer cells based on AFM. Comparisons of the effects of spherical and pyramid AFM tips, Hertz model of semiinfinite and finite thickness, cell nuclear and cytoplasmic indentation regions on the cell apparent elastic modulus were accomplished. Results: Compared with the calculated results by spherical tip, the elastic modulus distribution of non-small lung cancer cells (NSCLC) by pyramid tip was observed to be similar while the absolute values increased obviously, which were more than twice the numerical values by the spherical tip (p<0.05). The apparent elastic modulus values were the overvalued cause of the underestimation of the contact region in pyramidal tip measurement. Two different indentations over nucleus or lamellipodium of NCI-H520 cell and NCI-H1299 cell were analyzed. Consequently, the exact elastic modulus over the nucleus area can be calculated accurately using the semi-infinite Hertz model while the finite thickness Hertz model should be used for elasticity assessment of cell lamellipodium with a small thickness. Conclusion: This evaluation system provides technological support for accurate evaluation of viscoelastic properties of living cancer cells.

Objectives This study aimed to examine a simple, effective, time-saving, and low-cost protein microarray method for detecting serum alpha-fetoprotein (AFP) and AFP-L3 levels.Methods Serum samples from patients with hepatocellular carcinoma (HCC) (n = 33) and control subjects (n = 39) were collected and evaluated for the presence of AFP using a novel protein microarray. Glycoprotein (including AFP-L3) was enriched from crude samples by a Hotgen Biotech glycosyl capture spin column and then detected by protein microarray. An electrochemiluminescence immunoassay (ECLIA) was used to validate the measured values.Results Neither AFP levels lower than 20 ng/mL in the HCC group nor AFP levels higher than 20 ng/mL in the control group were found when tested by the ECLIA and protein microarray. The kappa test showed good consistency in the diagnostic performance of measuring serum AFP levels and the percentage of AFP-L3 in total AFP by the ECLIA and protein microarray. Protein microarray had advantages of smaller sample size required, low cost, and convenience compared with the ECLIA.Conclusion The protein microarray assay that was developed in the present study shows potential as an economic and convenient technique for detecting AFP and AFP-L3 levels in serum samples from patients with HCC.

Herein, we report the first example of group transfer radical addition of O-vinylhydroxylamine derivatives onto unactivated alkenes. By utilizing O-vinylhydroxylamine derivatives as both the N- and C-donors, this reaction enables intermolecular carboamination of unactivated alkenes in an atom economical fashion. As the process is initiated through N-radical addition followed by C-transfer, linear carboamination products are afforded. This differs from canonical radical carbofunctionalization of olefins, which typically favors branched product owing to initiation by C-radical addition.

Micron-sized truncated octahedral LiNi0.5Mn1.5O4 (LNMO) samples with different degrees of Ni/Mn disordering have been obtained by controlling the synthesis conditions, such as calcination atmosphere (O2 and air), cooling rate or additional annealing step. The influences of Ni/Mn disordering on the physical properties and electrochemical performance of the truncated octahedral LNMO samples have been systematically investigated. The analyses of thermogravimetry, X-ray photoelectron spectroscopy, X-ray diffraction, powder neutron diffraction, Raman spectroscopy and X-ray absorption spectroscopy reveal that the occurrence and degree of Ni/Mn disordering are closely related with the formation of oxygen vacancies and presence of Mn3+. Slow cooling rate and post-annealing can result in low degrees of Ni/Mn disordering and oxygen vacancies. Electrochemical measurements show that Ni/Mn disordering and oxygen vacancies have no obvious effect on the rate capability since all LNMO samples share a truncated octahedral morphology with the exposed {100} surfaces. However, they play significant roles in improving long-term cycling stability, especially at the elevated temperature of 60degC. This work suggests that the electrochemical performance of LNMO with optimized truncated morphology can be further enhanced through tuning the degrees of Ni/Mn disordering and oxygen vacancies.

Surface topography of cancer cell is particularly vital since cell frequently changes its shape as interacting with neighbouring cells and extracellular matrix. Atomic force microscope (AFM) has an extraordinary superiority in surface scanning of cells but the scanning consequence depends upon experiment conditions or experience primarily. In our study, a quadratic regression orthogonal rotation combination design was operated to acquire optimal parameters for cell profiling via AFM. By iterative calculation, the optimum AFM scanning of cell can be accomplished at setpoint of 0.61 V, scanning rate of 2.23 Hz and proportional gain of 3.85. Satisfactory surface morphology images of human bronchial epithelium BEAS-2B and pulmonary adenocarcinoma cell A549 were acquired at this calculated scanning condition, in which the details of surface coarse particle and cell junction structure are visible. This emerging insight into cell profiling may encourage the understanding of the underlying mechanism for cellular inner reconstruction during cell migration.

Thanks to its high operating voltage, the LiNi0.5Mn1.5O4(LNMO) spinel represents a promising next-generation cathode material candidate for Lithium ion batteries. However, LNMO-based full-cells with organic carbonate solvent electrolytes suffer from severe capacity fading issues, associated with electrolyte decomposition and concurrent degradative reactions at the electrode/electrolyte interface, especially at elevated temperatures. As promising alternatives, two selected LiTFSI/pyrrolidinium bis(trifluoromethane-sulfonyl)imide room temperature ionic liquid (RTIL) based electrolytes with inherent thermal stability were investigated in this work. Linear sweep voltammetry (LSV) profiles of the investigated LiTFSI/RTIL electrolytes display much higher oxidative stability compared to the state-of-the-art LiPF6/organic carbonate based electrolyte at elevated temperatures. Cycling performance of the LNMO/Li4Ti5O12(LTO) full-cells with LiTFSI/RTIL electrolytes reveals remarkable improvements with respect to capacity retention and Coulombic efficiency. Scanning electron microscopy (SEM) images and X-ray diffraction (XRD) patterns indicate maintained pristine morphology and structure of LNMO particles after 50 cycles at 0.5C. The investigated LiTFSI/RTIL based electrolytes outperform the LiPF6/organic carbonate-based electrolyte in terms of cycling performance in LNMO/LTO full-cells at elevated temperatures.

Monocrystalline orthorhombic Na0.44MnO2nanoplate as a potential cathode material for sodium-ion batteries has been synthesized by a template-assisted sol-gel method. It exhibits high crystallinity, pure phase and homogeneous size distribution. During the synthesis, acidic and reductive conditions are applied to limit the production of unfavorable Birnessite phase in the precursor, and colloidal polystyrene is included to avoid morphology collapse during the gel formation and particle elongation in one direction. The decompositions of polystyrene and citric acid during high temperature firing offer a reductive carbothermal condition which can suppress the formation of unidimensional particles, and limit particle growth along the [001] direction. As a consequence, the material delivers 96mAhg−1discharge capacity at 10C (86% of 0.1C capacity) and maintains 97.8% capacity after 100 cycles at 0.5C. Such superior rate capability and cycling stability of this material are among the best to date, suggesting its great interest in practical applications.

An evolution panorama of morphology and surface orientation of high-voltage spinel LiNi0.5Mn1.5O4cathode materials synthesized by the combination of the microwave-assisted hydrothermal technique and a postcalcination process is presented. Nanoparticles, octahedral and truncated octahedral particles with different preferential growth of surface orientations are obtained. The structures of different materials are studied by X-ray diffraction (XRD), Raman spectroscopy, X-ray absorption near edge spectroscopy (XANES), and transmission electron microscopy (TEM). The influence of various morphologies (including surface orientations and particle size) on kinetic parameters, such as electronic conductivity and Li+diffusion coefficients, are investigated as well. Moreover, electrochemical measurements indicate that the morphological differences result in divergent rate capabilities and cycling performances. They reveal that appropriate surface-tailoring can satisfy simultaneously the compatibility of power capability and long cycle life. The morphology design for optimizing Li+transport and interfacial stability is very important for high-voltage spinel material. Overall, the crystal chemistry, kinetics and electrochemical performance of the present study on various morphologies of LiNi0.5Mn1.5O4spinel materials have implications for understanding the complex impacts of electrode interface and electrolyte and rational design of rechargeable electrode materials for lithium-ion batteries. The outstanding performance of our truncated octahedral LiNi0.5Mn1.5O4materials makes them promising as cathode materials to develop long-life, high energy and high power lithium-ion batteries.

Background: Surface microstructure of cancerous cell is particularly vital since cell constantly changes its shape as interacting with extracellular matrix and neighboring cells. Atomic force microscope (AFM) has an unparalleled excellence in surface profiling of cells while the scanning quality depends upon experience or experiment conditions primarily. Methods: In this paper, a quadratic regression orthogonal rotation combination design was conducted to obtain optimal parameters of cell scanning via AFM. Results: By iterative calculation, the optimum AFM scanning of cell can be achieved at setpoint of 0.61 V, scanning rate of 2.23 Hz and proportional gain of 3.85. Satisfactory surface morphology images of human bronchial epithelium BEAS- 2B were acquired at this calculated scanning condition, in which the details of surface micro cilia structure and the pore structure are visible. Conclusion: Thus AFM is an effective means for real-time visualization of cell topography in liquid environment and this emerging insight into these cell profiling may promote the understanding of the underlying mechanism for cellular inner reconstruction and cell migration.

In the case where either the potentials Vj, µjand βare periodic or Vjare well-shaped and µjand βare anti-well-shaped, existence of a positive ground state of the Schrödinger system $\left\{ \begin{gathered} - \Delta u_1 + V_1 (x)u_1 = \mu _1 (x)u_1^3 + \beta (x)u_1 u_2^2 in\mathbb{R}^N , \hfill \\ - \Delta u_2 + V_2 (x)u_2 = \beta (x)u_1^2 u_2 + u_2 (x)u_2^3 in\mathbb{R}^N , \hfill \\ u_j \in H^1 (\mathbb{R}^N ),j = 1,2, \hfill \\ \end{gathered} \right.$where N= 1, 2, 3, is proved provided that βis either small or large in terms of Vjand µj. The system with constant coefficients has been studied extensively in the last ten years, and the nonconstant coefficients case has seldom been studied. It turns out that new technical machineries in the setting of variational methods are needed in dealing with the nonconstant coefficients case.

A series of LiNi1/3Co1/3Mn1/3O2 samples are synthesized based on the homogeneous precursors formed in ethanol. The cation mixing, Li+ diffusion ability and high rate capacity of LiNi1/3Co1/3Mn1/3O2 materials are studied by XRD, CV and EIS etc. LNCM-24H presents the lowest cation mixing and a well layered crystal structure. High crystallinity and surface area of LNCM-24H is beneficial to the intercalation/deintercalation of Li+ ions, and lead to a high discharge capacity and good cycle ability. By using an equivalent circuit designed on the real components of lithium battery, the kinetic processes of Li+ diffusion are well simulated. LNCM-24H presents the biggest diffusion coefficient of lithium. At 4.4 V, LNCM-24H delivers capacity of 197.9 mAh g[?]1 and remains 95% of the initial capacity after 50 cycles, compared with 174.3 and 181.7 mAh g[?]1 of LNCM-8H and LNCM-12H, 81% and 84% capacity remained after 50 cycles, respectively. At high current rate of 20 C, LNCM-24H delivers 91.2 mAh g[?]1 (about 47% of the initial capacity at 0.1 C rate). After the first cycle, the coulomb efficiency of charge and discharge is stable at 75%. LNCM-24H presents a very well structural stability during cycling at 20 C rate.

This Communication demonstrates a novel and in situ simultaneous cavitation–doping (SCD) approach to construct bimetallic metal-doped cobalt metal–organic framework hollow nanospheres (CoM-MOF HNSs, with M = Ru or Fe). The key point of the SCD approach is the careful balance between the kinetics of Co-MOF being etched and the coordinative growth of a more stable CoM-MOF shell induced by Lewis acid (MCl3, with M = Ru or Fe). Our work provides a new method to synthesize bimetallic hollow MOFs and benefits the development of electrocatalysts.

Deep placement of nitrogen fertilizer is a key strategy for improving nitrogen use efficiency. A two-year field experiment was conducted during the early rice growing seasons (March–July) of 2016 and 2017. The experimental treatments comprised two rice cultivars: Wufengyou 615 (WFY 615) and Yuxiangyouzhan (YXYZ), and three N treatments: mechanical deep placement of all fertilizers as basal dose at 10 cm soil depth (one-time deep-placement fertilization, namely OTDP fertilization); manual surface broadcast (the common farmer practice) of 40% N fertilizer at one day before sowing (basal fertilizer) followed by broadcast application of 30% each at tillering and panicle initiation stages; and no fertilizer application at any growth stage as a control. One-time deep-placement fertilization increased grain yield of both rice cultivars by 11.8%–19.6%, total nitrogen accumulation by 10.3%–13.1%, nitrogen grain production efficiency by 29.7%–31.5%, nitrogen harvest index by 27.8%–30.0%, nitrogen agronomic efficiency by 71.3%–77.2%, and nitrogen recovery efficiency by 42.4%–56.7% for both rice cultivars, compared with the multiple-broadcast treatment. One-time deep-placement fertilization reduced CH4-induced global warming potential (GWP) by 20.7%–25.3%, N2O-induced GWP by 7.2%–12.3%, and total GWP by 14.7%–22.9% for both rice cultivars relative to the multiple-broadcast treatment. The activities of glutamine synthetase and nitrate reductase were increased at both panicle-initiation and heading stages in both rice cultivars following one-time deep-placement fertilization treatment. Larger leaf area index at heading stage and more favorable root morphological traits expressed as larger total root length, mean root diameter, and total root volume per hill were also observed. One-time deep-placement fertilization could be an effective strategy for increasing grain yield and nitrogen use efficiency and lowering greenhouse-gas emissions under mechanical direct-seeded cropping systems.

Markedly enhanced rate performance of Li-rich (Li1.2Ni0.4/3Co0.4/3Mn1.6/3O2) cathode material is observed after a simple electrochemical pretreatment. The cathode material can deliver discharge capacities of 196, 124 and 86 mAh g[?]1, under current densities of 2, 20 and 40 C, respectively. The capacity retention reaches 60% after 1000 cycles even at 20 C. Analysis of dQ/dV plot and impedance spectroscopy prove that more migration of Ni3+ to Li+ vacancies as well as the higher charge-transfer resistance by a partially insulating Li2O layer, which are created when a slower first charge/discharge rate is applied, result in the capacity loss upon prolonged cycling.

We report the existence and stability properties of multipeaked solitons in a defocusing Kerr medium with an imprinted complex optical lattice featuring a parity-time (PT) symmetry. Various families of soliton solutions with a different number of peaks are found in the first finite gap of the lattice. Linear stability analysis corroborated by direct propagation simulations reveals that multipeaked gap solitons can propagate stably in a wide range, provided that their propagation constant exceeds a critical value. Our findings demonstrate, for the first time, the existence of stable multipeaked gap solitons in a PT-symmetric lattice.

Logistics efficiency is a very important index for measuring the development quality of logistics industry and even region economies. In this paper, the index system upon the logistics efficiency of primary zone of Jilin province were constructed and the logistics efficiency were calculated by Malmquist-Dea Model. The result showed that the logistics efficiency had been generally declining in recent year, the logistics efficiency overall level is not high and the region differences still exist. The results also indicated that the scale efficiency change can promote total factor productivity (TFP) but the technology change hinder the development of TFP.

Micron-sized truncated octahedral LiNi0.5Mn1.5O4(LNMO) samples with different degrees of Ni/Mn disordering have been obtained by controlling the synthesis conditions, such as calcination atmosphere (O2and air), cooling rate or additional annealing step. The influences of Ni/Mn disordering on the physical properties and electrochemical performance of the truncated octahedral LNMO samples have been systematically investigated. The analyses of thermogravimetry, X-ray photoelectron spectroscopy, X-ray diffraction, powder neutron diffraction, Raman spectroscopy and X-ray absorption spectroscopy reveal that the occurrence and degree of Ni/Mn disordering are closely related with the formation of oxygen vacancies and presence of Mn3+. Slow cooling rate and post-annealing can result in low degrees of Ni/Mn disordering and oxygen vacancies. Electrochemical measurements show that Ni/Mn disordering and oxygen vacancies have no obvious effect on the rate capability since all LNMO samples share a truncated octahedral morphology with the exposed {100} surfaces. However, they play significant roles in improving long-term cycling stability, especially at the elevated temperature of 60°C. This work suggests that the electrochemical performance of LNMO with optimized truncated morphology can be further enhanced through tuning the degrees of Ni/Mn disordering and oxygen vacancies.

A series of LiNi1/3Co1/3Mn1/3O2samples are synthesized based on the homogeneous precursors formed in ethanol. The cation mixing, Li+diffusion ability and high rate capacity of LiNi1/3Co1/3Mn1/3O2materials are studied by XRD, CV and EIS etc. LNCM-24H presents the lowest cation mixing and a well layered crystal structure. High crystallinity and surface area of LNCM-24H is beneficial to the intercalation/deintercalation of Li+ions, and lead to a high discharge capacity and good cycle ability. By using an equivalent circuit designed on the real components of lithium battery, the kinetic processes of Li+diffusion are well simulated. LNCM-24H presents the biggest diffusion coefficient of lithium. At 4.4 V, LNCM-24H delivers capacity of 197.9 mAh g−1and remains 95% of the initial capacity after 50 cycles, compared with 174.3 and 181.7 mAh g−1of LNCM-8H and LNCM-12H, 81% and 84% capacity remained after 50 cycles, respectively. At high current rate of 20 C, LNCM-24H delivers 91.2 mAh g−1(about 47% of the initial capacity at 0.1 C rate). After the first cycle, the coulomb efficiency of charge and discharge is stable at 75%. LNCM-24H presents a very well structural stability during cycling at 20 C rate.

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