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Abstract: A novel facile hydrothermal modification method is applied to improve the electrochemical performance of the low-cost cathode material Li1.231Mn0.615Ni0.154O2, which is primarily prepared by a solid-combustion approach. The material before and after modifying are characterized by energy dispersive spectrometer (EDS), powder X-ray diffraction (XRD), scanning electron microscopy (SEM), BET and high-resolution transmission electron microscopy (HRTEM). The samples are served as the cathode of lithium-ion batteries and investigated by galvanostatic experiments within a voltage range 2.0–4.8 V (vs. Li/Li+). The results reveal that the electrochemical performance of the Li1.231Mn0.615Ni0.154O2 cathode electrode is prominently enhanced after modifying. The significantly improved electrochemical performance of the Li1.231Mn0.615Ni0.154O2 cathode is attributed largely to the modification of the surface microstructure and the crystallinity. [Copyright &y& Elsevier]

Abstract: Carbon coated LiMn0.5Fe0.5PO4 solid solution materials (LiMn0.5Fe0.5PO4/C) are synthesized by rheological phase reaction with stearic acid as carbon source, and characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM), transmission electron microscopy (TEM), BET and TG/DTG. The results show that well-crystallized olivine structure LiMn0.5Fe0.5PO4 nanoplatelets with no obvious impurity phase are obtained. The as-synthesized materials are served as cathode of lithium ion battery and investigated by galvanostatic charge/discharge tests. The results demonstrate that, in comparison with the LMFP materials of different Mn:Fe ratio (LiMn0.2Fe0.8PO4/C and LiMn0.8Fe0.2PO4/C) synthesized by the same route of rheological phase reaction, the LiMn0.5Fe0.5PO4/C exhibit excellent rate specific capability, and can deliver discharge capacity of 138, 99, 80, 72, 67 and 55 mAh g−1 at respectively 0.1, 1, 5, 10, 15 and 20C rates. Moreover, the electrode possesses good cycle stability. A specific capacity of 100 mAh g−1 at 1C after 300 cycles of charge–discharge at room temperature is reached, which represents 95% of capacity retention. The significantly improved electrochemical performances of the LiMn0.5Fe0.5PO4/C cathode are attributed to the uniformly distributed particles and the enhancement of conductivity that is originated from the surface coating of carbon on primary particles. [Copyright &y& Elsevier]

Background: This study was to investigate the effects and safety of cathepsin B-cleavable doxorubicin (DOX)-prodrug (PDOX) for targeting therapy of metastatic human hepatocellular carcinoma (HCC) using DOX as a positive control drug.Methods: The orthotopic nude mice model of highly metastatic HCC was established and the animals were randomized and treated with PDOX, DOX and saline, respectively. Hematology, biochemistry and tumor markers were studied. At autopsy, liver tumor weight and size, ascites, abdominal lymph nodes metastases, experimental peritoneal carcinomatosis index (ePCI), and tumor-host body weight ratio were investigated. Immunohistochemical studies and western blotting were done to investigate key molecules involved in the mechanism of action.Results: Compared with Control, both PDOX and DOX could similarly and significantly reduce liver tumor weight and tumor volume by over 40%, ePCI values, retroperitoneal lymph node metastases and lung metastases and serum AFP levels (P < 0.05). The PDOX group had significantly higher WBC than the DOX group (P < 0.05), and higher PLT than Control (P < 0.05). Serum BUN and Cr levels were lower in the PDOX group than DOX and Control groups (P < 0.05). Compared with Control, DOX increased CK and CK-MB; while PDOX decreased CK compared with DOX (P < 0.05). Multiple spotty degenerative changes of the myocardium were observed in DOX-treated mice, but not in the Control and PDOX groups. PDOX could significantly reduce the Ki-67 positive rate of tumor cells, compared with DOX and Control groups. PDOX produced the effects at least via the ERK pathway.Conclusion: Compared with DOX, PDOX may have better anti-metastatic efficacy and reduced side effects especially cardio-toxicities in this HCC model. [ABSTRACT FROM AUTHOR]

FeS@C-N hierarchical porous microspheres composed of nanosheets were synthesized by a soft-template solvothermal method. The FeS nanoparticles with a diameter of ∼6 nm are coated by amorphous N-doped carbon. When served as anode, the composite displays superior cycling stability and outstanding rate performance in lithium ion batteries. A high capacity of 983.5 mAh g −1 could be delivered after 100 cycles at 100 mA g −1 . And 429.0 mAh g −1 can be maintained during a long-term cycling test of 1800 cycles at 10 A g −1 . The application of FeS@C-N as anode in sodium ion batteries is also investigated with 354.5 mAh g −1 retained after 500 cycles at 100 mA g −1 . And 365.4 mAh g −1 could be obtained at 800 mA g −1 . The enhanced performances could be attributed to the peculiar micro-nano structure including nano-sized particles, one-dimensional nanosheets and porous microspheres. And the study clearly highlights the promising application of FeS@C-N composite in energy storage. [ABSTRACT FROM AUTHOR]

Lithium-rich layered cathodes are known famously for its superior capacity over traditional layered oxides but trapped for lower initial coulombic efficiency, poorer rate capability and worse cyclic stability in spite of diverse attempts. Herein, a new K-stabilized Li-rich layered cathode synthesized through a simple oxalate co-precipitation is reported for its super electrochemical performances. Compared with pristine Li-rich layered cathode, K-stabilized one reaches a higher initial coulombic efficiency of 87% from 76% and outruns for 94% of capacity retention and 244 mAh g −1 of discharge capacity at 0.5C after 100 cycles. Moreover, 133 mAh g −1 of discharge capacity can be delivered even charged at 10C showing a highly-improved rate capability. X-ray diffraction and electrochemical impedance spectroscopy tests show that enlarged Li slab layer caused by K + accommodation can provide facile Li + diffusion paths and facilitate Li + migration from the crystal lattice. As a consequence, the introduction of K + in the host layered structure can inhibit the detrimental spinel structure growth during cycling. Therefore, the K-stabilized Li-rich layered materials can be considered to be an attractive alternative to meet with the higher power and energy density demands of advanced lithium-ion battery. [ABSTRACT FROM AUTHOR]

The present paper reports a synthetic strategy of hierarchical worm-like SnO 2 @C aggregates with enhanced electrochemical performances. Specifically, a glucose-assisted hydrothermal treatment of the intermediate Co–Sn alloy nanoparticles, which were formed by carbothermal reduction of mixed commercial SnO 2 and Co 3 O 4 nanoparticles. The SnO 2 @C sample exhibits enhanced cycling performance in comparison with raw commercial SnO 2 nanoparticles and intermediate Co–Sn alloy nanoparticles when used as anode of lithium ion battery. A stable capacity of 533.6 mA h g −1 at 100 mA g −1 and 477.0 mA h g −1 at 400 mA g −1 remains after 60 cycles. When the current density increases to 1600 mA g −1 , the SnO 2 @C sample still deliver a high capacity of 384.2 mA h g −1 . The superior electrochemical performances could be attributed to the synergistic effect of unique worm-like aggregates structure and carbon surface-layer, which facilitate the electron transportation and buffer the large volume change. [ABSTRACT FROM AUTHOR]

Patients suffering from sepsis-induced acute lung injury (ALI) exhibit a high mortality rate, and their prognosis is closely associated with infiltration of neutrophils into the lungs. In this study, we found a significant elevation of CD64+ neutrophils, which highly expressed p75 neurotrophin receptor (p75NTR) in peripheral blood of mice and patients with sepsis-induced ALI. p75NTR+CD64+ neutrophils were also abundantly expressed in the lung of ALI mice induced by lipopolysaccharide. Conditional knock-out of the myeloid lineage's p75 NTR gene improved the survival rates, attenuated lung tissue inflammation, reduced neutrophil infiltration and enhanced the phagocytic functions of CD64+ neutrophils. In vitro, p75NTR+CD64+ neutrophils exhibited an upregulation and compromised phagocytic activity in blood samples of ALI patients. Blocking p75NTR activity by soluble p75NTR extracellular domain peptide (p75ECD-Fc) boosted CD64+ neutrophils phagocytic activity and reduced inflammatory cytokine production via regulation of the NF-κB activity. The findings strongly indicate that p75NTR+CD64+ neutrophils are a novel pathogenic neutrophil subpopulation promoting sepsis-induced ALI. [Display omitted] • p75NTR+CD64+ neutrophils are upregulated in mice or patients with sepsis-induced ALI. • Genetic deletion or blockade of p75NTR upregulated the phagocytic activity of CD64+ neutrophils in ALI mice. • p75NTR+CD64+ neutrophils are a novel subpopulation of pathogenic neutrophils that promote the sepsis associated with ALI. [ABSTRACT FROM AUTHOR]

Metal sulfides have been intensively investigated for efficient sodium‐ion storage due to their high capacity. However, the mechanisms behind the reaction pathways and phase transformation are still unclear. Moreover, the effects of designed nanostructure on the electrochemical behaviors are rarely reported. Herein, a hydrangea‐like CuS microsphere is prepared via a facile synthetic method and displays significantly enhanced rate and cycle performance. Unlike the traditional intercalation and conversion reactions, an irreversible amorphization process is evidenced and elucidated with the help of in situ high‐resolution synchrotron radiation diffraction analyses, and transmission electron microscopy. The oriented (006) crystal plane growth of the primary CuS nanosheets provide more channels and adsorption sites for Na ions intercalation and the resultant low overpotential is beneficial for the amorphous Cu‐S cluster, which is consistent with the density functional theory calculation. This study can offer new insights into the correlation between the atomic‐scale phase transformation and macro‐scale nanostructure design and open a new principle for the electrode materials' design. [ABSTRACT FROM AUTHOR]

A novel strategy for confined synthesis of graphene wrapped nano-sized LiMn 0.5 Fe 0.5 PO 4 hybrid composite has been developed, including co-precipitation and solvothermal reactions. The LiMn 0.5 Fe 0.5 PO 4 nanoparticles with a constrained diameter of 20 nm are homogeneously wrapped by a continuous interconnected graphene sheets. The mechanism and composite structure evolution during the process are carefully investigated and discussed. With the shortened Li + diffusion paths and enhanced electron conductivity, the hybrid composite shows high discharge capacity and superior rate performance with the discharge capacities of 166 mA h g −1 at 0.1 C and 90 mA h g −1 at 20 C. Excellent cycle stability is also demonstrated with only about 7.8% capacity decay after 500 cycles at 1 C. [ABSTRACT FROM AUTHOR]

[Display omitted] • A new method of phosphate rock magnesium removal in nitric acid was proposed. • The mathematical model of phosphorus and magnesium release in the process of phosphate rock magnesium removal in the nitric acid method was proposed. • The P 2 O 5 loss ratio could be controlled within 1.3–1.4 % with the MgO removal ratio reaching 85 % in the leaching process. As an indispensable part of the process of magnesium extraction from phosphate rock, the kinetics study plays a critical role in fundamental research and industrial production. According to the Arrhenius equation, the activation energy, and the frequency factor of magnesium removal from phosphate rock by a new nitric acid extraction method (nitrate-calcium-nitrate acid-magnesium nitrate) were calculated as 21.83 kJ/mol and 56.01 min−1, respectively. The results suggested that magnesium removal from phosphate rock is under mixed control. Through the derivation of the Fick's law, the kinetic equations of P 2 O 5 loss rate and MgO removal rate were established. The process of magnesium removal from phosphate rock by the nitric acid method is described by the nuclear shrinkage model with constant particle size (η = C 0 + K e - E RT [ p H ] ∑ i 2 α i r i τ ∑ i 2 β i r i r θ), and the root mean square error (RMSE) is 0.12 % and 3.40 %, respectively. Simultaneously, the response surface methodology was taken to investigate the effects of pH, temperature, particle size of phosphate rock, and reaction time on the P 2 O 5 loss ratio and MgO removal ratio, it was found that the P 2 O 5 loss ratio could be controlled within 1.3–1.4 % with the MgO removal ratio reaching 85 %, under the optimized condition when the pH value was 2.0, the temperature was 50 °C, and the particle size of phosphate rock was 0.20–0.22 mm. This work provides an idea for the direct utilization of medium- and low-grade phosphate ore without the flotation method. [ABSTRACT FROM AUTHOR]

A series of xLi1.5Ni0.25Mn0.75O2.5·(1 −x)Li0.5Ni0.25Mn0.75O2 (0 ≤x≤ 1) cathode materials have been synthesized. These compounds exhibit dramatic differences in structure, morphology and charge/discharge characteristics. As the x increases, the morphology shows an amazing trend: starting with an octahedral shape (x = 0), transforming to an octahedral/plate shape (0.1 ≤x≤ 0.9) in which both the spinel phase and the layered phase can be indexed in the XRD patterns, and ending up with a plate shape (x = 1.0). The particular layered-spinel composites xLi1.5Ni0.25Mn0.75O2.5·(1 −x)Li0.5Ni0.25Mn0.75O2 (0.1 ≤x≤ 0.9) exhibit better cycling stability than that of pristine spinel Li0.5Ni0.25Mn0.75O2 (x = 0) and layered Li1.5Ni0.25Mn0.75O2.5 (x = 1.0) materials. This improved cycling performance of these layered-spinel composites can be ascribed to the heterogeneous intergrowth of some layered phases and spinel phases in the parent structure as detected by TEM. Among these materials, Li0.5Ni0.25Mn0.75O2 and Li1.5Ni0.25Mn0.75O2.5 barely deliver the specific capacities of 90 mA h g−1 and 117 mA h g−1 at 5 C and show the capacity retentions of about 83% and 86% at 0.2 C after 50 cycles, respectively, while the layered-spinel 0.8Li1.5Ni0.25Mn0.75O2.5·0.2Li0.5Ni0.25Mn0.75O2 cathode shows the best rate capability of 162 mA h g−1 at 5 C and the best cycling stability of 98% after 50 cycles at 0.2 C. [ABSTRACT FROM AUTHOR]

A series of natural-biogum-deprived carbon composites Si@GAC, Si@GGC and Si@XGC anode materials have been constructed, among which Si@GAC shows the best initial Coulombic efficiency (ICE) resulting from conformal carbon layer containing heteroatoms and covalent interactions with Si core. Based on this result, artificial graphite (AGr) and natural graphite (NGr) are added during the preparation process of Si@GAC to further elevate ICE and cycling stability. This strategy successfully realizes simultaneous and effective improvement of ICE and cycling performance, which could ultimately provide inspiration for high-performance silicon-based anodes. [Display omitted] • Si@C@Graphite materials with enhanced ICE and cycling stability are synthesized. • N, O render dominant capacitive Li+ storage mechanism and faster Li+ transfer. • Artificial graphite better enhances overall electrochemical performance. • Covalently-attached C layer with heteroatoms is conducive to cycling stability. Regarded as one of the most prospective anode materials for lithium-ion batteries (LIBs), silicon (Si) exhibits the highest theoretical capacity (4200 mAh g−1) among various anode materials while generally suffers from huge volume change, resultant rapid capacity fading and low initial Coulombic efficiency (ICE). Here, the ICE and cycling performance of Si-based anode have been simultaneously improved through preparing Si@C@Graphite materials where the conformal carbon modifiers derived from natural biopolymer binders covalently attached to Si particles could enhance the cycling stability, among which GA-derived carbon layer with N, O heteroatoms could best ameliorate the Li+ transport kinetics and thereby rendering superior electrochemical properties, while artificial graphite (AGr) could significantly promote the overall ICE and more effectively elevate the reversible capacity. An excellent ICE (86.4%), a prominent rate performance (1240.6 mAh g−1 at 2000 mA g−1) and a promoted cycling stability (1320.5 mAh g−1 at 800 mA g−1 after 100 cycles) could be presented by Si@GAC@AGr anode. This research provides an effective strategy of simultaneously improving ICE and cycling performance of Si-based anodes and inspires rational design of high-energy–density LIB anodes. [ABSTRACT FROM AUTHOR]

BACKGROUND: Doxorubicin (Adriamycin) is effective in gastric cancer treatment, but with severe dose-dependent toxicities. A novel prodrug of doxorubicin (Ac-Phe-Lys-PABC-ADM) is designed to deliver free doxorubicin relying on cathepsin B and reduce side effects. The authors examined the antitumor effect and toxicities of Ac-Phe-Lys-PABC-ADM against gastric cancer peritoneal carcinomatosis. METHODS: SGC-7901 gastric cancer cell line was used for the study. The in vitro study investigated the effects of doxorubicin and Ac-Phe-Lys-PABC-ADM on cell growth dynamics and cell cycle. The in vivo study investigated the efficacy and toxicity of Ac-Phe-Lys-PABC-ADM on a nude mice model of peritoneal carcinomatosis, with doxorubicin as positive control. RESULTS: In the in vitro study, Ac-Phe-Lys-PABC-ADM had a lower dose-dependent inhibitory effect on SGC-7901 cells. In the in vivo study of control, doxorubicin, and Ac-Phe-Lys-PABC-ADM groups, the median experimental peritoneal carcinomatosis indexes were 6, 1.5, and 1, respectively ( P = .004); the body weights were 24.32 ± 1.40 g, 18.40 ± 2.97 g, and 23.61 ± 0.80 g, respectively ( P = .000). Biochemical studies showed that Ac-Phe-Lys-PABC-ADM had significantly lower toxicities on the bone marrow, liver, kidney, and particularly heart. Histopathological studies of the control, doxorubicin, and Ac-Phe-Lys-PABC-ADM groups found significant myocardium toxicities in 3, 7, and 4 animals, respectively. CONCLUSIONS: Ac-Phe-Lys-PABC-ADM could be an effective molecular targeting drug to treat gastric cancer peritoneal carcinomatosis with enhanced efficacy and reduced toxicity. Cancer 2011. © 2011 American Cancer Society. [ABSTRACT FROM AUTHOR]

Due to the highest theoretical specific capacity of 4200 mA h g−1 for Li 4. 4 Si, silicon(Si)-based materials could fulfill the increasing demands of high-energy lithium-ion batteries (LIBs). However, the intrinsic huge volume expansion during the lithiation/delithiation process results in rapid capacity decay and short cycle life and restricts the satisfactory electrical performance of Si-based anodes. Binder plays an important role of maintaining the contact integrity between active material, conductive additive and the current collector, thereby reducing the pulverization of the Si particles during charge/discharge. Here, the review systematically summarizes the synthesis methods, design principles and working mechanisms, including chemical composition, superstructure, and various interactions between different functional moieties of synthetic binders and natural biomass binders, to reveal the structure-composition-performance relationship, offer practical solutions to challenging problems associated with defects of Si-based electrode materials in LIBs and aim at exploiting new family of binders that could be used in industrial level as well as providing design principles for other electrode binders in rechargeable batteries. Image 1 • Working mechanisms and design principles of Si-based anodes binders are presented. • Synergistic strategy of combining binders with anode structure design is discussed. • Synthesis methods, applied anodes, ICE and cycling performance are listed. [ABSTRACT FROM AUTHOR]