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1.
Int J Biol Macromol ; 256(Pt 2): 128507, 2024 Jan.
Article in English | MEDLINE | ID: mdl-38040144

ABSTRACT

With the increased environmental issues, advanced high-performance and multifunctional polymeric materials derived from biomass have tremendous attention due to the great potential to replace their traditional petroleum-based counterparts. In this work, a series of lignin graft copolymers, lignin-graft-poly(n-butyl acrylate-co-acrylic acid) (Lig-g-P(BA-co-AA)), were rationally prepared via reversible addition-fragmentation chain transfer (RAFT) polymerization. These lignin-based copolymers demonstrate good thermal stability and tunable glass transition temperature (Tg) values. The mechanical performance, including tensile strength, extensibility, Young's modulus, and toughness can be facilely adjusted by the BA/AA feed ratio and lignin content during polymerization. Owing to the extraordinary photothermal conversion ability of lignin, the Lig-B550 copolymer, containing 11.8 wt% lignin content, shows excellent stimulus-healing behavior within 1 min with a 97.1 % healing efficiency under near-infrared (NIR) laser irradiation. Moreover, the Lig-g-P(BA-co-AA) copolymers exhibit remarkable adhesion property, broadening their potential applications in the adhesive area. This grafting strategy is versatile and efficient, conferring the resultant lignin-based composite elastomers with dramatically enhanced mechanical properties and unprecedented photothermal behavior, which can inspire the further development of strong lignin-based sustainable elastomers.


Subject(s)
Elastomers , Lignin , Polymers , Temperature , Transition Temperature
2.
Mater Horiz ; 10(11): 5246-5255, 2023 Oct 30.
Article in English | MEDLINE | ID: mdl-37740481

ABSTRACT

Wadsley-Roth phase niobium titanium oxide (TiNb2O7) is widely regarded as a promising anode candidate for fast-charging lithium-ion batteries due to its safe working potential and doubled capacity in comparison to the commercial fast-charging anode material (lithium titanium oxide, Li4Ti5O12). Although good fast charge/discharge performance was shown for nanostructured TiNb2O7, the small size would cause the low electrode compensation density and energy density of batteries, as well as parasitic reactions. Fundamental understanding of the electrochemical lithium insertion/extraction process and the structural evolution for the micrometer-scale single crystalline TiNb2O7 (MSC-TiNb2O7) could provide insights to understand its inherent properties and possibility for fast-charging application. Here, we revealed the highly reversible structural evolution of the MSC-TiNb2O7 during the lithiation/delithiation processes. Interestingly, an ion-conductive lithium niobate interphase was in situ formed on the MSC-TiNb2O7 surface during the formation cycle, which could facilitate fast ion diffusion on the material surface and support fast electrochemical reaction kinetics. Experimentally, the MSC-TiNb2O7 delivered a high reversible capacity of 291.9 mA h g-1 at 0.5C with a high initial Coulombic efficiency (>95%), and showed superb rate capability with a reasonable capacity of 55.6 mA h g-1 under a high current density of 40C. An Ah-level pouch cell with a lithium cobalt oxide (LiCoO2) cathode exhibited 91.5% capacity retention at 3C charging rate, which revealed the significant role of high crystallinity and in situ formation of an ion conductive nano-interphase in realizing fast charging capability of practical TiNb2O7-based lithium-ion batteries.

3.
Nano Lett ; 23(16): 7485-7492, 2023 Aug 23.
Article in English | MEDLINE | ID: mdl-37477256

ABSTRACT

The recycling of LiFePO4 from degraded lithium-ion batteries (LIBs) from electric vehicles (EVs) has gained significant attention due to resource, environment, and cost considerations. Through neutron diffraction, X-ray photoelectron spectroscopy, and transmission electron microscopy, we revealed continuous lithium loss during battery cycling, resulting in a Li-deficient state (Li1-xFePO4) and phase separation within individual particles, where olive-shaped FePO4 nanodomains (5-10 nm) were embedded in the LiFePO4 matrix. The preservation of the olive-shaped skeleton during Li loss and phase change enabled materials recovery. By chemical compensation for the lithium loss, we successfully restored the hybrid LiFePO4/FePO4 structure to pure LiFePO4, eliminating nanograin boundaries. The regenerated LiFePO4 (R-LiFePO4) exhibited a high crystallinity similar to the fresh counterpart. This study highlights the importance of topotactic chemical reactions in structural repair and offers insights into the potential of targeted Li compensation for energy-efficient recycling of battery electrode materials with polyanion-type skeletons.

4.
Sci Bull (Beijing) ; 67(7): 716-724, 2022 Apr 15.
Article in English | MEDLINE | ID: mdl-36546136

ABSTRACT

Despite the advances of aqueous zinc (Zn) batteries as sustainable energy storage systems, their practical application remains challenging due to the issues of spontaneous corrosion and dendritic deposits at the Zn metal anode. In this work, conformal growth of zinc hydroxide sulfate (ZHS) with dominating (001) facet was realized on (002) plane-dominated Zn metal foil fabricated through a facile thermal annealing process. The ZHS possessed high Zn2+ conductivity (16.9 mS cm-1) and low electronic conductivity (1.28 × 104 Ω cm), and acted as a heterogeneous and robust solid electrolyte interface (SEI) layer on metallic Zn electrode, which regulated the electrochemical Zn plating behavior and suppressed side reactions simultaneously. Moreover, low self-diffusion barrier along the (002) plane promoted the 2D diffusion and horizontal electrochemical plating of metallic Zn for (002)-textured Zn electrode. Consequently, the as-achieved Zn electrode exhibited remarkable cycling stability over 7000 cycles at 2 mA cm-2 and 0.5 mAh cm-2 with a low overpotential of 25 mV in symmetric cells. Pairing with a MnO2 cathode, the as-achieved Zn electrode achieved stable cell cycling with 92.7% capacity retention after 1000 cycles at 10 C with a remarkable average Coulombic efficiency of 99.9%.

5.
Biomater Adv ; 136: 212787, 2022 May.
Article in English | MEDLINE | ID: mdl-35929300

ABSTRACT

Tear protein deposition resistance and antimicrobial property are two challenges of conventional poly(2-hydroxyethyl methacrylate) (pHEMA) contact lenses. In this work, we developed a poly(2-hydroxyethyl methacrylate-co-quaternary ammonium salt chitosan) hydrogel, named as p(HEMA-co-mHACC) hydrogel, using acryloyl HACC (mHACC) as a macromolecular crosslinker. With increasing the acryloyl substitution degree (14-29%) or mHACC content (2-11%), the hydrogel showed an enhanced tensile strength (432-986 kPa) and Young's modulus (360-1158 kPa), a decreased elongation at break (242-84%), and an increased visible light transmittance (0-95%). At an optimal acryloyl substitution degree of 26%, with the increase of mHACC content from 2% to 11%, p(HEMA-co-mHACC) hydrogel presented a decreased water contact angle from 84.6 to 55.3 degree, an increased equilibrium water content from 38% to 45%, and an enhanced oxygen permeability from 8.5 to 13.5 barrer. Due to the enhancement in surface hydrophilicity and electropositivity, p(HEMA-co-mHACC) hydrogel remarkably reduced the deposition of lysozyme, but little affected the adsorption of BSA, depending on the hydrophilic/hydrophobic and electrostatic interactions. The antimicrobial test against Staphylococcus aureus and Escherichia coli showed that p(HEMA-co-mHACC) hydrogel presented an 8-32 times higher germicidal ability than pHEMA hydrogel, indicative of a better antimicrobial activity. The in vitro cell culture of mouse NIH3T3 fibroblasts and immortalized human keratinocytes showed that p(HEMA-co-mHACC) hydrogel was non-toxic. Thus, p(HEMA-co-mHACC) hydrogel with tear protein deposition resistance and antimicrobial activity is a potential candidate for contact lenses.


Subject(s)
Ammonium Compounds , Anti-Infective Agents , Chitosan , Contact Lenses , Animals , Anti-Bacterial Agents/pharmacology , Anti-Infective Agents/pharmacology , Chitosan/pharmacology , Humans , Hydrogels/pharmacology , Methacrylates , Mice , NIH 3T3 Cells , Polyhydroxyethyl Methacrylate/chemistry , Water/chemistry
6.
Angew Chem Int Ed Engl ; 61(14): e202116560, 2022 Mar 28.
Article in English | MEDLINE | ID: mdl-35088500

ABSTRACT

Metallic Zn is a preferred anode material for rechargeable aqueous batteries towards a smart grid and renewable energy storage. Understanding how the metal nucleates and grows at the aqueous Zn anode is a critical and challenging step to achieve full reversibility of Zn battery chemistry, especially under fast-charging conditions. Here, by combining in situ optical imaging and theoretical modeling, we uncover the critical parameters governing the electrodeposition stability of the metallic Zn electrode, that is, the competition among crystallographic thermodynamics, kinetics, and Zn2+ -ion diffusion. Moreover, steady-state Zn metal plating/stripping with Coulombic efficiency above 99 % is achieved at 10-100 mA cm-2 in a reasonably high concentration (3 M) ZnSO4 electrolyte. Significantly, a long-term cycling-stable Zn metal electrode is realized with a depth of discharge of 66.7 % under 50 mA cm-2 in both Zn||Zn symmetrical cells and MnO2 ||Zn full cells.

7.
J Am Chem Soc ; 143(8): 3143-3152, 2021 Mar 03.
Article in English | MEDLINE | ID: mdl-33595314

ABSTRACT

Metal anodes represent as a prime choice for the coming generation rechargeable batteries with high energy density. However, daunting challenges including electrode volume variation and inevitable side reactions preclude them from becoming a viable technology. Here, a facile replacement reaction was employed to fabricate a three-dimensional (3D) interdigitated metal/solid electrolyte composite electrode, which not only provides a stable host structure for buffering the volume change within the composite but also prevents side reactions by avoiding the direct contact between active metal and liquid electrolyte. As a proof-of-concept demonstration, a 3D interdigitated zinc (Zn) metal/solid electrolyte architecture was fabricated via a galvanic replacement reaction between Zn metal foil and indium (In) chloride solution followed by electrochemical activation, featuring the interdigitation between metallic Zn and amorphous indium hydroxide sulfate (IHS) with high Zn2+ conductivity (56.9 ± 1.8 mS cm-1), large Zn2+ transference number (0.55), and high electronic resistivity [(2.08 ± 0.01) × 103 Ω cm]. The as-designed Zn/IHS electrode sustained stable electrochemical Zn plating/stripping over 700 cycles with a record-low overpotential of 8 mV at 1 mA cm-2 and 0.5 mAh cm-2. More impressively, it displayed cycle-stable performance with low overpotential of 10 mV under ultrahigh current density and areal capacity (20 mA cm-2, 20 mAh cm-2), which outperformed all the reported Zn metal electrodes in mild aqueous electrolyte. The fabrication of interdigitated metal/solid electrolyte was generalized to other metal pairs, including Zn/Sn and Zn/Co, which provide inspiration for next-generation Zn metal batteries with high energy density and reversibility.

8.
ACS Appl Mater Interfaces ; 12(20): 23028-23034, 2020 May 20.
Article in English | MEDLINE | ID: mdl-32329612

ABSTRACT

Aqueous rechargeable zinc (Zn) metal batteries show great application prospects in grid-scale energy storage devices due to their good safety, low cost, and considerable energy density. However, the electrical and topographical inhomogeneity caused by the native passivation layer of metallic Zn foil leads to inhomogeneous electrochemical plating and stripping of metallic Zn, and the limited accessible area to the electrolyte of the regular foil electrode causes the poor rate capability, which together hinder the practical application of the Zn metal electrode in rechargeable aqueous batteries. In this work, we show that the native passivation layer on the Zn foil electrode can be removed by a simple chemical polishing strategy, associated with the formation of a three-dimensional ridge-like structure of metallic Zn (r-Zn) on the surface of the Zn foil electrode due to the selective etching of weak crystallographic planes and grain boundary of metallic Zn. The clean and uniform surface of the metallic Zn electrode enables homogeneous plating and stripping of metallic Zn, and the ridge-like structure of r-Zn increases the accessible surface area to the electrolyte and reduces the local current density, which elevates the electrochemical performance of the Zn metal anode with regard to the cycling stability and rate capability. It is demonstrated that a r-Zn anode cycles stably for over 200 h at 1 mA cm-2 and 0.5 mA h cm-2 with a low overpotential of 20 mV, which far outperforms 39 h of cycling with an overpotential of 72 mV for its pristine metallic Zn counterpart.

9.
Neuroreport ; 31(5): 365-371, 2020 03 25.
Article in English | MEDLINE | ID: mdl-31609830

ABSTRACT

OBJECTIVE: Cervical spondylotic myelopathy is regarded as a chronic, special incomplete spinal cord injury, so the sensory components transmitted to thalamus decreased after distal spinal cord injury, which lead the disturbance of thalamus-cortex circuits, which might explain the alterations of clinical function of cervical spondylotic myelopathy patients. However, for lack of effective methods to evaluate the disturbance circuits and how the relative mechanism adapt to the recovery of cervical spondylotic myelopathy patients after decompression. Therefore, this study aim to explore how the possible mechanism of thalamus-cortex circuits reorganization adapt to the recovery of clinical function. METHODS: Regard thalamus as the interest area, we evaluate the brain functional connectivity within 43 pre-operative cervical spondylotic myelopathy patients, 21 post-operative (after 3 months) cervical spondylotic myelopathy patients and 43 healthy controls. Functional connectivity difference between pre-/post-operative cervical spondylotic myelopathy group and healthy controls group were obtained by two independent samples t-test, and difference between pre-operative cervical spondylotic myelopathy and post-operative cervical spondylotic myelopathy group were obtained by paired t-test. Clinical function was measured via Neck Disability Index and Japanese Orthopaedic Association scores. Furthermore, Pearson correlation were used to analyse the correlation between functional connectivity values and clinical scores. RESULTS: Compared with healthy controls group, pre-operative cervical spondylotic myelopathy group showed increased functional connectivity between left thalamus and bilateral lingual gyrus/cuneus/right cerebellum posterior lobe (Voxel P-value <0.01, Cluster P-value <0.05, GRF corrected); post-operative cervical spondylotic myelopathy group manifested decreased functional connectivity between right thalamus and bilateral paracentral lobe/precentral gyrus but significantly increased between right thalamus and pons/superior temporal gyrus. In comparison with pre-operative cervical spondylotic myelopathy group, post-operative cervical spondylotic myelopathy group showed increased functional connectivity between bilateral thalamus and posterior cingulate lobe, angular gyrus, medial prefrontal, but significantly decreased functional connectivity between bilateral thalamus and paracentral lobe/precentral gyrus. The functional connectivity between left thalamus and bilateral lingual gyrus/cuneus/right cerebellum posterior lobe in pre-operative cervical spondylotic myelopathy group have a significantly positive correlation with sensory Japanese Orthopaedic Association scores (r = 0.568, P < 0.001). The functional connectivity between thalamus and paracentral lobe/precentral gyrus in post-operative cervical spondylotic myelopathy group have a significantly positive correlation with upper limb movement Japanese Orthopaedic Association scores (r = 0.448, P = 0.042). CONCLUSION: Pre- or post-operative cervical spondylotic myelopathy patients showed functional connectivity alteration between thalamus and cortex, which suggest adaptive changes may favor the preservation of cortical sensorimotor networks before and after cervical cord decompression, and supply the improvement of clinical function.


Subject(s)
Cervical Vertebrae/physiopathology , Nerve Net/physiopathology , Spinal Cord Diseases/physiopathology , Thalamus/physiopathology , Adult , Decompression , Female , Gyrus Cinguli/physiopathology , Humans , Magnetic Resonance Imaging/methods , Male , Middle Aged
10.
J Virol ; 93(17)2019 09 01.
Article in English | MEDLINE | ID: mdl-31189710

ABSTRACT

Accumulated evidence demonstrates that Japanese encephalitis virus (JEV) infection triggers endoplasmic reticulum (ER) stress and neuron apoptosis. ER stress sensor protein kinase R-like endoplasmic reticulum kinase (PERK) has been reported to induce apoptosis under acute or prolonged ER stress. However, the precise role of PERK in JEV-induced apoptosis and encephalitis remains unknown. Here, we report that JEV infection activates the PERK-ATF4-CHOP apoptosis pathway both in vitro and in vivo PERK activation also promotes the formation of stress granule, which in turn represses JEV-induced apoptosis. However, PERK inhibitor reduces apoptosis, indicating that JEV-activated PERK predominantly induces apoptosis via the PERK-ATF4-CHOP apoptosis pathway. Among JEV proteins that have been reported to induce ER stress, only JEV NS4B can induce PERK activation. PERK has been reported to form an active molecule by dimerization. The coimmunoprecipitation assay shows that NS4B interacts with PERK. Moreover, glycerol gradient centrifugation shows that NS4B induces PERK dimerization. Both the LIG-FHA and the LIG-WD40 domains within NS4B are required to induce PERK dimerization, suggesting that JEV NS4B pulls two PERK molecules together by simultaneously interacting with them via different motifs. PERK deactivation reduces brain cell damage and encephalitis during JEV infection. Furthermore, expression of JEV NS4B is sufficient to induce encephalitis via PERK in mice, indicating that JEV activates PERK primarily via its NS4B to cause encephalitis. Taken together, our findings provide a novel insight into JEV-caused encephalitis.IMPORTANCE Japanese encephalitis virus (JEV) infection triggers endoplasmic reticulum (ER) stress and neuron apoptosis. ER stress sensor protein kinase R-like endoplasmic reticulum kinase (PERK) has been reported to induce apoptosis under acute or prolonged ER stress. However, whether the PERK pathway of ER stress response plays important roles in JEV-induced apoptosis and encephalitis remains unknown. Here, we found that JEV infection activates ER stress sensor PERK in neuronal cells and mouse brains. PERK activation induces apoptosis via the PERK-ATF4-CHOP apoptosis pathway upon JEV infection. Among the JEV proteins prM, E, NS1, NS2A, NS2B, and NS4B, only NS4B activates PERK. Moreover, activated PERK participates in apoptosis and encephalitis induced by JEV and NS4B. These findings provide a novel therapeutic approach for JEV-caused encephalitis.


Subject(s)
Encephalitis Virus, Japanese/pathogenicity , Encephalitis, Japanese/metabolism , Neurons/cytology , Viral Nonstructural Proteins/metabolism , eIF-2 Kinase/metabolism , Activating Transcription Factor 4/metabolism , Adenine/analogs & derivatives , Adenine/pharmacology , Adenine/therapeutic use , Animals , Apoptosis , Binding Sites , Cell Line , Disease Models, Animal , Encephalitis Virus, Japanese/metabolism , Encephalitis, Japanese/virology , Endoplasmic Reticulum Stress , Eukaryotic Initiation Factor-2/metabolism , Indoles/pharmacology , Indoles/therapeutic use , Mice , Neurons/metabolism , Neurons/virology , Protein Multimerization , Signal Transduction , Transcription Factor CHOP/metabolism , Viral Nonstructural Proteins/chemistry , Viral Nonstructural Proteins/genetics , eIF-2 Kinase/chemistry
11.
Zhonghua Zhong Liu Za Zhi ; 32(7): 511-4, 2010 Jul.
Article in Chinese | MEDLINE | ID: mdl-21029694

ABSTRACT

OBJECTIVE: To investigate the prognostic significance of Her-2 expression in node-positive and node-negative breast cancer in Chinese women. METHODS: The Her-2 expression in breast cancers from 981 patients was detected by immunohistochemistry with anti-Her-2 (CB11) monoclonal antibody. The survival curves were analyzed by Kaplan-Meier method, and Cox regression model was applied to determine whether this factor is an independent predictor of survival in multivariate analysis. RESULTS: Nineteen point seven percent of the patients showed positive Her-2 expression in their tumors. Patients with Her-2-positive tumors tended to be younger. The high level Her-2 expression was significantly associated with negative estrogen receptor and progesterone receptor status in their tumors (P < 0.05). Among 387 patients with node-positive disease, the 5-year disease-free survival (DFS) rate and 5-year overall survival (OS) rate were significantly lower in patients with Her-2-positive tumors than in patients with Her-2-negative tumors (DFS: 48.8% vs. 66.9%, P = 0.009; OS: 55.2% vs. 76.4%, P = 0.001), and Her-2 expression was an independent unfavorable prognostic factor for OS, but not for DFS in patients with node-positive disease. Among 591 patients with node-negative disease, Her-2 expression was not significantly associated with DFS and OS (P > 0.05). CONCLUSION: Her-2 expression is an important prognostic factor in patients with node-positive disease, but not for patients with node-negative disease in Chinese women.


Subject(s)
Breast Neoplasms/metabolism , Breast Neoplasms/pathology , Lymph Nodes/pathology , Receptor, ErbB-2/metabolism , Adult , Age Factors , Aged , Aged, 80 and over , Disease-Free Survival , Female , Follow-Up Studies , Gene Expression Regulation, Neoplastic , Humans , Lymphatic Metastasis , Middle Aged , Neoplasm Staging , Proportional Hazards Models , Receptors, Progesterone/metabolism , Survival Rate
12.
Zhonghua Yi Xue Za Zhi ; 88(2): 82-4, 2008 Jan 08.
Article in Chinese | MEDLINE | ID: mdl-18353208

ABSTRACT

OBJECTIVE: To evaluate the utility of ultrasound (US)-guided needle biopsy of ultrasonographic abnormal axillary lymph nodes in the patients with breast cancer. METHODS: The pathological results of US-guided needle biopsy and clinical data of 395 primary breast cancer patients with ultrasonographic abnormal axillary nodes, all female, aged 24 - 83, were analyzed retrospectively. RESULTS: Node metastasis were detected in 277 (70.1%) cases by mean of ultrasound-guided needle biopsy. Among 136 patients with clinical N(0) breast cancer, 65 (47.8%) were proved node positive. Sixty-two patients were diagnosed as pathologically negative by needle biopsy and underwent sentinel lymph node biopsy or axillary lymph node clearance, and pathological examination showed negative axillary lymph node negative. The complete pathological complete remission rate of the metastatic lymph nodes after new adjuvant chemotherapy was 32.3% (62/192). CONCLUSION: Ultrasonographic examination of axilla combined with ultrasound-guided needle biopsy of suspicious axillary node is valuable in primary breast cancer treatment.


Subject(s)
Breast Neoplasms/pathology , Lymph Nodes/pathology , Lymphatic Metastasis/diagnosis , Sentinel Lymph Node Biopsy/methods , Adult , Aged , Aged, 80 and over , Breast Neoplasms/drug therapy , Breast Neoplasms/surgery , Chemotherapy, Adjuvant , Female , Humans , Lymph Nodes/diagnostic imaging , Middle Aged , Neoplasm Staging , Retrospective Studies , Sensitivity and Specificity , Ultrasonography
13.
Zhonghua Wai Ke Za Zhi ; 42(5): 282-4, 2004 Mar 07.
Article in Chinese | MEDLINE | ID: mdl-15062017

ABSTRACT

OBJECTIVE: To discuss the effects of breast-conserving therapy in Chinese women with early primary breast carcinoma. METHODS: Ninety-five patients with stage I to II primary breast cancer were operated with wide local excision and axillary lymph node dissection. After operation, the radiation therapy was done on the whole breast. RESULTS: Breast conservation surgery was taken successfully in ninety-five patients. Six months after operation, the approval rate for their breast was 100% by themselves. Ninety-two per cent of them were very satisfactory. After a median follow-up of 17 months (range 2 - 51 months), only one patient suffered from ipsilateral breast tumor relapse. The two years local relapse rate was 1.4%. There were no cases of distant relapse and death. CONCLUSIONS: The early results of breast-conserving therapy are satisfactory for stage I to II primary breast cancer. The long-term follow-up is needed for the final outcome.


Subject(s)
Breast Neoplasms/surgery , Surgical Procedures, Operative/methods , Adenocarcinoma/radiotherapy , Adenocarcinoma/surgery , Adult , Aged , Breast/pathology , Breast/radiation effects , Breast/surgery , Breast Neoplasms/radiotherapy , Combined Modality Therapy , Female , Follow-Up Studies , Humans , Middle Aged , Recurrence , Treatment Outcome
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