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1.
Int J Biol Macromol ; 260(Pt 2): 129570, 2024 Mar.
Article in English | MEDLINE | ID: mdl-38246456

ABSTRACT

Sodium lignosulfonate, an abundant natural resource, is regarded as an ideal precursor for the synthesis of hard carbon. The development of high-performance, low-cost and sustainable anode materials is a significant challenge facing lithium-ion batteries (LIBs). The modulation of morphology and defect structure during thermal transformation is crucial to improve Li+ storage behavior. Synthesized using sodium lignosulfonate as a precursor, two-dimensional carbon nanosheets with a high density of defects were produced. The synergistic influence of ice templates and KCl was leveraged, where the ice prevented clumping of potassium chloride during drying, and the latter served as a skeletal support during pyrolysis. This resulted in the formation of an interconnected two-dimensional nanosheet structure through the combined action of both templates. The optimized sample has a charging capacity of 712.4 mA h g-1 at 0.1 A g-1, which is contributed by the slope region. After 200 cycles at 0.2 A g-1, the specific charge capacity remains 514.4 mA h g-1, and a high specific charge capacity of 333.8 mA h g-1 after 800 cycles at 2 A g-1. The proposed investigation offers a promising approach for developing high-performance, low-cost carbon-based anode materials that could be used in advanced lithium-ion batteries.


Subject(s)
Ice , Lignin/analogs & derivatives , Lithium , Crystallization , Carbon
2.
Molecules ; 28(9)2023 Apr 23.
Article in English | MEDLINE | ID: mdl-37175070

ABSTRACT

The surface properties and the hierarchical pore structure of carbon materials are important for their actual application in supercapacitors. It is important to pursue an integrated approach that is both easy and cost-effective but also challenging. Herein, coal-based hierarchical porous carbon with nitrogen doping was prepared by a simple dual template strategy using coal as the carbon precursor. The hierarchical pores were controlled by incorporating different target templates. Thanks to high conductivity, large electrochemically active surface area (483 m2 g-1), hierarchical porousness with appropriate micro-/mesoporous channels, and high surface nitrogen content (5.34%), the resulting porous carbon exhibits a high specific capacitance in a three-electrode system using KOH electrolytes, reaching 302 F g-1 at 1 A g-1 and 230 F g-1 at 50 A g-1 with a retention rate of 76%. At 250 W kg-1, the symmetrical supercapacitor assembled at 6 M KOH shows a high energy density of 8.3 Wh kg-1, and the stability of the cycling is smooth. The energy density of the symmetric supercapacitor assembled under ionic liquids was further increased to 48.3 Wh kg-1 with a power output of 750 W kg-1 when the operating voltage was increased to 3 V. This work expands the application of coal-based carbon materials in capacitive energy storage.

3.
Adv Mater ; 35(50): e2207966, 2023 Dec.
Article in English | MEDLINE | ID: mdl-36353883

ABSTRACT

The interface is the device. As the feature size rapidly shrinks, silicon-based electronic devices are facing multiple challenges of material performance decrease and interface quality degradation. Ultrathin 2D materials are considered as potential candidates in future electronics by their atomically flat surfaces and excellent immunity to short-channel effects. Moreover, due to naturally terminated surfaces and weak van der Waals (vdW) interactions between layers, 2D materials can be freely stacked without the lattice matching limit to form high-quality heterostructure interfaces with arbitrary components and twist angles. Controlled interlayer band alignment and optimized interfacial carrier behavior allow all-2D electronics based on 2D vdW interfaces to exhibit more comprehensive functionality and better performance. Especially, achieving the same computing capacity of multiple conventional devices with small footprint all-2D devices is considered to be the key development direction of future electronics. Herein, the unique properties of all-2D vdW interfaces and their construction methods are systematically reviewed and the main performance contributions of different vdW interfaces in 2D electronics are summarized, respectively. Finally, the recent progress and challenges for all-2D vdW electronics are discussed, and how to improve the compatibility of 2D material devices with silicon-based industrial technology is pointed out as a critical challenge.

4.
PeerJ ; 10: e13497, 2022.
Article in English | MEDLINE | ID: mdl-35646486

ABSTRACT

Aflatoxin B1 (AFB1) is a secondary metabolite produced by the fungus Aspergillus, which is ubiquitous in moldy grain products. Aflatoxin B1 has been reported to possess hepatotoxicity, renal toxicity, and reproductive toxicity. Previous studies have shown that AFB1 is toxic to mammalian oocytes. However, the potential toxicity of AFB1 on the organelles of mouse oocytes is unknown. In this study, we found that exposure to AFB1 significantly reduced mouse oocyte development capacity. Further analysis showed that the endoplasmic reticulum (ER) failed to accumulate around the spindle, and scattered in the cytoplasm under AFB1 exposure. Similar to the ER, the Golgi apparatus showed a uniform localization pattern following AFB1 treatment. In addition, we found that AFB1 exposure caused the condensation of lysosomes in the cytoplasm, presenting as a clustered or spindle peripheral-localization pattern, which indicated that protein modification, transport, and degradation were affected. Mitochondrial distribution was also altered by AFB1 treatment. In summary, our study showed that AFB1 exposure had toxic effects on the distribution of mouse oocyte organelles, which further led to a decline in oocyte quality.


Subject(s)
Aflatoxin B1 , Oocytes , Mice , Animals , Aflatoxin B1/toxicity , Oocytes/metabolism , Oogenesis , Endoplasmic Reticulum , Lysosomes , Mammals
5.
Article in English | MEDLINE | ID: mdl-35682066

ABSTRACT

The Seventh National Population Census, recently conducted in 2020, reported the most up-to-date information on the size, structure, and distribution of China's population. The results showed that the gender imbalance in China is still severe compared with the international standard. With the aim of understanding what has contributed to China's gender imbalance, this study examined a range of potential influencing factors and measured the extent to which they have affected China's sex structure. We gathered data from 3100 citizens (100 surveys from each provincial-level administrative region in mainland China); the useful response rate was 87.5% (2713/3100). We relied on statistical analysis to investigate the phenomenon of male preference in China and used a logit regression to analyze the factors associated with this result. We inspected the factors associated with the perception according to gender, age, annual income, living location, educational level, nationality, family contribution, the ideology of being supported by sons, social status, ability to generate money, and carrying on the family name. The results showed that, among these factors, the relationship of family contribution, the ideology of being supported by sons, and carrying on the family name with male preference was significant. This study is among the first to explore the factors affecting male preference that could have resulted in China's gender imbalance. The findings of this research are also important as references for the development of the population strategy and policy instruments used to manage the demographic problems in China.


Subject(s)
Censuses , Developing Countries , China , Demography , Empirical Research , Humans , Male , Population Dynamics
6.
Article in English | MEDLINE | ID: mdl-35457791

ABSTRACT

This study analyses the effect of air pollution on the settlement intention of migrants in China. In recent years, the willingness of residents to migrate induced by air pollution has received a lot of attention from academics. By matching information from the China Migrants Dynamic Survey from 2015 to 2017 with the air quality index (AQI), we used the Probit model to assess the impact of air pollution on the settlement intentions of migrants with different socioeconomic statuses. First, we demonstrated that air pollution has a significant negative effect on migrants' settlement intention. Second, we found that the effect of air pollution on settlement intention is influenced by individual socioeconomic status; that education level, as an indicator of cognitive ability, affects migrants' motivation to migrate; and that personal income, as an indicator of economic ability, affects the feasibility of their migration. Motivation to migrate and the feasibility of moving determine together the divergence in settlement intention, and those with higher incomes and higher education levels are more likely to leave cities with serious air pollution. Third, the heterogeneous effects suggested that the negative effect of air pollution was greater for older, male, and married migrants. Our findings suggested that air pollution has a variety of effects on the heterogeneous migrants, resulting in changes in the demographic structure of cities.


Subject(s)
Air Pollution , Transients and Migrants , China , Cities , Humans , Intention , Male , Surveys and Questionnaires
7.
Article in English | MEDLINE | ID: mdl-31614417

ABSTRACT

Since 2016, 15 pilot cities in China have implemented a long-term care insurance (LTCI) policy. The aim of this research was to explore the outcomes and evaluate the performance of the LTCI policy in the Chinese pilot cities and estimate the willingness of Chinese citizens to expand the formal implementation of LTCI policy in China. We gathered data from 1500 elderly people aged over 60 years in 15 pilot cities (100 surveys for each city) and the effective response rate was 77.8% (1167/1500). We relied on statistical analysis to elicit the outcomes and performance of LTCI implementation and an ordinal logit regression to analyze the factors associated with the extension of the LTCI policy. We examined factors associated with the perception according to sex, age, degree of disability, choices of care, living location, number of children, and monthly income. Among these factors, the relationship between living location and number of children of the family and the outcomes and performance of the LTCI policy in the pilot cities was significant. The rest of the factors showed no significance with the implementation of the LTCI in Chinese pilot cities. This study is among the first to explore the attitudes of Chinese citizens among those who have benefited from the LTCI policy in the pilot cities and contributes to identifying the outcomes of the LTCI in pilot cities to assist policymakers in their further implementation in China.


Subject(s)
Asian People/psychology , Asian People/statistics & numerical data , Health Knowledge, Attitudes, Practice , Insurance, Long-Term Care/economics , Insurance, Long-Term Care/statistics & numerical data , Long-Term Care/economics , Aged , Aged, 80 and over , China , Cities , Female , Humans , Male , Middle Aged , Pilot Projects
8.
ACS Appl Mater Interfaces ; 10(1): 1266-1277, 2018 Jan 10.
Article in English | MEDLINE | ID: mdl-29227620

ABSTRACT

Interfacial characteristics play an important role in infection prevention and osteointegration of artificial bone implants. In this work, both Ag nanoparticles (AgNPs) and ZnO NPs are incorporated into hydroxyapatite (HA) nanopowders and deposited onto Ti6Al4V (Ti6) implants by laser cladding. The composite coatings possess a hierarchical surface structure with homogeneous distributions of Ag and ZnO. The Ag and ZnO NPs that are immobilized by laser cladding ensure long-term and gradual release of Ag and Zn ions at low cumulative concentrations of 36.2 and 56.4 µg/L after immersion for 21 days. A large concentration of Ag released initially increases the cytotoxicity but the large initial ZnO content enhances the cell viability and osteogenetic ability. The nano Ag/ZnO-embedded HA coating (Ag/ZnO/HA = 7:3:90 wt %, namely Ag7ZnO3HA) exhibits optimal antibacterial efficacy and osteogenetic capability, as exemplified by the broad spectrum antibacterial efficacy of 96.5 and 85.8% against Escherichia coli (E. coli) and Staphylococcus aureus (S. aureus), respectively, together with enhanced osteoinductivity with higher alkaline phosphatase (ALP) activity of 134.60 U/g protein compared to 70.79 U/g protein for the untreated implants after culturing for 7 days. The rabbit femoral implant model further confirms that the optimized composite coating accelerates the formation of new bone tissues indicating 87.15% of the newly formed bone area and osteointegration showing 83.75% of the bone-implant contact area even in the presence of injected S. aureus. The laser-cladded Ag7ZnO3HA composite coatings are promising metallic implants with excellent intrinsic antibacterial activity and osteointegration ability.


Subject(s)
Nanostructures , Animals , Anti-Bacterial Agents , Coated Materials, Biocompatible , Durapatite , Escherichia coli , Rabbits , Silver , Staphylococcus aureus , Zinc Oxide
9.
ACS Appl Mater Interfaces ; 9(31): 26417-26428, 2017 Aug 09.
Article in English | MEDLINE | ID: mdl-28715631

ABSTRACT

Researchers have widely agreed that the broad spectrum antibacterial activity of silver nanoparticles (AgNPs) can be predominantly ascribed to the action of Ag+. This study marks the first report detailing the rapid and highly efficient synergistic bacteria killing of AgNPs, which is achieved by inspiring AgNPs' strong photocatalytic capability to rapidly produce radical oxygen species using 660 nm visible light together with the innate antimicrobial ability of Ag+. These AgNPs were uniformly distributed into well-defined graphene oxide (GO) nanosheets through an in situ reduction of Ag+ and subsequently wrapped with a thin layer of type I collagen. In vivo subcutaneous tests demonstrated that 20 min irradiation of 660 nm visible light could achieve a high antibacterial efficacy of 96.3% and 99.4% on the implant surface against Escherichia coli and Staphylococcus aureus, respectively. In addition, the collagen could reduce the coatings' possible cytotoxicity. The results of this work can provide a highly effective and universal GO-based bioplatform for combination with inorganic antimicrobial NPs (i.e., AgNPs) with excellent photocatalytic properties, which can be utilized for facile and rapid in situ disinfection, as well as long-term prevention of bacterial infection through the synergistic bacteria killing of both 660-nm light-inspired photodynamic action and their innate physical antimicrobial ability.

10.
Sensors (Basel) ; 15(9): 24595-614, 2015 Sep 23.
Article in English | MEDLINE | ID: mdl-26404314

ABSTRACT

Because of the high calculation cost and poor performance of a traditional planar map when dealing with complicated indoor geographic information, a WiFi fingerprint indoor positioning system cannot be widely employed on a smartphone platform. By making full use of the hardware sensors embedded in the smartphone, this study proposes an integrated approach to a three-dimensional (3D) indoor positioning system. First, an improved K-means clustering method is adopted to reduce the fingerprint database retrieval time and enhance positioning efficiency. Next, with the mobile phone's acceleration sensor, a new step counting method based on auto-correlation analysis is proposed to achieve cell phone inertial navigation positioning. Furthermore, the integration of WiFi positioning with Pedestrian Dead Reckoning (PDR) obtains higher positional accuracy with the help of the Unscented Kalman Filter algorithm. Finally, a hybrid 3D positioning system based on Unity 3D, which can carry out real-time positioning for targets in 3D scenes, is designed for the fluent operation of mobile terminals.

11.
Cell Biochem Biophys ; 72(3): 719-26, 2015 Jul.
Article in English | MEDLINE | ID: mdl-25627547

ABSTRACT

Osteosarcoma is a common type of malignant bone tumor with features of osteoid formation or osteolytic lesions of bone. New therapeutic approaches are urgently needed since it lacks response to chemotherapeutic treatments. Saurolactam, a natural compound isolated from the aerial portions of Saururus chinensis, was reported to have an anti-inflammatory activity. Here, we demonstrate that saurolactam shows anti-cancer activity against human osteosarcoma cells. Saurolactam treatment inhibited proliferation of human osteosarcoma cell lines MG-63 and HOS and decreased colony formation in soft agar in a dose-dependent manner. Intraperitoneal administration of saurolactam at 25 mg/kg of body weight for 21 days dramatically inhibited the growth of MG-63 xenografts in nude mice. Flow cytometric analysis indicated that saurolactam treatment (20 µM) led to G1 cell cycle arrest and induced apoptosis in these two cell lines. Western analysis suggested that saurolactam treatment resulted in a reduction of Akt/PKB, phospho-Ser473-Akt, c-Myc, and S-phase kinase-associated protein 2 (Skp2) in MG-63 and HOS osteosarcoma cells. Akt overexpression significantly abolished saurolactam-induced decrease in protein and phosphorylation levels of Akt, c-Myc, and Skp2 protein levels, implying that Akt inactivation was a causal mediator of saurolactam-induced inhibition of c-Myc and Skp2. Moreover, Skp2 overexpression in MG-63 cells partly abolished the growth inhibition induced by saurolactam. Saurolactam treatment repressed migration and invasion ability, and Skp2 overexpression significantly blocked these inhibitory effects of saurolactam in MG-63 Cells. The present study indicates that saurolactam might represent a new promising agent to improve osteosarcoma treatment.


Subject(s)
Antineoplastic Agents/pharmacology , Bone Neoplasms/drug therapy , Cell Movement/drug effects , Cell Proliferation/drug effects , Isoindoles/pharmacology , Osteosarcoma/drug therapy , Animals , Antineoplastic Agents/therapeutic use , Apoptosis/drug effects , Bone Neoplasms/metabolism , Bone Neoplasms/pathology , Cell Line , Humans , Isoindoles/therapeutic use , Male , Mice , Mice, Inbred BALB C , Mice, Nude , Neoplasm Invasiveness , Osteosarcoma/metabolism , Osteosarcoma/pathology , Proto-Oncogene Proteins c-akt/genetics , Proto-Oncogene Proteins c-akt/metabolism , Proto-Oncogene Proteins c-myc/genetics , Proto-Oncogene Proteins c-myc/metabolism , S-Phase Kinase-Associated Proteins/genetics , S-Phase Kinase-Associated Proteins/metabolism
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