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1.
Nat Commun ; 15(1): 6754, 2024 Aug 08.
Article in English | MEDLINE | ID: mdl-39117719

ABSTRACT

Superparaelectrics are considered promising candidate materials for achieving superior energy storage capabilities. However, due to the complicated local structural design, simultaneously achieving high recoverable energy density (Wrec) and energy storage efficiency (η) under high electric fields remains a challenge in bulk superparaelectrics. Here, we propose utilizing entropy engineering to disrupt long-range ferroic orders into local polymorphic distortion disorder with multiple BO6 tilt types and diverse heterogeneous polarization configurations. This strategy reduces the switching barriers, thereby facilitating the emergence of superparaelectric behaviors with ideal polarization forms. Furthermore, it enables high polarization response, negligible remnant polarization, delayed polarization saturation, and enhanced breakdown electric fields (Eb) in high-entropy superparaelectrics. Consequently, an extraordinary Wrec of 15.48 J cm-3 and an ultrahigh η of 90.02% are achieved at a high Eb of 710 kV cm-1, surpassing the comprehensive energy storage performance of previously reported bulk superparaelectrics. This work demonstrates that entropy engineering is a viable strategy for designing high-performance superparaelectrics.

2.
J Agric Food Chem ; 72(26): 14912-14921, 2024 Jul 03.
Article in English | MEDLINE | ID: mdl-38913033

ABSTRACT

Lipase from Rhizopus oryzae (ROL) exhibits remarkable sn-1,3 stereoselectivity and catalytic activity, but its poor thermostability limits its applications in the production of 1,3-dioleoyl-2-palmitoyl glycerol (OPO, a high-quality substitute for human milk fat). In this work, a semirational method was proposed to engineer the thermostability and catalytic activity of 4M (ROL mutant in our previous study). First, a computer-aided design is performed using 4M as a template, and N-glycosylation mutants are then recombinantly expressed and screened in Pichia pastoris, the optimal mutant N227 exhibited a half-life of 298.8 h at 45 °C, which is 7.23-folds longer than that of 4M. Its catalytic activity also reached 1043.80 ± 61.98 U/mg, representing a 29.2% increase compared to 4M (808.02 ± 47.02 U/mg). Molecular dynamics simulations of N227 suggested that the introduction of glycan enhanced the protein rigidity, while the strong hydrogen bonds formed between the glycan and the protein stabilized the lipase structure, thereby improving its thermostability. The acidolysis reaction between oleic acid (OA) and glycerol tripalmitate (PPP) was successfully carried out using immobilized N227, achieving a molar conversion rate of 90.2% for PPP. This engineering strategy guides the modification of lipases, while the glycomutants obtained in this study have potential applications in the biosynthesis of OPO.


Subject(s)
Biocatalysis , Enzyme Stability , Fungal Proteins , Lipase , Rhizopus oryzae , Lipase/chemistry , Lipase/genetics , Lipase/metabolism , Glycosylation , Fungal Proteins/genetics , Fungal Proteins/chemistry , Fungal Proteins/metabolism , Rhizopus oryzae/enzymology , Rhizopus oryzae/genetics , Rhizopus oryzae/chemistry , Rhizopus oryzae/metabolism , Hot Temperature , Kinetics , Rhizopus/enzymology , Rhizopus/genetics
3.
Small ; 20(36): e2400997, 2024 Sep.
Article in English | MEDLINE | ID: mdl-38712477

ABSTRACT

Dielectric capacitors are widely used in advanced electrical and electronic systems due to the rapid charge/discharge rates and high power density. High comprehensive energy storage properties are the ultimate ambition in the field of application achievements. Here, the high-entropy strategy is proposed to design and fabricate single-phase homogeneous (Bi0.5Ba0.1Sr0.1Ca0.2Na0.1)(Fe0.5Ti0.3Zr0.1Nb0.1)O3 ceramic, the hierarchical heterostructure including rhombohedral-tetragonal multiphase nanoclusters and locally disordered oxygen octahedral tilt can lead to the increased dielectric relaxation, diffused phase transition, diverse local polarization configurations, grain refinement, ultrasmall polar nanoregions, large random field, delayed polarization saturation and improved breakdown field. Accordingly, a giant Wrec ≈13.3 J cm-3 and a high η ≈78% at 66.4 kV mm-1 can be simultaneously achieved in the lead-free high-entropy BiFeO3-based ceramic, showing an obvious advantage in overall energy-storage properties over BiFeO3-based lead-free ceramics. Moreover, an ultrafast discharge rate (t0.9 = 18 ns) can be achieved at room temperature, concomitant with favorable temperature stability in the range of 20-160 °C, due to the enhanced diffuse phase transition and fast polarization response. This work provides a feasible pathway to design and generate dielectric materials exhibiting high comprehensive energy-storage performance.

4.
Adv Mater ; 36(21): e2313285, 2024 May.
Article in English | MEDLINE | ID: mdl-38330176

ABSTRACT

Taking into account the need for energy conservation, achieving near-zero energy loss, namely ultrahigh efficiency (η), in energy storage capacitors with large recoverable energy storage density (Wrec) plays an important role in applications, which is one of the major challenges in dielectric energy storage field. Here, guided by phase-field simulation, inhomogeneous polarization configuration with multiple symmetries and polarization magnitudes is controlled through aliovalent strongly polar double ion design to establish a strongly disordered state. A record-high η of ≈97.4% is realized in lead-free relaxors with a large Wrec of ≈8.6 J cm-3, which also give a giant Wrec of ≈11.6 J cm-3 with an ultrahigh η of ≈96.1% through high-energy ball milling, showing a breakthrough progress in ceramic capacitors with a maximum figure of merit of 330. This work demonstrates that controlling inhomogeneous polarization configuration is an effective avenue to develop new high-performance near-zero energy loss energy storage capacitors.

5.
Small ; 19(47): e2303768, 2023 Nov.
Article in English | MEDLINE | ID: mdl-37485639

ABSTRACT

Lead-free dielectric ceramics with excellent energy-storage performance are crucial to the development of the next-generation advanced pulse power capacitors. However, low energy-storage density limits the evolution of capacitors toward lightweight, miniaturization, and integration. Here, an effective strategy of constructing highly dynamic polarization heterogeneous nanoregions is proposed in lead-free relaxors to realize an ultrahigh energy-storage density of ≈8.0 J cm-3 , making almost ten times the growth of energy-storage density compared with pure Bi0.5 Na0.5 TiO3 ceramic, accompanied by a higher energy efficiency of ≈80% as well as an ultrafast discharge rate of ≈20 ns. Ultrasmall polarization heterogeneous nanoregions with different orientations and ultrahigh flexibility, and significantly decreased grain size to submicron lead to reduced heat loss, improved breakdown electric field and polarization, enhanced relaxation, and delayed polarization saturation behaviors, contributing to the remarkable energy-storage performance. Moreover, the breakdown path distribution or electrical tree evolution behaviors are systematically studied to reveal the origin of ultrahigh breakdown electric field through phase field simulations. This work demonstrates that constructing highly dynamic polarization heterogeneous nanoregions is a powerful approach to develop new lead-free dielectric materials with high energy-storage performance.

6.
Nanomicro Lett ; 15(1): 65, 2023 Mar 10.
Article in English | MEDLINE | ID: mdl-36899147

ABSTRACT

Advanced lead-free energy storage ceramics play an indispensable role in next-generation pulse power capacitors market. Here, an ultrahigh energy storage density of ~ 13.8 J cm-3 and a large efficiency of ~ 82.4% are achieved in high-entropy lead-free relaxor ferroelectrics by increasing configuration entropy, named high-entropy strategy, realizing nearly ten times growth of energy storage density compared with low-entropy material. Evolution of energy storage performance and domain structure with increasing configuration entropy is systematically revealed for the first time. The achievement of excellent energy storage properties should be attributed to the enhanced random field, decreased nanodomain size, strong multiple local distortions, and improved breakdown field. Furthermore, the excellent frequency and fatigue stability as well as charge/discharge properties with superior thermal stability are also realized. The significantly enhanced comprehensive energy storage performance by increasing configuration entropy demonstrates that high entropy is an effective but convenient strategy to design new high-performance dielectrics, promoting the development of advanced capacitors .

7.
Adv Mater ; 34(44): e2205787, 2022 Nov.
Article in English | MEDLINE | ID: mdl-36063143

ABSTRACT

Lead-free dielectric ceramics with ultrahigh energy-storage performance are the core components used in next-generation advanced pulse power capacitors. However, the low energy storage density largely hinders their development towards miniaturization, lightweight, and integration. Here, an effective strategy of constructing local diverse polarization is designed in superparaelectrics to realize an ultrahigh energy storage density of ≈10.59 J cm-3 as well as a large efficiency of ≈87.6%. The excellent comprehensive energy-storage performance is mainly attributed to the design of ultrasmall polar nanoregions with local diverse polarization configuration, confirmed by scanning transmission electron microscopy, leading to the reduced heat loss, substantially enhanced polarization, and breakdown electric field compared to ceramics with single polarization configuration. Benefiting from these features, outstanding temperature/frequency/cycling stability and superior charge/discharge performance (power density ≈187.5 MW cm-3 , discharge energy density ≈3.52 J cm-3 , discharge rate ≈77 ns) are also achieved. This work demonstrates that local diverse polarization is a super strategy to design new dielectric materials with high energy-storage performance.

8.
Neuroimmunomodulation ; 26(3): 139-152, 2019.
Article in English | MEDLINE | ID: mdl-31340205

ABSTRACT

OBJECTIVE: Alzheimer's disease (AD) is an age-related devastating neurodegenerative disorder. The hippocampus and cerebral cortex are the most closely related brain regions of cognitive function and neurogenesis. The present study investigated the role of C-terminal-binding protein 1 (CTBP1) in AD. METHODS: AD rat models were established through intracerebroventricular injection of ß-amyloid polypeptide Aß(25-35) and intragastric administration of aluminum chloride solution, and the expression pattern that CTBP1 showed in the hippocampus and cerebral cortex was determined. The learning and memory abilities of AD rats after CTBP1 overexpression were assessed. Hippocampal and cortical neurons were transfected with siRNA against CTBP1 or CTBP1-overexpressing plasmids in order to study the effects of CTBP1 elevation or depletion on neuron morphological changes, apoptosis, and viability. The expression of CTBP1, proapoptotic factor (B-cell lymphoma 2; Bcl-2), and antiapoptotic factors (Bcl-2-associated X protein [Bax] and caspase-3) was subsequently evaluated. RESULTS: CTBP1 was poorly expressed in the hippocampus and cerebral cortex. AD rats displayed enhanced learning and memory abilities following CTBP1 overexpression. Furthermore, overexpression of CTBP1 improved morphological changes of hippocampal and cortical neurons, increased neuron activity, and inhibited neuron apoptosis in AD rats. Moreover, the expression of Bax and caspase-3 decreased, yet Bcl-2 increased. CONCLUSION: Collectively, CTBP1 plays a protective role in the degeneration of hippocampal and cortical neurons whereby overexpressed CTBP1 attenuated the hippocampal and cortical neuron apoptosis and enhanced neuron activity, highlighting the potential of CTBP1 as a target for AD treatment.


Subject(s)
Alzheimer Disease/metabolism , Carrier Proteins/metabolism , Cerebral Cortex/metabolism , Hippocampus/metabolism , Neurons/metabolism , Transcription Factors/metabolism , Alzheimer Disease/pathology , Animals , Apoptosis/physiology , Cerebral Cortex/pathology , Disease Models, Animal , Female , Hippocampus/pathology , Neurons/pathology , Rats , Rats, Sprague-Dawley
9.
Zhonghua Liu Xing Bing Xue Za Zhi ; 36(6): 565-8, 2015 Jun.
Article in Chinese | MEDLINE | ID: mdl-26564625

ABSTRACT

OBJECTIVE: This study was aimed to investigate the ways of spousal notification and its associated factors among HIV discordant couples. METHODS: A face-to-face questionnaire survey was conducted in Henan, Yunnan, Sichuan provinces and Guangxi Zhuang Autonomous Region in China. Information including democratic characteristics, knowledge and behaviors correlated with HIV infections and ways of HIV infectious status notification was collected. 'Data information system' on AIDS prevention and control was used to collect information on the transmission route. RESULTS: A total of 770 pairs of HIV discordant couples were studied, among which 414 (53.77%) HIV positive respondents reported as self-notification, with another 44.68% were notified by medical staff. Factors associated with ways of notification included gender, nation, transmission route, and education level. HIV positive respondents who were female, under Han nationality, being paid blood donors, having had higher education level, were more likely to inform their HIV negative spouse by themselves. CONCLUSION: Nationality and HIV transmission route of the HIV positive individuals were found as significant factors associated with ways of spousal notification. Therefore, HIV discordant couples notification should be strengthened, especially in the Minority-living areas and areas where HIV transmission was predomint through sexual contact and/or via injected drug use.


Subject(s)
HIV Infections/psychology , Interpersonal Relations , Spouses/psychology , Truth Disclosure , China , Female , HIV Infections/transmission , Humans , Male , Minority Groups/psychology , Minority Groups/statistics & numerical data , Sexual Behavior , Spouses/statistics & numerical data , Substance Abuse, Intravenous
10.
Guang Pu Xue Yu Guang Pu Fen Xi ; 25(2): 311-3, 2005 Feb.
Article in Chinese | MEDLINE | ID: mdl-15852886

ABSTRACT

Entrainment swelling consists of occlusion swelling and reliquefaction swelling. Entrainment swelling is significant to industrialized liquid surfactant membrane in the process of operation. The present study based on the life-span of W/O emulsion and O/W emulsion discussed the process of forming entrainment swelling. The result shows that no matter what surface-active agent was used, the life-span of W/O emulsion is 20-88 times longer than that of O/W emulsion. After oil drop was dispersed in water, no swelling was discovered, thus, the ratio of swelling is less than that by other method. The new method of determination of trace mercury by avoiding entrainment swelling in liquid surfactant membrane and FAAS is described. The precision(RSD) and recovery are 1.9%-2.3% and 99.8%-101.1% respectively. Hg2+ at ng x g(-1) level can be enriched and determined. This method can be used in the determination of trace mercury in waste water.


Subject(s)
Emulsions/chemistry , Mercury/analysis , Surface-Active Agents/chemistry , Water Pollutants, Chemical/analysis , Hydrogen-Ion Concentration , Oils/chemistry , Reproducibility of Results , Spectrophotometry, Atomic , Water/chemistry
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