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排序方式: 共有155条查询结果,搜索用时 15 毫秒
91.
Progress in electrical energy storage system: A critical review   总被引:4,自引:0,他引:4  
Electrical energy storage technologies for stationary applications are reviewed.Particular attention is paid to pumped hydroelectric storage,compressed air energy storage,battery,flow battery,fuel cell,solar fuel,superconducting magnetic energy storage, flywheel, capacitor/supercapacitor,and thermal energy torage.Comparison is made among these technologies in terms of technical characteris-tics,applications and deployment status.  相似文献   
92.
This paper deals with H control problem for nonlinear conformable fractional order systems. The authors first derive new sufficient condition for exponential stability of nonlinear conformable fractional order systems based on Lyapunov-like function method for conformable fractional order systems and linear matrix inequalities(LMIs) approach. Then, by introducing a new concepts of H control problem for nonlinear conformable fractional order systems, the authors study H performance analysis and H state feedback controller design problems for the considered systems. In terms of LMIs, a sufficient condition is proposed to ensure the nonlinear conformable fractional order systems are not only exponentially stable, but also satisfy H performance γ. An explicit expression for state feedback controllers is also designed to make the closed-loop system is exponentially stable with H_∞performance γ. Finally, numerical examples are given to illustrate the validity and effectiveness of the proposed results.  相似文献   
93.
Preparation and characterization of graphene oxide paper   总被引:7,自引:0,他引:7  
Free-standing paper-like or foil-like materials are an integral part of our technological society. Their uses include protective layers, chemical filters, components of electrical batteries or supercapacitors, adhesive layers, electronic or optoelectronic components, and molecular storage. Inorganic 'paper-like' materials based on nanoscale components such as exfoliated vermiculite or mica platelets have been intensively studied and commercialized as protective coatings, high-temperature binders, dielectric barriers and gas-impermeable membranes. Carbon-based flexible graphite foils composed of stacked platelets of expanded graphite have long been used in packing and gasketing applications because of their chemical resistivity against most media, superior sealability over a wide temperature range, and impermeability to fluids. The discovery of carbon nanotubes brought about bucky paper, which displays excellent mechanical and electrical properties that make it potentially suitable for fuel cell and structural composite applications. Here we report the preparation and characterization of graphene oxide paper, a free-standing carbon-based membrane material made by flow-directed assembly of individual graphene oxide sheets. This new material outperforms many other paper-like materials in stiffness and strength. Its combination of macroscopic flexibility and stiffness is a result of a unique interlocking-tile arrangement of the nanoscale graphene oxide sheets.  相似文献   
94.
The metalloprotease ADAM10 mediates the shedding of the ectodomain of various cell membrane proteins, including APP, the precursor of the amyloid peptide Aβ, and Notch receptors following ligand binding. ADAM10 associates with the members of an evolutionary conserved subgroup of tetraspanins, referred to as TspanC8, which regulate its exit from the endoplasmic reticulum. Here we show that 4 of these TspanC8 (Tspan5, Tspan14, Tspan15 and Tspan33) which positively regulate ADAM10 surface expression levels differentially impact ADAM10-dependent Notch activation and the cleavage of several ADAM10 substrates, including APP, N-cadherin and CD44. Sucrose gradient fractionation, single molecule tracking and quantitative mass-spectrometry analysis of the repertoire of molecules co-immunoprecipitated with Tspan5, Tspan15 and ADAM10 show that these two tetraspanins differentially regulate ADAM10 membrane compartmentalization. These data represent a unique example where several tetraspanins differentially regulate the function of a common partner protein through a distinct membrane compartmentalization.  相似文献   
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97.
Schizophrenia (SCZD) is a debilitating neurological disorder with a world-wide prevalence of 1%; there is a strong genetic component, with an estimated heritability of 80-85%. Although post-mortem studies have revealed reduced brain volume, cell size, spine density and abnormal neural distribution in the prefrontal cortex and hippocampus of SCZD brain tissue and neuropharmacological studies have implicated dopaminergic, glutamatergic and GABAergic activity in SCZD, the cell types affected in SCZD and the molecular mechanisms underlying the disease state remain unclear. To elucidate the cellular and molecular defects of SCZD, we directly reprogrammed fibroblasts from SCZD patients into human induced pluripotent stem cells (hiPSCs) and subsequently differentiated these disorder-specific hiPSCs into neurons (Supplementary Fig. 1). SCZD hiPSC neurons showed diminished neuronal connectivity in conjunction with decreased neurite number, PSD95-protein levels and glutamate receptor expression. Gene expression profiles of SCZD hiPSC neurons identified altered expression of many components of the cyclic AMP and WNT signalling pathways. Key cellular and molecular elements of the SCZD phenotype were ameliorated following treatment of SCZD hiPSC neurons with the antipsychotic loxapine. To date, hiPSC neuronal pathology has only been demonstrated in diseases characterized by both the loss of function of a single gene product and rapid disease progression in early childhood. We now report hiPSC neuronal phenotypes and gene expression changes associated with SCZD, a complex genetic psychiatric disorder.  相似文献   
98.
The sequential timing of cell-cycle transitions is primarily governed by the availability and activity of key cell-cycle proteins. Recent studies in yeast have identified a class of ubiquitin ligases (E3 enzymes) called SCF complexes, which regulate the abundance of proteins that promote and inhibit cell-cycle progression at the G1-S phase transition. SCF complexes consist of three invariable components, Skp1, Cul-1 (Cdc53 in yeast) and Rbx1, and a variable F-box protein that recruits a specific cellular protein to the ubquitin pathway for degradation. To study the role of Cul-1 in mammalian development and cell-cycle regulation, we generated mice deficient for Cul1 and analysed null embryos and heterozygous cell lines. We show that Cul1 is required for early mouse development and that Cul1 mutants fail to regulate the abundance of the G1 cyclin, cyclin E (encoded by Ccne), during embryogenesis.  相似文献   
99.
有机-无机纳米杂化材料是一类重要的功能材料,能够在纳米尺度范围内实现有机材料和无机材料本质的复合,可以获得传统材料所不具有的结构、相态、性能和功能,广泛应用于光电、催化、生物医学等领域.本文着重总结了几类有机-无机纳米杂化材料的制备以及它们在荧光、光声和拉曼生物成像领域的最新研究进展,并对该领域将来的发展方向进行了讨论.  相似文献   
100.
V T Nguyen  T Kiss  A A Michels  O Bensaude 《Nature》2001,414(6861):322-325
  相似文献   
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