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Lithium (Li) metal, as an appealing candidate for the next-generation of high-energy-density batteries, is plagued by its safety issue mainly caused by uncontrolled dendrite growth and infinite volume expansion. Developing new materials that can improve the performance of Li-metal anode is one of the urgent tasks. Herein, a new MXene derivative containing pure rutile TiO2 and N-doped carbon prepared by heat-treating MXene under a mixing gas, exhibiting high chemical activity in molten Li, is reported. The lithiation MXene derivative with a hybrid of LiTiO2-Li3N-C and Li offers outstanding electrochemical properties. The symmetrical cell assembling lithiation MXene derivative hybrid anode exhibits an ultra-long cycle lifespan of 2000 h with an overpotential of ≈30 mV at 1 mA cm−2, which overwhelms Li-based anodes reported so far. Additionally, long-term operations of 34, 350, and 500 h at 10 mA cm−2 can be achieved in symmetrical cells at temperatures of −10, 25, and 50 °C, respectively. Both experimental tests and density functional theory calculations confirm that the LiTiO2-Li3N-C skeleton serves as a promising host for Li infusion by alleviating volume variation. Simultaneously, the superlithiophilic interphase of Li3N guides Li deposition along the LiTiO2-Li3N-C skeleton to avoid dendrite growth.  相似文献   
3.
JOM - Ti-Mo alloys with various Si alloying additions were prepared by reaction synthesis with Ti powders, Mo powders and Si powders as raw materials. The effect of Si alloying on the...  相似文献   
4.
Black phosphorus(BP),an emerging two-dimensional material,is considered a promising candidate for next-genera-tion electronic and optoelectronic devices due to in-plane anisotropy,high mobility,and direct bandgap.However,BP devices face challenges due to their limited stability,photo-response speed,and detection range.To enhance BP with powerful electric-al and optical performance,the BP heterostructures can be created.In this review,the state-of-the-art heterostructures and their electrical and optoelectronic applications based on black phosphorus are discussed.Five parts introduce the perform-ance of BP-based devices,including black phosphorus sandwich structure by hBN with better stability and higher mobility,black phosphorus homojunction by dual-gate structure for optical applications,black phosphorus heterojunction with other 2D materials for faster photo-detection,black phosphorus heterojunction integration with 3D bulk material,and BP via As-doping tunable bandgap enabling photo-detection up to 8.2 μm.Finally,we discuss the challenges and prospects for BP electric-al and optical devices and applications.  相似文献   
5.
The androgen receptor (AR) plays a crucial role in the occurrence and development of prostate cancer (PCa), and its signaling pathway remains active in castration-resistant prostate cancer (CRPC) patients. The resistance against antiandrogen drugs in current clinical use is a major challenge for the treatment of PCa, and thus the development of new generations of antiandrogens is under high demand. Recently, strategies for downregulating the AR have attracted significant attention, given its potential in the discovery and development of new antiandrogens, including G-quadruplex stabilizers, ROR-γ inhibitors, AR-targeting proteolysis targeting chimeras (PROTACs), and other selective AR degraders (SARDs), which are able to overcome current resistance mechanisms such as acquired AR mutations, the expression of AR variable splices, or overexpression of AR. This review summarizes the various strategies for downregulating the AR protein, at either the mRNA or protein level, thus providing new ideas for the development of promising antiandrogen drugs.  相似文献   
6.
A series of methacrylate-acrylonitrile-butadiene-styrene (MABS) resins was prepared using bulk polymerization. The polarity of the continuous phase and the compatibility of two phases were changed by adjusting the methyl methacrylate (MMA) content, choosing values that were close to styrene-butadiene rubber solubility value. The possibility of controlling the microstructure of the MABS resin by changing the polarity of the components and the compatibility of two phases was assessed. The dynamic mechanical analysis shows that the compatibility of two phases varies with the MMA content. The morphological analysis shows that increasing MMA contents results in a gradual decrease in the sub-inclusion structure with a network skeleton of rubber particles, and that all the particles become solid rubber when the MMA content reaches 75%. The sub-inclusion structure reappears but does not have a network skeleton when the MMA content is 90%. The impact strength and morphological analysis indicate that the solid rubber particles and the sub-inclusion structure with a network skeleton provide excellent toughness, while the sub-inclusion structure without a network skeleton does not. In contrast, the transmittance of the ABS resin first increased and then decreased with increasing MMA content.  相似文献   
7.
本文介绍了一种高准确度质量法液体流量标准装置的设计方法,为对市场中出现的高准确度科里奥利质量流量计的量值传递提供了可能。文中介绍了装置设计过程中,为提高装置准确度用到的电动换向、衡器自校准、蒸馏水代替自来水等方法。试验证明,上述方法的应用使装置达到了预期的不确定度水平。文章还着重介绍了高准确度静态质量法液体流量标准装置不确定度的评价要点,对装置的不确定度水平进行了评定。  相似文献   
8.
运用阳极氧化法制备TiO2纳米管,探讨了TiO2纳米管紫外光催化净化头孢噻肟钠抗生素废水的效果,采用扫描电镜(SEM)和X射线衍射仪(XRD)对TiO2纳米管进行了表征分析。SEM结果显示,制备的TiO2材料表面呈阵列排布的多孔状,内径大小均匀,管径分布在30~45nm之间,管阵列呈蜂窝状,与钛板表面垂直,对比煅烧前后的TiO2纳米管XRD图,发现煅烧后样品的XRD图出现了TiO2锐钛矿型特征衍射峰和金红石型特征衍射峰。讨论了TiO2纳米管的生成机理,认为纳米管的形成过程主要有最初氧化层的形成、孔核的形成、由孔核演变成微孔、微孔生长并出现空隙、形成纳米阵列管过程。  相似文献   
9.
本文采用连续法研究了沸石及凹凸棒石矿物对Cs 的吸附性能,为评价中低放核废物处置效果提供一些参考依据。实验表明:4A沸石对Cs 的平衡吸附量为271mg/g,沸石对Cs 的平衡吸附量为195mg/g,凹凸棒石对Cs 的平衡吸附量为22mg/g;单位质量4A沸石处理0.005mol/L Cs 溶液的能力最强,沸石稍次于4A沸石,凹凸棒石最弱;4A沸石对Cs 的阻滞效果最好,沸石略次之,凹凸棒石最差。  相似文献   
10.
沈晋明  俞卫刚 《暖通空调》2007,37(11):53-59
简要介绍了《建筑环境设计-室内空气质量-人居环境室内空气质量的表述方法》(ISO/DIS16814),它的颁布将会对我国建筑设计产生很大影响和作用。  相似文献   
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