摘要：多硫离子穿梭和锂枝晶生长严重阻碍了锂硫电池的实际应用进程,而合理的隔膜结构可以达到一石二鸟的作用.本工作设计了一种携带有分散性TiN/CoO颗粒的氮掺杂碳纳米管结构(TCCNT),并将其用于锂硫电池隔膜修饰层.TCCNT的多孔结构和表面/内部携带的TiN/CoO颗粒不但实现了对多硫化物的物理、化学吸附和快速催化转化作用,其高导电性的空腔结构和亲锂作用还能够均化锂离子流,在5 mA cm^(-2)的电流密度下实现长达2000 h的均匀锂沉积/剥离过程.TCCNT合理的结构设计有利于各材料组分之间最大限度地发挥协同效应.采用改性隔膜所组装的锂硫电池在常规和高硫载量两种情况下均表现出较好的电化学性能,表明其具有一定的实际应用潜力.

摘要：Nowadays,the number of wireless sensor devices is increasing rapidly,posing persistent challenges related to battery replacement and power *** paper presents a simultaneous wireless information and power transmission(SWIPT)scheme based on a frequency diversity metasurface design,which provides a wireless power supply scheme for electrical devices such as *** metasurface is designed with frequency bands commonly found in the environment,and achieves efficient absorption of electromagnetic(EM)energy at 5.8 GHz and radiation of sensor information at 2.45 GHz,making it possible to take full advantage of the energy in the environment and easy to integrate with existing systems.

摘要：Lithium-sulfur(Li-S) batteries have attracted considerable attention due to their high energy density(2600 Wh kg-1). However, its commercialization is hindered seriously by the low loading and utilization rate of sulfur cathodes. Herein, we designed the cellulose-based graphene carbon composite aerogel(CCA) self-standing electrode to enhance the performance of Li-S batteries. The CCA contributes to the mass loading and utilization efficiency of sulfur, because of its unique physical structure: low density(0.018 g cm-3), large specific surface area(657.85 m2 g-1), high porosity(96%), and remarkable electrolyte adsorption(42.25 times). Compared to Al(about 49%), the CCA displayed excellent sulfur use efficiency(86%) and could reach to high area capacity of 8.60 mAh cm-2 with 9.11 mgS loading. Meanwhile,the CCA exhibits the excellent potential for pulse sensing applications due to its flexibility and superior sensitivity to electrical response signals.

摘要：A novel materials design procedure based on the co-doping of metal nanoparticle and azo dye compound （MNPADC） is developed to improve the properties of functional molecules. The synthesized materials were characterized by transmission electron micrograph （TEM）, ultraviolet-visible absorption spectra （UV-Vis） and fluorescence spectra （FS）. It was found that the fluorescence intensity of methyl orange （MO） was enhanced by 5 times in the aqueous composite system doped with silver nanoparticles whereas it was reduced by 15% and 20% in composite films with co-mixing and coating structures, respectively. The results indicate that the properties of functional molecules can be greatly improved in composite film with supra molecular structure and that the procedure presented here is effective.

摘要：研究了一种货运站场的选址分配问题,它是一类容量受限且需求随机的多设施选址问题。针对该问题提出一种两阶段决策优化方法:第1阶段为选址决策,发生在站场实际建设前;第2阶段为分配决策,发生在站场建设后、实际运营前。选址和分配2个阶段在模型求解时同步完成。基于场景规划理论建立了对应的容量受限型数学模型,该模型的建设费用和运营费用同站场容量成比例,同时约束条件考虑了规划的阶段性需求,更贴近实际情况。设计了采用符号编码策略的遗传算法,算法的编码方式不仅极大缩小了搜索规模和计算复杂度,而且能消除很多遗传算法的实施限制。针对中国的一个国家级枢纽规划问题,应用两阶段优化方法,基于实际统计数据,建立具体的数学模型并运用所设计的算法进行求解,得到不同场景下的选址分配结果,给出了相应的情况分析。

摘要：The development of inexpensive and efficient Pt-free electrocatalysts for the hydrogen evolution reaction(HER)is greatly crucial for water *** carbide(WC)exhibiting a Pt-like electronic structure represents an attractive alternative,although its overall performance is limited by the strong W-H bond that impedes hydrogen ***,we employed an in-situ interface engineering strategy to construct high-performance and cost effective electrocatalysts comprising WC/tungsten phosphide(WP)heterostructures that were anchored on N,P-codoped carbon(WC/WP@NPC)via a one-step pyrolysis of a melamine polyphosphate/WO_(3) hybrid in an inert *** to the crystal structure compatibility and electron-rich property of WP,it optimizes the electronic structure and hydrogen adsorption configuration of WC,thus significantly weakening the W-H bond with a thermoneutral Gibbs free energy of hydrogen adsorption(ΔG_(H^(*)))of−0.05 ***,NPC ensures fast electron transport and structural stability of the WC/WP@NPC ternary *** synergistically lead to outstanding HER performances of the catalyst in acidic and alkaline *** finding offers a new strategy for designing Pt-alternative electrocatalysts with outstanding electrochemical performances for high-efficiency water splitting and other applications.

摘要：理解铁电材料畴结构在低温条件下的翻转行为,对于铁电物理以及其在宽温域的应用都非常重要;然而,目前在低温条件下直接观测介观尺度下的畴翻转仍然面临着巨大的挑战.本论文利用铁酸铋(BiFeO_(3))作为模型来研究3.6–260 K温度范围内的铁电畴翻转行为.菱形相的BiFeO_(3)在温度为130 K时观测到了明显的铁电保持失效现象;这是因为BiFeO_(3)在130 K附近有较大的热释电系数,从而使其升温到该温度附近时释放了大量的热释电电荷,进而产生较强的退极化场,导致铁电极化翻转.另外,本论文还发现通过纳米尺度设计相界可以有效地抑制铁电保持失效.本研究为变温条件下,尤其是低温温域,研究铁电翻转提供了实验范式.

摘要：Near-infrared Ⅱ(NIR-Ⅱ)fluorescent nanoprobes hold great potential for biomedical *** the relationship between surface properties of NIR-Ⅱ nanoprobes and their biological behaviors is particularly important for future probe design and their performance *** the rapid development of NIR-Ⅱ nanoprobes,the distinct role of surface chirality on their biological fates has rarely been ***,chiral NIR-Ⅱ fluorescent Ag_(2)S quantum dots(QDs)are synthesized to investigate the relationship between their chirality and biological functions at both in vitro and in vivo levels.D-/L-Ag_(2)S QDs exhibit significant differences on their interactions with serum proteins,which further affect the cellular *** a result,D-Ag_(2)S QDs can be internalized with higher efficiency(over 2-fold)than that of L-Ag_(2)S ***,in vivo studies reveal that the chirality determines the primary localization of these chiral QDs,where a more efficient renal elimination of D-Ag_(2)S QDs was observed than that of L-Ag_(2)S ***,D-Ag_(2)S QDs show preferential accumulation in tumor region than that of L-Ag_(2)S QDs in orthotopic kidney tumor model,which points out a new avenue of enhancing targeting capabilities of nanoprobes by engineering their surface chirality.

摘要：Gravity and magnetic exploration areas are usually irregular,and there is some data defi *** data must be interpolated before the vertical derivative conversion in the wavenumber ***,for improved processing precision,the data need to be edge-padded to the length required by the fast Fourier transform *** conventional vertical derivative conversion of potential fi eld data(PFD),only vertical derivative conversion is considered,or interpolation,border padding,and vertical derivative conversion are executed *** this paper,these three steps are considered uniformly,and a vertical derivative conversion method for irregular-range PFD based on an improved projection onto convex sets method is *** cutoff wavenumber of the filter used in the proposed method is determined by fractal model fi tting of the radial average power spectrum(RAPS)of the potential fi *** gravity models and real aeromagnetic data show the following:(1)The fitting of the RAPS with a fractal model can separate useful signals and noise reasonably.(2)The proposed iterative method has a clear physical sense,and its interpolation,border padding error,and running time are much smaller than those of the conventional kriging and minimum curvature methods.

摘要：设计钛基金属有机骨架(MOF)实现高效光催化CO_(2)还原具有重要意义但仍极具挑战.本文发展了一种新的一步原位水蚀刻方法制备超细Pd纳米颗粒/多级孔Ti-MOFs高效光催化剂,其中水刻蚀在形成多级孔结构的同时也为Pd的锚定提供了丰富位点,进而在光还原的作用下一步实现Pd纳米颗粒在MOFs表面和内部的负载.得益于多级孔结构和超细Pd颗粒负载,Pd/hMUV-10在350℃光照下的CO产率高达65.9 mmol g^(-1)h^(-1),比目前最先进的MOF基催化剂高出约两个数量级,并超过大多数已报道的无机半导体基催化剂.在200℃相对温和的条件下,CO的产率也达到3.36 mmol g^(-1)h^(-1).在350℃的连续循环测试中,催化剂活性几乎没有衰减.理论计算表明,Pd负载可增强对CO_(2)的吸附和降低CO_(2)还原能垒,从而实现高效光热CO_(2)还原.本文所报道的Pd/hMUV-10催化剂有望在工业CO_(2)捕获和转化中得到应用.