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101.
Tianxing Chen Tengteng Yao Hui Peng Andrew K. Whittaker Yao Li Shenmin Zhu Zhaoyang Wang 《Advanced functional materials》2021,31(45):2106079
The convenience of injectable hydrogels that can provide high loading of diverse phototherapy agents and further long-time retention at the tumor site has attracted tremendous interest in simultaneous photothermal and photodynamic cancer therapies. However, to incorporate the phototherapy agents into hydrogels, complex modifications are generally unavoidable. Moreover, these phototherapy agents usually suffer from low efficiency and work at different irradiation wavelengths outside the near infrared windows. Hence, a method for the fabrication of an injectable hydrogel for simultaneous photothermal therapy and photodynamic therapy, through the Schiff-base reaction between amido modified carbon dots (NCDs) and aldehyde modified cellulose nanocrystals is proposed. The NCDs act as both phototherapy agents and crosslinkers to form hydrogels. Significantly, the NCDs demonstrate an extremely high photothermal conversion efficiency of 77.6% which is among the highest levels for photothermal agents and a high singlet quantum yield of 0.37 under a single 660 nm light-emitting diode irradiation. The hydrogels are examined through in vitro and in vivo animal experiments which show nontoxic and effectively tumor inhibition. Thus, the strategy of direct reaction of phototherapy agents and the matrix not only provides new strategies for injectable hydrogel fabrication but paves a new road for advanced tumor treatment. 相似文献
102.
Lingping Kong Jue Gong Qingyang Hu Francesco Capitani Anna Celeste Takanori Hattori Asami Sano-Furukawa Nana Li Wenge Yang Gang Liu Ho-kwang Mao 《Advanced functional materials》2021,31(9):2009131
The soft nature of organic–inorganic halide perovskites renders their lattice particularly tunable to external stimuli such as pressure, undoubtedly offering an effective way to modify their structure for extraordinary optoelectronic properties. Here, using the methylammonium lead iodide as a representative exploratory platform, it is observed that the pressure-driven lattice disorder can be significantly suppressed via hydrogen isotope effect, which is crucial for better optical and mechanical properties previously unattainable. By a comprehensive in situ neutron/synchrotron-based analysis and optical characterizations, a remarkable photoluminescence (PL) enhancement by threefold is convinced in deuterated CD3ND3PbI3, which also shows much greater structural robustness with retainable PL after high peak-pressure compression–decompression cycle. With the first-principles calculations, an atomic level understanding of the strong correlation among the organic sublattice and lead iodide octahedral framework and structural photonics is proposed, where the less dynamic CD3ND3+ cations are vital to maintain the long-range crystalline order through steric and Coulombic interactions. These results also show that CD3ND3PbI3-based solar cell has comparable photovoltaic performance as CH3NH3PbI3-based device but exhibits considerably slower degradation behavior, thus representing a paradigm by suggesting isotope-functionalized perovskite materials for better materials-by-design and more stable photovoltaic application. 相似文献
103.
105.
随着我国社会主义经济的快速发展,我国的建筑工程已经取得了很大进展,建筑企业对于成本控制工作也日益得到了重视。经济成本管理主要包括企业资金的使用规划、流通预测和监督管理等多项内容,是建筑企业重点工作之一,同时也是践行可持续发展目标的基本任务。因此,建筑企业应该加大力度认真地重视建筑成本管理问题,运用各种科学、合理的管理方式和手段,尽可能地最高限度减少资金支出的成本,为建筑企业健康、稳定地生存与发展奠定了重要基础和技术保障。 相似文献
106.
Fenglin Hua Hong Wei Fupeng Ren Mingming Wang Li Li Bolin Lv Huan Wang Zhiwang Yang Ziqiang Lei 《火与材料》2022,46(1):95-106
A novel ternary hybrid flame retardant named P-g-C3N4@PGS-Ti was prepared through step-by-step method. First, titanium dioxide was loaded on PGS to make PGS-Ti (where PGS = palygorskite), and then, PGS-Ti was decorated by phosphor-doped g-C3N4 (abbreviated as P-g-C3N4) to prepare a ternary flame retardant of P-g-C3N4@PGS-Ti. It showed that P-g-C3N4@PGS-Ti could efficiently improve the flame retardancy of epoxy resins (EP). The structure and the morphology of P-C3N4@PGS-Ti were characterized by Fourier transform infrared spectroscopy, X-ray diffraction, scaanning electron microscopy and hermogravimetric analysis (TGA). The flame retardancy and the burning behavior of 5 wt% P-g-C3N4@PGS-Ti composited EP were well investigated through TGA, limiting oxygen index (LOI), cone calorimeter test (CCT) and vertical burning test (UL-94 standard). It was found that the peak heat releasing (pk-HRR) of the EP/P-g-C3N4@PGS-Ti composite reduced 36% (from 1459 to 852 kW/m2) with the addition of 5 wt% of P-g-C3N4@PGS-Ti flame retardant to the matrix of EP. The combustion residue analysis showed that the EP/P-g-C3N4@PGS-Ti composite gained the most continuous and firmest char yield due to the synergistic effect of PGS, TiO2 and the introducing of P element. The mechanism proved that the combination of gas phase and condensed phase flame-retardant processes were well coordinated to improve the fire retardancy for EP. We tested and studied the mechanical properties of EP/P-g-C3N4@PGS-Ti composites. Only 2.4% decreasing of flexural strength and 23.5% decreasing of impact strength in EP/P-g-C3N4@PGS-Ti composites compared to pure EP, respectively. But according to the test results of EP/P-g-C3N4@PGS-Ti composite material and the control sample in the system, EP/P-g-C3N4@PGS-Ti composite material had the highest flexural modulus and impact strength. 相似文献
107.
针对开切眼跨度大造成工作面受到地质灾害的问题,以8702工作面为例,在研究其地质、顶底板情况的基础上,提出开切眼支护的原则,并结合现场情况完成锚杆+锚索+金属网的联合支护参数的设计,最后设计监测方案,对开切眼支护方案的有效性进行验证.实践表明,所采用的的支护方式应用效果良好. 相似文献
108.
为确保重卡变速箱齿轮为其提供高效、稳定动力,保证重卡的性能,着重对单级齿轮的齿轮转速、齿轮箱倾角以及润滑油温度对齿轮的润滑效果基于CFD软件进行仿真研究,同时,对两级齿轮对应的飞溅效果与单级齿轮进行对比.通过上述一系列研究,为重卡变速箱齿轮的设计提供参考和依据. 相似文献
109.
Chuanpeng Li Lunwu Zhang Zhonghai Lu Rui Ding Xiaodong Zhao Bin Wang Hongtao Cui Jie Liu 《工业材料与腐蚀》2021,72(4):732-742
The waterline corrosion behaviors of carbon steel partially immersed in a 3.5 wt% NaCl solution were investigated using the wire beam electrode technique, and the effects of corrosion products on the processes of waterline corrosion were analyzed. The results demonstrated that the initial stage and development stage of waterline corrosion were mainly controlled by the concentration and diffusion of dissolved oxygen, respectively, and the deceleration stage of waterline corrosion was mainly affected by corrosion products. The main component of the yellow corrosion products was γ-FeOOH, and γ-FeOOH that exhibited a high reduction reactivity could be involved in the cathodic reaction. The black corrosion products were mainly composed of Fe3O4 with strong thermodynamic stability and the processes of dissolved oxygen diffusion and ion transports were obviously affected due to the continuous accumulation of Fe3O4 on the surface of the electrodes. Polarity reversals were observed on the single electrodes below the waterline, but the reasons for the phenomena were different from each other. 相似文献
110.
A superhydrophobic ceria-based composite coating is developed to improve anticorrosion properties of AZ61 magnesium alloy, fabricating via chemical conversion method followed by hydrothermal treatment. The cerium conversion coating has a block structure with microcracks. After the hydrothermal treatment, a dense CeO2 layer, porous CeO2 nanorods, and stearic absorbing layers are grown stepwise on the conversion coating. And the composite coating is hydrophobic or even superhydrophobic and has almost no microcracks. As the hydrothermal reaction time increases, the water contact angle of the composite coating first increases and then decreases, and it reaches the maximum value of 152° after hydrothermal treatment for 4 h. Both the dense CeO2 layer and the superhydrophobic stearic absorbing layer can effectively prevent the electrolyte from contacting the substrate; the corrosion current density of the superhydrophobic composite coating is lower than that of the hydrophilic composite coating and the cerium conversion coating, and has the best corrosion resistance. 相似文献