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81.
82.
Depalo Nicoletta Iacobazzi Rosa Maria Valente Gianpiero Arduino Ilaria Villa Silvia Canepa Fabio Laquintana Valentino Fanizza Elisabetta Striccoli Marinella Cutrignelli Annalisa Lopedota Angela Porcelli Letizia Azzariti Amalia Franco Massimo Curri Maria Lucia Denora Nunzio 《Nano Research》2017,10(7):2431-2448
Currently,sorafenib is the only systemic therapy capable of increasing overall survival of hepatocellular carcinoma patients.Unfortunately,its side effects,particularly its overall toxicity,limit the therapeutic response that can be achieved.Superparamagnetic iron oxide nanoparticles (SPIONs) are very attractive for drug delivery because they can be targeted to specific sites in the body through application of a magnetic field,thus improving intratumoral accumulation and reducing adverse effects.Here,nanoformulations based on polyethylene glycol modified phospholipid micelles,loaded with both SPIONs and sorafenib,were successfully prepared and thoroughly investigated by complementary techniques.This nanovector system provided effective drug delivery,had an average hydrodynamic diameter of about 125 nm,had good stability in aqueous medium,and allowed controlled drug loading.Magnetic analysis allowed accurate determination of the amount of SPIONs embedded in each micelle.An in vitro system was designed to test whether the SPION micelles can be efficiently held using a magnetic field under typical flow conditions found in the human liver.Human hepatocellular carcinoma (HepG2) cells were selected as an in vitro system to evaluate tumor cell targeting efficacy of the superparamagnetic micelles loaded with sorafenib.These experiments demonstrated that this delivery platform is able to enhance sorafenib's antitumor effectiveness by magnetic targeting.The magnetic nanovectors described here represent promising candidates for targeting specific hepatic tumor sites,where selective release of sorafenib can improve its efficacy and safety profile. 相似文献
83.
为了研究罗河铁矿井下爆破振动对地表建筑物的影响,根据该矿的地表环境、爆破参数和爆破振动安全允许标准,采用NUBOX-6016振动监测仪,TP3V-4.5三维速度传感器和BM View软件对地表振动速度和频率进行两次监测。第一次3个点布置在地表离爆点为600 m、650 m、700 m的地方;第二次2个点布置在地表措施井和村庄附近。通过径、切、垂向的监测数据计算出最大合速度为0.757 cm/s,振动频率在30 Hz左右,远小于爆破安全规程所允许范围,得出该矿的爆破振动对地表的建筑物没有破坏作用。根据萨道夫斯基经验公式,用一元回归分析计算出三维方向相应K、α值,得出了三个方向的爆破振动速度预测公式,利用该公式可对今后地表建筑物的安全性进行预测,且为条件类似矿山爆破安全生产提供指导。 相似文献
84.
采用水热法,以磷铁、磷酸、硝酸为原料制备电池级磷酸铁,并利用扫描电镜(SEM)、XRD、红外光谱(FTIR)、TG-DSC以及电化学测试等手段,表征产品的形貌、晶体结构、分子结构和电化学性能,研究了反应过程中硝酸浓度、反应温度、时间及体系浓度对产品性能的影响。实验结果表明:以磷铁为原料,用水热法在一定实验条件下制备的FePO_4·2H_2O产品为正磷酸铁,且产品中含有多种微量金属元素,这有效利用了磷铁中的微量元素,改善了磷酸铁及后续制备的磷酸铁锂的电化学性能。以此为原料通过高温固相法合成的LiFePO_4/C的首次放电容量为148.9mAh/g,具有良好的电化学性能。 相似文献
85.
Jan Tobias Krüger Kay-Peter Hoyer Anatolii Andreiev Mirko Schaper Carolin Zinn 《Advanced Engineering Materials》2023,25(3):2201008
In medical technology, implants are used to improve the quality of patients’ lives. The development of materials with adapted properties can further increase the benefit of implants. If implants are only needed temporarily, biodegradable materials are beneficial. In this context, iron-based materials are promising due to their biocompatibility and mechanical properties, but the degradation rate needs to be accelerated. Apart from alloying, the creation of noble phases to cause anodic dissolution of the iron-based matrix is promising. Due to its high electrochemical potential, immiscibility with iron, biocompatibility, and antibacterial properties, silver is suited for the creation of such phases. A suitable technology for processing immiscible material combinations is powder-bed-based procedure like laser beam melting. This procedure offers short exposure times to high temperatures and therefore a limited time for diffusion of alloying elements. As the silver phases remain after the dissolution of the iron matrix, a modification is needed to ensure their degradability. Following this strategy, pure iron with 5 wt% of a degradable silver–calcium–lanthanum alloy is processed via laser beam melting. Investigation of the microstructure yields achievement of the intended microstructure and long-term degradation tests indicates an impact on the degradation, but no increased degradation rate. 相似文献
86.
Yahuan Huan Tiantian Luo Xiaocang Han Jun Ge Fangfang Cui Lijie Zhu Jingyi Hu Feipeng Zheng Xiaoxu Zhao Lili Wang Jian Wang Yanfeng Zhang 《Advanced materials (Deerfield Beach, Fla.)》2023,35(1):2207276
Exploring new-type 2D magnetic materials with high magnetic transition temperature and robust air stability has attracted wide attention for developing innovative spintronic devices. Recently, intercalation of native metal atoms into the van der Waals gaps of 2D layered transition metal dichalcogenides (TMDs) has been developed to form 2D non-layered magnetic TMDs, while only succeeded in limited systems (e.g., Cr2S3, Cr5Te8). Herein, composition-controllable syntheses of 2D non-layered iron selenide nanosheets (25% Fe-intercalated triclinic Fe5Se8 and 50% Fe-intercalated monoclinic Fe3Se4) are firstly reported, via a robust chemical vapor deposition strategy. Specifically, the 2D Fe5Se8 exhibits intrinsic room-temperature ferromagnetic property, which is explained by the change of electron spin states from layered 1T'-FeSe2 to non-layered Fe-intercalated Fe5Se8 based on density functional theory calculations. In contrast, the ultrathin Fe3Se4 presents novel metallic features comparable with that of metallic TMDs. This work hereby sheds light on the composition-controllable synthesis and fundamental property exploration of 2D self-intercalation induced novel TMDs compounds, by propelling their application explorations in nanoelectronics and spintronics-related fields. 相似文献
87.
本文对比了两种铸铁的机械性能,叙述了铸态球墨铸铁铁路配件的生产,分析了球化处理、孕育处理对配件质量的影响。 相似文献
88.
89.
针对常用的矿仓物位测量方式受粉尘和堆矿死角因素的影响而存在矿仓物位测量不准确的问题,提出了一种新型的矿仓物位测量方案。该方案选择重锤物位计消除粉尘干扰、采用多点布局求取均值的方法消除堆矿死角干扰。实际应用表明,该方案解决了粉尘和堆矿死角对物位测量的影响,降低了矿仓岗位人员的劳动强度。 相似文献
90.
赵昊裔 《计算技术与自动化》2013,(4):100-103
某钢厂第二烧结车间现有90m^2、105m^2的烧结机各一台,担负着2座1000m^3高炉的供矿任务。随着高炉工艺的日益发展以及节能增效的要求,高炉对烧结矿品质的要求越来高。我国生产的烧结矿与国外生产的烧结矿有很大差距,重要原因就在于烧结矿的品质指标波动性太大,这对高炉的炉况来说是很不利的。所以,烧结矿品质预报的研究是很有必要的。 相似文献