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41.
To overcome high toxicity, low bioavailability and poor water solubility of chemotherapeutics, a variety of drug carriers have been designed. However, most carriers are severely limited by low drug loading capacity and adverse side effects. Here, a new type of metal-drug nanoparticles (MDNs) was designed and synthesized. The MDNs self-assembled with Fe(III) ions and drug molecules through coordination, resulting in nanoparticles with high drug loading. To assist systemic delivery and prolong circulation time, the obtained MDNs were camouflaged with red blood cell (RBCs) membranes (RBCs@Fe-DOX MDNs) to improve their stability and dispersity. The RBCs@Fe-DOX MDNs presented pH-responsive release functionalities, resulting in drug release accelerated in acidic tumor microenvironments. The outstanding in vitro and in vivo antitumor therapeutic outcome was realized by RBCs@Fe-DOX MDNs. This study provides an innovative design guideline for chemotherapy and demonstrates the great capacity of nanomaterials in anticancer treatments.  相似文献   
42.
电感电容损耗电阻的讨论   总被引:3,自引:0,他引:3  
通过对电容电感阻抗的测量,发现实验值偏离理论值。定性地分析了误差的来源,得出的结论是电感电容内部的损耗电阻随着频率的变化而变化,变化方向相反而并非相同。  相似文献   
43.
梁伟山 《化肥工业》2006,33(3):44-47
针对磷酸二铵(DAP)产品养分波动大、含水量偏高、易结块、颜色变化大等缺点,在生产过程中采取了相应的解决措施,如配矿、联产、设备改造、工艺指标调整等,使DAP装置不仅保持了原有的优点,而且产品质量问题也得到了有效解决。养分基本保持在64.0%~64.6%,水分下降到2.1%~2.2%,结块现象较少,颜色也比较统一。  相似文献   
44.
介绍了Kynar-500涂料的涂装工艺,并对涂层的性能作了试验与分析。  相似文献   
45.
Effect of additives on formation of natural gas hydrate   总被引:1,自引:0,他引:1  
C.S Zhang  D.Q Liang  K.H Guo 《Fuel》2004,83(16):2115-2121
The formation of natural gas hydrate (NGH) is studied in this work. Kinetics data of hydrate formation with no agitation were collected at various concentrations of the aqueous solutions with different additives such as alkylpolyglucside, sodium dodecyl benzene sulfonate and potassium oxalate monohydrate. Various kinds of additive increased the formation rates of NGH and its storage capacity and reduced the induction time of NGH formation. Moreover, the storage capacity, the induction time and the hydrate formation rate were influenced by the concentration of the aqueous solution.  相似文献   
46.
Ba0.55Sr0.45TiO3/MgO composites were successfully prepared by the heterogeneous precipitation method and their structural, surface morphological, tunable properties, and dielectric properties at microwave frequency were systemically investigated. Compared with the sample prepared by the traditional solid-state method, the sample prepared by the heterogeneous precipitation method exhibits a smaller grain size, more uniform microstructure, higher tunability, and lower microwave loss, and these properties are very beneficial to the development of the microwave tunable devices application. Moreover, the effects of La2O3 doping on the dielectric and tunable properties of BST/MgO composites are investigated. The result shows that the La3+-doped sample has higher tunability and lower microwave loss than the undoped one.  相似文献   
47.
In this paper, we will extend the strict maximum principle preserving flux limiting technique developed for one dimensional scalar hyperbolic conservation laws to the two-dimensional scalar problems. The parametrized flux limiters and their determination from decoupling maximum principle preserving constraint is presented in a compact way for two-dimensional problems. With the compact fashion that the decoupling is carried out, the technique can be easily applied to high order finite difference and finite volume schemes for multi-dimensional scalar hyperbolic problems. For the two-dimensional problem, the successively defined flux limiters are developed for the multi-stage total-variation-diminishing Runge–Kutta time-discretization to improve the efficiency of computation. The high order schemes with successive flux limiters provide high order approximation and maintain strict maximum principle with mild Courant-Friedrichs-Lewy constraint. Two dimensional numerical evidence is given to demonstrate the capability of the proposed approach.  相似文献   
48.
研制了以工业废渣磷石膏为基材的充填材料.改性后磷石膏的耐水性大大增强,抗压强度≥0.79 MPa、渗透系数≤1×10-5cm.s-1,并且具有合适的C、Φ值.  相似文献   
49.
Summary Three PEO-PSt-PEO triblock polymers and their parent ho-nopolystyrene have been studied by means of light scattering technique in chloroform, toluene and ethyl acetate. It has been found that the weight average molecular weights calculated by using the equation Mapp- were unbelievable negative values; and the largest deviation appeared for the sample with PEO mole content of about 50%. Data of PSt-PEO-PSt triblock polymers in literature have been quoted and discussed.  相似文献   
50.
PPS的共混改性   总被引:2,自引:0,他引:2  
简要介绍了聚苯硫醚(PPS)与其他聚合物进行共混改性的研究进展。着重讨论了PPS PA66、PPS PC、PPS PPO等的共混及其性能。此外,展望了PPS合金的发展前景。  相似文献   
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