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61.
H. Denissen W. Kalk E. Van Beek C. Löwik S. Papapoulos A. Van Den Hooff 《Journal of materials science. Materials in medicine》1995,6(1):35-40
A composite was made by adsorption of the bisphosphonate [(3-dimethylamino-1-hydroxypropylidene)-1,1-bisphosphonate; dimethyl-APD] into an hydroxyapatite (HA) tube. Adsorbed dimethyl-APD did not change the bulk properties of the HA tube but the surface properties were altered. The amount of 0.1 mmol/L dimethyl-APD adsorbed into the HA tube was 0.78 ( ± 0.20) g after 4 weeks. The composite tube of HA and dimethyl-APD placed after extraction of teeth in the premolar regions of dogs were biocompatible, stable and bonded strongly and intimately to the alveolar bone. Although there was no bone resorption around the composite tubes, no conclusion can be drawn yet from this study as far as local inhibition of alveolar bone resorption is concerned. 相似文献
62.
佛手凉果是具有功能特性的岭南特色凉果品种,探究佛手凉果制作过程中功能性成分及其体外抗氧化活性变化规律,可为佛手凉果产业工艺优化与改良提供依据。结果表明,加工提高了佛手中总酸、多糖、黄酮和膳食纤维含量,导致多酚含量下降。制作过程中,1,1-二苯基-2-三硝基苯(DPPH)自由基、2,20 -联氮- 2 -三硝基苯肼(ABTS)自由基清除能力和铁离子还原抗氧化能力(Ferric Reducing Antioxidant Power, FRAP)呈现先下降后上升的趋势,效果分别是新鲜佛手的1.35倍、1.57倍和2.16倍。总黄酮与FRAP之间呈现极显著相关性(P<0.01);与DPPH、ABTS呈显著相关性(P<0.05);有机酸、总多糖分别与ABTS和FRAP之间相关性(P<0.05)。为此,在佛手凉果的制作过程中,糖制和干燥工艺对功能性成分的转化与浓缩起关键作用,可作为工艺优化的重点。 相似文献
63.
Chuanming Tian Bin Li Yichuan Rui Hao Xiong Yu Zhao Xuefei Han Xinliang Zhou Yu Qiu Wei An Kerui Li Chengyi Hou Yaogang Li Hongzhi Wang Qinghong Zhang 《Advanced functional materials》2023,33(41):2302270
Despite the outstanding power conversion efficiency (PCE) of perovskite solar cells (PSCs) achieved over the years, unsatisfactory stability and lead toxicity remain obstacles that limit their competitiveness and large-scale practical deployment. In this study, in situ polymerizing internal encapsulation (IPIE) is developed as a holistic approach to overcome these challenges. The uniform polymer internal package layer constructed by thermally triggered cross-linkable monomers not only solidifies the ionic perovskite crystalline by strong electron-withdrawing/donating chemical sites, but also acts as a water penetration and ion migration barrier to prolong shelf life under harsh environments. The optimized MAPbI3 and FAPbI3 devices with IPIE treatment yield impressive efficiencies of 22.29% and 24.12%, respectively, accompanied by remarkably enhanced environmental and mechanical stabilities. In addition, toxic water-soluble lead leakage is minimized by the synergetic effect of the physical encapsulation wall and chemical chelation conferred by the IPIE. Hence, this strategy provides a feasible route for preparing efficient, stable, and eco-friendly PSCs. 相似文献
64.
Thanh Hai Nguyen Phan Khanh Linh Tran Van An Dinh Duy Thanh Tran Nam Hoon Kim Joong Hee Lee 《Advanced functional materials》2023,33(7):2210101
Development of multifunctional electrocatalysts with high efficiency and stability is of great interest in recent energy conversion technologies. Herein, a novel heteroelectrocatalyst of molecular iron complex (FeMC)-carbide MXene (Mo2TiC2Tx) uniformly embedded in a 3D graphene-based hierarchical network (GrH) is rationally designed. The coexistence of FeMC and MXene with their unique interactions triggers optimum electronic properties, rich multiple active sites, and favorite free adsorption energy for excellent trifunctional catalytic activities. Meanwhile, the highly porous GrH effectively promotes a multichannel architecture for charge transfer and gas/ion diffusion to improve stability. Therefore, the FeMC–MXene/GrH results in superb performances towards oxygen reduction reaction (ORR), oxygen evolution reaction (OER), and hydrogen evolution reaction (HER) in alkaline medium. The practical tests indicate that Zn/Al–air batteries derived from FeMC–MXene/GrH cathodic electrodes produce high power densities of 165.6 and 172.7 mW cm−2, respectively. Impressively, the liquid-state Zn–air battery delivers excellent cycling stability of over 1100 h. In addition, the alkaline water electrolyzer induces a low cell voltage of 1.55 V at 10 mA cm−2 and 1.86 V at 0.4 A cm−2 in 30 wt.% KOH at 80 °C, surpassing recent reports. The achievements suggest an exciting multifunctional electrocatalyst for electrochemical energy applications. 相似文献
65.
Mobile Networks and Applications - Artificial fish swarm algorithm (AFS) is used in the field of function optimization problems widely. The traditional AFS algorithm has some problems such as long... 相似文献
66.
67.
68.
Xiaoshuai Li Zhengwei Yuan Xiaowei Wei Hui Li Guifeng Zhao Jiaoning Miao Di Wu Bo Liu Songying Cao Dong An Wei Ma Henan Zhang Weilin Wang Qiushi Wang Hui Gu 《Journal of materials science. Materials in medicine》2016,27(4):77
Spina bifida aperta are complex congenital malformations resulting from failure of fusion in the spinal neural tube during embryogenesis. Despite surgical repair of the defect, most patients who survive with spina bifida aperta have a multiple system handicap due to neuron deficiency of the defective spinal cord. Tissue engineering has emerged as a novel treatment for replacement of lost tissue. This study evaluated the prenatal surgical approach of transplanting a chitosan–gelatin scaffold seeded with bone marrow mesenchymal stem cells (BMSCs) in the healing the defective spinal cord of rat fetuses with retinoic acid induced spina bifida aperta. Scaffold characterisation revealed the porous structure, organic and amorphous content. This biomaterial promoted the adhesion, spreading and in vitro viability of the BMSCs. After transplantation of the scaffold combined with BMSCs, the defective region of spinal cord in rat fetuses with spina bifida aperta at E20 decreased obviously under stereomicroscopy, and the skin defect almost closed in many fetuses. The transplanted BMSCs in chitosan–gelatin scaffold survived, grew and expressed markers of neural stem cells and neurons in the defective spinal cord. In addition, the biomaterial presented high biocompatibility and slow biodegradation in vivo. In conclusion, prenatal transplantation of the scaffold combined with BMSCs could treat spinal cord defect in fetuses with spina bifida aperta by the regeneration of neurons and repairmen of defective region. 相似文献
69.
The authors reviewed 53 patients with 70 congenital trigger digits. Three of these were seen at an early age. Most "congenital" trigger digits present later than the neonatal period. A clear difference exists between trigger thumbs and trigger fingers. In our series, thumbs were more frequently affected, 30% were bilateral and none resolved spontaneously. The long fingers were less frequently affected, and two of them (28%) recovered without operation. All other children had an operative release of the A1 pulley of the flexor tendon sheath, with excellent results. 相似文献
70.
在目前的原燃料条件下,为保证马钢2500m3高炉炉渣具有良好的流动性和较高的脱硫能力,炉渣的CaO/SiO2应控制在1.05至1.15之间,炉渣温度不低于1450℃. 相似文献