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排序方式: 共有5853条查询结果,搜索用时 31 毫秒
1.
A conducting and anticorrosive coating is crucial for the application of metal bipolar plates (BP) in proton exchange membrane fuel cell (PEMFC). In this work, a Ti3C2Tx (T)-carbon black (C)-acrylic epoxy (AE) coating is prepared on 304 stainless steel (SS) with enhanced corrosion resistance and conductivity. The corrosion resistance of the T-C-AE coating is investigated in a 0.5 M H2SO4 solution as compared to the AE, T, and T-AE coatings. The T-C-AE coated 304SS exhibits the strongest corrosion resistance with the most positive corrosion potential and the lowest corrosion current density of 0.00673 μA cm?2 in all the samples, while retaining intact and compact surface morphology with the lowest metal ion dissolution even after immersed for 720 h. The addition of Ti3C2Tx and carbon black into the AE matrix greatly decreases interfacial contact resistance (ICR), and the T-C-AE coating achieves a low ICR of 15.5 mΩ cm?2 under 140 N cm?2 compaction force. The excellent anticorrosion performance is mainly attributed to the physical barrier and the cathodic protection provided by the stacked Ti3C2Tx (MXene) nanosheets in the T-C-AE coating. This eco-friendly, conducting, and anticorrosive T-C-AE coating has a good application prospect on SS BP of PEMFC.  相似文献   
2.
《Ceramics International》2022,48(12):16997-17008
Effective design and fabrication of novel visible light-oriented photocatalysts is an existing challenging task that requires further dedicated efforts, and it has been always a main concern among the scientific community. This study deals with the design and fabrication of an extremely active and ultrafast ternary photocatalyst based on Ag nanoparticles, polypyrrole doped carbon black (PPy-C) and mesoporous TiO2 (m-TiO2). Sol-gel methodology along with sonication and photodeposition routes have been employed for the successful creation of the ternary framework. Ternary photocatalyst composed of uniform spherical titania nanoparticles (10–15 nm in size) perfectly intermingled with the polymeric linkage of PPy-C. Fruitful creation of unique trio photocatalyst between AgNPs, PPy-C and m-TiO2 was confirmed by XPS and XRD. FTIR analysis further supports the development of nanocomposite photocatalyst. TEM analysis showed uniform spherical m-TiO2 nanoparticles (10–15 nm in size) covered by PPy-C with compact nodes like appearance interlocked very well among each other. The newly developed Ag@PPy-C/m-TiO2 ternary photocatalyst exhibited band gap energy in desired visible range of spectra. The photocatalytic efficiency for all created photocatalysts has been evaluated taking Imidacloprid (insecticide derivative) and methylene blue (MB) dye as target pollutants. The novel Ag@PPy-C/m-TiO2 photocatalyst produced astonishing results with ultrafast removal of both Imidacloprid as well MB dye under visible light irradiation. The newly created ultrafast Ag@PPy-C/m-TiO2 photocatalyst has removed 96.0% of the insecticide Imidacloprid in only 25 min with almost ? 2.65 times more efficient than bare m-TiO2 towards the removal of insecticide derivative. The present report offers a highly encouraging and vastly talented Ag@PPy-C/m-TiO2 ternary photocatalyst, enabling the ideal management of extremely lethal and notorious chemicals.  相似文献   
3.
《Ceramics International》2022,48(14):19851-19863
This study aims to develop multifunctionality of cementitious composites with the integrated self-sensing and self-healing capacities by incorporating conductive carbon black (CB) with CB-encapsulated slaked lime (SL). The microsized SL particles were premixed with a half of designed content of nanosized CB particles. When CB agglomerations coat around the SL surfaces, SL does not hydrate until the CB coating is removed. Another half of designed weight of CB is uniformly dispersed using ultrasonication with superplasticizer and added to obtain piezoresistivity. The results show that the stress sensing capacity of CB-SL-cementitious composite performs well with the compressive stress. Autogenous healing performances presented significantly can improve the self-healing capacity with the increase of SL. Furthermore, the healing efficiency is affected by the crack width and dispersion of SL, and the smaller cracks with SL are more easily healed. The size of CB agglomerations decreases with the added SL, and the main product of self-healing is calcium carbonate.  相似文献   
4.
To improve five-year survival rate of oral squamous cell carcinoma (OSCC), the development of a novel composite material of black phosphorus nanosheets (BPNSs) and gold nanoparticles (AuNPs) for tumor treatment was carried out. The purpose of this study is to evaluate the cytostatic effects of BPNSs, AuNPs loaded with cisplatin (CDDP) on human tongue squamous cell carcinoma cells lines (SCC-9), and 7,12-dimethylbenz anthracene induced cheek squamous cell carcinoma was validated in golden hamsters animal models. The results showed that BPNSs could efficiently inhibit the metastasis and growth of OSCC compared with CDDP and AuNPs. And a combination composite of AuNPs–BPNSs loaded with CDDP could more effectively inhibit the metastasis and growth of OSCC, which might be due to the high drug-loading capacity, excellent photothermal properties and the combination of photodynamic and photothermal therapy of BPNSs and AuNPs, as well as the synergistic effects of AuNPs, BPNSs and CDDP.  相似文献   
5.
The present work aims to present the results based on the processing of nanocomposites, which consist of matrix materials like epoxy and filler materials such as conjugated nanomaterials/allotropes of carbon, namely, carbon black, graphite, and multiwalled carbon nanotube (MWCNT) used for targeted applications. To improve the physical and chemical properties and to facilitate a better interfacial interface between the polymer and nanotube, functional MWCNT is used during the preparation of the composite. The prime objective of the study is to establish the thermal, mechanical, and electrical properties of nanocomposites using experimental methods. It has been observed from the experimental results that carbon nanotube (CNT) based composite exhibits higher mechanical (tensile and hardness) and thermal properties as compared with the others. The electrical properties are found to be better in a graphite-based composite. Although CNT has superior mechanical and thermal properties, the exorbitant price limits its use. Hence, the allotropes of carbon may be used judiciously considering both the cost and property requirements of the targeted application. The work also studies the dispersion state of nanofibers through scanning electron microscopy (SEM).  相似文献   
6.
目的研究不同水分工夫红茶贮藏品质变化规律,为工夫红茶贮藏的适宜水分条件提供理论参考。方法系统比较不同水分工夫红茶(国家标准范围内)在自然贮藏条件下其主要内含成分及感官品质的变化。结果 1年贮藏期内,初始水分含量越低,含水率增长速度越快,总体上,茶叶初始水分含量高低决定贮藏过程中水分的高低。在短期贮藏(≤6月)时含水量越高的红茶中茶多酚、水浸出物保留量越多;长期贮藏(6月)时水分较低的红茶中茶多酚、水浸出物保留量越多。咖啡碱、可溶性糖在短期贮藏(≤6月)中水分含量适中的红茶中下降速度越慢;长期贮藏(6月)含水量较高的保留量越高。氨基酸含量在含水量越低的红茶中越高。初始水分含量高的红茶L*、a*、b*值均稍高于水分低的红茶。结论从综合品质的变化来看,本实验中以处理3含水率为5.93%的处理最好,处理2含水率为4.1%次之,处理1含水率为2.33%最差。  相似文献   
7.
《Ceramics International》2020,46(15):23544-23555
This investigation aimed to study the influence of carbon black on the qualifications of TiC-based materials. For this objective, two samples, namely monolithic TiC and TiC-5 wt% carbon black were sintered by spark plasma sintering (SPS) method at 1900 °C. X-ray diffraction (XRD) and field emission scanning electron microscopy (FESEM) were used to characterize the as-sintered samples. Introducing carbon black enhanced the relative density of TiC significantly, reaching a near fully dense substance. Phase analysis and microstructural studies manifested the formation of non-stoichiometric TiCx in both ceramics. Although the introduction of carbonaceous additive considerably increased the thermal conductivity and flexural strength of TiC, standing at 25.1 W/mK and 658 MPa, respectively, its influence on the Vickers hardness was trivial (both ~ 3200 HV0.1 kg). Finally, the composite specimen presented a lower coefficient of friction (~ 0.31) on average compared to the undoped TiC (~ 0.34).  相似文献   
8.
采用含黑色着色剂的涂层浆对尼龙6织物进行湿法涂层,通过测定着色剂在涂层浆中的稳定性及着色剂对涂层织物的着色性和色牢度等性能,研究了黑色着色剂种类、着色剂复配比例及用量、分散剂种类及用量对湿法涂层性能的影响。试验结果表明:炭黑301和中性染料S-RR在湿法涂层中的应用性能较好,并对其进行复配研究,确定中性染料S-RR和炭黑301的复配比例为3∶1,用量为8g;分散剂为TS100,用量为1.0g。  相似文献   
9.
The aim of this study was to evaluate the potency of polyphenolic extract from black radish (Raphanus sativus L. var. niger) root peel waste (PEBRRP) as an antioxidant food additive. PEBRRP was found a powerful antioxidant extract, in which had 172.9 ± 11.5, 462.72 ± 3.05, and 796.51 ± 10.4 mg TE per g dw of total antioxidant capacity (TAC) by CUPRAC, DPPH, and FRAP assays, respectively. The total phenolic content (TPC) and total flavonoid content (TFC) of PEBRRP were found as 305.51 ± 5.2 mg GAE per g dw and 171.58 ± 6.2 mg CAE per g dw, respectively. The ferulic acid (28.02 ± 4.5 mg per g dw) and epicatechin (19.82 ± 3.6 mg per g dw) were identified as the main polyphenols in undigested PEBRRP. The bioaccessibility of total phenolic and total flavonoid compounds of PEBRRP was found approximately 5%, and the antioxidant capacity of bioaccessible PEBRPP fraction was determined 6% in CUPRAC, 36% in DPPH and 47% in FRAP methods.  相似文献   
10.
通过矿相显微镜、扫描电镜、电子探针、X射线能谱元素面分析等多种手段综合研究了川北某黑色页岩型铼矿中铼的赋存状态。样品为黑色页岩,有机碳含量较高。粘土矿物总量为14.6%,黄铁矿含量16.2%,石英含量37.7%。样品具典型的粘土结构,矿物粒度微细。铼有两种赋存状态,一种呈类质同象形式赋存于黄铁矿内,另一种则以分散形式存在。典型黄铁矿测点Re平均含量为0.024%。黄铁矿是Re的重要载体矿物。建议通过浮选分离黄铁矿,从而实现Re的富集。   相似文献   
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