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21.
In the current research, conductive patterns are deposited on different substrates by direct inkjet printing of conductive inks based on metal@carbon and bimetal@carbon core–shell nanoparticles synthesized by the RAPET (reaction under autogenic pressure at elevated temperatures) technique. Various co‐solvents and additives are examined for production of stable conductive ink. The morphology of the deposited layers is characterized by optical and scanning electron microscopy measurements. The stability of the prepared inks is examined by dynamic light scattering measurements. The electrical resistivity is measured by a four‐point probe system and calculated using the geometric dimensions. The results obtained are very promising and indicate that the conductivity of the deposited layers is close to that of bulk metals and higher than most results published so far. Moreover, the importance and advantages of the protective carbon layer that prevents metal oxidation is demonstrated.  相似文献   
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The dependency of free halogen ion oxidation in chemical oxygen demand (COD) assays on the organic content of the sample was investigated. Halogen interference was reduced at increasing glucose or potassium hydrogen phthalate concentration; in each case, a threshold ratio of organic matter to halogen existed, above which halogen oxidation was masked. This ratio depended upon the presence of mercuric sulfate in the case of chloride but not of bromide. It was also affected by the ease of oxidation of both the organic molecule and the halogen ion, as well as by their actual COD. Thus, bromide oxidation was more difficult to prevent than that of chloride, and phthalate exerted a stronger masking effect than glucose.  相似文献   
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We describe and demonstrate a method of digitizing micrographs and a computer analysis method for a quantitative study of thin film morphologies.  相似文献   
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The digestibility of individual cell wall monosaccharide residues from maize silage (MS) and from maize silage + concentrate (MS+con) diets, was examined in sheep equipped with rumen and duodenal cannulas. Dry matter digestibility was 73.8 and 86.6% in the MS and MS+con treatments, respectively. The overall digestibility of cell walls (CW) and CW monosaccharide residues was not depressed in the MS+con treatment. The values for total CW, CW glucose, CW uronic acid and for total xylose were 68.3, 77.0, 71.6 and 65.2 for MS and 69.4, 80.3, 75.3 and 63.7 for MS+con, respectively. However, the digestion of CW and CW monosaccharide residues in the rumen of the MS+con sheep was reduced and the contribution of the lower tract to the digestion of the potentially digestible CW-sugar residues was in the range of 15 to 20%. Digestibility of the soluble uronic acid was adversely affected by the concentrate, its digestibility being reduced from 88.6% in the MS to 68.7% in the MS+con treatment. Based on compositional considerations, it is envisaged that the CW structural unit of the ensiled maize plant is made of cellulose fibres enveloped by a thin, poorly lignified and penetrable matrix. The degree of branching of the matrix polysaccharides is low compared with other forage plants. It is suggested that the above mentioned properties significantly contribute to the high quality of the ensiled maize plant.  相似文献   
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Hybrid organometal halide perovskites are known for their excellent optoelectronic functionality as well as their wide‐ranging chemical flexibility. The composition of hybrid perovskite devices has trended toward increasing complexity as fine‐tuned properties are pursued, including multielement mixing on the constituents A and B and halide sites. However, this tunability presents potential challenges for charge extraction in functional devices. Poor consistency and repeatability between devices may arise due to variations in composition and microstructure. Within a single device, spatial heterogeneity in composition and phase segregation may limit the device from achieving its performance potential. This review details how the nanoscale elemental distribution and charge collection in hybrid perovskite materials evolve as chemical complexity increases, highlighting recent results using nondestructive operando synchrotron‐based X‐ray nanoprobe techniques. The results reveal a strong link between local chemistry and charge collection that must be controlled to develop robust, high‐performance hybrid perovskite materials for optoelectronic devices.  相似文献   
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单分散Ni球制备及Ni/NiO的磁性研究   总被引:1,自引:0,他引:1  
使用微波辅助Poly方法制备了直径范围在100nm~180nm单分散的Ni球,用磁力显微镜(MFM)测其磁结构。进一步对Ni球表面氧化获得了高度球化的NicoreNiOshell结构,采用XRD,TEM,XPS和EDAX对其进行了测量分析,并用VSM和SQUID进一步讨论了铁磁/反铁磁的界面耦合效应。同时,估算了磁性交换偏置耦合场与颗粒尺寸的关系。  相似文献   
29.
Coating of polyethylene (PE), poly(vinyl fluoride) (PVF), poly(tetrafluoroethylene) (PTFE), and poly(vinyl chloride) (PVC) films with flow discharge-polymerized acetylene was investigated. The influence of glow discharge experimental conditions on the nature of the coated layer, the films' wettability, surface roughness, and adhesive joint strength was determined. It was found that coating of these films with plasma-polymerized acetylene led to the formation of a rough, crosslinked, irremovable layer with an improved wettability. The presence of the plasma-polymerized acetylene on the film surface lead to a large improvement in the adhesive joint strength of these films with epoxy adhesive. Best results were obtained with films coated at a low acetylene flow rate. Increase in glow discharge power and treatment time lead to a further improvement.  相似文献   
30.
As little as 0.1 mg boron (1 mg/liter) may be determined in salt solutions containing as much as 400 g/liter MgCl2, MgBr2, NaCl, KCl and CaCl2 or in analytical reagent grade salts with an accuracy of 2% relative. The lower monovalent alcohols do not interfere. The two equivalent points, the gap between them and the role of ionic strength are discussed.  相似文献   
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