We report on a micro-Raman investigation of inducing defects in mono-layer, bi-layer and tri-layer graphene by γ ray radiation. It is found that the radiation exposure results in two-dimensional (2D) and G band position evolution with the layer number increasing and D and D' bands rising, suggesting the presence of defects and related crystal lattice deformation in graphene. Bi-layer graphene is more stable than mono- and tri-layer graphene, indicating that the former is a better candidate in the application of radiation environments. Also, the DC electrical property of the mono-layer graphene device shows that the defects increase the carrier density. 相似文献
Correlations of active and passive random intersection graphs are studied in this paper. We present the joint probability
generating function for degrees of Gactive(n, m, p) and Gpassive(n, m, p), which are generated by a random bipartite graph G*(n, m, p) on n + m vertices. 相似文献
The electron temperature (Te) of positive dc corona plasma in Ar/O2 atmosphere was diagnosed, and plasma decomposition of toluene/benzene was studied in a razor–plate reactor. Experimental results revealed that Te would increase with corona current until it reached a peak value, and then decrease; the volume fraction of Ar (φAr) in Ar/O2 mixed gas also influenced Te, the higher φAr, the lower Te. Though the decomposed volume fraction of toluene/benzene was positively related to the input power, the decomposition efficiency did not monotonically increase with the specific energy density. The highest energy yield reached 3.8 g-toluene/kWh and 2.4 g-benzene/kWh, respectively. 相似文献
Based on the property of heterogeneous traffic flow, we in this Letter present a new car-following model. Applying the relationship between the micro and macro variables, a new dynamic model for heterogeneous traffic flow is obtained. The fundamental diagram and the jam density of the heterogeneous traffic flow consisting of bus and car are studied under three different conditions: (1) without any restrictions, (2) under the action of the traffic control policy that restrains some private cars and (3) using bus to replace the private cars restrained by the traffic control policy. The numerical results show that our model can describe some qualitative properties of the heterogeneous traffic flow consisting of bus and car, which verifies that our model is reasonable. 相似文献
Two new bis‐coumarins, namely daphnogitin ( 1 ), daphnogirin ( 2 ), and a flavan‐3‐ol derivative, 5‐O‐methylafzelechin ( 3 ), together with eleven known compounds, daphnetoxin, 1,2‐dihydrodaphnetoxin, daphnetin, daphnoretin, daphneticin, isodaphneticin, trans‐2,3‐dihydro‐3‐(4‐hydroxy‐3‐methoxyphenyl)‐2‐(hydroxymethyl)‐9H‐pyrano[2,3‐f]‐1,4‐benzodioxin‐9‐one (= demethoxyisodaphneticin; 4b ), (+)‐pinoresinol, acuminatin, (−)‐dihydrosesamin, and isosalicifoline, were isolated from the leaves and stems of Daphne giraldii. Compound 4b was isolated for the first time as a natural product, and 1,2‐dihydrodaphnetoxin, daphneticin, isodaphneticin, (+)‐pinoresinol, acuminatin, (−)‐dihydrosesamin, and isosalicifoline were isolated for the first time from Daphne giraldii. The structures of the three new compounds were elucidated by spectroscopic analysis. 相似文献
For new drug candidates with high protein binding in the treatment of diabetic nephropathy, their influence on the protein bindings of angiotensin-converting enzyme inhibitors, sulfonylurea drugs, and angiotensin receptor blockers should be predicted to prevent side effects. To provide an efficient tool for this study, a sensitive and rapid LC–MS–MS method was developed for the simultaneous quantification of representative drugs, benazepril, gliclazide and valsartan in human plasma. Chromatographic separation was performed on a Shim-pack VP-ODS C18 column (250 × 2.0 mm i.d., 5 μm) using methanol–0.05% formic acid (90:10, v/v) as mobile phase. Detection was performed on a triple quadrupole tandem mass spectrometer equipped with an electrospray ionization source and operated in SRM mode. Lower limits of quantification were 2, 2 and 20 ng?1 mL for benazepril, gliclazide and valsartan with 0.1 mL plasma sample. The method fulfills the precision, accuracy, linearity, sensitivity, selectivity requirements to quantify the three drugs and has been successfully used to studying protein binding of benazepril, gliclazide and valsartan in the presence of rhein. 相似文献
Flower power : Unique 3D flower‐like Bi2O3 hierarchical nanostructures were synthesized using a mild aqueous template‐free method (see figure). By introducing VO3? into the reaction system, which mediated the nucleation and growth of Bi2O3, the in situ self‐assembly of 3D hierarchitectures from 2D nanosheets has been realized.
An efficient catalytic asymmetric Friedel–Crafts alkylation of indoles with alkylidene malonates has been developed by using a chiral N,N′‐dioxide–Sc(OTf)3 complex as the catalyst (see scheme). Some optically active intermediates containing the indole skeleton have been synthesized, such as indolepropionic acid, tryptamines, and β‐carbolines. The coordination between the scandium atom and the chiral N,N′‐dioxide compound has been revealed by X‐ray structure analysis.