求化学翻译

Graphite powder (<20m)， hydrazine， ammonia， N，Ndimethylformamide (DMF)， dopamine， 0.01M phosphate buffered saline (PBS; 0.138M NaCl， 0.0027M KCl， pH 7.4)， and ascorbic acid were purchased form Aldrich and used as received. Doubly disti... Graphite powder (<20m)， hydrazine， ammonia， N，Ndimethylformamide
(DMF)， dopamine， 0.01M phosphate buffered
saline (PBS; 0.138M NaCl， 0.0027M KCl， pH 7.4)， and ascorbic
acid were purchased form Aldrich and used as received. Doubly
distilled water was used throughout the whole experiments. The
data of cyclic voltammetry (CV)， differential pulse voltammetry
(DPV)， and electrochemical impedance spectra were obtained with
a CHI 660 electrochemical workstation (CH instruments， Austin，
TX). The electrochemical cell consisted of GCE (3mm diameter，
Bioanalytical Systems， Inc.) as working electrode， Ag/AgCl (Bioanalytical
Systems， Inc.) as reference electrode， and platinum
wire as counter electrode. The impedance data were fitted to
an appropriate equivalent circuit using ZsimpWin 3.0 software
(Echem Software).
The Raman spectra of graphene were obtained by micro-Raman
system equipped with a homemade sample stage， a monochromator
(SPEX 500 M)， and a CCD camera (Roger Scientific model
7346-001) with 514.5nm wavelength laser line. Graphene was
characterized by field emission scanning electron microscope
(SUPRA 55VP， Carl Zeiss) and atomic force microscope (NanostationII，
Surface Imaging Systems).