PMID- 30784466
OWN - NLM
STAT- MEDLINE
DCOM- 20190311
LR  - 20190311
IS  - 1001-0742 (Print)
IS  - 1001-0742 (Linking)
VI  - 79
DP  - 2019 May
TI  - Raman spectroscopy of diesel and gasoline engine-out soot using different laser 
      power.
PG  - 74-80
LID - S1001-0742(18)32007-2 [pii]
LID - 10.1016/j.jes.2018.11.001 [doi]
AB  - We studied engine-out soot samples collected from a heavy-duty direct-injection 
      diesel engine and port-fuel injection gasoline spark-ignition engine. The two 
      types of soot samples were characterized using Raman spectroscopy with different 
      laser powers. A Matlab program using least-square-method with 
      trust-region-reflective algorithm was developed for curve fitting. A DOE (design 
      of experiments) method was used to avoid local convergence. The method was used 
      for two-band fitting and three-band fitting. The fitting results were used to 
      determine the intensity ratio of D (for "Defect" or "Disorder") and G (for 
      "Graphite") Raman bands. It is found that high laser power may cause oxidation of 
      soot sample, which gives higher D/G intensity ratio. Diesel soot has consistently 
      higher amorphous/graphitic carbon ratio, and thus higher oxidation reactivity, 
      compared to gasoline soot, which is reflected by the higher D/G intensity ratio 
      in Raman spectra measured under the same laser power.
CI  - Copyright (c) 2018. Published by Elsevier B.V.
FAU - Ge, Haiwen
AU  - Ge H
AD  - Department of Mechanical Engineering, Texas Tech University, Lubbock, TX 79409, 
      USA. Electronic address: haiwen.ge@ttu.edu.
FAU - Ye, Zhipeng
AU  - Ye Z
AD  - Department of Electrical and Computer Engineering, Texas Tech University, 
      Lubbock, TX 79409, USA.
FAU - He, Rui
AU  - He R
AD  - Department of Electrical and Computer Engineering, Texas Tech University, 
      Lubbock, TX 79409, USA. Electronic address: rui.he@ttu.edu.
LA  - eng
PT  - Journal Article
DEP - 20181114
PL  - Netherlands
TA  - J Environ Sci (China)
JT  - Journal of environmental sciences (China)
JID - 100967627
RN  - 0 (Gasoline)
RN  - 0 (Soot)
RN  - 0 (Vehicle Emissions)
SB  - IM
MH  - Gasoline
MH  - Lasers
MH  - Soot/*analysis
MH  - Spectrum Analysis, Raman
MH  - Vehicle Emissions/*analysis
OTO - NOTNLM
OT  - Diesel engine
OT  - Gasoline engine
OT  - Particulate matter
OT  - Raman spectroscopy
OT  - Soot emission
EDAT- 2019/02/21 06:00
MHDA- 2019/03/12 06:00
CRDT- 2019/02/21 06:00
PHST- 2018/07/23 00:00 [received]
PHST- 2018/10/26 00:00 [revised]
PHST- 2018/11/01 00:00 [accepted]
PHST- 2019/02/21 06:00 [entrez]
PHST- 2019/02/21 06:00 [pubmed]
PHST- 2019/03/12 06:00 [medline]
AID - S1001-0742(18)32007-2 [pii]
AID - 10.1016/j.jes.2018.11.001 [doi]
PST - ppublish
SO  - J Environ Sci (China). 2019 May;79:74-80. doi: 10.1016/j.jes.2018.11.001. Epub 
      2018 Nov 14.