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Tao Z.,Mu Danjiang Normal University
Advanced Materials Research | Year: 2012

Forest fire is one of the most important ecological factors in the forest ecosystem. The Daxinanling forest region has not only the largest forest areas, but also the biggest forest fire burned area in China. By analyzing the recorded climate and forest fire data of Ta He forestry bureau from 1974 to 2004, the following results can be concluded: (1) There were 298 forest fires recorded by Ta He forestry bureau during 31 years and the burned area were 1.63 million hectares totally with 9.6 forest fires per year, unpredictable and short fire cycle as characters. (2) According to the occurrence time of forest fires, the Julian date concentrated between 102∼181 and 240∼293, corresponding April 12th to June 30th and August 28th to October 20th, which were spring and autumn fire prevention periods. Major fires mainly occurred in spring of 1974∼1982, 1986∼1987, 1993, and 1998∼2002. The major fires cycle were 4 to 5 years. (3) The related indices of temperature, relative humidity, rainfall, and wind speed recorded in June in Ta He forestry bureau were 0.3929, 0.5274, 0.6136 and 0.1679. Temperature, relative humidity and rainfall factors in June had obvious linear relationships to forest fires, while the relationship between wind speed and forest fires is unobvious. Source


Zuo M.-H.,Mu Danjiang Normal University | Liu H.-L.,Jilin University | Huang X.-R.,Jilin University | Cui S.-X.,Mu Danjiang Normal University
Russian Journal of Physical Chemistry A | Year: 2012

The reaction of N( 4 S) radical with NO 2 molecule has been studied theoretically using density functional theory and ab initio quantum chemistry method. Both singlet and triplet electronic state [N 2O 2] potential energy surfaces (PESs) are calculated at the G3B3 level of theory. Also, the highly cost-expensive coupled-cluster theory including single and double excitations and perturbative inclusion of triple excitations CCSD(T)/cc-pVTZ single-point energy calculation is performed on the basis of the geometries obtained at the Becke's three parameter Lee-Yang-Parr B3LYP/6-311++G(d, p) level. On the singlet PES of the title reaction, it is shown that the most feasible pathway should be as follows. The atomic radical N attacking the NO bond of the NO 2 molecule first to form the adduct 1 N(NO)O, followed by one of the NO bond broken to give intermediate 2 ONNO, and then to the major products P1 (2NO). On the triplet PES of the title reaction, it is shown that the most favorable pathway should be the atomic radical N attacking the N-atom of NO 2 firstly to form the adduct 7 NN(OO), followed by one of the NO bonds breaking to give intermediate 8 NNOO, and then leading to the major products P2 (O 2 + N 2). As efficient routes to the reduction of NO 2 to form N 2 and O 2 are sought, both kinetic and thermodynamic considerations support the viability of this channel. All the involved transition states for generation of (2NO), ( 3O + N 2O), and (O 2 + N 2) lie much lower than the reactants. Thus, the novel reaction N + NO 2 can proceed effectively even at low temperatures and it is expected to play a role in both combustion and interstellar processes. The other reaction pathways are less competitive due to thermodynamical or kinetic factors. On the basis of the analysis of the kinetics of all path-ways through which the reactions proceed, we expect that the competitive power of reaction pathways may vary with experimental conditions for the title reaction. The calculated reaction heats of formation are in good agreement with that obtained experimentally. © 2012 Pleiades Publishing, Ltd. Source


Zhuang Z.,Mu Danjiang Normal University | Shi X.,Changchun University of Technology | Chen Y.,Mu Danjiang Normal University | Zuo M.,Mu Danjiang Normal University
Spectrochimica Acta - Part A: Molecular and Biomolecular Spectroscopy | Year: 2011

Surface-enhanced Raman spectra of trans-1,2-bis (4-pyridyl)-ethylene (t-BPE) on silver foil were detected at laser line of 514.5, 633, 785 and 1064 nm, respectively. The structure of Ag-t-BPE, Ag 4-t-BPE, Ag 6-t-BPE, Ag 10-t-BPE and Ag 20-t-BPE complexes has been calculated using a local version of the Amsterdam density functional program package. The Raman spectra and electronic polarizability of t-BPE-Ag at 514.5, 633, 785 and 1064 nm excitation lines were calculated. The Raman bands of t-BPE were assigned according to the calculation of potential energy distribution. The experimental and calculated Raman spectra of t-BPE-Ag at 514.5, 633, 785 and 1064 nm were compared. The relative Raman intensities change at different excitation lines were discussed based on the Raman enhanced mechanism and surface selection rules. © 2011 Elsevier B.V. All rights reserved. Source


Cui S.,Mu Danjiang Normal University | Zuo M.,Mu Danjiang Normal University | Zhang J.,Northeast Normal University | Zhao Y.,Northeast Normal University | Wang H.,Mu Danjiang Normal University
Acta Crystallographica Section E: Structure Reports Online | Year: 2012

The title compound, [Cu(NCS)(C 16H 12N 2)] n , was synthesised under hydro-thermal conditions. The Cu I ion shows distorted tetra-hedral geometry being coordinated by two N atoms from a 5-phenyl-2,2′-bipyridine ligand and by the N and S atoms from two different thio-cyanate anions. The Cu I ions are bridged by thio-cyanide groups, forming a one-dimensional coordination polymer along the b axis. The crystal packing is through van der Waals contacts and C - H⋯π inter-actions. Source


Cui S.,Mu Danjiang Normal University | Zuo M.,Mu Danjiang Normal University | Wang H.,Mu Danjiang Normal University | Xu J.,Mu Danjiang Normal University
Zeitschrift fur Anorganische und Allgemeine Chemie | Year: 2015

The complexes [Cu5(CN)5(5-ph-2,2′-bpy)3]n (1) and {Cu(SCN)(5-ph-2,2′-bpy)}n (2) were prepared by reaction of CuCl2 with different bridging ligands such as cyanide- or thiocyanate under hydrothermal conditions in the presence of 5-phenyl-2,2′-bipyridine (5-ph-2,2′-bpy). The copper ions are bridged by cyanide anions to form 1D ribbon with 26-membered {Cu10(CN)8} rings in complex 1, whereas the metal ions are bridged by thiocyanate anions to form a 1D chain in complex 2. Copyright © 2015 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim. Source

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