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Counter-Wind Deep Current in the Northern Beibu Gulf in Boreal Winter 被引量:2
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作者 GAO Jingsong WU Guidan +1 位作者 NGUYEN Kim-Cuong SHI Maochong 《Journal of Ocean University of China》 SCIE CAS CSCD 2019年第1期57-68,共12页
The Beibu Gulf is at an important geographical location and rich in gas, oil and biological resources. The observed currents showed that the current in the upper layer was opposite to that in the lower layer in boreal... The Beibu Gulf is at an important geographical location and rich in gas, oil and biological resources. The observed currents showed that the current in the upper layer was opposite to that in the lower layer in boreal winter in the northern Beibu Gulf and it was northeastward in the lower layer. This northeastward current was reproduced by a 3 D baroclinic model in this study. It's found that the counter-wind deep current(referred to as ‘CWDC' hereinafter) strengthened from September to November but weakened from December to the following February. A closed meridional circulation in vertical direction was found in the northern Beibu Gulf, including CWDC, surface southwestward current, an upwelling, and a downwelling. The temporal variation process of the meridional circulation was similar to that of CWDC, with strength and range stronger in November and December than in other four months. Similar to the variation process of CWDC, the monsoon wind changed from weak easterly wind in September to strong northeasterly wind in November and December, and it was transformed into weak southeasterly wind in February again. The sensitive experiments showed that CWDC and the meridional circulation were controlled by the monsoon wind and were adjusted by heat flux-and tide-induced mixing, respectively. According to the momentum balance equation, it can be revealed the counter-wind deep current is a compensation current which is induced by the surface elevation gradient balanced by the Coriolis force, vertical diffusion and baroclinic pressure gradient. 展开更多
关键词 Beibu GULF numerical model(POM) counter-wind DEEP current(CWDC) monsoon WIND momentum balance equation
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The summertime circulation of the Bohai Sea simulated from a high-resolution wave-tide-circulation coupled model 被引量:2
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作者 Changshui Xia Jingsong Guo +2 位作者 Guansuo Wang Zhenhua Chen Xiaodi Kuang 《Acta Oceanologica Sinica》 SCIE CAS CSCD 2019年第1期32-37,共6页
The Bohai Sea is a shallow semi-enclosed inner sea with an average depth of 18 m and is located at the west of the northern Yellow Sea. The climatological circulation pattern in summer of the Bohai Sea is studied by u... The Bohai Sea is a shallow semi-enclosed inner sea with an average depth of 18 m and is located at the west of the northern Yellow Sea. The climatological circulation pattern in summer of the Bohai Sea is studied by using a wave-tide-circulation coupled model. The simulated temperature and the circulation agree with the observation well. The result shows that the circulation pattern of the Bohai Sea is jointly influenced by the tidal residual current, wind and baroclinic current. There exists an obvious density current along the temperature front from the west part of the Liaodong Bay to the offshore area of the Huanghe Estuary. In the Liaodong Bay there exists a clockwise gyre in the area north to the 40°N. While in the area south to the 40°N the circulation shows a two-gyre structure, the flow from the offshore area of the Huanghe Estuary to the Liaodong Bay splits into two branches in the area between 39°N and 40°N. The west branch turns into north-west and forms an anti-clockwise gyre with the south-westward density current off the west of the Liaodong Bay. The east branch turns to the east and forms a clockwise gyre with the flow along the east coast of the Liaodong Bay. The forming mechanism of the circulation is also discussed in this paper. 展开更多
关键词 Bohai Sea summer CIRCULATION baroclinic current wave-tide-circulation coupled model
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Spatial-temporal Changes of Vegetation Cover in Guizhou Province, Southern China 被引量:23
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作者 TIAN Yichao BAI Xiaoyong +2 位作者 WANG Shijie QIN Luoyi LI Yue 《Chinese Geographical Science》 SCIE CSCD 2017年第1期25-38,共14页
Guizhou Province is an important karst area in the world and a fragile ecological area in China. Ecological risk assessment is very necessary to be conducted in this region. This study investigates different character... Guizhou Province is an important karst area in the world and a fragile ecological area in China. Ecological risk assessment is very necessary to be conducted in this region. This study investigates different characteristics of the spatial-temporal changes of vegetation cover in Guizhou Province of Southern China using the data set of SPOT VEGETATION(1999–2015) at spatial resolution of 1-km and temporal resolution of 10-day. The coefficient of variation, the Theil-Sen median trend analysis, and the Mann-Kendall test are used to investigate the spatial-temporal change of vegetation cover and its future trend. Results show that: 1) the spatial distribution pattern of vegetation cover in Guizhou Plateau is high in the east whereas low in the west. The average annual normalized difference vegetation index(NDVI) from west to east is higher than that from south to north. 2) Average annual NDVI improved obviously in the past 17 years. The growth rate of average annual NDVI is 0.028/10 yr, which is slower than that of vegetation in the country(0.048/10 yr) from 1998 to 2007. Average annual NDVI in karst area is lower than that in non-karst area. However, the growing rate of average annual NDVI in karst area(0.030/10 yr) is faster than that in non-karst area(0.023/10 yr), indicating that vegetation coverage increases more rapidly in karst area. 3) Vegetation coverage in the study area is stable overall, but fluctuates in the local scales. 4) Vegetation coverage presents a continuous increasing trend. The Hurst exponent of NDVI in different vegetation types has an obvious threshold in various elevations. 5) The proportion of vegetation cover with sustainable increase is higher than that of vegetation cover with sustainable decrease. The improvement in vegetation cover may expand to most parts of the study area. 展开更多
关键词 vegetation cover spatial-temporal change trends analysis normalized difference vegetation index(NDVI) Hurst exponent Guizhou Province China
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Records of bulk organic matter and plant pigments in sediment of the "red-tide zone" adjacent to the Changjiang River estuary 被引量:2
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作者 亢振军 于仁成 +5 位作者 孔凡洲 王云峰 高岩 陈建华 郭伟 周名江 《Chinese Journal of Oceanology and Limnology》 SCIE CAS CSCD 2016年第5期915-927,共13页
Cultural eutrophication caused by nutrient over-enrichment in coastal waters will lead to a cascading set of ecosystem changes and deleterious ecological consequences,such as harmful algal blooms(HABs) and hypoxia.Dur... Cultural eutrophication caused by nutrient over-enrichment in coastal waters will lead to a cascading set of ecosystem changes and deleterious ecological consequences,such as harmful algal blooms(HABs) and hypoxia.During the past two decades since the late 1990s,recurrent large-scale HABs(red tides)and an extensive hypoxic zone have been reported in the coastal waters adjacent to the Changjiang River estuary.To retrieve the history of eutrophication and its associated ecosystem changes,a sediment core was collected from the "red-tide zone" adjacent to the Changjiang River estuary.The core was dated using the^(210)Pb radioisotope and examined for multiple proxies,including organic carbon(OC),total nitrogen(TN),stable isotopes of C and N,and plant pigments.An apparent up-core increase of OC content was observed after the 1970s,accompanied by a rapid increase of TN.The concurrent enrichment of δ^(13)C and increase of the C/N ratio suggested the accumulation of organic matter derived from marine primary production during this stage.The accumulation of OC after the 1970 s well reflected the significant increase of primary production in the red-tide zone and probably the intensification of hypoxia as well.Plant pigments,including chlorophyll a,p-carotene,and diatoxanthin,showed similar patterns of variation to OC throughout the core,which further confirmed the important contribution of microalgae,particularly diatoms,to the deposited organic matter.Based on the variant profiles of the pigments representative of different microalgal groups,the potential changes of the phytoplankton community since the 1970s were discussed. 展开更多
关键词 EUTROPHICATION harmful algal bloom HYPOXIA PIGMENT sediment core Changjiang River estuary
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Comparison of Nutritional Quality in Fish Maw Product of Croaker Protonibea diacanthus and Perch Lates niloticus 被引量:8
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作者 WEN Jing ZENG Ling +1 位作者 Chen Ziming XU Youhou 《Journal of Ocean University of China》 SCIE CAS 2016年第4期726-730,共5页
Fish maw(the dried swimbladders of fish) is ranked in the list of the four sea treasures in Chinese cuisine. Fish maw is mainly produced from croaker, which is the most highly priced. However, some of the fish maw bei... Fish maw(the dried swimbladders of fish) is ranked in the list of the four sea treasures in Chinese cuisine. Fish maw is mainly produced from croaker, which is the most highly priced. However, some of the fish maw being sold as croaker maw are in fact not from croaker, but from the Nile perch Lates niloticus. The present work determined and compared the proximate composition, amino acid and fatty acid composition of croaker Protonibea diacanthus maw and perch L. niloticus maw. The results indicated that both maws were high protein sources and low in fat content. The dominant amino acids in both maws were glycine, proline, glutamic acid, alanine and arginine. These amino acids constituted 66.2% and 66.4% of the total amino acids in P. diacanthus and L. niloticus, respectively. The ratio of FAA: TAA(functional amino acids: total amino acids) in both maws were 0.69. This is a good explanation for why fish maws have been widely utilized as a traditional tonic and remedy in Asia. Except valine and histidine, all the essential amino acid contents in P. diacanthus were higher than in L. niloticus. Moreover, croaker P. diacanthus maw contained more AA and DHA than perch L. niloticus maw, showing a higher ratio of n-3 / n-6, which is more desirable. 展开更多
关键词 perch Lates proline proximate arginine histidine explanation remedy contained tonic
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Influence of nanoparticle concentrations on flow boiling heat transfer coefficients of Al_2O_3/R141b in micro heat exchanger by direct metal laser sintering 被引量:4
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作者 Jianyang Zhou Xiaoping Luo +4 位作者 Cong Deng Mingyu Xie Lin Zhang Di Wu Feng Guo 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2017年第12期1714-1726,共13页
Al2O3/R141b + Span-80 nanorefrigerant for 0.05 wt.% to 0.4 wt.% is prepared by ultrasonic vibration to investigate the influence of nanoparticle concentrations on flow boiling heat transfer of Al2O3/R141b + Span-80... Al2O3/R141b + Span-80 nanorefrigerant for 0.05 wt.% to 0.4 wt.% is prepared by ultrasonic vibration to investigate the influence of nanoparticle concentrations on flow boiling heat transfer of Al2O3/R141b + Span-80 in micro heat exchanger by direct metal laser sintering. Experimental results show that nanoparticle concentrations have significantly impact on heat transfer coefficients by homogeneity test of variances according to mathematical statistics. The heat transfer performance of Al2O3/R141b + Span-80 nanorefrigerant is enhanced after adding nanoparticles in the pure refrigerant R141b. The heat transfer coefficients of 0.05 wt.%, 0.1 wt.%, 0.2 wt.%, 0.3 wt.% and 0.4 wt.% Al2O3/R141 b + Span-80 nanorefrigerant respectively increase by 55.0% 72.0%, 53.0% 42.3% and 39.9% compared with the pure refrigerant R141b. The particle fluxes from viscosity gradient, non-uniform shear rate and Brownian motion cause particles to migrate in fluid especially in the process of flow boiling. This migration motion enhances heat transfer between nanoparticles and fluid. Therefore, the heat transfer performance of nanofluid is enhanced. It is important to note that the heat transfer coefficients nonlinearly increase with nanoparticle concentrations increasing. The heat transfer coefficients reach its maximum value at the mass concentration of 0.1% and then it decreases slightly. There exists an optimal mass concentration corresponding to the best heat transfer enhancement. The reason for the above phenomenon is attributed to nanoparticles deposition on the minichannel wall by Scanning Electron Microscopy observation. The channel surface wettability increases during the flow boiling experiment in the mass concentration range from 0.2 wt.% to 0.4 wt.%. The channel surface with wettability increasing needs more energy to produce a bubble. Therefore, the heat transfer coefficients decrease with nanopartide concentrations in the range from 0.2 wt.% to 0.4 wt.%. In addition, a new correlation has been proposed by fitting the experimental data considering the influence of mass concentrations on the heat trans- fer performance. The new correlation can effectively predict the heat transfer coefficient. 展开更多
关键词 Nanoparticle Concentration Minichannel Sintering Flow boiling Heat transfer coefficient
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Lipid Oxidation and Fatty Acid Composition in Salt-Dried Yellow Croaker(Pseudosciaena polyactis) During Processing 被引量:5
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作者 CAI Qiuxing WU Yanyan +3 位作者 LI Laihao WANG Yueqi YANG Xianqing ZHAO Yongqiang 《Journal of Ocean University of China》 SCIE CAS CSCD 2017年第5期855-862,共8页
Lipid oxidation in salt-dried yellow croaker(Pseudosciaena polyactis) was evaluated during processing with commonly used analytical indices, such as the peroxide value(POV), the thiobarbituric acid reactive substances... Lipid oxidation in salt-dried yellow croaker(Pseudosciaena polyactis) was evaluated during processing with commonly used analytical indices, such as the peroxide value(POV), the thiobarbituric acid reactive substances(TBARS) value, and oxidative-relative lipoxygenase(LOX) activity. Additionally, fatty acids were analyzed using gas chromatography-mass spectrometry. Both POV and TBARS increased significantly(P < 0.05) at the rinsing stage. POV reached its peak value of 3.63 meq O_2 per kg sample at the drying stage, whereas TBARS constantly increased from 0.05 to 0.20 mg MDA per kg sample. Processing of salt-dried yellow croaker had an extremely significant(P < 0.01) effect on LOX activity. Twenty-six fatty acids were identified. Combined eicosapentaenoic acid(EPA; C20:5n3) and docosahexaenoic acid(DHA; C22:6n3) content varied between(19.20 ±0.37) mg g^(-1) and(23.45 ± 1.05) mg g^(-1). The polyunsaturated fatty acid/saturated fatty acid(PUFA/SFA) ratio in yellow croaker was 0.73–1.10, and the n-6/n-3 PUFA ratio was approximately 0.13–0.20. The contents of most fatty acids varied significantly(P <0.05) during the different processing stages, and these differences were caused by lipid oxidation. C18:0, C16:1n7, C19:0, and C22:6n3 showed clear changes in principle component one of a principle components analysis. These fatty acids are potential markers for evaluating lipid oxidation in fish muscle because there was a significant correlation between these markers and TBARS and LOX activity(P < 0.05) with Pearson's coefficients > 0.931. 展开更多
关键词 Pseudosciaena yellow PUFA Lipid constantly varied saturated dried lipoxygenase extremely
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Synthesis,Structure,and Surface Photo-electric Properties of a New Zn(Ⅱ)Coordination Complex Constructed from 2-(1H-benzotriazol-1-yl)acetic Acid and 1,10-Phenanthroline Ligands 被引量:2
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作者 李家明 史忠丰 何坤欢 《Chinese Journal of Structural Chemistry》 SCIE CAS CSCD 2016年第1期135-142,共8页
A new binuclear Zn^Ⅱ coordination complex,Zn2(bta)(phen)2(Cl)3(1,Hbta = 2-(1Hbenzotriazol-1-yl)acetic acid and phen = 1,10-phenanthroline),has been synthesized and characterized by single-crystal X-ray diff... A new binuclear Zn^Ⅱ coordination complex,Zn2(bta)(phen)2(Cl)3(1,Hbta = 2-(1Hbenzotriazol-1-yl)acetic acid and phen = 1,10-phenanthroline),has been synthesized and characterized by single-crystal X-ray diffraction,IR spectroscopy,elemental,and photoluminescent analysis.Complex 1 crystallizes in triclinic system,space group P1 with a = 9.3040(19),b = 10.694(2),c =16.841(3) A°,α = 101.18(3),β = 105.77(3),γ = 91.72(3)°,V= 1575.8(5) A°3,C(32)H(22)Zn2Cl3N7O2,Mr =773.66,Dc = 1.631 g/cm^3,Z = 2,F(000) = 780,μ = 1.820 mm^-1,the final R = 0.1238 and wR =0.1131.X-ray diffraction analyses indicate that 1 displays two crystallographic independent Zn^Ⅱmetal centers with a distorted tetragonal pyramidal(ZnN4O) and a tetrahedral(ZnNCl3) geometries,respectively.The phen serves as a common N,N'-bidentate ligand,and the bta^- as a unique N,O-bridged ligand in 1.In the crystal,1 forms a stable 3D supramolecular architecture by trifurcated hydrogen bonding C-H…C1 interactions and C-H…π,π…π stacking.1 showed photo-electric conversion properties. 展开更多
关键词 photo-electric property zinc(Ⅱ) complex 2-(1H-benzotriazol-1-yl)acetic acid synthesis crystal structure
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Synthesis and Crystal Structure of a New 2D O-bridged Copper(Ⅱ) Coordination Polymer Constructed from Sulfonate-derived Schiff Base 被引量:1
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作者 欧阳淼 李家明 +3 位作者 蒋毅民 刘旭辉 张晖英 廖蓓玲 《Chinese Journal of Structural Chemistry》 SCIE CAS CSCD 2015年第2期299-305,共7页
A new chain-like coordination polymer, namely, [CuL]n (1, Na2L = 2-[(2-hydroxy- benzylidene)-amino]-benzenesulfonic acid sodium salt), has been synthesized and characterized by single-crystal X-ray diffraction, IR... A new chain-like coordination polymer, namely, [CuL]n (1, Na2L = 2-[(2-hydroxy- benzylidene)-amino]-benzenesulfonic acid sodium salt), has been synthesized and characterized by single-crystal X-ray diffraction, IR spectroscopy and elemental analysis. Complex 1 crystallizes in monoclinic system, space group P21/c with a = 9.2296(16), b = 10.4754(18), c = 12.200(2) A, β = 102.392(2)°, V = 1152.0(3)A3, CI3H9CuNOaN, Mr = 338.83, Dc = 1.953 g/cm3, Z = 4, F(000) = 684, p = 2.089 mm-1, the final R = 0.0376 and wR = 0.0956. X-ray diffraction analyses indicate that 1 displays a square-pyramidal metal center with NO4 donor sets. The sulfonate-derived Schiff base serves as a common N,O,O'-tridentate and a unique O-bridged ligand connecting the metals. Dinuclear copper complexes serve as secondary building blocks (SBUs) to construct an unusual 2D coordination network. In the crystal, the components form a stable 3D supramolecular architecture by C-H...O interactions and to-stacking 展开更多
关键词 sulfonate-derived Schiff base copper(II) complex synthesis crystal structure
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Interaction between Breathers and Rogue Waves in a Nonlinear Optical Fiber 被引量:2
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作者 Xiang-Shu Liu Li-Chen Zhao +3 位作者 Liang Duan Peng Gao Zhan-Ying Yang Wen-Li Yang 《Chinese Physics Letters》 SCIE CAS CSCD 2018年第2期1-5,共5页
We study the interaction between breather and N-order rogue waves in a nonlinear optical fiber.The impacts of the relative phase and the interaction distance between breathers and rogue waves are discussed in detail.S... We study the interaction between breather and N-order rogue waves in a nonlinear optical fiber.The impacts of the relative phase and the interaction distance between breathers and rogue waves are discussed in detail.Specifically,the breather can reduce the maximum hump value of high-order rogue waves greatly in the eases of nonzero relative phase or nonzero interaction distance.The characteristic of exclusion between breathers and rogue waves is described qualitatively in the situation of different interaction distances,which can be used to change the temporal-spatial distribution of rogue waves.Their interaction properties are characterized by the trajectory of localized waves'valleys and humps.It is shown that the interaction changes the dynamical evolution trajectory of rogue waves and breathers.These results provide some possible ways to control high-order rogue waves. 展开更多
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A MULTIDIMENSIONAL CENTRAL LIMIT THEOREM WITH SPEED OF CONVERGENCE FOR AXIOM A DIFFEOMORPHISMS
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作者 夏红强 檀大耀 《Acta Mathematica Scientia》 SCIE CSCD 2011年第3期1123-1132,共10页
Let T:X → X be an Axiom A diffeomorphism,m the Gibbs state for a Hlder continuous function ɡ. Assume that f:X → R^d is a Hlder continuous function with ∫_X^(fdm) = 0.If the components of f are cohomologously i... Let T:X → X be an Axiom A diffeomorphism,m the Gibbs state for a Hlder continuous function ɡ. Assume that f:X → R^d is a Hlder continuous function with ∫_X^(fdm) = 0.If the components of f are cohomologously independent, then there exists a positive definite symmetric matrix σ~2:=σ~2 (f ) such that S^fn √ n converges in distribution with respect to m to a Gaussian random variable with expectation 0 and covariance matrix σ~2 . Moreover, there exists a real number A 〉 0 such that, for any integer n ≥ 1,Π( m*( 1√ nS f n ),N (0,σ~2 ) ≤A√n, where m*(1√ n S^fn)denotes the distribution of 1√ n S^fn with respect to m, and Π is the Prokhorov metric. 展开更多
关键词 multidimensional central limit theorem Axiom A diffeomorphisms symbolic dynamics transfer operator
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Process Optimization of Extraction Technique of Polysaccharide from Leaves of Dendrobium officinale
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作者 Yunying ZHENG Yanzhen YIN +1 位作者 Shuming ZHONG Ruirui ZHANG 《Medicinal Plant》 CAS 2018年第5期27-30,35,共5页
[Objectives] To optimize the extraction process of polysaccharides from leaves of Dendrobium officinale. [Methods]The polysaccharides from D. officinale were extracted by internal boiling method. The extraction rate o... [Objectives] To optimize the extraction process of polysaccharides from leaves of Dendrobium officinale. [Methods]The polysaccharides from D. officinale were extracted by internal boiling method. The extraction rate of polysaccharides from D. officinale was studied.Based on the single factor experiment,the L_9( 3~3) orthogonal experiment was designed to optimize the extraction process of polysaccharides from D. officinale. [Results]The optimum process for extracting polysaccharides from D. officinale by internal boiling method was as follows:1. 00 g of D. officinale powder was desorbed with 6. 0 mL of 20% ethanol for 20 min,35. 0 mL of 90℃ water was rapidly added,and the extraction time was 5 min. [Conclusions] Under this condition,the extraction rate of polysaccharides from D. officinale was 12. 31%,which was 3. 75 percentage points higher than that of traditional reflux extraction. 展开更多
关键词 LEAVES of DENDROBIUM officinale INTERNAL BOILING method POLYSACCHARIDES Extraction
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Synthesis and Crystal Structure of a Cadmium(Ⅱ) Coordination Polymer:[Cd_2Cl_4(bpme)]_n·n(2H_2O)
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作者 李超柱 黄学仁 +2 位作者 陈艳辉 李家明 蒋毅民 《Chinese Journal of Structural Chemistry》 SCIE CAS CSCD 2011年第5期644-647,共4页
A novel coordination polymer, [Cd2Cl4(bpme)]n·n(H2O) (1, bpme=2,5-bis(be-nzoimidazol-2-yl)pyrazine), has been synthesized and its crystal structure was determined by single-crystal X-ray diffraction. The ... A novel coordination polymer, [Cd2Cl4(bpme)]n·n(H2O) (1, bpme=2,5-bis(be-nzoimidazol-2-yl)pyrazine), has been synthesized and its crystal structure was determined by single-crystal X-ray diffraction. The crystal of the complex belongs to the triclinic system, space group P , with a=7.0737(9), b=8.7886(11), c=9.4561(12) , α=105.3580(10), β=94.981(2), γ=96.879(2)°, V=558.46(12) 3, Mr=714.97, Z=1, F(000)=346, Dc=2.126 g/cm3, μ=2.412 mm-1, T=296(2) K, S=1.057, R=0.0533 and wR=0.1480. According to the structural analysis, the Cd(Ⅱ) ion adopts a slightly distorted six-coordinated octahedral geometry. The Cd(Ⅱ) atoms are bridged by four Cl atoms along the a direction, forming infinite straight chains which are further constructed to generate 2D network layer structures through the μ4-N bpme ligand in the b direction, and such 2D network layer structures finally form a novel three-dimensional infinite supramolecular framework through weak π-π stacking between two network layers and hydrogen bonds. 展开更多
关键词 coordination polymer Cd(Ⅱ) complex 2 5-bis(benzoimidazol-2-yl)pyrazine crystal structure
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Total Maximum Allocated Loads on Stoichiometry of Nitrogen and Identification of Critical Form in Jiaozhou Bay, China
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作者 LIN Guohong SONG Xianli +3 位作者 LU Dongliang LI Keqiang LIANG Shengkang WANG Xiulin 《Journal of Ocean University of China》 SCIE CAS CSCD 2020年第3期622-632,共11页
Total pollutant load control management for total dissolved nitrogen(TDN) is an urgent task required to gain a good water quality status in Jiaozhou Bay(JZB), China. In this paper, the stoichiometry of multiform TDN o... Total pollutant load control management for total dissolved nitrogen(TDN) is an urgent task required to gain a good water quality status in Jiaozhou Bay(JZB), China. In this paper, the stoichiometry of multiform TDN on land-ocean interactions associated with marine biogeochemical reaction(LOIMBR) was studied by modeling the load-response relationship based on a three-dimensional water quality model of nitrogen in JZB. The results showed that the stoichiometry on LOIMBR of dissolved organic nitrogen(DON), NO3-N and NH4-N was 3:1:1, with one-third of the contribution on the concentration of dissolved inorganic nitrogen(DIN) in JZB for the land-based DON loads to DIN loads. Based on the stoichiometric relationship of nitrogen forms, the total maximum allocated load(TMAL) of equivalent TDN(ETDN) was approximately 5300 t a^-1 in JZB, equivalent to the TMAL of 5700, 5800 and 15600 t a^-1 for NH4-N, NO3-N and DON, respectively. According to the loads of ETDN, there were four outfalls overloaded in JZB in 2015, which lie in the head of the bay. In the four overloaded outfalls, besides NO3-N, NH4-N was the critical nitrogen control form for Moshui River, while DON for Dagu River and Haibo River. The results of numerical experiments further showed that JZB will achieve good water quality after 7 years by implementation of the 'different emission reduction' based on TMAL of ETDN, which is significantly better than 'equal percent removal'. 展开更多
关键词 total dissolved nitrogen water quality STOICHIOMETRY total maximum allocated load Jiaozhou Bay
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Asymmetric W-shaped and M-shaped soliton pulse generated from a weak modulation in an exponential dispersion decreasing fiber
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作者 刘祥树 赵立臣 +2 位作者 段亮 杨战营 杨文力 《Chinese Physics B》 SCIE EI CAS CSCD 2017年第12期139-145,共7页
We study localized waves on continuous wave background in an exponential dispersion decreasing fiber with two orthogonal polarization states. We demonstrate that asymmetric W-shaped and M-shaped soliton pulse can be g... We study localized waves on continuous wave background in an exponential dispersion decreasing fiber with two orthogonal polarization states. We demonstrate that asymmetric W-shaped and M-shaped soliton pulse can be generated from a weak modulation on continuous wave background. The numerical simulation results indicate that the generated asymmetric soliton pulses are robust against small noise or perturbation. In particular, the asymmetric degree of the asymmetric soliton pulse can be effectively controlled by changing the relative frequency of the two components. This character can be used to generate other nonlinear localized waves, such as dark-antidark and antidark-dark soliton pulse pair, symmetric W-shaped and M-shaped soliton pulse. Furthermore, we find that the asymmetric soliton pulse possesses an asymmetric discontinuous spectrum. 展开更多
关键词 asymmetric soliton pulse asymmetric discontinuous spectrum exponential dispersion decreasing fiber
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Hydrothermal Synthesis, Crystal Structure and Surface Photo-electric Properties of a New Nickel(Ⅱ) 3-D Metalorganic Framework Constructed from the Rigid 1,4-Bis(imidazol-1-yl) benzene Ligand
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作者 王爱荣 李家明 +2 位作者 史忠丰 何坤欢 高健 《Chinese Journal of Structural Chemistry》 SCIE CAS CSCD 2017年第4期647-653,共7页
A new 3-D nickel(Ⅱ) metal-organic framework(MOFs) with formula [Ni(bib)_2(SO_4)]_n(1), where bib = 1,4-bis(imidazol-1-yl)benzene, has been synthesized and characterized by single-crystal X-ray diffraction... A new 3-D nickel(Ⅱ) metal-organic framework(MOFs) with formula [Ni(bib)_2(SO_4)]_n(1), where bib = 1,4-bis(imidazol-1-yl)benzene, has been synthesized and characterized by single-crystal X-ray diffraction, IR spectroscopy, elemental analysis and surface photovoltage spectroscopy(SPS). Complex 1 crystallizes in monoclinic system, space group C2/c with a = 19.5988(6), b = 9.7531(3), c = 11.8146(4) ?, β = 96.185(3)°, V = 2245.20(12) ?~3, C_(24)H_(20)N_8NiO_4S, M_r = 575.25, D_c = 1.702 g/cm^3, Z = 4, F(000) = 1184, μ = 1.011 mm-1, the final R = 0.0293 and w R = 0.0702. X-ray diffraction analyses indicated that the center Ni^(2+) ion is six-coordinated with an O_2N_4 donor set of two μ_2-SO_4^(2–) and four bib ligands, resulting in an ideal octahedral geometry. Topological analysis on complex 1 considers each Ni^(2+) as a 6-connected node, while bib and sulfate ion as linkers, giving an α-Po topology with short Schl?fli symbol 412·63. In the crystal packing, the components interact with pairs of intermolecular C–H×××O hydrogen bonds. The SPS of 1 indicates that there are positive response bands in the range of 300~600 nm showing photo-electric conversion properties. 展开更多
关键词 photo-electric property nickel(Ⅱ) complex 1 4-bis(imidazol-1-yl)benzene synthesis crystal structure
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The Excavation and Practical Significance of Folk Art Education Resources of Ethnic Minorities in Guangxi of china
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作者 Zongting Bi 《Journal of Educational Theory and Management》 2017年第1期85-87,共3页
Guangxi minority folk art education resources is a valuable treasure trove of art, realistic significance to mining and utilization of Guangxi minority folk art education resources. The practice proves that Guangxi mi... Guangxi minority folk art education resources is a valuable treasure trove of art, realistic significance to mining and utilization of Guangxi minority folk art education resources. The practice proves that Guangxi minority folk art education resource is a typical folk art "Encyclopedia", is a folk song "epic" glorious and resplendent that is a piece of precious folk art "living fossil". Guangxi minority folk art education resources mining and utilization, enrich the arts and culture in Guangxi, China the students' national consciousness, and show the rich geographical and cultural characteristics. 展开更多
关键词 GUANGXI MINORITY Art education RESOURCES Mining and UTILIZATION SIGNIFICANCE
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The System Design of Green Wastewater Treatment in Campus Life
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作者 HOU Zhao-wu 《Meteorological and Environmental Research》 2012年第6期33-35,44,共4页
[Objective] The aim was to address the difficulty of long pipe for centralized sewage treatment in campus life and difficulty in use. [ Method] Though the four integrated approach of fermentation tank, coal ash slag f... [Objective] The aim was to address the difficulty of long pipe for centralized sewage treatment in campus life and difficulty in use. [ Method] Though the four integrated approach of fermentation tank, coal ash slag filters, chemical and biological membrane reactor and separation of heavy metals in electromagnetic fields, the green wastewater treatment system in campus life was designed to realize the recycle use of sewage in campus life. [ Result] The processed sewage can flush the restroom. The sludge in the processed sewage can feed earthworms, while earth- worms (material or production servers) were food for chickens and ducks and the compost of earthworms was fertilizer, which brought promising economic and social benefits. Tests showed that using the green treatment system to process campus sewage can achieve or pass national second emission standard. Process charge was 50% lower than the centralized sewage processed company and the treatment process was completely qreenized and recvclincl rate was hiah. 展开更多
关键词 SEWAGE WETLANDS Biological membrane reactor EARTHWORM China
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The impact of thinking differences between English and Chinese on translation
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作者 Jitao SI 《International Journal of Technology Management》 2014年第7期132-134,共3页
Translation is not only a language activity, but also a thinking activity, which involves the conversion of the two languages, and the language is both a thinking tool and the result of thinking. Language and thought ... Translation is not only a language activity, but also a thinking activity, which involves the conversion of the two languages, and the language is both a thinking tool and the result of thinking. Language and thought are closely related, and they are both interacting and interdependent. Different thinking determines that the expression of both English and Chinese on the same topic is also different. Through the relationship between language and thought, standing on a higher philosophical point of thinking, we can investigate the effect of the differences between English and Chinese translation. The translator can pay more attention to the difference' s impact of translation, which assure a higher accuracy of the translation. 展开更多
关键词 ENGLISH CHINESE thinking differences English translation
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LSSVM Combined with SPA Applied to Near-Infrared Quantitative Determination of the Octane in Fuel Petrol Samples
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作者 Lili Xu Jie Gu +2 位作者 Huazhou Chen Jiangbei Wen Gaili Xu 《Open Journal of Applied Sciences》 2018年第9期422-430,共9页
Least square support vector machine (LSSVM) combined with successive projection algorithm (SPA) method was applied for?near-infrared (NIR)?quantitative determination of the octane number in fuel petrol. The NIR spectr... Least square support vector machine (LSSVM) combined with successive projection algorithm (SPA) method was applied for?near-infrared (NIR)?quantitative determination of the octane number in fuel petrol. The NIR spectra of 87 fuel petrol samples were?scanned?for model establishment and optimization. First order derivative Savitzky-Golay smoother?(1st-d’SG) was?utilized to improve the?NIR predictive ability. Its pretreatment effect was compared with the raw data.?SPA was?applied for the extraction of informative wavelengths. Considering the linear and non-linear?training mechanism,?LSSVM?regression was employed to establish calibration models.?The correlation coefficient (R) and root mean square error (RMSE) were used as the model evaluation indices;accordingly the octane number in fuel petrol?was quantitatively determined with the prospective predictive indices. Results showed that?after pretreated by 1st-d’SG, 8 SPA-selected wavelengths?was generated as the inputs of LSSVM, so that the calibration models were optimized in the way of combining the SPA-LSSVM regression with the SG smoother.?The prediction results were quite satisfactory, with the calibrating correlation coefficient of?0.951 and the RMSE?of 3.282. An independent?testing?sample set was used to evaluate the optimal model, the testing?correlation coefficient?was 0.903 and the RMSE was 4.128. We conclude that?NIR spectrometry is feasible to determine the octane in fuel petrol?by establishing SPA-LSSVM?models. The 1st-d’SG pretreatment has?the?advantage of selecting wavelengths containing the implicit information. The combination of 1st-d’SG pretreatment and SPA-LSSVM show its applicable potential to predict the?octane number?in?fuel petrol. 展开更多
关键词 NEAR-INFRARED FUEL PETROL The OCTANE Number SPA LSSVM
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