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Simultaneous quantification of greenhouse gas and nitric oxide emissions from subtropical conventional vegetable systems:a 2-site field case study in Sichuan Basin

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Journal of Mountain Science 2021年第3期18卷 671-682页

作者： ZHang Bo-wen ZHOU ming-hua ZHU Bo Key Laboratory of Mountain Surface Processes and Ecological Regulation Institute of Mountain Hazards and EnvironmentChinese Academy of SciencesChengdu 610041China University of Chinese Academy of Sciences Beijing 100049China

Quantification of greenhouse gases[nitrous oxide(N_(2)O)and methane(CH_(4))]and nitric oxide(NO)emissions from subtropical conventional vegetable systems through multi-site field measurements are needed to obtain accurate regional and global estimates.N2 O,NO and CH4 emissions from subtropical conventional vegetable systems were simultaneously measured at two different sites with hilly topography in the Sichuan basin,southwest China by using the static chamber gas chromatography *** showed that annual soil N_(2)O and NO fluxes for the treatment receiving N fertilizer ranged from 6.34-7.71 kg N ha^(-1) yr^(-1) and 0.69-0.85 kg N ha^(-1) yr^(-1),respectively,while decreased soil CH4 uptakes by 26.4%as compared with no N fertilizer addition across our two sites of ***,the average direct N2 O and NO emission factor(EFd)were 0.71%and 0.12%,respectively,which were both lower than the available EFd for subtropical conventional vegetable *** finding indicates that current regional and global estimates of N_(2)O and NO emissions from vegetable fields are likely *** N_(2)O emissions(3.42-3.62 kg N ha^(-1) yr^(-1))from the subtropical conventional vegetable systems were relatively high as compared with available field measurements worldwide,suggesting that background N_(2)O emissions cannot be ignored for regional estimate of N_(2)O emissions in subtropical ***,the significantly intra-and inter-annual variations in N_(2)O,CH_(4) and NO emissions were also observed in the present study,which could be explained by temporal variations of environmental variables(*** temperature and moisture).The differences in N_(2)O and NO EFd and CH_(4)emissions between various vegetable systems in particular under subtropical conditions should be taken into account when compiling regional or global inventories and proposing mitigation practices.

关键词： Subtropical vegetable system Nitrous oxide Nitric oxide Methane Emission factor Background emissions

Methane and Nitrous Oxide Emissions from Rice-Duck and Rice-Fish Complex Ecosystems and the Evaluation of Their Economic Significance

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Agricultural Sciences in China 2009年第10期8卷 1246-1255页

作者： YUAN Wei-ling CAO Cou-gui LI Cheng-fang ZhaN ming CAI ming-li Wang Jin-ping Crop Physiology and Production Center （CPPC） Huazhong Agricultural University~Key Laboratory of Huazhong Crop PhysiologyEcology and Production Ministry of Agriculture Wuhan 430070 P.R China

Rice-duck （RD） and rice-fish （RF） ecological systems are major complex planting and breeding models of rice paddy fields in southern China. Studying the methane （CH4） and nitrous oxide （N2O） emissions and their economic value from these two ecosystems can provide theoretical and practical basis for further development and utilization of these classical agricultural techniques. CH4 and N2O emissions from RD and RF ecological systems were measured in situ by using static chambers technique. Using global warming potentials （GWPs）, we assessed the greenhouse effect of CH4 and N2O and their economic value. Results showed that the peaks of CH4 emission fluxes from RD and RF appeared at full tillering stage and at heading stage, and the average emission fluxes were significantly （P〈 0.05） lower than that from CK. N2O fluxes remained low when the field is flooded and high after draining the water. Compared with CK, the total amount of N2O emissions was significantly （P〈0.05） higher and slightly lower than those from RD and RF, respectively. In 2006 and 2007, the total greenhouse effect of CH4 and N20 from RD and RF were 4 728.3 and 4 611 kg CO2 ha^-1, 4 545 and 4 754.3 kg CO2 ha^-1, respectively. The costs of greenhouse effect were 970.89 and 946.81 RMB yuan ha^-1, and 933.25 and 976.23 RMB yuan ha^-1, respectively, which were significant lower than those from CK （5 997.6 and 5 391.5 RMB yuan ha^-1）. Except for the environment cost of CH4 and N2O, the economic benefits from RD and RF were 2 210.64 and 4 881.92 RMB yuan ha^-1; 3 798.37 and 5 310.64 RMB yuan ha^-1, respectively, higher than those from CK. Therefore, RD and RF complex ecological planting and breeding models can effectively decrease and control CH4 and N2O emissions, and they are two of the effective strategies to reduce greenhouse gases from rice paddy fields and contribute in alleviating global warming. Thus, their adoption is important to the environment together with their economy benefits.

关键词： methane emission nitrous oxide emission rice-duck complex ecosystem rice-fish complex ecosystem,greenhouse effect economic benefit

1,8-萘酰亚胺类衍生物的结构及紫外-可见吸收光谱

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物理化学学报 2009年第6期25卷 1143-1148页

作者：齐齐孙岳明哈涌泉东南大学化学化工学院南京211189

用密度泛函方法(DFT)优化了一系列1,8-萘酰亚胺衍生物,用含时密度泛函(TDDFT)和导体极化连续模型(CPCM)计算了它们在气相、环己烷和二氯甲烷溶剂条件下的紫外可见吸收光谱.计算结果表明,优化的几何结构和X射线晶体结构数据吻合较好.萘环... 详细信息

用密度泛函方法(DFT)优化了一系列1,8-萘酰亚胺衍生物,用含时密度泛函(TDDFT)和导体极化连续模型(CPCM)计算了它们在气相、环己烷和二氯甲烷溶剂条件下的紫外可见吸收光谱.计算结果表明,优化的几何结构和X射线晶体结构数据吻合较好.萘环4和5位胺基上取代基团(氢基、甲基、苯基和萘基)的变化使得它与萘酰亚胺部分的连接键长(N—C)变长、电荷转移增强、带隙降低.溶剂化显色效应和前线轨道电子云一致表明此类物质的最大吸收峰对应π-π*跃迁.异构体A中的分子内电荷转移增大和带隙的降低是它的紫外吸收光谱最大吸收峰比异构体B的发生红移的主要原因.

关键词： 1,8-萘酰亚胺衍生物密度泛函理论吸收光谱

Influence of Organic Amendments on Adsorption, Desorption and Leaching of Methiopyrisulfuron in Soils

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Journal of Integrative Agriculture 2013年第9期12卷 1589-1597页

作者： WU Chun-xian NIE Guo ZHang Zhong-ming Wang Guang-cheng GAO Li-ming Wang Jin-jun College of Plant Protection Southwest University Institute of the Control of Agrochemical of Sichuan Province

Methiopyrisulfuron is a novel sulfonylurea herbicide with good activity for annual broadleaf and gramineal weeds control. Present study was to investigate the effects of organic amendments （including peat （PE）, sewage sludge （SS）, and humic acid （ha）） on adsorption, desorption and leaching of methiopyrisulfuron in soils. The batch equilibration technique was applied for adsorption-desorption experiments and the leaching was tested through soil column simulated experiments under laboratory conditions. The Freundlich model may well describe adsorption-desorption of methiopyrisulfuron on organic amendments, the natural soil, and amended soils. Organic amendments could not only greatly increase the adsorption capacity of methiopyrisulfuron, but also significantly enhance the hysteresis of desorption of methiopyrisulfuron. The correlations between Kf_ads and organic matter content of amended soils were significant, and the correlations between H and soil organic matter in amended soils with PE, SS, and ha were significant too. The results of soil column experiments indicated that organic amendments greatly decreased leaching of methiopyrisulfuron. This study suggested that PE, SS, and ha could greatly influence environmental behavior of methiopyrisulfuron in soils. Use of organic amendments might be an effective management practice for controlling potential pollution of methiopyrisulfuron to environment.

关键词： organic amendment adsorption desorption leaching methiopyrisulfuron soil

Multiresponsive Spin Crossover Driven by Rotation of Tetraphenylborate Anion in an Iron(Ⅲ)Complex

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CCS Chemistry 2021年第1期3卷 453-459页

作者： Si-GuoWu Md.Najbul Hoque Jie-Yu Zheng Guo-Zhang Huang Nguyen Vu ha Anh Liviu Ungur Wei-Xiong Zhang Zhao-Ping Ni ming-Liang Tong Key Laboratory of Bioinorganic and Synthetic Chemistry of Ministry of Education School of ChemistrySun Yat-Sen UniversityGuangzhou 510275 Department of Chemistry National University of SingaporeSingapore 117543

Dynamic molecular materials,which involvemechanical motions in crystals,usually exhibit tunable properties related to conformational ***,we describe a solvent-free molecular crystal[{FeⅢ(salten)}2(TPB)](BPh_(4))_(2)(Ⅰ)developed by associating the rotatable tetraphenylborate anion with the spin crossover(SCO)binuclear iron(Ⅲ)*** solvent-free phaseⅠcan undergo a temperature-induced phase transformation to phaseⅡ,during which rotation of the BPh4−anion interplays with the SCO component,giving rise to fascinating variations in SCO(from gradual to abrupt)and dielectric *** importantly,an unexpected polymorphic transformation fromⅡtoⅢorⅣ,with increasing magnetic hysteresis,is realized by exposingⅡto water or ethanol vapor;the transition is reversible by *** rare successive transformation is further rationalized by theoretical ***,this multiresponse system provides a new way for modulating synergistic effects and designing dynamic SCO materials by integrating intramolecular motions in the crtystal lattice.

关键词： intramolecular motion iron(Ⅲ) spin crossover polymorph single-crystal-to-singlecrystal transformation

Characterization on Modification and Biocompatibility of PCL Scaffold Prepared with Near-field Direct-writing Melt Electrospinning

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Chemical Research in Chinese Universities 2021年第3期37卷 578-583页

作者： CHEN Zhijun haO ming QIAN Xiaoming CHEN Wenyang ZENG ming HUang Juan LI Ruixin FAN Jintu LIU Yanbo School of Textile Science and Engineering State Key Laboratory of Separation Membranes and Membrane ProcessesTiangong UniversityTianjin300387P.R.China School of Textile Science and Engineering Key Laboratory of Textile Fiber and ProductMinistry of EducationWuhan Textile UniversityWuhan430200P.R.China Central Laboratory Tianjin300041P.R.China Tianjin Stomatological Hospital Tianjin Key Laboratory of Oral and Maxillofacial Function ReconstructionTianjin300041P.R.China

In this study,orthogonal experiments were designed to explore the optimal process parameters for preparing polycaprolactone(PCL)scaffolds by the near-field direct-writing melt electrospinning(NFDWMES)*** on the optimal process parameters,the PCL scaffolds with different thicknesses,gaps and structures were manufactured and the corresponding hydrophilicities were *** PCL scaffolds were modified by chitosan(CS)and hyaluronic acid(ha)to improve biocompatibility and *** Fourier transform infrared spectroscopy(FTIR)analysis and antibacterial experimental results show that the chitosan and hyaluronic acid adhere to the surface of PCL scaffolds,suggesting that the modification plays a positive role in biocompatibility and antibacterial *** PCL scaffolds were then employed as a carrier to culture *** morphology and distribution of the cells observed by a fluorescence microscope demonstrate that the modified PCL scaffolds have good biocompatibility,and the porous structure of the scaffolds is conducive to adhesion and deep growth of cells.

关键词： Melt electrospinning Near-field direct-writing Tissue engineering scaffold Polycaprolactone Modification

Effects of Dan-shao-hua-xian on expression of PPAR-gamma and NF-kappa B in rat liver fibrosis

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Hepatobiliary & Pancreatic Diseases International 2008年第2期7卷 179-184页

作者： Wang, He-Yan Cheng, ming-Liang Affiliated Hosp Guiyang Med Coll Dept Infect Dis Guiyang 550004 Peoples R China

BACKGROUND: Peroxisome proliferator-activated receptor gamma (PPAR-gamma) and nuclear factor kappa B (NF-kappa B) play important roles in liver fibrosis. This study aimed to investigate the effects of Dan-shao-hua-xian, a preparation of traditional Chinese medicine, on the expression of PPAR-gamma and NF-kappa B in the fibrotic livers of rats. METHODS: Seventy Wistar rats were randomly divided into 4 groups: treatment (model, 8 weeks+treatment, 8 weeks; group A), natural recovery (model, 8 weeks+ saline, 8 weeks; group B), model (model only, 8 weeks; group Q, and control (normal, untreated, 16 weeks; group D). Each group consisted of 20 rats (except for group D, which had 10). Fibrotic liver models were induced in rats by subcutaneous injection of CCI4, oral administration of alcohol and a high-lipid/low-protein diet for 8 weeks. After the models were established, the rats in group A were orally given Dan-shao-hua-xian capsules daily for another 8 weeks. Then, the liver indices serum hyaluronic acid (ha), tumor necrosis factor-alpha (TNF-alpha) and alanine aminotransferase (ALT) were measured. The degree of hepatic fibrosis was evaluated by optical microscopy. Hydroxyproline (Hyp) in the liver tissue was determined. The expression of PPAR-gamma was detected by immunohistochemical techniques. The protein levels of PPAR-gamma and NF-kappa B were determined by Western blotting. RESULTS: The concentrations of serum ha, TNF-alpha and Hyp in group C increased compared with group D (Phat the expression of PPAR-gamma in group C decreased compared with group D, and it increased in group A compared with group C. The expression of NF-kappa B increased in group C compared with group D (P<0.05), and it decreased in group A compa

关键词： Dan-shao-hua-xian capsules peroxisome proliferator-activated receptors NF-kappa B hepatic fibrosis

Effect of matrine on Kupffer cell activation in cold ischemia reperfusion injury of rat liver

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World Journal of Gastroenterology 2002年第6期8卷 1112-1116页

作者： ming-KeShi Yu-DongQiu haoShen Yi-TaoDing BiochemistryDepartmentofNanjingUniversity Nanjing210008China DepartmentofHepatobiliarySurgery AffiliatedDrumTowerHospitalMediealDepartmentofNanjingUniversityNanjing210008JiangsuProvinceChina

AIM:To study the effect of matrine on activation of Kupffer cell during cold ischemia and reperfusion injury in rat orthotopic liver transplantation(OLT).

关键词：大鼠肝缺血冷缺血再灌注损伤苦参碱肝枯否细胞

Value Estimation of Greenhouse Gases Exchange in Wetland Ecosystem of Sanjiang Plain,China

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Chinese Geographical Science 2009年第1期19卷 55-61页

作者： LIU Xiaohui LU Xianguo JIang ming Wang Xigang Key Laboratory of Wetland Ecology and Environment Northeast Institute of Geography and Agroeeology Chinese Academy of Sciences Changchun 130012 China Graduate University of the Chinese Academy of Sciences Beijing 100049 China Hella Automotive Lighting Limited Company Changchun 130033 China

The objective of this study is to quantify the values of greenhouse gases(GHGs) exchange in carbon equivalents of marshes and paddy fields in the Sanjiang Plain,Heilongjiang Province,China. We obtained the GHGs exchange values based on comparable price by calculating the carbon sequestration values and the GHGs emission values of marshes and paddy fields respectively in four periods of 1982,1995,2000 and 2005. It is noted that the GHGs emission values are always negative. In this study,the marshes areas decreased from 1438977.0 to 775,132.2ha and the paddy fields areas increased from 417195.8 to 934205.0ha. The values of GHGs exchange of marshes varied from 135877.156×106 to 136882.534×106 yuan(RMB) and those of paddy fields varied from 1006.256×106 to 2767.645×106 yuan. The GHGs exchange values of marshes decreased from 1982 to 2005 on the whole,reversely,those of paddy fields increased,but those in 2005 were lower than those in 2000. In different periods,the GHGs exchange values were always higher in marshes than in paddy fields. The contribution rate of GHGs exchange values per unit area of marshes was also very high in different periods,and the maximum was up to 98.35% in 2005. As far as the whole wetland ecosystem(including marshes and paddy fields) ,assuming a linear change in GHGs exchange values,it represented a cumulative increase of 20926.757×106 yuan from 1982 to 2005. By adding GHGs exchange values increased during those four periods,we obtained a cumulative net increase values of GHGs exchange of wetland ecosystem of 18200.860×106 yuan. The results will be useful for understanding the indirect services provided by marshes and paddy fields.

关键词： carbon equivalents GHGs exchange values contribution rate cumulative value Sanjiang Plain