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Chinese Journal of Structural Chemistry 2006年第8期25卷 903-908页

作者： LI Jing-Zhi XUE Si-Jia liu guo-hua Department of Chemistry College of Life and Environmental Science Shanghai Normal University Shanghai 200234 China

The title compound （R）-N′-[2-（4-methoxy-6-chloro）-pyrimidyl]-N-[3-methyl-2-（4- chlorophenyl）butyryl]-urea has been synthesized, and its crystal structure and biological behaviors were studied. Crystallographic data： C17H18C12N4O3, Mr = 397.25, monoclinic, space group P21/c, a = 12.331（2）, b = 14.025（3）, c = 23.085（5） A, β = 99.607（4）°, Z = 8, V = 3936.2（13） A3, Dc = 1.341 g/cm^3, F（000） = 1648, R = 0.0718, wR = 0.1585 and/t（MoKα） = 0.353 mm^-1. The preliminary biological tests showed that the title compound has definite insecticidal and fungicidal activities.

关键词： crystal structure biological activity (R)-3-methyl-2-(4-chlorophenyl)butyric acid 2-amino-6-chloro-4-methoxy-pyrimidine

A NEW METHOD OF CHANNEL FRICTION INVERSION BASED ON KALMAN FILTER WITH UNKNOWN PARAMETER VECTOR

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Journal of Hydrodynamics 2005年第6期17卷 693-698页

作者： CHENG Wei-ping MAO Gen-hai liu guo-hua College of Civil Engineering and Architecture Zhejiang University Hangzhou 310027 China

Channel friction is an important parameter in hydraulic analysis. A channel friction parameter inversion method based on Kalman Filter with unknown parameter vector is proposed. Numerical simulations indicate that when the number of monitoring stations exceeds a critical value, the so lution is hardly affected. In addition, Kalman Filter with unknown parameter vector is effective only at unsteady state. For the nonlinear equations, computations of sensitivity matrices are time-costly. Two simplified measures can reduce computing time, but not influence the results. One is to reduce sensitivity matrix analysis time, the other is to substitute for sensitivity matrix.

关键词： channel inversion Kalman Filter with unknown parameter vector friction

COMPUTATION OF TURBULENT FLOWS WITH COMPLEX BOUNDARIES

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Journal of Hydrodynamics 1991年第2期3卷 99-106页

作者： Fu, Song Zhang, Zhao-shun liu, guo-hua Tsinghua Univ Beijing China

Numerical simulations of steady, incompressible turbulent flows with complex boundaries are presented in this article. The complex boundary geometries are accurately represented via a boundary-fitted orthogonal coordinate system generated by the solution of a set of elliptic partial-differential equations (PDEs). Thus, an irregular physical space can be mapped into a rectangular computational domain. The Turbulent flow is described by time-averaging technique in which the κ-Ε two-equation-type Boussinesq-viscosity model (BVM) is employed to represent the resulting turbulence quantities, Reynolds stresses u,uj¯. Numerical solution is then obtained by solving the transport equations in their physical-component forms derived through the coordinate transformation from Cartesian coordinates to the orthogonal ones. Solution algorithm employs finite-volume method, with SIMPLE procedure to determine pressure field. The combined procedures are tested in a single-sided sudden-expansion flow situation. Computational results show favourable agreement with experiment data, indicating that curvilinear-orthogonal coordinate system can be incorporated into turbulent flow computations. A further computation of a pipe flow with rapidly converging/diverging wall provides confirming results.

关键词： Mathematical Techniques Geometry Viscosity

Hydrogen Sulfide May Function Downstream of Nitric Oxide in Ethylene-Induced Stomatal Closure in Vicia faba L.

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Journal of Integrative Agriculture 2012年第10期11卷 1644-1653页

作者： liu Jing HOU Zhi-hui liu guo-hua HOU Li-xia liu Xin Key Laboratory of Plant Biotechnology in Universities of Shandong Province/College of Life Science Qingdao Agricultural University

Pharmacological, laser scanning confocal microscopic （LSCM）, and spectrophotographic approaches were used to study the roles of hydrogen sulfide （H2S） and nitric oxide （NO） in signaling transduction of stomatal movement in response to ethylene in Viciafaba L. Ethylene treatment resulted in the dose-dependent stomatal closure under light, and this effect was blocked by the inhibitors of H2S biosynthesis in V. faba L. Additionally, ethylene induces H2S generation and increases L-/D-cysteine desulfhydrase （pyridoxalphosphate-dependent enzyme） activity in leaves of V. faba L. Inhibitors of H2S biosynthesis have no effect on the ethylene-induced stomatal closure, NO accumulation, and nitrate reductase （NR） activity in guard cells or leaves of II. faba L. Moreover, the ethylene-induced increase of H2S levels and L-/D- cysteine desulfhydrase activity declined when NO generation was inhibited. Therefore, we conclude that H2S and NO probably are involved in the signal transduction pathway of ethylene-induced stomatal closure. H2S may represent a novel component downstream of NO in the ethylene-induced stomatal movement in V. faba L.

关键词： hydrogen sulfide nitric oxide ethylene stomatal closure Vicia faba L.

Synthesis and application of an IL-supported diol as protecting group for aldehydes

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Chinese Chemical Letters 2007年第10期18卷 1205-1208页

作者： Yue Qin Cai Ye liu guo hua Gao Shanghai Key Laboratory of Green Chemistry and Chemical Processes East China Normal University Shanghai 200062 China

A new IL-supported diol, 1-（2,3-dihydroxypropyl）-3-methylimidazolium hexafluorophosphate has been synthesized and characterized by Fr-IR, ^1H NMR, ^13C NMR and MS （ESI）. Its physical properties such as freezing point, solubility and specific gravity and thermal stability were determined. Synthetic utilities of the resultant diol as a protecting group for aldehydes were also investigated.

关键词： IL-supported diol Preparation Characterization Protecting group

Crystal Structure of (R)-3,3′-Bis(benzyloxymethyl)-1,1′-bi-2,2′-naphthol and Its Applications in Enantioselective Lewis Acid Catalyzed Addition of Diethylzinc to Aldehydes

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Chinese Journal of Structural Chemistry 2007年第2期26卷 133-138页

作者： liu guo-hua YU Han XUE Yun-Ning YAO Mei FANG Hai-Bin Department of Chemistry College of Life and Environmental Science Shanghai Normal University Shanghai 200234 China

The title compound （R）-3,3＇-bis（benzyloxymethyl）-1,1＇-bi-2,2＇-naphthol （R）-3 has been synthesized through the deprotection of MOM group by iprOH/HCl in 83% isolated yield and the suitable single crystals for X-ray diffraction were obtained by recrystallization at room temperature from the mixture solvents. Crystallographic data for （R）-3： C36H30O4, Mr = 526.60, triclinic, space group P1, a = 10.057（6）, b = 11.934（7）, c = 12.314（6） A, α = 85.52（2）, β = 70.245（13）, γ = 76.554（11）°, Z= 2, V 1352.8（13） A^3, Dc = 1.293 g/cm^3, F（000） = 556, R = 0.0745, wR = 0.1933 and #（MoKa） = 0.083 mm^-1. The title compound （R）-3 was found to be effective in the enantioselective addition of diethylzinc to aldehydes both in the presence and absence of Ti（Oipr）4. In the latter case, （R）-3 showed much higher catalytic activity and enantioselectivity than （R）-BINOL＇s.

关键词： crystal structure BINOL derivative asymmetric addition

Regulatory Function of Polyamine Oxidase-Generated Hydrogen Peroxide in Ethylene-Induced Stomatal Closure in Arabidopsis thaliana

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Journal of Integrative Agriculture 2013年第2期12卷 251-262页

作者： HOU Zhi-hui liu guo-hua HOU Li-xia WANG Lan-xiang liu Xin College of Life Sciences Qingdao Agricultural University/University Key Laboratory of Plant Biotechnology in Shandong Province Universities of Shandong

Hydrogen peroxide （H2O2） is an important signaling molecule in ethylene-induced stomatal closure in Arabidopsis thaliana. Early studies on the sources of H2O2 mainly focused on NADPH oxidases and cell-wall peroxidases. Here, we report the involvement of polyamine oxidases （PAOs） in ethylene-induced H2O2 production in guard cells. In Arabidopsis epidermal peels, application of PAO inhibitors caused the failure of ethylene to induce H2O2 production and stomatal closure. Results of quantitative RT-PCR analysis and pharmacological experiments showed that AtPAO2 and AtPAO4 transcripts and activities of PAOs were both induced by ethylene. In transgenic Arabidopsis plants over-expressing AtPAO2 and AtPAO4, stomatal movement was more sensitive to ethylene treatment and H2O2 production was also significantly induced. The increased H2O2 production in the transgenic lines compared to the wild-type plants suggests that AtPAO2 and AtPAO4 probably are involved in ethylene-induced H2O2 production. Several factors which induce stomatal closure such as dehydration and high salinity all enhanced the expression of AtPAO2 and AtPAO4 to different degrees. Moreover, GFP- AtPAOs fusion protein localized in the nucleus, cytoplasm, and cell wall of the guard cells. Therefore, our results strongly indicated that PAO is a source of H2O2 generation in Arabidopsis guard cells and plays crucial roles in stomatal movement.

关键词： Arabidopsis thaliana ethylene guard cell hydrogen peroxide polyamine oxidase

“Double low-points” anomaly in daily variation of vertical component of geomagnetic field before the M_S8.0 Wenchuan earthquake

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Earthquake Science 2009年第5期22卷 539-543页

作者： Jiuchang Hu Wei liu Minrui guo hua Zheng Earthquake Administration of Hainan Province Haikou 570203 China

The ＂double low-points＂ anomaly in daily variation of vertical geomagnetic component was observed on May 9, 2008 at 13 geomagnetic observatories belonging to the geomagnetic observatory network center of China Earthquake Administration. These observatories distribute roughly on three belts with the intersection in western Sichuan. On May 12, three days after the anomaly appearance, the great Ms8.0 Wenchuan earthquake occurred. The ＂double low-points＂ anomaly in daily variation of vertical geomagnetic component is an anomalous phenomenon of regional geomagnetism, which does exist objectively. The possible cause is the change of extrinsic eddy current system resulting in geomagnetic daily quiet variation （Sq）, or the delay of several hours between the intrinsic and the extrinsic eddy current systems. The relationship between the ＂double low-points＂ anomaly of daily geomagnetic variation and the earthquake reveals that the former possibly reflects the accelerative alteration of earthquake gestation in the deep Earth.

关键词： Wenchuan earthquake geomagnetism vertical component double low-points

Economic value of freshwater provisioning services of the cryosphere in the Urumqi River, Northwest China

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Advances in Climate Change Research 2021年第6期12卷 894-902页

作者： ZHANG Xue-Ting CHEN Ren-Sheng liu guo-hua YANG Yong FENG Tian-Wen Qilian Alpine Ecology and Hydrology Research Station Northwest Institute of Eco-Environment and ResourcesChinese Academy of SciencesLanzhou730000China University of Chinese Academy of Sciences Beijing100049China College of Urban and Environment Sciences Northwest UniversityXi'an710127China

As an important component of cryospheric provisioning services, freshwater provisioning services of the cryosphere is particularly critical to human well-being and socio-economic sustainability. It is imperative to quantitatively estimate the value of freshwater provisioning services to facilitate informed decision-making for ecosystem management and economic development. This study assessed the economic value and associated changes in benefits of freshwater provisioning services for industrial, agricultural, services and domestic water uses combining cost-based method and hydrological model in the Urumqi River during 2010–2016. The results showed that the average annual economic value of agricultural, services, domestic and industrial water uses generated from freshwater provisioning services were estimated to be 1.7, 4.4, 9.9, and 15.7 million CNY. The annual value of snowmelt provisioning services of sectorial water uses was much higher than that of glacier meltwater due to the greater contribution of snowmelt to outlet streamflow than glacier melt. The relative contributions of agricultural, services, domestic and industrial sectors to total economic value of freshwater provisioning services were 6%, 13%, 32%, and 49% respectively, depending on the meltwater supply and market prices. The benefits of freshwater provisioning services from different sectors generally increased in 2010–2016, with a significant increase in the services sector. Considering the impact of changes in freshwater supply under climate change on the assessment of cryospheric provisioning services, the results emphasize the necessity of promoting industrial structure optimization and adopting resource-efficient policies.

关键词： Freshwater provisioning services Economic value Cost-based method CBHM model Urumqi river

Protection Methods to Reduce Nitrogen and Phosphorus Losses from Sloping Citrus Land in the Three Gorges Area of China

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Pedosphere 2015年第3期25卷 478-488页

作者： XIA Li-Zhong liu guo-hua WU Yong-Hong MA Li LI Yun-Dong Institute of Soil Science Chinese Academy of Sciences

The increased application of chemical fertilizers in citrus orchards and the non-point source nitrogen(N) and phosphorus(P)diffusion threaten the fresh water quality of the Three Gorges Reservoir area of China. A 10-year field trial on sloping citrus lands was conducted to evaluate five protection methods for reducing N and P losses: 1) intercropping with perennial white clover(CW); 2) straw mulching of the soil surface(CS); 3) intercropping with yellow daylily contour hedgerows(CH); 4) an impermeable membrane buried in the soil along the contour lines(CM); and 5) intercropping with a rotation of wheat and peanut(CWP). An area of conventional citrus management was also maintained as the control(CK). The results showed that CM and CH were the most effective methods for reducing surface runoff. The sediment yield were reduced at the highest rate by CW and CH and was also significantly reduced by CS. Reduced runoff volume and sediment yield were the crucial mechanism for the reductions in N and P losses. Compared with the control, CW, CS, CH, and CM reduced annual runoff by 9%, 13%, 25%, and 30%, sediment yield by 77%, 55%, 71%, and 28%,N loss by 10%, 23% 36%, and 37%, and P loss by 39%, 31%, 27%, and 25%, respectively. CW, CS, CH, and CM were effective in reducing N and P losses from the sloping citrus land. However, over the long-term, surface soil nutrient accumulation in CW, CS, and CH diminished the benefit of those methods in reducing N and P losses. In addition, CWP increased soil erosion and nutrient loss,which showed that citrus intercropping with other crops was an unsuitable method for citrus sloping land in the Three Gorges area.

关键词： contour hedgerows impermeable membrane intercropping runoff sediment straw mulching