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Contact and fumigant toxicities of calamusenone isolated from Acorus gramineus rhizome against adults of Sitophilus zeamais and Rhizopertha dominica

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Insect Science 2011年第2期18卷 181-188页

作者： Yan-Zhang Huang Hong-Xia Hua shi-Guana li Chang-ju Yang College of Plant Protection Anhui Agricultural University Hefei College of Plant Science and Technology Huazhong Agricultural University Wuhan China

Calamusenone [3,8-dimethyl-5-（1-methylethylidene）- 1,2,3,4,5,6,7,8-octa- hydroazulene-6-one, C15H22O] from Acorus gramineus Soland rhizome was tested in the laboratory for its insecticidal activities against adults of Sitophilus zeamais Motsch. and Rhizopertha dominica （Fab.）, using dry film contact and fumigation methods. Responses varied with insect species, dosage and exposure time. In the dry film contact experiment, the highest insecticidal effects of calamusenone against S. zeamais and R. dominica adults were produced at 170.32μg/cm2 after treatment for 72 h, with 96.2% and 98.7% mortalities, respectively. The median lethal concentration （LC50）（72 h） values of calamusenone against S. zeamais and R. dominica adults were 67.00 μg/cm2 and 77.30 μg/cm2, respectively. As a potential fumigant, calamusenone showed moderate insecticidal effect on the adults of S. zeamais and R. dominica in fumigation experiment, with their LC50 （120 h） values of 125.71μL/L and 93.64μL/L respectively. Calamusenone isolated from A. gramineus rhizome showed promise as a novel pesticide candidate for stored-product pest control.

关键词： Acorus gramineus Soland calamusenone insecticide Rhizopertha dominica(Fab.) Sitophilus zeamais Motsch.

Two new olean-type triterpene fatty esters from Scorzonera mongolica

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Chinese Chemical Letters 2007年第6期18卷 708-710页

作者： Bin Wang Guo Qiang li Pei ju Qiu Hua shi Guan Institute of Marine Drugs and Food of Ocean University of China Qingdao 266003 China

Two new triterpene fatty esters, 3β-tetradecanoyl moradiol 1 and 3β-dodecanoyl moradiol 2, were isolated from Scorzonera mongolica. Their structures were elucidated as 3β-tetradecanoyloxy-28-hydroxylolean-18-ene and 3β-dodecanoyl-28-hydroxyl-olean-18-ene on the basis of IR, MS, 1D NMR and extensive 2D NMR spectroscopic analyses.

关键词： Scorzonera mongolica Moradiol Triterpene fatty esters

Review of the LNG intermediate fluid vaporizer and its heat transfer characteristics

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Frontiers in Energy 2022年第3期16卷 429-444页

作者： Shu li Yonglin ju Institute of Refrigeration and Cryogenics Shanghai Jiao Tong UniversityShanghai200240China

The intermediate fluid vaporizer (IFV), different from other liquefied natural gas (LNG) vaporizers, has many advantages and has shown a great potential for future applications. In this present paper, studies of IFV and its heat transfer characteristics in the LNG vaporization unit E2 are systematically reviewed. The research methods involved include theoretical analysis, experimental investigation, numerical simulation, and process simulation. First, relevant studies on the overall calculation and system design of IFV are summarized, including the structural innovation design, the thermal calculation model, and the selection of different intermediate fluids. Moreover, studies on the fluid flow and heat transfer behaviors of the supercritical LNG inside the tubes and the condensation heat transfer of the intermediate fluid outside the tubes are summarized. In the thermal calculations of the IFV, the selections of the existing heat transfer correlations about the intermediate fluids are inconsistent in different studies, and there lacks the accuracy evaluation of those correlations or comparison with experimental data. Furthermore, corresponding experiments or numerical simulations on the cryogenic condensation heat transfer outside the tubes in the IFV need to be further improved, compared to those in the refrigeration and air-conditioning temperature range. Therefore, suggestions for further studies of IFV are provided as well.

关键词： intermediate fluid vaporizer design of structure and intermediate fluid condensation heat transfer

Berberine as an Environmental-Friendly Inhibitor for Hot-Dip Coated Steels in Diluted Hydrochloric Acid

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Journal of Materials Science & Technology 2012年第9期28卷 809-816页

作者： Hong ju Yulin ju Yan li College of Mechanic and Electronic Engineering China University of PetroleumQingdao 266555China

The inhibition effect of an excellent environmental-friendly corrosion inhibitor--berberine on hot-dip coated steels in the diluted HCI has been investigated by using quantum chemistry analysis, mass-loss tests, elec- trochemical measurements and scanning electron microscopy （SEM） observation. Calculation results show that berberine has a nearly planar structure with a number of active centers. The value of Mulliken charge, and the distribution of the highest occupied molecular orbital （HOMO） and the lower unoccupied molecular orbital （LUMO） imply that berberine has a good ability of electron exchange with metal surface. The test results indicate that inhibition efficiency （IE%） increases with the inhibitor concentration and the highest IE can reach 99%. Adsorption of berberine on the coating surface follows Langmuir adsorption isotherm with a single molecular layer by chemisorption.

关键词： Berberine Inhibition effects Hot-dip coated steel Corrosion

Selective binding of unsaturated aliphatic hydrocarbons by a pillar[5]arene

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Chinese Chemical Letters 2013年第8期24卷 707-709页

作者： Xiao-shi Hu Hong-Mei Deng Jian li Xue-Shun Jia Chun-ju li Department of Chemistry Shanghai University

The complexation behavior of unsaturated fatty hydrocarbons,i.e.,1,7-octadiyne and 1,7-octadiene,by a perethylated pillar[5]arene has been investigated,which was compared with that for saturated n-octane. It was found that the host-guest binding strength increased in accordance with the electron-negativity of the terminal carbon atom on the guests：alkyne〉alkene〉alkane.

关键词： Molecular recognition Pillararenes Unsaturated hydrocarbons Supramolecular chemistry

Climate effects of the GlobeLand30 land cover dataset on the Beijing Climate Center climate model simulations

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Science China Earth Sciences 2016年第9期59卷 1754-1764页

作者： shi Xueli NIE SuPing ju WeiMin YU Le National Climate Center Beijing 100081 China International Institute for Earth System Science (ESSI) Nanjing University Nanjing 210093 China Ministry of Education Key Laboratory for Earth System Modeling Center for Earth System Science Tsinghua University Beijing 100084 China Joint Center for Global Change Studies Beijing 100875 China

Land cover is one of the most basic input elements of land surface and climate models. Currently, the direct and indirect effects of land cover data on climate and climate change are receiving increasing attentions. In this study, a high resolution(30 m) global land cover dataset(Globe Land30) produced by Chinese scientists was, for the first time, used in the Beijing Climate Center Climate System Model(BCC_CSM) to assess the influences of land cover dataset on land surface and climate simulations. A two-step strategy was designed to use the Globe Land30 data in the model. First, the Globe Land30 data were merged with other satellite remote sensing and climate datasets to regenerate plant functional type(PFT) data fitted for the BCC_CSM. Second, the up-scaling based on an area-weighted approach was used to aggregate the fine-resolution Globe Land30 land cover type and area percentage with the coarser model grid resolutions globally. The Globe Land30-based and the BCC_CSM-based land cover data had generally consistent spatial distribution features, but there were some differences between them. The simulation results of the different land cover type dataset change experiments showed that effects of the new PFT data were larger than those of the new glaciers and water bodies(lakes and wetlands). The maximum value was attained when dataset of all land cover types were changed. The positive bias of precipitation in the mid-high latitude of the northern hemisphere and the negative bias in the Amazon, as well as the negative bias of air temperature in part of the southern hemisphere, were reduced when the Globe Land30-based data were used in the BCC_CSM atmosphere model. The results suggest that the Globe Land30 data are suitable for use in the BCC_CSM component models and can improve the performance of the land and atmosphere simulations.

关键词： Land cover Climate model Application strategy Numerical simulation Air temperature Precipitation

Fe-Mo-B Enhanced Sintering of P/M 316L Stainless Steel

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Journal of Iron and Steel Research International 2008年第1期15卷 10-14页

作者： YANG Xia GUO shi-ju Institute of Powder Metallurgy University of Science and Technology Beijing Beijing 100083 China

liquid-phase enhanced sintering of powder metallurgy（P/M）316L stainless steel by addition of sintering aids was studied.2%-8% of pre-alloyed Fe-Mo-B powder with two different particle sizes was added as sintering aids,and the specimens were sintered in vacuum at 1 200-1 350 ℃.The results show that the fine Fe-Mo-B powder（5-10 μm）has stronger activated *** sintered density increases with the increase in sintering aid content or sintering *** compaction has a better effect on the control of dimensional precision of *** prealloyed Fe-Mo-B powder deviated from Mo2FeB2 component can also be sintering aid of P/M 316L stainless steel.

关键词： P/M 316L stainless steel liquid-phase sintering activated sintering Fe-Mo-B sintering aid

PCR-DGGE Analysis of Nematode Diversity in Cu-Contaminated Soil

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Pedosphere 2008年第5期18卷 621-627页

作者： WANG shi-Bin li Qi liANG Wen-ju JIANG Yong JIANG Si-Wei Key Laboratory of Terrestrial Ecological Process Institute of Applied Ecology Chinese Academy of Sciences Shenyang110016 （China）.

A wheat pot experiment was conducted under greenhouse conditions to assess the effect of copper contamination on soil nematode diversity by polymerase chain reaction-denaturing gradient gel electrophoresis （PCR-DGGE） method and morphological analysis. The soil was treated with CuSO4.5H2O at the following concentrations： 0, 50, 100, 200, 400, and 800 mg kg^-1 dry soil, and the soil samples were collected at wheat jointing and ripening stages. Nematode diversity index （H′） from morphological analysis showed no difference between the control and the treated samples in either of the sampling dates. At the wheat ripening stage, nematode diversity obtained by the PCR-DGGE method decreased noticeably in the Cu800 treatment in comparison with the control. With optimization of the method of nematode DNA extraction, PCR-DGGE could give more information on nematode genera, and the intensity of the bands could reflect the abundance of nematode genera in the assemblage. The PCR-DGGE method proved promising in distinguishing nematode diversity in heavy metal coritaminated soil.

关键词： copper contamination morphological analysis nematode diversity PCR-DGGE

Experimental Study on Diesel Spray and Flame Asymmetry Characteristics of Dual-Orifice Nozzles for a Medium-Speed Engine

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Journal of Thermal Science 2025年第1期 303-322页

作者： ju Dehao liU Rui ZHENG liang DENG Jiahui ZHANG Wenzheng HUO Jinlu HUANG li Shanghai Marine Diesel Engine Research Institute National Key Laboratory of Marine Engine Science and Technology Key Laboratory for Power Machinery and Engineering Ministry of EducationShanghai Jiao Tong University

The asymmetry of the multi-orifice spray will cause uneven heat load of the marine diesel engine,thereby affecting its working performance and service ***,an in-depth understanding of the spray and flame characteristics of multi-orifice nozzles will guide the optimization of the nozzle structure,needle design and diesel atomization and combustion *** this reason,four groups of dual-orifice nozzles with different hole diameters(0.1-0.55 mm) and mass flow rates covering the typical marine medium-speed diesel injections are designed and customized,and the constant volume chamber(CVC) with high temperature and pressure is used to simulate the actual in-cylinder working conditions of the diesel engine for the spray visualization *** study the asymmetry of the fuel sprays discharged from a diesel injector,the multi-orifice nozzle is simplified as a dual-orifice nozzle in this *** with X-ray Computed Tomography(CT) imaging technology,the influences of the nozzle internal structure on the spray and flame asymmetry are studied in the constructed supercritical *** is found that the asymmetry of the inlet angle and the equivalent length-diameter ratio is positively correlated with the inconsistency of the dual *** an increase in the injection pressure and nozzle diameter,the asymmetry of the dual spray becomes more pronounced,resulting in greater disparities in the ignition delay times and ignition positions of the two ***,the increase in nozzle diameter also leads to combustion instability,resulting in a flame with a serrated *** the increase of ambient temperature,the proportion of liquid phase in the jet decreases and the relative density of spray front decreases.

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