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Differential effects of short term winter thermal stress on diapausing tiger swallowtail butterflies （Papilio spp.）

Insect Science 2012年第3期19卷 277-285页

作者： j. Mark Scriber Emily Maher Matthew l. Aardema Department of Entomology Michigan State University East Lansing MI McGuire Center for lepidoptera and Biodiversity Florida Museum of Natural History University of Florida Gainesville FL Department of Ecology and Evolutionary Biology Princeton University Princeton N J USA

It is generally thought that insects inhabiting lower latitudes are more severely impacted by changes in their thermal environment than are high latitude species. This is attributed to the wider range of temperatures to which high-latitude species are exposed. By contrast, low-latitude species have typically evolved in more thermally stable environments with a narrower range of temperature variation. However, deviation from this pattern can occur and here we report that under variable winter conditions a higher latitude species may be more sensitive to thermal variation than its lower latitude sister species. Using split broods, we examined the survival and adult emergence success of diapausing pupae of Papilio canadensis and P. glaucus, as well as a unique, recombinant hybrid population （＂late-flight＂） to short periods of mid-winter cold and heat stress. Our results indicate that the higher latitude, univoltine populations （P. canadensis and late-flights） exhibit lower pupal survival than the lower latitude, facultative diapauser （P. glaucus） for all mid-winter thermal stress treatments, both high and low. Size differences alone do not appear to account for the observed differences in survival or metabolic costs in these three pheno- types, as late-flight individuals are similar in size to R glaucus. We attribute the observed differences in survival and weight loss to potential metabolic differences and variation in the intensity of diapause, in addition to divergent adaptation to winter precipitation levels （e.g. snow cover） and the influences this may have on microhabitat temperature moderation.

关键词： climate change developmental threshold incipient hybrid species metabolic cost Papilionidae post-diapause delays thermal stress

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Ecological and Economic Benefits of Vegetation Management Measures in Citrus Orchards on Red Soils

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Pedosphere 2008年第2期18卷 214-221页

作者： SHUI j.an-Guo WANG Qiu-Zhen lIAO Gen-Qing j. AU j. l. AllARD Institute of Environmental Resources and Soil Fertilizer Zhejiang Academy of Agricultural Sciences Hangzhou 310021 （China） College of Management Zhejiang University Hangzhou 310027 （China） Soil ＆ Fertilizer Station of Wucheng District Jinhua 321000 （China） Syngenta （China） Investment Co. ltd. Shanghai 200041 （China） Syngenta Asia Pacific Pte. ltd. 250 North Bridge Road Singapore 179101 （Singapore）

A three-year experiment was conducted to investigate and compare the economic and ecological benefits of six types of vegetation management measures in citrus orchards of the hilly red soil region of the eastern part of *** vegetation treatments,including tillage without herbicide(clean tillage)and no tillage without herbicide(sod culture) and with herbicide paraquat(paraquat),glyphosate(glyphosate),glyphosate-glyphosate-paraquat(G-G-P),and paraquat- paraquat-glyphosate(P-P-G),were applied in the citrus orchards on a clayey red soil with slopes of 8°and 13°and a sandy soil with slope of 25°.The results showed that the sod culture,paraquat,glyphosate,G-G-P,and P-P-G treatments reduced surface runoff by 38.8%,42.5%,18.7%,28.7%,and 37.5%,then the soil-water losses by 55.5%,51.7%,39.9%,46.8%, and 50.0%,and the N,P,and K nutrient losses by 60.3%,50.2%,37.0%,41.8%,and 45.4%,respectively,as compared with the clean tillage *** weed regeneration ratios with the treatments of clean tillage without herbicide,paraquat, glyphosate,G-G-P,and P-P-G were reduced by 55.1%,67.2%,30.3%,36.8%,and 51.2%,respectively,as compared with the sod *** sod culture,paraquat,glyphosate,G-G-P,and P-P-G treatments could increase the soil fertility (annual accumulation of N,P,K,and OM)by 7.1%,6.9%,5.3%,6.2%,and 6.6%,respectively,whereas the clean tillage treatment without herbicide reduced soil fertility by 4.4% after the three-year *** citrus fruit yields in the treatments of paraquat,glyphosate,G-G-P,and P-P-G increased by 7%-10%;the soluble solid,total sugar,total acidity,sugar-acid ratio,and single fruit weight of citrus fruits of all treatments except sod culture significantly(P>0.05) exceeded that of the clean tillage *** general,the paraquat treatment showed the best economic and ecological benefits among the six treatments;therefore,it could be regarded as the best available vegetation management measure in citrus orchards of hilly red soil region

关键词： benefits citrus herbicide red soil vegetation management

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"反介入"战役及制胜要素——《反介入战争》第四章(三)

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兵器 2025年第1期 48-54页

作者： [美]萨姆·j.坦格里迪吴志丹(译) 不详

二战英国战役的胜利与纳粹失败的海狮行动被认为是二战转折点的英国战役,研究成果颇为丰硕。在纳粹对不列颠群岛发动空袭前,尽管德国海军在对英国海军和入侵挪威的战斗中不时会有损失,但德国陆军的“闪电战”从未失败过。

关键词：不列颠群岛英国海军研究成果纳粹转折点战役二战

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The N-terminus of COX-1 and its effect on cyclooxygenase-1 catalytic activity

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j.urnal of Genetics and Genomics 2010年第2期37卷 117-123页

作者： Sean Phipps Michael j. Turner Daniel l. Simmons Chemistry and Biochemistry Department Brigham Young University

Cyclooxygenases are encoded by COX-1 and COX-2. They share over sixty percent sequence identity in human and are similar to each other in their crystallographic structures. One maj.r difference in the primary structure of these two isozymes is the presence of eight amino acids in the amino-terminal region of COX-1 that are not present in COX-2. The function of this amino acid sequence is unknown. In this study, a human COX-1 mutant （Δ7aa） with this sequence removed was studied in parallel with COX-1. Signal peptide cleavage, N-linked glycosylation, protein expression, distribution and dimerization were not affected by the mutation. The mutant was enzymati-cally active and showed the same sensitivity toward aspirin. The KM for the enzyme remained the same as COX-1. However, the Vmax of the COX-1 mutant decreased by 3.3-fold. We conclude that the COX-1 specific amino-terminal sequence has a subtle but detectable effect on COX-1 catalysis.

关键词： COX-1 COX-2 dimerization glycosylation aspirin KM Vmax

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Effect of Silver Content on Microstructure and Properties of Brass/steel Induction Brazing j.int Using Ag-Cu-Zn-Sn Filler Metal

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j.urnal of Materials Science & Technology 2011年第4期27卷 377-381页

作者： j. Cao l.X. Zhang H.Q. Wang l.Z. Wu j.C. Feng State Keylab of AdvanCed Welding Production Technology Harbin Instituteof Technology Harbin 150001 China Center for Composite Materials and Structures Harbin Institute of Technology Harbin 150001 China

The induction brazing of brass to steel using Ag-Cu-Zn-Sn filler metal was investigated in this study. The influence of A8 content on the microstructure and properties were analyzed by means of optical microscopy, scanning electron microscopy and electron probe microanalysis. Defect free j.int was achieved using Ag- Cu-Zn-Sn filler metal. The microstructure of the j.int was mainly composed of Ag-based solid solution and Cu-based solid solution. The increase of A8 content and the cooling rate both led to the increase of the needle like eutectic structure. The tensile strength decreased with the increase of Ag content. The tensile strength at room temperature using Ag25CuZnSn filler metal reached 445 MPa. All fractures using Ag-Cu-Zn-Sn filler metal presented ductile characteristic.

关键词： Induction brazing Brass Steel Microstructure Tensile strength

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Consolidation of AA 7075-2 wt% ZrO2 Composite Powders by Severe Plastic Deformation via ECAP

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Acta Metallurgica Sinica(English letters) 2016年第10期29卷 895-901页

作者： S. E. Hernandez-Martinez j. j. Cruz-Rivera R. Martinez-Sanchez C. G. Garay-Reyes j. A. Mufioz-Bolanos j. M. Cabrera j.l.Hernández-Rivera Instituto de Metalurgia Universidad Autonoma de San Luis Potosi Sierra Leona 550 78210 San Luis Potosi Mexico Centro de Investigacion en Materiales Avanzados (CIMAV) Miguel de Cervantes 120 31109 Chihuahua Mexico Departamento de Ciencia de Materiales e Ingenieria Metalurgica Universitat Politecnica de Catalunya Av Diagonal 647 08028 Barcelona Spain Fundacion CTM Centro Tecnologico Plaza de la Ciencia 208243 Manresa Spain CONACYT Research Fellow-Instituto de Metalurgia Universidad Autonoma de San Luis Potosi- Sierra Leona 550 78210 San Luis Potosf Mexico

The powders of the AA 7075-ZRO2 were mixed by mechanical milling, but it was found that the system presents a few disadvantages when processed by conventional sintering and hot extrusion, since intermetallic phases between ZrO2 particles and alloying elements were formed. Equal channel angular pressing （ECAP） processing was proposed as an alternative method to consolidate the composite where there is no intermetallic formation. The analysis of the ECAP process showed that the intermediate temperature （220℃） produced a higher consolidation level than conventional sintering and hot extrusion （400 and 500℃, respectively）. This fact was supported by relative density analysis. In the case of the sintered and hot-extruded sample, the relative density exhibited a value of 0.95, while ECAP sample showed a value of 0.98. Hardness values show that microstructural refinement obtained during mechanical milling was preserved during ECAP processing even when it was carded out at 220℃.

关键词： Metal matrix composites (MMCs) Powder consolidation Severe plastic deformation (SPD)

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PREPARATION AND CORROSION RESISTANCE OF NiP/TiO_2 COMPOSite FIlM ON CARBON STEEl IN SUlFURIC ACID SOlUTION

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Acta Metallurgica Sinica(English letters) 2006年第2期19卷 117-123页

作者： l.Z. Song S.Z. Song j. Zhao School of Environment ＆ Chemical Engineering Yanshan University Qinhuangdao 066004 China School of Materials Science and Engineering Tianjin University Tianjin 300072 China

A NiP/TiO2 composite film on carbon steel was prepared by electroless plating and sol-gel composite process. An artificial neural network was applied to optimize the prepared condition of the composite film. Corrosion behavior of the NiP/TiO2 composite film was investigated by polarization resistance measurement, anode polarization, ESEM （environmental scanning electron microscopy） and EIS （electrochemical impedance spectroscopy） measurements. Results showed that the NiP/ TiO2 composite film has a good corrosion resistance in 0.5mol/l H2SO4 solution. The element valence of the composite film was characterized by XPS （X-ray photoelectron spectroscopy） spectrum, and an anticorrosion mechanism of the composite film was discussed.

关键词： electroless plating and sol-gel composite process artificial neural network NiP/TiO2 composite film corrosion resistance

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Diagnosis of bile duct hepatocellular carcinoma thrombus without obvious intrahepatic mass

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World j.urnal of Gastroenterology 2010年第39期16卷 4998-5004页

作者： long XY li YX Wu W li l Cao j. Department of General Surgery Xiangya Hospital Central South University Changsha 410008 Hunan Province China. liyixiong6@***

AIM:To study the diagnosis of hepatocellular carcinoma(HCC)presenting as bile duct tumor thrombus with no detectable intrahepatic ***:Six patients with pathologically proven bile duct HCC thrombi but no intrahepatic mass demonstrated on the preoperative imaging or palpated intrahepatic mass during operative exploration,were *** clinical and imaging data were retrospectively *** maj.r findings or signs on comprehensive imaging were correlated with the surgical and pathologic ***:j.undice was the maj.r clinical symptom of the *** elevated serum total bilirubin,direct bilirubin and alanine aminotransferase levels were in concordance with obstructive j.undice and the underlying liver *** the 6 patients showing evidence of viral hepatitis,5 were positive for serum alpha fetoprotein and carbohydrate antigen 19-9,and 1 was positive for serum carcinoembryonic *** patient was correctly diagnosed by *** main features of patients on comprehensive imaging were filling defects with cup-shaped ends of the bile duct,with large filling defects presenting as casting moulds in the expanded bile duct,hypervascular intraluminal nodules,debris or blood clots in the bile *** obvious circular thickening of the bile duct walls was ***:Even with no detectable intrahepatic tumor,bile duct HCC thrombus should be considered in patients predisposed to HCC,and some imaging signs are indicative of its diagnosis.

关键词： Hepatocellular carcinoma Obstructive j.undice Bile duct tumor thrombus Diagnosis Diagnostic imaging

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Mass-balance ecosystem model of the East China Sea

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Progress in Natural Science:Materials International 2009年第10期19卷 1271-1280页

作者： William W.l. Cheung Tony j. Pitcher The Fisheries Centre University of British Columbia

Using the Ecopath mass-balance trophodynamic model,this paper analyzed the trophic levels,flows,food web structure and ecosystem maturity of the East China Sea,and identified ecologically important functional groups in the *** model is based on fishery resource surveys of the East China Sea in 2000,studies on diet composition and global databases such as FishBase and the Sea Around Us Proj.ct *** results showed that trophic levels of the functional groups are between 2.86 and 4.37,with an average of ***(Engraulis j.ponicus),small fishes and benthic crustaceans such as shrimps and crabs are important groups in terms of the trophic structure and flow dynamics in the East China *** flows of most groups are between specific trophic levels,except file fish(Thamnaconus spp.),pomfret(Pampus spp.) and *** transfer efficiency of levels Ⅱ,Ⅲ,IV and more than V are 11.8%,21.1%,17.4% and 22.1-22.5%,*** of fishery-the largest ‘consumer’ of the ecosystemare much stronger than those exerted by biological groups in the *** model suggests that the current fishery can further reduce the complexity of the *** of the system indices suggest that maturity of the ecosystem is *** conclusion of this model indicates that it was the overfishing that caused the ecosystem of the East China Sea declined,which should be taken into account as a critical reference for fisheries management in the future.

关键词： Ecopath East China Sea Mass-balance Fishery Ecosystem

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Maximizing biomass utilization: An integrated strategy for coproducing multiple chemicals

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j.urnal of Energy Chemistry 2025年第1期100卷 180-191页

作者： Byeongchan Ahn Sua j. j.nggeol Na j.j.y liu Young-j. Kim Wangyun Won Department of Chemical and Biological Engineering Korea University Department of Chemical Engineering (Integrated process) Kyung Hee University Department of Chemical Engineering and Materials Science Ewha Womans University Department of Chemical Engineering Pukyong National University Resources Engineering Plant Research Department Korea Institute of Geoscience and Mineral Resources

lignocellulosic biomass is one of the viable solutions to alleviate the global warming. However, the limited utilization of biomass maj.rly focused on cellulose and hemicellulose restricts the economic and environmental feasibilities. To cope with this issue, we proposed an integrated process of co-producing 1,6-hexanediol（1,6-HDO） with tetrahydrofuran and adipic acid from biomass, referred to as Strategy A. To compare the impacts of lignin upgrading and feedstock, Strategy B, which co-produces tetrahydrofuran alone, and Strategy C, which is the traditional route to produce 1,6-HDO from fossil fuels, were used. Heat networks are also designed to reduce operating costs and indirect carbon emissions due to energy consumption, saving 87% and 83% of the heat and cooling requirements, respectively, in Strategy A. The market competitiveness of Strategy A was evaluated by determining the minimum selling price through techno-economic analysis, and sustainability was thoroughly investigated by quantifying the environmental impacts through both midpoint and endpoint life-cycle assessments（lCAs）.Strategy A was found to be the most favorable both economically（USRDSCHARDOllAR3,402/ton） and environmentally（-26.9 kg CO2eq.）. This indicates that lignin valorization is not only economically but also environmentally preferred. Finally, changes in economic and environmental feasibilities depending on economic, process, and environmental parameters were investigated using sensitivity and uncertainty analyses. The results of these analyses provide valuable insight into bio-based chemical production.

关键词： Carbon capture and utilization

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