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journal of Environmental Sciences 1999年第4期11卷 449-456页

作者： M.M.Muniafu j.N.M.Macharia C.j.Stigter G.L.Coulson Department of Botany University of NairobiNairobiKenya TTMI-Project Department of MeteorologyWageningen Agricultural UniversityDuivendaal 26701 AP WageningenNetherlands T TMI-Project Departmen t of BotanyUniversi ty of Nai robiKenya

Leaf area development, dry weight accumulation and solar energy conversion efficiencies of Phaseolus vulgaris L. cv GLP\|2 under two soil moisture levels in two contrasting seasons near Nairobi, Kenya were investigated. The experiment confirms that dry weights and yields of Phaseolus vulgaris are limited by a drought induced decrease in leaf area, leading to less radiation interception as a source for assimilation. However, photosynthetic efficiency in Phaseolus vulgaris also appears to decrease and to contribute to these effects. Finally, an even larger decreases of economic efficiency as obtained in the second season, where stress lasted much later into the season, reveals that such a drought also limits considerably the partitioning and translocation of assimilates to the seeds of Phaseolus vulgaris. The efficiencies obtained are in line with the better literature data for other crops.

关键词： economic efficiency Phaseolus vulgaris L. photosynthetic efficiency radiation absorption/interception tube solarimeters

Temperature-controlled mode selection of Er-doped random fiber laser with disordered Bragg gratings

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Photonics Research 2016年第3期4卷 102-105页

作者： W.L.Zhang Y.B.Song X.P.Zeng R.Ma Z.j.Yang Y.j.Rao Key Laboratory of Optical Fiber Sensing & Communications (Education Ministry of China) University of Electronic Science & Technology of China

In this paper, we proposed a way to realize an Er-doped random fiber laser(RFL) with a disordered fiber Bragg grating(FBG) array, as well as to control the lasing mode of the RFL by heating specific locations of the disordered FBG array. The disordered FBG array performs as both the gain medium and random distributed reflectors, which together with a tunable point reflector form the RFL. Coherent multi-mode random lasing is obtained with a threshold of between 7.5 and 10 mW and a power efficiency between 23% and 27% when the reflectivity of the point reflector changes from 4% to 50%. To control the lasing mode of random emission, a specific point of the disordered FBG array is heated so as to shift the wavelength of the FBG(s) at this point away from the other ***, different resonance cavities are formed, and the lasing mode can be controlled by changing the location of the heating point.

关键词： mode Temperature-controlled mode selection of Er-doped random fiber laser with disordered Bragg gratings

CO和H2在沉淀铁催化剂上的化学吸附和程序升温脱附

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燃料化学学报 1988年第3期 284-288页

作者：赵玉龙 anderson R.R. Gormley R.j. Rao V.U.S. 中国科学院山西煤炭化学研究所 Pittsburgh Energy Technology Center Pittsburgh Energy Technology Center 太原 U.S.A.

铁催化剂是一种重要的F-T 合成催化剂。本文的目的是通过CO 和H2在浆态相F-T合成采用的无载体沉淀铁催化剂上的化学吸附和程序升温脱附（TPD）的实验结果,考察钾的加入对催化剂性能的影响。实验采用共沉淀法制备的Fe-Cu（Fe65w%;Cu 0.6... 详细信息

铁催化剂是一种重要的F-T 合成催化剂。本文的目的是通过CO 和H2在浆态相F-T合成采用的无载体沉淀铁催化剂上的化学吸附和程序升温脱附（TPD）的实验结果,考察钾的加入对催化剂性能的影响。实验采用共沉淀法制备的Fe-Cu（Fe65w%;Cu 0.6w%,其余为平衡氧）和Fe-Cu-K（Fe,Cu 含量同上,K0.1w%,其余为平衡氧）两种催化剂。程序升温脱附实验在装有四极质谱仪的吸附-解吸系统内进行。化学吸附用Chemisorb 2800装置测

关键词：催化剂活性吸附 H2 程序升温脱附 CO 化学吸附 TPD

The parallel-plate resonator:An RF probe for MR and MRI studies over a wide frequency range

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Magnetic Resonance Letters 2023年第4期3卷 306-318页

作者： Andres Ramírez Aguilera Kevin j.Sanders Gillian R.Goward Bruce *** UNB MRI Centre Department of PhysicsUniversity of New BrunswickFrederictonNew BrunswickE3B 5A3Canada Department of Chemistry McMaster UniversityHamiltonOntarioL8S 4L8Canada

We explore the use of the parallel-plate resonator for the study of thin cuboid samples over a wide range of magnetic resonance *** parallel-plate resonator functions at frequencies from tens to hundreds of *** parallel-plate resonators are presented and discussed in a frequency range from 8 to 500 *** resonance experiments were performed on both horizontal and vertical bore magnet systems with lithium and hydrogen ***-plate radiofrequency(RF)probes are easy to build and easy to *** and simulations showed good sensitivity of the parallel-plate RF probe geometry with a small decrease in sensitivity at higher frequencies.

关键词： Parallel-plate resonator Optimization Magnetic resonance/magnetic resonance imaging(MR/MRI) Batteries

EFFECTS OF Pb COMPOUND ADDITIVES ON THE PROPERTIES OF YBa_2Cu_3O_(7-δ)

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Acta Metallurgica Sinica(English Letters) 2005年第2期18卷 145-148页

作者： F.H.Li Z.G.Fan j.Wang C.S.Liu D.W.Soh Y.j.Cho SchoolofMaterialandMetallurgy NortheasternUniversityShenyang110004China MyongjiUniversity Yongjin449-728SouthKorea

The melting temperature and critical transition temperature Tc of YBa2Cu3O7-δ with deferent content additives of PbO and BaPbO3 were studied. When PbO was doped in YBa2Cu3O7-δ, the melting temperature of YBa2Cu3O7-δ was reduced, however its superconductivity was weakened. From the XRD pattern of the sintered mixture of YBa2Cu3O7-δ and PbO, it was known that there was a reaction between YBa2Cu3O7-δ and PbO, and the product was BaPbO3. Hence different contents of BaPbO3 (10mass%, 20mass% and 30mass%) were added in YBa2Cu3O7-δ. It was proved that there were no reactions between YBa2Cu3O7-δ and BaPbO3. And the superconductivity of the mixtures was much better than that of the samples with PbO additive.

关键词： YBa2Cu3O7-δ PbO additive melting temperature superconductivity

Understanding temporal stability:a long-term analysis of USDA ARS watersheds

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International journal of Digital Earth 2021年第10期14卷 1243-1254页

作者： Evan j.Coopersmith Michael H.Cosh Patrick j.Starks David D.Bosch Chandra Holifield Collins Mark Seyfried Stan Livingston john Prueger Soil Insight LLCWashington D.C.USA USDA-Agricultural Research Service Beltsville Agricultural Research CenterHydrology and Remote Sensing LaboratoryBeltsvilleUSA USDA-Agricultural Research Service-Grazinglands Research Laboratory El RenoUSA USDA-Agricultural Research Service-Southeast Watershed Research Laboratory TiftonUSA USDA-Agricultural Research Service-Southwest Watershed Research Center TucsonUSA USDA-Agricultural Research Service-Northwest Watershed Research Laboratory BoiseUSA USDAAgricultural Research Service-National Soil Erosion Research Laboratory West LafayetteUSA USDA-Agricultural Research Service-National Laboratory for Agriculture and Environment AmesUSA

The *** of Agriculture’s Agricultural Research Service(USDAARS)maintains seven in situ soil moisture networks throughout the continental United States,some since *** networks are crucial for understanding the spatial and temporal extent of droughts in their historical context,parameterization of hydrologic models,and local agricultural decision ***,the estimates from these networks are dependent upon their ability to provide reliable soil moisture information at a large *** is also not known how many network stations are sufficient to monitor watershed scale ***,the objectives of this research were to:(1)determine how temporally stable these networks are,including the relationships between various sensors on a year-to-year and seasonal basis,and(2)attempt to determine how many sensors are required,within a network,to approximate the full network *** data from seven in situ,it is concluded that approximately 12 soil moisture sensors are sufficient in most environments,presuming their locations are distributed to capture the hydrologic heterogeneity of the *** is possible to install a temporary network containing a suitable number of sensors for an appropriate length of time,glean stable relationships between locations,and retain these insights moving forward with fewer sensor resources.

关键词： Soil moisture temporal stability in situ networks

INFLUENCE OF SO_4^(2-) AND Cl-ON THE CORROSION BEHAVIOR OF COPPER TUBE IN AIR-CONDITIONING SYSTEM

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Acta Metallurgica Sinica(English Letters) 2004年第1期17卷 92-96页

作者： C.S.Wu Z.Zhang F.H.Cao j.Q.Zhang j.M.Wang C.N.Cao Department of Chemistry Yuquan CampusZhejiang University Hangzhou 310027ChinaDepartment of Chemistry Yuquan CampusZhejiang University Hangzhou 310027ChinaDepartment of Chemistry Yuquan CampusZhejiang University Hangzhou 310027ChinaDepartment of Chemistry Yuquan CampusZhejiang University Hangzhou 310027China State Key Laboratory for Corrosion and Protection of Metals Shenyang 110016 ChinaDepartment of ChemistryYuquan Campus Zhejiang University Hangzhou 310027ChinaDepartment of ChemistryYuquan Campus Zhejiang University Hangzhou 310027China State Key Laboratory for Corrosion and Protection of MetalsShenyang 110016 China

The influence of chloride or sulphur dioxide on the corrosion behavior of copper tube in the air-conditioning system was studied using scanning electron microscope (SEM), energy dispersion spectrometer (EDS) and cyclic polarization techniques. The results showed that the corrosion of copper tube are mainly caused by the SO42- and Cl- ions in the circulating water, and the former is mainly responsible for the general corrosion of the copper tube whilst the latter for the pitting corrosion. The different influences of SG42- and Cl- ions on the corrosion type of copper tube may be attributed to that the radius of SO42- ion is much larger than that of Cl- ion. Meanwhile the results also indicated that SO42- inhibits the pitting corrosion caused by Cl- and Cl- inhibits the general corrosion initiated by SO42- due to their competitive adsorption on the copper matrix.

关键词： copper corrosion behavior influence SO42- ion Cl- ion

Prolonged feeding with guanidinoacetate, a methyl group consumer, exacerbates ethanol-induced liver injury

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World journal of Gastroenterology 2016年第38期22卷 8497-8508页

作者： Natalia A Osna Dan Feng Murali Ganesan Priya F Maillacheruvu David j Orlicky Samuel W French Dean j Tuma Kusum K Kharbanda Research Service Veterans Affairs Nebraska-Western Iowa Health Care System Department of Internal Medicine 982000 Nebraska Medical Center Department of Pathology University of Colorado Denver Department of Anatomic Pathology Harbor UCLA Medical Center Department of Biochemistry and Molecular Biology 985870 Nebraska Medical Center

AIM To investigate the hypothesis that exposure to guanidinoacetate(GAA, a potent methyl-group consumer) either alone or combined with ethanol intake for a prolonged period of time would cause more advanced liver pathology thus identifying methylation defects as the initiator and stimulator for progressive liver *** Adult male Wistar rats were fed the control or ethanolLieber De Carli diet in the absence or presence of GAA supplementation. At the end of 6 wk of the feeding regimen, various biochemical and histological analyses were conducted. RESULTS Contrary to our expectations, we observed that GAA treatment alone resulted in a histologically normal liver without evidence of hepatosteatosis despite persistence of some abnormal biochemical parameters. This protection could result from the generation of creatine from the ingested GAA. Ethanol treatment for 6 wk exhibited changes in liver methionine metabolism and persistence of histological and biochemical defects as reported before. Further, when the rats were fed the GAA-supplemented ethanol diet, similar histological and biochemical changes as observed after 2 wk of combined treatment, including inflammation, macroand micro-vesicular steatosis and a marked decrease in the methylation index were noted. In addition, rats on the combined treatment exhibited increased liver toxicity and even early fibrotic changes in a subset of animals in this group. The worsening liver pathology could be related to the profound reduction in the hepatic methylation index, an increased accumulation of GAA and the inability of creatine generated to exert its hepato-protective effects in the setting of *** To conclude, prolonged exposure to a methyl consumer superimposed on chronic ethanol consumption causes persistent and pronounced liver damage.

关键词： Methyl balance S-adenosylmethionine S-adenosylhomocysteine Guanidinoacetate Alcohol

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作者： j.·霍(j. Hoe)

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