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Journal of Environmental Sciences 2001年第4期13卷 406-410页

作者： Fan, CX Zhang, L Qu, tc Chinese Acad Sci Nanjing Inst Geog & Limnol Nanjing 210008 Peoples R China

Intact sediment cores and wet/dried surficial sediments sampled from the two sublakes in Taihu Lake, Meiliang Bay and Wuli Lake, were incubated in the laboratory to determine the effects of resuspension on internal phosphorus loading by simulating different resuspension events. Soluble reactive phosphorus (SRP) release from undisturbed core sediment sampled in the Meiliang Bay and Wuli Lake in July 1998 was 1.53 mg/m(2) and 2.24 mg/m(2) within 4 days, respectively. However during one hour experimental simulation of resuspension, SRP increased by 0.041 mg/L and 0.077 mg/L in die above cores, which indicate that a typical resuspension event in the take would be accompanied by the release of 10.77 mgSRP/m(2) and 23.1 mgSRP/m(2), respectively. The internal phosphorus loading induced by resuspensian is estimated to be 8 - 10 times greater than the release from undisturbed sediment. SRP release from the dried sediments during simulation of resuspension was mainly dependent on the disturbing intensity. Only when the wind strength gets to certain level, the influence of wind speed on phosphorus release appears significant, indicating that an exchangeable P pool, capable of altering equilibrium conditions in the take areas, is built up under strongly wind-exposed resuspension events.

关键词： sediment resuspension simulation phosphate release Taihu Lake

AN ANALYSIS OF THE EFFECTS OF SYMMETRICAL TILT GRAIN BOUNDARIES ON THE PLASTIC DEFORMATION

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Acta Mechanica Solida Sinica 1995年第2期8卷 95-109页

作者： ZHANG, YW WANG, tc CHINESE ACAD SCI INST MECHLNMBEIJING 100080PEOPLES R CHINA

A numerical investigation on the simple polycrystals containing three symmetrical tilt grain boundaries (GBs) is carried out within the framework of crystal plasticity which precisely considers the finite deformation and finite lattice rotation as well as elastic anisotropy. The calculated results show that the slip geometry and the redistribution of stresses arising from the anisotropy and boundary constraint play an important role in the plastic deformation in the simple polycrystals. The stress level along GB is sensitive to the load level and misorientation, and the stresses along QB are distributed nonuniformly. The GB may exhibit a softening or strengthening feature, which depends on the misorientation angle. The localized deformation bands usually develop accompanying the GB plastic deformation, the impingement of the localized band on the GB may result in another localized deformation band. The yield stresses with different misorientation angles are favorably compared with the experimental results.

关键词： SIMPLE POLYCRYSTAL GRAIN BOUNDARY

NON-POLLUTION PROCESS FOR COMPLEX REFRACTORY SILVER-GOLD ORES

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中国有色金属学会会刊：英文版 1995年第4期5卷 69-72,83页

作者： Xu, SM Zhang, CF Zhao, tc Li, ZG CENT S UNIV TECHNOL DEPT NONFERROUS METCHANGSHA 410083PEOPLES R CHINA

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关键词： complex ore carbonaceous substances silver-gold concentratem lime roasting

A FINITE DEFORMATION ANALYSIS OF POLYCRYSTAL BY CONSIDERING THE INFLUENCE OF GRAIN BOUNDARY

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Acta Mechanica Solida Sinica 1996年第3期9卷 189-200页

作者： Pan, WK Zhang, YW Wang, tc UNIV SCI & TECHNOL CHINA HEFEI 230026PEOPLES R CHINA CHINESE ACAD SCI INST MECHBEIJING 100080PEOPLES R CHINA

By combining grain boundary (GB) and its influence zone, a micromechanic model for polycrystal is established for considering the influence of GB. By using the crystal plasticity theory and the finite element method for finite deformation, numerical simulation is carried out by the model. Calculated results display the microscopic characteristic of deformation fields of grains and are in qualitative agreement with experimental results.

关键词： grain boundary slip slid crystal plasticity finite deformation

Evaluation of the anticonvulsant and muscle relaxant effects of the methanol root bark extracts of Annona senegalensis

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Asian Pacific Journal of Tropical Medicine 2010年第1期3卷 25-28页

作者： Okoye tc Akah PA Omeke CP Department of Pharmacology and Toxicology Faculty of Pharmaceutical SciencesUniversity of Nigeria

Objective:To investigate the potentials of the root bark of Annona（A.） senegalensis in the control of seizure and related hypnotic and motor incoordination effects in mice using experimental ***:The methanol extract（ME） of the root bark of *** was studied in mice using pentylenetetrazole（PTZ） induced convulsions,phenobarbitone induced sleeping time and motor coordination test on rota-rod *** toxicity and lethality（LD50） lest as well as phytochemical analysis were also carried ***:The extract（200,400,800 mg/ kg） exhibited a non- dose dependent significant（P50 of 1 2%mg/kg,while the phytochemical studies showed the presence of alkaloids, resins,glycosides,carbohydrate,reducing sugar,flavonoids,terpenoids,saponins and tannins. Conclusion:The extract of A senegalensis possessed anticonvulsant activity with pronounced hypnotic and muscle relaxant effects.

关键词： Annona senegalensis Hypnosis Anticonvulsant Muscle relaxant

Antimicrobial and antispasmodic activity of leaf extract and fractions of Stachytarpheta cayennensis

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Asian Pacific Journal of Tropical Medicine 2010年第3期3卷 189-192页

作者： Okoye tc Akah PA Okoli CO Ezike AC Mbaoji FN Department of Pharmacology & Toxicology Faculty of Pharmaceutical SciencesUniversity of Nigeria

Objective:To investigate the antimicrobial activity of the methanol leaf extract(ME),n-hexane fraction(HF),ethylacetate fraction(EF) and methanol fraction(MF),of Stachytarpheta cayennensis ***(verbenaceae) as well as to ascertain the antispasmodic effects of the ME and the various fractions(HF,EF and MF) on acetylcholine(Ach) and histamine(H) induced contractions on isolated guinea pig ***:The in vitro agar well diffusion method was used for the antimicrobial studies while the isolated tissue method was employed for the antispasmodic test. Organisms used were all clinical isolates of Bacillus subtilis,Staphylococcus aureus,Pseudomonas aeruginosa,Salmonella paratyphi,Candida albicans and Aspergillus ***:The extract and fractions exhibited dose dependent inhibition against all the bacteria tested and also exhibited insignificant antifungal activity against Candida albicans and Aspergillus *** minimum inhibitory concentration(MIC) of the extract and fractions(mg/mL) on Bacillus subtilis, Staphylococcus aureus,Pseudomonas aeruginosa and Salmonella paratyphi respectively were ME 5.62,14.12,22.38,2.11;EF 1.25,6.30,9.40,9.40 and MF 3.98,8.81,39.80,*** n-hexane fraction exhibited MIC of 1.07 mg/mL against only Bacillus *** extract and fractions exhibited significant(P< 0.05) dose dependent attenuation of contractions induced by acetylcholine and histamine on isolated guinea pig *** of the extract and fractions(μg/mL) which evoked 50%inhibition of maximal response exhibited by Ach were ME 0.64,HF 0.16,EF 0.08 and MF 0.15,while that of histamine included ME 5.12,HF 0.16,EF 0.04 and MF *** phytochemical studies on the extract and fractions indicated the presence of carbohydrates,alkaloids,saponins,flavonoids,steroids and ***: The extract and fractions of Stachytarpheta cayennensis possessed both antibacterial and antispasmodic effects confirming the claimed use in folkloric medicine

关键词： Antimicrobial Antispasmodic Stachytarpheta cayennensis Acetylcholine Histamine

Magnesium lithospermate B possesses inhibitory activity on Na+,K+-ATPase and neuroprotective effects against ischemic stroke

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Acta Pharmacologica Sinica 2007年第5期28卷 609-615页

作者： Jason tc TZEN Tzyy-rong JINN Hank KH SHE Balance CM CHEN Vic HSIEH Graduate Institute of Biotechnology Herbal Source Biotechnology Co Tainan CountyTaiwan741 China Jason Life Tech Inc National Chung Hsing UniversityTaichungTaiwan 402 China

Aim:To examine if magnesium lithospermate B （MLB） extracted from Danshen,thedried roots of Salvia miltiorrhiza,may act as an active component responsible forthe cardiac therapeutic effect of this traditional Chinese herb via the same molecu-lar mechanism triggered by cardiac glycosides,such as ouabain and ***,we wanted to test if MLB may provide neuroprotection againstischemic stroke as observed for cardiac ***:Similarity in thechemical structure and molecular configuration between MLB and ouabain *** inhibition potency of MLB and ouabain on Na+,K+-ATPase activ-ity of a commercial product,as well as in purified membrane fractions from rat brainand heart tissues,was examined and *** effect of MLBagainst ischemic stroke was also evaluated using a cortical brain slice-basedassay ***:Dose-dependent inhibition on the commercial Na+,K+-ATPase equivalent to that for ouabain was observed for MLB of approximatelyhalf dosage by *** relative potency of ouabain and MLB was alsoobserved for their inhibition on Na+,K+-ATPase activity of plasma membranepurified from rat tissues,although these 2 inhibitors exhibited somewhat lowercompetence in these crude *** ischemic gerbil brains,post-treatment withMLB significantly reduced the infarct size,visualized by 2,3,5-triphenyltetrazoliumchloride staining,by approximately 55% when compared with the control ***:These results evidently suggest that the cardiac therapeutic effect ofDanshen should be at least partly attributed to the effective inhibition of Na+,K+-ATPase by MLB,and that MLB provides anti-ischemic neuroprotection in gerbilssubjected to focal ischemia and reperfusion.

关键词： cardiac glycosides magnesium lithospermate B Na~+,K~+-ATPase neuroprotection ouabain Salvia miltiorrhiza

tc Electronic数字效果器及其应用

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电声技术 2004年第8期 74-75页

作者：丹麦tc电子有限公司丹麦tc电子有限公司

1 引言随着数字音频处理技术的发展,数字效果器已被广泛应用。而且由于DSP硬件和各种精确的声音算法技术不断提高,数字效果器越来越完善,也越来越经济,甚至很多高档数字处理技术也被应用于低价位的数字效果器中。

关键词：效果器声场 tc Electronic 立体声

Effect of tcA-depletion of extrinsic polypeptides on electron transport on oxidizing side of PS II

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Chinese Science Bulletin 1997年第3期42卷 227-231页

作者： Li, R Shen, YG Xu, CH Lu, W Tu, tc Yao, S Lin, NY Shanghai Institute of Plant Physiology Chinese Academy of Sciences Shanghai China Shanghai Institute of Technical Physics Chinese Academy of Sciences Shanghai China Shanghai Institute of Nuclear Research Chinese Academy of Sciences Shanghai China

PHOTOSYSTEM Ⅱ （PS Ⅱ） particles capable of O2 evolution contain reaction center polypeptides D1 and D2, cytchrome b559, chlorophyll （Chl）-binding proteins CP47 and CP43, three extrinsic polypeptides （with apparent molecular masses of 17, 23 and 33 ku） and cofactors needed for light energy conversion. After illumination, PS Ⅱ oxygen evolution complex （OEC） catalyzes the oxidization of water to molecular oxygen through S0→S4 redox state transition. The three extrinsic polypeptides have been revealed to be closely related to the photosynthetic O2 evolution.

关键词： PSⅡ extrinsic polypeptide trichloroacetate (tcA-NaOH) FTIR EPR signal Ⅱ.