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Nutrient changes in potting mix and Eucalyptus nitens leaf tissue under macadamia biochar amendments 被引量:19
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作者 A.Wrobel-Tobiszewska M.Boersma +5 位作者 J.Sargison P.Adams b.singh S.Franks C.J.Birch D.C.Close 《Journal of Forestry Research》 SCIE CAS CSCD 2018年第2期379-389,共11页
The effect of macadamia nut shell biochar on nitrogen,potassium,phosphorus,magnesium,calcium and sodium concentrations in potting mix used to grow Eucalyptus nitens seedlings was investigated in a glasshouse experimen... The effect of macadamia nut shell biochar on nitrogen,potassium,phosphorus,magnesium,calcium and sodium concentrations in potting mix used to grow Eucalyptus nitens seedlings was investigated in a glasshouse experiment.The treatments combined two fertiliser rates(50 and 100% rate of the commercial mix commonly used in forestry nurseries) with eight biochar rates(0,2,5,10,20,50,80 and 100 t ha;) arranged in a randomised complete block with three replicates of four sample plants.Nutrients were quantified in the potting mix and seedling leaves at four destructive harvests 135,177,219 and269 days after planting.Biochar significantly increased nitrate-N,Colwell P,Colwell K and exchangeable Na andreduced ammonium-N,Mg and Ca concentrations in the potting mix.Seedling leaf concentrations of P,K and Na were increased by biochar application,while N remained dependent on fertiliser rate only.Mg and Ca leaf concentrations decreased in response to increasing biochar rates.Elevated nitrate-N and decreased ammonium-N concentrations suggest that biochar might have increased nitrification in the potting mix.We presumed that biochar mediated processes that reduced uptake of P and K when high doses of biochar were combined with full fertilisation.Changes in potting mix K,Na,Mg and Ca were consistent with selective adsorption of ions to biochar surfaces. 展开更多
关键词 Charcoal Forest plantation Plant nutrition SEEDLINGS Soil chemistry
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Lead Induced Oxidative Stress: Beneficial Effects of Kombucha Tea 被引量:7
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作者 P.DIPTI B.YOGESH +7 位作者 A.K.KAIN T.PAULINE B.ANJU M.SAIRAM b.singh S.S.MONGIA G.ILAVAZHAGAN DEVENDRA KUMAR W.SELVAMURTHY 《Biomedical and Environmental Sciences》 SCIE CAS CSCD 2003年第3期276-282,共7页
Objective To evaluate the effect of oral administration of Kombucha tea (K-tea) on lead induced oxidative stress. Methods Sprague Dawley rats were administered 1 mL of 3.8% lead acetate solution daily alone or in comb... Objective To evaluate the effect of oral administration of Kombucha tea (K-tea) on lead induced oxidative stress. Methods Sprague Dawley rats were administered 1 mL of 3.8% lead acetate solution daily alone or in combination with K-tea orally for 45 d, and the antioxidant status and lipid peroxidation were evaluated. Results Oral administration of lead acetate to rats enhanced lipid peroxidation and release of creatine phosphokinase and decreased levels of reduced glutathione (GSH) and antioxidant enzymes (superoxide dismutase, SOD and glutathione peroxidase, GPx). Lead treatment did not alter humoral immunity, but inhibited DTH response when compared to the control. Lead administration also increased DNA fragmentation in liver. Oral administration of Kombucha tea to rats exposed to lead decreased lipid peroxidation and DNA damage with a concomitant increase in the reduced glutathione level and GPx activity. Kombucha tea supplementation relieved the lead induced immunosuppression to appreciable levels. Conclusion The results suggest that K-tea has potent antioxidant and immunomodulating properties. 展开更多
关键词 LEAD Oxidative stress Kombucha tea Antioxidant activity
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确定尼泊尔地震震前电磁前兆的多种实验方法
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作者 S.Sharma R.P.Singh +5 位作者 D.Pundhir b.singh 孙春仙(译) 叶学(译) 许炳(译) 沈红会(校) 《世界地震译丛》 2020年第5期463-483,共21页
实验数据来自三种不同的技术:(i)利用钻孔天线测量的地下固定频率(VLF)电场;(ii)利用全球定位系统(GPS)接收机测量的电离层总电子含量(TEC)和(iii)SoftPAL监测的电离层下固定频率(f=19.8kHz)海军通信台站NWC发射信号的VLF振幅,分析了201... 实验数据来自三种不同的技术:(i)利用钻孔天线测量的地下固定频率(VLF)电场;(ii)利用全球定位系统(GPS)接收机测量的电离层总电子含量(TEC)和(iii)SoftPAL监测的电离层下固定频率(f=19.8kHz)海军通信台站NWC发射信号的VLF振幅,分析了2015年4月25日(M=7.8)和5月12日(M=7.3)发生的两次尼泊尔大地震。VLF电场数据和VLF发射信号数据取自印度的马图拉台站和阿格拉台站,而TEC数据取自三个互联网全球服务(IGS)台站,其中一个位于印度的勒克瑙(Lck3),其他位于中国的拉萨(Lhaz)和武汉(Wuhn)。除了武汉的台站位于2865km外,其余均在距两次地震震中800km以内。分析结果表明,VLF电场和TEC数据显示,在4月25日地震前8~15天内,在正常变化中出现了异常变化,在5月12日地震前5~7天内也出现了类似的异常。电离层VLF振幅的变化在震前4天也出现了异常。根据当时的雷电和磁扰因素对这些异常进行了严格的检查。然而,这些因素并不影响观测数据。文中简述了孕震辐射的产生和传播机制。 展开更多
关键词 尼泊尔地震 地震震中 尼泊尔大地震 磁扰 天线测量 数据显示 阿格拉 传播机制
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乌塔尔卡希地震的氡记录
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作者 H.S.Virk b.singh 吕春来 《世界地震译丛》 北大核心 1995年第4期84-87,共4页
用两种不同的方法(径迹蚀刻法和射气测量法)可记录到土壤气体和地下水中氡的时空分布。根据喜马拉雅山脉地震规划,在阿姆利则的一个地方和坎格拉谷(喜马偕尔邦)的4个地方建立了氡观测台站。用径迹蚀刻法测得氡一周或两周的累积量,而射... 用两种不同的方法(径迹蚀刻法和射气测量法)可记录到土壤气体和地下水中氡的时空分布。根据喜马拉雅山脉地震规划,在阿姆利则的一个地方和坎格拉谷(喜马偕尔邦)的4个地方建立了氡观测台站。用径迹蚀刻法测得氡一周或两周的累积量,而射气测量法可用于土壤和地下水中每天氡活动性的测量。乌塔尔卡希地震(m_b=6.5,M_s=7.0)于1991年10月20日(世界时10月19日)发生在位于喜马拉雅山的加瓦尔(30.78°N,78.77°E),距坎格拉谷和阿姆利则我们的记录台站分别约330km和450km。在乌塔尔卡希地震前约一周,坎格拉谷和阿姆利则全部测点都记录到了氡异常,这显然确证了氡的变化对预报某些地震是有效的。 展开更多
关键词 地震 记录 地震预报 乌塔尔卡希地震
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Nature of the Crust Below the Achankovil Shear Zone,India Based on Gravity Data
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作者 Niraj Kumar A.P.Singh b.singh 《地学前缘》 EI CAS CSCD 北大核心 2009年第S1期200-201,共2页
Evolutionary history of continents and supercontinents, and their implications on solid earth processes, require an understanding of the growth of the continental crust through time and space.Suture zones are the remn... Evolutionary history of continents and supercontinents, and their implications on solid earth processes, require an understanding of the growth of the continental crust through time and space.Suture zones are the remnant regions inherited by Proterozoic tectonics between amalgamated terranes and the long-lived shear systems are commonly assumed to represent such boundaries.One such often debated is the 展开更多
关键词 SOUTHERN GRANULITE TERRANE Achankovil shear zone TERRANE boundary gravity ANOMALY intracratonic litho-tectonic feature
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Influence of magnetic field on wave propagation at liquid-microstretch solid interface
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作者 b.singh 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI 2011年第5期595-602,共8页
The reflection and refraction of a longitudinal wave at an interface between a perfectly conducting nonviscous liquid half-space and a perfectly conducting microstretch elastic solid half-space are studied. The approp... The reflection and refraction of a longitudinal wave at an interface between a perfectly conducting nonviscous liquid half-space and a perfectly conducting microstretch elastic solid half-space are studied. The appropriate solutions to the governing equations are obtained in both the half-spaces satisfying the required boundary conditions at the interface to obtain a system of five non-homogeneous equations in the amplitude ratios of various reflected and transmitted waves. The system is solved by a Fortran program of the Gauss elimination method for a particular example of an interface between water and aluminum-epoxy composite. Numerical values of the amplitude ratios are computed for a certain range of the incidence angle both in the presence and absence of an impressed transverse magnetic field. The effects of the presence of the transverse magnetic field on the amplitude ratios of various reflected and transmitted waves are shown graphically. 展开更多
关键词 MICROSTRETCH wave propagation reflection and transmission magnetic field
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用于补偿不平衡非线性负载的三相有源滤波器新控制算法的DSP实现
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作者 b.singh 赵俊莉 《变流技术与电力牵引》 2001年第2期22-26,33,共6页
论述一种用于消除谐波,补偿无功功率,均衡不平衡非线性负荷的三相有源滤波器(简称AF)的新控制算法。AF是采用绝缘门控双极性晶体管(即IGBT)、以脉宽调制(PWM)控制电流、并带有直流电容器的电压型逆变器(VSI)。用滑动模式调节的控制器(S... 论述一种用于消除谐波,补偿无功功率,均衡不平衡非线性负荷的三相有源滤波器(简称AF)的新控制算法。AF是采用绝缘门控双极性晶体管(即IGBT)、以脉宽调制(PWM)控制电流、并带有直流电容器的电压型逆变器(VSI)。用滑动模式调节的控制器(SMC)通过AF的直流电压得到的电源电流指令与电源电压相位相同。用数字信号处理器(即DSP)来实现AF的控制算法。通过电源电流指令和实测电源电流实现间接的PWM电流控制,产生出AF的IGBT的开关控制信号。文章还给出了所述AF的试验结果,该结果显示了AF消除谐波,补偿无功功率和均衡负荷的能力。 展开更多
关键词 有源滤波器 补偿 控制算法 性能 试验
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