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Effects of Cinnamic Acid on Bacterial Community Diversity in Rhizosphere Soil of Cucumber Seedlings Under Salt Stress

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Agricultural Sciences in China 2010年第2期9卷 266-274页

作者： LIU Jing WU Feng-zhi yang yang Horticulture College Northeast Agricultural University Harbin 150030 P.R.China

To investigate the effects of a plant autotoxin, cinnamic acid, on bacterial communities in the rhizosphere soil of cucumber seedlings under salt stress, we used cucumber as the experimental material, cinnamic acid as the autotoxin, and NaCl to apply salt stress. Bacterial communities in the rhizosphere soil were analyzed using polymerase chain reaction （PCR）, denaturing gradient gel electrophoresis （DGGE）, and clone sequencing. Salt stress decreased the diversity of bacterial species in rhizosphere soil of cucumber seedlings at several growth stages. Cinnamic acid exacerbated the effects of salt stress at high concentrations, but alleviated its effects at low concentrations. Cloning and sequencing results indicated that DGGE bands amplified from soil samples showed high homology to uncultured bacterial species. Cinnamic acid at 50 mg kg^-1 soil improved cucumber growth and was the most effective treatment to alleviate the effects of salt stress on bacterial communities.

关键词： bacteria cinnamic acid cucumber salt stress PCR-DGGE

Influence of Prior Austenite Deformation and Non-Metallic Inclusions on Ferrite Formation in Low-Carbon Steels

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Journal of Iron and Steel Research International 2010年第6期17卷 36-42页

作者： ZHANG Chi XIA zhi-xin yang zhi-gang LIU zhi-hao Department of Materials Science and Engineering Tsinghua University Beijing 100084 China

Effects of prior austenite deformation and non-metallic inclusions on the ferrite nucleation and grain refine- ment of two kinds of low-carbon steels have been studied. The ferrite nucleation on MnS and V（C, N） is observed. The combination of thermomeehanical processes with adequate amounts of non-metallic inclusions formed in low-car- bon steels could effectively refine the grain size and the microstructure. Ferrite nucleated on the single MnS or V（C, N） inclusions and complex MnS＋V（C,N） inclusion. The proper addition of elements S and V could effectively promote the formation of ferrite and further refinement of ferrite grains.

关键词： austenite deformation non-metallic inclusion ferrite nucleation low-carbon steel

A 3.9ppm/℃ 8.8nW and High PSRR Subthreshold CMOS Multiple Voltage Reference

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Chinese Journal of Electronics 2017年第1期26卷 101-105页

作者： JIANG Mei LI Yongquan yang zhi College of Information Engineering Shenzhen University

A voltage reference with low Temperature coefficient（TC） and three outputs, which is compatible with high Power supply rejection ratio（PSRR） and low power consumption, is presented in this paper. The proposed reference circuit operating with all transistors biased in subthreshold region, provides three reference voltages of340 m V, 680 m V, and 1020 m V. Subthreshold MOSFET design allows the circuit to work with minimum current consumption of 7.4nA at the supply voltage 1.2V. The mean line sensitivity is 1.7%/V under a supply voltages ranging from 1.2 to 3V. The Power supply rejection ratio（PSRR）of 340 m V output voltage simulated at 100 Hz and 10 MHz is over than 51.9dB and 120.4dB, respectively. Monte Carlo simulation shows a mean TC is 3.9ppm/?C with a standard deviation of 1ppm/?C over a set of 500 samples, in a temperature range from –30?C to 100?C. The active area of the presented voltage reference is 0.003mm2.

关键词： Voltage reference Multiple output Subthreshold circuit Ultra-low power Differential threshold

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铁碳填料耦合生物膜法对生活污水的处理研究

水处理技术 2025年第1期51卷 90-96,113页

作者：任珺武潮辉杨埴王若安杨莉萍陶玲兰州交通大学环境与市政工程学院甘肃兰州730070 甘肃瀚兴环保科技有限公司甘肃兰州730070 甘肃创恒环保工程有限公司甘肃兰州730070

在700~1000℃的高温下烧结制备了不同种类的铁碳微电解填料,通过静态实验表明,掺杂铝粉的铁碳微电解填料投加到生活污水中有显著的处理效果,NH_(4)^(+)-N、COD和TN分别达到了6.18%、44.18%和6.86%,去除效果优于其他填料。掺杂铝粉的铁... 详细信息

在700~1000℃的高温下烧结制备了不同种类的铁碳微电解填料,通过静态实验表明,掺杂铝粉的铁碳微电解填料投加到生活污水中有显著的处理效果,NH_(4)^(+)-N、COD和TN分别达到了6.18%、44.18%和6.86%,去除效果优于其他填料。掺杂铝粉的铁碳填料在TP的去除率为33.45%,低于掺杂碳酸镁的铁碳微电解填料35.53%的去除率。但是,根据综合处理效果来看,处理生活污水最佳的填料为掺杂铝粉的铁碳微电解填料。将掺杂铝粉的铁碳微电解填料投加到挂膜成功的生物膜反应器中,结果表明,投加铁碳微电解填料的生物膜在NH_(4)^(+)-N、COD、TN和TP的平均出水去除率分别达到了85%、89%、79%和81%。

关键词：生活污水生物膜铁碳微电解填料

Study of semileptonic decay of Bs^-0→φI^+I^- in QCD sum rule

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Communications in Theoretical Physics 2020年第9期72卷 58-69页

作者： Ying-Quan Peng Mao-zhi yang School of Physics Nankai UniversityTianjin 300071China

In this work we study the semileptonic decay of Bs^-0→φI^+I^-(l=e,μ,τ) with the QCD sum rule method. We calculate the Bs^-0→φ ftranslation form factors relevant to this semileptonic decay, then the branching ratios of Bs^-0→φI^+I^-(l=e,μ,τ)decays are calculated with the form factors obtained here. Our result for the branching ratio of Bs^-0→φμ^+μ^- agree very well with the recent experimental data. For the unmeasured decay modes such as Bs^-0→φe^+e^- and Bs^-0→τ^+τ……-, we give theoretical predictions.

关键词： semileptonic decay form factor QCD sum rule

Kinetics and mechanism of the adsorption of methylene blue onto ACFs

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Journal of China University of Mining and Technology 2008年第3期18卷 437-440页

作者： yang zhi-yuan Department of Chemistry ＆ Chemical Engineering Xi ＇an University of Science and Technology Xi＇an Shaanxi 710054 China Geology Institute Xi＇ an Branch of China Coal Research Institute Xi＇ an Shaanxi 710054 China

The kinetics and mechanism of methylene blue (MB) adsorption onto activated carbon fibers (ACFs) have been studied. The effects of various experimental parameters, such as the initial MB concentration and the ACF mass, on the adsorption rate were investigated. Equilibrium data were fit well by a Freundlich isotherm equation. Adsorption measurements show that the process is very fast. The adsorption data were modeled using first- and second-order kinetic equations and intra–particle diffusion models. It was found that the first-order kinetic equation could best describe the adsorption kinetics. The adsorption process was found to be complex and controlled by both surface and pore diffusion with surface diffusion at the earlier stages, followed by pore diffusion at the later stages. The thermodynamic parameters △G0, △S0 and △H0, have been calculated. The thermodynamics of the MB-ACF system indicate that the adsorption process is spontaneous.

关键词： sorption ACFs methylene blue equilibrium mechanism

Late-model Ionic Clusters of KNO_3 and Their Configurations

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Chemical Research in Chinese Universities 2005年第5期21卷 587-591页

作者： SHI Lei yang zhi LIU zhi-qiang LIU Shu-ying School of Public Health Jilin University Changchun 130021 P. R. China Changchun Institute of Applied Chemistry Chinese Academy of Sciences Changchun 130022 P. R. China

Late-model ionic clusters of KNO3 were formed under the conditions of electrospray ionization. A series of peaks of the ionic clusters could be observed in the electrospray ionization mass spectra（ESIMS）. The general formulae of the ionic clusters were deduced to be K^ ＋（ KNO3 ） m and NO3^-（ KNO3 ）m. By referring to the crystal structure of KNOs , the possible configurations of these new typical ionic clusters were speculated based on the calculated data by means of the Gaussian-94^x computer program.

关键词： Cluster KNO3 Configuration Gaussian-94^* computer program

PHOTO-INDUCED GRAFT POLYMERIZATION OF ACRYLAMIDE ON POLYPROPYLENE MEMBRANE SURFACE IN THE PRESENCE OF DIBENZYL TRITHIOCARBONATE

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Chinese Journal of Polymer Science 2007年第2期25卷 221-226页

作者： Qian yang Jing Tian zhi-kang Xu Institute of Polymer Science and Key Laboratory of Macromolecule Synthesis and Functionalization （Ministry of Education） Zhejiang University Hangzhou 310027 China

Ultraviolet （UV）-induced graft polymerization of acrylamide （AAm） on polypropylene substrates was successfully conducted using dibenzyl trithiocarbonate （DBTTC） as photoinitiator. It was confirmed by chemical analysis and surface morphology observation with attenuated total reflectance Fourier transform infrared spectroscopy, X-ray photoelectron spectroscopy, and scanning electron microscopy. A possible mechanism for this graft process was presented, which suggested that, under UV irradiation, the C： S bond in DBTTC could split and abstract a hydrogen from the polypropylene surface and a surface free radical was then formed, and initiated the graft polymerization of AAm.

关键词： Graft polymerization Surface modification Acrylamide Trithiocarbonate UV.

Catalytic Preparation of Methyl Formate from Methanol over Silver

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Chemical Research in Chinese Universities 2005年第5期21卷 573-576页

作者： yang zhi LI Jing yang Xiang-guang WU Yue Changchun Institute of Applied Chemistry Chinese Academy of Sciences Changchun 130022 P. R. China Graduate School Chinese Academy of Sciences Belting 100039 P. R. China

A catalytic reaction over a silver catalyst performed in an unregarded temperature region（473-873 K） with a long catalytic lifetime for the production of methyl formate from methanol was provided as a potential preparing route. The optimal yield of methyl formate（ca. 14. 8% ） with a selectivity 〉90% was obtained at about 573 K. Because α- oxygen species and bulk oxygen species coexist in the unregarded temperature region, a synergistic process concerning α-oxygen species and bulk oxygen species was proved over Oα -rich and Oγ-rich samples.

关键词： Silver Methanol Methyl formate Oxygen species Svnergistic effect