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Phosphorus status and microbial community of paddy soil with the growth of annual ryegrass (Lolium multiflorum Lam.) under different phosphorus fertilizer treatments

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Journal of Zhejiang University-Science B(Biomedicine & Biotechnology) 2009年第10期10卷 761-768页

作者： Hai-chao guo Guang-huo WANG Department of Resource Science College of Environmental and Resource Sciences Zhejiang University Hangzhou 310029 China

Annual ryegrass （Lolium multiflorum Lam.） was grown in paddy soil in pots under different phosphorus （P） fertilizer treatments to investigate changes of P fractions and microbial community of the soil. The treatments included Kunyang phosphate rock （KPR） applications at 50 mg P/kg （KPRs0） and 250 mg P/kg （KPR250）, mono-calcium phosphate （MCP） application at 50 mg P/kg （MCP50）, and the control without P application. The results showed that KPR50, KPR250, and MCP50 applications significantly increased the dry weight of the ryegrass by 13%, 38%, and 55%, and increased P uptake by 19%, 135%, and 324%, respectively. Compared with MCP50, the relative effectiveness of KPR50 and KPR250 treatments in ryegrass production was about 23% and 68%, respectively. After one season ofryegrass growth, the KPR50, KPR250, and MCP50 applications increased soil-available P by 13.4%, 26.8%, and 55.2%, respectively. More than 80% of the applied KPR-P remained as HC1-P fraction in the soil. Phospholipid fatty acid （PLfa） analysis showed that the total and bacterial PLfas were significantly higher in the soils with KPR250 and MCP50 treatments compared with KPR50 and control. The latter had no significant difference in the total or bacterial PLfas. The KPR50, KPR250, and MCP50 treatments increased fungal PLfa by 69%, 103%, and 69%, respectively. Both the principal component analysis and the cluster analysis of the PLfa data suggest that P treatments altered the microbial community composition of the soils, and that P availability might be an important contributor to the changes in the microbial community structure during the ryegrass growth in the paddy soils.

关键词： Phosphorus fractionation Phospholipid fatty acid (PLfa) Ryegrass Phosphate rock

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A low-voltage sense amplifier with two-stage operational amplifier clamping for flash memory

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Journal of Semiconductors 2017年第4期38卷 83-87页

作者： Jiarong guo School of Electronics and Information Shanghai Dianji UniversityShanghai 200240China

A low-voltage sense amplifier with reference current generator utilizing two-stage operational amplifier clamp structure for flash memory is presented in this paper,capable of operating with minimum supply voltage at1 V.A new reference current generation circuit composed of a reference cell and a two-stage operational amplifier clamping the drain pole of the reference cell is used to generate the reference current,which avoids the threshold limitation caused by current mirror transistor in the traditional sense amplifier.A novel reference voltage generation circuit using dummy bit-line structure without pull-down current is also adopted,which not only improves the sense window enhancing read precision but also saves power *** sense amplifier was implemented in a flash realized in 90 run flash *** results show the access time is 14.7 ns with power supply of 1.2 V and slow corner at 125℃.

关键词： flash memory sense amplifier low voltage two-stage operational amplifier current sensing

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Theoretical design of thermal spin molecular logic gates by using a combinational molecular junction

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Chinese Physics B 2022年第4期31卷 616-621页

作者： Yi guo Peng Zhao Gang Chen School of Physics and Technology University of JinanJinan 250022China School of Physics and Electronics Shandong Normal UniversityJinan 250358China

Based on the density functional theory combined with the nonequilibrium Green function methodology,we have studied the thermally-driven spin-dependent transport properties of a combinational molecular junction consisting of a planar four-coordinate Fe molecule and a 15,16-dinitrile dihydropyrene/cyclophanediene molecule,with single-walled carbon nanotube bridge and *** results show that the magnetic field and light can effectively regulate the thermallydriven spin-dependent *** thermal spin-filtering effect and good thermal switching effect are *** results are explained by the Fermi-Dirac distribution function,the spin-resolved transmission spectra,the spatial distribution of molecular projected self-consistent Hamiltonian orbitals,and the spin-resolved current *** the basis of these thermally-driven spin-dependent transport properties,we have further designed three basic thermal spin molecular AND,OR,and NOT gates.

关键词： thermal molecular logic gate thermally-driven spin-dependent transport combinational molecular junction nonequilibrium Green's function

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Statistics of states generated by quantum-scissors device

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Chinese Physics B 2019年第3期28卷 103-108页

作者： Ming-Hao Wang guo-An Yan State Key Laboratory of Magnetic Resonances and Atomic and Molecular Physics Wuhan Institute of Physics and MathematicsChinese Academy of SciencesWuhan 430071China University of Chinese Academy of Sciences Beijing 100049China School of Physics and Technology Wuhan UniversityWuhan 430072China

Generating desired states is a prerequisite in quantum information. Some desired states can be generated by a quantum-scissors device(QSD). We present a detailed analysis of the properties of the generated states, including average photon numbers and intensity gains. The theoretical analysis shows that there is a nondeterministic amplification in terms of the average photon number under the condition that the average photon number of the input state is less than 1. In contrast to the input states, the generated states show the nonclassical property described by the negativity of the Wigner function. Furthermore, we generalize the QSD to truncate arbitrary photon number terms of the input states, which may be useful in high-dimensional quantum information processing.

关键词： quantum state generation nondeterministic amplification nonclassical property generalized quantum-scissors

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Comparing electrocatalytic hydrogen and oxygen evolution activities of first-row transition metal complexes with similar coordination environments

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Journal of Energy Chemistry 2021年第12期30卷 659-666,I0016页

作者： Xiaotong Jin Xialiang Li Haitao Lei Kai guo Bin Lv Hongbo guo Dandan Chen Wei Zhang Rui Cao Key Laboratory of Applied Surface and Colloid Chemistry Ministry of EducationSchool of Chemistry and Chemical EngineeringShaanxi Normal UniversityXi’an 710119ShaanxiChina

Developing cheap and efficient electrocatalysts for water splitting is required for energy conversion *** first-row transition metal complexes have been shown to be active for the hydrogen evolution reaction(HER)and oxygen evolution reaction(OER).Metal ions play crucial roles in these catalytic processes,but the activity dependence on the nature of metal ions has been rarely studied due to the difficulty to compare metal complexes with different coordination *** herein reported the synthesis of a series of metal complexes of azido-substituted porphyrin(1),in which metal ions have very similar coordination *** grafting 1-M(M=Mn,Fe,Co,Ni,and Cu)onto alkynefunctionalized carbon nanotubes(CNTs)through the same covalent connection,the resulted hybrids 1-M@CNT were all active and robust for both electrocatalytic HER and OER in alkaline aqueous *** these hybrids,1-Fe@CNT displayed the highest electrocatalytic activity for HER,while 1-Co@CNT was the most active one for ***,a two-electrode water electrolysis cell assembled with 1-Fe@CNT as the cathode and 1-Co@CNT as the anode required smaller applied bias potential by210 mV to get 10 mA/cm^(2)current density as compared to that assembled with Pt/C and Ir/C with the same amount of metal *** work is significant to correlate HER and OER activity with the nature of first-row transition metal ions and to highlight promising potential applications of molecular electrocatalysis in water splitting.

关键词： Metal porphyrins Molecular electrocatalysis Hydrogen evolution Oxygen evolution Water splitting

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Computing Ground State Solution of Bose-Einstein Condensates Trapped in One-Dimensional Harmonic Potential

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Communications in Theoretical Physics 2006年第5X期46卷 873-878页

作者： YUAN Qing-Xin DING guo-Hui Department of Mathematics and Physics Zhengzhou Institute of Aeronautical Industry Management Zhengzhou 450015 China Department of Physics Shanghai Jiao Tong University Shanghai 200030 China

For Bose-Einstein condensates trapped in a harmonic potential well, we present numerical results from solving the tlme-dependent nonlinear Schrolinger equation based on the Crank-Nicolson method. With this method we are able to find the ground state wave function and energy by evolving the trial initial wave function in real and imaginary time spaces, respectively. In real time space, the results are in agreement with [Phys. Rev. A 51 （1995） 4704], but the trial wave function is restricted in a very small range. On the contrary, in imaginary time space, the trial wave function can be chosen widely, moreover, the results are stable.

关键词： Bose-Einstein condensates nonlinear Schrodinger equation Crank-Nicolson method

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基于条件价值法的大熊猫(Ailuropoda melanoleuca)存在价值评估

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生态学报 2008年第5期28卷 2090-2098页

作者：宗雪崔国发袁婧北京林业大学自然保护区学院北京100083

大熊猫(Ailuropoda melanoleuca)是我国特有的国家一级保护物种,具有重要的保护意义,但其存在价值目前缺乏明确的市场价格。因此对大熊猫的存在价值进行估算,在中国乃至世界的野生动物保护中具有重要作用。通过条件价值法(contingent va... 详细信息

大熊猫(Ailuropoda melanoleuca)是我国特有的国家一级保护物种,具有重要的保护意义,但其存在价值目前缺乏明确的市场价格。因此对大熊猫的存在价值进行估算,在中国乃至世界的野生动物保护中具有重要作用。通过条件价值法(contingent valuation method,CVM),研究了我国居民对于大熊猫的保护意识和支付意愿(willingness to pay,WTP),进而对大熊猫总体存在价值进行了评估。问卷调查选择在大熊猫栖息地集中分布的四川省进行,采用支付卡式(Payment Card,PC)问卷调查方式,对回收的674份有效问卷进行统计分析。其中非零支付474份,占有效问卷的70.4%。调查表明:人均支付价值为82.7yuan/a,进而得出我国大熊猫总的存在价值为3.67×1010yuan/a。建立支付价值与居民社会经济因子的回归模型,通过AIC(Akaike′sInformation Criterion)指数选择最优模型,结果显示对支付价值有显著影响的因子为学历、收入和年龄。其中,支付价值与学历、收入水平呈正相关,与年龄呈负相关。通过对年龄、学历、收入3个因子进行方差分析,得出各因子不同水平支付价值的差异。

关键词：条件价值法支付意愿存在价值大熊猫(Ailuropoda melanoleuca)

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Does season regulate heterochronous leaf growth?Mechanisms of petiole-lamina trade-offs in broad-leaved woody plants of the Tianshan Mountains

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Plant Diversity 2024年第6期46卷 755-765页

作者： Wenjie guo Lu Gong Yan Luo Qian guo School of Ecology and Environment Xinjiang UniversityWulumuqi830017China

As the core of leaf functional traits,the trade-off relationship between the petiole and lamina expresses the plant's adaptability to the environment in terms of support structure and *** investigated the proportions of allometric growth in the relationship between the petiole and the lamina of broadleaf woody plants in temperate highland Tianshan Mountains montane forests through three dimensions(length,area,and mass),including the length of the lamina(LL)and the length of the petiole(PL),and the area of the lamina(LA)and petiole cross sectional area(PCA)versus the mass of the lamina(LM)and the mass of the petiole(PM),as well as exploring the characteristics of the variance in response to seasonal *** found that the functional traits in all three dimensions showed a clear convergent evolution as the seasons progressed,that is,a“seasonal effect”of increasing and then *** effect of the petioleelamina relationship under spring was minimal in the area dimension;the effects of the threeedimensional relationships of the traits were all highest in summer,and the effect of the petioleelamina relationship was lower in *** also found that petiole traits are simultaneously and multiply affected by lamina traits,with LA and LM having additional effects on the length/mass and area dimensions,*** to tree species,shrub species significantly require more light intensity and support ***-leaved plants would invest more in photoluminescence,increasing leaf light capture efficiency and static load and dynamic *** results suggest that plants have rather complex trade-off mechanisms at the leaf level influencing their ability to adapt to the environment,emphasize the need for leaf-level studies on the relationships between functional traits in plants,and illustrate the importance of the season as a distinct time scale for plant trade-off mechanisms.

关键词： Allometric relationship Functional traits Leaf Season

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Finite Groups with Its Power Automorphism Groups Having Small Indices

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Acta Mathematica Sinica,English Series 2009年第7期25卷 1097-1108页

作者： Jun Xin WANG Xiu Yun guo Department of Mathematics Shanxi University of Finance and Economics Taiyuan 030006 P.R. China Department of Mathematics Shanghai University Shanghai 200444 P.R.China

In this paper, a finite group G with IAut（G）： P（G）I ^- p or pq is determined, where P（G） is the power automorphism group of G, and p, q are distinct primes. Especially, we prove that a finite group G satisfies ｜Aut（G）： P（G）｜= pq if and only if Aut（G）/P（G） ≌S3. Also, some other classes of finite groups are investigated and classified, which are necessary for the proof of our main results.

关键词： power automorphism group norm action

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Effect of CeO_(2) on carbon deposition resistance of Ni/CeO_(2) catalyst supported on SiC porous ceramic for ethanol steam reforming

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Journal of Rare Earths 2023年第11期41卷 1703-1713,I0002页

作者： Tingting Bao Hui zhou Yi Zhang Chenxu guo Wenming guo Hang Qin Pengzhao Gao Hanning Xiao Weixiong Liu College of Materials Science and Engineering Hunan UniversityChangsha410082China School of Chemical Engineering Sichuan UniversityChengdu610065China

Ni/CeO_(2) catalysts(nCeO_(2):n_(Ni)=0,1,4,7,10)supported on SiC porous ce ramics for ethanol steam reforming(ESR)were investigated with respect to hydrogen production performance and growth of carbon *** oxygen released from CeO_(2) enables the oxidation of CH_(x) species to serve as carbon precursors,thus providing Ni/CeO_(2) catalysts with stronger resistance to carbon deposition compared with Ni *** Ni/CeO_(2) catalysts prepared by inverse microemulsion and impregnation methods exhibit regular semicircular spherical shape on SiC porous *** 500℃for 25 h of ESR reaction,the ethanol conversion rate over Ni/CeO_(2) catalysts(n_(CeO_(2)):n_(Ni)=7)is sustained up to 100%and H_(2) selectivity is essentially kept at 74%.The by-product selectivity declines stepwise with increasing content of CeO_(2),which is attributed to the adsorption and oxidation of CO and of CH_(x) species as CH_4 precursor from CeO_(2).The scanning electron microscopy(SEM)and transform electron microscopy(TEM)results reveal that further loading of CeO_(2) on the surface of Ni catalysts can alleviate both migration and sintering of Ni ***,carbon deposition on Ni/CeO_(2) catalysts preferentially outgrow filamentous rather than amorphous carbon,with a tendency for the latter to be more deactivated.

关键词： SiC porous Ceramic Ni/CeO_(2)catalyst Carbon deposition Ethanol steam reforming Rare earths

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