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Electric transport properties and temperature stability of magnetoresistance of composite system between La_(8/9)Sr_(1/45)Na_(4/45)MnO_3 and Sb_2O_3

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Rare Metals 2013年第4期32卷 363-368页

作者： Gui-Ying Wang yong-Gang Tang Qi-Xiang Song ming-Yu zhang Zhen-sheng Peng Anhui Key Laboratory of Spintronic and Nano-materials Research School of Mechanical and Electronic Engineering Suzhou University

The samples ofLa8/9Sr1/45Na4/45MnO3 （LSNMO）/x/2（Sb2O3） were prepared by the solid-state reaction method. The electric transport properties and the temperature stabil-ity of magnetoresistance （MR） of the samples were studied through the measurements of X-ray diffraction patterns, resistivity-temperature （ρ-T） curves, mass magnetization-temperature （σ-T） curves, and magnetoresistance-temper-ature （MR-T） curves. The results indicate that the p-Tcurves of the original material LSNMO show two peaks, and the phenomenon of two peaks of ρ-T curves disappears for the composite samples, which can be explained by a competition between surface-phase resistivity induced by boundary-dependent scattering and body-phase resistivity induced by paramagnetism-ferromagnetism transition. For all the sam-ples in the low temperature range, MR increases continu-ously with the decrease of temperature, which shows a characteristic of low-field magnetoresistance. However, MR basically keeps the same in the high temperature range. The paramagnetism-ferromagnetism transition is observed in the high temperature range due to a composite between perov-skite manganite and insulator, which can enhance the tem-perature of MR appearance in the high temperature range and make it to appear near room temperature. For the sample with x = 0.12, MR remains constant at the value of 7.5 % in the temperature range of 300-260 K, which achieves a tem-perature stability of MR near room temperature. In addition,for the sample with x = 0.16, MR is above 6.8 % in the high temperature range of 318-252 K （△T = 66 K）. MR almost remains constant in this temperature range, which favors the practical application of MR.

关键词： Electric transport property Temperaturestability of magnetoresistance Two-phase composite Perovskite manganite

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混合草坪交播黑麦草对模拟践踏的响应

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草地学报 2024年第5期32卷 1538-1547页

作者：史顺心施思杨文陆耀东宋一岚陈勇张巨明刘天增华南农业大学林学与风景园林学院广东广州510642 广东碧然美景观有限公司广东佛山528200 华南农业大学农学院广东广州510642

为研究践踏对交播多年生黑麦草(Lolium perenne)的不同品牌铺装式混合草坪的影响,本研究以2种(HERO和X-TRASS)混合草坪为试验材料,普通狗牙根(Cynodon dactylon)天然草坪为对照,通过践踏器进行8周处理。结果表明:长期践踏处理下,2种混... 详细信息

为研究践踏对交播多年生黑麦草(Lolium perenne)的不同品牌铺装式混合草坪的影响,本研究以2种(HERO和X-TRASS)混合草坪为试验材料,普通狗牙根(Cynodon dactylon)天然草坪为对照,通过践踏器进行8周处理。结果表明:长期践踏处理下,2种混合草坪的颜色、总密度、盖度等外观质量均优于天然草坪;混合草坪含有人造草纤维,具有保护作用,生物量高于天然草坪;2种混合草坪在运动质量上也具优势,第8周结果表明混合草坪在滚动距离、扭力等指标上高于天然草坪,在实际运动中,更加节省体力,利于体育赛事;其中,HERO混合草坪的外观质量和运动质量等优于X-TRASS混合草坪,其综合评价值为6.38,排名第1位。综上,混合草坪在外观质量和运动质量上均明显优于天然草坪,HERO混合草坪是建植混合草坪的最佳选择,但实际应用中需考虑如何减少表面硬度以降低场地过硬可能带来的风险。

关键词：混合草坪耐践踏性交播黑麦草

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First-Principle Studies on Adsorption of Cu^+ and Hydrated Cu^+ Cations on Clean Si(111) Surface

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Chemical Research in Chinese Universities 2010年第3期26卷 472-478页

作者： CHENG Feng-ming sheng yong-li LI Meng-hua LIU yong-jun YU zhang-yu LIU Cheng-bu School of Chemistry and Chemical Engineering School of Environmental Science and Engineering Shandong University Jinan 250100 P. R. China School of Chemistry and Chemical Engineering University of Jinan Jinan 250022 P. R. China

To study the adsorption behavior of Cu^＋ in aqueous solution on semiconductor surface, the interactions of Cu^＋ and hydrated Cu^＋ cations with the clean Si（111） surface were investigated via hybrid density functional theory（B3LYP） and Moller-Plesset second-order perturbation（MP2） method. The clean Si（111） surface was described with cluster models（Si14H17, Si16H20 and Si22H21） and a four-silicon layer slab under periodic boundary conditions. Calculation results indicate that the bonding nature of adsorption of Cu^＋ on Si surface can be viewed as partial covalent as well as ionic bonding. The binding energies between hydrated Cu^＋ cations and Si（111） surface are large, suggesting a strong interaction between them. The coordination number of Cu^＋（H2O）n on Si（111） surface was found to be 4. As the number of water molecules is larger than 5, water molecules form a hydrogen bond network. In aqueous solution, Cu^＋ cations will safely attach to the clean Si（111） surface.

关键词： Silicon surface Copper Ion-solid interaction Adsorption Density functional calculation

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Synthesis, Structure, and the Second-order Nonlinear Optical Properties of a Borate-carboxylic Acid Compound: KB[L-（-）-C4H4O5]2·H2O

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Chinese Journal of Structural Chemistry 2019年第8期38卷 1398-1403页

作者： YANG Kun YANG ming yong sheng-Li zhang Xiao-yong LUO Jun-Hua Teachers College Inner Mongolia University of Science and TechnologyBaotou 014030China State Key Laboratory of Structural Chemistry Fujian Institute of Research on the Structure of MatterChinese Academy of SciencesFuzhou 350002China

A new organic-inorganic hybrid noncentrosymmetric potassium bis(malic acid)-borates KB(L-(-)-C4H4O5)2·H2O was synthesized by solution method. It was characterized by elemental analysis, FT-IR, TGA and single-crystal X-ray crystallography. It crystallizes in the monoclinic space group P21/c with a = 5.546(6), b = 11.985(13), c = 9.952(11) ?, β = 97.522(17)°, V = 655.8(13) ?3, Z = 2, Dc = 1.682 g/cm3, μ(MoKa) = 0.46 mm–1 and F(000) = 340. 5009 reflections were measured and 2893 independent reflections(Rint = 0.051) were used for further refinement. Single-crystal X-ray diffraction reveals that the complex exhibits a threedimensional pseudo tunnel structure consisting of fundamental building block [B(L-(-)-C4H4O5)2]– anions. The small cavities are occupied by the H2O molecules, which stabilize the whole structure by O–H×××O hydrogen bonds. The complex exhibits nonlinear optical effect as high as 1.5 times that of KDP standard.

关键词： synthesis structure second-order nonlinear optical borate-carboxylic acid

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Is oxygen therapy beneficial for normoxemic patients with acute heart failure?A propensity score matched study

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Military Medical Research 2022年第3期9卷 265-276页

作者： Yue Yu Ren-Qi yao Yu-Feng zhang Su-Yu Wang Wang Xi Jun-Nan Wang Xiao-Yi Huang yong-ming yao zhi-Nong Wang Department of Cardiothoracic Surgery Changzheng HospitalNaval Medical University415 Fengyang RoadHuangpu DistrictShanghai 200003China Trauma Research Center Fourth Medical Center and Medical Innovation Research Department of the Chinese PLA General Hospital51 Fucheng RoadHaidian DistrictBeijing 100048China Department of Burn Surgery Changhai HospitalNaval Medical UniversityShanghai 200433China Medical Research Center of War Injuries and Trauma Changzheng HospitalNaval Medical UniversityShanghai 200003China Department of Pathology Changhai HospitalNaval Medical UniversityShanghai 200433China

Background:The clinical efficiency of routine oxygen therapy is uncertain in patients with acute heart failure(AHF)who do not have *** aim of this study was to investigate the association between oxygen therapy and clinical outcomes in normoxemic patients hospitalized with AHF using real-world ***:Normoxemic patients diagnosed with AHF on intensive care unit(ICU)admission from the electronic ICU(eICU)Collaborative Research Database were included in the current study,in which the study population was divided into the oxygen therapy group and the ambient air *** score matching(PSM)was applied to create a balanced covariate distribution between patients receiving supplemental oxygen and those exposed to ambient *** regression and logistic regression models were performed to assess the associations between oxygen therapy and length of stay(LOS),and all-cause in-hospital as well as ICU mortality rates,respectively.A series of sensitivity and subgroup analyses were conducted to further validate the robustness of our ***:A total of 2922 normoxemic patients with AHF were finally included in the ***,42.1%(1230/2922)patients were exposed to oxygen therapy,and 57.9%(1692/2922)patients did not receive oxygen therapy(defined as the ambient air group).After PSM analysis,1122 pairs of patients were matched:each patient receiving oxygen therapy was matched with a patient without receiving supplemental *** multivariable logistic model showed that there was no significant interaction between the ambient air and oxygen therapy for all-cause in-hospital mortality[odds ratio(OR)=1.30;95%confidence interval(CI)0.92–1.82;P=0.138]or ICU mortality(OR=1.39;95%CI 0.83–2.32;P=0.206)in the post-PSM *** addition,linear regression analysis revealed that oxygen therapy was associated with prolonged ICU LOS(OR=1.11;95%CI 1.06–1.15;P<0.001)and hospital LOS(OR=1.06;95%CI 1.01–1.10;P=0.009)after ***,the absence

关键词： Acute heart failure Death Hyperoxia Mortality Oxygen therapy

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Dynamics of soil inorganic phosphorus fractions at aggregate scales in a chronosequence of Chinese fir plantations

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Journal of Mountain Science 2022年第1期19卷 136-150页

作者： zhang Zhe HUANG yong-zhen HE Xin-xin YE Shao-ming WANG sheng-qiang Forestry college Guangxi UniversityNanning 530004China

Successive cultivation of Chinese fir(Cunninghamia lanceolata) would markedly affect the distribution and accumulation of soil inorganic phosphorus(Pi).However,how different chronosequence phases of Chinese fir plantations exerting influences on the quality and quantity of soil Pi fractions in aggregate-scale remain poorly understood. This study researched the dynamic changes of aggregate-related Pi fractions encompassing occluded-P(O-P), aluminum-bound P(Al-P), iron-bound P(Fe-P), and calcium-bound P(Ca-P) in topsoil(0-20 cm) from different stand aged(9-, 17-, and 26-yr) Chinese fir plantations and one nearby abandoned land(CK) in Rongshui County,Guangxi, China. In this study, soil aggregates were classified into micro-aggregates( 2 mm) by one wet-sieving process. As the primary aggregate fractions correlated with better soil aggregate stability, the large macro-aggregates took the highest proportion in all aggregate sizes regardless of various stand ages of Chinese fir plantations. Besides, the 17-yr plantations of Chinese fir displayed the highest stability of aggregates structure. Compared with CK, all four soil Pi fractions from three different stand ages of Chinese fir plantations generally showed increasing *** of chronosequence phases, Al-P was mainly carried by small macro-aggregates. O-P showed the opposite tendency to Al-P, which had the lowest content in small macro-aggregates. Fe-P and Ca-P showed an even distribution in all *** contribution rates and stocks of each Pi fraction exhibited close relevance to the content of soil aggregates. As revealed from the results, planting of Chinese fir before 17-yr was beneficial to prompt the formation of large macro-aggregates and the level of soil P. But after 17-yr, successive monoculture planting of Chinese fir would reduce the stability of soil aggregates and render the losses

关键词： Inorganic phosphorus fractions Soil aggregates Chinese fir plantations Cunninghamia lanceolata

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Development of Marker-Free Transgenic Cry1Ab Rice with Lepidopteran Pest Resistance by Agrobacterium Mixture-Mediated Co-transformation

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Rice science 2009年第3期16卷 181-186页

作者： QI yong-bin YE sheng-hai Lu Yan-ting JIN qing-sheng zhang Xiao-ming Institute of Crop and Nuclear Technology Utilization Zhejiang Academy of Agricultural Sciences Hangzhou 310021 China Biotechnology Institute Zhejiang University Hangzhou 310029 China

CrylAb gene was transformed into four rice varieties, Zhejing 22, Zhejing 27, Jiahua 1 and Xiushui 63 mediated by Agrobacterium-mixture co-transformation. Rice genotype had an important effect on callus induction and transformation efficiency. Different mixtures of Agrobacterium strains （EHA105 and EHA101） contained Hpt and CrylAb genes resulted in different frequencies of resistant calli. There was no correlation between the frequency of transformants with the ratio of the Agrobacterium strain mixture contained Hpt and CrylAb genes. A total of 509 transgenic plants were obtained from the four rice varieties, and 272 T2 progenies were analyzed for CrylAb and Hpt genes. PCR analysis revealed that 412 regenerated plants were Hpt positive （80.94%）, 62 plants were also CrylAb co-transformants （15.05% in total frequency）, and 42 plants among the 272 T2 progenies were CrylAb positive but Hpt negative. This suggests that marker-free transgenic plants could be produced by co-transformation mediated by mixed Agrobacterium strains with the selectable marker gene and target gene Southern blot analysis of five independent marker-free T2 transgenic lines co-transformed from Zhejing 22 showed that CrylAb gene had been inserted into rice genome with a single copy. The transgenic plants showed significantly stronger resistance to lepidopteron than the non-transgenic plants under no application of insecticides against lepidopteron.

关键词： rice (Oryza sativa) Agrobacterium mixture-mediated co-transformation CrylAb gene Hpt gene gene transfer marker-free transgenic plants pest resistance

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Optimized Electronic Modification of S-Doped CuO Induced by Oxidative Reconstruction for Coupling Glycerol Electrooxidation with Hydrogen Evolution

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Nano-Micro Letters 2023年第10期15卷 622-637页

作者： Ruo‑yao Fan Xue‑Jun Zhai Wei‑Zhen Qiao Yu‑sheng zhang Ning Yu Na Xu Qian‑Xi Lv yong‑ming Chai Bin Dong China State Key Laboratory of Heavy Oil Processing College of Chemistry and Chemical EngineeringChina University of Petroleum(East China)Qingdao 266580People’s Republic of China

Glycerol(electrochemical) oxidation reaction(GOR) producing organic small molecule acid and coupling with hydrogen evolution reaction is a critical aspect of ensuring balanced glycerol capacity and promoting hydrogen generation on a large scale. However, the development of highly efficient and selective non-noble metal-based GOR electrocatalysts is still a key problem. Here, an S-doped CuO nanorod array catalyst(S-CuO/CF) constructed by sulfur leaching and oxidative remodeling is used to drive GOR at low potentials: It requires potentials of only 1.23 and 1.33 V versus RHE to provide currents of 100 and 500 mA cm^(-2), respectively. Moreover, it shows satisfactory comprehensive performance(at 100 mA cm^(-2), V_(cell) = 1.37 V) when assembled as the anode in asymmetric coupled electrolytic cell. Furthermore, we propose a detailed cycle reaction pathway(in alkaline environment) of S-doped CuO surface promoting GOR to produce formic acid and glycolic acid. Among them, the C–C bond breaking and lattice oxygen deintercalation steps frequently involved in the reaction pathway are the key factors to determine the catalytic performance and product selectivity. This research provides valuable guidance for the development of transition metal-based electrocatalysts for GOR and valuable insights into the glycerol oxidation cycle reaction pathway.

关键词： Glycerol oxidation reaction(GOR) Hydrogen evolution reaction(HER) CuO Oxidative reconstruction Electronic modification

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The LAMOST survey of background quasars in the vicinity of M31 and M33–Ⅲ.results from the 2013 regular survey

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Research in Astronomy and Astrophysics 2015年第8期15卷 1438-1448页

作者： zhi-Ying Huo Xiao-Wei Liu Mao-sheng Xiang Jian-Rong Shi Hai-Bo Yuan Yang Huang yong zhang yong-Hui Hou Yue-Fei Wang ming Yang National Astronomical Observatories Chinese Academy of Sciences Department of Astronomy Peking University Kavli Institute for Astronomy and Astrophysics Peking University Nanjing Institute of Astronomical Optics & Technology Chinese Academy of Sciences

In this work, we report new quasars discovered in fields in the vicinity of the Andromeda（M31） and Triangulum（M33） galaxies with the Large Sky Area Multi-Object Fiber Spectroscopic Telescope（LAMOST, also called the Guo Shou Jing Telescope） during the 2013 observational season, the second year of the regular survey. In total, 1330 new quasars are discovered in an area of ～133 deg2 around M31and M33. With i magnitudes ranging from 14.79 to 20.0 and redshifts from 0.08 to4.85, the 1330 new quasars represent a significant increase in the number of identified quasars in fields in the vicinity of M31 and M33. Up to now, there have been a total of 1870 quasars discovered by LAMOST in this area. The much enlarged sample of known quasars in this area can potentially be utilized to construct a precise astrometric reference frame for the measurement of minute proper motions of M31, M33 and their associated substructures, which are vital for understanding the formation and evolution of M31, M33 and the Local Group of galaxies. Moreover, in the sample,there are a total of 45, 98 and 225 quasars with i magnitudes brighter than 17.0, 17.5and 18.0 respectively. In the aforementioned brightness bins, 15, 35 and 84 quasars are reported here for the first time, and 6, 21 and 81 are reported in our pervious work. In addition, 0, 1 and 6 are from the Sloan Digital Sky Survey and 24, 41 and 54 are from the NED database. These bright quasars provide an invaluable sample to study the kinematics and chemistry of the interstellar/intergalactic medium of the Local Group.

关键词： galaxies: individual(M31 M33)—quasars: general—quasars: emission lines

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Reactivities of Shenfu Chars Toward Gasification with Carbon Dioxide

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Journal of China University of Mining and Technology 2007年第2期17卷 197-200页

作者： zhang Jia-wei ZONG zhi-min WANG Tao-xia XIE Rui-lun DING ming-jie CAI Ke-ying HUANG yao-guo GAO Jin-sheng WU You-qing WEI Xian-yong School of Chemical Engineering China University of Mining ＆ Technology Xuzhou Jiangsu 221008 China Luohe Occupation Technical College Luohe Henan 462000 China College of Resource and Environmental Engineering East China University of Science and Technology Shanghai 200237 China

Five Shenfu char samples were prepared from Shenfu raw coal at different temperatures （950, 1100, 1200, 1300 and 1400℃） using a muffle furnace. Demineralization of the char samples was performed by treating them with 10% nitric acid for 10 min in a CEM Discover microwave reactor. The gasification of the chars, and corresponding demineralized chars, in a carbon dioxide （CO2） atmosphere was conducted in a Netzsch STA 409Cl31F tempera- ture-programmed thermogravimetry apparatus. The effects of charring temperature and demineralization on the gasification reactivity of chars were systematically investigated. The results show that a char formed at a lower temperature is more reactive except for demineralized char formed at 1100℃, which is less reactive than char formed at 1200℃. Demineralization decreases the char reactivities toward gasification with CO2 to a small extent.

关键词： demineralization temperature-programmed thermogravimetry reactivity

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