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Effects of nitrogen fertilizer and chemical regulation on spring maize lodging characteristics, grain filling and yield formation under high planting density in Heilongjiang Province, China

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Journal of Integrative Agriculture 2021年第2期20卷 511-526页

作者： liu xiao-ming GU Wan-rong LI Cong-feng LI Jing WEI Shi College of Agronomy Northeast Agricultural UniversityHarbin 150030P.R.China Institute of Crop Sciences Chinese Academy of Agricultural SciencesBeijing 100081P.R.China

Now,lodging is a major constraint factor contributing to yield loss of maize (Zea mays L.) under high planting *** regulation and nitrogen fertilizer could effectively coordinate the relationship between stem lodging and maize yield,which significantly reduce lodging and improve the grain *** purpose of this study was to explore the effects of chemical regulation and different nitrogen application rates on lodging characteristics,grain filling and yield of maize under high *** this,we established a field study during 2017 and 2018 growing seasons,with three nitrogen levels of N100 (100 kg ha^(–1)),N200 (200 kg ha^(–1)) and N300 (300 kg ha^(–1)) at high planting density (90 000 plants ha^(–1)),and applied plant growth regulator (Yuhuangjin,the mixture of 3% DTA-6 and 27% ethephon) at the 7th *** results showed that chemical control increased the activities of phenylalanine ammonia-lyase (PAL),tyrosine ammonia-lyase (TAL),4-coumarate:Co A ligase (4CL),and cinnamyl alcohol dehydrogenase (CAD),and increased the lignin,cellulose and hemicellulose contents at the bottom of the 3rd internode,which significantly reduced the lodging *** lignin-related enzyme activities,lignin,cellulose and hemicellulose contents decreased with the increase of nitrogen fertilizer,which significantly increased the lodging *** 200 kg ha^(–1) nitrogen application and chemical control increased the number,diameter,angle,volume,and dry weight of brace *** 200 kg ha^(–1) nitrogen application and chemical control significantly increased the activities of ADP-glucose pyrophosphorylase (AGPase),soluble starch synthase (SSS) and starch branching enzyme(SBE),which promoted the starch accumulation in ***,improved the maximum grain filling rate (V_(max)) and mean grain filling rate (V_(m)),which promoted the grain filling process,significantly increased grain weight and grain number per ear,thus increased the final yield.

关键词： lodging resistance grain filling starch synthesis yield maize

Improved Carrier Frequency Offset Estimation in OFDM Systems

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The Journal of China Universities of Posts and Telecommunications 2004年第Z1期11卷 33-36页

作者： liu xiao-ming liu Yuan-an Wireless Communication Center Beijing University of Posts and Telecommunications Beijing 100876 P.R.China Wireless Communication Center Beijing University of Posts and Telecommunications Beijing 100876 P.R.China

A new carrier frequency offset estimation algorithm in Orthogonal Frequency Division Multiplexing (OFDM) systems is proposed. The proposed algorithm is an improvement of the Michele Morelli (M&M) algorithm. It also uses a training symbol which is divided into L>2 identical parts to estimate the carrier frequency offset, and the estimation range is ±L/2 the subcarrier spacing, but the performance of the proposed Maximum Likelihood (ML) algorithm is more robust and complex efficient than the M&M algorithm.

关键词： frequency offset estimation multipath channel OFDM

Effects of Ligustrazine on Airway Inflammation in A Mouse Model of Neutrophilic Asthma

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Chinese Journal of Integrative Medicine 2018年第5期24卷 353-358页

作者： liu xiao-ming1 WANG Yong-bin2 WU Qian2 BIAN Zhong-rui2 CHE xiao-wen2 Department of Geriatric Medicine the Affiliated Hospital of Shandong University of Traditional Chinese Medicine Department of Respiratory Medicine the Second Hospital of Shandong University

Objective: To investigate the effects of ligustrazine(LTZ) on airway inflammation in a mouse model of neutrophilic asthma(NA). Methods: Forty healthy C57 BL/6 female mice were randomly divided into 4 groups using a random number table, including the normal control, NA, LTZ and dexamethasone(DXM) groups, with 10 rats in each group. The NA mice model was established by the method of ovalbumin combined with lipopolysaccharide sensitization. At 0.5 h before each challenge, LTZ and DXM groups were intraperitoneally injected with LTZ(80 mg/kg) or DXM(0.5 mg/kg) for 14 d, respectively, while the other two groups were given the equal volume of normal saline. After last challenge for 24 h, the aerosol inhalation of methacholine was performed and the airway reactivity was measured. The bronchoalveolar lavage fluid(BALF) was collected. The Wright-Giemsa staining was used for total white blood cells and differential counts. The levels of cytokines interleukin(IL)-17 and IL-10 were detected by enzyme-linked immunosorbent assay. The pathological change of lung tissue was observed by hematoxylin eosin staining. Results: The airway responsiveness of the NA group was significantly higher than the normal control group(P<0.05), while those in the LTZ and DXM groups were significantly lower than the NA group(P<0.05). The neutrophil and eosinophil counts in the LTZ and DXM groups were significantly lower than the NA group(P<0.05), and those in the LTZ group were significantly lower than the DXM group(P<0.05). There were a large number of peribronchiolar and perivascular inflammatory cells in filtration in the NA group. The airway inflammation in the LTZ and DXM groups were significantly alleviated than the NA group. The infiltration in the LTZ group was significantly reduced than the DXM group. Compared with the normal control group, the IL-17 level in BALF was significantly increased and the IL-10 level in BALF was significantly decreased in the NA group(P<0.05). LTZ and DXM treatment

关键词： ligustrazine neutrophilic asthma airway inflammation cytokine

Syntheses, Structures, and Blue Luminescent Properties of 2,6-Bis-(benzimidazolyl) Pyridine and Its Mercury Complex

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Chemical Research in Chinese Universities 2007年第2期23卷 159-162页

作者： liu xiao-ming MU xiao-yue XIA Hong SU Qing YE Ling CHEN Chao GAO Wei MU Ying Key Laboratory for Supramolecular Structure and Materials of Ministry of Education College of Chemistry Jilin University Changchun 130012 P. R. China State Key Laboratory of Inorganic Synthesis and Preparative Chemistry College of Chemistry Jilin University Changchun 130012 P. R. China

A novel blue luminescent mercury （ Ⅱ ） complex of 2,6-bis （benzimidazolyl） pyridine （L） was synthesized. In solid state, this complex has the formula [Hg（L）Cl2] · 2DMF（1）. The molecular structures of both the ligand and the complex were determined by using tingle-crystal X-ray diffraction. Crystallographic studies of the mercury （ Ⅱ） complex reveal that the complex possesses a five-coordinated geometry that can be best described as a distorted trigonal-bipyramidal. The luminescent properties of ligand L and complex 1 both in solution and in solid state were also studied.

关键词： 2,6-Bis (benzimidazolyl) pyridine Mercury Crystal structure Blue luminescence

Effect of shade stress on lignin biosynthesis in soybean stems

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Journal of Integrative Agriculture 2018年第7期17卷 1594-1604页

作者： liu Wei-guo REN Meng-lu liu Ting DU Yong-li ZHOU Tao liu xiao-ming liu Jiang Sajad Hussain YANG Wen-yu Institute of Ecological Agriculture Sichuan Agricultural University/Sichuan Engineering Research Center for Crop Strip Intercropping System

To clarify how shade stress affects lignin biosynthesis in soybean stem, two varieties, Nandou 12（shade tolerant） and Nan 032-4（shade susceptible） grew under normal light and shade conditions（the photosynthetically active radiation and the ratio of red：far-red were lower than normal light condition）. Lignin accumulation, transcripts of genes involved in lignin biosynthesis, and intermediates content of lignin biosynthesis were analyzed. Both soybean varieties suffered shade stress had increased plant heights and internode lengths, and reduced stem diameters and lignin accumulation in stems. The expression levels of lignin-related genes were significantly influenced by shade stress, with interactions between the light environment and variety. The gene of 3-hydroxylase（C3H）, cinnamoyl-Co A reductase（CCR）, caffeoylCoAO-methyltransferase（CCoAOMT）, and peroxidase（POD） attributed to lignin biosynthesis under shade stress, and the down-regulation of these genes resulted in lower caffeic, sinapic, and ferulic acid levels, which caused a further decrease in lignin biosynthesis. Under shade stress, the shade tolerant soybean variety（Nandou 12） showed stiffer stems, higher lignin content, and greater gene expression level and higher metabolite contents than shade susceptible one. So these characteristics could be used for screening the shade-tolerant soybean for intercropping.

关键词： Glycine max stem shade stress lignin biosynthesis gene expression phenolic acids

Screening and Characterization of a Bioflocculant Produced by Aeromonas sp

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Biomedical and Environmental Sciences 2007年第4期20卷 274-278页

作者： JIN-JING liu xiao-ming LI QI YANG KAI HUANG GUANG-ming ZENG DE-XIANG LIAO WEN-FANG LONG College of Environmental Science and Engineering Hunan University Changsha 410082 Hunan China

To isolate the bioflocculant-producing bacteria from activated sludge and investigate the flocculating characteristics of the newly isolated bioflocculant. Methods Bacteria were screened from activated sludge samples to isolate bioflocculant-producing bacteria. Flocculating activity was used as a measure of the flocculating capability of the bioflocculant. Results A novel bioflocculant-producing bacterium was isolated, which was identified to belong to genus Aeromonas and named as Aeromonas sp. Nil. Flocculating activity increased in the presence of K, Na^＋, or Ca^2＋. The highest flocculating activities for kaolin suspension were obtained in acidic pH ranges, and optimum pHs for it were 3.0, 4.0, and 5.0 with 1 mmol/L K^＋, Ca^＋, and Na^＋ present, respectively. The highest flocculating activities for soil suspension were observed at pH 8.0. The bioflocculant had a good flocculating activity and could achieve a flocculating activity of 92.4% for kaolin suspension at a dosage of only 1 mg.L-1, and its activity in kaolin suspension was decreased by only 9.2% after heating at 100℃ for 60 min. Conclusion The bioflocculant produced by Aeromonas sp. Nil has strong flocculating activity and high stability, which affords high possibility of its practical use.

关键词： Aeromonas sp. Bioflocculant Biopolymer Flocculation

Double negative optical metamaterial with all-dielectric fishnet structure

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Double negative optical metamaterial with all-dielectric fis...

Cementing Properties of Oil Shale Ash

第八届中国功能材料及其应用学术会议

作者： LAN Chu-wen FU xiao-jian liu xiao-ming LI Bo ZHOU Ji State Key Lab of New Ceramics and Fine Processing School of Materials Scienceand EngineeringTsinghua University Advanced Materials Institute Shenzhen Graduate SchoolTsinghua University

ISBN: (纸本)9783037859698

An all-dielectric fishnet metamaterial(DFM) composed ofmultilayer dielectric structure with periodically patterned holes is proposed to generate left-handed behavior in optical frequency *** from the metallic fishnet negative index metamaterial realized by coupling the neighbouring functional layersalong the propagation direction,this DFM owes its simultaneous negative permeability and permittivity to the hybrid coupled resonances in the same *** on this configration,a wide-band and polarization-independent negative refraction with maximumfigure of merit as large as 13.85 is obtained by a silicon-based DFM at 450 nm *** and easy to fabricate,this concept is believed to provide an alternative route to realize high-performance negative index metamateirals at optical frequencies.

关键词： left-handed metamaterial all-dielectric fishnet coupling effect negative refraction backward wave propagation

来源： cnki会议评论

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Journal of China University of Mining and Technology 2007年第4期17卷 498-502页

作者： FENG Xiang-peng NIU Xue-lian BAI Xue liu xiao-ming SUN Heng-hu Department of Materials Science and Engineering Tsinghua University Beijing 100084 China School of Resource and Safety Engineering China University of Mining ＆ Technology Beijing 100083 China

The oil crisis has prompted renewed interest in direct burning of oil shale as an alternative energy source. A major problem in this process is the large portion of ash produced. The cementing properties of this ash were investi-gated to determine its applicability as a building material. By means of XRD,IR,NMR and ICP,we have studied the effects of burning temperature on the reactivity of ash. Maximum reactivity was obtained with ash samples produced at 700℃ to 900℃. In this range,the strength of oil-shale-based material,with properties similar to cement,which is composed of oil shale and several other kinds of solid wastes,can achieve the standard of 42.5^# cement. Our study has provided an experimental foundation and theoretical base for a massive utilization of oil shale.

关键词： oil shale thermal activation cementitious activity

Bauschinger and size effects in thin-film plasticity due to defect-energy of geometrical necessary dislocations

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Acta Mechanica Sinica 2011年第2期27卷 266-276页

作者： Zhan-Li liu · Zhuo Zhuang · xiao-ming liu · Xue-Chuan Zhao · Yuan Gao Department of Engineering Mechanics, School of Aerospace, Tsinghua University, 100084 Beijing, China Department of Engineering Mechanics School of Aerospace Tsinghua University Beijing China

The Bauschinger and size effects in the thinfilm plasticity theory arising from the defect-energy of geometrically necessary dislocations （GNDs） are analytically investigated in this paper. Firstly, this defect-energy is deduced based on the elastic interactions of coupling dislocations （or pile-ups） moving on the closed neighboring slip plane. This energy is a quadratic function of the GNDs density, and includes an elastic interaction coefficient and an energetic length scale L. By incorporating it into the work- conjugate strain gradient plasticity theory of Gurtin, an energetic stress associated with this defect energy is obtained, which just plays the role of back stress in the kinematic hardening model. Then this back-stress hardening model is used to investigate the Bauschinger and size effects in the tension problem of single crystal Al films with passivation layers. The tension stress in the film shows a reverse dependence on the film thickness h. By comparing it with discrete-dislocation simulation results, the length scale L is determined, which is just several slip plane spacing, and accords well with our physical interpretation for the defect- energy. The Bauschinger effect after unloading is analyzed by combining this back-stress hardening model with a friction model. The effects of film thickness and pre-strain on the reversed plastic strain after unloading are quantified and qualitatively compared with experiment results.

关键词： Thin film · Crystal plasticity · Defect energy · Back stress · Size effect